FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Habelitz, S Marshall, SJ Marshall, GW Balooch, M AF Habelitz, S Marshall, SJ Marshall, GW Balooch, M TI Mechanical properties of human dental enamel on the nanometre scale SO ARCHIVES OF ORAL BIOLOGY LA English DT Article DE enamel rod; nanohardness; modulus; tooth orientation; anisotropy; etching ID FRACTURE PROPERTIES; ELASTIC-MODULUS; YOUNG MODULUS; HARDNESS; NANOINDENTATION; INDENTATION; JUNCTION; CRYSTALS; TEETH AB Atomic force microscopy (AFM) combined with a nano-indentation technique was used to reveal the structure and to perform site-specific mechanical testing of the enamel of third molars. Nano-indentations (size < 500 nan) were made in the cusp area to measure the mechanical properties of single enamel rods at different orientations. The influence of etching on the physical properties was studied and etching conditions that did not significantly alter the plastic-elastic response of enamel were defined. Elasticity and hardness were found to be a function of the microstructural texture. Mean Young's moduli of 87.5 (2.2) and 72.7(+/-4.5) GPa and mean hardness of 3.9 +/- 0.3 and 3.3 +/- 0.3 GPa were measured in directions parallel and perpendicular to the enamel rods, respectively. Analysis of variance showed that the differences were significant. The observed anisotropy of enamel is related to the alignment of fibre-like apatite crystals and the composite nature of enamel rods. Mechanical properties were also studied at different locations on single enamel rods. Compared to those in the head area of the rods, Young's moduli and hardness were lower in the tail area and in the inter-rod enamel, which can be attributed to changes in crystal orientation and the higher content of soft organic tissue in these areas. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif San Francisco, Dept Prevent & Restorat Dent Sci, San Francisco, CA 94143 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. RP Marshall, SJ (reprint author), Univ Calif San Francisco, Dept Prevent & Restorat Dent Sci, 707 Parnassus Ave, San Francisco, CA 94143 USA. FU NIDCR NIH HHS [R01-DE 13029] NR 34 TC 257 Z9 279 U1 8 U2 67 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0003-9969 J9 ARCH ORAL BIOL JI Arch. Oral Biol. PD FEB PY 2001 VL 46 IS 2 BP 173 EP 183 DI 10.1016/S0003-9969(00)00089-3 PG 11 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 398WZ UT WOS:000166780600009 PM 11163325 ER PT J AU Brodrick, JR Westphalen, D AF Brodrick, JR Westphalen, D TI Uncovering auxiliary energy use SO ASHRAE JOURNAL LA English DT Article AB A new government study has found that auxiliary equipment in commercial-building HVAC systems uses much more energy than previously thought. The Department of Energy (DOE) report conservatively estimates that auxiliary fans and pumps use 1.5 quadrillion Btu (quads) nationwide-about 10% of all energy used in the commercial sector. This equipment has been largely overlooked in energy-efficiency research, development & deployment (RD&D) programs, which have mainly focused on improving the efficiency of primary heating and cooling equipment such as chillers, refrigerant compressors, boilers and furnaces.(1) Furthermore, auxiliary energy consumption most likely is increasing, even as primary equipment is showing vast improvements in efficiency. C1 US DOE, Off Bldg Technol, Washington, DC 20585 USA. Arthur D Little Inc, Technol & Innovat Business, HVAC & Refrigerat Unit, Cambridge, MA 02140 USA. RP Brodrick, JR (reprint author), US DOE, Off Bldg Technol, Washington, DC 20585 USA. NR 11 TC 11 Z9 11 U1 0 U2 2 PU AMER SOC HEATING REFRIGERATING AIR-CONDITIONING ENG, INC, PI ATLANTA PA 1791 TULLIE CIRCLE NE, ATLANTA, GA 30329 USA SN 0001-2491 J9 ASHRAE J JI ASHRAE J. PD FEB PY 2001 VL 43 IS 2 BP 58 EP 61 PG 4 WC Thermodynamics; Construction & Building Technology; Engineering, Mechanical SC Thermodynamics; Construction & Building Technology; Engineering GA 403NB UT WOS:000167048400010 ER PT J AU Morgan, ND Becker, RH Gregg, MD Schechter, PL White, RL AF Morgan, ND Becker, RH Gregg, MD Schechter, PL White, RL TI The gravitational lens candidate FBQ 1633+3134 SO ASTRONOMICAL JOURNAL LA English DT Article DE gravitational lensing; quasars : individual (FBQ 1633+3134) ID BINARY QUASAR; COSMOLOGICAL CONSTANT; MG 0414+0534; GALAXIES; REDSHIFTS; SPECTRA; SYSTEMS; COLORS; PAIRS AB We present our ground-based optical imaging, spectral analysis, and high-resolution radio mapping of the gravitational lens candidate FBQ 1633 + 3134. This z = 1.52, B = 17.7 quasar appears double on CCD images with an image separation of 0".66 and a relatively constant flux ratio of similar to3:1 across B, V, R, and I filters. A single 0.27 mJy radio source is detected at 8.46 GHz, coincident within an arc-second of both optical components, but no companion at radio wavelengths is detected for the system down to a flux level of 0.1 mJy (3 sigma). Spectral observations reveal a rich metal-line absorption system consisting of a strong Mg II doublet and associated Fe I and Fe II absorption features, all at an intervening redshift of z = 0.684, suggestive of a lensing galaxy. Point-spread function subtraction of groundbased images however shows no obvious signs of a third object between the two quasar images and places a detection limit of if such an object exists. Although the possibility that FBQ I greater than or similar to 23.0 1633 + 3134 is a binary quasar cannot be ruled out, the evidence presented here is consistent with FBQ 1633 + 3134 being a single quasar lensed by a faint, metal-rich galaxy. C1 MIT, Dept Phys, Cambridge, MA 02139 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Morgan, ND (reprint author), MIT, Dept Phys, Room 6-113,77 Massachusetts Ave, Cambridge, MA 02139 USA. EM ndmorgan@mit.edu; bob@igpp.ucllnl.org; gregg@igpp.ucllnl.org; schech@achernar.mit.edu; rlw@stsci.edu NR 33 TC 13 Z9 13 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD FEB PY 2001 VL 121 IS 2 BP 611 EP 618 DI 10.1086/318744 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 401QL UT WOS:000166939700003 ER PT J AU Keller, SC Da Costa, GS Bessell, MS AF Keller, SC Da Costa, GS Bessell, MS TI Young clusters in the Magellanic Clouds. II SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : star clusters; Magellanic Clouds; stars : evolution ID EVOLUTIONARY MODELS; MASSIVE STARS; RADIATIVE OPACITIES; NGC-1866; NGC-330; SUPERGIANTS; SEQUENCES; DIAGRAMS AB We present the results of a quantitative study of the degree of extension to the boundary of the classical convective core within intermediate-mass stars. The basis of our empirical study is the stellar population of four young populous clusters in the Magellanic Clouds that has recently been detailed by Keller, Bessell, & Da Costa. The sample affords a meaningful comparison with theoretical scenarios with varying degrees of convective core overshoot and binary star fraction. Two critical properties of the population, the main-sequence luminosity function and the number of evolved stars, form the basis of our comparison between the observed data set and that simulated from the stellar evolutionary models. On the basis of this comparison we conclude that the case of no convective core overshoot is excluded at a 2 sigma level. C1 Australian Natl Univ, Inst Adv Studies, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. RP Keller, SC (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-413,7000 East Ave, Livermore, CA 94551 USA. NR 33 TC 15 Z9 15 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD FEB PY 2001 VL 121 IS 2 BP 905 EP 915 DI 10.1086/318741 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 401QL UT WOS:000166939700023 ER PT J AU Richards, GT Laurent-Muehleisen, SA Becker, RH York, DG AF Richards, GT Laurent-Muehleisen, SA Becker, RH York, DG TI Quasar absorption lines as a function of quasar orientation measures SO ASTROPHYSICAL JOURNAL LA English DT Article DE intergalactic medium; quasars : absorption lines; radio continuum : galaxies ID C-IV ABSORPTION; RADIO-SOURCES; SYSTEMS; SPECTRA; QSOS AB We present high-resolution radio data at 3.5 and 20 cm from the VLA in the A configuration for 144 quasars with known C IV absorption-line properties. Using these measurements, we compare and contrast a number of quasar orientation indicators. These quantities are used to study the velocity distribution of C IV absorption lines as a function of quasar orientation measures. That there is an excess of narrow, high-velocity C IV absorbers in flat spectrum quasars as compared to steep spectrum quasars is confirmed. Orientation indicators that are not based upon spectral indices (e.g., R-V and the core-to-lobe ratio) do not show the same effect. These seemingly contradictory results may be reconciled if the absorber distribution is not strictly a function of orientation, but rather a function of intrinsic radio properties that may or may not be good orientation indicators. C1 Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Univ Calif Davis, Livermore, CA 94550 USA. LLNL, IGPP, Livermore, CA 94550 USA. RP Richards, GT (reprint author), Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. NR 14 TC 19 Z9 19 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 1 PY 2001 VL 547 IS 2 BP 635 EP 648 DI 10.1086/318414 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 397ZF UT WOS:000166728300011 ER PT J AU Pariev, VI Bromley, BC Miller, WA AF Pariev, VI Bromley, BC Miller, WA TI Estimation of relativistic accretion disk parameters from iron line emission SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; galaxies : active; line : profiles; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; SEYFERT-1 GALAXY NGC-3516; INNERMOST STABLE ORBIT; ROTATING BLACK-HOLE; ASCA OBSERVATIONS; COLD MATTER; NGC 4151; MCG-6-30-15; PROFILES; REVERBERATION AB The observed iron K alpha fluorescence lines in Seyfert 1 galaxies provide strong evidence for an accretion disk near a supermassive black hole as a source of the emission. Here we present an analysis of the geometrical and kinematic properties of the disk based on the extreme frequency shifts of a line profile as determined by measurable flux in both the red and blue wings. The edges of the line are insensitive to the distribution of the X-ray flux over the disk and hence provide a robust alternative to profile fitting of disk parameters. Our approach yields new, strong bounds on the inclination angle of the disk and the location of the emitting region. We apply our method to interpret observational data from MCG -6-30-15 and find that the commonly assumed inclination 30 degrees for the accretion disk in MCG -6-30-15 is inconsistent with the position of the blue edge of the line at a 3 sigma level. A thick turbulent disk model or the presence of highly ionized iron may reconcile the bounds on inclination from the line edges with the full line profile fits based on simple, geometrically thin disk models. The bounds on the innermost radius of disk emission indicate that the black hole in MCG -6-30-15 is rotating faster than 30% of theoretical maximum. When applied to data from NGC 4151, our method gives bounds on the inclination angle of the X-ray-emitting inner disk of 50 degrees +/- 10 degrees, consistent with the presence of an ionization cone grazing the disk as proposed by Pedlar. The frequency extrema analysis also provides limits to the innermost disk radius in another Seyfert 1 galaxy, NGC 3516, and is suggestive of a thick-disk model. C1 Univ Calif Los Alamos Natl Lab, Theoret Astrophys Grp, Los Alamos, NM 87545 USA. Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. RP Pariev, VI (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. NR 55 TC 21 Z9 21 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 FEB 1 PY 2001 VL 547 IS 2 BP 649 EP 666 DI 10.1086/318407 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 397ZF UT WOS:000166728300012 ER PT J AU Kishimoto, M Antonucci, R Cimatti, A Hurt, T Dey, A van Breugel, W Spinrad, H AF Kishimoto, M Antonucci, R Cimatti, A Hurt, T Dey, A van Breugel, W Spinrad, H TI Ultraviolet spectropolarimetry of narrow-line radio galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; polarization; quasars : general; scattering; ultraviolet : galaxies ID SEYFERT 2 GALAXIES; IMAGING POLARIMETRY; INFRARED OBSERVATIONS; OPTICAL POLARIZATION; STARBURST GALAXIES; MAGELLANIC-CLOUD; DUST EXTINCTION; ACTIVE GALAXIES; QUASARS; CONTINUUM AB We present the results of UV spectropolarimetry (lambda (rest) similar or equal to 2000-3000 Angstrom) and far-UV spectroscopy (lambda (rest) similar or equal to 1500-2000 Angstrom) of two low-redshift narrow-line radio galaxies (NLRGs) taken with the Faint Object Spectrograph on board the Hubble Space Telescope (HST). Spectropolarimetry of several NLRGs has shown that, by the presence of broad permitted lines in polarized flux spectrum, they have hidden quasars seen through scattered light. Imaging polarimetry has shown that NLRGs including our targets often have large scattering regions of a few to greater than or similar to 10 kpc scale. This has posed a problem concerning the nature of the scatterers in these radio galaxies. Their polarized continuum has the spectral index similar to or no bluer than that of quasars, which favors electrons as the dominant scattering particles. The large scattering region size, however, favors dust scattering because of its higher scattering efficiency compared to electrons. In this paper we investigate the polarized flux spectrum over a wide wavelength range, combining our UV data with previous optical/infrared polarimetry data. We infer that the scattering would be often caused by opaque dust clouds in the NLRGs and this would be part of the reason for the apparently gray scattering. In the high-redshift radio galaxies, these opaque clouds could be the protogalactic subunits inferred to be seen in the HST images. However, we still cannot rule out the possibility of electron scattering, which could imply the existence of a large gas mass surrounding these radio galaxies. C1 Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. Natl Opt Astron Observ, Tucson, AZ 85719 USA. Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Kishimoto, M (reprint author), Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. NR 82 TC 20 Z9 20 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 FEB 1 PY 2001 VL 547 IS 2 BP 667 EP 683 DI 10.1086/318403 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 397ZF UT WOS:000166728300013 ER PT J AU Wojdowski, PS Liedahl, DA Sako, M AF Wojdowski, PS Liedahl, DA Sako, M TI The X-ray photoionized wind in Cen X-3/V779 Cen SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; binaries : eclipsing; stars : neutron; stars : winds, outflows; X-rays : stars ID RADIATION-DRIVEN WINDS; VELA X-1; CENTAURUS X-3; STELLAR WINDS; CIRCUMSTELLAR MATTER; ACCRETION DISKS; LINE EMISSION; MASS-TRANSFER; HOT STARS; SMC X-1 AB We analyze the ASCA spectrum of the Cen X-3 X-ray binary system in eclipse using atomic models appropriate to recombination-dominated level population kinetics in an overionized plasma. In order to estimate the wind characteristics, we first fit the eclipse spectrum to a single-zone photoionized plasma model. We then fit spectra from a range of orbital phases using global models of photoionized winds from the companion star and the accretion disk that account for the continuous distribution of density and ionization state. We find that the spectrum can be reproduced by a density distribution of the form derived by Castor et al. (1975) for radiation-driven winds with (M) over dot/v(infinity) consistent with values for isolated stars of the same stellar type. This is surprising because the neutron star is very luminous (similar to 10(38) ergs s(-1)) and the X-rays from the neutron star should ionize the wind and destroy the ions that provide the opacity for the radiation-driven wind. Using the same functional form for the density profile, we also fit the spectrum to a spherically symmetric wind centered on the neutron star, a configuration chosen to represent a disk wind. We argue that the relatively modest orbital variation of the discrete spectrum rules out a disk wind hypothesis. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94551 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. RP Wojdowski, PS (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys, POB 808, Livermore, CA 94551 USA. NR 68 TC 11 Z9 11 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 FEB 1 PY 2001 VL 547 IS 2 BP 973 EP 987 DI 10.1086/318425 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 397ZF UT WOS:000166728300039 ER PT J AU Ofman, L Vinas, A Gary, SP AF Ofman, L Vinas, A Gary, SP TI Constraints on the O+5 anisotropy in the solar corona SO ASTROPHYSICAL JOURNAL LA English DT Article DE solar wind; Sun : corona; Sun : magnetic fields; waves ID WIND; TEMPERATURE; INSTABILITY; SIMULATION; VELOCITY; MODELS; WAVES AB Velocity distributions of O+5 ions derived from Ultraviolet Coronagraph Spectrometer (UVCS) observations in coronal holes indicate that the O+5 ions are highly anisotropic (T-perpendicular toi/T-parallel toi approximate to 30-300 at 3.5 R-.). The observations provide empirical values for the electron density and the ion temperatures. It is well known that the electromagnetic ion cyclotron instability is driven by temperature anisotropy. The instability leads to the rapid decrease of anisotropy and transfer of part of the kinetic energy of the particles into the magnetic field fluctuations. Here we use linear theory and hybrid simulations combined with the empirical values of the densities and the temperatures to investigate the ion cyclotron instability of the anisotropic minor ions in the coronal hole plasma. We find that an initial O+5 anisotropy of 50 decreases by an order of magnitude within similar to 300-900 proton cyclotron periods. Thus, the ion cyclotron instability constrains the anisotropy of O+5 ions that can be sustained in the solar corona without continuous perpendicular heating. C1 NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Raytheon ITSS, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ofman, L (reprint author), NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Raytheon ITSS, Mail Code 682, Greenbelt, MD 20771 USA. NR 21 TC 38 Z9 38 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 FEB 1 PY 2001 VL 547 IS 2 BP L175 EP L178 DI 10.1086/318900 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 398BA UT WOS:000166732800020 ER PT J AU Volkow, ND Ding, YS Fowler, JS Gatley, SJ AF Volkow, ND Ding, YS Fowler, JS Gatley, SJ TI Imaging brain cholinergic activity with positron emission tomography: Its role in the evaluation of cholinergic treatments in Alzheimer's dementia SO BIOLOGICAL PSYCHIATRY LA English DT Article; Proceedings Paper CT Symposium on Nicotine Mechanisms in Alzheimers Disease CY MAR 16-18, 2000 CL FAJARKO, PR SP Soc Biol Psychiat DE nicotinic receptors; muscarinic receptors; cholinesterase; amyloid; FDG ID NICOTINIC ACETYLCHOLINE-RECEPTORS; CEREBRAL-BLOOD-FLOW; IN-VIVO; GLUCOSE-METABOLISM; RHESUS-MONKEY; NONHUMAN-PRIMATES; TACRINE TREATMENT; C-11 RACLOPRIDE; BINDING-SITES; DISEASE AB One of the strategies in the treatment of Alzheimer's disease is the use of drugs that enhance cholinergic br ain function, since it is believed that cholinergic dysfunction is one of the factors that contributes to cognitive deterioration.. Positron emission tomography is a medical imaging method that can be used to measure the concentration, kinetics, and distribution of cholinergic-enhancing drugs directly in the human brain and assess the effects of the drugs at markers of cholinergic cell viability (vesicular transporters, acetylcholinesterase), at muscarininc and nicotinic receptors, at extracellular acetylcholine, at markers of brain function (glucose metabolism and blood flow), and on amyloid plaque burden in vivo in the brains of patients with Alzheimer's disease. In addition, these measures call be applied to assess the drugs' pharmacokinetic and pharmacodynamic properties in the human brain. Since the studies ale done in living human subjects, positron emission tomography can evaluate the relationship between the drugs' biological, behavioral, and cognitive effects; monitor changes in brain function in response to chronic treatment; and determine if phamacologic interventions are neuroprotective. Moreover, because positron emission tomography has the potential to identify Alzheimer's disease during early disease, if can be used to establish whether early interventions cai? prevent or delay futher development. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Dept Med, Bldg 490, Upton, NY 11973 USA. FU NIDA NIH HHS [DA06278, DA09490] NR 70 TC 44 Z9 47 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0006-3223 J9 BIOL PSYCHIAT JI Biol. Psychiatry PD FEB 1 PY 2001 VL 49 IS 3 BP 211 EP 220 DI 10.1016/S0006-3223(00)01112-4 PG 10 WC Neurosciences; Psychiatry SC Neurosciences & Neurology; Psychiatry GA 404DM UT WOS:000167082200007 PM 11230872 ER PT J AU Wofsy, C Coombs, D Goldstein, B AF Wofsy, C Coombs, D Goldstein, B TI Calculations show substantial serial engagement of T cell receptors SO BIOPHYSICAL JOURNAL LA English DT Article ID SIGNAL-TRANSDUCTION; TCR ENGAGEMENT; PEPTIDE; ACTIVATION; LIGANDS; DYNAMICS; COMPLEXES; KINETICS; AFFINITIES; DIFFUSION AB The serial engagement model provides an attractive and plausible explanation for how a typical antigen presenting cell, exhibiting a low density of peptides recognized by a T cell, can initiate T cell responses. If a single peptide displayed by a major histocompatibility complex (MHC) can bind, sequentially, to different T cell receptors (TCR), then a few peptides can activate many receptors. To date, arguments supporting and questioning the prevalence of serial engagement have centered on the down-regulation of TCR after contact of T cells with antigen presenting cells. Recently, the existence of serial engagement has been challenged by the demonstration that engagement of TCR can down-regulate nonengaged bystander TCR, Here we show that for binding and dissociation rates that characterize interactions between T cell receptors and peptide-MHC, substantial serial engagement occurs. The result is independent of mechanisms and measurements of receptor down-regulation. The conclusion that single peptide-MHC engage many TCR, before diffusing out of the contact region between the antigen-presenting cell and the T cell, is based on a general first passage time calculation for a particle alternating between states in which different diffusion coefficients govern its transport. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Theoret Biol & Biophys Grp, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. Univ Arizona, Program Appl Math, Tucson, AZ 85721 USA. RP Goldstein, B (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Theoret Biol & Biophys Grp, T-10,MS K710, Los Alamos, NM 87545 USA. OI Coombs, Daniel/0000-0002-8038-6278 FU NIGMS NIH HHS [GM35556] NR 33 TC 46 Z9 46 U1 0 U2 0 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD FEB PY 2001 VL 80 IS 2 BP 606 EP 612 PG 7 WC Biophysics SC Biophysics GA 398PP UT WOS:000166765100004 PM 11159429 ER PT J AU Call, DR Chandler, DP Brockman, F AF Call, DR Chandler, DP Brockman, F TI Fabrication of DNA microarrays using unmodified oligonucleotide probes SO BIOTECHNIQUES LA English DT Article ID HYBRIDIZATION; MICROCHIPS; ARRAYS; DIAGNOSTICS; DISCOVERY; SURFACE; GENES AB Microarrays printed on glass slides are often constructed by covalently linking oligonucleotide probes to a derivatized surface. These procedures typically require relatively expensive amine- or thiol-modified oligonucleotide probes that add considerable expense to larger arrays. We describe a system by which unmodified oligonucleotide probes are bound to either non-derivatized or epoxy-silane-derivatized glass slides. Biotinylated PCR products are heat denatured, hybridized to the arrays, and detected using an enzymatic amplification system. Unmodified probes appear to detach from the slide surface at high pH (>10.0), suggesting that hydrogen bonding plays a significant role in probe attachment. Regardless of surface preparation, high temperature (up to 65 degreesC) and low ionic strength (deionized water) do not disturb probe attachment; hence, the fabrication method described here is suitable for a wide range of hybridization stringencies and conditions. We illustrate kinetics of room temperature hybridizations for probes attached to nonderivatized slides, and we demonstrate that unmodified probes produce hybridization signals equal to amine-modified, covalently bound probes. Our method provides a cost-effective alternative to conventional attachment strategies that is particularly suitable for genotyping PCR products with nucleic acid microarrays. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Call, DR (reprint author), Washington State Univ, Dept Vet Microbiol & Pathol, POB 647040, Pullman, WA 99164 USA. NR 20 TC 69 Z9 76 U1 0 U2 6 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD FEB PY 2001 VL 30 IS 2 BP 368 EP + PG 8 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 400ZL UT WOS:000166902500025 PM 11233606 ER PT J AU Thulasiraman, V McCutchen-Maloney, SL Motin, VL Garcia, E AF Thulasiraman, V McCutchen-Maloney, SL Motin, VL Garcia, E TI Detection and identification of virulence factors in Yersinia pestis using SELDI ProteinChip (R) system SO BIOTECHNIQUES LA English DT Article ID LOW-CALCIUM RESPONSE; PLAGUE AB A rapid method for the detection, purification, and identification of proteins in bacterial extracts was developed using surface enhanced laser desorption/ionization (SELDI) ProteinChip(R) technology. The effectiveness of this technique for monitoring the expression and identification of temperature- and calcium-regulated virulence factors of Yersinia pestis, the bacterium that causes human plague, is demonstrated. Y. pestis infection of its mammalian host is thought to be accompanied by rapid up-regulation of a number of genes following a shift from 26 degreesC (the temperature of the flea vector) to 37 degreesC (the temperature of the mammalian host). To model this process, Y. pestis cells were grown at 26 degreesC and 37 degreesC in a Ca2+-deficient medium. through an initial protein profiling of the crude bacterial extract on strong anion exchange and copper affinity, ProteinChip arrays detected five proteins that were up-regulated and three proteins that were down-regulated at 37 degreesC. Two of the proteins predominately expressed at 37 degreesC were semi-purified in less than two days. The two proteins were identified as catalase-peroxidase and Antigen 4. Aside from its speed, a salient feature of the SELDI technique is the microgram amounts of crude sample required for analysis. C1 Ciphergen Biosyst Inc, Fremont, CA USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Thulasiraman, V (reprint author), Ciphergen Biosyst Inc, 6611 Dumbarton Circle, Fremont, CA USA. RI Motin, Vladimir/O-1535-2013 NR 11 TC 37 Z9 48 U1 0 U2 0 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD FEB PY 2001 VL 30 IS 2 BP 428 EP 432 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 400ZL UT WOS:000166902500032 PM 11233613 ER PT J AU Sadana, A Vo-Dinh, T AF Sadana, A Vo-Dinh, T TI Biomedical implications of protein folding and misfolding SO BIOTECHNOLOGY AND APPLIED BIOCHEMISTRY LA English DT Review DE aggregate; fractal; mechanism; parallel; series ID CHAIN BINDING-PROTEIN; ENDOPLASMIC-RETICULUM; PRO-REGION; MOLECULAR CHAPERONES; ESCHERICHIA-COLI; FRACTAL ANALYSIS; MATCHING SPEED; 1/F NOISE; RNA; CATALYSTS AB A review of protein-folding mechanisms is presented to indicate (i) the formation of correctly folded and misfolded forms, and (ii) the biomedical implications involved. Protein mechanisms may be classified into series and series-parallel mechanisms. The mechanism may involve one or more stable intermediate (partially folded, misfolded, with some structure) states. It is the parallel or the 'off-pathway' step(s) that lead to the aggregate (misfolded state). This aggregate state yields the amyloid deposits in human tissue that lead to diseases in humans that are resistant to treatment. Means by which the off-pathway step may be minimized and the correct folding pathway enhanced are presented. Particular emphasis is placed on the in vivo machinery (chaperones) that is in place in the cells, and how it functions to allow the proteins to fold in the correct and active form, thus minimizing the amyloid deposits in tissues. More effort needs to be placed to understand the function of these chaperones, and thus help facilitate the formation of active and stable proteins in the cells. Though more effort needs to be placed in the present treatment strategies, novel treatment procedures also need to be explored in order to develop effective strategies to treat these seemingly intractable diseases. C1 Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. Univ Mississippi, Dept Chem Engn, University, MS 38677 USA. RP Vo-Dinh, T (reprint author), Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. NR 89 TC 13 Z9 13 U1 0 U2 0 PU PORTLAND PRESS PI LONDON PA 59 PORTLAND PLACE, LONDON W1N 3AJ, ENGLAND SN 0885-4513 J9 BIOTECHNOL APPL BIOC JI Biotechnol. Appl. Biochem. PD FEB PY 2001 VL 33 BP 7 EP 16 DI 10.1042/BA20000044 PN 1 PG 10 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 404TT UT WOS:000167118100002 PM 11171031 ER PT J AU Sadana, A Vo-Dinh, T AF Sadana, A Vo-Dinh, T TI A kinetic analysis using fractals of cellular analyte-receptor binding and dissociation SO BIOTECHNOLOGY AND APPLIED BIOCHEMISTRY LA English DT Article DE affinity; cell-surface reaction kinetics; predictive relations ID ANTIGEN-ANTIBODY BINDING; SURFACE-PLASMON RESONANCE; MASS-TRANSPORT; BIOSENSOR APPLICATIONS; IMMOBILIZED ANTIBODY; OPTICAL BIOSENSOR; EXTERNAL DIFFUSION; RATE COEFFICIENT; HIV-1 PROTEASE; LIMITATIONS AB A fractal analysis is presented for cellular analyte-receptor binding and dissociation kinetics using a biosensor. Data taken from the literature may be modelled, in the case of binding, using a single-fractal analysis or a dual-fractal analysis. The dual-fractal analysis represents a change in the binding mechanism as the reaction progresses on the surface. The predictive relationship developed for the equilibrium constant, K (affinity which is equal to k(d)/k(1 or 2)), as a function of the analyte concentration is of particular value since it provides a means by which the affinity may be manipulated. This should be of assistance in cell-surface reactions, drug-candidate optimization and for the design of immunodiagnostic devices. Relationships are also presented for the binding and dissociation rate coefficients as a function of their corresponding fractal dimension, D-f or the degree of heterogeneity that exists on the surface, and the analyte concentration in solution. When analyte-receptor binding or dissociation is involved, an increase in the heterogeneity on the surface (increase in D-f or D-fd as the case may be) leads to an increase in the binding and the dissociation rate coefficients. It is suggested that an increase in the degree of heterogeneity on the surface leads to an increase in the turbulence on the surface owing to the irregularities on the surface, This turbulence promotes mixing, minimizes diffusional limitations and leads subsequently to an increase in the binding and the dissociation rate coefficients. The binding and dissociation rate coefficients are rather sensitive to the degree of heterogeneity, D-f and D-fd, respectively, that exists on the biosensor surface, The heterogeneity on the surface in general affects the binding and dissociation rate coefficients differently. In general, the analyte concentration in solution has a mild affect on the fractal dimension for binding or the fractal dimension for dissociation. This is indicated by the low values of the exponent in the predictive relationships developed. C1 Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. Univ Mississippi, Dept Chem Engn, University, MS 38677 USA. RP Vo-Dinh, T (reprint author), Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. NR 43 TC 5 Z9 5 U1 0 U2 0 PU PORTLAND PRESS PI LONDON PA 59 PORTLAND PLACE, LONDON W1N 3AJ, ENGLAND SN 0885-4513 J9 BIOTECHNOL APPL BIOC JI Biotechnol. Appl. Biochem. PD FEB PY 2001 VL 33 BP 17 EP 28 DI 10.1042/BA20000048 PN 1 PG 12 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 404TT UT WOS:000167118100003 PM 11171032 ER PT J AU Willig, TN Breton-Gorius, J Elbim, C Mignotte, V Kaplan, C Mollicone, R Pasquier, C Filipe, A Mielot, F Cartron, JP Gougerot-Pocidalo, MA Debili, N Guichard, J Deommergues, JP Mohandas, N Tchernia, G AF Willig, TN Breton-Gorius, J Elbim, C Mignotte, V Kaplan, C Mollicone, R Pasquier, C Filipe, A Mielot, F Cartron, JP Gougerot-Pocidalo, MA Debili, N Guichard, J Deommergues, JP Mohandas, N Tchernia, G TI Macrothrombocytopenia with abnormal demarcation membranes in megakaryocytes and neutropenia with a complete lack of sialyl-Lewis-X antigen in leukocytes - a new syndrome? SO BLOOD LA English DT Article ID BERNARD-SOULIER-SYNDROME; GLYCOPROTEIN-IB-ALPHA; MUTATION; NEUTROPHILS; VARIANT; CELLS; IX AB A new megathrombocytopenic syndrome with giant platelets in peripheral blood and severe thrombocytopenia was diagnosed in a 4-month-old boy. His clinical course included repeated hemorrhagic incidents leading to death at age 37 months. Bone marrow ultrastructural analysis revealed numerous dystrophic megakaryocytes with giant membrane complexes. Although these features were similar to those described for megakaryocytes in mice lacking the gene for transcription factor p45-NF-E2, no abnormalities in the p45-NF-E2 gene could be documented. Platelet membrane analysis showed a reduction in glycoprotein (GP) Ib, but normal content of GPIIb and GPIIIa. Analysis of genes encoding for GPIb alpha and beta, GPV, and GPIX ruled out the possibility that the observed platelet abnormality is a variant of Bernard-Soulier syndrome. A moderate neutropenia was associated with a complete lack of expression of sialyl-Lewis-X on the surface of polymorphonuclear neutrophils. A common defect in posttranslational modification of glycoproteins could account for the diverse cellular abnormalities. (C) 2001 by The American Society of Hematology. C1 CHU Kremlin Bicetre, Serv Pediat, Assistance Publ Hop Paris, Le Kremlin Bicetre, France. CHU Kremlin Bicetre, Lab Hematol Immunol & Cytogenet, Assistance Publ Hop Paris, Le Kremlin Bicetre, France. INSERM U362, Villejuif, France. INSERM U504, Villejuif, France. Hop Bichat Claude Bernard, Serv Hematol & Immunol Biol, Paris, France. Hop Bichat Claude Bernard, INSERM U479, Paris, France. INTS, Lab Immunol Plaquettaire, Paris, France. INTS, INSERM U76, Paris, France. CHU Bichat, INSERM U479, Paris, France. RP Mohandas, N (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Bldg 74-157,1 Cyclotron Rd, Berkeley, CA 94720 USA. EM mnarla@lbl.gov NR 17 TC 22 Z9 23 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 FEB 1 PY 2001 VL 97 IS 3 BP 826 EP 828 DI 10.1182/blood.V97.3.826 PG 3 WC Hematology SC Hematology GA 397LV UT WOS:000166697900035 PM 11157507 ER PT J AU Asanuma, H Ishimoto, M Jones, RH Phillips, WS Niitsuma, H AF Asanuma, H Ishimoto, M Jones, RH Phillips, WS Niitsuma, H TI A variation of the collapsing method to delineate structures inside a microseismic cloud SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID EARTHQUAKES AB We describe a modification to the collapsing method, a technique that aims to find the simplest structures in a cloud of microearthquakes by utilizing the statistical uncertainties in the data. In the modified collapsing method, the movements of the locations are dependent on the shape of the distribution of the locations within the confidence ellipsoid, and not just the position of the center of gravity, as is the case in the original method. Additionally, whereas the original collapsing method implicitly assumes that all locations belong to point structures, in this modified version three types of structure are considered: point, line, and plane. Principal component analysis of the locations is used to evaluate to which type of structure each location most probably belongs. The modified technique has been applied to microseismic events associated with hydraulic stimulation at the Fenton Hill HDR Field, New Mexico, and known small-scale structures were imaged. C1 Tohoku Univ, Grad Sch Engn, Sendai, Miyagi 980, Japan. ABB Offshore Syst, Penryn, England. Univ Calif Los Alamos Natl Lab, Los Alamos Seism Res Ctr, Los Alamos, NM 87545 USA. RP Asanuma, H (reprint author), Tohoku Univ, Grad Sch Engn, Sendai, Miyagi 980, Japan. NR 8 TC 4 Z9 4 U1 0 U2 0 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD FEB PY 2001 VL 91 IS 1 BP 154 EP 160 DI 10.1785/0120000063 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 415KM UT WOS:000167720600013 ER PT J AU Wiese, C Gauny, SS Liu, WC Cherbonnel-Lasserre, CL Kronenberg, A AF Wiese, C Gauny, SS Liu, WC Cherbonnel-Lasserre, CL Kronenberg, A TI Different mechanisms of radiation-induced loss of heterozygosity in two human lymphoid cell lines from a single donor SO CANCER RESEARCH LA English DT Article ID THYMIDINE KINASE LOCUS; DOUBLE-STRAND BREAK; DIPLOID HUMAN-LYMPHOBLASTS; HUMAN RAD51 PROTEIN; HOMOLOGOUS RECOMBINATION; MITOTIC RECOMBINATION; HPRT LOCUS; HYPOXANTHINE PHOSPHORIBOSYLTRANSFERASE; RESTRICTION ENDONUCLEASES; CHROMOSOMAL-ABERRATIONS AB Allelic loss is an important mutational mechanism in human carcinogenesis. Loss of heterozygosity (LOH) at an autosomal locus is one outcome of the repair of DNA double-strand breaks (DSBs) and can occur by deletion or by mitotic recombination, We report that mitotic recombination between homologous chromosomes occurred in human lymphoid cells exposed to densely ionizing radiation. We used cells derived from the same donor that express either normal TP53 (TK6 cells) or homozygous mutant TP53 (WTK1 cells) to assess the influence of TP53 on radiation-induced mutagenesis, Expression of mutant TP53 (Met 237 Ile) was associated with a small increase in mutation frequencies at the hemizygous HPRT (hypoxanthine phosphoribosyl transferase) Locus, but the mutation spectra were unaffected at this locus, In contrast, WTK1 cells (mutant TP53) were 30-fold more susceptible than TK6 cells (wild-type TP53) to radiation-induced mutagenesis at the TK1 (thymidine kinase) locus. Gene dosage analysis combined with microsatellite marker analysis showed that the increase in TK1 mutagenesis in WTK1 cells could be attributed, in part, to mitotic recombination, The microsatellite marker analysis over a 64-cM region on chromosome 17q indicated that the recombinational events could initiate at different positions between the TK1 locus and the centromere. Virtually all of the recombinational LOH events extended beyond the TK1 locus to the most telomeric marker. In general, longer LOH tracts were observed in mutants from WTK1 tells than in mutants from TK6 cells. Taken together, the results demonstrate that the incidence of radiation-induced mutations is dependent on the genetic background of the cell at risk, on the locus examined, and on the mechanisms for mutation available at the locus of interest. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Cellular & Mol Biol, Div Life Sci, Berkeley, CA 94720 USA. Harvard Univ, Sch Med, Boston, MA 02115 USA. RP Kronenberg, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Cellular & Mol Biol, Div Life Sci, 1 Cyclotron Rd,MS 70A-1118, Berkeley, CA 94720 USA. NR 72 TC 28 Z9 30 U1 0 U2 4 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 FEB 1 PY 2001 VL 61 IS 3 BP 1129 EP 1137 PG 9 WC Oncology SC Oncology GA 403AJ UT WOS:000167020100058 PM 11221843 ER PT J AU Holbrook, SR Holbrook, EL Walukiewicz, HE AF Holbrook, SR Holbrook, EL Walukiewicz, HE TI Crystallization of RNA SO CELLULAR AND MOLECULAR LIFE SCIENCES LA English DT Review DE RNA crystallization; X-ray crystallography; RNA crystal structure; sparse matrix crystallization; X-ray diffraction ID 5S RIBOSOMAL-RNA; PHENYLALANINE TRANSFER-RNA; CRYSTAL-STRUCTURE; THERMUS-FLAVUS; ANGSTROM RESOLUTION; CAPILLARY ELECTROPHORESIS; 3-DIMENSIONAL STRUCTURE; PRELIMINARY DIFFRACTION; HAMMERHEAD RIBOZYME; TERTIARY STRUCTURE AB Even as the number of RNA structures determined and under study multiplies, the critical step in X-ray diffraction analysis, growth of single well-ordered crystals, remains at the boundary between art and science. Recent advances in methods of RNA synthesis, purification, and characterization, as well as empirical and technical improvements in crystallization techniques, the development of cryo-crystallography, and the wider availability of bright, tunable, X-rays from synchrotron sources are improving the chances of obtaining RNA crystals suitable for X-ray structural analysis. In this review, we summarize the current status of the design, preparation, purification, and analysis of RNA for crystallization and describe the latest approaches to obtaining diffraction-quality crystals. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Phys Biosci Div, Dept Biol Struct, Berkeley, CA 94720 USA. RP Holbrook, SR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Phys Biosci Div, Dept Biol Struct, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [GM 4921501] NR 67 TC 11 Z9 11 U1 0 U2 2 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 1420-682X J9 CELL MOL LIFE SCI JI Cell. Mol. Life Sci. PD FEB PY 2001 VL 58 IS 2 BP 234 EP 243 DI 10.1007/PL00000851 PG 10 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 415DX UT WOS:000167706500008 PM 11289305 ER PT J AU Papar, RA Scheihing, PE AF Papar, RA Scheihing, PE TI Achieving a more efficient chemical industry SO CHEMICAL PROCESSING LA English DT Article C1 Lawrence Berkeley Natl Lab, Washington, DC USA. RP Papar, RA (reprint author), Lawrence Berkeley Natl Lab, Washington, DC USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU PUTMAN PUBL CO PI CHICAGO PA 301 E ERIE STREET, CHICAGO, IL 60611 USA SN 0009-2630 J9 CHEM PROCESS JI Chem. Process. PD FEB PY 2001 VL 64 IS 2 BP 51 EP 53 PG 3 WC Engineering, Chemical SC Engineering GA 404AM UT WOS:000167075300009 ER PT J AU Casale, GP Singhal, M Bhattacharya, S RamaNathan, R Roberts, KP Barbacci, DC Zhao, J Jankowiak, R Gross, ML Cavalieri, EL Small, GJ Rennard, SI Mumford, JL Shen, ML AF Casale, GP Singhal, M Bhattacharya, S RamaNathan, R Roberts, KP Barbacci, DC Zhao, J Jankowiak, R Gross, ML Cavalieri, EL Small, GJ Rennard, SI Mumford, JL Shen, ML TI Detection and quantification of depurinated benzol[alpha] pyrene-adducted DNA bases in the urine of cigarette smokers and women exposed to household coal smoke SO CHEMICAL RESEARCH IN TOXICOLOGY LA English DT Article ID WHITE BLOOD-CELLS; POLYCYCLIC AROMATIC-HYDROCARBONS; LUNG-CANCER MORTALITY; MOUSE SKIN; XUAN-WEI; CAPILLARY ELECTROPHORESIS; MOLECULAR EPIDEMIOLOGY; FLUOROMETRIC ASSAY; IN-VITRO; BENZOPYRENE AB Polycyclic aromatic hydrocarbons (PAM) are metabolized to electrophiles that can bind to DNA bases and destabilize the N-glycosyl bond, causing rapid depurination of the adducted bases. Recent studies support depurination of DNA as a mechanism central to the genesis of H-ras mutations in PAM-treated mouse skin. Depurinating adducts account for 71.% of all DNA adducts formed in mouse skin treated with benzo[a]pyrene (BP). This study analyzed urine of cigarette smokers, coal smoke-exposed women, and nonexposed controls for the presence and quantities of the depurinated BP-adducted DNA bases, 7-(benzo[a]pyren-6-yl)guanine (BP-6-N7Gua) and 7-(benzo[a]pyren-6-yl)adenine (BP-6-N7Ade). Since these adducted bases originate from reaction of the BP radical cation with double-stranded DNA and not with RNA or denatured DNA, their presence in urine is indicative of DNA damage. Urine samples were fractionated by a combination of SepPak extraction and reverse-phase HPLC, and then analyzed by tandem mass spectrometry and capillary electrophoresis with laser-induced fluorescence. BP-adducted bases were detected in the urine from three of seven cigarette smokers and three of seven women exposed to coal smoke, but were not detected in urine from the 13 control subjects. Concentrations were estimated to be 60-340 and 0.1-0.6 fmol/mg of creatinine equivalent of urine for coal smoke-exposed women (maximum possible BP intake of ca. 23 000 ng/day) and cigarette smokers (BP intake of ca. 800 ng/day), respectively, exhibiting a sensitive response to BP exposures. BP-6-N7Gua was present at ca. 20-300 times the concentration of BP-6-N7Ade in the urine of coal smoke-exposed women, but was not detected in the urine of cigarette smokers. This difference may be due to the remarkably different BP exposures experienced by the two groups of PAM-exposed individuals. These results justify more extensive studies of depurinated BP-adducted DNA bases as potential biomarkers of PAM-associated cancer risk. C1 Univ Nebraska, Med Ctr, Eppley Inst Res Canc, Omaha, NE 68198 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, US Dept Energy, Ames, IA 50011 USA. Univ Nebraska, Med Ctr, Omaha, NE 68198 USA. US EPA, Res Triangle Pk, NC 27711 USA. RP Casale, GP (reprint author), Univ Nebraska, Med Ctr, Eppley Inst Res Canc, 986805, Omaha, NE 68198 USA. FU NCI NIH HHS [2 PO1 CA49210]; NCRR NIH HHS [P41RR00954] NR 46 TC 57 Z9 58 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0893-228X J9 CHEM RES TOXICOL JI Chem. Res. Toxicol. PD FEB PY 2001 VL 14 IS 2 BP 192 EP 201 DI 10.1021/tx000012y PG 10 WC Chemistry, Medicinal; Chemistry, Multidisciplinary; Toxicology SC Pharmacology & Pharmacy; Chemistry; Toxicology GA 405FM UT WOS:000167147500006 PM 11258968 ER PT J AU Lang, DP Alam, TM Bencoe, DN AF Lang, DP Alam, TM Bencoe, DN TI Solid-state (31)p/Al-27 and P-31/Na-23 TRAPDOR NMR investigations of the phosphorus environments in sodium aluminophosphate glasses SO CHEMISTRY OF MATERIALS LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; ECHO DOUBLE-RESONANCE; HETERONUCLEAR DIPOLAR INTERACTIONS; CROSS-POLARIZATION NMR; ANGLE-SPINNING NMR; P-31 MAS NMR; PHOSPHATE-GLASSES; MAGIC-ANGLE; ALUMINOSILICATE GLASSES; INTERNUCLEAR DISTANCES AB Solid-state (31)p/Al-27 and (31)p/Na-23 TRAPDOR NMR experiments have been used to investigate the spatial distribution of aluminum and sodium cations with respect to the phosphate backbone for a Series of sodium aluminophosphate glasses, xAl(2)O(4). 50Na(2)O (50-x)P2O5 (0 less than or equal to x less than or equal to 17.5). From the (31)p/Al-27 and (31)p/Na-23 TRAPDOR data gathered, information about the medium-range order in these glasses was obtained. The expanded data allow for better identification and interpretation of the new resonances observed in the P-31 MAS NMR spectra with the addition of aluminum. The results of these experiments show that the sodium phosphate distribution remains relatively unchanged for the glass series and that the addition of aluminum occurs primarily through the modification of the phosphate tetrahedral backbone in the melt. C1 Sandia Natl Labs, Organ Mat Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Dept Mat Proc, Adv Mat Lab, Albuquerque, NM 87106 USA. RP Sandia Natl Labs, Organ Mat Dept, POB 5800, Albuquerque, NM 87185 USA. NR 56 TC 37 Z9 37 U1 2 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 EI 1520-5002 J9 CHEM MATER JI Chem. Mat. PD FEB PY 2001 VL 13 IS 2 BP 420 EP 428 DI 10.1021/cm000717l PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 405CG UT WOS:000167139200032 ER PT J AU Ponder, SM Darab, JG Bucher, J Caulder, D Craig, I Davis, L Edelstein, N Lukens, W Nitsche, H Rao, LF Shuh, DK Mallouk, TE AF Ponder, SM Darab, JG Bucher, J Caulder, D Craig, I Davis, L Edelstein, N Lukens, W Nitsche, H Rao, LF Shuh, DK Mallouk, TE TI Surface chemistry and electrochemistry of supported zerovalent iron nanoparticles in the remediation of aqueous metal contaminants SO CHEMISTRY OF MATERIALS LA English DT Article ID ZERO-VALENT IRON; AMORPHOUS ALLOY PARTICLES; SUBSURFACE REMEDIATION; CHROMATE REDUCTION; TRICHLOROETHYLENE; DECHLORINATION; DEGRADATION; TCE AB The microstructure, physical characteristics, corrosion behavior, and reactivity of zerovalent iron nanoparticles synthesized on a support (primarily a nonporous, hydrophobic polymer resin) were studied. The remediation of groundwater by zerovalent iron in in situ permeable reactive barriers relies on the redox reaction between metallic iron and a reducible contaminant. Decreasing the size of the iron particles and dispersing them on a support increases the specific surface area of the iron, as well as the ratio of surface to bulk iron atoms, and should thereby increase both the reaction rate and the fraction of iron atoms available for the reaction. Borohydride reduction of aqueous ferrous sulfate gives supported iron nanoparticles, 10-30 nm in diameter, which consist of 85% zerovalent iron by weight. These materials ("ferragels") are stable in air and have corrosion behavior comparable to iron filings. Interestingly, the presence or absence of a support, as well as the boron remaining from the borohydride reduction process, influences the electrochemical corrosion rate of the composite materials. Supported and unsupported zerovalent iron nanoparticles are superior to iron filings in both terms of initial rates of reduction and total moles of contaminants (Cr(VI), Pb(II), TcO(4)(-)) reduced per mole of iron. The enhanced reactivity and passive corrosion behavior of these materials should make them good candidates for use in permeable reactive barriers. C1 Penn State Univ, Dept Chem, University Pk, PA 16802 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Mallouk, TE (reprint author), Penn State Univ, Dept Chem, University Pk, PA 16802 USA. EM tom@chem.psu.edu RI Mallouk, Thomas/K-7391-2012; OI Mallouk, Thomas/0000-0003-4599-4208; Craig, Ian/0000-0003-4481-3700 NR 33 TC 162 Z9 172 U1 10 U2 84 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 FEB PY 2001 VL 13 IS 2 BP 479 EP 486 DI 10.1021/cm000288r PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 405CG UT WOS:000167139200042 ER PT J AU Damm, CJ Lucas, D Sawyer, RF Koshland, CP AF Damm, CJ Lucas, D Sawyer, RF Koshland, CP TI Excimer laser fragmentation-fluorescence spectroscopy as a method for monitoring ammonium nitrate and ammonium sulfate particles SO CHEMOSPHERE LA English DT Article; Proceedings Paper CT 6th International Congress on Toxic Combustion By-Products CY JUN 27-30, 1999 CL UNIV KARLSRUHE, KARLSRUHE, GERMANY HO UNIV KARLSRUHE DE aerosol measurement; air pollution; combustion; diagnostics AB Excimer laser fragmentation-fluorescence spectroscopy (ELFFS) is shown to be an effective detection strategy for ammonium nitrate and ammonium sulfate particles at atmospheric pressure and room temperature. Following photofragmentation of the ammonium salt particle, fluorescence of the NH fragment is observed at 336 nm. The fluorescence signal is shown to depend linearly on particle surface area for laser intensities varying from 1.2 x 10(8) to 6 x 10(8) W/cm(2). The 100 shot (1 s) detection limits for ammonium nitrate range from 20 ppb for 0.2 mum particles to 125 ppb for 0.8 pm particles, where these concentrations are expressed as moles of ammonium ion per mole of air. For ammonium sulfate, the 100 shot (1 s) detection limits vary from 60 ppb for 0.2 mum particles to 500 ppb for 1 mum particles. These detection limits are low enough to measure ammonium salt particles that form in the exhaust of combustion processes utilizing ammonia injection as a nitric oxide control strategy. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. RP Lucas, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, MS 70-108B, Berkeley, CA 94720 USA. RI Sawyer, Robert/B-5013-2014 FU NIEHS NIH HHS [P42-ES04705] NR 16 TC 10 Z9 10 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD FEB-MAR PY 2001 VL 42 IS 5-7 BP 655 EP 661 DI 10.1016/S0045-6535(00)00239-3 PG 7 WC Environmental Sciences SC Environmental Sciences & Ecology GA 401VW UT WOS:000166950200025 PM 11219691 ER PT J AU Brown, AL Dayton, DC Nimlos, MR Daily, JW AF Brown, AL Dayton, DC Nimlos, MR Daily, JW TI Characterization of biomass pyrolysis vapors with molecular beam, single photon ionization time-of-flight mass spectrometry SO CHEMOSPHERE LA English DT Article; Proceedings Paper CT 6th International Congress on Toxic Combustion By-Products CY JUN 27-30, 1999 CL UNIV KARLSRUHE, KARLSRUHE, GERMANY HO UNIV KARLSRUHE DE aspen; polystyrene; cellulose; fragmentation ID MULTIPHOTON IONIZATION; CELLULOSE PYROLYSIS; SUPERSONIC BEAM; LEVOGLUCOSAN; RESOLUTION; CONVERSION; GENERATION; RELEASE AB A single photon ionization, molecular beam sampling, reflection time-of-flight mass spectrometer (SPI/MBTOFMS) has been developed and used to study pyrolysis products from a selection of biomass materials. Spectra are characterized by high resolution and decreased fragmentation compared to electron-impact ionization mass spectra from related molecular beam mass spectrometer systems equipped with quadrupole mass analyzers. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Colorado, Dept Mech Engn, Ctr Combust Res, Boulder, CO 80309 USA. RP Dayton, DC (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd,MS 3322, Golden, CO 80401 USA. NR 29 TC 31 Z9 31 U1 0 U2 21 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD FEB-MAR PY 2001 VL 42 IS 5-7 BP 663 EP 669 DI 10.1016/S0045-6535(00)00240-X PG 7 WC Environmental Sciences SC Environmental Sciences & Ecology GA 401VW UT WOS:000166950200026 PM 11219692 ER PT J AU Higgins, B Thomson, MJ Lucas, D Koshland, CP Sawyer, RF AF Higgins, B Thomson, MJ Lucas, D Koshland, CP Sawyer, RF TI An experimental and numerical study of the thermal oxidation of chlorobenzene SO CHEMOSPHERE LA English DT Article; Proceedings Paper CT 6th International Congress on Toxic Combustion By-Products CY JUN 27-30, 1999 CL UNIV KARLSRUHE, KARLSRUHE, GERMANY HO UNIV KARLSRUHE ID GAS-PHASE; COMBUSTION; PATHWAYS; RADICALS; BENZENE; TOLUENE; OXYGEN; FLAMES; H-2 AB A combustion-driven flow reactor was used to examine the formation of chlorinated and non-chlorinated species from the thermal oxidation of chlorobenzene under post-flame conditions. Temperature varied from 725 to 1000 K, while the equivalence ratio was held constant at 0.5. Significant quantities of chlorinated intermediates, vinyl chloride and chlorophenol, were measured. A dominant C-Cl scission destruction pathway seen in pyrolytic studies was not observed. Instead, hydrogen-abstraction reactions prevailed, leading to high concentrations of chlorinated byproducts. The thermal oxidation of benzene was also investigated for comparison. Chemical kinetic modeling of benzene and chlorobenzene was used to explore reaction pathways. Two chlorobenzene models were developed to test the hypothesis that chlorobenzene oxidation follows a GO-expulsion breakdown pathway similar to that of benzene. For the temperatures and equivalence ratio studied, hydrogen abstraction by hydroxyl radicals dominates the initial destruction of both benzene and chlorobenzene. Chlorinated byproducts (i.e., chlorophenol and vinyl chloride) were formed from chlorobenzene oxidation in similar quantities and at similar temperatures to their respective analogue formed during benzene oxidation (i.e., phenol and ethylene). (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Calif Polytech State Univ San Luis Obispo, Dept Mech Engn, San Luis Obispo, CA 93407 USA. Univ Toronto, Toronto, ON, Canada. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Higgins, B (reprint author), Calif Polytech State Univ San Luis Obispo, Dept Mech Engn, San Luis Obispo, CA 93407 USA. RI Sawyer, Robert/B-5013-2014 NR 32 TC 10 Z9 11 U1 1 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD FEB-MAR PY 2001 VL 42 IS 5-7 BP 703 EP 717 DI 10.1016/S0045-6535(00)00245-9 PG 15 WC Environmental Sciences SC Environmental Sciences & Ecology GA 401VW UT WOS:000166950200031 PM 11219697 ER PT J AU Franklin, PM Koshland, CP Lucas, D Sawyer, RF AF Franklin, PM Koshland, CP Lucas, D Sawyer, RF TI Evaluation of combustion by-products of MTBE as a component of reformulated gasoline SO CHEMOSPHERE LA English DT Article; Proceedings Paper CT 6th International Congress on Toxic Combustion By-Products CY JUN 27-30, 1999 CL UNIV KARLSRUHE, KARLSRUHE, GERMANY HO UNIV KARLSRUHE DE automotive emissions; methyl tertiary-butyl ether; fuel oxygenates; reformulated gasoline (RFG) ID TERT-BUTYL ETHER; SPECIATED HYDROCARBON EMISSIONS; MOTOR-VEHICLE EMISSIONS; TEMPERATURE OXIDATION; DIMETHYL ETHER; FLOW REACTOR; METHYL; IMPACT; PYROLYSIS; CATALYST AB Methyl tertiary-butyl ether (MTBE) is a gasoline oxygenate that is widely used throughout the US and Europe as an octane-booster and as a means of reducing automotive carbon monoxide (CO) emissions. The combustion by-products of pure MTBE have been evaluated in previous laboratory studies, but little attention has been paid to the combustion by-products of MTBE as a component of gasoline, MTBE is often used in reformulated gasoline (RFG), which has chemical and physical characteristics distinct from conventional gasoline, The formation of MTBE by-products in RFG is not well-understood, especially under "worst-case" vehicle emission scenarios such as fuel-rich operations, cold-starts or malfunctioning emission control systems, conditions which have not been studied extensively, Engine-out automotive dynamometer studies have compared RFG with MTBE to non-oxygenated RFG, Their findings suggest that adding MTBE to reformulated gasoline does not impact the high temperature flame chemistry in cylinder combustion processes. Comparison of tailpipe and exhaust emission studies indicate that reactions in the catalytic converter are quite effective in destroying most hydrocarbon MTBE by-product species. Since important reaction by-products are formed in the post-flame region, understanding changes in this region will contribute to the understanding of fuel-related changes in emissions, (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Sch Publ Hlth, Energy & Resources Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. RP Franklin, PM (reprint author), Univ Calif Berkeley, Sch Publ Hlth, Energy & Resources Grp, 310 Barrows Hall 3050, Berkeley, CA 94720 USA. RI Sawyer, Robert/B-5013-2014 NR 39 TC 14 Z9 15 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD FEB-MAR PY 2001 VL 42 IS 5-7 BP 861 EP 872 DI 10.1016/S0045-6535(00)00261-7 PG 12 WC Environmental Sciences SC Environmental Sciences & Ecology GA 401VW UT WOS:000166950200047 PM 11219713 ER PT J AU Fischer, P Mullen, J AF Fischer, P Mullen, J TI Filter-based stabilization of spectral element methods SO COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE I-MATHEMATIQUE LA English DT Article ID NAVIER-STOKES EQUATIONS; VISCOSITY; DIFFUSION AB We present a simple filtering procedure for stabilizing the spectral element method (SEM) for the unsteady advection-diffusion and Navier-Stokes equations. A number of example applications are presented, along with basic analysis for the advection-diffusion case. (C) 2001 Academie des sciences/Editions scientifiques et medicales Elsevier SAS. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Worcester Polytech Inst, Comp & Commun Ctr, Worcester, MA 01609 USA. RP Fischer, P (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 83 Z9 84 U1 1 U2 2 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 0764-4442 J9 CR ACAD SCI I-MATH JI Comptes Rendus Acad. Sci. Ser. I-Math. PD FEB 1 PY 2001 VL 332 IS 3 BP 265 EP 270 DI 10.1016/S0764-4442(00)01763-8 PG 6 WC Mathematics SC Mathematics GA 412HC UT WOS:000167548100016 ER PT J AU McNab, WW AF McNab, WW TI A Monte Carlo simulation method for assessing biotransformation effects on groundwater fuel hydrocarbon plume lengths SO COMPUTERS & GEOSCIENCES LA English DT Article DE analytical transport modeling; biodegradation; biotransformation; groundwater contamination; Monte Carlo analysis ID CONTAMINATED AQUIFER; MONOAROMATIC HYDROCARBONS; ANOXIC GROUNDWATER; SHALLOW SAND; BIODEGRADATION; BENZENE; DEGRADATION; OXIDATION; REDUCTION; SULFATE AB Biotransformation of dissolved groundwater hydrocarbon plumes emanating from leaking underground fuel tanks should, in principle, result in plume length stabilization over relatively short distances, thus diminishing the environmental risk. However, because the behavior of hydrocarbon plumes is usually poorly constrained at most leaking underground fuel tank sites in terms of release history, groundwater velocity, dispersion, as well as the biotransformation rate, demonstrating such a limitation in plume length is problematic. Biotransformation signatures in the aquifer geochemistry, most notably elevated bicarbonate, may offer a means of constraining the relationship between plume length and the mean biotransformation rate. In this study, modeled plume lengths and spatial bicarbonate differences among a population of synthetic hydrocarbon plumes, generated through Monte Carlo simulation of an analytical solute transport model, are compared to held observations from six underground storage tank (UST) sites at military bases in California. Simulation results indicate that the relationship between plume length and the distribution of bicarbonate is best explained by biotransformation rates that are consistent with ranges commonly reported in the literature. This finding suggests that bicarbonate can indeed provide an independent means for evaluating limitations in hydrocarbon plume length resulting from biotransformation. Published by Elsevier Science Ltd. C1 Lawrence Livermore Natl Lab, Environm Restorat Div, Livermore, CA 94551 USA. RP McNab, WW (reprint author), Lawrence Livermore Natl Lab, Environm Restorat Div, POB 808,L-530, Livermore, CA 94551 USA. EM mcnab1@llnl.gov NR 34 TC 4 Z9 4 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0098-3004 EI 1873-7803 J9 COMPUT GEOSCI-UK JI Comput. Geosci. PD FEB PY 2001 VL 27 IS 1 BP 31 EP 42 DI 10.1016/S0098-3004(00)00062-5 PG 12 WC Computer Science, Interdisciplinary Applications; Geosciences, Multidisciplinary SC Computer Science; Geology GA 365KP UT WOS:000089950700005 ER PT J AU Gullerud, AS Dodds, RH AF Gullerud, AS Dodds, RH TI MPI-based implementation of a PCG solver using an EBE architecture and preconditioner for implicit, 3-D finite element analysis SO COMPUTERS & STRUCTURES LA English DT Article DE element-by-element computation; Hughes-Winget preconditioner; parallel finite elements; message passing; conjugate gradient; domain decomposition; coloring algorithms ID ALGEBRAIC MULTIGRID SOLVER; SOLID MECHANICS; SOLUTION ALGORITHM; PARALLEL COMPUTERS; COMPUTATIONS; GROWTH; MEDIA AB This work describes a coarse-grain parallel implementation of a linear preconditioned conjugate gradient solver using an element-by-element architecture and preconditioner for computation. The solver, implemented within a nonlinear. implicit finite element code, uses an MPI-based message-passing approach to provide portable parallel execution on shared, distributed, and distributed-shared memory computers. The flexibility of the element-by-element approach permits a dual-level mesh decomposition; a coarse, domain-level decomposition creates a load-balanced domain for each processor for parallel computation, while a second level decomposition breaks each domain into blocks of similar elements (same constitutive model- order of integration, element type) for fine-grained parallel computation on each processor. The key contribution here is a new parallel implementation of the Hughes-Winget (HW) element-by-element preconditioner suitable for arbitrary, unstructured meshes. The implementation couples an unstructured dependency graph with a new balanced graph-coloring algorithm to schedule parallel computations within and across domains. The code also includes the diagonal preconditioner and a modern parallel (threaded) sparse direct solver for comparison, Three example problems with up to 158,000 elements and 180,000 nodes analyzed on an SGI/Gray Origin 2000 illustrate the parallel performance of the algorithms and preconditioners, Analyses with varying block sizes illustrate that the two-level decomposition improves overall execution speed with the block size tuned for the cache memory architecture of the executing platform. This implementation of the HW preconditioner shows reasonable parallel efficiency - typically 80'%, on 48 processors. Efficiency for the diagonal preconditioner is also high, with total speedups reaching 86% on 48 CPUs. Calculation of the tangent element stiffnesses shows superlinear speedups for each of the test problems, while the computation of strains/stresses/residual forces shows 80% parallel efficiency on 48 processors. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Illinois, Dept Civil Engn, Urbana, IL 61801 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dodds, RH (reprint author), Univ Illinois, Dept Civil Engn, Urbana, IL 61801 USA. EM r-dodds@uiuc.edu NR 60 TC 20 Z9 26 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-7949 EI 1879-2243 J9 COMPUT STRUCT JI Comput. Struct. PD FEB PY 2001 VL 79 IS 5 BP 553 EP 575 DI 10.1016/S0045-7949(00)00153-X PG 23 WC Computer Science, Interdisciplinary Applications; Engineering, Civil SC Computer Science; Engineering GA 394NH UT WOS:000166529800007 ER PT J AU Hay, BP Hancock, RD AF Hay, BP Hancock, RD TI The role of donor group orientation as a factor in metal ion recognition by ligands SO COORDINATION CHEMISTRY REVIEWS LA English DT Review DE molecular mechanics; metal ions; ligand design; amine; ether; complementarity preorganisation; amide ID CHELATE RING SIZE; ALKALINE-EARTH CATIONS; AQUEOUS-SOLUTION; CROWN-ETHERS; COORDINATION CHEMISTRY; MACROCYCLIC LIGANDS; STRUCTURAL CRITERIA; SELECTIVE LIGANDS; RATIONAL DESIGN; FORCE-FIELD AB Factors that control the metal ion complementarity of ligand architectures are described. These include cavity size, metal ion topography, and donor group orientation. Attention focuses on the last factor with a detailed discussion of how molecular mechanics has been used to investigate the role of donor group orientation in polyamine and polyether ligands, (C) 2001 Elsevier Science B.V, All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Power Engn, Provo, UT 84602 USA. RP Hay, BP (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 51 TC 108 Z9 111 U1 2 U2 18 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0010-8545 J9 COORDIN CHEM REV JI Coord. Chem. Rev. PD FEB PY 2001 VL 212 BP 61 EP 78 DI 10.1016/S0010-8545(00)00366-0 PG 18 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 404HC UT WOS:000167090500005 ER PT J AU Ashworth, SP Suenaga, M AF Ashworth, SP Suenaga, M TI Local calorimetry to measure ac losses in HTS conductors SO CRYOGENICS LA English DT Article; Proceedings Paper CT Workshop on AC Losses CY OCT 18-19, 2000 CL YOKOHAMA, JAPAN ID TRANSPORT CURRENTS; MAGNETIC-FIELDS; SUPERCONDUCTORS; TAPES AB We present an overview of the development and use of local calorimetry to determine ac losses in individual HTS conductors, in coils and high amperage multi-tape conductors. The practical aspects of this technique are fully described, alone, with suggestions for achieving the desired resolution in loss measurement. Our recently developed local calorimetry method has been shown to allow the straightforward determination of losses of an individual conductor in almost any combination of field and current and is not limited to simple sinusoidal waveforms. We have extended this technique to structures of conductors e.g. coils and tape arrays where the ac magnetic fields generated by the structure as a whole influence the losses of the individual conductors. In these structures the individual HTS tapes see a local 'applied' magnetic field generated by the structure and a 'self'-field due to the current flowing in the tape. The interaction of the various magnetic fields makes it extremely difficult to measure the losses in these structures using for example pick-up coils and a lock-in amplifier, but using our calorimetric technique we are able to measure the losses at specific locations within the coil or array. In this paper we present examples of loss measurements made, for example, at various positions on a simple solenoidal coil and the changes in losses as a multi-tape, high amperage conductor is assembled. The data of local losses obtained on small-scale models may allow the estimation and minimisation of losses in full-scale designs or may be used in the verification of numerical models. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Div Mat & Chem Sci, Upton, NY 11973 USA. RP Ashworth, SP (reprint author), Brookhaven Natl Lab, Div Mat & Chem Sci, Bldg 480,POB 5000, Upton, NY 11973 USA. NR 25 TC 27 Z9 28 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB PY 2001 VL 41 IS 2 BP 77 EP 89 DI 10.1016/S0011-2275(01)00051-0 PG 13 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 449BL UT WOS:000169664400003 ER PT J AU Dobson, JE Geelhoed, GW AF Dobson, JE Geelhoed, GW TI On the Chatelperronian/Aurignacian conundrum: One culture, multiple human morphologies? SO CURRENT ANTHROPOLOGY LA English DT Editorial Material ID CORRECTING ENDEMIC HYPOTHYROIDISM; MEDICAL INTERVENTION; SOCIAL-CONSEQUENCES C1 George Washington Univ, Med Ctr, Off Dean, Washington, DC 20037 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Dobson, JE (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 11 TC 4 Z9 4 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0011-3204 J9 CURR ANTHROPOL JI Curr. Anthropol. PD FEB PY 2001 VL 42 IS 1 BP 139 EP 140 DI 10.1086/318438 PG 2 WC Anthropology SC Anthropology GA 399KN UT WOS:000166810400006 ER PT J AU Boopathy, R Peters, R AF Boopathy, R Peters, R TI Enhanced biotransformation of trichloroethylene under mixed electron acceptor conditions SO CURRENT MICROBIOLOGY LA English DT Article ID CHLORINATED ALIPHATIC-HYDROCARBONS; REDUCTIVE DECHLORINATION; ORGANIC-COMPOUNDS; ANAEROBIC BIOTRANSFORMATION; METHANOGENIC CONDITIONS; INSITU BIORESTORATION; ENRICHMENT CULTURE; MODEL SIMULATIONS; DEGRADATION; BACTERIA AB The biotransformation of trichloroethylene (TCE) under various electron acceptor conditions was investigated by using enrichment cultures developed from the anaerobic digester sludge of Thibodaux sewage treatment plant. The results indicated that TCE was biotransformed under sulfate reducing, methanogenic, nitrate reducing, iron reducing, and fermenting conditions. However, the rates of TCE removal varied among the conditions studied. The fastest removal of TCE (100% removal in 9 days) was observed under mixed electron acceptor conditions, followed in order by methanogenic, fermenting, iron reducing, sulfate reducing, and nitrate reducing conditions. Under mixed electron acceptor conditions, the TCE was converted to ethene, which was further metabolized. Under sulfate and nitrate reducing conditions, the major metabolites produced from TCE metabolism were cis and trans dichloroethylene (DCE). Under methanogenic, iron reducing, and fermenting conditions, cis and trans DCE and ethene were produced from TCE metabolism. This study showed evidence for TCE metabolism in a mixed microbial population system similar to any contaminated field sites, where heterogeneous microbial population exists. C1 Nicholls State Univ, Dept Biol Sci, Thibodaux, LA 70310 USA. Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. RP Boopathy, R (reprint author), Nicholls State Univ, Dept Biol Sci, Thibodaux, LA 70310 USA. NR 41 TC 11 Z9 11 U1 0 U2 6 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0343-8651 J9 CURR MICROBIOL JI Curr. Microbiol. PD FEB PY 2001 VL 42 IS 2 BP 134 EP 138 DI 10.1007/s002840010192 PG 5 WC Microbiology SC Microbiology GA 392PD UT WOS:000166419100012 PM 11136136 ER PT J AU Da Costa, L Willig, TN Fixler, J Mohandas, N Tchernia, G AF Da Costa, L Willig, TN Fixler, J Mohandas, N Tchernia, G TI Diamond-Blackfan Anemia SO CURRENT OPINION IN PEDIATRICS LA English DT Review ID RIBOSOMAL-PROTEIN S19; NONIMMUNE HYDROPS; CHROMOSOME 19Q13; KIT GENES; C-KIT; MUTATIONS; ERYTHROPOIETIN; IDENTIFICATION; EXPRESSION; CHILDHOOD AB Diamond-Blackfan Anemia (DBA) is a rare, congenital hypoplastic anemia often diagnosed early in infancy. A moderate to severe aregenerative anemia is found in association with erythroblastopenia in an otherwise normocellular bone marrow. In 40% of these infants with DBA, diverse developmental abnormalities are also noted. A majority of patients with DBA respond to steroid therapy, Recent molecular studies have identified mutations in the gene encoding the ribosomal protein RPS19 on chromosome 19 in 25% of patients with DBA, In another subset of patients, linkage analysis has identified another locus on chromosome 8p in association with DBA. There are, however, other cases of DBA that are linked neither to the RPS19 gene nor to the locus on 8p, implying the involvement of yet-to-be-defined genetic defects in the cause of DBA, The pathogenesis of DBA is still to be fully defined and it is anticipated that further molecular studies will lead to a better understanding of this complex disease. (C) 2001 Lippincott Williams & Wilkins, Inc. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Hop Kremlin Bicetre, Hematol Lab, F-94275 Le Kremlin Bicetre, France. RP Da Costa, L (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Mailstop 74-157,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Brugnara, Carlo/A-8041-2010 OI Brugnara, Carlo/0000-0001-8192-8713 NR 46 TC 28 Z9 28 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1040-8703 J9 CURR OPIN PEDIATR JI CURR. OPIN. PEDIATR. PD FEB PY 2001 VL 13 IS 1 BP 10 EP 15 PG 6 WC Pediatrics SC Pediatrics GA 397YB UT WOS:000166725300002 PM 11176237 ER PT J AU Velappan, N Snodgrass, JL Hakovirta, JR Marrone, BL Burde, S AF Velappan, N Snodgrass, JL Hakovirta, JR Marrone, BL Burde, S TI Rapid identification of pathogenic bacteria by single-enzyme amplified fragment length polymorphism analysis SO DIAGNOSTIC MICROBIOLOGY AND INFECTIOUS DISEASE LA English DT Article ID MARKERS AB Despite major progress in their treatment and prevention, bacterial infections remain a significant cause of morbidity and mortality worldwide. In responding to a disease outbreak, rapid and accurate identification of the bacterial species involved is of paramount importance. Strain level discrimination is desirable to allow selection of treatment modalities, and in the case of a deliberate release, for identification of the source. Single-enzyme amplified fragment length polymorphism (SE-AFLP) analysis was used to perform species and strain identification of subgroup I Bacilli, Yersinia, Staphylococci and Escherichia coli. By careful selection of AFLP primers, it was possible to obtain reproducible and sensitive identification to strain level, even within the highly monomorphic species Bacillus anthracis. SE-AFLP fragments can be analyzed using standard gel electrophoresis, and can be easily scored by visual inspection, due to the low complexity of the fingerprint obtained by this method. These features make SE-AFLP suitable for use in either field or laboratory applications. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. USAF Acad, Colorado Springs, CO 80840 USA. RP Marrone, BL (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, POB 1663,MS M888, Los Alamos, NM 87545 USA. NR 6 TC 13 Z9 24 U1 1 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0732-8893 J9 DIAGN MICR INFEC DIS JI Diagn. Microbiol. Infect. Dis. PD FEB PY 2001 VL 39 IS 2 BP 77 EP 83 DI 10.1016/S0732-8893(00)00235-2 PG 7 WC Infectious Diseases; Microbiology SC Infectious Diseases; Microbiology GA 413LE UT WOS:000167613000002 PM 11248519 ER PT J AU Clark, ME Rose, KA Levine, DA Hargrove, WW AF Clark, ME Rose, KA Levine, DA Hargrove, WW TI Predicting climate change effects on Appalachian trout: Combining GIS and individual-based modeling SO ECOLOGICAL APPLICATIONS LA English DT Article DE brook and rainbow trout; geographic information system (GIS); global climate change; individual-based model; Oncorhynchus mykiss; Salvelinus fontinalis; southern Appalachian streams; temperature and flow gradients; watershed elevation zones ID POTENTIAL HABITAT LOSS; NATIVE BROOK TROUT; SALMO-TRUTTA L; RAINBOW-TROUT; SALVELINUS-FONTINALIS; BROWN TROUT; COLORADO STREAMS; SYMPATRIC BROOK; MOUNTAINS; TEMPERATURE AB We coupled an individual-based model of brook trout (Salvelinus fontinalis) and rainbow trout (Oncorhynchus mykiss) with a geographic information system (GIS) database to predict climate change effects on southern Appalachian stream populations. The model tracked individuals of both species through the daily processes of spawning, growth, feeding, mortality, and movement for 30 years in a stream reach consisting of connected pools, runs, and riffles. The southern Appalachian Plateau was divided into 101 watershed elevation band zones. Model simulations were performed for a representative stream reach of each stream order in each zone. Trout abundance was estimated by multiplying predicted trout densities (measured in number of trout per meter) by the total length of streams of each order in each watershed elevation zone. Three climate change scenarios were analyzed: temperature only (1.5-2.5 degreesC warmer stream temperatures); temperature and how (warmer stream temperatures and lower baseline flows with threefold higher peak hows); and temperature, flow, and mortality episodes (warmer stream temperatures, changed hows, and flow-related scouring of redds). Increased temperature alone resulted in increased abundances of brook and rainbow trout. The temperature-and-how scenario resulted in a complex mosaic of positive and negative changes in abundances in zones, but little change in total abundance. Addition of episodic mortality in the form of floods that scour redds and kill eggs and fry caused a net loss of rainbow trout. Predicted changes in habitat (based on simulation results and temperature alone) were, at best, weakly correlated with predicted changes in abundance. The coupling of individual-based models to GIS databases, in order to scale up environmental effects on individuals to regional population responses, offers a promising approach for regional assessments. C1 Iowa State Univ Sci & Technol, Dept Anim Ecol, Ames, IA 50011 USA. Louisiana State Univ, Coastal Fisheries Inst, Baton Rouge, LA 70803 USA. Louisiana State Univ, Dept Oceanog & Coastal Sci, Baton Rouge, LA 70803 USA. Oak Ridge Natl Lab, Computat Phys & Engn Div, Oak Ridge, TN 37831 USA. RP Clark, ME (reprint author), Univ Montana, Montana Cooperat Wildlife Res Unit, Missoula, MT 59812 USA. NR 55 TC 44 Z9 46 U1 2 U2 33 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 1051-0761 J9 ECOL APPL JI Ecol. Appl. PD FEB PY 2001 VL 11 IS 1 BP 161 EP 178 DI 10.2307/3061064 PG 18 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA 398GT UT WOS:000166749100014 ER PT J AU Luo, Y Medlyn, B Hui, D Ellsworth, D Reynolds, J Katul, G AF Luo, Y Medlyn, B Hui, D Ellsworth, D Reynolds, J Katul, G TI Gross primary productivity in Duke Forest: Modeling synthesis of CO2 experiment and eddy-flux data SO ECOLOGICAL APPLICATIONS LA English DT Article DE canopy; carbon sink or sequestration; Duke Forest, North Carolina (USA); forest; global change; gross primary productivity (GPP); loblolly pine; model; modeling; photosynthesis; Pinus taeda; stomatal conductance ID CARBON-DIOXIDE ENRICHMENT; ELEVATED ATMOSPHERIC CO2; PINUS-TAEDA L.; LOBLOLLY-PINE; LEAF NITROGEN; CANOPY; TEMPERATURE; PHOTOSYNTHESIS; ECOSYSTEMS; RESPONSES AB This study was designed to estimate gross primary productivity (GPP) in the Duke Forest at both ambient and elevated CO2 (ambient + 200 muL/L) concentrations using a physiologically based canopy model. The model stratified the canopy of loblolly pine (Pinus taeda L.) forest into six layers and estimated photosynthesis in each layer according to the Farquhar submodel coupled with the Ball-Berry stomatal conductance submodel. The model was parameterized with a suite of physiological measurements, including leaf area index (LAI), leaf nitrogen (N) concentration, photosynthesis-N relationships, and stomatal conductance. The model was Validated against measured leaf photosynthesis and canopy carbon (C) fluxes estimated from eddy-covariance measurements (ECM). Application of this model to simulate canopy C fixation from 28 August 1996, the onset of CO2 fumigation, to 31 December 1998 suggested that elevation of atmospheric [CO2] to ambient + 200 muL/L resulted in increase of canopy C fixation by 35% in 1996, 39% in 1997, and 43% in 1998. The modeled GPP and its response to elevated [CO2] were sensitive to parameter values of quantum yield of electron transport, leaf area index, and the vertical distribution of LAI within the canopy. Thus, further investigation on those parameters will help improve the precision of estimated ecosystem-scale C fluxes. Furthermore, comparison between the modeled and ECM-estimated canopy C fluxes suggested that soil moisture, in addition to air vapor pressure, controlled canopy photosynthesis during the drought period. C1 Univ Oklahoma, Dept Bot & Microbiol, Norman, OK 73019 USA. Inst Natl Rech Agron, Pierroton, Stn Rech Forestieres, Lab Ecophysiol & Nutr, F-33611 Gazinet, France. Brookhaven Natl Lab, Environm Biol & Instrumentat Div, Upton, NY 11973 USA. Duke Univ, Dept Bot, Durham, NC 27708 USA. Duke Univ, Sch Environm, Durham, NC 27708 USA. RP Luo, Y (reprint author), Univ Oklahoma, Dept Bot & Microbiol, Norman, OK 73019 USA. EM yluo@ou.edu RI Katul, Gabriel/A-7210-2008; Reynolds, James/G-6364-2010; OI Katul, Gabriel/0000-0001-9768-3693; Ellsworth, David/0000-0002-9699-2272; Medlyn, Belinda/0000-0001-5728-9827 NR 52 TC 60 Z9 68 U1 1 U2 14 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1990 M STREET NW, STE 700, WASHINGTON, DC 20036 USA SN 1051-0761 J9 ECOL APPL JI Ecol. Appl. PD FEB PY 2001 VL 11 IS 1 BP 239 EP 252 PG 14 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA 398GT UT WOS:000166749100020 ER PT J AU Finzi, AC Allen, AS DeLucia, EH Ellsworth, DS Schlesinger, WH AF Finzi, AC Allen, AS DeLucia, EH Ellsworth, DS Schlesinger, WH TI Forest litter production, chemistry, and decomposition following two years of free-air CO2 enrichment SO ECOLOGY LA English DT Article DE carbon dioxide; effects of elevated levels; decomposition; FACE (free-air CO2 enrichment); forest, southern United States; litter; nitrogen; nutrient cycling; nutrient-use efficiency; phosphorus; Pinus taeda; retranslocation efficiency ID ELEVATED ATMOSPHERIC CO2; CARBON-DIOXIDE; PINUS-TAEDA; NUTRIENT RESORPTION; PLANT-RESPONSES; USE EFFICIENCY; NITROGEN; SOIL; ECOSYSTEMS; QUALITY AB Increases in tree biomass may be an important sink for CO2 as the atmospheric concentration continues to increase. Tree growth in temperate forests is often limited by the availability of soil nutrients. To assess whether soil nutrient limitation will constrain forest productivity under high atmospheric CO2, we studied the changes in forest litter production and nutrient cycling in a maturing southern U.S, loblolly pine-hardwood forest during two years of free-air CO2 enrichment. The objective of this paper is to present data on the chemistry of green leaves and leaf litter, nutrient-retranslocation efficiency, aboveground litter production, whole-system nutrient-use efficiency, decomposition, and N availability in response to forest growth under elevated CO2. The chemical composition of green leaves and leaf litter was largely unaffected by elevated CO2. Green-leaf nitrogen (N) and phosphorus (P) concentrations were not significantly lower under elevated CO2. N and P retranslocation from green leaves did not increase under elevated CO2; therefore, leaf litter N and P concentrations were not significantly lower under elevated CO2. The concentrations of carbon, lignin, and total nonstructural carbohydrates in litter were not significantly different under elevated CO2. Total aboveground litterfall increased significantly with CO2 fumigation, The increase in litterfall was due to significant increases in loblolly pine leaf litter and bark production. The mass of leaves from deciduous species did not increase with CO2 fumigation, Whole-system nutrient-use efficiency (aboveground litterfall/nutrient content of litterfall) did not increase as a consequence of forest growth under elevated CO2, but N and P fluxes from vegetation to the forest floor increased significantly. During the second year of CO2 fumigation, the flux of N and P to the forest floor in litterfall increased by 20% and 34%, respectively. The rate of mass loss during one year of decomposition was unaffected by "litter type" (whether the litter was produced under ambient or elevated CO,), nor by the "site" of decomposition (whether the litter was decomposed in the ambient or elevated CO, plots). N was immobilized in litter during decomposition, whereas P was mineralized. There was no consistent effect of litter type or site on nutrient dynamics in decomposing litter. There was no significant effect of elevated CO2 on the pool size of inorganic N (NH4+ and NO3-) in the top 7.5 cm of mineral soil. The rate of net N mineralization and nitrification in mineral soil was not significantly different between treatment and control plots. Identifying the source of the nutrients lost in litterfall is critical to the long-term potential growth Stimulation of forests under elevated CO2. If the nutrients lost from biomass come from storage (e.g., the movement of nutrients from wood to leaves), then the increase in litter production should decrease over time as slowly replenished nutrient reserves are exhausted. If the nutrients lost in plant litter are replaced by uptake from soils, then it is possible (1) that trees acquire soil nutrients at a rate commensurate with growth stimulated by elevated CO2; and (2) that forest productivity will be stimulated by elevated CO2 in the long term. C1 Duke Univ, Dept Bot, Durham, NC 27708 USA. Univ Illinois, Dept Plant Biol, Urbana, IL 61801 USA. Duke Univ Div, Brookhaven Natl Lab, Nicholas Sch Environm, Durham, NC 27708 USA. RP Finzi, AC (reprint author), Boston Univ, Dept Biol, 5 Cummington St, Boston, MA 02215 USA. RI Finzi, Adrien/A-7017-2016; OI Finzi, Adrien/0000-0003-2220-4533; Ellsworth, David/0000-0002-9699-2272 NR 70 TC 137 Z9 152 U1 6 U2 76 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 0012-9658 J9 ECOLOGY JI Ecology PD FEB PY 2001 VL 82 IS 2 BP 470 EP 484 DI 10.2307/2679873 PG 15 WC Ecology SC Environmental Sciences & Ecology GA 403VX UT WOS:000167064100014 ER PT J AU Donepudi, VS Venkatachalapathy, R Ozemoyah, PO Johnson, CS Prakash, J AF Donepudi, VS Venkatachalapathy, R Ozemoyah, PO Johnson, CS Prakash, J TI Electrodeposition of copper from sulfate electrolytes - Effects of thiourea on resistivity and electrodeposition mechanism of copper SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID DEPOSITION AB Copper was electrodeposited from sulfate bath onto copper substrate over silicon wafer with titanium adhesive film and the resistivity was measured using a four-point probe method. The measured resistivities increased as thiourea concentration increased from 10(-6) to 10(-3) M and as the current density was increased from 1 to 50 mA/cm(2). The deposition potentials shifted to more negative values with an increase in thiourea concentration and cathodic overpolarization was observed in presence of thiourea, thereby suggesting chemisorption of thiourea on cathodic sites. Scanning electron micrographs show the presence of sulfur in the deposit when thiourea is present in the solution. The presence of thiourea in the deposit is suggestive of the reaction H2NCSNH2 + 2H(+) + 2e(-) --> NH4CN + H2S at electrolyte-electrode interfaces. This reaction can further lead to deleterious formation of copper sulfide in the deposit and a consequent increase in resistivity of electrodeposited copper. (C) 2001 The Electrochemical Society. C1 IIT, Dept Environm Chem & Engn, Chicago, IL 60616 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Donepudi, VS (reprint author), IIT, Dept Environm Chem & Engn, Chicago, IL 60616 USA. NR 10 TC 36 Z9 36 U1 0 U2 20 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 FEB PY 2001 VL 4 IS 2 BP C13 EP C16 DI 10.1149/1.1342144 PG 4 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 408KR UT WOS:000167325800006 ER PT J AU Kim, J Amine, K AF Kim, J Amine, K TI The effect of tetravalent titanium substitution in LiNi1-xTixO2 (0.025 <= x <= 0.2) system SO ELECTROCHEMISTRY COMMUNICATIONS LA English DT Article DE rechargeable lithium battery; cathode materials; lithium nickel oxides; layered compound; tetravalent titanium; substitution ID LINIO2; LICOO2 AB Layered LiNi1-xTixO2 (0.025 less than or equal to x less than or equal to 0.2) containing tetravalent titanium ions was prepared by solid-state reaction at 750 degreesC under an oxygen stream. The products show highly ordered and phase-pure layered compounds. The structural integrity of the materials could be preserved by substituting Ti4+ ions to prevent impurity Ni2+ migration into lithium sites. The LiNi1-xTixO2 (0.025 less than or equal to x less than or equal to 0.2) cathode exhibits high reversible capacities (up to 240 mA h/g) and excellent cyclability (over 100 cycles) in the range 4.3-2.8 V at a current density of 0.2 mA/cm(2) (C/5 rate). One composition, LiNi0.975Ti0.025O2 showed the highest reversible capacity and energy density of all known layered LiNiO2 or LiCoO2 materials. The novel concept of substitution of tetravalent titanium is proven to be promising. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, Argonne, IL 60439 USA. RP Kim, J (reprint author), Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Amine, Khalil/K-9344-2013 NR 18 TC 55 Z9 63 U1 2 U2 18 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1388-2481 J9 ELECTROCHEM COMMUN JI Electrochem. Commun. PD FEB PY 2001 VL 3 IS 2 BP 52 EP 55 DI 10.1016/S1388-2481(00)00151-X PG 4 WC Electrochemistry SC Electrochemistry GA 400NB UT WOS:000166877100002 ER PT J AU Monier, C Baca, AG Chang, PC Li, NY Hou, HQ Ren, F Pearton, SJ AF Monier, C Baca, AG Chang, PC Li, NY Hou, HQ Ren, F Pearton, SJ TI Pnp InGaAsN-based HBT with graded base doping SO ELECTRONICS LETTERS LA English DT Article ID HETEROJUNCTION AB A grading of the base doping concentration is used to establish an electric field in the base of a Pnp A1GaAs/InGaAsN heterojunction bipolar transistor (HBT). An improved peak current gain value (beta similar or equal to 60) is observed over a device with uniform base doping, due to better hole transport in the base. A cut-off frequency of 15GHz measured from a 3 x 12 mum(2) non-self aligned HBT demonstrates the practical impact the electric field has on the transit time across the base. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. EMCORE Corp, Emcore Photovolta, Albuquerque, NM 87123 USA. RP Monier, C (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 4 TC 17 Z9 18 U1 0 U2 0 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 FEB 1 PY 2001 VL 37 IS 3 BP 198 EP 199 DI 10.1049/el:20010136 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 404BY UT WOS:000167078600040 ER PT J AU Ma, YF Shortreed, MR Li, HL Huang, WH Yeung, ES AF Ma, YF Shortreed, MR Li, HL Huang, WH Yeung, ES TI Single-molecule immunoassay and DNA diagnosis SO ELECTROPHORESIS LA English DT Article DE DNA; immunoassay; capillary electrophoresis; single molecules ID FLUORESCENCE CORRELATION SPECTROSCOPY; LASER-INDUCED FLUORESCENCE; CAPILLARY-ELECTROPHORESIS; HYBRIDIZATION; DIGOXIN; INTERFACE; VIRUS; PHYCOERYTHRIN; ANEUPLOIDY; PROTEIN AB Many assays relevant to disease diagnosis are based on electrophoresis, where the migration velocity is used for distinguishing molecules of different size or charge. However, standard gel electrophoresis is not only slow but also insensitive. We describe a single-molecule imaging procedure to measure the electrophoretic mobilities of up to 100 000 distinct molecules every second. The results correlate well with capillary electrophoresis (CE) experiments and afford confident discrimination between normal (16.5 kbp) and abnormal (6.1 kbp) mitochondrial DNA fragments, or beta -phycoerythrin-labeled digoxigenin (BP-D) and its immunocomplex (anti-D-BP-D). This demonstrates that virtually all electrophoresis diagnostic protocols from slab gels to CE should be adaptable to single-molecule detection. This opens up the prossibility of screening single copies of DNA or proteins within single biological cells for disease markers without performing polymerase chain reaction (PCR) or other biological amplification. C1 Iowa State Univ, Ames Lab, USDOE, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), Iowa State Univ, Ames Lab, USDOE, Ames, IA 50011 USA. NR 41 TC 19 Z9 20 U1 2 U2 5 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD FEB PY 2001 VL 22 IS 3 BP 421 EP 426 DI 10.1002/1522-2683(200102)22:3<421::AID-ELPS421>3.0.CO;2-W PG 6 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 409AM UT WOS:000167362400008 PM 11258749 ER PT J AU Song, LG Liang, DH Kielescawa, J Liang, J Tjoe, E Fang, DF Chu, B AF Song, LG Liang, DH Kielescawa, J Liang, J Tjoe, E Fang, DF Chu, B TI DNA sequencing by capillary electrophoresis using copolymers of acrylamide and N,N-dimethyl-acrylamide SO ELECTROPHORESIS LA English DT Article DE DNA sequencing; acrylamide copolymers; dimethylacrylamide ID REPLACEABLE LINEAR POLYACRYLAMIDE; CROSS-LINKED POLYACRYLAMIDE; HUMAN GENOME PROJECT; ARRAY ELECTROPHORESIS; GEL-ELECTROPHORESIS; 1000 BASES; SEPARATION; FRAGMENTS; FLUORESCENCE; SCANNER AB Copolymers of acrylamide (AM) and N,N-dimethylacrylamide (DMA) with AM to DMA molar ratios of 3:1, 2:1 and 1:1 and molecular weights of about 2.2 MDa were synthesized. The polymers were tested as separation media in DNA sequencing analysis by capillary electrophoresis (CE). The dynamic coating ability of polydimethylacrylamide (PDMA) and the hydrophilicity of polyacrylamide (PAM) have been successfully combined in these random copolymers. A separation efficiency of over 10 million theoretical plates per meter has been reached by using the bare capillaries without the additional polymer coating step. Under optimized separation conditions for longer read length DNA sequencing, the separation ability of the copolymers decreased with decreasing AM to DMA molar ratio from 3:1, 2:1 and 1:1. In comparison with PAM, the copolymer with a 3:1 AM:DMA ratio showed a higher separation efficiency. By using a 2.5% w/v copolymer with 3:1 AM:DMA ratio, one base resolution of 0.55 up to 699 bases and 0.30 up to 963 bases have been achieved in about 80 min at ambient temperatures. C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Wheatley Sch, Old Westbury, NY USA. RP Chu, B (reprint author), SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. FU NHGRI NIH HHS [2R01HG 0138604]; NIAID NIH HHS [1R01 AI22222] NR 51 TC 33 Z9 33 U1 0 U2 4 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD FEB PY 2001 VL 22 IS 4 BP 729 EP 736 DI 10.1002/1522-2683(200102)22:4<729::AID-ELPS729>3.0.CO;2-O PG 8 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 410DL UT WOS:000167424700015 PM 11296928 ER PT J AU Song, JM Yeung, ES AF Song, JM Yeung, ES TI Optimization of DNA electrophoretic behavior in poly(vinyl pyrrolidone) sieving matrix for DNA sequencing SO ELECTROPHORESIS LA English DT Article DE poly(vinyl pyrrolidone); DNA sequencing ID CAPILLARY-ARRAY ELECTROPHORESIS; DYES; MOBILITY; SYSTEM; FLOW AB Poly(vinyl pyrrolidone) solution was used as a separation matrix in capillary electrophoresis for DNA sequencing. Four-label four-color detection was performed for base calling. Dye-labeled DNA showed large mobility shifts at normal conditions for DNA separation. Temporal correction of mobility shifts was achieved by normalizing with respect to pure peaks that are without spectral interference or temporal overlap at each color channel. To achieve even better performance, a DNA separation condition that does not require corrections for mobility shifts was found. Dichlororhodamine-labeled DNA fragments showed ideal electrophoretic behaviors according to DNA size in the presence of 10 M urea. The base-calling accuracy of dichlororhodamine-labeled M13mp18 and PGEM/U DNA were 99.3% for 333 bases and 99% for 315 bases, respectively. Base calling of unknown DNA samples obtained in the presence of 10 M urea showed 99.1% accuracy. C1 Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. NR 18 TC 31 Z9 32 U1 0 U2 2 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD FEB PY 2001 VL 22 IS 4 BP 748 EP 754 DI 10.1002/1522-2683(200102)22:4<748::AID-ELPS748>3.3.CO;2-B PG 7 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 410DL UT WOS:000167424700017 PM 11296930 ER PT J AU Bochkareva, E Belegu, V Korolev, S Bochkarev, A AF Bochkareva, E Belegu, V Korolev, S Bochkarev, A TI Structure of the major single-stranded DNA-binding domain of replication protein A suggests a dynamic mechanism for DNA binding SO EMBO JOURNAL LA English DT Article DE crystal structure; DNA binding; OB-fold; replication protein A; single-stranded DNA ID X-RAY-DIFFRACTION; NUCLEOTIDE EXCISION-REPAIR; CRYSTAL-STRUCTURE; SELENOMETHIONYL PROTEIN; FUNCTIONAL DOMAINS; A RPA; SUBUNIT; COMPLEX; REVEALS; SSB AB Although structures of single-stranded (ss)DNA-binding proteins (SSBs) have been reported with and without ssDNA, the mechanism of ssDNA binding in eukarya remains speculative. Here we report a 2.5 Angstrom structure of the ssDNA-binding domain of human replication protein A (RPA) (eukaryotic SSB), for which we previously reported a structure in complex with ssDNA, A comparison of free and bound forms of RPA revealed that ssDNA binding is associated with a major reorientation between, and significant conformational changes within, the structural modules-OB-folds-which comprise the DNA-binding domain. Two OB-folds, whose tandem orientation was stabilized by the presence of DNA, adopted multiple orientations in its absence. Within the OB-folds, extended loops implicated in DNA binding significantly changed conformation in the absence of DNA, Analysis of intermolecular contacts suggested the possibility that other RPA molecules and/or other proteins could compete with DNA for the same binding site. Using this mechanism, protein-protein interactions can regulate, and/or be regulated by DNA binding. Combined with available biochemical data, this structure also suggested a dynamic model for the DNA-binding mechanism. C1 Univ Oklahoma, Hlth Sci Ctr, Dept Biochem & Mol Biol, Oklahoma City, OK 73190 USA. Argonne Natl Lab, Struct Biol Ctr, Argonne, IL 60439 USA. RP Bochkarev, A (reprint author), Univ Oklahoma, Hlth Sci Ctr, Dept Biochem & Mol Biol, 975 NE 10th St,BRC-466, Oklahoma City, OK 73190 USA. FU NIGMS NIH HHS [R01 GM061192, GM61192-01] NR 39 TC 112 Z9 115 U1 1 U2 5 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0261-4189 J9 EMBO J JI Embo J. PD FEB 1 PY 2001 VL 20 IS 3 BP 612 EP 618 DI 10.1093/emboj/20.3.612 PG 7 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 400BH UT WOS:000166848400030 PM 11157767 ER PT J AU McCleskey, TM Foreman, TM Hallman, EE Burns, CJ Sauer, NN AF McCleskey, TM Foreman, TM Hallman, EE Burns, CJ Sauer, NN TI Approaching zero discharge in uranium reprocessing: Photochemical reduction of uranyl SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID SPECTROSCOPY; U(VI) AB We have studied the photochemical reduction of uranyl to generate UO2 without hydrogen reduction. Formate and oxalate were examined as potential reductants that only lead to CO2 production as a side product. Despite the similar nature of the two reductants, the mechanism for quenching the uranyl excited-state changes drastically and leads to dramatically different chemistry at low pH. Oxalate quenches by unimolecular electron transfer and formate quenches by fl-atom abstraction. Because of the change in mechanism, photochemical reduction of uranyl with formate works with high efficiency at low pH while photolysis in the presence of oxalate leads to the generation of CO acid no net uranyl reduction. Photochemical reduction of uranyl with formate at low pH leads to U(IV) in solution that can then be precipitated as UO2 by simply raising the pH with yields as high as 99.992%. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP McCleskey, TM (reprint author), Univ Calif Los Alamos Natl Lab, MS J514, Los Alamos, NM 87545 USA. RI McCleskey, Thomas/J-4772-2012; OI Mccleskey, Thomas/0000-0003-3750-3245 NR 30 TC 25 Z9 26 U1 1 U2 17 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 FEB 1 PY 2001 VL 35 IS 3 BP 547 EP 551 DI 10.1021/es001078i PG 5 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 397ZA UT WOS:000166727700028 PM 11351727 ER PT J AU Van Loy, MD Riley, WJ Daisey, JM Nazaroff, WW AF Van Loy, MD Riley, WJ Daisey, JM Nazaroff, WW TI Dynamic behavior of semivolatile organic compounds in indoor air. 2. Nicotine and phenanthrene with carpet and wallboard SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID ENVIRONMENTAL TOBACCO-SMOKE; EXPOSURE; CHAMBER; SORPTION; VAPOR; EMISSIONS; SURFACES; MODEL AB The surface interactions of nicotine and phenanthrene with carpet, painted wallboard, and stainless steel were investigated in a room-sized environmental test chamber. Adsorption kinetics were tested by flash evaporating a known mass of each compound into a sealed 20 m(3) chamber containing one or more of the tested sorbents. In each experiment, one or more emissions were performed after the gas-phase concentration had reached an apparent plateau. At the end of each experiment, the chamber was ventilated and resealed to monitor reemission of the compound from the sorbents. Kinetic sorption parameters were determined by fitting a mass-balance model to the experimental results. The sorption capacity of stainless steel was of similar magnitude for nicotine and phenanthrene. Sorption of nicotine on carpet and wallboard was much stronger, with equilibrium partitioning values 2-3 orders of magnitude higher. The sorption capacities of phenanthrene on carpet and wallboard were smaller, approximately 10-20% of the stainless steel values. The rates of uptake are of similar magnitude for all sorbate-sorbent pairs and are consistent with the limit imposed by gas-phase boundary/layer mass transport. The rates of desorption are much faster for phenanthrene than for nicotine. Model simulations predict average nicotine levels in a typical smoking residence that are consistent with published data. C1 Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Indoor Environm Dept, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Nazaroff, WW (reprint author), Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. RI Nazaroff, William/C-4106-2008; Riley, William/D-3345-2015 OI Nazaroff, William/0000-0001-5645-3357; Riley, William/0000-0002-4615-2304 FU NHLBI NIH HHS [R01-HL42490] NR 44 TC 47 Z9 47 U1 3 U2 17 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 FEB 1 PY 2001 VL 35 IS 3 BP 560 EP 567 DI 10.1021/es001372a PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 397ZA UT WOS:000166727700030 PM 11351729 ER PT J AU Doskey, PV Bialk, HM AF Doskey, PV Bialk, HM TI Automated sampler for the measurement of non-methane organic compounds SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID OXYGENATED HYDROCARBONS; EMISSIONS; SITE; AIR AB An automated sampler has been constructed for the unattended collection of whole-air samples in Summa passivated stainless steel canisters. The sampler consists of a Viton diaphragm pump; a differential-pressure flow controller; a 2-position, 3-port valve; a 10-port multiposition valve; and a digital Valve sequence programmer that controls the sequence and timing of the electrically actuated valves. All connecting tubing was constructed from Silcosteel tubing. Two configurations of the automated sampler and a passive collection system were evaluated by comparing the combined sampling precisions of the three systems with the analytic precision, derived from replicate analyses of an ambient air sample. The analytic precision was generally < +/-5%, with higher values observed for analytes with mixing ratios in the tens of pptv. However, analytic precision values for methanol and ethanol were poor, greater than +/-20%. Values for sampling precision were greater by about a factor of 2 than the analytic precision. The poor results for the light oxygenated hydrocarbons could be caused by sorption of the analytes in the preconcentration and sampling systems and difficulties in peak integration. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Doskey, PV (reprint author), Argonne Natl Lab, Div Environm Res, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 15 Z9 15 U1 1 U2 5 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 FEB 1 PY 2001 VL 35 IS 3 BP 591 EP 594 DI 10.1021/es001193t PG 4 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 397ZA UT WOS:000166727700034 PM 11351733 ER PT J AU Krucken, R Asztalos, SJ Clark, RM Deleplanque, MA Diamond, RM Fallon, P Lee, IY Macchiavelli, AO Schmid, GJ Stephens, FS Vetter, K Zhang, JY AF Krucken, R Asztalos, SJ Clark, RM Deleplanque, MA Diamond, RM Fallon, P Lee, IY Macchiavelli, AO Schmid, GJ Stephens, FS Vetter, K Zhang, JY TI Spectroscopy of Pd-112 using heavy-ion-induced fission SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID RICH PD ISOTOPES; NEUTRON; NUCLEI; DECAYS; STATES; BANDS AB High-spin states in Pd-112 were studied using prompt gamma -ray spectroscopy with Gammasphere following heavy-ion-induced fission in the reaction O-18 + Pb-208 at 91 MeV. A new 8(+) level at 2638 keV was discovered with transitions connecting it to the S rast band and the quasi-gamma band. The three, now established, closely spaced 8(+) states indicate a mixing between the ground-state band, s-band, and quasi-gamma band. Several high-spin structures with likely negative parity half been extended to higher spin and it is proposed that they are based on the nuh(11/2)((97/2)d(5/2)) and nuh(11/2)(s(1/2)d(3/2)) configurations. C1 Yale Univ, AW Wright Nucl Struct Lab, New Haven, CT 06520 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Tennessee, Knoxville, TN 37996 USA. RP Krucken, R (reprint author), Yale Univ, AW Wright Nucl Struct Lab, New Haven, CT 06520 USA. RI Kruecken, Reiner/A-1640-2013 OI Kruecken, Reiner/0000-0002-2755-8042 NR 15 TC 19 Z9 20 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD FEB PY 2001 VL 10 IS 2 BP 151 EP 155 DI 10.1007/s100500170127 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 429QC UT WOS:000168527600007 ER PT J AU Bruckel, T Hupfeld, D Strempfer, J Caliebe, W Mattenberger, K Stunault, A Bernhoeft, N McIntyre, GJ AF Bruckel, T Hupfeld, D Strempfer, J Caliebe, W Mattenberger, K Stunault, A Bernhoeft, N McIntyre, GJ TI Antiferromagnetic order and phase transitions in GdS as studied with X-ray resonance-exchange scattering SO EUROPEAN PHYSICAL JOURNAL B LA English DT Article ID MAGNETIC SCATTERING; POLARIZATION DEPENDENCE; DIFFRACTION; HOLMIUM; ERBIUM; WIDTHS; EUS AB We report on X-ray resonance exchange and neutron scattering of metallic GdS. At the L(II) and L(III) absorption edges of Gd, resonance enhancements of more than two orders of magnitude over the non-resonant magnetic scattering: are observed. Polarisation analysis proves that these enhancements are due to dipolar transitions from the 2p to the 5d states. The branching ratio between the L(II) and L(III) edges of 2.5 suggests a polarisation of the 5d electrons in the ground state. The antiferromagnetic order is of type II in the fcc lattice. Single crystal diffraction of hot neutrons suggests that the spin direction lies within the (111) planes with a value for the sublattice magnetisation of 6.51(3) mu (B). The critical exponent for the sublattice magnetisation has a value of beta = 0.38(2) in agrement with a pure Heisenberg model. Above TN, a sharp component persists ill the critical diffuse scattering. Lattice distortions give indications for two additional low-temperature phase transitions at about 49 K and 32 K. We argue that these transitions are not connected to spin reorientations and discuss the possible influence of fourth-order exchange interactions. C1 Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. ETH Honggerberg, Festkorperphys Lab, CH-8093 Zurich, Switzerland. European Synchrotron Radiat Facil, F-38043 Grenoble 9, France. CEA, DRFMC, F-38054 Grenoble, France. Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. RP Bruckel, T (reprint author), Forschungszentrum Julich, Inst Festkorperforsch, Postfach 1913, D-52425 Julich, Germany. EM T.Brueckel@fz-juelich.de RI Bruckel, Thomas/J-2968-2013 OI Bruckel, Thomas/0000-0003-1378-0416 NR 39 TC 18 Z9 18 U1 0 U2 4 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6028 J9 EUR PHYS J B JI Eur. Phys. J. B PD FEB PY 2001 VL 19 IS 4 BP 475 EP 490 DI 10.1007/s100510170293 PG 16 WC Physics, Condensed Matter SC Physics GA 421MY UT WOS:000168069200001 ER PT J AU Deliot, F Moreau, G Royon, C AF Deliot, F Moreau, G Royon, C TI Single superpartner production at Tevatron Run II SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID R-PARITY VIOLATION; TOP-QUARK PRODUCTION; FERMILAB-TEVATRON; HADRON COLLIDERS; LEPTON-NUMBER; SUSY SIGNALS; CERN LHC; SUPERSYMMETRY; COLLISIONS; SIGNATURES AB We study the single production of supersymmetric particles at Tevatron Run II which occur in the 2 --> 2 - body processes involving R-parity violating couplings of type lambda ' (ijk)L(i)Q(j)D(k)(c). T;Ve focus on the single gaugino production which receive contributions from the resonant slepton production. We first calculate the amplitudes of the single gaugino production. Then we perform analyses of the single gaugino production based on the three charged leptons and like sign dilepton signatures. These analyses allow to probe supersymmetric particles masses beyond the present experimental limits, and many of the X:jk coupling constants down to values smaller than the low-energy bounds. Finally, we show that the studies of the single gaugino production offer the opportunity to reconstruct the <()over tilde>(0)(1), <()over tilde>(+/-)(1), (v) over tilde (L) and (l) over tilde (+/-)(L) masses with a good accuracy in a model independent way. C1 CEA Saclay, DAPNIA, Serv Phys Particules, F-91191 Gif Sur Yvette, France. CEA Saclay, Serv Phys Theor, F-91191 Gif Sur Yvette, France. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Texas, Arlington, TX 76019 USA. RP CEA Saclay, DAPNIA, Serv Phys Particules, F-91191 Gif Sur Yvette, France. RI Deliot, Frederic/F-3321-2014 NR 56 TC 9 Z9 9 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6044 EI 1434-6052 J9 EUR PHYS J C JI Eur. Phys. J. C PD FEB PY 2001 VL 19 IS 1 BP 155 EP 181 DI 10.1007/s100520100568 PG 27 WC Physics, Particles & Fields SC Physics GA 421NA UT WOS:000168069400014 ER PT J AU Petrovic, C Movshovich, R Jaime, M Pagliuso, PG Hundley, MF Sarrao, JL Fisk, Z Thompson, JD AF Petrovic, C Movshovich, R Jaime, M Pagliuso, PG Hundley, MF Sarrao, JL Fisk, Z Thompson, JD TI A new heavy-fermion superconductor CeIrIn5: A relative of the cuprates? SO EUROPHYSICS LETTERS LA English DT Article ID CERHIN5; METALS; STATES; ORDER AB CeIrIn5 is a member of a new family of heavy-fermion compounds and has a Sommerfeld specific-heat coefficient of 720 mJ/molK(2). It exhibits a bulk, thermodynamic transition to a superconducting state at T-c = 0.40 K: below which the specific heat decreases as T-2 to a small residual T-linear value. Surprisingly, the electrical resistivity drops below instrumental resolution at a much higher temperature T-0 = 1.2 K. These behaviors are highly reproducible and field-dependent studies indicate that T-0 and T-c arise from the same underlying electronic structure. The layered crystal structure of CeIrIn5 suggests a possible analogy to the cuprates in which spin/charge pair correlations develop a ell above T-c. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RP Petrovic, C (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Petrovic, Cedomir/A-8789-2009; Pagliuso, Pascoal/C-9169-2012; Jaime, Marcelo/F-3791-2015 OI Petrovic, Cedomir/0000-0001-6063-1881; Jaime, Marcelo/0000-0001-5360-5220 NR 19 TC 414 Z9 416 U1 2 U2 46 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 FEB 1 PY 2001 VL 53 IS 3 BP 354 EP 359 DI 10.1209/epl/i2001-00161-8 PG 6 WC Physics, Multidisciplinary SC Physics GA 403RX UT WOS:000167057200012 ER PT J AU Ran, QT Wadhwa, R Bischof, O Venable, S Smith, JR Pereira-Smith, OM AF Ran, QT Wadhwa, R Bischof, O Venable, S Smith, JR Pereira-Smith, OM TI Characterization of a novel zinc finger gene with increased expression in nondividing normal human cells SO EXPERIMENTAL CELL RESEARCH LA English DT Article DE cell senescence; quiescence; transcriptional repression; nuclear matrix AB We report here the cloning and characterization of a novel KRAB zinc finger gene, ZFQR, which has eight tandemly repeated zinc fingers, a complete KRAB box at the N-terminal region, and a unique C-terminal sequence. It is expressed in a variety of human tissues, and mRNA levels are upregulated in nondividing senescent and quiescent human fibroblasts. Overexpression of the protein in quiescent cells stimulated with serum growth factors results in inhibition of entry into the cell cycle. The latter activity is lost when the N-terminal KRAB domain is deleted. The KRAB domain is also required for the transcriptional repression activity of ZFQR and in maintaining association of the protein with the nuclear matrix. The gene has been mapped to human chromosome 19q13.4. The association of ZFQR with the nuclear matrix, transcriptional repression activity, increased expression in senescent and quiescent cells, and the ability to inhibit quiescent cells stimulated with growth factors from entering the cell cycle suggests a role for ZFQR in the maintenance of the nondividing state of normal human cells. (C) 2001 Academic Press. C1 Baylor Coll Med, Roy M & Phyllis Gough Huffington Ctr Aging, Div Mol Virol, Dept Cell Biol, Houston, TX 77030 USA. Baylor Coll Med, Roy M & Phyllis Gough Huffington Ctr Aging, Div Mol Virol, Dept Med, Houston, TX 77030 USA. Mol Med Inc, Chugai Res Inst, Nihari Mura, Ibaraki 30041, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Cellular & Mol Biol, Berkeley, CA 94720 USA. RP Pereira-Smith, OM (reprint author), Baylor Coll Med, Huffington Ctr Aging, 1 Baylor Plaza, Houston, TX 77030 USA. FU NIA NIH HHS [R37AG05333, AG09909, P01AG13663] NR 20 TC 4 Z9 5 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0014-4827 J9 EXP CELL RES JI Exp. Cell Res. PD FEB 1 PY 2001 VL 263 IS 1 BP 156 EP 162 DI 10.1006/excr.2000.5068 PG 7 WC Oncology; Cell Biology SC Oncology; Cell Biology GA 397PF UT WOS:000166703500015 PM 11161714 ER PT J AU Kidd, SA Eskenazi, B Wyrobek, AJ AF Kidd, SA Eskenazi, B Wyrobek, AJ TI Effects of male age on semen quality and fertility: a review of the literature SO FERTILITY AND STERILITY LA English DT Review DE human male; age; semen; volume; concentration; motility; morphology; pregnancy; fertility; review ID INTRACYTOPLASMIC SPERM INJECTION; BROWN-NORWAY RAT; PATERNAL AGE; INTRAUTERINE INSEMINATION; INFERTILE COUPLES; HUSBANDS AGE; MEN; PARAMETERS; PREGNANCY; MORPHOLOGY AB Objective: To review the literature on the association between male age and semen quality (semen volume, concentration, motility, and morphology) and fertility status (pregnancy rate and time to pregnancy/subfecundity). Method(s): Review of English language-published research over the last 20 years from January 1, 1980, through December 31, 1999, using MEDLINE and Biosis databases. Studies with insufficient numbers of subjects, case reports, case series. or anecdotal data were excluded. Result(s): Among the methodologically stronger studies, decreases in semen volume of 3%-22%, decreases in sperm motility of 3%-37%, and decreases in percent normal sperm of 4%-18% were likely when comparing 30-year-old men to 50-year-old men. Most studies examining fertility status suggest a relationship between male age and fertility, but the results are most likely confounded by female partner age. Among studies that did control for female age, comparisons between men under 30 and men over 50 found relative decreases in pregnancy rates between 23% and 38%. A comparison of the various age categories showed that the increased risks for subfecundity ranged from 11% to 250%. Conclusion(s): The weight of the evidence suggests that increased male age is associated with a decline in semen volume, sperm motility, and sperm morphology but not with sperm concentration. (C) 2001 by American Society for Reproductive Medicine. C1 Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. RP Eskenazi, B (reprint author), 2150 Shattuck Ave,Suite 600, Berkeley, CA 94720 USA. FU NIEHS NIH HHS [P42ES04705] NR 66 TC 302 Z9 318 U1 1 U2 26 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0015-0282 J9 FERTIL STERIL JI Fertil. Steril. PD FEB PY 2001 VL 75 IS 2 BP 237 EP 248 DI 10.1016/S0015-0282(00)01679-4 PG 12 WC Obstetrics & Gynecology; Reproductive Biology SC Obstetrics & Gynecology; Reproductive Biology GA 400LB UT WOS:000166872100001 PM 11172821 ER PT J AU Stokes, DL Griffin, GD Vo-Dinh, T AF Stokes, DL Griffin, GD Vo-Dinh, T TI Detection of E-coli using a microfluidics-based antibody biochip detection system SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article ID MEMBRANE-FILTER METHOD; IN-GROUND BEEF; ESCHERICHIA-COLI; TOTAL COLIFORMS; RAPID DETECTION; DRINKING-WATER; MULTIPLEX PCR; MI-AGAR; O157-H7; ENUMERATION AB This work demonstrates the detection of E. coli using a 2-dimensional photosensor array biochip which is efficiently equipped with a microfluidics sample/reagent delivery system for on-chip monitoring of bioassays. The biochip features a 4 x 4 array of independently operating photodiodes that are integrated along with amplifiers, discriminators and logic circuitry on a single platform. The microfluidics system includes a single 0.4 mt reaction chamber which houses a sampling platform that selectively captures detection probes from a sample through the use of immobilized bioreceptors. The independently operating photodiodes allow simultaneous monitoring of multiple samples. In this study the sampling platform is a cellulosic membrane that is exposed to E. coli organisms and subsequently analyzed using a sandwich immunoassay involving a Cy5-labeled antibody probe. The combined effectiveness of the integrated circuit (IC) biochip and the immunoassay is evaluated for assays performed both by conventional laboratory means followed by detection with the IC biochip, and through the use of the mi crofluidics system for on-chip detection. Highlights of the studies show that the biochip has a linear dynamic range of three orders of magnitude observed for conventional assays, and can detect 20 E. cull organisms. Selective detection of E. Loll in a complex medium, milk diluent, is also reported for both off-chip and on-chip assays. C1 Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. RP Vo-Dinh, T (reprint author), Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. EM vodinht@ornl.gov NR 32 TC 48 Z9 52 U1 1 U2 12 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD FEB PY 2001 VL 369 IS 3-4 BP 295 EP 301 DI 10.1007/s002160000660 PG 7 WC Chemistry, Analytical SC Chemistry GA 407LP UT WOS:000167273300015 PM 11293707 ER PT J AU Angel, SM Stratis, DN Eland, KL Lai, TS Berg, MA Gold, DM AF Angel, SM Stratis, DN Eland, KL Lai, TS Berg, MA Gold, DM TI LIBS using dual- and ultra-short laser pulses SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article ID INDUCED BREAKDOWN SPECTROSCOPY; INDUCED PLASMA SPECTROSCOPY; X-RAYS; ABLATION; PROBE; METALS; MICROSCOPY; EMISSION; LIQUIDS; SAMPLES AB Pre-ablation dual-pulse LIBS enhancement data for copper, brass and steel using ns laser excitation are reported. Although large enhancements are observed for all samples, the magnitude of the enhancement is matrix dependent. Whereas all of the dual-pulse studies used ns laser excitation we see interesting effects when using ps and fs laser excitation for single-pulse LIBS. LIBS spectra of copper using 1.3 ps and 140 fs laser pulses show much lower background signals compared to ns pulse excitation. Also. the atomic emission decays much more rapidly with time. Because of relatively low backgrounds when using ps and fs pulses, non-gated detection of LIBS is shown to be very effective. The plasma dissipates quickly enough using ps and fs laser pulses, that high pulse rates, up to 1000 Hz, are effective for increasing the LIBS signal, for a given measurement time. Finally, a simple near-collinear dual-pulse fiber-optic LIBS probe is shown to be useful for enhanced LIBS measurements. C1 Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. RP Angel, SM (reprint author), Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. OI Angel, Stanley/0000-0002-0328-0568 NR 39 TC 86 Z9 88 U1 3 U2 19 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD FEB PY 2001 VL 369 IS 3-4 BP 320 EP 327 DI 10.1007/s002160000656 PG 8 WC Chemistry, Analytical SC Chemistry GA 407LP UT WOS:000167273300019 PM 11293711 ER PT J AU Moore, DS AF Moore, DS TI Determination of energetic materials in soil using multivariate analysis of Raman spectra SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article ID PRINCIPAL COMPONENT ANALYSIS; CHROMATOGRAPHY AB Contamination of soils by energetic materials (EMs) is an important issue in many locations (such as test mounds, ordnance depots. and manufacturing sites). Raman spectroscopy can be useful as a screening technique at the percent level (by mass) if interference from soil fluorescence can be overcome. Multivariate analysis is shown capable of both extracting the Raman signatures of EMs from spectra obscured by large fluorescence backgrounds caused by soil components, and generating calibration curves for the EMs at the percent level. C1 Univ Calif Los Alamos Natl Lab, High Explos Sci & Technol Grp, Los Alamos, NM 87545 USA. RP Moore, DS (reprint author), Univ Calif Los Alamos Natl Lab, High Explos Sci & Technol Grp, MS-C920, Los Alamos, NM 87545 USA. RI Moore, David/C-8692-2013 NR 10 TC 6 Z9 6 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD FEB PY 2001 VL 369 IS 3-4 BP 393 EP 396 DI 10.1007/s002160000625 PG 4 WC Chemistry, Analytical SC Chemistry GA 407LP UT WOS:000167273300029 PM 11293721 ER PT J AU Jhang, HG Kessel, CE Pomphrey, N Kim, JY Jardin, SC Lee, GS AF Jhang, HG Kessel, CE Pomphrey, N Kim, JY Jardin, SC Lee, GS TI Simulation studies of plasma shape identification and control in Korea Superconducting Tokamak Advanced Research SO FUSION ENGINEERING AND DESIGN LA English DT Article DE plasma; tokamak; magnetic flux ID POSITION CONTROL; PARAMETERS; EXPANSION; DESIGN; ITER AB Simulation studies of plasma shape identification and shape control for the proposed Korea superconducting tokamak advanced research (KSTAR) are described. It is shown that the total number of magnetic measurements can be effectively reduced by considering the patterns of magnetic flux and fields? generated by plasma, along a prescribed measurement contour. The effect of eddy currents on shape identification is investigated in dynamic simulations. The isoflux control scheme and a standard PID control law are adopted for the development of a model shape control system. It is shown that appropriate weighting factors of poloidal field coils, incorporating the efficacy of each coil to a shape control point, can significantly reduce the total feedback power required for a shape control action. Finally, a share control simulation using calculated flux errors, which correspond to a more realistic experimental situation, is presented. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Korea Basic Sci Inst, Yusung Ku, Taejon, South Korea. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Jhang, HG (reprint author), Korea Basic Sci Inst, Yusung Ku, 52 Yeoeun Dong, Taejon, South Korea. RI Jardin, Stephen/E-9392-2010; pomphrey, neil/G-4405-2010 NR 17 TC 18 Z9 19 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 FEB PY 2001 VL 54 IS 1 BP 117 EP 134 DI 10.1016/S0920-3796(00)00431-2 PG 18 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 395NV UT WOS:000166587200011 ER PT J AU Abdou, MA Ying, A Morley, N Gulec, K Smolentsev, S Kotschenreuther, M Malang, S Zinkle, S Rognlien, T Fogarty, P Nelson, B Nygren, R McCarthy, K Youssef, MZ Ghoniem, N Sze, D Wong, C Sawan, M Khater, H Woolley, R Mattas, R Moir, R Sharafat, S Brooks, J Hassanein, A Petti, D Tillack, M Ulrickson, M Uchimoto, T AF Abdou, MA Ying, A Morley, N Gulec, K Smolentsev, S Kotschenreuther, M Malang, S Zinkle, S Rognlien, T Fogarty, P Nelson, B Nygren, R McCarthy, K Youssef, MZ Ghoniem, N Sze, D Wong, C Sawan, M Khater, H Woolley, R Mattas, R Moir, R Sharafat, S Brooks, J Hassanein, A Petti, D Tillack, M Ulrickson, M Uchimoto, T CA APEX Team TI On the exploration of innovative concepts for fusion chamber technology SO FUSION ENGINEERING AND DESIGN LA English DT Article DE chamber technology; first wall; blanket; liquid walls; free surface; refractory alloys; two-phase flow; plasma-material interaction; MHD effects ID PLASMA; SHEAR AB This study, called APEX. is exploring novel concepts for fusion chamber technology that can substantially improve the attractiveness of fusion energy systems. The emphasis of the study is on fundamental understanding and advancing the underlying engineering sciences, integration of the physics and engineering requirements, and enhancing innovation for the chamber technology components surrounding the plasma. The chamber technology goals in APEX include: (1) high power density capability with neutron wall load > 10 MW/m(2) and surface heat flux > 2 MW/m(2), (2) high power conversion efficiency (> 40%), (3) high availability, and (4) simple technological and material constraints. Two classes of innovative concepts have emerged that offer great promise and deserve further research and development. The first class seeks to eliminate the solid "bare" first wall by Bowing liquids facing the plasma. This liquid wall idea evolved during the APEX study into a number of concepts based on: (a) using liquid metals (Li or Sn-Li) or a molten salt (Flibe) as the working liquid, (b) utilizing electromagnetic, inertial and/or other types of forces to restrain the liquid against a backing wall and control the hydrodynamic flow configurations, and (c) employing a thin (similar to 2 cm) or thick (similar to 40 cm) liquid layer to remove the surface heat Bur and attenuate the neutrons. These liquid wall concepts have some common features but also have widely different issues and merits. Some of the attractive features of liquid walls include the potential for: (1) high power density capability; (2) higher plasma beta and stable physics regimes if liquid metals are used; (3) increased disruption survivability; (4) reduced volume of radioactive waste; (5) reduced radiation damage in structural materials; and (6) higher availability. Analyses show that not all of these potential advantages may be realized simultaneously in a single concept. However, the realization of only a subset of these advantages will result in remarkable progress toward attractive fusion energy systems. Of the many scientific and engineering issues for liquid walls, the most important are: (I) plasma-liquid interactions including both plasma-liquid surface and liquid wall-bulk plasma interactions; (2) hydrodynamic flow configuration control in complex geometries including penetrations; and (3) heat transfer at free surface and temperature control. The second class of concepts focuses on ideas for extending the capabilities, particularly the power density and operating temperature limits, of solid first walls. The most promising idea, called EVOLVE, is based on the use of a high-temperature refractory alloy (e.g. W-5% Re) with an innovative cooling scheme based on the use of the heat of vaporization of lithium. Calculations show that an evaporative system with Li at similar to 1 200 degreesC can remove the goal heat loads and result in a high power conversion efficiency. The vapor operating pressure is low, resulting in a very low operating stress in the structure. In addition, the lithium flow rate is about a factor of ten lower than that required for traditional self-cooled first wall/blanket concepts. Therefore, insulator coatings are not required. Key issues for EVOLVE include: (1) two-phase heat transfer and transport including MHD effects; (2) feasibility of fabricating entire blanket segments of W alloys; and (3) the effect of neutron irradiation on W. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Angeles, Dept Aerosp & Mech Engn, Los Angeles, CA 90095 USA. Univ Texas, Austin, TX 78712 USA. Forschungszentrum Karlsruhe, D-76021 Karlsruhe, Germany. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. Argonne Natl Lab, Argonne, IL 60439 USA. Gen Atom Co, San Diego, CA USA. Univ Wisconsin, Madison, WI USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Tokyo, Tokyo, Japan. RP Abdou, MA (reprint author), Univ Calif Los Angeles, Dept Aerosp & Mech Engn, 44-114 Engn IV,420 Westwood Plaza, Los Angeles, CA 90095 USA. RI Ghoniem, Nasr/A-9799-2008; OI Zinkle, Steven/0000-0003-2890-6915 NR 40 TC 200 Z9 204 U1 2 U2 29 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 FEB PY 2001 VL 54 IS 2 BP 181 EP 247 DI 10.1016/S0920-3796(00)00433-6 PG 67 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 395NW UT WOS:000166587300003 ER PT J AU Munsat, T AF Munsat, T TI High-temperature carbon-irradiation issues for the Sombrero ICF reactor SO FUSION ENGINEERING AND DESIGN LA English DT Article DE carbon-fiber-composite; graphites; Sombero ICF reactor; neutron irradiation ID NEUTRON-IRRADIATION; THERMAL-CONDUCTIVITY AB In order to assess the feasibility of carbon materials for the first-wall of the Sombrero KrF laser-driven ICF fusion reactor [W.R. Meier et al., OSIRIS and SOMBRERO Inertial Fusion Power Plant Designs, W.J. Schafer Associates Report, WSJA-92-01, DOE/ER/54100-1 (1992); W.R. Meier, et al., Fus. Eng. Des. 25 (1994) 145-157; I.N. Sviatoslavsky, et al., Fus.Tech. 21 (1992) 1470-1474], published experimental results relating to mechanical and thermal properties of graphites and carbon-fiber-composites (CFC's) under neutron irradiation and high heat loads are reviewed. Results are compared to published design requirements for the Sombrero ICF reactor, with particular attention to three separate issues of concern: (1) Erosion rates of the first wall are highly sensitive to the thermal conductivity value, which is itself environment-sensitive (radiation and high temperature). Erosion rates at the first wall are calculated here using a high-temperature post-irradiation conductivity value of 50 W/m K, with complete erosion of the first wall layer predicted within 1.25 full-power years (FPY), illustrating the sensitivity of erosion rates to thermal conductivity assumptions; (2) Radiation-induced swelling in 2-D and 'pseudo 3-D' CFC's is consistently similar to 20% under high-temperature neutron damage of 5 dpa (0.33 FPY). This level of swelling would pose technical challenges to the engineering of the target chamber modules; (3) Total tritium retention is predicted to be similar to 0.5-5 kg in the Sombrero chamber within 0.67 FPY, which may call into question safety-status assumptions of the CFC-based chamber design,. These results indicate the urgency of high-temperature neutron-irradiation tests of fully symmetric 3-D CFC's in order to support the plausibility of a carbon first-wall IFE chamber such as proposed for Sombrero. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Munsat, T (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 27 TC 2 Z9 2 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 FEB PY 2001 VL 54 IS 2 BP 249 EP 261 DI 10.1016/S0920-3796(00)00467-1 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 395NW UT WOS:000166587300004 ER PT J AU Neumeyer, C Heitzenroeder, P Spitzer, J Chrzanowski, J Brooks, A Bialek, J Fan, HM Barnes, G Viola, M Nelson, B Goranson, P Wilson, R Fredd, E Dudek, L Parsells, R Kalish, M Blanchard, W Kaita, R Kugel, H McCormack, B Ramakrishnan, S Hatcher, R Oliaro, G Perry, E Egebo, T Von Halle, A Williams, M Ono, M AF Neumeyer, C Heitzenroeder, P Spitzer, J Chrzanowski, J Brooks, A Bialek, J Fan, HM Barnes, G Viola, M Nelson, B Goranson, P Wilson, R Fredd, E Dudek, L Parsells, R Kalish, M Blanchard, W Kaita, R Kugel, H McCormack, B Ramakrishnan, S Hatcher, R Oliaro, G Perry, E Egebo, T Von Halle, A Williams, M Ono, M TI Engineering design of the National Spherical Torus Experiment SO FUSION ENGINEERING AND DESIGN LA English DT Article DE engineering design; the National Spherical Torus Experiment; proof-of-principle spherical torus ID CURRENTS; TOKAMAK AB NSTX is a proof-of-principle experiment aimed at exploring the physics of the 'spherical torus' (ST) configuration. which is predicted to exhibit more efficient magnetic confinement than conventional large aspect ratio tokamaks. among other advantages. The low aspect ratio (R/a, typically 1.2-2 in ST designs compared to 4-5 in conventional tokamaks) decreases the available cross sectional area through the center of the torus for toroidal and poloidal field coil conductors, vacuum vessel wall, plasma facing components. etc.. thus increasing the need to deploy all components within the so-called 'center stack' in the most efficient manner possible. Several unique design features have been developed for the NSTX center stack, and careful engineering of this region of the machine, utilizing materials up to their engineering allowables. has been key to meeting the desired objectives. The design and construction of the machine has been accomplished in a rapid and cost effective manner thanks to the availability of extensive facilities, a strong experience base from the TFTR era. and good cooperation between institutions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Princeton Univ, Dept Energy, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Columbia Univ, New York, NY USA. RP Neumeyer, C (reprint author), Princeton Univ, Dept Energy, Princeton Plasma Phys Lab, JMS Forrestal CMPS REC 3-PPL, Princeton, NJ 08544 USA. NR 29 TC 21 Z9 22 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 FEB PY 2001 VL 54 IS 2 BP 275 EP 319 DI 10.1016/S0920-3796(00)00469-5 PG 45 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 395NW UT WOS:000166587300006 ER PT J AU Roix, JJ Hagge-Greenberg, A Bissonnette, DM Rodick, S Russell, LB O'Brien, TP AF Roix, JJ Hagge-Greenberg, A Bissonnette, DM Rodick, S Russell, LB O'Brien, TP TI Molecular and functional mapping of the piebald deletion complex on mouse chromosome 14 SO GENETICS LA English DT Article ID N-NITROSOUREA MUTAGENESIS; EMBRYONIC STEM-CELLS; EXTRAEMBRYONIC ECTODERM; INDUCED MUTATIONS; LOCUS; MICE; GENE; MAP; REQUIREMENT; RADIATION AB The piebald deletion complex is a set of overlapping chromosomal deficiencies surrounding the endothelin receptor B locus collected during the Oak Ridge specific-locus-test mutagenesis screen. These chromosomal deletions represent an important resource for genetic studies to dissect the functional content of a genomic region, and several developmental defects hale been associated with mice homozygous for distinct piebald deletion alleles. We have used molecular markers to order the breakpoints for 20 deletion alleles that span a 15.7-18-cM region of distal mouse chromosome 14. Large deletions covering as much as 11 chi have been identified that will be useful for regionally directed mutagenesis screens to reveal recessive mutations that disrupt development. Deletions identified as haring breakpoints positioned within previously described critical regions have been used in complementation studies to further define the functional intervals associated with the developmental defects. This has focused our efforts to isolate genes required for newborn respiration and survival skeletal patterning and morphogenesis, and central nervous system development. C1 Jackson Lab, Bar Harbor, ME 04609 USA. Oak Ridge Natl Lab, Div Biol, Oak Ridge, TN 37831 USA. RP O'Brien, TP (reprint author), Jackson Lab, 600 Main St, Bar Harbor, ME 04609 USA. FU NCI NIH HHS [CA34196]; NICHD NIH HHS [HD36434] NR 36 TC 20 Z9 21 U1 0 U2 0 PU GENETICS PI BALTIMORE PA 428 EAST PRESTON ST, BALTIMORE, MD 21202 USA SN 0016-6731 J9 GENETICS JI Genetics PD FEB PY 2001 VL 157 IS 2 BP 803 EP 815 PG 13 WC Genetics & Heredity SC Genetics & Heredity GA 399KL UT WOS:000166810200032 PM 11156998 ER PT J AU Lea, AS Amonette, JE Baer, DR Liang, Y Colton, NG AF Lea, AS Amonette, JE Baer, DR Liang, Y Colton, NG TI Microscopic effects of carbonate, manganese, and strontium ions on calcite dissolution SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID SCANNING FORCE MICROSCOPY; WATER INTERFACE; CRYSTAL-GROWTH; CO2-WATER SYSTEMS; AQUEOUS-SOLUTION; SURFACE; KINETICS; INHIBITION; COPRECIPITATION; PRECIPITATION AB Aqueous dissolution of the (10 (1) over bar4) surface of calcite was observed at pH near 9 by using an atomic Force microscope equipped with a fluid cell. The influences of carbonate (CO32-), strontium (Sr2+), and manganese (Mn2+) ion concentrations on the rates of step motion were measured. Carbonate ions were shown to have a step-specific effect on calcite dissolution. At low levels (<1 M) of CO32-, the retreat rate of the more structurally open [(4) over bar 41](+) steps was faster than the retreat rate of the structurally confined [(4) over bar 41]_ steps, leading to anisotropic dissolution. Increasing the CO32- level to as high as 900 muM decreased the rate of retreat of both steps. but the [(4) over bar 41](+) step was slowed to a much greater extent changing the degree of dissolution anisotropy. This decrease in step velocity at high CO32- levels was attributed to a corresponding increase in the back reaction (i.e., precipitation) as the solution approached saturation with respect to calcite. Strontium cations were also shown to have a step-specific effect on calcite dissolution similar to that of CO32-. Manganese cations, on the other hand, slowed the rate of retreat of the [(4) over bar 41] step to a greater extent than Sr2+. The influence of impurity metal sorption on dissolution is examined in terms of sorption at kinks and the dissolution behavior is explained in terms of a terrace-ledge-kink site-blocking model. Evidence is given to support the hypothesis that ion-pairs formed in solution are the primary growth units for calcite. Copyright (C) 2000 Elsevier Science Ltd. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, Environm Mol Sci Lab, Box 999,MS K8-93, Richland, WA 99352 USA. EM Scott.Lea@pnl.gov RI Baer, Donald/J-6191-2013; OI Baer, Donald/0000-0003-0875-5961; Lea, Alan/0000-0002-4232-1553 NR 50 TC 84 Z9 84 U1 1 U2 33 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 EI 1872-9533 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD FEB PY 2001 VL 65 IS 3 BP 369 EP 379 DI 10.1016/S0016-7037(00)00531-7 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 399AP UT WOS:000166788900002 ER PT J AU Schroeder, PA Melear, ND Bierman, P Kashgarian, M Caffee, MW AF Schroeder, PA Melear, ND Bierman, P Kashgarian, M Caffee, MW TI Apparent gibbsite growth ages for regolith in the Georgia Piedmont SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID COSMOGENIC NUCLIDES; EROSION RATES; BE-10; EVOLUTION; CARBONATE; EXPOSURE; CLIMATE; PROFILE; MODEL; C-14 AB Carbon bound in gibbsite, collected from a residual weathering profile developed on a Paleozoic granite in the Georgia Piedmont, was examined for its C-14 content and found to be geologically young. The study site, located at the Panola Mountain Research Watershed, has developed a granite-saprolite-soil regolith in which C-14-gibbsite model ages deep within the profile (C-horizon) average about 8000 years. Near the surface (A- and B-horizon) C-14-gibbsite model ages range from 2100 to 4200 years. Quartz has acquired Al-26 and Be-10 inventories suggesting a near-surface residence time of at least 90,000 years. This age disparity supports the notion that secondary minerals undergo significant recrystallization as weathering fronts propagate into the landscape. Combining the results of C-14, Al-26, and Be-10 analyses offers the potential to assess differential rates of chemical weathering and continental denudation to understand better the links between rates of silicate rock weathering, climate, and soil residence times. Copyright (C) 2001 Elsevier Science Ltd. C1 Univ Georgia, Dept Geol, Athens, GA 30602 USA. Univ Vermont, Dept Geol, Burlington, VT 05405 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Schroeder, PA (reprint author), Univ Georgia, Dept Geol, 210 Field St, Athens, GA 30602 USA. RI Kashgarian, Michaele/E-1665-2011; Caffee, Marc/K-7025-2015 OI Kashgarian, Michaele/0000-0001-7824-8418; Caffee, Marc/0000-0002-6846-8967 NR 31 TC 13 Z9 14 U1 0 U2 3 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 FEB PY 2001 VL 65 IS 3 BP 381 EP 386 DI 10.1016/S0016-7037(00)00541-X PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 399AP UT WOS:000166788900003 ER PT J AU Zehfuss, PH Bierman, PR Gillespie, AR Burke, RM Caffee, MW AF Zehfuss, PH Bierman, PR Gillespie, AR Burke, RM Caffee, MW TI Slip rates on the Fish Springs fault, Owens Valley, California, deduced from cosmogenic Be-10 and Al-26 and soil development on fan surfaces SO GEOLOGICAL SOCIETY OF AMERICA BULLETIN LA English DT Article DE fans; faulting; isotopes; Owens Valley; soils ID SIERRA-NEVADA; EXPOSURE; DEPOSITION; HISTORY; ROCKS; LAKE; PINE; AGES AB Long-term deformation along the Fish Springs fault in Owens Valley, California, is recorded by offset landforms, including a previously dated cinder cone (Ar-39/Ar-40, 314 +/- 36 ka, 2 sigma), several debris-flow fans and levees deposited by Birth Creek, stream channels, and lava flows of nearby Crater Mountain. The Be-10 and Al-26 model exposure ages (n = 68) delimit fan ages and suggest that deposition stopped after ca, 136, 15, 13, and 8 ka. One fan remains active and has undergone deposition throughout the Holocene. Soil development on three fans, where boulders were sampled for Be-10 and Al-26 analysis, also indicates distinct ages. Together, soil development and cosmogenic isotope data suggest that fan deposits correlate with the Tahoe and late Tioga glaciations. Soil profile development index values from Fish Springs are low compared with those determined elsewhere, suggesting relatively slow rates of soil formation for fan surfaces at Fish Springs and/or modification of soil profiles by surface processes during or following soil formation. Age estimates and measured offsets of the Fans are consistent with a long-term vertical slip rate of 0.24 +/- 0.04 m k.y.(-l) for the Fish Springs fault over the past 300 k.y. C1 Humboldt State Univ, Dept Geol, Arcata, CA 95521 USA. Univ Vermont, Dept Geol, Burlington, VT 05405 USA. Univ Washington, Dept Geol Sci, Seattle, WA 98195 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. RP Zehfuss, PH (reprint author), Univ Washington, Dept Geol Sci, Seattle, WA 98195 USA. RI Caffee, Marc/K-7025-2015 OI Caffee, Marc/0000-0002-6846-8967 NR 40 TC 50 Z9 50 U1 3 U2 11 PU ASSOC ENGINEERING GEOLOGISTS GEOLOGICAL SOCIETY AMER PI COLLEGE STN PA TEXAS A & M UNIV, DEPT GEOLOGY & GEOPHYSICS, COLLEGE STN, TX 77843-3115 USA SN 0016-7606 J9 GEOL SOC AM BULL JI Geol. Soc. Am. Bull. PD FEB PY 2001 VL 113 IS 2 BP 241 EP 255 DI 10.1130/0016-7606(2001)113<0241:SROTFS>2.0.CO;2 PG 15 WC Geosciences, Multidisciplinary SC Geology GA 398UX UT WOS:000166775800005 ER PT J AU Bekkering, FC Stalgis, C McHutchison, JG Brouwer, JT Perelson, AS AF Bekkering, FC Stalgis, C McHutchison, JG Brouwer, JT Perelson, AS TI Estimation of early hepatitis C viral clearance in patients receiving daily interferon and ribavirin therapy using a mathematical model SO HEPATOLOGY LA English DT Article ID SERUM HCV RNA; ALPHA THERAPY; VIRUS-RNA; IN-VIVO; COMBINATION; ALFA; PREDICTION; INFECTION; DYNAMICS AB Patients with hepatitis C virus (HCV) genotype 1 infection are resistant to standard interferon (IFN) therapy. We used a mathematical model to estimate the duration of daily therapy necessary to maximize the number of patients achieving viral negativity before 12 weeks of therapy. Patients from a study to determine HCV RNA reduction over 4 weeks using 3 million units (MU), 5 MU, or 10 MU of IFN alfa daily plus Ribavirin were compared with a group receiving IFN alfa 3 MU three times a week. By extending the linear regression and prediction interval lines, the estimated time to negativity was greater than 12 weeks for the standard IFN group, 42 to greater than 84 days for the 3 MU IFN daily plus Ribavirin, 39 to 60 days for 5 MU IFN daily plus Ribavirin and 25 to 45 days for the 10 MU IFN daily and Ribavirin group, respectively. Thus, the use of a predictive model based on log transformation and linear regression of the early HCV RNA response suggests daily doses of 5 or 10 million units of IFN plus Ribavirin will be theoretically necessary for longer than 4 weeks to maximize the number of patients who clear virus by 12 weeks of therapy. This model may be useful in predicting response in groups of patients receiving other therapies. C1 Scripps Clin & Res Fdn, Div Gastroenterol Hepatol 203N, La Jolla, CA 92037 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Univ Rotterdam Hosp, Dept Hepatogastroenterol, Rotterdam, Netherlands. Schering Plough, Kenilworth, NJ USA. RP McHutchison, JG (reprint author), Scripps Clin & Res Fdn, Div Gastroenterol Hepatol 203N, 10666 N Torrey Pines Rd, La Jolla, CA 92037 USA. FU NCRR NIH HHS [RR06555] NR 23 TC 60 Z9 61 U1 1 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 FEB PY 2001 VL 33 IS 2 BP 419 EP 423 DI 10.1053/jhep.2001.21552 PG 5 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 397QF UT WOS:000166705800013 PM 11172344 ER PT J AU Chow, WW Amano, H AF Chow, WW Amano, H TI Analysis of lateral-mode behavior in broad-area InGaN quantum-well lasers SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE laser modes; laser resonators; nitride compounds; optical self-focusing; piezoelectric effect; quantum-well lasers; semiconductor lasers; semiconductor device modeling ID UNSTABLE-RESONATOR; SEMICONDUCTOR-LASERS; MICROSCOPIC THEORY AB A wave-optical model that is coupled to a microscopic gain theory is used to investigate lateral mode behavior in group-iii nitride quantum-well lasers, Beam filamentation due to self-focusing in the gain medium is found to limit fundamental-mode output to narrow stripe lasers or to operation close to lasing threshold, Differences between nitride and conventional near-infrared semiconductor lasers arise because of band structure differences, in particular, the presence of a strong quantum-confined Stark effect in the former. Increasing mirror reflectivities in plane-plane resonators to reduce lasing threshold current tends to exacerbate the filamentation problem. On the other hand, a negative-branch unstable resonator is found to mitigate filament effects, enabling fundamental-mode operation far above threshold in broad-area lasers. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Meijo Univ, Dept Elect & Elect Engn, Tempaku Ku, Nagoya, Aichi 468, Japan. RP Chow, WW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 21 TC 24 Z9 24 U1 0 U2 2 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 FEB PY 2001 VL 37 IS 2 BP 265 EP 273 DI 10.1109/3.903077 PG 9 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 404YC UT WOS:000167129200013 ER PT J AU Stroud, PD AF Stroud, PD TI Kalman-extended genetic algorithm for search in nonstationary environments with noisy fitness evaluations SO IEEE TRANSACTIONS ON EVOLUTIONARY COMPUTATION LA English DT Article DE adaptive control; genetic algorithm; Kalman filter; network optimization ID SIMULATION; FILTERS; TREES AB In basic genetic algorithm (GA) applications, the fitness of a solution takes a value that is certain and unchanging, There are two classes of problem for which this formulation is insufficient. The first consists of ongoing searches for better solutions in a nonstationary environment in which the expected fitness of a solution changes with time in unpredictable ways. The second class consists of applications in which fitness evaluations are corrupted by noise. For problems belonging to either or both of these classes, the estimated fitness of a solution will have an associated uncertainty. Both the uncertainty due to environmental changes (process noise) and the uncertainty due to noisy evaluations (observation noise) can be reduced, at least temporarily, by re-evaluating existing solutions, The Kalman formulation provides a well-developed formal mechanism for treating uncertainty within the GA framework. It provides the mechanics for determining the estimated fitness and uncertainty when a new solution is generated and evaluated for the first time. It also provides the mechanics for updating the estimated fitness and uncertainty after an existing solution is re-evaluated and for increasing the uncertainty with the passage of time. A Kalman-extended genetic algorithm (KGA) is developed to determine when to generate a new individual, when to re-evaluate an existing individual, and which one to re-evaluate. This KGA is applied to the problem of maintaining a network configuration with minimized message loss in which the nodes are mobile and the transmission over a link is stochastic. As the nodes move, the optimal network changes, but information contained within the population of solutions allows efficient discovery of better-adapted solutions. The ability of the. KGA to continually find near-optimal solutions is demonstrated at several levels of process and observation noise. The sensitivity of the KGA performance to several control parameters is explored. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Stroud, PD (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 35 TC 40 Z9 43 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 1089-778X J9 IEEE T EVOLUT COMPUT JI IEEE Trans. Evol. Comput. PD FEB PY 2001 VL 5 IS 1 BP 66 EP 77 DI 10.1109/4235.910466 PG 12 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA 409EJ UT WOS:000167371300007 ER PT J AU Xu, XX Schein, J Qi, NS Prasad, RR Krishnan, M Fumihiko, T Tantawi, SG AF Xu, XX Schein, J Qi, NS Prasad, RR Krishnan, M Fumihiko, T Tantawi, SG TI The development of a diamond switch for RF pulse compression systems SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE diamond switch; microwave amplifier; RF compression; RF switch ID POWER AB The use of a diamond RF switch for super-highpower microwave/millimeter wave generation has been evaluated. An X-band chemical vapor deposition (CVD) diamond window package was theoretically analyzed, designed, and built. Thirty-eight percent of an injected microwave signal with a frequency of 11.424 GHz was reflected from a 100-mum thick, 22-mm-dianleter CVD diamond window when activated by a 160-mJ, 266-nm Nd:YAG laser The details of the CVD diamond window design and experimental results are presented, The results have high application potential for building super-high-power microwave systems. C1 Alameda Appl Sci Corp, San Leandro, CA 94577 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Xu, XX (reprint author), Alameda Appl Sci Corp, San Leandro, CA 94577 USA. NR 12 TC 2 Z9 2 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD FEB PY 2001 VL 29 IS 1 BP 85 EP 92 DI 10.1109/27.912946 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 416DT UT WOS:000167765500013 ER PT J AU Degnan, JH Taccetti, JM Cavazos, T Clark, D Coffey, SK Faehl, RJ Frese, MH Fulton, D Gueits, JC Gale, D Hussey, TW Intrator, TP Kirpatrick, RC Kiuttu, GH Lehr, FM Letterio, JD Lindemuth, I McCullough, WF Moses, R Peterkin, RE Reinovsky, RE Roderick, NF Ruden, EL Shlachter, JS Schoenberg, KF Siemon, RE Sommars, W Turchi, PJ Wurden, GA Wysocki, F AF Degnan, JH Taccetti, JM Cavazos, T Clark, D Coffey, SK Faehl, RJ Frese, MH Fulton, D Gueits, JC Gale, D Hussey, TW Intrator, TP Kirpatrick, RC Kiuttu, GH Lehr, FM Letterio, JD Lindemuth, I McCullough, WF Moses, R Peterkin, RE Reinovsky, RE Roderick, NF Ruden, EL Shlachter, JS Schoenberg, KF Siemon, RE Sommars, W Turchi, PJ Wurden, GA Wysocki, F TI Implosion of solid liner for compression of field reversed configuration SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE capacitor bank; Field reversed configuration; FRC; implosion; magnetized target fusion; megamp; MTF; radiography; solid liner ID ELECTROMAGNETIC IMPLOSION; FUSION AB The design and first successful demonstration of an imploding solid liner with height to diameter ratio, radial convergence, and uniformity suitable for compressing a field reversed configuration is discussed. Radiographs indicated a very symmetric implosion with no instability growth, with similar to 13 x radial compression of thp inner liner surface prior to impacting a central measurement unit. The implosion kinetic energy was 1.5 megajoules, 34% of the capacitor stored energy of 4.4 megajoules, C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Maxwell Technol Inc, Albuquerque, NM 87106 USA. NumerEx, Albuquerque, NM 87106 USA. Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. RP Degnan, JH (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 25 TC 26 Z9 26 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD FEB PY 2001 VL 29 IS 1 BP 93 EP 98 DI 10.1109/27.912947 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 416DT UT WOS:000167765500014 ER PT J AU Jarek, RL Thornberg, SM AF Jarek, RL Thornberg, SM TI Hazards of dichlorosilane exhaust deposits from the high-temperature oxide process as determined by FT-ICR mass spectrometry SO IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING LA English DT Article DE chemistry; ions; mass spectroscopy; occupational health and safety; pumps; safety ID SEQUENTIAL CLUSTERING REACTIONS; DISILANE; GROWTH; SILANE; WATER; SIH3+; SID4; IONS AB Gas samples from the exhaust system of tools employing dichlorosilane (DCS) in high temperature oxide (HTO) deposition that produced flammable solid deposits have been analyzed by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry, Exact mass determinations by the high-resolution FT-ICR allowed the identification of various polysiloxane species present in such an exhaust flow. Ion-molecule reactions of dichlorosilyl cation with water and DCS indicate the preferred reaction pathway is disiloxane formation through HCl loss, a precursor to the highly flammable polysiloxanes that were identified in the gaseous exhaust and in exhaust deposits. Minimization of these hazardous deposits is discussed with respect to water contamination, dilution factor, and water scrubbing of the HTO exhaust. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jarek, RL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 18 TC 0 Z9 0 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 0894-6507 J9 IEEE T SEMICONDUCT M JI IEEE Trans. Semicond. Manuf. PD FEB PY 2001 VL 14 IS 1 BP 20 EP 25 DI 10.1109/66.909651 PG 6 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 409BG UT WOS:000167364200003 ER PT J AU Allen, RA Headley, TJ Everist, SC Ghoshtagore, RN Cresswell, MW Linholm, LW AF Allen, RA Headley, TJ Everist, SC Ghoshtagore, RN Cresswell, MW Linholm, LW TI High-resolution transmission electron microscopy calibration of critical dimension (CD) reference materials SO IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING LA English DT Article DE critical dimension; linewidth; reference materials; semiconductor process metrology ID SILICON; WIDTH AB The National Institute of Standards and Technology and Sandia National Laboratories have developed a procedure for producing and calibrating critical dimension (CD), or linewidth, reference materials. These reference materials will be used to calibrate metrology instruments used in semiconductor manufacturing. The reference features, with widths down to 100 nm, are produced in monocrystalline silicon with all feature edges aligned to specific crystal planes, A two-part calibration of these linewidths is used: the primary calibration, with accuracy to within a few lattice plane thicknesses, is accomplished by counting the lattice planes across the sample as-imaged through use of high-resolution transmission electron microscopy, The secondary calibration is the high-precision electrical CD technique. In this paper, we describe the calibration procedure for these reference materials and estimate the related uncertainties. C1 Natl Inst Stand & Technol, Div Semicond Elect, Gaithersburg, MD 20899 USA. Sandia Natl Labs, Microstruct Characterizat Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Adv Silicon R&D Dept, Albuquerque, NM 87185 USA. RP Allen, RA (reprint author), Natl Inst Stand & Technol, Div Semicond Elect, Gaithersburg, MD 20899 USA. NR 16 TC 19 Z9 19 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 FEB PY 2001 VL 14 IS 1 BP 26 EP 31 DI 10.1109/66.909652 PG 6 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 409BG UT WOS:000167364200004 ER PT J AU Demura, M Suga, Y Umezawa, O Kishida, K George, EP Hirano, T AF Demura, M Suga, Y Umezawa, O Kishida, K George, EP Hirano, T TI Fabrication of Ni3Al thin foil by cold-rolling SO INTERMETALLICS LA English DT Article DE nickel aluminides; based on Ni3Al; brittleness and ductility; crystallographic texture; recrystallization and recovery; rolling ID ROOM-TEMPERATURE DUCTILITY; STOICHIOMETRIC NI3AL; UNIDIRECTIONAL SOLIDIFICATION; SINGLE-CRYSTAL; TEXTURE; RECRYSTALLIZATION; IMPROVEMENT; STRESS AB Thin foils of stoichiometric Ni3Al with thicknesses ranging from 57 to 315 mum were successfully fabricated by heavily cold-rolling without intermediate annealing, Starting materials were produced by directional solidification using the floating zone method. The total reduction in thickness obtained was as much as 95.5%. This high rolling ductility is considered to be due to the monocrystalline or near monocrystalline form of the starting materials. X-ray pole figures showed the formation of {110} rolling texture. This {110} texture is considered to develop mainly as a result of compressive deformation normal to the rolling plane. The foils recrystallized at temperatures over 1273 K had some tensile ductility (3.0-14.6%) at room temperature in air, in contrast to the usual brittleness of polycrystalline Ni3Al. Electron back scatter diffraction measurements revealed that low angle and Sigma3 coincidence site lattice boundaries, which are considered to be crack-resistant, comprised 41-84% of the total grain boundary area in the recrystallized foils. This large fraction is probably a chief cause of the observed ductility. These results demonstrate that it may be possible to utilize Ni3Al thin foils as lightweight, high-temperature structural materials, e.g. honeycomb structures. (C) 2001 Elsevier Science Ltd. hll rights reserved. C1 Natl Res Inst Met, Tsukuba, Ibaraki 3050047, Japan. Nippon Cross Rolling Corp, Chiba 2970026, Japan. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Demura, M (reprint author), Natl Res Inst Met, 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan. RI UMEZAWA, Osamu/C-9702-2012; George, Easo/L-5434-2014; KISHIDA, Kyosuke/M-7258-2015; OI UMEZAWA, Osamu/0000-0003-0380-1885; KISHIDA, Kyosuke/0000-0003-0391-5022; Demura, Masahiko/0000-0002-7308-3041 NR 25 TC 58 Z9 58 U1 0 U2 10 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 J9 INTERMETALLICS JI Intermetallics PD FEB PY 2001 VL 9 IS 2 BP 157 EP 167 DI 10.1016/S0966-9795(00)00121-7 PG 11 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 400CX UT WOS:000166852000008 ER PT J AU Holcomb, DJ Rudnicki, JW AF Holcomb, DJ Rudnicki, JW TI Inelastic constitutive properties and shear localization in Tennessee marble SO INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS LA English DT Article DE shear localization; constitutive properties; marble; plane strain ID PLANE-STRAIN; ROCK; COMPRESSION; DEFORMATION; BIFURCATION; BRITTLE; SAND AB The inelastic response of Tennessee marble is modelled by an elastic plastic constitutive relation that includes pressure dependence of yield, strain-softening and inelastic volume strain (dilatancy). Data from 12 axisymmetric compression tests at confining pressures from 0 to 100 MPa are used to determine the dependence of the yield function and plastic potential, which are different, on the first and second stress invariants and the accumulated inelastic shear strain. Because the data requires that the strain at peak stress depends on the mean stress, the locus of peak stresses is neither a yield surface nor a failure envelope, as is often assumed. Based on the constitutive model and Rudnicki and Rice criterion, localization is not predicted to occur in axisymmetric compression although faulting is observed in the tests. The discrepancy is likely due to the overly stiff response of a smooth yield surface model to abrupt changes in the pattern of straining. The constitutive model determined from the axisymmetric compression data describes well the variation of the in-plane stress observed in a plane strain experiment. The out-of-plane stress is not modelled well, apparently because the inelastic normal strain in this direction is overpredicted. In plane strain, localization is predicted to occur close to peak stress, in good agreement with the experiment. Observation of localization on the rising portion of the stress-strain curve in plane strain does not, however, indicate prepeak localization. Because of the rapid increase of mean stress in plane strain, the stress-strain curve can be rising while the shear stress versus shear strain curve at constant mean stress is falling (negative hardening modulus). Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Northwestern Univ, Evanston, IL 60208 USA. RP Holcomb, DJ (reprint author), Sandia Natl Labs, POB 5000,MS 0751, Albuquerque, NM 87185 USA. RI Rudnicki, John/B-7088-2009 NR 25 TC 15 Z9 16 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0363-9061 J9 INT J NUMER ANAL MET JI Int. J. Numer. Anal. Methods Geomech. PD FEB PY 2001 VL 25 IS 2 BP 109 EP 129 DI 10.1002/nag.121 PG 21 WC Engineering, Geological; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 426BN UT WOS:000168329800001 ER PT J AU Guo, YJ Weitsman, YJ AF Guo, YJ Weitsman, YJ TI A modified specimen for evaluating the mixed mode fracture toughness of adhesives SO INTERNATIONAL JOURNAL OF FRACTURE LA English DT Article DE adhesives; mixed mode fracture; toughness; fracture testing AB This article introduces a specimen geometry that allows the separation of fracture energy release rates G(I) and G(II) in adhesively joined beams made of disparate materials. The analysis is based upon a Green's functions formulation for shear deformable beams and circumvents the need to employ finite element computations. The current method results in a system of non-singular integral equations, that can be discretized and reduced to a system of algebraic equations which may be solved by common numerical techniques. The analysis accounts for the dimensions and properties of the adhesive and provides results for a wide range of G(I), G(II) and their ratio. Those results agree with finite element computational values to within less than 4%. C1 Univ Tennessee, Dept Mech & Aerosp Engn & Engn Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Engn Technol, Oak Ridge, TN 37831 USA. RP Weitsman, YJ (reprint author), Oak Ridge Natl Lab, Div Engn Technol, Mail Stop 8051, Oak Ridge, TN 37831 USA. NR 10 TC 5 Z9 5 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0376-9429 J9 INT J FRACTURE JI Int. J. Fract. PD FEB PY 2001 VL 107 IS 3 BP 201 EP 234 DI 10.1023/A:1007618718262 PG 34 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA 391LZ UT WOS:000166358600001 ER PT J AU Evans, G Greif, R AF Evans, G Greif, R TI Characterization of energy transport by mass diffusion including an application to elliptic channel flow SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; BOUNDARY LAYER; DUFOUR; SORET AB Energy transport in diffusing systems is studied with special attention devoted to the transport that occurs as a result of mass diffusion, Sigma c(pk)(j) over bar (k) . delT. Dimensionless parameters are presented for determining the importance of this transport mechanism; as an example of the application to heat and mass transfer, mixing of a binary pas in a heated, elliptic channel flow is studied. It is shown that the energy transport by mass diffusion can be an important transport mechanism which should be considered in non-isothermal systems, e.g. in CVD processes where it has often been neglected. The literature also refers ro the divergence of the energy Aux by species interdiffusion. del . (q) over bar ((d)) = del . Sigma h(k)(j) over bar (k). It is pointed out that this term depends on the enthalpy datum states of the species. Therefore, neglecting this term in the energy equation requires that another term also be: neglected so that the resulting energy equation is independent of the enthalpy datum states. Neglecting only the divergence of the energy flux by species interdiffusion would be incorrect because the resulting energy equation would then (incorrectly) depend on the enthalpy datum stares. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. RP Evans, G (reprint author), Sandia Natl Labs, MS 9042,POB 969, Livermore, CA 94550 USA. EM evans@sandia.gov NR 18 TC 3 Z9 3 U1 0 U2 0 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 FEB PY 2001 VL 44 IS 4 BP 753 EP 761 DI 10.1016/S0017-9310(00)00135-6 PG 9 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA 394NL UT WOS:000166530100006 ER PT J AU Sebastian, PJ Matthews, NR Mathew, X Pattabi, M Turner, J AF Sebastian, PJ Matthews, NR Mathew, X Pattabi, M Turner, J TI Photoelectrochemical characterization of SiC SO INTERNATIONAL JOURNAL OF HYDROGEN ENERGY LA English DT Article; Proceedings Paper CT 3rd International Symposium on New Materials, Renewable Energy and Environment CY AUG 29-SEP 02, 1999 CL CANCUN, MEXICO DE SiC; KOH; Na(2)SO(3); hydrogen; photoelectrochemical system ID HYDROGEN-PRODUCTION; SOLAR-CELLS; SINGLE AB The current-voltage (I-V) studies for p-SiC in KOH and n-SiC in Na(2)SO(3) in a two-electrode configuration indicated that SiC-based photoelectrochemical systems can be a possibility for water splitting. With illumination there is appreciable photocurrent generation at the semiconductor-electrolyte interface, which correspond to water splitting to form hydrogen and oxygen at the respective electrodes. The C-V analysis gave an idea about the hat-band potential and carrier concentration. (C) 2000 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Nacl Autonoma Mexico, Energy Res Ctr, Solar Energy Lab, Photovolta Syst Grp, Temixco 62580, Morelos, Mexico. NREL, Golden, CO USA. RP Sebastian, PJ (reprint author), Univ Nacl Autonoma Mexico, Energy Res Ctr, Solar Energy Lab, Photovolta Syst Grp, Temixco 62580, Morelos, Mexico. EM sjp@mazatl.cie.unam.mx NR 12 TC 10 Z9 10 U1 2 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-3199 J9 INT J HYDROGEN ENERG JI Int. J. Hydrog. Energy PD FEB PY 2001 VL 26 IS 2 BP 123 EP 125 DI 10.1016/S0360-3199(00)00047-1 PG 3 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA 391QM UT WOS:000166366700003 ER PT J AU Khaselev, O Bansal, A Turner, JA AF Khaselev, O Bansal, A Turner, JA TI High-efficiency integrated multijunction photovoltaic/electrolysis systems for hydrogen production SO INTERNATIONAL JOURNAL OF HYDROGEN ENERGY LA English DT Article; Proceedings Paper CT 3rd International Symposium on New Materials, Renewable Energy and Environment CY AUG 29-SEP 02, 1999 CL CANCUN, MEXICO ID SEMICONDUCTING PHOTOELECTRODES; SPLITTING WATER; SOLAR-CELLS AB In this study, two integrated PV/electrolysis systems were studied. An integrated PV/electrolysis device is a device where the PV system and the electrolyser are combined into a single system. In the case studied here, the areas of the PV device and the electrolyzer are identical. Multijunction photovoltaic (PV)/electrolysis configurations were investigated, and a high solar-to-hydrogen conversion efficiency cell demonstrated. The energy diagram of the configuration has been evaluated and exemplified with n/p, n/p-GalnP/GaAs(Pt)/KOH electrolyte and triple-junction p-i-n a-Si(Pt)/KOH electrolyte photovoltaic/electrolysis cells. The efficiency of the cells was determined based on the short-circuit photocurrent. Measurements were obtained both indoors under 100-mW/cm(2) insolation, and outdoors. For the a-Si system, a 7.8% solar-to-hydrogen conversion efficiency was demonstrated. For the GaAs/GaInP2 system, the solar-to-hydrogen conversion efficiency was over 16%. Published by Elsevier Science Ltd on behalf of the International Association for Hydrogen Energy. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Turner, JA (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Schaff, William/B-5839-2009 NR 19 TC 167 Z9 168 U1 7 U2 92 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-3199 J9 INT J HYDROGEN ENERG JI Int. J. Hydrog. Energy PD FEB PY 2001 VL 26 IS 2 BP 127 EP 132 DI 10.1016/S0360-3199(00)00039-2 PG 6 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA 391QM UT WOS:000166366700004 ER PT J AU Pugh, CE AF Pugh, CE TI Untitled SO INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING LA English DT Editorial Material C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Pugh, CE (reprint author), Oak Ridge Natl Lab, POB 2009,Mail Stop 8063, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0308-0161 J9 INT J PRES VES PIP JI Int. J. Pressure Vessels Pip. PD FEB-MAR PY 2001 VL 78 IS 2-3 BP 67 EP 67 DI 10.1016/S0308-0161(01)00020-5 PG 1 WC Engineering, Multidisciplinary; Engineering, Mechanical SC Engineering GA 444VF UT WOS:000169420200001 ER PT J AU Dickson, TL Malik, SNM AF Dickson, TL Malik, SNM TI An updated probabilistic fracture mechanics methodology for application to pressurized thermal shock SO INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING LA English DT Article; Proceedings Paper CT Meeting of the International-Atomic-Energy-Agency CY JUL 18-20, 2000 CL ROCKVILLE, MARYLAND SP Int Atom Energy Agcy DE probabilistic fracture mechanics; PRA; thermal hydraulics pressure vessels; fracture toughness; flaw characterization AB The US Nuclear Regulatory Commission (NRC) is, in concert with the US nuclear industry, currently revisiting its rule and analysis requirements for pressurized thermal shock (PTS) scenarios. This paper provides an overview of an updated probabilistic risk analysis (PRA) methodology that is continuing to evolve as part of that effort. The evolution process includes a careful assessment of recent advancements that have been made in the various parts of the computational methodologies. The process also involves interactions between experts in relevant disciplines (thermal hydraulics, PRA, materials, fracture mechanics, and non-destructive and destructive examination). Representatives include staff members from the USNRC staff, research laboratories, and the nuclear industry. The updated methodology is being integrated into the FAVOR (Fracture Analysis of Vessels: Oak Ridge) computer code for application to re-examine the adequacy of the current regulations and to determine if the updates provide sufficient technical bases for revisions. This paper also discusses recent modifications to the probabilistic fracture mechanics (PFM) methodology that is central to FAVOR. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Computat Phys & Engn Div, Oak Ridge, TN 37831 USA. RP Dickson, TL (reprint author), Oak Ridge Natl Lab, Computat Phys & Engn Div, POB 2009,Bldg 9204-1,MS-8056,Rm 206, Oak Ridge, TN 37831 USA. NR 23 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0308-0161 J9 INT J PRES VES PIP JI Int. J. Pressure Vessels Pip. PD FEB-MAR PY 2001 VL 78 IS 2-3 BP 155 EP 163 DI 10.1016/S0308-0161(01)00032-1 PG 9 WC Engineering, Multidisciplinary; Engineering, Mechanical SC Engineering GA 444VF UT WOS:000169420200009 ER PT J AU Williams, PT Bowman, KO Bass, BR Dickson, TL AF Williams, PT Bowman, KO Bass, BR Dickson, TL TI Weibull statistical models of K-Ic/K-Ia fracture toughness databases for pressure vessel steels with an application to pressurized thermal shock assessments of nuclear reactor pressure vessels SO INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING LA English DT Article; Proceedings Paper CT Meeting of the International-Atomic-Energy-Agency CY JUL 18-20, 2000 CL ROCKVILLE, MARYLAND SP Int Atom Energy Agcy AB This paper presents new statistical representations of recently extended fracture toughness K-Ic, and K-Ia, databases for pressure vessel steels. These models were developed by the Heavy Section Steel Technology program at Oak Ridge National Laboratory in support of the current effort by the U.S. Nuclear Regulatory Commission to update its regulatory guidance for pressurized-thermal-shock (PTS) transients in nuclear reactor pressure vessels. The Weibull distribution, with two of its parameters calculated by the Method of Moments point-estimation technique, forms the basis for the new statistical models. An application of the new K-Ic/K-Ia models, as implemented in the FAVOR probabilistic fracture mechanics computer program, is also presented for three PTS transients. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Williams, PT (reprint author), Oak Ridge Natl Lab, POB 2009,bldg 9204-1,MS-8056,Rm 213A, Oak Ridge, TN 37831 USA. NR 39 TC 13 Z9 16 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0308-0161 J9 INT J PRES VES PIP JI Int. J. Pressure Vessels Pip. PD FEB-MAR PY 2001 VL 78 IS 2-3 BP 165 EP 178 DI 10.1016/S0308-0161(01)00031-X PG 14 WC Engineering, Multidisciplinary; Engineering, Mechanical SC Engineering GA 444VF UT WOS:000169420200010 ER PT J AU Bass, BR Pugh, CE Sievers, J Schulz, H AF Bass, BR Pugh, CE Sievers, J Schulz, H TI Overview of the international comparative assessment study of pressurized thermal-shock in reactor pressure vessels (RPV PTS ICAS) SO INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING LA English DT Article; Proceedings Paper CT Meeting of the International-Atomic-Energy-Agency CY JUL 18-20, 2000 CL ROCKVILLE, MARYLAND SP Int Atom Energy Agcy DE pressure vessels; thermal shock; fracture mechanics; thermal-hydraulics; comparative assessments; international AB This paper summarizes the recently completed International Comparative Assessment Study of Pressurized Thermal-Shock in Reactor Pressure Vessels (RPV PTS ICAS). The ICAS project brought together international experts to perform comparative evaluations of methodologies employed in the assessment of RPV integrity under prototypical PTS conditions. ICAS grew out of a strong interest expressed by the participants to proceed with further evaluations after completion of the earlier FALSIRE II project. FALSIRE focused on evaluation of structural analysis and fracture assessment methods on the basis of experimental and analytical results. The ICAS problem statement defined transient thermal-mechanical conditions postulated to result from loss-of-coolant accidents in a Western type four-loop RPV with cladding on the inner surface. The primary focus was on the behavior of relatively shallow cracks located under and through the cladding. The assessment activities were divided into three tasks: Deterministic Fracture Mechanics (DFM), Probabilistic Fracture Mechanics (PFM) and Thermal-Hydraulic Mixing (TI IM). The results showed that a best-estimate methodology for RPV integrity assessment could benefit from a reduction of the uncertainties in each phase of the process. Within the DFM task, where account was taken of material properties and boundary conditions, reasonable agreement was obtained in linear-elastic and elastic-plastic analyses. Results from linear-elastic and J-estimation analyses were shown to provide conservative estimates of peak crack driving force when compared with those from complex 3D finite element analyses. For the PFM task, linear-elastic solutions were again shown to be conservative with respect to elastic-plastic solutions (by a factor of 2 to 4). Scatter in solutions obtained using the same computer code was generally attributable to differences in input parameters, e.g. standard deviations for the initial value of RTNDT, as well as for nickel and copper content. In the THM task, while there was a high degree of scatter during the early part of the transient, reasonable agreement was obtained during the latter part of the transient. Generally, the scatter was due to differences in analytical approaches used by the participants, which included correlation-based engineering methods, system codes and three-dimensional computational fluids dynamics codes. Based on concluding discussions from ICAS participants, a project is being organized to develop a computer software tool named QUAMET (acronym for QUALification METhodology) for future use in qualifying codes and analysts engaged in the structural integrity assessment of RPVs. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Bass, BR (reprint author), Oak Ridge Natl Lab, POB 2009,Bldg 9204-1,MS-8056,Rm 213B, Oak Ridge, TN 37831 USA. NR 6 TC 6 Z9 8 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0308-0161 J9 INT J PRES VES PIP JI Int. J. Pressure Vessels Pip. PD FEB-MAR PY 2001 VL 78 IS 2-3 BP 197 EP 211 DI 10.1016/S0308-0161(01)00030-8 PG 15 WC Engineering, Multidisciplinary; Engineering, Mechanical SC Engineering GA 444VF UT WOS:000169420200013 ER PT J AU Lee, HK Simunovic, S AF Lee, HK Simunovic, S TI A damage constitutive model of progressive debonding in aligned discontinuous fiber composites SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article DE damage constitutive model; elastoplastic behavior; progressive debonding; Weibull's probability function ID MODULI; INHOMOGENEITIES AB A micromechanical damage constitutive model is presented to predict the overall elastoplastic behavior and damage evolution in aligned discontinuous fiber polymer composites (AFPCs). In an attempt to estimate the overall elastoplastic-damage responses, an effective yield criterion is micromechanically derived based on the ensemble-volume averaging process and first-order (noninteracting) effects of eigenstrains stemming from the existence of (prolate) spheroidal fibers. The proposed effective yield criterion, in conjunction with the assumed overall associative plastic flow rule and hardening law, provides analytical foundation for the estimation of effective elastoplastic behavior of ductile matrix composites. Uniaxial elastoplastic stress-strain behavior of AFPCs is also investigated. An evolutionary interfacial debonding is subsequently employed in accordance with Weibull's probability function to characterize the varying probability of fiber debonding. Finally, the present damage model is compared with Halpin-Tsai's bounds for stiffness predictions and is applied to uniaxial loading to illustrate the damage behavior of AFPCs. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. RP Lee, HK (reprint author), Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. RI Lee, Haeng Ki/C-1640-2011 NR 28 TC 37 Z9 37 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD FEB PY 2001 VL 38 IS 5 BP 875 EP 895 DI 10.1016/S0020-7683(00)00060-3 PG 21 WC Mechanics SC Mechanics GA 391YX UT WOS:000166384800008 ER PT J AU Reedy, ED Guess, TR AF Reedy, ED Guess, TR TI Rigid square inclusion embedded within an epoxy disk: asymptotic stress analysis SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article DE corner; cracking; epoxy; fracture; inclusion; stress singularity; stress intensity factor ID INTENSITY FACTOR PREDICTION; INTERFACE CORNER; FRACTURE INITIATION; TENSILE-STRENGTH; SHARP NOTCHES; JOINT; FIELD AB The asymptotically singular stress state found at the tip of a rigid, square inclusion embedded within a thin, linear elastic disk has been determined for both uniform cooling and an externally applied pressure. Since these loadings are symmetric, the singular stress held is characterized by a single stress intensity factor K-a, and the applicable K-a calibration relationship has been determined for both a fully bonded inclusion and an unbonded inclusion with frictionless sliding. A lack of interfacial bonding has a profound effect on inclusion-tip stress fields. When the inclusion is fully bonded, radial compression dominates in the region directly in front of the inclusion tip and there is negligible tensile hoop stress. When the inclusion is unbonded the radial stress at the inclusion tip is again compressive, but now the hoop tensile stress is of equal magnitude. Consequently, an epoxy disk containing an unbonded inclusion appears to be more likely to crack when cooled than a disk containing a fully bonded inclusion. Plastic-plastic calculations show that when the inclusion is unbonded, encapsulant yielding has a significant effect on the inclusion-tip stress state. Yielding relieves stress parallel to the interface and greatly reduces the radial compressive stress in front of the inclusion. As a result, the encapsulant is subjected to a nearly uniaxial tensile stress at the inclusion tip. For a typical high-strength epoxy, the calculated yield zone is embedded within the region dominated by the elastic hoop stress singularity. A limited number of tests have been carried out to determine if encapsulant cracking can be induced by cooling a specimen fabricated by molding a square, steel insert within a thin epoxy disk. Test results are in qualitative agreement with analysis. Cracks developed only in disks with mold-released inserts, and the tendency for cracking increased with inclusion size. (C) 2001 Published by Elsevier Science Ltd. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Reedy, ED (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 8 Z9 8 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD FEB PY 2001 VL 38 IS 8 BP 1281 EP 1293 DI 10.1016/S0020-7683(00)00087-1 PG 13 WC Mechanics SC Mechanics GA 396JD UT WOS:000166631800002 ER PT J AU Venkatesan, C Jin, GP Chyu, MC Zheng, JX Chu, TY AF Venkatesan, C Jin, GP Chyu, MC Zheng, JX Chu, TY TI Measurement of thermophysical properties of polyurethane foam insulation during transient heating SO INTERNATIONAL JOURNAL OF THERMAL SCIENCES LA English DT Article DE inverse heat conduction analysis; thermal conductivity; heat capacity AB Thermal conductivity and heat capacity of polyurethane foam insulation of 374 kg.m(-3) density were measured up to 200 degreesC. Thermal conductivity and heat capacity were determined by transient temperature data taken across the foam specimen when one surface was subjected to a uniform heat flux input. The transient temperature data were then processed by a parameter estimation computer code to determine the effective thermal conductivity and heat capacity. Linear thermal conductivity and heat capacity variations with temperature were determined by providing the property values at two different temperatures. Analyses for sequential estimates, residuals, sensitivity coefficients were conducted for all property data obtained to assure accuracy. The results were compared with published data as well as an existing model. It was found that the existing model for thermal conductivity of foam materials tends to underpredict the experimental data. (C) 2001 Editions scientifiques et medicales Elsevier SAS. C1 Texas Tech Univ, Dept Mech Engn, Lubbock, TX 79409 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chyu, MC (reprint author), Texas Tech Univ, Dept Mech Engn, Lubbock, TX 79409 USA. NR 14 TC 8 Z9 8 U1 0 U2 5 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1290-0729 J9 INT J THERM SCI JI Int. J. Therm. Sci. PD FEB PY 2001 VL 40 IS 2 BP 133 EP 144 PG 12 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 411RB UT WOS:000167512100003 ER PT J AU Ortiz, TM Groll, EA Meyer, BA AF Ortiz, TM Groll, EA Meyer, BA TI Thermodynamic analysis of a heat-driven metal hydride cogeneration cycle SO INTERNATIONAL JOURNAL OF THERMAL SCIENCES LA English DT Article DE cogeneration; thermodynamics; finite time; first law; second law; hydride; hydrogen; HYCSOS ID CARNOT ENGINE AB A heat-driven metal hydride cogeneration cycle has been analyzed using classical first and second law analysis as well as finite-time thermodynamics. Second law analysis introduces important limitations on operating conditions not previously mentioned in the literature. The system being investigated is based on a cycle developed at Brookhaven National Laboratory. Predicted performance is compared to data from two other hydride power systems, HYCSOS (developed at Argonne National Laboratory) and a system developed by Bomin Solar, GmbH. Power generated per kg of hydridable alloy was highest for the present cycle (0.11 kW.kg(-1)) while useful heat or cold rates were highest for the HYCSOS cycle (0.30 kW.kg(-1)) and the system developed by Bomin Solar (0.30 kW.kg(-1)). Fuel-use efficiencies were highest for the present cycle (0.23), while second law efficiencies were highest for HYCSOS (0.60). Power and efficiency diagrams based on the finite temperature difference between the hydride bed and external heat transfer fluid are also presented. (C) 2001 Editions scientifiques et medicales Elsevier SAS. C1 Purdue Univ, Sch Mech Engn, Ray W Herrick Labs 1077, W Lafayette, IN 47907 USA. Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, Los Alamos, NM 87545 USA. RP Groll, EA (reprint author), Purdue Univ, Sch Mech Engn, Ray W Herrick Labs 1077, W Lafayette, IN 47907 USA. NR 17 TC 1 Z9 1 U1 1 U2 1 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1290-0729 J9 INT J THERM SCI JI Int. J. Therm. Sci. PD FEB PY 2001 VL 40 IS 2 BP 165 EP 172 DI 10.1016/S1290-0729(00)01205-9 PG 8 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 411RB UT WOS:000167512100006 ER PT J AU Davis, HA Keinigs, RK Anderson, WE Atchison, WL Bartsch, RR Benage, JF Ballard, EO Bowman, DW Cochrane, JC Ekdahl, CA Elizondo, JM Faehl, RJ Fulton, RD Gribble, RF Guzik, JA Kyrala, GA Miller, RB Nielsen, KE Parker, JV Parsons, WM Munson, CP Oro, DM Rodriguez, GE Rogers, HH Scudder, DW Shlachter, JS Stokes, JL Taylor, AJ Trainor, RJ Turchi, PJ Wood, BP AF Davis, HA Keinigs, RK Anderson, WE Atchison, WL Bartsch, RR Benage, JF Ballard, EO Bowman, DW Cochrane, JC Ekdahl, CA Elizondo, JM Faehl, RJ Fulton, RD Gribble, RF Guzik, JA Kyrala, GA Miller, RB Nielsen, KE Parker, JV Parsons, WM Munson, CP Oro, DM Rodriguez, GE Rogers, HH Scudder, DW Shlachter, JS Stokes, JL Taylor, AJ Trainor, RJ Turchi, PJ Wood, BP TI The atlas high-energy density physics project SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article DE high-energy density liners; pulsed power; high current; dense plasmas AB Atlas is a pulsed-power facility under development at Los Alamos National Laboratory to drive high-energy density experiments. Atlas will be operational in the summer of 2000 and is optimized for the study of dynamic material properties, hydrodynamics, and dense plasmas under extreme conditions. Atlas is designed to implode heavy-liner loads in a z-pinch configuration. The peak current of 30 MA is delivered in 4 mus. A typical Atlas liner is a 47-gram-aluminum cylinder with similar to4-cm radius and 4-cm length. Three to five MJ of kinetic energy will be delivered to the load. Using composite layers and a variety of interior target designs, a wide variety of experiments in similar to cm(3) volumes will be performed. Atlas applications, machine design, and the status of the project are reviewed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Davis, HA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Rodriguez, George/G-7571-2012 OI Rodriguez, George/0000-0002-6044-9462 NR 8 TC 6 Z9 6 U1 1 U2 7 PU INST PURE APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG, 4-24-8 SHINBASHI, MINATO-KU TOKYO, 105-004, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PD FEB PY 2001 VL 40 IS 2B BP 930 EP 934 DI 10.1143/JJAP.40.930 PG 5 WC Physics, Applied SC Physics GA 426NT UT WOS:000168355800003 ER PT J AU Derewenda, U Li, J Dauter, Z Mueller, GA Rule, GS Derewenda, ZS Benjamin, DC AF Derewenda, U Li, J Dauter, Z Mueller, GA Rule, GS Derewenda, ZS Benjamin, DC TI Crystal structure of Der p 2, a major dust mite allergen SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Meeting Abstract C1 Univ Virginia, Charlottesville, VA USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Toronto, Hosp Sick Children, Toronto, ON M5G 1X8, Canada. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RI Rule, Gordon/Q-2422-2015 OI Rule, Gordon/0000-0002-4396-3363 NR 4 TC 2 Z9 2 U1 0 U2 0 PU MOSBY, INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD FEB PY 2001 VL 107 IS 2 SU S MA 417 BP S126 EP S126 PG 1 WC Allergy; Immunology SC Allergy; Immunology GA 405RE UT WOS:000167172300416 ER PT J AU Ramirez, A Daily, W AF Ramirez, A Daily, W TI Electrical imaging at the large block test - Yucca Mountain, Nevada SO JOURNAL OF APPLIED GEOPHYSICS LA English DT Article DE electrical resistance tomography; temperature; yucca mountain ID INDUCED-POLARIZATION DATA; TOPOPAH SPRING TUFF; RESISTIVITY TOMOGRAPHY; COMPUTED-TOMOGRAPHY; INVERSION AB A monolithic block of densely welded tuff was excavated from a site on Fran Ridge near Yucca Mountain, Nevada so that coupled thermohydrological processes could be studied in a controlled, in situ experiment. A series of heaters were placed in a horizontal plane about 3 m from the top of the 3 m x 3 m x 4.5-m high block. Temperatures were measured at many points within and on the block surface and a suite of other measurements were taken to define the thermal and hydrologic response. Electrical resistance tomography (ERT) was used to map two-dimensional images of moisture content changes along four planes in the block. The ERT images clearly delineate the drying and wetting of the rockmass during the 13 months of heating and subsequent 6 months of cool down. The main feature is a prominent dry zone that forms around the heaters then gradually disappears as the rock cools down. Other features include linear anomalies of decreasing moisture content, which are fractures dehydrating as the block heats up. There are also examples of compact anomalies of wetting. Some of these appear to be water accumulation in fractures, which are draining condensate from the block. Others may be rainwater entering a fracture at the top of the block. During cool-down, a general rewetting is observed although this is less certain because of poor data quality during this stage of the experiment. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Daily, W (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 20 TC 16 Z9 17 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-9851 J9 J APPL GEOPHYS JI J. Appl. Geophys. PD FEB PY 2001 VL 46 IS 2 BP 85 EP 100 DI 10.1016/S0926-9851(00)00042-2 PG 16 WC Geosciences, Multidisciplinary; Mining & Mineral Processing SC Geology; Mining & Mineral Processing GA 416DE UT WOS:000167764300001 ER PT J AU Glade, SC Loffler, JF Bossuyt, S Johnson, WL Miller, MK AF Glade, SC Loffler, JF Bossuyt, S Johnson, WL Miller, MK TI Crystallization of amorphous Cu47Ti34Zr11Ni8 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID BULK METALLIC GLASSES; ZR41.2TI13.8CU12.5NI10BE22.5 ALLOY; DECOMPOSITION; NANOCRYSTALS AB The results of a study on the crystallization of amorphous Cu47Ti34Zr11Ni8 with the use of differential scanning calorimetry, transmission electron microscopy (TEM), x-ray diffraction, field ion microscopy, atom probe tomography (APT), and small-angle neutron scattering (SANS) are presented. These experimental techniques were used to characterize as-prepared samples and specimens heat treated at different temperatures around the glass transition temperature. APT and SANS show that the alloy decomposes into copper-enriched and titanium-enriched regions prior to nucleation and growth of a crystalline phase. TEM shows that the primary nucleating phase has a face centered cubic structure. (C) 2001 American Institute of Physics. C1 CALTECH, Div Engn & Appl Sci, Pasadena, CA 91125 USA. Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanal Sci Grp, Oak Ridge, TN 37831 USA. RP Glade, SC (reprint author), CALTECH, Div Engn & Appl Sci, Pasadena, CA 91125 USA. RI Bossuyt, Sven/H-5660-2012 OI Bossuyt, Sven/0000-0002-9223-735X NR 23 TC 55 Z9 57 U1 1 U2 14 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2001 VL 89 IS 3 BP 1573 EP 1579 DI 10.1063/1.1332089 PG 7 WC Physics, Applied SC Physics GA 396NX UT WOS:000166644400007 ER PT J AU Reisman, DB Toor, A Cauble, RC Hall, CA Asay, JR Knudson, MD Furnish, MD AF Reisman, DB Toor, A Cauble, RC Hall, CA Asay, JR Knudson, MD Furnish, MD TI Magnetically driven isentropic compression experiments on the Z accelerator SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID DENSE MATTER; MODEL; EQUATION; HOT AB Isentropic compression experiments (ICE) have been performed on the Z accelerator facility at Sandia National Laboratory. We describe the experimental design that used large magnetic fields to slowly compress samples to pressures in excess of 400 kbar. Velocity wave profile measurements were analyzed to yield isentropic compression equations of state (EOS). The method can also yield material strength properties. We describe magnetohydronamic simulations and results of experiments that used the ''square short'' configuration to compress copper and discuss ICE EOS experiments that have been performed with this method on tantalum, molybdenum, and beryllium. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Reisman, DB (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 23 TC 103 Z9 109 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2001 VL 89 IS 3 BP 1625 EP 1633 DI 10.1063/1.1337082 PG 9 WC Physics, Applied SC Physics GA 396NX UT WOS:000166644400014 ER PT J AU Lee, YE Norton, DP Park, C Rouleau, CM AF Lee, YE Norton, DP Park, C Rouleau, CM TI Blue photoluminescence in ZnGa2O4 thin-film phosphors SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID EMISSION; OXIDE AB The growth and properties of luminescent ZnGa2O4 thin films using pulsed laser ablation has been investigated. As-deposited films on glass and (100) MgO substrates exhibit blue-white photoluminescence with a broad emission band under ultraviolet excitation. In situ epitaxial films obtained on single crystal (100) MgO substrates possess enhanced luminescent intensity as compared to polycrystalline films on glass substrates. The enhanced luminescence in epitaxial films presumably reflects lower defect densities due to growth on low energy surfaces. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Lee, YE (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Yoon, Sejin/F-7637-2013; Rouleau, Christopher/Q-2737-2015 OI Rouleau, Christopher/0000-0002-5488-3537 NR 11 TC 40 Z9 41 U1 4 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2001 VL 89 IS 3 BP 1653 EP 1656 DI 10.1063/1.1287228 PG 4 WC Physics, Applied SC Physics GA 396NX UT WOS:000166644400018 ER PT J AU Spichkin, YI Pecharsky, VK Gschneidner, KA AF Spichkin, YI Pecharsky, VK Gschneidner, KA TI Preparation, crystal structure, magnetic and magnetothermal properties of (GdxR5-x)Si-4, where R=Pr and Tb, alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB The series of alloys (GdxTb5-x)Si-4 (x=0,2.5,3,3.5,4,4.5,5) and (GdxPr5-x)Si-4 (x=4,4.25,4.5) have been prepared. Their room temperature crystal structure has been established, and dc magnetization and ac magnetic susceptibility have been measured in the temperature range from 4.2 to 550 K and in dc magnetic fields up to 50 kOe. The magnetocaloric effect has been calculated from the magnetization data and, for one of the alloys, from the heat capacity data. The magnetocaloric effect values from the two different measurements are in excellent agreement. The (GdxTb5-x)Si-4 alloys exhibit magnetocaloric effects in low magnetic fields (<20 kOe) comparable to that of Gd metal and, therefore, they represent a new class of promising magnetic refrigerant materials. (C) 2001 American Institute of Physics. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Pecharsky, VK (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. OI Spichkin, Yury/0000-0002-6088-5395 NR 28 TC 47 Z9 48 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2001 VL 89 IS 3 BP 1738 EP 1745 DI 10.1063/1.1335821 PG 8 WC Physics, Applied SC Physics GA 396NX UT WOS:000166644400031 ER PT J AU Hsu, L Walukiewicz, W AF Hsu, L Walukiewicz, W TI Effect of polarization fields on transport properties in AlGaN/GaN heterostructures SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MODULATION-DOPED HETEROSTRUCTURES; EFFECT TRANSISTORS; ELECTRON-MOBILITY; DEFECT FORMATION; INDUCED CHARGE; GAN; INTERFACES AB We have calculated transport properties of unintentionally doped n-type AlGaN/GaN heterostructures. Using a thermodynamic model of defect formation, we have modeled the charge transfer process in such heterostructures, obtaining good agreement with experiment. The large polarization fields in the heterostructure dramatically lower the formation energy of the surface defects, leading to the observed extremely large two-dimensional electron gas concentrations. Calculations of the low temperature mobilities were also performed, showing that alloy disorder and, in some cases, interface roughness, are the dominant low-temperature carrier scattering mechanisms. At low temperatures a maximum intrinsic mobility of about 10(5) cm(2)/V s is predicted for these heterostructures. (C) 2001 American Institute of Physics. C1 Carnegie Mellon Univ, Ctr Innovat Learning, Pittsburgh, PA 15213 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Hsu, L (reprint author), Carnegie Mellon Univ, Ctr Innovat Learning, Pittsburgh, PA 15213 USA. NR 31 TC 112 Z9 118 U1 1 U2 29 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2001 VL 89 IS 3 BP 1783 EP 1789 DI 10.1063/1.1339858 PG 7 WC Physics, Applied SC Physics GA 396NX UT WOS:000166644400039 ER PT J AU Kavner, A Duffy, TS AF Kavner, A Duffy, TS TI Pressure-volume-temperature paths in the laser-heated diamond anvil cell SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID X-RAY-DIFFRACTION; V-T EQUATION; COESITE-STISHOVITE TRANSITION; SHEAR MODULUS C44; LOWER MANTLE; CASIO3 PEROVSKITE; PHASE-BOUNDARY; THERMAL PRESSURE; MELTING CURVE; OF-STATE AB The temperature, pressure, and stress conditions in the diamond anvil cell sample chamber before, during, and after laser heating are mapped by employing standard materials as in situ pressure markers. Unit cell volumes of Pt, MgO, and NaCl were monitored by synchrotron-based x-ray diffraction at temperatures between 300 and 2290 K and pressures ranging from 14 to 53 GPa. To aid in interpreting the resulting pressure-volume-temperature paths, we perform a series of model calculations of the high-temperature, high-pressure x-ray diffraction behavior of platinum subjected to a general stress state. Thermal pressure and thermal expansion effects within the laser-heated volume are observed but are not sufficient to fully explain the measured paths. Large apparent pressure changes can also result from relaxation of deviatoric stresses during heating and partial reintroduction of those stresses during quench. Deviatoric stresses, monitored from both diffraction peak widths and lattice parameter shifts as a function of (hkl), may significantly distort equation of state results if it is assumed that the sample is under hydrostatic pressure. Large-scale, nearly isothermal pressure relaxation events are observed at similar to 2000 K. It is proposed that these arise from relaxation of heated components (pressure medium, gasket, cell itself) outside of the directly laser-heated volume. (C) 2001 American Institute of Physics. C1 Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Argonne Natl Lab, Adv Photon Source, GSECARS, Sector 13, Argonne, IL 60439 USA. RP Kavner, A (reprint author), Lamont Doherty Earth Observ, 61 Rt 9W, Palisades, NY 10964 USA. EM KAVNER@LDEO.COLUMBIA.EDU RI Kavner, Abby/A-4904-2009; Duffy, Thomas/C-9140-2017 OI Duffy, Thomas/0000-0002-5357-1259 NR 46 TC 36 Z9 36 U1 0 U2 9 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 FEB 1 PY 2001 VL 89 IS 3 BP 1907 EP 1914 DI 10.1063/1.1335827 PG 8 WC Physics, Applied SC Physics GA 396NX UT WOS:000166644400058 ER PT J AU Merkulov, VI Lowndes, DH Baylor, LR AF Merkulov, VI Lowndes, DH Baylor, LR TI Scanned-probe field-emission studies of vertically aligned carbon nanofibers SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID NANOTUBE; DISPLAY AB Field emission properties of dense and sparse "forests" of randomly placed, vertically aligned carbon nanofibers (VACNFs) were studied using a scanned probe with a small tip diameter of similar to1 mum. The probe was scanned in directions perpendicular and parallel to the sample plane, which allowed for measuring not only the emission turn-on field at fixed locations but also the emission site density over large surface areas. The results show that dense forests of VACNFs are not good field emitters as they require high extracting (turn-on) fields. This is attributed to the screening of the local electric field by the neighboring VACNFs. In contrast, sparse forests of VACNFs exhibit moderate-to-low turn-on fields as well. as high emission site and current densities, and long emission lifetime, which makes them very promising for various field emission applications. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Div Instrumentat & Controls, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37831 USA. RP Merkulov, VI (reprint author), Oak Ridge Natl Lab, Div Instrumentat & Controls, Oak Ridge, TN 37831 USA. NR 17 TC 31 Z9 32 U1 1 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2001 VL 89 IS 3 BP 1933 EP 1937 DI 10.1063/1.1339860 PG 5 WC Physics, Applied SC Physics GA 396NX UT WOS:000166644400062 ER PT J AU Watanabe, Y Kang, SH Chan, JW Morris, JW Shaw, TJ Clarke, J AF Watanabe, Y Kang, SH Chan, JW Morris, JW Shaw, TJ Clarke, J TI Observation of magnetic gradients in stainless steel with a high-T(c) superconducting quantum interference device microscope SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GRADED MATERIAL; DEFORMATION; 304-STAINLESS-STEEL; TRANSFORMATION; MARTENSITE AB Superconducting quantum interference device (SQUID) microscopes may serve as useful nondestructive evaluation (NDE) tools since they can precisely measure the local magnetic field variation that can be related to the characteristics of ferromagnetic materials. To demonstrate this, we have studied magnetic functionally graded materials (FGMs) in the Fe-Cr-Ni alloy system using a high-transition-temperature (HT(c)) SQUID microscope. The FGMs were either fabricated by inhomogeneous mechanical deformation or by heat treatment in a temperature gradient. The magnetic properties of these materials were measured using the vibrating sample magnetometer technique along the deformation or the temperature gradients. The results from this technique and the microstructural properties from optical imaging are discussed in conjunction with the magnetic field images obtained from the SQUID microscope. By exploring the results, the feasibility and benefit of utilizing SQUID microscopy as a NDE tool are discussed. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, 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. Shinshu Univ, Dept Funct Machinery & Mech, Ueda, Nagano 3868567, Japan. RP Watanabe, Y (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. EM yoshimi@giptc.shinshu-u.ac.jp NR 11 TC 11 Z9 11 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2001 VL 89 IS 3 BP 1977 EP 1982 DI 10.1063/1.1334637 PG 6 WC Physics, Applied SC Physics GA 396NX UT WOS:000166644400070 ER PT J AU Barnett, RN Sun, ZW Lester, WA AF Barnett, RN Sun, ZW Lester, WA TI Improved trial wave functions in quantum Monte Carlo: Application to acetylene and its dissociation fragments SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID BENCHMARK CALCULATIONS; ELECTRONIC-STRUCTURE; FIXED-SAMPLE; RANDOM-WALK; MOLECULES; ENERGIES; C2H2; OPTIMIZATION; ALGORITHM; HYDRIDES AB Recent quantum Monte Carlo (QMC) studies of electronic structure have considered various trial function enhancements directed at improved fixed-node energies. In this study we investigate complete active space self-consistent field (CASSCF) trial functions in the diffusion Monte Carlo (DMC) method. We study longer CASSCF expansions than typically used in QMC studies and optimize correlation function parameters, basis function coefficients, and configuration state function mixing coefficients. To perform a stable, efficient wavefunction optimization, sample points are analytically obtained from an integrable probability density function or a Monte Carlo walk guided by a positive definite function. The approach is applied to acetylene and its dissociation fragments (C, CH, C-2, C2H, C2H2). For these systems 70%-90% of the correlation energy is recovered with variational MC and 91%-98% with DMC. (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 Barnett, RN (reprint author), MDL Informat Syst Inc, 14600 Catalina St, San Leandro, CA 94577 USA. NR 42 TC 13 Z9 13 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 1 PY 2001 VL 114 IS 5 BP 2013 EP 2021 DI 10.1063/1.1335596 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 397CQ UT WOS:000166676100012 ER PT J AU Dupuis, M Marquez, A AF Dupuis, M Marquez, A TI The Rys quadrature revisited: A novel formulation for the efficient computation of electron repulsion integrals over Gaussian functions SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RECURRENCE RELATIONS AB A novel formulation of the Rys quadrature algorithm for the calculation of the electron repulsion integrals over Gaussian basis functions is presented. The new algorithm is specifically designed for high contractions. As for the original Rys quadrature algorithm, the new algorithm is very efficient for high angular momentum functions. In addition it is also equally efficient for low angular momentum functions. The new algorithm takes unique advantage of (1) the numerical Rys quadrature methodology in (2) dealing with charge distributions a la McMurchie-Davidson and in (3) scaling integral blocks as a means of transferring angular momentum a la Gill-Head-Gordon-Pople. An analysis of the algorithm suggests very favorable floating-point operation counts. (C) 2001 American Institute of Physics. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Sevilla, Dept Chem, Seville, Spain. RP Dupuis, M (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, K8-91,POB 999,Battelle Blvd, Richland, WA 99352 USA. RI Marquez, Antonio/M-2878-2014 OI Marquez, Antonio/0000-0001-6699-064X NR 17 TC 25 Z9 25 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 1 PY 2001 VL 114 IS 5 BP 2067 EP 2078 DI 10.1063/1.1336541 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 397CQ UT WOS:000166676100018 ER PT J AU Parks, EK Kerns, KP Riley, SJ AF Parks, EK Kerns, KP Riley, SJ TI The structure of Ni-46, Ni-47, and Ni-48 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID BINDING MOLECULAR-DYNAMICS; TRANSITION-METAL CLUSTERS; SMALL NICKEL CLUSTERS; NI CLUSTERS; MAGNETIC-PROPERTIES; COBALT CLUSTERS; IRON CLUSTERS; FE CLUSTERS; ADSORPTION; CO AB The geometrical structures of Ni-46, Ni-47, and Ni-48 are investigated by the chemical probe method using molecular nitrogen as the probe molecule. Nitrogen saturation levels are determined and found to be consistent with cluster structures derived from two geometries, one having face-centered-cubic (fcc) packing and the other fcc/hcp (hexagonal-close-packed) layered packing. The fcc-based structures provide the best overall agreement with the experimental measurements. The saturation levels are inconsistent with icosahedral or decahedral packing, a structure found for Ni-49 and larger clusters in earlier experiments. The change in cluster structure between Ni-48 and Ni-49 (most likely from fcc to icosahedral packing) is clearly evident in the nitrogen adsorption experiments at both low and high coverages, as well as with other reagent molecules. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Parks, EK (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM sjriley@anl.gov NR 39 TC 15 Z9 17 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 1 PY 2001 VL 114 IS 5 BP 2228 EP 2236 DI 10.1063/1.1338975 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 397CQ UT WOS:000166676100036 ER PT J AU Kaufman, LJ Blank, DA Fleming, GR AF Kaufman, LJ Blank, DA Fleming, GR TI Polarization selectivity in fifth-order electronically nonresonant Raman scattering from CS2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID FEMTOSECOND 2-DIMENSIONAL SPECTROSCOPY; ORIENTATIONAL CORRELATION-FUNCTIONS; OPTICAL HETERODYNE-DETECTION; TIME-RESOLVED 4-WAVE; LIQUID CS2; NONLINEAR SPECTROSCOPY; ISOTROPIC MEDIA; 5TH ORDER; INTERMOLECULAR SPECTROSCOPY; VIBRATIONAL COHERENCE AB This paper presents several experimentally collected tensor elements of the direct fifth-order Raman signal of room temperature CS2. All results were collected so as to reduce contamination from third-order cascade signals, and it is shown that while these cascade signals are of varying importance in different tensor elements, phase matching considerations are sufficient to make the direct fifth-order signal the dominant signal in every tensor element collected. We show, as predicted, that the different tensor elements appear to weight particular Liouville pathways of the direct fifth-order signal, and thus particular dynamics of the studied system, differently. The magic angle signals are shown to contain information about the intermolecular vibrational echo and to put a limit on the time scale of rephasing of the room temperature liquid. The R-yzzzzy tensor element, in conjunction with the R-yyzzzz tensor element, is shown to be useful in studying the pure dephasing and population dynamics of the liquid. From these data it appears that population dynamics occur on a much longer time scale than pure dephasing dynamics, even though this is not obvious for the intermolecular motions of a room temperature liquid that are studied here. Further, intensities and behaviors of different tensor elements of the experimental data are compared with the only detailed theory currently available that explicitly includes polarization dependence. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Kaufman, LJ (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 51 TC 63 Z9 63 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 1 PY 2001 VL 114 IS 5 BP 2312 EP 2331 DI 10.1063/1.1337042 PG 20 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 397CQ UT WOS:000166676100045 ER PT J AU Polya, DA Woolley, EM Simonson, JM Mesmer, RE AF Polya, DA Woolley, EM Simonson, JM Mesmer, RE TI The enthalpy of dilution and thermodynamics of Na2CO3(aq) and NaHCO3(aq) from T=298 K to T=523.15 K and pressure of 40 MPa SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article DE enthalpy of dilution; aqueous solutions of sodium carbonate and sodium; hydrogencarbonate ID ELEVATED-TEMPERATURES; SODIUM-CARBONATE; WATER; BICARBONATE; EQUILIBRIA; CHLORIDE; SYSTEM; 523-K; ACID AB Molar enthalpies of dilution Delta H-dil(m) of Na2CO3(aq) were measured from molality m = 1.45 mol . kg(-1) to m = 0.008 mol . kg(-1) at seven temperatures from T = 298 K to T = 523 K at the pressure p = 7 MPa, and at four temperatures from T = 371 K to T = 523 K at the pressure p = 40 MPa. Molar enthalpies of dilution Delta H-dil(m) Of NaHCO3(aq) were measured from m = 0.98 mol . kg(-1) to m = 0.007 mol . kg(-1) at the same temperatures and pressures. Hydrolysis and ionization equilibria contribute substantially to the measured enthalpies under many of the conditions of this study. Explicit consideration of these reactions, using thermodynamic quantities from previous studies, facilitates a quantitative representation of apparent molar enthalpies, activity coefficients, and osmotic coefficients with the Pitzer ion-interaction treatment over the ranges of temperature, pressure, and molality of the experiments. (C) 2001 Academic Press. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37830 USA. RP Simonson, JM (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37830 USA. OI Polya, David/0000-0002-7484-6696 NR 19 TC 9 Z9 10 U1 1 U2 8 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD FEB PY 2001 VL 33 IS 2 BP 205 EP 243 DI 10.1006/jcht.2001.0754 PG 39 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA 418ZU UT WOS:000167925600007 ER PT J AU Perkins, WG Lucero, DA AF Perkins, WG Lucero, DA TI Interpretation of actinide-distribution data obtained from non-destructive and destructive post-test analyses of an intact-core column of Culebra dolomite SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article; Proceedings Paper CT 7th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere (MIGRATION 99) CY SEP 26-OCT 01, 1999 CL LAKE TAHOE, CALIFORNIA SP Lawrence Livemore Natl Lab DE actinide; intact-core column; Culebra dolomite AB The US Department of Energy (DOE), with technical assistance from Sandia National Laboratories, has successfully received EPA certification and opened the Waste Isolation Pilot Plant (WIPP), a nuclear waste disposal facility located approximately 42 km east of Carlsbad, NM. Performance assessment (PA) analyses indicate that human intrusions by inadvertent, intermittent drilling for resources provide the only credible mechanisms for significant releases of radionuclides from the disposal system. For long-term brine releases, migration pathways through the permeable layers of rock above the Salado formation are important. Major emphasis is placed on the Culebra Member of the Rustler Formation because this is the most transmissive geologic layer overlying the WIPP site. In order to help quantify parameters for the calculated releases, radionuclide transport experiments have been carried out using intact-core columns obtained from the Culebra dolomite member of the Rustler Formation within the WIPP site. This paper deals primarily with results of analyses for Pu-241 and Am-241 distributions developed during transport experiments in one of these cores. Transport experiments were done using a synthetic brine that simulates Culebra brine at the core recovery location (the WIPP air-intake shaft (AIS)). Hydraulic characteristics (i.e., apparent porosity and apparent dispersion coefficient) for intact-core columns were obtained via experiments using the conservative tracer Na-22. Elution experiments carried out over periods of a few days with tracers U-232 and Np-239 indicated that these tracers were weakly retarded as indicated by delayed elution of the species. Elution experiments with tracers Pu-241 and Am-241 were attempted but no elution of either species has been observed to date, including experiments of many months' duration. In order to quantify retardation of the non-eluted species Pu-241 and Am-241 after a period of brine flow, non-destructive and destructive analyses of one intact-core column were carried out to determine distribution of these actinides in the rock. Analytical results indicate that the majority of the Am-241 remained very near the injection surface of the core (possibly as a precipitate), and that the majority of the Pu-241 was dispersed with a very high apparent retardation value. The Pu-241 distribution is interpreted using a single-porosity advection-dispersion model. and an approximate retardation value is reported. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, WIPP Regulatory Compliance Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, WIPP Chem & Disposal Room Proc Dept, Albuquerque, NM 87185 USA. RP Perkins, WG (reprint author), Sandia Natl Labs, WIPP Regulatory Compliance Dept, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD FEB PY 2001 VL 47 IS 2-4 BP 107 EP 116 DI 10.1016/S0169-7722(00)00141-8 PG 10 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 399ZP UT WOS:000166844400002 PM 11288568 ER PT J AU Duff, MC Hunter, DB Triay, IR Bertsch, PM Kitten, J Vaniman, DT AF Duff, MC Hunter, DB Triay, IR Bertsch, PM Kitten, J Vaniman, DT TI Comparison of two micro-analytical methods for detecting the spatial distribution of sorbed Pu on geologic materials SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article; Proceedings Paper CT 7th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere (MIGRATION 99) CY SEP 26-OCT 01, 1999 CL LAKE TAHOE, CALIFORNIA SP Lawrence Livemore Natl Lab DE micro-analytical methods; spatial distribution; sorbed Pu ID YUCCA MOUNTAIN; PLUTONIUM; TUFF; MICROAUTORADIOGRAPHY; SPECIATION; ADSORPTION; SEDIMENTS; MINERALS; SEAWATER; SORPTION AB Subsurface transport of groundwater contaminants is greatly influenced by chemical speciation, precipitation and sorption processes at the mineral-water interface. The retardation of contaminants is often greatest at boundaries between minerals and in fractures and pore spaces, The investigation of the spatial distribution of sorbed contaminants along these boundaries requires micro-analytical techniques. The sorption of dissolved Pu(V) on a natural zeolitic tuff from Yucca Mountain (NV, USA) was examined using microautoradiography (MAR), X-ray diffraction (XRD), electron microprobe (EM) techniques, and synchrotron-based micro-X-ray fluorescence (micro-SXRF). The tuff contained a heterogeneous distribution of zeolites and trace quantities of smectites, Fe oxides (hematite), and Mn oxides (ranciete), which are present as fracture fill and pore space materials. Micro-SXRF studies showed that Pu is mostly associated with bodies of smectite plus Mn oxides, which were typically elevated in Ce. Ga, Nb, Pb, Y, Ca, Ti, and Zn. Sorbed Pu was not associated with Fe-rich bodies, which were enriched in Cl and Rb. Results of the MAR studies were complementary to that of the micro-SXRF studies in that Pu was associated with similar elements in the tuff. Indirect detection of Pu by EM or micro-SXRF (by analyzing Ag developed on the MAR photoemulsion) was a more sensitive method for detecting lower levels of sorbed Pu than the direct detection of sorbed Pu via micro-SXRF in the absence of the photoemulsion. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Aiken, SC 29802 USA. Waste Isolat Pilot Plant, Carlsbad, NM 88221 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Duff, MC (reprint author), Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Drawer E, Aiken, SC 29802 USA. NR 24 TC 16 Z9 16 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD FEB PY 2001 VL 47 IS 2-4 BP 211 EP 218 DI 10.1016/S0169-7722(00)00150-9 PG 8 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 399ZP UT WOS:000166844400011 PM 11288577 ER PT J AU Arnold, T Zorn, T Zanker, H Bernhard, G Nitsche, H AF Arnold, T Zorn, T Zanker, H Bernhard, G Nitsche, H TI Sorption behavior of U(VI) on phyllite: experiments and modeling SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article; Proceedings Paper CT 7th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere (MIGRATION 99) CY SEP 26-OCT 01, 1999 CL LAKE TAHOE, CA SP Lawrence Livermore Natl Lab DE surface complexation modeling; quartz; chlorite; muscovite; albite; ferrihydrite ID URANIUM MIGRATION; FERRIHYDRITE; ADSORPTION; IONS AB The sorption of U(VI) onto low-grade metamorphic rock phyllite was modeled with the diffuse double layer model (DDLM) using the primary mineralogical constituents of phyllite, i.e. quartz, chlorite, muscovite, and albite, as input components, and as additional component, the poorly ordered Fe oxide hydroxide mineral, ferrihydrite. Ferrihydrite forms during the batch sorption experiment as a weathering product of chlorite. In this process, Fe(II). leached from the chlorite, oxidizes to Fe(III), hydrolyses and precipitates as ferrihydrite. The formation of ferrihydrite during the batch sorption experiment was identified by Mossbauer spectroscopy, showing a 2.8% increase of Fe(III) in the phyllite powder. The ferrihydrite was present as Fe nanoparticles or agglomerates with diameters ranging from 6 to 25 nm, with indications for even smaller particles. These Fe colloids were detected in centrifugation experiments of a ground phyllite suspension using various centrifugal forces. The basis for the successful interpretation of the experimental sorption data of uranyl(VI) on phyllite were: (1) the determination of surface complex formation constants of uranyl with quartz, chlorite, muscovite, albite, and ferrihydrite in individual batch sorption experiments, (2) the determination of surface acidity constants of quartz, chlorite, muscovite, and albite obtained from separate acid-base titration, (3) the determination of surface site densities of quartz, chlorite, muscovite, and albite evaluated independently of each other with adsorption isotherms, and (4) the quantification of the secondary phase ferrihydrite, which formed during the batch sorption experiments with phyllite. The surface complex formation constants and the protolysis constants were optimized by using the experimentally obtained data sets and the computer code FITEQL. Surface site densities were evaluated from adsorption isotherms at pH 6.5. C1 Forschungszentrum Rossendorf EV, Inst Radiochem, D-01314 Dresden, Germany. Univ Calif Berkeley, Gleen T Seaborg Ctr, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Gleen T Seaborg Ctr, Berkeley, CA 94720 USA. RP Arnold, T (reprint author), Forschungszentrum Rossendorf EV, Inst Radiochem, POB 510119, D-01314 Dresden, Germany. EM t.arnold@fz-rossendorf.de NR 34 TC 70 Z9 71 U1 4 U2 22 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 EI 1873-6009 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD FEB PY 2001 VL 47 IS 2-4 BP 219 EP 231 DI 10.1016/S0169-7722(00)00151-0 PG 13 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 399ZP UT WOS:000166844400012 PM 11288578 ER PT J AU Krumhansl, JL Brady, PV Anderson, HL AF Krumhansl, JL Brady, PV Anderson, HL TI Reactive barriers for Cs-137 retention SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article; Proceedings Paper CT 7th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere (MIGRATION 99) CY SEP 26-OCT 01, 1999 CL LAKE TAHOE, CALIFORNIA SP Lawrence Livemore Natl Lab DE reactive barriers; Cs-135; Cs-137 ID CESIUM SORPTION AB Cs-137 was dispersed globally by cold war activities and, more recently, by the Chernobyl accident. Engineered extraction of Cs-137 from soils and groundwaters is exceedingly difficult. Cs-137 is only 30.2 years, remediation might be more effective land less Because the half-life of costly) if Cs-137 bioavailability could be demonstrably limited for even a few decades by use of a reactive barrier. Essentially permanent isolation must be demonstrated in those few settings where high nuclear level wastes contaminated the environment with Cs-135 (half-life 2.3 x 10(-6) years) in Cs-137. Clays are potentially a low-cost barrier to Cs movement, though their long-term addition to effectiveness remains untested. To identify optimal clays for Cs retention, Cs desorption was measured for five common clays: Wyoming Montmorillonite (SWy-1), Georgia Kaolinites (KGa-1 and KGa-2), Fithian Illite (F-III), and K-Metabentonite (K-Mbt). Exchange sites were pre-saturated with 0.16 M CsCl for 14 days and readily exchangeable Cs was removed by a series of LiNO3 and LiCl washes. Washed clays were then placed into dialysis bags and the Cs release to the deionized water outside the bags measured. Release rates from 75 to 139 days for SWy-1, K-Mbt and F-III were similar; 0.017% to 0.021% sorbed Cs released per day. Both kaolinites released Cs more rapidly (0.12% to 0.05% of the sorbed Cs per day). In a second set of experiments, clays were Cs-doped for 110 days and subjected to an extreme and prolonged rinsing process. All the clays exhibited some capacity for irreversible Cs uptake. However, the residual loading was greatest on K-Mbt (similar to 0.33 wt.% Cs). Thus, this clay would be the optimal material for constructing artifical reactive barriers. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Geochem Dept MS 0750, Albuquerque, NM 87185 USA. RP Krumhansl, JL (reprint author), Sandia Natl Labs, Geochem Dept MS 0750, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 23 Z9 23 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD FEB PY 2001 VL 47 IS 2-4 BP 233 EP 240 DI 10.1016/S0169-7722(00)00152-2 PG 8 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 399ZP UT WOS:000166844400013 PM 11288579 ER PT J AU Wang, YF Papenguth, HW AF Wang, YF Papenguth, HW TI Kinetic modeling of microbially-driven redox chemistry of radionuclides in subsurface environments: coupling transport, microbial metabolism and geochemistry SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article; Proceedings Paper CT 7th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere (MIGRATION 99) CY SEP 26-OCT 01, 1999 CL LAKE TAHOE, CALIFORNIA SP Lawrence Livemore Natl Lab DE microbial metabolism; redox chemistry; radionuclide transport ID REACTIVE TRANSPORT; AQUIFER; SIMULATION; BIODEGRADATION; GROUNDWATER; SEDIMENTS; LANDFILL; DENMARK; OXYGEN; IRON AB Microbial reactions play an important role in regulating pore water chemistry as well as secondary mineral distribution in many subsurface systems and, therefore, may directly impact radionuclide migration in those systems. This paper presents a general modeling approach to couple microbial metabolism redox chemistry, and radionuclide transport in a subsurface environment. To account for the likely achievement of quasi-steady state biomass accumulations in subsurface environments, a modification to the traditional microbial growth kinetic equation is proposed. The conditions for using biogeochemical models with or without an explicit representation of biomass growth are clarified. Based on the general approach proposed in this paper, the couplings of uranium reactions with biogeochemical processes are incorporated into computer code BIORXNTRN Version 2.0. The code is then used to simulate a subsurface contaminant migration scenario, in which a water flow containing both uranium and a complexing organic ligand is recharged into an oxic carbonate aquifer. The model simulation shows that Mn and Fe oxyhydroxides may vary significantly along a flow path. The simulation also shows that uranium(VI) can be reduced and therefore immobilized in the anoxic zone created by microbial degradation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Carlsbad, NM 88220 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wang, YF (reprint author), Sandia Natl Labs, 4100 Natl Pks Highway, Carlsbad, NM 88220 USA. NR 22 TC 15 Z9 17 U1 2 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD FEB PY 2001 VL 47 IS 2-4 BP 297 EP 309 DI 10.1016/S0169-7722(00)00158-3 PG 13 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 399ZP UT WOS:000166844400018 PM 11288584 ER PT J AU Yeh, GT Siegel, MD Li, MH AF Yeh, GT Siegel, MD Li, MH TI Numerical modeling of coupled variably saturated fluid flow and reactive transport with fast and slow chemical reactions SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article; Proceedings Paper CT 7th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere (MIGRATION 99) CY SEP 26-OCT 01, 1999 CL LAKE TAHOE, CALIFORNIA SP Lawrence Livemore Natl Lab DE reactive transport; numerical models; geochemistry; groundwater; remediation AB The couplings among chemical reaction rates, advective and diffusive transport in fractured media or soils, and changes in hydraulic properties due to precipitation and dissolution within fractures and in rock matrix are important for both nuclear waste disposal and remediation of contaminated sites. This paper describes the development and application of LEHGC2.0, a mechanistically based numerical model for simulation of coupled fluid flow and reactive chemical transport, including both fast and slow reactions in variably saturated media. Theoretical bases and numerical implementations are summarized, and two example problems are demonstrated. The first example deals with the effect of precipitation/dissolution on fluid flow and matrix diffusion in a two-dimensional fractured media. Because of the precipitation and decreased diffusion of solute from the fracture into the matrix, retardation in the fractured medium is not as large as the case wherein interactions between chemical reactions and transport are not considered. The second example focuses on a complicated but realistic advective-dispersive-reactive transport problem. This example exemplifies the need for innovative numerical algorithms to solve problems involving stiff geochemical reactions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Penn State Univ, Dept Civil & Environm Engn, University Pk, PA 16802 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Yeh, GT (reprint author), Penn State Univ, Dept Civil & Environm Engn, 212 Sackett Bldg, University Pk, PA 16802 USA. NR 6 TC 16 Z9 18 U1 3 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD FEB PY 2001 VL 47 IS 2-4 BP 379 EP 390 DI 10.1016/S0169-7722(00)00164-9 PG 12 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 399ZP UT WOS:000166844400024 PM 11288590 ER PT J AU Jorgensen, AM Henderson, MG Roelof, EC Reeves, GD Spence, HE AF Jorgensen, AM Henderson, MG Roelof, EC Reeves, GD Spence, HE TI Charge exchange contribution to the decay of the ring current, measured by energetic neutral atoms (ENAs) SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FEBRUARY 1986; DST INDEX; STORM; POLAR; ASSOCIATION; IMAGES; LOSSES; PHASE AB In this paper we calculate the contribution of charge exchange to the decay of the ring current. Past works have suggested that charge exchange of ring current protons is primarily responsible for the decay of the ring current during the late recovery phase, but there is still much debate about the fast decay of the early recovery phase. We use energetic neutral atom (ENA) measurements from Polar to calculate the total ENA energy escape. To get the total ENA escape we apply a forward modeling technique, and to estimate the total ring current energy escape we use the Dessler-Parker-Sckopke relationship. We find that during the late recovery phase of the March 10, 1998 storm ENAs with energies greater than 17.5 keV can account for 75% of the estimated energy loss from the ring current. During the fast recovery the measured ENAs can only account for a small portion of the total energy loss. We also find that the lifetime of the trapped ions is significantly shorter during the fast recovery phase than during the late recovery phase, suggesting that different processes are operating during the two phases. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. RP Jorgensen, AM (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop D-466,SM-30,Bikini Atoll Rd, Los Alamos, NM 87545 USA. RI Spence, Harlan/A-1942-2011; Reeves, Geoffrey/E-8101-2011; Henderson, Michael/A-3948-2011 OI Reeves, Geoffrey/0000-0002-7985-8098; Henderson, Michael/0000-0003-4975-9029 NR 30 TC 15 Z9 15 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 FEB 1 PY 2001 VL 106 IS A2 BP 1931 EP 1937 DI 10.1029/2000JA000124 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 395HV UT WOS:000166575700016 ER PT J AU Dowding, KJ Blackwell, BF AF Dowding, KJ Blackwell, BF TI Sensitivity analysis for nonlinear heat conduction SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE conduction; parameter estimation; heat transfer ID THERMAL-PROPERTIES; FINITE-ELEMENTS; UNCERTAINTIES; COMPOSITE; DESIGN AB Parameters in the heat conduction equation are frequently modeled as temperature dependent. Thermal conductivity, volumetric heat capacity, convection coefficients, emissivity, and volumetric source terms are parameters that may depend on temperature. Many applications, such as parameter estimation, optimal experimental design, optimization, and uncertainty analysis, require sensitivity to the parameters describing temperature-dependent properties. A general procedure to compute the sensitivity of the temperature field to model parameters for nonlinear heat conduction is studied. Parameters are modeled as arbitrary functions of temperature. Sensitivity equations are implemented in an unstructured grid, element-based numerical solver. The objectives of this study are to describe the methodology to derive sensitivity equations for the temperature-dependent parameters and present demonstration calculations. In addition to a verification problem, the design of an experiment to estimate temperature variable thermal properties is discussed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dowding, KJ (reprint author), Sandia Natl Labs, POB 5800,Mail Stop 0828, Albuquerque, NM 87185 USA. NR 22 TC 18 Z9 18 U1 0 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD FEB PY 2001 VL 123 IS 1 BP 1 EP 10 DI 10.1115/1.1332780 PG 10 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 409DE UT WOS:000167368600001 ER PT J AU Aviles-Ramos, C Haji-Sheikh, A Beck, JV Dowding, KJ AF Aviles-Ramos, C Haji-Sheikh, A Beck, JV Dowding, KJ TI Estimation of thermophysical properties by the spectral method - Development and evaluation SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE conductive; heat transfer; inverse; properties; thermophysical ID CARBON-CARBON COMPOSITE; THERMAL-PROPERTIES AB This paper reports the evaluation of a spectral technique for estimating thermophysical properties. It demonstrates that one can construct a virtual quasi-steady periodic experiment from a limited but properly selected set of transient non-periodic data. In the spectral domain, the phase angles of the responses at different locations relative to a periodic input signal depend on the thermophysical properties. For the purpose of this evaluation, the transient temperature responses to a surface heat flux input are analytically obtained at pre-selected sensor locations. The transient data are converted to periodic data, phase angles are computed, and thermophysical properties are estimated. All deviations from known property values due to numerical errors are reported. C1 Univ Texas, Dept Mech & Aerosp Engn, Arlington, TX 76019 USA. Michigan State Univ, Dept Mech Engn, E Lansing, MI 48824 USA. Sandia Natl Labs, Thermal Sci Dept, Albuquerque, NM 87185 USA. RP Aviles-Ramos, C (reprint author), Univ Texas, Dept Mech & Aerosp Engn, Arlington, TX 76019 USA. NR 13 TC 8 Z9 8 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD FEB PY 2001 VL 123 IS 1 BP 24 EP 30 DI 10.1115/1.1336507 PG 7 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 409DE UT WOS:000167368600003 ER PT J AU Arkani-Hamed, N Murayama, H Nomura, Y Kaplan, DE AF Arkani-Hamed, N Murayama, H Nomura, Y Kaplan, DE TI Viable ultraviolet-insensitive supersymmetry breaking SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE anomalies in field and string theories; supersymmetry breaking; beyond standard model; supersymmetric standard model ID EXTRA DIMENSIONS; GAUGE-THEORIES; ART.; MODELS; TEVATRON; FLAVOR; MASSES; TERMS AB It is known that one can add D-term contributions for U(1)(Y) and U(1)(B-L) to the anomaly-mediated supersymmetry breaking to make the superparticle spectrum phenomenologically viable. We point out that this can be done without spoiling its important virtue, namely the ultraviolet insensitivity. This framework can be derived from supersymmetry breaking and U(1)(B-L) breaking on hidden brane(s). C1 Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Ctr Theoret Phys, Berkeley, CA 94720 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Argonne Natl Lab, High Energy Phys Div, Argonne, IL 60439 USA. RP Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. EM arkani@thwk1.lbl.gov; murayama@lbl.gov; yasunori@thsrv.lbl.gov; dkaplan@theory.uchicago.edu RI Murayama, Hitoshi/A-4286-2011 NR 41 TC 68 Z9 68 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD FEB PY 2001 IS 2 AR 041 PG 17 WC Physics, Particles & Fields SC Physics GA 423EQ UT WOS:000168162800041 ER PT J AU Bernevig, BA Susskind, L Toumbas, N Brodie, JH AF Bernevig, BA Susskind, L Toumbas, N Brodie, JH TI How Bob Laughlin tamed the giant graviton from Taub-NUT space SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE superstrings and heterotic strings; D-branes; non-commutative geometry ID GAUGE-THEORY; DYNAMICS; FLUID AB In this paper we show how two dimensional electron systems can be modeled by strings interacting with D-branes. The dualities of string theory allow several descriptions of the system. These include descriptions in terms of solitons in the near horizon D6-brane theory, non-commutative gauge theory on a D2-brane, the Matrix Theory of D0-branes and finally as a giant graviton in M-theory. The soliton can be described as a D2-brane with an incompressible fluid of D0-branes and charged string-ends moving on it. Including an NS5-brane in the system allows for the existence of an edge with the characteristic massless chiral edge states of the Quantum Hall system. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Stanford Univ, Dept Phys, Stanford, CA 94305 USA. EM bernevig@stanford.edu; susskind@sewerrat.stanford.edu; ntoumbas@stanford.edu; brodie@SLAC.Stanford.EDU NR 24 TC 8 Z9 8 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD FEB PY 2001 IS 2 AR 003 PG 26 WC Physics, Particles & Fields SC Physics GA 423EQ UT WOS:000168162800003 ER PT J AU Sterman, G Vogelsang, W AF Sterman, G Vogelsang, W TI Threshold resummation and rapidity dependence SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE QCD; asymptotic freedom; Parton model; hadronic colliders ID PROMPT PHOTON PRODUCTION; QCD HARD SCATTERING; CROSS-SECTIONS; PARTON DISTRIBUTIONS; HADRONIC COLLISIONS; LEADING ORDER; SINGLE AB We study the effects of threshold resummation on the rapidity dependence of single-particle-inclusive cross sections, using the prompt photon cross section as an example. We make use of the full resummation formula at next-to-leading logarithmic accuracy and develop a new technique for treating rapidity in resummation. We compare our phenomenological results with those of previous studies and discuss the close relation between resummation formalisms in the literature. C1 SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. EM sterman@quark.phy.bnl.gov; vogelsan@quark.phy.bnl.gov NR 37 TC 46 Z9 46 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 FEB PY 2001 IS 2 AR 016 PG 25 WC Physics, Particles & Fields SC Physics GA 423EQ UT WOS:000168162800016 ER PT J AU Slater, AG Schlosser, CA Desborough, CE Pitman, AJ Henderson-Sellers, A Robock, A Vinnikov, KY Mitchell, K Boone, A Braden, H Chen, F Cox, PM de Rosnay, P Dickinson, RE Dai, YJ Duan, Q Entin, J Etchevers, P Gedney, N Gusev, YM Habets, F Kim, J Koren, V Kowalczyk, EA Nasonova, ON Noilhan, J Schaake, S Shmakin, AB Smirnova, TG Verseghy, D Wetzel, P Yue, X Yang, ZL Zeng, Q AF Slater, AG Schlosser, CA Desborough, CE Pitman, AJ Henderson-Sellers, A Robock, A Vinnikov, KY Mitchell, K Boone, A Braden, H Chen, F Cox, PM de Rosnay, P Dickinson, RE Dai, YJ Duan, Q Entin, J Etchevers, P Gedney, N Gusev, YM Habets, F Kim, J Koren, V Kowalczyk, EA Nasonova, ON Noilhan, J Schaake, S Shmakin, AB Smirnova, TG Verseghy, D Wetzel, P Yue, X Yang, ZL Zeng, Q TI The representation of snow in land surface schemes: Results from PILPS 2(d) SO JOURNAL OF HYDROMETEOROLOGY LA English DT Review ID GENERAL-CIRCULATION MODELS; NORTHERN-HEMISPHERE CLIMATE; MIDLATITUDE SOIL-MOISTURE; BOUNDARY-LAYER; PARAMETERIZATION SCHEME; GLOBAL CLIMATE; ATMOSPHERIC MODELS; LOCAL ADVECTION; SPECTRAL ALBEDO; SENSIBLE HEAT AB Twenty-one land surface schemes (LSSs) performed simulations forced by 18 yr of observed meteorological data from a grassland catchment at Valdai. Russia, as part of the Project for the Intercomparison of Land-Surface Parameterization Schemes (PILPS) Phase 2(d). In this paper the authors examine the simulation of snow. In comparison with observations, the models are able to capture the broad features of the snow regime on both an intra- and interannual basis. However, weaknesses in the simulations exist, and early season ablation events are a significant source of model scatter. Over the 18-yr simulation, systematic differences between the models' snow simulations are evident and reveal specific aspects of snow model parameterization and design as being responsible. Vapor exchange at the snow surface varies widely among the models, ranging from a large net loss to a small net source for the snow season. Snow albedo, fractional snow cover, and their interplay have a large effect on energy available for ablation, with differences among models most evident at low snow depths. The incorporation of the snowpack within an LSS structure affects the method by which snow accesses, as well as utilizes, available energy for ablation. The sensitivity of some models to longwave radiation, the dominant winter radiative flux, is partly due to a stability-induced feedback and the differing abilities of models to exchange turbulent energy with the atmosphere. Results presented in this paper suggest where weaknesses in macroscale snow modeling lie and where both theoretical and observational work should he focused to address these weaknesses. C1 Univ Colorado, CIRES, Boulder, CO 80309 USA. Ctr Ocean Land Atmosphere Studies, Calverton, MD USA. Macquarie Univ, Dept Phys Geog, Sydney, NSW 2109, Australia. Australian Nucl Sci & Technol Org, Sydney, NSW, Australia. Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08903 USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. NOAA, NCEP, Environm Modeling Ctr, Camp Springs, MD USA. Meteo France, CNRM, Toulouse, France. German Meteorol Serv, Braunschweig, Germany. Hadley Ctr Climate Predict & Res, Bracknell, Berks, England. CNRS, Meteorol Dynam Lab, Paris, France. Univ Arizona, Inst Atmospher Phys, Tucson, AZ 85721 USA. Chinese Acad Sci, Inst Atmospher Phys, Beijing, Peoples R China. NOAA, Off Hydrol, Silver Spring, MD USA. Univ Reading, Dept Meteorol, Reading, Berks, England. Russian Acad Sci, Inst Water Problems, Moscow, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. CSIRO, Div Atmospher Res, Aspendale, Vic 3195, Australia. Russian Acad Sci, Inst Geog, Moscow, Russia. Meteorol Serv Canada, Climat Res Branch, Downsview, ON, Canada. NASA, Goddard Space Flight Ctr, Mesoscale Dynam & Precipitat Branch, Greenbelt, MD 20771 USA. Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90024 USA. RP Slater, AG (reprint author), Univ Colorado, CIRES, Campus Box 216, Boulder, CO 80309 USA. EM aslater@cires.colorado.edu RI Cox, Peter/B-3299-2012; Dai, Yongjiu/D-6261-2014; Slater, Andrew/B-4666-2008; Vinnikov, Konstantin/F-9348-2010; Dai, Yongjiu/D-1070-2010; Yang, Zong-Liang/B-4916-2011; Pitman, Andrew/A-7353-2011; Henderson-Sellers, Ann/H-5323-2011; Chen, Fei/B-1747-2009; de Rosnay, Patricia/M-8203-2013; Nasonova, Olga/B-6093-2014; Duan, Qingyun/C-7652-2011; gusev, yugeniy/G-4711-2014; Smirnova, Tatiana/D-3350-2015; Robock, Alan/B-6385-2016 OI Dai, Yongjiu/0000-0002-3588-6644; SLATER, ANDREW/0000-0002-4009-4844; Slater, Andrew/0000-0003-0480-8560; Habets, Florence/0000-0003-1950-0921; Pitman, Andrew/0000-0003-0604-3274; de Rosnay, Patricia/0000-0002-7374-3820; Duan, Qingyun/0000-0001-9955-1512; gusev, yugeniy/0000-0003-3886-2143; NR 108 TC 174 Z9 179 U1 3 U2 30 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1525-755X EI 1525-7541 J9 J HYDROMETEOROL JI J. Hydrometeorol. PD FEB PY 2001 VL 2 IS 1 BP 7 EP 25 DI 10.1175/1525-7541(2001)002<0007:TROSIL>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 407BD UT WOS:000167250800003 ER PT J AU Lorenzana, HE Lipp, MJ Evans, WJ Hemmi, N AF Lorenzana, HE Lipp, MJ Evans, WJ Hemmi, N TI Vibrational spectroscopy at high pressures in CF4: Implications to the phase diagram SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article; Proceedings Paper CT 3rd International Conference on Cryocrystals and Quantum Crystals (CC 2000) CY JUL 28-AUG 04, 2000 CL SZKLARSKA, POLAND ID CARBON TETRAFLUORIDE; CRYSTAL-STRUCTURE; DIFFRACTION; SPECTRA; LIQUID AB The molecular analogue of methane. CF4 is the most fundamental saturated perfluorocarbon, exhibiting complex optical behavior that is highly unusual for such a simple molecular system. We present Raman measurements in solid CF4 over a wide range in pressure from 1.6 to over 30 GPa at room temperature. The Raman spectra exhibit polarization-dependent intensity variations and history-dependent absence or presence of high pressure modes. Our results compellingly demonstrate that previously identified phase transitions in CF4 based on Raman signatures need to be reconsidered. Though our data suggest possible new high-pressure transitions, we do not identify new phases because of spectral complexity. Finally, we used the measured longitudinal and transverse optical mode splitting to estimate the dipole moment derivative at high pressures and find it close to that of gaseous CF4. C1 Univ Calif Lawrence Livermore Natl Lab, Phys & Adv Technol Directorate, Livermore, CA 94551 USA. RP Lorenzana, HE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Phys & Adv Technol Directorate, Livermore, CA 94551 USA. NR 24 TC 4 Z9 4 U1 0 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD FEB PY 2001 VL 122 IS 3-4 BP 279 EP 290 DI 10.1023/A:1004892616018 PG 12 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 426JF UT WOS:000168345500020 ER PT J AU Crew, DC Lewis, LH Panchanathan, V AF Crew, DC Lewis, LH Panchanathan, V TI The effect of evolving grain shape and alignment on the coercivity in thermomechanically deformed Nd-13.9(Fe-0.92 Co-0.08)(80.3) B5.3Ga0.5 permanent magnets SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE coercivity; crystallographic alignment; permanent magnet; demagnetization ID ND-FE-B; MICROMAGNETIC ANALYSIS; MECHANISMS; DEPENDENCE; FIELDS AB A series of samples of nominally identical composition have been melt-quenched and thermomechanically deformed to varying degrees, resulting in a variation in crystallographic alignment. The effect of the alignment on the coercivity has been studied using measurements of the temperature dependence of coercivity. The analysis was performed using a well-known phenomenological model which relates the coercivity to the anisotropy field, through a parameter alpha, and the saturation magnetization, through an effective demagnetization coefficient N-eff. It was discovered that the trends in alpha and N-eff as a function of crystallographic grain alignment are the opposite to what is expected and measured previously in analogous sintered samples of varying crystallographic alignment. An explanation for this behavior is proposed in which the evolving grain shape and grain boundary topography caused by deformation becomes the controlling factor in the coercivity rather than the crystallographic alignment of the grains. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Energy Sci & Technol Dept, Upton, NY 11973 USA. Magnequench Int Inc, Anderson, IN USA. RP Lewis, LH (reprint author), Brookhaven Natl Lab, Energy Sci & Technol Dept, Bldg 480, Upton, NY 11973 USA. NR 18 TC 4 Z9 4 U1 1 U2 8 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 FEB PY 2001 VL 223 IS 3 BP 261 EP 266 DI 10.1016/S0304-8853(00)01272-5 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 399NA UT WOS:000166818200009 ER PT J AU Vavassori, P Grimsditch, M Fullerton, EE AF Vavassori, P Grimsditch, M Fullerton, EE TI Biquadratic exchange coupling in an unequal Fe/Cr/Fe(100) trilayer SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE Fe/Cr superlattices; magnetic; biquadratic; bilinear; brillouin scattering; and MOKE ID BRILLOUIN LIGHT-SCATTERING; LAYERED MAGNETIC-STRUCTURES; FE/CR(001) SUPERLATTICES; MECHANISM; CR; MULTILAYERS; MAGNETORESISTANCE; DEPENDENCE; FILMS AB we have investigated the magnetic properties of a (100)-oriented unequal trilayer, Fe(45 Angstrom)/Cr(30 Angstrom)/Fe(15 Angstrom), by means of Brillouin light scattering and magnetization measurements. The experimental results show that this sample highlights the effect of biquadratic coupling which aligns the magnetization of the Fe layers at 90 degrees to each other. We extracted the bilinear and biquadratic coupling strengths by fitting the experimental results with a theory that treats the static and dynamic responses on an equal footing. Our results confirm that the model describes both the static and dynamic properties even when the magnetization of the layers is aligned at 90 degrees. The coupling strengths, and their temperature dependence, are discussed and compared with other results reported in the literature, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci 223, Argonne, IL 60439 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. RP Grimsditch, M (reprint author), Argonne Natl Lab, Div Mat Sci 223, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Fullerton, Eric/H-8445-2013; Vavassori, Paolo/B-4299-2014 OI Fullerton, Eric/0000-0002-4725-9509; Vavassori, Paolo/0000-0002-4735-6640 NR 34 TC 7 Z9 7 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD FEB PY 2001 VL 223 IS 3 BP 284 EP 292 DI 10.1016/S0304-8853(00)01334-2 PG 9 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 399NA UT WOS:000166818200013 ER PT J AU Lazar, L Jiang, JS Felcher, GP Inomata, A Bader, SD AF Lazar, L Jiang, JS Felcher, GP Inomata, A Bader, SD TI Oscillatory exchange bias in Fe/Cr double superlattices SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE exchange bias; superlattice; interlayer coupling; exchange coupling; epitaxy ID MODEL; BILAYERS; FILMS; FERROMAGNET; INTERFACES; ANISOTROPY AB In the [Fe/Cr](AF)/Cr(x)/[Fe/Cr](F) double superlattices consisting of a ferromagnetic Fe/Cr superlattice on top of an antiferromagnetic Fe/Cr superlattice, the exchange coupling between the superlattices is determined by the thicknesses (x of the Cr spacer layer. The oscillating behavior of the exchange bias field of a series of (211)-oriented Fe/Cr double superlattices was determined by superconducting quantum interference device (SQUID) and magneto-optic Kerr effect (MOKE) measurements. For x > 13 Angstrom a negative strongly oscillating character of the exchange bias was observed. At very thick x the exchange bias vanishes. The most immediate result is the fact that the exchange bias field is always negative, regardless of the sign of the coupling between the ferromagnetic and the antiferromagnetic superlattices. The detailed dependence of the exchange bias field as a function of the intersuperlattice thickness of Cr is explained in terms of the interaction between the two superlattices in collinear configuration. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Ruhr Univ Bochum, Inst Expt Phys Festkorperphys, D-44780 Bochum, Germany. RP Jiang, JS (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM jiang@anl.gov RI Bader, Samuel/A-2995-2013 NR 17 TC 11 Z9 11 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD FEB PY 2001 VL 223 IS 3 BP 299 EP 303 DI 10.1016/S0304-8853(00)01366-4 PG 5 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 399NA UT WOS:000166818200015 ER PT J AU Quirke, JME Van Berkel, GJ AF Quirke, JME Van Berkel, GJ TI Electrospray tandem mass spectrometric study of ferrocene carbamate ester derivatives of saturated primary, secondary and tertiary alcohols SO JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electrospray mass spectrometry; alcohols; ferrocene carbamate esters; derivatization; tandem mass spectrometry; fragmentation mechanisms ID 4-AMINONAPHTHALENESULPHONIC ACID; IONIZATION; DERIVATIZATION; OLIGOSACCHARIDES; METABOLITES; PEPTIDES; PRINCIPLES; REAGENTS; PHENOLS AB The fragmentation pathways and mechanisms for 27 ferrocene carbamate esters of saturated alkyl primary, secondary and tertiary alcohols were investigated using energy-resolved electrospray tandem mass spectrometry (ES-MS/MS). The mechanisms that control the formation and abundance of the three product ions common to all the derivatives, which appear at m/z 201., 227 and 245, were elucidated. Plotting the relative abundances of the three product ions versus a range of center-of-mass collision energies provided a graphical representation of the behavior of the fragmentation process that was directly comparable from compound to compound. As a result, it was possible to compare product ion spectra of the different derivatives to distinguish among different alcohol structural types. Straight-chain primary alcohols were easily distinguished from tertiary alcohols. Both of these structural types, including positional isomers, produced product ion spectra that were distinct from those of beta -branched primary alcohols, or acyclic secondary alcohols or cyclic secondary alcohols. The latter three alcohol types display similar product ion spectra and therefore cannot be distinguished from one another on the basis of these spectra alone. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Florida Int Univ, Dept Chem, Miami, FL 33199 USA. RP Van Berkel, GJ (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 29 TC 21 Z9 21 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1076-5174 J9 J MASS SPECTROM JI J. Mass Spectrom. PD FEB PY 2001 VL 36 IS 2 BP 179 EP 187 DI 10.1002/jms.119 PG 9 WC Biophysics; Chemistry, Organic; Spectroscopy SC Biophysics; Chemistry; Spectroscopy GA 406AG UT WOS:000167192300008 PM 11288200 ER PT J AU Kertesz, V Van Berkel, GJ AF Kertesz, V Van Berkel, GJ TI Minimizing analyte electrolysis in an electrospray emitter SO JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electrospray mass spectrometry; electrolysis; oxidation; stainless-steel emitter; platinum emitter; fused-silica emitter ID IONIZATION MASS-SPECTROMETRY; RADICAL CATIONS; REDOX REACTIONS; COUPLED ONLINE; GAS-PHASE; CELL; METALLOCENES; ANILINE AB The electrospray (ES) ion source is a controlled-current electrolytic now cell. Electrolytic reactions in the ES emitter capillary are continually ongoing to sustain the production of charged droplets and ultimately gas-phase ions from this device. Under certain circumstances, the analytes under study may be directly involved in these electrolytic processes. It is demonstrated that a simple means to minimize analyte electrolysis is to exchange the normal metal emitter capillary of commercial ES sources with one made of fused silica. This change is shown to provide an ES mass spectrometric system of similar performance in terms of gas-phase ion signal generated for non-electroactive analytes and also assures minimal oxidation of electroactive analytes even at low (2.0 mul min(-1)) solution flow-rates and high (millimolar) solution electrolyte concentrations. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37381 USA. RP Van Berkel, GJ (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37381 USA. RI Kertesz, Vilmos/M-8357-2016 OI Kertesz, Vilmos/0000-0003-0186-5797 NR 21 TC 40 Z9 40 U1 1 U2 8 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1076-5174 J9 J MASS SPECTROM JI J. Mass Spectrom. PD FEB PY 2001 VL 36 IS 2 BP 204 EP 210 DI 10.1002/jms.122 PG 7 WC Biophysics; Chemistry, Organic; Spectroscopy SC Biophysics; Chemistry; Spectroscopy GA 406AG UT WOS:000167192300011 PM 11288203 ER PT J AU Luo, JS Liu, GK AF Luo, JS Liu, GK TI Microscopic effects of self-radiation damage in Cm-244-doped LuPO4 crystals SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID ALPHA-DECAY DAMAGE; INDUCED AMORPHIZATION; NUCLEAR WASTE; ZIRCON; MONAZITE; CAZRTI2O7; CHEMISTRY; MINERALS; CERAMICS; TEM AB Microscopic effects of self-radiation damage in Cm-244-doped LuPO4 crystals were examined with transmission electron microscopy. These LuPO4 crystals had been doped with 1 wt% Cm-244 and exposed to a radiation dose as high as 5 x 10(16) alpha -decay events/mg over 18 years. The microscopic analysis revealed dense arrays of individual defect clusters and numerous bubbles. Whereas, the defect clusters may be interpreted as residuals of alpha-recoil tracks, the bubbles likely resulted from the alpha -particles generated during the decay events. The bubbles were found to coalesce under electron beam irradiation. Despite the high accumulated dose over the 18 years, the samples exhibited sharp diffraction patterns and periodic lattice spacings. This finding indicated that the samples remained largely crystalline and that the radiation-induced lattice damage was recovered at a rate comparable to that of damage production. This high recoverability is discussed with respect of various annealing processes that may have occurred in the samples. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Luo, JS (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 36 TC 3 Z9 3 U1 0 U2 9 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 FEB PY 2001 VL 16 IS 2 BP 366 EP 372 DI 10.1557/JMR.2001.0056 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 398UY UT WOS:000166775900009 ER PT J AU Zurbuchen, MA Lettieri, J Jia, Y Schlom, DG Streiffer, SK Hawley, ME AF Zurbuchen, MA Lettieri, J Jia, Y Schlom, DG Streiffer, SK Hawley, ME TI Transmission electron microscopy study of (103)-oriented epitaxial SrBi2Nb2O9 films grown on (111) SrTiO3 and (111) SrRuO3/(111) SrTiO3 SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID FERROELECTRIC NONVOLATILE MEMORY; SINGLE-CRYSTAL; THIN-FILMS; BISMUTH TITANATE; SUBSTRATE; INTERFACE; SURFACE AB Portions of the same epitaxial (103)-oriented SrBi2Nb2O9 film grown on (111) SrTiO3 for which we recently reported the highest remanent polarization (P-r) ever achieved in SrBi2Nb2O9 (or SrBi2Ta2O9) films, i.e., P-r = 15.7 muC/cm(2), have been characterized microstructurally by plan-view and cross-sectional transmission electron microscopy (TEM) along three orthogonal viewing directions. SrBi2Nb2O9 grows with its c axis tilted 57 degrees from the substrate surface normal in a three-fold twin structure about the substrate [111], with the growth twins' c axes nominally aligned with the three [100] SrTiO3 directions. (103) SrBi2Nb2O9 films with and without an underlying epitaxial SrRuO3 bottom electrode have been studied. Dark-field TEM imaging over a 12 mum(2) area shows no evidence of second phases (crystalline or amorphous). A high density of out-of-phase boundaries exists in the films. C1 Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16803 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Zurbuchen, MA (reprint author), Univ Augsburg, Inst Phys, D-86159 Augsburg, Germany. RI Streiffer, Stephen/A-1756-2009; Zurbuchen, Mark/H-1664-2012; Schlom, Darrell/J-2412-2013 OI Zurbuchen, Mark/0000-0002-8947-6309; Schlom, Darrell/0000-0003-2493-6113 NR 29 TC 13 Z9 13 U1 0 U2 10 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD FEB PY 2001 VL 16 IS 2 BP 489 EP 502 DI 10.1557/JMR.2001.0072 PG 14 WC Materials Science, Multidisciplinary SC Materials Science GA 398UY UT WOS:000166775900025 ER PT J AU Koc, R Glatzmaier, G Sibold, J AF Koc, R Glatzmaier, G Sibold, J TI beta-SiC production by reacting silica gel with hydrocarbon gas SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB A novel synthesis process, developed for producing high purity, submicron, non-agglomerated and low cost beta -SiC powders. The process is based on carbothermal reduction reaction of a novel coated precursor. The precursor is derived from a silica gel and a hydrocarbon gas and provides high contact area between reactants. This yields a better distribution of carbon within the silica gel and results in a more complete reaction and a purer product. The powders produced in this process have a low oxygen content (less than 0.8 wt.%), very fine particle size (0.1-0.3 mum), narrow particle size distribution, non-agglomerated and are low cost. The sintering tests demonstrated that these powders can be pressureless-sintered to near theoretical density at about 2100 degreesC in an inert atmosphere. No decarburization and no acid purification process was required before sintering. (C) 2001 Kluwer Academic Publishers. C1 So Illinois Univ, Dept Mech Engn & Energy Proc, Carbondale, IL 62901 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. TDA Res Inc, Wheat Ridge, CO 80033 USA. RP Koc, R (reprint author), So Illinois Univ, Dept Mech Engn & Energy Proc, Carbondale, IL 62901 USA. NR 4 TC 25 Z9 27 U1 0 U2 2 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 FEB PY 2001 VL 36 IS 4 BP 995 EP 999 DI 10.1023/A:1004888209926 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 400EZ UT WOS:000166860400031 ER PT J AU Cairney, JM Munroe, PR Sordelet, DJ AF Cairney, JM Munroe, PR Sordelet, DJ TI Microstructural analysis of a FeAl/quasicrystal-based composite prepared using a focused ion beam miller SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article; Proceedings Paper CT 5th International Conference on Microscopy of Composite Materials CY APR 03-04, 2000 CL ST JOHNS COLL, OXFORD, ENGLAND SP Oxford Ctr Adv Mat & Composites, Royal Microscop Soc HO ST JOHNS COLL DE composite; FeAl; FIB; intermetallic; quasicrystal; TEM ID SPECIMEN PREPARATION; FE; SYSTEM; PHASE; AL; EQUILIBRIA; BEHAVIOR; ALLOYS AB A composite consisting of a brittle multiphase matrix containing bath an Al-based quasicrystalline phase (psi) and an ordered body centred cubic phase (beta) and a relatively ductile ordered body centred cubic intermetallic FeAl phase has been developed as an abrasive wear-resistant coating material. It is applied as a 500 mum thick layer onto stainless steel substrates through plasma spray processing. The microstructure of such materials can be readily examined by optical and scanning electron microscopy, but the inherent difficulty of preparing transmission electron microscope (TEM) samples has inhibited higher resolution studies. However, the relatively recent development of the focused ion beam (FIB) miller as a tool in materials science provides a method ideal for the preparation of TEM specimens of these materials. In this study a coating consisting of a mixture of an Al-Cu-Fe based quasicrystal and FeAl+Cr was deposited on to a 304 stainless steel substrate, TEM specimens were prepared using a FIB and subjected to detailed microstructural characterization. The structure consisted of elongated bands of a FeAl phase about 100 nm in width and several micrometres in length, which enclosed more equiaxed regions about 1 mum in diameter that consisted of fine mixtures of quasicrystal and two Al-Fe-Cu phases isostructurally related to FeAl. C1 Univ New S Wales, Sydney, NSW 2052, Australia. Iowa State Univ, Ames Lab, Met & Ceram Program, Ames, IA 50011 USA. RP Munroe, PR (reprint author), Univ New S Wales, Sydney, NSW 2052, Australia. RI Cairney, Julie/J-7931-2012; Munroe, Paul/I-9313-2016; OI Munroe, Paul/0000-0002-5091-2513; Cairney, Julie/0000-0003-4564-2675 NR 23 TC 14 Z9 14 U1 0 U2 5 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD FEB PY 2001 VL 201 BP 201 EP 211 DI 10.1046/j.1365-2818.2001.00764.x PN 2 PG 11 WC Microscopy SC Microscopy GA 414VG UT WOS:000167686400011 ER PT J AU Butts, DA Rokhsar, DS AF Butts, DA Rokhsar, DS TI The information content of spontaneous retinal waves SO JOURNAL OF NEUROSCIENCE LA English DT Article DE information theory; activity dependent; development; retinal waves; retinogeniculate; refinement; retinotopy ID VISUAL-SYSTEM DEVELOPMENT; RETINOTECTAL PROJECTION; SYNAPTIC TRANSMISSION; MAMMALIAN RETINA; IMPULSE ACTIVITY; GANGLION-CELLS; TETRODOTOXIN; COMPETITION; REFINEMENT; GOLDFISH AB Spontaneous neural activity that is present in the mammalian retina before the onset of vision is required for the refinement of retinotopy in the lateral geniculate nucleus and superior colliculus. This paper explores the information content of this retinal activity, with the goal of determining constraints on the nature of the developmental mechanisms that use it. Through information-theoretic analysis of multielectrode and calcium-imaging experiments, we show that the spontaneous retinal activity present early in development provides information about the relative positions of retinal ganglion cells and can, in principle, be used at retinogeniculate and retinocollicular synapses to refine retinotopy. Remarkably, we find that most retinotopic information provided by retinal waves exists on relatively coarse time scales, suggesting that developmental mechanisms must be sensitive to timing differences from 100 msec up to 2 sec to make optimal use of it. In fact, a simple Hebbian-type learning rule with a correlation window on the order of seconds is able to extract the bulk of the available information. These findings are consistent with bursts of action potentials (rather than single spikes) being the unit of information used during development and suggest new experimental approaches for studying developmental plasticity of the retinogeniculate and retinocollicular synapses. More generally, these results demonstrate how the properties of neuronal systems can be inferred from the statistics of their input. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Butts, DA (reprint author), Harvard Univ, Sch Med, Dept Neurobiol, Goldenson 405,220 Longwood Ave, Boston, MA 02115 USA. RI Butts, Daniel/B-8346-2008 OI Butts, Daniel/0000-0002-0158-5317 NR 42 TC 45 Z9 45 U1 1 U2 2 PU SOC NEUROSCIENCE PI WASHINGTON PA 11 DUPONT CIRCLE, NW, STE 500, WASHINGTON, DC 20036 USA SN 0270-6474 J9 J NEUROSCI JI J. Neurosci. PD FEB 1 PY 2001 VL 21 IS 3 BP 961 EP 973 PG 13 WC Neurosciences SC Neurosciences & Neurology GA 398WF UT WOS:000166778900026 PM 11157082 ER PT J AU Magruder, RH Weller, RA Weeks, RA Wehrmeyer, J Zuhr, RA Hensley, DK AF Magruder, RH Weller, RA Weeks, RA Wehrmeyer, J Zuhr, RA Hensley, DK TI Effects of ArF excimer irradiation on single energy and multi energy Ge ion implanted silica SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 3rd Symposium on SiO2 and Advanced Dielectrics CY JUN 19-21, 2000 CL FUVEAU, FRANCE SP European Commiss Human Potent Programme High Level Sci Conf, Reg Provence Alpes Cote Azur, Univ Provence, Aerosp Matra, Univ Milano Bicocca, Lab Mat Micro-Electron Provence, Univ Milano-Bicocca, Dipartiment Sci Mat, Univ Aquila, Dipartiment Fis, CEA & DAM, Lab Pys Mat, Assoc Europhys Symp, STUniversity ID FUSED-SILICA; OPTICAL FIBERS; WAVE-GUIDES; INDEX CHANGES; HEAVY-ION; PHOTOSENSITIVITY; SIO2; GLASSES; CENTERS; DEFECTS AB Some of the effects of ArF excimer irradiation on the optical bands produced by single energy (4 MeV) and multi energy (highest energy 4 MeV) Ge implantations in silica (Type III) have been determined. Ge ions were implanted at 4 MeV with nominal doses of 1.25, 2.5 and 5.0 x 10(15) ions/cm(2). A second series of samples was made using implant energies ranging from 4 to 0.7 MeV. The doses at each energy were varied to maintain an approximate constant implant species concentration with the total number of ions implanted being 10 x 10(15) and 5 x 10(15) cm(-2) for concentrations of 0.042 and 0.021 at,%, respectively. The optical absorption was measured from 2.8 to 6.5 eV. The absorption of samples was then measured after 6.4 eV ArF excimer radiation with a fluence of 44 mJ/cm(2) per pulse for pulse totals of 3, 11 and 31. We fit the observed spectra for the as-implanted samples and the samples after each ArF exposure to the minimum number of bands attributed to intrinsic states in SiO2 required to fit the data within +/-2%. The magnitude and response of these absorption bands to the ArF irradiation was a function of dose and implant conditions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Belmont Univ, Dept Phys, Nashville, TN 37212 USA. Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. Vanderbilt Univ, Dept Mech Engn, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Magruder, RH (reprint author), Belmont Univ, Dept Phys, Nashville, TN 37212 USA. RI Hensley, Dale/A-6282-2016 OI Hensley, Dale/0000-0001-8763-7765 NR 26 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD FEB PY 2001 VL 280 IS 1-3 BP 169 EP 176 DI 10.1016/S0022-3093(00)00372-0 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 409VG UT WOS:000167405900025 ER PT J AU Mineev-Weinstein, M Zabrodin, A AF Mineev-Weinstein, M Zabrodin, A TI Whitham-Toda hierarchy in the Laplacian growth problem SO JOURNAL OF NONLINEAR MATHEMATICAL PHYSICS LA English DT Article; Proceedings Paper CT 13th Workshop on Nonlinear Evolution Equations and Dynamical Systems (NEEDS 99) CY JUN 20-30, 1999 CL ORTHODOX ACAD, KOLIMBARY, GREECE HO ORTHODOX ACAD ID 2-DIMENSIONAL STRING THEORY; INTERFACE DYNAMICS; 2-MATRIX MODEL; FLOWS AB The Laplacian growth problem in the Limit of zero surface tension is proved to be equivalent to finding a particular solution to the dispersionless Toda lattice hierarchy. The hierarchical times are harmonic moments of the growing domain. The Laplacian growth equation itself is the quasiclassical version of the string equation that selects the solution to the hierarchy. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Joint Inst Chem Phys, Moscow 117334, Russia. Inst Theoret & Expt Phys, Moscow 117259, Russia. RP Mineev-Weinstein, M (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS-B213, Los Alamos, NM 87545 USA. NR 27 TC 12 Z9 12 U1 0 U2 1 PU NORBERT EULER PI LULEA PA LULEA UNIV TECHNOL, DEPT MATHEMATICS, SE-971 87 LULEA, SWEDEN SN 1402-9251 J9 J NONLINEAR MATH PHY JI J. Nonlinear Math. Phys. PD FEB PY 2001 VL 8 SU S BP 212 EP 218 DI 10.2991/jnmp.2001.8.s.37 PG 7 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 422MZ UT WOS:000168123800039 ER PT J AU Youngblood, GE Lewinsohn, C Jones, RH Kohyama, A AF Youngblood, GE Lewinsohn, C Jones, RH Kohyama, A TI Tensile strength and fracture surface characterization of Hi-Nicalon (TM) SiC fibers SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Environments held at the 102nd Annual Meeting of the Amer Ceram Soc CY MAY 01-02, 2000 CL ST LOUIS, MISSOURI SP Amer Ceram Soc ID CERAMIC FIBERS; SIZE AB Dimensional, tensile strength and fracture surface characterizations were carried out for a particular batch of Hi-Nicalon(TM) SiC fiber. In general, filaments with larger cross-sectional areas (equivalent diameters) had lower strengths than filaments with smaller cross-sectional areas. A cyclic variation of fiber diameter along filament lengths was discovered with a repeat distance of about 16-cm and a maximum rate of change of about +/-0.6 mum/cm. During tensile tests at room temperature, fracture originated at critical flaws that typically consisted of internal pores or carbonaceous inclusions. Well-demarcated mirror and hackle regions usually surrounded the critical flaws. With a few exceptions, the critical flaw size (a(c)) was linearly related to the mirror size (r(m)) by a(c) approximate to 0.33r(m). From fracture mechanics principles, values for the average mirror constant (A(m)) and effective fracture toughness for this batch of Hi-Nicalon(TM) fiber were estimated to be 2.99 +/- 0.33 and 1.1 +/- 0.2 MPa m(1/2), respectively. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Kyoto Univ, Inst Adv Energy, Kyoto, Japan. RP Youngblood, GE (reprint author), Pacific NW Natl Lab, MS K2-44,POB 999, Richland, WA 99352 USA. NR 19 TC 19 Z9 23 U1 2 U2 11 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 FEB PY 2001 VL 289 IS 1-2 BP 1 EP 9 DI 10.1016/S0022-3115(00)00675-9 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300002 ER PT J AU Lewinsohn, CA Henager, CH Youngblood, GE Jones, RH Lara-Curzio, E Scholz, R AF Lewinsohn, CA Henager, CH Youngblood, GE Jones, RH Lara-Curzio, E Scholz, R TI Failure mechanisms in continuous-fiber ceramic composites in fusion energy environments SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Radiation Environments held at the 102nd Annual Meeting of the Amer-Ceram-Soc CY MAY 01-02, 2000 CL ST LOUIS, MO SP Amer Ceram Soc ID BRITTLE-MATRIX COMPOSITES; SUBCRITICAL CRACK-GROWTH; SILICON-CARBIDE; HIGH-TEMPERATURE; INTERFACE; CFCCS; CREEP AB Silicon carbide composites are attractive for structural applications in fusion energy systems because of their low activation and afterheat properties, excellent high-temperature properties, corrosion resistance, and low density. These composites are relatively new materials with a limited database; however, there is sufficient understanding of their performance to identify key issues in their application. To date, dimensional changes of the constituents, microstructural evolution, radiation-enhanced creep, and slow crack growth have been identified as potential lifetime limiting mechanisms. Experimental evidence of these mechanisms, the factors that control them, and their implications on component lifetime will be discussed. (C) 2001 Published by Elsevier Science B.V. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Commiss European Communities, Joint Res Ctr, I-21020 Ispra, VA, Italy. RP Lewinsohn, CA (reprint author), Pacific NW Natl Lab, MSIN P8-15,POB 999, Richland, WA 99352 USA. EM charles.lewinsohn@pnl.gov OI Henager, Chuck/0000-0002-8600-6803 NR 37 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 EI 1873-4820 J9 J NUCL MATER JI J. Nucl. Mater. PD FEB PY 2001 VL 289 IS 1-2 BP 10 EP 15 DI 10.1016/S0022-3115(00)00676-0 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300003 ER PT J AU Serizawa, H Ando, M Lewinsohn, CA Murakawa, H AF Serizawa, H Ando, M Lewinsohn, CA Murakawa, H TI Computational analysis of creep fracture deformation in SiC/SiC composites SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Radiation Environments held at the 102nd Annual Meeting of the Amer-Ceram-Soc CY MAY 01-02, 2000 CL ST LOUIS, MO SP Amer Ceram Soc ID NICALON FIBERS; CRACK-GROWTH AB Creep fracture deformation in SiC/SiC composites was analyzed using a new computer simulation method with time-dependent interface elements. The simulation method was used to describe the crack growth deformation in SiC/SiC composite under four-point bending of single-edge-notched beam bend-bars. Two methods were used to simulate the crack growth due to fiber creep. In one method, the creep property was introduced into the interface elements by the general method of FEM analysis. In the second method, a new technique making the best use of the potential function was used. The stage-II steady-state creep deformation was simulated by both methods, and the stage-III crack growth and the transition from stage-II to stage-III could be simulated by only the new method. Additionally, the stage-I was simulated by the new method. The new method has the potential to completely simulate creep fracture deformation in SiC/SiC composite due to fiber creep. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Osaka Univ, Joining & Welding Res Inst, Ibaraki, Osaka 5670047, Japan. Osaka Univ, Grad Sch Engn, Suita, Osaka 5650871, Japan. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Osaka Univ, Joining & Welding Res Inst, 11-1 Mihogaoka, Ibaraki, Osaka 5670047, Japan. EM serizawa@jwri.osaka-u.ac.jp NR 13 TC 6 Z9 6 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 EI 1873-4820 J9 J NUCL MATER JI J. Nucl. Mater. PD FEB PY 2001 VL 289 IS 1-2 BP 16 EP 22 DI 10.1016/S0022-3115(00)00677-2 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300004 ER PT J AU Pint, BA Chitwood, LD Di Stefano, JR AF Pint, BA Chitwood, LD Di Stefano, JR TI Long-term stability of ceramics in liquid lithium SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Environments held at the 102nd Annual Meeting of the Amer Ceram Soc CY MAY 01-02, 2000 CL ST LOUIS, MISSOURI SP Amer Ceram Soc AB Two candidate materials for insulating coatings in a lithium-cooled fusion reactor have been exposed to lithium in 1000 h isothermal tests from 400-800 degreesC to determine their maximum compatibility temperature. Bulk samples of AIN + 5 wt%Y2O3 showed significant mass loss at 600 degreesC and higher temperatures. The amount of attack was reduced when AIN + 0.04 wt%Y was tested. Characterization by Auger spectroscopy of a AIN + 0.04 wt%Y specimen exposed at 600 degreesC indicated the possibility of a lithium aluminate compound formation. Bulk, polycrystalline specimens of CaO (99.9% purity) showed mass losses above 500 degreesC indicating a possible dissolution problem that had not been observed in previous short-term screening tests and is not predicted based on thermodynamic calculations. Doping of the lithium with oxygen tin the case of CaO) did not appear effective in reducing the mass loss at 600 degreesC. (C) 2001 Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Pint, BA (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Pint, Bruce/A-8435-2008 OI Pint, Bruce/0000-0002-9165-3335 NR 10 TC 15 Z9 15 U1 0 U2 3 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 FEB PY 2001 VL 289 IS 1-2 BP 52 EP 56 DI 10.1016/S0022-3115(00)00683-8 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300010 ER PT J AU Jiang, W Weber, WJ Thevuthasan, S Shutthanandan, V AF Jiang, W Weber, WJ Thevuthasan, S Shutthanandan, V TI Accumulation and recovery of disorder on silicon and carbon sublattices in ion-irradiated 6H-SiC SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Environments held at the 102nd Annual Meeting of the Amer Ceram Soc CY MAY 01-02, 2000 CL ST LOUIS, MISSOURI SP Amer Ceram Soc ID INDUCED AMORPHIZATION; CERAMICS; DAMAGE; CARBIDE; ENERGIES AB Irradiation experiments have been performed at 100, 170 and 300 K for 6H-SiC single crystals using Au2+ and He+ ions over a range of fluences. The evolution of disorder on both the Si and C sublattices has been simultaneously investigated using 0.94 MeV D+ Rutherford backscattering spectrometry (RBS) in combination with C-12(d,p) nuclear reaction analysis (NRA) in a (0 0 0 1) axial channeling geometry. At low doses, a higher rate of C disordering is observed, which is consistent with molecular dynamics simulations that suggest a smaller threshold displacement energy on the C sublattice. At higher doses for He+ irradiation, the C disordering appears to increase less rapidly than the Si disordering. Three distinct recovery stages are observed on both the Si and C sublattices in the Au2+-irradiated 6H-SiC. However, complete recovery of irradiation-induced disorder does not occur during isochronal annealing at temperatures up to 970 K. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Jiang, W (reprint author), Pacific NW Natl Lab, POB 999,MS K8-93,902 Battelle Blvd, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 30 TC 43 Z9 43 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD FEB PY 2001 VL 289 IS 1-2 BP 96 EP 101 DI 10.1016/S0022-3115(00)00687-5 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300015 ER PT J AU Afanasyev-Charkin, IV Dickerson, RM Cooke, DW Bennett, BL Gritsyna, VT Sickafus, KE AF Afanasyev-Charkin, IV Dickerson, RM Cooke, DW Bennett, BL Gritsyna, VT Sickafus, KE TI Effects of Xe ion irradiation and subsequent annealing on the structural properties of magnesium-aluminate spinel SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Environments held at the 102nd Annual Meeting of the Amer Ceram Soc CY MAY 01-02, 2000 CL ST LOUIS, MISSOURI SP Amer Ceram Soc ID MGAL2O4 SPINEL AB Single crystals of magnesium-aluminate spinel MgAl(2)O4 were irradiated with 340 keV Xe++ ions at -173 degreesC (similar to 100 K). A fluence of 1 x 10(20) Xe/m(2) created an amorphous layer at the surface of the samples. The samples were annealed for 1 h at different temperatures ranging from 130 degreesC to 880 degreesC. Recrystallization took place in the temperature interval between 610 degreesC and 855 degreesC. Transmission electron microscopy (TEM) images show two distinct layers near the surface: (1) a polycrystalline layer with columnar grain structure; and (2) a buried damaged layer epitaxial with the substrate. After annealing at 1100 degreesC for 52 days, the profile of implanted Xe ions did not change, which means that Xe ions are not mobile in the spinel structure up to 1100 degreesC. The thickness of the buried damaged layer decreased significantly in the 1100 degreesC annealed sample comparing to the sample annealed for 1 h at 855 degreesC. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Kharkiv Natl Univ, Dept Phys & Technol, UA-61077 Kharkiv, Ukraine. RP Sickafus, KE (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS-G755, Los Alamos, NM 87545 USA. NR 10 TC 12 Z9 12 U1 0 U2 2 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 FEB PY 2001 VL 289 IS 1-2 BP 110 EP 114 DI 10.1016/S0022-3115(00)00689-9 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300017 ER PT J AU Degueldre, C Pouchon, M Dobeli, M Sickafus, K Hojou, K Ledergerber, G Abolhassani-Dadras, S AF Degueldre, C Pouchon, M Dobeli, M Sickafus, K Hojou, K Ledergerber, G Abolhassani-Dadras, S TI Behaviour of implanted xenon in yttria-stabilised zirconia as inert matrix of a nuclear fuel SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Environments held at the 102nd Annual Meeting of the Amer Ceram Soc CY MAY 01-02, 2000 CL ST LOUIS, MISSOURI SP Amer Ceram Soc ID LIGHT-WATER REACTORS; RADIATION-DAMAGE; OXIDE FUELS; ION-BEAM; IRRADIATION; XE; FABRICATION; RELEASE; SPINEL; THORIA AB A zirconia-based fuel is studied for use of plutonium in light water reactors. Among the relevant properties for a nuclear fuel, efficient retention of fission products is required since the fuel matrix constitutes the first barrier against fission product release. To study the retention of xenon, its stopping power and its diffusion properties within (Er,Y,Pu,Zr)O-2 potential inert matrix fuel (IMF) are investigated. Stopping and range of ions in matter (SRIM) calculations were carried out to estimate the average penetration depth of Xe ions as a function of their incident energy and of the material composition. To study its diffusion properties, Xe was implanted into yttria-stabilised zirconia (YSZ) to a depth of around 100 nm from the surface. After successive heat treatments to a maximum temperature of 1773 K, quantitative Xe depth profiles were determined by Rutherford backscattering. No profile modification by diffusion was observed. The behaviour of Xe is investigated at the subnanoscopic level and compared with the results obtained with zirconia samples implanted with Cs or I, as well as with Xe in UO2. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. RP Degueldre, C (reprint author), Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RI Pouchon, Manuel Alexandre/J-7213-2015 NR 33 TC 39 Z9 40 U1 0 U2 11 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 FEB PY 2001 VL 289 IS 1-2 BP 115 EP 121 DI 10.1016/S0022-3115(00)00690-5 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300018 ER PT J AU Shutthanandan, V Thevuthasan, S Young, JS Orlando, TM Weber, WJ AF Shutthanandan, V Thevuthasan, S Young, JS Orlando, TM Weber, WJ TI Hydrogen-damage interactions in yttria-stabilized zirconia SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Radiation Environments held at the 102nd Annual Meeting of the Amer-Ceram-Soc CY MAY 01-02, 2000 CL ST LOUIS, MO SP Amer Ceram Soc AB Hydrogen diffusion and accumulation in oxidized Zr(ZrO(2)) and oxide-metal interfaces lead to hydrogen induced cracking in Zr-based compounds that are extensively used in nuclear reactors. In this study, the interaction of hydrogen with irradiation damage in (001) single crystals of yttria-stabilized zirconia (Y-ZrO(2)) has been investigated as a function of damage accumulation and temperature. Samples were irradiated with 40 keV hydrogen ions at a temperature of 120 K to ion fluences of 5 x 10(16) and 1 x 10(17) ions/cm(2), and isochronal experiments were performed in the temperature range from 300 to 770 K in 100 K steps. Damage accumulation and hydrogen profile measurements indicate unusual damage recovery behavior, pinning of hydrogen by damage, and surface deformation due to hydrogen blisters and bubbles. (C) 2001 Published by Elsevier Science B.V. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Shutthanandan, V (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,MSIN K8-93, Richland, WA 99352 USA. EM shuttha@pnl.gov RI Weber, William/A-4177-2008 OI Weber, William/0000-0002-9017-7365 NR 15 TC 3 Z9 3 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD FEB PY 2001 VL 289 IS 1-2 BP 128 EP 135 DI 10.1016/S0022-3115(00)00692-9 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300020 ER PT J AU Begg, BD Hess, NJ McCready, DE Thevuthasan, S Weber, WJ AF Begg, BD Hess, NJ McCready, DE Thevuthasan, S Weber, WJ TI Heavy-ion irradiation effects in Gd-2(Ti2-xZrx)O-7 pyrochlores SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Environments held at the 102nd Annual Meeting of the Amer Ceram Soc CY MAY 01-02, 2000 CL ST LOUIS, MISSOURI SP Amer Ceram Soc ID SELF-RADIATION DAMAGE; GD2TI2O7 AB Gd-2(Ti2-xZrx)O-7 samples with 0 less than or equal to x less than or equal to 1.5 were single-phase and pyrochlore structured after sintering at 1600 degreesC in air. The Gd2Zr2O7 (x = 2) end member predominantly displayed an anion deficient-fluorite structure. Raman spectroscopy indicated that the level of short-range fluorite-like disorder in the unirradiated Gd-2(Ti2-xZrx)O-7 samples increased significantly as Zr was substituted for Ti, despite the retention of a long-range pyrochlore structure for samples with 0 less than or equal to x less than or equal to 1.5. Glancing-incidence X-ray diffraction indicated that pyrochlores with an ionic radii ratio r(A)/r(B) less than or equal to 1.52(x greater than or equal to 1.5) were transformed into a radiation resistant defect-fluorite structure after irradiation at room temperature with 2 MeV AU(2+) to fluence of 5 ions/nm(2). As the ionic radii ratio of the pyrochlore increased beyond r(A)/r(B) > 1.52, the defect-fluorite structure became increasingly unstable with respect to the amorphous state under identical irradiation conditions. Crown Copyright (C) 2001 Published by Elsevier Science B.V. All rights reserved. C1 Australian Nucl Sci & Technol Org, Div Mat, Menai, NSW 2234, Australia. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Begg, BD (reprint author), Australian Nucl Sci & Technol Org, Div Mat, PMB1, Menai, NSW 2234, Australia. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Hess, Nancy/0000-0002-8930-9500 NR 9 TC 115 Z9 117 U1 3 U2 22 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 FEB PY 2001 VL 289 IS 1-2 BP 188 EP 193 DI 10.1016/S0022-3115(00)00696-6 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300024 ER PT J AU Thevuthasan, S Jiang, W Shutthanandan, V Weber, WJ AF Thevuthasan, S Jiang, W Shutthanandan, V Weber, WJ TI Accumulation and thermal recovery of disorder in Au(2+)-irradiated SrTiO(3) SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 6th International Symposium on Fabrication and Properties of Ceramics for Fusion Energy and Other High Radiation Environments held at the 102nd Annual Meeting of the Amer-Ceram-Soc CY MAY 01-02, 2000 CL ST LOUIS, MO SP Amer Ceram Soc ID BEAM-AMORPHIZED SRTIO3; IMPLANTED SRTIO3; EPITAXIAL RECRYSTALLIZATION; ION; IRRADIATION; CERAMICS; OXIDES AB Damage accumulation and thermal recovery processes have been investigated in single crystal SrTiO(3)(100) irradiated with 1.0 MeV AU(2+) using in situ Rutherford backscattering spectrometry in channeling geometry (RBS/C). Samples were irradiated at temperatures of 170 and 300 K with ion fluences ranging from 0.10 to 0.40 AU(2+) /nm(2). The in situ RBS/C analysis indicates that the relative disorder shows a strong sigmoidal dependence on ion dose. After an ion fluence of 0.30 Au(2+)/nm(2) at 170 K, the buried region at the damage peak (similar to 60 nm) becomes fully amorphous, which corresponds to a dose of similar to0.8 displacement per atom (dpa). For irradiation at 300 K, an ion fluence of 0.40 Au(2+)/nm(2) (similar to1.1 dpa) is necessary to achieve an amorphous state at the damage peak. An analysis of the defects dechanneling factor suggests that the irradiated regions consist mostly of interstitial atoms or amorphous clusters. In situ thermal annealing experiments were performed to study damage recovery processes up to a maximum temperature of 870 K. The thermal recovery processes occur over a broad temperature range, and the disorder created by low ion fluences, 0.10-0.27 Au(2+) /nm(2), is almost completely recovered after annealing at 870 K. (C) 2001 Published by Elsevier Science B.V. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Thevuthasan, S (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,MSIN K8-93, Richland, WA 99352 USA. EM theva@pnl.gov RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 20 TC 15 Z9 15 U1 0 U2 3 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 FEB PY 2001 VL 289 IS 1-2 BP 204 EP 209 DI 10.1016/S0022-3115(00)00699-1 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412GH UT WOS:000167546300027 ER PT J AU Begg, BD Hess, NJ Weber, WJ Devanathan, R Icenhower, JP Thevuthasan, S McGrail, BP AF Begg, BD Hess, NJ Weber, WJ Devanathan, R Icenhower, JP Thevuthasan, S McGrail, BP TI Heavy-ion irradiation effects on structures and acid dissolution of pyrochlores SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID SELF-RADIATION DAMAGE; GD2TI2O7; AMORPHIZATION; CAZRTI2O7 AB The temperature dependence of the critical dose for amorphization, using 0.6 MeV Bi+ ions, for A(2)Ti(2)O(7) pyrochlores, in which A=Y, Sm, Gd and Lu, exhibits no significant effect of A-site ion mass or size. The room temperature dose for amorphization was found to be similar to0.18 dpa in each case. After irradiation with 2 MeV Au2+ ions glancing-incidence X-ray diffraction (XRD) revealed that each pyrochlore underwent an irradiation-induced structural transformation to fluorite in conjunction with amorphization. The effect of amorphization on the dissolution rates of fully dense pyrochlores, at 90 degreesC and pH 2 (nitric acid) varied from a factor of 10 to 15 increase for Gd2Ti2O7 to none for Y2Ti2O7 Significant differences were observed in the A-site dissolution rates from the crystalline pyrochlores, indicating differences in the manner in which the A-site cations are incorporated into the pyrochlore structure. These indications were supported by Raman spectroscopy. Crown Copyright (C) 2001 Published by Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Begg, BD (reprint author), Australian Nucl Sci & Technol Org, Div Mat, PMB 1, Menai, NSW 2234, Australia. RI Weber, William/A-4177-2008; Icenhower, Jonathan/E-8523-2011; Devanathan, Ram/C-7247-2008; OI Weber, William/0000-0002-9017-7365; Devanathan, Ram/0000-0001-8125-4237; Hess, Nancy/0000-0002-8930-9500 NR 14 TC 72 Z9 74 U1 4 U2 25 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 FEB PY 2001 VL 288 IS 2-3 BP 208 EP 216 DI 10.1016/S0022-3115(00)00708-X PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 412QJ UT WOS:000167565600014 ER PT J AU Marshall, RC Powers-Risius, P Reutter, BW Taylor, SE VanBrocklin, HF Huesman, RH Budinger, TF AF Marshall, RC Powers-Risius, P Reutter, BW Taylor, SE VanBrocklin, HF Huesman, RH Budinger, TF TI Kinetic analysis of I-125-iodorotenone as a deposited myocardial flow tracer: Comparison with Tc-99m-sestamibi SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE PET; SPECT; myocardial perfusion ID RABBIT HEART; TL-201 EXTRACTION; RETENTION; ISONITRILE; ROTENONE; BINDING; BLOOD; TEBOROXIME; DEPENDENCE; CELLS AB The goal of this investigation was to assess the accuracy of 7'-Z-[I-125]iodorotenone (I-125-iodorotenone) as a new deposited myocardial flow tracer and compare the results with those for Tc-99m-sestamibi. Methods: The kinetics of these two flow tracers were evaluated in 25 isolated, erythrocyte- and albumin-perfused rabbit hearts over a flow range relevant to patients. The two flow tracers and a vascular reference tracer (I-131-albumin) were introduced simultaneously as a compact bolus through a port just above the aortic cannula in the absence of tracer recirculation. Myocardial extraction, retention, washout, and uptake parameters were computed from the venous outflow curves using the multiple-indicator dilution technique and spectral analysis. Results: The extraction of I-125-iodorotenone was much higher than the extraction of Tc-99m-sestamibi (0.84 +/- 0.05 vs. 0.48 +/- 0.10, respectively, P < 0.001). I-125-iodorotenone extraction was also less affected by flow than was Tc-99m-sestamibi (P < 0.001). Net retention of I-125-iodorotenone was significantly greater than Tc-99m-sestamibi net retention at 1 min (0.77 +/- 0.08 vs. 0.41 +/- 0.11, respectively, P < 0.001) and 26 min (0.46 +/- 0.13 vs. 0.27 +/- 0.11, respectively, P < 0.001) after tracer injection. Flow had less effect on I-125-iodorotenone net retention than on Tc-99m-sestamibi net retention 1 min after tracer injection (P < 0.04). However, at 26 min, flow had an equivalent effect on the retention of both flow tracers (P < 0.4). The relationship between I-125-iodorotenone and Tc-99m-sestamibi washout was complex and depended on elapsed time after isotope introduction and perfusion rate. Reflecting the favorable extraction and retention characteristics of I-125-iodorotenone, both its maximum myocardial uptake and its 26-min uptake were more closely related to flow than were those of Tc-99m-sestamibi (P < 0.001 for both comparisons). Conclusion: The extraction and retention of I-125-iodorotenone were greater than those of Tc-99m-sestamibi, making I-125-iodorotenone the superior flow tracer in the isolated rabbit heart. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. No Calif Hlth Care Sys t, Martinez, CA USA. RP Marshall, RC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, 1 Cyclotron Rd,MS55-121, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [P01 HL25840, R01 HL60877] NR 30 TC 28 Z9 28 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD FEB PY 2001 VL 42 IS 2 BP 272 EP 281 PG 10 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 400TT UT WOS:000166888300020 PM 11216526 ER PT J AU Krauss, RM AF Krauss, RM TI Atherogenic lipoprotein phenotype and diet-gene interactions SO JOURNAL OF NUTRITION LA English DT Article; Proceedings Paper CT Experimental Biology 2000 Meeting CY APR 14-18, 2000 CL SAN DIEGO, CALIFORNIA SP Amer Soc Nutr Sci DE cholesterol; LDL; diet; fat; carbohydrate; lipoprotein subclasses ID LOW-DENSITY-LIPOPROTEIN; CORONARY-ARTERY DISEASE; LDL SUBCLASS PHENOTYPES; LOW-FAT DIET; PARTICLE-SIZE; MYOCARDIAL-INFARCTION; HEART-DISEASE; WOMEN TWINS; MEN; PATTERNS AB Studies employing analysis of LDL subclasses have demonstrated heterogeneity of the LDL response to low fat, high carbohydrate diets in healthy nonobese subjects. In individuals with a genetically influenced atherogenic lipoprotein phenotype, characterized by a predominance of small dense LDL (LDL subclass pattern B), lowering of plasma LDL cholesterol levels by diets with less than or equal to 24% fat has been found to represent a reduction in numbers of circulating mid-sized and small LDL particles, and hence an expected lowering of cardiovascular disease risk. In contrast, in the majority of healthy individuals with larger LDL (pattern A, found in similar to 70% of men and a larger percentage of women), a significant proportion of the low fat diet-induced reduction in plasma LDL cholesterol is made by depletion of the cholesterol content of LDL particles. This change in LDL composition is accompanied by a shift from larger to smaller LDL particle diameters. Moreover, with progressive reduction of dietary fat and isocaloric substitution of carbohydrate, an increasing number of subjects with pattern A convert to the pattern B phenotype. Studies in families have indicated that susceptibility to induction of pattern B by low fat diets is under genetic influence. Thus, diet-gene interactions affecting LDL subclass patterns may contribute to substantial interindividual variability in the effects of low fat diets on coronary heart disease risk. C1 Univ Calif Berkeley, Div Life Sci, Dept Mol & Nucl Med, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Krauss, RM (reprint author), Univ Calif Berkeley, Div Life Sci, Dept Mol & Nucl Med, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [HL 18574] NR 41 TC 49 Z9 49 U1 1 U2 3 PU AMER INST NUTRITION PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-3166 J9 J NUTR JI J. Nutr. PD FEB PY 2001 VL 131 IS 2 BP 340S EP 343S PG 4 WC Nutrition & Dietetics SC Nutrition & Dietetics GA 400AB UT WOS:000166845500024 PM 11160558 ER PT J AU Tufo, HM Fischer, PF AF Tufo, HM Fischer, PF TI Fast parallel direct solvers for coarse grid problems SO JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING LA English DT Article DE direct solver; sparse factorization; nested dissection; parallel computing; coarse grid problems ID DOMAIN DECOMPOSITION METHODS AB We have developed a fast direct solver for parallel solution of coarse grid problems, Ax = b, such as arise when domain decomposition or multigrid methods are applied to elliptic partial differential equations in d space dimensions. The approach is based on a (quasi-) sparse factorization of the inverse of A. If A is n x n and the number of processors is P, the algorithm requires O(n(gamma)Y log P) time for communication and O(n(1+gamma)/P) time for computation, where gamma drop [GRAPHICS] The method is particularly suited to leading-edge multicomputer systems having thousands of processors. It achieves minimal message startup costs and substantially reduced message volume and arithmetic complexity compared with competing methods, which require O(n log P) time for communication and O(n(1+gamma)) or O(n(2)/P) lime for computation. Timings on the Intel Paragon and ASCI-Red machines reflect these complexity estimates. (C) 2001 Academic Press. C1 Univ Chicago, Dept Comp Sci, Chicago, IL 60637 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Tufo, HM (reprint author), Univ Chicago, Dept Comp Sci, 1100 E 58th St,Ryerson 152, Chicago, IL 60637 USA. EM hmt@asci.uchicago.edu; fischer@mcs.anl.gov NR 20 TC 45 Z9 45 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 0743-7315 J9 J PARALLEL DISTR COM JI J. Parallel Distrib. Comput. PD FEB PY 2001 VL 61 IS 2 BP 151 EP 177 DI 10.1006/jpdc.2000.1676 PG 27 WC Computer Science, Theory & Methods SC Computer Science GA 398GU UT WOS:000166749200001 ER PT J AU Itoh, K Holroyd, RA Nishikawa, M AF Itoh, K Holroyd, RA Nishikawa, M TI Ion mobilities in supercritical ethane, xenon, and carbon dioxide SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID LIQUID XENON; TEMPERATURE; FLUIDS; GAS; CO2; AR AB The mobility of positive ions was measured in supercritical ethane, xenon, and carbon dioxide as a function of pressure at several temperatures. In supercritical CO(2) the mobility of negative ions was also measured. Radii of the moving clusters were calculated with a hydrodynamic compressible continuum model that takes the enhancement in density and viscosity near the ions into account. The results show that positive ions move with a large solvation shell. Changes in size of this shell occur as a function of temperature and pressure. The largest radii at each temperature are found to occur at the pressure corresponding to the maximum in the isothermal compressibility. For positive ions the first solvation shell is totally filled under all conditions. C1 Univ Tokyo, Dept Pure & Appl Sci, Tokyo 1538902, Japan. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Kanagawa Inst Technol, Fac Engn, Atsugi, Kanagawa 2430292, Japan. RP Holroyd, RA (reprint author), Univ Tokyo, Dept Pure & Appl Sci, Tokyo 1538902, Japan. NR 32 TC 25 Z9 25 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD FEB 1 PY 2001 VL 105 IS 4 BP 703 EP 709 DI 10.1021/jp003451e PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 397KW UT WOS:000166695700006 ER PT J AU Vargas, R Garza, J Dixon, D Hay, BP AF Vargas, R Garza, J Dixon, D Hay, BP TI C(sp(2))-C(aryl) bond rotation barrier in N-methylbenzamide SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ION SEQUESTERING AGENTS; HYDROGEN-BOND; BASIS-SETS; POTENTIOMETRIC EVALUATION; MOLECULAR CALCULATIONS; ENTEROBACTIN ANALOGS; FORCE-FIELD; DENSITY; COMPLEXES; APPROXIMATION AB The potential energy surfaces at different levels of ab initio electronic structure theory with correlation effects included are reported for rotation about the C(sp(2))-C(aryl) bond in N-methylbenzamide. The results reveal a minimum at a C=C-C=O dihedral angle of +/-28 degrees with barrier heights (MP2/aug-cc-pVTZ//BLYP/DZVP2/A2) of 0.48 kcal/mol at 0 degrees and 2.80 kcal/mol at 90 degrees. Fully optimized geometries are in good agreement with crystal structure data, and potential energy surfaces are consistent with the experimental dihedral angle distribution. The results are used to assign MM3 force field parameters to allow calculation on N-methylbenzamide and other benzamide derivatives. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Autonoma Metropolitana Azcapotzalco, Dept Quim, Div Ciencias Basicas & Ingn, Mexico City 09340, DF, Mexico. RP Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Garza, Jorge/H-9395-2016 OI Garza, Jorge/0000-0003-4249-6078 NR 53 TC 20 Z9 20 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD FEB 1 PY 2001 VL 105 IS 4 BP 774 EP 778 DI 10.1021/jp003340f PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 397KW UT WOS:000166695700015 ER PT J AU Bailly, A Amoureux, JP Wiench, JW Pruski, M AF Bailly, A Amoureux, JP Wiench, JW Pruski, M TI Structural analysis of ZON-type aluminophosphates by solid state NMR SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID HETERONUCLEAR DIPOLAR INTERACTIONS; ANGLE-SPINNING NMR; POWDER DIFFRACTION; QUADRUPOLAR NUCLEI; MOLECULAR-SIEVES; REDOR; SENSITIVITY; SPIN-1/2; SPINS; MAS AB Solid-state NMR spectroscopy has been used to study the new aluminophosphate material AlPO4-ZON. Highly resolved multiple quantum magic-angle spinning NMR spectra showed all four Al sites in the framework of AlPO4-ZON. Additional Al-27 resonances were detected in some samples. They were assigned to an impurity phase of AlPO4-AFR and to six-coordinated aluminum in the extra-lattice positions. High-speed MAS NMR of H-1 yielded the OH concentration in the samples synthesized from the fluoride-modified gels of different pH, The location of fluorine in the AlPO4-ZON framework has been verified by measuring the internuclear distances between F-19 and all Al-27 sites using the MQ-REDOR technique. MQ-REDOR has been also used to measure the distances between H-1 and Al-27 nuclei in this material. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Univ Lille 1, F-59655 Villeneuve Dascq, France. RP Pruski, M (reprint author), Iowa State Univ, Ames Lab, 230 Spedding Hall, Ames, IA 50011 USA. NR 21 TC 8 Z9 8 U1 0 U2 3 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 FEB 1 PY 2001 VL 105 IS 4 BP 773 EP 776 DI 10.1021/jp0027795 PG 4 WC Chemistry, Physical SC Chemistry GA 397KY UT WOS:000166695900006 ER PT J AU Dang, LX AF Dang, LX TI A mechanism for ion transport across the water/dichloromethane interface: A molecular dynamics study using polarizable potential models SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID LIQUID-LIQUID INTERFACE; COMPUTER-SIMULATIONS; WATER CLUSTERS; VAPOR; CHLOROFORM; ENERGY AB In this work, we used molecular dynamics techniques and potential of mean force approaches to compute the ion transfer free energy for the water/dichloromethane liquid-liquid interface. We used polarizable potential models to describe the interactions among the species. Both foward and reverse directions simulations were carried out to evaluate the differences in the free energy profiles. On the basis of the results of our calculations, we have proposed a mechanism that describes the transport of a chloride inn across the interface. The computed ion transfer free energy is 14 +/- 2 kcal/mol, which is in qualitative agreement with the experimentally reported value of 10 +/- 1 kcal/mol. A smooth transition from the aqueous phase to the nonaqueous phase on the free energy profile clearly indicates that the ion transfer mechanism is a nonactivated process. The computed hydration number for the chloride ion indicates that some water molecules are associated with the ion inside the nonaqueous phase. This result is in excellent agreement with the experimental interpretation of the ion transfer mechanism reported recently by Osakai et al. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Dang, LX (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,Mail Stop K8-91, Richland, WA 99352 USA. NR 31 TC 51 Z9 51 U1 2 U2 11 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 FEB 1 PY 2001 VL 105 IS 4 BP 804 EP 809 DI 10.1021/jp003991b PG 6 WC Chemistry, Physical SC Chemistry GA 397KY UT WOS:000166695900010 ER PT J AU Yezdimer, EM Chialvo, AA Cummings, PT AF Yezdimer, EM Chialvo, AA Cummings, PT TI Examination of chain length effects on the solubility of alkanes in near-critical and supercritical aqueous solutions SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; EFFECTIVE PAIR POTENTIALS; MONTE-CARLO SIMULATION; FREE-ENERGIES; THERMODYNAMIC PROPERTIES; PHASE COEXISTENCE; LIQUID WATER; DEPENDENCE; MIXTURES; TEMPERATURES AB Molecular dynamics simulations of infinitely dilute aqueous solutions of butane and octane were conducted in both the subcritical and supercritical regions. The free energy of hydration of each alkane species was calculated and compared with predictions from a recently proposed equation of state. The results suggest that near the critical temperature of water (along a given isobar), the trends in the free energy of hydration for a series of acyclic alkanes reverse with increasing temperature. This implies that larger chains (such as octane) have a greater solubility than smaller chains (such as butane). The effects of alternative combining rules other than the standard Lorentz-Berthelot relationships on the free energy of hydration were also examined. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Yezdimer, EM (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Cummings, Peter/B-8762-2013; OI Cummings, Peter/0000-0002-9766-2216; Chialvo, Ariel/0000-0002-6091-4563 NR 67 TC 12 Z9 14 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 FEB 1 PY 2001 VL 105 IS 4 BP 841 EP 847 DI 10.1021/jp002610r PG 7 WC Chemistry, Physical SC Chemistry GA 397KY UT WOS:000166695900014 ER PT J AU Yan, M Rothberg, L Callender, R AF Yan, M Rothberg, L Callender, R TI Femtosecond dynamics of rhodopsin photochemistry probed by a double pump spectroscopic approach SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID 1ST STEP; ULTRAFAST SPECTROSCOPY; ENERGY-STORAGE; VISION; BACTERIORHODOPSIN; ISOMERIZATION; ISORHODOPSIN; PHOTOISOMERIZATION; EVENTS AB Femtosecond pump-probe measurements of the excitation pathway of bovine rhodopsin to bathorhodopsin show varying transient events in the photoinduced absorption spectrum. In the spectral region where bathorhodopsin absorption dominates in the rhodopsin-batharhodopsin difference spectrum, subpicosecond (200-600 fs) and 3 ps signals are observed. In the region where rhodopsin absorption dominates, a 3-5 ps transient is observed, which follows rhodopsin repopulation. To unravel the different models of the rhodopsin-bathorhodopsin dynamics that have been proposed to explain these transient observations, we have employed a three-beam experiment. The first pump beam launches the photochemistry, a second pump pulse interrupts the spontaneous evolution of the trajectory of excited rhodopsin at a delayed time from the first pump pulse, and a weak third beam probes changes in the amount of bathorhodopsin that is formed in response to the second pump beam. We first find that bathorhodopsin can be photoexcited, presumably back to rhodopsin, by reversing the initial photochemistry. We find that bathorhodopsin is formed very promptly (within the 300 fs resolution of our experiments). Surprisingly, the kinetics in the absorbance signal near 605 nm is found to be the superposition of two independent signals, one being characterized by events on the subpicosecond time scale and the other at 3 ps. The results suggest that the trajectory of excited rhodopsin splits into two pathways very early: one of which results in bathorhodopsin formation on the similar to 200 fs time scale and another which lives in the excited state for ca. 3 ps before undergoing internal conversion to rhodopsin. C1 Yeshiva Univ Albert Einstein Coll Med, Dept Biochem, Bronx, NY 10461 USA. Univ Rochester, Dept Chem, Rochester, NY 14627 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Callender, R (reprint author), Yeshiva Univ Albert Einstein Coll Med, Dept Biochem, 1300 Morris Pk Ave, Bronx, NY 10461 USA. NR 21 TC 26 Z9 28 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 FEB 1 PY 2001 VL 105 IS 4 BP 856 EP 859 DI 10.1021/jp002036j PG 4 WC Chemistry, Physical SC Chemistry GA 397KY UT WOS:000166695900017 ER PT J AU Wheldon, C Walker, PM Chowdhury, P Shestakova, I D'Alarcao, R Ahmad, I Carpenter, MP Cullen, DM Janssens, RVF Khoo, TL Kondev, FG Lister, CJ Pearson, CJ Podolyak, Z Seweryniak, D Wiedenhoever, I AF Wheldon, C Walker, PM Chowdhury, P Shestakova, I D'Alarcao, R Ahmad, I Carpenter, MP Cullen, DM Janssens, RVF Khoo, TL Kondev, FG Lister, CJ Pearson, CJ Podolyak, Z Seweryniak, D Wiedenhoever, I TI First observation of a rotational band in neutron-rich Lu-180 SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Letter ID BETA-DECAY; K-ISOMER; NUCLEOSYNTHESIS; TA-180M; NUCLEI; SEARCH; TRAPS AB Rotational states assigned to a K-pi = (5(+)) band in Lu-180(71)109 have been populated in the decay of a t(1/2) greater than or equal to 1 ms, two-quasiparticle isomer. Delayed gamma -ray and x-ray coincidences were observed with the Gammasphere array following the deep-inelastic reaction U-238(92) + Hf-180(72). Gamma-ray coincidence and intensity data, comparisons with the level structure of the neighbouring odd-odd isotone, a g-factor analysis and theoretical predictions of multi-quasiparticle states, all support the assignment of the new band to the neutron-rich nucleus Lu-180. C1 Univ Liverpool, Dept Phys, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England. Univ Massachusetts, Dept Phys, Lowell, MA 01854 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Manchester, Dept Phys & Astron, Manchester M13 9PL, Lancs, England. RP Univ Liverpool, Dept Phys, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. EM cw@ns.ph.liv.ac.uk RI Wheldon, Carl/F-9203-2013; Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 16 TC 7 Z9 7 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 EI 1361-6471 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD FEB PY 2001 VL 27 IS 2 BP L13 EP L17 DI 10.1088/0954-3899/27/2/101 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 402WE UT WOS:000167010500001 ER PT J AU McAfee, WJ Bass, BR Williams, PT AF McAfee, WJ Bass, BR Williams, PT TI Shallow flaws under biaxial loading conditions - Part I: The effect of specimen size on fracture toughness values obtained from large-scale cruciform specimens SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB A technology to determine shallow-flaw fracture toughness of reactor pressure vessel (RPV) steels is being developed This technology is for application to the safety assessment of RPVs containing postulated shallow-surface pm vs. It has been shown that relaxation of crack-tip constraint causes shallow-flaw fracture toughness of RPV material to have a higher mean value than that for deep flaws in the lower transition temperature, region. Cruciform beam specimens developed at Oak Ridge National Laboratory (ORNL) introduce far-field, out-of-plane biaxial stress components in the test section that approximates the nonlinear stresses resulting from pressurized-thermal-shock (PTS) loading of an RPV. The biaxial stress component has been shown to increase stress triaxiality (constraint) at the crack tip, and thereby reduce the shallow-flaw fracture toughness enhancement. The cruciform specimen pe,mits controlled application of biaxial loading ratios, resulting in controlled variation of crack-tip constraint. An extensive matrix of intermediate-scale cruciform specimens with a uniform depth surface flaw, was previously tested and demonstrated a continued decrease in shallow-flaw fracture toughness with increasing biaxial loading. This paper describes the test results for. a series of large-scale cruciform specimens with a uniform depth surface flaw. These specimens weve all of the same size with the same depth flaw and were tested at the same temperature and biaxial load ratio (1:1). The configuration is the same as the previous set of intermediate-scale tests, brit has been scaled upward in size by 150 percent. These tests demonstrated the effect of biaxial lending and specimen size on shallow-flaw fracture toughness in the lower transition temperature region for RPV materials. For specimens tested under frill biaxial (I:1) loading at test temperatures in the range of 23 degreesF (-5 degreesC) to 34 degreesF (1 degreesC), toughness was reduced by approximately 15 percent for a 150-percent increase in specimen size. This decrease was slightly greater than the predicted reduction for this increase in specimen size. The size corrections for 1/2T C(T) specimens did not predict the experimentally determined mean toughness values for larger size shallow-flaw specimens tested under biaxial (1:I) loading in the lower transition temperature region. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP McAfee, WJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 17 TC 4 Z9 4 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD FEB PY 2001 VL 123 IS 1 BP 10 EP 24 DI 10.1115/1.1343910 PG 15 WC Engineering, Mechanical SC Engineering GA 412QX UT WOS:000167566800003 ER PT J AU Williams, PT Bass, BR McAfee, WJ AF Williams, PT Bass, BR McAfee, WJ TI Shallow flaws under biaxial loading conditions - Part II: Application of a Weibull stress analysis of the cruciform bend specimen using a hydrostatic stress criterion SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID STATISTICAL-ANALYSIS; MULTIAXIAL FRACTURE; TOUGHNESS AB Cruciform beam fracture mechanics specimens have been developed in the Heavy Section Steel Technology Program at Oak Ridge National Laboratory to introduce a prototypic, far-field, out-of-plane biaxial bending stress component in the test section that approximates the nonlinear biaxial stresses resulting from pressurized-thermal-shock ol pressure-temperature loading of a nuclear reactor pressure vessel (RPV). Matrices of cruciform beam tests were developed to investigate and quantify the effects of temperature, biaxial loading, and specimen size on fracture initiation toughness of two-dimensional (constant-depth) shallow surface flaws. Tests were conducted under biaxial load ratios ranging from uniaxial to equibiaxial. These tests demonstrated that biaxial loading can have a pronounced effect on shallow-flaw fracture toughness in the lower transition temperature region for RPV materials. Two and three-parameter Weibull models have been calibrated using a new scheme (developed at the University of Illinois) that maps toughness data from test specimens with distinctly different levels of crack-tip constraint to a small-scale-yielding Weibull stress space. These models, with a new hydrostatic stress criterion in place of the more commonly used maximum principal stress in the kernel of the Weibull stress integral definition, have been shown to correlate the experimentally observed biaxial effect in cruciform specimens, thereby providing a scaling mechanism between uniaxial and biaxial lending states. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Williams, PT (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 30 TC 4 Z9 4 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD FEB PY 2001 VL 123 IS 1 BP 25 EP 31 DI 10.1115/1.1344235 PG 7 WC Engineering, Mechanical SC Engineering GA 412QX UT WOS:000167566800004 ER PT J AU Simonen, FA Gosselin, SR AF Simonen, FA Gosselin, SR TI Life prediction and monitoring of nuclear power plant components for service-related degradation SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB This paper describes industry programs to manage structural degradation and to justify continued operation of nuclear components,when unexpected degradation has been encountered due to design materials and/or operational problems. Other issues have been related to operation of components beyond their original design life in cases where there is no evidence of fatigue crack initiation or other forms,ls of structural degradation. Data from plant operating experience have been applied in combination with inservice inspections and degradation management programs to ensure that the degradation mechanisms do not adversely impact plant safety. Probabilistic fracture I,mechanics calculations are presented to demonstrate how component failure probabilities carl be managed through augmented inservice inspection programs. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Simonen, FA (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 25 TC 1 Z9 1 U1 1 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD FEB PY 2001 VL 123 IS 1 BP 58 EP 64 DI 10.1115/1.1344237 PG 7 WC Engineering, Mechanical SC Engineering GA 412QX UT WOS:000167566800008 ER PT J AU Brinkman, CR AF Brinkman, CR TI Elevated-temperature mechanical properties of an advanced-type 316 stainless steel SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers (Joint w/ICPVT) CY AUG 01-05, 1999 CL BOSTON, MASSACHUSETTS SP Amer Soc Mech Engineers AB Type 316FR stainless steel is a candidate material for the Japanese demonstration fast breeder reactor plant to be built in Japan early in the next century. Like type 316L(N), it is a low-carbon grade of stainless steel with a more closely specified nitrogen content and chemistry optimized to enhance elevated-temperature performance. Early in 1994, under sponsorship of The Japan Atomic Power Company, work was initiated at Oak Ridge National Laboratory (ORNL) aimed at obtaining an elevated-temperature mechanical properties database on a single heat of this material. The product form was 50-mm plate manufactured by the Nippon Steel Corporation. Data include results from long-term creep-rupture tests conducted at temperatures of 500 to 600 degreesC with test times up to nearly 40.000 h, continuous-cycle strain-controlled fatigue test results over the same temperature range, limited creep-fatigue data at 550 and 600 degreesC, and tensile test properties from room temperature to 650 degreesC. The ORNL data were compared with data obtained from several different heats and product forms of this material obtained at Japanese laboratories. The data were also compared with results from predictive equations developed for this material and with data available for types 316 and 316L(N) stainless steel. C1 Oak Ridge Natl Lab, Met & Ceram Div, Oak Ridge, TN 37831 USA. RP Brinkman, CR (reprint author), Oak Ridge Natl Lab, Met & Ceram Div, Oak Ridge, TN 37831 USA. NR 13 TC 12 Z9 12 U1 0 U2 8 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 FEB PY 2001 VL 123 IS 1 BP 75 EP 80 DI 10.1115/1.1343911 PG 6 WC Engineering, Mechanical SC Engineering GA 412QX UT WOS:000167566800011 ER PT J AU Bushaw, BA Nortershauser, W Muller, P Wendt, K AF Bushaw, BA Nortershauser, W Muller, P Wendt, K TI Diode-laser-based resonance ionization mass spectrometry of the tong-lived radionuclide Ca-41 with < 10(-12) sensitivity SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article ID BONE-RESORPTION; SPECTROSCOPY; ISOTOPES; TRACER AB There are a number of applications requiring measurement of the long-lived radionuclide Ca-41 at isotopic abundance, relative to Ca-40, in the range of 10(-8) to 10(-16). The long lifetime and electron-capture decay mode make radio-analytical measurements impractical and conventional mass spectrometric methods can not overcome isobaric interferences such as K-41(+) or (CaH+)-Ca-40 at these levels. We approach this problem by combining laser-based resonance ionization spectroscopy with mass spectrometry. Using high-resolution single-mode lasers for resonant excitation and an intense non-resonant laser for ionization of the selectively created excited-state atoms, it is possible to essentially eliminate interference from isobars and to obtain additional optical isotopic selectivity, which can be combined with that of the mass spectrometer. Single-, double-, and triple-resonance excitation schemes have been investigated experimentally and theoretically, and it is found that performance with respect to both selectivity and sensitivity increases dramatically with each additional resonance step. Thus far, triple-resonance measurements have demonstrated minimum detectable isotopic abundance of 2.5.10(-13) with detection limits of -2.10(5) atoms. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RP Bushaw, BA (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Mueller, Peter/E-4408-2011; Wendt, Klaus/D-7306-2011; Nortershauser, Wilfried/A-6671-2013 OI Mueller, Peter/0000-0002-8544-8191; Wendt, Klaus/0000-0002-9033-9336; Nortershauser, Wilfried/0000-0001-7432-3687 NR 20 TC 19 Z9 19 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 FEB PY 2001 VL 247 IS 2 BP 351 EP 356 DI 10.1023/A:1006761819893 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 410YR UT WOS:000167469100014 ER PT J AU Pacheco, JE AF Pacheco, JE TI Demonstration of solar-generated electricity on demand: The Solar Two project SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article C1 Sandia Natl Labs, Concentrating Solar Power Dept, Albuquerque, NM 87185 USA. RP Pacheco, JE (reprint author), Sandia Natl Labs, Concentrating Solar Power Dept, POB 5800,MS 0703, Albuquerque, NM 87185 USA. NR 0 TC 11 Z9 11 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD FEB PY 2001 VL 123 IS 1 BP 5 EP 5 DI 10.1115/1.1341876 PG 1 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 407TR UT WOS:000167287300002 ER PT J AU Miller, WA Keyhani, M AF Miller, WA Keyhani, M TI The correlation of simultaneous heat and mass transfer experimental data for aqueous lithium bromide vertical falling film absorption SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID WAVY FILM; LIQUID-FILMS; WATER-VAPOR; FLOW AB A study of simultaneous heat and mass transfer was conducted on a vertical falling film absorber to better understand the mechanisms driving the heat and mass transfer processes. Thermographic phosphors were successfully used to measure the temperature profile along the length of the absorber test tube. These measures of the local variations in temperature enabled calculation of the bulk concentration along the length of the absorber The bulk concentration varied linearly which infers that the concentration gradient in the direction of flow is approximately constant. The implication is that the mass flux and therefore the absorber load can be solved for using a constant flux approximation. Design data and correlations are sparse in the open literature. Some experimental data are available; however, all literature data to date have been derived at mass fractions of lithium bromide ranging from 0.30 to 0.60, Experiments were therefore conducted with no heat and mass transfer additive on an internally cooled smooth tube of 0.01905-m outside diameter and of 1.53-m length. The data, for testing at 0.62 and 0.64 mass fraction. were scaled and correlated into both Nu and Sh formulations. The average absolute error in the Nu correlation is about +/-3.5% of the Nu number reduced from the experimental data. The Sh correlation is about +/-5% of the reduced Sh data. Data from the open literature were reduced to the authors Nu and Sh formulations, and were within 5% of the correlations developed in the present study. The study therefore provides test data with no heat and mass transfer additive and correlations for the coupled heat- and mass-transfer process that are validated against the extensive experimental data. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Mech & Aerosp Engn & Engn Sci Dept, Knoxville, TN 37996 USA. RP Miller, WA (reprint author), Oak Ridge Natl Lab, 1 Bethel Valley Rd,MS6070,Bldg 3147, Oak Ridge, TN 37831 USA. RI Keyhani, Majid/J-5387-2013 OI Keyhani, Majid/0000-0002-2845-9687 NR 27 TC 30 Z9 30 U1 3 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 FEB PY 2001 VL 123 IS 1 BP 30 EP 42 DI 10.1115/1.1349550 PG 13 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 407TR UT WOS:000167287300006 ER PT J AU Wong, TKY Kennedy, BJ Howard, CJ Hunter, BA Vogt, T AF Wong, TKY Kennedy, BJ Howard, CJ Hunter, BA Vogt, T TI Crystal structures and phase transitions in the SrTiO3-SrZrO3 solid solution SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID DIFFRACTION; PEROVSKITES AB Laboratory and synchrotron X-ray powder diffraction and neutron powder diffraction have been used to determine crystal structures in the perovskites SrTixZr1-xO3. Superlattice reflections in the neutron diffraction patterns proved to be the most reliable indicators of lower symmetry structures. The room temperature structures are orthorhombic Pbnm in the range of 0 less than or equal to x less than or equal to 0.4, tetragonal I4/mcm in the range 0.4 < x 0.95, and cubic Pm (3) over barm for 0.95 < x 1. Additional measurements were made on the room-temperature tetragonal samples at x = 0.5, 0.75, and 0.9, The first two were examined at elevated temperatures, using neutron diffraction methods, where the transition tetragonal to cubic was noted. Measurements at low temperatures using synchrotron X-ray powder diffraction are reported. (C) 2001 Academic Press. C1 Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Wong, TKY (reprint author), Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia. RI Howard, Christopher/B-5138-2009; Vogt, Thomas /A-1562-2011; OI Vogt, Thomas /0000-0002-4731-2787; Kennedy, Brendan/0000-0002-7187-4579 NR 24 TC 35 Z9 36 U1 2 U2 35 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD FEB 1 PY 2001 VL 156 IS 2 BP 255 EP 263 DI 10.1006/jssc.2000.8896 PG 9 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 407BR UT WOS:000167252000001 ER PT J AU Williford, RE Stevenson, JW Chou, SY Pederson, LR AF Williford, RE Stevenson, JW Chou, SY Pederson, LR TI Computer simulations of thermal expansion in lanthanum-based perovskites SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE lanthanum calcium chromite; lanthanum strontium cobalt iron oxide; free energy minimization; molecular dynamics; thermal expansion; partial charge models ID MOLECULAR-DYNAMICS; DEFECT CHEMISTRY; OXIDES; CHROMITE; RELEVANCE; BEHAVIOR; MN; CO AB Differential thermal expansion is important when two strongly bonded ceramics are subjected to high temperatures, as in solid oxide fuel cells. Free energy minimization (EM) and molecular dynamics (MD) techniques were used to simulate the thermal expansion of the perovskites (La,Ca)CrO3 and (La,Sr) (Co, Fe)O-3 on the atomistic scale. This paper explores the use of empirical partial charge interatomic potentials to represent the partially covalent bonding in these materials. The EM simulations underpredicted the thermal expansion coefficients (CTEs) by up to 26% due to limitations in the potentials. The MD simulations predicted the CTEs to within 17% of experimental data for (La,Ca)CrO3. MD predictions of the CTEs for (La,Sr)(Co,Fe)O-3 were significantly lower than the experimental data due to the approximate nature of the Co(4+)and Fe4+ interatomic potentials. Improvements in these results are possible if more extensive databases become available for refining the potentials and effective charges. (C) 2001 Academic Press. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Williford, RE (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 26 TC 5 Z9 5 U1 4 U2 11 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD FEB 1 PY 2001 VL 156 IS 2 BP 394 EP 399 DI 10.1006/jssc.2000.9011 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 407BR UT WOS:000167252000020 ER PT J AU Nicholson, WV Glaeser, RM AF Nicholson, WV Glaeser, RM TI Review: Automatic particle detection in electron microscopy SO JOURNAL OF STRUCTURAL BIOLOGY LA English DT Review DE electron microscopy; image processing; single-particle reconstruction; object detection; pattern recognition ID EDGE-DETECTION; BIOLOGICAL PARTICLES; PATTERN-RECOGNITION; CORRELATION FILTERS; CORRELATION PEAKS; MOMENT ANALYSIS; MICROGRAPHS; IMAGES; RESOLUTION; PHASE AB Advances in cryoEM and single-particle reconstruction have led to results at increasingly high resolutions. However, to sustain continuing improvements in resolution it will be necessary to increase the number of particles included in performing the reconstructions. Manual selection of particles, even when assisted by computer preselection, is a bottleneck that will become significant as single-particle reconstructions are scaled up to achieve near-atomic resolutions. This review describes various approaches that have been developed to address the problem of automatic particle selection. The principal conclusions that have been drawn from the results so far are: (1) cross-correlation with a reference image ("matched filtering") is an effective way to identify candidate particles, but it is inherently unable to avoid also selecting false particles; (2) false positives can be eliminated efficiently on the basis of estimates of particle size, density, and texture; (3) successful application of edge detection (or contouring) to particle identification may require improvements over currently available methods; and (4) neural network techniques, while computationally expensive, must also be investigated as a technology for eliminating false particles. (C) 2001 Academic Press. C1 Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Nicholson, WV (reprint author), Lawrence Berkeley Natl Lab, Phys Biosci Div, 1 Cyclotron Rd, Berkeley, CA 94720 USA. OI Nicholson, William/0000-0001-6614-0194 NR 62 TC 67 Z9 69 U1 1 U2 13 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1047-8477 J9 J STRUCT BIOL JI J. Struct. Biol. PD FEB-MAR PY 2001 VL 133 IS 2-3 BP 90 EP 101 DI 10.1006/jsbi.2001.4348 PG 12 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 457MU UT WOS:000170142000002 PM 11472081 ER PT J AU Jensen, GJ AF Jensen, GJ TI Alignment error envelopes for single particle analysis SO JOURNAL OF STRUCTURAL BIOLOGY LA English DT Article DE alignment; electron microscopy; envelope functions; image processing; resolution; single particle analysis ID RESOLUTION ELECTRON-MICROSCOPY; CONTRAST TRANSFER-FUNCTION; 3-DIMENSIONAL RECONSTRUCTION; ANGSTROM RESOLUTION; 400 KV; COHERENT ILLUMINATION; BIOLOGICAL MOLECULES; LOW-TEMPERATURE; ATOMIC MODEL; CCD CAMERA AB To determine the structure of a biological particle to high resolution by electron microscopy, image averaging is required to combine information from different views and to increase the signal-to-noise ratio. Starting from the number of noiseless views necessary to resolve features of a given size, four general factors are considered that increase the number of images actually needed: (1) the physics of electron scattering introduces shot noise, (2) thermal motion and particle inhomogeneity cause the scattered electrons to describe a mixture of structures, (3) the microscope system fails to usefully record all the information carried by the scattered electrons, and (4) image misalignment leads to information loss through incoherent averaging. The compound effect of factors 2-4 is approximated by the product of envelope functions. The problem of incoherent image averaging is developed in detail through derivation of five envelope functions that account for small errors in 11 "alignment" parameters describing particle location, orientation, defocus, magnification, and beam tilt. The analysis provides target error tolerances for single particle analysis to near-atomic (3.5 Angstrom) resolution, and this prospect is shown to depend critically on image quality, defocus determination, and microscope alignment. (C) 2001 Academic Press. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Jensen, GJ (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [GM07365] NR 51 TC 25 Z9 25 U1 0 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1047-8477 J9 J STRUCT BIOL JI J. Struct. Biol. PD FEB-MAR PY 2001 VL 133 IS 2-3 BP 143 EP 155 DI 10.1006/jsbi.2001.4334 PG 13 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 457MU UT WOS:000170142000007 PM 11472086 ER PT J AU Ghim, YS Oh, HS Chang, YS AF Ghim, YS Oh, HS Chang, YS TI Meteorological effects on the evolution of high ozone episodes in the greater seoul area SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID POLLUTION EPISODES AB Three high O-3 episodes-7 days in 1992 (July 3-July 9), 9 days in 1994 (July 21-July 29), and another 3 days in 1994 (August 22-August 24)-were selected on the basis of morning (7:00 a.m.-10:00 a.m.) average wind direction and speed and daily maximum O-3 concentrations in the greater Seoul, Korea, of 1990-1997. To better understand their characteristics and life cycles, surface data from the Seoul Weather Station (SWS) and surface and 850-hPa wind field data covering northeast Asia around the Korean Peninsula were used for the analysis. In the July 1992 episode, westerly winds were most frequent as a result of the influence of a high-pressure system west of the Korean Peninsula behind a trough. In contrast, in the July 1994 episode, easterly winds were most frequent as a result of the effect of a typhoon moving north from the south of Japan. Despite different prevailing wind directions, the peak O-3 concentrations for each episode occurred when a sea/land breeze developed in association with weak synoptic forcing. The August 1994 episode, which was selected as being representative of calm conditions, was another typical example in which a well-developed sea/land breeze helped cause the peak O-3 concentration to rise to a record high of 322 parts per billion by volume (ppbv). All three high O-3 episodes ended as a result of precipitation, and subsequent rises in O-3 concentrations were also suppressed by a series of precipitation events afterwards. In particular, two heavy rainfalls were the main reason why the August 1994 episode, which had the highest and second-highest O-3 concentrations, lasted only a few days. C1 Korea Inst Sci & Technol, Global Environm Res Ctr, Seoul 130650, South Korea. Argonne Natl Lab, Environm Assessment Div, Argonne, IL 60439 USA. RP Ghim, YS (reprint author), POB 131, Seoul 130650, South Korea. NR 33 TC 22 Z9 22 U1 0 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 FEB PY 2001 VL 51 IS 2 BP 185 EP 202 PG 18 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 402ED UT WOS:000166972300003 PM 11256497 ER PT J AU Cadle, SH Gorse, RA Bailey, BK Lawson, DR AF Cadle, SH Gorse, RA Bailey, BK Lawson, DR TI Real-world vehicle emissions: A summary of the tenth coordinating research council on-road vehicle emissions workshop SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article AB The Coordinating Research Council (CRC) held its tenth workshop in March 2000, focusing on results from the most recent real-world vehicle emissions research. In this paper, we summarize the presentations from researchers who are engaged in improving our understanding of the contribution of mobile sources to emission inventories. Participants in the workshop discussed efforts to improve mobile source emission models and emission inventories, results from gas- and particle-phase emissions studies from spark-ignition and diesel-powered vehicles, new methods for measuring mobile source emissions, improvements in vehicle emission control systems (ECSs), and evaluation of motor vehicle inspection/maintenance (I/M) programs, as well as topics for future research. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. GM Corp, Ctr Res & Dev, Warren, MI USA. Ford Motor Co, Allen Park, MI USA. Coordinating Res Council, Alpharetta, GA USA. RP Lawson, DR (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 0 TC 2 Z9 2 U1 0 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 FEB PY 2001 VL 51 IS 2 BP 236 EP 249 PG 14 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 402ED UT WOS:000166972300006 PM 11256499 ER PT J AU Paranthaman, MP Chirayil, TG List, FA Cui, XT Goyal, A Lee, DF Specht, ED Martin, PM Williams, RK Kroeger, DM Morrell, JS Beach, DB Feenstra, R Christen, DK AF Paranthaman, MP Chirayil, TG List, FA Cui, XT Goyal, A Lee, DF Specht, ED Martin, PM Williams, RK Kroeger, DM Morrell, JS Beach, DB Feenstra, R Christen, DK TI Fabrication of long lengths of epitaxial buffer layers on biaxially textured nickel substrates using a continuous reel-to-reel dip-coating unit SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CRITICAL-CURRENT DENSITY; SOL-GEL SYNTHESIS; THIN-FILMS; SUPERCONDUCTING FILMS; ALUMINATE FILMS; GROWTH; DEPOSITION; PRECURSORS; LAALO3; TAPES AB A low-cost, nonvacuum, solution precursor route has been developed to produce epitaxial oxide buffer layers of Eu2O3 or La2Zr2O7 on biaxially textured Ni (100) tapes. A reel-to-reel continuous dip-coating unit consisting of a constant-tension tape transport system attached to a controlled atmosphere furnace was fabricated. Nickel tapes were pulled through a 2-methoxyethanol solution of europium methoxyethoxide/acetate or lanthanum zirconium methoxyethoxide. The double-sided dip coated tapes were then annealed in a preheated furnace at 1000 degrees -1100 degreesC with a high flow rate of Ar/H-2 (4%) gas. The dip-coated buffers were dense, continuous, crack-free, and epitaxial with a single cube texture. A critical current (J(c)) of >1 MA/cm(2) at 77 K and self-field was obtained for YBa2Cu3O7-delta (YBCO) films with a layer sequence of YBCO (ex situ BaF2 process)/CeO2 (sputtered)/YSZ (sputtered)/Eu2O3 (dip-coated)/nickel, We have produced 1-2 m lengths of epitaxial buffer layers on textured nickel substrates using a nonvacuum process for the first time. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Paranthaman, MP (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Specht, Eliot/A-5654-2009; Paranthaman, Mariappan/N-3866-2015 OI Specht, Eliot/0000-0002-3191-2163; Paranthaman, Mariappan/0000-0003-3009-8531 NR 24 TC 35 Z9 37 U1 0 U2 6 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 FEB PY 2001 VL 84 IS 2 BP 273 EP 278 PG 6 WC Materials Science, Ceramics SC Materials Science GA 402EF UT WOS:000166972500003 ER PT J AU Rush, BM Reimer, JA Cairns, EJ AF Rush, BM Reimer, JA Cairns, EJ TI Nuclear magnetic resonance and voltammetry studies of carbon monoxide adsorption and oxidation on a carbon-supported platinum fuel cell electrocatalyst SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID REFLECTION ABSORPTION-SPECTROSCOPY; LOW-INDEX PLATINUM; SULFURIC-ACID; CO; ELECTRODE; NMR; PT(111); STATES; REGION AB Nuclear magnetic resonance (NMR) spectroscopy has been used in conjunction with voltammetry to investigate the mechanism for the electrocatalytic oxidation of CO on a carbon-supported PC fuel cell electrocatalyst in 2 M H2SO4 at ambient temperature. The states of adsorbed CO(COads), the conditions which give rise to them, and their oxidation pathways were investigated as a function of COads coverage and the working electrode potential of adsorption (E-ads). CO was adsorbed from the electrolyte at various fixed values of E-ads between 0 and 600 mV vs. RHE. Submonolayer coverages of COads were formed in two different ways, by adsorption for limited amounts of time and by partial oxidation of an initially saturated coverage. The COads coverage was then characterized via voltammetric oxidation and via C-13 NMR. Voltammetry data were analyzed qualitatively in terms of the number, shape, and position of COads oxidation peaks and quantitatively in terms of the total charge required to oxidize the COads coverage and the total number of catalyst sites occupied by the COads. NMR spectra were analyzed qualitatively in terms of their lineshape and position and quantitatively in terms of their integrated intensity. These results have been utilized in the formulation of an overall model for the adsorption and oxidation of CO on Pt in an acid electrolyte at ambient temperature. Three distinct forms of COads are identified on the Pt electrocatalyst, a linear carbonyl, a bridged carbonyl, and a reduced carbonyl (a hydrogenated carbonyl requiring a three-electron transfer for complete oxidation to CO2). The relative populations of these three species are found to depend strongly on E-ads and to be substantially independent of coverage. Different oxidation behaviors are observed for different populations of the three COads species, suggesting that different oxidation reaction pathways are associated with the three COads states. (C) 2001 The Electrochemical Society. All rights reserved. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Rush, BM (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 34 TC 36 Z9 36 U1 2 U2 11 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 FEB PY 2001 VL 148 IS 2 BP A137 EP A148 DI 10.1149/1.1342164 PG 12 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 404ME UT WOS:000167103100004 ER PT J AU Allendorf, MD Spear, KE AF Allendorf, MD Spear, KE TI Thermodynamic analysis of silica refractory corrosion in glass-melting furnaces SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SOLID ELECTROLYTE; NA2O-SIO2 MELTS; BETA-ALUMINA; NA2O; EQUILIBRIA; K2O-SIO2; SYSTEMS AB Corrosion of refractory silica brick used to line the roof or "crown" of many glass-melting furnaces is a serious problem in furnaces using oxygen-fuel rather than air-fuel mixtures. In this work, we report equilibrium calculations that support a corrosion mechanism in which alkali hydroxide gas (NaOH or KOH), produced by reaction of water vapor in the combustion eas with the molten glass, reacts with the silica brick in the furnace crown to produce an alkali silicate liquid with a composition;hat depends on the temperature of the crown. Our reported calculations predict the variable-composition liquid-solution corrosion product phase as a function of key furnace variables. Critical thermodynamic data needed for the liquid corrosion product were generated using a modified associate species solution model and critical analysis of thermochemical information found in the literature for the Na2O-SiO2 and K2O-SiO2 systems. Excellent agreement with reported Na2O-SiO2 and K2O-SiO2 phase diagrams and with experimentally measured activities for Na2O and K2O is achieved. The results of our current calculations are for temperatures between 1273 and 1973 K (1000-1700 degreesC) under either air-fired or oxy-fired conditions, and are used to define a "critical temperature," above which corrosion is not expected to occur for a given NaOH(g) or KOH(g) partial pressure. (C) 2001 The Electrochemical Society. All rights reserved. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. RP Allendorf, MD (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 29 TC 42 Z9 42 U1 2 U2 11 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 FEB PY 2001 VL 148 IS 2 BP B59 EP B67 DI 10.1149/1.1337603 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 404ME UT WOS:000167103100009 ER PT J AU Yu, SY Scully, JR Vitus, CM AF Yu, SY Scully, JR Vitus, CM TI Influence of niobium and zirconium alloying additions on the anodic dissolution behavior of activated titanium in HCl solutions SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID AQUEOUS CHLORIDE SOLUTIONS; CORROSION-RESISTANCE; PITTING CORROSION; VALVE METALS; OXIDE-FILMS; FE-CR; PASSIVATION; ELECTROCHEMISTRY; ELEMENTS; BREAKDOWN AB Ti-45 wt % Nb (30 atom % Nb), and Ti-50 wt % Zr (34.4 atom % Zr), with the alloying elements in solid solution, exhibited reduced active anodic dissolution rates in comparison with commercially pure titanium (C. P. Ti) in deaerated hydrochloric acid (HCl) at 37 degreesC. Furthermore, the alloying additions of niobium (Nb) and zirconium (Zr) to Ti were shown to reduce the anodic charge density required to transition from active anodic dissolution to passivity. The improved resistance of Ti-45% Nb, and Ti-50% Zr to active anodic dissolution in comparison to Ti was not attributable to spontaneous passivity induced by enhanced cathodic kinetics, as in Ti alloys containing noble metals, such as palladium. Instead, improved active dissolution resistance is attributed to strong covalent bond formation between neighboring Ti, Nbi and Zr atoms through the sharing of unpaired d level electrons. The extent of increases in covalent bond strengths is quantified by comparing the bond orders between atoms. A relationship between i(crit), i(corr), and bond order of selected Ti-based alloys is presented. The correlation obtained here takes into consideration surface enrichment of the Ti alloy surfaces with Nb and, possibly, Zr due to the preferential dissolution of Ti in the active state. (C) 2001 The Electrochemical Society. All rights reserved. C1 Univ Virginia, Ctr Electrochem Sci & Engn, Charlottesville, VA 22903 USA. Brookhaven Natl Lab, Dept Appl Sci, Div Mat Sci, Upton, NY 11973 USA. RP Yu, SY (reprint author), Univ Virginia, Ctr Electrochem Sci & Engn, Charlottesville, VA 22903 USA. NR 47 TC 33 Z9 33 U1 4 U2 17 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 FEB PY 2001 VL 148 IS 2 BP B68 EP B78 DI 10.1149/1.1337605 PG 11 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 404ME UT WOS:000167103100010 ER PT J AU Stefan, IC Tolmachev, YV Nagy, Z Minkoff, M Merrill, DR Mortimer, JT Scherson, DA AF Stefan, IC Tolmachev, YV Nagy, Z Minkoff, M Merrill, DR Mortimer, JT Scherson, DA TI Theoretical analysis of the pulse-clamp method as applied to neural stimulating electrodes SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID DENSITY-OVERPOTENTIAL RANGE; APPLICABILITY AB A mathematical model was developed to simulate potential pulse clamp experiments at inert-electrode/aqueous solution interfaces in the absence of dioxygen or other adventitious redox active species. This model incorporates a potential invariant interfacial capacitor, a kinetically slow redox couple with parameters consistent with the H2O/H-2 reaction on polycrystalline Au in acid electrolytes as the only faradaic process involved, and diffusion as the only mode of mass transport in solution phase. Numerical integration of the resulting system of differential equations was found to yield results in good agreement with experimental data reported by Mortimer and co-workers for Au in dearated sulfuric acid solutions. A detailed analysis of these calculations identified the fast and slow recoverable charges to be capacitive and the unrecoverable charges to be faradaic. The results obtained indicated that for small overpotentials the charge is stored in the interfacial capacitor, and that significant faradaic processes occur only when the overpotential is large. Furthermore, during the delay, and despite the fact that no current flows through the external circuit, the capacitor discharges via the faradaic reaction, increasing the total amount of product generated. More importantly, under the conditions selected for the simulations, none of the faradaic charge is recovered during the potential controlled stage of the sequence. These results provide insight into the relationships between stimulus parameters and charge injected into irreversible faradaic reactions, which may generate biologically harmful species. In general, as stimulus pulse durations increase, unrecoverable charge increases. Also, as the delay increases between the end of the primary and beginning of the secondary pulse, unrecoverable. charge increases. Furthermore, based on the mathematical model used herein, the use of an electrode material with a small exchange current density would allow greater overpotentials to be reached before the onset of significant faradaic reactions, and thus greater total charge injection prior to faradaic reactions. (C) 2001 The Electrochemical Society. All rights reserved. C1 Case Western Reserve Univ, Dept Chem, Cleveland, OH 44106 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Case Western Reserve Univ, Appl Neural Control Lab, Cleveland, OH 44106 USA. RP Stefan, IC (reprint author), Case Western Reserve Univ, Dept Chem, Cleveland, OH 44106 USA. OI Tolmachev, Yuriy/0000-0001-6705-6058 NR 10 TC 4 Z9 4 U1 1 U2 2 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD FEB PY 2001 VL 148 IS 2 BP E73 EP E78 DI 10.1149/1.1341236 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 404ME UT WOS:000167103100029 ER PT J AU de Arellano-Lopez, AR Lopez-Pombero, S Dominguez-Rodriguez, A Routbort, JL Singh, D Goretta, KC AF de Arellano-Lopez, AR Lopez-Pombero, S Dominguez-Rodriguez, A Routbort, JL Singh, D Goretta, KC TI Plastic deformation of silicon nitride/boron nitride fibrous monoliths SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article DE creep; BN; fibrous monoliths; mechanical properties; Si3N4 ID GRAIN-BOUNDARY PHASE; BORON-NITRIDE; CREEP; CERAMICS; MICROSTRUCTURE; FRACTURE AB High-temperature compressive creep of unidirectional Si3N4/BN fibrous monoliths has been investigated at 1300-1500 degreesC in an inert atmosphere. The results were then compared to those for deformation of the Si3N4 and BN base materials. Plasticity of the fibrous monoliths was limited to very low stresses when the Si3N4 cells were oriented perpendicular to the stress axis because the BN cell boundaries failed, followed by failure of the Si3N4 cells. In the fibrous monolith in which cells were oriented parallel to the stress axis, steady-state deformation controlled by deformation of the Si3N4 cells was achieved. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Sevilla, Dept Fis Mat Condensada, E-41080 Seville, Spain. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60349 USA. RP de Arellano-Lopez, AR (reprint author), Univ Sevilla, Dept Fis Mat Condensada, POB 1065, E-41080 Seville, Spain. OI R. de Arellano Lopez, Antonio/0000-0002-7443-0244; Dominguez-Rodriguez, Arturo/0000-0003-1598-5669 NR 25 TC 8 Z9 8 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0955-2219 J9 J EUR CERAM SOC JI J. European Ceram. Soc. PD FEB PY 2001 VL 21 IS 2 BP 245 EP 250 DI 10.1016/S0955-2219(00)00175-8 PG 6 WC Materials Science, Ceramics SC Materials Science GA 394YE UT WOS:000166551300017 ER PT J AU Sheehy, B Clatterbuck, TO Lyng, C Martin, JDD Kim, DW DiMauro, LF Gaarde, MB Schafer, KJ Agostini, P Kulander, KC AF Sheehy, B Clatterbuck, TO Lyng, C Martin, JDD Kim, DW DiMauro, LF Gaarde, MB Schafer, KJ Agostini, P Kulander, KC TI Strong field physics in a scaled interaction SO LASER PHYSICS LA English DT Article; Proceedings Paper CT 9th Annual International Laser Physics Workshop (LPHYS 2000) CY JUL 17-21, 2000 CL BORDEAUX, FRANCE ID HIGH HARMONIC-GENERATION; RARE-GASES; IONIZATION; PULSES; RADIATION; ATOMS; PHASE AB Strong-field interactions at long wavelengths are studied experimentally and theoretically, and compared with studies at shorter wavelengths. Under similar dynamical conditions, we find a more pronounced role for atomic structure in the long wavelength studies. Ion core structure is reflected in photoelectron energy spectra in a manner consistent with the rescattering picture, and stronger coupling between ground and excited states influences high harmonic generation spectra. Spectral and temporal measurements of high harmonics generated from a mid-infrared fundamental are presented. C1 Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RIST, Dept Phys, Pohang, South Korea. Lund Inst Technol, S-22100 Lund, Sweden. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Ctr Etud Saclay, SPAM, F-91191 Gif Sur Yvette, France. Lawrence Livermore Natl Lab, V Div, Livermore, CA 94551 USA. RP Sheehy, B (reprint author), Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. EM sheehy@bnl.gov NR 19 TC 3 Z9 3 U1 0 U2 0 PU MAIK NAUKA/INTERPERIODICA/SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013-1578 USA SN 1054-660X J9 LASER PHYS JI Laser Phys. PD FEB PY 2001 VL 11 IS 2 BP 226 EP 230 PG 5 WC Optics; Physics, Applied SC Optics; Physics GA 407MJ UT WOS:000167275100011 ER PT J AU Smyser, C Grabowski, TJ Frank, RJ Haller, JW Bolinger, L AF Smyser, C Grabowski, TJ Frank, RJ Haller, JW Bolinger, L TI Real-time multiple linear regression for fMRI supported by time-aware acquisition and processing SO MAGNETIC RESONANCE IN MEDICINE LA English DT Article DE fMRI; real-time; multiple linear regression; brain mapping ID FUNCTIONAL MRI; RETROSPECTIVE ESTIMATION; ACTIVATION; PARADIGM AB Real-time parametric statistical analysis of functional MRI (fMRI) data would potentially enlarge the scope of experimentation and facilitate its application to clinical populations. A system is described that addresses the need for rapid analysis of fMRI data and lays the foundation for dealing with problems that impede the application of fMRI to clinical populations. The system, I/OWA (Input/Output time-aWare Architecture), combines a general architecture for sampling and time-stamping relevant information channels in fMRI (image acquisition, stimulation, subject responses, cardiac and respiratory monitors, etc.) and an efficient approach to manipulating these data, featuring incremental subsecond multiple linear regression. The advantages of the system are the simplification of event timing and efficient and unified data formatting, Substantial parametric analysis can be performed and displayed in realtime. Immediate (replay) and delayed off-line analysis can also be performed with the same interface. The capabilities of the system are demonstrated in normal subjects using a polar visual angle phase mapping paradigm. The system provides a time-accounting infrastructure that readily supports standard and innovative approaches to fMRI, Magn Reson Med 45: 289-298, 2001, (C) 2001 Wiley-Liss, Inc. C1 Univ Iowa, Dept Neurol, Iowa City, IA 52242 USA. Univ Iowa, Dept Radiol, Iowa City, IA 52242 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Iowa, Dept Biomed Engn, Iowa City, IA 52242 USA. RP Grabowski, TJ (reprint author), Univ Iowa Hosp & Clin, Dept Neurol, 200 Hawkins Dr, Iowa City, IA 52242 USA. NR 27 TC 28 Z9 28 U1 1 U2 3 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0740-3194 J9 MAGNET RESON MED JI Magn. Reson. Med. PD FEB PY 2001 VL 45 IS 2 BP 289 EP 298 DI 10.1002/1522-2594(200102)45:2<289::AID-MRM1038>3.0.CO;2-U PG 10 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 397WF UT WOS:000166720300016 PM 11180437 ER PT J AU Tomasko, D Williams, GP Smith, K AF Tomasko, D Williams, GP Smith, K TI An analytical model for simulating step-function injection in a radial geometry SO MATHEMATICAL GEOLOGY LA English DT Article DE radial injection; numerical Laplace inversion; Crump algorithm ID NUMERICAL INVERSION; LAPLACE TRANSFORMS; DISPERSION PROBLEM AB An analytical model is developed for analyzing underground injection of wastes that undergo advection, dispersion, sorption, and first-order degradation. The model uses a time-dependent, step function source that simulates intermittent waste injection in a continuous fluid injection well. The governing equations for a cylindrically symmetrical system (ire cast in nondimensional form and then transformed and solved in Laplace,space. The Laplace space solution is inverted with the Crump algorithm, which uses the real and imaginary parts of a Fourier series. The numerical solution is verified by replicating the step function source at the point of injection, and the behavior of the model is demonstrated in a series of figures. The model is recommended for quick. scoping calculations in which there is little site-specific information and periods of discontinuous radial injection. C1 Argonne Natl Lab, Environm Assessment Div, Argonne, IL 60439 USA. RP Williams, GP (reprint author), Argonne Natl Lab, Environm Assessment Div, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Williams, Gustavious/P-7252-2014 OI Williams, Gustavious/0000-0002-2781-0738 NR 21 TC 6 Z9 6 U1 0 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0882-8121 J9 MATH GEOL JI Math. Geol. PD FEB PY 2001 VL 33 IS 2 BP 155 EP 165 DI 10.1023/A:1007531201061 PG 11 WC Geosciences, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Geology; Mathematics GA 489NC UT WOS:000171996800003 ER PT J AU Wang, SD Lee, SB Hsueh, CH AF Wang, SD Lee, SB Hsueh, CH TI Effect of substrate modulus difference on dislocation formation in an epitaxial film SO MECHANICS OF MATERIALS LA English DT Article DE epitaxial film; substrate; dislocation; critical thickness ID MISFIT DISLOCATIONS; CRITICAL THICKNESS; ENERGY; EPILAYER; LAYER; ARRAY AB The effect of substrate modulus difference on dislocation formation in an epitaxial film is derived in the present study. The analysis is based on the energy approach, in which the self-energy of the dislocation and the interaction energy between the dislocation and the mismatch strain are calculated. The elastic stress field due to the interface dislocation is derived by superposition of the elastic stress fields of the film/substrate system with the following two configurations: (i) a dislocation at the interface assuming the film is also semi-infinite, and (ii) prescribed traction on the film surface which are the negative of those calculated from the first configuration at the location equivalent to the film surface in the second configuration. The results show that the critical film thickness for forming interface dislocation increases with the decrease in the shear modulus ratio of the film to the substrate. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Natl Tsing Hua Univ, Dept Mat Sci & Engn, Hsinchu 30013, Taiwan. Chung Chou Jr Coll Technol & Commerce, Dept Mech Engn, Changhua, Taiwan. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Lee, SB (reprint author), Natl Tsing Hua Univ, Dept Mat Sci & Engn, 101,Sec 2,Kuang Fu Rd, Hsinchu 30013, Taiwan. RI Hsueh, Chun-Hway/G-1345-2011 NR 17 TC 3 Z9 3 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6636 J9 MECH MATER JI Mech. Mater. PD FEB PY 2001 VL 33 IS 2 BP 105 EP 120 DI 10.1016/S0167-6636(00)00058-2 PG 16 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA 404CF UT WOS:000167079300005 ER PT J AU Davies, RW Grant, GJ Oliver, HE Khaleel, MA Smith, MT AF Davies, RW Grant, GJ Oliver, HE Khaleel, MA Smith, MT TI Forming-limit diagrams of aluminum tailor-welded blank weld material SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID SHEET AB The current work develops forming-limit diagrams (FLDs) for weld materials in aluminum tailor-welded blanks (TWBs) under biaxial stretching conditions. Aluminum TWBs consist of multiple-thickness and alloy sheet materials welded together into a single, variable-thickness blank. The manufacture of TWBs and their application in automotive body panels requires their constituent weld material to deform under biaxial loading during sheet-metal stamping. The weld geometry is typically nonuniform and relatively small, causing difficulty if one attempts to determine the weld metal FLDs via traditional experimental methods. The subject work primarily relies on theoretical FLD calculation techniques using the Marciniak and Kuczynski (M-K) method. This numerical technique requires the use of material constants and levels of initial material imperfection that have been experimentally determined using unique miniature tensile specimens to isolate and characterize the weld metal. The experimental and numerical work, together with statistical analysis of the level of initial imperfection, allows generation of both an average and safe FLD. The weld metals studied in this work were produced via autogeneous gas tungsten are welding of a 1- to 2-mm-thick 5000 series aluminum alloy sheet. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Reynolds Met Co, Prod Engn & Technol, Chester, VA USA. RP Davies, RW (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. OI khaleel, mohammad/0000-0001-7048-0749 NR 18 TC 30 Z9 34 U1 6 U2 13 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD FEB PY 2001 VL 32 IS 2 BP 275 EP 283 DI 10.1007/s11661-001-0259-7 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 398VK UT WOS:000166777000009 ER PT J AU Susan, DF Misiolek, WZ Marder, AR AF Susan, DF Misiolek, WZ Marder, AR TI Reaction synthesis of Ni-Al-based particle composite coatings SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID NICKEL ALUMINIDES; RESISTANCE; COMBUSTION; NI3AL; BATH AB Electrodeposited metal matrix/metal particle composite (EMMC) coatings were produced with a nickel matrix and aluminum particles. By optimizing the process parameters, coatings were deposited with 20 vol pct aluminum particles. Coating morphology and composition were characterized using light optical microscopy (LOM), scanning electron microscopy (SEM), and electron probe microanalysis (EPMA). Differential thermal analysis (DTA) was employed to study reactive phase formation. The effect of heat treatment on coating phase formation was studied in the temperature range 415 degreesC to 1000 degreesC. Long-time exposure at low temperature results in the formation of several intermetallic phases at the Ni matrix/Al particle interfaces and concentrically around the original Al particles. Upon heating to the 500 degreesC to 600 degreesC range, the aluminum particles react with the nickel matrix to form NiAl islands within the Ni matrix. When exposed to higher temperatures (600 degreesC to 1000 degreesC), diffusional reaction between NiAl and nickel produces (gamma')Ni3Al. The final equilibrium microstructure consists of blocks of (gamma')Ni3Al in a gamma (Ni) solid solution matrix, with small pores also present. Pore formation is explained based on local density changes during intermetallic phase formation, and microstructural development is discussed with reference to reaction synthesis of bulk nickel aluminides. C1 Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. Sandia Natl Labs, Mat Characterizat Dept, Albuquerque, NM 87185 USA. RP Susan, DF (reprint author), Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. NR 33 TC 29 Z9 33 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD FEB PY 2001 VL 32 IS 2 BP 379 EP 390 DI 10.1007/s11661-001-0269-5 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 398VK UT WOS:000166777000019 ER PT J AU Rosenberg, ND Browning, L Bourcier, WL AF Rosenberg, ND Browning, L Bourcier, WL TI Modeling aqueous alteration of CM carbonaceous chondrites SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID THERMAL EVOLUTION; PARENT BODIES; ASTEROIDS; GEOCHEMISTRY; MINERALOGY; INDICATORS; WATER; BELT AB Results from an inorganic geochemical modeling study support a scenario in which low-temperature aqueous alteration of an anhydrous CM asteroidal parent body and melt water from H2O and CO2 ices produces the altered assemblage observed in CM carbonaceous chondrites (chrysotile, greenalite, tochilinite, cronstedtite and minor calcite and magnetite). We consider a range of possible precursor mineral assemblages, varying with respect to the Fe-oxidation state of the initial anhydrous phases. The aqueous solutions produced by this alteration are generally strongly basic and reducing and a large quantity of H-2, and possible CH4, gas can be released during aqueous alteration. C1 Univ Calif Lawrence Livermore Natl Lab, Earth & Environm Sci Directorate, Livermore, CA 94551 USA. SW Res Inst, Ctr Nucl Waste Regulatory Anal, San Antonio, TX 78238 USA. RP Rosenberg, ND (reprint author), Univ Calif Lawrence Livermore Natl Lab, Earth & Environm Sci Directorate, Livermore, CA 94551 USA. NR 33 TC 38 Z9 38 U1 1 U2 7 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD FEB PY 2001 VL 36 IS 2 BP 239 EP 244 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 414EK UT WOS:000167652800007 ER PT J AU Welten, KC Nishiizumi, K Masarik, J Caffee, MW Jull, AJT Klandrud, SE Wieler, R AF Welten, KC Nishiizumi, K Masarik, J Caffee, MW Jull, AJT Klandrud, SE Wieler, R TI Cosmic-ray exposure history of two Frontier Mountain H-chondrite showers from spallation and neutron-capture products SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID NON-ANTARCTIC METEORITES; COSMOGENIC NUCLIDES; PRODUCTION-RATES; IRON-METEORITES; CL-36; CA-41; AMS; STONY; AGES; DISTRIBUTIONS AB We measured the concentrations of Be-10, Al-26, Cl-36, Ca-41 and C-14 in the metal and/or stone fractions of 27 Antarctic chondrites from Frontier Mountain (FRO), including two large H-chondrite showers. To estimate the pre-atmospheric size of the two showers, we determined the contribution of neutron-capture produced Cl-36 (half-lift: = 3.01 x 10(5) years) and Ca-41(1.04 x 10(5) years) in the stone fraction. The measured activities of neutron-capture Cl-36 and 41Ca, as well as spallation produced Be-10 and Al-26, were compared with Monte Carlo-based model calculations. The largest shower, FRO 90174, includes eight fragments with an average terrestrial age of(100 +/- 30) x 10(3) years; the neutron-capture saturation activities extend to 27 dpm/kg stone for Cl-36 and 19 dpm/kg stone for 41Ca. The concentrations of spallation produced Be-10, Al-26 and Cl-36 constrain the radius (R) to 80-100 cm, while the neutron-capture Ca-41 activities indicate that the samples originated from the outer 25 cm. With a pre-atmospheric radius of 80-100 cm, FRO 90174 is among the largest of the Antarctic stony meteorites. The large pre-atmospheric size supports our hypothesis that at least 50 of the similar to 150 classified H5/H6-chondrites from the Frontier Mountain stranding area belong to this single fall; this hypothesis does not entirely account for the high H/L ratio at Frontier Mountain. The smaller shower, FRO 90001, includes four fragments with an average terrestrial age of (40 +/- 10) x 10(3) years; they contain small contributions of neutron-capture Cl-36, but no excess of Ca-41. FRO 90001 experienced a complex exposure history with high shielding conditions in the first stage (150 < R < 300 cm) and much lower shielding in the second stage (R < 30 cm), the latter starting 1.0 million years (Ma) ago. Based on the measured Be-10/Ne-21 and Al-26/Ne-21 ratios, the cosmic-ray exposure ages of the two showers are 7.2 +/- 0.5 Ma for FRO 90174 and 8 +/- 1 Ma for FRO 90001. These ages coincide with the well-established H-chondrite peak and corroborate the observation that the exposure age distribution of FRO H-chondrites is similar to that of non-Antarctic falls. In addition, we found that corrections for neutron-capture Ar-36 (from decay of Cl-36) result in concordant Ne-21 and Ar-38 exposure ages. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Geosci & Environm Technol Div, Livermore, CA 94550 USA. Univ Arizona, NSF Arizona AMS Lab, Tucson, AZ 85721 USA. ETH Zurich, CH-8092 Zurich, Switzerland. RP Welten, KC (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RI Wieler, Rainer/A-1355-2010; Caffee, Marc/K-7025-2015 OI Wieler, Rainer/0000-0001-5666-7494; Caffee, Marc/0000-0002-6846-8967 NR 47 TC 41 Z9 41 U1 0 U2 5 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD FEB PY 2001 VL 36 IS 2 BP 301 EP 317 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 414EK UT WOS:000167652800011 ER PT J AU Roy, AK Spragge, MK Fleming, DL Lum, BY AF Roy, AK Spragge, MK Fleming, DL Lum, BY TI Cracking of titanium alloys under cathodic applied potential SO MICRON LA English DT Review DE stress corrosion cracking; hydrogen embrittlement; titanium alloys; slow-strain-rate test; controlled potential ID EMBRITTLEMENT; HYDROGEN AB The slow-strain-rate test technique was used to evaluate the susceptibility of Ti Gr-7 and Ti Gr-12 to hydrogen-induced-cracking and/or stress corrosion cracking. Ti Gr-7 and Ti Gr-12 are two candidate container materials for the multi-barrier package for nuclear waste. The tests were done in a deaerated 90 degrees C acidic brine (pH approximate to 2.7) containing 5 weight percent (wt.%) NaCl using a strain rate of 3.3 x 10(-6) s(-1) Before being tested in the acidic brine, specimens of each alloy were pulled inside the test chamber in the dry condition at ambient temperature. Then, while in the test solution, specimens were strained under different cathodic controlled potentials. These controlled potentials were selected based on the corrosion potential measured in the test solution before the specimens were strained. Results indicate that the times to failure (TTF) for Ti Gr-12 were much shorter than those for Ti Gr-7. Furthermore, as the applied potential became more cathodic, Ti Gr-12 showed reduced ductility in terms of percent reduction in area and true fracture stress (sigma(f)) In addition, the TTF and percent elongation reached the minimum values when Ti Gr-12 was tested under an impressed potential of -1162 mV. However, for Ti Gr-7, all these ductility parameters were not significantly influenced by the changes in applied potential. In general, the results of hydrogen analysis by secondary ion mass spectrometry showed increased hydrogen concentration at more cathodic controlled potentials. Optical microscopy and scanning electron microscopy were used to evaluate the morphology of cracking both at the primary fracture face and the secondary cracks along the gage section of the broken tensile specimen. Transgranular secondary cracks were observed in both alloys possibly resulting from the formation of brittle titanium hydrides due to cathodic charging. The primary fracture face was characterized by dimpled microstructure indicating ductile failure. Published by Elsevier Science. C1 Univ Calif Lawrence Livermore Natl Lab, Framatome Cogema Fuels, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Roy, AK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Framatome Cogema Fuels, 7000 East Ave,M-S L-631, Livermore, CA 94550 USA. NR 11 TC 4 Z9 5 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0968-4328 J9 MICRON JI Micron PD FEB PY 2001 VL 32 IS 2 BP 211 EP 218 DI 10.1016/S0968-4328(99)00104-3 PG 8 WC Microscopy SC Microscopy GA 355BP UT WOS:000089366000012 ER PT J AU Campos, A Zhang, RG Alkire, RW Matsumura, P Westbrook, EM AF Campos, A Zhang, RG Alkire, RW Matsumura, P Westbrook, EM TI Crystal structure of the global regulator FlhD from Escherichia coli at 1.8 angstrom resolution SO MOLECULAR MICROBIOLOGY LA English DT Article ID IMAGING PROPORTIONAL COUNTER; PROTEIN-PROTEIN INTERACTIONS; DISULFIDE BOND FORMATION; DNA-BINDING DOMAINS; TRANSCRIPTIONAL ACTIVATOR; ANOMALOUS DIFFRACTION; CELL-DIVISION; CYTOPLASM; CRYSTALLOGRAPHY; PRINCIPLES AB FlhD is a 13.3 kDa transcriptional activator protein of flagellar genes and a global regulator. FlhD activates the transcription of class II operons in the flagellar regulon when complexed with a second protein FlhC (21.5 kDa). FlhD also regulates other expression systems in Escherichia coli. We are seeking to understand this plasticity of FlhD's DNA-binding specificity and, to this end, we have determined the crystal structure of the isolated FlhD protein. The structure was solved by substituting seleno-methionine for natural sulphur-methionine in FlhD, crystallizing the protein and determining the structure factor phases by the method of multiple-energy anomalous dispersion (MAD). The FlhD protein is dimeric. The dimer is tightly coupled, with an intimate contact surface, implying that the dimer does not easily dissociate. The FlhD monomer is predominantly alpha -helical. The C-termini of both FlhD monomers (residues 83-116) are completely disrupted by crystal packing, implying that this region of FlhD is highly flexible. However, part of the C-terminus structure in chain A (residues 83-98) was modelled using a native FlhD crystal. What is seen in chain A suggests a classic DNA-binding, helix-turn-helix (HTH) motif. FlhD does not bind DNA by itself, so it may be that the DNA-binding HTH motif becomes rigidly defined only when FlhD forms a complex with some other protein, such as FlhC. If this were true, it might explain how FlhD exhibits plasticity in its DNA-binding specificity, as each partner protein with which it forms a complex could allosterically affect the binding specificity of its HTH motif. A disulphide bridge is seen between the unique cysteine residues (Cys-65) of FlhD native homodimers. Alanine substitution at Cys-65 does not affect FlhD transcription activator activity, suggesting that the disulphide bond is not necessary for either dimer stability or this function of FlhD. Electrostatic potential analysis indicates that dimeric FlhD has a negatively charged surface. C1 Univ Illinois, Coll Med, Dept Microbiol & Immunol, Chicago, IL 60612 USA. Argonne Natl Lab, Struct Biol Ctr, Argonne, IL 60439 USA. Mol Biol Consortium, Chicago, IL 60439 USA. RP Campos, A (reprint author), Univ Illinois, Coll Med, Dept Microbiol & Immunol, M-C 790,835 S Wolcott Ave,MSB E-603, Chicago, IL 60612 USA. FU NIGMS NIH HHS [GM59484] NR 50 TC 12 Z9 13 U1 1 U2 3 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0950-382X J9 MOL MICROBIOL JI Mol. Microbiol. PD FEB PY 2001 VL 39 IS 3 BP 567 EP 580 DI 10.1046/j.1365-2958.2001.02247.x PG 14 WC Biochemistry & Molecular Biology; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 403PR UT WOS:000167052100004 PM 11169099 ER PT J AU Predota, M Cummings, PT Chialvo, AA AF Predota, M Cummings, PT Chialvo, AA TI Pair approximation for polarization interaction: efficient method for Monte Carlo simulations of polarizable fluids SO MOLECULAR PHYSICS LA English DT Article ID PHASE COEXISTENCE PROPERTIES; WATER MODELS AB A new method is presented for the Monte Carlo simulations of polarizable models with induced dipole moments. This method updates induced dipole moments on all molecules when a single molecule is moved, without evaluating all pair interactions. Thus, depending on the number of molecules, it is 10-20 times faster than Monte Carlo simulations with full iteration. The efficiency makes it a powerful tool for the study of phase equilibria of polarizable models in grand canonical and Gibbs ensembles. C1 Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, High Temp Aqueous Chem Grp, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, High Temp Aqueous Chem Grp, Oak Ridge, TN 37831 USA. RP Predota, M (reprint author), Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. RI Predota, Milan/A-2256-2009; Cummings, Peter/B-8762-2013; OI Predota, Milan/0000-0003-3902-0992; Cummings, Peter/0000-0002-9766-2216; Chialvo, Ariel/0000-0002-6091-4563 NR 9 TC 20 Z9 20 U1 0 U2 6 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD FEB PY 2001 VL 99 IS 4 BP 349 EP 354 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 399MJ UT WOS:000166816700011 ER PT J AU Uhl, GR Volkow, N AF Uhl, GR Volkow, N TI Perspectives on reward circuitry, neurobiology, genetics and pathology: Dopamine and addiction SO MOLECULAR PSYCHIATRY LA English DT Editorial Material C1 NIDA, IRP, Baltimore, MD 21224 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Uhl, GR (reprint author), NIDA, IRP, POB 5180, Baltimore, MD 21224 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 1359-4184 J9 MOL PSYCHIATR JI Mol. Psychiatr. PD FEB PY 2001 VL 6 SU 1 BP S1 EP S1 PG 1 WC Biochemistry & Molecular Biology; Neurosciences; Psychiatry SC Biochemistry & Molecular Biology; Neurosciences & Neurology; Psychiatry GA 404JR UT WOS:000167094700002 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Thanos, P AF Volkow, ND Wang, GJ Fowler, JS Thanos, P TI Role of dopamine in drug abuse and addiction in human subjects: results from imaging studies SO MOLECULAR PSYCHIATRY LA English DT Meeting Abstract C1 SUNY Stony Brook, Brookhaven Natl Lab, New York, NY USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU NATURE PUBLISHING GROUP PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 1359-4184 J9 MOL PSYCHIATR JI Mol. Psychiatr. PD FEB PY 2001 VL 6 SU 1 BP S3 EP S4 PG 2 WC Biochemistry & Molecular Biology; Neurosciences; Psychiatry SC Biochemistry & Molecular Biology; Neurosciences & Neurology; Psychiatry GA 404JR UT WOS:000167094700008 ER PT J AU Zhang, MH Lin, JL Cederwall, RT Yio, JJ Xie, SC AF Zhang, MH Lin, JL Cederwall, RT Yio, JJ Xie, SC TI Objective analysis of ARM IOP data: Method and sensitivity SO MONTHLY WEATHER REVIEW LA English DT Article ID INTERTROPICAL CONVERGENCE ZONE; SYSTEM SIMULATION EXPERIMENTS; MIDLATITUDE SQUALL LINE; SCALE WAVE DISTURBANCES; SINGLE-COLUMN MODEL; PACIFIC WARM POOL; MOISTURE BUDGETS; TOGA COARE; TIBETAN PLATEAU; WESTERN PACIFIC AB Motivated by the need to obtain accurate objective analysis of field experimental data to force physical parameterizations in numerical models, this paper first reviews the existing objective analysis methods and interpolation schemes that are used to derive atmospheric wind divergence, vertical velocity, and advective tendencies, Advantages and disadvantages of different methods are discussed. It is shown that considerable uncertainties in the analyzed products can result from the use of different analysis. The paper then describes a hybrid approach to combine the strengths of the regular grid and the line-integral methods, together with a variational constraining procedure for the analysis of field experimental data. In addition to the use of upper air data, measurements at the surface and at the top of the atmosphere (TOA) are used to constrain the upper-air analysis to conserve column-integrated mass, water, energy, and momentum. Analyses are shown for measurements taken in the Atmospheric Radiation Measurement Program July 1995 intensive observational period. Sensitivity experiments are carried our to test the robustness of the analyzed data and to reveal uncertainties in the analysis. These include sensitivities to the interpolation schemes, to the types of input data sources, and to the variational constraining procedures. It is shown that the constraining process of using additional surface and TOA data significantly reduces the sensitivity of the final data products. C1 SUNY Stony Brook, Inst Terr & Planetary Atmospheres, Stony Brook, NY 11794 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Zhang, MH (reprint author), SUNY Stony Brook, Inst Terr & Planetary Atmospheres, Stony Brook, NY 11794 USA. RI Xie, Shaocheng/D-2207-2013 OI Xie, Shaocheng/0000-0001-8931-5145 NR 61 TC 127 Z9 130 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD FEB PY 2001 VL 129 IS 2 BP 295 EP 311 DI 10.1175/1520-0493(2001)129<0295:OAOAID>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 403RV UT WOS:000167057000007 ER PT J AU Dresselhaus, MS AF Dresselhaus, MS TI Support for physical sciences and engineering SO MRS BULLETIN LA English DT Editorial Material C1 US DOE, US Dept Energy, Off Sci, Washington, DC 20585 USA. RP Dresselhaus, MS (reprint author), US DOE, US Dept Energy, Off Sci, Washington, DC 20585 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD FEB PY 2001 VL 26 IS 2 BP 91 EP 92 DI 10.1557/mrs2001.293 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 405DU UT WOS:000167143300013 ER PT J AU Rumbles, G AF Rumbles, G TI Solid-state optics - A laser that turns down the heat SO NATURE LA English DT Editorial Material C1 Univ London Imperial Coll Sci Technol & Med, Dept Chem, Ctr Elect Mat & Devices, London SW7 2AY, England. Natl Renewable Energy Lab, Ctr Basic Sci, Golden, CO 80401 USA. RP Rumbles, G (reprint author), Univ London Imperial Coll Sci Technol & Med, Dept Chem, Ctr Elect Mat & Devices, London SW7 2AY, England. OI Rumbles, Garry/0000-0003-0776-1462 NR 6 TC 50 Z9 51 U1 0 U2 9 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD FEB 1 PY 2001 VL 409 IS 6820 BP 572 EP 573 DI 10.1038/35054649 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 397JJ UT WOS:000166692300027 PM 11214303 ER PT J AU Romanov, SR Kozakiewicz, BK Holst, CR Stampfer, MR Haupt, LM Tlsty, TD AF Romanov, SR Kozakiewicz, BK Holst, CR Stampfer, MR Haupt, LM Tlsty, TD TI Normal human mammary epithelial cells spontaneously escape senescence and acquire genomic changes SO NATURE LA English DT Article ID BREAST-CANCER; EXPRESSION; IMMORTALIZATION; INACTIVATION; METHYLATION; TELOMERES; PASSAGE; GROWTH; TRF2; P16 AB Senescence and genomic integrity are thought to be important barriers in the development of malignant lesions(1). Human fibroblasts undergo a limited number of cell divisions before entering an irreversible arrest, called senescence(2). Here we show that human mammary epithelial cells (HMECs) do not conform to this paradigm of senescence. In contrast to fibroblasts, HMECs exhibit an initial growth phase that is followed by a transient growth plateau (termed selection or M0; refs 3-5), from which proliferative cells emerge to undergo further population doublings (similar to 20-70), before entering a second growth plateau (previously termed senescence or M1; refs 4-6). We rnd that the first growth plateau exhibits characteristics of senescence but is not an insurmountable barrier to further growth. HMECs emerge from senescence, exhibit eroding telomeric sequences and ultimately enter telomere-based crisis to generate the types of chromosomal abnormalities seen in the earliest lesions of breast cancer. Growth past senescent barriers may be a pivotal event in the earliest steps of carcinogenesis, providing many genetic changes that predicate oncogenic evolution. The differences between epithelial cells and fibroblasts provide new insights into the mechanistic basis of neoplastic transformation. C1 Univ Calif San Francisco, Dept Pathol, San Francisco, CA 94143 USA. Univ Calif San Francisco, UCSF Comprehens Canc Ctr, San Francisco, CA 94143 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Tlsty, TD (reprint author), Univ Calif San Francisco, Dept Pathol, San Francisco, CA 94143 USA. RI Haupt, Larisa/C-6066-2017 NR 28 TC 329 Z9 339 U1 0 U2 17 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD FEB 1 PY 2001 VL 409 IS 6820 BP 633 EP 637 DI 10.1038/35054579 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 397JJ UT WOS:000166692300048 PM 11214324 ER PT J AU Pennacchio, LA Rubin, EM AF Pennacchio, LA Rubin, EM TI Genomic strategies to identify mammalian regulatory sequences SO NATURE REVIEWS GENETICS LA English DT Review ID LOCUS-CONTROL REGIONS; GENE-EXPRESSION; CPG ISLANDS; TRANSCRIPTIONAL REGULATION; MOUSE; DNA; IDENTIFICATION; ELEMENTS; YEAST; ALIGNMENT AB With the continuing accomplishments of the human genome project, high-throughput / strategies to identify DNA sequences that are important in mammalian gene regulation are becoming increasingly feasible. In contrast to the historic, labour-intensive, wet-laboratory methods for identifying regulatory sequences, many modern approaches are heavily focused. on the computational analysis of large genomic data sets. Data from inter-species genomic sequence comparisons and genome-wide expression profiling, integrated with various computational tools, are poised to contribute to the decoding of genomic sequence and to the identification of those sequences that orchestrate gene regulation. in this review, we highlight several genomic approaches that are being used to identify regulatory sequences in mammalian genomes. C1 Lawrence Berkeley Lab, Genome Sci Dept, Berkeley, CA 94720 USA. RP Rubin, EM (reprint author), Lawrence Berkeley Lab, Genome Sci Dept, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 80 TC 278 Z9 289 U1 0 U2 8 PU NATURE PUBLISHING GROUP PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 1471-0056 J9 NAT REV GENET JI Nat. Rev. Genet. PD FEB PY 2001 VL 2 IS 2 BP 100 EP 109 DI 10.1038/35052548 PG 10 WC Genetics & Heredity SC Genetics & Heredity GA 396ZD UT WOS:000166667500011 PM 11253049 ER PT J AU Balkey, JJ Wieneke, RE AF Balkey, JJ Wieneke, RE TI Transuranic waste management at Los Alamos National Laboratory SO NUCLEAR ENERGY-JOURNAL OF THE BRITISH NUCLEAR ENERGY SOCIETY LA English DT Article DE transuramic; plutonium; minimisation; computerised AB Los Alamos National Laboratory (LANL) was, the first to ship transuranic waste for deep geologic disposal in the waste isolation pilot plant (WIPP) in Carlsbad, New Mexico. This was the culmination of a tremendous effort on the part of personnel at the Plutonium Facility (TA-55) where the waste was generated and of LANL waste management personnel. The Plutonium Facility provides a wide variety of actinide research and development capabilities in support of national defence needs. Many of these operations produce a wide variety of waste forms, including transuranic waste from activities in the glove-box lines throughout the facility. Critical to the success of this shipment was the integrity of the waste management programme at TA-55. A group of dedicated waste management professionals worked intimately with actinide processing operations personnel to assure that all waste packages met the WIPP waste acceptance criteria and were documented and packaged in accordance with all applicable regulations. Records are largely computerised, eliminating paper forms and improving the integrity of data packages and expediting the review and approval process. Research into waste minimisation has succeeded in identifying processes to reduce the volumes of transuranic waste produced and has resulted in the implementation of decontamination and waste avoidance techniques in the facility. This paper provides a broad overview of current waste management activivities in the TA-55 Plutonium Facility. C1 Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Balkey, JJ (reprint author), Los Alamos Natl Lab, Div Nucl Mat Technol, POB 1663, Los Alamos, NM 87545 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU BRITISH NUCLEAR ENERGY SOC PI WESTMINSTER, LONDON PA 1-7 GREAT GEORGE ST, WESTMINSTER, LONDON SW1P 3AA, ENGLAND SN 0140-4067 J9 NUCL ENERG-J BR NUCL JI Nucl. Energy-J. Br. Nucl. Energy Soc. PD FEB PY 2001 VL 40 IS 1 BP 53 EP 58 DI 10.1680/nuen.40.1.53.39958 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 521FC UT WOS:000173827700012 ER PT J AU He, XY Li, N AF He, XY Li, N TI Exploring a potential high energy solution to the problem of long-lived waste SO NUCLEAR ENGINEERING INTERNATIONAL LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP He, XY (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU REED BUSINESS INFORMATION LTD PI SUTTON PA QUADRANT HOUSE THE QUADRANT, SUTTON SM2 5AS, SURREY, ENGLAND SN 0029-5507 J9 NUCL ENG INT JI Nucl. Eng. Int. PD FEB PY 2001 VL 46 IS 559 BP 16 EP 17 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 406ZC UT WOS:000167246000002 ER PT J AU Ichiguchi, K Wakatani, M Unemura, T Tatsuno, T Carreras, BA AF Ichiguchi, K Wakatani, M Unemura, T Tatsuno, T Carreras, BA TI Improved stability due to local pressure flattening in stellarators SO NUCLEAR FUSION LA English DT Article ID LARGE HELICAL DEVICE; HELIOTRON-E; IDEAL; INSTABILITIES; TRANSPORT; PHYSICS AB It is demonstrated that the stability of low n pressure gradient driven modes in stellarators is improved by local flattening of the pressure at low order rational surfaces. Here n is the toroidal mode number. Results are presented for the Large Helical Device with an inward magnetic axis shift of 25 cm. C1 Natl Inst Fus Sci, Oroshi, Toki, Japan. Kyoto Univ, Grad Sch Energy Sci, Uji, Kyoto, Japan. Univ Tokyo, Grad Sch Frontier Sci, Tokyo, Japan. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Ichiguchi, K (reprint author), Natl Inst Fus Sci, Oroshi, Toki, Japan. EM wakatani@energy.kyoto-u.ac.jp RI Tatsuno, Tomo/A-3467-2011 NR 18 TC 14 Z9 14 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0029-5515 EI 1741-4326 J9 NUCL FUSION JI Nucl. Fusion PD FEB PY 2001 VL 41 IS 2 BP 181 EP 187 DI 10.1088/0029-5515/41/2/304 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 449JX UT WOS:000169682400005 ER PT J AU Mazzucato, E AF Mazzucato, E TI Microwave imaging reflectometry for the visualization of turbulence in tokamaks SO NUCLEAR FUSION LA English DT Article ID FLUCTUATIONS; PLASMAS; SYSTEM AB Understanding the mechanism of anomalous transport in magnetically confined plasmas requires the use of sophisticated diagnostic tools for the measurement of turbulent fluctuations. The article describes the results of an extensive numerical study of microwave reflectometry in tokamaks showing that the two dimensional structure of plasma fluctuations near the cut-off can be obtained from the phase of reflected waves. This requires the latter to be collected by an optical system making an image of the reflecting layer onto an array of microwave receivers, and the amplitude of fluctuations to be below a threshold that is set by the spectrum of poloidal wavenumbers. The conceptual design of an experimental scheme for the global visualization of turbulent fluctuations in tokamaks is described. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Mazzucato, E (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 12 TC 46 Z9 47 U1 0 U2 1 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD FEB PY 2001 VL 41 IS 2 BP 203 EP 213 DI 10.1088/0029-5515/41/2/307 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 449JX UT WOS:000169682400008 ER PT J AU Kubo, H Sakurai, S Asakura, N Konoshima, S Tamai, H Higashijima, S Sakasai, A Takenaga, H Itami, E Shimizu, E Fujita, T Kamada, Y Koide, Y Shirai, H Sugie, T Nakano, T Oyama, N Urano, H Ishijima, T Hill, KW Ernst, DR Leonard, AW AF Kubo, H Sakurai, S Asakura, N Konoshima, S Tamai, H Higashijima, S Sakasai, A Takenaga, H Itami, E Shimizu, E Fujita, T Kamada, Y Koide, Y Shirai, H Sugie, T Nakano, T Oyama, N Urano, H Ishijima, T Hill, KW Ernst, DR Leonard, AW CA JT-60 TEAM TI High radiation and high density experiments in JT-60U SO NUCLEAR FUSION LA English DT Article ID ASDEX UPGRADE; MODE PLASMAS; DIII-D; CONFINEMENT; TRANSPORT; DIVERTOR; DEGRADATION; DISCHARGES; TURBULENCE; TEXTOR-94 AB In order to obtain improved confinement plasmas with high radiation at high density, Ar gas was injected into ELMy H mode plasmas in JT-60U. A confinement improvement of HH98(y,2) approximate to 1 was obtained with a high radiation loss power fraction (similar to 80%) at an electron density of similar to0.65n(GW). The HH factor was about 50% higher than that in plasmas without Ar injection. C1 Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 31101, Japan. Hokkaido Univ, Grad Sch Engn, Sapporo, Hokkaido, Japan. Nagoya Univ, Grad Sch Engn, Nagoya, Aichi, Japan. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Gen Atom Co, San Diego, CA USA. RP Kubo, H (reprint author), Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 31101, Japan. EM kubo@naka.jaeri.go.jp RI Ernst, Darin/A-1487-2010; Ishijima, Tatsuo/C-3337-2015; Kikuchi, Mitsuru/O-1036-2015; OI Ernst, Darin/0000-0002-9577-2809; Kikuchi, Mitsuru/0000-0002-5485-8737; Ishijima, Tatsuo/0000-0002-5237-3699 NR 24 TC 43 Z9 43 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0029-5515 EI 1741-4326 J9 NUCL FUSION JI Nucl. Fusion PD FEB PY 2001 VL 41 IS 2 BP 227 EP 233 DI 10.1088/0029-5515/41/2/310 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 449JX UT WOS:000169682400011 ER PT J AU James, RB Siffert, P AF James, RB Siffert, P TI Proceedings of the 11th International Workshop on Room Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics - International Atomic Energy Agency - Vienna, Austria, October 11-15, 1999 - Preface SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Editorial Material C1 Sandia Natl Labs, Livermore, CA 94550 USA. EMRS, Strasbourg, France. RP James, RB (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP VII EP VII DI 10.1016/S0168-9002(00)00844-5 PG 1 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400001 ER PT J AU Brunett, BA Van Scyoc, JM Schlesinger, TE James, RB AF Brunett, BA Van Scyoc, JM Schlesinger, TE James, RB TI The spatial response of CdZnTe gamma-ray detectors as measured by gamma-ray mapping SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE cadmium zinc telluride; mapping; gamma-ray detectors; spectrometer; unipolar ID OPTIMIZATION AB yWe have developed a system to measure the spatial response of cadmium zinc telluride (CZT) radiation detectors. Using this system we have measured the response of several novel detector designs including several variations of the unipolar design. We have observed a wide range of energy resolution and efficiency among the different device designs. Each design has unique strengths and weaknesses which affect the device performance. In addition to design effects on performance, several instances of poor material uniformity degrading the device performance have been observed. In this paper we will discuss the spatial detector response focusing on the effects of the detector design. Where appropriate, we will also discuss the observed effects of material uniformity on device performance. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RP Brunett, BA (reprint author), Sandia Natl Labs, MS 9671,POB 969, Livermore, CA 94551 USA. NR 12 TC 12 Z9 13 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 76 EP 84 DI 10.1016/S0168-9002(00)00854-8 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400012 ER PT J AU Greaves, CM Brunett, BA Van Scyoc, JM Schlesinger, TE James, RB AF Greaves, CM Brunett, BA Van Scyoc, JM Schlesinger, TE James, RB TI Material uniformity of CdZnTe grown by low-pressure Bridgman SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE cadmium zinc telluride; nuclear detector; uniformity; Bridgman technique; photoluminescence; mapping AB We have employed Low-Temperature Photoluminescence (LTPL) and Room-Temperature Photoluminescence Mapping (RTPLM) to explore the crystalline quality and material uniformity of Cadmium Zinc Telluride (CZT) radiation detector material grown by the Low-Pressure Bridgman (LPB) technique. We report on the differences in crystalline quality and uniformity of material supplied by eV Products Inc. and IMARAD Imaging Systems Ltd. In addition, we have examined the general detector response of the material supplied by IMARAD. We report on the uniformity of the detector response and the temperature dependence of this response when used as a detector, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Greaves, CM (reprint author), Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. OI Greaves, Colin/0000-0002-9568-3697 NR 4 TC 21 Z9 22 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 FEB 1 PY 2001 VL 458 IS 1-2 BP 96 EP 103 DI 10.1016/S0168-9002(00)00855-X PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400015 ER PT J AU Rybka, AV Leonov, SA Prokhoretz, IM Abyzov, AS Davydov, LN Kutny, VE Rowland, MS Smith, CF AF Rybka, AV Leonov, SA Prokhoretz, IM Abyzov, AS Davydov, LN Kutny, VE Rowland, MS Smith, CF TI Influence of detector surface processing on detector performance SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE semiconductor detector; surface passivation; gamma-ray spectroscopy ID CADMIUM ZINC TELLURIDE; HG1-XCDXTE; OXYGEN AB Characteristics of gamma ray semiconductor detectors essentially depend on properties of crystal surface. The status of a lateral surface influences surface leakage current of the detector, and the status of a surface, on which the contacts are made, influences properties of contacts and, thus, a volume leakage current and the highest possible bias voltage. In this connection several ways of processing the lateral surface of CdZnTe and CdTe crystals grown by a high-pressure Bridgman method were investigated: chemical etching, ion cleaning, passivation. Influence of a preliminary processing of a crystal surface on the properties of ohmic contacts is investigated. An analysis of electrophysical properties of crystals subjected to surface processing is carried out. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Kharkov Phys & Technol Inst, NSC, UA-310108 Kharkov, Ukraine. LLNL, Livermore, CA USA. RP Rybka, AV (reprint author), Kharkov Phys & Technol Inst, NSC, UA-310108 Kharkov, Ukraine. NR 8 TC 20 Z9 22 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 248 EP 253 DI 10.1016/S0168-9002(00)00868-8 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400036 ER PT J AU Pastuovic, Z Jaksic, M James, RB Chattopadhyay, K Ma, X Burger, A AF Pastuovic, Z Jaksic, M James, RB Chattopadhyay, K Ma, X Burger, A TI Influence of electrical contacts on charge collection profiles in CdZnTe studied by IBIC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE charge collection; CZT detector; IBICC profiling ID CADMIUM ZINC TELLURIDE; DETECTORS; CDTE AB The lateral and frontal modes of the nuclear microprobe technique ion beam-induced charge collection (IBICC) were used for imaging the electronic properties of CdZnTe room-temperature detectors. The detectors with different contacts (In-In, In-Au, Au-Au) were bombarded with a scanned 4 MeV proton microbeam. By measuring the detector response at bias voltages of up to several hundred volts, charge collection profiles: along the thickness of a detector were calculated for different shaping times, Obvious differences between the various contacts were observed in lateral IBICC efficiency profiles that varied in shape, height and smoothness. No hole collection contribution was observed at apllied voltages for all three configurations of the CZT detector. Electron mobility-lifetime products were calculated from measured IBICC efficiency profiles. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Rudjer Boskovic Inst, Zagreb 10001, Croatia. Sandia Natl Labs, Livermore, CA USA. Fisk Univ, Nashville, TN USA. RP Pastuovic, Z (reprint author), Rudjer Boskovic Inst, POB 1016, Zagreb 10001, Croatia. NR 7 TC 4 Z9 6 U1 1 U2 6 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 FEB 1 PY 2001 VL 458 IS 1-2 BP 254 EP 261 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400037 ER PT J AU Van Scyoc, JM Brunett, BA Schlesinger, TE James, RB AF Van Scyoc, JM Brunett, BA Schlesinger, TE James, RB TI Further investigation of the operation of Cd1-xZnxTe pixel array detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE cadmium zinc telluride; pixel array detectors; gamma-ray spectrometers; contacts ID GAMMA-RAY SPECTROMETERS; SPECTROSCOPY AB In this work we study the spectral performance of Cd1-xZnxTe pixel array detectors. The specific effects and relative importance of various detector parameters on spectral response are determined. While bulk material uniformity is still the factor most impacting detector performance, pixel size relative to detector thickness is found to also have a large impact. The localization of the charge induction profile, or weighting potential, leads to a reduction in the importance of hole transport. Thus, pixel geometry is a key design parameter setting spectroscopic performance. Finally, the contact material choice has some effect on performance, in that reductions in leakage current obtained with blocking gold contacts can improve the energy resolution for low photon energies, although the effect is small for small-area pixels. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RP Van Scyoc, JM (reprint author), Sandia Natl Labs, POB 969,MS 9671, Livermore, CA 94550 USA. NR 6 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 310 EP 318 DI 10.1016/S0168-9002(00)00875-5 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400044 ER PT J AU Luke, PN Amman, M Lee, JS Ludewigt, BA Yaver, H AF Luke, PN Amman, M Lee, JS Ludewigt, BA Yaver, H TI A CdZnTe coplanar-grid detector array for environmental remediation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE CdZnTe; semiconductor detector; gamma-ray; detector array AB A portable, room-temperature gamma-ray spectrometer is being developed for use in environmental remediation activities. Good energy resolution and high-detection efficiency are achieved using an array of CdZnTe coplanar-grid detectors. The array is of modular design, which allows for the stacking of an arbitrary number of detectors, as well as for the easy exchange of detectors for repairs if needed. Each element of the array consists of a 1 cm(3) detector and low-power readout electronics. Each detector module including the electronics fits within a small footprint of 1.4 cm x 1.4 cm, thus allowing the detectors to be closely packed. A compliant detector-mounting scheme has been developed to protect the detectors from mechanical shock and vibration expected in field use. A prototype ? x ? array has been constructed and evaluated. The design of the detector, detector module and test results from the array are presented. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Luke, PN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 6 TC 34 Z9 34 U1 0 U2 7 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 FEB 1 PY 2001 VL 458 IS 1-2 BP 319 EP 324 DI 10.1016/S0168-9002(00)00876-7 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400045 ER PT J AU Parnham, K Szeles, C Prettyman, TH Smith, M Stahle, C Parker, BH Wang, WL AF Parnham, K Szeles, C Prettyman, TH Smith, M Stahle, C Parker, BH Wang, WL TI Further studies on the modified two-terminal geometry for CdZnTe detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE CdZnTe; gamma ray detector; CAPture (TM) technology; charge transport; modified electric field ID SEMICONDUCTOR RADIATION DETECTORS; CD0.8ZN0.2TE AB This paper will report on additional studies undertaken on a novel electrode geometry, referred to as CAPture(TM) technology, wherein the cathode is extended up the sides of a planar CdZnTe detector. The initial presentation of this development focused on a single geometry, and a simple mechanism was proposed to explain the improved performance. In this presentation, we will describe the results of further electric field and charge transport modeling as applied to this detector configuration, and also compare the calculated performance with experimental results. (C) 2001 Elsevier Science B.V. All rights reserved. C1 eV PROD, Saxonburg, PA 16056 USA. Univ Calif Los Alamos Natl Lab, Safeguards Sci & Technol Grp, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Unisys Corp, Blue Bell, PA 19424 USA. RP Parnham, K (reprint author), eV PROD, 373 Saxonburg Blvd, Saxonburg, PA 16056 USA. OI Prettyman, Thomas/0000-0003-0072-2831 NR 7 TC 4 Z9 5 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 334 EP 338 DI 10.1016/S0168-9002(00)00878-0 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400047 ER PT J AU Manfredi, PF Ratti, L Re, V Roe, NA Speziali, V AF Manfredi, PF Ratti, L Re, V Roe, NA Speziali, V TI Noise limits of AToM, a128 channel CMOS readout chip in applications with room temperature high granularity detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE strip detection; X-ray imaging; gamma-ray imaging; ASIC; noise analysis ID SILICON VERTEX TRACKER AB AToM, a CMOS 128 channel signal processing chip, was originally designed for the readout of the microstrip Silicon Vertex Tracker in the BaBar experiment at SLAG. Each channel in the chip includes an analog section, with low-noise preamplification, shaping, and A/D conversion. A digital section provides data buffering and formatting, and serial sparsified readout. The chip is able to process signals from both electron and hole collecting electrodes on a wide dynamic range. AToM is presently available in both rad-soft and rad-hard implementations. This paper aims at showing that AToM has a much broader application perspective in association with room-temperature high-granularity detectors, for instance in X- and gamma-ray imaging and signal processing for focal plane detectors. The first step toward this extension is the analysis of the intrinsic noise and accuracy limitations in radiation energy measurements. For this purpose the analysis is focused on the noise performances of the analog section, as a function of the detector capacitance, and of the signal peaking time. The effect of series white and 1/f noise and of parallel noise is studied to define the best operating conditions with different detector types. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Bergamo, Dipartimento Ingn, I-24044 Dalmine, BG, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Ist Nazl Fis Nucl, Sez Pavia, I-27100 Pavia, Italy. Univ Pavia, Dipartimento Elettron, I-27100 Pavia, Italy. RP Re, V (reprint author), Univ Bergamo, Dipartimento Ingn, Viale Marconi 5, I-24044 Dalmine, BG, Italy. RI Roe, Natalie/A-8798-2012; Ratti, Lodovico/I-8836-2012; OI RATTI, LODOVICO/0000-0003-1906-1076; Re, Valerio/0000-0003-0697-3420 NR 12 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 382 EP 391 DI 10.1016/S0168-9002(00)00885-8 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400056 ER PT J AU Kutny, VE Rybka, AV Abyzov, AS Davydov, LN Komar, VK Rowland, MS Smith, CF AF Kutny, VE Rybka, AV Abyzov, AS Davydov, LN Komar, VK Rowland, MS Smith, CF TI AlSb single-crystal grown by HPBM SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE AlSb; single-crystal growth; semiconductors; high-pressure Bridgman; crucible material AB Theoretical prognosis for AlSb places this widegap compound among the best materials for room temperature detectors and spectrometers. However, results experimentally obtained with AlSb are somewhat discouraging showing the necessity for improving the compound quality. The main difficulties connected with single-crystal growth are high reactivity of the melt with crucible material and a high volatility of Sb. in order to counteract the latter obstacle, an attempt was undertaken to synthesize and grow AlSb crystals by HPBM under the inert gas pressure of 40 atm. Different crucible materials: aluminum oxide, vitreous carbon, quartz, graphite. beryllium oxide, and zirconium oxide were tested and their comparative analysis was made. The obtained crystals were investigated and some electrophysical properties measured. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. STC ISC, Kharkov, Ukraine. LLNL, Livermore, CA USA. RP Rybka, AV (reprint author), Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. NR 17 TC 17 Z9 21 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 448 EP 454 DI 10.1016/S0168-9002(00)01039-1 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400067 ER PT J AU Moss, CE Ianakiev, KD Prettyman, TH Smith, MK Sweet, MR AF Moss, CE Ianakiev, KD Prettyman, TH Smith, MK Sweet, MR TI Multi-element, large-volume CdZnTe detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE semiconductor; CdZnTe; detector; array ID SEMICONDUCTOR AB Many applications using gamma rays, such as the determination of the elemental composition of planetary bodies, require the detection of gamma rays in the energy range 100 keV-10 MeV in a light, compact, room-temperature system. The photopeak efficiency of a single CdZnTe detector is limited because the volume currently available is limited to about 3.4 cm(3). To achieve adequate efficiency, we have combined the signals from several large-volume, coplanar-grid CdZnTe detectors. At low energy, the signals are summed without requiring coincidence; at high energy, multi-fold coincidence is required to suppress the Compton continuum. To minimize noise, a signal from a single detector is only included in the sum if it exceeds a threshold set just above the noise. We describe the electronics, the single detectors, their packaging in thin-walled boxes, and the resulting spectra. The energy resolution for the combined spectrum is only slightly worse than the resolution of the single detectors. The effectiveness of the Compton suppression depends on the spectrum. The photopeak efficiency of the multi-element detector when the signals are summed without requiring coincidence is approximately the sum of the photopeak efficiencies of the single detectors, whereas the photopeak efficiency with Compton suppression is a more complicated function of the incident gamma-ray energy. These results indicate that a 27-element (3 x 3 x 3) array of 15 mm x 15 mm x 15 mm single detector elements can provide good gamma-ray data for planetary bodies and terrestrial applications requiring high-efficiency, good-resolution portable instruments. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Moss, CE (reprint author), Univ Calif Los Alamos Natl Lab, NIS-6,MS J562, Los Alamos, NM 87545 USA. OI Prettyman, Thomas/0000-0003-0072-2831 NR 11 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 455 EP 460 DI 10.1016/S0168-9002(00)00904-9 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400068 ER PT J AU Hermon, H Schieber, M Lee, EY McChesney, JL Goorsky, M Lam, T Meerson, E Yao, H Erickson, J James, RB AF Hermon, H Schieber, M Lee, EY McChesney, JL Goorsky, M Lam, T Meerson, E Yao, H Erickson, J James, RB TI CZT detectors fabricated from horizontal and vertical Bridgman-grown crystals SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE Cadmium Zinc Telluride (CZT); X-ray diffraction (XRD); horizontal Bridgman (HB); vertical high-pressure Bridgman (VHPB); IR transmission; transient charge technique (TCT); nuclear radiation detectors ID THERMOELECTRIC EMISSION-SPECTROSCOPY; THERMALLY STIMULATED CONDUCTIVITY; CDZNTE RADIATION DETECTORS; MERCURIC IODIDE DETECTORS; RAY AB Characterizations of Cd1-xZnxTe (0.04 < x < 0.24) detector crystals grown by vertical high-pressure Bridgman (VHPB), vertical ambient pressure Bridgman (VB), horizontal ambient pressure Bridgman (HB) and vapor-grown crystals obtained from various sources were compared. The following methods were applied: (1)Triaxial double crystal X-ray diffraction (TADXRD) to determine the crystal homogeneity and Zn content. (2) Sensitivity to radiation from high-flux X-rays to investigate detector efficiency and contacts. (3) Laser-induced transient charge technique (TCT) for measuring the carrier lifetimes. (4) Thermoelectric voltage spectroscopy (TEVS) and thermal-stimulated current spectroscopy, (TSC) to study the carrier traps. (5) IR imaging to characterize macroscopic crystalline defects. We compared cadmium zinc telluride crystals grown by different methods in order to understand better the nature of defects, which influence their nuclear spectroscopic response, and how the defects are affected by the growth technique. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Hebrew Univ Jerusalem, Grad Sch Appl Sci, IL-91904 Jerusalem, Israel. Sandia Natl Labs, Livermore, CA 94550 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Real Time Radiog Readout, IL-91487 Jerusalem, Israel. Univ Nebraska, Lincoln, NE USA. RP Schieber, M (reprint author), Hebrew Univ Jerusalem, Grad Sch Appl Sci, IL-91904 Jerusalem, Israel. RI McChesney, Jessica/K-8911-2013 OI McChesney, Jessica/0000-0003-0470-2088 NR 19 TC 3 Z9 5 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 503 EP 510 DI 10.1016/S0168-9002(00)00911-6 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400076 ER PT J AU Vizkelethy, G Brunett, BA Walsh, DS James, RB Doyle, BL AF Vizkelethy, G Brunett, BA Walsh, DS James, RB Doyle, BL TI Investigation of the electronic properties of cadmium zinc telluride (CZT) detectors using a nuclear microprobe SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 11th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors and Associated Electronics CY OCT 11-15, 1999 CL INT ATOM ENERGY AGCY HEADQUARTERS, VIENNA, AUSTRIA HO INT ATOM ENERGY AGCY HEADQUARTERS DE CZT detectors; transport properties; effects of defects; charge collection efficiency by ion beam ID CDTE AB The electronic transport properties of Cadmium Zinc Telluride (CZT) determine the charge collection efficiency (i.e. the signal quality) of CZT detectors. These properties vary on both macroscopic and microscopic scales and depend on the presence of impurities and defects introduced during the crystal growth. Ion Beam Induced Charge Collection (IBICC) is a proven albeit relatively new method to measure the charge collection efficiency. Using an ion microbeam, the charge collection efficiency can be mapped with submicron resolution, and the map of electronic properties (such as drift length) can be calculated from the measurement. A more sophisticated version of IBICC, the Time Resolved IBICC (TRIBICC) allows us to determine the mobility and the lifetime of the charge carriers by recording and analyzing the transient waveform of the detector signal. Furthermore, lateral IBICC and TRIBICC can provide information about how the charge collection efficiency depends on the depth where the charge carriers are generated. This allows one to deduce information on the distribution of the electric field and transport properties of the charge carriers along the detector axis. IBICC and TRIBICC were used at the Sandia microbeam facility to image electronic properties of several CZT detectors. From the lateral TRIBICC measurement the electron and hole drift length profiles were calculated. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Sandia Natl Labs, Livermore, CA USA. Idaho State Univ, Pocatello, ID 83209 USA. RP Vizkelethy, G (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 1 PY 2001 VL 458 IS 1-2 BP 563 EP 567 DI 10.1016/S0168-9002(00)00917-7 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 401UJ UT WOS:000166946400084 ER PT J AU Seyboth, P Bachler, J Barna, D Barnby, LS Bartke, J Barton, RA Betev, L Bialkowska, H Billmeier, A Blume, C Blyth, CO Boimska, B Bracinik, J Brady, FP Brun, R Buncic, P Carr, L Cebra, D Cooper, GE Cramer, JG Csato, P Eckardt, V Eckhardt, F Ferenc, D Fischer, HG Fodor, Z Foka, P Freund, P Friese, V Ftacnik, J Gal, J Ganz, R Gazdzicki, M Gladysz, E Grebieszkow, J Harris, JW Hegyi, S Hlinka, V Hohne, C Igo, G Ivanov, M Jacobs, P Janik, R Jones, PG Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B Lednicky, R Levai, P Malakhov, AI Margetis, S Markert, C Mayes, BW Melkumov, GL Molnar, J Nelson, JM Odyniec, G Oldenburg, MD Palla, G Panagiotou, AD Petridis, A Pikna, M Pinsky, I Poskanzer, AM Prindle, DJ Puhlhofer, F Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rybicki, A Sammer, T Sandovai, A Sann, H Semenov, AY Schafer, E Schmitz, N Seyboth, P Sikler, F Sitar, B Skrzypczak, E Snellings, R Squier, GTA Stock, R Strmen, P Strobele, H Susa, T Szarka, I Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Ullrich, T Varga, D Vassiliou, M Veres, GI Vesztergombi, G Voloshin, S Vranic, D Wang, F Weerasundara, DD Wenig, S Whitten, C Xu, N Yates, TA Yoo, IK Zimanyi, J AF Seyboth, P Bachler, J Barna, D Barnby, LS Bartke, J Barton, RA Betev, L Bialkowska, H Billmeier, A Blume, C Blyth, CO Boimska, B Bracinik, J Brady, FP Brun, R Buncic, P Carr, L Cebra, D Cooper, GE Cramer, JG Csato, P Eckardt, V Eckhardt, F Ferenc, D Fischer, HG Fodor, Z Foka, P Freund, P Friese, V Ftacnik, J Gal, J Ganz, R Gazdzicki, M Gladysz, E Grebieszkow, J Harris, JW Hegyi, S Hlinka, V Hohne, C Igo, G Ivanov, M Jacobs, P Janik, R Jones, PG Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B Lednicky, R Levai, P Malakhov, AI Margetis, S Markert, C Mayes, BW Melkumov, GL Molnar, J Nelson, JM Odyniec, G Oldenburg, MD Palla, G Panagiotou, AD Petridis, A Pikna, M Pinsky, I Poskanzer, AM Prindle, DJ Puhlhofer, F Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rybicki, A Sammer, T Sandovai, A Sann, H Semenov, AY Schafer, E Schmitz, N Seyboth, P Sikler, F Sitar, B Skrzypczak, E Snellings, R Squier, GTA Stock, R Strmen, P Strobele, H Susa, T Szarka, I Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Ullrich, T Varga, D Vassiliou, M Veres, GI Vesztergombi, G Voloshin, S Vranic, D Wang, F Weerasundara, DD Wenig, S Whitten, C Xu, N Yates, TA Yoo, IK Zimanyi, J CA NA49 Collaboration TI Correlations and fluctuations in Pb plus Pb collisons SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT IXth International Workshop on Multiparticle Production CY JUN 12-17, 2000 CL TURIN, ITALY SP Fdn CRT, Inst Nazl Fis Nucl, Torino Univ, Rector, Assessorato alla Cultura della Reg Piemonte, Univ Trieste, Bologna ID HEAVY-ION COLLISIONS; NUCLEAR COLLISIONS; FLOW; INTERFEROMETRY AB Results on two-particle correlations, deuteron production, event anisotropy and event.-by-event fluctuations of (pT) and K/pi were obtained by the NA49 experiment in Pb+Pb collisions at 158 A(.)GeV beam energy. The interpretation of the measurements is discussed in light of the search for deconfinement. C1 CERN, CH-1211 Geneva 23, Switzerland. Univ Athens, Dept Phys, Athens, Greece. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Slovak Acad Sci, Inst Phys, Bratislava, Slovakia. KRKI Res Inst Particle & Nucl Phys, Budapest, Hungary. Inst Nucl Phys, Krakow, Poland. Gesell Schwerionenforsch Inst Darmstadt, GSI, D-6100 Darmstadt, Germany. Univ Calif Davis, Davis, CA 95616 USA. Joint Inst Nucl Res, Dubna, Russia. Goethe Univ Frankfurt, Fachbereich Phys, D-6000 Frankfurt, Germany. Univ Houston, Houston, TX USA. Kent State Univ, Kent, OH 44242 USA. Univ Calif Los Angeles, Los Angeles, CA USA. Univ Marburg, Fachbereich Phys, D-3550 Marburg, Germany. Max Planck Inst Phys & Astrophys, D-80805 Munich, Germany. Inst Nucl Studies, PL-00681 Warsaw, Poland. Univ Warsaw, Inst Expt Phys, Warsaw, Poland. Univ Washington, Nucl Phys Lab, Seattle, WA 98195 USA. Yale Univ, New Haven, CT 06520 USA. Rudjer Boskovic Inst, Zagreb, Croatia. RP CERN, CH-1211 Geneva 23, Switzerland. EM pxs@mppmu.mpg.de RI Barnby, Lee/G-2135-2010; Voloshin, Sergei/I-4122-2013; Levai, Peter/A-1544-2014; Lednicky, Richard/K-4164-2013; Carr, Lincoln/E-3819-2016 OI Barnby, Lee/0000-0001-7357-9904; Carr, Lincoln/0000-0002-4848-7941 NR 27 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD FEB PY 2001 VL 92 BP 7 EP 15 DI 10.1016/S0920-5632(00)01014-8 PG 9 WC Physics, Particles & Fields SC Physics GA 409GQ UT WOS:000167376500003 ER PT J AU Davis, CB AF Davis, CB TI Assessment of the ATHENA code for calculating the void fraction of a lead-bismuth/steam mixture in vertical upflow SO NUCLEAR TECHNOLOGY LA English DT Article AB Lead-bismuth is currently being considered as a coolant for fast reactors designed to produce low-cost electricity as well as burn actinides. Lead-bismuth fluid properties have been added to the ATHENA code so that it can be used in the thermal-hydraulic analysis of lead-bismuth-cooled reactors. The capability of ATHENA to calculate the void fraction of a two-component, two-phase mixture of liquid lead-bismuth and steam in cocurrent upflow was assessed using the El-Boher and Lesin void correlation. The assessment showed that the drift flux correlations currently available in the code predicted trends that were in reasonable agreement with the El-Boher and Lesin void correlation, bur the predicted void fractions were significantly too high. For example, the Kataoka-Ishii correlation, which was the best of the available correlations, predicted void fractions that were up To 30% greater than the values from the El-Boher and Lesin correlation. Consequently the El-Boher and Lesin correlation was implemented in a modified version of ATHENA. The implementation was complicated by the fact that the El-Boher and Lesin correlation was an explicit correlation for void fraction rather than a drift flux correlation. An approach was developed so that the code's basic drift flux formulation could be used to easily implement an explicit void correlation. The predictions of the modified code were in excellent agreement with the El-Boher and Lesin void correlation. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Davis, CB (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD FEB PY 2001 VL 133 IS 2 BP 187 EP 193 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 394ND UT WOS:000166529400004 ER PT J AU Hagrman, DL Rempe, JL AF Hagrman, DL Rempe, JL TI Corium oxidation at temperatures above 2000 K SO NUCLEAR TECHNOLOGY LA English DT Article AB A mechanistic model, based on a quasi-equilibrium analysis of oxidation reactions, is proposed for predicting high-temperature cerium oxidation, The analysis suggests that oxide forming on the surface of corium containing uranium, zirconium, and iron is similar to the oxides formed on zirconium and uranium as long as there is a small percentage of unoxidized zirconium or uranium in the metallic phase. This is because of the higher affinity of zirconium and uranium for oxygen. Hence, oxidation rates and heat production rates are similar to (U,Zr) compounds until nearly all the uranium and zirconium in the cerium oxidizes. Oxidation rates after this point are predicted to be similar to those implied by the oxide thickness present when the forming oxide ceases To be protective, and heat generation rates should be similar to those implied by iron oxidation, i.e., similar to4% of the zirconium oxidation heating rate. The maximum atomic ratio of unoxidized iron to unoxidized liquid zirconium plus uranium for the formation of a solid protective oxide below 2800 K is estimated for a temperature, T(in Kelvin), as follows: unoxidized iron / unoxidized zirconium + uranium = 1/28 root 54.7/exp-(147 061 + 12.08T log(T) - 61.03T - 0.000555T(2) / 1.986T) As long as this limit is not exceeded, either zirconium or uranium metal oxidation rates and heating describe the cerium oxidation rate. If this limit is exceeded, diffusion of steam to the cerium surface will limit the oxidation rate, and linear time-dependent growth of a nonprotective, mostly FeO, layer will occur below the protective (Zr, U) O-2 scale, When this happens, the oxidation should be at the constant rate given by the thickness of the protective layer. Heat generation should be similar to that of iron oxidation. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Hagrman, DL (reprint author), 1895 Carmel Dr, Idaho Falls, ID 83402 USA. OI Rempe, Joy/0000-0001-5527-3549 NR 36 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD FEB PY 2001 VL 133 IS 2 BP 194 EP 212 PG 19 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 394ND UT WOS:000166529400005 ER PT J AU Tedder, DW Finney, BC AF Tedder, DW Finney, BC TI Concepts in waste management: Cerium-promoted dissolution of refractory actinide oxides SO NUCLEAR TECHNOLOGY LA English DT Article ID ELECTROCHEMICAL TREATMENT; HAZARDOUS WASTES; ETHYLENE-GLYCOL; OXIDATION AB The effective dissolution of refractory plutonium oxide (fired to T greater than or equal to 1000 degreesC) can be carried out by forming eerie nitrate in nitric acid. Preliminary engineering concepts are presented for dissolving such actinide species in the presence of contaminated high-efficiency particulate air (HEPA) filters and incinerator ashes to permit actinide recovery using conventional wet methods. An electrochemical oxidation tank is envisioned with electrodes mounted on the tank lid to facilitate remote operation and maintenance. Contaminated HEPA filters can be treated using an upflow reactor in which eerie nitrate is recirculated between an oxidation tank and a reactor. A membrane separating the electrodes is not required, but special materials of construction are required for all equipment in direct contact with eerie nitrate (e.g., titanium or glass-lined vessels). Since this oxidant is easily reduced to cerous nitrate using oxalic acid, subsequent actinide recovery can be curried out in conventional stainless steel equipment after reduction. The concepts described have been demonstrated on the bench scale. C1 Georgia Inst Technol, Sch Chem Engn, Atlanta, GA 30332 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tedder, DW (reprint author), Georgia Inst Technol, Sch Chem Engn, Atlanta, GA 30332 USA. NR 68 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD FEB PY 2001 VL 133 IS 2 BP 242 EP 252 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 394ND UT WOS:000166529400008 ER PT J AU Brodkin, CA Moon, JD Camp, J Echeverria, D Redlich, CA Willson, RA Checkoway, H AF Brodkin, CA Moon, JD Camp, J Echeverria, D Redlich, CA Willson, RA Checkoway, H TI Serum hepatic biochemical activity in two populations of workers exposed to styrene SO OCCUPATIONAL AND ENVIRONMENTAL MEDICINE LA English DT Article DE hepatotoxicity; styrene; surveillance; bilirubin; aminotransferases ID LIVER-DISEASE; BILIRUBIN; HEPATOTOXICITY; RATS; SOLVENTS AB Objective - To determine whether hepatic biochemical changes, as measured by routinely available tests indicative of hepatocellular necrosis, cholestasis, or altered hepatic clearance of bilirubin, occur in association with low to moderate exposure to styrene commonly experienced in industrial production. Methods - Two independent cross sectional studies were performed comparing serum hepatic transaminases (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)), cholestatic enzymes (alkaline phosphatase (AP) and gamma glutamyl transpeptidase (GGT)), and bilirubin in (a) 47 workers of fibreglass reinforced plastics who were exposed to styrene and (b) 21 boat and tank fabricators, with separate referent groups of unexposed workers. Exposure to styrene was assessed in air by dosimetry, and in venous blood by headspace analysis. Hepatic biochemical variables were assessed across strata of exposure to styrene defined as 25 ppm in air, or 0.275 mg/l in blood, adjusting for age, sex, body mass index, and ethanol consumption. Results - A consistent and significant linear trend for increasing direct bilirubin and direct/total bilirubin ratio was found in association with increasing exposure to styrene, by both air and blood monitoring, in both studies. Mean direct bilirubin concentrations increased from 0.05-0.08 mg% in referents to 0.12-0.19 in workers exposed above 25 ppm, with a significant exposure-response trend (p<0.005). Significantly increased direct/total bilirubin ratios, ranging from 0.22 to 0.35 were associated with exposure to styrene (p<0.001), indicating diminished hepatic clearance of conjugated bilirubin. Also, a significant linear association between the hepatic transaminases ALT and AST and exposure to styrene was found in pooled regression analyses, with an increase in AP of about 10 IU/ml in workers exposed above 25 ppm air or 0.275 mg/l blood styrene in pooled analyses from both studies. Conclusions - The consistent finding of increased direct bilirubin and AP concentrations in these two independent studies provides evidence for diminished hepatic clearance of conjugated bilirubin with associated cholestasis in workers exposed to styrene. The finding of a significant linear association between hepatic transaminase concentrations and exposure to styrene in pooled analyses is consistent with mild hepatic injury and associated metabolic dysfunction. C1 Univ Washington, Dept Med, Seattle, WA 98195 USA. Harborview Med Ctr, Dept Environm Hlth, Seattle, WA 98104 USA. Chonnam Natl Univ, Dept Prevent Med, Kwangju, South Korea. Battelle Seattle Res Ctr, Seattle, WA USA. Yale Univ, Dept Internal Med, New Haven, CT USA. RP Brodkin, CA (reprint author), Univ Washington, Dept Med, Seattle, WA 98195 USA. FU NIEHS NIH HHS [5-K07-ES00237-02, ES04696]; NIOSH CDC HHS [OH-02629] NR 41 TC 12 Z9 12 U1 0 U2 0 PU BRITISH MED JOURNAL PUBL GROUP PI LONDON PA BRITISH MED ASSOC HOUSE, TAVISTOCK SQUARE, LONDON WC1H 9JR, ENGLAND SN 1351-0711 J9 OCCUP ENVIRON MED JI Occup. Environ. Med. PD FEB PY 2001 VL 58 IS 2 BP 95 EP 102 DI 10.1136/oem.58.2.95 PG 8 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 397ZJ UT WOS:000166728800004 PM 11160987 ER PT J AU Naumburg, E Ellsworth, DS Katul, GG AF Naumburg, E Ellsworth, DS Katul, GG TI Modeling dynamic understory photosynthesis of contrasting species in ambient and elevated carbon dioxide SO OECOLOGIA LA English DT Article DE daily photosynthesis; sunflecks; shade tolerance; elevated carbon dioxide; photosynthetic enhancement ID SHADE-TOLERANCE; FOREST UNDERSTORY; LOW-LIGHT; ALOCASIA-MACRORRHIZA; SEEDLING RESPONSES; ATMOSPHERIC CO2; TREE SEEDLINGS; GROWTH-RATE; PLANTS; SUNFLECKS AB Dynamic responses of understory plants to sunflecks have been extensively studied, but how much differences in dynamic light responses affect daily photosynthesis (A(day)) is still the subject of active research. Recent models of dynamic photosynthesis have provided a quantitative tool that allows the critical assessment of the importance of these sunfleck responses on A(day). Here we used a dynamic photosynthesis model to assess differences in four species that were growing in ambient and elevated CO2. We hypothesized that Liriodendron tulipifera, a species with rapid photosynthetic induction gain and slow induction loss, would have the least limitations to sunfleck photosynthesis relative to the other three species (Acer rubrum, Cornus florida, Liquidambar styraciflua). As a consequence, L. tulipifera should have the highest A(day) in an understory environment, despite being the least shade tolerant of the species tested. We further hypothesized that daily photosynthetic enhancement by elevated CO2 would differ from enhancement levels observed during light-saturated, steady-state measurements. Both hypotheses were supported by the model results under conditions of low daily photosynthetic photon flux density (PFD: <3% of the above-canopy PFD). However, under moderate PFD (10-20% of the above-canopy PFD), differences in dynamic sunfleck responses had no direct impact on A(day) for any of the species, since stomatal and photosynthetic induction limitations to sunfleck photosynthesis were small. Thus, the relative species ranking in A(day) under moderate PFD closely matched their rankings in steady-state measurements of light-saturated photosynthesis. Similarly, under elevated CO2, enhancement of modeled A(day) over A(day) at ambient CO2 matched the enhancement measured under light saturation. Thus, the effects of species-specific differences in dynamic sunfleck responses, and differences in elevated CO2 responses of daily photosynthesis, are most important in marginal light environments. C1 Desert Res Inst, Las Vegas, NV 89119 USA. Duke Univ, Nicholas Sch Environm, Durham, NC 27708 USA. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. RP Desert Res Inst, 755 E Flamingo Rd, Las Vegas, NV 89119 USA. EM elke@dri.edu RI Katul, Gabriel/A-7210-2008; OI Katul, Gabriel/0000-0001-9768-3693; Ellsworth, David/0000-0002-9699-2272 NR 47 TC 29 Z9 29 U1 3 U2 19 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0029-8549 EI 1432-1939 J9 OECOLOGIA JI Oecologia PD FEB PY 2001 VL 126 IS 4 BP 487 EP 499 DI 10.1007/s004420000543 PG 13 WC Ecology SC Environmental Sciences & Ecology GA 408QL UT WOS:000167339100005 ER PT J AU Rustad, LE Campbell, JL Marion, GM Norby, RJ Mitchell, MJ Hartley, AE Cornelissen, JHC Gurevitch, J AF Rustad, LE Campbell, JL Marion, GM Norby, RJ Mitchell, MJ Hartley, AE Cornelissen, JHC Gurevitch, J CA GCTE-NEWS TI A meta-analysis of the response of soil respiration, net nitrogen mineralization, and aboveground plant growth to experimental ecosystem warming SO OECOLOGIA LA English DT Review DE global warming; meta-analysis; soil respiration; nitrogen mineralization; plant productivity ID SIMULATED ENVIRONMENTAL-CHANGE; DWARF SHRUB HEATH; TRACE GAS FLUXES; INTERNATIONAL TUNDRA EXPERIMENT; ARCTIC POLAR SEMIDESERT; SPRUCE-FIR FOREST; CLIMATE-CHANGE; LITTER DECOMPOSITION; TERRESTRIAL ECOSYSTEMS; REPRODUCTIVE DEVELOPMENT AB Climate change due to greenhouse gas emissions is predicted to raise the mean global temperature by 1.0-3.5 degreesC in the next 50-100 years. The direct and indirect effects of this potential increase in temperature on terrestrial ecosystems and ecosystem processes are likely to be complex and highly varied in time and space. The Global Change and Terrestrial Ecosystems core project of the International Geosphere-Biosphere Programme has recently launched a Network of Ecosystem Warming Studies, the goals of which are to integrate and foster research on ecosystem-level effects of rising temperature. In this paper, we use meta-analysis to synthesize data on the response of soil respiration, net N mineralization, and aboveground plant productivity to experimental ecosystem warming at 32 research sites representing four broadly defined biomes, including high (latitude or altitude) tundra, low tundra, grassland, and forest. Warming methods included electrical heat-resistance ground cables, greenhouses, vented and unvented field chambers, overhead infrared lamps, and passive nighttime warming. Although results from individual sites showed considerable variation in response to warming, results from the meta-analysis showed that, across all sites and years, 2-9 years of experimental warming in the range 0.3-6.0 degreesC significantly increased soil respiration rates by 20% (with a 95% confidence interval of 18-22%), net N mineralization rates by 46% (with a 95% confidence interval of 30-64%). and plant productivity by 19% (with a 95% confidence interval of 15-23%). The response of soil respiration to warming was generally larger in forested ecosystems compared to low tundra and grassland ecosystems, and the response of plant productivity was generally larger in low tundra ecosystems than in forest and grassland ecosystems. With the exception of aboveground plant productivity, which showed a greater positive response to warming in colder ecosystems, the magnitude of the response of these three processes to experimental warming was not generally significantly related to the geographic, climatic, or environmental variables evaluated in this analysis. This underscores the need to understand the relative importance of specific factors (such as temperature, moisture, site quality, vegetation type, successional status, land-use history, etc.) at different spatial and temporal scales, and suggests that we should be cautious in "scaling up" responses from the plot and site level to the landscape and biome level. Overall, ecosystem-warming experiments are shown to provide valuable insights on the response of terrestrial ecosystems to elevated temperature. C1 US Forest Serv, NE Res Stn, Durham, NH 03824 USA. Desert Res Inst, Reno, NV 89512 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. SUNY Coll Environm Sci & Forestry, Syracuse, NY 13210 USA. Marine Biol Lab, Ctr Ecosyst, Woods Hole, MA 02543 USA. Univ Sheffield, Dept Anim & Plant Sci, Sheffield Ctr Arctic Ecol, Sheffield S10 2TN, S Yorkshire, England. SUNY Stony Brook, Dept Ecol & Evolut, Stony Brook, NY 11794 USA. RP Rustad, LE (reprint author), US Forest Serv, NE Res Stn, Durham, NH 03824 USA. RI Norby, Richard/C-1773-2012; Welker, Jeffrey/C-9493-2013; Verburg, Paul/B-6351-2014; OI Norby, Richard/0000-0002-0238-9828; Campbell, John/0000-0003-4956-1696 NR 114 TC 1009 Z9 1133 U1 102 U2 809 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0029-8549 J9 OECOLOGIA JI Oecologia PD FEB PY 2001 VL 126 IS 4 BP 543 EP 562 PG 20 WC Ecology SC Environmental Sciences & Ecology GA 408QL UT WOS:000167339100012 ER PT J AU Hastwell, GT AF Hastwell, GT TI On disturbance and diversity: a reply to Mackey and Currie SO OIKOS LA English DT Article ID SUCCESSION; COMMUNITY; PATTERNS; DYNAMICS; HISTORY; PLANTS; MODELS C1 Univ Adelaide, Dept Environm Biol, Adelaide, SA 5005, Australia. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hastwell, GT (reprint author), Univ Adelaide, Dept Environm Biol, Adelaide, SA 5005, Australia. NR 26 TC 10 Z9 10 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0030-1299 J9 OIKOS JI Oikos PD FEB PY 2001 VL 92 IS 2 BP 367 EP 371 DI 10.1034/j.1600-0706.2001.920220.x PG 5 WC Ecology SC Environmental Sciences & Ecology GA 412NF UT WOS:000167560700020 ER PT J AU Montcalm, C Bajt, S Seely, JF AF Montcalm, C Bajt, S Seely, JF TI MoRu-Be multilayer-coated grating with 10.4% normal-incidence efficiency near the 11.4-nm wavelength SO OPTICS LETTERS LA English DT Article ID X-RAY; REGION AB A MoRu-Be multilayer coating was applied to a diffraction grating to enhance the grating's normal-incidence efficiency near 11.4 nm wavelength. The holographic grating substrate had a blazed groove profile with 2400 grooves/mm and a microroughness of 0.8 nm. The efficiency in the second diffraction order, measured with synchrotron radiation, was 10.4% at a wavelength of 11.37 nm. (C) 2001 Optical Society of America. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. USN, Div Space Sci, Res Lab, Washington, DC 20375 USA. RP Montcalm, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-395,POB 808, Livermore, CA 94551 USA. RI Bajt, Sasa/G-2228-2010 NR 9 TC 15 Z9 15 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD FEB 1 PY 2001 VL 26 IS 3 BP 125 EP 127 DI 10.1364/OL.26.000125 PG 3 WC Optics SC Optics GA 398KH UT WOS:000166755300003 PM 18033524 ER PT J AU Blank, JG Miller, GH Ahrens, MJ Winans, RE AF Blank, JG Miller, GH Ahrens, MJ Winans, RE TI Experimental shock chemistry of aqueous amino acid solutions and the cometary delivery of prebiotic compounds SO ORIGINS OF LIFE AND EVOLUTION OF BIOSPHERES LA English DT Article DE amino acids; comets; impact delivery; origin of life; shock recovery experiments ID MURCHISON METEORITE; ORGANIC-MOLECULES; PRIMITIVE EARTH; TUBE PYROLYSIS; HALLEY DUST; WAVES; DECOMPOSITION; METAMORPHISM; PRESSURE; KINETICS AB A series of shock experiments were conducted to assess the feasibility of the delivery of organic compounds to the Earth via cometary impacts. Aqueous solutions containing near-saturation levels of amino acids (lysine, norvaline, aminobutyric acid, proline, and phenylalanine) were sealed inside stainless steel capsules and shocked by ballistic impact with a steel projectile plate accelerated along a 12-m-long gun barrel to velocities of 0.5-1.9 km sec(-1). Pressure-temperature-time histories of the shocked fluids were calculated using 1D hydrodynamical simulations. Maximum conditions experienced by the solutions lasted 0.85-2.7 mus and ranged from 5.1-21 GPa and 412-870 K. Recovered sample capsules were milled open and liquid was extracted. Samples were analyzed using high performance liquid chromatography (HPLC) and mass spectrometry (MS). In all experiments, a large fraction of the amino acids survived. We observed differences in kinetic behavior and the degree of survivability among the amino acids. Aminobutyric acid appeared to be the least reactive, and phenylalanine appeared to be the most reactive of the amino acids. The impact process resulted in the formation of peptide bonds; new compounds included amino acid dimers and cyclic diketopiperazines. In our experiments, and in certain naturally occurring impacts, pressure has a greater influence than temperature in determining reaction pathways. Our results support the hypothesis that significant concentrations of organic material could survive a natural impact process. C1 Univ Calif Berkeley, Dept Earth & Planetary Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Appl Numer Algorithms Grp, Berkeley, CA 94720 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Blank, JG (reprint author), Univ Calif Berkeley, Dept Earth & Planetary Sci, 301 McCone Hall, Berkeley, CA 94720 USA. EM jenblank@seismo.berkeley.edu NR 68 TC 70 Z9 70 U1 23 U2 53 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0169-6149 J9 ORIGINS LIFE EVOL B JI Orig. Life Evol. Biosph. PD FEB-APR PY 2001 VL 31 IS 1-2 BP 15 EP 51 DI 10.1023/A:1006758803255 PG 37 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 415TC UT WOS:000167737900003 PM 11296518 ER PT J AU Indacochea, JE Smith, JL Litko, KR Karell, EJ Raraz, AG AF Indacochea, JE Smith, JL Litko, KR Karell, EJ Raraz, AG TI High-temperature oxidation and corrosion of structural materials in molten chlorides SO OXIDATION OF METALS LA English DT Article DE high temperature; oxidation; corrosion; molten chlorides ID OXIDE AB A molten salt-based process for treatment of spent oxide fuels is under development at the Argonne National Laboratory. A major part of the development effort involves identification of corrosion-resistant structural materials for the process vessels. Coupons of two stainless steels, tantalum, and two Inconel alloys were submitted to a corrosion test in an argon atmosphere with 10% oxygen. The coupons were partially immersed in molten lithium chloride salt containing small amounts of lithium metal, lithium oxide, and lithium nitride. Two sets of coupons were tested, the first at 750 degreesC for 30 days and the second at 650 degreesC for 6 days. Coupons of the first set corroded completely. In the second set of coupons, all corroded to some extend, but Inconel 600 showed the best performance overall. The salt-exposed region generally showed the greatest corrosion in the other coupons. One of the 316L SS coupons was welded and the weld area was severely attacked. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Indacochea, JE (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 21 TC 33 Z9 40 U1 0 U2 9 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0030-770X J9 OXID MET JI Oxid. Met. PD FEB PY 2001 VL 55 IS 1-2 BP 1 EP 16 DI 10.1023/A:1010333407304 PG 16 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 425HL UT WOS:000168285100001 ER PT J AU Walker, AB Tsouris, C DePaoli, DW Klasson, KT AF Walker, AB Tsouris, C DePaoli, DW Klasson, KT TI Ozonation of soluble organics in aqueous solutions using microbubbles SO OZONE-SCIENCE & ENGINEERING LA English DT Article DE ozone; ozonation; microbubble; bubble diffuser ozonation; electrostatic spraying ozonation; dissolved organics; benzene; toluene; ethylbenzene; xylene; BTEX; ionic strength ID OZONE DECOMPOSITION; PULSE-RADIOLYSIS; WATER; REACTORS; REMOVAL AB This work investigates ozonation of a mixture of benzene, toluene, ethylbenzene, and xylenes (BTEX) dissolved in aqueous solutions having salt concentrations ranging from 0 to 2 M. The effect of microbubbles on the ozonation rate is examined. Microbubbles are formed either by an electrostatic spraying method or by a small-pore bubble diffuser. Although electrostatic spraying is effective for BTEX removal in low-conductivity solutions, results indicate it is not suitable for microbubble formation in high-ionic-strength solutions due to high electric current. In contrast, the bubble-diffuser method proved to be very effective in producing small bubbles in high-ionic-strength solutions. The production of small bubbles makes it possible to mitigate the mass transfer limitation, which has been shown to be the primary restriction in ozonation systems. When a bubble diffuser is employed, the removal rate of BTEX from simulated seawater is approximately twice that obtained with a simple capillary tube. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tsouris, C (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Tsouris, Costas/C-2544-2016; OI Tsouris, Costas/0000-0002-0522-1027; Klasson, K. Thomas/0000-0003-3358-3081 NR 20 TC 15 Z9 15 U1 2 U2 11 PU LEWIS PUBLISHERS PI BOCA RATON PA 2000 CORPORATE BLVD, NW, BOCA RATON, FL 33431 USA SN 0191-9512 J9 OZONE-SCI ENG JI Ozone-Sci. Eng. PD FEB PY 2001 VL 23 IS 1 BP 77 EP 87 DI 10.1080/01919510108961990 PG 11 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 407KY UT WOS:000167271800007 ER PT J AU Diehl, SR White, PS AF Diehl, SR White, PS TI Cambridge Healthtech Institute's Third Annual Conference on Human Genetic Variation - 16-18 October 2000, Philadelphia, Pennsylvania, USA SO PHARMACOGENOMICS LA English DT Editorial Material DE gene mapping; genetic disease; genetic epidemiology; linkage disequilibrium; SNP discovery; SNP genotyping; SNP scoring AB A major goal of pharmacogenomics is to identify the human genetic variation that influences susceptibility to complex diseases. Recently, theoretical statistical analyses have suggested that genes for complex diseases may be found by linkage disequilibrium (i.e., association). Single nucleotide polymorphism (SNP) susceptibility alleles for common diseases can occur at high frequencies in various populations and, thus, have a major impact on morbidity and mortality. To be successful, SNP mapping studies require successful teamwork, integrating clinicians, epidemiologists, molecular genetics experts, laboratory automation engineers, bioinformatics and database experts. New statistical methods are also developing rapidly and promise to further increase the power of these studies. A recent conference on human genetic variation provided an opportunity for experts in all of these disciplines to exchange ideas. At present, great technological challenges need to be overcome in order to increase the throughput greatly while lowering cost and still maintaining high accuracy for SNP genotyping. Although this approach is relatively new (at least on the scale now being contemplated), the large payoffs anticipated to accrue from the successful mapping of SNPs in disease genes has led the area to be very strongly supported by both public and private funding sources. The potential payoff for improving disease diagnosis and therapeutic efficacy, with better avoidance of adverse events based on SNP associations, is providing a tremendous incentive to move this effort forward at an ever-accelerating pace. C1 NIDCR, Craniofacial Epidemiol & Genet Branch, NIH, Bethesda, MD 20892 USA. Los Alamos Natl Lab, Biosci Div, Ctr Human Genome Studies, Los Alamos, NM 87545 USA. RP Diehl, SR (reprint author), NIDCR, Craniofacial Epidemiol & Genet Branch, NIH, Natcher Bldg Rm 4AS-43G,45 Ctr Dr, Bethesda, MD 20892 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU ASHLEY PUBLICATIONS LTD PI LONDON PA UNITEC HOUSE, 3RD FL, 2 ALBERT PLACE FINCHLEY CENTRAL, LONDON N3 1QB, ENGLAND SN 1462-2416 J9 PHARMACOGENOMICS JI Pharmacogenomics PD FEB PY 2001 VL 2 IS 1 BP 79 EP 84 DI 10.1517/14622416.2.1.79 PG 6 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 499NJ UT WOS:000172577000009 PM 11258201 ER PT J AU Stromberg, MF Mackler, SA Volpicelli, JR O'Brien, CP Dewey, SL AF Stromberg, MF Mackler, SA Volpicelli, JR O'Brien, CP Dewey, SL TI The effect of gamma-vinyl-GABA on the consumption of concurrently available oral cocaine and ethanol in the rat SO PHARMACOLOGY BIOCHEMISTRY AND BEHAVIOR LA English DT Article DE GABA; gamma-vinyl-GABA; ethanol; cocaine ID NUCLEUS-ACCUMBENS DOPAMINE; SELF-ADMINISTERED COCAINE; DISCRETE TRIALS PROCEDURE; VENTRAL TEGMENTAL AREA; DELIVERED COCAINE; TRANSAMINASE INHIBITOR; ALCOHOL DEPENDENCE; VOLUNTARY ALCOHOL; INDUCED INCREASES; AGONIST BACLOFEN AB It has frequently been reported that a high percentage of individuals, identified as either alcohol- or cocaine-dependent, concurrently abuse both drugs. The experiments reported here represent a continuing effort to develop an animal model to predict the effects of a potential pharmacotherapeutic agent on concurrently available oral ethanol and cocaine. These experiments utilized drinkometer circuitry to assess the effects of gamma-vinyl-GABA (GVG), a gamma -aminobutyric acid (GABA) transaminase inhibitor, on the consumption and temporal pattern of responses for orally self-administered ethanol and cocaine. The results of these experiments showed that GVG, at doses of 100, 200 and 300 mg/kg, reduced both ethanol and cocaine consumption in a dose-related manner. When compared to vehicle, GVG at all doses significantly reduced ethanol consumption while consumption of cocaine was significantly reduced only at 300 mg/kg. This is consistent with data showing that GVG reduces consumption of these drugs when administered alone and data showing that GVG is more potent in reducing ethanol-induced compared to cocaine-induced extracellular dopamine in the nucleus accumbens. Analysis of the temporal pattern of drinking across the session suggests that GVG's effects are due to a disruption of the reinforcing properties of ethanol and cocaine rather than a more general reduction in motor behavior. These data suggest that GVG has potential for clinical use in populations that abuse either alcohol or cocaine alone or in combination. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Univ Penn, Dept Psychiat, Ctr Studies Addict, Philadelphia, PA 19104 USA. Univ Penn, Dept Med, Philadelphia, PA USA. Univ Penn, Dept Pharmacol, Philadelphia, PA USA. Philadelphia VAMC, Philadelphia, PA USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Stromberg, MF (reprint author), Univ Penn, Dept Psychiat, Ctr Studies Addict, 3900 Chestnut St, Philadelphia, PA 19104 USA. EM stromberg@research.trc.upenn.edu FU NIAAA NIH HHS [AA00228] NR 44 TC 46 Z9 47 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0091-3057 J9 PHARMACOL BIOCHEM BE JI Pharmacol. Biochem. Behav. PD FEB PY 2001 VL 68 IS 2 BP 291 EP 299 DI 10.1016/S0091-3057(00)00456-1 PG 9 WC Behavioral Sciences; Neurosciences; Pharmacology & Pharmacy SC Behavioral Sciences; Neurosciences & Neurology; Pharmacology & Pharmacy GA 418GK UT WOS:000167882400014 PM 11267634 ER PT J AU Soneda, N de la Rubia, TD AF Soneda, N de la Rubia, TD TI Migration kinetics of the self-interstitial atom and its clusters in bce Fe SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID X-RAY SCATTERING; DISPLACEMENT CASCADES; COMPUTER-SIMULATION; MOLECULAR-DYNAMICS; DEFECT PRODUCTION; ALPHA-FE; METALS; IRON; IRRADIATION; MECHANISM AB Self-interstitial atoms (SIAs) and SIA clusters are produced in displacement cascades during irradiation of a material with high-energy particles. The migration kinetics of such defects are a critical factor in controlling microstructure evolution and the ensuing changes in mechanical properties. In this study, extensive molecular dynamics (MD) simulations were performed on the diffusion of the SIA and its clusters in bcc Fe. Diffusivities were calculated for various SIA cluster sizes. It was found that, although the diffusivity itself decreases as the SIA cluster size increases, their activation energy for migration is very small and does not increase with size, in contrast with previous assumptions. Based on previous results obtained by Wirth et al. and the current calculations, we study the mechanism of single SIA diffusion by a kinetic Monte Carlo technique. The resulting model is consistent with experiments. An important conclusion of this study is that the 'effective' migration energy of the single SIA (0.17 eV in the present MD study) is smaller than the activation energy for stage I-E recovery. The proposed model explains all the details of the low temperature recovery stages, I-D and I-E, Of bcc Fe without the need to invoke the existence of two independent interstitial configurations. C1 Cent Res Inst Elect Power Ind, Komae, Tokyo 2018511, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Soneda, N (reprint author), Cent Res Inst Elect Power Ind, 2-11-1 Iwato Kita, Komae, Tokyo 2018511, Japan. NR 27 TC 90 Z9 91 U1 1 U2 16 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD FEB PY 2001 VL 81 IS 2 BP 331 EP 343 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 403PW UT WOS:000167052500007 ER PT J AU Swadener, JG Pharr, GM AF Swadener, JG Pharr, GM TI Indentation of elastically anisotropic half-spaces by cones and parabolae of revolution SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID MODULUS; HARDNESS AB Indentation of ceramic materials with smooth indenters such as parabolae of revolution and spheres can be conducted in the elastic regime to relatively high loads. Ceramic single crystals thus provide excellent calibration media for load- and depth-sensing indentation testing; however, they are generally anisotropic and a complete elastic analysis is cumbersome. This study presents a simplified procedure for the determination of the stiffness of contact for the indentation of an anisotropic half-space by a rigid frictionless parabola of revolution which, to first order, approximates spherical indentation. Using a similar approach, a new procedure is developed for analysing conical indentation of anisotropic elastic media. For both indenter shapes, the contact is found to be elliptical, and equations are determined for the size, shape and orientation of the ellipse and the indentation modulus. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. RP Swadener, JG (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008,MS-6116, Oak Ridge, TN 37831 USA. OI Swadener, John G/0000-0001-5493-3461 NR 16 TC 102 Z9 102 U1 0 U2 16 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD FEB PY 2001 VL 81 IS 2 BP 447 EP 466 PG 20 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 403PW UT WOS:000167052500014 ER PT J AU Jia, QX Lu, P AF Jia, QX Lu, P TI Microstructure of heteroepitaxially grown RuO2 thin films on MgO by pulsed-laser deposition SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; RUTHENIUM DIOXIDE FILMS; EPITAXIAL-GROWTH AB Conductive ruthenium oxide (RuO2) thin films with a room-temperature resistivity of 35 mu Omega cm and a residual resistivity ratio above 5 have been heteroepitaxially grown on MgO(100) substrates by pulsed-laser deposition. The heteroepitaxial growth of RuO2 on MgO is confirmed by both the strong in-plane and the strong out-of-plane orientation of the film with respect to major axes of the substrate. The orientation relationship between the RuO2 film and the MgO substrate, deduced from both X-ray and electron diffraction, is (110)(RuO2)\\(100)(MgO) and [001](RuO2)\\[011](MgO) (and [(1) over bar 10](RuO2)\\[0 (1) over bar(1) over bar](MgO)). High-resolution electron microscopy reveals that the epitaxial RuO2 film contains two variants that are consistent with the X-ray diffraction measurement. C1 Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM USA. New Mexico Inst Min & Technol, Dept Mat Sci & Engn, Socorro, NM 87801 USA. RP Jia, QX (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Mail Stop K763, Los Alamos, NM USA. RI Jia, Q. X./C-5194-2008 NR 13 TC 1 Z9 1 U1 1 U2 6 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD FEB PY 2001 VL 81 IS 2 BP 141 EP 149 DI 10.1080/13642810108216531 PG 9 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 403QF UT WOS:000167053400003 ER PT J AU Stishov, SM AF Stishov, SM TI On quantum effects in condensed matter at high pressures SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID X-RAY-DIFFRACTION; KINETIC-ENERGY; STATE; EQUATION; HYDROGEN; DIAMOND; HE-4 AB Experimental data on the influence of quantum effects on the equation of state and melting at high pressures are reviewed. It is shown that the quantum isotopic effects tend to increase upon compression of substances with predominately Coulomb interaction, whereas compression of the van der Waals substances reveals the opposite trend. 'Cold' melting of 'Coulomb' substances at high pressures is discussed. C1 Russian Acad Sci, Inst High Pressure Phys, Troitsk 142190, Moscow Region, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Stishov, SM (reprint author), Russian Acad Sci, Inst High Pressure Phys, Troitsk 142190, Moscow Region, Russia. NR 29 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD FEB PY 2001 VL 81 IS 2 BP 179 EP 191 DI 10.1080/13642810010009375 PG 13 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 403QF UT WOS:000167053400006 ER PT J AU Grigull, S Ishimaru, M Nastasi, M Zorman, CA Mehregany, M AF Grigull, S Ishimaru, M Nastasi, M Zorman, CA Mehregany, M TI On the stability of beta-SiC with respect to chemical disorder induced by irradiation with energetic particles SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article ID SOLID-STATE AMORPHIZATION; INTERMETALLIC COMPOUNDS; ELECTRON-IRRADIATION; AMORPHOUS TRANSITION; ION-IMPLANTATION; CRYSTALLINE; TRANSFORMATION; CERAMICS; HYDROGEN; PHASE AB X-ray diffraction measurements of changes in the long-range structural order of beta -SiC thin films have been performed during irradiation with energetic ions at low temperature. The decrease in both the chemical and the topological order was analysed in situ using the superstructure (002) and the fundamental (004) reflections of the zincblende-type structure, in a dose range up to complete amorphization. The data indicate that the crystalline-to-amorphous transition is a continuous process rather than a sudden collapse of a defective crystal structure and that, in contrast with previous assumptions, beta -SiC remains stable with respect to amorphization up to a high degree of chemical disorder. C1 European Synchrotron Radiat Facil, F-38043 Grenoble, France. Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Case Western Reserve Univ, Dept Elect Engn & Comp Sci, Cleveland, OH 44106 USA. RP Grigull, S (reprint author), European Synchrotron Radiat Facil, BP 220, F-38043 Grenoble, France. EM grigull@esrf.fr NR 31 TC 4 Z9 4 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0950-0839 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD FEB PY 2001 VL 81 IS 2 BP 55 EP 61 DI 10.1080/09500830010010968 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 403PV UT WOS:000167052400001 ER PT J AU Kung, H Hirth, JP Foltyn, SR Arendt, PN Jia, QX Maley, MP AF Kung, H Hirth, JP Foltyn, SR Arendt, PN Jia, QX Maley, MP TI Dissociation of grain boundary dislocations in YBa2Cu3O7-delta-coated conductors SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article ID COATED CONDUCTORS; NETWORK STRUCTURE; THICK-FILMS; BICRYSTALS; SUPERCONDUCTORS; TRANSPORT; TAPES AB The study reports the discovery of a new structure and spacing versus angle relation for a prevalent type of small-angle grain boundary in YBa2Cu3O7-delta (YBCO)-coated conductor films. Small-angle [001] tilt grain boundaries with (110) planes exhibit partial grain boundary dislocations (GBDs) separated by stacking faults. The dissociated grain boundary structures have twice the number of GBDs and shorter interdislocation core channel widths than Frank's geometrical rule predicts. This will require a significant alteration of models of supercurrent flow through arrays of small-angle grain boundaries in YBCO coated conductors. A thorough analysis of the stacking fault energy has been conducted based on the basis of anisotropic elasticity. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Kung, H (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 19 TC 16 Z9 16 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0950-0839 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD FEB PY 2001 VL 81 IS 2 BP 85 EP 93 DI 10.1080/09500830010012506 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 403PV UT WOS:000167052400005 ER PT J AU Ruhlander, M Soukoulis, CM AF Ruhlander, M Soukoulis, CM TI The probability distribution of the conductance at the mobility edge SO PHYSICA B LA English DT Article; Proceedings Paper CT Symposium on Wave Propagation and Electronic Structure in Disordered Systems held in honor of E N Economous 60th Birthday CY JUN 15-17, 2000 CL IRAKLION, GREECE DE conductance; mobility edge; localization; metal-insulator transition; disorder ID LOCALIZATION AB The probability distribution of the conductance p(g) of disordered 2d and 3d systems is calculated by transfer matrix techniques. As expected, p(g) is Gaussian for extended states while for localized states it is log-normal. We find that at the mobility edge p(g) is highly asymmetric and universal. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Crete, Res Ctr Crete, Dept Phys, ISEL,FORTH, Heraklion 71110, Crete, Greece. Iowa State Univ, Dept Phys & Astron, Ames Lab, Ames, IA 50012 USA. RP Soukoulis, CM (reprint author), Univ Crete, Res Ctr Crete, Dept Phys, ISEL,FORTH, POB 1572, Heraklion 71110, Crete, Greece. RI Soukoulis, Costas/A-5295-2008 NR 9 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD FEB PY 2001 VL 296 IS 1-3 BP 32 EP 35 DI 10.1016/S0921-4526(00)00774-2 PG 4 WC Physics, Condensed Matter SC Physics GA 418EL UT WOS:000167877900005 ER PT J AU Busch, K Soukoulis, CM AF Busch, K Soukoulis, CM TI Energy-density CPA: a new effective medium theory for classical waves SO PHYSICA B LA English DT Article; Proceedings Paper CT Symposium on Wave Propagation and Electronic Structure in Disordered Systems held in honor of E N Economous 60th Birthday CY JUN 15-17, 2000 CL IRAKLION, GREECE DE transport properties; disordered medium; localization; light ID STRONGLY SCATTERING MEDIA; TRANSPORT-PROPERTIES; LOCALIZATION; LIGHT; PROPAGATION; SYSTEMS; SPEED AB We present the framework of an effective medium theory to calculate the transport properties of classical waves in disordered media, Busch and Soukoulis (Phys. Rev. Lett. 75 (1995) 3442). It is based on the principle that the wave energy density should be uniform when averaged over length scales larger than the size of the basic scattering unit and can therefore, be applied to electromagnetic, Busch and Soukoulis (Phys. Rev. B 54 (1996) 893); Kirchner et al. (Phys. Rev. B 57 (1998) 277) as well as elastic waves. Kafesaki and Economou (Europhys. Lett. 37 (1997) 7), Soukoulis et al. (Phys. Rev. Lett. 82 (1999) 2000). Within this energy-density CPA (ECPA) resonant scattering of the individual scatterer is treated exactly, and by using a coated sphere as the basic scattering unit, multiple scattering contributions are incorporated in a mean-field sense. In the long-wavelength limit we are able to calculate effective material properties exactly. Results for the mean-free path, transport velocity, and the diffusion coefficient for finite frequencies agree qualitatively and quantitatively with experiment for all densities of scatterers, Busch and Soukoulis (Phys. Rev. B 54 (1996) 893); Gomez et al. (Europhys. Lett. 48 (1999) 22). A study of the localization parameter (k) over barl(s) within this effective-medium approach allows to identify the optimal parameters for localization, Kirchner et al. (Phys. Rev. B 57 (1998) 277). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Karlsruhe, Inst Theorie Kondensierten Mat, D-76128 Karlsruhe, Germany. Iowa State Univ Sci & Technol, Dept Phys, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Busch, K (reprint author), Univ Karlsruhe, Inst Theorie Kondensierten Mat, POB 6980, D-76128 Karlsruhe, Germany. RI Soukoulis, Costas/A-5295-2008 NR 22 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD FEB PY 2001 VL 296 IS 1-3 BP 56 EP 61 DI 10.1016/S0921-4526(00)00779-1 PG 6 WC Physics, Condensed Matter SC Physics GA 418EL UT WOS:000167877900010 ER PT J AU Pantelides, ST Di Ventra, M Lang, ND AF Pantelides, ST Di Ventra, M Lang, ND TI Molecular electronics by the numbers SO PHYSICA B LA English DT Article; Proceedings Paper CT Symposium on Wave Propagation and Electronic Structure in Disordered Systems held in honor of E N Economous 60th Birthday CY JUN 15-17, 2000 CL IRAKLION, GREECE DE molecular electronics; band structure; transport; differential resistance ID CONDUCTANCE; RESISTANCE; DEVICE AB The paper gives an overview of recent work by the authors on first-principles, parameter-free calculations of electronic transport in molecules in the context of experimental measurements of current-voltage (I-V) characteristics of several molecules by Reed et al. The results show that the shape of I-V characteristics is determined by the electronic structure of the molecule in the presence of the external voltage whereas the absolute magnitude of the current is determined by the chemistry of individual atoms at the contacts. A three-terminal device has been modeled, showing gain. Finally, recent data that show large negative differential resistance and a peak that shifts substantially as a function of temperature have been accounted for. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37861 USA. IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. RP Pantelides, ST (reprint author), Vanderbilt Univ, Dept Phys & Astron, 221 Kirkland Hall, Nashville, TN 37235 USA. RI Di Ventra, Massimiliano/E-1667-2011 OI Di Ventra, Massimiliano/0000-0001-9416-189X NR 12 TC 32 Z9 32 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD FEB PY 2001 VL 296 IS 1-3 BP 72 EP 77 DI 10.1016/S0921-4526(00)00782-1 PG 6 WC Physics, Condensed Matter SC Physics GA 418EL UT WOS:000167877900013 ER PT J AU Li, QM Ho, KM Soukoulis, CM AF Li, QM Ho, KM Soukoulis, CM TI Mode distribution in coherently amplifying random media SO PHYSICA B LA English DT Article; Proceedings Paper CT Symposium on Wave Propagation and Electronic Structure in Disordered Systems held in honor of E N Economous 60th Birthday CY JUN 15-17, 2000 CL IRAKLION, GREECE DE random laser; localization; disorder ID RANDOM LASER; SPONTANEOUS EMISSION; DISORDERED MEDIA; SCATTERING; LIGHT; LOCALIZATION; DYE; BACKSCATTERING; AMPLIFICATION; REFLECTION AB We investigate the statistics of lasing modes in a disordered one-dimensional active system. Dielectric scatters are randomly embedded in an amplifying medium to increase the optical length of photon. The lasing mode of each individual sample is obtained numerically by carefully locating the frequency and the threshold gain at which the reflection and the transmission coefficient first become divergent, a characteristic of the oscillation pole. As the density of scatters increases, the characteristic threshold gain for lasing decreases while the distribution of mode frequency broadens around the spontaneous emission frequency of the gain medium. The averaged gain threshold is indeed found to be proportional to the localization length, signifying the enhancement of light amplification due to multiple scattering. Interestingly. we find that the actual value of the gain threshold larger than previous theoretical predictions by a factor of 3-5, in agreement with a recent experiment. (C) 2001 Published by Elsevier Science B.V. C1 Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RP Soukoulis, CM (reprint author), Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RI Soukoulis, Costas/A-5295-2008 NR 25 TC 30 Z9 32 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD FEB PY 2001 VL 296 IS 1-3 BP 78 EP 84 DI 10.1016/S0921-4526(00)00783-3 PG 7 WC Physics, Condensed Matter SC Physics GA 418EL UT WOS:000167877900014 ER PT J AU Ma, XZ Soukoulis, CM AF Ma, XZ Soukoulis, CM TI Schrodinger equation with imaginary potential SO PHYSICA B LA English DT Article; Proceedings Paper CT Symposium on Wave Propagation and Electronic Structure in Disordered Systems held in honor of E N Economous 60th Birthday CY JUN 15-17, 2000 CL IRAKLION, GREECE DE transfer matrix; gain; disorder; non-hermitian systems ID RANDOM-MEDIA; LOCALIZATION; AMPLIFICATION; LIGHT; REFLECTION; ABSORPTION; SYMMETRY; GAIN AB We numerically investigate the solution of the Schrodinger equation in a one-dimensional system with gain. The gain is introduced by adding a positive imaginary potential in the system. We find that the time-independent solution gives that the amplification suppresses wave transmission at large gain. Solutions from the time-dependent equation clearly demonstrate that when gain is above a threshold value, the amplitude of the transmitted wave increases exponentially with time. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Ames Lab, USDOE, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP Soukoulis, CM (reprint author), Iowa State Univ Sci & Technol, Ames Lab, USDOE, Ames, IA 50011 USA. RI Soukoulis, Costas/A-5295-2008 NR 17 TC 13 Z9 13 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD FEB PY 2001 VL 296 IS 1-3 BP 107 EP 111 DI 10.1016/S0921-4526(00)00786-9 PG 5 WC Physics, Condensed Matter SC Physics GA 418EL UT WOS:000167877900017 ER PT J AU Wang, XS Li, QM Soukoulis, CM AF Wang, XS Li, QM Soukoulis, CM TI Scaling of the conductance in anisotropic 2d systems SO PHYSICA B LA English DT Article; Proceedings Paper CT Symposium on Wave Propagation and Electronic Structure in Disordered Systems held in honor of E N Economous 60th Birthday CY JUN 15-17, 2000 CL IRAKLION, GREECE DE conductance; localization; anisotropic systems; metal-to-insulator transition ID HALL PLATEAU TRANSITIONS; C-AXIS TRANSPORT; ANDERSON LOCALIZATION; MODEL; UNIVERSALITY AB We investigate the scaling of conductances in anisotropic two-dimensional systems. The conductance and its distribution in the two directions are found to be approximately the same, once the dimension of the system in each direction is chosen to be proportional to the localization length. At the localization-delocalization transition under a strong magnetic field, the geometrical mean of the conductance in the two directions is not universal. The distribution of conductances at the critical point also show distinctive features in the two directions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, US DOE, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. Univ Crete, Res Ctr, Heraklion 71110, Crete, Greece. Univ Crete, Dept Phys, Heraklion 71110, Crete, Greece. RP Soukoulis, CM (reprint author), Iowa State Univ, US DOE, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RI Soukoulis, Costas/A-5295-2008 NR 31 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD FEB PY 2001 VL 296 IS 1-3 BP 280 EP 288 DI 10.1016/S0921-4526(00)00811-5 PG 9 WC Physics, Condensed Matter SC Physics GA 418EL UT WOS:000167877900042 ER PT J AU Zheng, H Claus, H Chen, L Paulikas, AP Veal, BW Olsson, B Koshelev, A Hull, J Crabtree, GW AF Zheng, H Claus, H Chen, L Paulikas, AP Veal, BW Olsson, B Koshelev, A Hull, J Crabtree, GW TI Transport currents measured in ring samples: test of superconducting weld SO PHYSICA C LA English DT Article ID YBA2CU3O7-DELTA SINGLE-CRYSTALS; MELT-TEXTURED YBCO; PHYSICAL-PROPERTIES; GRAIN-BOUNDARIES; MICROSTRUCTURE; DEPENDENCE; RELAXATION; GROWTH AB The critical current densities in bulk melt-textured YBa2Cu3Ox and across superconducting "weld" joints are measured using scanning Hall probe measurements of the trapped magnetic field in ring samples. With this method, critical current densities are obtained without the use of electrical contacts. Large persistent currents are induced in ring samples at 77 K, after cooling in a 3 kG field. These currents can be determined from the magnetic field they produce. At 77 K a supercurrent exceeding 2000 A (about 10(4) A/cm(2)) was induced in a 2 cm diameter ring; this current produces a magnetic field exceeding 1.5 kG in the bore of the ring. We demonstrate that when a ring is cut, and the cut is repaired by a superconducting weld, the weld joint can transmit the same high supercurrent as the bulk. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci MSD223, Argonne, IL 60439 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RP Veal, BW (reprint author), Argonne Natl Lab, Div Mat Sci MSD223, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 19 TC 27 Z9 27 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD FEB 1 PY 2001 VL 350 IS 1-2 BP 17 EP 23 DI 10.1016/S0921-4534(00)01566-5 PG 7 WC Physics, Applied SC Physics GA 398GN UT WOS:000166748700004 ER PT J AU Ciftja, O AF Ciftja, O TI Theoretical estimates for the correlation energy of the unprojected composite fermion wave function SO PHYSICA E LA English DT Article DE quantum Hall effect; composite fermions; Laughlin states ID INCOMPRESSIBLE QUANTUM-FLUID; FILLED LANDAU-LEVEL; STATE AB The most prominent filling factors of the fractional quantum Hall effect are very well described by the Jain's microscopic composite fermion wave function. Through these wave functions, the composite fermion theory recovers the Laughlin's wave function as a special case and exposes itself to rigorous tests. Considering the system as being in the thermodynamic limit and using simple arguments, we give theoretical estimates for the correlation energy corresponding to all unprojected composite fermion wave functions in terms of the accurately known correlation energies of the Laughlin's wave function. The provided theoretical estimates are in very good agreement with available Monte Carlo data extrapolated to the thermodynamic limit. These results can be quite instructive to test the reliability and accuracy of different computational methods employed on the study of these phenomena. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Ciftja, O (reprint author), Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. NR 10 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD FEB PY 2001 VL 9 IS 2 BP 226 EP 230 DI 10.1016/S1386-9477(00)00198-3 PG 5 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 408UM UT WOS:000167346100002 ER PT J AU Baertschy, M Rescigno, TN Isaacs, WA Li, X McCurdy, CW AF Baertschy, M Rescigno, TN Isaacs, WA Li, X McCurdy, CW TI Electron-impact ionization of atomic hydrogen SO PHYSICAL REVIEW A LA English DT Article ID DIFFERENTIAL CROSS-SECTIONS; ASYMPTOTIC FORM; THRESHOLD; SCATTERING; PHOTOIONIZATION; E,2E AB Exterior complex scaling enables one to solve the time-independent Schrodinger equation for three charged particles without explicitly imposing the asymptotic boundary condition for three-body breakup. We have used this formalism to study electron-impact ionization of atomic hydrogen by directly solving for the radial components of the scattered wave on a complex, exterior scaled numerical grid. Computational procedures, presented briefly elsewhere [T. N. Rescigno, M. Baertschy, W. A. Isaacs, and C. W. McCurdy, Science 286, 2474 (1999)], are discussed here in greater detail and additional results are presented. Our method is limited only by the finite size of the grid and the number of partial-wave components retained in the expansion of the wave function and, unlike other methods that have been used to study ionization, involves no uncontrolled approximations. Our calculated triply differential cross sections at 17.6. 20, 25, and 30 eV are found to be in excellent agreement with recent measurements. C1 Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Comp Sci, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Phys Directorate, Livermore, CA 94550 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. RP Joint Inst Lab Astrophys, Boulder, CO 80309 USA. NR 44 TC 106 Z9 106 U1 4 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 022712 DI 10.1103/PhysRevA.63.022712 PG 19 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900062 ER PT J AU Diamant, R Huotari, S Hamalainen, K Sharon, R Kao, CC Deutsch, M AF Diamant, R Huotari, S Hamalainen, K Sharon, R Kao, CC Deutsch, M TI Structure of the W L alpha(1,2) x-ray spectrum SO PHYSICAL REVIEW A LA English DT Article ID FLUORESCENCE YIELDS; EMISSION-SPECTRA; COSTER-KRONIG; K-ALPHA; SYNCHROTRON PHOTOIONIZATION; L-SHELL; THRESHOLD; WIDTHS; SATELLITES; ELEMENTS AB The tungsten L alpha (1,2) x-ray spectrum was measured with high resolution using photoexcitation by monochromatized synchrotron radiation. The line splitting, widths, and relative intensities were determined from a phenomenological fit by five Voigt functions and compared with previous measurements. A fully split diagram and 5l(-1) spectator hole transition multiplets were calculated ab initio using the relativistic multiconfigurational Dirac-Fock method. Fits of various combinations of these multiplets to the measured spectrum show that the line shapes can be well accounted for by the fully split diagram transition 2p(3/2)(-1) --> 3d(3/2,5/2)(-1) alone, without invoking contributions from any spectator hole transition. C1 Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Deutsch, M (reprint author), Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. EM deutsch@mail.biu.ac.il RI Hamalainen, Keijo/A-3986-2010 OI Hamalainen, Keijo/0000-0002-9234-9810 NR 38 TC 14 Z9 14 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 022508 DI 10.1103/PhysRevA.63.022508 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900048 ER PT J AU Glover, TE Chin, AH Schoenlein, RW AF Glover, TE Chin, AH Schoenlein, RW TI High-order harmonic pulse broadening in an ionizing medium SO PHYSICAL REVIEW A LA English DT Article ID ELECTROMAGNETIC-FIELD; TUNNELING IONIZATION; ATTOSECOND PULSES; LASER-PULSES; GENERATION; TIME; RADIATION; PLASMAS; REGIME; GASES AB High-order harmonic pulse durations are measured using a laser and vacuum ultraviolet cross-correlation technique and the results are compared to theory. Harmonic purses generated using moderate laser intensity are well described by current models and demonstrate that harmonic pulses are temporally broadened when produced at laser intensities sufficiently high to ionize the medium. At even higher generating laser intensity, measured pulse durations are longer than simulated pulse durations. We consider dipole emission from ions and distortion of the spatial laser profile as possible causes for the discrepancy. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Adv Light Source Div, Berkeley, CA 94720 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Stanford Univ, WW Hansen Expt Phys Lab, Stanford, CA 94305 USA. RP Glover, TE (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Adv Light Source Div, Berkeley, CA 94720 USA. RI Schoenlein, Robert/D-1301-2014 OI Schoenlein, Robert/0000-0002-6066-7566 NR 34 TC 7 Z9 7 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 023403 DI 10.1103/PhysRevA.63.023403 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900072 ER PT J AU Johnson, WR Cheng, KT AF Johnson, WR Cheng, KT TI Strong nondipole effects in low-energy photoionization of the 5s and 5p subshells of xenon SO PHYSICAL REVIEW A LA English DT Article ID RANDOM-PHASE-APPROXIMATION; ANGULAR-DISTRIBUTION PARAMETERS; PHOTO-IONIZATION; MULTIPOLE CORRECTIONS; PHOTOELECTRONS; SHELLS; RETARDATION; NEON AB Large nondipole effects are predicted in the angular distribution of photoelectrons from the 5s and 5p subshells of xenon for photon energies below 200 eV. The nondipore parameter gamma (5s) exhibits a dispersion-curve variation near the first minimum of the 5s cross section at 35 eV, reaching a minimum value of -0.8 near 40 eV. Rapid Variation of gamma (5s) is also found near the second minimum of the 5s cross section at 150 eV, where gamma (5s) reaches a maximum value of 1.2. Smaller, but significant, nondipole effects are also found in the parameter zeta (5p) = gamma (5p) + 3 delta (5p), which has a maximum value of 0.15 near 50 eV, and a second maximum value of 0.18 near 160 eV. The higher energy maxima in gamma (5s) and zeta (5p) arise from correlation enhanced by shape resonances in the 4p --> f quadrupole photoionization channels. These predictions are based on relativistic random-phase approximation calculations in which excitations from 5p, 5s, 4d, 4p, and 4s subshells are coupled. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Johnson, WR (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. NR 20 TC 35 Z9 38 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 022504 DI 10.1103/PhysRevA.63.022504 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900044 ER PT J AU McCurdy, CW Horner, DA Rescigno, TN AF McCurdy, CW Horner, DA Rescigno, TN TI Practical calculation of amplitudes for electron-impact ionization SO PHYSICAL REVIEW A LA English DT Article ID NEAR-THRESHOLD; QUANTUM SCATTERING; ASYMPTOTIC FORM; CROSS-SECTIONS; HYDROGEN; MODELS; LAW AB An integral expression that is formally valid only for short-range potentials is applied to the problem of calculating the amplitude for electron-impact ionization. It is found that this expression provides a practical and accurate path to the calculation of singly differential cross sections for electron-impact ionization. Calculations are presented for the Temkin-Poet and collinear models for ionization of hydrogen by electron impact. An extension of the finite-element approach using the discrete-variable representation, appropriate for potentials with discontinuous derivatives like the Temkin-Poet interaction, is also presented. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94551 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP McCurdy, CW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 30 TC 45 Z9 45 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 022711 DI 10.1103/PhysRevA.63.022711 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900061 ER PT J AU Odero, DO Peacher, JL Schultz, DR Madison, DH AF Odero, DO Peacher, JL Schultz, DR Madison, DH TI Time-dependent treatment of electron-hydrogen scattering for higher angular momenta (L > 0) SO PHYSICAL REVIEW A LA English DT Article ID IMPACT IONIZATION; COUPLING METHOD; THRESHOLD; LATTICE AB The time-dependent approach to electron-atom scattering is emerging as an alternative to more conventional methods of treating atomic collisions. Solving the time-dependent Schrodinger equation directly has several very attractive features including a completely nonperturbative solution, dense representation of the nonphysical positive energy states, circumvention of the need to explicitly impose boundary conditions for ionization, and the convenience of being able to "watch" the electronic probability density evolve though the collision. Two principal approaches have so far been applied to treat electron-atom scattering, namely, the time-dependent close couping (TDCC) method and what we refer to as the time-dependent Hylleraas (TDH) method. The TDCC method solves coupled equations with two variables within a truncated infinite sum over individual angular momenta for each total angular momentum L of the system. In contrast, the TDH method avoids an infinite summation over the angular momenta of the individual electrons at the expense of solving a coupled equation with three variables for each L. The TDH method has previously been used for L = 0 only. An important question, therefore, concerns whether the TDH method would represent a numerical advantage over the TDCC method for higher L values. This issue is investigated in this paper. C1 Univ Missouri, Dept Phys, Rolla, MO 65409 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Odero, DO (reprint author), Univ Missouri, Dept Phys, Rolla, MO 65409 USA. NR 23 TC 4 Z9 4 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 022708 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900058 ER PT J AU Peet, VE Garrett, WR Shchemeljov, SV AF Peet, VE Garrett, WR Shchemeljov, SV TI Near-resonance three-photon excitation profiles in xenon with segmented conical beams SO PHYSICAL REVIEW A LA English DT Article ID ENHANCED MULTIPHOTON IONIZATION; 3RD-HARMONIC GENERATION; BESSEL BEAMS; SHIFTS AB Multiphoton ionization profiles in xenon under three-photon excitation by azimuthally segmented conical laser beams have been studied and analyzed on the basis of the interference-based cooperative shift of the atomic resonance line. Segmentation of the conical wave front with various geometrical slits reduces the possible three-photon azimuthal sub-beam combinations in the third order process and a principal (or "homogeneous") Lorentzian component can be selected from the overall excitation profile. This Lorentzian is identical to the pressure-broadened atomic line shifted by the cooperative shift. A possibility of controlling the nonlinear response by spatial selection of interacting waves in conical beams is discussed. C1 Univ Tartu, Inst Phys, EE-51014 Tartu, Estonia. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Peet, VE (reprint author), Univ Tartu, Inst Phys, Riia 142, EE-51014 Tartu, Estonia. RI Peet, Viktor/J-8588-2014 NR 16 TC 4 Z9 4 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 023804 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900102 ER PT J AU Thyssen, J Schwerdtfeger, P Bender, M Nazarewicz, W Semmes, PB AF Thyssen, J Schwerdtfeger, P Bender, M Nazarewicz, W Semmes, PB TI Quadrupole and hexadecapole couplings for I-127 in (LiI)-I-127 SO PHYSICAL REVIEW A LA English DT Article ID MEAN-FIELD; WAVE-FUNCTIONS; MICROWAVE DATA; NUCLEI; MOMENT; PARAMETRIZATION; DEFORMATIONS; IODIDE; MODEL AB The quadrupole and hexadecapole coupling constants for I-127 in LiI were determined from relativistic Dirac-Fock electronic structure and self-consistent nuclear structure calculations. While the calculated quadrupole coupling constant agrees with the experimental value, the predicted hexadecapole coupling constant ranges between +6 and +20 mHz, which is of opposite sign and about three orders of magnitude smaller than the value deduced from recent high resolution radio-frequency molecular beam measurements [J. Cederberg, D. Olson, A. Nelson, D. Laine, P. Zimmer, M. Welge, M. Feig, T. Hoft, and N. London, J. Chem. Phys. 110, 2431 (1999)]. C1 Univ Auckland, Dept Chem, Auckland, New Zealand. Univ So Denmark, Dept Chem, DK-5230 Odense M, Denmark. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. Tennessee Technol Univ, Dept Phys, Cookeville, TN 38505 USA. RP Univ Auckland, Dept Chem, Private Bag 92019, Auckland, New Zealand. EM schwerd@ccu1.auckland.ac.nz; witek@utk.edu RI Bender, Michael/B-9004-2009 NR 58 TC 10 Z9 10 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 022505 DI 10.1103/PhysRevA.63.022505 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900045 ER PT J AU Wargelin, BJ Kahn, SM Beiersdorfer, P AF Wargelin, BJ Kahn, SM Beiersdorfer, P TI Dielectronic satellite contributions to NeVIII and NeIX K-shell spectra SO PHYSICAL REVIEW A LA English DT Article ID BEAM ION-TRAP; HE-LIKE IONS; ELECTRON-IMPACT; CROSS-SECTIONS; POLARIZATION; LINES; EXCITATION; EMISSION; LIFETIME; LEVEL AB K alpha spectra of heliumlike neon and associated lithiumlike, berylliumlike, and boronlike satellite line emission have been observed with a high-resolution crystal spectrometer on the Lawrence Livermore Electron Beam Ion Trap. The KLL dielectronic recombination satellites were resolved from their He-like parent lines in electron energy space, and their wavelengths and resonance strengths measured. The wavelength measurements achieved a typical accuracy of a few m Angstrom, with two measurements accurate to better than one part in 10 000. By normalizing to the He-like resonance line, w, we measure Li-like satellite resonance strengths that are 10% to 46% lower than predicted by theoretical models. The wavelengths and relative strengths of Be-like KLL satellites were also measured, and absolute strengths were obtained by normalizing to the collisionally excited Li-like qr satellite blend. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. NR 31 TC 19 Z9 20 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD FEB PY 2001 VL 63 IS 2 AR 022710 DI 10.1103/PhysRevA.63.022710 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 400JF UT WOS:000166867900060 ER PT J AU Alekseev, PA Nefeodova, EV Staub, U Mignot, JM Lazukov, VN Sadikov, IP Soderholm, L Wassermann, SR Paderno, YB Shitsevalova, NY Murani, A AF Alekseev, PA Nefeodova, EV Staub, U Mignot, JM Lazukov, VN Sadikov, IP Soderholm, L Wassermann, SR Paderno, YB Shitsevalova, NY Murani, A TI Low-energy magnetic response and Yb valence in the Kondo insulator YbB12 SO PHYSICAL REVIEW B LA English DT Article ID INELASTIC NEUTRON-SCATTERING; SEMICONDUCTOR YBB12; SINGLE-CRYSTAL; CE3BI4PT3; GAP; EXCITATIONS AB X-ray absorption and high-resolution inelastic neutron-scattering experiments on the Kundo insulator YbB12 are reported. The ytterbium L-3-edge spectrum consists of a single white line with no observable temperature dependence between 10 and 295 K, indicating that the Yb valence is closer to 3+ than was concluded from previous high-resolution photoemission and XPS results. The neutron measurements confirm the existence of a gap in the magnetic excitation spectrum for T=5 K, and show that its gradual suppression as temperature increases is due to thr appearance of an extra quasielastic component in the: magnetic dynamical response. C1 Russian Res Ctr, Kurchatov Inst, Moscow 123182, Russia. Paul Scherrer Inst, Swiss Light Source, CH-5232 Villigen, Switzerland. CEA Saclay, CNRS, Lab Leon Brillouin, F-91191 Gif Sur Yvette, France. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. NASU, Inst Problems Mat Sci, UA-252142 Kiev, Ukraine. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. RP Alekseev, PA (reprint author), Russian Res Ctr, Kurchatov Inst, Moscow 123182, Russia. RI Mignot, Jean-Michel/A-8305-2008; Staub, Urs/C-4914-2015 OI Mignot, Jean-Michel/0000-0001-8503-6712; NR 22 TC 17 Z9 17 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 FEB 1 PY 2001 VL 63 IS 6 AR 064411 DI 10.1103/PhysRevB.63.064411 PG 6 WC Physics, Condensed Matter SC Physics GA 401DG UT WOS:000166911400050 ER PT J AU Bakulin, AS Overhauser, AW Kaiser, H Werner, SA Fernandez-Baca, JA Smith, HG AF Bakulin, AS Overhauser, AW Kaiser, H Werner, SA Fernandez-Baca, JA Smith, HG TI Phonon dispersion of indium along [111] SO PHYSICAL REVIEW B LA English DT Article ID DYNAMIC PSEUDOPOTENTIAL THEORY; METALS AB The phonon spectrum of indium along [111], measured by inelastic neutron scattering, is reported. The two shear modes at the zone-boundary point (1/2, 1/2, 1/2) are split slightly ton account of a 7.5% tetragonal distortion). They have very low frequencies, similar to0.7 and 1.0 THz, compared to the longitudinal mode, similar to3.4 THz. These measurements verify the theoretical dispersion predicted by the dynamic pseudopotential theory of phonons for free-electron-like metals. C1 Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Univ Missouri, Res Reactor Ctr, Columbia, MO 65211 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Bakulin, AS (reprint author), Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 5 TC 3 Z9 3 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2001 VL 63 IS 5 AR 052301 DI 10.1103/PhysRevB.63.052301 PG 3 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600009 ER PT J AU Bao, W Lacerda, AH Thompson, JD Honig, JM Metcalf, P AF Bao, W Lacerda, AH Thompson, JD Honig, JM Metcalf, P TI Phase transitions in a magnetic field in V2-yO3 (y=0 and 0.04) SO PHYSICAL REVIEW B LA English DT Article ID METAL-INSULATOR TRANSITIONS; SPIN-ORBITAL MODEL; SINGLE-CRYSTALS; V2O3; SCATTERING; DEGENERACY; EXCHANGE; SYSTEMS; ORDER; STATE AB The effect of a magnetic field on the two long-range-ordered magnetic phases, the collinear insulating antiferromagnetic (AFI) and the incommensurate metallic transverse spin density wave (SDW), is investigated for the vanadium sesquioxide system. A field of 18 T has little effect on the AFI phase of a nominal V2O3 sample. The transverse SDW phase of V1.96O3 can be suppressed by a 4.6(3)-T magnetic field applied in the plane of spiraling spins, while the same magnetic field applied along the spiral axis has little effect on the SDW phase. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. RP Bao, W (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Bao, Wei/E-9988-2011 OI Bao, Wei/0000-0002-2105-461X NR 45 TC 2 Z9 2 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 FEB 1 PY 2001 VL 63 IS 5 AR 052410 PG 4 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600019 ER PT J AU Butler, WH Zhang, XG Schulthess, TC MacLaren, JM AF Butler, WH Zhang, XG Schulthess, TC MacLaren, JM TI Spin-dependent tunneling conductance of Fe vertical bar MgO vertical bar Fe sandwiches SO PHYSICAL REVIEW B LA English DT Article ID INITIO MOLECULAR-DYNAMICS; TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; ELECTRONIC-STRUCTURE; JUNCTIONS; METALS; FILMS; BULK; CAO AB We present first-principles based calculations of the tunneling conductance and magnetoconductance of epitaxial Fe(100)\MgO(100)\Fe(100) sandwiches. Our results indicate that tunneling is much more interesting and complicated than the simple barrier model used previously. We obtain the following general results: (1) Tunneling conductance depends strongly on the symmetry of the Bloch states in the electrodes and of the evanescent states in the barrier layer. (2) Bloch states of different symmetry decay at different rates within the barrier. The decay rate is determined by the complex energy bands of the same symmetry in the barrier. (3) There may be quantum interference between the decaying states in the barrier. This leads to an oscillatory dependence of the tunneling current on kll and a damped oscillatory dependence on barrier thickness. (4) Interfacial resonance states can allow particular Bloch states to tunnel efficiently through the barrier. For Fe(100)(MgO(100)\Fe(100) our calculations indicate that quite different tunneling mechanisms dominate the conductance in the two spin channels. In the majority channel the conductance is primarily via Bloch electrons with small transverse momentum. One particular state with Delta (1) symmetry is able to effectively couple from the Fe into the MgO. In the minority channel the conductance is primarily through interface resonance states especially for thinner layers. We predict a large magnetoresistance that increases with barrier thickness. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Tulane Univ, Dept Phys, New Orleans, LA 70018 USA. RP Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 26 TC 1198 Z9 1210 U1 5 U2 32 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 FEB 1 PY 2001 VL 63 IS 5 AR 054416 DI 10.1103/PhysRevB.63.054416 PG 12 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600069 ER PT J AU Dai, PC Mook, HA Hunt, RD Dogan, F AF Dai, PC Mook, HA Hunt, RD Dogan, F TI Evolution of the resonance and incommensurate spin fluctuations in superconducting YBa2Cu3O6+x SO PHYSICAL REVIEW B LA English DT Review ID HIGH-TEMPERATURE SUPERCONDUCTORS; T-J MODEL; COPPER-OXIDE SUPERCONDUCTORS; NEUTRON-SCATTERING; MAGNETIC FLUCTUATIONS; CUPRATE SUPERCONDUCTORS; DYNAMIC SUSCEPTIBILITY; ELECTRONIC-STRUCTURE; CONDENSATION ENERGY; PAIRING MECHANISM AB Polarized and unpolarized neutron triple-axis spectrometry was used to study the dynamical magnetic susceptibility chi"(q,omega) as a function of energy ((h) over bar omega) and wave vector (q) in a wide temperature range for the bilayer superconductor YBa2Cu3O6+x with oxygen concentrations, x, of 0.45, 0.5, 0.6, 0.7, 0.8, 0.93, and 0.95, The most prominent features in the magnetic spectra include a spin gap in the superconducting state, a pseudogap in the normal state, the much-discussed resonance, and incommensurate spin fluctuations below the resonance. We establish the doping dependence of the spin gap in the superconducting state, the resonance energy, and the incommensurability of the spin fluctuations. The magnitude of the spin gap (E-sg) up to the optimal doping is proportional to the superconducting transition temperature T-c with E-sg/k(B)T(c)=3.8. The resonance, which exists exclusively below T-c for highly doped YBa2Cu3O6+x with x = 0.93 and 0.95, appears above T-c for underdoped compounds with x less than or equal to0.8. The resonance energy (E-r) also scales with k(B)T(c), but saturates at E(r)approximate to 40 meV for x close to 0.93. The incommensurate spin fluctuations at energies below the resonance have structures similar to that of the single-layer superconducting La2-xSrxCuO4. However, there are also important differences. While the incommensurability (delta) of the spin fluctuations in La2-xSrxCuO4 is proportional to T-c for the entire hole-doping range up to the optimal value, the incommensurability in YBa2Cu3O6+x increases with T-c for low-oxygen doping and saturates to delta =0.1 for x greater than or equal to0.6. In addition, the incommensurability decreases with increasing energy close to the resonance. Finally, the incommensurate spin fluctuations appear above T-c in underdoped compounds with x less than or equal to0.6 but for highly doped materials they are only observed below T-c. We discuss in detail the procedure used for separating the magnetic scattering from phonon and other spurious effects. In the comparison of our experimental results with various microscopic theoretical models, particular emphasis was made to address the similarities and differences in the spin fluctuations of the two most studied superconductors. Finally, we briefly mention recent magnetic-field-dependent studies of the spin fluctuations and discuss their relevance in understanding the microscopic origin of the resonance. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA. RP Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. EM daip@ornl.gov RI Dai, Pengcheng /C-9171-2012 OI Dai, Pengcheng /0000-0002-6088-3170 NR 105 TC 249 Z9 253 U1 1 U2 18 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 FEB 1 PY 2001 VL 63 IS 5 AR 054525 DI 10.1103/PhysRevB.63.054525 PG 20 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600120 ER PT J AU Feng, Y Dobrotvorska, MV Anderegg, JW Olson, CG Lynch, DW AF Feng, Y Dobrotvorska, MV Anderegg, JW Olson, CG Lynch, DW TI Fe-3s core-level splitting and local magnetism in Fe2VAl SO PHYSICAL REVIEW B LA English DT Article ID X-RAY PHOTOEMISSION; ELECTRONIC-STRUCTURE; 3S PHOTOEMISSION; FE; MULTIPLET; SPECTRA; ALLOYS; COMPOUND; BEHAVIOR; MOMENTS AB X-ray and soft x-ray photoelectron spectra were taken on Fe2VAl samples. The Fe-3s spectra show a shoulder on the higher binding energy side of the main peak, split by approximate to4.7 eV. Based on current understanding of core-level multiplet splitting in transition-metal compounds, we believe this is direct evidence of a local moment in Fe2VAl. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Feng, Y (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. 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 FEB 1 PY 2001 VL 63 IS 5 AR 054419 DI 10.1103/PhysRevB.63.054419 PG 5 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600072 ER PT J AU Gao, F Weber, WJ AF Gao, F Weber, WJ TI Atomic-scale simulation of 50 keV Si displacement cascades in beta-SiC SO PHYSICAL REVIEW B LA English DT Article ID IRRADIATION-INDUCED CRYSTALLINE; MOLECULAR-DYNAMICS; COMPUTER-SIMULATION; SILICON-CARBIDE; INDUCED AMORPHIZATION; AMORPHOUS TRANSITION; SINGLE-CRYSTALS; DEFECTS; METALS; IRON AB Molecular dynamics (MD) methods with a modified Tersoff potential have been used to simulate high-energy (50 keV) displacement cascades in beta -SiC. The results show that the cascade lifetime is very short, 10 times shorter than that in metals, and the surviving defects are dominated by C interstitials and vacancies, which is similar to behavior for 10 keV cascades in SiC. Antisite defects are generated on both sublattices. Although the total number of antisite defects remaining at the end of the cascade is smaller than that of Frenkel pairs, the number of Si antisites is larger than the number of Si interstitials. Most surviving defects are single interstitials and vacancies, and only 19% of the interstitial population is contained in clusters. The size of the interstitial clusters is small, and the largest cluster found, among all the cascades considered, contained only four interstitial atoms, which is significantly different behavior than obtained by MD simulations in metals. It is observed that all clusters are created by a quenched-in mechanism directly from the collisional phase of the cascade to their final arrangements. The initial Si recoil traveled about 65 nm on average, generating multiple subcascades and forming a dispersed arrangement in the cascade geometry. These results suggest that in-cascade or direct-impact amorphization in SiC does not occur with any high degree of probability during the cascade lifetime of Si cascades, even with high-energy recoils, consistent with previous experimental and MD observations. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gao, F (reprint author), Pacific NW Natl Lab, MS K8-93,POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; Gao, Fei/H-3045-2012 OI Weber, William/0000-0002-9017-7365; NR 31 TC 15 Z9 15 U1 1 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 FEB 1 PY 2001 VL 63 IS 5 AR 054101 PG 7 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600036 ER PT J AU Gorny, KR Vyaselev, OM Pennington, CH Hammel, PC Hults, WL Smith, JL Baumgartner, J Lemberger, TR Klamut, P Dabrowski, B AF Gorny, KR Vyaselev, OM Pennington, CH Hammel, PC Hults, WL Smith, JL Baumgartner, J Lemberger, TR Klamut, P Dabrowski, B TI Magnetic field independence of Cu(2) NMR spin-lattice relaxation rate in the normal state of optimally doped YBa2Cu3O7-delta SO PHYSICAL REVIEW B LA English DT Article ID LA1.85SR0.15CUO4; CU-63,CU-65; DECAY AB We report NMR measurements of Cu-63 spin-lattice relaxation rates, (63)(T1T)(-1), for magnetic fields of 0, 4, 8.8, and 14.8 T. The measurements were performed on four different samples within the family of near optimally doped YBa2Cu3O7-delta and for the range of temperatures above and below T-c. For each sample we consistently find that, in the normal state, Cu-63 spin-lattice relaxation rate is magnetic field independent and that field dependence develops only below T-c where (63)(T1T)(-1) curves "fan out." We describe in detail experimental methods enabling the high precision required in such measurements. C1 Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Russia. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. RP Gorny, KR (reprint author), Ohio State Univ, Dept Phys, 174 W 18th Ave, Columbus, OH 43210 USA. RI Hammel, P Chris/O-4845-2014 OI Hammel, P Chris/0000-0002-4138-4798 NR 18 TC 4 Z9 4 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 FEB 1 PY 2001 VL 63 IS 6 AR 064513 DI 10.1103/PhysRevB.63.064513 PG 6 WC Physics, Condensed Matter SC Physics GA 401DG UT WOS:000166911400083 ER PT J AU Huh, YM Ostenson, JE Borsa, F Kogan, VG Finnemore, DK Vietkin, A Revcolevschi, A Julien, MH AF Huh, YM Ostenson, JE Borsa, F Kogan, VG Finnemore, DK Vietkin, A Revcolevschi, A Julien, MH TI Reversible magnetization and superconducting-state thermodynamic parameters for underdoped La1.90Sr0.10CuO4 SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; SINGLE-CRYSTALS; II SUPERCONDUCTORS; FLUCTUATIONS; LA2-XSRXCUO4; LA1.9SR0.1CUO4; BI2SR2CACU2O8; ANISOTROPY; VORTICES; REGION AB Magnetization studies have been made of single-crystal La1.90Sr0.10CuO4 with H parallel toc in order to determine the magnitude of the flux expulsion and free energy in a material that has substantially less than optimal doping. Well above the superconducting transition temperature, the normal-state: magnetization exhibits a two-dimensional Heisenberg antiferromagnetic behavior. Below T-c, there is a large portion of the H-T plane where the sample shows: reversible behavior so that thermodynamic variables such as the free energy and the shape of the magnetization curves can be determined. At low temperature, the vortices have a well defined Abrikosov regime that transforms to two-dimensional fluctuation behavior at higher temperatures. The magnetization vs temperature curves show a unique crossing point at 22 K where the magnetization is independent of magnetic field. From this value of the crossing point, the effective layer spacing s is derived to be 1.6 nm compared to the CuO2 lattice spacing of 0.66 nm. The fluctuations are found to obey two-dimensional scaling in that M/(TH)(1/2) is a universal function of [T-T-c(H)]/(TH)(1/2). Below 12 K, the data fit the Hao-Clem theory rather well rind give kappa (c) values of about 175 and thermodynamic critical fields ranging from 112 mT at 12 K to 133 mT at 6 K. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Paris 11, Lab Physicochim Solides, Orsay, France. Univ Grenoble 1, Spectrometrie Phys Lab, F-38402 St Martin Dheres, France. RP Huh, YM (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. RI Julien, Marc-Henri/A-2352-2010 NR 30 TC 8 Z9 8 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2001 VL 63 IS 6 AR 064512 DI 10.1103/PhysRevB.63.064512 PG 6 WC Physics, Condensed Matter SC Physics GA 401DG UT WOS:000166911400082 ER PT J AU Jorgensen, JD Chmaissem, O Shaked, H Short, S Klamut, PW Dabrowski, B Tallon, JL AF Jorgensen, JD Chmaissem, O Shaked, H Short, S Klamut, PW Dabrowski, B Tallon, JL TI Magnetic ordering in the superconducting weak ferromagnets RuSr2GdCu2O8 and RuSr2EuCu2O8 SO PHYSICAL REVIEW B LA English DT Article ID COEXISTENCE; GD; HOMO6S8; CRYSTAL; ERRH4B4; RU AB Neutron powder-diffraction measurements for RuSr2GdCu2O8 and RuSr2EuCu2O8 show that both compounds, below their magnetic ordering temperatures of 133 and 120 K, respectively, have the same G-type antiferromagnetic structure in which Ru moments are antiparallel in all three crystallographic directions. The ferromagnetism in these compounds, which is clearly indicated by hysteresis loops, can be explained if the Ru moments are canted to give a net moment perpendicular to the c axis. In such a model, one would expect an induced ferromagnetic ordering of the magnetic Gd ions, which have large (similar to 7 mu (B)) moments, as a result of the net field at the Gd site, while Eu, being nonmagnetic, would exhibit no such response. The dramatically larger hysteresis loops for RuSr2GdCu2O8 compared to those for RuSr2EuCu2O8 are consistent with this hypothesis. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Sci & Technol Ctr Superconduct, Argonne, IL 60439 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Ind Res Ltd, Lower Hutt, New Zealand. Ben Gurion Univ Negev, Dept Phys, IL-84190 Beer Sheva, Israel. RP Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 25 TC 121 Z9 122 U1 0 U2 6 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 FEB 1 PY 2001 VL 63 IS 5 AR 054440 DI 10.1103/PhysRevB.63.054440 PG 5 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600093 ER PT J AU Kim, HJ Pruski, M Wiench, JW Jeong, DY Choh, SH AF Kim, HJ Pruski, M Wiench, JW Jeong, DY Choh, SH TI High-temperature phase transitions of LiRbSO4 studied by magic angle spinning and multiple quantum magic angle spinning NMR of Rb-87 SO PHYSICAL REVIEW B LA English DT Article ID QUADRUPOLAR NUCLEI; ROTATING SOLIDS; RBLISO4; SPECTRA; SPINS; MAS AB Solid-state nuclear magnetic resonance (NMR) of the Rb-87 has been employed to investigate the phase transitions in polycrystalline LiRbSO4. The spin-lattice relaxation time T-1 and the NMR line shape were measured using magic angle spinning (MAS) and multiple quantum magic angle spinning (MQMAS) methods between 373 and 488 K. The quadrupole coupling constant, Q(cc), the asymmetry parameter, eta (Q), and the isotropic chemical shift, delta (CS) were determined from the analysis of MAS and MQMAS spectra. The anomalies of Q(cc) near the IV-III phase transition were associated with the deformation of the local environment of the Rb ions in the crystal lattice. The measurements of the spin-lattice relaxation rate as a function of temperature and Larmor frequency showed the existence of a damped soft mode near the V-IV and IV-III phase transitions. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Korea Univ, Dept Phys, Seoul 136701, South Korea. RP Kim, HJ (reprint author), Pohang Univ Sci & Technol, Dept Chem, Pohang 790784, South Korea. NR 28 TC 2 Z9 2 U1 1 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 FEB 1 PY 2001 VL 63 IS 6 AR 064107 DI 10.1103/PhysRevB.63.064107 PG 6 WC Physics, Condensed Matter SC Physics GA 401DG UT WOS:000166911400030 ER PT J AU Lawrence, JM Riseborough, PS Booth, CH Sarrao, JL Thompson, JD Osborn, R AF Lawrence, JM Riseborough, PS Booth, CH Sarrao, JL Thompson, JD Osborn, R TI Slow crossover in YbXCu4 (X = AgCd, In, Mg, Tl, Zn) intermediate-valence compounds SO PHYSICAL REVIEW B LA English DT Article ID INELASTIC NEUTRON-SCATTERING; PERIODIC ANDERSON MODEL; RAY-ABSORPTION; TEMPERATURE-DEPENDENCE; YBINCU4; TRANSITION; PHOTOEMISSION; EXPANSION; DISORDER; BEHAVIOR AB We compare the results of measurements of the magnetic susceptibility chi (T), the linear coefficient of specific heat gamma (T) = C(T)/T, and 4f occupation number n(f)(T) for the intermediate-valence compounds YbXCu4 (X = Ag, Cd, In, Mg, Tl, Zn) to the predictions of the Anderson impurity model, calculated in the noncrossing approximation (NCA). The crossover from the low temperature Fermi-liquid state to the high-temperature local-moment state is substantially slower in the compounds than predicted by the NCA; this corresponds to the "protracted screening" recently predicted for the Anderson lattice. We present results for the dynamic susceptibility, measured through neutron-scattering experiments, to show that the deviations between theory and experiment are not due to crystal-field effects, and we present x-ray-absorption finestructure results that show the local crystal structure around the X atoms is well ordered, so that the deviations probably do not arise from Kondo disorder. The deviations may correlate with the background conduction electron density, as predicted for protracted screening. C1 Univ Calif Irvine, Irvine, CA 92697 USA. Temple Univ, Philadelphia, PA 19122 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Lawrence, JM (reprint author), Univ Calif Irvine, Irvine, CA 92697 USA. RI Osborn, Raymond/E-8676-2011; Riseborough, Peter/D-4689-2011; Booth, Corwin/A-7877-2008 OI Osborn, Raymond/0000-0001-9565-3140; NR 33 TC 57 Z9 57 U1 1 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 FEB 1 PY 2001 VL 63 IS 5 AR 054427 DI 10.1103/PhysRevB.63.054427 PG 9 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600080 ER PT J AU Levin, EM Pecharsky, AO Pecharsky, VK Gschneidner, KA AF Levin, EM Pecharsky, AO Pecharsky, VK Gschneidner, KA TI Transformations in the Gd-5(Si1.95Ge2.05) alloy induced by the temperature and magnetic-field cycling through the first-order magnetic-martensitic phase transition SO PHYSICAL REVIEW B LA English DT Article ID LONG-RANGE ORDER; ELECTRICAL-RESISTIVITY; GD-5(SI2GE2) AB Temperature dependencies of the de electrical resistivity, de magnetization, and heat capacity of virgin Gd-5(S1.95Ge2.05) samples and after they had been cycled through the first-order phase transition by varying temperature or magnetic field were studied. The virgin sample shows a transition from the low-temperature phase rr to the high-temperature, low-resistance phase beta'. After several temperature and/or magnetic field induced cycles of the Gd-5(Si1.95Ge2.05) alloy through the first-order phase transition, the alpha phase transforms to beta" where beta" is the high-resistance: phase. The dc magnetization and zero magnetic field heat capacity data indicate that the temperature of the alpha --> beta" phase transition is lower by similar to2 K relative to alpha --> beta'. while the electrical resistance shows similar to7 K temperature difference. The observed phenomena are discussed based on the mechanism of the simultaneous magnetic/crystallographic phase transition in Gd-5(SixGe4-x). C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 13 TC 67 Z9 68 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 FEB 1 PY 2001 VL 63 IS 6 AR 064426 DI 10.1103/PhysRevB.63.064426 PG 10 WC Physics, Condensed Matter SC Physics GA 401DG UT WOS:000166911400065 ER PT J AU Li, QA Gray, KE AF Li, QA Gray, KE TI Numerical method to test a theoretical model of the quantum interference effect in layered manganites SO PHYSICAL REVIEW B LA English DT Article AB A numerical method is provided to fit the experimental conductivity to the complicated conductivity expression for the quantum interference effect of Anderson localization. This method makes the fitting much easier so the theoretical model and experimental data match nicely. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Li, QA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Li, Qingan/L-3778-2013 NR 5 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 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2001 VL 63 IS 5 AR 052413 PG 4 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600022 ER PT J AU Lilly, MP Portier, F Hallock, RB AF Lilly, MP Portier, F Hallock, RB TI He-4 third-sound pulse collisions SO PHYSICAL REVIEW B LA English DT Article ID CLASSICAL WAVE LOCALIZATION; 3RD SOUND; SUPERFLUID HE-4; FILMS; 3RD-SOUND; THICKNESS; ARRAYS AB We investigate the behavior of pulses of He-4 third sound that propagate and collide on a glass substrate. Third sound is created by a thermal source and detected by evaporated metal superconducting transition-edge thermometers. Two thermal sources located symmetrically on either side of a detector allow third-sound pulses to be created, propagate through each other, and be detected. By varying the delay of the pulse launch between the two sources, the collision can be placed at an arbitrary position on the substrate. We present detailed observations of the evolution of the amplitudes of the third-sound pulses in collision. We also report measurements on the effect of the pulse collision on the propagation time of Hight of the third-sound pulses. Experimental results for the time of flight change induced by the collisions are compared with quantitative expectations based on the two fluid model and a stronger effect is observed than expected. C1 Univ Massachusetts, Dept Phys, Low Temp Phys Lab, Amherst, MA 01003 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Portier, Fabien/N-5131-2014 NR 29 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 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2001 VL 63 IS 5 AR 054524 PG 16 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600119 ER PT J AU Lobad, AI Averitt, RD Taylor, AJ AF Lobad, AI Averitt, RD Taylor, AJ TI Picosecond dynamics of the spin-lattice relaxation in La0.7Ca0.2MnO3: Magnetic-field dependence SO PHYSICAL REVIEW B LA English DT Article ID PEROVSKITES AB We have employer ultrafast optical pump-probe measurements at 1.5 eV to study the picosecond dynamics of the magnetic-field-induced metal-insulator (MI) transition in La0.7Ca0.3MnO3 thin films in fields up to 7 T. We show that field induced modification of the photoinduced dynamic spectral weight transfer (DSWT) is related to changes in the magnetic entropy. The magnetic-field-induced increase of the ferromagnetic-paramagnetic transition temperature is evident in the spin-lattice relaxation time and amplitude scaling of the DSWT. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lobad, AI (reprint author), Kirtland AFB DELS, Albuquerque, NM 87117 USA. NR 12 TC 21 Z9 21 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 FEB 1 PY 2001 VL 63 IS 6 AR 060410 DI 10.1103/PhysRevB.63.060410 PG 4 WC Physics, Condensed Matter SC Physics GA 401DG UT WOS:000166911400016 ER PT J AU Ovchinnikov, YN Wolf, SA Kresin, VZ AF Ovchinnikov, YN Wolf, SA Kresin, VZ TI Intrinsic inhomogeneities in superconductors and the pseudogap phenomenon SO PHYSICAL REVIEW B LA English DT Article ID T-C SUPERCONDUCTORS; OVERDOPED BI2SR2CACU2O8+DELTA; NORMAL-STATE; PRECURSOR; CRYSTALS; GAP AB High-T-c oxides are intrinsically inhomogeneous materials. The density of states is evaluated for such an inhomogeneous system, and it displays a gap structure above T-c(res) (pseudogap). Thus, the pseudogap phenomenon can be caused by an inhomogeneity of the metallic phase. As a result, the critical temperature is spatially dependent. Various types of nonuniform structure are described (inhomogeneous carrier distribution, nonuniform distribution of pair breakers). The transition to a dissipationless state (R=0) corresponds to the percolation threshold. C1 Russian Acad Sci, LD Landau Theoret Phys Inst, Moscow 117334, Russia. USN, Res Lab, Washington, DC 20375 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ovchinnikov, YN (reprint author), Russian Acad Sci, LD Landau Theoret Phys Inst, Moscow 117334, Russia. RI Wolf, Stuart/A-7513-2009 NR 48 TC 53 Z9 53 U1 1 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 FEB 1 PY 2001 VL 63 IS 6 AR 064524 DI 10.1103/PhysRevB.63.064524 PG 6 WC Physics, Condensed Matter SC Physics GA 401DG UT WOS:000166911400094 ER PT J AU Pagliuso, PG Thompson, JD Hundley, MF Sarrao, JL Fisk, Z AF Pagliuso, PG Thompson, JD Hundley, MF Sarrao, JL Fisk, Z TI Crystal structure and low-temperature magnetic properties of RmMIn3m+2 compounds (M = Rh or Ir; m=1,2; R = Sm or Gd) SO PHYSICAL REVIEW B LA English DT Article ID PHASE-DIAGRAM; NDIN3 AB We have synthesized the series of compounds RMIn5 and R2MIn8 in single crystal form, where R = Sm or Gd and M = Rh or Ir. These materials form in tetragonal derivatives of the Cu,Au structure RIn3. Measure ments of magnetic susceptibility, electrical resistivity, and low-temperature heat capacity are reported. These compounds order antiferromagnetically at low temperature (T-N<45 K) and their low-temperature magnetic properties remain nearly unaltered compared to their SmIn3 and GdIn3 cubic relatives. The present data are compared to the magnetic properties of the isostructural (Ce,Nd) (Rh,Ir)In-5 and (Ce,Nd)(2)(Rh,Ir)In-8 compounds, and the validity of de Gennes scaling as a function of rare earth in a given structure is discussed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Pagliuso, PG (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Pagliuso, Pascoal/C-9169-2012 NR 18 TC 53 Z9 53 U1 1 U2 10 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 FEB 1 PY 2001 VL 63 IS 5 AR 054426 DI 10.1103/PhysRevB.63.054426 PG 4 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600079 ER PT J AU Pennington, CH Yu, S Gorny, KR Buoni, MJ Hults, WL Smith, JL AF Pennington, CH Yu, S Gorny, KR Buoni, MJ Hults, WL Smith, JL TI Small tip angle NMR as a probe of electron-mediated nuclear spin-spin couplings in YBa2Cu3O7 SO PHYSICAL REVIEW B LA English DT Article ID LATTICE RELAXATION-RATE; CUPRATE SUPERCONDUCTORS; TRANSVERSE RELAXATION; MAGNETIC-RESONANCE; NEUTRON-SCATTERING; PLANAR OXYGEN; NORMAL-STATE; THETA-REDOR; MODEL; O-17 AB We develop the theory and application of small tip angle NMR techniques that can be used to measure couplings between nuclear spins and multiple neighboring spins. We employ the techniques to measure indirect (electron-mediated) nuclear spin-spin couplings between neighboring Cu-63,Cu-65 and O-17 nuclear spins in the high-temperature superconductor YBa2Cu3O7. Predictions for the values of these couplings can be obtained from the existing phenomenological models of electronic spin susceptibility chi (q,omega) and hyperfine couplings that have been used in attempts to understand the wide body of YBa2Cu3O7 NMR data gathered to date. We find that the measured couplings are incompatible with these models. C1 Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Pennington, CH (reprint author), Ohio State Univ, Dept Phys, 174 W 18th Ave, Columbus, OH 43210 USA. NR 58 TC 4 Z9 4 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2001 VL 63 IS 5 AR 054513 DI 10.1103/PhysRevB.63.054513 PG 13 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600108 ER PT J AU Prozorov, R Giannetta, RW Schlueter, J Kini, AM Mohtasham, J Winter, RW Gard, GL AF Prozorov, R Giannetta, RW Schlueter, J Kini, AM Mohtasham, J Winter, RW Gard, GL TI Unusual temperature dependence of the London penetration depth in all-organic beta ''-(ET)(2)SF5CH2CF2SO3 single crystals SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTOR BETA''-(BEDT-TTF)(2)SF5CH2CF2SO3; C-13 NMR; WAVE SUPERCONDUCTOR; BEDT-TTF; KAPPA-(ET)(2)CUBR; FIELD; STATE; HEAT AB The temperature dependence of the in-plane, lambda (parallel to)(T), and interplane, lambda (perpendicular to)(T). London penetration depth was measured in the metal-free all-organic superconductor beta"-(ET)(2)SF5CH2CF2SO3 (T(c)approximate to5.2 K). Delta lambda (parallel to)(T)proportional toT(3) up to 0.5 T-c, a power law previously observed only in materials thought to be p-wave superconductors. lambda (perpendicular to), is larger than the sample dimensions down to the lowest temperatures (0.35 K), implying an anisotropy of lambda (perpendicular to)/lambda (parallel to)approximate to 400-800. C1 Univ Illinois, Loomis Lab Phys, Urbana, IL 61801 USA. Argonne Natl Lab, Div Chem & Mat Sci, Argonne, IL 60439 USA. Portland State Univ, Dept Chem, Portland, OR 97207 USA. RP Prozorov, R (reprint author), Univ Illinois, Loomis Lab Phys, 1110 W Green St, Urbana, IL 61801 USA. RI Kini, Aravinda/F-4467-2012; Prozorov, Ruslan/A-2487-2008 OI Prozorov, Ruslan/0000-0002-8088-6096 NR 23 TC 13 Z9 13 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 FEB 1 PY 2001 VL 63 IS 5 AR 052506 DI 10.1103/PhysRevB.63.052506 PG 4 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600029 ER PT J AU Reichhardt, C Gronbech-Jensen, N AF Reichhardt, C Gronbech-Jensen, N TI Critical currents and vortex states at fractional matching fields in superconductors with periodic pinning SO PHYSICAL REVIEW B LA English DT Article ID JOSEPHSON-JUNCTION ARRAYS; FLUX-LINE-LATTICE; MOVING GLASS PHASE; DRIVEN LATTICES; ANTIDOT LATTICE; THIN-FILMS; IV CHARACTERISTICS; SUBMICRON HOLES; SQUARE LATTICE; MAGNETIC DOTS AB We study vortex states and dynamics in two-dimensional (2D) superconductors with periodic pinning at fractional submatching fields using numerical simulations. For square pinning arrays we show that ordered vortex states form at 1/1,1/2, and 1/4 filling fractions while only partially ordered states form at other tilling fractions, such as 1/3 and 1/5, in agreement with recent imaging experiments. For triangular pinning arrays we observe matching effects at filling fractions of 1/1, 6/7, 2/3, 1/3, 1/4, 1/6, and 1/7. For both square and triangular pinning arrays we also find that, for certain submatching fillings, vortex configurations depend on pinning strength. For weak pinning, ordering in which a portion of the vortices are positioned between pinning sites can occur. Depinning of the vortices at the matching fields, where the vortices are ordered, is elastic while at the incommensurate fields the motion is plastic. At the incommensurate fields, as the applied driving force is increased, there can be a transition to elastic flow where the vortices move along the pinning sites in 1D channels and a reordering transition to a triangular or distorted triangular lattice occurs. We also discuss the current-voltage curves and how they relate to the vortex ordering at commensurate and incommensurate fields. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RP Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. NR 62 TC 88 Z9 88 U1 0 U2 5 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 FEB 1 PY 2001 VL 63 IS 5 AR 054510 DI 10.1103/PhysRevB.63.054510 PG 10 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600105 ER PT J AU Rogacki, K Dabrowski, B Chmaissem, O Jorgensen, JD AF Rogacki, K Dabrowski, B Chmaissem, O Jorgensen, JD TI Increase of the superconducting T-c, irreversibility fields, and critical currents in tetragonal YBaSrCu3-xMoxO7+d SO PHYSICAL REVIEW B LA English DT Article ID PEROVSKITE AB Recently, we have investigated how the superconducting transition temperature T-c, critical currents j(c), and irreversibility fields B-irr, of compounds with multiple CuO2 planes depend on physical properties and structural features of the blocking layer. To modify conductivity of the CuO chains in the blocking layer and decrease anisotropy of the YBa2Cu3Oy compound, substitutions of Mo for Cu and Sr for Ba were done. Synthesis of the YBaSrCu3 - xMoxO7 + d compound was optimized for the highest T-c and j(c). Materials prepared in air at 960 degreesC and annealed in 250 atm. O-2 at around 650 degreesC are tetragonal for x greater than or equal to 0.1. The Mo substitution on the Cu chain site increases the oxygen content above 7, and increases T-c from 81 K for x = 0 to about 86 K for x = 0.05-0.10. The ratio of nominal Mo content to the amount of excess oxygen is very close to 2:3 for all compositions (0.05 less than or equal tox less than or equal to0.2) and may result from the presence of randomly distributed dimers of corner shared MoO6 octahedra. The critical currents for the substituted samples reveal the second peak effect arising from an increased pinning force likely due to the formation of the dimers of MoO6 octahedra in the CuO chains. The irreversibility lines show good pinning characteristics when compared to Y123. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Polish Acad Sci, Inst Low Temp & Struct Res, PL-50950 Wroclaw, Poland. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Rogacki, K (reprint author), No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. NR 20 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 FEB 1 PY 2001 VL 63 IS 5 AR 054501 PG 9 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600096 ER PT J AU Smith, AW Jaeger, HM Rosenbaum, TF Kwok, WK Crabtree, GW AF Smith, AW Jaeger, HM Rosenbaum, TF Kwok, WK Crabtree, GW TI Bose glass melting and the transverse Meissner effect in YBa2Cu3O7-delta single crystals SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; COLUMNAR DEFECTS; UNTWINNED YBA2CU3O7-DELTA; TWIN BOUNDARIES; MATCHING FIELD; VORTEX; TRANSITION; DISORDER; PHASE; LOCALIZATION AB We map out the phase boundary separating the vortex solid and liquid phases in YBa2Cu3O7-delta (YBCO) single crystals with irradiation-induced columnar defects. These randomly distributed, extended defects are expected to localize vortices into a "Bose glass" phase. The transition from the vortex liquid into the Bose glass is predicted to exhibit two fundamental signatures: a vanishing of the linear resistivity and, concomitantly, a screening of de magnetic fields applied perpendicular to the defect axis, the transverse Meissner effect. We have investigated both aspects by systematic measurements on two YBCO single crystals with different defect densities (matching fields of 0.25 and 0.5 T), as well as on an unirradiated control sample. The melting line determined by the temperature, T-m, of vanishing resistance undergoes a 30% decrease in slope as the magnetic field is ramped through the matching field. This is evidence that interstitial vortices are pinned much more weakly than originally thought. If we associate the melting temperature with the Bose glass transition temperature, we obtain static critical exponents of nu (perpendicular to) = 1.7+/-0.2 and nu (perpendicular to) = 1.9+/-0.1 for the crystals with matching fields of 0.25 and 0.5 T, respectively. Simultaneously, we use a ten-element, linear array of microfabricated Hall probe magnetometers to observe directly the flux screening associated with the transverse Meissner state. We find the temperature above which the Meissner state breaks down, T-s, to decrease linearly as the magnetic field applied perpendicular to the columnar defect axis increases. This linear trend, found in both irradiated crystals to cover a range of at least 40 K in T-s, is closely in line with the current theoretical expectation nu (perpendicular to) similar or equal to1. However, already for angles as small as one degree, T-s(H-perpendicular to) falls below T-m(H-perpendicular to) by more than 10 K. Thus, between T-s(H-perpendicular to) and T-m(H-perpendicular to) we observe a large regime characterized by zero resistivity in the absence of a transverse Meissner effect: vortices remain effectively localized even when rotated off the columnar defects. C1 Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. Univ Chicago, Dept Phys, Chicago, IL 60637 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Smith, AW (reprint author), Univ Chicago, James Franck Inst, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 40 TC 8 Z9 8 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 FEB 1 PY 2001 VL 63 IS 6 AR 064514 DI 10.1103/PhysRevB.63.064514 PG 8 WC Physics, Condensed Matter SC Physics GA 401DG UT WOS:000166911400084 ER PT J AU Walko, DA Hong, JI Rao, TVC Wawrzak, Z Seidman, DN Halperin, WP Bedzyk, MJ AF Walko, DA Hong, JI Rao, TVC Wawrzak, Z Seidman, DN Halperin, WP Bedzyk, MJ TI Crystal structure assignment for the heavy-fermion superconductor UPt3 SO PHYSICAL REVIEW B LA English DT Article ID THERMAL-CONDUCTIVITY; GAP STRUCTURE; PHASE; DIFFRACTION; REFINEMENT; ORDER AB Understanding the normal and superconducting states in UPt3 depends critically on its crystal structure. Based on high-energy x-ray diffraction and transmission electron microscopy, we have determined that the crystal structure of UPt3 is trigonal, not hexagonal as traditionally held. Its trigonal structure provides an interpretation of recent high-field muon spin rotation experiments and may be relevant to the existence of the symmetry-breaking field required by most theoretical models of heavy-fermion superconductivity. C1 Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Northwestern Univ, DND CAT, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Walko, DA (reprint author), Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RI HONG, JUNG-IL/B-8566-2008; Seidman, David/B-6697-2009; Bedzyk, Michael/B-7503-2009; Bedzyk, Michael/K-6903-2013 OI HONG, JUNG-IL/0000-0001-7301-6693; NR 31 TC 22 Z9 22 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2001 VL 63 IS 5 AR 054522 DI 10.1103/PhysRevB.63.054522 PG 5 WC Physics, Condensed Matter SC Physics GA 399PB UT WOS:000166820600117 ER PT J AU Barnes, T Black, N Swanson, ES AF Barnes, T Black, N Swanson, ES TI Meson-meson scattering in the quark model: Spin dependence and exotic channels SO PHYSICAL REVIEW C LA English DT Article ID PI-PI-SCATTERING; NUCLEON-NUCLEON-INTERACTION; QUANTUM-FIELD THEORIES; POTENTIAL MODEL; EXCHANGE MODEL; CROSS-SECTIONS; LATTICE QCD; 18 GEV/C; GEV-C; VOLUME DEPENDENCE AB We apply a quark interchange model to spin-dependent and exotic meson-meson scattering. The model includes the complete set of standard quark model forces, including one-gluon exchange spin orbit and tensor and scalar confinement spin orbit. Scattering amplitudes derived assuming simple harmonic oscillator (SHO) and Coulomb plus linear plus hyperfine meson wave functions are compared. In I = 2 pi rr we find approximate agreement with the S-wave phase shift from threshold to 1.5 GeV, where we predict an extremum that is supported by the data. Near threshold we find a rapid energy dependence that may reconcile theoretical estimates of small scattering lengths with experimental indications of larger ones based on extrapolation of measurements at moderate k(pi)(2). In pseudoscalar-vector scattering we find that the quark-quark L . S and T forces map onto L . S and T meson-meson interactions, and the P-wave L . S force is large. Finally we consider scattering in J(PCn), exotic channels, and note that some of the, "Deck effect" mechanisms suggested as possible nonresonant origins of the pi (1)(1400) signal are not viable in this model. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ Bonn, Inst Theoret Kernphys, D-53115 Bonn, Germany. Forschungszentrum Julich, Inst Kernphys, D-52425 Julich, Germany. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. EM barnes@bethe.phy.ornl.gov; nblack@nomad.phys.utk.edu; swansone@pitt.edu NR 81 TC 25 Z9 26 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 025204 DI 10.1103/PhysRevC.63.025204 PG 20 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800066 ER PT J AU Bjoraker, J Venugopalan, R AF Bjoraker, J Venugopalan, R TI From a colored glass condensate to the gluon plasma: Equilibration in high energy heavy ion collisions SO PHYSICAL REVIEW C LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; WILSON RENORMALIZATION-GROUP; WEIZSACKER-WILLIAMS FIELDS; ABELIAN GAUGE-FIELDS; QUARK-GLUON; SMALL-X; TRANSVERSE-MOMENTUM; EFFECTIVE DYNAMICS; MINIJET PRODUCTION; RADIATION AB The initial distribution of gluons at the very early times after a high-energy heavy ion collision is described by the bulk scale Q(s) of gluon saturation in the nuclear wave function. The subsequent evolution of the system towards kinetic equilibrium is described by a nonlinear Landau equation fur the single particle distributions [A. H. Mueller. Nucl. Phys. B572. 227 (2000); Phys. Lett. B 475. 220 (2000)]. In this paper, we solve this equation numerically for the idealized initial conditions proposed by Mueller, and study the evolution of the system to equilibrium. We discuss the sensitivity of our results on the dynamical screening of collinear divergences. In a particular model of dynamical screening, the convergence to the hydrodynamic limit is seen to be rapid relative to hydrodynamic time scales. The equilibration time, the initial temperature, and the chemical potential are shown to have a strong functional dependence on the initial gluon saturation scale Q(s). C1 Univ Minnesota, Dept Phys & Astron, Minneapolis, MN 55455 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Bjoraker, J (reprint author), Univ Minnesota, Dept Phys & Astron, 116 Church St, Minneapolis, MN 55455 USA. NR 64 TC 65 Z9 65 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024609 DI 10.1103/PhysRevC.63.024609 PG 15 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800050 ER PT J AU Dobaczewski, J Magierski, P Nazarewicz, W Satula, W Szymanski, Z AF Dobaczewski, J Magierski, P Nazarewicz, W Satula, W Szymanski, Z TI Odd-even staggering of binding energies as a consequence of pairing and mean-field effects SO PHYSICAL REVIEW C LA English DT Article ID ULTRASMALL METALLIC GRAINS; SINGLE-J SHELL; SUPERCONDUCTING GRAINS; PARTICLE NUMBER; SIMPLE-MODELS; CLUSTERS; NUCLEI; QUADRUPOLE; STATES AB Odd-even staggering of binding energies is studied in finite fermion systems with pairing correlations. We discuss contributions of the pairing and mean field to the staggering, and we construct the binding-energy indicators which measure the magnitude of pairing correlations and the effective single-particle spacings in a given system. The analysis is based on studying several exactly solvable many-body Hamiltonians as well as on the analytical formulas that can be applied in the weak and strong pairing limits. C1 Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. Warsaw Univ Technol, Inst Phys, PL-00662 Warsaw, Poland. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Dobaczewski, J (reprint author), Univ Warsaw, Inst Theoret Phys, Ul Hoza 69, PL-00681 Warsaw, Poland. NR 34 TC 81 Z9 81 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024308 DI 10.1103/PhysRevC.63.024308 PG 12 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800027 ER PT J AU Fahlander, C Palacz, M Rudolph, D Sohler, D Blomqvist, J Kownacki, J Lagergren, K Norlin, LO Nyberg, J Algora, A Andreoiu, C de Angelis, G Atac, A Bazzacco, D Berglund, L Back, T Cederkall, J Cederwall, B Dombradi, Z Fant, B Farnea, E Gadea, A Gorska, M Grawe, H Hashimoto-Saitoh, N Johnson, A Kerek, A Klamra, W Lenzi, SM Likar, A Lipoglavsek, M Moszynski, M Napoli, DR Rossi-Alvarez, C Roth, HA Saitoh, T Seweryniak, D Skeppstedt, O Weiszflog, M Wolinska, M AF Fahlander, C Palacz, M Rudolph, D Sohler, D Blomqvist, J Kownacki, J Lagergren, K Norlin, LO Nyberg, J Algora, A Andreoiu, C de Angelis, G Atac, A Bazzacco, D Berglund, L Back, T Cederkall, J Cederwall, B Dombradi, Z Fant, B Farnea, E Gadea, A Gorska, M Grawe, H Hashimoto-Saitoh, N Johnson, A Kerek, A Klamra, W Lenzi, SM Likar, A Lipoglavsek, M Moszynski, M Napoli, DR Rossi-Alvarez, C Roth, HA Saitoh, T Seweryniak, D Skeppstedt, O Weiszflog, M Wolinska, M TI Excited states in Sn-103: Neutron single-particle energies with respect to Sn-100 SO PHYSICAL REVIEW C LA English DT Article ID HIGH-SPIN STATES; SHELL-MODEL; GE DETECTORS; NUCLEI; POLARIZATION; SPECTRA; TESTS; E2 AB Gamma-ray lines from Sn-103 have been identified for the first time using EUROBALL and ancillary detectors. The level scheme of Sn-103 has been established by means of particle-gated gamma gamma coincidences. The energy spacing between the g(7/2) and d(5/2) neutron single-particle orbitals is determined from the excited states in Sn-103. C1 Lund Univ, Dept Phys, Lund, Sweden. Warsaw Univ, Heavy Ion Lab, Warsaw, Poland. Inst Nucl Res, H-4001 Debrecen, Hungary. Royal Inst Technol, Stockholm, Sweden. Uppsala Univ, Dept Neutron Res, Uppsala, Sweden. Lab Nazl Legnaro, Padua, Italy. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Sez Padova, Padua, Italy. Univ Helsinki, Dept Phys, Helsinki, Finland. Inst Fis Corpuscular, Valencia, Spain. GSI Darmstadt, D-6100 Darmstadt, Germany. Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Jozef Stefan Inst, Ljubljana, Slovenia. Soltan Inst Nucl Studies, Otwock, Poland. Chalmers, S-41296 Gothenburg, Sweden. Argonne Natl Lab, Argonne, IL 60439 USA. RP Lund Univ, Dept Phys, Lund, Sweden. RI Palacz, Marcin/H-3713-2012; Napoli, Daniel R./D-9863-2012; Rudolph, Dirk/D-4259-2009; Dombradi, Zsolt/B-3743-2012; Lenzi, Silvia/I-6750-2012; Cederwall, Bo/M-3337-2014; Gadea, Andres/L-8529-2014; Algora, Alejandro/E-2960-2015 OI Napoli, Daniel R./0000-0002-8154-6958; Rudolph, Dirk/0000-0003-1199-3055; Cederwall, Bo/0000-0003-1771-2656; Gadea, Andres/0000-0002-4233-1970; Algora, Alejandro/0000-0002-5199-1794 NR 25 TC 26 Z9 26 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 021307 DI 10.1103/PhysRevC.63.021307 PG 4 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800008 ER PT J AU Fornal, B Broda, R Daly, PJ Bhattacharyya, P Zhang, CT Grabowski, ZW Ahmad, I Seweryniak, D Wiedenhover, I Carpenter, MP Janssens, RVF Khoo, TL Lauritsen, T Lister, CJ Reiter, P AF Fornal, B Broda, R Daly, PJ Bhattacharyya, P Zhang, CT Grabowski, ZW Ahmad, I Seweryniak, D Wiedenhover, I Carpenter, MP Janssens, RVF Khoo, TL Lauritsen, T Lister, CJ Reiter, P TI Few particle excitations of N=83 isotones Sb-134 and Te-135 from Cm-248 fission SO PHYSICAL REVIEW C LA English DT Article ID PRODUCT GAMMA-RAY; SN-132 REGION AB Gamma-ray cascades in the two- and three-valence-particle nuclei Sb-134 and Te-135 have been studied with Gammasphere using a Cm-248 spontaneous fission source. Isotopic assignments were based in part on coincidences with gamma rays from complementary Rh and Ru fission partners. The Sb-134 and Te-135 level schemes have been considerably extended, with placement of many new high-energy gamma rays; delayed gamma -ray coincidences observed across a 0.51-mus yrast isomer in Te-135 were especially fruitful. The yrast level spectra of both nuclei are interpreted using empirical nucleon-nucleon interactions and compared with the known yrast excitations of their counterparts Bi-210 and Po-211. C1 Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. H Niewodniczanski Inst Nucl Phys, PL-31342 Krakow, Poland. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Royal Inst Technol, Dept Phys, S-10405 Stockholm, Sweden. RP Fornal, B (reprint author), Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 9 TC 36 Z9 37 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024322 DI 10.1103/PhysRevC.63.024322 PG 6 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800041 ER PT J AU Gale, C Jeon, S Kapusta, J AF Gale, C Jeon, S Kapusta, J TI Coherence time effects on J/psi production and suppression in relativistic heavy ion collisions SO PHYSICAL REVIEW C LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; QUARK-GLUON PLASMA; J-PSI-SUPPRESSION; PROTON; DEPENDENCE; PHOTOPRODUCTION; ABSORPTION; SCATTERING; HADRON; GEV/C AB Using a coherence time extracted from high precision proton-nucleus Drell-Yan measurements and a nuclear absorption cross section extracted from pA charmonium production experiments, we study J/psi production and absorption in nucleus-nucleus collisions. We find that coherence time effects are large enough to affect the measured J/psi -to-Drell-Yan ratio. The S+U data at 200A GeV/c measured by NA38 are reproduced quantitatively without the introduction of any new parameters. However, when compared with recent NA50 measurements for Pb+Pb at 158A GeV/c,the data is not reproduced in trend or in magnitude. C1 McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. RP Gale, C (reprint author), McGill Univ, Dept Phys, 3600 Univ St, Montreal, PQ H3A 2T8, Canada. NR 31 TC 1 Z9 1 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024901 PG 4 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800060 ER PT J AU Gao, H Lee, TSH Marinov, V AF Gao, H Lee, TSH Marinov, V TI phi-N bound state SO PHYSICAL REVIEW C LA English DT Article ID QUARKONIUM; SCATTERING AB We show that the QCD van der Waals attractive potential is strong enough to bind a phi meson onto a nucleon inside a nucleus to form a bound state. The direct experimental signature for such an exotic state is proposed in the case of subthreshold phi meson photoproduction from nuclear targets. The production rate is estimated and such an experiment is found to be feasible at the Jefferson Laboratory. C1 MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Gao, H (reprint author), MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. RI Gao, Haiyan/G-2589-2011 NR 10 TC 25 Z9 25 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 022201 DI 10.1103/PhysRevC.63.022201 PG 3 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800011 ER PT J AU Goldhaber, M Shrock, R AF Goldhaber, M Shrock, R TI "Subthreshold" reactions involving nuclear fission SO PHYSICAL REVIEW C LA English DT Article ID MUON NEUTRINO REACTION; C-12 AB We analyze reactions of several types that are naively below threshold but can proceed because of the release of binding energy from nuclear fission and occasionally the formation of Coulombic bound states. These reactions include (i) photofission with pion production and (ii) charged current neutrino-nucleus reactions that lead to fission and/or formation of a Coulomb bound state of a mu (-) with the nucleus of a fission fragment. We comment on the possible experimental observation of these reactions. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Goldhaber, M (reprint author), Brookhaven Natl Lab, Dept Phys, POB 5000, Upton, NY 11973 USA. EM goldhaber@bnl.gov; robert.shrock@sunysb.edu NR 27 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 021303 PG 5 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800004 ER PT J AU Hartley, DJ Reviol, W Riedinger, LL Jin, HQ Smith, BH Yoder, N Zeidan, O Galindo-Uribarri, A Sarantites, DG LaFosse, DR Wilson, JN Mullins, SM AF Hartley, DJ Reviol, W Riedinger, LL Jin, HQ Smith, BH Yoder, N Zeidan, O Galindo-Uribarri, A Sarantites, DG LaFosse, DR Wilson, JN Mullins, SM TI Yrast spectroscopy of Nd-130 and evidence of a highly deformed band SO PHYSICAL REVIEW C LA English DT Article ID MASS REGION; NUCLEI; DEFORMATIONS; SYSTEMATICS AB High-spin states in Nd-130 were populated in the reaction Mo-94(Ca-40,2p2n) at a beam energy of 180 MeV. The ground-state band has been extended to 1(pi) =(32(+)) and three side bands were observed for the first time. In addition, a weak band with a large dynamical moment of inertia was found. The moment of inertia of this sequence is similar to those of structures found to be highly deformed in heavier even-even Nd nuclei. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Australian Natl Univ, Dept Nucl Phys, Canberra, ACT 0200, Australia. RP Hartley, DJ (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. NR 29 TC 9 Z9 9 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024316 PG 8 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800035 ER PT J AU Hecht, MB Roberts, CD Schmidt, SM AF Hecht, MB Roberts, CD Schmidt, SM TI Valence-quark distributions in the pion SO PHYSICAL REVIEW C LA English DT Article ID ELECTROMAGNETIC FORM-FACTORS; DEEP-INELASTIC SCATTERING; DRELL-YAN; PARTON DISTRIBUTIONS; PSEUDOSCALAR MESONS; BETHE-SALPETER; CHARGE-RADIUS; NJL MODEL; SUM-RULES; QCD AB We calculate the pion's valence-quark momentum-fraction probability distribution using a Dyson-Schwinger equation model. Valence quarks with an active mass of 0.30 GeV carry 71% of the pions momentum at a resolving scale q(0) = 0.54 GeV = 1/(0.37 fm). The shape of the calculated distribution is characteristic of a strongly bound system and, evolved from q(0) to q = 2 GeV, it yields first, second, and third moments in agreement with lattice and phenomenological estimates. and valence-quarks carrying 49% of the pion's momentum. However, pointwise there is a discrepancy between our calculated distribution and that hitherto inferred from parametrizations of extant pion-nucleon Drell-Yan data. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Hecht, MB (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 55 TC 83 Z9 84 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 025213 DI 10.1103/PhysRevC.63.025213 PG 8 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800075 ER PT J AU Holden, J Benczer-Koller, N Jakob, G Kumbartzki, C Mertzimekis, TJ Speidel, KH Beausang, CW Krucken, R Macchiavelli, A McMahan, M Phair, L Stuchbery, AE Maier-Komor, P Rogers, W Davies, AD AF Holden, J Benczer-Koller, N Jakob, G Kumbartzki, C Mertzimekis, TJ Speidel, KH Beausang, CW Krucken, R Macchiavelli, A McMahan, M Phair, L Stuchbery, AE Maier-Komor, P Rogers, W Davies, AD TI Single particle degrees of freedom in the transition from deformed to spherical Nd nuclei SO PHYSICAL REVIEW C LA English DT Article ID MAGNETIC-MOMENT MEASUREMENTS; GYROMAGNETIC RATIOS; STATES; DEPENDENCE; ER-166; GD-156; IONS AB The g factors of the 4(1)(+) and 6(1)(+) states in Nd-144,Nd-148, the 4(1)(+) state in Nd-146 and the 6(1)(,)(+) 8(1)(+), and 10(1)(+) states in Nd-150 have been measured for the first time by projectile Coulomb excitation coupled to the transient field technique. The g factors of the 2(1)(+) states of Nd-144,Nd-146,Nd-148,Nd-150 have been remeasured with high precision. The data clearly indicate that, while Nd-148,Nd-150 well described by collective excitations, the structure of the low lying levels in the lighter isotopes is dominated by the 2f(7/2) neutron configuration. C1 Rutgers State Univ, Dept Phys & Astron, New Brunswick, NJ 08903 USA. Univ Bonn, Inst Strahlen & Kernphys, D-53115 Bonn, Germany. Yale Univ, AW Wright Nucl Struct Lab, New Haven, CT 06520 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Australian Natl Univ, Dept Phys Nucl, Canberra, ACT 0200, Australia. Tech Univ Munich, D-85748 Garching, Germany. Westmont Coll, Santa Barbara, CA 93108 USA. RP Holden, J (reprint author), Rutgers State Univ, Dept Phys & Astron, New Brunswick, NJ 08903 USA. RI Mertzimekis, Theo/A-3287-2008; Kruecken, Reiner/A-1640-2013 OI Mertzimekis, Theo/0000-0001-9191-7903; Kruecken, Reiner/0000-0002-2755-8042 NR 42 TC 33 Z9 33 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024315 DI 10.1103/PhysRevC.63.024315 PG 8 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800034 ER PT J AU Horowitz, CJ Pollock, SJ Souder, PA Michaels, R AF Horowitz, CJ Pollock, SJ Souder, PA Michaels, R TI Parity violating measurements of neutron densities SO PHYSICAL REVIEW C LA English DT Article ID ELASTIC ELECTRON-SCATTERING; POLARIZED ELECTRONS; NUCLEAR-STRUCTURE; CHARGE-DENSITY; FORM-FACTORS; FIELD-THEORY; NONCONSERVATION; CESIUM; PB-208; TRANSITION AB Parity violating electron nucleus scattering is a clean and powerful tool for measuring the spatial distributions of neutrons in nuclei with unprecedented accuracy. Parity violation arises from the interference of electromagnetic and weak neutral amplitudes, and the Z(0) of the standard model couples primarily to neutrons at low Q(2). The data can be interpreted with as much confidence as electromagnetic scattering. After briefly reviewing the present theoretical and experimental knowledge of neutron densities, we discuss possible parity violation measurements, their theoretical interpretation, and applications. The experiments are feasible at existing facilities. We show that theoretical corrections are either small or well understood, which makes the interpretation clean. The quantitative relationship to atomic parity nonconservation observables is examined. and we show that the electron scattering asymmetries can be directly applied to atomic parity nonconservation because the observables have approximately the same dependence on nuclear shape. C1 Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Indiana Univ, Ctr Nucl Theory, Bloomington, IN 47405 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Syracuse Univ, Dept Phys, Syracuse, NY 13244 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Horowitz, CJ (reprint author), Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. EM charlie@iucf.indiana.edu; Steven.Pollock@colorado.edu; souder@suhep.phy.syr.edu; rom@jlab.org NR 50 TC 258 Z9 261 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 025501 DI 10.1103/PhysRevC.63.025501 PG 18 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800076 ER PT J AU Kovchegov, YV Levin, E McLerran, L AF Kovchegov, YV Levin, E McLerran, L TI Large scale rapidity correlations in heavy ion collisions SO PHYSICAL REVIEW C LA English DT Article ID WILSON RENORMALIZATION-GROUP; GLUON DISTRIBUTION-FUNCTIONS; NUCLEUS-NUCLEUS COLLISIONS; WEIZSACKER-WILLIAMS FIELD; LOW X PHYSICS; BFKL POMERON; TRANSVERSE-MOMENTUM; INCLUSIVE SPECTRA; DIPOLE PICTURE; HIGH-ENERGIES AB We discuss particle production mechanisms for heavy ion collisions. We present an argument demonstrating how the fluctuations of the number of produced particles in a series of classical emissions can account for Koba-Nielsen-Olesen scaling. We predict rapidity correlations in the particle production in the event-by-event analysis of heavy ion collisions on the rapidity scales of the order of 1/alpha (s). C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. RP Kovchegov, YV (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 56 TC 40 Z9 40 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024903 DI 10.1103/PhysRevC.63.024903 PG 11 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800062 ER PT J AU Maddalena, V Aumann, T Bazin, D Brown, BA Caggiano, JA Davids, B Glasmacher, T Hansen, PG Ibbotson, RW Navin, A Pritychenko, BV Scheit, H Sherrill, BM Steiner, M Tostevin, JA Yurkon, J AF Maddalena, V Aumann, T Bazin, D Brown, BA Caggiano, JA Davids, B Glasmacher, T Hansen, PG Ibbotson, RW Navin, A Pritychenko, BV Scheit, H Sherrill, BM Steiner, M Tostevin, JA Yurkon, J TI Single-neutron knockout reactions: Application to the spectroscopy of C-16,C-17,C-19 SO PHYSICAL REVIEW C LA English DT Article ID REACTION CROSS-SECTIONS; MU-S-ISOMERS; PARALLEL MOMENTUM DISTRIBUTIONS; INTERMEDIATE ENERGY-RANGE; BOUND CARBON ISOTOPES; NUCLEAR SHELL-MODEL; RICH LIGHT ISOTOPES; HALO NUCLEUS; BETA-DECAY; MASS MEASUREMENTS AB The structure of the neutron-rich carbon isotopes C-16,C-17,C-19 has been investigated using one-neutron knockout reactions on a Be-9 target at approximately 60 MeV/nucleon. Partial cross sections and associated momentum distributions corresponding to final states of the C-15,C-16,C-18 residues were measured and compared with predictions based on a shell-model theory and an eikonal model of the reaction mechanism. Spectroscopic factors and l-value assignments are given. The ground-state spins of C-17,C-19 are 3/2(+) and 1/2(+), respectively. It is suggested that the accepted one-neutron separation energy for the ground state of C-19 needs to be revised upwards. C1 Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Univ Surrey, Sch Phys & Chem, Dept Phys, Surrey GU2 7XH, England. Bhabha Atom Res Ctr, Div Nucl Phys, Trombay 400085, Mumbai, India. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Maddalena, V (reprint author), Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. RI Glasmacher, Thomas/C-4462-2008; Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011; Aumann, Thomas/B-1455-2012; Glasmacher, Thomas/H-9673-2014; Scheit, Heiko/B-4779-2008 OI Glasmacher, Thomas/0000-0001-9436-2448; Scheit, Heiko/0000-0002-8937-1101 NR 95 TC 168 Z9 169 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024613 DI 10.1103/PhysRevC.63.024613 PG 17 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800054 ER PT J AU Malov, DE Umar, AS Ernst, DJ Dean, DJ AF Malov, DE Umar, AS Ernst, DJ Dean, DJ TI Relativistic heavy-ion collisions in the dynamical string-parton model SO PHYSICAL REVIEW C LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; PROTON-NUCLEUS; MULTIPARTICLE PRODUCTION; PARTICLE-PRODUCTION; 200-GEV/C PROTON; GAUGE-THEORY; DISTRIBUTIONS; MULTIPLICITY; SCATTERING; ENERGIES AB We develop and extend the dynamical string parton model. This model, which is based on the salient features of QCD, uses classical Nambu-Goto strings with the endpoints identified as partons, an invariant string breaking model of the hadronization process, and interactions described as quark-quark interactions. In this work, the original model is extended to include a phenomenological quantization of the mass of the strings, an analytical technique for treating the incident nucleons as a distribution of string configurations determined by the experimentally measured structure function. the inclusion of the gluonic content of the nucleon through the introduction of purely gluonic strings, and the use of a hard parton-parton interaction taken from perturbative QCD combined with a phenomenological soft interaction. The limited number of parameters in the model are adjusted to e(+)e(-) and p-p data. Utilizing these parameters, the first calculations of the model for p-A and A-A collisions are presented and found to be in reasonable agreement with a broad set of data. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RI Umar, Ahmet/J-4125-2013 OI Umar, Ahmet/0000-0002-9267-5253 NR 52 TC 0 Z9 0 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024902 PG 18 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800061 ER PT J AU Maris, P Roberts, CD Schmidt, SM Tandy, PC AF Maris, P Roberts, CD Schmidt, SM Tandy, PC TI T dependence of pseudoscalar and scaler correlations SO PHYSICAL REVIEW C LA English DT Article ID CHIRAL PHASE-TRANSITION; FINITE-TEMPERATURE; BETHE-SALPETER; PION DECAY; QCD; MASS; MESON; PI(0)->GAMMA-GAMMA; CHROMODYNAMICS; SPECTRUM AB Inhomogeneous pseudoscalar and scalar Bethe-Salpeter equations solved using a renormalization-group-improved rainbow-ladder truncation exhibit bound state poles below and above T-c, the critical temperature for chiral symmetry restoration. Above T-c the bound state amplitudes are identical, as are the positions and residues of the pseudoscalar and scalar poles in the vertices. In the chiral limit the pi (0)-->gamma gamma coupling vanishes at T-c, as do f(pi), m(sigma), and g(sigma pi pi). For light current-quark masses the 2 pi decay channel of the isoscalar-scalar bound state remains open until very near T-c, and the widths of the dominant pion decay modes remain significant in the vicinity of the crossover. C1 Kent State Univ, Dept Phys, Nucl Res Ctr, Kent, OH 44242 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Maris, P (reprint author), Kent State Univ, Dept Phys, Nucl Res Ctr, Kent, OH 44242 USA. NR 55 TC 45 Z9 45 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 025202 DI 10.1103/PhysRevC.63.025202 PG 12 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800064 ER PT J AU Nollett, KM Wiringa, RB Schiavilla, R AF Nollett, KM Wiringa, RB Schiavilla, R TI Six-body calculation of the alpha-deuteron radiative capture cross section SO PHYSICAL REVIEW C LA English DT Article ID MONTE-CARLO CALCULATIONS; ISOTOPIC LITHIUM ABUNDANCES; COSMIC-RAY NUCLEOSYNTHESIS; VARIATIONAL CALCULATIONS; REACTION-RATES; HALO STARS; LI-6; NUCLEI; H-2(ALPHA,GAMMA)LI-6; SCATTERING AB We have computed the cross section for the process d(alpha, gamma)Li-6 at the low energies relevant for primordial nucleosynthesis and comparison with laboratory data. The final state is a six-body wave function generated by the variational Monte Carlo method from the Argonne upsilon (18) and Urbana IX potentials, including improved treatment of large-particle-separation behavior. The initial state is built up from the alpha -particle and deuteron ground-state solutions for these potentials, with phenomenological descriptions of scattering and cluster distortions. The dominant E2 cross section is in reasonable agreement with the laboratory data. Including center-of-energy and other small corrections, we obtain an E1 contribution which is larger than the measured contribution at 2 MeV by a factor of 7. We calculate explicitly the impulse-approximation M1 contribution, which is expected to be very small, and obtain a result consistent with zero. We find little reason to suspect that the cross section is large enough to produce significant Li-6 in the big bang. C1 Univ Chicago, Enrico Fermi Inst, Dept Phys, Chicago, IL 60637 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Jefferson Lab, Newport News, VA 23606 USA. Old Dominion Univ, Dept Phys, Norfolk, VA 23529 USA. RP Univ Chicago, Enrico Fermi Inst, Dept Phys, Chicago, IL 60637 USA. RI Wiringa, Robert/M-4970-2015; OI Nollett, Kenneth/0000-0002-0671-320X NR 39 TC 40 Z9 41 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024003 DI 10.1103/PhysRevC.63.024003 PG 13 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800015 ER PT J AU Oh, Y Titov, AI Lee, TSH AF Oh, Y Titov, AI Lee, TSH TI Nucleon resonances in omega photoproduction SO PHYSICAL REVIEW C LA English DT Article ID RELATIVIZED QUARK-MODEL; VECTOR-MESON PHOTOPRODUCTION; PI-N SCATTERING; POLARIZATION OBSERVABLES; HYPERFINE INTERACTIONS; ELASTIC-SCATTERING; BARYON RESONANCES; CHROMODYNAMICS; ELECTROPRODUCTION; AMPLITUDES AB The role of the nucleon resonances (N*) in omega photoproduction is investigated by using the resonance parameters predicted by Capstick and Roberts [Phys. Rev. D 46, 2864 (1992): 49, 4570 (1994)]. In contrast with the previous investigations based on the SU(6)xO(3) limit of the constituent quark model, the employed N*-->gammaN and N*-->omegaN amplitudes include the configuration mixing effects due to the residual quark-quark interactions. The contributions from the nucleon resonances are found to be significant relative to the nonresonant amplitudes in changing the differential cross sections at large scattering angles and various spin observables. In particular, we suggest that a crucial test of our predictions can be made by measuring the parity asymmetry and beam-target double asymmetry at forward scattering angles. The dominant contributions are found to be from N3/2(divided by)(1910), a missing resonance, and N3/2(-)(1960) which is identified as the D-13(2080) of the Particle Data Group. C1 Acad Sinica, Inst Phys, Taipei 11529, Taiwan. JINR, Bogoliubov Lab Theoret Phys, RU-141980 Dubna, Russia. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Oh, Y (reprint author), Yonsei Univ, Inst Phys & Appl Phys, Seoul 120749, South Korea. EM yoh@phya.yonsei.ac.kr; atitov@thsunl.jinr.ru; lee@anlphy.phy.anl.gov RI Oh, Yongseok/A-2504-2008 OI Oh, Yongseok/0000-0001-9822-8975 NR 51 TC 82 Z9 83 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 025201 DI 10.1103/PhysRevC.63.025201 PG 9 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800063 ER PT J AU Smith, JF Medina-Chico, V Chiara, CJ Fossan, DB Lane, GJ Sears, JM Thorslund, I Amro, H Davids, CN Janssens, RVF Seweryniak, D Hibbert, IM Wadsworth, R Lee, IY Macchiavelli, AO AF Smith, JF Medina-Chico, V Chiara, CJ Fossan, DB Lane, GJ Sears, JM Thorslund, I Amro, H Davids, CN Janssens, RVF Seweryniak, D Hibbert, IM Wadsworth, R Lee, IY Macchiavelli, AO TI Identification of excited states in Cs-117: Systematics of the nu(h(11/12))(2) alignment SO PHYSICAL REVIEW C LA English DT Article ID ROTATIONAL BAND STRUCTURES; COINCIDENCE DATA SETS; CROSSING FREQUENCIES; NEUTRON; SPECTROSCOPY; ISOTOPES; NUCLEI; TERMINATION; ENERGIES; I-115 AB Excited states have been identified in the very neutron-deficient Cs-117(55)62 nucleus. High-spin spectroscopy has been performed using the Gammasphere array, and the assignment of gamma-ray transitions to Cs-117 has been made in a separate experiment in which gamma rays were detected in coincidence with x rays and with recoiling evaporation residues. A previously observed sequence of five gamma rays has been extended by 11 transitions, to high spin, and has been identified as the yrast pi (h(11/2))[550]1/2(-) band of Cs-117. Two additional bands have been observed and are tentatively assigned to be based on protons in the [404]9/2(+) and [422]3/2(+) orbitals. Alignments of pairs of h(11/2) neutrons and protons are observed in all of the bands. The alignments are compared to cranked Woods-Saxon calculations, and are discussed with respect to the effects of a neutron-proton interaction. Of particular interest are the features of the nu (h(11/2))(2) alignment in the pi [550]1/2(-) band and of the pi (h(11/2))(2) alignment in the [422]3/2(+) band. The frequencies of these alignments can be qualitatively explained only if a neutron-proton interaction is taken into account. C1 Univ Manchester, Schuster Lab, Manchester M13 9PL, Lancs, England. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ York, Dept Phys, York YO1 5DD, N Yorkshire, England. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Smith, JF (reprint author), Univ Manchester, Schuster Lab, Manchester M13 9PL, Lancs, England. EM jfs@mags.ph.man.ac.uk RI Lane, Gregory/A-7570-2011 OI Lane, Gregory/0000-0003-2244-182X NR 32 TC 14 Z9 14 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024319 DI 10.1103/PhysRevC.63.024319 PG 11 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800038 ER PT J AU Wang, X Rapaport, J Palarczyk, M Hautala, C Yang, X Prout, DL Van Heerden, I Howes, R Parks, S Sugarbaker, E Brown, BA AF Wang, X Rapaport, J Palarczyk, M Hautala, C Yang, X Prout, DL Van Heerden, I Howes, R Parks, S Sugarbaker, E Brown, BA TI Zero degree polarization transfer measurements for the C-13((p)over-right-arrow,(n)over-right-arrow)N-13 reaction at 197 MeV and empirical Gamow-Teller strength distribution SO PHYSICAL REVIEW C LA English DT Article ID MULTIPOLE DECOMPOSITION; ISOSPIN EXCITATIONS; CROSS-SECTIONS; NUCLEI; SCATTERING; SPIN AB In this paper, we present differential cross sections and complete sets of polarization transfer coefficients, D-ij, obtained in the C-13((p) over right arrow, (n) over right arrow)N-13 reaction studied at zero degree and at 197 MeV incident proton energy. The complete set of polarization observables is used to obtain the Fermi and Gamow-Teller (GT) cross section contributions in the ground state transition, which are then used to deduce GT transition strengths. The sum of the GT strength up to 20 MeV of excitation is compared with shell model calculations. In the region between 20 to 46 MeV of excitation, the differential cross section has been separated in spin and nonspin components. C1 Ohio Univ, Athens, OH 45701 USA. Kent State Univ, Dept Phys, Kent, OH 44242 USA. Indiana Univ, Cyclotron Facil, Bloomington, IN 47405 USA. Ball State Univ, Muncie, IN 47306 USA. Ohio State Univ, Columbus, OH 43210 USA. Michigan State Univ, E Lansing, MI 48824 USA. H Niewodniczanski Inst Nucl Phys, PL-31342 Krakow, Poland. US DOE, Remote Sensing Lab, Las Vegas, NV 89115 USA. Univ Western Cape, ZA-7535 Bellville, South Africa. RP Wang, X (reprint author), Ohio Univ, Athens, OH 45701 USA. NR 45 TC 7 Z9 7 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 024608 DI 10.1103/PhysRevC.63.024608 PG 10 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800049 ER PT J AU Zhang, XQ Hamilton, JH Ramayya, AV Zhu, SJ Hwang, JK Beyer, CJ Kormicki, J Jones, EF Gore, PM Babu, BRS Ginter, TN Aryaeinejad, R Butler-Moore, K Cole, JD Drigert, MW Jewell, JK Reber, EL Gilat, J Lee, IY Rasmussen, JO Daniel, AV Oganessian, YT Ter-Akopian, GM Ma, WC Varmette, PG Bernstein, LA Lougheed, RW Moody, KJ Stoyer, MA Donangelo, R Zhang, JY AF Zhang, XQ Hamilton, JH Ramayya, AV Zhu, SJ Hwang, JK Beyer, CJ Kormicki, J Jones, EF Gore, PM Babu, BRS Ginter, TN Aryaeinejad, R Butler-Moore, K Cole, JD Drigert, MW Jewell, JK Reber, EL Gilat, J Lee, IY Rasmussen, JO Daniel, AV Oganessian, YT Ter-Akopian, GM Ma, WC Varmette, PG Bernstein, LA Lougheed, RW Moody, KJ Stoyer, MA Donangelo, R Zhang, JY TI Observation of a vh(11/2) pair alignment in neutron-rich Pd-118 SO PHYSICAL REVIEW C LA English DT Article ID HIGH-SPIN STATES; PD ISOTOPES; FISSION AB The yrast band was significantly extended to 14(+) and the gamma band to 5(+) in neutron-rich Pd-118 by measuring the gamma-gamma-gamma coincidences emitted from the spontaneous fission of Cf-252 with Gammasphere. The first band crossing was observed in the yrast band in Pd-118 at a frequency of (h) over bar omega approximate to 0.36 MeV at the starting point of the backbending. which is similar to that found in Pd112-116. The first bandbending in the yrast cascade in Pd-118 is interpreted to be built on a two h(11/2) neutron configuration based on its similarity to the yrast bands in even-even Pd112-116. Our result indicates Pd-118 still maintains a prolate shape. The quasineutron Routhian calculations indicate a lower crossing frequency for the h(11/2) level. C1 Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. Tsing Hua Univ, Dept Phys, Beijing 100084, Peoples R China. Joint Inst Heavy Ion Res, Oak Ridge, TN 37835 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Joint Nucl Res Inst, RU-141980 Dubna, Russia. Mississippi State Univ, Dept Phys, Mississippi State, MS 39762 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Fed Rio de Janeiro, BR-68528 Rio De Janeiro, RG, Brazil. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Zhang, XQ (reprint author), Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. NR 13 TC 25 Z9 26 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 027302 DI 10.1103/PhysRevC.63.027302 PG 4 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800081 ER PT J AU Zschiesche, D Papazoglou, P Schramm, S Schaffner-Bielich, J Stocker, H Greiner, W AF Zschiesche, D Papazoglou, P Schramm, S Schaffner-Bielich, J Stocker, H Greiner, W TI Hadrons in dense resonance matter: A chiral SU(3) approach SO PHYSICAL REVIEW C LA English DT Article ID RELATIVISTIC MEAN-FIELD; NUCLEAR-MATTER; FINITE NUCLEI; DELTA-ISOBAR; MODELS; SYSTEMATICS AB A nonlinear chiral SU(3) approach including the spin-3/2 decuplet is developed to describe dense matter. The coupling constants of the baryon resonances to the scalar mesons are determined from the decuplet vacuum masses and SU(3) symmetry relations. Different methods of mass generation show significant differences in the properties of the spin-3/2 particles and in the nuclear equation of state. C1 Inst Theoret Phys, D-60054 Frankfurt, Germany. Brookhaven Natl Lab, Riken BNL Res Ctr, Upton, NY 11973 USA. RP Zschiesche, D (reprint author), Inst Theoret Phys, Postfach 11 19 32, D-60054 Frankfurt, Germany. RI Stoecker, Horst/D-6173-2013 OI Stoecker, Horst/0000-0002-3282-3664 NR 29 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD FEB PY 2001 VL 63 IS 2 AR 025211 DI 10.1103/PhysRevC.63.025211 PG 10 WC Physics, Nuclear SC Physics GA 400JE UT WOS:000166867800073 ER PT J AU Abbott, B Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Balm, PW Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Bassler, U Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Boos, EE Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, B Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Dahl, OI Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelman, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, JT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Grinstein, S Groer, L Grundberg, P Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hou, S Huang, Y Ito, AS Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, VE Landsberg, G Leflat, A Lehner, F Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Maciel, AKA Madaras, RM Manankov, V Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayoroov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Peters, O Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Rha, J Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sculli, J Sen, N Shabalina, E Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Zu, Z Zanabria, M Zheng, H Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Balm, PW Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Bassler, U Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Boos, EE Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, B Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Dahl, OI Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelman, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, JT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Grinstein, S Groer, L Grundberg, P Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hou, S Huang, Y Ito, AS Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, VE Landsberg, G Leflat, A Lehner, F Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Maciel, AKA Madaras, RM Manankov, V Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayoroov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Peters, O Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Rha, J Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sculli, J Sen, N Shabalina, E Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Zu, Z Zanabria, M Zheng, H Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A CA DO Collaboration TI Search for electroweak production of single top quarks in p(p)over-bar collisions SO PHYSICAL REVIEW D LA English DT Article ID W-GLUON FUSION; DETECTOR; COLLIDER; FERMILAB AB We present a search for electroweak production of single top quarks in the electron + jets and muon + jets decay channels. The measurements use approximate to 90 pb(-1) of data from Run 1 of the Fermilab Tevatron collider, collected at 1.8 TeV with the D empty set detector between 1992 and 1995. We use events that include a tagging muon, implying the presence of a b jet. to set an upper limit at the 95% confidence level on the cross section for the s-channel process p (p) over bar --> tb + X of 39 ph. The upper limit for the t-channel process p (p) over bar --> tqb + X is 58 pb. C1 NYU, New York, NY 10003 USA. Univ Rochester, Rochester, NY 14627 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Langston Univ, Langston, OK 73050 USA. Univ Oklahoma, Norman, OK 73019 USA. Brown Univ, Providence, RI 02912 USA. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. Rice Univ, Houston, TX 77005 USA. Univ Washington, Seattle, WA 98195 USA. Columbia Univ, New York, NY 10027 USA. Univ Nebraska, Lincoln, NE 68588 USA. Michigan State Univ, E Lansing, MI 48824 USA. Boston Univ, Boston, MA 02215 USA. Univ Maryland, College Pk, MD 20742 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Kansas State Univ, Manhattan, KS 66506 USA. Univ Kansas, Lawrence, KS 66045 USA. Iowa State Univ, Ames, IA 50011 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Indiana Univ, Bloomington, IN 47405 USA. Northwestern Univ, Evanston, IL 60208 USA. No Illinois Univ, De Kalb, IL 60115 USA. Univ Illinois, Chicago, IL 60607 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Hawaii, Honolulu, HI 96822 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Calif State Univ Fresno, Fresno, CA 93740 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Arizona, Tucson, AZ 85721 USA. Univ Lancaster, Lancaster, England. Inst High Energy Phys, Protvino, Russia. Moscow State Univ, Moscow, Russia. Inst Theoret & Expt Phys, Moscow 117259, Russia. Inst Nucl Phys, Krakow, Poland. Univ Nijmegen, NIKHEF, Nijmegen, Netherlands. CINVESTAV, Mexico City 14000, DF, Mexico. Seoul Natl Univ, Seoul, South Korea. Tata Inst Fundamental Res, Mumbai, India. Univ Delhi, Delhi 110007, India. Panjab Univ, Chandigarh 160014, India. CEA, Serv Phys Particles, DAPNIA, Saclay, France. Univ Paris 06, CNRS, IN2P3, LPNHE, Paris, France. Univ Paris 07, CNRS, IN2P3, LPNHE, Paris, France. Univ Mediterranee, CNRS, IN2P3, CPPM, Marseille, France. Univ Grenoble 1, CNRS, IN2P3, Inst Sci Nucl, Grenoble, France. Univ Buenos Aires, Buenos Aires, DF, Argentina. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. Univ Estado Rio de Janeiro, Rio De Janeiro, Brazil. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Los Andes, Bogota, Colombia. Charles Univ, Prague, Czech Republic. Acad Sci Czech Republ, Inst Phys, Prague, Czech Republic. Univ San Francisco Quito, Quito, Ecuador. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI Shivpuri, R K/A-5848-2010; Chekulaev, Sergey/O-1145-2015; Gutierrez, Phillip/C-1161-2011; Leflat, Alexander/D-7284-2012; Dudko, Lev/D-7127-2012; Boos, Eduard/D-9748-2012; Merkin, Mikhail/D-6809-2012; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; Kim, Sun Kee/G-2042-2015; Yip, Kin/D-6860-2013; Canelli, Florencia/O-9693-2016 OI Dudko, Lev/0000-0002-4462-3192; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; Kim, Sun Kee/0000-0002-0013-0775; Yip, Kin/0000-0002-8576-4311; Canelli, Florencia/0000-0001-6361-2117 NR 19 TC 30 Z9 30 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 FEB 1 PY 2001 VL 63 IS 3 AR 031101 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100001 ER PT J AU Abe, K Abe, K Abe, T Adam, I Akimoto, H Aston, D Baird, KG Baltay, C Band, HR Barklow, TL Bauer, JM Bellodi, G Berger, R Blaylock, G Bogart, JR Bower, GR Brau, JE Breidenbach, M Bugg, WM Burke, D Burnett, TH Burrows, PN Calcaterra, A Cassell, R Chou, A Cohn, HO Coller, JA Convery, MR Cook, V Cowan, RF Crawford, G Damerell, CJS Daoudi, M Dasu, S de Groot, N de Sangro, R Dong, DN Doser, M Dubois, R Erofeeva, I Eschenburg, V Etzion, E Fahey, S Falciai, D Fernandez, JP Flood, K Frey, R Hart, EL Hasuko, K Hertzbach, SS Huffer, ME Huynh, X Iwasaki, M Jackson, DJ Jacques, P Jaros, JA Jiang, ZY Johnson, AS Johnson, JR Kajikawa, R Kalelkar, M Kang, HJ Kofler, RR Kroeger, RS Langston, M Leith, DWG Lia, V Lin, C Mancinelli, G Manly, S Mantovani, G Markiewicz, TW Maruyama, T McKemey, AK Messner, R Moffeit, KC Moore, TB Morii, M Muller, D Murzin, V Narita, S Nauenberg, U Neal, H Nesom, G Oishi, N Onoprienko, D Osborne, LS Panvini, RS Park, CH Peruzzi, I Piccolo, M Piemontese, L Plano, RJ Prepost, R Prescott, CY Ratcliff, BN Reidy, J Reinertsen, PL Rochester, L Rowson, PC Russell, JJ Saxton, OH Schalk, T Schumm, BA Schwiening, J Serbo, VV Shapiro, G Sinev, NB Snyder, JA Staengle, H Stahl, A Stamer, P Steiner, H Su, D Suekane, F Sugiyama, A Suzuki, S Swartz, M Taylor, FE Thom, J Torrence, E Usher, T Va'vra, J Verdier, R Wagner, DL Waite, AP Walston, S Weidemann, AW Weiss, ER Whitaker, JS Williams, SH Willocq, S Wilson, RJ Wisniewski, WJ Wittlin, JL Woods, M Wright, TR Yamamoto, RK Yashima, J Yellin, SJ Young, CC Yuta, H AF Abe, K Abe, K Abe, T Adam, I Akimoto, H Aston, D Baird, KG Baltay, C Band, HR Barklow, TL Bauer, JM Bellodi, G Berger, R Blaylock, G Bogart, JR Bower, GR Brau, JE Breidenbach, M Bugg, WM Burke, D Burnett, TH Burrows, PN Calcaterra, A Cassell, R Chou, A Cohn, HO Coller, JA Convery, MR Cook, V Cowan, RF Crawford, G Damerell, CJS Daoudi, M Dasu, S de Groot, N de Sangro, R Dong, DN Doser, M Dubois, R Erofeeva, I Eschenburg, V Etzion, E Fahey, S Falciai, D Fernandez, JP Flood, K Frey, R Hart, EL Hasuko, K Hertzbach, SS Huffer, ME Huynh, X Iwasaki, M Jackson, DJ Jacques, P Jaros, JA Jiang, ZY Johnson, AS Johnson, JR Kajikawa, R Kalelkar, M Kang, HJ Kofler, RR Kroeger, RS Langston, M Leith, DWG Lia, V Lin, C Mancinelli, G Manly, S Mantovani, G Markiewicz, TW Maruyama, T McKemey, AK Messner, R Moffeit, KC Moore, TB Morii, M Muller, D Murzin, V Narita, S Nauenberg, U Neal, H Nesom, G Oishi, N Onoprienko, D Osborne, LS Panvini, RS Park, CH Peruzzi, I Piccolo, M Piemontese, L Plano, RJ Prepost, R Prescott, CY Ratcliff, BN Reidy, J Reinertsen, PL Rochester, L Rowson, PC Russell, JJ Saxton, OH Schalk, T Schumm, BA Schwiening, J Serbo, VV Shapiro, G Sinev, NB Snyder, JA Staengle, H Stahl, A Stamer, P Steiner, H Su, D Suekane, F Sugiyama, A Suzuki, S Swartz, M Taylor, FE Thom, J Torrence, E Usher, T Va'vra, J Verdier, R Wagner, DL Waite, AP Walston, S Weidemann, AW Weiss, ER Whitaker, JS Williams, SH Willocq, S Wilson, RJ Wisniewski, WJ Wittlin, JL Woods, M Wright, TR Yamamoto, RK Yashima, J Yellin, SJ Young, CC Yuta, H CA SLD Collaboration TI Measurement of A(c) with charmed mesons at the SLAG Large Detector SO PHYSICAL REVIEW D LA English DT Article ID FORWARD-BACKWARD ASYMMETRY; QUARK-ANTIQUARK PRODUCTION; CROSS-SECTION ASYMMETRY; Z(0) RESONANCE; DECAYS; SLD; COLLISIONS; PERFORMANCE; PARAMETERS; A(B) AB We present a direct measurement of the parity-violation parameter A(c) in the coupling of the Z(0) to c quarks with the SLD detector. The measurement is based on a sample of 530 k hadronic Z(0) decays, produced with a mean electron-beam polarization of \P(e)\ = 73%. The tagging of c-quark events is performed using two methods: the exclusive reconstruction of D*(+). D(+), and D(0) mesons, and the soft pions (pi (s)) produced in the decay of D*(+) --> D(0)pi (+)(s). The large background from D mesons produced in B hadron decays is separated efficiently from the signal using precision vertex information. The combination of these two methods yields A(c) = 0.688 +/- 0.041. C1 Aomori Univ, Aomori 030, Japan. Univ Bristol, Bristol, Avon, England. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Boston Univ, Boston, MA 02215 USA. Univ Colorado, Boulder, CO 80309 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Ist Nazl Fis Nucl, Sez Ferrara, I-44100 Ferrara, Italy. Univ Ferrara, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Massachusetts, Amherst, MA 01003 USA. Univ Mississippi, University, MS 38677 USA. MIT, Cambridge, MA 02139 USA. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow 119899, Russia. Nagoya Univ, Chikusa Ku, Nagoya, Aichi 464, Japan. Univ Oregon, Eugene, OR 97403 USA. Univ Oxford, Oxford OX1 3RH, England. Ist Nazl Fis Nucl, Sez Perugia, I-06100 Perugia, Italy. Univ Perugia, I-06100 Perugia, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Rutgers State Univ, Piscataway, NJ 08855 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Soongsil Univ, Seoul 156743, South Korea. Univ Tennessee, Knoxville, TN 37996 USA. Tohoku Univ, Sendai, Miyagi 980, Japan. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Washington, Seattle, WA 98105 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. RP Abe, K (reprint author), Aomori Univ, Aomori 030, Japan. RI de Groot, Nicolo/A-2675-2009; Stahl, Achim/E-8846-2011; de Sangro, Riccardo/J-2901-2012; Frey, Raymond/E-2830-2016; Calcaterra, Alessandro/P-5260-2015 OI Stahl, Achim/0000-0002-8369-7506; de Sangro, Riccardo/0000-0002-3808-5455; Frey, Raymond/0000-0003-0341-2636; Calcaterra, Alessandro/0000-0003-2670-4826 NR 34 TC 4 Z9 4 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 032005 DI 10.1103/PhysRevD.63.032005 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100009 ER PT J AU Adler, S Aoki, M Ardebili, M Atiya, MS Bergbusch, PC Blackmore, EW Bryman, DA Chiang, IH Convery, MR Diwan, MV Frank, JS Haggerty, JS Inagaki, T Ito, MM Kabe, S Kettell, SH Kishi, Y Kitching, P Kobayashi, M Komatsubara, TK Konaka, A Kuno, Y Kuriki, M Kycia, TF Li, KK Littenberg, LS Macdonald, JA McPherson, RA Meyers, PD Mildenberger, J Muramatsu, N Nakano, T Ng, C Numao, T Poutissou, JM Poutissou, R Redlinger, G Sato, T Shinkawa, T Shoemaker, FC Soluk, R Stone, JR Strand, RC Sugimoto, S Witzig, C Yoshimura, Y AF Adler, S Aoki, M Ardebili, M Atiya, MS Bergbusch, PC Blackmore, EW Bryman, DA Chiang, IH Convery, MR Diwan, MV Frank, JS Haggerty, JS Inagaki, T Ito, MM Kabe, S Kettell, SH Kishi, Y Kitching, P Kobayashi, M Komatsubara, TK Konaka, A Kuno, Y Kuriki, M Kycia, TF Li, KK Littenberg, LS Macdonald, JA McPherson, RA Meyers, PD Mildenberger, J Muramatsu, N Nakano, T Ng, C Numao, T Poutissou, JM Poutissou, R Redlinger, G Sato, T Shinkawa, T Shoemaker, FC Soluk, R Stone, JR Strand, RC Sugimoto, S Witzig, C Yoshimura, Y CA E787 Collaboration TI Search for the decay K+->pi(+)pi(0)nu(nu)over-bar SO PHYSICAL REVIEW D LA English DT Article ID ENDCAP PHOTON DETECTOR; 500 MHZ AB The: first search for the decay K+ --> pi (+) pi (0) v(v) over bar has been performed with the E787 detector at BNL. Based on zero events observed in the kinematical search region defined by 90 MeV/c +<188 MeV/c and 135 MeV < E-pi0 < 180 MeV, an upper limit B(K+ pi (+) pi (0) v(v) over bar) < 4.3 x 10(-5) at 90% confidence level is established. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. High Energy Accelerator Res Org, KEK, Tsukuba, Ibaraki 3050801, Japan. Osaka Univ, RCNP, Osaka 5670047, Japan. Princeton Univ, Joseph Henry Labs, Princeton, NJ 08544 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Alberta, Ctr Subatom Res, Edmonton, AB T6G 2N5, Canada. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. RP Adler, S (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 21 TC 11 Z9 11 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 032004 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100008 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azfar, F Azzi-Bachetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Cassada, J 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 Cooper, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Green, C Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Guo, RS Haas, RM Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kilminster, B Kirby, M Kirk, M Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SH Kim, YK Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, M Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Safonov, A Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Taylor, W Tecchio, M Teng, PK Terashi, K Tether, S Theriot, D Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Xu, X Wyss, J Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, Z Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azfar, F Azzi-Bachetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Cassada, J 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 Cooper, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Green, C Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Guo, RS Haas, RM Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kilminster, B Kirby, M Kirk, M Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SH Kim, YK Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, M Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Safonov, A Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Taylor, W Tecchio, M Teng, PK Terashi, K Tether, S Theriot, D Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Xu, X Wyss, J Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, Z Zetti, F Zucchelli, S CA CDF Collaboration TI Measurement of the top quark mass with the collider detector at Fermilab SO PHYSICAL REVIEW D LA English DT Article ID PRODUCTION CROSS-SECTION; SILICON VERTEX DETECTOR; CENTRAL ELECTROMAGNETIC CALORIMETER; LUND MONTE-CARLO; W-BOSON MASS; = 1.8 TEV; P(P)OVER-BAR COLLISIONS; ROOT-S=1.8 TEV; T(T)OVER-BAR PRODUCTION; (P)OVER-BAR-P COLLISIONS AB This report describes a measurement of the top quark mass in p(p) over bar collisions at a center of mass energy of 1.8 TeV. The data sample was collected with the CDF detector during the 1992-1995 collider run at the Fermilab Tevatron, and corresponds to an integrated luminosity of 106 pb(-1). Candidate t(t) over bar events in the "lepton+jets" decay channel provide our most precise measurement of the top quark mass. For each event a top quark mass is determined by using energy and momentum constraints on the production of the t(t) over bar pair and its subsequent decay. A likelihood fit to the distribution of reconstructed masses in the data sample gives a top quark mass in the lepton+jets channel of 176.1 +/- 5.1 (stat) +/- 5.3 (syst) GeV/c(2). Combining this result with measurements from the "all-hadronic" and "dilepton" decay topologies yields a top quark mass of 176.1 +/- 6.6 GeV/c(2). C1 Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, CSIC, Inst Fis Cantabria, E-39005 Santander, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Kyungpook Natl Univ, Korean Hadron Collider Lab, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. High Energy Accelerator Res Org, KEK, Tsukuba, Ibaraki 305, Japan. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Oxford, Oxford OX1 3RH, England. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Affolder, T (reprint author), Acad Sinica, Inst Phys, Taipei 11529, Taiwan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; vilar, rocio/P-8480-2014; Prokoshin, Fedor/E-2795-2012; Introzzi, Gianluca/K-2497-2015; OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Prokoshin, Fedor/0000-0001-6389-5399; Introzzi, Gianluca/0000-0002-1314-2580; Lami, Stefano/0000-0001-9492-0147; CHANG, PAO-TI/0000-0003-4064-388X; Signorelli, Giovanni/0000-0001-8262-8245; Goldstein, Joel/0000-0003-1591-6014 NR 95 TC 60 Z9 60 U1 1 U2 3 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 FEB 1 PY 2001 VL 63 IS 3 AR 032003 DI 10.1103/PhysRevD.63.032003 PG 43 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100007 ER PT J AU Atwood, D Dunietz, I Soni, A AF Atwood, D Dunietz, I Soni, A TI Improved methods for observing CP violation in B-+/--> KD and measuring the CKM phase gamma SO PHYSICAL REVIEW D LA English DT Article ID UNITARITY TRIANGLE; ANGLE-GAMMA; WEAK PHASE; DECAYS; MODES; LIFETIMES; PHYSICS AB Various methods are discussed for obtaining the CKM angle gamma through the interference of the charged B-meson decay channels B--->(K-D0) and B--->K-(D) over bar (0) where the D-0 and (D) over bar (0) decay to common final states. It is found that choosing final states which are not CP eigenstates can lead to large direct CP violation which can give significant bounds on gamma without any theoretical assumptions. If two or more modes are studied, gamma may be extracted with a precision on the order of +/- 15 degrees given similar to 10(8) B-mesons. We also discuss the case of three body decays of the D where additional information may be obtained from the distribution of the D decay products and consider the impact of D (D) over bar oscillations. C1 Iowa State Univ, Dept Phys, Ames, IA 50011 USA. Fermilab, Batavia, IL 60500 USA. Brookhaven Natl Lab, Theory Grp, Upton, NY 11973 USA. RP Atwood, D (reprint author), Iowa State Univ, Dept Phys, Ames, IA 50011 USA. NR 29 TC 206 Z9 208 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 036005 DI 10.1103/PhysRevD.63.036005 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100053 ER PT J AU Bai, JZ Ban, Y Bian, JG Blum, I Chen, AD Chen, GP Chen, HF Chen, HS Chen, J Chen, JC Chen, XD Chen, Y Chen, YB Cheng, BS Choi, JB Cui, XZ Ding, HL Dong, LY Du, ZZ Dunwoodie, W Gao, CS Gao, ML Gao, SQ Gratton, P Gu, JH Gu, SD Gu, WX Guo, YN Guo, ZJ Han, SW Han, Y Harris, FA He, J He, JT He, KL He, M Heng, YK Hitlin, DG Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Huang, GS Huang, XP Huang, YZ Izen, JM Jiang, CH Jin, Y Jones, BD Ju, X Kang, JS Ke, ZJ Kelsey, MH Kim, BK Kim, HJ Kim, SK Kim, TY Kong, D Lai, YF Lang, PF Lankford, A Li, CG Li, D Li, HB Li, J Li, JC Li, PQ Li, W Li, WG Li, XH Li, XN Li, XQ Li, ZC Liu, B Liu, F Liu, HM Liu, J Liu, JP Liu, RG Liu, Y Liu, ZX Lou, XC Lowery, B Lu, GR Lu, F Lu, JG Luo, XL Ma, EC Ma, JM Malchow, R Mao, HS Mao, ZP Meng, XC Mo, XH Nie, J Olsen, SL Oyang, J Paluselli, D Pan, LJ Panetta, J Park, H Porter, F Qi, ND Qi, XR Qian, CD Qiu, JF Qu, YH Que, YK Rong, G Schernau, M Shao, YY Shen, BW Shen, DL Shen, H Shen, HY Shen, XY Shi, F Shi, HZ Song, XF Standifird, J Suh, JY Sun, HS Sun, LF Sun, YZ Tang, SQ Toki, W Tong, GL Varner, GS Wang, F Wang, L Wang, LS Wang, LZ Wang, P Wang, PL Wang, SM Wang, YY Wang, ZY Weaver, M Wei, CL Wu, N Wu, YG Xi, DM Xia, XM Xie, Y Xie, YH Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, HX Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yu, CS Yu, CX Yu, GW Yu, YH Yu, ZQ Yuan, CZ Yuan, Y Zhang, BY Zhang, C Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JW Zhang, L Zhang, L Zhang, LS Zhang, P Zhang, QJ Zhang, SQ Zhang, XY Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, JW Zhao, M Zhao, WR Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhou, BQ Zhou, L Zhu, KJ Zhu, QM Zhu, YC Zhu, YS Zhu, ZA Zhuang, BA AF Bai, JZ Ban, Y Bian, JG Blum, I Chen, AD Chen, GP Chen, HF Chen, HS Chen, J Chen, JC Chen, XD Chen, Y Chen, YB Cheng, BS Choi, JB Cui, XZ Ding, HL Dong, LY Du, ZZ Dunwoodie, W Gao, CS Gao, ML Gao, SQ Gratton, P Gu, JH Gu, SD Gu, WX Guo, YN Guo, ZJ Han, SW Han, Y Harris, FA He, J He, JT He, KL He, M Heng, YK Hitlin, DG Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Huang, GS Huang, XP Huang, YZ Izen, JM Jiang, CH Jin, Y Jones, BD Ju, X Kang, JS Ke, ZJ Kelsey, MH Kim, BK Kim, HJ Kim, SK Kim, TY Kong, D Lai, YF Lang, PF Lankford, A Li, CG Li, D Li, HB Li, J Li, JC Li, PQ Li, W Li, WG Li, XH Li, XN Li, XQ Li, ZC Liu, B Liu, F Liu, HM Liu, J Liu, JP Liu, RG Liu, Y Liu, ZX Lou, XC Lowery, B Lu, GR Lu, F Lu, JG Luo, XL Ma, EC Ma, JM Malchow, R Mao, HS Mao, ZP Meng, XC Mo, XH Nie, J Olsen, SL Oyang, J Paluselli, D Pan, LJ Panetta, J Park, H Porter, F Qi, ND Qi, XR Qian, CD Qiu, JF Qu, YH Que, YK Rong, G Schernau, M Shao, YY Shen, BW Shen, DL Shen, H Shen, HY Shen, XY Shi, F Shi, HZ Song, XF Standifird, J Suh, JY Sun, HS Sun, LF Sun, YZ Tang, SQ Toki, W Tong, GL Varner, GS Wang, F Wang, L Wang, LS Wang, LZ Wang, P Wang, PL Wang, SM Wang, YY Wang, ZY Weaver, M Wei, CL Wu, N Wu, YG Xi, DM Xia, XM Xie, Y Xie, YH Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, HX Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yu, CS Yu, CX Yu, GW Yu, YH Yu, ZQ Yuan, CZ Yuan, Y Zhang, BY Zhang, C Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JW Zhang, L Zhang, L Zhang, LS Zhang, P Zhang, QJ Zhang, SQ Zhang, XY Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, JW Zhao, M Zhao, WR Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhou, BQ Zhou, L Zhu, KJ Zhu, QM Zhu, YC Zhu, YS Zhu, ZA Zhuang, BA CA BES Collaboration TI Measurement of psi(2S) decays to baryon pairs SO PHYSICAL REVIEW D LA English DT Article ID J/PSI; ANNIHILATION AB A sample of 3.95M psi (2S) decays registered in the BES detector are used to study final states containing pairs of octet and decuplet baryons. We report branching fractions for psi (2S)--> p(p) over bar, <(Lambda )over bar>, Sigma (0)<()over bar>(0), Xi (-)<()over bar>(+) Delta (++)<()over bar>(--), Sigma (+)(1385)<()over bar>(-)(1385). Xi (0)(1530)<()over bar>(0)(1530). and Omega (-)<()over bar>(+). These results are compared to expectations based on the SU(3)-flavor symmetry, factorization. and perturbative QCD. C1 Inst High Energy Phys, Beijing 100039, Peoples R China. CALTECH, Pasadena, CA 91125 USA. China Ctr Adv Sci & Technol, Beijing 100087, Peoples R China. Chonbuk Natl Univ, Chonju 561756, South Korea. Colorado State Univ, Ft Collins, CO 80523 USA. Hangzhou Univ, Hangzhou 310028, Peoples R China. Henan Normal Univ, Xinxiang 453002, Peoples R China. Huazhong Normal Univ, Wuhan 430079, Peoples R China. Korea Univ, Seoul 136701, South Korea. Nankai Univ, Tianjin 300071, Peoples R China. Peking Univ, Beijing 100871, Peoples R China. Shandong Univ, Jinan 250100, Peoples R China. Shanghai Jiao Tong Univ, Shanghai 200030, Peoples R China. Seoul Natl Univ, Seoul 151742, South Korea. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Calif Irvine, Irvine, CA 92717 USA. Univ Sci & Technol China, Hefei 230026, Peoples R China. Univ Texas Dallas, Richardson, TX 75083 USA. Wuhan Univ, Wuhan 430072, Peoples R China. RP Bai, JZ (reprint author), Inst High Energy Phys, Beijing 100039, Peoples R China. RI Chen, Yu/E-3788-2012; Kim, Sun Kee/G-2042-2015; dong, liaoyuan/A-5093-2015; OI Kim, Sun Kee/0000-0002-0013-0775; Yuan, Chang-Zheng/0000-0002-1652-6686; dong, liaoyuan/0000-0002-4773-5050; Li, Xiaonan/0000-0003-2857-0219 NR 9 TC 15 Z9 16 U1 1 U2 10 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 FEB 1 PY 2001 VL 63 IS 3 AR 032002 DI 10.1103/PhysRevD.63.032002 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100006 ER PT J AU Barger, V Geer, S Raja, R Whisnant, K AF Barger, V Geer, S Raja, R Whisnant, K TI Short-baseline neutrino oscillations at a neutrino factory SO PHYSICAL REVIEW D LA English DT Article ID CP VIOLATION; SUPER-KAMIOKANDE; T-VIOLATION; 3-NEUTRINO OSCILLATIONS; ATMOSPHERIC NEUTRINOS; LSND EXPERIMENT; MASS-SPECTRUM; MATTER; SCATTERING; PHYSICS AB Within the framework of three-neutrino and four-neutrino scenarios that can describe the results of the LSND experiment, we consider the capabilities of short-baseline neutrino oscillation experiments at a neutrino factory. We find that, when short-baseline (L less than or similar to 100 km) neutrino factory measurements are used together with other accelerator-based oscillation results, the complete three-neutrino parameter space can best be determined by measuring the rate of v(e) --> v(tau) oscillations, and measuring CP violation with either v(e) --> v(mu) or v(mu) --> v(tau) oscillations (including the corresponding antineutrino channels). With measurements of CP violation in both v(e) --> v(mu) and v(mu) --> v(tau) it may be possible to distinguish between the three- and four-neutrino cases. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. NR 83 TC 32 Z9 32 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 FEB 1 PY 2001 VL 63 IS 3 AR 033002 DI 10.1103/PhysRevD.63.033002 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100012 ER PT J AU Chen, S Fast, J Hinson, JW Lee, J Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V Cronin-Hennessy, D Lyon, AL Thorndike, EH Savinov, V Coan, TE Fadeyev, V Gao, YS Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, C Bukin, K Dambasuren, E Karamov, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Wang, JC Wolf, A Wu, J Kopp, S Kostin, M Mahmood, AH Csorna, SE Danko, I McLean, KW Xu, Z Godang, R Bonvicini, G Cinabro, D Dubrovin, M McGee, S Zhou, GJ Lipeles, E Pappas, SP Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Chen, GP Gritsan, A Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Drell, PS Duboscq, JE Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Hsu, L Jones, CD Kandaswamy, J Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Palmer, M Patterson, JR Peterson, D Riley, D Romano, A Thayer, JG Urner, D Valant-Spaight, B Viehhauser, G Warburton, A Avery, P Prescott, C Rubiera, AI Stoeck, H Yelton, J Brandenburg, G Ershov, A Kim, DYJ Wilson, R Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Stepaniak, CJ Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Saleem, M Timm, S Wappler, F Anastassov, A Eckart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Schwarthoff, H Thayer, JB von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A AF Chen, S Fast, J Hinson, JW Lee, J Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V Cronin-Hennessy, D Lyon, AL Thorndike, EH Savinov, V Coan, TE Fadeyev, V Gao, YS Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, C Bukin, K Dambasuren, E Karamov, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Wang, JC Wolf, A Wu, J Kopp, S Kostin, M Mahmood, AH Csorna, SE Danko, I McLean, KW Xu, Z Godang, R Bonvicini, G Cinabro, D Dubrovin, M McGee, S Zhou, GJ Lipeles, E Pappas, SP Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Chen, GP Gritsan, A Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Drell, PS Duboscq, JE Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Hsu, L Jones, CD Kandaswamy, J Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Palmer, M Patterson, JR Peterson, D Riley, D Romano, A Thayer, JG Urner, D Valant-Spaight, B Viehhauser, G Warburton, A Avery, P Prescott, C Rubiera, AI Stoeck, H Yelton, J Brandenburg, G Ershov, A Kim, DYJ Wilson, R Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Stepaniak, CJ Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Saleem, M Timm, S Wappler, F Anastassov, A Eckart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Schwarthoff, H Thayer, JB von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A CA CLEO Collaboration TI Study of chi(c1) and chi(c2) meson production in B meson decays SO PHYSICAL REVIEW D LA English DT Article ID P(P)OVER-BAR COLLISIONS; ROOT-S=1.8 TEV; CHARMONIUM PRODUCTION; QCD ANALYSIS; J/PSI; DETECTOR AB Using a sample of 9.7 X 10(6) B (B) over bar meson pairs collected with the CLEO detector, we study B decays to the chi (c1) and chi (c2) charmonia states, which are reconstructed via their radiative decays to J/psi. We first measure the branching fraction for inclusive chi (c1) production in B decays to be B(B --> chi X-c1) = (4.14 +/- 0.31 +/- 0.40) X 10(-3) where the first uncertainty is statistical and the second one is systematic. We derive the branching fractions for direct chi (c1) and chi (c2) production in B decays by subtracting the known contribution of the decay chain B --> psi (2S)X with psi (2S)--> chi (c1,2)gamma. We obtain B[B --> chi (c1) (direct)X] =(3.83 +/- 0.31 +/- 0.40) X 10(-3). No statistically significant signal for chi (c2) production is observed in either case. Using the Feldman-Cousins approach, we determine the 95% confidence intervals to be [0.2.2.0] X 10(-3) for B(B --> chi X-c2). [0.0,1.7] X 10(-3) for B[B --> chi (c2) (direct)X], and [0.00,0.44] for the ratio Gamma [B --> chi (c2) (direct)X-y]/Gamma [B --> chi (c1) (direct)X-s]. We also measure the branching ratio Gamma [B --> chi (c2) (direct)X-y]/Gamma [B --> chi (c1) (direct)X-s] for different X-s configurations by reconstructing B decays into exclusive final states with J/psi, gamma, a kaon, and up to four pions. For all the X-s configurations, we observe a strong chi (c1) signal yet no statistically significant chi (c2) signal. We discuss how our results compare with theoretical predictions in different models of charmonium production. C1 Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Univ Texas, Austin, TX 78712 USA. Univ Texas Pan Amer, Edinburg, TX 78539 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. MIT, Cambridge, MA 02139 USA. RP Chen, S (reprint author), Purdue Univ, W Lafayette, IN 47907 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014 OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039 NR 22 TC 3 Z9 3 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 FEB 1 PY 2001 VL 63 IS 3 AR 031102 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100002 ER PT J AU Coleman, T Olsson, MG AF Coleman, T Olsson, MG TI Semileptonic form factors: A model-independent approach SO PHYSICAL REVIEW D LA English DT Article ID ISGUR-WISE FUNCTION; QUARK EFFECTIVE THEORY; LATTICE QCD; HEAVY MESONS; B DECAYS; EXTRACTION; BOUNDS; BAR AB We demonstrate that the B -->D-(*()) lv form factors can be accurately predicted given the slope parameter rho (2) of the Isgur-Wise function. Only weak assumptions, consistent with lattice results, on the wave function for the light degrees of freedom are required to establish this result. We observe that the QCD and 1/m(Q) corrections can be systematically represented by an effective Isgur-Wise function of shifted slope. This greatly simplifies the analysis of semileptonic B decay. We also investigate what the available semileptonic data can tell us about lattice QCD and heavy quark effective theory. A rigorous identity relating the form factor slope difference rho (2)(D*) - rho (2)(A1) to a combination of form factor intercepts is found. The identity provides a means of checking theoretically evaluated intercepts with experiment. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. NR 26 TC 7 Z9 7 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 032006 DI 10.1103/PhysRevD.63.032006 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100010 ER PT J AU Fasso, A Poirier, J AF Fasso, A Poirier, J TI Spatial and energy distribution of muons in gamma-induced air showers SO PHYSICAL REVIEW D LA English DT Article ID RAY ASTRONOMY; UNDERGROUND DETECTORS; CROSS-SECTION; TEV; SIMULATION; FLUKA; PHOTOPRODUCTION; CALORIMETER; TELESCOPES; CYGNUS-X-3 AB The FLUKA Monte Carlo program is used to calculate the effects of hadroproduction by primary gamma rays incident upon the Earth's atmosphere: for the results presented in this paper, only primary angles at 0 degrees from zenith are considered. The FLUKA code is believed to be quite accurate in reproducing experimental photon hadroproduction data in the 1 GeV to 10 TeV energy range studied. The charged pions which are so produced can decay to muons with sufficient energy to reach ground level. The number of these muons and their radial and energy distribution are studied for incident gamma ray energies from 1 GeV to 10 TeV. The number of these muons is not negligible; they can, in certain circumstances, be used to study potential sources of gamma rays such as gamma ray bursts. It is found, for example, that a 10 TeV incident primary gamma ray produces, on average, 3.4 muons which reach ground level; the gamma ray energy which produces the maximum number of muons at ground level depends on the spectral index of the primary gamma spectrum, a constant which describes how the primary gamma flux rises with decreasing primary energy. For example, for a differential spectral index of 2.7, there is a broad maximum number of muons coming from approximate to 30 GeV primary gamma ray energy. C1 Stanford Linear Accelerator Ctr, Dept Radiat Phys, Stanford, CA 94309 USA. Univ Notre Dame, Dept Phys, Ctr Astrophys, Notre Dame, IN 46556 USA. RP Stanford Linear Accelerator Ctr, Dept Radiat Phys, Stanford, CA 94309 USA. NR 59 TC 6 Z9 6 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 FEB 1 PY 2001 VL 63 IS 3 AR 036002 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100050 ER PT J AU Jalilian-Marian, J Jeon, S Venugopalan, R AF Jalilian-Marian, J Jeon, S Venugopalan, R TI Wong's equations and the small x effective action in QCD SO PHYSICAL REVIEW D LA English DT Article ID WILSON RENORMALIZATION-GROUP; GLUON DISTRIBUTION-FUNCTIONS; WEIZSACKER-WILLIAMS FIELD; WORLDLINE PATH-INTEGRALS; LARGE NUCLEUS; QUANTUM CHROMODYNAMICS; PARTON SATURATION; FEYNMAN DIAGRAMS; HIGH-DENSITY; PHYSICS AB We propose a new form for the small x effective action in QCD. This form of the effective action is motivated by Wong's equations for classical, colored particles in non-Abelian background fields. We show that the BFKL equation, which sums leading logarithms in x, is efficiently reproduced with this form of the action. We argue that this form of the action may be particularly useful in computing next-to-leading-order results in QCD at small x. C1 Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Jalilian-Marian, J (reprint author), Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. NR 43 TC 25 Z9 25 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 036004 DI 10.1103/PhysRevD.63.036004 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100052 ER PT J AU Puglia, SJ Ramsey-Musolf, MJ Zhu, SL AF Puglia, SJ Ramsey-Musolf, MJ Zhu, SL TI Octet baryon charge radii, chiral symmetry, and decuplet intermediate states SO PHYSICAL REVIEW D LA English DT Article ID PERTURBATION-THEORY ANALYSIS; MAGNETIC-MOMENTS; FORM-FACTORS; SIGMA-TERMS AB We compute the octet baryon charge radii to O(1/Lambda chi M-2(N)) in heavy baryon chiral perturbation theory (HB chi PT). We examine the effect of including the decuplet of spin-3/2 baryons explicitly. We find that it does not improve the level of agreement between the HB chi PT and experimental values for the Sigma (-) charge radius. C1 Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. Thomas Jefferson Natl Accelerator Facil, Theory Grp, Newport News, VA 23606 USA. RP Puglia, SJ (reprint author), Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. NR 22 TC 21 Z9 22 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 034014 DI 10.1103/PhysRevD.63.034014 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100030 ER PT J AU Richichi, SJ Severini, H Skubic, P Undrus, A Chen, S Fast, J Hinson, JW Lee, J Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V Cronin-Hennessy, D Lyon, AL Thorndike, EH Jessop, CP Marsiske, H Perl, ML Savinov, V Zhou, X Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, C Bukin, K Dambasuren, E Karamov, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Wang, JC Wolf, A Wu, J Kopp, S Mahmood, AH Csorna, SE Danko, I McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D McGee, S Perera, LP Zhou, GJ Lipeles, E Pappas, SP Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, ME Prell, S Sharma, V Asner, DM Eppich, A Hill, TS Morrison, RJ Nelson, HN Briere, RA Chen, GP Behrens, BH Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kandaswamy, J Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Urner, D Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Davis, R Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Stepaniak, CJ Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Eckhart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Schwarthoff, H Thayer, JB von Toerne, E Zoeller, MM AF Richichi, SJ Severini, H Skubic, P Undrus, A Chen, S Fast, J Hinson, JW Lee, J Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V Cronin-Hennessy, D Lyon, AL Thorndike, EH Jessop, CP Marsiske, H Perl, ML Savinov, V Zhou, X Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, C Bukin, K Dambasuren, E Karamov, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Wang, JC Wolf, A Wu, J Kopp, S Mahmood, AH Csorna, SE Danko, I McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D McGee, S Perera, LP Zhou, GJ Lipeles, E Pappas, SP Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, ME Prell, S Sharma, V Asner, DM Eppich, A Hill, TS Morrison, RJ Nelson, HN Briere, RA Chen, GP Behrens, BH Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kandaswamy, J Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Urner, D Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Davis, R Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Stepaniak, CJ Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Eckhart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Schwarthoff, H Thayer, JB von Toerne, E Zoeller, MM CA CLEO Collaboration TI Study of B ->psi(2S) K and B ->psi(2S) K*(892) decays SO PHYSICAL REVIEW D LA English DT Article ID FINAL-STATES; B-MESONS; FACTORIZATION; DETECTOR; J/PSI AB Color-suppressed decays of B mesons to final states with psi (2S) mesons have been observed with the CLEO detector. The branching fractions for the decays B+--> psi (2S)K+, B+--> psi (2S)K*(892)(+), B-0--> psi (2S)K-0, and B-0--> psi (2S)K*(892)(0) are measured to be (7.8 +/- 0.7 +/- 0.9) x 10(-4), (9.2 +/- 1.9 +/- 1.2) x 10(-4), (5.0 +/- 1.1 +/- 0.6) x 10(-4), and (7.6 +/- 1.1 +/- 1.0) x 10(-4), respectively, where the first uncertainty is statistical and the second is systematic. The first measurement of the longitudinal polarization fraction is extracted from the angular analysis of the B --> psi (2S)K*(892) candidates: Gamma (L)/Gamma = 0.45 +/- 0.11 +/- 0.04. Our measurements of the decays B-0 --> psi (2s)K-0 and B+--> psi (2S)K*(892)(+) are first observations. C1 Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Univ Texas, Austin, TX 78712 USA. Univ Texas Pan Amer, Edinburg, TX 78539 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. MIT, Cambridge, MA 02139 USA. RP Univ Oklahoma, Norman, OK 73019 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014 OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039 NR 19 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 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 031103 DI 10.1103/PhysRevD.63.031103 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100003 ER PT J AU Zhu, SL Puglia, SJ Holstein, BR Ramsey-Musolf, MJ AF Zhu, SL Puglia, SJ Holstein, BR Ramsey-Musolf, MJ TI Chiral symmetry and the parity-violating NN pi Yukawa coupling SO PHYSICAL REVIEW D LA English DT Article ID BARYON MAGNETIC-MOMENTS; CLOUDY-BAG MODEL; PERTURBATION-THEORY ANALYSIS; FORM-FACTORS; NUCLEON COUPLINGS; OCTET BARYONS; QUARK-MODEL; SCATTERING; LOOPS AB We construct the complete SU(2) parity-violating (PV) pi ,N,Delta. interaction Lagrangian with one derivative, and calculate the chiral corrections to the PV Yukawa NNpi coupling constant h(pi) through O(1/Lambda (3)(chi)) in the leading order of heavy baryon expansion. We discuss the relationship between the renormalized h(pi), the measured value of h(pi), and the corresponding quantity calculated microscopically from the standard model four-quark PV interaction. We observe that the renormalized h(pi) depends strongly on a number of a priori unknown parameters in the PV effective Lagrangian. C1 Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. Thomas Jefferson Natl Accelerator Facil, Theory Grp, Newport News, VA 23606 USA. Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. RP Zhu, SL (reprint author), Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. NR 45 TC 18 Z9 18 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 033006 DI 10.1103/PhysRevD.63.033006 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100016 ER PT J AU Zhu, SL Puglia, S Ramsey-Musolf, MJ AF Zhu, SL Puglia, S Ramsey-Musolf, MJ TI Recoil order chiral corrections to baryon octet axial vector currents SO PHYSICAL REVIEW D LA English DT Article ID PERTURBATION-THEORY; FORM AB We calculate chiral corrections to the octet axial vector currents through O(p(3)) using baryon chiral perturbation theory (BCPT). The relativistic BCPT framework allows one to sum an infinite series of recoil corrections at a given order in the chiral expansion. We also include SU(3)-breaking operators occurring at O(p(2)) not previously considered. We determine the corresponding low-energy constants (LEC's) from hyperon semileptonic decay data using a variety of infrared regularization schemes. When decuplet states are integrated out. the chiral expansion of the axial vector currents does not display the proper convergence behavior, regardless of which scheme is chosen. We also observe that recoil corrections are dominated by the leading 1/m(N) contributions. We explore the implications of our analysis for determinations of the strange quark contribution to the nucleon spin, Delta (s). C1 Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. Thomas Jefferson Natl Accelerator Facil, Theory Grp, Newport News, VA 23606 USA. RP Zhu, SL (reprint author), Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. NR 14 TC 27 Z9 27 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD FEB 1 PY 2001 VL 63 IS 3 AR 034002 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 398HD UT WOS:000166750100018 ER PT J AU Chitanvis, SM AF Chitanvis, SM TI Physics of polymer melts SO PHYSICAL REVIEW E LA English DT Article ID DYNAMICS; LIQUIDS AB We have mapped the physics of polymer melts onto a time-dependent Landau-Ginzburg \psi\(4) field theory using techniques of functional integration. Time in the theory is simply a label fur the location of a given monomer along the extent of a flexible chain. With this model, one can show that the limit of infinitesimal concentration of a polymer melt corresponds to a dynamic critical phenomenon. The transition to the entangled stare is also shown to be a critical point. For larger concentrations, when the role of fluctuations is reduced, a mean-held approximation is justifiably employed to show the existence of tubelike structures reminiscent of Edwards' model. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Chitanvis, SM (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 21 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD FEB PY 2001 VL 63 IS 2 BP art. no. EP 021509 DI 10.1103/PhysRevE.63.021509 PN 1 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 403BH UT WOS:000167022300053 PM 11308500 ER PT J AU Kloster, M Maslov, S Tang, C AF Kloster, M Maslov, S Tang, C TI Exact solution of a stochastic directed sandpile model SO PHYSICAL REVIEW E LA English DT Article ID SELF-ORGANIZED CRITICALITY; SOLVED MODEL; UNIVERSALITY AB We introduce and analytically solve a directed sandpile model with stochastic toppling rules. The model clearly belongs to a different universality class from its counterpart with deterministic toppling rules, previously solved by Dhar and Ramaswamy. The critical exponents are D-parallel to = 7/4, tau = 10/7 in two dimensions and D-parallel to = 3/2, tau = 4/3 in one dimension. The upper critical dimension of the model is three, at which the exponents apart from logarithmic corrections reach their mean-field values D-parallel to=2, tau = 3/2. C1 Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NEC Res Inst, Princeton, NJ 08540 USA. RP Kloster, M (reprint author), Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. RI Maslov, Sergei/C-2397-2009 OI Maslov, Sergei/0000-0002-3701-492X NR 19 TC 31 Z9 32 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD FEB PY 2001 VL 63 IS 2 BP art. no. EP 026111 DI 10.1103/PhysRevE.63.026111 PN 2 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 403BK UT WOS:000167022500020 PM 11308546 ER PT J AU Hoover, WG Hoover, CG Isbister, DJ AF Hoover, WG Hoover, CG Isbister, DJ TI Chaos, ergodic convergence, and fractal instability for a thermostated canonical harmonic oscillator SO PHYSICAL REVIEW E LA English DT Article ID NUMERICAL EXPERIMENTS AB The authors thermostat a qp harmonic oscillator using the two additional control variables zeta and xi to simulate Gibbs' canonical distribution. In contrast to the motion of purely Hamiltonian systems, the thermostated oscillator motion is completely ergodic, covering the full four-dimensional {q, p, zeta, xi} phase space. The local Lyapunov spectrum (instantaneous growth rates of a comoving corotating phase-space hypersphere) exhibits singularities like those found earlier for Hamiltonian chaos, reinforcing the notion that chaos requires kinetic-as opposed to statistical-study, both at and away from equilibrium. The exponent singularities appear to have a fractal character. C1 Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, Dept Mech Engn, Methods Dev Grp, Livermore, CA 94550 USA. RP Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. NR 14 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 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD FEB PY 2001 VL 63 IS 2 AR 026209 DI 10.1103/PhysRevE.63.026209 PN 2 PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 403BK UT WOS:000167022500034 PM 11308560 ER PT J AU Byrd, JM De Santis, S AF Byrd, JM De Santis, S TI Longitudinal injection transients in an electron storage ring SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID BEAM; DYNAMICS AB We present the results of an experimental study of the longitudinal beam dynamics at injection in the advanced light source, an electron storage ring. By measuring the longitudinal bunch distribution following injection using a streak camera, we were able to study several useful and interesting effects as well as improve overall injection efficiency. These include measurement and correction of the phase and energy offsets at injection, measurement of the injected bunch length and energy spread, direct observation of phase space filamentation due to the spread in synchrotron frequencies, and measurement of the effective damping rate of the bunch shape including radiation damping and decoherence. We have also made some initial studies of the decay of an uncaptured beam at injection which may provide a novel means of measuring the radiation loss per turn. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Byrd, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD FEB PY 2001 VL 4 IS 2 AR 024401 DI 10.1103/PhysRevSTAB.4.024401 PG 11 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 433EM UT WOS:000168744800006 ER PT J AU Emma, P Raubenhemier, T AF Emma, P Raubenhemier, T TI Systematic approach to damping ring design SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB A design process is described for damping rings in a linear collider where the competing requirements of small equilibrium emittance and fast damping of the injected phase space are needed. A systematic approach to the determination of the basic ring parameters is described. In addition, qualitative consideration is given to minimizing the system cost. The approximate interdependencies of the various lattice parameters are derived and arguments for the parameter choices are presented. In addition, many useful expressions are derived for a theoretical minimum emittance lattice. The design of the damping rings for the Next Linear Collider design are used as examples throughout. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Emma, P (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 18 TC 16 Z9 16 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD FEB PY 2001 VL 4 IS 2 AR 021001 DI 10.1103/PhysRevSTAB.4.021001 PG 16 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 433EM UT WOS:000168744800001 ER PT J AU Raman, SV AF Raman, SV TI Analysis of the hydrated zone in nuclear waste glass forms by electron microprobe, Raman spectroscopy and diffusion models SO PHYSICS AND CHEMISTRY OF GLASSES LA English DT Article ID SILICATE-GLASSES; BOROSILICATE GLASS; SURFACE; BINARY; WATER AB Metal oxides containing borosilicate glasses were investigated for structure, composition and static leaching. Besides leachate analysis, glasses were analysed by electron microprobe at varying primary electron beam energies to determine compositional trends with sample depth. The glass structure was determined by Raman spectroscopy. Structure, composition, Si-O bridging Raman band intensities and diffusion models were empirically correlated to elucidate elemental mobility. The diffusion of water to varying sample depths is apparent from the optical thickness of the hydrated zone. The compositions of the leached glasses approach the unleached levels towards the interior. Na2O and MgO form the disilicates, metaborates and tetraborates. ZrO2 unbridges the network to a metasilicate type. ZrO2 also couples with MgO and Na2O and deprives additional depolymerisation. Consequently, durability increases in the direction of increasing ZrO2 and bridging/nonbridging components. Durability also increases towards the glass interior from pristine surface and elemental release is in the order. Si, O, Mg, Na, B. Silicon is depleted least and is released within ten microns from the surface. Boron is depleted most and continues to be released from deeper levels. Zirconium and aluminum are leach resistant and enrich near the glass surface. Incommensurable leaching between neutron absorber boron and actinide surrogate zirconium necessitates toughening of pristine surface to safeguard high level waste glasses from nuclear criticality. C1 Bechtel BWXT Idaho LLC, Idaho Natl Engn & Environm Lab, Dept Nucl Engn, Idaho Falls, ID 83415 USA. RP Raman, SV (reprint author), Bechtel BWXT Idaho LLC, Idaho Natl Engn & Environm Lab, Dept Nucl Engn, Idaho Falls, ID 83415 USA. NR 46 TC 6 Z9 6 U1 0 U2 2 PU SOC GLASS TECHNOLOGY PI SHEFFIELD PA THORNTON 20 HALLAM GATE ROAD, SHEFFIELD, S YORKSHIRE, ENGLAND S10 5BT SN 0031-9090 J9 PHYS CHEM GLASSES JI Phys. Chem. Glasses PD FEB PY 2001 VL 42 IS 1 BP 27 EP 41 PG 15 WC Chemistry, Physical; Materials Science, Ceramics SC Chemistry; Materials Science GA 419WU UT WOS:000167972400006 ER PT J AU Telenkov, SA Youn, JI Goodman, DM Welch, AJ Milner, TE AF Telenkov, SA Youn, JI Goodman, DM Welch, AJ Milner, TE TI Non-contact measurement of thermal diffusivity in tissue SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article AB We demonstrate the application of an infrared (IR) imaging technique for non-contact determination of thermal diffusivity in biological materials. The proposed method utilizes pulsed laser excitation to Produce an initial three-dimensional temperature distribution in tissue, and records IR images of subsequent heat diffusion. The theoretical model assumes that the time-dependent temperature increase following pulsed laser exposure is due to independent heat diffusion in longitudinal and lateral directions. A nonlinear least-squares algorithm is used to compute the lateral thermal point spread function from a pair of recorded IR images and to determine the thermal diffusivity of a test specimen. The recorded time-sequence of IR images is used to compute thermal diffusivity as a function of increasing time interval between two IR emission images, Experimental application of the method was demonstrated using tissue phantoms, ex vivo samples of hydrated cartilage and in vivo epidermis. C1 Univ Texas, Biomed Engn Program, Austin, TX 78712 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Telenkov, SA (reprint author), Univ Texas, Biomed Engn Program, Austin, TX 78712 USA. NR 11 TC 30 Z9 30 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD FEB PY 2001 VL 46 IS 2 BP 551 EP 558 DI 10.1088/0031-9155/46/2/320 PG 8 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 403YF UT WOS:000167070200020 PM 11229733 ER PT J AU Barate, R De Bonis, I Decamp, D Ghez, P Goy, C Jezequel, S Lees, JP Martin, F Merle, E Minard, MN Pietrzyk, B Bravo, S Casado, MP Chmeissani, M Crespo, JM Fernandez, E Fernandez-Bosman, M Garrido, L Grauges, E Lopez, J Martinez, M Merino, G Miquel, R Mir, LM Pacheco, A Paneque, D Ruiz, H Colaleo, A Creanza, D De Filippis, N de Palma, M Iaselli, G Maggi, G Maggi, M Nuzzo, S Ranieri, A Raso, G Ruggieri, F Selvaggi, G Silvestris, L Tempesta, P Tricomi, A Zito, C Huang, X Lin, J Ouyang, Q Wang, T Xie, Y Xu, R Xue, S Zhang, J Zhang, L Zhao, W Abbaneo, D Azzurri, P Barklow, T Boix, G Buchmuller, O Cattaneo, M Cerutti, F Clerbaux, B Dissertori, G Drevermann, H Forty, RW Frank, M Gianotti, F Greening, TC Hansen, JB Harvey, J Hutchcroft, DE Janot, P Jost, B Kado, M Lemaitre, V Maley, P Mato, P Minten, A Moutoussi, A Ranjard, F Rolandi, L Schlatter, D Schmitt, M Schneider, O Spagnolo, P Tejessy, W Teubert, F Tournefier, E Valassi, A Ward, JJ Wright, AE Hansen, JD Hansen, JR Hansen, PH Nilsson, BS Waananen, A Daskalakis, G Kyriakis, A Markou, C Simopoulou, E Vayaki, A Blondel, A Brient, JC Machefert, F Rouge, A Swynghedauw, M Tanaka, R Videau, H Focardi, E Parrini, G Zachariadou, K Antonelli, A Antonelli, M Bencivenni, G Bologna, G Bossi, F Campana, P Capon, G Chiarella, V Laurelli, P Mannocchi, G Murtas, F Murtas, GP Passalacqua, L Pepe-Altarelli, M Chalmers, M Halley, AW Kennedy, J Lynch, JG Negus, P O'Shea, V Raeven, B Smith, D Teixeira-Dias, P Thompson, AS Cavanaugh, R Dhamotharan, S Geweniger, C Hanke, P Hepp, V Kluge, EE Leibenguth, G Putzer, A Tittel, K Werner, S Wunsch, M Beuselinck, R Binnie, DM Cameron, W Davies, G Dornan, PJ Girone, M Marinelli, N Nowell, J Przysiezniak, H Sedgbeer, JK Thompson, JC Thomson, E White, R Ghete, VM Girtler, P Kneringer, E Kuhn, D Rudolph, G Bouhova-Thacker, E Bowdery, CK Clarke, DP Ellis, G Finch, AJ Foster, F Hughes, G Jones, RWL Pearson, MR Robertson, NA Smizanska, M Giehl, I Holldorfer, F Jakobs, K Kleinknecht, K Krocker, M Muller, AS Nurnberger, HA Quast, G Renk, B Rohne, E Sander, HG Schmeling, S Wachsmuth, H Zeitnitz, C Ziegler, T Bonissent, A Carr, J Coyle, P Curtil, C Ealet, A Fouchez, D Leroy, O Kachelhoffer, T Payre, P Rousseau, D Tilquin, A Aleppo, M Gilardoni, S Ragusa, F David, A Dietl, H Ganis, G Heister, A Huttmann, K Lutjens, G Mannert, C Manner, W Moser, HG Schael, S Settles, R Stenzel, H Wolf, G Boucrot, J Callot, O Davier, M Duflot, L Grivaz, JF Heusse, P Jacholkowska, A Serin, L Veillet, JJ Videau, I de Regie, JBD Yuan, C Zerwas, D Bagliesi, G Boccali, T Calderini, G Ciulli, V Foa, L Giammanco, A Giassi, A Ligabue, F Messineo, A Palla, F Sanguinetti, G Sciaba, A Sguazzoni, G Tenchini, R Venturi, A Verdini, PG Blair, GA Goles, J Cowan, G Green, MG Jones, LT Medcalf, T Strong, JA Clifft, RW Edgecock, TR Norton, PR Tomalin, IR Bloch-Devaux, B Boumediene, D Colas, P Fabbro, B Lancon, E Lemaire, MC Locci, E Perez, P Rander, J Renardy, JF Rosowsky, A Seager, P Trabelsi, A Tuchming, B Vallage, B Konstantinidis, N Loomis, C Litke, AM Taylor, G Booth, CN Cartwright, S Combley, F Hodgson, PN Lehto, M Thompson, LF Affholderbach, K Bohrer, A Brandt, S Grupen, C Hess, J Misiejuk, A Prange, G Sieler, U Borean, C Giannini, G Gobbo, B He, H Putz, J Rothberg, J Wasserbaech, S Armstrong, SR Cranmer, K Elmer, P Ferguson, DPS Gao, Y Gonzalez, S Hayes, OJ Hu, H Jin, S Kile, J McNamara, PA Nielsen, J Orejudos, W Pan, YB Saadi, Y Scott, IJ von Wimmersperg-Toeller, JH Walsh, J Wiedenmann, W Wu, J Wu, SL Wu, X Zobernig, G AF Barate, R De Bonis, I Decamp, D Ghez, P Goy, C Jezequel, S Lees, JP Martin, F Merle, E Minard, MN Pietrzyk, B Bravo, S Casado, MP Chmeissani, M Crespo, JM Fernandez, E Fernandez-Bosman, M Garrido, L Grauges, E Lopez, J Martinez, M Merino, G Miquel, R Mir, LM Pacheco, A Paneque, D Ruiz, H Colaleo, A Creanza, D De Filippis, N de Palma, M Iaselli, G Maggi, G Maggi, M Nuzzo, S Ranieri, A Raso, G Ruggieri, F Selvaggi, G Silvestris, L Tempesta, P Tricomi, A Zito, C Huang, X Lin, J Ouyang, Q Wang, T Xie, Y Xu, R Xue, S Zhang, J Zhang, L Zhao, W Abbaneo, D Azzurri, P Barklow, T Boix, G Buchmuller, O Cattaneo, M Cerutti, F Clerbaux, B Dissertori, G Drevermann, H Forty, RW Frank, M Gianotti, F Greening, TC Hansen, JB Harvey, J Hutchcroft, DE Janot, P Jost, B Kado, M Lemaitre, V Maley, P Mato, P Minten, A Moutoussi, A Ranjard, F Rolandi, L Schlatter, D Schmitt, M Schneider, O Spagnolo, P Tejessy, W Teubert, F Tournefier, E Valassi, A Ward, JJ Wright, AE Hansen, JD Hansen, JR Hansen, PH Nilsson, BS Waananen, A Daskalakis, G Kyriakis, A Markou, C Simopoulou, E Vayaki, A Blondel, A Brient, JC Machefert, F Rouge, A Swynghedauw, M Tanaka, R Videau, H Focardi, E Parrini, G Zachariadou, K Antonelli, A Antonelli, M Bencivenni, G Bologna, G Bossi, F Campana, P Capon, G Chiarella, V Laurelli, P Mannocchi, G Murtas, F Murtas, GP Passalacqua, L Pepe-Altarelli, M Chalmers, M Halley, AW Kennedy, J Lynch, JG Negus, P O'Shea, V Raeven, B Smith, D Teixeira-Dias, P Thompson, AS Cavanaugh, R Dhamotharan, S Geweniger, C Hanke, P Hepp, V Kluge, EE Leibenguth, G Putzer, A Tittel, K Werner, S Wunsch, M Beuselinck, R Binnie, DM Cameron, W Davies, G Dornan, PJ Girone, M Marinelli, N Nowell, J Przysiezniak, H Sedgbeer, JK Thompson, JC Thomson, E White, R Ghete, VM Girtler, P Kneringer, E Kuhn, D Rudolph, G Bouhova-Thacker, E Bowdery, CK Clarke, DP Ellis, G Finch, AJ Foster, F Hughes, G Jones, RWL Pearson, MR Robertson, NA Smizanska, M Giehl, I Holldorfer, F Jakobs, K Kleinknecht, K Krocker, M Muller, AS Nurnberger, HA Quast, G Renk, B Rohne, E Sander, HG Schmeling, S Wachsmuth, H Zeitnitz, C Ziegler, T Bonissent, A Carr, J Coyle, P Curtil, C Ealet, A Fouchez, D Leroy, O Kachelhoffer, T Payre, P Rousseau, D Tilquin, A Aleppo, M Gilardoni, S Ragusa, F David, A Dietl, H Ganis, G Heister, A Huttmann, K Lutjens, G Mannert, C Manner, W Moser, HG Schael, S Settles, R Stenzel, H Wolf, G Boucrot, J Callot, O Davier, M Duflot, L Grivaz, JF Heusse, P Jacholkowska, A Serin, L Veillet, JJ Videau, I de Regie, JBD Yuan, C Zerwas, D Bagliesi, G Boccali, T Calderini, G Ciulli, V Foa, L Giammanco, A Giassi, A Ligabue, F Messineo, A Palla, F Sanguinetti, G Sciaba, A Sguazzoni, G Tenchini, R Venturi, A Verdini, PG Blair, GA Goles, J Cowan, G Green, MG Jones, LT Medcalf, T Strong, JA Clifft, RW Edgecock, TR Norton, PR Tomalin, IR Bloch-Devaux, B Boumediene, D Colas, P Fabbro, B Lancon, E Lemaire, MC Locci, E Perez, P Rander, J Renardy, JF Rosowsky, A Seager, P Trabelsi, A Tuchming, B Vallage, B Konstantinidis, N Loomis, C Litke, AM Taylor, G Booth, CN Cartwright, S Combley, F Hodgson, PN Lehto, M Thompson, LF Affholderbach, K Bohrer, A Brandt, S Grupen, C Hess, J Misiejuk, A Prange, G Sieler, U Borean, C Giannini, G Gobbo, B He, H Putz, J Rothberg, J Wasserbaech, S Armstrong, SR Cranmer, K Elmer, P Ferguson, DPS Gao, Y Gonzalez, S Hayes, OJ Hu, H Jin, S Kile, J McNamara, PA Nielsen, J Orejudos, W Pan, YB Saadi, Y Scott, IJ von Wimmersperg-Toeller, JH Walsh, J Wiedenmann, W Wu, J Wu, SL Wu, X Zobernig, G CA ALEPH Collaboration TI Search for supersymmetric particles in e(+)e(-) collisions at root s up to 202 GeV and mass limit for the lightest neutralino SO PHYSICS LETTERS B LA English DT Article ID MONTE-CARLO; EVENT GENERATOR; COLLIDERS; PHYSICS; FIELD AB Searches for pair production of squarks, sleptons, charginos and neutralinos are performed with the data collected by the ALEPH detector at LEP at centre-of-mass energies from 188.6 to 201.6 GeV. No evidence for any such signals is observed in a total integrated luminosity of about 410 ph(-1). The negative results of the searches are translated into exclusion domains in the space of the relevant MSSM parameters, which improve significantly on the constraints set previously. Under the assumptions of gaugino and sfermion mass unification, these results allow a 95% C.L. lower limit of 37 GeV/c(2) to be set on the mass of the lightest neutralino for any tan beta and sfermion mass. Additional constraints in the MSSM parameter space are derived from the negative results of ALEPH searches for Higgs bosons. The results are also interpreted in the framework of minimal supergravity. (C) 2001 Published by Elsevier Science B.V. C1 IN2P3, CNRS, Phys Particules Lab, LAPP, F-74019 Annecy Le Vieux, France. Univ Autonoma Barcelona, Inst Fis Altes Energies, E-08193 Barcelona, Spain. Ist Nazl Fis Nucl, Sezione Bari, Dipartimento Fis, I-70126 Bari, Italy. Acad Sinica, Inst High Energy Phys, Beijing, Peoples R China. CERN, European Lab Particle Phys, CH-1211 Geneva 23, Switzerland. Univ Clermont Ferrand, Phys Corpusculaire Lab, IN2P3, CNRS, F-63177 Clermont Ferrand, France. Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Democritos Nucl Res Ctr, NRCD, GR-15310 Attiki, Greece. Ecole Polytech, IN2P3, CNRS, Lab Phys Nucl & Hautes Energies, F-91128 Palaiseau, France. Univ Florence, Dipartimento Fis, Ist Nazl Fis Nucl, Sezione Firenze, I-50125 Florence, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Heidelberg Univ, Kirchoff Inst Phys, D-69120 Heidelberg, Germany. Univ London Imperial Coll Sci Technol & Med, Dept Phys, London SW7 2BZ, England. Univ Innsbruck, Inst Expt Phys, A-6020 Innsbruck, Austria. Univ Lancaster, Dept Phys, Lancaster LA1 4YB, England. Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany. Univ Mediteranee, CNRS, IN2P3, Ctr Phys Particules Marseille, F-13288 Marseille, France. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Ist Nazl Fis Nucl, Sezione Milano, I-20133 Milan, Italy. Max Planck Inst Phys & Astrophys, Werner Heisenberg Inst, D-80805 Munich, Germany. Univ Paris 11, Lab Accelerateur Lineaire, IN2P3, CNRS, F-91898 Orsay, France. Univ Pisa, Dipartimento Fis, Ist Nazl Fis Nucl, Sezione Pisa, I-56010 Pisa, Italy. Scuola Normale Super Pisa, I-56010 Pisa, Italy. Univ London Royal Holloway & Bedford New Coll, Dept Phys, Egham TW20 0EX, Surrey, England. Rutherford Appleton Lab, Particle Phys Dept, Didcot OX11 0QX, Oxon, England. Ctr Etud Saclay, CEA, DAPNIA, Serv Phys Particules, F-91191 Gif Sur Yvette, France. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. Univ Sheffield, Dept Phys, Sheffield S3 7RH, S Yorkshire, England. Univ Siegen, Fachbereich Phys, D-57068 Siegen, Germany. Univ Trieste, Dipartmento Fis, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, Sezione Trieste, I-34127 Trieste, Italy. Univ Washington, Expt Elementary Particule Phys, Seattle, WA 98195 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Barcelona, Barcelona 08208, Spain. CERN, CH-1211 Geneva 23, Switzerland. Univ Palermo, Dipartimento Fis & Tecnol Relat, Palermo, Italy. Dipartimento Fis, I-95129 Catania, Italy. Ist Nazl Fis Nucl, Sezione Catania, I-95129 Catania, Italy. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. CNR, Ist Cosmogeofis, I-10133 Turin, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Tsinghua Univ, Dept Phys, Beijing 100084, Peoples R China. RP IN2P3, CNRS, Phys Particules Lab, LAPP, F-74019 Annecy Le Vieux, France. RI ANTONELLI, ANTONELLA/C-6238-2011; Bosman, Martine/J-9917-2014; Chmeissani, Mokhtar/G-4346-2015; Passalacqua, Luca/F-5127-2011; Focardi, Ettore/E-7376-2012; Venturi, Andrea/J-1877-2012; Valassi, Andrea/K-7506-2012; Rolandi, Luigi (Gigi)/E-8563-2013; Colas, Paul/F-2876-2013; Ruiz, Hugo/H-4141-2013; Jones, Roger/H-5578-2011; O'Shea, Val/G-1279-2010; Fernandez, Enrique/L-5387-2014; Mir, Lluisa-Maria/G-7212-2015; Hansen, John/B-9058-2015; Sguazzoni, Giacomo/J-4620-2015; Murtas, Fabrizio/B-5729-2012; Booth, Christopher/B-5263-2016; Pacheco Pages, Andres/C-5353-2011; Casado, Pilar/H-1484-2015; Ligabue, Franco/F-3432-2014; OI Bosman, Martine/0000-0002-7290-643X; Chmeissani, Mokhtar/0000-0002-2287-4791; Focardi, Ettore/0000-0002-3763-5267; Valassi, Andrea/0000-0001-9322-9565; Rolandi, Luigi (Gigi)/0000-0002-0635-274X; Jones, Roger/0000-0002-6427-3513; O'Shea, Val/0000-0001-7183-1205; Fernandez, Enrique/0000-0002-6405-9488; Mir, Lluisa-Maria/0000-0002-4276-715X; Hansen, John/0000-0002-8422-5543; Sguazzoni, Giacomo/0000-0002-0791-3350; Booth, Christopher/0000-0002-6051-2847; Pacheco Pages, Andres/0000-0001-8210-1734; Casado, Pilar/0000-0002-0394-5646; Boccali, Tommaso/0000-0002-9930-9299; Ligabue, Franco/0000-0002-1549-7107; Bloch-Devaux, Brigitte/0000-0002-2463-1232; Tricomi, Alessia Rita/0000-0002-5071-5501; RASO, Giuseppe/0000-0002-5660-3711; Ciulli, Vitaliano/0000-0003-1947-3396 NR 46 TC 48 Z9 48 U1 0 U2 4 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 FEB 1 PY 2001 VL 499 IS 1-2 BP 67 EP 84 DI 10.1016/S0370-2693(01)00015-6 PG 18 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 401VK UT WOS:000166949100007 ER PT J AU Carena, M Garcia, D Nierste, U Wagner, CEM AF Carena, M Garcia, D Nierste, U Wagner, CEM TI b -> s gamma and supersymmetry with large tan beta SO PHYSICS LETTERS B LA English DT Article ID TOP-QUARK-MASS; ELECTROWEAK SYMMETRY-BREAKING; LEADING QCD CORRECTIONS; GRAND UNIFIED THEORIES; DOUBLET MODEL; B->X-S-GAMMA; UNIFICATION; DECAY AB We discuss the constraints on the supersymmetric parameter space from the decay mode b --> s gamma for large values of tan beta. We improve the theoretical prediction Tol the decay rate by summing very large radiative corrections to all orders in perturbation theory. This extends the validity of the perturbative calculation to the large tan beta regime. This resummation of terms of order alpha (n)(s) tan(n+1) beta is based on a recently proposed effective Lagrangian for the Yukawa interaction of bottom quarks. Moreover, we identify an additional source of tan beta -enhanced terms, which are of order alpha (s) tan beta and involve the charged Higgs boson, and analyse their behaviour in higher orders of perturbation theory. After correcting the current expressions for this rare decay branching ratio at next-to-leading order, we obtain that, contrary to recent claims, the measured branching ratio of b --> s gamma constrains the supersymmetric parameter space in a relevant way, even if tan beta is large. (C) 2001 Published by Elsevier Science B.V. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. CERN, Div Theory, CH-1211 Geneva 23, Switzerland. Argonne Natl Lab, Theoret HEP Div, Argonne, IL 60439 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Santa Cruz, CA 95064 USA. RP Carena, M (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 31 TC 292 Z9 292 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD FEB 1 PY 2001 VL 499 IS 1-2 BP 141 EP 146 DI 10.1016/S0370-2693(01)00009-0 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 401VK UT WOS:000166949100015 ER PT J AU Zhou, Y AF Zhou, Y TI A scaling analysis of turbulent flows driven by Rayleigh-Taylor and Richtmyer-Meshkov instabilities SO PHYSICS OF FLUIDS LA English DT Article ID ISOTROPIC TURBULENCE; NUMERICAL-SIMULATION; KOLMOGOROV-CONSTANT; ENERGY-TRANSFER; INERTIAL RANGE; INTERFACE; UNIVERSALITY; SIMILARITY; NUMBER AB We investigate inertial subrange energy spectra associated with turbulent flows developed by the Rayleigh-Taylor instability and Richtmyer-Meshkov instability (RMI). We argue that the extended Kolmogorov-Kraichnan phenomenology originally developed for turbulent flows with an external agent should also be applicable to these instability driven turbulent flows. A prediction of the mixing zone width for the RMI induced turbulent flow is presented using the RMI modified energy spectrum and a two-equation turbulence model. A possible application to subgrid modeling for large-eddy simulation is discussed briefly. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Zhou, Y (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 40 TC 49 Z9 52 U1 1 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD FEB PY 2001 VL 13 IS 2 BP 538 EP 543 DI 10.1063/1.1336151 PG 6 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 393PC UT WOS:000166478000017 ER PT J AU Sovinec, CR Finn, JM del-Castillo-Negrete, D AF Sovinec, CR Finn, JM del-Castillo-Negrete, D TI Formation and sustainment of electrostatically driven spheromaks in the resistive magnetohydrodynamic model SO PHYSICS OF PLASMAS LA English DT Article ID REVERSED-FIELD PINCH; GUN-INJECTED SPHEROMAK; HELICITY INJECTION; RELAXATION PROCESS; MAGNETIC-FIELD; NUMERICAL-SIMULATION; TILTING INSTABILITY; SPHEX SPHEROMAK; DIFFUSE-PINCH; PLASMA AB The nonlinear time-dependent equations of resistive magnetohydrodynamics are solved in simply connected domains to investigate spheromak formation and sustainment with electrostatic current drive. Spheromak magnetic fields are generated in three-dimensional computations as the nonlinear state resulting from an unstable pinch. Perturbations convert continuously supplied toroidal magnetic flux into poloidal magnetic flux, leading to "flux amplification" of field embedded in the electrodes. Relaxation of the axisymmetric component of the parallel current profile can be substantial, and the final nonlinear state is steady over a wide range of parameters. However, for sufficiently large values of Lundquist number or sufficiently large applied potential, nonsteady final states are observed with periodic relaxation events in some cases. Under most conditions, the saturated configuration exhibits chaotic scattering of the magnetic field lines. Conditions just above the marginal point of pinch instability sustain large closed flux surfaces in steady state; a weakly kinked pinch current threads the toroidal region of closed flux surfaces and imposes stellarator-like helical transform. Closed flux surfaces also form during decay, due to reduced fluctuation levels and average toroidal current driven directly by inductive electric field. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sovinec, CR (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. OI del-Castillo-Negrete, Diego/0000-0001-7183-801X NR 52 TC 59 Z9 59 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD FEB PY 2001 VL 8 IS 2 BP 475 EP 490 DI 10.1063/1.1335585 PG 16 WC Physics, Fluids & Plasmas SC Physics GA 399PD UT WOS:000166820800013 ER PT J AU Levine, JS Coleman, PL Failor, BH Riordan, JC Song, Y Sze, HM Coverdale, CA Deeney, C McGurn, JS Apruzese, JP Davis, J Moosman, B Thornhill, JW Velikovich, AL Weber, BV Bell, D Schneider, R AF Levine, JS Coleman, PL Failor, BH Riordan, JC Song, Y Sze, HM Coverdale, CA Deeney, C McGurn, JS Apruzese, JP Davis, J Moosman, B Thornhill, JW Velikovich, AL Weber, BV Bell, D Schneider, R TI Long-implosion plasma radiation sources using "solid-fill" nozzles SO PHYSICS OF PLASMAS LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; Z-PINCH IMPLOSIONS; K-SHELL RADIATION; EMISSION; ALUMINUM; VELOCITY; ARGON AB Solid-fill nozzles for long-implosion Z-pinch experiments to produce argon K-shell x rays (photon energy >3.1 keV) have been developed. With a 7 cm diam nozzle, which is appropriate for a 200 ns driver, stable implosions at 180 ns and 4 MA have produced peak argon K-shell yields exceeding 15 kJ. As previously seen with short (similar to 100 ns) implosion times, the K-shell yield scales as the fourth power of peak current, I-4. Limited testing with a 10 cm nozzle, which is appropriate for a > 250 ns driver, has also achieved a stable implosion. (C) 2001 American Institute of Physics. C1 Maxwell Phys Int, San Leandro, CA 94577 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. USN, Res Lab, Washington, DC 20375 USA. Def Threat Reduct Agcy, Alexandria, VA 22310 USA. RP Levine, JS (reprint author), Maxwell Phys Int, 2700 Merced St, San Leandro, CA 94577 USA. RI Velikovich, Alexander/B-1113-2009 NR 19 TC 17 Z9 17 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD FEB PY 2001 VL 8 IS 2 BP 533 EP 541 DI 10.1063/1.1333696 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 399PD UT WOS:000166820800018 ER PT J AU Wilks, SC Langdon, AB Cowan, TE Roth, M Singh, M Hatchett, S Key, MH Pennington, D MacKinnon, A Snavely, RA AF Wilks, SC Langdon, AB Cowan, TE Roth, M Singh, M Hatchett, S Key, MH Pennington, D MacKinnon, A Snavely, RA TI Energetic proton generation in ultra-intense laser-solid interactions SO PHYSICS OF PLASMAS LA English DT Article ID HOT-ELECTRONS; ION EMISSION; TARGETS; PLASMAS AB An explanation for the energetic ions observed in the PetaWatt experiments is presented. In solid target experiments with focused intensities exceeding 10(20) W/cm(2), high-energy electron generation, hard bremsstrahlung, and energetic protons have been observed on the backside of the target. In this report, an attempt is made to explain the physical process present that will explain the presence of these energetic protons, as well as explain the number, energy, and angular spread of the protons observed in experiment. In particular, we hypothesize that hot electrons produced on the front of the target are sent through to the back off the target, where they ionize the hydrogen layer there. These ions are then accelerated by the hot electron cloud, to tens of MeV energies in distances of order tens of mum, whereupon they end up being detected in the radiographic and spectrographic detectors. (C) 2001 American Institute of Physics C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wilks, SC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI MacKinnon, Andrew/P-7239-2014; Cowan, Thomas/A-8713-2011 OI MacKinnon, Andrew/0000-0002-4380-2906; Cowan, Thomas/0000-0002-5845-000X NR 16 TC 969 Z9 1015 U1 13 U2 78 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD FEB PY 2001 VL 8 IS 2 BP 542 EP 549 DI 10.1063/1.1333697 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 399PD UT WOS:000166820800019 ER PT J AU Fourkal, E Bychenkov, VY Rozmus, W Sydora, R Kirkby, C Capjack, CE Glenzer, SH Baldis, HA AF Fourkal, E Bychenkov, VY Rozmus, W Sydora, R Kirkby, C Capjack, CE Glenzer, SH Baldis, HA TI Electron distribution function in laser heated plasmas SO PHYSICS OF PLASMAS LA English DT Article ID BINARY COLLISION MODEL; INVERSE BREMSSTRAHLUNG; KINETIC-THEORY; ABSORPTION; SCATTERING; SIMULATION; TRANSPORT; FIELD AB A new electron distribution function has been found in laser heated homogeneous plasmas by an analytical solution to the kinetic equation and by particle simulations. The basic kinetic model describes inverse bremsstrahlung absorption and electron-electron collisions. The non-Maxwellian distribution function is comprised of a super-Gaussian bulk of slow electrons and a Maxwellian tail of energetic particles. The tails are heated due to electron-electron collisions and energy redistribution between superthermal particles and light absorbing slow electrons from the bulk of the distribution function. A practical fit is proposed to the new electron distribution function. Changes to the linear Landau damping of electron plasma waves are discussed. The first evidence for the existence of non-Maxwellian distribution functions has been found in the interpretation, which includes the new distribution function, of the Thomson scattering spectra in gold plasmas [Glenzer , Phys. Rev. Lett. 82, 97 (1999)]. (C) 2001 American Institute of Physics. C1 Univ Alberta, Dept Phys, Inst Theoret Phys, Edmonton, AB T6G 2J1, Canada. Univ Alberta, Dept Elect Engn, Edmonton, AB T6G 2J1, Canada. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. RP Univ Alberta, Dept Phys, Inst Theoret Phys, Edmonton, AB T6G 2J1, Canada. RI Bychenkov, Valery/M-3715-2015 OI Bychenkov, Valery/0000-0001-9624-3813 NR 20 TC 36 Z9 36 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD FEB PY 2001 VL 8 IS 2 BP 550 EP 556 DI 10.1063/1.1334611 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 399PD UT WOS:000166820800020 ER PT J AU Cohen, BI Baldis, HA Berger, RL Estabrook, KG Williams, EA Labaune, C AF Cohen, BI Baldis, HA Berger, RL Estabrook, KG Williams, EA Labaune, C TI Modeling of the competition of stimulated Raman and Brillouin scatter in multiple beam experiments SO PHYSICS OF PLASMAS LA English DT Article ID CROSSED LASER-BEAMS; ION-ACOUSTIC-WAVES; PARAMETRIC-INSTABILITIES; ENERGY-TRANSFER; INHOMOGENEOUS-PLASMA; ELECTROMAGNETIC-WAVES; IRRADIATED PLASMAS; LANGMUIR DECAY; FLOWING PLASMA; POWER TRANSFER AB Multiple laser beam experiments with plastic target foils at the Laboratoire pour L'Utilisation des Lasers Intenses (LULI) facility [Baldis , Phys. Rev. Lett. 77, 2957 (1996)] demonstrated anticorrelation of stimulated Brillouin and Raman backscatter (SBS and SRS). Detailed Thomson scattering diagnostics showed that SBS always precedes SRS, that secondary electron plasma waves sometimes accompanied SRS appropriate to the Langmuir Decay Instability (LDI), and that, with multiple interaction laser beams, the SBS direct backscatter signal in the primary laser beam was reduced while the SRS backscatter signal was enhanced and occurred earlier in time. Analysis and numerical calculations are presented here that evaluate the influences on the competition of SBS and SRS, of local pump depletion in laser hot spots due to SBS, of mode coupling of SBS and LDI ion waves, and of optical mixing of secondary and primary laser beams. These influences can be significant. The calculations take into account simple models of the laser beam hot-spot intensity probability distributions and assess whether ponderomotive and thermal self-focusing are significant. Within the limits of the model, which omits several other potentially important nonlinearities, the calculations suggest the effectiveness of local pump depletion, ion wave mode coupling, and optical mixing in affecting the LULI observations. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. Ecole Polytech, CNRS, Lab Utilisat Lasers Intenses, F-91228 Palaiseau, France. RP Cohen, BI (reprint author), Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. NR 77 TC 8 Z9 8 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD FEB PY 2001 VL 8 IS 2 BP 571 EP 591 DI 10.1063/1.1339234 PG 21 WC Physics, Fluids & Plasmas SC Physics GA 399PD UT WOS:000166820800023 ER PT J AU Hicks, DG Li, CK Seguin, FH Schnittman, JD Ram, AK Frenje, JA Petrasso, RD Soures, JM Meyerhofer, DD Roberts, S Sorce, C Stockl, C Sangster, TC Phillips, TW AF Hicks, DG Li, CK Seguin, FH Schnittman, JD Ram, AK Frenje, JA Petrasso, RD Soures, JM Meyerhofer, DD Roberts, S Sorce, C Stockl, C Sangster, TC Phillips, TW TI Observations of fast protons above 1 MeV produced in direct-drive laser-fusion experiments SO PHYSICS OF PLASMAS LA English DT Article ID ION PRODUCTION; HOT-ELECTRONS; INTENSITY; PLASMAS; EXPLOSION; CLUSTERS; EMISSION; TARGETS AB Fast protons greater than or similar to1 MeV have been observed on the 60-beam, 30 kJ OMEGA laser [T. R. Boehly , Opt. Commun. 133, 495 (1997)] at an intensity I similar or equal to 10(15) W/cm(2) and a wavelength lambda = 0.35 mum. These energies are more than 5 times greater than those observed on previous, single-beam experiments at the same I lambda (2). The total energy in the proton spectrum above 0.2 MeV is similar to0.1% of the laser energy. Some of the proton spectra display intense, regular lines which may be related to ion acoustic perturbations in the expanding plasma. (C) 2001 American Institute of Physics. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. RP Hicks, DG (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Schnittman, Jeremy/D-3168-2012; Hicks, Damien/B-5042-2015 OI Hicks, Damien/0000-0001-8322-9983 NR 22 TC 25 Z9 25 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD FEB PY 2001 VL 8 IS 2 BP 606 EP 610 DI 10.1063/1.1335831 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 399PD UT WOS:000166820800025 ER PT J AU Litvak, AA Fisch, NJ AF Litvak, AA Fisch, NJ TI Resistive instabilities in Hall current plasma discharge SO PHYSICS OF PLASMAS LA English DT Article ID FLOW AB Plasma perturbations in the acceleration channel of a Hall thruster are found to be unstable in the presence of collisions. Both electrostatic lower-hybrid waves and electromagnetic Alfven waves transverse to the applied electric and magnetic field are found to be unstable due to collisions in the ExB electron flow. These results are obtained assuming a two-fluid hydrodynamic model in slab geometry. The characterisitic frequencies of these modes are consistent with experimental observations in Hall current plasma thrusters. (C) 2001 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Litvak, AA (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 9 TC 33 Z9 34 U1 2 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD FEB PY 2001 VL 8 IS 2 BP 648 EP 651 DI 10.1063/1.1336531 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 399PD UT WOS:000166820800032 ER PT J AU Milonni, PW AF Milonni, PW TI Causal discussion of superluminal pulses SO PHYSICS TODAY LA English DT Letter C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Michigan, Ann Arbor, MI 48109 USA. RP Milonni, PW (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 5 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD FEB PY 2001 VL 54 IS 2 BP 14 EP + DI 10.1063/1.1359698 PG 2 WC Physics, Multidisciplinary SC Physics GA 397QN UT WOS:000166707000003 ER PT J AU Courant, ED AF Courant, ED TI John Paul Blewett - Obituary SO PHYSICS TODAY LA English DT Biographical-Item C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Courant, ED (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD FEB PY 2001 VL 54 IS 2 BP 76 EP + DI 10.1063/1.1359718 PG 2 WC Physics, Multidisciplinary SC Physics GA 397QN UT WOS:000166707000017 ER PT J AU Crease, RP AF Crease, RP TI Do physics and politics mix? SO PHYSICS WORLD LA English DT Editorial Material C1 SUNY Stony Brook, Dept Philosophy, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Crease, RP (reprint author), SUNY Stony Brook, Dept Philosophy, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD FEB PY 2001 VL 14 IS 2 BP 17 EP 17 PG 1 WC Physics, Multidisciplinary SC Physics GA 398WT UT WOS:000166780000019 ER PT J AU Gibson, EK McKay, DS Thomas-Keprta, KL Wentworth, SJ Westall, F Steele, A Romanek, CS Bell, MS Toporski, J AF Gibson, EK McKay, DS Thomas-Keprta, KL Wentworth, SJ Westall, F Steele, A Romanek, CS Bell, MS Toporski, J TI Life on Mars: evaluation of the evidence within Martian meteorites ALH84001, Nakhla, and Shergotty SO PRECAMBRIAN RESEARCH LA English DT Review ID POLYCYCLIC AROMATIC-HYDROCARBONS; AUTOPOIETIC SELF-REPRODUCTION; ENDOGENOUS AMINO-ACIDS; ISOTOPIC COMPOSITIONS; LOW-TEMPERATURE; PAST LIFE; PETROLOGIC EVIDENCE; LIQUID WATER; ALLAN-HILLS-84001; ORIGIN AB Analyses both support and are in opposition to the hypothesis that the Martian meteorite ALH84001 contains evidence for possible biogenic activity on Mars. New observations in two additional Martian meteorites, Nakhla (1.3 Ga old) and Shergotty (300-165 Ma old) indicate possible biogenic features. Features in the three Martian meteorites compare favorably with the accepted criteria for terrestrial microfossils and evidence for early life on the Earth. There is strong evidence for the presence of indigenous reduced carbon, biogenic magnetite, and the low-temperature formation of carbonate globules. The morphological similarities between terrestrial microfossils, biofilms, and the features found in the three Martian meteorites are intriguing but have not been conclusively proven. Every investigation must recognize the possibility of terrestrial contamination of the meteorites, whether or not the meteorites are Martian. The search for evidence of ancient life in Martian meteorites has emphasized the difficulties confronting the scientific community with the respect to the positive identification of evidence of past biogenic activity. (C) 2001 Elsevier Science B.V. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Lockheed Martin Corp, Houston, TX 77058 USA. Univ Portsmouth, Portsmouth, Hants, England. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Gibson, EK (reprint author), NASA, Lyndon B Johnson Space Ctr, SN2, Houston, TX 77058 USA. NR 112 TC 48 Z9 50 U1 9 U2 37 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-9268 J9 PRECAMBRIAN RES JI Precambrian Res. PD FEB 1 PY 2001 VL 106 IS 1-2 BP 15 EP 34 DI 10.1016/S0301-9268(00)00122-4 PG 20 WC Geosciences, Multidisciplinary SC Geology GA 402TQ UT WOS:000167004600003 ER PT J AU Simpson, RL AF Simpson, RL TI Untitled SO PROPELLANTS EXPLOSIVES PYROTECHNICS LA English DT Editorial Material C1 Univ Calif Lawrence Livermore Natl Lab, Energet Mat Ctr, Livermore, CA 94550 USA. RP Simpson, RL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Energet Mat Ctr, Livermore, CA 94550 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0721-3115 J9 PROPELL EXPLOS PYROT JI Propellants Explos. Pyrotech. PD FEB PY 2001 VL 26 IS 1 BP 1 EP 1 PG 1 WC Chemistry, Applied; Engineering, Chemical SC Chemistry; Engineering GA 420YR UT WOS:000168033300001 ER PT J AU Souers, PC Anderson, S McGuire, E Murphy, MJ Vitello, P AF Souers, PC Anderson, S McGuire, E Murphy, MJ Vitello, P TI Reactive flow and the size effect SO PROPELLANTS EXPLOSIVES PYROTECHNICS LA English DT Article AB The detonation reaction rate in mus(-1) is derived from Size Effect data using the relation - DUs(partial derivativeU(s)/partial derivativey)(-1), where y = 1/R-o, where U-s is the detonation velocity for a ratestick of radius R-o and D is the infinite-radius detonation velocity. These rates are generally not constant with radius and have pressure exponents ranging from < -5 to >5. JWL++, a simple Reactive Flow code, is run with one rate constant on many samples to compare its rates. JWL++'s pressure exponents vary from about 0.5 to 2.5, and failure occurs outside this range. There are three classes of explosives: (1) those for which the pressure exponent is between 1 and 2 and the rate is nearly constant (e.g. porous urea nitrate): (2) higher pressure explosives with a concave-down shape and large positive pressure exponents (dense TNT); and (3) explosives with negative pressure exponents and concave-up shapes (porous PETN). JWL++ fits only the first class well and has the most trouble with class 3. The pressure exponent in JWL++ is shown to be set by the shape of the Size Effect curve - a condition that arises in order to keep a constant reaction rate for all radii. Some explosives have too much bend to be modeled with one rate constant, e.g. Comp. B near failure. A study with creamed TNT shows that the rate constant need not be changed to account for containment. These results may well be pertinent to a larger consideration of the behavior of Reactive Flow models. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Souers, PC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 20 TC 12 Z9 12 U1 2 U2 3 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0721-3115 J9 PROPELL EXPLOS PYROT JI Propellants Explos. Pyrotech. PD FEB PY 2001 VL 26 IS 1 BP 26 EP 32 PG 7 WC Chemistry, Applied; Engineering, Chemical SC Chemistry; Engineering GA 420YR UT WOS:000168033300006 ER PT J AU Zhou, YF Lau, FW Nauli, S Yang, D Bowie, JU AF Zhou, YF Lau, FW Nauli, S Yang, D Bowie, JU TI Inactivation mechanism of the membrane protein diacylglycerol kinase in detergent solution SO PROTEIN SCIENCE LA English DT Article DE stability; irreversible inactivation; denaturation; aggregation; half life ID IRREVERSIBLE THERMAL-DENATURATION; ESCHERICHIA-COLI; HIGH-TEMPERATURES; STABILITY; ENZYMES AB We have examined the irreversible inactivation mechanism of the membrane protein diacylglycerol kinase in the detergents n-octyl-beta -D-glucopyranoside (OG) at 55 degreesC and n-decyl-maltopyranoside (DM) at 80 degreesC. Under no inactivation conditions did we find any direct evidence for the chemical modifications that are commonly found in soluble proteins. Moreover, protein inactivated at 55 degreesC in OG could be reactivated by an unfolding and refolding protocol, suggesting that the protein is inactivated by a stable conformational change, not a covalent modification. We also found that the inactivation rate decreased with both increasing protein concentration and increasing thermodynamic stability, consistent with an inactivation pathway involving transient dissociation and/or unfolding of the protein. Our results suggest that the primary cause of diacylglycerol kinase inactivation is not low solubility, but poor intrinsic stability in the detergent environment. C1 Univ Calif Los Angeles, Dept Biochem & Chem, Inst Mol Biol, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, US DOE, Inst Mol Biol, Lab Struct Biol & Mol Med, Los Angeles, CA 90095 USA. RP Bowie, JU (reprint author), Univ Calif Los Angeles, Dept Biochem & Chem, Inst Mol Biol, 611 Charles E Young Dr E, Los Angeles, CA 90095 USA. FU NIGMS NIH HHS [R01 GM047485, R01GM59164, R01GM47485] NR 28 TC 33 Z9 33 U1 0 U2 3 PU COLD SPRING HARBOR LAB PRESS PI PLAINVIEW PA 1 BUNGTOWN RD, PLAINVIEW, NY 11724 USA SN 0961-8368 J9 PROTEIN SCI JI Protein Sci. PD FEB PY 2001 VL 10 IS 2 BP 378 EP 383 DI 10.1110/ps.34201 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 418ZZ UT WOS:000167926000015 PM 11266623 ER PT J AU Cave, JW Cho, HS Batchelder, AM Yokota, H Kim, R Wemmer, DE AF Cave, JW Cho, HS Batchelder, AM Yokota, H Kim, R Wemmer, DE TI Solution nuclear magnetic resonance structure of a protein disulfide oxidoreductase from Methanococcus jannaschii SO PROTEIN SCIENCE LA English DT Article DE protein oxidoreductase; NMR structure; thioredoxin homolog; thermophile ID PULSED-FIELD GRADIENTS; BOND FORMATION INVIVO; ESCHERICHIA-COLI; REDOX PROPERTIES; MIXED DISULFIDE; CRYSTAL-STRUCTURE; ACTIVE-SITE; IN-VIVO; THIOREDOXIN; NMR AB The solution structure of the protein disulfide oxidoreductase Mj0307 in the reduced form has been solved by nuclear magnetic resonance. The secondary and tertiary structure of this protein from the archaebacterium Methanococcus jannaschii is similar to the structures that have been solved for the glutaredoxin proteins from Escherichia coli, although Mj0307 also shows features that are characteristic of thioredoxin proteins. Some aspects of Mj0307's unique behavior can be explained by comparing structure-based sequence alignments with mesophilic bacterial and eukaryotic glutaredoxin and thioredoxin proteins. It is proposed that Mj0307, and similar archaebacterial proteins, may be most closely related to the mesophilic bacterial NrdH proteins. Together these proteins may form a unique subgroup within the family of protein disulfide oxidoreductases. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Calvin Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Wemmer, DE (reprint author), Univ Calif Berkeley, Dept Chem, MC-1460, Berkeley, CA 94720 USA. NR 50 TC 10 Z9 10 U1 0 U2 0 PU COLD SPRING HARBOR LAB PRESS PI PLAINVIEW PA 1 BUNGTOWN RD, PLAINVIEW, NY 11724 USA SN 0961-8368 J9 PROTEIN SCI JI Protein Sci. PD FEB PY 2001 VL 10 IS 2 BP 384 EP 396 DI 10.1110/ps.35101 PG 13 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 418ZZ UT WOS:000167926000016 PM 11266624 ER PT J AU Diminnie, JB Liu, XZ Cai, H Wu, ZZ Blanton, JR Chen, TN Tuinman, AA Quisenberry, KT Vallet, CE Zuhr, RA Beach, DB Peng, ZH Wu, YD Concolino, TE Rheingold, AL Xue, ZL AF Diminnie, JB Liu, XZ Cai, H Wu, ZZ Blanton, JR Chen, TN Tuinman, AA Quisenberry, KT Vallet, CE Zuhr, RA Beach, DB Peng, ZH Wu, YD Concolino, TE Rheingold, AL Xue, ZL TI Reactions of d(0) alkylidene and amide complexes with silanes SO PURE AND APPLIED CHEMISTRY LA English DT Article; Proceedings Paper CT XIXth International Conference on Organometallic Chemistry (XIX ICOMC) CY JUL 23-28, 2000 CL SHANGHAL, PEOPLES R CHINA ID ANIONIC PI-LIGANDS; METAL SILYL COMPLEXES; CHEMICAL-VAPOR-DEPOSITION; THIN-FILMS; BIS(ALKYLIDENE); ELIMINATION; ZIRCONIUM; INSERTION; SI; E=C,SI AB Reactions of silanes with d(o) Ta alkylidene and Group 4 amide complexes were found to involve the initial attack on silicon atoms in the silanes by nucleophilic alkylidene carbon or amide nitrogen atoms. The reaction of (Me3SiCH2)(3)Ta(PMe3)[=CHSiMe3] (1) with H2SiR'Ph (R' = Me, Ph) gave (Me3SiCH2)(3)Ta[=C(SiMe3)SiHR'Ph] (2a-b). Similar reactions of these two silanes and (H2PhSi)(2)CH2 with (Me3SiCH2)Ta(PMe3)(2)[=CHR](2) (R = SiMe3, 3; CMe3, 4) yielded novel metallasilacyclobutadienes and a metalladisilacyclohexadiene, respectively. In comparison, the reactions between M(NMe2)(4) (M = Ti, Zr, Hf) and silanes were found to give aminosilanes and metal amide hydride species which were perhaps involved in the formation of titanium-silicon-nitride (Ti-Si-N) ternary materials. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Surface Modificat & Characterizat Res Ctr, Oak Ridge, TN 37831 USA. Hong Kong Univ Sci & Technol, Dept Chem, Hong Kong, Hong Kong, Peoples R China. Univ Delaware, Dept Chem & Biochem, Newark, DE 19716 USA. RP Beach, DB (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Wu, Yun-Dong/G-8463-2013 NR 35 TC 10 Z9 10 U1 0 U2 4 PU INT UNION PURE APPLIED CHEMISTRY PI RES TRIANGLE PK PA 104 TW ALEXANDER DR, PO BOX 13757, RES TRIANGLE PK, NC 27709-3757 USA SN 0033-4545 J9 PURE APPL CHEM JI Pure Appl. Chem. PD FEB PY 2001 VL 73 IS 2 BP 331 EP 335 DI 10.1351/pac200173020331 PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA 432KP UT WOS:000168691000027 ER PT J AU Phillips, WS Hartse, HE Steck, LK AF Phillips, WS Hartse, HE Steck, LK TI Precise relative location of 25-ton chemical explosions at Balapan using IMS stations SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE seismic verification; location; detection; CTBT; IMS ID VELOCITY ANOMALY BENEATH; RIVER TEST SITE; NUCLEAR-EXPLOSIONS; KAZAKHSTAN; PHASES; NETWORK; EVENTS AB We test how well low-magnitude (m(bLg) 1.8 to 2.6), 25-ton chemical explosions at Balapan, Kazakhstan, can be located using IRIS stations and standard earth models, relying on precisely determined relative arrival times of nearly similar, regional and teleseismic waveforms. Three 1997 Balapan explosions were recorded by a number of currently reporting and surrogate IMS stations. Three regional stations and two teleseismic arrays yielded consistent waveforms appropriate For relative picking, Master-event locations based on the AK135 model and ground-truth information from the first, shallowest and best-recorded explosion, fell under 1 km from known locations, for depths constrained to that of the master event. The resulting 90% confidence ellipses covered 12-13 km(2) and contained the true locations; however, results for depth constrained to true depth were slightly less satisfactory. From predictions based on ground truth, we found a P-g-coda phase at Makanchi, Kazakhstan to be misidentified and poorly modeled. After accounting for this, 90% ellipses shrank to 2-3 km(2) and true-depth mislocation vectors became more consistent with confidence-ellipse orientations. These results suggest that a high level of precision could be provided by a tripartite array of calibration shots in cases where models are poorly known. We hope that the successful relocation of these small Balapan shots will support the role of calibration explosions in verification monitoring and special event studies, including on-site inspection. C1 Los Alamos Natl Lab, Seism Res Ctr, Los Alamos, NM 87544 USA. RP Los Alamos Natl Lab, Seism Res Ctr, POB 1663, Los Alamos, NM 87544 USA. EM wsp@lanl.gov; hartse@lanl.gov; lsteck@lanl.gov NR 30 TC 5 Z9 5 U1 0 U2 2 PU SPRINGER BASEL AG PI BASEL PA PICASSOPLATZ 4, BASEL, 4052, SWITZERLAND SN 0033-4553 EI 1420-9136 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD FEB PY 2001 VL 158 IS 1-2 BP 173 EP 192 DI 10.1007/PL00001154 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 430NU UT WOS:000168580900012 ER PT J AU Steck, LK Velasco, AA Cogbill, AH Patton, HJ AF Steck, LK Velasco, AA Cogbill, AH Patton, HJ TI Improving regional seismic event location in China SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE seismic; location; China; kriging; regional ID TRAVEL-TIME TOMOGRAPHY; SOURCE PARAMETERS; TIBETAN PLATEAU; MOMENT TENSOR; CENTRAL-ASIA; TIEN-SHAN; EARTHQUAKES; IDENTIFICATION; VELOCITIES; INVERSION AB In an effort to improve our ability to locate seismic events in China using only regional data, we have developed empirical propagation path corrections and applied such corrections using traditional location routines. Thus far, we have concentrated on corrections to observed P arrival times for crustal events using travel-time observations available from the USGS Earthquake Data Reports, the International Seismic Centre Bulletin, the preliminary International Data Center Reviewed Event Bulletin. and our own travel-time picks from regional data. Location ground truth for events used in this study ranges from 25 km for well-located teleseimic events, down to 2 km for nuclear explosions located using satellite imagery. We also use eight events for which depth is constrained using several waveform methods. We relocate events using the EvLoc algorithm from a region encompassing much of China (latitude 20 degrees -55 degreesN; longitude 65 degrees -115 degreesE). We observe that travel-time residuals exhibit a distance-dependent bias using IASPEI91 as our base model. To remedy this bias, we have developed a new I-D model for China, which removes a significant portion of the distance bias. For individual stations having sufficient P-wave residual data, we produce a map of the regional travel-time residuals from all well-located teleseismic events. Residuals are used only if they are smaller than 10 s in absolute value and if the seismic event is located with accuracy better than 25 km. From the residual data, correction surfaces an constructed using modified Bayesian kriging. Modified Bayesian kriging offers us the advantage of providing well-behaved interpolants and their errors, but requires that we have adequate error estimates associated with the travel-time residuals from which they are constructed. For our P-wave residual error estimate, we use the sum of measurement and modeling errors, where measurement error is based on signal-to-noise ratios when available, and on the published catalog estimate otherwise. Our modeling error originates from the variance of travel-time residuals for our 1-D China model. We calculate propagation path correction surfaces for 74 stations in and around China, including six stations from the International Monitoring system. The statistical significance of each correction surface is evaluated using a cross-validation technique. We show relocation results for nuclear tests from the Balapan and Lap Nor test sites, and for earthquakes located using interferometric synthetic aperture radar. These examples show that the use of propagation path correction surfaces in regional relocations eliminates distance bias in the residual curves and significantly improves the accuracy and precision of seismic event locations. C1 Los Alamos Natl Lab, Los Alamos Seism Res Ctr, Los Alamos, NM 87545 USA. RP Steck, LK (reprint author), Los Alamos Natl Lab, Los Alamos Seism Res Ctr, EES-3 MS D408, Los Alamos, NM 87545 USA. EM lsteck@lanl.gov NR 34 TC 14 Z9 14 U1 1 U2 2 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD FEB PY 2001 VL 158 IS 1-2 BP 211 EP 240 DI 10.1007/PL00001157 PG 30 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 430NU UT WOS:000168580900014 ER PT J AU Claassen, JP AF Claassen, JP TI Robust bearing estimation for three-component stations SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE bearings; estimation; polarization; corrections; location; association ID POLARIZATION ANALYSIS; EVENT DETECTION; 3-COMPONENT; RECORDS AB A robust bearing estimation profess for 3-component stations has been developed and explored. The method, called SEEC for Search, Estimate, Evaluate and Correct, intelligently exploits the inherent information in the arrival at every step of the process to achieve near-optimal results. In particular, the approach uses a consistent framework to define the optimal time-frequency windows on which to make estimates, to make the bearing estimates themselves, to construct metrics helpful in choosing the better estimates or admitting that the bearing is immeasurable, and finally to apply bias corrections when calibration information is available to yield a single final estimate. The algorithm was applied to a small but challenging set of events in a seismically active region. It demonstrated remarkable utility by providing better estimates and insights than previously available. Various monitoring implications are noted from these findings. C1 Sandia Natl Labs, Monitoring Technol Dept, Albuquerque, NM 87185 USA. RP Claassen, JP (reprint author), Sandia Natl Labs, Monitoring Technol Dept, POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 7 Z9 7 U1 0 U2 0 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD FEB PY 2001 VL 158 IS 1-2 BP 349 EP 374 DI 10.1007/PL00001163 PG 26 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 430NU UT WOS:000168580900020 ER PT J AU Harmon, CD Smith, WH Costa, DA AF Harmon, CD Smith, WH Costa, DA TI Criticality calculations for plutonium metal at room temperature in ionic liquid solutions SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article DE ionic liquid; criticality; plutonium AB Critical mass calculations performed on two plutonium metal/ionic liquid mixtures are presented and the results are compared with similar calculations performed on aqueous systems. The ionic liquids considered are the 1-ethyl-3-methyl imidazolium (EMI)/aluminum chloride (AlCl3) and the EMI/tetrafluoroborate (BF4) systems. Our calculations indicate at least an order of magnitude increase in the minimum critical concentration for the ionic liquid-plutonium mixtures over aqueous mixtures. The minimum critical concentrations calculated for Pu/EMIC/AlCl3 and Pu/EMI/BF4 mixtures are 150 and 1000 g/l, respectively. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, Los Alamos, NM 87544 USA. Univ Calif Los Alamos Natl Lab, Nucl Mat Technol Div, Los Alamos, NM 87544 USA. RP Costa, DA (reprint author), Univ Calif Los Alamos Natl Lab, Environm Safety & Hlth Div, POB 1663, Los Alamos, NM 87544 USA. NR 4 TC 43 Z9 47 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD FEB PY 2001 VL 60 IS 3 BP 157 EP 159 DI 10.1016/S0969-806X(00)00336-4 PG 3 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 409MG UT WOS:000167387000002 ER PT J AU Seltzer, SM Inokuti, M Paul, H Bichsel, H AF Seltzer, SM Inokuti, M Paul, H Bichsel, H TI Response to the commentary by J. F. Ziegler (Radiat. res. 152, 219-222, 1999) SO RADIATION RESEARCH LA English DT Letter C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Johannes Kepler Univ Linz, Inst Expt Phys, A-4040 Linz, Austria. Univ Washington, Nucl Phys Lab, Seattle, WA 98195 USA. RP Seltzer, SM (reprint author), Natl Inst Stand & Technol, Mail Stop 8460, Gaithersburg, MD 20899 USA. NR 5 TC 2 Z9 2 U1 1 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD FEB PY 2001 VL 155 IS 2 BP 378 EP 381 PG 4 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 397RF UT WOS:000166708800015 PM 11229330 ER PT J AU Blakely, EA AF Blakely, EA TI Cornelius A. Tobias (1918-2000) - In memoriam SO RADIATION RESEARCH LA English DT Biographical-Item C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Blakely, EA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD FEB PY 2001 VL 155 IS 2 BP 382 EP 385 DI 10.1667/0033-7587(2001)155[0382:CAT]2.0.CO;2 PG 4 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 397RF UT WOS:000166708800016 PM 11175674 ER PT J AU Breitling, F Weigel, RS Downer, MC Tajima, T AF Breitling, F Weigel, RS Downer, MC Tajima, T TI Laser pointing stabilization and control in the submicroradian regime with neural networks SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB The possibility of controling the pointing stability of a slowly pulsed Ti:Sapphire laser system by lowpass filters and artificial neural networks (NN) is investigated by performing time series analysis and computer simulations on experimentally measured datasets. The simulations show that at pulse repetition rates of 20 Hz it is possible to use a feedforward algorithm to reduce the angular standard deviation from 0.7 to 0.3 mu rad. The properties and advantages of NN methods such as automatic adaptation characteristics of a time series are discussed. (C) 2001 American Institute of Physics. C1 Univ Texas, Dept Phys, Austin, TX 78712 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Breitling, F (reprint author), Univ Texas, Dept Phys, Austin, TX 78712 USA. RI Breitling, Frank/I-1543-2013 NR 21 TC 4 Z9 5 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD FEB PY 2001 VL 72 IS 2 BP 1339 EP 1342 DI 10.1063/1.1334624 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 397JA UT WOS:000166688500014 ER PT J AU Zolfaghari, AM Woskov, PP Luckhardt, S Kaita, R AF Zolfaghari, AM Woskov, PP Luckhardt, S Kaita, R TI Characterization of internal MHD modes in Princeton beta experiment modification by ECE fluctuation radiometry SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT Workshop on Advances in Laser Heated Diamond Cell Techniques CY MAY 25-27, 2000 CL ARGONNE NATL LAB, CHICAGO, ILLINOIS SP Natl Sci Fdn, Ctr High Pressure Res, GeoSoilEnviroCars HO ARGONNE NATL LAB ID ELECTRON-CYCLOTRON EMISSION AB Localized measurements of internal magnetohydrodynamic (MHD) activity in the Princeton Beta Experiment-Modification (PBX-M) have been made using a heterodyne radiometer. The radiometer measures third harmonic optically gray electron cyclotron emission (ECE) from the center to the outer edge of the plasma on eight radially localized frequency channels from 112-128 GHz. The radiometer uses a focusing Gaussian optics system, which provides a vertical resolution of approximately 6 cm throughout the plasma. The radial resolution of the diagnostics is limited by the relativistic broadening to approximately 2-3 cm. Long wavelength (k <0.5 cm(-1)) temperature and density fluctuations can therefore be detected using this diagnostic. A MHD mode's characteristics such as pressure fluctuations and mode amplitude can be derived from the coherent fluctuations it causes in the ECE signal using an analytical theory developed by Luckhardt (MIT Plasma Fusion Center Report No. PFC-JA/91-16, 1991). Using this analysis, pressure fluctuations (deltaP/P) have been calculated for high n-number MHD modes in high-beta (p) PBX-M plasmas. (C) 2001 American Institute of Physics. C1 MIT, Cambridge, MA 02139 USA. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08544 USA. RP Zolfaghari, AM (reprint author), Schneider Elect N Amer, Palatine, IL 60067 USA. NR 7 TC 1 Z9 1 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD FEB PY 2001 VL 72 IS 2 BP 1395 EP 1399 DI 10.1063/1.1309007 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 397JA UT WOS:000166688500025 ER PT J AU Phelps, TJ Peters, DJ Marshall, SL West, OR Liang, LY Blencoe, JG Alexiades, V Jacobs, GK Naney, MT Heck, JL AF Phelps, TJ Peters, DJ Marshall, SL West, OR Liang, LY Blencoe, JG Alexiades, V Jacobs, GK Naney, MT Heck, JL TI A new experimental facility for investigating the formation and properties of gas hydrates under simulated seafloor conditions SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID CARBON-DIOXIDE; METHANE HYDRATE; NATURAL-GAS; OCEAN DISPOSAL; DISSOCIATION; PROPANE; GROWTH; PORES; WATER AB A seafloor process simulator (SPS) has been developed for experimental investigations of the physical, geochemical, and microbiological processes affecting the formation and stability of methane and carbon dioxide hydrates at temperatures and pressures corresponding to ocean depths of 2 km. The SPS is a corrosion-resistant pressure vessel whose salient characteristics are: (i) an operating range suitable for study of methane and carbon dioxide hydrates; (ii) numerous access and observation ports, and (iii) a large (0.0722 m(3)) internal volume. Initial experiments have shown that the SPS can be used to produce large amounts of high-purity methane hydrate over a wide range of experimental conditions. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Geosci, Knoxville, TN 37996 USA. Lockheed Martin Energy Syst, Oak Ridge, TN 37831 USA. RP Phelps, TJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM phelpstj1@ornl.gov RI Marshall, Simon/E-9518-2010; phelps, tommy/A-5244-2011; Liang, Liyuan/O-7213-2014 OI Liang, Liyuan/0000-0003-1338-0324 NR 31 TC 25 Z9 26 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 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD FEB PY 2001 VL 72 IS 2 BP 1514 EP 1521 DI 10.1063/1.1334628 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 397JA UT WOS:000166688500046 ER PT J AU Britvich, GI Chumakov, AA Ronningen, RM Blue, RA Heilbronn, LH AF Britvich, GI Chumakov, AA Ronningen, RM Blue, RA Heilbronn, LH TI Measurements of thick target neutron yields and shielding studies using beams of He-4,C-12, and O-16 at 155 MeV/nucleon from the K 1200 cyclotron at the National Superconducting Cyclotron Laboratory (vol 70, pg 2314, 1999) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Correction C1 Superconducting Super Collider Lab, Waxahachee, TX 75165 USA. Inst High Energy Phys, Protvino 142284, Russia. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Britvich, GI (reprint author), Superconducting Super Collider Lab, Waxahachee, TX 75165 USA. RI Heilbronn, Lawrence/J-6998-2013 OI Heilbronn, Lawrence/0000-0002-8226-1057 NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD FEB PY 2001 VL 72 IS 2 BP 1600 EP 1600 DI 10.1063/1.1338484 PG 1 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 397JA UT WOS:000166688500064 ER PT J AU Fang, XW Yang, XJ Littrell, K Niranjanakumari, S Thiyagarajan, P Fierke, CA Sosnick, TR Pan, T AF Fang, XW Yang, XJ Littrell, K Niranjanakumari, S Thiyagarajan, P Fierke, CA Sosnick, TR Pan, T TI The Bacillus subtilis RNase P holoenzyme contains two RNase P RNA and two RNase P protein subunits SO RNA-A PUBLICATION OF THE RNA SOCIETY LA English DT Article DE oligomerization; ribozyme; RNase P; SAXS ID RIBONUCLEASE-P; ESCHERICHIA-COLI; SUBSTRATE-BINDING; CLEAVAGE SITE; M1 RNA; RIBOZYME; PRECURSOR; COMPONENT; ENZYME; ARCHITECTURE AB Ribonuclease P (RNase P) catalyzes the 5' maturation of precursor tRNA transcripts and, in bacteria, is composed of a catalytic RNA and a protein, We investigated the oligomerization state and the shape of the RNA alone and the holoenzyme of Bacillus subtilis RNase P in the absence of substrate by synchrotron small-angle X-ray scattering and affinity retention. The B, subtilis RNase P RNA alone is a monomer; however, the scattering profile changes upon the addition of monovalent ions, possibly suggesting different interdomain angles, To our surprise, the X-ray scattering data combined with the affinity retention results indicate that the holoenzyme contains two RNase P RNA and two RNase P protein molecules. We propose a structural model of the holoenzyme with a symmetrical arrangement of the two RNA subunits, consistent with the X-ray scattering results, This (P RNA)(2)(P protein)(2) complex likely binds substrate differently than the conventional (P RNA)(1)(P protein)(1) complex; therefore, the function of the B. subtilis RNase P holoenzyme may be more diverse than previously thought. These revisions to our knowledge of the RNase P holoenzyme suggest a more versatile role for proteins in ribonucleoprotein complexes. C1 Univ Chicago, Dept Biochem & Mol Biol, Chicago, IL 60637 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. RP Pan, T (reprint author), Univ Chicago, Dept Biochem & Mol Biol, 920 E 58th St, Chicago, IL 60637 USA. RI Littrell, Kenneth/D-2106-2013 OI Littrell, Kenneth/0000-0003-2308-8618 FU NIGMS NIH HHS [GM52993, GM55387, GM57880, R01 GM055387] NR 39 TC 49 Z9 50 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 1355-8382 J9 RNA JI RNA-Publ. RNA Soc. PD FEB PY 2001 VL 7 IS 2 BP 233 EP 241 DI 10.1017/S1355838201001352 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 400RB UT WOS:000166884500008 PM 11233980 ER PT J AU Samatova, NF Potok, TE Leuze, MR AF Samatova, NF Potok, TE Leuze, MR TI Vector space model for the generalized parts grouping problem SO ROBOTICS AND COMPUTER-INTEGRATED MANUFACTURING LA English DT Article; Proceedings Paper CT 10th International Conference on Flexible Automation and Intelligent Manufacturing CY JUN, 2000 CL UNIV MARYLAND, COLLEGE PK, MARYLAND HO UNIV MARYLAND DE group technology; part family formation; cluster analysis ID CELLULAR MANUFACTURING SYSTEM; OPERATION SEQUENCES AB The vector perturbation approach is introduced for addressing the generalized parts grouping problem, identifying part families for a general set of suppliers, not just a single supplier. This method is driven by the need for flexible and lean supply chain systems. A vector space model is used to represent a set of operation sequences as opposed to the traditional matrix and integer programming models in group technology. Using this approach, we find that we are able to generate part groups from 90% of the available parts, in which all the operation sequences are preserved. This contrasts the traditional methods using which only 66% of the available parts can be grouped. Furthermore, a vector representation of operation sequences provides an intuitive means for discovering the natural structure of the part data. From these results, we conclude that this technique can dramatically improve the effectiveness of the entire supply chain. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Samatova, NF (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, POB 2008, Oak Ridge, TN 37831 USA. OI Potok, Thomas/0000-0001-6687-3435 NR 13 TC 3 Z9 3 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0736-5845 J9 ROBOT CIM-INT MANUF JI Robot. Comput.-Integr. Manuf. PD FEB-APR PY 2001 VL 17 IS 1-2 BP 73 EP 80 DI 10.1016/S0736-5845(00)00039-9 PG 8 WC Computer Science, Interdisciplinary Applications; Engineering, Manufacturing; Robotics SC Computer Science; Engineering; Robotics GA 412UB UT WOS:000167571800010 ER PT J AU Matskevich, NI Titov, AA Popova, TL Naumov, VN Nogteva, VV Frolova, GI McCallum, RW AF Matskevich, NI Titov, AA Popova, TL Naumov, VN Nogteva, VV Frolova, GI McCallum, RW TI The thermodynamic characteristics of NdBa2Cu3O7-delta SO RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID CU-O SYSTEM; PHONON CHARACTERISTICS; HEAT-CAPACITY; STABILITY; ELECTRON AB The enthalpies of solution of Nd2O3, BaCO3, CuO, and NdBa2Cu3O7-delta were measured by solution calorimetry at 323.15 K. The results were used to calculate the enthalpies of two different reactions with the participation of the NdBn2Cu3O7-delta phase [Delta H-r degrees (323.15 K)] and the enthalpies of formation of NdBa2Cu3O7-delta [Delta H-f degrees (323.15 K)] from different initial components including monoatomic gases. The heat capacities (C(p)degrees) of NdBa2Cu3O6.98 were measured in the temperature range 100-320 K. The C(p)degrees values were used to calculate the Delta H-r degrees (T) and Delta H-f degrees (T) thermodynamic functions in the temperature range 295.15-123.15 K. The NdBa2Cu3O6.98 compound was found to be thermodynamically stable with respect to the 0.5Nd(2)O(3) + CuO + 2BaCuO(2) mixture in the temperature range 298.15-323.15 K. The Gibbs energies and the entropies of reactions with the participation of the Nd123 phase were calculated. C1 Russian Acad Sci, Inst Inorgan Chem, Siberian Div, Novosibirsk 630090, Russia. Univ Iowa, Ames Lab, Ames, IA USA. RP Matskevich, NI (reprint author), Russian Acad Sci, Inst Inorgan Chem, Siberian Div, Pr Akad Lavrenteva 3, Novosibirsk 630090, Russia. NR 18 TC 0 Z9 0 U1 0 U2 0 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 0036-0244 J9 RUSS J PHYS CHEM+ JI Russ. J. Phys. Chem. PD FEB PY 2001 VL 75 IS 2 BP 145 EP 149 PG 5 WC Chemistry, Physical SC Chemistry GA 403RR UT WOS:000167056700001 ER PT J AU Coutts, TJ AF Coutts, TJ TI An overview of thermophotovoltaic generation of electricity SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article DE thermophotovoltaics; waste heat; cogeneration; selective radiators; TPV systems ID TANDEM SOLAR-CELLS AB This paper provides an overview of the developments in thermophotovoltaic (TPV) generation of electricity that have occurred during relatively recent years (from approximately 1994 to October 1998). The components considered are the semiconductor converter? the radiator, and the means of recirculation of unusable, long-wavelength photons. A short account of the functions of each of these, their mode of operation and their performance is also given. Complete systems are also considered briefly and we conclude by offering some speculation of the future of this technology. (C) 2001 Published by Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Coutts, TJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 35 TC 62 Z9 66 U1 3 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD FEB PY 2001 VL 66 IS 1-4 BP 443 EP 452 DI 10.1016/S0927-0248(00)00206-3 PG 10 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 389JE UT WOS:000166234200055 ER PT J AU Lee, KP Zhang, AP Dang, G Ren, F Han, J Chu, SNG Hobson, WS Lopata, J Abernathy, CR Pearton, SJ Lee, JW AF Lee, KP Zhang, AP Dang, G Ren, F Han, J Chu, SNG Hobson, WS Lopata, J Abernathy, CR Pearton, SJ Lee, JW TI Self-aligned process for emitter- and base-regrowth GaNHBTs and BJTs SO SOLID-STATE ELECTRONICS LA English DT Article DE self-aligned process; AlGaN/GaN HBT; regrown base layer; selective area regrowth ID HETEROJUNCTION BIPOLAR-TRANSISTORS; JUNCTION TRANSISTORS; OPERATION; FABRICATION; SIMULATION AB The development of a self-aligned fabrication process for small emitter contact area (2, x 4 mum(2)) GaN/AlGaN heterojunction bipolar transistors and GaN bipolar junction transistors is described. The process features dielectric-spacer sidewalls, low damage dry etching and selected-area regrowth of p-GaAs(C) on the base contact or n-GaN/ AlGaN on the emitter contact. Series resistance effects are still found to influence the device performance. (C) 2001 Elsevier Science Ltd. All lights reserved. C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Inje Univ, Dept Opt Engn, Kyoungnam 621749, South Korea. RP Ren, F (reprint author), Univ Florida, Dept Chem Engn, POB 116005, Gainesville, FL 32611 USA. NR 15 TC 7 Z9 8 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD FEB PY 2001 VL 45 IS 2 BP 243 EP 247 DI 10.1016/S0038-1101(01)00015-6 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 416HV UT WOS:000167775000005 ER PT J AU Aslin, JL AF Aslin, JL TI Preparticipation health screenings SO STRENGTH AND CONDITIONING JOURNAL LA English DT Editorial Material C1 Univ Calif Los Alamos Natl Lab, Wellness Ctr, Los Alamos, NM 87544 USA. RP Aslin, JL (reprint author), Univ Calif Los Alamos Natl Lab, Wellness Ctr, Los Alamos, NM 87544 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ALLEN PRESS INC PI LAWRENCE PA 810 E 10TH ST, LAWRENCE, KS 66044 USA SN 1073-6840 J9 STRENGTH COND J JI Strength Cond. J. PD FEB PY 2001 VL 23 IS 1 BP 74 EP 75 PG 2 WC Sport Sciences SC Sport Sciences GA 401BV UT WOS:000166907800019 ER PT J AU Layson, AR Thiel, PA AF Layson, AR Thiel, PA TI Testing realistic environments for metal film growth and aging: chemical insights into the effect of oxygen on Ag/Ag(100) SO SURFACE SCIENCE LA English DT Letter DE low energy electron diffraction (LEED); epitaxy, growth, diffusion and migration; silver, oxygen; single crystal epitaxy ID SCANNING TUNNELING MICROSCOPY; SURFACE SELF-DIFFUSION; EPITAXIAL-GROWTH; MASS-FLOW; HYDROGEN; AG(001); O-2; DISSOCIATION; HOMOEPITAXY; DESORPTION AB We study the effect which exposure to molecular oxygen gas can have on the formation and aging of islands in a submonolayer Ag film on Ag(1 0 0). The technique used is high-resolution low-energy electron diffraction, and the surface temperature is 220-250 K. Oxygen has no discernible effect on the average separation of islands resulting from Ag deposition, implying that molecular oxygen does not interact with atomic Ag as it diffuses and nucleates islands on the terraces. However, oxygen serves to accelerate post-deposition coarsening, causing the average island separation to increase rapidly. We show that atomic, not molecular, oxygen is responsible for this effect. Dissociation of the molecule presumably takes place at kink sites, which are plentiful due to the abundance of island edges in the film, and can be triggered either by electron impact or by thermal activation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Thiel, PA (reprint author), Iowa State Univ Sci & Technol, Dept Chem, Gilman Hall, Ames, IA 50011 USA. NR 28 TC 22 Z9 22 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD FEB 1 PY 2001 VL 472 IS 3 BP L151 EP L156 DI 10.1016/S0039-6028(00)00968-7 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 399TF UT WOS:000166827900001 ER PT J AU Magtoto, NP Niu, C Anzaldua, M Kelber, JA Jennison, DR AF Magtoto, NP Niu, C Anzaldua, M Kelber, JA Jennison, DR TI STM-induced void formation at the Al2O3/Ni3Al(111) interface SO SURFACE SCIENCE LA English DT Letter DE scanning tunneling microscopy; density functional calculations; oxidation; corrosion; field effect; aluminum oxide; aluminum; nickel oxides; ceramic thin films; metal-insulator interfaces ID SCANNING-TUNNELING-MICROSCOPY; ALUMINUM-OXIDE FILMS; INITIO MOLECULAR-DYNAMICS; DIELECTRIC-BREAKDOWN; PASSIVE FILMS; ELECTRIC-FIELD; NI3AL(111); JUNCTIONS; AL2O3; PSEUDOPOTENTIALS AB Under ultrahigh vacuum conditions at 300 K, the applied electric field and/or resulting current from an STM tip creates nanoscale voids at the interface between an epitaxial, 7.0 Angstrom thick Al2O3 film and a Ni3Al(1 1 1) substrate. This phenomenon is independent of tip polarity. Constant current (I nA) images obtained at +0.1 V bias and +2.0 V bias voltage (sample positive) reveal that voids are within the metal at the interface and, when small, are capped by the oxide film. Void size increases with time of exposure. The rate of void growth increases with applied bias/field and tunneling current, and increases significantly for field strengths >5 MV/cm, well below the dielectric breakdown threshold of 12 +/- 1 MV/cm. Slower rates of void growth are, however, observed at lower applied field strengths. Continued growth of voids, to similar to 30 Angstrom deep and similar to 500 Angstrom wide, leads to the eventual failure of the oxide overlayer. Density functional theory calculations suggest a reduction-oxidation mechanism: interfacial metal atoms are oxidized via transport into the oxide, while oxide surface Al cations are reduced to admetal species which rapidly diffuse away. This is found to be exothermic in model calculations, regardless of the details of the oxide film structure; thus, the barriers to void formation are kinetic rather than thermodynamic. We discuss our results in terms of mechanisms for the localized pitting corrosion of aluminum, as our results suggest nanovoid formation requires just electric field and current, which are ubiquitous in environmental conditions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ N Texas, Dept Chem, Denton, TX 76203 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Univ N Texas, Dept Chem, POB 305070, Denton, TX 76203 USA. EM kelber@bob.unt.edu NR 38 TC 9 Z9 9 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 EI 1879-2758 J9 SURF SCI JI Surf. Sci. PD FEB 1 PY 2001 VL 472 IS 3 BP L157 EP L163 DI 10.1016/S0039-6028(00)00948-1 PG 7 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 399TF UT WOS:000166827900002 ER PT J AU Jaber, D AF Jaber, D TI Cut costs with condensate return SO TAPPI JOURNAL LA English DT Article C1 US DOE, Alliance Save Energy, Washington, DC 20036 USA. RP Jaber, D (reprint author), US DOE, Alliance Save Energy, 1200 18th St NW,Suite 900, Washington, DC 20036 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU TECH ASSN PULP PAPER IND INC PI NORCROSS PA 15 TECHNOLOGY PARK SOUTH, NORCROSS, GA 30092 USA SN 0734-1415 J9 TAPPI J JI TAPPI J. PD FEB PY 2001 VL 84 IS 2 BP 24 EP 24 PG 1 WC Materials Science, Paper & Wood SC Materials Science GA 400BB UT WOS:000166847800018 ER PT J AU Jaber, D AF Jaber, D TI Opportunities for steam system savings SO TAPPI JOURNAL LA English DT Article C1 US DOE, Alliance Save Energy, Washington, DC 20036 USA. RP Jaber, D (reprint author), US DOE, Alliance Save Energy, 1200 18th St NW,Suite 900, Washington, DC 20036 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU TECH ASSN PULP PAPER IND INC PI NORCROSS PA 15 TECHNOLOGY PARK SOUTH, NORCROSS, GA 30092 USA SN 0734-1415 J9 TAPPI J JI TAPPI J. PD FEB PY 2001 VL 84 IS 2 BP 25 EP 25 PG 1 WC Materials Science, Paper & Wood SC Materials Science GA 400BB UT WOS:000166847800019 ER PT J AU Choi, SUS Yu, WH France, DM Wambsganss, MW AF Choi, SUS Yu, WH France, DM Wambsganss, MW TI A novel multiport cylinder dryer SO TAPPI JOURNAL LA English DT Article C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Univ Illinois, Dept Mech Engn, Chicago, IL 60607 USA. RP Choi, SUS (reprint author), Argonne Natl Lab, Div Energy Technol, Bldg 335,9700 S Cass Ave, Argonne, IL 60439 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU TECH ASSN PULP PAPER IND INC PI NORCROSS PA 15 TECHNOLOGY PARK SOUTH, NORCROSS, GA 30092 USA SN 0734-1415 J9 TAPPI J JI TAPPI J. PD FEB PY 2001 VL 84 IS 2 BP 47 EP 47 PG 1 WC Materials Science, Paper & Wood SC Materials Science GA 400BB UT WOS:000166847800030 ER PT J AU Sen, S Pillai, R Joshi, S Rathi, AK AF Sen, S Pillai, R Joshi, S Rathi, AK TI A mean-variance model for route guidance in advanced traveler information systems SO TRANSPORTATION SCIENCE LA English DT Article ID PATH; NETWORK; TIMES AB Traditional models of route generation are based on choosing routes that minimize expected travel-time between origin and destination. Such approaches do not account for the fact that travelers often incorporate travel-time variability within their decision making. Thus, a route with lower travel-time variability is preferred by some travelers, even if such a route is not one with the lowest mean travel-time. Such traveler behavior is best captured by a multiobjective model in which the choice of a route is based on the mean as well as the variance of the path travel-time. Our route-planning model is intended to help travelers make choices that reflect their decision-making process better. We formulate a network flow multiobjective model in which one of the objectives (expectation) is linear, whereas, the other (variance) is quadratic. Ln order to present the user with a series of options, we solve a series of parametric 0-1 quadratic integer programs. By utilizing the network structure of the problem, we devise an effective algorithm in which the 0-1 quadratic program is solved by using a continuous relaxation together with an enumeration of some selected paths. Finally, we note that the data requirements for the model can be easily satisfied in practice. C1 Univ Arizona, SIE Dept, Tucson, AZ 85721 USA. Oak Ridge Natl Lab, ITS Grp, Oak Ridge, TN 37831 USA. 12 Technol, Irving, TX 75063 USA. RP Sen, S (reprint author), Univ Arizona, SIE Dept, Tucson, AZ 85721 USA. NR 22 TC 50 Z9 53 U1 0 U2 9 PU INST OPERATIONS RESEARCH MANAGEMENT SCIENCES PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2909 USA SN 0041-1655 J9 TRANSPORT SCI JI Transp. Sci. PD FEB PY 2001 VL 35 IS 1 BP 37 EP 49 DI 10.1287/trsc.35.1.37.10141 PG 13 WC Operations Research & Management Science; Transportation; Transportation Science & Technology SC Operations Research & Management Science; Transportation GA 410XR UT WOS:000167466800003 ER PT J AU Duscher, G Buczko, R Pennycook, SJ Pantelides, ST AF Duscher, G Buczko, R Pennycook, SJ Pantelides, ST TI Core-hole effects on energy-loss near-edge structure SO ULTRAMICROSCOPY LA English DT Article; Proceedings Paper CT International Symposium on Spectroscopy of Materials CY MAR 06-10, 2000 CL ROTTAACH EGERN, GERMANY DE electronic structure calculations; core-hole; ELNES; EELS ID X-RAY-ABSORPTION; LOSS SPECTRA; MGO; INTERFACE; EXCITONS; HALIDES; SILICON; OXIDES AB We present first-principles electron energy-loss near-edge structure calculations that incorporate electron-hole interactions and are in excellent agreement with experimental data obtained with X-ray absorption spectroscopy (XAS) and electron energy-loss spectroscopy (EELS). The superior energy resolution in XAS spectra and the new calculations make a compelling case that core-hole effects dominate core-excitation edges of the materials investigated: Si, SiO2, MgO, and SIG. These materials differ widely in the dielectric constant leading to the conclusion that core-hole effects dominate all core-electron excitation spectra in semiconductors and insulators. The implications of the importance of core-holes for simulations of core-electron excitation spectra at interfaces will be discussed. (C), 2001 Elsevier Science B.V. All rights reserved. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN USA. RP Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RI Duscher, Gerd/G-1730-2014 OI Duscher, Gerd/0000-0002-2039-548X NR 24 TC 45 Z9 45 U1 2 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 EI 1879-2723 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD FEB PY 2001 VL 86 IS 3-4 BP 355 EP 362 DI 10.1016/S0304-3991(00)00126-1 PG 8 WC Microscopy SC Microscopy GA 412DE UT WOS:000167538100011 PM 11281155 ER PT J AU Zhang, H Lindberg, SE Marsik, FJ Keeler, GJ AF Zhang, H Lindberg, SE Marsik, FJ Keeler, GJ TI Mercury air/surface exchange kinetics of background soils of the Tahquamenon River watershed in the Michigan Upper Peninsula SO WATER AIR AND SOIL POLLUTION LA English DT Article DE atmosphere; biogeochemical cycling; deposition; dynamic flux chamber; emission; forest; photochemistry ID EMISSIONS; VAPOR; AIR; FLUXES; CHAMBER; TESTS; SURFACES; NEVADA; SITES AB Air/surface exchange of mercury was investigated over background soils at five sites in the Tahquamenon River watershed in the Michigan Upper Peninsula in the summer of 1998. Measurements of Hg fluxes were performed during midday periods using the ORNL Teflon dynamic flux chamber. Mean Hg emission fluxes were 1.4 +/-0.3-2.4 +/-1.0 ng m(-2) hr(-1) for three shaded forest sites and 7.6 +/-1.7 ng m(-2) hr(-1) for an open field site. Hg dry deposition was observed at a heavily shaded forest site over wet soils (mean = -0.3 +/-0.2 ng m(-2) hr(-1)). The overall mean Hg flux was 1.4 +/-1.4 ng m(-2) hr(-1) for the four shaded forest sites. The Hg fluxes observed at these sites are similar to those found at other northern background sites. Significant, rapid response of Hg emission to solar radiation was observed over these background soils. Artificial irrigation over these soils induced immediate and measurable increases in Hg emission. Soil temperature was found to be less influential to Hg air/surface exchange over these heavily shaded forest background soils than we have seen elsewhere. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Oak Ridge Associated Univ, Oak Ridge, TN USA. Univ Michigan, Air Qual Lab, Ann Arbor, MI 48109 USA. RP Zhang, H (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. EM 2hz@ornl.gov NR 27 TC 112 Z9 118 U1 3 U2 30 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0049-6979 J9 WATER AIR SOIL POLL JI Water Air Soil Pollut. PD FEB PY 2001 VL 126 IS 1-2 BP 151 EP 169 DI 10.1023/A:1005227802306 PG 19 WC Environmental Sciences; Meteorology & Atmospheric Sciences; Water Resources SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences; Water Resources GA 396LX UT WOS:000166638800009 ER PT J AU Tokunaga, TK Wan, JM AF Tokunaga, TK Wan, JM TI Surface-zone flow along unsaturated rock fractures SO WATER RESOURCES RESEARCH LA English DT Article ID HYDRAULIC-PROPERTIES; POROUS-MEDIUM; INFILTRATION; PERMEABILITY; FRONT; SOILS AB Although fractures in rock are well recognized as pathways for fast percolation of water, processes which permit fast flow along unsaturated fracture pathways remain to be identified and understood. Earlier aperture-based models of flow in partially saturated fractures permit fast flow only through a continuous network of locally saturated segments. Film flow was recently identified as a mechanism capable of sustaining fast Row along truly unsaturated fractures when the matric potential is very close to zero. Another mechanism for fast flow along unsaturated fractures is introduced in this study, "surface-zone flow," which can be important when the permeability of the rock along fractures (fracture skin) is significantly greater than that of the bulk rock matrix. In such systems the fracture surface zone provides low resistance pathways through which fast flow (relative to the bulk matrix rock) can occur, even when the fractures are at very low water saturation. Initial experimental tests of surface-zone fast flow were performed. Surface-zone fast imbibition of water was measured on a welded tuff and a rhyolite. However, because (1) imbibition rates are also strongly influenced by rock wettability, (2) these initially air-dry rocks exhibited finite contact angles upon exposure to water, and (3) we lack methods to reliably measure permeabilities of thin regions on rock surfaces, quantification of permeability contrasts was not possible in these initial tests. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Tokunaga, TK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd,MS 90-1116, Berkeley, CA 94720 USA. RI Tokunaga, Tetsu/H-2790-2014; Wan, Jiamin/H-6656-2014 OI Tokunaga, Tetsu/0000-0003-0861-6128; NR 49 TC 17 Z9 17 U1 3 U2 8 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 FEB PY 2001 VL 37 IS 2 BP 287 EP 296 DI 10.1029/2000WR900242 PG 10 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 395LX UT WOS:000166582800010 ER PT J AU Davisson, ML Rose, TP AF Davisson, ML Rose, TP TI Interbasin groundwater flow in south central Nevada: A further comment on the discussion between Davisson et al. [1999a, 1999b] and Thomas [1999] - Reply SO WATER RESOURCES RESEARCH LA English DT Editorial Material ID ISOTOPE HYDROLOGY; STABLE ISOTOPES; RADIOCARBON C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Davisson, ML (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-396, Livermore, CA 94550 USA. NR 11 TC 1 Z9 1 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 FEB PY 2001 VL 37 IS 2 BP 435 EP 437 DI 10.1029/2000WR900344 PG 3 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 395LX UT WOS:000166582800024 ER PT J AU Chen, X Shao, ZZ Marinkovic, NS Miller, LM Zhou, P Chance, MR AF Chen, X Shao, ZZ Marinkovic, NS Miller, LM Zhou, P Chance, MR TI Conformation transition kinetics of regenerated Bombyx mori silk fibroin membrane monitored by time-resolved FTIR spectroscopy SO BIOPHYSICAL CHEMISTRY LA English DT Article DE time-resolved FTIR spectroscopy; protein conformation transition; Bombyx mori silk fibroin; beta-sheet conformation ID TRANSFORM INFRARED-SPECTROSCOPY; PHYSICAL-PROPERTIES; SOLID-STATE; RIBONUCLEASE-A; I STRUCTURE; FAST EVENTS; WATER; NMR; TEMPERATURE; DIFFRACTION AB The ethanol-induced conformation transition of regenerated Bombyx mori silk fibroin membrane from a poorly defined to the well ordered state was monitored by time-resolved Fourier transform infrared spectroscopy (FTIR) for the first time. From the analysis of FTIR difference spectra, taken on time scales as short as 6 s and up to 1 h after addition of ethanol. intensity vs. time plots of an increasing band at 1618 cm(-1) were observed indicating formation of a beta -sheet coincident with the loss of intensity of a band at 1668 cm(-1) indicating decreases of random coil and/or silk I structure. Both infrared markers were fitted with identical biphasic exponential decay functions, however, there was a clear burst phase occurring prior to the onset of the observed transitions. The conformation transition process is indicated to either proceed sequentially through (at least) two intermediate states that contain different levels of beta -sheet structure or to have parallel pathways of initial beta -sheet formation followed by a slower 'perfection' phase. The first observed process forms in a burst phase a few seconds after mixing (or even faster), prior to the collection of the first spectrum at 6 s. The second observed process occurs with a time constant of similar to 0.5 min, the intermediate present at this stage then continues with a time constant of 5.5 min completing the observed formation of the beta -sheet. The conformation transition of this slower intermediate is not only indicated by an analysis of the kinetics of the random coil and beta -sheet-specific bands discussed above. it roughly coincides with the appearance of an additional infrared marker at 1695 cm(-1), which may be a marker for p-sheet structure specific to the formation of the perfected structure. The conformation transition of this protein analyzed by infrared spectroscopy provides insight into a part of the fascinating process of cocoon formation in B. mori. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Yeshiva Univ Albert Einstein Coll Med, Ctr Synchrotron Biosci, Bronx, NY 10461 USA. Fudan Univ, Key Lab Mol Engn Polymers, Dept Macromol Sci, Shanghai 200433, Peoples R China. Yeshiva Univ Albert Einstein Coll Med, Dept Physiol & Biophys, Bronx, NY 10461 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Chance, MR (reprint author), Yeshiva Univ Albert Einstein Coll Med, Ctr Synchrotron Biosci, 1300 Morris Pk Ave, Bronx, NY 10461 USA. RI Marinkovic, Nebojsa/A-1137-2016 OI Marinkovic, Nebojsa/0000-0003-3579-3453 FU NCRR NIH HHS [P41-RR-01633] NR 43 TC 160 Z9 167 U1 9 U2 84 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-4622 J9 BIOPHYS CHEM JI Biophys. Chem. PD JAN 31 PY 2001 VL 89 IS 1 BP 25 EP 34 DI 10.1016/S0301-4622(00)00213-1 PG 10 WC Biochemistry & Molecular Biology; Biophysics; Chemistry, Physical SC Biochemistry & Molecular Biology; Biophysics; Chemistry GA 397WQ UT WOS:000166721200003 PM 11246743 ER PT J AU Sigman, ME Barbas, JT Corbett, S Chen, YB Ivanov, I Dabestani, R AF Sigman, ME Barbas, JT Corbett, S Chen, YB Ivanov, I Dabestani, R TI Photochemical reactions of trans-stilbene and 1,1-diphenylethylene on silica gel: mechanisms of oxidation and dimerization SO JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY LA English DT Article DE silica gel; photochemical oxidation; stilbene ID ELECTRON-TRANSFER REACTIONS; DRY SILICA; PRODUCTS; OXYGEN; SIO2; PHOTODECOMPOSITION; ACENAPHTHYLENE; PHOTOLYSIS; ANTHRACENE; INTERFACE AB The photochemical reactions of trans-stilbene and 1,1 -diphenylethylene have been studied at a silica gel-air interface. Irradiation of trans-stilbene leads to the formation of a substantial amount of two dimers, along with the formation of cis-stilbene. phenanthrene and a small amount of benzaldehyde. Photochemical dimer formation from trans-stilbene on silica is promoted by inhomogeneous surface loading and slow surface diffusion. Benzaldehyde arises from a Type II oxidation mechanism. Irradiation of 1.1-diphenylethylene at a silica gel-air interface leads primarily to the formation of benzophenone. The oxidation of 1, 1 -diphenylethylene occurs by a Type I mechanism, as previously proposed [J. Org. Chem. 50 (1985) 149]. The differences in observed photochemistry for these two substituted phenylethylenes on silica is attributed to two factors. Isomerization of trans-stilbene competes efficiently with oxidation, whereas this pathway appears not to be important for 1,1-diphenylethylene. Singlet molecular oxygen is shown to be quenched in solution and at the silica gel-air interface at a faster rate by cis-stilbene than by trans-stilbene or 1,1 -diphenylethylene, thus providing an enhanced Type II oxidation pathway for stilbene. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Valdosta State Univ, Valdosta, GA USA. RP Sigman, ME (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008,MS 6100, Oak Ridge, TN 37831 USA. RI ivanov, ilia/D-3402-2015 OI ivanov, ilia/0000-0002-6726-2502 NR 30 TC 13 Z9 14 U1 0 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 1010-6030 J9 J PHOTOCH PHOTOBIO A JI J. Photochem. Photobiol. A-Chem. PD JAN 31 PY 2001 VL 138 IS 3 BP 269 EP 274 DI 10.1016/S1010-6030(00)00407-X PG 6 WC Chemistry, Physical SC Chemistry GA 397EN UT WOS:000166680500010 ER PT J AU Sorkhabi, O Qi, F Rizvi, AH Suits, AG AF Sorkhabi, O Qi, F Rizvi, AH Suits, AG TI The ultraviolet photochemistry of phenylacetylene and the enthalpy of formation of 1,3,5-hexatriyne SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID SYNCHROTRON-RADIATION; CYCLIZATION REACTIONS; IONIZATION ENERGIES; THERMAL-CONVERSION; ENYNE STRUCTURE; AB-INITIO; HYDROCARBONS; PHOTODISSOCIATION; THERMOCHEMISTRY; DYNAMICS AB The ultraviolet photochemistry of phenylacetylene was studied in a molecular beam at 193 nm. The only primary photofragments observed were HCCH (acetylene) and C6H4 Some of the C6H4 molecules were found to decompose to 1,3,5-hexatriyne and molecular hydrogen. An enthalpy of formation of DeltaH(f) less than or equal to 160 +/- 4 kcal mol(-1) wad determined for 1,3,5-hexatriyne from the energetic threshold for this process, This experimentally determined value agrees well with our ab initio calculations performed at the G2 level of theory. Angular distribution measurements for the HCCH + C6H4 channel yielded an isotropic distribution and were attributed to a long-lived intermediate and ground-state dissociation. An exhaustive search yielded no evidence for the phenyl + ethynyl, dr the atomic hydrogen elimination channels even though these:were observed in the pyrolytic studies of phenylacetylene [Hofmann,J.; Zimmermann, G.; Guthier; K.; Hebgen, P.; Homann, K. ii. Liebigs Ann. 1995, 631, 1995, Guthier, K.; Hebgen, P.; Hofmann, K. H.; Zimmermann, G. Liebigs Ann. 1995, 637, 1995]. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Suits, AG (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RI Qi, Fei/A-3722-2012 NR 64 TC 15 Z9 16 U1 2 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 31 PY 2001 VL 123 IS 4 BP 671 EP 676 DI 10.1021/ja0017312 PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA 396RT UT WOS:000166650900017 PM 11456579 ER PT J AU Cady, CM Gray, GT AF Cady, CM Gray, GT TI Influence of strain rate on the deformation and fracture response of a 6061-T6 Al-50 vol.% Al2O3 continuous-reinforced composite SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE aluminum-matrix composite; loading orientation ID METAL-MATRIX COMPOSITES; MECHANICAL-PROPERTIES; COMPRESSIVE FAILURE; ALUMINUM; STRENGTH; BEHAVIOR; ALLOY; PROPAGATION AB The compressive mechanical properties of an aluminum-matrix composite unidirectionally reinforced with Al2O3 fibers have been measured and characterized as a function of loading orientation. The influence of strain rate and fiber orientation on the deformation and fracture response of a 6061 Al-50 vol.% Al2O3 continuous fiber-reinforced metal matrix composite (MMC) aged to a T6 condition is reported. The stress-strain response of this composite was found to vary substantially as a function of loading orientation: the quasi-static yield changing from nominally 250 MPa transverse to the fibers to similar to 1.7 GPa parallel to the fibers under ideal conditions. increasing the strain rate to 2000 s(-1) was observed to only slightly increase the yield strength of the composite for both orientations. The main failure mechanism has been identified to be kinking, although an upper bound seems to be attained when the fibers reach their compressive strength. The experimental results are consistent with a plastic kinking model for strain hardening composites. The failure response of the composite transverse to the fibers, under both uniaxial stress (quasi-static and dynamic) and uniaxial strain loading. displays a protracted but substantial load drop after yield followed by continued degradation in load carrying capacity. Lack of ideal parallel fiber construction was found to lead to systematic buckling failure of the alumina fibers through the sample under uniaxial loading. (C) 2001 Published by Elsevier Science B.V. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cady, CM (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop G755, Los Alamos, NM 87545 USA. NR 35 TC 15 Z9 15 U1 2 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 2001 VL 298 IS 1-2 BP 56 EP 62 DI 10.1016/S0921-5093(00)01339-3 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 394EM UT WOS:000166511200007 ER PT J AU Beckman, S Cook, BA Akinc, M AF Beckman, S Cook, BA Akinc, M TI Analysis of electrical resistivity of compositions within the Mo-Si-B ternary system, part I: single phase compounds SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE electrical resistivity; intermetallic compounds; molybdenum silicides ID DISILICIDE; MOSI2; MO3SI; FILMS AB Electrical resistivity of nominally single phase polycrystaline compositions within the Mo-Si-B system was characterized as a function of temperature within the range of 25-1500 degreesC. The samples were characterized by X-ray diffraction, and the experimental lattice parameters are shown to agree with literature values. MO5SiB2 (T2), MOB. Mo,Si and Mo,Si, all possess a similar temperature coefficient of resistivity (TCR). T1 phase (Mo5+ySi3-yBy) exhibited a higher resistivity and lower TCR at all temperatures than the parent Mo5Si3. Hall effect measurements showed that boron in T1 is electrically active, increasing the electron concentration an order of magnitude beyond that of Mo,Si,. The higher carrier concentration in T1 is thought to be responsible fbr the observed difference in TCR between the two phases, while microcracking in T1 is believed responsible for the higher resistivity. MoSi2 was found to have a significantly higher TCR compared with all other compositions in this study. The resistivity of all phases is consistent with a description based on semi-metals or low density of states metals. (C) 2001 Elsevier Science B.V, All rights reserved. C1 Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50010 USA. Iowa State Univ, Ames Lab, Ames, IA 50010 USA. RP Cook, BA (reprint author), Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50010 USA. NR 18 TC 9 Z9 10 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 2001 VL 298 IS 1-2 BP 120 EP 126 DI 10.1016/S0921-5093(00)01290-9 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 394EM UT WOS:000166511200015 ER PT J AU Rangaswamy, P Scherer, CP Bourke, MAM AF Rangaswamy, P Scherer, CP Bourke, MAM TI Experimental measurements and numerical simulation of stress and microstructure in carburized 5120 steel disks SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE microstructure and residual stress; carburized disk; predictions ID NEUTRON POWDER DIFFRACTION; TRANSFORMATION PLASTICITY; RESIDUAL-STRESSES; WELDS AB A combined experimental and numerical study of residual stress and microstructure was performed on a carburized disk of 5120 steel. The disk-shaped specimen was carburized and quenched in agitated oil at 71 degreesC. X-ray diffraction combined with electropolishing layer removal was used to determine stresses through the case of the disk, within similar to 1 mm of the surface. Both martensite and retained austenite volume fractions were determined through one flat surface. Rietveld analysis was used to determine the lattice parameters of the constituents at sequential depths. Microstructure and residual stress profiles were compared to predictions. The numerical predictions were from ABAQUS: a finite element code coupled with a user-defined material subroutine (UMAT), that accounted for microstructure evolution. Measured retained austenite values varied from similar to 25 vol.% at the surface to a maximum of similar to 30% at 100 mum. then decreased to 4% at a depth of 600 mum. The numerical simulation predicted a maximum of 25 vol.% at the surface that monotonically decreased to 7% at a depth of 600 mum, and reached a minimum of 4% at 1.0 mm. The maximum measured compressive stress was 380 MPa at 550 mum. compared to the predicted value of 450 MPa at 330 mum. In addition. the carbon profile predicted from the numerical simulation was comparable to the profile obtained from the combustion burnout technique. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Rangaswamy, P (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 26 TC 10 Z9 10 U1 1 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 2001 VL 298 IS 1-2 BP 158 EP 165 DI 10.1016/S0921-5093(00)01292-2 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 394EM UT WOS:000166511200019 ER PT J AU Glassley, WE AF Glassley, WE TI Elemental composition of concentrated brines in subduction zones and the deep continental crust SO PRECAMBRIAN RESEARCH LA English DT Article DE brines; subduction zone; deep continental crust ID SYNTHETIC FLUID INCLUSIONS; OPTIMIZED STANDARD STATE; HYDROTHERMAL FLUIDS; MIDOCEAN RIDGES; BERGEN ARCS; THERMODYNAMIC PROPERTIES; PHASE-EQUILIBRIA; HIGH-PRESSURES; SHEAR ZONES; RICH BRINES AB It has been well established that fluids played an important part in determining chemical characteristics in many crustal terranes. Studies of fluid inclusions in eclogites have established that brines coexisted with the primary mineral assemblages during their metamorphic crystallization. These brines are currently multiply saturated in halide salts, carbonates, oxides, and sulfides. As a first step in quantitatively bounding the composition of the brines during metamorphism, the equilibrium composition of the brines at room temperature were computed using the aqueous speciation codes EQ3/6. The results demonstrate that the brines are high density solutions (ca. 1.4 g/cm(3)) that have ionic strengths of approximately 8 mol, and are approximately 40% dissolved solids, by weight. These are predominately Na- and K-rich brines, with subordinate Ca and Mg. The approximate Na:K:Ca:Mg molar ratios are 4:2:0.5:0.2, but are sensitive to the assumed HCO3- concentrations. Charge balance is primarily maintained by the very high Cl concentrations. These brines bear resemblance to brines analyzed from fluid inclusions in metamorphic rocks reported by Roedder (Roedder, E., 1972. Composition of fluid inclusions. US Geol. Surv. Prof. Paper 440JJ, p. 164). Although these fluids have the potential of acting as significant metasomatic agents in subduction zones and deep crustal environments, their impact will be mineralogically discernible only if the fluid release and movement is channelized. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Glassley, WE (reprint author), Univ Calif Lawrence Livermore Natl Lab, L 202, Livermore, CA 94550 USA. NR 58 TC 7 Z9 8 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-9268 J9 PRECAMBRIAN RES JI Precambrian Res. PD JAN 31 PY 2001 VL 105 IS 2-4 BP 371 EP 383 DI 10.1016/S0301-9268(00)00119-4 PG 13 WC Geosciences, Multidisciplinary SC Geology GA 401LD UT WOS:000166928300016 ER PT J AU Fedorov, A Shi, W Kicska, G Fedorov, E Tyler, PC Furneaux, RH Hanson, JC Gainsford, GJ Larese, JZ Schramm, VL Almo, SC AF Fedorov, A Shi, W Kicska, G Fedorov, E Tyler, PC Furneaux, RH Hanson, JC Gainsford, GJ Larese, JZ Schramm, VL Almo, SC TI Transition state structure of purine nucleoside phosphorylase and principles of atomic motion in enzymatic catalysis SO BIOCHEMISTRY LA English DT Article ID 2.0 ANGSTROM STRUCTURE; ANALOG INHIBITOR; PHOSPHORIBOSYLTRANSFERASE; MECHANISM; INTERMEDIATE; COMPLEX; IONS AB Immuncillin-H [ImmH; (1S)-1 -(9-deazahypoxanthin-9-yl)-1,4-dideoxy-1,4-imino-D-ribitol] is a 23 pM inhibitor of bovine purine nucleoside phosphorylase (PNP) specifically designed as a transition state mimic [Miles, R. W., Tyler, P. C., Furneaux, R. H., Bagdassarian, C. K., and Schramm, V. L. (1998) Biochemistry 37, 8615-8621]. Cocrystals of PNP and the inhibitor are used to provide structural information for each step through the reaction coordinate of PNP. The X-ray crystal structure of free ImmH was solved at 0.9 Angstrom resolution, and a complex of PNP . ImmH . PO4 was solved at 1.5 Angstrom resolution. These structures are compared to previously reported complexes of PNP with substrate and product analogues in the catalytic sites and with the experimentally determined transition state structure. Upon binding, ImmH is distorted to a conformation favoring ribosyl oxocarbenium ion formation. Ribosyl destabilization and transition state stabilization of the ribosyl oxocarbenium ion occur from neighboring group interactions with the phosphate anion and the 5'-hydroxyl of the ribosyl group. Leaving group activation of hypoxanthine involves hydrogen bonds to O6, N1, and N7 of the purine ring. Ordered water molecules provide a proton transfer bridge to O6 and N7 and permit reversible formation of these hydrogen bonds. Contacts between PNP and catalytic site ligands are shorter in the transition state analogue complex of PNP . ImmH . PO4 than in the Michaelis complexes of PNP . inosine . SO4 or PNP . hypoxanthine . ribose 1-PO4. Reaction coordinate motion is dominated by translation of the carbon 1' of ribose between relatively fixed phosphate and purine groups. Purine and pyrimidine phosphoribosyltransferases and nucleoside N-ribosyl hydrolases appear to operate by a similar mechanism. C1 Yeshiva Univ Albert Einstein Coll Med, Dept Biochem, Bronx, NY 10461 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Ind Res Ltd, Lower Hutt, New Zealand. RP Schramm, VL (reprint author), Yeshiva Univ Albert Einstein Coll Med, Dept Biochem, 1300 Morris Pk Ave, Bronx, NY 10461 USA. RI Hanson, jonathan/E-3517-2010; Furneaux, Richard/B-4157-2015 OI Furneaux, Richard/0000-0003-0973-2606 FU NCRR NIH HHS [RR01633] NR 34 TC 168 Z9 169 U1 2 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JAN 30 PY 2001 VL 40 IS 4 BP 853 EP 860 DI 10.1021/bi002499f PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 397LQ UT WOS:000166697500001 PM 11170405 ER PT J AU Cooper, KM Reid, MR Murrell, MT Clague, DA AF Cooper, KM Reid, MR Murrell, MT Clague, DA TI Crystal and magma residence at Kilauea Volcano, Hawaii: Th-230-Ra-226 dating of the 1955 east rift eruption SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Kilauea; Th-230/Ra-226; residence time ID URANIUM SERIES DISEQUILIBRIA; PARTITION-COEFFICIENTS; LAVAS; DIFFERENTIATION; CLINOPYROXENE; SYSTEMS; MELTS; TIME; SIZE; CRYSTALLIZATION AB Previous estimates of crustal storage time of magmas at Kilauea Volcano, Hawaii, range from a few years to a few thousand years, leading to considerable uncertainty in the time scales of processes of magmatic storage and differentiation. We present a new approach for determining minimum magma residence times which involves dating phenocrysts in a magma using Ra-226-Th-230 disequilibria, and apply this approach to the early phase of the 1955 east rift eruption at Kilauea. When fractionation of Ra from Pa (a proxy for initial Ra in the crystals) during crystal growth is considered along with the effects of inclusions in the minerals, the data are consistent with co-precipitation of plagioclase and clinopyroxene from a melt represented by the groundmass at a mean age of 1000(-400)(+300) a. Unless a significant fraction (> 30%) of the crystals are remnants from an earlier batch of evolved magma in the system, these data constrain the minimum magmatic residence time to be similar to 550 yr, considerably longer than most previous estimates of storage time at Kilauea as well as those for some other basaltic systems. For the temperature interval of augite+plagioclase growth in the early 1955 magma, a maximum constant cooling rate of 0.1 degreesC/yr (1 x 10(-5)degreesC/h) is derived from the minimum magmatic residence time of 550 yr. The total magma storage time would be > 2500 yr if this cooling rate applied to the entire thermal history of the magma, although a more complex cooling history where cooling rates were more rapid early in the storage history is permissive of a total residence time which is not much longer than 550 yr, The disparate estimates of magma residence at Kilauea may reflect the uncertainties in the methods of estimation in addition to true variations in storage time for different batches of magma. More work is necessary in order to determine whether a long residence time is characteristic of rift zone lavas and/or of Kilauean lavas in general. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Monterey Bay Aquarium Res Inst, Moss Landing, CA 95039 USA. RP Cooper, KM (reprint author), Univ Calif Los Angeles, Dept Earth & Space Sci, 595 Charles Young Dr E, Los Angeles, CA 90095 USA. RI Cooper, Kari/G-8261-2012; UCLA, SIMS/A-1459-2011 NR 40 TC 67 Z9 69 U1 4 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD JAN 30 PY 2001 VL 184 IS 3-4 BP 703 EP 718 DI 10.1016/S0012-821X(00)00341-1 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 399UC UT WOS:000166829900013 ER PT J AU Mao, GM Sukumaran, S Beaucage, G Saboungi, ML Thiyagarajan, P AF Mao, GM Sukumaran, S Beaucage, G Saboungi, ML Thiyagarajan, P TI PEO-PPO-PEO block copolymer micelles in aqueous electrolyte solutions: Effect of carbonate anions and temperature on the micellar structure and interaction SO MACROMOLECULES LA English DT Article ID ANGLE NEUTRON-SCATTERING; LIGHT-SCATTERING; ETHYLENE-OXIDE; SCANNING CALORIMETRY; TRIBLOCK COPOLYMERS; PROPYLENE-OXIDE; MICELLIZATION; GELATION; BEHAVIOR; SALTS AB The structure and interaction of micelles formed by an amphiphilic triblock copolymer P(EO)(103)-P(PO)(39)-P(EO)(103) (F88) in aqueous electrolyte solutions of potassium carbonate have been investigated using small-angle neutron scattering as functions of temperature and salt concentration. Modeling the SANS data from the copolymer solutions using analytical expressions for the scattering intensity revealed the remarkable effects of carbonate anion concentration and the temperature on the self-assembly of F88 into spherical and cylindrical aggregates and subsequent phase separation. The critical micellization temperature (cmt) of 5 wt % F88 decreases with an increase in the salt concentration, and the cmt approaches ambient temperatures in a solution with 0.1 M K2CO3. An increase in salt concentration also decreases the temperature at which the transition from spherical to cylindrical micelles occurs as well as the phase separation temperature of the copolymer from the solution. These observations clearly indicate that the evolution of the micellar structure and the phase separation are through gradual dehydration of the copolymer chains with an increase in the temperature and/or the salt concentration. The effects of carbonate ions are quite dramatic when compared to those of monovalent ions as the structural transitions occur at a concentration that is lower by an order of magnitude than the published results on monovalent ions. C1 Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Cincinnati, Dept Mat Sci & Engn, Cincinnati, OH 45221 USA. RP Thiyagarajan, P (reprint author), Argonne Natl Lab, Div Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Mao, Guomin/G-3933-2010; Saboungi, Marie-Louise/C-5920-2013 OI Saboungi, Marie-Louise/0000-0002-0607-4815 NR 24 TC 55 Z9 56 U1 3 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JAN 30 PY 2001 VL 34 IS 3 BP 552 EP 558 DI 10.1021/ma001095s PG 7 WC Polymer Science SC Polymer Science GA 395VC UT WOS:000166601100032 ER PT J AU Chen, CL Shen, J Chen, SY Luo, GP Chu, CW Miranda, FA Van Keuls, FW Jiang, JC Meletis, EI Chang, HY AF Chen, CL Shen, J Chen, SY Luo, GP Chu, CW Miranda, FA Van Keuls, FW Jiang, JC Meletis, EI Chang, HY TI Epitaxial growth of dielectric Ba0.6Sr0.4TiO3 thin film on MgO for room temperature microwave phase shifters SO APPLIED PHYSICS LETTERS LA English DT Article ID TITANATE AB Dielectric Ba0.6Sr0.4TiO3 thin films were epitaxially grown on (001) MgO by using pulsed laser ablation. Microstructure studies from x-ray diffraction and electron microscopy suggest that the as-grown films are c-axis oriented with an interface relationship of < 100 > BSTO//< 100 > MgO. A room temperature coupled microwave phase shifter has been developed with a phase shift near 250 degrees at 23.675 GHz under an electrical field of 40 V/mum and a figure of merit of similar to 53 degrees /dB. The performance of the microwave phase shifter based on the epitaxial Ba0.6Sr0.4TiO3 thin films on (001) MgO is close to that needed for practical applications in wireless communications. (C) 2001 American Institute of Physics. C1 Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Glenn Res Ctr, Commun Technol Div, Cleveland, OH 44135 USA. Louisiana State Univ, Dept Mech Engn, Baton Rouge, LA 70803 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Chen, CL (reprint author), Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. NR 17 TC 138 Z9 153 U1 1 U2 13 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 29 PY 2001 VL 78 IS 5 BP 652 EP 654 DI 10.1063/1.1343499 PG 3 WC Physics, Applied SC Physics GA 398CC UT WOS:000166737500031 ER PT J AU Wong, CY AF Wong, CY TI Signatures of quark-gluon plasma phase transition in high-energy nuclear collisions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID HEAVY-ION COLLISIONS; PB-PB COLLISIONS; J/PSI SUPPRESSION; STRANGENESS ENHANCEMENT; PSI' SUPPRESSION; MODEL; QCD; SCATTERING; RAPIDITY; PHOTONS AB In high-energy nuclear collisions, the new phase of the quark-gluon plasma is indicated by an anomalous increase in pressure, an excess of direct photon production, an excess of strangeness production, and an anomalous J/psi, suppression. We review these signatures and discuss how recent high-energy heavy-ion experiments at CERN are consistent with the production of the quark-gluon plasma in high-energy Pb+Pb collisions. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Wong, CY (reprint author), Oak Ridge Natl Lab, Div Phys, POB 2008, Oak Ridge, TN 37831 USA. NR 42 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 22C EP 33C PG 12 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800003 ER PT J AU Zschiesche, D Gerland, L Schramm, S Schaffner-Bielich, J Stocker, H Greiner, W AF Zschiesche, D Gerland, L Schramm, S Schaffner-Bielich, J Stocker, H Greiner, W TI Critical review of quark gluon plasma signals SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID HEAVY-ION COLLISIONS; NUCLEUS-NUCLEUS COLLISIONS; PLUS PB COLLISIONS; J/PSI PRODUCTION; PHOTOPRODUCTION; MULTIPLICITIES; SUPPRESSION; DEPENDENCE; MODEL AB Compelling evidence for a new form of matter has been claimed to be formed in Pb+Pb collisions at SPS. We critically review two suggested signatures for this new state of matter: First the suppression of the J/Psi, which should be strongly suppressed in the QGP by two different mechanisms, the color-screening [1] and the QCD-photoeffect [2]. Secondly the measured particle, in particular strange hadronic, ratios might signal the freeze-out from a quark-gluon phase. C1 Inst Theoret Phys, D-60054 Frankfurt, Germany. Brookhaven Natl Lab, Riken BNL Res Ctr, Upton, NY 11973 USA. RP Zschiesche, D (reprint author), Inst Theoret Phys, D-60054 Frankfurt, Germany. RI Stoecker, Horst/D-6173-2013 OI Stoecker, Horst/0000-0002-3282-3664 NR 27 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 34C EP 40C PG 7 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800004 ER PT J AU Nara, Y AF Nara, Y TI Parton cascade prediction of baryon distribution in ultra-relativistic heavy ion collisions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID ENERGY NUCLEAR COLLISIONS; QCD; SPACE; TIME; MODEL; COLOR AB The baryon distribution is studied by using a parton cascade model which is based on pQCD incorporating hard partonic scattering and dynamical hadronisation scheme. In order to study baryon distribution, baryonic cluster formation is newly implemented as well as hadronic higher resonance states from parton/beam cluster decay. The net baryon number and charged hadron distributions are calculated with different K-factors in which parameters are fixed by elementary p(p) over bar data at E-c.m. = 200 GeV. It is found that baryon stopping behavior at RHIC energies are not consequence of hard parton scattering but soft processes. C1 Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11974 USA. RP Nara, Y (reprint author), Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11974 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 80C EP 83C PG 4 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800011 ER PT J AU Randrup, J AF Randrup, J TI Chiral phase transition in high-energy collisions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID DCC AB High-energy collisions provide unprecedented opportunities for making make global explorations of chiral symmetry in strongly interacting matter. This presentation reviews the general features of the chiral phase diagram, explains the character of the non-equilibrium dynamics occurring in the collision zone and its expected effects, and illustrates suitable methods of analysis by which signals may be extracted from the experimental data. C1 Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Randrup, J (reprint author), Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 100C EP 107C PG 8 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800015 ER PT J AU Rai, G AF Rai, G CA E895 Collaboration TI Hadronic flow in 2-8 a GeV Au+Au collisions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID HEAVY-ION COLLISIONS; RELATIVISTIC NUCLEAR COLLISIONS; ELLIPTIC FLOW; COLLECTIVE EXPANSION; HYDRODYNAMICS; TRANSITION; BEHAVIOR; EQUATION; EMISSION; MATTER AB The E895 experiment has measured Au + Au collisions at beam energies of 2, 4, 6 and 8A GeV. This experiment and its predecessor EOS at the Bevalac have together mapped out excitation functions spanning two decades in beam energy. Our measurements reveal very interesting behaviour of baryon dense nuclear matter which clearly disqualifies some old theoretical notions, while at the same time raising new puzzles. A unified transport model discription presently does not exist which can explain all the data. C1 Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Rai, G (reprint author), Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. NR 46 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 181C EP 189C PG 9 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800027 ER PT J AU Panitkin, SY AF Panitkin, SY CA E895 Colaboration TI Nuclear Imaging: Studying freeze-out with proton and pion correlations SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID HEAVY-ION REACTIONS; COLLISIONS AB We report a particle source imaging analysis based on two-pion correlations in high multiplicity Au + An collisions st beam energies between 2 and 8A GeV. We apply I;he imaging technique introduced by Brown and Danielewicz, which allows a model-independent extraction of source functions with useful accuracy out to relative pion separations of about 20 fm. The extracted source functions have Gaussian shapes. Values of source functions at zero separation are almost constant across the energy range under study. Imaging results are found to be consistent with conventional source parameters obtained from a multidimensional HBT analysis. C1 Kent State Univ, Kent, OH 44242 USA. RP Panitkin, SY (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 190C EP 196C PG 7 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800028 ER PT J AU Odyniec, G AF Odyniec, G TI Strangeness production as a signal for phase transition ... ? SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID RELATIVISTIC NUCLEAR COLLISIONS; LATTICE QCD AB Hadronic yields and their ratios observed in CERN SPS heavy ion experiments with S and Pb beams at 158 GeV/c per nucleon are reviewed. The role of strange particle production in the search for a new phase of matter, in both experiment and theory, is discussed. C1 Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Odyniec, G (reprint author), Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. NR 28 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 197C EP 204C PG 8 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800029 ER PT J AU Moretto, LG Elliott, JB Phair, L Wozniak, GJ AF Moretto, LG Elliott, JB Phair, L Wozniak, GJ TI Nuclear multifragmentation along the liquid-vapor univariant equilibrium line and beyond SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID 1A GEV GOLD; PERCOLATION PHENOMENA; REDUCIBILITY; EMISSION; DYNAMICS; CARBON AB Reducibility (stochasticity in multiplicity distributions) and thermal scaling (one fragment emission probabilities are Boltzmann factors) are empirical features of nuclear multifragmentation shared by the Fisher Droplet Model and by percolation. A new scaling feature (1/Z scaling) of the mt parameter of the binomial distribution shows that the fragmentation space is uniformly explored and leads to a determination of the source size. C1 Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Moretto, LG (reprint author), Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 239C EP 252C PG 14 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800033 ER PT J AU d'Enterria, DG Aphecetche, L Chbihi, A Delagrange, H Diaz, J van Goethem, MJ Hoefman, M Huisman, H Kugler, A Loehner, H Martinez, G Ortega, R Ostendorf, R Schadmand, S Schutz, Y Siemssen, R Stracener, D Tlusty, P Turrisi, R Volkerts, M Wagner, V Wilschut, H Yahlali, N AF d'Enterria, DG Aphecetche, L Chbihi, A Delagrange, H Diaz, J van Goethem, MJ Hoefman, M Huisman, H Kugler, A Loehner, H Martinez, G Ortega, R Ostendorf, R Schadmand, S Schutz, Y Siemssen, R Stracener, D Tlusty, P Turrisi, R Volkerts, M Wagner, V Wilschut, H Yahlali, N TI Thermal bremsstrahlung probing the thermodynamical state of multifragmenting systems SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 3rd Catania Relativistic Ion Studies (CRIS 2000) CY MAY 22-26, 2000 CL ACI CASTELLO, ITALY SP Ist Nazl Fis Nucl, Univ Catania, Ctr Siciliano Fis Nucl Struttura Mat, Comune Acicastello, Comune Catania, Azienda Autonoma Incremento Turist Provincia Reg Catania, Presidenza Assemblea Reg Siciliana, Governo Reg Regione Sicilia, Banca Roma, Catania, Shougun Travel Agcy, Gruppo Averna, Distilleria F lli Russo snc, Dais, Torrisi, Compagnia Meridionale Caffe, Catania ID HEAVY-ION COLLISIONS; NUCLEI AB Inclusive and exclusive hard-photon (E-gamma > 30 MeV) production in five different heavy-ion reactions (Ar-36+Au-197, Ag-107, Ni-58, C-12 at 60A MeV and Xe-129+Sn-120 at 50A MeV) has been studied coupling the TAPS photon spectrometer with several charged-particle multidetectors covering more than 80% of 4 pi. The measured spectra, slope parameters and source velocities as well as their target-dependence, confirm the existence of thermal bremsstrahlung emission from secondary nucleon-nucleon collisions that accounts for roughly 20% of the total hard-photon yield. The thermal slopes are a direct measure of the temperature of the excited nuclear systems produced during the reaction. C1 Kernfys Versneller Inst, NL-9747 AA Groningen, Netherlands. Inst Nucl Phys, Rez 25068, Czech Republic. Univ Valencia, CSIC, IFIC, E-46100 Burjassot, Spain. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Giessen, Inst Phys 2, D-35392 Giessen, Germany. Univ Autonoma Barcelona, Grp Fis Radiac, Bellaterra, Catalonia, Spain. GANIL, F-14076 Caen 5, France. RP d'Enterria, DG (reprint author), SUBATECH, 4 Rue A Kastler, F-44307 Nantes 3, France. RI Diaz, Jose/B-3454-2012; Turrisi, Rosario/H-4933-2012; Lohner, Herbert/B-2397-2014; YAHLALI, NADIA/L-1880-2014 OI Diaz, Jose/0000-0002-7239-223X; Lohner, Herbert/0000-0002-7441-739X; YAHLALI, NADIA/0000-0003-2184-0132 NR 11 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 29 PY 2001 VL 681 BP 291C EP 294C PG 4 WC Physics, Nuclear SC Physics GA 395NE UT WOS:000166585800039 ER PT J AU Alavi-Harati, A Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barker, AR Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hamm, J Hanagaki, K Hidaka, S Hsiung, YB Jejer, V Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL Mikelsons, P Monnier, E Nakaya, T Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Shields, J Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Turner, SE Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED AF Alavi-Harati, A Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barker, AR Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hamm, J Hanagaki, K Hidaka, S Hsiung, YB Jejer, V Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL Mikelsons, P Monnier, E Nakaya, T Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Shields, J Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Turner, SE Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED TI Study of the K-L(0) -> pi(+)pi(-)gamma direct emission vertex SO PHYSICAL REVIEW LETTERS LA English DT Article ID CP VIOLATION; KAON DECAYS; K-L->PI(+)PI(-)E(+)E(-) AB We have perfomed studies of the K-L(0) --> pi (+) pi (-) gamma direct emission (DE) and inner Bremsstrahlung (IB) vertices, based on data collected by KTeV during the 1996 Fermilab fixed target run. We find a(1)/a(2) = -0.737 +/- 0.034 GeV2 for the DE form-factor parameter in the rho -propagator parametrization, and report on fits of the form factor to linear and quadratic functions as well. We concurrently measure Gamma (K-L(0) --> pi (+) pi (-) gamma ,E-gamma*: > 20 MeV)/Gamma (K-L(0) --> pi (+) pi (-)) = (20.8 +/- 0.3) x 10(-3), and a K-L(0) --> pi (+) pi (-) gamma DE/(DE + IB) branching ratio of 0.683 +/- 0.011. C1 Rutgers State Univ, Piscataway, NJ 08855 USA. Rice Univ, Houston, TX 77005 USA. Osaka Univ, Toyonaka, Osaka 560, Japan. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Elmhurst Coll, Elmhurst, IL 60126 USA. Univ Colorado, Boulder, CO 80309 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Arizona, Tucson, AZ 85721 USA. Univ Virginia, Charlottesville, VA 22901 USA. Univ Wisconsin, Madison, WI 53706 USA. Montana State Univ, Bozeman, MT 59717 USA. RP Belz, J (reprint author), Rutgers State Univ, Piscataway, NJ 08855 USA. NR 16 TC 15 Z9 15 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 29 PY 2001 VL 86 IS 5 BP 761 EP 764 DI 10.1103/PhysRevLett.86.761 PG 4 WC Physics, Multidisciplinary SC Physics GA 396FN UT WOS:000166625800004 PM 11177934 ER PT J AU Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GF Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B Magnin, J Massafferri, A MayTal-Beck, S Meadows, B Neto, JRT Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C AF Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GF Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B Magnin, J Massafferri, A MayTal-Beck, S Meadows, B Neto, JRT Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C TI Study of the D-s(+) -> pi(-)pi(+)pi(+) decay and measurement of f(0) masses and widths SO PHYSICAL REVIEW LETTERS LA English DT Article ID DALITZ PLOTS AB From a sample of 848 +/- 44 D-s(+) --> pi (-) pi (+) pi (+) decays, we find Gamma (D-s(+) --> pi (-) pi (+) pi (+))/Gamma (D-s(+)--> phi pi (+)) = 0.245 +/- 0.028(-0.012)(+0.019). Using a Dalitz plot analysis of this three body decay, we find significant contributions from the channels rho (0)(770)pi (+), rho (0)(1450)pi (+,) f(0)(980)pi (+), f(2)(1270)pi (+), and f(0)(1370)pi (+). We also present the values obtained for masses and widths of the resonances f(0)(980) and f(0)(1370). C1 Univ Mississippi Oxford, University, MS 38677 USA. Univ Massachusetts, Amherst, MA 01003 USA. Kansas State Univ, Manhattan, KS 66506 USA. IIT, Chicago, IL 60616 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. CINVESTAV, Mexico City 14000, DF, Mexico. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Princeton Univ, Princeton, NJ 08544 USA. Univ Autonoma Puebla, Puebla 72570, Mexico. Univ S Carolina, Columbia, SC 29208 USA. Stanford Univ, Stanford, CA 94305 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Tufts Univ, Medford, MA 02155 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. RP Aitala, EM (reprint author), Univ Mississippi Oxford, University, MS 38677 USA. RI Gobel Burlamaqui de Mello, Carla /H-4721-2016; Fernandez Tellez, Arturo/E-9700-2017; de Mello Neto, Joao/C-5822-2013 OI Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X; Fernandez Tellez, Arturo/0000-0003-0152-4220; de Mello Neto, Joao/0000-0002-3234-6634 NR 11 TC 168 Z9 168 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 29 PY 2001 VL 86 IS 5 BP 765 EP 769 DI 10.1103/PhysRevLett.86.765 PG 5 WC Physics, Multidisciplinary SC Physics GA 396FN UT WOS:000166625800005 PM 11177935 ER PT J AU Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GE Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B Magnin, J Massafferri, A MayTal-Beck, S Meadows, B Neto, JRTD Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C AF Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GE Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B Magnin, J Massafferri, A MayTal-Beck, S Meadows, B Neto, JRTD Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C TI Experimental evidence for a light and broad scalar resonance in D+ -> pi(-)pi(+)pi(+) decay SO PHYSICAL REVIEW LETTERS LA English DT Article ID PARTIAL-WAVE ANALYSIS; 450 GEV/C; SYSTEM AB From a sample of 1172 +/- 61 D+ --> pi (-) pi (+) pi (+) decays, we find Gamma (D+ --> pi (-) pi (+) pi (+))/Gamma (D+ --> K- pi (+) pi (+)) = 0.0311 +/- 0.0018(-0.0026)(+0.0016). Using a coherent amplitude analysis to fit the Dalitz plot of these decays, we find strong evidence that a scalar resonance of mass 478(-23)(+24) +/- 17 MeV/c(2) and width 324(-40)(+42) +/- LI meV/c(2) accounts for approximately half or all decays. C1 Univ Mississippi Oxford, University, MS 38677 USA. Univ Massachusetts, Amherst, MA 01003 USA. Kansas State Univ, Manhattan, KS 66506 USA. IIT, Chicago, IL 60616 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. CINVESTAV, Mexico City 14000, DF, Mexico. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Princeton Univ, Princeton, NJ 08544 USA. Univ Autonoma Puebla, Puebla 72570, Mexico. Univ S Carolina, Columbia, SC 29208 USA. Stanford Univ, Stanford, CA 94305 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Tufts Univ, Medford, MA 02155 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. RP Aitala, EM (reprint author), Univ Mississippi Oxford, University, MS 38677 USA. RI Gobel Burlamaqui de Mello, Carla /H-4721-2016; Fernandez Tellez, Arturo/E-9700-2017; de Mello Neto, Joao/C-5822-2013 OI Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X; Fernandez Tellez, Arturo/0000-0003-0152-4220; de Mello Neto, Joao/0000-0002-3234-6634 NR 19 TC 309 Z9 313 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 29 PY 2001 VL 86 IS 5 BP 770 EP 774 DI 10.1103/PhysRevLett.86.770 PG 5 WC Physics, Multidisciplinary SC Physics GA 396FN UT WOS:000166625800006 PM 11177936 ER PT J AU Mattioli, M Fournier, KB Carraro, L Coffey, I Giroud, C Lawson, K Monier-Garbet, P O'Mullane, M Ongena, J Puiatti, ME Sattin, F Scarin, P Valisa, M AF Mattioli, M Fournier, KB Carraro, L Coffey, I Giroud, C Lawson, K Monier-Garbet, P O'Mullane, M Ongena, J Puiatti, ME Sattin, F Scarin, P Valisa, M TI Experimental and simulated argon spectra in the 2.3-3.4 nm region from tokamak plasmas SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID LOW-DENSITY PLASMA; X-RAY; RATE COEFFICIENTS; ELECTRON-IMPACT; IONS; IONIZATION; ATOMS; SPECTROSCOPY; TEMPERATURE; TRANSPORT AB Experimental argon spectra in the 2.3-3.4 nm region from the Jet tokamak on a single null divertor configuration have been simulated. The spectra include lines from five ionization states, namely from Ar15+ Li-like to Ar11+ N-like ions, Collisional-radiative models have been constructed for these five Ar ions, considering electron collisional excitation and radiative decay as the populating processes of the excited states. These models give photon emission coefficients for the emitted lines at electron density and temperature values corresponding to the experimental situations. Impurity modelling is performed using a one-dimensional (1D) impurity transport code, calculating the steady-state radial distribution of the Ar ions. The Ar line brightnesses are evaluated in a post-processing subroutine and simulated spectra are obtained. The parts of the spectra corresponding to a single-ionization state do not depend on the experimental conditions and show good agreement except for the amplitude of the simulated 2s-3p Ar xvi line and the shape of the simulated 2.50 nm feature (composed of Ar xvi and Ar xv lines). On the other hand, the superposition of these spectra depends on the experimental conditions, as a consequence of the fact that the ion charge distribution depends not only on the radial profiles of the electron density and temperature, but also of the impurity transport coefficients, Simulations of the Ar spectra (including transport) give confidence in the atomic physics calculations; moreover, they allow the determination of the transport coefficients in the plasma region emitting the considered ionization states, i,e. at the interior of the last closed magnetic surface (LCMS). For a correct simulation of the amplitudes of the spectral features it is necessary to include a transport barrier inside the LCMS. As far as the atomic physics is concerned, we report improved wavelengths for Arxv transitions and we benchmark photon emission coefficients for XUV transitions in highly ionized argon. C1 Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Consorzio RFX, I-35127 Padua, Italy. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Queens Univ Belfast, Belfast BT7 1NN, Antrim, North Ireland. Ctr Etud Cadarache, CEA Fus, Associat Euratom, F-13108 St Paul Durance, France. UKAEA Euratom Fus Assoc, Culham Lab, Abingdon OX14 3EDB, Oxon, England. Univ Strathclyde, Glasgow G4 0NG, Lanark, Scotland. Ecole Royal Mil, Euratom Belgian State Assoc, B-1000 Brussels, Belgium. RP Mattioli, M (reprint author), Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. RI Sattin, Fabio/B-5620-2013 NR 29 TC 16 Z9 17 U1 1 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD JAN 28 PY 2001 VL 34 IS 2 BP 127 EP 142 DI 10.1088/0953-4075/34/2/301 PG 16 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 427UE UT WOS:000168423200006 ER PT J AU Wilson, KB Hanson, PJ Mulholland, PJ Baldocchi, DD Wullschleger, SD AF Wilson, KB Hanson, PJ Mulholland, PJ Baldocchi, DD Wullschleger, SD TI A comparison of methods for determining forest evapotranspiration and its components: sap-flow, soil water budget, eddy covariance and catchment water balance SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article DE evapotranspiration; eddy covariance; catchment water balance ID BROAD-LEAVED FOREST; DECIDUOUS FOREST; MICROMETEOROLOGICAL METHODS; SEASONAL-VARIATIONS; USE EFFICIENCY; GAS-EXCHANGE; PINE FOREST; TRANSPIRATION; TREES; EVAPORATION AB A multi-year, multi-technique study was conducted to measure evapotranspiration and its components within an uneven-aged mixed deciduous forest in the Southeastern United States. Four different measurement techniques were used, including soil water budget (1 year), sap flow (2 years), eddy covariance (5 years), and catchment water budget (31 years). Annual estimates of evapotranspiration were similar for the eddy covariance and catchment water balance techniques, averaging 571 +/- 16 mm (eddy covariance) and 582 +/- 28 mm (catchment water balance) per year over a 5-year period. There were qualitative similarities between sap flow and eddy covariance estimates on a daily basis, and sap flow estimates of transpiration were about 50% of annual evapotranspiration estimated from eddy covariance and catchment studies. Soil evaporation was estimated using a second eddy covariance system below the canopy, and these measurements suggest that soil evaporation explains only a small portion of the difference between sap flow estimates of transpiration and eddy covariance and catchment water budget estimates of evapotranspiration. Convergence of the catchment water balance and eddy covariance methods and moderately good energy balance closure suggests that the sap flow estimates could be low, unless evaporation of canopy-intercepted water was especially large. The large species diversity and presence of ring-porous trees at our site may explain the difficulty in extrapolating sap flow measurements to the spatial scales representative of the eddy covariance and catchment water balance methods. Soil water budget estimates were positively correlated with eddy covariance and sap flow measurements, but the data were highly variable and in error under conditions of severe surface dryness and after rainfall events. (C) 2001 Elsevier Science B.V. All rights reserved. C1 NOAA, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. RP Wilson, KB (reprint author), NOAA, Atmospher Turbulence & Diffus Div, POB 2456, Oak Ridge, TN 37831 USA. RI Hanson, Paul J./D-8069-2011; Wullschleger, Stan/B-8297-2012; Mulholland, Patrick/C-3142-2012; Baldocchi, Dennis/A-1625-2009 OI Hanson, Paul J./0000-0001-7293-3561; Wullschleger, Stan/0000-0002-9869-0446; Baldocchi, Dennis/0000-0003-3496-4919 NR 57 TC 311 Z9 343 U1 11 U2 148 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD JAN 27 PY 2001 VL 106 IS 2 BP 153 EP 168 DI 10.1016/S0168-1923(00)00199-4 PG 16 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 390YT UT WOS:000166327900006 ER PT J AU Rotman, DA Tannahill, JR Kinnison, DE Connell, PS Bergmann, D Proctor, D Rodriguez, JM Lin, SJ Rood, RB Prather, MJ Rasch, PJ Considine, DB Ramaroson, R Kawa, SR AF Rotman, DA Tannahill, JR Kinnison, DE Connell, PS Bergmann, D Proctor, D Rodriguez, JM Lin, SJ Rood, RB Prather, MJ Rasch, PJ Considine, DB Ramaroson, R Kawa, SR TI Global Modeling Initiative assessment model: Model description, integration, and testing of the transport shell SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; 3-DIMENSIONAL MODEL; MIDDLE ATMOSPHERE; TRACER TRANSPORT; STRATOSPHERE; AIRCRAFT; TROPOSPHERE; SIMULATION; CHEMISTRY; OZONE AB We describe the three-dimensional global stratospheric chemistry model developed under the NASA Global Modeling Initiative (GMI) to assess the possible environmental consequences from the emissions of a fleet of proposed high-speed civil transport aircraft. This model was developed through a unique collaboration of the members of the CMI team. Team members provided computational modules representing various physical and chemical processes, and analysis of simulation results through extensive comparison to observation. The team members' modules were integrated within a computational framework that allowed transportability and simulations on massively parallel computers. A unique aspect of this model framework is the ability to interchange and intercompare different submodules to assess the sensitivity of numerical algorithms and model assumptions to simulation results. In this paper, we discuss the important attributes of the GMI effort and describe the CMI model computational framework and the numerical modules representing physical and chemical processes. As an application of the concept, we illustrate an analysis of the impact of advection algorithms on the dispersion of a NOy-like source in the stratosphere which mimics that of a fleet of commercial supersonic transports thigh-speed civil transport (HSCT)) flying between 17 and 20 km. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA. Off Natl Etud & Rech Aerosp, F-92322 Chatillon, France. Univ Miami, Dept Marine & Atmospher Chem, Miami, FL 33149 USA. RP Rotman, DA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Mail Stop Li-103, Livermore, CA 94550 USA. RI Bergmann, Daniel/F-9801-2011; Kawa, Stephan/E-9040-2012; Rodriguez, Jose/G-3751-2013; Rood, Richard/C-5611-2008 OI Bergmann, Daniel/0000-0003-4357-6301; Rodriguez, Jose/0000-0002-1902-4649; Rood, Richard/0000-0002-2310-4262 NR 61 TC 44 Z9 44 U1 2 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JAN 27 PY 2001 VL 106 IS D2 BP 1669 EP 1691 DI 10.1029/2000JD900463 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 395TB UT WOS:000166596400016 ER PT J AU Kinnison, DE Connell, PS Rodriguez, JM Rotman, DA Considine, DB Tannahill, J Ramaroson, R Rasch, PJ Douglass, AR Baughcum, SL Coy, L Waugh, DW Kawa, SR Prather, MJ AF Kinnison, DE Connell, PS Rodriguez, JM Rotman, DA Considine, DB Tannahill, J Ramaroson, R Rasch, PJ Douglass, AR Baughcum, SL Coy, L Waugh, DW Kawa, SR Prather, MJ TI The Global Modeling Initiative assessment model: Application to high-speed civil transport perturbation SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; MIDDLE ATMOSPHERE; LOWER STRATOSPHERE; AIRCRAFT; NITROGEN; CHEMISTRY; CONTRAST; RADICALS; DIOXIDE; OXIDE AB The NASA Atmospheric Effects of Aviation Project (AEAP) Global Modeling Initiative (GMI) three-dimensional (3-D) chemical transport model (CTM) was applied to assess the impact of a fleet of high-speed civil transports (HSCTs) on abundances of stratospheric ozone, total inorganic nitrogen (NOy), and H2O. This model is specifically designed to incorporate a diversity of approaches to chemical and physical processes related to the stratosphere in a single computing framework, facilitating the analysis of model component differences, modeling intercomparison and comparison with data. A proposed HSCT fleet scenario was adopted, in which the aircraft cruise in the lower stratosphere, emitting nitrogen oxides (NOx) and water (H2O). The model calculated an HSCT-induced change in Northern and Southern Hemisphere total column ozone of +0.2% and +0.05%, respectively. This change is the result of a balance between an increase in local ozone below approximately 25 km and a decrease above this altitude. When compared to available NOy observations, we find that the model consistently underestimates lower stratospheric NOy. This discrepancy is consistent with the model bias toward less negative ozone impact, when compared to results from other models. Additional analysis also indicates that for an HSCT assessment it is equally important for a model to accurately represent the lower stratospheric concentrations of ozone and H2O. The GMI model yields good agreement In comparisons to ozone data For present-day conditions, while H2O is constrained by climatology as much as possible; thus no further biases would be expected from these comparisons. Uncertainties due to discrepancies in the calculated age of ail compared to that derived from measurements, and of the impact of emissions on heterogeneous and polar chemistry, are difficult to evaluate at this point. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Boeing Co, Seattle, WA 98124 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA. Off Natl Etud & Rech Aerosp, F-92322 Chatillon, France. Univ Miami, Dept Marine & Atmospher Chem, Miami, FL 33149 USA. Johns Hopkins Univ, Dept Earth & Planetary Sci, Baltimore, MD USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. RP Kinnison, DE (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. RI Douglass, Anne/D-4655-2012; Kawa, Stephan/E-9040-2012; Rodriguez, Jose/G-3751-2013; Waugh, Darryn/K-3688-2016 OI Rodriguez, Jose/0000-0002-1902-4649; Waugh, Darryn/0000-0001-7692-2798 NR 60 TC 17 Z9 17 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JAN 27 PY 2001 VL 106 IS D2 BP 1693 EP 1711 DI 10.1029/2000JD900406 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 395TB UT WOS:000166596400017 ER PT J AU Murthy, KHM Smith, SA Ganesh, VK Judge, KW Mullin, N Barlow, PN Ogata, CM Kotwal, GJ AF Murthy, KHM Smith, SA Ganesh, VK Judge, KW Mullin, N Barlow, PN Ogata, CM Kotwal, GJ TI Crystal structure of a complement control protein that regulates both pathways of complement activation and binds heparan sulfate proteoglycans SO CELL LA English DT Article ID INFLAMMATION MODULATORY PROTEIN; FIBROBLAST GROWTH-FACTOR; VACCINIA VIRUS; FACTOR-H; C4B-BINDING PROTEIN; C3; RESIDUES; MODULES; SITES; CD21 AB Vaccinia virus complement control protein (VCP) inhibits both pathways of complement activation through binding the third and fourth components. A homolog of mammalian regulators of complement activation, its ability to bind heparin endows VCP with additional activities of significance to viral infectivity. The structure of VCP reveals a highly extended molecule with a putative heparin recognition site at its C-terminal end. A second duster of positive charges provides a possibly overlapping binding site for both heparin and complement components. Experiments suggested by the structure indicate that VCP can bind heparin and control complement simultaneously. This, the structure of any intact regulator of complement activation, along with attendant functional insights, will stimulate the design of new therapeutic inhibitors of complement. C1 Univ Alabama, Ctr Biophys Sci & Engn, Birmingham, AL 35294 USA. Univ Louisville, Sch Med, Dept Microbiol & Immunol, Louisville, KY 40292 USA. Univ Edinburgh, Edinburgh Ctr Prot Technol, Edinburgh EH9 3JJ, Midlothian, Scotland. Brookhaven Natl Lab, Howard Hughes Med Inst, Upton, NY 11973 USA. RP Murthy, KHM (reprint author), Univ Alabama, Ctr Biophys Sci & Engn, 1918 Univ Blvd, Birmingham, AL 35294 USA. RI Barlow, Paul/G-2853-2011 NR 62 TC 111 Z9 111 U1 0 U2 0 PU CELL PRESS PI CAMBRIDGE PA 1050 MASSACHUSETTES AVE, CIRCULATION DEPT, CAMBRIDGE, MA 02138 USA SN 0092-8674 J9 CELL JI Cell PD JAN 26 PY 2001 VL 104 IS 2 BP 301 EP 311 DI 10.1016/S0092-8674(01)00214-8 PG 11 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 400PB UT WOS:000166879700013 PM 11207370 ER PT J AU Jandera, P Skavrada, M Andel, L Komers, D Guiochon, G AF Jandera, P Skavrada, M Andel, L Komers, D Guiochon, G TI Description of adsorption equilibria in liquid chromatography systems with binary mobile phases SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 13th International Symposium on Preparative and Process Chromatography CY MAY 14-17, 2000 CL WASHINGTON, D.C. SP St Louis Chromatog Discuss Grp, Washington Chromatog Discuss Grp DE adsorption isotherms; mobile phase composition; phenols; benzophenone; cholesterol ID OVERLOADED CHROMATOGRAPHY; SINGLE-COMPONENT; ISOTHERMS; SEPARATION; RETENTION; PROFILE; MODELS; SOLUTE AB Adsorption of some simple compounds from pure and mixed solvents and of some solvents from mixed binary solvent mixtures on columns used in normal-phase, aqueous-organic and non-aqueous liquid chromatography was investigated. The distribution of the compounds between the liquid and the stationary phase is affected by the composition of the solvent mixture. Although preferential sorption of stronger solvents can often be described by the Langmuir isotherm, significant deviations are observed in some systems. A model was suggested accounting for the deviations from Langmuir isotherm by association on already adsorbed molecules. In most systems studied in this work, a simple competitive Langmuir isotherm did not provide a good fit to the experimental distribution data from mixed solvents when competition between the solute and the strong solvent for the adsorption sites was considered. A competitive isotherm taking into account possible association of solute on its own already adsorbed molecules and on the adsorbed molecules of strong solvent improves the fit to the experimental distribution data and enables description of the distribution data in dependence on the concentration of the strong solvent in mixed solvents in normal-phase, aqueous-organic and non-aqueous reversed-phase systems. Even though we need more data to prove the validity of the present model, we observe a good qualitative agreement of the experimental isotherm coefficients with the relative strength of the interactions expected in various chromatographic systems employing mixed solvents. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Pardubice, Dept Analyt Chem, Pardubice 53210, Czech Republic. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Jandera, P (reprint author), Univ Pardubice, Dept Analyt Chem, Nam Legii 565, Pardubice 53210, Czech Republic. NR 26 TC 27 Z9 27 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JAN 26 PY 2001 VL 908 IS 1-2 BP 3 EP 17 DI 10.1016/S0021-9673(00)01003-7 PG 15 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 397NG UT WOS:000166701300002 PM 11218132 ER PT J AU Mihlbachler, K Fricke, J Yun, T Seidel-Morgenstern, A Schmidt-Traub, H Guiochon, G AF Mihlbachler, K Fricke, J Yun, T Seidel-Morgenstern, A Schmidt-Traub, H Guiochon, G TI Effect of the homogeneity of the column set on the performance of a simulated moving bed unit I. Theory SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 13th International Symposium on Preparative and Process Chromatography CY MAY 14-17, 2000 CL WASHINGTON, D.C. SP St Louis Chromatog Discuss Grp, Washington Chromatog Discuss Grp DE simulated moving bed chromatography; retention factors; porosity ID ADSORPTION SEPARATION PROCESSES; CHROMATOGRAPHY; COUNTERCURRENT; DESIGN; RESOLUTION AB Although it is impossible to manufacture identical columns for use in a simulated moving bed (SMB) process, theoretical studies assume that all the columns in an SMB unit have identical characteristics. In practice, calculations in modeling and optimization studies are made with the average values of each column parameter set. In this report, the effects on SMB process performance caused by column-to-column fluctuations of the parameters are discussed, As a first step, we show how the differences in porosity of the columns may be taken into account with a revised set of separation conditions. Reductions in the purity of the extract and the raffinate streams are quantitatively related to the column-to-column fluctuations of the retention times of the two components arising from these porosity differences. For the sake of simplicity, the discussion first addresses the case of a four-column SMB operating under linear conditions. Then, the scope is extended to the cases of SMB units incorporating several columns in each section and to SMB units operating under nonlinear conditions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Magdeburg, Dept Chem Engn, D-39106 Magdeburg, Germany. Univ Dortmund, Dept Chem Engn, D-4600 Dortmund, Germany. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. OI Seidel-Morgenstern, Andreas/0000-0001-8595-7810 NR 26 TC 26 Z9 26 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JAN 26 PY 2001 VL 908 IS 1-2 BP 49 EP 70 DI 10.1016/S0021-9673(00)00935-3 PG 22 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 397NG UT WOS:000166701300005 PM 11218134 ER PT J AU Reidys, CM Stadler, PF AF Reidys, CM Stadler, PF TI Neutrality in fitness landscapes SO APPLIED MATHEMATICS AND COMPUTATION LA English DT Article DE random landscapes; ruggedness; neutrality; combinatorial optimization ID GRAPH-BIPARTITIONING PROBLEM; TRAVELING-SALESMAN PROBLEM; RNA SECONDARY STRUCTURES; SEQUENCE STRUCTURE MAPS; NP-COMPLETE PROBLEMS; COMBINATORIAL OPTIMIZATION; EXHAUSTIVE ENUMERATION; STATISTICAL VARIABLES; PRINCIPAL COMPONENTS; LOCAL SEARCH AB The interplay of ruggedness and neutrality in fitness landscapes plays an important role in explaining the dynamics of evolutionary adaptation. While various measures of ruggedness (correlation functions, adaptive walks, or the density of local optima) are reasonably well understood, and models for constructing landscapes with a desired degree of ruggedness are readily available, very little is known about neutrality. We introduce the notion of additive random landscapes as a framework for tuning both neutrality and ruggedness at once, and we develop a formalism that allows the explicit computation of the most salient parameters that are associated with neutrality in landscapes of this type. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Los Alamos Natl Lab, TSA DOSA, Los Alamos, NM 87545 USA. Univ Vienna, Inst Theoret Chem, A-1090 Vienna, Austria. RP Reidys, CM (reprint author), Los Alamos Natl Lab, TSA DOSA, Mailstop TA-0,SM-1237,MS M997, Los Alamos, NM 87545 USA. EM redys@lanl.gov; stadler@santafe.edu RI Stadler, Peter F./L-7857-2015 OI Stadler, Peter F./0000-0002-5016-5191 NR 60 TC 39 Z9 40 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0096-3003 EI 1873-5649 J9 APPL MATH COMPUT JI Appl. Math. Comput. PD JAN 25 PY 2001 VL 117 IS 2-3 BP 321 EP 350 DI 10.1016/S0096-3003(99)00166-6 PG 30 WC Mathematics, Applied SC Mathematics GA 391JC UT WOS:000166352000016 ER PT J AU Chen, KD Iglesia, E Bell, AT AF Chen, KD Iglesia, E Bell, AT TI Isotopic tracer studies of reaction pathways for propane oxidative dehydrogenation on molybdenum oxide catalysts SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID VANADIUM-OXIDE; SELECTIVE OXIDATION; ALKANE REACTIONS; REACTION NETWORK; KINETICS; OXYDEHYDROGENATION; H-ZSM5; MOLYBDATE; EXCHANGE; OXYGEN AB Kinetic analysis and isotopic tracer studies were used to identify the elementary steps and their reversibilty in the oxidative dehydrogenation of propane over ZrO2-supported MoOx catalysts. Competitive reactions of C3H6 and (CH3CH2CH3)-C-13 showed that propene is the most abundant primary product, and that CO and CO2 are formed via either secondary combustion of propene, or by direct combustion of propane. A mixture of C3H8 and C3D8 undergoes oxidative dehydrogenation without forming C3H8-xDx mixed isotopomers, suggesting that steps involving C-H bond activation are irreversible. Normal kinetic isotopic effects (k(C-H)/k(C-D)) were measured for propane dehydrogenation (2.3), propane combustion (1.6) and propene combustion (2.1). These data indicate that the kinetically relevant steps in propane dehydrogenation and propene combustion involve the dissociation of C-H bonds in the respective reactant. H-D exchange occurs readily between C3H6 and D2O or C3D6 and H2O, suggesting that OH recombination steps are reversible and quasi-equilibrated. Reactions of O-18(2)/C3H8 on supported (MoOx)-O-16 species lead to the preferential initial appearance of lattice O-16 atoms in H2O, CO, and CO2, indicating that lattice oxygen is required for C-H bond activation and for the ultimate oxidation of the adsorbed products of this reaction. (OO)-O-18-O-16 was not detected during reactions of C3H8-O-18(2)-O-16(2) mixtures, consistent with irreversible O-2 dissociation steps. These isotopic tracer results are consistent with a Mars-van Krevelen redox mechanism in which two lattice oxygens participate in the irreversible activation of C-H bond in propane. The resulting alkyl species desorb as propene, and the remaining O-H group recombines with neighboring OH groups to form water and reduced Mo centers. The reduced Mo centers finally reoxidize by irreversible dissociative chemisorption of Oz. The proposed reaction mechanism leads to a complex kinetic rate expression that accurately describes the observed dependences on the partial pressure of propane, oxygen, and water. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Iglesia, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RI Iglesia, Enrique/D-9551-2017; OI Iglesia, Enrique/0000-0003-4109-1001; Bell, Alexis/0000-0002-5738-4645 NR 29 TC 57 Z9 58 U1 4 U2 19 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 25 PY 2001 VL 105 IS 3 BP 646 EP 653 DI 10.1021/jp002100x PG 8 WC Chemistry, Physical SC Chemistry GA 402RD UT WOS:000167001200007 ER PT J AU Baldelli, S Mailhot, G Ross, P Shen, YR Somarjai, GA AF Baldelli, S Mailhot, G Ross, P Shen, YR Somarjai, GA TI Potential dependent orientation of acetonitrile on platinum (111) electrode surface studied by sum frequency generation SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ENHANCED RAMAN-SCATTERING; VIBRATIONAL SPECTROSCOPY; INFRARED-SPECTROSCOPY; PHASE MEASUREMENT; DOUBLE-LAYER; INTERFACE; WATER; SYMMETRY; MONOLAYER; MOLECULES AB Sum frequency generation, SFG, vibrational spectroscopy is used to investigate the orientation of acetonitrile (CH3CN) at the Pt(lll) electrode. Acetonitrile is studied as a function of water concentration and electrode potential to determine how these factors affect the adsorbate structure at the interface. The SFG results indicate acetonitrile orients in response to the electrode potential with the C-C bond, C-3 symmetry axis, perpendicular to the surface. The orientation is predominately with the CH3 group toward the metal between 200 and 600 mV and with the CN group toward the metal above 800 mV, (vs NHE, normal hydrogen electrode). The orientation is reversible between 0 and 1400 mV. Addition of water, >0.05x, disrupts the orientation of acetonitrile at the interface. The alignment of acetonitrile along the surface normal is in response to the surface charge at the electrode. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Phys, Div Mat Sci, Berkeley, CA 94720 USA. Univ Blaise Pascal, CNRS, UMR 6505, Lab Photochim, Aubiere, France. RP Somarjai, GA (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 38 TC 38 Z9 39 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 JAN 25 PY 2001 VL 105 IS 3 BP 654 EP 662 DI 10.1021/jp002546d PG 9 WC Chemistry, Physical SC Chemistry GA 402RD UT WOS:000167001200008 ER PT J AU McSween, HY Grove, TL Lentz, RCF Dann, JC Holzheid, AH Riciputi, LR Ryan, JG AF McSween, HY Grove, TL Lentz, RCF Dann, JC Holzheid, AH Riciputi, LR Ryan, JG TI Geochemical evidence for magmatic water within Mars from pyroxenes in the Shergotty meteorite SO NATURE LA English DT Article ID SNC METEORITES; MANTLE; H2O; CONSTRAINTS; SUBDUCTION; ERUPTION; LITHIUM; BORON; MODEL AB Observations of martian surface morphology have been used to argue that an ancient ocean once existed on Mars(1). It has been thought that significant quantities of such water could have been supplied to the martian surface through volcanic outgassing, but this suggestion is contradicted by the low magmatic water content that is generally inferred from chemical analyses of igneous martian meteorites(2). Here, however, we report the distributions of trace elements within pyroxenes of the Shergotty meteorite-a basalt body ejected 175 million years ago from Mars(3) - as well as hydrous and anhydrous crystallization experiments that, together, imply that water contents of pre-eruptive magma on Mars could have been up to 1.8%. We found that in the Shergotty meteorite, the inner cores of pyroxene minerals (which formed at depth in the martian crust) are enriched in soluble trace elements when compared to the outer rims (which crystallized on or near to the martian surface). This implies that water was present in pyroxenes at depth but was largely lost as pyroxenes were carried to the surface during magma ascent. We conclude that ascending magmas possibly delivered significant quantities of water to the martian surface in recent times, reconciling geologic and petrologic constraints on the outgassing history of Mars. C1 Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ S Florida, Dept Geol, Tampa, FL 33620 USA. RP Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. EM mcsween@utk.edu RI Grove, Timothy/M-9638-2013 OI Grove, Timothy/0000-0003-0628-1969 NR 30 TC 131 Z9 132 U1 6 U2 21 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 EI 1476-4687 J9 NATURE JI Nature PD JAN 25 PY 2001 VL 409 IS 6819 BP 487 EP 490 DI 10.1038/35054011 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 395FW UT WOS:000166570500040 PM 11206539 ER PT J AU Simpson, ML Sayler, GS Patterson, G Nivens, DE Bolton, EK Rochelle, JM Arnott, JC Applegate, BM Ripp, S Guillorn, MA AF Simpson, ML Sayler, GS Patterson, G Nivens, DE Bolton, EK Rochelle, JM Arnott, JC Applegate, BM Ripp, S Guillorn, MA TI An integrated CMOS microluminometer for low-level luminescence sensing in the bioluminescent bioreporter integrated circuit SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article DE CMOS microluminometer; bioluminescence; luminometry; biosensors; whole-cell biosensors ID CATABOLIC REPORTER BACTERIUM; ULTRASENSITIVE CHEMILUMINESCENT; SALICYLATE BIOAVAILABILITY; NAPHTHALENE; PHOTODIODES; TECHNOLOGY; ASSAY AB We report an integrated CMOS microluminometer for the detection of low-level bioluminescence in whole cell biosensing applications. This microluminometer is the microelectronic portion of the bioluminescent bioreporter integrated circuit (BBIC). This device uses the n-well/p-substrate junction of a standard bull: CMOS IC process to form the integrated photodetector. This photodetector uses a distributed electrode configuration that minimizes detector noise. Signal processing is accomplished with a current-to-frequency converter circuit that forms the causal portion of the matched filter far de luminescence in wide-band white noise. Measurements show that luminescence can be detected from as few as 4 x 10(5) cells/ml. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37996 USA. RP Simpson, ML (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Ripp, Steven/B-2305-2008; Simpson, Michael/A-8410-2011 OI Ripp, Steven/0000-0002-6836-1764; Simpson, Michael/0000-0002-3933-3457 NR 31 TC 45 Z9 46 U1 1 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD JAN 25 PY 2001 VL 72 IS 2 BP 134 EP 140 DI 10.1016/S0925-4005(00)00641-9 PG 7 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 397HW UT WOS:000166688100006 PM 12192685 ER PT J AU Grant, SA Bettencourt, K Krulevitch, P Hamilton, J Glass, R AF Grant, SA Bettencourt, K Krulevitch, P Hamilton, J Glass, R TI In vitro and in vivo measurements of fiber optic and electrochemical sensors to monitor brain tissue pH SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article DE sol-gel method; optoelectronics; stroke; brain injury; iridium oxide ID OXYGEN; BIOSENSOR; STROKE; INJURY AB We report herein the development of fiber optic and electrochemical pH sensors that could become part of an arsenal to quickly and aggressively treat people undergoing a stroke as well as people who have suffered traumatic brain injury. The fiber optic pH sensor design consists of the immobilization of a pH sensitive dye, seminaphthorhodamine-1 carboxylate (SNARF-1C) within a silica sol-gel matrix. A miniature optoelectronics package was developed to acquire data from the fiber optic sensor. The electrochemical sensor consists of a thin film multilayer coating sputtered on a kapton substrate. The sensors were tested in vitro and in vivo. For both sensors, the in vitro results show linear and reproducible responses in human blood in the pH range 6.8-8.0. The results of the in vivo studies which were performed in Spraque-Dawley rats indicate that both the fiber optic and electrochemical sensors monitor pH with very little drift. It was concluded that both types of sensors would be useful in tracking brain tissue pH. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RP Grant, SA (reprint author), Michigan Technol Univ, Ctr Biomed Engn, 1400 Townsend Dr, Houghton, MI 49931 USA. NR 20 TC 62 Z9 62 U1 1 U2 26 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD JAN 25 PY 2001 VL 72 IS 2 BP 174 EP 179 DI 10.1016/S0925-4005(00)00650-X PG 6 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 397HW UT WOS:000166688100011 ER PT J AU Fletcher, M Levy, ME Griffin, DD AF Fletcher, M Levy, ME Griffin, DD TI Foodborne outbreak of group A rotavirus gastroenteritis among college students - District of Columbia, March-April 2000 (Reprinted from MMWR, vol 49, pg 1131-1133, 2000) SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Reprint C1 Dept Hlth, Bur Epidemiol & Dis Control, Washington, DC 20037 USA. Oak Ridge Associated Univ, US DOE, Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. CDC, Viral Gastroenteritis Sect, Resp & Enterovirus Branch, Div Viral & Rickettsial Dis,Natl Ctr Infect Dis, Atlanta, GA 30333 USA. RP Fletcher, M (reprint author), Dept Hlth, Bur Epidemiol & Dis Control, Washington, DC 20037 USA. NR 1 TC 10 Z9 10 U1 1 U2 3 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0098-7484 J9 JAMA-J AM MED ASSOC JI JAMA-J. Am. Med. Assoc. PD JAN 24 PY 2001 VL 285 IS 4 BP 405 EP 406 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 394CG UT WOS:000166506000013 ER PT J AU Glaser, T Rose, K Shadle, SE Hedman, B Hodgson, KO Solomon, EI AF Glaser, T Rose, K Shadle, SE Hedman, B Hodgson, KO Solomon, EI TI SK-edge X-ray absorption studies of tetranuclear iron-sulfur clusters: mu-sulfide bonding and its contribution to electron delocalization SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID LIGAND K-EDGE; DENSITY-FUNCTIONAL CALCULATIONS; TRANSITION-METAL DIMERS; 2-FE FERREDOXIN MODELS; MIXED-VALENCE DIMERS; REDOX POTENTIALS; ACTIVE-SITES; COMPLEXES; COVALENCY; SPECTROSCOPY AB X-ray absorption spectroscopy (XAS) at the sulfur (similar to 2470 eV) and chlorine (similar to 2822 eV) K-edges has been applied to a series of 4Fe-4S model complexes. These are compared to 2Fe-2S model complexes to obtain insight into the localized ground state in the mixed-valence dimer versus the delocalized ground state in the mixed-valence tetramer. The preedges of hypothetical delocalized mixed-valence dimers [Fe2S2](+) are estimated using trends from experimental data and density functional calculations, for comparison to the delocalized mixed-valence tetramer [Fe4S4](2+). The differences between these two mixed-valence sites are due to the change of the sulfide-bridging mode from mu (2) to mu (3). The terminal chloride and thiolate ligands are used as spectator ligands for the electron density of the iron center. From the intensity of the preedge, the covalency of the terminal ligands is found to increase in the tetramer as compared to the dimer. This is associated with a higher effective nuclear charge on the iron in the tetramer (derived from the energies of the preedge). The mu (3)-bridging sulfide in the tetramer has a reduced covalency per bond (39%) as compared to the mu (2)-bridging sulfide in the dimer (51%). A simple perturbation model is used to derive a quadratic dependence of the superexchange coupling constant J on the covalency of the metal ions with the bridging ligands. This relationship is used to estimate the superexchange contribution in the tetramer (J = -156 cm(-1)) as compared to the mixed-valence dimer (J = -360 cm-l). These results, combined with estimates for the double exchange and the vibronic coupling contributions of the dimer sub-site of the tetramer, lead to a delocalized S-t = 9/2 spin ground state for the mixed-valence dimer in the tetramer. Thus, the decrease in the covalency, hence the superexchange pathway associated with changing the bridging mode of the sulfides from mu (2) to mu (3) On going from the dimer to the tetramer, significantly contributes to the delocalization of the excess electron over the dimer sub-site in the tetramer. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Hedman, B (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94305 USA. RI Glaser, Thorsten/H-5187-2013 OI Glaser, Thorsten/0000-0003-2056-7701 FU NCRR NIH HHS [RR-01209] NR 71 TC 76 Z9 76 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 24 PY 2001 VL 123 IS 3 BP 442 EP 454 DI 10.1021/ja002183v PG 13 WC Chemistry, Multidisciplinary SC Chemistry GA 397LW UT WOS:000166698000011 PM 11456546 ER PT J AU Peterson, TH Golden, JT Bergman, RG AF Peterson, TH Golden, JT Bergman, RG TI Evidence for the intervention of different C-H activating intermediates in the irradiation of (eta(5)-C5Me5)(PMe3)IrH2 and the reaction of (eta(5)-C5Me5)(PMe3)Ir(H) (Cl) with strong base. Detection and spectroscopic characterization of (eta(5)-C5Me5) (PMe3)Ir(Li)(Cl), an intermediate in the dehydrohalogenation reaction SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID COBALT-CATALYZED HYDROFORMYLATION; HYDROGEN-BOND ACTIVATION; RESOLVED IR SPECTROSCOPY; LIQUID RARE-GASES; OXIDATIVE ADDITION; ALKANE COMPLEX; REDUCTIVE ELIMINATION; IRIDIUM COMPLEXES; MATRIX-ISOLATION; RHODIUM AB Reaction of (eta (5)-CsMe5)(PMe3)Ir(H)(X) (X = Cl, Br) with tert-butyllithium in hydrocarbon solvent results in dehydrohalogenation of the iridium center and subsequent C-H bond activation of solvent to give (eta (5)-C5Me5)(PMe3)Ir(R)(H) (R = Ph, cyclohexyl, cyclooctyl). Low-temperature H-1, P-31, and Li-7 NMR studies indicate that the dehydrohalogenation reaction occurs via the formation of the intermediate (eta (5)-C5Me5)(PMe3)Ir(Li)(X). Competition experiments involving C-H bond activation in benzene-cyclohexane-cyclooctane mixtures have allowed for the determination of a relative intermolecular selectivity scale for these substrates. The selectivities (reported on a per hydrogen basis) for benzene, cyclooctane, and cyclohexane C-H bond activation were found to be 4.98:0.74:1, respectively, and are significantly different from those obtained via photoinduced dihydrogen elimination from (eta (5)-C5Me5)(PMe3)IrH2. Further, when Bronsted bases other than tert-butyllithium were employed, the intermolecular selectivities in the base-promoted dehydrohalogenation reaction were found to be dependent on the alkali metal, but not the counteranion, of the base, with benzene/cycloalkane selectivity increasing in the order K > Na > Li. These results provide strong evidence that the selectivity-determining steps in the C-H bond activations by dehydrohalogenation of (eta (5)-C5Me5)(PMe3)Ir(H)(X) and the photoinduced dihydrogen elimination in (eta (5)-C5Me5)(PMe3)IrH2 involve different reactive intermediates. In the base-induced reaction, we postulate that the eliminated salt remains coordinated to the iridium, primarily through the alkali metal, in the C-H activation transition state. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat & Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. RP Bergman, RG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat & Chem Sci, Berkeley, CA 94720 USA. NR 38 TC 38 Z9 38 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 24 PY 2001 VL 123 IS 3 BP 455 EP 462 DI 10.1021/ja0024993 PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA 397LW UT WOS:000166698000012 ER PT J AU Waggoner, TA Last, JA Kotula, PG Sasaki, DY AF Waggoner, TA Last, JA Kotula, PG Sasaki, DY TI Self-assembled columns of stacked lipid bilayers mediated by metal ion recognition SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID OPTICAL-DETECTION; COMPLEXES; VESICLES; PHASE C1 Sandia Natl Labs, Biomol Mat & Interfaces Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Mat Characterizat Dept, Albuquerque, NM 87185 USA. RP Sasaki, DY (reprint author), Sandia Natl Labs, Biomol Mat & Interfaces Dept, MS 1413, Albuquerque, NM 87185 USA. RI Kotula, Paul/A-7657-2011 OI Kotula, Paul/0000-0002-7521-2759 NR 12 TC 41 Z9 41 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 24 PY 2001 VL 123 IS 3 BP 496 EP 497 DI 10.1021/ja002754j PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 397LW UT WOS:000166698000018 PM 11456553 ER PT J AU Heaton, DN George, GN Garrison, G Winge, DR AF Heaton, DN George, GN Garrison, G Winge, DR TI The mitochondrial copper metallochaperone Cox17 exists as an oligomeric, polycopper complex SO BIOCHEMISTRY LA English DT Article ID CYTOCHROME-C-OXIDASE; SACCHAROMYCES-CEREVISIAE; THIOLATE COMPLEXES; HEME-A; YEAST; PROTEIN; COORDINATION; METABOLISM; OXIDATION; PRODUCT AB COX 17 is the candidate copper metallochaperone fbr delivery of copper ions to the mitochondrion for assembly of cytochrome c oxidase. Cox 17 purified as a recombinant molecule lacking any purification tag binds three Cu(I) ions per monomer in a plolycopper cluster as shown by X-ray absorption spectroscopy. The CuCox17 complex exists in a dimer/tetramer equilibrium with a 20 muM k(d). The spectroscopic data do not discern whether the dimeric complex forms a single hexanuclear Cu(I) cluster or two separate trinuclear Cu(I) clusters. The Cu(I) cluster(s) exhibit(s) predominantly trigonal Cu(I) coordination. The cluster(s) in CoX17 resemble(s) the polycopper clusters in Ace1 and the Cup1 metallothionein in being pH-stable and luminescent. The physical properties of the CuCox17 complex purified as an untagged molecule differ from those reported previously for a GST-Cox17 fusion protein. The CuCox17 cluster is distinct from the polycopper cluster in Cup1 in being labile to ligand exchange. CuCox17 localized within the intermitochondrial membrane space appears to be predominantly tetrameric, whereas the cytosolic CuCox17 is primarily a dimeric species. Cys --> Ser substitutions at Cys23, Cys24, or Cys26 abolish the CoX17 function and prevent tetramerization, although Cu(I) binding is largely unaffected. Thus, the oligomeric state of Cox17 may be important to its physiological function. C1 Univ Utah, Hlth Sci Ctr, Salt Lake City, UT 84132 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Winge, DR (reprint author), Univ Utah, Hlth Sci Ctr, 50 N Med Dr, Salt Lake City, UT 84132 USA. RI Winge, Dennis/G-3611-2010; George, Graham/E-3290-2013 FU NCI NIH HHS [5P30-CA 42014]; NIEHS NIH HHS [ES 03817] NR 33 TC 82 Z9 85 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JAN 23 PY 2001 VL 40 IS 3 BP 743 EP 751 DI 10.1021/bi002315x PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 393YJ UT WOS:000166497000016 PM 11170391 ER PT J AU Heatherly, L George, EP AF Heatherly, L George, EP TI Grain-boundary segregation of impurities in iridium and effects on mechanical properties SO ACTA MATERIALIA LA English DT Article DE iridium; grain boundaries; segregation; mechanical properties ID BORON-DOPED NI3AL; FRACTURE-BEHAVIOR; TEMPERATURE DUCTILITY; ALLOYS; ENVIRONMENT; ADDITIONS AB Impurity effects were investigated in an Ir alloy of nominal composition Ir-0.3 W-0.006 Th-0.005 Al double dagger. The impurities that were added included Fe, Ni, Cr, Al, and Si, at levels ranging from 50 to 5000 ppm. Of the elements investigated (impurities as well as alloying additions), only Si and Th were found to segregate to the grain boundaries. In alloys doped with low levels of Si (<200 ppm), both Si and Th segregated to the grant boundaries. In addition, Th-containing precipitates were identified in these alloys, but not Si-containing precipitates. When added at higher bulk levels, Si displaced (beneficial) Th from the boundaries. This caused the segregated Th at the boundaries to decrease (to practically zero) when the amount of grain-boundary Si increased (to its saturation level). Silicon also reacted with Th to form Ir-Th-Si precipitates and promoted the formation of a low-melting eutectic on the grain boundaries of the highest Si alloys. As for the other elements, not only did they not segregate to the grain boundaries, but they also did not affect Th segregation. Together, these results explain why Fe, Ni, Cr, Al (and Si at low levels) do not embrittle iridium, whereas Si at high levels causes severe embrittlement. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Heatherly, L (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI George, Easo/L-5434-2014 NR 30 TC 17 Z9 21 U1 1 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JAN 22 PY 2001 VL 49 IS 2 BP 289 EP 298 DI 10.1016/S1359-6454(00)00313-X PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 397EY UT WOS:000166681400009 ER PT J AU Kwok, DTK Zhang, T Chu, PK Bilek, MMM Vizir, A Brown, IG AF Kwok, DTK Zhang, T Chu, PK Bilek, MMM Vizir, A Brown, IG TI Experimental investigation of electron oscillation inside the filter of a vacuum arc plasma source SO APPLIED PHYSICS LETTERS LA English DT Article ID CATHODIC ARC; DEPOSITION; TRANSPORT; PRINCIPLES; COATINGS; FILMS; DUCT AB We report here experimental evidence of electron oscillation within the toroidal-section magnetic duct of a filtered vacuum arc plasma source. Our results clearly demonstrate that electrons can oscillate inside the duct under the combined effects of the electric and magnetic fields. In another experiment, we observe that, under the influence of the electron motion, the trajectories of the plasma ions are more or less unchanged except in the intensity when the Bilek plate is biased. Finally, our time-of-flight experiments show that the effects due to collisional scattering between plasma ions and oscillating electrons are masked by those associated with the metal plasma flow through the duct, and collisional scattering does not give rise to an increase of the mean charge state of the plasma ions. We conclude that the application of a bias voltage to the duct not only perturbs the ions but also influences the plasma electrons. Our results demonstrate that electrons at the central axis are one of the major reasons leading to improved plasma transport through the duct. (C) 2001 American Institute of Physics. C1 City Univ Hong Kong, Dept Phys & Mat Sci, Kowloon, Hong Kong, Peoples R China. Univ Cambridge, Dept Engn, Cambridge CB2 1PZ, England. Russian Acad Sci, Inst High Current Elect, Tomsk 634055, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Chu, PK (reprint author), City Univ Hong Kong, Dept Phys & Mat Sci, 83 Tat Chee Ave, Kowloon, Hong Kong, Peoples R China. EM paul.chu@cityu.edu.hk RI Chu, Paul/B-5923-2013; Vizir, Alexey/R-2139-2016 OI Chu, Paul/0000-0002-5581-4883; Vizir, Alexey/0000-0002-9563-8650 NR 17 TC 9 Z9 9 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 22 PY 2001 VL 78 IS 4 BP 422 EP 424 DI 10.1063/1.1342779 PG 3 WC Physics, Applied SC Physics GA 393NV UT WOS:000166477300011 ER PT J AU Park, BH Peterson, EJ Jia, QX Lee, J Zeng, X Si, W Xi, XX AF Park, BH Peterson, EJ Jia, QX Lee, J Zeng, X Si, W Xi, XX TI Effects of very thin strain layers on dielectric properties of epitaxial Ba0.6Sr0.4TiO3 films SO APPLIED PHYSICS LETTERS LA English DT Article AB We have epitaxially grown Ba0.6Sr0.4TiO3 (BST-0.4) thin films on MgO(001) substrates. By inserting a very thin Ba1-xSrxTiO3 (x=0.1-0.7) interlayer between the MgO substrate and the main layer of BST-0.4, we are able to manipulate the degree of the stress in BST-0.4 films. We have controlled the stress states, i.e., the lattice distortion ratio (D=in-plane lattice constant/out-of-plane lattice constant) of the BST-0.4 films by varying the chemical composition of the interlayers. We have found that small variations of D value can result in significantly large changes of dielectric properties. A BST-0.4 film under small tensile stress, which has a D value of 1.0023, shows the largest dielectric permittivity and tunability. (C) 2001 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Sungkyunkwan Univ, Dept Mat Engn, Suwon 440746, South Korea. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. RP Park, BH (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM bhpark@lanl.gov; qxjia@lanl.gov RI Park, Bae Ho/D-4840-2011; Jia, Q. X./C-5194-2008 NR 14 TC 155 Z9 159 U1 3 U2 26 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 22 PY 2001 VL 78 IS 4 BP 533 EP 535 DI 10.1063/1.1340863 PG 3 WC Physics, Applied SC Physics GA 393NV UT WOS:000166477300049 ER PT J AU Ahrenkiel, RK Johnston, SW Keyes, BM Friedman, DJ Vernon, SM AF Ahrenkiel, RK Johnston, SW Keyes, BM Friedman, DJ Vernon, SM TI Transport properties of GaAs1-xNx thin films grown by metalorganic chemical vapor deposition (vol 77, pg 3794, 2000) SO APPLIED PHYSICS LETTERS LA English DT Correction C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Spire Corp, Bedford, MA 01730 USA. RP Ahrenkiel, RK (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 1 TC 0 Z9 0 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 22 PY 2001 VL 78 IS 4 BP 559 EP 559 DI 10.1063/1.1346587 PG 1 WC Physics, Applied SC Physics GA 393NV UT WOS:000166477300058 ER PT J AU Bluhm, BK North, SW Russell, DH AF Bluhm, BK North, SW Russell, DH TI Separation of spin-orbit coupled metastable states of Kr+ and Xe+ by ion mobility SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TRANSITION-METAL IONS; RADIATIVE LIFETIMES; ENERGY; CHROMATOGRAPHY; REACTIVITY; CURVES; HELIUM; NEON AB The spin-orbit coupled ground states of Kr+. and Xe+. (RG P-2(1/2) and RG P-2(3/2) RG=rare gas) are separated on the basis of ion mobility. Ion mobility separation of Kr+. and Xe+. is based on different interaction potentials of the P-2(1/2) and P-2(3/2), ionic states with helium. The ion mobility instrument used for these studies is a novel instrument based on a Fourier-transform ion cyclotron resonance mass spectrometer. The assignment of the spin-orbit coupled states of Xe+. is consistent with results from charge exchange ion-molecule reactions of Xe+. with N2O. (C) 2001 American Institute of Physics. C1 Texas A&M Univ, Dept Chem, Lab Biol Mass Spectrometry, College Stn, TX 77842 USA. RP Bluhm, BK (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS J585, Los Alamos, NM 87545 USA. RI North, Simon/G-5054-2012; Russell, David/C-3618-2015 OI North, Simon/0000-0002-0795-796X; Russell, David/0000-0003-0830-3914 NR 28 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2001 VL 114 IS 4 BP 1709 EP 1715 DI 10.1063/1.1334896 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 396QD UT WOS:000166647300030 ER PT J AU Mugele, F Salmeron, M AF Mugele, F Salmeron, M TI Frictional properties of thin chain alcohol films SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID STICK-SLIP FRICTION; SIMPLE LIQUIDS; PHASE-TRANSITIONS; KINETIC FRICTION; SHEAR; LAYERS; MECHANISMS; APPARATUS; SURFACES; CONTACT AB We used the surface forces apparatus (SFA) Co measure the viscosity and friction of confined films of octanol and undecanol as a function of film thickness. In contrast to structurally similar alkanes, the alcohols retain their bulk-like lubrication properties down to a thickness of only one (bi)layer. Only the self-assembled monolayers of alcohol molecules that form spontaneously on each mica surface display solid-like stick-slip motion upon shearing. During stick-slip motion, microscopic creep is found to precede macroscopic slip events at high loads. Apart from this creep process, we find a well-defined critical shear stress during stick-slip motion, which decreases weakly with increasing sliding speed. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Ulm, Abt Angew Phys, D-89069 Ulm, Germany. RP Salmeron, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Mugele, Frieder/A-5225-2017 OI Mugele, Frieder/0000-0003-3824-3617 NR 27 TC 21 Z9 21 U1 0 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2001 VL 114 IS 4 BP 1831 EP 1836 DI 10.1063/1.1333756 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 396QD UT WOS:000166647300046 ER PT J AU McCabe, C Cui, ST Cummings, PT Gordon, PA Saeger, RB AF McCabe, C Cui, ST Cummings, PT Gordon, PA Saeger, RB TI Examining the rheology of 9-octylheptadecane to giga-pascal pressures SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID NONEQUILIBRIUM MOLECULAR-DYNAMICS; BRANCHED ALKANES; COMPUTER-SIMULATIONS; N-ALKANES; DECANE; HEXADECANE; BEHAVIOR; EICOSANE AB The properties of alkanes in the C-20-C-40 mass range are of fundamental importance in industrial applications as they are important constituents of synthetic lubricant base stocks. In an extension to earlier work on alkanes in the C-20-C-40 carbon number range we present the results of molecular simulations for 9-octylheptadecane, a starlike isomer of C-25 Both equilibrium (EMD) and nonequilibrium molecular dynamics (NEMD) simulations have been performed under ambient state conditions and to pressures in the gigapascal range. The EMD simulations focus on calculations of the rotational relaxation times, while the NEMD simulations reveal the dependence of the viscosity on strain rate. Additionally, we calculate the viscosity number and pressure-viscosity coefficient for 9-octylheptadecane and compare the results with those obtained experimentally. (C) 2001 American Institute of Physics. C1 Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. ExxonMobil Res & Engn Co, Corp Strateg Res Ctr, Annandale, NJ 08801 USA. RP McCabe, C (reprint author), Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. RI McCabe, Clare/I-8017-2012; Cummings, Peter/B-8762-2013 OI McCabe, Clare/0000-0002-8552-9135; Cummings, Peter/0000-0002-9766-2216 NR 23 TC 31 Z9 32 U1 1 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2001 VL 114 IS 4 BP 1887 EP 1891 DI 10.1063/1.1334676 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 396QD UT WOS:000166647300054 ER PT J AU Sheldon, RI Rinehart, GH Krishnan, S Nordine, PC AF Sheldon, RI Rinehart, GH Krishnan, S Nordine, PC TI The optical properties of liquid cerium at 632.8 nm SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article DE cerium; optical properties ID TEMPERATURE; NICKEL AB The normal, spectral emissivity, epsilon (lambda)(T), and optical constants, n and k, of liquid cerium were measured at 632.8 nm over a temperature range of 1700-2130 K using rotating analyzer ellipsometry. The cerium was electromagnetically levitated to prevent contamination of the liquid metal by contact with a container and purified by vaporization of volatile oxides at high temperature. The emissivity at 0.9 mum and 1900 K was determined from the brightness temperature. The solubility of oxygen in liquid cerium at 1786 K was estimated and the effect of oxygen on the optical properties was demonstrated. Using available thermodynamic data and assumptions of ideal solution behavior, the volatilization of oxygen and nitrogen impurities is discussed. At 1786 K, the solubility of oxygen in liquid cerium is between 3 and 7 atom percent. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. Containerless Res Inc, Evanston, IL 60201 USA. RP Sheldon, RI (reprint author), Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, POB 1663, Los Alamos, NM 87545 USA. NR 25 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5107 J9 MAT SCI ENG B-SOLID JI Mater. Sci. Eng. B-Solid State Mater. Adv. Technol. PD JAN 22 PY 2001 VL 79 IS 2 BP 113 EP 122 DI 10.1016/S0921-5107(00)00553-5 PG 10 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 403FN UT WOS:000167032000003 ER PT J AU He, XY Merz, G Chu, CH Lin, DW Yang, YZ Mehta, P Schulz, H Yang, SY AF He, XY Merz, G Chu, CH Lin, DW Yang, YZ Mehta, P Schulz, H Yang, SY TI Molecular cloning, modeling, and localization of rat type 10 17 beta-hydroxysteroid dehydrogenase SO MOLECULAR AND CELLULAR ENDOCRINOLOGY LA English DT Article; Proceedings Paper CT Conference on Recent Progress in Research on 17 Beta-Hydroxysteroid Dehydrogenases: Impact on Medicine CY APR 04-08, 2000 CL ELMAU CASTLE, GERMANY SP Volkswagen Stift, GSF Forsch Szentrum, Umwelt & Gesundheit DE sex steroids; metabolism; mitochondria; rat brain; mouse brain ID COENZYME-A DEHYDROGENASE; RECEPTOR-ASSOCIATED PROTEIN; EXPRESSION CLONING; 3-HYDROXYACYL-COA DEHYDROGENASE; ESCHERICHIA-COLI; HUMAN PROSTATE; MITOCHONDRIAL; MOUSE; BETA; MEMBRANE AB Rat and mouse complementary DNAs of type 10 17 beta -hydroxysteroid dehydrogenase were cloned and sequenced. The mouse cDNA clone's sequence corrected the previously published nucleotide and amino acid sequence of mouse endoplasmic reticulum-associated beta -amyloid-binding protein. A subunit of the rat enzyme consists of 261 amino acid residues with a calculated molecular mass of 27 250 Da. Compared with its human counterpart, rat 17 beta HSD type 10 shows 88% identity. Mouse 17 beta HSD type 10 is composed of 261 amino acid residues with a calculated molecular mass of 27 274 Da. There is 95%, identity between the two rodent enzymes. A stereostructure model of rat 17 beta HSD type 10 was constructed based on its amino acid sequence. Similar to human type 10 17 beta HSD, the rodent enzymes also displayed relatively higher 3 alpha HSD activity than 17 beta HSD activity. Intracellular localization of rat 17 beta HSD type 10 has been determined by subcellular fractionation and confocal microscopy studies. The results unequivocally establish that this is a nuclear gene-encoded mitochondrial enzyme, and that this 17 beta HSD is not associated with the endoplasmic reticulum. The unique location distinguishes type 10 From other types of 17 beta -hydroxysteroid dehydrogenases. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved. C1 New York State Inst Basic Res Dev Disabil, Dept Pharmacol, Staten Isl, NY 10314 USA. New York State Inst Basic Res Dev Disabil, Dept Pathol Neurobiol, Staten Isl, NY 10314 USA. CUNY City Coll, Dept Chem, New York, NY 10031 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. New York State Inst Basic Res Dev Disabil, Dept Immunol, Staten Isl, NY 10314 USA. RP New York State Inst Basic Res Dev Disabil, Dept Pharmacol, 1050 Forest Hill Rd, Staten Isl, NY 10314 USA. EM yang_songyu@yahoo.com FU NHLBI NIH HHS [HL30847]; NIA NIH HHS [AG04420] NR 46 TC 16 Z9 17 U1 1 U2 2 PU ELSEVIER IRELAND LTD PI CLARE PA ELSEVIER HOUSE, BROOKVALE PLAZA, EAST PARK SHANNON, CO, CLARE, 00000, IRELAND SN 0303-7207 J9 MOL CELL ENDOCRINOL JI Mol. Cell. Endocrinol. PD JAN 22 PY 2001 VL 171 IS 1-2 BP 89 EP 98 DI 10.1016/S0303-7207(00)00391-9 PG 10 WC Cell Biology; Endocrinology & Metabolism SC Cell Biology; Endocrinology & Metabolism GA 452WZ UT WOS:000169883800014 PM 11165016 ER PT J AU Han, T Kim, YJ Likhoded, A Valencia, G AF Han, T Kim, YJ Likhoded, A Valencia, G TI Top-quark couplings to TeV resonances at future lepton colliders SO NUCLEAR PHYSICS B LA English DT Article ID ELECTROWEAK SYMMETRY-BREAKING; FERMION MASS GENERATION; STRONGLY INTERACTING WS; GOLD-PLATED MODES; EQUIVALENCE THEOREM; HIGGS-BOSON; STANDARD MODEL; WW SCATTERING; SECTOR; UNITARITY AB We study the processes W-L W-L --> t (t) over bar and W-L Z(L) --> t (b) over bar ((t) over barb) at future lepton colliders as probes of the couplings of the top quark to resonances at the TeV scale. We consider the cases in which the dominant low energy feature of a strongly interacting electroweak symmetry breaking sector is either a scalar or a vector resonance with mass near 1 TeV. We find that future lepton colliders with high energy and high luminosity have great potential to sensitively probe these physics scenarios. In particular, at a 1.5 TeV linear collider with an integrated luminosity of 200 fb(-1), we expect about 120 events for either a scalar or a vector to decay to t (t) over bar, tb. Their leading partial decay widths, which characterize the coupling strengths, can be statistically determined to about 10% level. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Inst High Energy Phys, Protvino, Russia. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Valencia, G (reprint author), Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. NR 65 TC 13 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD JAN 22 PY 2001 VL 593 IS 3 BP 415 EP 437 DI 10.1016/S0550-3213(00)00643-X PG 23 WC Physics, Particles & Fields SC Physics GA 393RL UT WOS:000166483400001 ER PT J AU John, KD Salazar, KV Scott, BL Baker, RT Sattelberger, AP AF John, KD Salazar, KV Scott, BL Baker, RT Sattelberger, AP TI Comparison of the reactivity of M(allyl)(3) (M = Rh, Ir) with donor ligands SO ORGANOMETALLICS LA English DT Article ID RAY CRYSTAL-STRUCTURES; COMPLEXES; RHODIUM AB Reactions of M(allyl)(3) [M = Rh, Ir] with a variety of donor ligands have been investigated. While both complexes are unreactive toward "hard" N- and O-donor ligands, "soft" ligands such as tolylisothiocyanate, tertiary phosphines, CO, and aryl isocyanides are readily added. Whereas ligand additions to Rh(allyl)(3) are often accompanied by reduction of the Rh(III) center, analogous reactions with Ir(allyl)(3) afford stable trivalent products containing sigma -allyl ligands. The molecular structures of several derivatives are presented, including Ir(sigma -allyl)(pi -allyl)(2)(PPh3), Ir(sigma -allyl)(2)(pi -allyl)(PMe3)(2), and Ir(sigma -allyl)(3)(C dropN-2,6-Me2C6H3)(3). C1 Univ Calif Los Alamos Natl Lab, Div Chem, Los Alamos Catalysis Initiat Chem, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM 87545 USA. RP Sattelberger, AP (reprint author), Univ Calif Los Alamos Natl Lab, Div Chem, Los Alamos Catalysis Initiat Chem, POB 1663, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017; OI Scott, Brian/0000-0003-0468-5396; John, Kevin/0000-0002-6181-9330 NR 24 TC 27 Z9 27 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD JAN 22 PY 2001 VL 20 IS 2 BP 296 EP 304 DI 10.1021/om000734k PG 9 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 393XA UT WOS:000166493900011 ER PT J AU Son, DT Stephanov, MA AF Son, DT Stephanov, MA TI QCD at finite isospin density SO PHYSICAL REVIEW LETTERS LA English DT Article ID STRONG COUPLING LIMIT; LATTICE SU(N) QCD; BARYON DENSITY; QUANTUM CHROMODYNAMICS; MASS INEQUALITIES; MATTER; SUPERCONDUCTIVITY; TEMPERATURE; QUARK AB QCD at finite isospin chemical potential mu (l) has no fermion sign problem and can be studied on the lattice. We solve this theory analytically in two limits: at low mu (l), where chiral perturbation theory is applicable, and at asymptotically high mu (l), where perturbative QCD works. At low isospin density the ground state is a pion condensate, whereas at high density it is a Fermi liquid with Cooper pairing. The pairs carry the same quantum numbers as the pion. This leads us to conjecture that the transition from hadron to quark matter is smooth, which passes several tests. Our results imply a nontrivial phase diagram in the space of temperature and chemical potentials of isospin and baryon number. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Brookhaven Natl Lab, RIKEN, Res Ctr, Upton, NY 11973 USA. RP Son, DT (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. NR 37 TC 294 Z9 294 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 22 PY 2001 VL 86 IS 4 BP 592 EP 595 DI 10.1103/PhysRevLett.86.592 PG 4 WC Physics, Multidisciplinary SC Physics GA 394TT UT WOS:000166539900009 PM 11177889 ER PT J AU Lower, J Weigold, E Berakdar, J Mazevet, S AF Lower, J Weigold, E Berakdar, J Mazevet, S TI Magnetic and orbital dichroism in (e, 2e) ionization of sodium SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRON-IMPACT IONIZATION; LITHIUM AB We present the first measurement of (e, 2e) ionization cross sections for a laser oriented atomic target by spin polarized electrons. Cross sections are presented as a function of target orientation and polarization direction of the incident electron beam. This study provides insight into mechanisms by which angular momentum is transferred from the valence electron to the two final-state continuum electrons in both singlet and triplet spin channels, by comparing measurement with distorted wave Born approximation and the dynamically screened three Coulomb wave calculations. C1 Australian Natl Univ, Res Sch Phys Sci & Engn, Atom & Mol Phys Lab, Canberra, ACT 0200, Australia. Max Planck Inst Microstruct Phys, D-06120 Halle, Germany. Univ Calif Los Alamos Natl Lab, T Div, Los Alamos, NM 87545 USA. RP Lower, J (reprint author), Australian Natl Univ, Res Sch Phys Sci & Engn, Atom & Mol Phys Lab, Canberra, ACT 0200, Australia. NR 14 TC 18 Z9 18 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 22 PY 2001 VL 86 IS 4 BP 624 EP 627 DI 10.1103/PhysRevLett.86.624 PG 4 WC Physics, Multidisciplinary SC Physics GA 394TT UT WOS:000166539900017 PM 11177897 ER PT J AU Gruber, L Holder, JP Steiger, J Beck, BR DeWitt, HE Glassman, J McDonald, JW Church, DA Schneider, D AF Gruber, L Holder, JP Steiger, J Beck, BR DeWitt, HE Glassman, J McDonald, JW Church, DA Schneider, D TI Evidence for highly charged ion Coulomb crystallization in multicomponent strongly coupled plasmas SO PHYSICAL REVIEW LETTERS LA English DT Article ID LASER SPECTROSCOPY; TRAP; PHASE; EBIT; BEAM AB Multicomponent non-neutral ion plasmas in a Penning trap consisting of Be+ and highly charged Xe ions, having different mass-to-charge ratios than Be+, are cooled to form strongly coupled plasmas by applying a laser-based collisional cooling scheme. The temperature of the plasma was determined from a Doppler broadened transition in Be+. For the Xe ions, which are centrifugally separated from the Be, the Coulomb coupling parameter was estimated to be approximate to 1000. Molecular dynamics simulations of the ion mixture show ordered structures, indicating crystallization of the Xe. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. RP Gruber, L (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 23 TC 56 Z9 56 U1 0 U2 15 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 22 PY 2001 VL 86 IS 4 BP 636 EP 639 DI 10.1103/PhysRevLett.86.636 PG 4 WC Physics, Multidisciplinary SC Physics GA 394TT UT WOS:000166539900020 PM 11177900 ER PT J AU Thayer, GE Ozolins, V Schmid, AK Bartelt, NC Asta, H Hoyt, JJ Chiang, S Hwang, RQ AF Thayer, GE Ozolins, V Schmid, AK Bartelt, NC Asta, H Hoyt, JJ Chiang, S Hwang, RQ TI Role of stress in thin film alloy thermodynamics: Competition between alloying and dislocation formation SO PHYSICAL REVIEW LETTERS LA English DT Article ID TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; MOLECULAR-DYNAMICS; SURFACE; GROWTH; METALS; SYSTEMS AB Using scanning tunneling microscopy (STM) and first-principles local-spin-dsnsity-approximation calculations to stud; submonolayer films of Co1-cAgc/Ru(0001) alloys, we have discovered a novel phase-separation mechanism. When the Ag concentration c exceeds 0.4, the surface phase separates between a dislocated, pure Ag phase and a pseudomorphically strained Co0.6Ag0.4 surface alloy. We attribute the phase separation to the competition between two stress relief mechanisms: surface alloying and dislocation formation. The agreement between STM measurements and our calculated phase diagram supports this interpretation. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Sandia Natl Labs, Livermore, CA 94551 USA. RI Ozolins, Vidvuds/D-4578-2009 NR 20 TC 47 Z9 47 U1 0 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 22 PY 2001 VL 86 IS 4 BP 660 EP 663 DI 10.1103/PhysRevLett.86.660 PG 4 WC Physics, Multidisciplinary SC Physics GA 394TT UT WOS:000166539900026 PM 11177906 ER PT J AU Yoon, YG Mazzoni, MSC Choi, HJ Ihm, J Louie, SG AF Yoon, YG Mazzoni, MSC Choi, HJ Ihm, J Louie, SG TI Structural deformation and intertube conductance of crossed carbon nanotube junctions SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM WIRES; SINGLE-WALL; TUBULES; PSEUDOPOTENTIALS; DEVICES AB We present a first-principles study of the structure and quantum electronic conductance of junctions consisting of two crossed (5, 5) single-walled carbon nanotubes. The structures are determined by constrained minimization of total energy at a given force between the two tubes, simulating the effects of substrate-tube attraction or an applied force. We find that the intertube contact distance is very sensitive to the applied force in the range of 0-10 nN. The intertube conductance is sizable for realistic deformation expected from substrate interaction. The results explain the recent transport data on crossed nanotubes and show that these systems may be potentially useful as electromechanical devices. DOI: 10.1103/PhysRevLett.86.688. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. RP Yoon, YG (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Yoon, Young-Gui/C-2978-2008; Choi, Hyoung Joon/N-8933-2015 OI Yoon, Young-Gui/0000-0002-1071-8628; Choi, Hyoung Joon/0000-0001-8565-8597 NR 28 TC 73 Z9 73 U1 1 U2 15 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 22 PY 2001 VL 86 IS 4 BP 688 EP 691 DI 10.1103/PhysRevLett.86.688 PG 4 WC Physics, Multidisciplinary SC Physics GA 394TT UT WOS:000166539900033 PM 11177913 ER PT J AU Morozov, VA Meyer, FW AF Morozov, VA Meyer, FW TI Path-dependent neutralization of multiply charged Ar ions incident on Au(110) SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRON-EMISSION; ANGLE SCATTERING; ENERGY-LOSS; ALKALI-ION; SURFACE; ATOMS; TIME AB Using a time-of-flight technique we have investigated the backscattering of 5 keV Ar2+ and Ar11+ projectiles from Au(110). A strong dependence an target azimuth is found for the neutral flux resulting from (quasi)binary projectile collisions with target atoms, while for the charged components only a weak dependence is seen. A deconvolution of the observed dependences based on trajectory simulations clearly shows site-specific neutralization differences between the Various possible binary collisions occurring with surface atoms. Such differences must be properly accounted for in order to permit meaningful comparison with theory. DOI: 10.1103/PhysRevLett.86.736. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Morozov, VA (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 28 TC 18 Z9 18 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 22 PY 2001 VL 86 IS 4 BP 736 EP 739 DI 10.1103/PhysRevLett.86.736 PG 4 WC Physics, Multidisciplinary SC Physics GA 394TT UT WOS:000166539900045 PM 11177925 ER PT J AU Wiklund, K Kaufman, AN AF Wiklund, K Kaufman, AN TI Hermitian structure for linear internal waves in sheared flow SO PHYSICS LETTERS A LA English DT Article ID MODE CONVERSION; FLUID AB Motivated by the problem of linear mode conversion between ducted internal gravity waves in a sheared Row, we construct a variational principle based on a Hermitian evolution operator, obtained from Larsson's Hamiltonian formalism. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Wiklund, K (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 11 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 JAN 22 PY 2001 VL 279 IS 1-2 BP 67 EP 69 DI 10.1016/S0375-9601(00)00810-0 PG 3 WC Physics, Multidisciplinary SC Physics GA 397QL UT WOS:000166706700012 ER PT J AU Hyman, JM Li, J Stanley, EA AF Hyman, JM Li, J Stanley, EA TI The initialization and sensitivity of multigroup models for the transmission of HIV SO JOURNAL OF THEORETICAL BIOLOGY LA English DT Article ID VIRUS TYPE-1 INFECTION; AIDS; UNCERTAINTY; PROGRESSION; EXAMPLE; PLASMA; RISK AB We study two multigroup mathematical models of the spread of HIV. In the differential infectivity model, the infected population is divided into groups according to their infectiousness, and HIV is primarily spread by a small, highly infectious, group of superspreaders. In the staged-progression model, every infected individual goes through a series of infection stages and the virus is primarily spread by individuals in an initial highly infectious stage or in the late stages of the disease. We demonstrate the importance of choosing appropriate initial conditions, and define a new approach to distributing the initial population among the subgroups so as to minimize the artificial transients in the solutions due to unbalanced initial conditions. We demonstrate that the rate of removal in and out of a population is an important, yet often neglected, effect. We also illustrate the importance of distinguishing between the number of partners a person has and the number of contacts per partner. By assuming that people with many partners have fewer contacts per partner than people with few partners, we found that the epidemic is less sensitive to the partner acquisition rate than one might expect. However, because the probability of transmission of HIV per contact is low, the epidemic is very sensitive to the number of contacts per partner. Modeling this distinction is particularly important when estimating the impact of programs which encourage people to have fewer sexual partners. (C) 2001 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Div Theoret, Los Alamos, NM 87545 USA. Univ Alabama, Dept Math Sci, Huntsville, AL 35899 USA. RP Hyman, JM (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Div Theoret, MS-B284, Los Alamos, NM 87545 USA. RI Barley, Kamal/F-9579-2011 OI Barley, Kamal/0000-0003-1874-9813 NR 23 TC 16 Z9 19 U1 1 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-5193 J9 J THEOR BIOL JI J. Theor. Biol. PD JAN 21 PY 2001 VL 208 IS 2 BP 227 EP 249 DI 10.1006/jtbi.2000.2214 PG 23 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA 394CT UT WOS:000166507000009 PM 11162066 ER PT J AU Marquet, C Piquemal, F Arnold, R Augier, C Baker, J Barabash, A Bing, O Blum, D Brudanin, V Caffrey, J Campagne, JE Caurier, E Dassie, D Egorov, V Errahmane, K Eschbach, R Filipova, T Guyonnet, JL Jollet, C Jullian, S Hubert, F Hubert, P Kisel, I Kochetov, O Kornoukhov, VN Kovalenko, V Lalanne, D Laplanche, F Leccia, F Linck, I Longuemare, C Mauger, F Nicholson, HW Nikolic-Audit, I Ohsumi, H Pilugin, I Reyss, JL Sarazin, X Scheibling, F Stekl, I Suhonen, J Sutton, CS Szklarz, G Timkin, V Tretyak, V Umatov, V Vala, L Vanyushin, I Vareille, A Vorobel, V Vylov, T AF Marquet, C Piquemal, F Arnold, R Augier, C Baker, J Barabash, A Bing, O Blum, D Brudanin, V Caffrey, J Campagne, JE Caurier, E Dassie, D Egorov, V Errahmane, K Eschbach, R Filipova, T Guyonnet, JL Jollet, C Jullian, S Hubert, F Hubert, P Kisel, I Kochetov, O Kornoukhov, VN Kovalenko, V Lalanne, D Laplanche, F Leccia, F Linck, I Longuemare, C Mauger, F Nicholson, HW Nikolic-Audit, I Ohsumi, H Pilugin, I Reyss, JL Sarazin, X Scheibling, F Stekl, I Suhonen, J Sutton, CS Szklarz, G Timkin, V Tretyak, V Umatov, V Vala, L Vanyushin, I Vareille, A Vorobel, V Vylov, T CA NEMO Collaboration TI Influence of neutrons and gamma-rays in the Frejus underground laboratory on the NEMO experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE neutron; gamma-ray; Monte Carlo simulation; background; double-beta decay ID DOUBLE-BETA-DECAY AB To be sensitive to an effective Majorana neutrino mass, [m(v)], on the order of 0.1 eV. the NEMO 3 double beta (beta beta (0v)) decay experiment requires precise knowledge and control of the backgrounds. The effect of neutrons and gamma -rays from the Frejus underground laboratory (LSM, Laboratoire Souterrain de Modane) has been studied during 10 700 h of data collection. The data were taken with a NEMO 2 prototype detector using different shield configurations. Monte Carlo calculations with GEANT/MICAP code and a new library of gamma -rays from neutron captures are presented. The implied consequences for the NEMO 3 detector which is under construction are discussed. The neutrinoless double beta decay background induced by neutrons and gamma -rays within the LSM will be suppressed to the very suitable level of 0.1 event in a live time of five years given the appropriate shield and magnetic field, (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEN Bordeaux Gradignan, IN2P3, CNRS, F-33175 Gradignan, France. Univ Bordeaux 1, F-33175 Gradignan, France. Univ Strasbourg 1, F-67037 Strasbourg, France. IN2P3, CNRS, IReS, F-67037 Strasbourg, France. Univ Paris 11, F-91405 Orsay, France. IN2P3, CNRS, LAL, F-91405 Orsay, France. INEEL, Idaho Falls, ID 83415 USA. Inst Theoret & Expt Phys, Moscow 117259, Russia. Joint Inst Nucl Res, Dubna 141980, Russia. Univ Caen, F-14032 Caen, France. IN2P3, CNRS, LPC, F-14032 Caen, France. Mt Holyoke Coll, S Hadley, MA 01075 USA. CNRS, LSCE, F-91190 Gif Sur Yvette, France. Czech Tech Univ, FNSPE, Prague, Czech Republic. Univ Jyvaskyla, SF-40351 Jyvaskyla, Finland. Charles Univ Prague, Prague, Czech Republic. RP Marquet, C (reprint author), IReS, 23 Rue du Loess, F-67037 Strasbourg 2, France. EM christine.marquet@ires.in2p3.fr RI Vala, Ladislav/L-4938-2016; Barabash, Alexander/S-8851-2016 NR 15 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 21 PY 2001 VL 457 IS 3 BP 487 EP 498 DI 10.1016/S0168-9002(00)00789-0 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 398KL UT WOS:000166755600008 ER PT J AU Marchesini, S Ulrich, O Faigel, G Tegze, M Belakhovsky, M Simionovici, AS AF Marchesini, S Ulrich, O Faigel, G Tegze, M Belakhovsky, M Simionovici, AS TI Instrumental development of X-ray atomic holography at ESRF SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE holography; X-ray; focusing optics; undulator radiation ID RESOLUTION AB We have developed an X-ray Fluorescence Holography (XFH) setup at the European Synchrotron Radiation Facility (ESRF). The main difficulty inherent to XFH is that the holographic signal is in the low 10(-3) range compared to the background isotropic fluorescent radiation. This requires a very pure fluorescent signal and the highest possible count rate. Therefore, we designed a focusing analyser system with large solid angle acceptance. The photons of the focused beam were counted by an avalanche photodiode in single-photon counting mode up to a few MHz. At even higher intensity, we switched to a Si diode working in the photocurrent mode. Due to the relatively weak requirements on the bandwidth of the exciting incident radiation, we could directly use the undulator beam, discriminating lower harmonics by an absorber and higher ones by reflecting the beam on a Si mirror. By developing a fast. continuous "spiral" scanning technique, a full hologram could be recorded in 30 sec. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEA Grenoble, Dept Rech Fondamentale Mat Condensee, Serv Phys Mat & Microstruct, F-38054 Grenoble 9, France. Res Inst Solid State Phys & Opt, H-1525 Budapest, Hungary. European Synchrotron Radiat Facil, F-38043 Grenoble, France. RP Marchesini, S (reprint author), Lawrence Berkeley Natl Lab, Div Mat Sci, MS 2-100,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Marchesini, Stefano/A-6795-2009; BM32, CRG IF/I-7017-2015 NR 9 TC 15 Z9 15 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 21 PY 2001 VL 457 IS 3 BP 601 EP 606 DI 10.1016/S0168-9002(00)00791-9 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 398KL UT WOS:000166755600021 ER PT J AU Bottcher, M Fryer, CL AF Bottcher, M Fryer, CL TI X-ray spectral features from gamma-ray bursts: Predictions of progenitor models SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; supernovae : general; X-rays : bursts ID BLACK-HOLE; SUPERNOVAE; EVOLUTION; EMISSION; PHASE; LINE AB We investigate the potentially observable prompt or delayed X-ray spectral features from the currently popular gamma-ray burst (GRB) models. During the evolution of many GRB progenitors, a disk around the central GRB source is produced. Shock heating as the GRB ejecta collide with the disk may produce observable X-ray features. We first summarize predictions deduced from previous calculations that invoke photoionization and relativistic blast waves. We then calculate the quasi-thermal X-ray line features produced assuming the ejecta are nonrelativistic (which is more likely for the disk interactions of many GRB models). In the framework of the hypernova/collapsar model, delayed (a few days to several months after the GRB) bursts of line-dominated, thermal X-ray emission may be expected. The Hemerger scenario predicts similar X-ray emission-line bursts less than or similar to a few days after the GRB. These X-ray signatures should be observable with Chandra and XMM-Newton out to at least z similar to 1. Weak emission-line features less than or similar to a few days after the GRB may also result from the "supranova" GRB scenario. In all three cases, significant X-ray absorption features, in particular during the prompt GRB phase, are expected. No significant X-ray spectral features should result from compact-object binary mergers. C1 Rice Univ, Houston, TX 77005 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bottcher, M (reprint author), Rice Univ, MS 108,6100 S Main St, Houston, TX 77005 USA. NR 28 TC 23 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 JAN 20 PY 2001 VL 547 IS 1 BP 338 EP 344 DI 10.1086/318346 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 395RN UT WOS:000166595200036 ER PT J AU Guo, CL Taylor, AJ AF Guo, CL Taylor, AJ TI Ultrafast dynamics of thermal and nonthermal structural changes in metals SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Review ID FEMTOSECOND LASER-PULSES; ELECTRON THERMALIZATION; OPTICAL-PROPERTIES; PHASE-TRANSITION; GOLD-FILMS; ABSORPTION; EXCITATION; ALUMINUM; COPPER; GAAS AB Although structural phase changes in metals are a vital problem due to its fundamental importance as well as wide applicability in materials processing and manufacturing, the underlying physics of this process is still not fully understood and remains only at a phenomenological level. The study of the dynamics associated with structural changes only becomes possible recently with advances of femtosecond laser techniques. In this paper, we discuss our experimental results in the ultrafast dynamics of structural changes in metals induced by both thermal and nonthermal processes by monitoring materials states through their transient dielectric constants. These results lead to a more complete understanding of the physical mechanism of structural phase changes in metals. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. RP Guo, CL (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. NR 43 TC 1 Z9 1 U1 2 U2 7 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD JAN 20 PY 2001 VL 15 IS 2 BP 101 EP 115 DI 10.1142/S0217979201002588 PG 15 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 410PP UT WOS:000167448600001 ER PT J AU Trebotich, DP Colella, P AF Trebotich, DP Colella, P TI A projection method for incompressible viscous flow on moving quadrilateral grids SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE projection methods; deformable domains; incompressible flow; Navier-Stokes equations ID NAVIER-STOKES EQUATIONS; SIMULATION; DOMAINS AB We present a second-order accurate projection method for numerical solution of the incompressible Navier-Stokes equations on moving quadrilateral grids. Our approach is a generalization of the Bell-Colella-Glaz (BCG) predictor-corrector method for incompressible flow. Irregular geometry is represented in terms of a moving, body-fitted cylindrical coordinate system. Mapped coordinates are used to smoothly transform in both time and space the moving domain onto a logically rectangular domain which is fixed in time. To treat the time dependence and inhomogeneities in the incompressibility constraint introduced by the presence of deforming boundaries. wt: introduce a nontrivial splitting of the velocity held into vortical and potential components to eliminate the inhomogeneous terms in the constraint and a generalization of the BCG algorithm to treat time-dependent constraints. The method is second-order accurate in space and time. has a time step constraint determined by the advective CFL condition, and requires the solution of well-behaved linear systems amenable to the use of fast iterative methods. We demonstrate the method on the specific example of viscous incompressible flow in an axisymmetric deforming tube. (C) 2001 Academic Press. C1 Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Appl Numer Algorithms Grp, Berkeley, CA 94720 USA. RP Trebotich, DP (reprint author), Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. NR 31 TC 14 Z9 14 U1 0 U2 3 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JAN 20 PY 2001 VL 166 IS 2 BP 191 EP 217 DI 10.1006/jcph.2000.6654 PG 27 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 398YX UT WOS:000166785000001 ER PT J AU Ledieu, J Muryn, CA Thornton, G Diehl, RD Lograsso, TA Delaney, DW McGrath, R AF Ledieu, J Muryn, CA Thornton, G Diehl, RD Lograsso, TA Delaney, DW McGrath, R TI C-60 adsorption on the quasicrystalline surface of Al70Pd21Mn9 SO SURFACE SCIENCE LA English DT Article DE low energy electron diffraction (LEED); scanning tunneling microscopy; surface structure, morphology, roughness and; topography; alloys ID SCANNING-TUNNELING-MICROSCOPY; ENERGY-ELECTRON DIFFRACTION; AL-PD-MN; QUASI-CRYSTAL; SINGLE-GRAIN; AL68PD23MN9; STM; MOLECULES; LEED AB Room temperature adsorption of C-60 on the flat quasicrystalline surface of Al70Pd21Mn9 has been investigated using scanning tunnelling microscopy. A dispersed overlayer is formed at low coverage, with avoidance of step-edges. There is no evidence of island formation or clustering. As the coverage is increased, a higher density layer is formed with no evidence of the formation of hexagonal ordered adsorbate structures seen on other substrates. This is followed by the onset of second layer formation. A range of bonding sites for C60 molecules is implied from measurements of apparent molecular heights and from thermal effects. Detailed analysis of the surface at a low coverage (similar to0.065 ML) provides evidence of adsorbate local order, with Fibonacci (iota -scaling) relationships between the C-60 molecules. Where this occurs, the preferred adsorption site is tentatively identified as the pentagonal hollow. These local correlations however are not found to extend over larger regions of the surface. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Liverpool, Dept Phys, Surface Sci Res Ctr, Liverpool L69 3BX, Merseyside, England. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Univ Manchester, Dept Chem, Manchester M13 9PL, Lancs, England. Univ Liverpool, Surface Sci Res Ctr, Liverpool L69 3BX, Merseyside, England. RP McGrath, R (reprint author), Univ Liverpool, Dept Phys, Surface Sci Res Ctr, Liverpool L69 3BX, Merseyside, England. RI McGrath, Ronan/A-1568-2009; Ledieu, Julian/F-1430-2010 OI McGrath, Ronan/0000-0002-9880-5741; NR 24 TC 46 Z9 46 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JAN 20 PY 2001 VL 472 IS 1-2 BP 89 EP 96 DI 10.1016/S0039-6028(00)00924-9 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 399TE UT WOS:000166827800012 ER PT J AU Saiz, E Tomsia, AP Cannon, RM AF Saiz, E Tomsia, AP Cannon, RM TI Triple line ridging and attachment in high-temperature wetting SO SCRIPTA MATERIALIA LA English DT Article DE metals; ceramics; liquids; high temperature; surfaces; interfaces ID WETTABILITY; METALS C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Saiz, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. NR 12 TC 32 Z9 32 U1 0 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JAN 19 PY 2001 VL 44 IS 1 BP 159 EP 164 DI 10.1016/S1359-6462(00)00549-2 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 399JP UT WOS:000166808100026 ER PT J AU Yonker, CR Palmer, BJ AF Yonker, CR Palmer, BJ TI Investigation of CO2/fluorine interactions through the intermolecular effects on the H-1 and F-19 shielding of CH3F and CHF3 at various temperatures and pressures SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID SUPERCRITICAL CARBON-DIOXIDE; MOLECULAR MODELING APPROACH; ROVIBRATIONAL MOTION; ETHANE; NMR; HEXAFLUOROETHANE; DEPENDENCE; DYNAMICS; LIQUID; PHASE AB The nuclear shielding for both the H-1 and F-19 nuclei of CH3F and CHF3 was investigated as a function of pressure and temperature. The density region investigated extended from low, gaslike conditions to study pairwise intermolecular interactions to high, liquidlike densities to study multibody effects on nuclear shielding. The temperature range was from 30 to 150 degreesC. Neat samples of CH3F and CHF3, along with CO2 mixtures of these fluorocarbons, were investigated by H-1 and F-19 high-pressure NMR. Molecular dynamics simulations were undertaken to describe the pair-distribution functions for both the neat samples and mixtures to aid in the interpretation of the H-1 and (1)9F nuclear shielding determined from high-pressure NMR. The NMR spectra of the neat fluorornethanes and their CO2 mixtures suggest that there are no distinct or specific interactions between the fluoromethanes and CO2 and that as the temperature increases the multibody effects play less of a role in nuclear shielding. C1 Pacific NW Natl Lab, Environm & Energy Sci Div, Richland, WA 99352 USA. RP Yonker, CR (reprint author), Pacific NW Natl Lab, Environm & Energy Sci Div, Richland, WA 99352 USA. NR 29 TC 54 Z9 54 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 18 PY 2001 VL 105 IS 2 BP 308 EP 314 DI 10.1021/jp0031202 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 393VR UT WOS:000166490800002 ER PT J AU Chawla, R Shukla, A Futrell, J AF Chawla, R Shukla, A Futrell, J TI Collision-induced dissociation of nitrobenzene molecular cations at low energies by crossed-beam tandem mass spectrometry SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID SPECTRAL FRAGMENTATION PATHWAYS; ELECTRON-IMPACT FRAGMENTATION; POLYATOMIC IONS; DYNAMICS; DECOMPOSITION; MECHANISMS; EXPLOSIVES; SCATTERING AB The dynamics of the collision-induced dissociation (CID) of the nitrobenzene molecular ipn have been investigated in the energy range of 3 eV-50 eV in the center-of-mass (CM) reference frame using a crossed-beam tandem hybrid mass spectrometer-supersonic molecular beam instrument. At these collision energies the dominant CID channel is loss of NO2 from the molecular ion and contribution from competing channels is very small. At 3.1 eV collision energy, fragment ions, C6H5+, are fully backward scattered and as collision energy is increased the most probable scattering angle moves in the forward scattering region but remains above zero up to 50 eV energy. These results suggest that small impact parameter impulsive collisions dominate this CID process in the low collision energy range, The energy transfer in the collisional activation step does not change significantly with increase in collision energy and corresponds to about 0.6 eV above the thermochemical threshold even though the molecular ions were formed by 70 eV energy electrons. There are no apparent changes in the dynamics features of the activation/dissociation process in going from 3 to 50 eV collision energy except the decrease in the maximum of the CM scattering angle. These results suggest that there is no change in the activation/dissociation mechanism for this CID process, We further suggest, based upon the energy loss measurements, that this dissociation process is nor direct, instead it proceeds via ion-neutral complex C6H5+. . . NO2, as proposed by Osterheld, Baer, and Brauman (Osterheld, T. H.; Baer, T.; Brauman, J. A. J. Aln. Chem. Sec. 1993, 115, 6284) and competes with the loss of NO via nitro-nitrite rearrangement. C1 Univ Delaware, Dept Chem & Biochem, Newark, DE 19716 USA. RP Shukla, A (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, MS K8-96,BOB 999, Richland, WA 99352 USA. NR 41 TC 5 Z9 5 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 18 PY 2001 VL 105 IS 2 BP 349 EP 353 DI 10.1021/jp003075y PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 393VR UT WOS:000166490800008 ER PT J AU Hsu, CP Hirata, S Head-Gordon, M AF Hsu, CP Hirata, S Head-Gordon, M TI Excitation energies from time-dependent density functional theory for linear polyene oligomers: Butadiene to decapentaene SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID CONFIGURATION-INTERACTION METHOD; AB-INITIO CALCULATIONS; EXCITED-STATES; ELECTRON-IMPACT; RESPONSE THEORY; APPROXIMATION; 1,3-BUTADIENE; SPECTROSCOPY; TRANSITIONS; ABSORPTION AB Time-dependent density functional theory (TDDFT) is applied to calculate vertical excitation energies of trans-1,3-butadiene, trans-trans-1,3,5-hexatriene, all-trans-1,3,5,7-octatetraene, and all-trans-1,3,5,7,9-decapentaene. Attachment and detachment densities for transitions in butadiene and decapentaene from the ground state to the 2 (1)A(g) and 1 (1)B(u) excited states are also calculated and analyzed. Based on comparisons with experimental results and high level ab initio calculations in the literature, significant improvement over configuration-interaction singles is observed for the 2 (1)A(g) state of the polyenes, which has been known to have significant double excitation character. For the 1 (1)B(u) state, TDDFT underestimates the excitation energy by 0.4-0.7 eV. In this case we have observed a significant difference between the results for TDDFT and TDDFT within the Tamm-Dancoff approximation, both in excitation energies and, at least for butadiene, in the character of the excited state. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Head-Gordon, M (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Hsu, Chao-Ping/E-1303-2011 OI Hsu, Chao-Ping/0000-0002-7187-427X NR 53 TC 213 Z9 214 U1 2 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 18 PY 2001 VL 105 IS 2 BP 451 EP 458 DI 10.1021/jp0024367 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 393VR UT WOS:000166490800021 ER PT J AU Kadavanich, AV Kippeny, TC Erwin, MM Pennycook, SJ Rosenthal, SJ AF Kadavanich, AV Kippeny, TC Erwin, MM Pennycook, SJ Rosenthal, SJ TI Sublattice resolution structural and chemical analysis of individual CdSe nanocrystals using atomic number contrast scanning transmission electron microscopy and electron energy loss spectroscopy SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SEMICONDUCTOR QUANTUM DOTS; CADMIUM SELENIDE NANOCRYSTALS; PERMANENT DIPOLE-MOMENT; LIGHT-EMITTING-DIODES; IMAGE-RECONSTRUCTION; OPTICAL-PROPERTIES; CHARGE SEPARATION; PHOTOLUMINESCENCE; CRYSTALS; NANOCLUSTERS AB Atomic number contrast scanning transmission electron microscopy (Z-STEM), with atomic resolution and sub-nanometer resolution scanning transmission electron microscope electron energy loss spectroscopy (STEM-EELS), was used to study single colloidal CdSe semiconductor nanocrystals embedded in MEH-PPV polymer films. The atomic column-resolved Z-STEM image provides information both on the lateral shape of the nanocrystal, as well as the relative thickness of the individual atom columns from a single image. The three-dimensional shape profile reconstructed from the data matches the predicted model. Furthermore, the sublattice is resolved so the polar surfaces can be uniquely identified. Sub-nanometer resolution EELS measurements on an individual nanocrystal indicate the presence of oxygen. The spatial distribution of the oxygen signal in the EELS measurement suggests a thin oxide layer on the nanocrystal surface. C1 Vanderbilt Univ, Dept Chem, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Rosenthal, SJ (reprint author), Vanderbilt Univ, Dept Chem, Box 1583, Nashville, TN 37235 USA. NR 71 TC 22 Z9 23 U1 1 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 18 PY 2001 VL 105 IS 2 BP 361 EP 369 DI 10.1021/jp002974j PG 9 WC Chemistry, Physical SC Chemistry GA 393VT UT WOS:000166490900004 ER PT J AU Ding, WP Li, SZ Meitzner, GD Iglesia, E AF Ding, WP Li, SZ Meitzner, GD Iglesia, E TI Methane conversion to aromatics on Mo/H-ZSM5: Structure of molybdenum species in working catalysts SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MO-BASED CATALYSTS; CARBIDE CATALYSTS; UNSUPPORTED POWDERS; ZEOLITE CATALYSTS; BENZENE; AROMATIZATION; DEHYDROGENATION; MO/HZSM-5; COMPOSITES; MO/ZSM-5 AB The structure and density of Mo species in Mo/H-ZSM5 during catalytic CH4 reactions was investigated using in-situ X-ray absorption spectroscopy (XAS), temperature-programmed oxidation after reaction, and the isotopic exchange of D-2 with OH groups in H-ZSM5 before and after CH4 reactions. These methods reveal that CHI reactions cause exchanged Mo2O52+ dimers, formed from physical mixtures of MoO3 and H-ZSM5, to reduce and carburize to form small (0.6-1 nm) MoCx clusters with the concurrent regeneration of the bridging OH groups that were initially replaced by Mo oxo dimers during exchange. In this manner, catalytically inactive Mo oxo species activate in contact with CH4 to form the two sites required for the conversion of CH4 to aromatics: MoCx for C-H bond activation and initial C-C bond formation and acid sites for oligomerization and cyclization of C2+ hydrocarbons to form stable aromatics. These MoCx clusters resist agglomeration during methane reactions at 950 K for > 10 h. The Bronsted acid sites formed during carburization and oligomerization of MoCx species ultimately become covered with hydrogen-deficient reaction intermediates (H/C similar to 0.2) or unreactive deposits. The highly dispersed nature of the MoCx clusters was confirmed by detailed simulations of the XAS radial structure function and by the low temperatures required for the complete oxidation of these MoCx species compared with bulk Mo2C. Initial CH4 reactions with MoOx precursors are stoichiometric and lead first to the removal of oxygen as CO, CO2, and H2O and to the introduction of carbidic carbons into the reduced structures. As carbidic carbon passivates the surface, C-H bond activation reactions become catalytic by the coupling of this activation step with the removal of the resulting CH, species to form C-2 hydrocarbons, which desorb to re-form the MoC, sites required for C-H bond activation steps. C1 Univ Calif Berkeley, Div Mat Sci, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Nanjing Univ, Dept Chem, Nanjing 210093, Peoples R China. RP Iglesia, E (reprint author), Univ Calif Berkeley, Div Mat Sci, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Iglesia, Enrique/D-9551-2017 OI Iglesia, Enrique/0000-0003-4109-1001 NR 39 TC 128 Z9 129 U1 7 U2 88 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 18 PY 2001 VL 105 IS 2 BP 506 EP 513 DI 10.1021/jp0030692 PG 8 WC Chemistry, Physical SC Chemistry GA 393VT UT WOS:000166490900021 ER PT J AU Perkins, CL Henderson, MA McCready, DE Herman, GS AF Perkins, CL Henderson, MA McCready, DE Herman, GS TI Comment on "Electron source in photoinduced hydrogen production on Pt-supported TiO2 particles" SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Perkins, CL (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd,MS 3215, Golden, CO 80401 USA. NR 7 TC 4 Z9 4 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 18 PY 2001 VL 105 IS 2 BP 595 EP 596 DI 10.1021/jp001793e PG 2 WC Chemistry, Physical SC Chemistry GA 393VT UT WOS:000166490900033 ER PT J AU Bianco, PR Brewer, LR Corzett, M Balhorn, R Yeh, Y Kowalczykowski, SC Baskin, RJ AF Bianco, PR Brewer, LR Corzett, M Balhorn, R Yeh, Y Kowalczykowski, SC Baskin, RJ TI Processive translocation and DNA unwinding by individual RecBCD enzyme molecules SO NATURE LA English DT Article ID DOUBLE-STRANDED DNA; ESCHERICHIA-COLI; HELICASE ACTIVITY; DUPLEX DNA; BINDING; ASSAY; DISPLACEMENT; FLUORESCENT; RECA AB RecBCD enzyme is a processive DNA helicase(1) and nuclease(2) that participates in the repair of chromosomal DNA through homologous recombination(3,4). We have visualized directly the movement of individual RecBCD enzymes on single molecules of double-stranded DNA (dsDNA). Detection involves the optical trapping of solitary, fluorescently tagged dsDNA molecules that are attached to polystyrene beads, and their visualization by fluorescence microscopy(5,6). Both helicase translocation and DNA unwinding are monitored by the displacement of fluorescent dye from the DNA by the enzyme(7). Here we show that unwinding is both continuous and processive, occurring at a maximum rate of 972 +/- 172 base pairs per second (0.30 mum s(-1)), with as many as 42,300 base pairs of dsDNA unwound by a single RecBCD enzyme molecule. The mean behaviour of the individual RecBCD enzyme molecules corresponds to that observed in bulk solution. C1 Univ Calif Davis, Microbiol Sect, Davis, CA 95616 USA. Univ Calif Davis, Sect Mol & Cellular Biol, Davis, CA 95616 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Elect Engn Technol Div, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Biotechnol Res Program, Livermore, CA 94550 USA. RP Kowalczykowski, SC (reprint author), Univ Calif Davis, Microbiol Sect, Davis, CA 95616 USA. RI Brewer, Laurence/G-4056-2012 NR 19 TC 212 Z9 215 U1 5 U2 27 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 18 PY 2001 VL 409 IS 6818 BP 374 EP 378 DI 10.1038/35053131 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 392VY UT WOS:000166434300055 PM 11201750 ER PT J AU Brodsky, SJ Chudakov, E Hoyer, P Laget, JM AF Brodsky, SJ Chudakov, E Hoyer, P Laget, JM TI Photoproduction of charm near threshold SO PHYSICS LETTERS B LA English DT Article ID COLOR TRANSPARENCY; INTRINSIC CHARM; VECTOR-MESONS; DEUTERON; QCD; QUARK; SYSTEMS; NUCLEI AB Charm and bottom production near threshold is sensitive to the multi-quark, gluonic, and hidden-color correlations of hadronic and nuclear wavefunctions in QCD since all of the target's constituents must act coherently within the small interaction volume of the heavy quark production subprocess. Although such multi-parton subprocess cross sections are suppressed by powers of 1/m(Q)(2), they have less phase-space suppression and can dominate the contributions of the leading-twist single-gluon subprocesses in the threshold regime. The small rates for open and hidden charm photoproduction at threshold call for a dedicated facility. (C) 2001 Published by Elsevier Science B.V. C1 CEA Saclay, DAPNIA, SPhN, F-91191 Gif Sur Yvette, France. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. NORDITA, DK-2100 Copenhagen, Denmark. RP Laget, JM (reprint author), CEA Saclay, DAPNIA, SPhN, F-91191 Gif Sur Yvette, France. NR 26 TC 23 Z9 23 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JAN 18 PY 2001 VL 498 IS 1-2 BP 23 EP 28 DI 10.1016/S0370-2693(00)01373-3 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 397YK UT WOS:000166726300004 ER PT J AU Tannenbaum, MJ AF Tannenbaum, MJ TI The distribution function of the event-by-event average p(T) for statistically independent emission SO PHYSICS LETTERS B LA English DT Article DE relativistic heavy-ion collisions; event-by-event analysis; distributions; fluctuations ID MULTIPLICITY DISTRIBUTIONS; COLLISIONS; ENERGY AB For statistically independent emission, a closed form of the distribution function for M-pT, the event-by-event average p(T), can be obtained. A recent NA49 measurement satisfies this conditions and a distribution is obtained which is in excellent agreement with the NA49 measurement. (C) 2001 Published by Elsevier Science B.V. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Tannenbaum, MJ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. OI Tannenbaum, Michael/0000-0002-8840-5314 NR 9 TC 30 Z9 30 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JAN 18 PY 2001 VL 498 IS 1-2 BP 29 EP 34 DI 10.1016/S0370-2693(00)01325-3 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 397YK UT WOS:000166726300005 ER PT J AU Huang, MH Wu, YY Feick, H Tran, N Weber, E Yang, PD AF Huang, MH Wu, YY Feick, H Tran, N Weber, E Yang, PD TI Catalytic growth of zinc oxide nanowires by vapor transport SO ADVANCED MATERIALS LA English DT Article ID ROOM-TEMPERATURE; ZNO; NANOTUBES C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Mat Sci & Engn, Div Sci Mat, Berkeley, CA 94720 USA. RP Yang, PD (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Wu, Yiying/A-3949-2011 NR 26 TC 2176 Z9 2232 U1 42 U2 463 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 JAN 16 PY 2001 VL 13 IS 2 BP 113 EP 116 DI 10.1002/1521-4095(200101)13:2<113::AID-ADMA113>3.0.CO;2-H 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 401LY UT WOS:000166930100003 ER PT J AU Paul-Pletzer, K Palnitkar, SS Jimenez, LS Morimoto, H Parness, J AF Paul-Pletzer, K Palnitkar, SS Jimenez, LS Morimoto, H Parness, J TI The skeletal muscle ryanodine receptor identified as a molecular target of [H-3]azidodantrolene by photoaffinity labeling SO BIOCHEMISTRY LA English DT Article ID CA2+ RELEASE CHANNEL; PORE-FORMING SEGMENT; DYSTROPHY TYPE 2A; SARCOPLASMIC-RETICULUM; MALIGNANT HYPERTHERMIA; DIHYDROPYRIDINE RECEPTOR; CALCIUM-RELEASE; BINDING-SITES; PHYSIOLOGICAL-FUNCTION; ENDOGENOUS EFFECTORS AB Dantrolene is a skeletal muscle relaxant which acts by inhibiting intracellular Ca2+ release from sarcoplasmic reticulum (SR). It is used primarily in the treatment of malignant hyperthermia (MH), a pharmacogenetic sensitivity to volatile anesthetics resulting in massive intracellular Ca2+ release. Determination of the site and mechanism of action of dantrolene should contribute to the understanding of the regulation of intracellular Ca2+ release in skeletal muscle. Photoaffinity labeling of porcine SR with [H-3]azidodantrolene, a photoactivatable analogue of dantrolene, has identified a 160 kDa SR protein with immunologic cross-reactivity to skeletal muscle ryanodine receptor (RyR) as a possible target [Palnitkar et al. (1999) J. Med. Chem. 42, 1872-1880]. Here we demonstrate specific, AMP-PCP-enhanced, [H-3]azidodantrolene photolabeling of both the RyR monomer and a 160 or 172 kDa protein in porcine and rabbit SR, respectively. The 160/172 kDa protein is shown to be the NH2-terminus of the RyR cleaved from the monomer by an endogenous protease activity consistent with that of n-calpain. MALDI-mass spectrometric analysis of the porcine 160 kDa protein identifies it as the 1400 amino acid NH2-terminal fragment of the skeletal muscle RyR reportedly generated by n-calpain [Shevchenko et al. (1998) J. Membr. Biol. 161, 33-34]. Immunoprecipitation of solubilized, [H-3]azidodantrolene-photolabeled SR protein reveals that the cleaved 160/172 kDa protein remains associated with the C-terminal, 410 kDa portion of the RyR. [H-3]Dantrolene binding to both the intact and the n-calpain-cleaved channel RyR is similarly enhanced by AMP-PCP. n-Calpain cleavage of the RyR does not affect [H-3]dantrolene binding in the presence of AMP-PCP, but depresses drug binding in the absence of nucleotide. These results demonstrate that the NH2-terminus of the RyR is a molecular target for dantrolene, and suggest a regulatory role for both n-calpain activity and ATP in the interaction of dantrolene with the RyR in vivo. C1 Univ Med & Dent New Jersey, Robert Wood Johnson Med Sch, Dept Anesthesia, New Brunswick, NJ 08901 USA. Univ Med & Dent New Jersey, Robert Wood Johnson Med Sch, Dept Pharmacol, New Brunswick, NJ 08901 USA. Univ Med & Dent New Jersey, Robert Wood Johnson Med Sch, Dept Pediat, New Brunswick, NJ 08901 USA. Rutgers State Univ, Dept Chem, Piscataway, NJ 08854 USA. EO Lawrence Berkeley Natl Lab, Natl Tritium Labelling Facil, Berkeley, CA 94720 USA. EO Lawrence Berkeley Natl Lab, Div Phys Biosci, Berkeley, CA 94720 USA. RP Parness, J (reprint author), Univ Med & Dent New Jersey, Robert Wood Johnson Med Sch, Dept Anesthesia, 125 Paterson St,Clin Acad Bldg,Suite 3100, New Brunswick, NJ 08901 USA. FU NIAMS NIH HHS [5RO1 AR45593-02] NR 63 TC 29 Z9 29 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JAN 16 PY 2001 VL 40 IS 2 BP 531 EP 542 DI 10.1021/bi001502s PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 393YH UT WOS:000166496900027 PM 11148048 ER PT J AU Haschke, JM Allen, TH Morales, LA AF Haschke, JM Allen, TH Morales, LA TI Reactions of plutonium dioxide with water and hydrogen-oxygen mixtures: Mechanisms for corrosion of uranium and plutonium SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE uranium; plutonium; corrosion mechanism; higher oxide; catalysis ID ENVIRONMENTAL DISPERSAL; OXIDATION; VAPOR; KINETICS; AIR; CONSEQUENCES AB Investigation shows that plutonium dioxide interacts chemically with water and catalytically with oxygen-hydrogen mixtures to form water. Water adsorbs strongly on the oxide below 120 degreesC and desorbs as the temperature is increased to 200 degreesC. Hydroxide formed by dissociative adsorption of water promotes formation of the higher oxide (PuO2+x) plus H-2, and in the presence of O-2, drives a water-catalyzed cycle that accelerates formation of PuO2+x by the PuO2 + O-2 reaction. Results are consistent with kinetic control of plutonium corrosion by the adherent oxide layer on the metal and imply that moisture-enhanced oxidation is driven by the water-catalyzed cycle. Evaluation of experimental results and literature data for U and Pu lead to a comprehensive corrosion mechanism applicable to both metals in dry air. water vapor, and moist air. In all cases, corrosion proceeds by diffusion of oxide ions through the oxide product, not by transport of hydrogen or hydroxide. Rates vary as changes in the concentration of adsorbed water determine the rate of O2- formation and the gradient in oxygen concentration across the oxide diffusion barrier. Results account for a sharp decrease in the corrosion rate of Pu by water and moist air as the temperature approaches 200 degreesC. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Kaiser Hill Co LLC, Golden, CO 80402 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Haschke, JM (reprint author), 11003 Willow Bend Dr, Waco, TX 76712 USA. NR 46 TC 37 Z9 38 U1 4 U2 46 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 16 PY 2001 VL 314 IS 1-2 BP 78 EP 91 DI 10.1016/S0925-8388(00)01222-6 PG 14 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 393FT UT WOS:000166459100012 ER PT J AU Aponte, JL Sega, GA Hauser, LJ Dhar, MS Withrow, CM Carpenter, DA Rinchik, EM Culiat, CT Johnson, DK AF Aponte, JL Sega, GA Hauser, LJ Dhar, MS Withrow, CM Carpenter, DA Rinchik, EM Culiat, CT Johnson, DK TI Point mutations in the murine fumarylacetoacetate hydrolase gene: Animal models for the human genetic disorder hereditary tyrosinemia type 1 SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID ALBINO-DELETION COMPLEX; MISSENSE MUTATION; SUCCINYLACETONE; MOUSE; LOCUS; IDENTIFICATION; PATIENT; REGION; LIVER; MICE AB Hereditary tyrosinemia type 1 (HT1) is a severe autosomal recessive metabolic disease associated with point mutations in the human fumarylacetoacetate hydrolase (FAH) gene that disrupt tyrosine catabolism. An acute form of HT1 results in death during the first months of life because of hepatic failure, whereas a chronic form leads to gradual development of liver disease often accompanied by renal dysfunction, childhood rickets, neurological crisis, and hepatocellular carcinoma. Mice homozygous for certain chromosome 7 deletions of the albino Tyr; c locus that also include Fah die perinatally as a result of liver dysfunction and exhibit a complex syndrome characterized by structural abnormalities and alterations in gene expression in the liver and kidney. Here we report that two independent, postnatally lethal mutations induced by N-ethyl-N-nitrosourea and mapped near Tyr are alleles of Fah. The Fah(6287SB) allele is a missense mutation in exon 6, and Fah(5961SB) is a splice mutation causing loss of exon 7, a subsequent frameshift in the resulting mRNA, and a severe reduction of Fah mRNA levels. increased levels of the diagnostic metabolite succinylacetone in the urine of the Fah(6287SB) and Fah(5961SB) mutants indicate that these mutations cause a decrease in Fah enzymatic activity. Thus, the neonatal phenotype present in both mutants is due to a deficiency in Fah caused by a point mutation, and we propose Fah(5961SB) and Fah(6287SB) as mouse models for acute and chronic forms of human HT1, respectively. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Div Biol, Knoxville, TN 37996 USA. RP Johnson, DK (reprint author), Oak Ridge Natl Lab, Div Life Sci, POB 2009, Oak Ridge, TN 37831 USA. RI Hauser, Loren/H-3881-2012 NR 40 TC 25 Z9 28 U1 1 U2 1 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD JAN 16 PY 2001 VL 98 IS 2 BP 641 EP 645 DI 10.1073/pnas.98.2.641 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 393TG UT WOS:000166485300053 PM 11209059 ER PT J AU Groenewold, GS Kessinger, GF Scott, JR Gianotto, AK Appelhans, AD Delmore, JE Avci, R AF Groenewold, GS Kessinger, GF Scott, JR Gianotto, AK Appelhans, AD Delmore, JE Avci, R TI Secondary ion mass spectrometry of zeolite materials: Observation of abundant aluminosilicate oligomers using an ion trap SO ANALYTICAL CHEMISTRY LA English DT Article ID ANALYSIS LAMMA; AEROSOL-PARTICLES; SURFACES; CATIONS; SILICA; SIMS; CLUSTERS; NITRATE; ANIONS AB Oligomeric oxyanions were observed in the secondary ion mass spectra (SIMS) of zeolite materials. The oxyanions have the general composition AlmSinO2(m+n)H(m-1)- (m + n = 2 to 8) and are termed dehydrates. For a given mass, multiple elemental compositions are possible because (Al + H) is an isovalent and isobaric substitute for Si. Using 18 keV Ga+ as a projectile, oligomer abundances are low relative to the monomers. Oligomer abundance can be increased by using the polyatomic projectile ReO4- (similar to5 keV). Oligomer abundance can be further increased using an ion trap (IT-) SIMS; in this instrument, long ion lifetimes (tens of ms) and relatively high He pressure result in significant collisional stabilization and increased high-mass abundance. The dehydrates rapidly react with adventitious H2O present in the IT-SIMS to form mono-, di-, and trihydrates. The rapidity of the reaction and comparison to aluminum oxyanion hydration suggest that H2O adds to the aluminosilicate oxyanions in a dissociative fashion, forming covalently bound product ions. In addition to these findings, it was noted that production of abundant oligomeric aluminosilicates could be significantly increased by substituting the countercation (NH4+) with the larger alkali ions Rb+ and Cs+. This constitutes a useful tactic for generating large aluminosilicate oligomers for surface characterization and ion-molecule reactivity studies. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. Montana State Univ, Dept Phys, Image & Chem Anal Lab, Bozeman, MT 59717 USA. RP Groenewold, GS (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. RI Scott, Jill/G-7275-2012 NR 41 TC 12 Z9 12 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 JAN 15 PY 2001 VL 73 IS 2 BP 226 EP 232 DI 10.1021/ac000742a PG 7 WC Chemistry, Analytical SC Chemistry GA 391QE UT WOS:000166366000013 PM 11199970 ER PT J AU Belov, ME Nikolaev, EN Anderson, GA Udseth, HR Conrads, TP Veenstra, TD Masselon, CD Gorshkov, MV Smith, RD AF Belov, ME Nikolaev, EN Anderson, GA Udseth, HR Conrads, TP Veenstra, TD Masselon, CD Gorshkov, MV Smith, RD TI Design and performance of an ESI interface for selective external ion accumulation coupled to a Fourier transform ion cyclotron mass spectrometer SO ANALYTICAL CHEMISTRY LA English DT Article ID PROTEIN AB The coupling of Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) with electrospray ionization has advanced the analysis of large biopolymers and provided the basis for high-throughput protein characterization (e.g,, for rapid "proteome" analyses). In this work, the combination of high-performance capillary liquid chromatography with FTICR mass spectrometry and external ion accumulation has been shown to increase both sensitivity and analysis duty cycle. Instrument versatility is further improved by ion preselection followed by ion accumulation in an external linear quadrupole ion trap. The interface was tested with a 3.5-T FTICR mass spectrometer and evaluated with a number of peptides and proteins whose molecular weights ranged from 500 to 66 000. A significant increase in the sensitivity, duty cycle, and dynamic range over that of the previously used accumulated trapping was achieved, exhibiting a detection limit of similar to 10 zmol (similar to 6000 molecules) for smaller proteins such as cytochrome c. Capillary LC external accumulation interface with FTICR was successfully applied for the study of whole-proteome mouse tryptic digests. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Russian Acad Sci, Inst Chem Phys Energy Problems, Moscow 117829, Russia. RP Belov, ME (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Gorshkov, Mikhail/E-8522-2010; Masselon, Christophe/A-2340-2010; Smith, Richard/J-3664-2012; Nikolaev, Eugene/N-4498-2013; Gorshkov, Mikhail/N-4984-2013 OI Smith, Richard/0000-0002-2381-2349; Nikolaev, Eugene/0000-0001-6209-2068; Gorshkov, Mikhail/0000-0001-9572-3452 FU NCRR NIH HHS [RR12365] NR 28 TC 79 Z9 81 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JAN 15 PY 2001 VL 73 IS 2 BP 253 EP 261 DI 10.1021/ac000633w PG 9 WC Chemistry, Analytical SC Chemistry GA 391QE UT WOS:000166366000017 PM 11199974 ER PT J AU Griffiths, SK Nilson, RH AF Griffiths, SK Nilson, RH TI Low dispersion turns and junctions for microchannel systems SO ANALYTICAL CHEMISTRY LA English DT Article ID MICELLAR ELECTROKINETIC CHROMATOGRAPHY; OPEN-CHANNEL ELECTROCHROMATOGRAPHY; CAPILLARY LIQUID-CHROMATOGRAPHY; ELECTROPHORETIC ANALYSIS; ELECTROOSMOTIC FLOW; SEPARATIONS; CHIPS; DNA; GLASS; MICROCHIPS AB Numerical methods are employed to optimize the geometry of two-dimensional microchannel turns such that the turn-induced spreading of a solute band is minimized. An inverted numerical method is first developed to compute the electric potential and local species motion in turns of arbitrary geometry. The turn geometry is then optimized by means of a nonlinear least-squares minimization algorithm using the spatial variance of the species distribution leaving the turn as the object function. This approach yields the turn geometry producing the minimum possible dispersion, subject only to prescribed constraints. The resulting low-dispersion turns provide an induced variance 2-3 orders of magnitude below that of a comparable conventional turns. Sample results are presented for 180 and 90 degrees turns, and the use of these turns to form wyes and tees is discussed. A sample 45 degrees wye is presented. The use of low-dispersion turns in folding separation columns is also discussed, and sample calculations are presented for folding a column 100 mum in width and up to 900 mm in length onto a region of only 10 by 10 mm. These low-dispersion geometries are applicable to electroosmosis, electrophoresis, and some pressure-driven flows. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Griffiths, SK (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 40 TC 100 Z9 103 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 JAN 15 PY 2001 VL 73 IS 2 BP 272 EP 278 DI 10.1021/ac000936q PG 7 WC Chemistry, Analytical SC Chemistry GA 391QE UT WOS:000166366000020 PM 11199977 ER PT J AU Jin, Z Su, YX Duan, YX AF Jin, Z Su, YX Duan, YX TI A low power, atmospheric pressure, pulsed plasma source for molecular emission spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID GAS-CHROMATOGRAPHY; DETECTOR AB A low-power, plasma source-based, portable molecular emission detector is described in this paper, The detector employs a pulsed-plasma source operated at atmospheric pressure for molecular fragmentation and excitation. The plasma was generated with a home-built high-voltage pulsed power supply. The average operational power of the detector was less than 0.2 W. The effects of operational parameters such as plasma gas, voltage, and plasma gas now rate were investigated. Molecular emission spectra of a variety of organic compounds were studied, The features of the emission spectra obtained with the pulsed plasma source were significantly different from those obtained with direct current (dc) discharge at a power higher than 10 W. The spectra obtained in this work showed strong CH emission at 431.2 nm; however, the typical CN emission observed with a conventional de plasma source at 383-388 nm was very weak in most cases. The strong CN emission was only obtained for compounds containing nitrogen, such as aniline. Dimethyl sulfoxide can be detected at a limit of 200 ppb using helium plasma by observing the emission band of the CH radical. The detector was very stable and did not experience electrode fouling even with the introduction of organic vapors. Such a detector is very promising for organic vapor detection. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Duan, YX (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, CST-9,MS K484, Los Alamos, NM 87545 USA. NR 18 TC 37 Z9 37 U1 3 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JAN 15 PY 2001 VL 73 IS 2 BP 360 EP 365 DI 10.1021/ac000678x PG 6 WC Chemistry, Analytical SC Chemistry GA 391QE UT WOS:000166366000033 PM 11199990 ER PT J AU Temelkuran, B Bayindir, M Ozbay, E Kavanaugh, JP Sigalas, MM Tuttle, G AF Temelkuran, B Bayindir, M Ozbay, E Kavanaugh, JP Sigalas, MM Tuttle, G TI Quasimetallic silicon micromachined photonic crystals SO APPLIED PHYSICS LETTERS LA English DT Article ID LOW-FREQUENCY PLASMONS; BAND-GAP; STOP BANDS AB We report on fabrication of a layer-by-layer photonic crystal using highly doped silicon wafers processed by semiconductor micromachining techniques. The crystals, built using (100) silicon wafers, resulted in an upper stop band edge at 100 GHz. The transmission and defect characteristics of these structures were found to be analogous to metallic photonic crystals. We also investigated the effect of doping concentration on the defect characteristics. The experimental results agree well with predictions of the transfer matrix method simulations. (C) 2001 American Institute of Physics. C1 Bilkent Univ, Dept Phys, TR-06533 Ankara, Turkey. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Microelect Res Ctr, Ames, IA 50011 USA. RP Temelkuran, B (reprint author), Bilkent Univ, Dept Phys, TR-06533 Ankara, Turkey. RI Ozbay, Ekmel/B-9495-2008 NR 21 TC 26 Z9 26 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 15 PY 2001 VL 78 IS 3 BP 264 EP 266 DI 10.1063/1.1339256 PG 3 WC Physics, Applied SC Physics GA 389YY UT WOS:000166267300002 ER PT J AU Campbell, IH Smith, DL Neef, CJ Ferraris, JP AF Campbell, IH Smith, DL Neef, CJ Ferraris, JP TI Optical properties of single carrier polymer diodes under high electrical injection SO APPLIED PHYSICS LETTERS LA English DT Article ID LIGHT-EMITTING-DIODES; EXCITATION; CHARGE; TRANSPORT; LASERS AB We present measurements of the modulation of the near absorption edge optical properties of single carrier diodes made from a soluble poly(p-phenylene vinylene) derivative. Pulsed electrical excitation was used to acquire the optical characteristics for average injected charge densities up to 10(18) cm(-3). For injected carrier densities below 5x10(17) cm(-3), the modulation of the optical properties are dominated by electroabsorption effects; at higher densities, the effects of the injected charge predominate. We find that there is no significant absorption by the injected charge below the optical absorption threshold and that there is substantial bleaching of the lowest energy optical transitions at high carrier density. These results imply that charge carrier absorption in this polymer does not limit the performance of organic light-emitting diodes and diode lasers. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Texas, Richardson, TX 75083 USA. RP Campbell, IH (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 13 Z9 13 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 15 PY 2001 VL 78 IS 3 BP 270 EP 272 DI 10.1063/1.1340859 PG 3 WC Physics, Applied SC Physics GA 389YY UT WOS:000166267300004 ER PT J AU Burns, AR Carpick, RW AF Burns, AR Carpick, RW TI Directional shear force microscopy SO APPLIED PHYSICS LETTERS LA English DT Article ID SCANNING OPTICAL MICROSCOPE; FRICTION ANISOTROPY; DISTANCE CONTROL; MONOLAYER AB We describe a technique, based on shear force microscopy, that allows one to detect shear forces in a chosen direction at the nanometer scale. The lateral direction of an oscillating probe tip is determined by selecting which of the four quadrants are excited on the piezo driver. The shear forces depend directly on this lateral direction if structural anisotropies are present, as confirmed with polydiacetylene monolayers. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Burns, AR (reprint author), Sandia Natl Labs, MS 1413, Albuquerque, NM 87185 USA. NR 17 TC 7 Z9 7 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 15 PY 2001 VL 78 IS 3 BP 317 EP 319 DI 10.1063/1.1341225 PG 3 WC Physics, Applied SC Physics GA 389YY UT WOS:000166267300020 ER PT J AU Fang, ZQ Look, DC Jasinski, J Benamara, M Liliental-Weber, Z Molnar, RJ AF Fang, ZQ Look, DC Jasinski, J Benamara, M Liliental-Weber, Z Molnar, RJ TI Evolution of deep centers in GaN grown by hydride vapor phase epitaxy SO APPLIED PHYSICS LETTERS LA English DT Article ID STOICHIOMETRY; DISLOCATION AB Deep centers and dislocation densities in undoped n GaN, grown by hydride vapor phase epitaxy (HVPE), were characterized as a function of the layer thickness by deep level transient spectroscopy and transmission electron microscopy, respectively. As the layer thickness decreases, the variety and concentration of deep centers increase, in conjunction with the increase of dislocation density. Based on comparison with electron-irradiation induced centers, some dominant centers in HVPE GaN are identified as possible point defects. (C) 2001 American Institute of Physics. C1 Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Lincoln Lab, Lexington, MA 02173 USA. USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Fang, ZQ (reprint author), Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 15 TC 81 Z9 81 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 15 PY 2001 VL 78 IS 3 BP 332 EP 334 DI 10.1063/1.1338970 PG 3 WC Physics, Applied SC Physics GA 389YY UT WOS:000166267300025 ER PT J AU Yoon, J Clarke, J Gildemeister, JM Lee, AT Myers, MJ Richards, PL Skidmore, JT AF Yoon, J Clarke, J Gildemeister, JM Lee, AT Myers, MJ Richards, PL Skidmore, JT TI Single superconducting quantum interference device multiplexer for arrays of low-temperature sensors SO APPLIED PHYSICS LETTERS LA English DT Article ID STRONG ELECTROTHERMAL FEEDBACK; TRANSITION EDGE SENSORS; BOLOMETER AB We present the design and experimental evaluation of a superconducting quantum interference device (SQUID) multiplexer for an array of low-temperature sensors. Each sensor is inductively coupled to a superconducting summing loop which, in turn, is inductively coupled to the readout SQUID. The flux-locked loop of the SQUID is used to null the current in the summing loop and thus cancel crosstalk. The sensors are biased with an alternating current, each with a separate frequency, and the individual sensor signals are separated by lock-in detection at the SQUID output. We have fabricated a prototype 8 channel multiplexer and discuss the application to a larger array. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RP Yoon, J (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 12 TC 84 Z9 84 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 15 PY 2001 VL 78 IS 3 BP 371 EP 373 DI 10.1063/1.1338963 PG 3 WC Physics, Applied SC Physics GA 389YY UT WOS:000166267300038 ER PT J AU Oh, SJ Kim, W Kim, W Choi, BH Kim, JY Koh, H Kim, HJ Park, JH AF Oh, SJ Kim, W Kim, W Choi, BH Kim, JY Koh, H Kim, HJ Park, JH TI Geometric and magnetic propel-ties of Co/Pd system SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 1st Vacuum and Surface Science Conference of Asia and Australia CY SEP 08-10, 1999 CL TOKYO, JAPAN DE dichroism; magnetic anisotropy; rough interface; hybridization ID X-RAY-DICHROISM; MAGNETOCRYSTALLINE ANISOTROPY; CIRCULAR-DICHROISM; ORBITAL MAGNETISM; ULTRATHIN FILMS; COBALT FILMS; THIN-FILMS; CO; MULTILAYERS; MOMENT AB We measured geometric and magnetic properties of Co films on the Pd(1 1 1) surface by X-ray photoelectron diffraction (XPD), X-ray magnetic circular dichroism (MCD) at the Co L-2,L-3 edge, and the surface magneto-optical Kerr effect (SMOKE) measurements. Co thin films are found to grow incoherently with fee island structure on the smooth Pd(1 1 1) substrate. Comparison of MCD and SMOKE measurements of Co thin films grown on rough and smooth Pd(1 1 1) surfaces suggests that perpendicular remnant magnetization and Co orbital moment are enhanced by the rough interface. Pd capping layer also induces perpendicular orbital moment enhancement. These observations indicate the influence of hybridization between Co 3d and Pd 4d at the interface on the magnetic anisotropy. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Oh, SJ (reprint author), Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. NR 25 TC 13 Z9 13 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD JAN 15 PY 2001 VL 169 BP 127 EP 133 DI 10.1016/S0169-4332(00)00735-2 PG 7 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 404FX UT WOS:000167087700026 ER PT J AU Bader-Meunier, B Gauthier, F Archambaud, F Cynober, T Mielot, F Dommergues, JP Warszawski, J Mohandas, N Tchernia, G AF Bader-Meunier, B Gauthier, F Archambaud, F Cynober, T Mielot, F Dommergues, JP Warszawski, J Mohandas, N Tchernia, G TI Long-term evaluation of the beneficial effect of subtotal splenectomy for management of hereditary spherocytosis SO BLOOD LA English DT Article ID POSTSPLENECTOMY SEPSIS; SPLENIC TISSUE; INFECTION; SPLEEN; MORTALITY; FAILURE AB Clinical manifestations of hereditary spherocytosis (HS) can be abrogated by splenectomy, However, concerns exist regarding exposure of patients to a lifelong risk for overwhelming infections and, to a lesser extent, to vascular complications after total splenectomy, In the search for alternative treatment modalities, we assessed, in a previous pilot study, the potential usefulness of subtotal splenectomy in a small population of patients. During a mean follow-up period of 3.5 years, subtotal splenectomy was shown to be effective in decreasing the hemolytic rate, while maintaining the phagocytic function of the spleen. In the current study, we evaluated the clinical and biologic features of 40 patients with HS who underwent subtotal splenectomy and were monitored for periods ranging from 1 to 14 years. The beneficial effect of subtotal splenectomy included a sustained decrease in hemolytic rate and a continued maintenance of phagocytic function of the splenic remnant. However, mild-to-moderate hemolysis was persistent and accounted for secondary gallstone formation and aplastic crisis in a small subset of patients. Surprisingly, regrowth of the remnant spleen did not seem to have a major impact on the beneficial outcomes of these individuals. Our results suggest that subtotal splenectomy appears to be a reasonable treatment option for management of patients with HS, especially young children. (C) 2001 by The American Society of Hematology. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. Hop Paris, Fac Med Paris 11, Paris, France. Hop Bicetre, INSERM, Dept Pediat,U292, Lab Hematol,Serv Med Nucl,Serv Epidemiol & Stat, Le Kremlin Bicetre, France. RP Mohandas, N (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Mailstop 74-157,1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NIDDK NIH HHS [DK26263] NR 32 TC 68 Z9 76 U1 0 U2 6 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 JAN 15 PY 2001 VL 97 IS 2 BP 399 EP 403 DI 10.1182/blood.V97.2.399 PG 5 WC Hematology SC Hematology GA 392AG UT WOS:000166388000010 PM 11154215 ER PT J AU Wandersee, NJ Roesch, AN Hamblen, NR de Moes, J van der Valk, MA Bronson, RT Gimm, JA Mohandas, N Demant, P Barker, JE AF Wandersee, NJ Roesch, AN Hamblen, NR de Moes, J van der Valk, MA Bronson, RT Gimm, JA Mohandas, N Demant, P Barker, JE TI Defective spectrin integrity and neonatal thrombosis in the first mouse model for severe hereditary elliptocytosis SO BLOOD LA English DT Article ID RECOMBINANT CONGENIC STRAINS; TETRAMER BINDING-SITE; HEMOLYTIC-ANEMIA; MESSENGER-RNA; NUCLEOTIDE-SEQUENCE; GENETIC COMPOSITION; MUTATION; MICE; SPHEROCYTOSIS; MEMBRANE AB Mutations affecting the conversion of spectrin dimers to tetramers result in hereditary elliptocytosis (HE), whereas a deficiency of human erythroid alpha- or beta -spectrin results in hereditary spherocytosis (HS), All spontaneous mutant mice with cytoskeletal deficiencies of spectrin reported to date have HS, Here, the first spontaneous mouse mutant, sph(Dem)/sph(Dem), With Severe HE is described. The sph(Dem) mutation is the insertion of an intracisternal A particle element in intron in of the erythroid alpha -spectrin gene. This causes exon skipping, the in-frame deletion of 46 amino acids from repeat 5 of alpha -spectrin and alters spectrin dimer/tetramer stability and osmotic fragility. The disease is more severe in sphDem/sphDem neonates than in alpha -spectrin-deficient mice with HS, Thrombosis and infarction are not, as in the HS mice, limited to adults but occur soon after birth. Genetic background differences that exist between HE and HS mice are suspect, along with red blood cell morphology differences, as modifiers of thrombosis timing. sph(Dem)/sph(Dem) mice provide a unique model for analyzing spectrin dimer-to-tetramer conversion and identifying factors that influence thrombosis. (C) 2001 by The American Society of Hematology. C1 Jackson Lab, Bar Harbor, ME 04609 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Netherlands Canc Inst, Div Mol Genet, NL-1066 CX Amsterdam, Netherlands. Tufts Univ, Sch Vet Med, Boston, MA 02111 USA. RP Barker, JE (reprint author), Jackson Lab, 600 Main St, Bar Harbor, ME 04609 USA. FU NHLBI NIH HHS [R01 HL29305]; NIDDK NIH HHS [F32 DK09482, R01 DK26263] NR 43 TC 15 Z9 15 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 JAN 15 PY 2001 VL 97 IS 2 BP 543 EP 550 DI 10.1182/blood.V97.2.543 PG 8 WC Hematology SC Hematology GA 392AG UT WOS:000166388000030 PM 11154235 ER PT J AU Doskey, PV AF Doskey, PV TI Spatial variations and chronologies of aliphatic hydrocarbons in Lake Michigan sediments SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; MARINE BENTHIC ALGAE; ORGANIC-MATTER; ATMOSPHERIC DEPOSITION; PARTICULATE MATTER; SOUTHERN BASIN; NORMAL-ALKANES; PUGET-SOUND; WASHINGTON; TRANSPORT AB Four sediment cores were collected in fine-grained depositional areas of the southern basin of Lake Michigan. Spatial variations of aliphatic hydrocarbons in surficial sediments were consistent with a lakeward movement of riverine sediments in a series of resuspension-settling cycles in which an unresolved complex mixture (UCM) of hydrocarbons associated with dense sediments is deposited in nearshore areas, fine-grained sediments of terrestrial origin accumulate in the deep basin, and planktonic hydrocarbons are depleted by microbial degradation during transport to the deep basin;The rate of accumulation of the,UCM (a marker of petroleum residues) in deep. basin sediments has increased by more than an order of magnitude since 1880, from 60 mug m(-2).a(-1) to approximately 960 mug m(-2).a(-1) in 1980. Crude estimates of the atmospheric loading of the UCM (1100 mug m(-2).a(-1)) indicate that accumulations in deep-basin sediments might be supported by atmospheric deposition. Agreement was poor between the atmospheric flux of the terrestrial n-alkanes (SigmaC(25), C-27, C-29, C-31) to the deep basin (3200 mug m(-2).a(-1)) and the sediment accumulation rate (660 mug m(-2).a(-1)). Understanding of atmospheric fluxes, estimated from the Very few available data, would be improved by more frequent measurement of the levels of aliphatic hydrocarbons in air and precipitation and a better knowledge of the particle deposition velocities and precipitation scavenging coefficients. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Doskey, PV (reprint author), Argonne Natl Lab, Div Environm Res, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 65 TC 20 Z9 21 U1 4 U2 12 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 JAN 15 PY 2001 VL 35 IS 2 BP 247 EP 254 DI 10.1021/es001365m PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 392BL UT WOS:000166390700001 PM 11347594 ER PT J AU Bench, G Carlsen, TM Grant, PG Wollett, JS Martinelli, RE Lewis, JL Divine, KK AF Bench, G Carlsen, TM Grant, PG Wollett, JS Martinelli, RE Lewis, JL Divine, KK TI Olfactory bulb uptake and determination of biotransfer factors in the California ground squirrel (Spermophilus beecheyi) exposed to manganese and cadmium in environmental habitats SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID ECOLOGICAL RISK-ASSESSMENT; RAT-BRAIN; TRANSPORT; EPITHELIUM; PATHWAYS; LESSONS; SYSTEM AB Manganese (Mn) and cadmium (Cd) profiles in olfactory bulbs of California ground squirrels (Spermophilus beecheyi) trapped at Lawrence Livermore National Laboratory's Site 300 facility in California were determined with proton induced X-ray emission (PIXE). As a reference, Mn profiles in olfactory bulbs from laboratory rats exposed via nose-only inhalation to 0.53 mg/m(3) Mn in the form of MnCl2 were also determined with PIXE. Atomic absorption spectrophotometry was used to measure soil Mn and Cd contents from the trapping sites and Mn and Cd contents in ground squirrel liver and leg muscle tissues. The data from laboratory rats revealed that Mn uptake into the olfactory bulb occurs via inhalation exposure. Data from ground squirrels and knowledge of the collection sites indicate that although several routes of exposure may occur, fossorial rodent olfactory uptake affords a significant exposure route to Mn and Cd in soils. Measured biotransfer factors (ratio of leg muscle tissue metal content to soil metal content) for Cd in ground squirrels were 10(3)-fold greater than exposure modeling estimates based on oral Cd uptake data from livestock. The measurements for ground squirrel tissues show that when conducting ecological risk assessments for natural habitats considerable care should be taken in selecting transfer factors. Specifically, transfer factors derived from data pertaining to comparable exposure pathways and ecological setting should be used wherever possible. C1 Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. Univ New Mexico, Ctr Populat Hlth, Albuquerque, NM 87131 USA. Lovelave Resp Res Inst, Albuquerque, NM 87185 USA. RP Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, L-397,POB 808, Livermore, CA 94550 USA. EM bench1@llnl.gov NR 42 TC 14 Z9 15 U1 2 U2 7 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 JAN 15 PY 2001 VL 35 IS 2 BP 270 EP 277 DI 10.1021/es0014180 PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 392BL UT WOS:000166390700004 PM 11347597 ER PT J AU Sokolov, I Smith, DS Henderson, GS Gorby, YA Ferris, FG AF Sokolov, I Smith, DS Henderson, GS Gorby, YA Ferris, FG TI Cell surface electrochemical heterogeneity of the Fe(III)-reducing bacteria Shewanella putrefaciens SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CRYSTALLINE IRON(III) OXIDES; ATOMIC-FORCE MICROSCOPE; IRON-REDUCING BACTERIUM; MICROBIAL REDUCTION; DISSIMILATORY REDUCTION; STRUCTURAL FE(III); MEMBRANE-VESICLES; CHEMISTRY; DISCRETE; SMECTITE AB Acid-base titration experiments and electrostatic force microscopy (EFM) were used to investigate the cell surface electrochemical heterogeneity of the Fe(III)-reducing bacteria, Shewanella putrefaciens. The acid-base titrations extended from pH 4 to 10; and the titration data were fit using a linear programming pK(a) spectrum approach. Overall, a five-site model ac-counted for the observed titration behavior with the most acidic sites corresponding to carboxylic groups and phosphodiester groups, intermediate: sites phosphoryl groups, and two basic sites equivalent to amine or hydroxyl groups. The pH for the point of zero charge on the bacteria was 5.4. In EFM images bf cells rinsed in solutions at pH 4.0, 7.0, and 8.0, a pronounced increase in small (less than or equal to 100 nm diameter) high contrast patches was observed on the cells with increasing pH. The pH dependence of EFM image contrast paralleled the pattern of cell surface charge development inferred from the titration experiments; however, quantitative; analysis of high Contrast regions in the EFM images yielded lower surface charge values than those anticipated from the titration data. For example at pH 7, the calculated surface; charge of high contrast regions in EFM images of the bacterial cells was -0.23 muC/cm(2) versus -20.0 muC/cm(2) based on the titration curve. The differences in surface charge estimates,between the EFM images and titration data are consistent not only with charge development throughout the entire-volume of the bacterial cell wall (i.e., in association with functional groups that are not directly exposed at the cell surface) but also with the presence of a thin structural layer of water containing charge-compensating counterions. In combination, the pK(a) spectra and EFM data demonstrate that a particularly high degree of electrochemical heterogeneity exists within the cell wall and at the cell surface of S. putrefaciens. C1 Univ Toronto, Dept Geol, Toronto, ON M5S 3B1, Canada. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Ferris, FG (reprint author), Univ Toronto, Dept Geol, 22 Russell St, Toronto, ON M5S 3B1, Canada. RI Smith, D. Scott/I-6004-2012; Sokolov, Igor/A-6858-2009 OI Smith, D. Scott/0000-0002-3075-4087; Sokolov, Igor/0000-0001-6260-4326 NR 38 TC 106 Z9 108 U1 2 U2 22 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 JAN 15 PY 2001 VL 35 IS 2 BP 341 EP 347 DI 10.1021/es001258s PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 392BL UT WOS:000166390700014 PM 11347607 ER PT J AU Spalding, BP Spalding, IR AF Spalding, BP Spalding, IR TI Chemical equilibria model of strontium-90 adsorption and transport in soil in response to dynamic alkaline conditions SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID SOLUTE TRANSPORT; VARIABLE PH; RADIONUCLIDE AB Strontium-90 is a major hazardous contaminant of radioactive wastewater and its processing sludges at many Department of Energy (DOE) facilities. In the past, such contaminated wastewater and sludge have been disposed in soil seepage pits, lagoons, or cribs often under highly perturbed alkaline conditions (pH > 12) where (90) Sr solubility is low and its adsorption to surrounding soil is high. As, natural weathering returns these soils to near-neutral or slightly acidic conditions, the adsorbed and precipitated calcium and magnesium phases, in which (90)- Sr is carried,:change significantly in both,nature and amounts. No comprehensive computational method has been formulated previously to quantitatively simulate the dynamics of Sr-90 in the:soil-groundwater environment under such dynamic and wide-ranging Conditions. A computational code; the Hydrologic Utility Model for Demonstrating Integrated Nuclear Geochemical Environmental Responses (HUMDINGER), was composed to describe the changing equilibria of Sr-90 in soil based bn its causative chemical reactions including soil buffering, pH-dependent cation-exchange capacity, cation selectivity, and the precipitation/dissolution of calcium carbonate, calcium hydroxide, and magnesium hydroxide in response to leaching groundwater characteristics including pH, acid-neutralizing capacity, dissolved cations, and inorganic carbonate species. The code includes a simulation of one-dimensional transport of 90Sr through a soil column as a series of soil mixing cells where the equilibrium soluble output from one cell is applied to the next cell. Unamended soil leaching and highly alkaline soil treatments, including potassium hydroxide, sodium silicate, and sodium aluminate, were simulated and compared with experimental findings using large (10 kg)-soil columns that were leached with Sr-90-contaminated groundwater after treatment. HUMDINGER's simulations were in good agreement with dynamic experimental observations of soil exchange capacity, exchangeable cations, total Sr-90, and pH values of layers within the-soil columns and of column effluents. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Spalding, BP (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2006, Oak Ridge, TN 37831 USA. NR 32 TC 13 Z9 13 U1 1 U2 15 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 JAN 15 PY 2001 VL 35 IS 2 BP 365 EP 373 DI 10.1021/es001445q PG 9 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 392BL UT WOS:000166390700018 PM 11347611 ER PT J AU Morrison, SJ Metzler, DR Carpenter, CE AF Morrison, SJ Metzler, DR Carpenter, CE TI Uranium precipitation in a permeable reactive barrier by progressive irreversible dissolution of zerovalent iron SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID ZERO-VALENT IRON; REMEDIATION; GROUNDWATER; ADSORPTION; REMOVAL AB A permeable reactive barrier (PRB) containing zerovalent iron-[Fe(0)] was installed at a former uranium milling site in Monticello, UT. A large-scale column experiment was conducted at the site to test the feasibility of Fe(0) to treat U prior to installing the PRB. Effluents from the field column experiment had pH values near 7.34, moderate decreases in C(IV) and Ca concentrations, and an elevated Fe concentration (27.1 mg/L). In contrast, groundwater exiting the PRE had a pH value of 9.82, decreases in C(IV) and Ca concentrations, and a low concentration of Fe (0.17 mg/L). A geochemical mode was used to explain the chemical changes that occurred in both the field column experiment and the PRB. The model simulated the systems by the progressive irreversible dissolution of Fe(0). Modeling results indicated that a longer residence time in the PRB compared with the shorter residence time, in the column contributed to the disparate effluent qualities. Prior to modeling, a controlled laboratory column experiment was conducted to help evaluate the,dominant chemical mechanisms by which Fe(0) removes U-from aqueous solutions. Results of the laboratory column experiment indicated that only a small amount of U could be adsorbed to-ferric minerals, and, therefore, this mechanism was not considered in the model. C1 Environm Sci Lab, Grand Junction, CO 81503 USA. US DOE, Grand Junct Off, Grand Junction, CO 81503 USA. RP Morrison, SJ (reprint author), Environm Sci Lab, 2597 B3-4 Rd, Grand Junction, CO 81503 USA. NR 17 TC 73 Z9 74 U1 6 U2 31 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 JAN 15 PY 2001 VL 35 IS 2 BP 385 EP 390 DI 10.1021/es001204i PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 392BL UT WOS:000166390700021 PM 11347614 ER PT J AU Johnson, JR Cheng, CZ Song, P AF Johnson, JR Cheng, CZ Song, P TI Signatures of mode conversion and kinetic Alfven waves at the magnetopause SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RESONANT AMPLIFICATION; SUBSOLAR MAGNETOPAUSE; DAYSIDE MAGNETOPAUSE; PLASMA TRANSPORT; BOUNDARY-LAYER; MAGNETIC SHEAR; MAGNETOSHEATH AB It has been suggested that resonant mode conversion of compressional MHD waves into kinetic Alfven waves at the magnetopause can explain the abrupt transition in wave polarization from compressional to transverse commonly observed during magnetopause crossings [Johnson and Cheng, 1997b]. We analyze magnetic field data for magnetopause crossings as a function of magnetic shear angle (defined as the angle between the magnetic fields in the magnetosheath and magnetosphere) and compare with the theory of resonant mode conversion. The data suggest that amplification in the transverse magnetic field component at the magnetopause is not significant up to a threshold magnetic shear angle. Above the threshold angle significant amplification results but with weak dependence on magnetic shear angle. Waves with higher frequency are less amplified and have a higher threshold angle. These observations are qualitatively consistent with theoretical results obtained from the kinetic-fluid wave equations. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Michigan, Space Phys Res Lab, Ann Arbor, MI 48109 USA. RP Johnson, JR (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Cheng, Chio/K-1005-2014 NR 13 TC 45 Z9 45 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2001 VL 28 IS 2 BP 227 EP 230 DI 10.1029/2000GL012048 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 392MN UT WOS:000166415400008 ER PT J AU Sun, DZ Covey, C Lindzen, RS AF Sun, DZ Covey, C Lindzen, RS TI Vertical correlations of water vapor in GCMs SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MODEL INTERCOMPARISON PROJECT; FEEDBACK; CLIMATE; TEMPERATURE; AMIP AB Correlations of tropical mean water vapor with its surface values have been calculated for all AMIP1 models and some of the AMIP2 models. The previously noted discrepancy between the GFDL model and rawinsonde data also exists for other models: the interannual correlations of water vapor with its surface values decline to smaller values in observations than in the models. This discrepancy is reduced somewhat after the data from the models were sampled at the same locations where observational data were collected, but remains significant even at low levels. Significant discrepancy between models and observations also exists in the regressions of water vapor on temperature, suggesting something other than differences in the noise level as the main cause for the discrepancy in the vertical correlations between model and rawinsonde observations. C1 NOAA, CIRES, OAR, CSC,RCDC1,Climate Diagnost Ctr, Boulder, CO 80305 USA. Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA USA. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA USA. RP Sun, DZ (reprint author), NOAA, CIRES, OAR, CSC,RCDC1,Climate Diagnost Ctr, 325 Broadway, Boulder, CO 80305 USA. NR 17 TC 12 Z9 13 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2001 VL 28 IS 2 BP 259 EP 262 DI 10.1029/2000GL011907 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 392MN UT WOS:000166415400016 ER PT J AU Govindasamy, B Duffy, PB Caldeira, K AF Govindasamy, B Duffy, PB Caldeira, K TI Land use Changes and Northern Hemisphere Cooling SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CLIMATE-CHANGE; AMAZON DEFORESTATION; REGIONAL CLIMATE; VEGETATION; FEEDBACKS; HOLOCENE; PATTERNS; FORESTS; MODEL AB Recent reconstructions of Northern Hemisphere mean temperatures over the past millennium show a longterm cooling of about 0.25K between 1000 and 1900 AD, prior to the 20(th) century's warming. In this paper, we present the results of equilibrium climate model simulations that indicate that the land-use change occurring over this period may largely explain this observed cooling, although other factors also could have played a significant role. The simulated annual mean cooling due to land-use change is 0.25K globally and 0.37K for the Northern Hemisphere, suggesting that the cooling of the prior centuries could have been largely the result of anthropogenic interference in the climate system. C1 Univ Calif Lawrence Livermore Natl Lab, Climate & Carbon Cycle Grp, Div Atmospher Sci, Livermore, CA 94550 USA. RP Govindasamy, B (reprint author), Univ Calif Lawrence Livermore Natl Lab, Climate & Carbon Cycle Grp, Div Atmospher Sci, 7000 E Ave,L-130, Livermore, CA 94550 USA. RI Caldeira, Ken/E-7914-2011 NR 25 TC 89 Z9 92 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2001 VL 28 IS 2 BP 291 EP 294 DI 10.1029/2000GL006121 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 392MN UT WOS:000166415400024 ER PT J AU Yang, Q Parvin, B Mariano, A AF Yang, Q Parvin, B Mariano, A TI Detection of vortices and saddle points in SST data SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GULF; RINGS; MODEL; IMAGES; EDDIES AB We extend the Horn-Schunck model of flow field computation to incorporate incompressibility for tracking fluid motion. This is expressed as a weak form of zero-divergence constraint in the variational problem and implemented with a multigrid approach for efficient computation. The resulting feature displacement velocity field provides the basis for higher level abstraction and representation of the data for data mining. A robust and efficient algorithm, based on the Jordan curve index, for detecting vortices and saddle points in feature displacement fields derived from sequences of satellite-derived SST fields is presented. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. RP Yang, Q (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 24 TC 5 Z9 5 U1 11 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2001 VL 28 IS 2 BP 331 EP 334 DI 10.1029/2000GL011408 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 392MN UT WOS:000166415400034 ER PT J AU Rodgers, A Bhattacharyya, J AF Rodgers, A Bhattacharyya, J TI Upper mantle shear and compressional velocity structure of the Central US Craton: Shear wave low-velocity zone and anisotropy SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID LEHMANN DISCONTINUITY; EARTH AB One-dimensional upper mantle velocity structure is estimated by modeling P, SV and SH body-waveforms sampling the central United States. The resulting model features a thick mantle lid with a positive velocity gradient. A significant shear wave low-velocity zone (6% velocity reduction) is required below the lid however the compressional velocities are not reduced. The paths studied lie along the fast axes of teleseismic shear wave splitting measurements and absolute plate motion. We observe splitting of upper mantle refracted shear-waves, with the transverse component slow relative to the radial component. In order to fit the shear wave arrivals and satisfy teleseismic shear-wave splitting observations we infer azimuthal anisotropy (maximum 1.6%) distributed throughout the mantle lid and low-velocity zone, with increasing anisotropy with depth. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Rodgers, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-205 Livermore, Livermore, CA 94551 USA. RI Rodgers, Arthur/E-2443-2011 NR 17 TC 7 Z9 7 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2001 VL 28 IS 2 BP 383 EP 386 DI 10.1029/2000GL012112 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 392MN UT WOS:000166415400048 ER PT J AU Clague, DS Cornelius, PJ AF Clague, DS Cornelius, PJ TI The hydrodynamic force and torque on a bounded sphere in Poiseuille flow SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS LA English DT Article DE lattice Boltzmann; pressure-driven flow; force and torque ID DISCRETIZED BOLTZMANN-EQUATION; PARTICULATE SUSPENSIONS; NUMERICAL SIMULATIONS AB The lattice Boltzmann (LB) method is used to study the hydrodynamic force and torque acting on a sphere held stationary between parallel plates in pressure-driven flow. This and associated flow configurations are explored in this paper. LB results are in excellent agreement with existing theory and numerical results for simple pressure-driven flow between parallel plates, for flow through a periodic medium of spheres [Zick AA, Homsy GM. Stokes flow through periodic arrays of spheres. Journal of Fluid Mechanics 1982; 115:13], and for the force and torque acting on a sphere held fixed at the quarter vertical position in a pressure-driven flow between parallel plates. In the latter case, LB calculations reveal a screening effect caused by neighboring periodic images of the test sphere. It is shown that the test sphere is hydrodynamically decoupled from its periodic images when separated by approximately 30 sphere radii. LB results for force and torque as a function of sphere height and flow cell height are also reported. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Univ Calif Lawrence Livermore Natl Lab, EETD, Ctr Computat Engn, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, EETD, Ctr Microtechnol, Livermore, CA USA. RP Clague, DS (reprint author), Univ Calif Lawrence Livermore Natl Lab, EETD, Ctr Computat Engn, L-223, Livermore, CA 94550 USA. NR 17 TC 9 Z9 9 U1 0 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0271-2091 J9 INT J NUMER METH FL JI Int. J. Numer. Methods Fluids PD JAN 15 PY 2001 VL 35 IS 1 BP 55 EP 70 DI 10.1002/1097-0363(20010115)35:1<55::AID-FLD83>3.0.CO;2-W PG 16 WC Computer Science, Interdisciplinary Applications; Mathematics, Interdisciplinary Applications; Mechanics; Physics, Fluids & Plasmas SC Computer Science; Mathematics; Mechanics; Physics GA 395XB UT WOS:000166605600004 ER PT J AU Foteinopoulou, S Rosenberg, A Sigalas, MM Soukoulis, CM AF Foteinopoulou, S Rosenberg, A Sigalas, MM Soukoulis, CM TI In- and out-of-plane propagation of electromagnetic waves in low index contrast two dimensional photonic crystals SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PERIODIC DIELECTRIC STRUCTURES; BAND-GAP; TRANSMITTANCE; GUIDANCE; LATTICES; AIR AB Propagation of electromagnetic waves through a two-dimensional triangular lattice has been studied for different values of refractive index contrast between the constituent dielectrics, and for angles of incidence both in and out of the plane of periodicity. Transmission results have been obtained both experimentally and with the transfer matrix technique, and good agreement has been found between the two. Comparison with band structure calculations has also been made. (C) 2001 American Institute of Physics. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. USN, Res Lab, Washington, DC 20375 USA. RP Foteinopoulou, S (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. RI Soukoulis, Costas/A-5295-2008 NR 25 TC 35 Z9 35 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 15 PY 2001 VL 89 IS 2 BP 824 EP 830 DI 10.1063/1.1330250 PG 7 WC Physics, Applied SC Physics GA 387WG UT WOS:000166144400002 ER PT J AU Hebner, GA AF Hebner, GA TI CF, CF2, and SiF densities in inductively driven discharges containing C2F6, C4F8, and CHF3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LASER-INDUCED FLUORESCENCE; ABSORPTION-SPECTROSCOPY; RADICAL DENSITIES; DIFFUSION-COEFFICIENT; SPATIAL UNIFORMITY; ETCHING PLASMAS; REFERENCE CELL; ION; GAS; POLYMERIZATION AB Laser induced fluorescence was used to measure the spatially resolved CF, CF2, and SiF radical density in inductively driven discharges containing fluorocarbon gases. Measurements of the spatially resolved CF density were performed in C2F6, and CHF3 containing discharges as functions of inductive power, pressure and bias condition on a silicon substrate. In addition, CF rotational temperatures were calculated, assuming saturated spectra. Measurements of the spatially resolved CF2 and SiF density were performed in C4F8, C2F6, and CHF3 containing discharges as functions of inductive power, pressure and bias condition. SiF rotational temperatures were also estimated. As the induction coil power was increased, the SiF density in the center (r=0 cm) increased while the CF2 density decreased and the CF density slightly decreased. In all cases, the radical density in the center of the glow increased with pressure changes from 5 to 30 mTorr while changes in the bias power had little influence on any of the measured radical densities. The spatial distribution of the CF and SiF density peaked in the center of the discharge. The CF2 density had a local maximum in the center of the plasma with a decreasing density at the edge of the glow. However, the CF2 density outside the glow region was a factor of 2-6 higher than the density inside the glow region, depending on the gas. CF and SiF rotational temperatures were between 450 and 750 K. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 34 TC 36 Z9 36 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 15 PY 2001 VL 89 IS 2 BP 900 EP 910 DI 10.1063/1.1332092 PG 11 WC Physics, Applied SC Physics GA 387WG UT WOS:000166144400013 ER PT J AU Ballif, C Moutinho, HR Al-Jassim, MM AF Ballif, C Moutinho, HR Al-Jassim, MM TI Cross-sectional electrostatic force microscopy of thin-film solar cells SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SCANNING CAPACITANCE MICROSCOPY; SEMICONDUCTOR SURFACES; TUNNELING-MICROSCOPY; PROBE MICROSCOPY; DEVICES; POTENTIOMETRY; TIP AB In a recent work, we showed that atomic force microscopy (AFM) is a powerful technique to image cross sections of polycrystalline thin films. In this work, we apply a modification of AFM, namely, electrostatic force microscopy (EFM), to investigate the electronic properties of cleaved II-VI and multijunction thin-film solar cells. We cleave the devices in such a way that they are still working with their nominal photovoltaic efficiencies and can be polarized for the measurements. This allows us to differentiate between surface effects (work function and surface band bending) and bulk device properties. In the case of polycrystalline CdTe/CdS/SnO2/glass solar cells, we find a drop of the EFM signal in the area of the CdTe/CdS interface (+/- 50 nm). This drop varies in amplitude and sign according to the applied external bias and is compatible with an n-CdS/p-CdTe heterojunction model, thereby invalidating the possibility of a deeply buried n-p CdTe homojunction. In the case of a triple-junction GaInP/GaAs/Ge device, we observe a variation of the EFM signal linked to both the material work-function differences and to the voltage bias applied to the cell. We attempt a qualitative explanation of the results and discuss the implications and difficulties of the EFM technique for the study of such thin-film devices. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Moutinho, HR (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Ballif, Christophe/G-4621-2012 NR 46 TC 30 Z9 30 U1 3 U2 24 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 15 PY 2001 VL 89 IS 2 BP 1418 EP 1424 DI 10.1063/1.1329669 PG 7 WC Physics, Applied SC Physics GA 387WG UT WOS:000166144400084 ER PT J AU Chau, R Mitchell, AC Minich, RW Nellis, WJ AF Chau, R Mitchell, AC Minich, RW Nellis, WJ TI Electrical conductivity of water compressed dynamically to pressures of 70-180 GPa (0.7-1.8 Mbar) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID 1.4 MBAR; TEMPERATURE; HYDROGEN; AMMONIA AB The electrical conductivity of water was measured at high pressures (70 to 180 GPa) and temperatures (4000 to 11 000 K) using a reverberating shock wave technique. The measured electrical conductivity of water varies from 39 to 200 Omega (-1) cm(-1) between 70 and 180 GPa. The relatively weak pressure dependence of the electrical conductivity is consistent with water being fully ionized chemically and the primary conduction mechanism is highly mobile protons. The results are in contrast to hydrogen, in which electrons are the dominant charge carriers. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Chau, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 24 TC 49 Z9 49 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2001 VL 114 IS 3 BP 1361 EP 1365 DI 10.1063/1.1332079 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 388ZN UT WOS:000166213100035 ER PT J AU Oprea, M Cowell, LG Kepler, TB AF Oprea, M Cowell, LG Kepler, TB TI The targeting of somatic hypermutation closely resembles that of meiotic mutation SO JOURNAL OF IMMUNOLOGY LA English DT Article ID IMMUNOGLOBULIN VARIABLE GENES; MISMATCH REPAIR PROTEIN; B-CELLS; NUCLEOTIDE SUBSTITUTIONS; AFFINITY MATURATION; MICE DEFICIENT; DNA STRANDS; SEQUENCES; V(D)J; DINUCLEOTIDE AB We have compared the microsequence specificity of mutations introduced during somatic hypermutation (SH) and those introduced meiotically during neutral evolution. We have minimized the effects of selection by studying nonproductive thence unselected) Ig V region genes for somatic mutations and processed pseudogenes for meiotic mutations. We find that the two sets of patterns are very similar: the mutabilities of nucleotide triplets are positively correlated between the somatic and meiotic sets. The major differences that do exist fall into three distinct categories: 1) The mutability is sharply higher at CG dinucleotides under meiotic but not somatic mutation. 2) The complementary triplets AGC and GCT are much more mutable under somatic than under meiotic mutation. 3) Triplets of the form WAN (W = T or A) are uniformly more mutable under somatic than under meiotic mutation. Nevertheless, the relative mutabilities both within this set and within the SAN (S = G or C) triplets are highly correlated with those under meiotic mutation. We also find that the somatic triplet specificity is strongly symmetric under strand exchange for A/T triplets as well as for G/C triplets in spite of the strong predominance of A over T mutations, Thus, we suggest that somatic mutation has at least two distinct components: one that specifically targets AGC/GCT triplets and another that acts as true catalysis of meiotic mutation. C1 Santa Fe Inst, Santa Fe, NM 87501 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Duke Univ, Med Ctr, Dept Immunol, Durham, NC 27710 USA. RP Kepler, TB (reprint author), Santa Fe Inst, 1399 Hyde Pk Rd, Santa Fe, NM 87501 USA. OI Kepler, Thomas/0000-0002-1383-6865 FU NIAID NIH HHS [AI28433] NR 46 TC 25 Z9 25 U1 0 U2 1 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD JAN 15 PY 2001 VL 166 IS 2 BP 892 EP 899 PG 8 WC Immunology SC Immunology GA 389VP UT WOS:000166259600025 PM 11145665 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Logan, J Gerasimov, M Maynard, L Ding, YS Gatley, SJ Gifford, A Franceschi, D AF Volkow, ND Wang, GJ Fowler, JS Logan, J Gerasimov, M Maynard, L Ding, YS Gatley, SJ Gifford, A Franceschi, D TI Therapeutic doses of oral methylphenidate significantly increase extracellular dopamine in the human brain SO JOURNAL OF NEUROSCIENCE LA English DT Article DE attention deficit hyperactivity disorder; raclopride; Ritalin; D2 receptors; striatum; positron emission tomography; imaging; dopamine transporters ID DEFICIT-HYPERACTIVITY DISORDER; C-11 RACLOPRIDE; INTRAVENOUS METHYLPHENIDATE; SYNAPTIC DOPAMINE; EMISSION TOMOGRAPHY; AMPHETAMINE; TRANSPORTER; COCAINE; BINDING; ABUSE AB Methylphenidate (Ritalin) is the most commonly prescribed psychoactive drug in children for the treatment of attention deficit hyperactivity disorder (ADHD), yet the mechanisms responsible for its therapeutic effects are poorly understood. Whereas methylphenidate blocks the dopamine transporter (main mechanism for removal of extracellular dopamine), it is unclear whether at doses used therapeutically it significantly changes extracellular dopamine (DA) concentration. Here we used positron emission tomography and [C-11] raclopride (D2 receptor radioligand that competes with endogenous DA for binding to the receptor) to evaluate whether oral methylphenidate changes extracellular DA in the human brain in 11 healthy controls. We showed that oral methylphenidate (average dose 0.8 +/- 0.11 mg/kg) significantly increased extracellular DA in brain, as evidenced by a significant reduction in B-max/K-d (measure of D2 receptor availability) in striatum (20 +/- 12%; p < 0.0005). These results provide direct evidence that oral methylphenidate at doses within the therapeutic range significantly increases extracellular DA in human brain. This result coupled with recent findings of increased dopamine transporters in ADHD patients (which is expected to result in reductions in extracellular DA) provides a mechanistic framework for the therapeutic efficacy of methylphenidate. The increase in DA caused by the blockade of dopamine transporters by methylphenidate predominantly reflects an amplification of spontaneously released DA, which in turn is responsive to environmental stimulation. Because DA decreases background firing rates and increases signal-to-noise in target neurons, we postulate that the amplification of weak DA signals in subjects with ADHD by methylphenidate would enhance task-specific signaling, improving attention and decreasing distractibility. Alternatively methylphenidate-induced increases in DA, a neurotransmitter involved with motivation and reward, could enhance the salience of the task facilitating the "interest that it elicits" and thus improving performance. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NR 40 TC 29 Z9 29 U1 6 U2 22 PU SOC NEUROSCIENCE PI WASHINGTON PA 11 DUPONT CIRCLE, NW, STE 500, WASHINGTON, DC 20036 USA SN 0270-6474 J9 J NEUROSCI JI J. Neurosci. PD JAN 15 PY 2001 VL 21 IS 2 BP U1 EP U5 PG 5 WC Neurosciences SC Neurosciences & Neurology GA 394WB UT WOS:000166545300001 ER PT J AU Guilderson, TP Fairbanks, RG Rubenstone, JL AF Guilderson, TP Fairbanks, RG Rubenstone, JL TI Tropical Atlantic coral oxygen isotopes: glacial-interglacial sea surface temperatures and climate change SO MARINE GEOLOGY LA English DT Article DE last glacial maximum; oxygen isotopes; climate; paleo-oceanography ID YOUNGER DRYAS EVENT; LAST DEGLACIATION; NORTH-ATLANTIC; POLLEN RECORD; WEST-INDIES; OCEAN; MAXIMUM; WATER; BARBADOS; MASS AB We have generated a detailed oxygen isotope time-series from the fossil coral reefs from offshore Barbados. The Barbados coral-based record is a unique paleoceanographic data set with an equivalent sedimentation rate in excess of 600 cm/kyr where not only is the annual signal uniquely preserved but seasonality as well. Oxygen isotope values during the late glacial and LGM (16-20 (14)C kyrs; 19-24 calendar kyrs) are similar to2.3 parts per thousand heavier than corresponding living specimens, and indicate a regional cooling on the order of 4.5 degreesC. There is also an isotopic expression of the Bolling-Pre-Boreal climate oscillation, with values reflecting a cooling during the Younger Dryas. Seasonality, a key diagnostic of the state of the climate system, remained the same or slightly less than present and indicates that the observed coolings were a change in the mean state of the western tropical Atlantic. Pan-tropic cooling during the last glaciation is best explained by a change in the radiative balance of the tropics. Variable tropical sea surface temperatures during climate oscillations such as the Younger Dryas challenge the paradigm that climate change only cascades from variations in North Atlantic deep water production. (C) 2001 Elsevier Science Ltd All rights reserved. C1 Lamont Doherty Earth Observ, Palisades, NY USA. Columbia Univ, Dept Earth & Environm Sci, New York, NY 10027 USA. RP Guilderson, TP (reprint author), Lawrence Livermore Natl Lab, Ctr AMS, 7000 East Ave L-397, Livermore, CA 94551 USA. EM guilderson1@popeye.llnl.gov NR 62 TC 46 Z9 50 U1 2 U2 21 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0025-3227 J9 MAR GEOL JI Mar. Geol. PD JAN 15 PY 2001 VL 172 IS 1-2 BP 75 EP 89 DI 10.1016/S0025-3227(00)00115-8 PG 15 WC Geosciences, Multidisciplinary; Oceanography SC Geology; Oceanography GA 400TR UT WOS:000166888200005 ER PT J AU Smith, ES AF Smith, ES TI Recent results from Jefferson Lab SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT International Conference on Quark Nuclear Physics (QNP 2000) CY FEB 21-25, 2000 CL ADELAIDE, AUSTRALIA SP Univ Adelaide, Special Res Ctr Subatom Struct Matter, Jefferson Lab, CSSM, Natl Inst Theoret Phys ID STRUCTURE-FUNCTION A(Q(2)); HEARN SUM-RULE; PROTON AB Precision measurements of the structure of nucleons and nuclei in the regime of strong interaction QCD are now possible with the availability of high current polarized electron beams, polarized targets, and recoil polarimeters, in conjunction with modern spectrometers and detector instrumentation. We present some recent results from the Jefferson Lab on the charge and current distributions of nucleons and nuclei. We also review measurements which relate physics at small distances to the regime where strong interaction QCD is the relevant theory. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Smith, ES (reprint author), Jefferson Lab, Newport News, VA 23606 USA. NR 35 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 15 PY 2001 VL 680 IS 1-4 BP 1C EP 9C PG 9 WC Physics, Nuclear SC Physics GA 392XE UT WOS:000166437200002 ER PT J AU Melnitchouk, W AF Melnitchouk, W TI Local quark-hadron duality in structure functions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT International Conference on Quark Nuclear Physics (QNP 2000) CY FEB 21-25, 2000 CL ADELAIDE, AUSTRALIA SP Univ Adelaide, Special Res Ctr Subatom Struct Matter, Jefferson Lab, CSSM, Natl Inst Theoret Phys AB We examine the consequences of local duality for elastic scattering, and derive model-independent relations between structure functions at x similar to 1 and elastic electromagnetic form factors. C1 Univ Adelaide, Special Res Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia. Jefferson Lab, Newport News, VA 23606 USA. RP Melnitchouk, W (reprint author), Univ Adelaide, Special Res Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia. NR 10 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 15 PY 2001 VL 680 IS 1-4 BP 52C EP 57C PG 6 WC Physics, Nuclear SC Physics GA 392XE UT WOS:000166437200009 ER PT J AU Adams, GS Adams, T Bar-Yam, Z Bishop, JM Bodyagin, VA Brabson, BB Brown, DS Cason, NM Chung, SU Crittenden, RR Cummings, JP Danyo, K Denisov, S Dorofeev, V Dowd, JP Dzierba, AR Eugenio, P Gunter, J Hackenburg, RW Hayek, M Ivanov, EI Kachaev, I Kern, W King, E Kodolova, OL Korotkikh, VL Kostin, MA Kuhn, J Lindenbusch, R Lipaev, V LoSecco, JM Manak, JJ Napolitano, J Nozar, M Olchanski, C Ostrovidov, AI Pedlar, TK Popov, A Rust, DR Ryabchikov, D Sanjari, AH Sarycheva, LI Scott, E Seth, KK Shenhav, N Shephard, WD Sinev, NB Smith, JA Smith, PT Stienike, DL Sulanke, T Taegar, SA Teige, S Thompson, DR Vardanyan, IN Weygand, DP White, D Willutzki, HJ Wise, J Witkowski, M Yershov, AA Zhao, D AF Adams, GS Adams, T Bar-Yam, Z Bishop, JM Bodyagin, VA Brabson, BB Brown, DS Cason, NM Chung, SU Crittenden, RR Cummings, JP Danyo, K Denisov, S Dorofeev, V Dowd, JP Dzierba, AR Eugenio, P Gunter, J Hackenburg, RW Hayek, M Ivanov, EI Kachaev, I Kern, W King, E Kodolova, OL Korotkikh, VL Kostin, MA Kuhn, J Lindenbusch, R Lipaev, V LoSecco, JM Manak, JJ Napolitano, J Nozar, M Olchanski, C Ostrovidov, AI Pedlar, TK Popov, A Rust, DR Ryabchikov, D Sanjari, AH Sarycheva, LI Scott, E Seth, KK Shenhav, N Shephard, WD Sinev, NB Smith, JA Smith, PT Stienike, DL Sulanke, T Taegar, SA Teige, S Thompson, DR Vardanyan, IN Weygand, DP White, D Willutzki, HJ Wise, J Witkowski, M Yershov, AA Zhao, D TI Experimental evidence for hadroproduction of exotic mesons SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT International Conference on Quark Nuclear Physics (QNP 2000) CY FEB 21-25, 2000 CL ADELAIDE, AUSTRALIA SP Univ Adelaide, Special Res Ctr Subatom Struct Matter, Jefferson Lab, CSSM, Natl Inst Theoret Phys ID FLUX-TUBE MODEL; 18 GEV/C; QCD; HYBRID AB New measurements of peripheral meson production are presented. The data confirm the existence of exotic mesons at 1.4 and 1.6 GeV/c(2). The latter state dominates the eta'pi (-) decay spectrum. The data on eta pi (+)pi (-)pi (-) decay show large strength in several exotic (J(pc)=1(-+)) waves as well. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow 119899, Russia. Univ Massachusetts, Dept Phys, N Dartmouth, MA 02747 USA. Rensselaer Polytech Inst, Dept Phys, Troy, NY 12180 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Inst High Energy Phys, Protvino 142284, Russia. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Brookhaven Natl Lab, Upton, NY 11973 USA. EM adamsg@rpi.edu RI Vardanyan, Irina/K-7981-2012; Weygand, Daniel/D-7203-2013 NR 14 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 15 PY 2001 VL 680 IS 1-4 BP 335C EP 341C PG 7 WC Physics, Nuclear SC Physics GA 392XE UT WOS:000166437200061 ER PT J AU Brodsky, SJ Hwang, DS Ma, BQ Schmidt, I AF Brodsky, SJ Hwang, DS Ma, BQ Schmidt, I TI Light-cone representation of the spin and orbital angular momentum of relativistic composite systems SO NUCLEAR PHYSICS B LA English DT Article ID TWIST PARTON DISTRIBUTIONS; CONSTITUENT QUARK-MODEL; QUANTUM CHROMODYNAMICS; EXCLUSIVE PROCESSES; FORM-FACTORS; EVOLUTION-EQUATIONS; MAGNETIC-MOMENTS; NUCLEON SPIN; SUM-RULES; ART. AB The matrix elements of local operators such as the electromagnetic current, the energy-momentum tensor, angular momentum, and the moments of structure functions have exact representations in terms of light-cone Fock state wavefunctions of bound states such as hadrons. We illustrate all of these properties by giving explicit light-cone wavefunctions for the two-particle Fock state of the electron in QED, thus connecting the Schwinger anomalous magnetic moment to the spin and orbital angular momentum carried by its Fock state constituents. We also compute the QED one-loop radiative corrections for the form factors for the graviton coupling to the electron and photon. Although the underlying model is derived from elementary QED perturbative couplings, it in fact can be used to simulate much more general bound state systems by applying spectral integration over the constituent masses while preserving all of the Lorentz properties, giving explicit realization of the spin sum rules and other local matrix elements. The role of orbital angular momentum in understanding the "spin crisis" problem for relativistic systems is clarified. We also prove that the anomalous gravitomagnetic moment B(0) vanishes for any composite system. This property is shown to follow directly from the Lorentz boost properties of the light-cone Fock representation and holds separately for each Fock state component. We show how the QED perturbative structure can be used to model bound state systems while preserving all Lorentz properties. We thus obtain a theoretical laboratory to test the consistency of formulae which have been proposed to probe the spin structure of hadrons. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Sejong Univ, Dept Phys, Seoul 143747, South Korea. CCAST, World Lab, Beijing 100080, Peoples R China. Peking Univ, Dept Phys, Beijing 100871, Peoples R China. Acad Sinica, Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Tecn Federico Santa Maria, Dept Fis, Valparaiso, Chile. RP Brodsky, SJ (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM sjbth@slac.stanford.edu; dshwang@kunja.sejong.ac.kr; mabq@th.phy.pku.edu.cn; ischmidt@fis.utfsm.cl RI Schmidt, Ivan/J-5920-2012 NR 48 TC 204 Z9 204 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD JAN 15 PY 2001 VL 593 IS 1-2 BP 311 EP 335 DI 10.1016/S0550-3213(00)00626-X PG 25 WC Physics, Particles & Fields SC Physics GA 392LK UT WOS:000166412400012 ER PT J AU Shore, BW Johnson, MA Kulander, KC Davis, JI AF Shore, BW Johnson, MA Kulander, KC Davis, JI TI The livermore experience: Contributions of J. H. Eberly to laser excitation theory SO OPTICS EXPRESS LA English DT Article; Proceedings Paper CT Symposium on Quantum Control of Photons and Matter held in honor of Joseph H Eberly CY OCT 20-21, 2000 CL ROCHESTER, NEW YORK ID ABOVE-THRESHOLD IONIZATION; WAVELENGTH OPTICAL PULSES; N-LEVEL ATOMS; MULTIPHOTON IONIZATION; POPULATION TRANSFER; ISOTOPE-SEPARATION; RESONANCE FLUORESCENCE; COHERENT DYNAMICS; 3-LEVEL SYSTEM; INTENSE PULSES AB This article summarizes the developing understanding of coherent atomic excitation, as gained through a collaboration of J. H. Eberly with the Laser Isotope Separation Program of the Lawrence Livermore National Laboratory, particularly aspects of coherence, population trapping, multilevel multiphoton excitation sequences, analytic solutions to multistate excitation chains, the quasicontinuum, pulse propagation, and noise. In addition to the discovery of several curious and unexpected properties of coherent excitation, mentioned here, the collaboration provided an excellent example of unexpected benefits from investment into basic research. (C) 2001 Optical Society of America. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Shore, BW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 64 TC 5 Z9 5 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD JAN 15 PY 2001 VL 8 IS 2 BP 28 EP 43 PG 16 WC Optics SC Optics GA 391HC UT WOS:000166349700002 PM 19417783 ER PT J AU Milonni, PW Furuya, K Chiao, RY AF Milonni, PW Furuya, K Chiao, RY TI Quantum theory of superluminal pulse propagation SO OPTICS EXPRESS LA English DT Article; Proceedings Paper CT Symposium on Quantum Control of Photons and Matter held in honor of Joseph H Eberly CY OCT 20-21, 2000 CL ROCHESTER, NEW YORK AB We consider the propagation in a dielectric medium of radiation emitted by a single-atom source. The source and dielectric atoms are assumed to be two-state systems, and the emitted light is incident on an ideal broadband detector. It is shown that the peak probability for producing a "click" at the detector can occur sooner than it could if there were no material medium between it and the source atom. (C) 2001 Optical Society of America. C1 Univ Calif Los Alamos Natl Lab, Theoret Div T4, Los Alamos, NM 87545 USA. Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Milonni, PW (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div T4, Los Alamos, NM 87545 USA. RI Inst. of Physics, Gleb Wataghin/A-9780-2017 NR 7 TC 7 Z9 8 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD JAN 15 PY 2001 VL 8 IS 2 BP 59 EP 65 PG 7 WC Optics SC Optics GA 391HC UT WOS:000166349700005 PM 19417786 ER PT J AU Mackie, M Timmermans, E Cote, R Javanainen, J AF Mackie, M Timmermans, E Cote, R Javanainen, J TI Driving superfluidity with photoassociation SO OPTICS EXPRESS LA English DT Article; Proceedings Paper CT Symposium on Quantum Control of Photons and Matter held in honor of Joseph H Eberly CY OCT 20-21, 2000 CL ROCHESTER, NEW YORK ID BOSE-EINSTEIN CONDENSATION; SCATTERING LENGTH; RESONANT LIGHT; ATOMS; COLLISIONS; STATE; LITHIUM; TRAP; LI-6; GAS AB We theoretically examine photoassociation of a two-component Fermi degenerate gas. Our focus is on adjusting the atom-atom interaction, and thereby increasing the critical temperature of the BCS transition to the superfluid state. In order to avoid spontaneous decay of the molecules, the photoassociating light must be far-off resonance. Very high light intensities are therefore required for effective control of the BCS transition. (C) 2001 Optical Society of America. C1 Univ Helsinki, Helsinki Inst Phys, FIN-00014 Helsingin Yliopisto, Finland. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. RP Mackie, M (reprint author), Univ Helsinki, Helsinki Inst Phys, PL 9, FIN-00014 Helsingin Yliopisto, Finland. RI Javanainen, Juha/B-7350-2008 NR 26 TC 10 Z9 10 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD JAN 15 PY 2001 VL 8 IS 2 BP 118 EP 122 PG 5 WC Optics SC Optics GA 391HC UT WOS:000166349700013 PM 19417794 ER PT J AU Nieto, MM Truax, DR AF Nieto, MM Truax, DR TI Symmetries and solutions of the three-dimensional Paul trap SO OPTICS EXPRESS LA English DT Article; Proceedings Paper CT Symposium on Quantum Control of Photons and Matter held in honor of Joseph H Eberly CY OCT 20-21, 2000 CL ROCHESTER, NEW YORK ID SUPERSYMMETRY AB Using the symmetries of the three-dimensional Paul trap, we derive the solutions of the time-dependent Schrodinger equation for this system, in both Cartesian and cylindrical coordinates. Our symmetry calculations provide insights that are not always obvious from the conventional viewpoint. (C) 2001 Optical Society of America. C1 Univ Calif Los Alamos Natl Lab, Theoret Div MS B285, Los Alamos, NM 87545 USA. Univ Calgary, Dept Chem, Calgary, AB T2N 1N4, Canada. RP Nieto, MM (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div MS B285, Los Alamos, NM 87545 USA. NR 17 TC 1 Z9 1 U1 2 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD JAN 15 PY 2001 VL 8 IS 2 BP 123 EP 130 PG 8 WC Optics SC Optics GA 391HC UT WOS:000166349700014 PM 19417795 ER PT J AU Farrar, CR Doebling, SW Nix, DA AF Farrar, CR Doebling, SW Nix, DA TI Vibration-based structural damage identification SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE damage detection; structural health monitoring; statistical pattern recognition AB Many aerospace, civil and mechanical systems continue to be used despite ageing and the associated potential for damage accumulation. Therefore, the ability to monitor the structural health of these systems is becoming increasingly important. A wide variety of highly effective local non-destructive evaluation tools is available. However, damage identification based upon changes in vibration characteristics is one of the few methods that monitor changes in the structure on a global basis. A summary of developments in the field of global structural health monitoring that have taken place over the last thirty years is first presented. Vibration-based damage detection is a primary tool that is employed for this monitoring. Next, the process of vibration-based damage detection will be described as a problem in statistical pattern recognition. This process is composed of three portions: (i) data acquisition and cleansing; (ii) feature selection and data compression; and (iii) statistical model development. Current research regarding feature selection and statistical model development will be emphasized with the application of this technology to a large-scale laboratory structure. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Farrar, CR (reprint author), Univ Calif Los Alamos Natl Lab, MS P-946, Los Alamos, NM 87545 USA. RI Farrar, Charles/C-6954-2012 NR 15 TC 338 Z9 346 U1 4 U2 45 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T ROY SOC A JI Philos. Trans. R. Soc. Lond. Ser. A-Math. Phys. Eng. Sci. PD JAN 15 PY 2001 VL 359 IS 1778 BP 131 EP 149 PG 19 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 396ND UT WOS:000166642200009 ER PT J AU Patnaik, S Budhani, RC Konczykowski, M Wang, YL Suenaga, M AF Patnaik, S Budhani, RC Konczykowski, M Wang, YL Suenaga, M TI Radio frequency vortex dynamics in heavy ion irradiated (Bi-Pb)(2)ST2Ca2Cu3O10 superconducting platelets SO PHYSICA C LA English DT Article DE irradiation effects; vortex dynamics; flux pinning ID CU-O CRYSTALS; COLUMNAR DEFECTS; II SUPERCONDUCTORS; BOSON LOCALIZATION; LINEAR DEFECTS; MAGNETIC-FIELD; FLUX-CREEP; PB IONS; TAPES; BI2SR2CACU2O8+DELTA AB We report measurements of vortex dynamics in heavy ion irradiated (Bi-Pb)(2)Sr2Ca2Cu3O10 superconducting tapes in the high-temperature (T greater than or equal to 60 K) and low-field (mu H-0 < 0.3 T) regimes. The temperature, magnetic field strength and angular dependences of radio-frequency (RF) penetration depth lambda (H, T) are measured and compared with the behavior of unirradiated samples. The pinning force constant, k(p), and viscosity coefficient eta are extracted from the field dependence of lambda (H, T), The angular dependence of the RF penetration depth in samples irradiated at the field equivalent fluence of 0.5 and 3.0 T is minimum when the external field is brought into alignment with the columnar defects (CDs), While this characteristic feature of anisotropic pinning due to CDs disappear in a temperature regime where J(c) is high, in the vortex liquid state closer to T-c, this feature grows with the increasing field strength. The overall changes in eta, k(p) and the angular dependence of lambda (H, T) are discussed in the framework of the Bose glass theory for vortex dynamics in highly layered superconductors, (C) 2001 Published by Elsevier Science Ltd. All rights reserved. C1 Indian Inst Technol, Dept Phys, Kanpur 208016, Uttar Pradesh, India. Ecole Polytech, Solides Irradies Lab, F-91128 Palaiseau, France. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Budhani, RC (reprint author), Univ Wisconsin, Ctr Appl Superconduct, Madison, WI 53706 USA. NR 39 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JAN 15 PY 2001 VL 349 IS 3-4 BP 155 EP 165 DI 10.1016/S0921-4534(00)01516-1 PG 11 WC Physics, Applied SC Physics GA 396VA UT WOS:000166656100001 ER PT J AU Serquis, A Morales, L Caneiro, A Basset, A Short, S Hodges, JP Jorgensen, JD AF Serquis, A Morales, L Caneiro, A Basset, A Short, S Hodges, JP Jorgensen, JD TI Synthesis methods and characterization of (Hg,Re)-1201 SO PHYSICA C LA English DT Article DE Hg-base superconductors; effects of material synthesis; cationic defects; oxygen stoichiometry ID SUPERCONDUCTING PROPERTIES; HGBA2CUO4+DELTA PHASE; CRYSTAL-STRUCTURE; SINGLE-CRYSTALS; HIGH-PRESSURE; T-C; HG; MERCURY; HGBA2CA2CU3O8+DELTA; DIFFRACTION AB We analyze the influence of the preparation method and Re content on the chemical stability, thermodynamic properties and superconducting response of Hg1-chiRechiBa2CuO4+delta (0 < chi < 0.2) samples. The route of synthesis is also investigated to optimize the incorporation of Re in the Hg-1201 structure. The samples are characterized by X-ray diffraction, scanning electron microscopy and microanalysis. and the influence of Re content on the oxygen stoichiometry is studied by means of thermogravimetry. The superconducting response of samples and their aging are studied by d.c. susceptibility. We find that Re doping increases the thermodynamic stability due to the incorporation of highly bonded oxygen atoms in the (Hg,Re)--O-delta planes, In addition, Re-free samples prepared with Hg excess remain stable for long periods under ambient atmosphere. An optimal synthesis method and the Hg excess would avoid the formation of amorphous phases composed of Ba and Cu oxides which are responsible of such degradation in samples with Hg deficiency. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. Ctr Atom Bariloche, Inst Balseiro, RA-8400 Bariloche, Rio Negro, Argentina. Univ Nacl Comahue, Neuquen, Argentina. Argonne Natl Lab, Argonne, IL 60439 USA. RP Caneiro, A (reprint author), Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. RI Hodges, Jason/K-1421-2013; Serquis, Adriana/L-6554-2015; OI Serquis, Adriana/0000-0003-1499-4782; Hodges, Jason/0000-0003-3016-4578 NR 37 TC 2 Z9 2 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JAN 15 PY 2001 VL 349 IS 3-4 BP 305 EP 316 DI 10.1016/S0921-4534(00)01545-8 PG 12 WC Physics, Applied SC Physics GA 396VA UT WOS:000166656100018 ER PT J AU Consorte, CD Fong, CY Watson, MD Yang, LH Ciraci, S AF Consorte, CD Fong, CY Watson, MD Yang, LH Ciraci, S TI Reaction path for Te during surfactant-mediated epitaxial growth of GaAs (100) SO PHYSICAL REVIEW B LA English DT Article ID GAAS(001); MECHANISM AB Using first-principles calculations and experimental evidence concerning the essential environment for surfactant-mediated epitaxial growth on the GaAs/Te(100) surface, we determine a short-ranged reaction path for the As <----> Te exchange that is energetically favorable and prepares the surface for continued layer-by-layer growth. Furthermore, we explain the required partial coverage of the surfactant atoms as well as the required presence of both As and Ga adatoms. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Bilkent Univ, Dept Phys, TR-06533 Bilkent, Turkey. RP Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. NR 20 TC 5 Z9 5 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2001 VL 63 IS 4 AR 041301 DI 10.1103/PhysRevB.63.041301 PG 4 WC Physics, Condensed Matter SC Physics GA 398HJ UT WOS:000166750600005 ER PT J AU Jung, MH Ekino, T Kwon, YS Takabatake, T AF Jung, MH Ekino, T Kwon, YS Takabatake, T TI Tunneling spectroscopy of RTe2 (R = La, Ce) and possible coexistence between charge-density waves and magnetic order SO PHYSICAL REVIEW B LA English DT Article ID GAP; CETE2 AB Tunneling spectra are measured on the charge-density wave (CDW) compound LaTe2 and the isostructural antiferromagnet CeTe2 with T-N=4.3 K by a break-junction method. In contrast to the well-developed CDW gap 2 Delta = 0.9 eV wide for LaTe2, the spectrum of polycrystal CeTe2 is V shaped with 2 Delta = 1.2 eV. These gap structures agree with the optical-conductivity spectra for both compounds. The V-shaped spectrum for CeTe2 suggests that the CDW gap is modified by the presence of electronic states hybridized with the 4f electron states. A smaller gap 2 Delta* = 0.5 eV was observed for the bulk tunneling current in the c plane of single crystals of CeTe2. On cooling below T-C=6.1 K, where a short-range ferromagnetic order sets in, 2 Delta* exhibits a sharp minimum. Furthermore, subgap anomalies appear below T-C and suddenly increase at T-N The normalized zero-bias conductance shows a minimum at T-C and a sudden increase below T-N. These facts suggest possible interplay of CDW's and magnetic order in CeTe2. C1 Hiroshima Univ, ADSM, Dept Quantum Matter, Higashihiroshima 7398526, Japan. Hiroshima Univ, Fac Integrated Arts & Sci, Higashihiroshima 7398521, Japan. Sungkyunkwan Univ, Dept Phys, Suwon 440746, South Korea. RP Jung, MH (reprint author), Los Alamos Natl Lab, NHMFL, Pulse Field Facil, Los Alamos, NM 87545 USA. RI Takabatake, Toshiro/L-2882-2014 OI Takabatake, Toshiro/0000-0002-3293-8592 NR 28 TC 10 Z9 10 U1 0 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 JAN 15 PY 2001 VL 63 IS 3 AR 035101 PG 5 WC Physics, Condensed Matter SC Physics GA 395YJ UT WOS:000166608600033 ER PT J AU Lange, RJ Lee, SJ Kim, KJ Canfield, PC Lynch, DW AF Lange, RJ Lee, SJ Kim, KJ Canfield, PC Lynch, DW TI Optical and magneto-optical properties and electronic structures of single-crystalline RAI(2) (R = Y, La, Ce, Pr, and Lu) SO PHYSICAL REVIEW B LA English DT Article ID KERR ROTATION; CEAL2; LAAL2; LUAL2; YAL2 AB The diagonal optical conductivity spectra of single crystals of RAl2 (R=Y, La, Ce, Pr, and Lu) were measured at room temperature by spectroscopic ellipsometry in the 1.5-5.6-eV range. Ail the compounds exhibit two strong interband absorption peaks at about 1.8 and 3.6 eV for YAl2 and LuAl2, and at about 2.0 and 3.0 eV for LaAl2, CeAl2, and PrAl2. Such differences in the second peak position appear in the theoretical optical conductivity spectra calculated from their band structures obtained by the tight-binding linear-muffin-tin-orbitals method. Most of the contributions to the two peaks in LaAl2 are from the p and d states, i.e., p -->d and d-->p transitions, while those involving f states are negligible. These results suggest that f character near E-F for LaAl2, CeAl2, and PrAl2 distorts their conduction bands significantly through hybridization, leading to different optical spectra compared to those of YAl2 and LuAl2. The magneto-optical properties of CeAl2 and PrAl2 were measured at low temperatures. The Kerr rotation (Theta (K)) and ellipticity (epsilon (K)) for both compounds show similar spectral variations with maximum Theta (K) of 0.35 degrees and 0.55 degrees at about 2.1 eV for CeAl2 and PrAl2, respectively. The evaluated off-diagonal conductivity spectra of the two compounds are also similar, with two structures at about 2.1 and 3.8 eV for CeAl2 and 2.1 and 3.4 eV for PrAl2. The energy difference in the second structures is interpreted as due to the different conduction-band structures of the two compounds caused by different hybridization strengths of their f states with conduction bands, because of the difference in their degree of localization. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Konkuk Univ, Dept Phys, Seoul 143701, South Korea. RP Lynch, DW (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. EM dwl@ameslab.gov RI Canfield, Paul/H-2698-2014 NR 37 TC 2 Z9 2 U1 1 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 JAN 15 PY 2001 VL 63 IS 3 AR 035105 PG 8 WC Physics, Condensed Matter SC Physics GA 395YJ UT WOS:000166608600037 ER PT J AU Le Bolloc'h, D Robertson, JL Reichert, H Moss, SC Crow, ML AF Le Bolloc'h, D Robertson, JL Reichert, H Moss, SC Crow, ML TI X-ray and neutron scattering study of Si-rich Si-Ge single crystals SO PHYSICAL REVIEW B LA English DT Article ID PHONON-DISPERSION RELATIONS; EPITAXIAL LAYERS; GERMANIUM; SILICON; GROWTH; ALLOYS; STRAIN; FILMS; ORDER; HETEROSTRUCTURES AB The local atomic environments of homogeneous Si-rich Si-Ge single crystals were studied using x-ray and neutron diffuse scattering. No evidence of either chemical short-range order or clustering was observed. Static atomic displacements, however, were clearly present and are consistent with an expansion of the lattice in the vicinity of the Ge atoms. The dispersion of the acoustic phonons was also measured using inelastic neutron scattering. The acoustic modes of the Si-Ge alloy were found to lie nearer those of pure Si than expected from the homologous relationship found between pure Si and pure Ge. C1 Univ Houston, Dept Phys, Houston, TX 77204 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Max Planck Inst Met Forsch, D-70569 Stuttgart, Germany. RP Le Bolloc'h, D (reprint author), European Synchrotron Radiat Facil, BP 220, F-38043 Grenoble, France. NR 58 TC 1 Z9 1 U1 1 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2001 VL 63 IS 3 AR 035204 PG 7 WC Physics, Condensed Matter SC Physics GA 395YJ UT WOS:000166608600046 ER PT J AU Lei, J Sun, H Yu, KW Louie, SG Cohen, ML AF Lei, J Sun, H Yu, KW Louie, SG Cohen, ML TI Image potential states on periodically corrugated metal surfaces SO PHYSICAL REVIEW B LA English DT Article ID DISPERSION; CU(001) AB Image potential states (IPS's) on periodically stepped metal surfaces have been calculated within an impenetrable surface model. Band splittings and band anticrossings are predicted for IPS's caused by the lateral back scatterings of the stepped surfaces. A reduction in the binding energy of the lowest IPS's was found due to the lateral confinement, which agrees fairly well with the experimental results. The calculated photoionization transition-matrix elements show that the photoionization of the lowest-energy IPS's on the stepped metal surface is nearly the same as that on planar metal surfaces, while fur the high-energy IPS's the umklapp, process becomes important in the photoionization, giving rise to electron scattering in different directions. C1 Shanghai Jiao Tong Univ, Dept Phys, Shanghai 200030, Peoples R China. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Chinese Univ Hong Kong, Dept Phys, Shatin, Hong Kong, Peoples R China. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Sun, H (reprint author), Shanghai Jiao Tong Univ, Dept Phys, Shanghai 200030, Peoples R China. EM hong_sun@online.sh.cn RI Sun, Hong/O-1206-2015 NR 21 TC 8 Z9 8 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 JAN 15 PY 2001 VL 63 IS 4 AR 045408 DI 10.1103/PhysRevB.63.045408 PG 5 WC Physics, Condensed Matter SC Physics GA 398HJ UT WOS:000166750600074 ER PT J AU Nordstrom, L Wills, JM Andersson, PH Soderlind, P Eriksson, O AF Nordstrom, L Wills, JM Andersson, PH Soderlind, P Eriksson, O TI Spin-orbit coupling in the actinide elements: A critical evaluation of theoretical equilibrium volumes SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; CRYSTAL-STRUCTURES; LIGHT ACTINIDES; PLUTONIUM; METALS; TH AB The difficulty of converging the contribution of the spin-orbit interaction to the total energy within an ls basis in actinide electronic structure calculations is discussed in detail. In particular, it is demonstrated that the source of the poor convergence is the treatment of the actinide 6p states. The limitation of the standard approach to relativity in full potential methods is manifested in muffin-tin based methods by a dependence of the total energy on the choice of muffin-tin radius. Despite this limitation it is found that structural phase stabilities are not affected, nor are pressure induced phase transitions. In order to treat the relativistic spin-orbit coupling in as large a part of space as possible one should, in muffin-tin based calculations, use a radius that is touching, or near touching, for all calculated volumes. C1 Uppsala Univ, Dept Phys, Uppsala, Sweden. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87544 USA. Univ Calif Lawrence Livermore Natl Lab, Phys Directorate, Livermore, CA 94550 USA. RP Nordstrom, L (reprint author), Uppsala Univ, Dept Phys, Box 530, Uppsala, Sweden. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 24 TC 54 Z9 54 U1 2 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 JAN 15 PY 2001 VL 63 IS 3 AR 035103 DI 10.1103/PhysRevB.63.035103 PG 5 WC Physics, Condensed Matter SC Physics GA 395YJ UT WOS:000166608600035 ER PT J AU Pitarke, JM Eguiluz, AG AF Pitarke, JM Eguiluz, AG TI Jellium surface energy beyond the local-density approximation: Self-consistent-field calculations SO PHYSICAL REVIEW B LA English DT Article ID EXCHANGE-CORRELATION ENERGY; RANDOM-PHASE-APPROXIMATION; BOUNDED ELECTRON-GAS; GENERALIZED GRADIENT APPROXIMATION; WAVE-VECTOR ANALYSIS; THIN METAL-FILMS; FUNCTIONAL THEORY; RESPONSE FUNCTION; WORK-FUNCTIONS; MONTE-CARLO AB We report extensive self-consistent calculations of jellium surface energies by going beyond the local density approximation. The density-response function of a bounded free-electron gas is evaluated within the random-phase approximation, with use of self-consistent electron density profiles. The exchange-correlation energy is then obtained from an exact adiabatic fluctuation-dissipation formula. We also investigate quantum-size effects and the extrapolation of finite-slab calculations to the infinite-width limit. C1 Euskal Herriko Unibertsitatea, Zientzi Fak, Bilbao 48080, Basque Country, Spain. UPV, EHU, CSIRO, Donostia Int Phys Ctr, Donostia San Sebastian, Basque Country, Spain. UPV, EHU, CSIRO, Ctr Mixto, Donostia San Sebastian, Basque Country, Spain. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Euskal Herriko Unibertsitatea, Zientzi Fak, 644 Posta Kutxatila, Bilbao 48080, Basque Country, Spain. RI CSIC-UPV/EHU, CFM/F-4867-2012; Pitarke, Jose/C-8602-2009; DONOSTIA INTERNATIONAL PHYSICS CTR., DIPC/C-3171-2014 OI Pitarke, Jose/0000-0002-8253-8028; NR 46 TC 55 Z9 55 U1 0 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 JAN 15 PY 2001 VL 63 IS 4 AR 045116 DI 10.1103/PhysRevB.63.045116 PG 11 WC Physics, Condensed Matter SC Physics GA 398HJ UT WOS:000166750600028 ER PT J AU Schneider, HC Jahnke, F Koch, SW Tignon, J Hasche, T Chemla, DS AF Schneider, HC Jahnke, F Koch, SW Tignon, J Hasche, T Chemla, DS TI Polariton propagation in high quality semiconductors: Microscopic theory and experiment versus additional boundary conditions SO PHYSICAL REVIEW B LA English DT Article ID GAAS THIN-LAYERS; EXCITON-POLARITON; QUANTUM-WELLS; HISTORICAL MISTAKE; SPATIAL-DISPERSION; DENSITY-MATRIX; HALF-SPACE; QUANTIZATION; INTERFERENCE; SCATTERING AB Linear exciton-polariton propagation in semiconductors is analyzed using a microscopic theory. Numerical results are compared with various approximation schemes based on additional boundary conditions, and with phase-amplitude linear spectroscopy experiments in high-quality GaAs. A simultaneous description of the measured amplitude and phase of the transmitted electric field is only possible with the full model. C1 Univ Marburg, Dept Phys, D-35032 Marburg, Germany. Univ Marburg, Ctr Mat Sci, D-35032 Marburg, Germany. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Schneider, HC (reprint author), Univ Marburg, Dept Phys, D-35032 Marburg, Germany. RI Schneider, Hans Christian/B-9450-2009 OI Schneider, Hans Christian/0000-0001-7656-4919 NR 51 TC 33 Z9 34 U1 1 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2001 VL 63 IS 4 AR 045202 DI 10.1103/PhysRevB.63.045202 PG 17 WC Physics, Condensed Matter SC Physics GA 398HJ UT WOS:000166750600037 ER PT J AU Wei, SH Zhang, SB AF Wei, SH Zhang, SB TI First-principles study of cation distribution in eighteen closed-shell A(II)B(2)(III)O(4) and A(IV)B(2)(II)O(4) spinel oxides SO PHYSICAL REVIEW B LA English DT Article ID NONSTOICHIOMETRIC SOLID-SOLUTIONS; SPECIAL QUASIRANDOM STRUCTURES; MAGNESIUM ALUMINATE SPINEL; GRAIN-BOUNDARY MIGRATION; ELECTRONIC-STRUCTURE; ELECTRICAL-PROPERTIES; GROUND-STATE; LATTICE; DENSITY; ALLOYS AB Using a first-principles band-structure method, we have systematically studied the cation distribution in closed-shell A(II)B(2)(III)O(4) and A (B2O4)-B-IV-O-II spinels where the group-II atoms are Mg, Zn, and Cd, the group-III atoms are Al, Ga, and In, and the group-IV atoms are Si, Ge, and Sn. The total energies, the structural parameters, and the band gaps of these compounds in both normal and inverse spinel structures are calculated. Compared with previous model studies, we show that an atomistic method is crucial to correctly identify the stability of the spinels and to calculate the anion displacement parameter u. The preference of cations with delocalized valence d states (e.g., Zn) to form covalent tetrahedral bonds also plays a significant role in determining the cation distribution in the spinels. Furthermore, the electronic structures of these spinel compounds depend strongly on the cation distribution. For most of the spinels studied here, the calculated band gaps for the inverse spinels are smaller than the corresponding normal spinels except for (SnB2O4)-O-II. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 52 TC 113 Z9 115 U1 1 U2 25 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2001 VL 63 IS 4 AR 045112 DI 10.1103/PhysRevB.63.045112 PG 8 WC Physics, Condensed Matter SC Physics GA 398HJ UT WOS:000166750600024 ER PT J AU Woicik, JC Nelson, EJ Kendelewicz, T Pianetta, P Jain, M Kronik, L Chelikowsky, JR AF Woicik, JC Nelson, EJ Kendelewicz, T Pianetta, P Jain, M Kronik, L Chelikowsky, JR TI Partial density of occupied valence states by x-ray standing waves and high-resolution photoelectron spectroscopy SO PHYSICAL REVIEW B LA English DT Article ID SURFACE-STRUCTURE DETERMINATION; ALLOYS; PSEUDOPOTENTIALS AB We introduce an experimental method by which sire-specific valence-electronic structure may be obtained. It utilizes the spatial dependence of the electric-field intensity that results from the superposition of the incident and reflected x-ray beams within the vicinity of a crystal x-ray Brag:: reflection. Resolution of the anion and cation contributions to the GaAs valence band is demonstrated and compared to an ab initio theoretical calculation of the Ga and As partial density of states. C1 Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. RP Woicik, JC (reprint author), Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RI Jain, Manish/A-8303-2010 OI Jain, Manish/0000-0001-9329-6434 NR 27 TC 14 Z9 14 U1 2 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 JAN 15 PY 2001 VL 63 IS 4 AR 041403 DI 10.1103/PhysRevB.63.041403 PG 4 WC Physics, Condensed Matter SC Physics GA 398HJ UT WOS:000166750600012 ER PT J AU Zhong, ZY Li, JH Kulik, J Chow, PC Norman, AG Mascarenhas, A Bai, J Golding, TD Moss, SC AF Zhong, ZY Li, JH Kulik, J Chow, PC Norman, AG Mascarenhas, A Bai, J Golding, TD Moss, SC TI Quadruple-period ordering along [110] in a GaAs0.87Sb0.13 alloy SO PHYSICAL REVIEW B LA English DT Article ID BEAM-EPITAXIAL-GROWTH; SEMICONDUCTORS; DIFFRACTION; MECHANISM; GAINP; PHASE AB A quantitative structural model, based on x-ray diffraction, is provided to analyze quadruple-period atomic ordering along [110] in a GaAs0.87Sb0.13 alloy grown on a (001) GaAs substrate by molecular beam epitaxy. To minimize the local strain energy derived by a valence force field (VFF) model for the alloy, atomic displacements were deduced and incorporated in our model. Calculation of the scattering pattern based on the model agrees well with experiment. We propose that this ordering originates from a (2X4) surface reconstruction and the difference in properties of the atomic species. C1 Univ Houston, Dept Phys, Houston, TX 77204 USA. Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Chinese Acad Sci, Inst Phys, Beijing 100080, Peoples R China. RP Zhong, ZY (reprint author), Univ Houston, Dept Phys, Houston, TX 77204 USA. RI Norman, Andrew/F-1859-2010; Bai, Jianming/O-5005-2015 OI Norman, Andrew/0000-0001-6368-521X; NR 25 TC 9 Z9 9 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 JAN 15 PY 2001 VL 63 IS 3 AR 033314 DI 10.1103/PhysRevB.63.033314 PG 4 WC Physics, Condensed Matter SC Physics GA 395YJ UT WOS:000166608600025 ER PT J AU Zuo, JK Zhang, TJ Wendelken, JF Zehner, DM AF Zuo, JK Zhang, TJ Wendelken, JF Zehner, DM TI Step bunching on TaC(910) due to attractive step-step interactions SO PHYSICAL REVIEW B LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; VICINAL SURFACES; TERRACE-WIDTH; SI(111); RECONSTRUCTION; TRANSITIONS AB Using scanning tunneling microscopy, we study the step configuration on TaC(910) which is vicinal to the (100) plane, miscut 6.34 degrees toward the [010] direction. After annealing at similar to 2100 degreesC, the surface is dominated by double-height steps which are bunched between relatively long intervening (100) terraces. The step-separation distribution is very skewed and sharply peaked. Monte Carlo simulations show that a strong, medium-range, repulsive step interaction A/x(2) must be combined with a weak, long-range, attractive interaction, -B/x(1.0+/-0.5) to fit the measured distribution. Possible physical origins for these interactions are discussed. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. SW Missouri State Univ, Dept Phys Astron & Mat Sci, Springfield, MO 65804 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Motorola Inc, SPS, Mesa, AZ 85202 USA. RP Zuo, JK (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 23 TC 2 Z9 2 U1 1 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 JAN 15 PY 2001 VL 63 IS 3 AR 033404 PG 4 WC Physics, Condensed Matter SC Physics GA 395YJ UT WOS:000166608600031 ER PT J AU Dalvit, DAR Dziarmaga, J Zurek, WH AF Dalvit, DAR Dziarmaga, J Zurek, WH TI Unconditional pointer states from conditional master equations SO PHYSICAL REVIEW LETTERS LA English DT Article ID DECOHERENCE; EINSELECTION AB When part of the environment responsible for decoherence is used to extract information about the decohering system, the preferred pointer states remain unchanged. This conclusion-reached for aspecific class of models-is investigated in a general setting of conditional master equations using suitable generalizations of predictability sieve. We also find indications that the einselected states are easiest to infer from the measurements carried out on the environment. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Jagiellonian Univ, Inst Phys, Krakow, Poland. RP Dalvit, DAR (reprint author), Los Alamos Natl Lab, Div Theoret, T-6,MS-B288, Los Alamos, NM 87545 USA. NR 14 TC 25 Z9 25 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 15 PY 2001 VL 86 IS 3 BP 373 EP 376 DI 10.1103/PhysRevLett.86.373 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400002 PM 11177834 ER PT J AU Kaplinghat, M Turner, MS AF Kaplinghat, M Turner, MS TI Precision cosmology and the density of baryons in the universe SO PHYSICAL REVIEW LETTERS LA English DT Article ID BIG-BANG NUCLEOSYNTHESIS AB Big-bang nucleosynthesis (BBN) and cosmic microwave background (CMB) anisotropy measurements give independent, accurate measurements of the baryon density and can test the framework of the standard cosmology. Early CMB data are consistent with the long-standing conclusion from BBN that baryons constitute a small fraction of matter in the Universe, but may indicate a slightly higher value for the baryon density. We clarify precisely what the two methods determine and point out that differing values for the baryon density can indicate either an inconsistency or physics beyond the standard models of cosmology and particle physics. We discuss other signatures of the new physics in CMB anisotropy. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Chicago, Dept Phys, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Kaplinghat, M (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 29 TC 29 Z9 29 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 15 PY 2001 VL 86 IS 3 BP 385 EP 388 DI 10.1103/PhysRevLett.86.385 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400005 PM 11177837 ER PT J AU Alavi-Harati, A Albuquerque, IF Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barker, AR Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Fordyce, PM Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hanagaki, K Hidaka, S Hsiung, YB Jejer, V Jennings, J Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL McManus, AP Mikelsons, P Monnier, E Nakaya, T Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Qiao, C Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Swanson, RA Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED AF Alavi-Harati, A Albuquerque, IF Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barker, AR Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Fordyce, PM Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hanagaki, K Hidaka, S Hsiung, YB Jejer, V Jennings, J Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL McManus, AP Mikelsons, P Monnier, E Nakaya, T Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Qiao, C Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Swanson, RA Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED CA KTeV Collaboration TI Search for the decay K-L -> pi(0)e(+)e(-) SO PHYSICAL REVIEW LETTERS LA English DT Article ID VECTOR-MESON EXCHANGE; BRANCHING RATIO AB We report on a search for the decay K-L --> pi (0)e(+)e(-) carried out by the KTeV/E799 experiment. at Fermilab. This decay is expected to have a significant CP violating contribution and the measurement of its branching ratio could support the Cabibbo-Kobayashi-Maskawa mechanism for CP violation or could point to new physics. Two events were observed in the 1997 data with an expected back ground of 1.06 +/- 0.41 events, and we set an upper limit B(K-L --> pi (0)e(+)e(-)) <5.1 X 10(-10) at the 90% confidence level. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Colorado, Boulder, CO 80309 USA. Elmurst Coll, Elmhurst, IL 60126 USA. Osaka Univ, Toyonaka, Osaka 560, Japan. Rice Univ, Houston, TX 77005 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. Univ Virginia, Inst Nucl & Particle Phys, Charlottesville, VA 22901 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Bellantoni, L (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. RI Albuquerque, Ivone/H-4645-2012 OI Albuquerque, Ivone/0000-0001-7328-0136 NR 25 TC 29 Z9 29 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 15 PY 2001 VL 86 IS 3 BP 397 EP 401 DI 10.1103/PhysRevLett.86.397 PG 5 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400008 PM 11177840 ER PT J AU Ackermann, KH Adams, N Adler, C Ahammed, Z Ahmad, S Allgower, C Amsbaugh, J Anderson, M Anderssen, E Arnesen, H Arnold, L Averichev, GS Baldwin, A Balewski, J Barannikova, O Barnby, LS Baudot, J Beddo, M Bekele, S Belaga, VV Bellwied, R Bennett, S Bercovitz, J Berger, J Betts, W Bichsel, H Bieser, F Bland, LC Bloomer, M Blyth, CO Boehm, J Bonner, BE Bonnet, D Bossingham, R Botlo, M Boucham, A Bouillo, N Bouvier, S Bradley, K Brady, FP Braithwaite, ES Braithwaite, W Brandin, A Brown, RL Brugalette, G Byrd, C Caines, H Sanchez, MCD Cardenas, A Carr, L Carroll, J Castillo, J Caylor, B Cebra, D Chatopadhyay, S Chen, ML Chen, W Chen, Y Chernenko, SP Cherney, M Chikanian, A Choi, B Chrin, J Christie, W Coffin, JP Conin, L Consiglio, C Cormier, TM Cramer, JG Crawford, HJ Danilov, VI Dayton, D DeMello, M Deng, WS Derevschikov, AA Dialinas, M Diaz, H DeYoung, PA Didenko, L Dimassimo, D Dioguardi, J Dominik, W Drancourt, C Draper, JE Dunin, VB Dunlop, JC Eckardt, V Edwards, WR Efimov, LG Eggert, T Emelianov, V Engelage, J Eppley, G Erazmus, B Etkin, A Fachini, P Feliciano, C Ferenc, D Ferguson, MI Fessler, H Finch, E Fine, V Fisyak, Y Flierl, D Flores, I Foley, KJ Fritz, D Gagunashvili, N Gans, J Gazdzicki, M Germain, M Geurts, F Ghazikhanian, V Gojak, C Grabski, J Grachov, O Grau, M Greiner, D Greiner, L Grigoriev, V Grosnick, D Gross, J Guilloux, G Gushin, E Hall, J Hallman, TJ Hardtke, D Harper, G Harris, JW He, P Heffner, M Heppelmann, S Herston, T Hill, D Hippolyte, B Hirsch, A Hjort, E Hoffmann, GW Horsley, M Howe, M Huang, HZ Humanic, TJ Hummler, H Hunt, W Hunter, J Igo, GJ Ishihara, A Ivanshin, YI Jacobs, P Jacobs, WW Jacobson, S Jared, R Jensen, P Johnson, I Jones, PG Judd, E Kaneta, M Kaplan, M Keane, D Kenney, VP Khodinov, A Klay, J Klein, SR Klyachko, A Koehler, G Konstantinov, AS Kormilitsyne, V Kotchenda, L Kotov, I Kovalenko, AD Kramer, M Kravtsov, P Krueger, K Krupien, T Kuczewski, P Kuhn, C Kunde, GJ Kunz, CL Kutuev, RK Kuznetsov, AA Lakehal-Ayat, L Lamas-Valverde, J Lamont, MAC Landgraf, JM Lange, S Lansdell, CP Lasiuk, B Laue, F Lebedev, A LeCompte, T Leonhardt, WJ Leontiev, VM Leszczynski, P LeVine, MJ Li, Q Li, Q Li, Z Liaw, CJ Lin, J Lindenbaum, SJ Lindenstruth, V Lindstrom, PJ Lisa, MA Liu, H Ljubicic, T Llope, WJ LoCurto, G Long, H Longacre, RS Lopez-Noriega, M Lopiano, D Love, WA Lutz, JR Lynn, D Madansky, L Maier, R Majka, R Maliszewski, A Margetis, S Marks, K Marstaller, R Martin, L Marx, J Matis, HS Matulenko, YA Matyushevski, EA McParland, C McShane, TS Meier, J Melnick, Y Meschanin, A Middlekamp, P Mikhalin, N Miller, B Milosevich, Z Minaev, NG Minor, B Mitchell, J Mogavero, E Moiseenko, VA Moltz, D Moore, CF Morozov, V Morse, R de Moura, MM Munhoz, MG Mutchler, GS Nelson, JM Nevski, P Ngo, T Nguyen, M Nguyen, T Nikitin, VA Nogach, LV Noggle, T Norman, B Nurushev, SB Nussbaum, T Nystrand, J Odyniec, G Ogawa, A Ogilvie, CA Olchanski, K Oldenburg, M Olson, D Ososkov, GA Ott, G Padrazo, D Paic, G Pandey, SU Panebratsev, Y Panitkin, SY Pavlinov, AI Pawlak, T Pentia, M Perevotchikov, V Peryt, W Petrov, VA Pinganaud, W Pirogov, S Platner, E Pluta, J Polk, I Porile, N Porter, J Poskanzer, AM Potrebenikova, E Prindle, D Pruneau, C Puskar-Pasewicz, J Rai, G Rasson, J Ravel, O Ray, RL Razin, SV Reichhold, D Reid, J Renfordt, RE Retiere, F Ridiger, A Riso, J Ritter, HG Roberts, JB Roehrich, D Rogachevski, OV Romero, JL Roy, C Russ, D Rykov, V Sakrejda, I Sanchez, R Sandler, Z Sandweiss, J Sappenfield, P Saulys, AC Savin, I Schambach, J Scharenberg, RP Scheblien, J Scheetz, R Schlueter, R Schmitz, N Schroeder, LS Schulz, M Schuttauf, A Sedlmeir, J Seger, J Seliverstov, D Seyboth, J Seyboth, P Seymour, R Shakaliev, EI Shestermanov, KE Shi, Y Shimanskii, SS Shuman, D Shvetcov, VS Skoro, G Smirnov, N Smykov, LP Snellings, R Solberg, K Sowinski, J Spinka, HM Srivastava, B Stephenson, EJ Stock, R Stolpovsky, A Stone, N Stone, R Strikhanov, M Stringfellow, B Stroebele, H Struck, C Suaide, AAP Sugarbaker, E Suire, C Symons, TJM Takahashi, J Tang, AH Tarchini, A Tarzian, J Thomas, JH Tikhomirov, V de Toledo, AS Tonse, S Trainor, T Trentalange, S Tokarev, M Tonjes, MB Trofimov, V Tsai, O Turner, K Ullrich, T Underwood, DG Vakula, I Van Buren, G VanderMolen, AM Vanyashin, A Vasilevski, IM Vasiliev, AN Vigdor, SE Visser, G Voloshin, SA Vu, C Wang, F Ward, H Weerasundara, D Weidenbach, R Wells, R Wells, R Wenaus, T Westfall, GD Whitfield, JP Whitten, C Wieman, H Willson, R Wilson, K Wirth, J Wisdom, J Wissink, SW Witt, R Wolf, J Wood, L Xu, N Xu, Z Yakutin, AE Yamamoto, E Yang, J Yepes, P Yokosawa, A Yurevich, VI Zanevski, YV Zhang, J Zhang, WM Zhu, J Zimmerman, D Zoulkarneev, R Zubarev, AN AF Ackermann, KH Adams, N Adler, C Ahammed, Z Ahmad, S Allgower, C Amsbaugh, J Anderson, M Anderssen, E Arnesen, H Arnold, L Averichev, GS Baldwin, A Balewski, J Barannikova, O Barnby, LS Baudot, J Beddo, M Bekele, S Belaga, VV Bellwied, R Bennett, S Bercovitz, J Berger, J Betts, W Bichsel, H Bieser, F Bland, LC Bloomer, M Blyth, CO Boehm, J Bonner, BE Bonnet, D Bossingham, R Botlo, M Boucham, A Bouillo, N Bouvier, S Bradley, K Brady, FP Braithwaite, ES Braithwaite, W Brandin, A Brown, RL Brugalette, G Byrd, C Caines, H Sanchez, MCD Cardenas, A Carr, L Carroll, J Castillo, J Caylor, B Cebra, D Chatopadhyay, S Chen, ML Chen, W Chen, Y Chernenko, SP Cherney, M Chikanian, A Choi, B Chrin, J Christie, W Coffin, JP Conin, L Consiglio, C Cormier, TM Cramer, JG Crawford, HJ Danilov, VI Dayton, D DeMello, M Deng, WS Derevschikov, AA Dialinas, M Diaz, H DeYoung, PA Didenko, L Dimassimo, D Dioguardi, J Dominik, W Drancourt, C Draper, JE Dunin, VB Dunlop, JC Eckardt, V Edwards, WR Efimov, LG Eggert, T Emelianov, V Engelage, J Eppley, G Erazmus, B Etkin, A Fachini, P Feliciano, C Ferenc, D Ferguson, MI Fessler, H Finch, E Fine, V Fisyak, Y Flierl, D Flores, I Foley, KJ Fritz, D Gagunashvili, N Gans, J Gazdzicki, M Germain, M Geurts, F Ghazikhanian, V Gojak, C Grabski, J Grachov, O Grau, M Greiner, D Greiner, L Grigoriev, V Grosnick, D Gross, J Guilloux, G Gushin, E Hall, J Hallman, TJ Hardtke, D Harper, G Harris, JW He, P Heffner, M Heppelmann, S Herston, T Hill, D Hippolyte, B Hirsch, A Hjort, E Hoffmann, GW Horsley, M Howe, M Huang, HZ Humanic, TJ Hummler, H Hunt, W Hunter, J Igo, GJ Ishihara, A Ivanshin, YI Jacobs, P Jacobs, WW Jacobson, S Jared, R Jensen, P Johnson, I Jones, PG Judd, E Kaneta, M Kaplan, M Keane, D Kenney, VP Khodinov, A Klay, J Klein, SR Klyachko, A Koehler, G Konstantinov, AS Kormilitsyne, V Kotchenda, L Kotov, I Kovalenko, AD Kramer, M Kravtsov, P Krueger, K Krupien, T Kuczewski, P Kuhn, C Kunde, GJ Kunz, CL Kutuev, RK Kuznetsov, AA Lakehal-Ayat, L Lamas-Valverde, J Lamont, MAC Landgraf, JM Lange, S Lansdell, CP Lasiuk, B Laue, F Lebedev, A LeCompte, T Leonhardt, WJ Leontiev, VM Leszczynski, P LeVine, MJ Li, Q Li, Q Li, Z Liaw, CJ Lin, J Lindenbaum, SJ Lindenstruth, V Lindstrom, PJ Lisa, MA Liu, H Ljubicic, T Llope, WJ LoCurto, G Long, H Longacre, RS Lopez-Noriega, M Lopiano, D Love, WA Lutz, JR Lynn, D Madansky, L Maier, R Majka, R Maliszewski, A Margetis, S Marks, K Marstaller, R Martin, L Marx, J Matis, HS Matulenko, YA Matyushevski, EA McParland, C McShane, TS Meier, J Melnick, Y Meschanin, A Middlekamp, P Mikhalin, N Miller, B Milosevich, Z Minaev, NG Minor, B Mitchell, J Mogavero, E Moiseenko, VA Moltz, D Moore, CF Morozov, V Morse, R de Moura, MM Munhoz, MG Mutchler, GS Nelson, JM Nevski, P Ngo, T Nguyen, M Nguyen, T Nikitin, VA Nogach, LV Noggle, T Norman, B Nurushev, SB Nussbaum, T Nystrand, J Odyniec, G Ogawa, A Ogilvie, CA Olchanski, K Oldenburg, M Olson, D Ososkov, GA Ott, G Padrazo, D Paic, G Pandey, SU Panebratsev, Y Panitkin, SY Pavlinov, AI Pawlak, T Pentia, M Perevotchikov, V Peryt, W Petrov, VA Pinganaud, W Pirogov, S Platner, E Pluta, J Polk, I Porile, N Porter, J Poskanzer, AM Potrebenikova, E Prindle, D Pruneau, C Puskar-Pasewicz, J Rai, G Rasson, J Ravel, O Ray, RL Razin, SV Reichhold, D Reid, J Renfordt, RE Retiere, F Ridiger, A Riso, J Ritter, HG Roberts, JB Roehrich, D Rogachevski, OV Romero, JL Roy, C Russ, D Rykov, V Sakrejda, I Sanchez, R Sandler, Z Sandweiss, J Sappenfield, P Saulys, AC Savin, I Schambach, J Scharenberg, RP Scheblien, J Scheetz, R Schlueter, R Schmitz, N Schroeder, LS Schulz, M Schuttauf, A Sedlmeir, J Seger, J Seliverstov, D Seyboth, J Seyboth, P Seymour, R Shakaliev, EI Shestermanov, KE Shi, Y Shimanskii, SS Shuman, D Shvetcov, VS Skoro, G Smirnov, N Smykov, LP Snellings, R Solberg, K Sowinski, J Spinka, HM Srivastava, B Stephenson, EJ Stock, R Stolpovsky, A Stone, N Stone, R Strikhanov, M Stringfellow, B Stroebele, H Struck, C Suaide, AAP Sugarbaker, E Suire, C Symons, TJM Takahashi, J Tang, AH Tarchini, A Tarzian, J Thomas, JH Tikhomirov, V de Toledo, AS Tonse, S Trainor, T Trentalange, S Tokarev, M Tonjes, MB Trofimov, V Tsai, O Turner, K Ullrich, T Underwood, DG Vakula, I Van Buren, G VanderMolen, AM Vanyashin, A Vasilevski, IM Vasiliev, AN Vigdor, SE Visser, G Voloshin, SA Vu, C Wang, F Ward, H Weerasundara, D Weidenbach, R Wells, R Wells, R Wenaus, T Westfall, GD Whitfield, JP Whitten, C Wieman, H Willson, R Wilson, K Wirth, J Wisdom, J Wissink, SW Witt, R Wolf, J Wood, L Xu, N Xu, Z Yakutin, AE Yamamoto, E Yang, J Yepes, P Yokosawa, A Yurevich, VI Zanevski, YV Zhang, J Zhang, WM Zhu, J Zimmerman, D Zoulkarneev, R Zubarev, AN CA STAR Collaboration TI Elliptic flow in Au plus Au collisions at root s(NN)=130 GeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID RELATIVISTIC NUCLEAR COLLISIONS; ANISOTROPIC FLOW; PHASE-TRANSITION; ENERGIES; SIGNATURE; QCD AB Elliptic flow from nuclear collisions is a hadronic observable sensitive to the early stages of system evolution. We report first results on elliptic flow of charged particles at midrapidity in Au + Au collisions at rootS(NN) = 130 GeV using the STAR Time Projection Chamber at the Relativistic Heavy Ion Collider. The elliptic flow signal, v(2), averaged over transverse momentum, reaches values of about 6% for relatively peripheral collisions and decreases for the more central collisions. This can be interpreted as the observation of a higher degree of thermalization than at lower collision energies. Pseudorapidity and transverse momentum dependence of elliptic how are also presented. C1 Max Planck Inst Phys, D-80805 Munich, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Arkansas, Little Rock, AR 72204 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Birmingham, Birmingham, W Midlands, England. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Creighton Univ, Omaha, NE 68178 USA. Joint Inst Nucl Res Dubna, Lab High Energy, Dubna, Russia. Joint Inst Nucl Res Dubna, Particle Phys Lab, Dubna, Russia. Univ Frankfurt, D-6000 Frankfurt, Germany. Indiana Univ, Bloomington, IN 47408 USA. Inst Rech Subatom, Strasbourg, France. Johns Hopkins Univ, Baltimore, MD 21218 USA. Kent State Univ, Kent, OH 44242 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Michigan State Univ, E Lansing, MI 48824 USA. Moscow Engn Phys Inst, Moscow 115409, Russia. CUNY City Coll, New York, NY 10031 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Ohio State Univ, Columbus, OH 43210 USA. Penn State Univ, University Pk, PA 16802 USA. Inst High Energy Phys, Protvino, Russia. Purdue Univ, W Lafayette, IN 47907 USA. Rice Univ, Houston, TX 77251 USA. Univ Sao Paulo, Sao Paulo, Brazil. SUBATECH, Nantes, France. Univ Texas, Austin, TX 78712 USA. Warsaw Univ, Warsaw, Poland. Warsaw Univ Technol, Warsaw, Poland. Univ Washington, Seattle, WA 98195 USA. Wayne State Univ, Detroit, MI 48201 USA. Yale Univ, New Haven, CT 06520 USA. RP Ackermann, KH (reprint author), Max Planck Inst Phys, D-80805 Munich, Germany. RI Tikhomirov, Vladimir/M-6194-2015; Suaide, Alexandre/L-6239-2016; KHODINOV, ALEKSANDR/D-6269-2015; Carr, Lincoln/E-3819-2016; Pentia, Mircea/B-2780-2011; Barnby, Lee/G-2135-2010; Takahashi, Jun/B-2946-2012; Chen, Yu/E-3788-2012; Witt, Richard/H-3560-2012; Castillo Castellanos, Javier/G-8915-2013; Vanyashin, Aleksandr/H-7796-2013; Voloshin, Sergei/I-4122-2013; Johnson, Ian/I-2439-2013; Skoro, Goran/P-1229-2014; Strikhanov, Mikhail/P-7393-2014; Ososkov, Gennady/B-8079-2016 OI Tikhomirov, Vladimir/0000-0002-9634-0581; Suaide, Alexandre/0000-0003-2847-6556; KHODINOV, ALEKSANDR/0000-0003-3551-5808; Carr, Lincoln/0000-0002-4848-7941; Barnby, Lee/0000-0001-7357-9904; Takahashi, Jun/0000-0002-4091-1779; Castillo Castellanos, Javier/0000-0002-5187-2779; Vanyashin, Aleksandr/0000-0002-0367-5666; Skoro, Goran/0000-0001-7745-9045; Strikhanov, Mikhail/0000-0003-2586-0405; Ososkov, Gennady/0000-0002-3223-6953 NR 28 TC 551 Z9 555 U1 2 U2 24 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 15 PY 2001 VL 86 IS 3 BP 402 EP 407 DI 10.1103/PhysRevLett.86.402 PG 6 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400009 PM 11177841 ER PT J AU Bolda, EL Chiao, RY Zurek, WH AF Bolda, EL Chiao, RY Zurek, WH TI Dissipative optical flow in a nonlinear Fabry-Perot cavity SO PHYSICAL REVIEW LETTERS LA English DT Article ID VORTEX FORMATION; EINSTEIN; BISTABILITY AB We describe a classical nonlinear optical system that displays superfluidity and its breakdown. The system consists of a self-defocusing refractive medium inside a Fabry-Perot cavity with a cylindrical obstacle. We have numerically solved for the transmitted beam when an incident plane wave strikes the cavity at an oblique angle. The presence of the incident beam pins the steady-state phase of the output, preventing the formation of vortices or time-dependent flow. When the incident beam is switched off, a transient wake of moving optical vortices is produced. This is analogous to the breakdown of superfluidity above a critical velocity. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bolda, EL (reprint author), Natl Inst Stand & Technol, Atom Phys Div, 100 Bur Dr,Stop 8423, Gaithersburg, MD 20899 USA. NR 21 TC 29 Z9 29 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 JAN 15 PY 2001 VL 86 IS 3 BP 416 EP 419 DI 10.1103/PhysRevLett.86.416 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400012 PM 11177844 ER PT J AU Fuchs, J Labaune, C Depierreux, S Baldis, HA Michard, A James, G AF Fuchs, J Labaune, C Depierreux, S Baldis, HA Michard, A James, G TI Experimental evidence of plasma-induced incoherence of an intense laser beam propagating in an underdense plasma SO PHYSICAL REVIEW LETTERS LA English DT Article ID SCALE-LENGTH PLASMAS; FILAMENTATION; SCATTERING AB Time dependent large angular spreading and spectral broadening of an intense randomized laser beam propagating in an underdense, well-characterized plasma is measured. The two features are correlated and increase with laser intensity or plasma density. This spatial and temporal incoherence imposed upon the beam via the coupling with the plasma is interpreted, in agreement with recent numerical simulations, as due to the interplay between dynamical filamentation and strongly driven stimulated Brillouin forward scattering. C1 Univ Paris 06, CNRS, UMR 7605,Lab Utilisat Lasers Intenses, CEA,Ecole Polytech, F-91128 Palaiseau, France. Univ Calif Lawrence Livermore Natl Lab, ILSA, Livermore, CA 94550 USA. RP Fuchs, J (reprint author), Univ Paris 06, CNRS, UMR 7605,Lab Utilisat Lasers Intenses, CEA,Ecole Polytech, F-91128 Palaiseau, France. RI Fuchs, Julien/D-3450-2016 OI Fuchs, Julien/0000-0001-9765-0787 NR 19 TC 26 Z9 26 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 15 PY 2001 VL 86 IS 3 BP 432 EP 435 DI 10.1103/PhysRevLett.86.432 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400016 PM 11177848 ER PT J AU Roth, M Cowan, TE Key, MH Hatchett, SP Brown, C Fountain, W Johnson, J Pennington, DM Snavely, RA Wilks, SC Yasuike, K Ruhl, H Pegoraro, F Bulanov, SV Campbell, EM Perry, MD Powell, H AF Roth, M Cowan, TE Key, MH Hatchett, SP Brown, C Fountain, W Johnson, J Pennington, DM Snavely, RA Wilks, SC Yasuike, K Ruhl, H Pegoraro, F Bulanov, SV Campbell, EM Perry, MD Powell, H TI Fast ignition by intense laser-accelerated proton beams SO PHYSICAL REVIEW LETTERS LA English DT Article ID FUSION; FUEL AB The concept of fast ignition with inertial confinement fusion (ICF) is a way to reduce the energy required for ignition and burn and to maximize the gain produced by a single implosion. Based on recent experimental findings at the PETAWATT laser at Lawrence Livermore National Laboratory, an intense proton beam to achieve fast ignition is proposed. It is produced by direct laser acceleration and focused onto the pellet from the rear side of an irradiated target and can be integrated into a hohlraum for indirect drive ICF. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Gesellsch Schwerionenforsch, Darmstadt, Germany. Gen Atom Co, San Diego, CA 92186 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Osaka Univ, ILE, Suita, Osaka 565, Japan. Max Born Inst, Berlin, Germany. Ist Nazl Fis Mat, Sez A, Pisa, Italy. RAS, Inst Gen Phys, Moscow 117901, Russia. RP Roth, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Bulanov, Sergei/A-1721-2013; Cowan, Thomas/A-8713-2011; OI Cowan, Thomas/0000-0002-5845-000X; Pegoraro, Francesco/0000-0002-7216-5491 NR 16 TC 785 Z9 821 U1 14 U2 75 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 15 PY 2001 VL 86 IS 3 BP 436 EP 439 DI 10.1103/PhysRevLett.86.436 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400017 PM 11177849 ER PT J AU Yoo, CS Iota, V Cynn, H AF Yoo, CS Iota, V Cynn, H TI Nonlinear carbon dioxide at high pressures and temperatures SO PHYSICAL REVIEW LETTERS LA English DT Article ID SOLID OXYGEN; CO2; PHASE; GPA AB A nonlinear molecular carbon dioxide phase IV was discovered by laser heating CO2-III (Cmca) between 12 and 30 GPa, followed by quenching to 300 K. The Raman spectrum of quenched CO2-IV exhibits a triplet bending mode v(2)(O = C = O) near 650 cm(-1), suggesting a broken inversion symmetry because of bending. The 650 cm(-1) bending modes soften with increasing pressure, indicating an enhanced intermolecular interaction among neighboring bent CO2 molecules. At 80 GPa, the low-frequency vibron collapses into high-frequency phonons, and CO2-IV becomes an extended amorphous solid. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Yoo, CS (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 21 TC 47 Z9 49 U1 0 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 JAN 15 PY 2001 VL 86 IS 3 BP 444 EP 447 DI 10.1103/PhysRevLett.86.444 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400019 PM 11177851 ER PT J AU Ozolins, V Asta, M AF Ozolins, V Asta, M TI Large vibrational effects upon calculated phase boundaries in Al-Sc SO PHYSICAL REVIEW LETTERS LA English DT Article ID DISORDERED NI3AL; 1ST-PRINCIPLES COMPUTATION; ENTROPY; PSEUDOPOTENTIALS; ALLOYS; STABILITY AB The fee portion of the AI-Sc phase diagram is calculated from first principles including contributions to alloy foe energies associated with ionic vibrations. It is found that vibrational entropy accounts for a 27-fold increase in the calculated solubility limits for Sc in fee Al at high temperatures, bringing calculated and measured values into very good agreement. The present work gives a clear example demonstrating a large effect of vibrational entropy upon calculated phase boundaries in substitutional alloys. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RP Ozolins, V (reprint author), Sandia Natl Labs, MS 9161,POB 969, Livermore, CA 94551 USA. RI Ozolins, Vidvuds/D-4578-2009 NR 21 TC 82 Z9 83 U1 3 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 15 PY 2001 VL 86 IS 3 BP 448 EP 451 DI 10.1103/PhysRevLett.86.448 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400020 PM 11177852 ER PT J AU Grossman, JC Rohlfing, M Mitas, L Louie, SG Cohen, ML AF Grossman, JC Rohlfing, M Mitas, L Louie, SG Cohen, ML TI High accuracy many-body calculational approaches for excitations in molecules SO PHYSICAL REVIEW LETTERS LA English DT Article ID MONTE-CARLO; ELECTRON CORRELATION; STRUCTURAL-PROPERTIES; BAND-GAPS; SEMICONDUCTORS; INSULATORS; ENERGIES; CLUSTERS; STATE AB Two state-of-the-art computational approaches: quantum Monte Carlo and GW with exciton effects [GW-BSE (Bethe-Salpeter equation)] are employed to calculate ionization potentials, electron affinities, and first excited singlet and triplet energies for the silane and methane molecules. Results are in excellent agreement between these dramatically different approaches and with available experiment. The optically forbidden triplet excitation in silane is predicted to lie roughly 1 eV higher than previously reported. In the GW-BSE method, we demonstrate that inclusion of off-diagonal matrix elements in the self-energy operator is crucial for an accurate picture. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Munster, Inst Theoret Phys Festkorperphys 2, D-48149 Munster, Germany. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Illinois, Natl Ctr Supercomp Applicat, Urbana, IL 61801 USA. RP Grossman, JC (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave,L-415, Livermore, CA 94550 USA. NR 24 TC 137 Z9 137 U1 2 U2 20 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 15 PY 2001 VL 86 IS 3 BP 472 EP 475 DI 10.1103/PhysRevLett.86.472 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400026 PM 11177858 ER PT J AU Wosnitza, J Wanka, S Hagel, J von Lohneysen, H Qualls, JS Brooks, JS Balthes, E Schlueter, JA Geiser, U Mohtasham, J Winter, RW Gard, GL AF Wosnitza, J Wanka, S Hagel, J von Lohneysen, H Qualls, JS Brooks, JS Balthes, E Schlueter, JA Geiser, U Mohtasham, J Winter, RW Gard, GL TI Field-induced metal-insulator transition in a two-dimensional organic superconductor SO PHYSICAL REVIEW LETTERS LA English DT Article ID DEPENDENT MAGNETORESISTANCE OSCILLATIONS; QUANTUM OSCILLATIONS; MAGNETIC-FIELDS; FERMI-SURFACE; BETA''-(BEDT-TTF)(2)SF5CH2CF2SO3; BEHAVIOR; BETA''-(ET)(2)SF5CH2CF2SO3; KAPPA-(BEDT-TTF)(2)I-3; TRANSPORT; ANION AB The quasi-two-dimensional organic superconductor beta "-(BEDT-TTF)(2)SF5CH2CF2SO3 (T-c approximate to 4.4 K) shows very strong Shubnikov-de Haas (SdH) oscillations which are superimposed on a highly anomalous steady background magnetoresistance, Rb. Comparison with de Haas-van Alphen oscillations allows a reliable estimate of Rb which is crucial for the correct extraction of the SdH signal. At low temperatures and high magnetic fields insulating behavior evolves. The magnetoresistance data violate Kohler's rule, i.e., cannot be described within the framework of semiclassical transport theory, but converge onto a universal curve appropriate for dynamical scaling at a metal-insulator transition. C1 Univ Karlsruhe, Inst Phys, D-76128 Karlsruhe, Germany. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Max Planck Inst Festkorperforsch, Grenoble High Magnet Field Lab, F-38042 Grenoble, France. CNRS, F-38042 Grenoble, France. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Portland State Univ, Dept Chem, Portland, OR 97207 USA. RP Qualls, JS (reprint author), Univ Karlsruhe, Inst Phys, Kaiserstr 12, D-76128 Karlsruhe, Germany. NR 30 TC 31 Z9 31 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 JAN 15 PY 2001 VL 86 IS 3 BP 508 EP 511 DI 10.1103/PhysRevLett.86.508 PG 4 WC Physics, Multidisciplinary SC Physics GA 392GB UT WOS:000166402400035 PM 11177867 ER PT J AU Srivatsan, TS Ravi, BG Naruka, AS Riester, L Petraroli, M Sudarshan, TS AF Srivatsan, TS Ravi, BG Naruka, AS Riester, L Petraroli, M Sudarshan, TS TI The microstructure and hardness of molybdenum powders consolidated by plasma pressure compaction SO POWDER TECHNOLOGY LA English DT Article DE molybdenum; processing; microstructure; density; hardness ID MICROWAVE-ASSISTED PREPARATION; TUNGSTEN POWDERS; COMPOSITES; DENSITY AB Bulk molybdenum samples were prepared by consolidating molybdenum powders using the technique of plasma pressure compaction ((PC)-C-2). The specimens were obtained by consolidating the powder particles under conditions of pulse and no-pulse and at two different temperatures. Results reveal that pulsing of the powders prior to consolidation had little influence on microhardness when compared to the samples that were obtained by consolidating the powder particles under no-pulse. Both nanohardness and microhardness measurements revealed a marginal decrease with an increase in temperature of compaction. The influence of processing variables on microstructural development and hardness is presented and discussed. (C) 2001 Elsevier Science S.A. All rights reserved. C1 Univ Akron, Auburn Sci & Engn Ctr, Dept Mech Engn, Akron, OH 44325 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Mech Characterizat & Anal Grp, Oak Ridge, TN 37831 USA. Timken Co, Timken Res, Canton, OH 44706 USA. Mat Modificat Inc, Fairfax, VA 22031 USA. RP Srivatsan, TS (reprint author), Univ Akron, Auburn Sci & Engn Ctr, Dept Mech Engn, Akron, OH 44325 USA. NR 27 TC 24 Z9 26 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD JAN 15 PY 2001 VL 114 IS 1-3 BP 136 EP 144 DI 10.1016/S0032-5910(00)00285-0 PG 9 WC Engineering, Chemical SC Engineering GA 391RA UT WOS:000166367900020 ER EF