FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Springer, JB Colvin, ME Colvin, OM Ludeman, SM AF Springer, JB Colvin, ME Colvin, OM Ludeman, SM TI Isophosphoramide mustard and its mechanism of bisalkylation SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID PHOSPHORAMIDE MUSTARD; CYCLOPHOSPHAMIDE; PROTONATION; IFOSFAMIDE; METABOLITE; O-17; N-15 AB To investigate the mechanism(s) of bisalkylation by isophosphoramide mustard (IPM), IPM-beta,beta,beta',beta'-d(4) was synthesized and the products of its reaction with thiosulfate (at pD 7.0) were analyzed by NMR. By both H-1 and C-13 NMR, the distribution of deuterium in the products was consistent with bisalkylation through sequential aziridinyl intermediates [(NCH2CD2S):(NCD2CH2S) = 53:47]. Under the given reaction conditions, label scrambling as a result of thiosulfate acting as a leaving group was ruled out through control experiments. The data gave a calculated kinetic isotope effect of 0.97 per deuterium. For the initial aziridine species formed from IPM, ab initio quantum chemical calculations gave a hybridization value of sp(2.4-2.5) for each of the C-H bonds of the reaction centers, and this correlated with the observed inverse isotope effect. Other structure and bond order data were also determined for this aziridine intermediate and related compounds. C1 Duke Univ, Med Ctr, Dept Med, Durham, NC 27710 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Ludeman, SM (reprint author), Duke Univ, Med Ctr, Dept Med, Durham, NC 27710 USA. NR 27 TC 23 Z9 23 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD OCT 16 PY 1998 VL 63 IS 21 BP 7218 EP 7222 DI 10.1021/jo980546s PG 5 WC Chemistry, Organic SC Chemistry GA 130ZH UT WOS:000076550200017 ER PT J AU Ambrose, WP Semin, DJ Robbins, DL Van Orden, A Kashem, MA Hamilton, SA Nelson, RM Jett, JH Keller, RA AF Ambrose, WP Semin, DJ Robbins, DL Van Orden, A Kashem, MA Hamilton, SA Nelson, RM Jett, JH Keller, RA TI Detection system for reaction-rate analysis in a low-volume proteinase-inhibition assay SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID MOLECULES; ENZYME AB High-throughput screening of large combinatorial chemical libraries in biochemical assays will benefit from reduced reagent volume and increased speed of measurement. Standard assays typically are performed in 96-well microtiter plates having 200-mu L well volumes and up to an hour of incubation time. In this paper, we demonstrate a technique for precise and rapid measurement of the progress of an enzymatic reaction and its inhibition with reduced volume and time (for this work, the assay was mixed at the 200-mu L level and detected in 2-mu L volumes with minutes of total assay time). Directly measuring the enzyme activity in the small volume format yields a precise value for the median inhibitory concentration (IC50) of an inhibitor compound. The model assay is the endoproteolytic cleavage of a small fluorogenic peptide by human neutrophil collagenase (MMP-8). The fluorogenic peptide was labeled at one end with a UV/blue fluorophore (N-methylanthranilyl) and at the other end with a quencher (dinitrophenol). To generate inhibition data, a hydroxamate peptide analog inhibitor of collagenase, actinonin, was included in the reaction. The experiments were performed using ultraviolet laser illumination (325 nm wavelength) and parallel fluorescence detection by a cooled, charge-coupled-device camera system to increase sensitivity and speed. The assay volume was reduced to 2 mu L for data collection, and the total time for mixing incubation, and measurement was less than 6 min. For comparison to a standard format, the same assay was performed in a 96-well microtiter plate in 200 mu L using 30 min of incubation and measurement in a microtiter plate fluorimeter. Median inhibitory concentrations (IC50) for actinonin of 73 +/- 16 and 100 +/- 14 nM were obtained in with assay miniaturization and increases in throughput is a potential loss of precision and accuracy. Laser excitation and parallel detection of fluorescence is a promising approach far increased speed and reduced cost without loss of precision for proteinase inhibition assays. (C) 1998 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Amgen Inc, Newbury Park, CA 91320 USA. Amgen Inc, Boulder, CO 80301 USA. RP Ambrose, WP (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Van Orden, Alan/N-4219-2015 NR 11 TC 8 Z9 9 U1 1 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD OCT 15 PY 1998 VL 263 IS 2 BP 150 EP 157 DI 10.1006/abio.1998.2786 PG 8 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 129VB UT WOS:000076483800003 PM 9799526 ER PT J AU Ho, MK Wang, SJ Porter, MD AF Ho, MK Wang, SJ Porter, MD TI Electrosorption based modification of porous graphitic carbon: Use of electrochemically modulated liquid chromatography to create a chiral stationary phase for enantiomeric separations SO ANALYTICAL CHEMISTRY LA English DT Article ID CYCLODEXTRIN INCLUSION COMPLEXES; EXCHANGE CHROMATOGRAPHY; BETA-CYCLODEXTRIN; COLUMN; ELECTROCHROMATOGRAPHY; POLYANILINE; SELECTIVITY; AMINES; LAYER; ACIDS AB A novel approach for the modification of the separation capabilities of electrochemically modulated liquid chromatography is described. The basis of the approach derives from the electrosorption of an organic additive from the mobile phase onto a porous graphitic carbon (PGC) stationary phase, resulting in a new dimension in the ability to alter reversibly the chemical composition at the surface of the stationary phase. The viability of the approach is demonstrated by the enantiomeric separation of racemic mixtures of the pharmaceutical agents hexobarbital and mephenytoin. These separations are achieved by the electrosorption of the organic additive P-cyclodextrin to form a PGC surface that is coated with a chiral selector. Results indicate that changes in applied potential can not only manipulate the effectiveness of these separations but can also reverse the enantiomeric elution order. A general mechanism for these separations is proposed and the potential applicability of the strategy to other types of LC separations is briefly noted. C1 US DOE, Ames Lab, Dept Chem, Ames, IA 50011 USA. RP Porter, MD (reprint author), US DOE, Ames Lab, Dept Chem, Ames, IA 50011 USA. EM mporter@porter1.ameslab.gov NR 43 TC 14 Z9 14 U1 0 U2 3 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 OCT 15 PY 1998 VL 70 IS 20 BP 4314 EP 4319 DI 10.1021/ac980431o PG 6 WC Chemistry, Analytical SC Chemistry GA 129WV UT WOS:000076487800014 ER PT J AU Sturchio, NC Clausen, JL Heraty, LJ Huang, L Holt, BD Abrajano, TA AF Sturchio, NC Clausen, JL Heraty, LJ Huang, L Holt, BD Abrajano, TA TI Chlorine isotope investigation of natural attenuation of trichloroethene in an aerobic aquifer SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID WATER; EXTRACTION; CARBON AB Natural attenuation of chlorinated aliphatic hydrocarbons (CAHs) can be an important mechanism for groundwater remediation. it is difficult to determine the effectiveness of natural CAH attenuation from chemical analyses of groundwater samples because mixing, dispersion, and secondary reactions can mask the chemical evidence of attenuation. In this paper, we explore the application of stable chlorine isotope ratio measurements as a new tool for for evaluating natural attenuation of CAHs. We report stable isotope ratios of chlorine in both trichloroethene (ICE) and inorganic chloride in groundwater from an aerobic aquifer beneath an extensively contaminated industrial site, the Paducah Gaseous Diffusion Plant in western Kentucky. Variations in the concentrations and chlorine isotope ratios of TCE and chloride in the groundwater a re consistent with those expected from natural attenuation. These data support a model in which partial TCE degradation occurred in: relatively impermeable, clay-rich sediments above the aquifer, and little or no further degradation of TCE occurred within the aquifer. A record of changing conditions within the TCE source area can be inferred from the spatial variation of chlorine isotope ratios for TCE and chloride within the plume. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. Lockheed Martin Energy Serv Inc, Kevil, KY 42053 USA. RP Sturchio, NC (reprint author), Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NR 31 TC 80 Z9 88 U1 1 U2 14 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 OCT 15 PY 1998 VL 32 IS 20 BP 3037 EP 3042 DI 10.1021/es9802605 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 130NC UT WOS:000076525300001 ER PT J AU Lytle, CM Lytle, FW Yang, N Qian, JH Hansen, D Zayed, A Terry, N AF Lytle, CM Lytle, FW Yang, N Qian, JH Hansen, D Zayed, A Terry, N TI Reduction of Cr(VI) to Cr(III) by wetland plants: Potential for in situ heavy metal detoxification SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID RAY-ABSORPTION-SPECTRA; HEXAVALENT-CHROMIUM; DNA-DAMAGE; POTAMOGETON PECTINATUS; CONTAMINATED SOILS; IRON UPTAKE; PHYTOREMEDIATION; GLUTATHIONE; MECHANISM; CHROMATE AB Reduction of heavy metals in situ by plants may be a useful detoxification mechanism for phytoremediation. Using X-ray spectroscopy, we show that Eichhornia crassipes (water hyacinth), supplied with Cr(VI) in nutrient culture, accumulated nontoxic Cr(III) in root and shoot tissues. The reduction of Cr(VI) to Cr(III) appeared to occur in the fine lateral roots. The Cr(III) was subsequently translocated to leaf tissues. Extended X-ray absorption fine structure of Cr in leaf and petiole differed when compared to Cr in roots. In roots, Cr(III) was hydrated by water, but in petiole and more so in leaf, a portion of the Cr(III) may be bound to oxalate ligands. This suggests that E. crassipes detoxified Cr(VI) upon root uptake and transported a portion of the detoxified Cr to leaf tissues. Cr-rich crystalline structures were observed on the leaf surface. The chemical species of Cr in other plants, collected from wetlands that contained Cr(VI)-contaminated wastewater, was also found to be Cr(III). We propose that this plant-based reduction of Cr(VI) by E crassipes has the potential to be used for the in situ detoxification of Cr(VI)-contaminated wastestreams. C1 Univ Calif Berkeley, Dept Plant & Microbial Biol, Berkeley, CA 94720 USA. EXAFS Co, Pioche, NV 89043 USA. Sandia Natl Labs, Div 8714, Livermore, CA 94551 USA. RP Terry, N (reprint author), Univ Calif Berkeley, Dept Plant & Microbial Biol, 111 Koshland Hall, Berkeley, CA 94720 USA. EM nterry@nature.berkeley.edu NR 49 TC 190 Z9 200 U1 2 U2 45 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 OCT 15 PY 1998 VL 32 IS 20 BP 3087 EP 3093 DI 10.1021/es980089x PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 130NC UT WOS:000076525300008 ER PT J AU King, RB Bhattacharyya, NK Smith, HD Wiemers, KD AF King, RB Bhattacharyya, NK Smith, HD Wiemers, KD TI Redox potential monitoring as a method to control unwanted noble metal-catalyzed hydrogen generation from formic acid treatment of simulated nuclear waste media SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID NITRITE AB Simulants for the Hanford Waste Vitrification Plant feed containing the major nonradioactive components Al, Cd, Fe, Mn, Nd, Ni, Si, Zr, Na, CO32-, NO3-, and NO2- were used to study redox potential changes in reactions of formic acid at 90 degrees C catalyzed by the noble metals Ru, Ph, and/or Pd found in significant quantities in uranium fission products. Such reactions were monitored using gas chromatography to analyze the CO2, H-2, NO, and N2O in the gas phase and a redox electrode to follow redox potential changes as a function of time. In the initial phase of formic acid addition to nitrite-containing feed simulants, the redox potential of the reaction mixture rises typically to +400 mV relative to the Ag/AgCl electrode because of the generation of the moderately strongly oxidizing nitrous acid. No H-2 production occurs at this stage of the reaction as long as free nitrous acid is present. After all of the nitrous acid has been destroyed by reduction to N2O and NO and disproportionation to NO/NO3-, the redox potential decreases upon further formic acid addition. Hydrogen production typically begins to occur when the redox potential of the reaction mixture becomes more negative than the AS/ASCl electrode. The experiments outlined in this paper suggest the feasibility of controlling the production of H-2 by limiting the amount of formic acid used and monitoring the redox potential during formic acid treatment. C1 Univ Georgia, Dept Chem, Athens, GA 30602 USA. Pacific NW Lab, Richland, WA 99352 USA. RP King, RB (reprint author), Univ Georgia, Dept Chem, Athens, GA 30602 USA. NR 9 TC 4 Z9 4 U1 2 U2 9 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 OCT 15 PY 1998 VL 32 IS 20 BP 3178 EP 3184 DI 10.1021/es970951l PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 130NC UT WOS:000076525300022 ER PT J AU Fan, TWM Higashi, RM Lane, AN AF Fan, TWM Higashi, RM Lane, AN TI Biotransformations of selenium oxyanion by filamentous cyanophyte-dominated mat cultured from agricultural drainage waters SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID DIMETHYL SELENONE; FOOD-CHAIN; BACTERIA; BIOACCUMULATION; METABOLISM; SULFATE AB A filamentous cyanophyte-dominated mat was cultured from waters of a large agricultural drainage evaporation basin in California. This mat was active in volatilizing Se from selenite at 20-10000 mu g/L Se, which accounted for >60% of the Se loss from the medium. Up to 75% of the medium Se was depleted over a 50-day period. This demonstrates a potentially important mechanism contributing to the nearly 100% loss of waterborne Se persistently observed at that basin. Se volatilization was via dimethylselenide, dimethyldiselenide, and dimethylselenenylsulfide, with evidence that the precursors were methylselenomethionine and methylselenocysteine but not dimethylselenonium propionate or trimethylselenonium ion. Selenite was also incorporated into proteins primarily in the form of selenomethionine at external Se concentrations of 5000 mu g/L Se or higher, which may account for the slow growth of the cyanophyte mat at these concentrations. Such Se metabolite characterization in aquatic producers is important for understanding the role of Se biogeochemistry in ecotoxicity, which is vital for development of environmentally sound in situ Se bioremediation. C1 Univ Calif Davis, Dept Land Air & Water Resources, Davis, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Crocker Nucl Lab, Livermore, CA 95616 USA. Natl Inst Med Res, Div Mol Struct, London NW7 1AA, England. RP Fan, TWM (reprint author), Univ Calif Davis, Dept Land Air & Water Resources, 1 Shields Ave, Davis, CA 95616 USA. NR 32 TC 37 Z9 38 U1 0 U2 1 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 OCT 15 PY 1998 VL 32 IS 20 BP 3185 EP 3193 DI 10.1021/es9708833 PG 9 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 130NC UT WOS:000076525300023 ER PT J AU Torres, MP Prange, C Lennon, G AF Torres, MP Prange, C Lennon, G TI Human endopeptidase 24.15 (THOP1) is localized on chromosome 19p13.3 and is excluded from the linkage region for late-onset Alzheimer disease SO GENOMICS LA English DT Article ID AMYLOID BETA-PROTEIN; BRAIN; RAT AB The mapping position of human endopeptidase 24.15 (THOP1) has previously been reported to be within the linkage region for the late-onset Alzheimer disease AD2 locus on chromosome 19q13.3. After localizing THOP1 to the high-resolution cosmid contig map of human chromosome 19, we found that the previous report was incorrect. Results of the hybridization and FISH mapping of positive clones indicated localization of THOP1 to chromosome 19p13.3 and not 19q13.3. This localization is a correction of wrong chromosomal delegation and excludes THOP1 from the region that shows evidence of linkage to late-onset familial Alzheimer disease. (C) 1998 Academic Press. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Program, Livermore, CA 94550 USA. RP Torres, MP (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Program, Livermore, CA 94550 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD OCT 15 PY 1998 VL 53 IS 2 BP 239 EP 240 DI 10.1006/geno.1998.5487 PG 2 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 132RN UT WOS:000076643700015 PM 9790774 ER PT J AU Li, XL Baker, DN Temerin, M Reeves, GD Belian, RD AF Li, XL Baker, DN Temerin, M Reeves, GD Belian, RD TI Simulation of dispersionless injections and drift echoes of energetic electrons associated with substorms SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PLASMA; PARTICLES; FIELDS; LINE; ION AB The term "dispersionless injection" refers to a class of events which show simultaneous enhancement (injection) of electrons and ions with different energies usually seen at or near geosynchronous orbit. We show that dispersionless injections can be understood as a consequence of changes in the electric and magnetic fields by modeling an electron injection event observed early on January 10, 1997 by means of a test-particle simulation. The model background magnetic field is a basic dipole field made asymmetrical by a compressed dayside and a weakened nightside. The transient fields are modeled with only one component of the electric field which is westward and a consistent magnetic field. These fields are used to model the major features of a dipolarization process during a substorm onset. We follow the electrons using a relativistic guiding center code. Our simulation results, with an initial kappa electron energy flux spectrum, reproduce the observed electron injection and subsequent drift echoes and show that the energization of injected electrons is mainly due to betatron acceleration of the preexisting electron population at larger radial distances in the magnetotail by transient fields. C1 Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Li, XL (reprint author), Univ Colorado, Atmospher & Space Phys Lab, 1234 Innovat Dr, Boulder, CO 80303 USA. OI Reeves, Geoffrey/0000-0002-7985-8098 NR 22 TC 139 Z9 141 U1 0 U2 9 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 OCT 15 PY 1998 VL 25 IS 20 BP 3763 EP 3766 DI 10.1029/1998GL900001 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 130CV UT WOS:000076502400006 ER PT J AU Caldeira, K Rau, GH Duffy, PB AF Caldeira, K Rau, GH Duffy, PB TI Predicted net efflux of radiocarbon from the ocean and increase in atmospheric radiocarbon content SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PAST 2 CENTURIES; CARBON-DIOXIDE; MODEL; CO2; DISSOCIATION; C-14; THERMODYNAMICS; DISTRIBUTIONS; SIMULATIONS; SEAWATER AB Prior to changes introduced by man, production of radiocarbon (C-14) in the stratosphere nearly balanced the flux of C-14 from the atmosphere to the ocean and land biosphere, which in turn nearly balanced radioactive decay in these C-14 reservoirs. This balance has been altered by land-use changes, fossil-fuel burning, and atmospheric nuclear detonations. Here, we use a model of the global carbon cycle to quantify these radiocarbon fluxes and make predictions about their magnitude in the future. Atmospheric nuclear detonations increased atmospheric C-14 content by about 80% by the mid-1960's. Since that time, the C-14 content of the atmosphere has been diminishing as this bomb radiocarbon has been entering the oceans and terrestrial biosphere. However, we predict that atmospheric C-14 content will reach a minimum and start to increase within the next few years if fossil-fuel burning continues according to a "business-as-usual" scenario, even though fossil fuels are devoid of C-14. This will happen because fossil-fuel carbon diminishes the net flux of C-14 from the atmosphere to the oceans and land biosphere, forcing C-14 to accumulate in the atmosphere. Furthermore, the net flux of both bomb and natural C-14 into the ocean are predicted to continue to slow and then, in the middle of the next century, to reverse, so that there will be a net flux of C-14 from the ocean to the atmosphere. The predicted reversal of net C-14 fluxes into the ocean is a further example of human impacts on the global carbon cycle. C1 Lawrence Livermore Natl Lab, Climate Syst Modeling Grp, Livermore, CA 94550 USA. RP Caldeira, K (reprint author), Lawrence Livermore Natl Lab, Climate Syst Modeling Grp, 7000 E Ave,L-103, Livermore, CA 94550 USA. EM kenc@LLNL.gov RI Caldeira, Ken/E-7914-2011 NR 31 TC 14 Z9 14 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD OCT 15 PY 1998 VL 25 IS 20 BP 3811 EP 3814 DI 10.1029/1998GL900010 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 130CV UT WOS:000076502400019 ER PT J AU Rider, WJ AF Rider, WJ TI Filtering non-solenoidal modes in numerical solutions of incompressible flows SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS LA English DT Article DE filters; approximate projections; incompressible flow ID NAVIER-STOKES EQUATIONS; 2ND-ORDER PROJECTION METHOD AB Solving the incompressible Navier-Stokes equations requires special care if the velocity field is not discretely divergence-free. Approximate projection methods and many pressure Poisson equation methods fall into this category. The approximate projection operator does not dampen high frequency modes that represent a local decoupling of the velocity held. For robust behavior, filtering is necessary. This is especially true in two instances that were studied: long-term integrations and large density jumps. Projection-based filters and velocity-based filters are derived and discussed. A cell-centered velocity filter, in conjunction with a vertex-projection filter, was found to be the most effective in the widest range of cases. (C) 1998 John Wiley & Sons, Ltd. C1 Univ Calif Los Alamos Natl Lab, Hydrodynam Methods Grp, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. RP Rider, WJ (reprint author), Univ Calif Los Alamos Natl Lab, Hydrodynam Methods Grp, Appl Theoret & Computat Phys Div, Mail Stop B265, Los Alamos, NM 87545 USA. NR 22 TC 6 Z9 6 U1 0 U2 0 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 OCT 15 PY 1998 VL 28 IS 5 BP 789 EP 814 DI 10.1002/(SICI)1097-0363(19981015)28:5<789::AID-FLD728>3.0.CO;2-4 PG 26 WC Computer Science, Interdisciplinary Applications; Mathematics, Interdisciplinary Applications; Mechanics; Physics, Fluids & Plasmas SC Computer Science; Mathematics; Mechanics; Physics GA 129VY UT WOS:000076485800002 ER PT J AU Zhao, YC Barvosa-Carter, W Theiss, SD Mitha, S Aziz, MJ Schiferl, D AF Zhao, YC Barvosa-Carter, W Theiss, SD Mitha, S Aziz, MJ Schiferl, D TI Pressure measurement at high temperature using ten Sm : YAG fluorescence peaks SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID DIAMOND-ANVIL CELL; CALIBRATION; SENSOR; SCALE; NITROGEN; SYSTEM; DEPENDENCE; DIFFUSION; VOLUME; RUBY AB A high-temperature pressure calibration technique using Sm-doped Y3Al5O12 (Sm:YAG) crystal as the pressure calibrant has been developed by studying its Y1 through Y10 fluorescence peaks (frequencies from 15 600 to 17 200 cm(-1)) at pressures (p) from 1 bar to 19 GPa and temperatures (T) from 20 to 850 degrees C in externally heated diamond anvil cells. The entire spectrum was fit to a sum of ten Lorentzians plus a linear background. The positions, relative intensities and widths were represented by empirical functions of p and T. Several fitting routines for p determination were created based on these dependences, and were tested on various high-p and high-T experimental Sm: YAG fluorescence spectra. The p values obtained from the fitting routines are compared with those obtained from the ruby and the nitrogen (N-2) vibron pressure scales. A fitting routine is proposed that can determine p from 20 to 850 degrees C within an estimated uncertainty of 0.4 GPa. (C) 1998 American Institute of Physics. [S0021-8979(98)06019-8]. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Zhao, YC (reprint author), Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RI Lujan Center, LANL/G-4896-2012 NR 21 TC 20 Z9 20 U1 1 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD OCT 15 PY 1998 VL 84 IS 8 BP 4049 EP 4059 DI 10.1063/1.368693 PG 11 WC Physics, Applied SC Physics GA 124MA UT WOS:000076185100003 ER PT J AU Leung, WY Tuttle, G Sigalas, MM Biswas, R Ho, KM Soukoulis, CM AF Leung, WY Tuttle, G Sigalas, MM Biswas, R Ho, KM Soukoulis, CM TI Optimizing the Q value in three-dimensional metallic photonic band gap crystals SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID FILTERS AB A metallic photonic band gap crystal with different defect structures is fabricated. The structure is designed and built to operate in the 8-26 GHz frequency range. Defects with sharp peaks in the transmission are created by removing portions of the metallic rods in a single defect layer. A high quality factor (Q) for the defect state is obtained by larger filling ratios and spatial separations between the unit cells. An optimized value of Q greater than or equal to 300 is found for three unit cell metallic photonic band gap structure. The experimental observations agree very well with theoretical calculations using the transfer matrix method. (C) 1998 American Institute of Physics. [S0021-8979(98)04320-5]. C1 Iowa State Univ, Microelect Res Ctr, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, USDOE, Ames, IA 50011 USA. RP Leung, WY (reprint author), Iowa State Univ, Microelect Res Ctr, Ames, IA 50011 USA. RI Soukoulis, Costas/A-5295-2008 NR 17 TC 11 Z9 11 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD OCT 15 PY 1998 VL 84 IS 8 BP 4091 EP 4095 DI 10.1063/1.368623 PG 5 WC Physics, Applied SC Physics GA 124MA UT WOS:000076185100010 ER PT J AU Xin, Y Browning, ND Rujirawat, S Sivananthan, S Chen, YP Nellist, PD Pennycook, SJ AF Xin, Y Browning, ND Rujirawat, S Sivananthan, S Chen, YP Nellist, PD Pennycook, SJ TI Investigation of the evolution of single domain, (111) B CdTe films by molecular beam epitaxy on miscut (001) Si substrate SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID POLARITY DETERMINATION; ELECTRON-DIFFRACTION; MISORIENTED SI(001); TWIN-FORMATION; DIRECT GROWTH; HGCDTE; SI(100); LAYER; TE; ORIENTATION AB A comprehensive view of the microstructure of (111)B CdTe films grown on miscut (001)Si substrates by molecular beam epitaxy has been obtained by transmission electron microscopy and scanning transmission electron microscopy. It is found that in the initial growth stage, CdTe nucleates with a dominance of one particular domain: a domain with (111)B polarity and orientation of [11-2]CdTe//[1-10]Si, although there are also some other domains of different polarity and orientation. The dominance of one type domain is due to the reduction of the surface symmetry by using the miscut substrate and by using optimum growth conditions. As the growth proceeds, a single-crystal film is produced by the dominating domain overgrowing the minority domains nucleated at the film-substrate interface. This results in the final film of single-crystal character having (111)B polarity with [11-2]CdTe along [1-10]Si. (C) 1998 American Institute of Physics. [S0021-8979(98)09220-2]. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Xin, Y (reprint author), Univ Illinois, Dept Phys, Chicago, IL 60607 USA. OI Browning, Nigel/0000-0003-0491-251X NR 29 TC 46 Z9 46 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD OCT 15 PY 1998 VL 84 IS 8 BP 4292 EP 4299 DI 10.1063/1.368647 PG 8 WC Physics, Applied SC Physics GA 124MA UT WOS:000076185100038 ER PT J AU Shan, W Walukiewicz, W Haller, EE Little, BD Song, JJ McCluskey, MD Johnson, NM Feng, ZC Schurman, M Stall, RA AF Shan, W Walukiewicz, W Haller, EE Little, BD Song, JJ McCluskey, MD Johnson, NM Feng, ZC Schurman, M Stall, RA TI Optical properties of InxGa1-xN alloys grown by metalorganic chemical vapor deposition SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TIME-RESOLVED PHOTOLUMINESCENCE; LIGHT-EMITTING-DIODES; INGAN QUANTUM-WELLS; ROOM-TEMPERATURE; LASER-DIODES; PRESSURE; EPILAYERS; HETEROSTRUCTURES; TRANSITIONS; ALXGA1-XAS AB We present the results of optical studies of the properties of InxGa1-xN epitaxial layers (02.0.CO;2 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 132CC UT WOS:000076611500001 ER PT J AU Subramanian, R McKamey, CG Schneibel, JH Buck, LR Menchhofer, PA AF Subramanian, R McKamey, CG Schneibel, JH Buck, LR Menchhofer, PA TI Iron aluminide Al2O3 composites by in situ displacement reactions: processing and mechanical properties SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE iron aluminide Al2O3 composites; in situ displacement reactions; mechanical properties ID ROOM-TEMPERATURE DUCTILITY; NICKEL-ALUMINIDE; SOLID-STATE; ALLOYS; FEAL; CHROMIUM; FE3AL AB Composites of an intermetallic alloy matrix (such as iron aluminide) and ceramic particle reinforcement (such as alumina) have potential for high-temperature structural applications requiring excellent oxidation resistance. In contrast to conventional processing methods (e.g. mechanical alloying), in situ processing techniques can be inexpensive and can also lead to unique microstructures, such as very fine dispersions of the reinforcements or interconnecting phases. The feasibility of processing Fe-Al alloy/Al2O3 composites by an in situ displacement reaction between Fe-40at.%Al and the iron oxide Fe2O3 was investigated and the results are presented in this paper. Specimens were prepared by hot pressing of the powder mixtures at 1300 degrees C. The final volume fractions of Al2O3 were determined by the initial ratio of Fe-40%Al to Fe2O3 and composites with 7 and 20 vol.% Al2O3 were investigated in this study. Compression creep tests performed at 700 degrees C showed that composites with 7 and 20 vol.% Al2O3 had higher compressive strengths than monolithic iron aluminide (Fe-28at.%Al). In particular, the compressive strength of the composite with 20 vol.% Al2O3 was three times that of the monolithic iron aluminide. Further increases in compressive strength, as well as significant improvements in bend and fracture strength, were obtained when the particle size of the starting Fe-40%Al powders was less than 10 mu m. Improved fracture toughness with the smaller Fe-40%Al powders could be attributed to the ductile failure of fine iron aluminide ligaments. The effect of Cr and Ti additions of up to 8 at.% on the strength of the interface between the iron aluminide and alumina phases was also investigated. The compressive strength of a composite processed with < 10-mu m diameter iron aluminide powders and 8 at.% Cr was the highest of all the specimens. However, within the range of compositions studied in this investigation, only slight improvements in the mechanical properties could be obtained with these alloying additions. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP McKamey, CG (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM mckameycg@ornl.gov RI Menchhofer, Paul/E-1529-2017 OI Menchhofer, Paul/0000-0001-9475-314X NR 44 TC 49 Z9 54 U1 2 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 EI 1873-4936 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD OCT 15 PY 1998 VL 254 IS 1-2 BP 119 EP 128 DI 10.1016/S0921-5093(98)00702-3 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 130LJ UT WOS:000076521300013 ER PT J AU Comolli, LR Pelton, JG Tinoco, I AF Comolli, LR Pelton, JG Tinoco, I TI Mapping of a protein-RNA kissing hairpin interface: Rom and Tar-Tar SO NUCLEIC ACIDS RESEARCH LA English DT Article ID HUMAN-IMMUNODEFICIENCY-VIRUS; COLE1 PLASMID REPLICATION; ANTISENSE RNA; CRYSTAL-STRUCTURE; BINDING DOMAIN; STEM-LOOPS; COMPLEX; NMR; RECOGNITION; SPECIFICITY AB An RNA 'kissing' complex is formed by the association of two hairpins via base pairing of their complementary loops, This sense-antisense RNA motif is used in the regulation of many cellular processes, including Escherichia coli ColE1 plasmid copy number, The RNA one modulator protein (Rom) acts as a co-regulator of ColE1 plasmid copy number by binding to the kissing hairpins and stabilizing their interaction. We have used heteronuclear two-dimensional NMR spectroscopy to map the interface between Rom and a kissing complex formed by the loop of the trans-activation response (Tar) element of immunodeficiency virus 1 (HIV-1) and its complement. The protein binding interface was obtained from changes in amide proton signals of uniformly N-15-labeled Rom with increasing concentrations of unlabeled Tar-Tar*. Similarly, the RNA-binding interface was obtained from changes in imino proton signals of uniformly N-15-labeled Tar with increasing concentrations of unlabeled Rom, Our results are in agreement with previous mutagenesis studies and provide additional information on Rom residues involved in RNA binding. The kissing hairpin interface with Rom leads to a model in which the protein contacts the minor groove of the loop-loop helix and, to a lesser extent, the major groove of the stems. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Biol Struct, Phys Biosci Div, Berkeley, CA 94720 USA. RP Tinoco, I (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM intinoco@lbl.gov FU NIGMS NIH HHS [GM 10840] NR 58 TC 28 Z9 28 U1 1 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD OCT 15 PY 1998 VL 26 IS 20 BP 4688 EP 4695 DI 10.1093/nar/26.20.4688 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 130VH UT WOS:000076540700020 PM 9753738 ER PT J AU Cai, L Chen, LQ Raghavan, S Ratliff, R Moyzis, R Rich, A AF Cai, L Chen, LQ Raghavan, S Ratliff, R Moyzis, R Rich, A TI Intercalated cytosine motif and novel adenine clusters in the crystal structure of the Tetrahymena telomere SO NUCLEIC ACIDS RESEARCH LA English DT Article ID DNA; RESOLUTION; RNA AB The cytosine-rich strand of the Tetrahymena telomere consists of multiple repeats of sequence d(AACCCC). We have solved the crystal structure of the crystalline repeat sequence at 2.5 Angstrom resolution. The adenines form two different and previously unknown clusters (A clusters) in orthogonal directions with their counterparts from other strands, each containing a total of eight adenines. The clusters appear to be stable aggregates held together by base stacking and three different base-pairing modes. Two different types of cytosine tetraplexes are found in the crystal. Each four-stranded complex is composed of two intercalated parallel-stranded duplexes pointing in opposite directions, with hemiprotonated cytosine-cytosine (C . C+) base pairs. The outermost C . C+ base pairs are from the 5'-end of each strand in one cytosine tetraplex and from the 3'-end of each strand in the other. The A clusters and the cytosine tetraplexes form two alternating stacking patterns, creating continuous base stacking in two perpendicular directions along the x- and z-axes. The adenine clusters could be organizational motifs for macromolecular RNA. C1 MIT, Dept Biol, Cambridge, MA 02139 USA. Univ Calif Los Alamos Natl Lab, Ctr Human Genome Studies, Los Alamos, NM 87545 USA. RP Rich, A (reprint author), MIT, Dept Biol, Room 68-233, Cambridge, MA 02139 USA. RI Chen, LongQing/I-7536-2012 OI Chen, LongQing/0000-0003-3359-3781 NR 24 TC 35 Z9 35 U1 0 U2 4 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD OCT 15 PY 1998 VL 26 IS 20 BP 4696 EP 4705 DI 10.1093/nar/26.20.4696 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 130VH UT WOS:000076540700021 PM 9753739 ER PT J AU Daimon, H Ynzunza, RX Palomares, FJ Tober, ED Wang, ZX Kaduwela, AP Van Hove, MA Fadley, CS AF Daimon, H Ynzunza, RX Palomares, FJ Tober, ED Wang, ZX Kaduwela, AP Van Hove, MA Fadley, CS TI Circular dichroism in core-level emission from O/W(110): Experiment and theory SO PHYSICAL REVIEW B LA English DT Article ID PHOTOELECTRON-DIFFRACTION; SPIN; LIGHT; SPACE; TIME AB Circular dichroism has been observed in the photoelectron diffraction of chemically shifted W 4f photoelectrons from the W(110)1 X 1-O surface. The diffraction peaks from first-layer W atoms bonded most directly to oxygen showed an azimuthal rotation similar to those reported in a prior experiment on Si(001). The maximum rotation angles are also in good agreement with those calculated using the formula Delta phi = m/kR sin(2) theta derived previously by Daimon et al. [Jpn. J. Appl. Phys., Part 2 32, L1480 (1993)] and assuming m = 4, which is the maximum magnetic quantum number of the photoelectron wave function. [S0163-1829(98)05139-X]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Nara Inst Sci & Technol, Grad Sch Mat Sci, Nara 6300101, Japan. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Daimon, H (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Van Hove, Michel/A-9862-2008; Palomares, Francisco Javier/C-4605-2011; OI Van Hove, Michel/0000-0002-8898-6921; Palomares, Francisco Javier/0000-0002-4768-2219; Kaduwela, Ajith/0000-0002-7236-2698 NR 15 TC 28 Z9 28 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 OCT 15 PY 1998 VL 58 IS 15 BP 9662 EP 9665 DI 10.1103/PhysRevB.58.9662 PG 4 WC Physics, Condensed Matter SC Physics GA 129WJ UT WOS:000076486800023 ER PT J AU Weinert, M Watson, RE AF Weinert, M Watson, RE TI Hybridization-induced band gaps in transition-metal aluminides SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; CHARGE-TRANSFER; SYSTEMS; AL2RU; FESI AB The occurrence of hybridization gaps around the Fermi level in ordered binary and ternary transition-metal aluminides is investigated using first-principles electronic structure calculations. Hybridization between transition-metal atoms and Al and the lack of transition-metal-Al d-d hybridization are both found to be important for the formation of the hollows or pseudogaps in the density of states. Whether these hollows become actual gaps, as predicted for RuAl2 FeAl2, and Fe2NbAl, depends on details of the electronic structure, including the relative positions of the atomic levels, the size of the atoms, the crystal structure, and the number of valence electrons. Although hybridization gaps resulting in true semiconductors are uncommon, at least among the aluminides, hollows in the density of states around the Fermi level are ubiquitous. [S0163-1829(98)08839-0]. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Weinert, M (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 19 TC 128 Z9 128 U1 5 U2 21 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 OCT 15 PY 1998 VL 58 IS 15 BP 9732 EP 9740 DI 10.1103/PhysRevB.58.9732 PG 9 WC Physics, Condensed Matter SC Physics GA 129WJ UT WOS:000076486800037 ER PT J AU Cervantes, P Williams, Q Cote, M Rohlfing, M Cohen, ML Louie, SG AF Cervantes, P Williams, Q Cote, M Rohlfing, M Cohen, ML Louie, SG TI Band structures of CsCl-structured BaS and CaSe at high pressure: Implications for metallization pressures of the alkaline earth chalcogenides SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; TRANSITION PRESSURES; PHASE-TRANSFORMATION; STATE; EQUATION; OXIDES; BATE; GAPS; WAVE; CELL AB The indirect energy gaps of CsCl-structured BaS and CaSe are measured at high pressures using absorption spectroscopy to pressures of 41 and 53 Cpa, respectively. Band-structure calculations using density-functional theory and quasiparticle corrections are also conducted on BaS and CaSe as a function of pressure. The measured indirect gaps of BaS and CaSe shift linearly with pressure with a slope, (dE(gap)/dP), of - 1.8(2) x 10(-2) and - 1.5(3)x 10(-2) eV/GPa, respectively. These values are in reasonable agreement with the theoretical results of - 2.2 x 10(-2) eV/GPa for BaS and - 2.3 x 10(-2) eV/GPa for CaSe. Our calculations indicate that the energy gap in both compounds is indirect with the valence-band maxima at M and the conduction-band minima at Gamma. Based;on a simple linear extrapolation of our data, we estimate the metallization pressures of CsCl-structured BaS and CaSe to be above 113 and 125 GPa, respectively. Our estimates of metallization pressures are compared with those of other alkaline earth monochalcogenides to determine the degree to which changes in the electronic structures of these compounds under pressure can be described using systematic trends based on ionic radii. [S0163-1829(98)03839-9]. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Washington State Univ, Dept Chem, Pullman, WA 99164 USA. RI Cote, Michel/H-3942-2012 OI Cote, Michel/0000-0001-9046-9491 NR 44 TC 21 Z9 21 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 OCT 15 PY 1998 VL 58 IS 15 BP 9793 EP 9800 DI 10.1103/PhysRevB.58.9793 PG 8 WC Physics, Condensed Matter SC Physics GA 129WJ UT WOS:000076486800045 ER PT J AU Watanabe, M Ootuka, Y Itoh, KM Haller, EE AF Watanabe, M Ootuka, Y Itoh, KM Haller, EE TI Electrical properties of isotopically enriched neutron-transmutation-doped Ge-70 : Ga near the metal-insulator transition SO PHYSICAL REVIEW B LA English DT Article ID CRITICAL CONDUCTIVITY EXPONENT; 3-DIMENSIONAL DISORDERED-SYSTEMS; CRITICAL-BEHAVIOR; SI-P; TEMPERATURE CONDUCTIVITY; NONZERO TEMPERATURES; ANDERSON TRANSITION; MAGNETIC-FIELD; LOCALIZATION; SEMICONDUCTORS AB We report low-temperature carrier transport properties of a series of nominally uncompensated neutron-transmutation-doped Ce-70:Ga samples very close to the critical concentration N-c for the metal-insulator transition. The nine samples closest to N-c have Ga concentrations N in the range 0.99N(c)N-c. The values of T-0 agree very well with theoretical estimates based on the modified Efros and Shklovskii relation k(B)T(0)approximate to(2.8e(2)/4 pi epsilon(0)kappa(0)xi(0))(1 - N/N-c)(alpha), where kappa(0) and xi(0) are the dielectric constant and the Bohr radius, respectively. The insulating samples very close to the transition (0.991N(c)1, so that the QPC has an inductive character, because of the predominant role of the open channels. In contrast, for N=0 or 1, for most values of the gate voltage, the imaginary Dart of the admittance is negative, corresponding to capacitive behavior. For gate voltages near values at which channels open or close, very strong nonlinear effects arise, and the admittance oscillates rapidly (with its imaginary part sometimes changing sign) both as the function of gate voltage (at fixed frequency) and as a function of frequency (at fixed gate voltage). Experimental observation of these oscillations would provide an important test of our semiclassical approach to the ac response of a QPC. We explore the low-frequency regime and investigate the extent to which one can understand the admittance in terms of a static conductance and a "quantum capacitance" and a "quantum inductance." We show that it is possible to choose the gate voltage so that there is a large, low-frequency regime in which the admittance is well approximated by a linear function of frequency. In this regime, the admittance can be treated by "equivalent circuit" concepts. We study how this approach breaks down at higher frequencies, where strongly nonlinear behavior of the admittance arises. We estimate the value of frequency, omega(c), at which the crossover from the low-frequency linear regime to the high-frequency nonlinear behavior occurs. For chosen parameters of a QPC, omega(c) approximate to 10 GHz. [S0163-1829(98)02339-X]. C1 Sage Technol Inc, Marietta, GA 30066 USA. Ukrainian Acad Sci, Inst Radiophys & Elect, UA-310085 Kharkov, Ukraine. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Sage Technol Inc, 1800 Sandy Plains Pkwy,Suite 320, Marietta, GA 30066 USA. NR 35 TC 17 Z9 17 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD OCT 15 PY 1998 VL 58 IS 15 BP 9894 EP 9906 DI 10.1103/PhysRevB.58.9894 PG 13 WC Physics, Condensed Matter SC Physics GA 129WJ UT WOS:000076486800059 ER PT J AU Shen, Z Kramer, MJ Jenks, CJ Goldman, AI Lograsso, T Delaney, D Heinzig, M Raberg, W Thiel, PA AF Shen, Z Kramer, MJ Jenks, CJ Goldman, AI Lograsso, T Delaney, D Heinzig, M Raberg, W Thiel, PA TI Crystalline surface structures induced by ion sputtering of Al-rich icosahedral quasicrystals SO PHYSICAL REVIEW B LA English DT Article ID QUASI-CRYSTAL; PHASE-TRANSFORMATION; PD-MN; ALLOYS; LEED; IRRADIATION; GROWTH AB Low-energy electron diffraction patterns, produced from quasicrystal surfaces by ion sputtering and annealing to temperatures below similar to 700 K, can be assigned to various terminations of the cubic CsCl structure. The assignments are based upon ratios of spot spacings, estimates of surface lattice constants, bulk phase diagrams vs surface compositions, and comparisons with previous work. The CsCl overlayers are deeper than about five atomic layers, because they obscure the diffraction spots from the underlying quasicrystalline substrate. These patterns transform irreversibly to quasicrystalline(like) patterns upon annealing to higher temperatures, indicating that the cubic overlayers are metastable. Based upon the data for three chemically identical, but symmetrically inequivalent surfaces, st model is developed for the relation between the cubic overlayers and the quasicrystalline substrate. The model is based upon the related symmetries of. cubic close-packed and icosahedral-packed materials. The model explains not only the symmetries of the cubic surface terminations, but also the number and orientation of domains. [S0163-1829(98)00239-2]. C1 Iowa State Univ, Ames Lab, DOE, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Thiel, PA (reprint author), Iowa State Univ, Ames Lab, DOE, Ames, IA 50011 USA. EM thiel@ameslab.gov NR 48 TC 87 Z9 89 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 OCT 15 PY 1998 VL 58 IS 15 BP 9961 EP 9971 DI 10.1103/PhysRevB.58.9961 PG 11 WC Physics, Condensed Matter SC Physics GA 129WJ UT WOS:000076486800067 ER PT J AU Harrison, N Mielke, CH Rickel, DG Wosnitza, J Qualls, JS Brooks, JS Balthes, E Schweitzer, D Heinen, I Strunz, W AF Harrison, N Mielke, CH Rickel, DG Wosnitza, J Qualls, JS Brooks, JS Balthes, E Schweitzer, D Heinen, I Strunz, W TI Quasi-two-dimensional spin-split Fermi-liquid behavior of kappa-(BEDT-TTF)(2)I-3 in strong magnetic fields SO PHYSICAL REVIEW B LA English DT Article ID HAAS-VAN-ALPHEN; ORGANIC SUPERCONDUCTOR KAPPA-(BEDT-TTF)(2)I-3; QUANTUM HALL REGIME; OSCILLATIONS; BREAKDOWN; ALPHA-(BEDT-TTF)(2)TLHG(SCN)(4); INTERFERENCE; CONDUCTORS; METAL AB Measurements of both the magnetization and magnetotransport of kappa-(BEDT-TTF)(2)I-3 (BEDT-TTF is bisethylenedithio-tetrathiafulvalene) in magnetic fields extending to 60 T at 0.4 K and 20 T at 35 mK are reported. Strong eddy currents observed in the magnetization are found to exhibit critical currentlike behavior. This might be connected with the breakdown of the quantum Hall effect, as proposed previously for alpha-phase salts. The strong two dimensionality leads to an apparent fall of the effective mass together with an overall suppression of the amplitude of the magnetic quantum oscillations at high magnetic fields or very low temperatures. These effects are more pronounced for the Shubnikov-de Haas (SdH) effect but clearly visible also for the de Haas-van Alphen (dHvA) oscillations. The apparent fall of the effective mass and the deviations of the dHvA signal from the behavior predicted by the standard Lifshitz-Kosevich theory can quantitatively be explained by the influence of chemical-potential oscillations on the wave form in a two-dimensional, spin-split Fermi liquid. The much stronger deviations from the conventional behavior in the transport data hint to an additional mechanism unique to the SdH effect. [S0163-1829(98)01940-7]. C1 Univ Calif Los Alamos Natl Lab, High Field Magnet Lab, Los Alamos, NM 87545 USA. Univ Karlsruhe, Inst Phys, D-76128 Karlsruhe, Germany. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Univ Stuttgart, Inst Phys 3, D-70550 Stuttgart, Germany. Univ Heidelberg, Inst Anorgan Chem, D-69120 Heidelberg, Germany. RP Univ Calif Los Alamos Natl Lab, High Field Magnet Lab, POB 1663, Los Alamos, NM 87545 USA. RI Mielke, Charles/S-6827-2016 OI Mielke, Charles/0000-0002-2096-5411 NR 34 TC 30 Z9 30 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 OCT 15 PY 1998 VL 58 IS 16 BP 10248 EP 10255 DI 10.1103/PhysRevB.58.10248 PG 8 WC Physics, Condensed Matter SC Physics GA 133ZB UT WOS:000076716500036 ER PT J AU Rozenberg, GK Milner, AP Pasternak, MP Hearne, GR Taylor, RD AF Rozenberg, GK Milner, AP Pasternak, MP Hearne, GR Taylor, RD TI Experimental confirmation of a p-p intraband gap in Sr2FeO4 SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-METAL COMPOUNDS; DIAMOND-ANVIL CELL; ELECTRONIC-STRUCTURE; MOSSBAUER-SPECTROSCOPY; HIGH-PRESSURES AB The electrical-transport, magnetic, and structural properties of the antiferromagnetic semiconductor Sr2FeO4(Fe4+,d(4)) have been probed by resistance, Fe-57 Mossbauer spectroscopy, and x-ray-diffraction measurements to similar to 30 GPa in a diamond-anvil cell. The pertinent results of this work are that a semiconductor-metal transition occurs at P(C)similar to 18(1) GPa, while the Fe(IV) 3d magnetic moments remain unaltered across the transition. To the highest pressure of 30 GPa, the relative volume of the unit cell decreases to V/V(0)similar to 0.82, with no structural symmetry modification of the K2NiF4-type unit cell. At and above P-C, a magnetic hyperfine spectrum comprised of a single component with a non-negligible quadrupole interaction is evident below spin-ordering temperatures Tn(h)=n(e) diagonal transitions initially and generates n(e)-->n(h)not equal n(e) off-diagonal transitions that are forbidden at B-parallel to=0. The intensities oscillate at higher B-parallel to. An additional electric field E-parallel to parallel to B-parallel to modifies the effective B-parallel to and introduces a magneto-Stark shift in the PL line. This new Stark shift requires B-parallel to not equal 0 unlike the ordinary Stark shift in perpendicular E-perpendicular to. [S0163-1829(98)51040-5]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 0 Z9 0 U1 0 U2 2 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 OCT 15 PY 1998 VL 58 IS 16 BP R10187 EP R10190 DI 10.1103/PhysRevB.58.R10187 PG 4 WC Physics, Condensed Matter SC Physics GA 133ZB UT WOS:000076716500025 ER PT J AU Shan, W Ager, JW Walukiewicz, W Haller, EE McCluskey, MD Johnson, NM Bour, DP AF Shan, W Ager, JW Walukiewicz, W Haller, EE McCluskey, MD Johnson, NM Bour, DP TI Pressure dependence of optical transitions in In0.15Ga0.85N/GaN multiple quantum wells SO PHYSICAL REVIEW B LA English DT Article ID SEMI-INSULATING GAAS; HYDROSTATIC-PRESSURE; GALLIUM NITRIDE; PHOTOREFLECTANCE; PHOTOLUMINESCENCE; GAN; SUPERLATTICES; TEMPERATURE; CONSTANTS; STATES AB The effects of hydrostatic pressure on optical transitions in In0.15Ga0.85N/GaN multiple quantum wells (MQW's) have been studied. The optical transition associated with confined electron and hole states in the MQW's was found to shift linearly to higher energy with pressure but exhibit a significantly weaker pressure dependence compared to bulklike thick epitaxial-layer samples. Similar pressure coefficients obtained by both photomodulation and photoluminescence measurements rule out the possibility of the transition involving localized states deep in the band gap. We found that the difference in the compressibility of InxGa1-xN and GaN induces a tensile strain in the compressively strained InxGa1-xN well layers, partially compensating the externally applied hydrostatic pressure. This mechanical effect is primarily responsible for the smaller pressure dependence of the optical transitions in the InxGa1-xN/GaN MQW's. In addition, the pressure-dependent measurements allow us to identify a spectral feature observed at an energy below the GaN band gap. We conclude that this feature is due to transitions from ionized Mg acceptor states to the conduction band in the p-type GaN cladding layer rather than a confined transition in the MQW's. [S0163-1829(98)51940-6]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Xerox Palo Alto Res Ctr, Palo Alto, CA 94304 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 31 TC 1 Z9 1 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD OCT 15 PY 1998 VL 58 IS 16 BP R10191 EP R10194 DI 10.1103/PhysRevB.58.R10191 PG 4 WC Physics, Condensed Matter SC Physics GA 133ZB UT WOS:000076716500026 ER PT J AU Laguna, P Zurek, WH AF Laguna, P Zurek, WH TI Critical dynamics of symmetry breaking: Quenches, dissipation, and cosmology SO PHYSICAL REVIEW D LA English DT Article ID STRING FORMATION; SUPERFLUID HE-3; LIQUID-CRYSTALS; ANALOG AB Symmetry-breaking phase transitions may leave behind topological defects with a density dependence on the quench rate. We investigate the dynamics of such quenches for the one-dimensional, Landau-Ginzburg case and show that the density of kinks, n, scales differently with the quench time scale, tau(Q), depending on whether the dynamics in the vicinity of the critical point is overdamped (n proportional to tau(Q)(-1/4)) or underdamped (n proportional to tau(Q)(-1/3)). Either of these cases may be relevant to the early Universe, and we derive bounds on the initial density of topological defects in cosmological phase transitions. [S0556-2821(98)01820-7]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Penn State Univ, CGPG, University Pk, PA 16802 USA. RP Laguna, P (reprint author), Univ Calif Los Alamos Natl Lab, MS-B288, Los Alamos, NM 87545 USA. NR 15 TC 55 Z9 55 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 OCT 15 PY 1998 VL 58 IS 8 AR 085021 DI 10.1103/PhysRevD.58.085021 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 130RW UT WOS:000076535000078 ER PT J AU Hoberg, JO AF Hoberg, JO TI Synthesis of seven-membered oxacycles SO TETRAHEDRON LA English DT Review ID MARINE NATURAL-PRODUCTS; BAEYER-VILLIGER OXIDATION; RING-CLOSING METATHESIS; INTRAMOLECULAR 1,3-DIPOLAR CYCLOADDITION; ACYL RADICAL CYCLIZATIONS; EEL GYMNOTHORAX-JAVANICUS; CYCLIC ETHERS; STEREOSELECTIVE SYNTHESIS; OLEFIN METATHESIS; MOLECULAR-OXYGEN C1 Victoria Univ Wellington, Sch Chem & Phys Sci, Wellington, New Zealand. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Hoberg, JO (reprint author), Victoria Univ Wellington, Sch Chem & Phys Sci, Wellington, New Zealand. EM John.Hoberg@vuw.ac.nz NR 198 TC 134 Z9 135 U1 2 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4020 J9 TETRAHEDRON JI Tetrahedron PD OCT 15 PY 1998 VL 54 IS 42 BP 12631 EP 12670 DI 10.1016/S0040-4020(98)00596-1 PG 40 WC Chemistry, Organic SC Chemistry GA 124JL UT WOS:000076179100001 ER PT J AU Cohen, JS AF Cohen, JS TI Fermion molecular dynamics in the capture of muons by hydrogen atoms SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Letter ID SEMICLASSICAL DESCRIPTION; ANTIPROTON CAPTURE; COLLISIONS; IONIZATION; HEISENBERG; HELIUM AB The fermion-molecular-dynamics (FMD) method is applied to negative-muon (mu(-)) capture by the hydrogen atom. It is found that the FMD results are similar to those of the classical-trajectory Monte Carlo (CTMC) method, whose validity was confirmed previously by the most accurate existing method, classical-quantal coupling (CQC). Thus FMD is validated as a quasiclassical method for mu(-) capture and will be applicable to multi-electron atomic and molecular targets, for which the CTMC approach is not suitable. Actually the FMD results agree slightly better with the CQC results and suggest an interpretation of the very low-energy and adiabatic-ionization-threshold regions where the quantal (CQC) cross sections differ most from the classical (CTMC) results. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Cohen, JS (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. EM cohen@lanl.gov NR 22 TC 15 Z9 15 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD OCT 14 PY 1998 VL 31 IS 19 BP L833 EP L840 DI 10.1088/0953-4075/31/19/011 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 131VX UT WOS:000076596900011 ER PT J AU Nicholas, JB Kheir, AA Xu, T Krawietz, TR Haw, JF AF Nicholas, JB Kheir, AA Xu, T Krawietz, TR Haw, JF TI Theoretical and solid-state NMR study of acetylene adsorption on nano-sized MgO SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID IN-SITU NMR; AB-INITIO; CHEMICAL-SHIFTS; PERTURBATION-THEORY; (MGO)(N) CLUSTERS; BASIS SET; OXIDE; MODEL; CHEMISORPTION; NITROMETHANE AB We present a combined density functional theory, gauge-including atomic orbital (GIAO), in situ C-13 MAS NMR, and in situ infrared study of acetylene adsorption on nano-sized MgO powder. Geometries were optimized using the hybrid B3LYP exchange-correlation functional and triple-zeta basis sets. By utilizing models of the surface ranging in size from Mg4O4 to Mg8O8, we optimized geometries for a variety of surface-bound species on corner and edges sites. No stable dissociation products on the flat, (100)-like surface of an Mg12O12 cluster could be obtained theoretically, in agreement with a previous ultrahigh vacuum surface science experiment. We also present GIAO-restricted Hartree-Fock predictions of the C-13 chemical shifts of all species and their vibrational frequencies. The agreement between theory and experiment is outstanding. Both the theoretical and experimental results strongly support the formation of an acetylide on the MgO surface, while an alternative vinylidene species is not present. A minority species was also observed, which both theory and experiment identify as an ethoxide. This work, the first combined theoretical and in situ NMR study of chemisorption on a (nonzeolitic) metal oxide surface, suggests that this approach will be very useful for the future study of catalytic phenomena on metal oxides. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Texas A&M Univ, Dept Chem, Ctr Catalysis, College Stn, TX 77843 USA. RP Nicholas, JB (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 40 TC 15 Z9 15 U1 0 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 OCT 14 PY 1998 VL 120 IS 40 BP 10471 EP 10481 DI 10.1021/ja980384h PG 11 WC Chemistry, Multidisciplinary SC Chemistry GA 129UK UT WOS:000076481900025 ER PT J AU Yan, SG Brunschwig, BS Creutz, C Fujita, E Sutin, N AF Yan, SG Brunschwig, BS Creutz, C Fujita, E Sutin, N TI Reversible formation of bis(2,2 '-bipyridine)rhodium(III) dihydrate from bis(2,2 '-bipyridine)rhodium(I) and dihydrogen. Direct transfer of dihydrogen from rhodium(III) dihydride to rhodium(I) SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID OXIDATIVE ADDITION; AQUEOUS-SOLUTION; COMPLEXES; GENERATION; H-2; MECHANISM; REDUCTION; IRIDIUM; LIGAND; RATES C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Brunschwig, BS (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Brunschwig, Bruce/G-4249-2011; Fujita, Etsuko/D-8814-2013 NR 40 TC 24 Z9 24 U1 0 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD OCT 14 PY 1998 VL 120 IS 40 BP 10553 EP 10554 DI 10.1021/ja982208e PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 129UK UT WOS:000076481900040 ER PT J AU Long, JR Dindot, JL Zebroski, H Kiihne, S Clark, RH Campbell, AA Stayton, PS Drobny, GP AF Long, JR Dindot, JL Zebroski, H Kiihne, S Clark, RH Campbell, AA Stayton, PS Drobny, GP TI A peptide that inhibits hydroxyapatite growth is in an extended conformation on the crystal surface SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID CALCIUM-PHOSPHATE PRECIPITATION; HUMAN SALIVARY STATHERIN; HUMAN-PAROTID SALIVA; ACID-RICH SEQUENCES; SOLID-STATE NMR; SHELL PROTEINS; MACROMOLECULES; PHOSPHOPROTEIN; MINERALIZATION; ORIENTATION AB Proteins play an important role in the biological mechanisms controlling hard tissue development, but the details of molecular recognition at inorganic crystal interfaces remain poorly characterized. We have applied a recently developed homonuclear dipolar recoupling solid-state NMR technique, dipolar recoupling with a windowless sequence (DRAWS), to directly probe the conformation of an acidic peptide adsorbed to hydroxyapatite (HAP) crystals. The phosphorylated hexapeptide, DpSpSEEK (N6, where pS denotes phosphorylated serine), was derived from the N terminus of the salivary protein statherin, Constant-composition kinetic characterization demonstrated that, like the native statherin, this peptide inhibits the growth of HAP seed crystals when preadsorbed to the crystal surface. The DRAWS technique was used to measure the internuclear distance between two C-13 labels at the carbonyl positions of the adjacent phosphoserine residues. Dipolar dephasing measured at short mixing times yielded a mean separation distance of 3.2 +/- 0.1 Angstrom. Data obtained by using longer mixing times suggest a broad distribution of conformations about this average distance. Using a more complex model with discrete cy-helical and extended conformations did not yield a better fit to the data and was not consistent with chemical shift analysis, These results suggest that the peptide is predominantly in an extended conformation rather than an Lu-helical state on the HAP surface, Solid-state NMR approaches can thus be used to determine directly the conformation of biologically relevant peptides on HAP surfaces. A better understanding of peptide and protein conformation on biomineral surfaces may provide design principles useful for the modification of orthopedic and dental implants with coatings and biological growth factors that are designed to enhance biocompatibility with surrounding tissue. C1 Univ Washington, Dept Bioengn, Seattle, WA 98195 USA. Univ Washington, Dept Chem, Seattle, WA 98195 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Stayton, PS (reprint author), Univ Washington, Dept Bioengn, Box 357962, Seattle, WA 98195 USA. FU NIDCR NIH HHS [DE 12554-01, R01 DE012554] NR 36 TC 77 Z9 78 U1 2 U2 24 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 OCT 13 PY 1998 VL 95 IS 21 BP 12083 EP 12087 DI 10.1073/pnas.95.21.12083 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 129DL UT WOS:000076447900005 PM 9770443 ER PT J AU Maziasz, PJ Payzant, EA Schlienger, ME McHugh, KM AF Maziasz, PJ Payzant, EA Schlienger, ME McHugh, KM TI Residual stresses and microstructure of H13 steel formed by combining two different direct fabrication methods SO SCRIPTA MATERIALIA LA English DT Article C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Idaho Natl Engn & Evironm Lab, Idaho Falls, ID 83415 USA. RP Maziasz, PJ (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Payzant, Edward/B-5449-2009; OI Payzant, Edward/0000-0002-3447-2060; Maziasz, Philip/0000-0001-8207-334X NR 5 TC 17 Z9 17 U1 1 U2 6 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 OCT 13 PY 1998 VL 39 IS 10 BP 1471 EP 1476 DI 10.1016/S1359-6462(98)00349-2 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 134PL UT WOS:000076751700022 ER PT J AU Maltez, RL Liliental-Weber, Z Washburn, J Behar, M Klein, PB Specht, P Weber, ER AF Maltez, RL Liliental-Weber, Z Washburn, J Behar, M Klein, PB Specht, P Weber, ER TI Transmission electron microscopy and photoluminescence studies of Er implanted low-temperature grown GaAs : Be SO APPLIED PHYSICS LETTERS LA English DT Article ID ERBIUM-DOPED GAAS AB Characteristic 1.54 mu m 4f-4f emission has been observed from Er3+ centers in Er-implanted and annealed, low-temperature grown GaAs: Be samples, while cross-sectional transmission electron microscopy (TEM) studies reveal very little structural damage for elevated temperature implants. No Er emission was observed from any of the as-implanted samples, while the Er emission intensity was significantly more intense after 650 degrees C anneals than after 750 degrees C anneals. Significant enhancement of the optically active Er incorporation was achieved when the implantation was carried out at 300 degrees C. For the two total Er fluences employed (5.5x10(13) and 13.6x10(13) Er/cm(2)) the Er emission intensity exhibited a linear dependence upon implantation fluence, while TEM indicated no significant increase in the damage level at the higher fluence 300 degrees C implant. (C) 1998 American Institute of Physics. [S0003-6951(98)04641-5]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. UFRGS, Inst Fis, BR-91501970 Porto Alegre, RS, Brazil. USN, Res Lab, Washington, DC 20375 USA. Univ Calif Berkeley, Dept Mat Sci, Berkeley, CA 94720 USA. RP Maltez, RL (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012; Maltez, Rogerio/K-1173-2016 OI Maltez, Rogerio/0000-0002-8653-6118 NR 13 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 12 PY 1998 VL 73 IS 15 BP 2170 EP 2172 DI 10.1063/1.122412 PG 3 WC Physics, Applied SC Physics GA 128UX UT WOS:000076427700035 ER PT J AU Kittel, A Kouznetsov, KA McDermott, R Oh, B Clarke, J AF Kittel, A Kouznetsov, KA McDermott, R Oh, B Clarke, J TI High T-c superconducting second-order gradiometer SO APPLIED PHYSICS LETTERS LA English DT Article ID SQUID; SYSTEM AB A planar, second-order gradiometer was fabricated from single-layer YBa2Cu3O7-x films. The gradiometer consists of a symmetric flux transformer with an overall length of 80 mm inductively coupled to a directly coupled magnetometer, and has a baseline of 31 mm. The mutual inductance between the flux transformer and the magnetometer is adjusted mechanically to reduce the response to a uniform magnetic field applied perpendicularly to the plane of the gradiometer to typically 50 ppm. From an independent measurement, the residual first-order gradient response was determined to be at most 1.4% relative to the second-order gradient response. (C) 1998 American Institute of Physics. [S0003-6951(98)03641-9]. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Clarke, J (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 14 TC 24 Z9 24 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 12 PY 1998 VL 73 IS 15 BP 2197 EP 2199 DI 10.1063/1.122421 PG 3 WC Physics, Applied SC Physics GA 128UX UT WOS:000076427700044 ER PT J AU Freeland, JW Bussmann, K Lubitz, P Idzerda, YU Cao, CC AF Freeland, JW Bussmann, K Lubitz, P Idzerda, YU Cao, CC TI Probing interfacial and bulk magnetic hysteresis in roughened CoFe thin films SO APPLIED PHYSICS LETTERS LA English DT Article ID X-RAY; 2ND-HARMONIC GENERATION; SCATTERING; MULTILAYERS; DICHROISM; IRON AB The hysteretic behavior of interfacial magnetic moments for CoFe thin films with varying roughness is determined in an element specific manner by monitoring the applied magnetic field dependence of the specular and off-specular (diffuse) contributions to the x-ray resonant magnetic scattering signal. Increasing the interfacial roughness generates a larger variation of the relative coercive field associated with the interfacial moment in comparison to the bulk. (C) 1998 American Institute of Physics. [S0003-6951(98)00941-3]. C1 USN, Res Lab, Washington, DC 20375 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. Brookhaven Natl Lab, Naval Res Lab, Upton, NY 11973 USA. RP Freeland, JW (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM freeland@bnlls3.nsls.bnl.gov NR 24 TC 27 Z9 28 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 12 PY 1998 VL 73 IS 15 BP 2206 EP 2208 DI 10.1063/1.122424 PG 3 WC Physics, Applied SC Physics GA 128UX UT WOS:000076427700047 ER PT J AU le Grand, JB Mears, CA Hiller, LJ Frank, M Labov, SE Netel, H Chow, D Friedrich, S Lindeman, MA Barfknecht, AT AF le Grand, JB Mears, CA Hiller, LJ Frank, M Labov, SE Netel, H Chow, D Friedrich, S Lindeman, MA Barfknecht, AT TI A superconducting tunnel junction x-ray detector with performance limited by statistical effects (vol 73, pg 1295, 1998) SO APPLIED PHYSICS LETTERS LA English DT Correction C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Conductus Inc, Sunnyvale, CA 94086 USA. RP le Grand, JB (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-418, Livermore, CA 94550 USA. RI Frank, Matthias/O-9055-2014 NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 12 PY 1998 VL 73 IS 15 BP 2220 EP 2220 DI 10.1063/1.122434 PG 1 WC Physics, Applied SC Physics GA 128UX UT WOS:000076427700057 ER PT J AU Myers, WD Swiatecki, WJ AF Myers, WD Swiatecki, WJ TI A model of nuclear rotation SO NUCLEAR PHYSICS A LA English DT Article AB We construct a model which describes approximately ground-state, superdeformed and fission-isomeric rotational bands of even-even nuclei. The model is based on a three-term energy expression corresponding to: (a) a rigid rotation of part of the nucleus, (b) the energy of initially counter-rotating gyroscopes that the overall rotation gradually aligns in the direction of the total angular momentum, and (c) a potential energy resisting such alignment. The model can be used for a macroscopic description of the angular momentum dependence of nuclear fission barriers. (C) 1998 Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 19 TC 3 Z9 3 U1 0 U2 3 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 OCT 12 PY 1998 VL 641 IS 2 BP 203 EP 225 DI 10.1016/S0375-9474(98)00463-1 PG 23 WC Physics, Nuclear SC Physics GA 132UB UT WOS:000076647500003 ER PT J AU Bern, Z Dixon, L Dunbar, DC Perelstein, M Rozowsky, JS AF Bern, Z Dixon, L Dunbar, DC Perelstein, M Rozowsky, JS TI On the relationship between Yang-Mills theory and gravity and its implication for ultraviolet divergences SO NUCLEAR PHYSICS B LA English DT Review DE unitarity; cutting; ultraviolet divergences; supersymmetry; supergravity; two-loops; multi-loops ID 4-POINT LADDER DIAGRAMS; BACKGROUND FIELD METHOD; MULTI-GLUON SCATTERING; ONE-LOOP DIVERGENCES; STRING-BASED METHODS; GAUGE-THEORIES; HELICITY AMPLITUDES; DIMENSIONAL REGULARIZATION; COLLINEAR LIMITS; 3-POINT DIAGRAMS AB String theory implies that field theories containing gravity are in a certain sense 'products' of gauge theories. We make this product structure explicit up to two loops for the relatively simple case of N = 8 supergravity four-point amplitudes, demonstrating that they are 'squares' of N = 4 super-Yang-Mills amplitudes. This is accomplished by obtaining an explicit expression for the D-dimensional two-loop contribution to the four-particle S-matrix for N = 8 supergravity, which we compare to the corresponding N = 4 Yang-Mills result. From these expressions we also obtain the two-loop ultraviolet divergences in dimensions D = 7 through D = 11. The analysis relies on the unitarity cuts of the two theories, many of which can be recycled from a one-loop computation. The two-particle cuts, which may be iterated to all loop orders, suggest that squaring relations between the two theories exist at any loop order. The loop-momentum power-counting implied by our two-particle cut analysis indicates that in four dimensions the first four-point divergence in N = 8 supergravity should appear at five loops, contrary to the earlier expectation, based on superspace arguments, of a three-loop counterterm. (C) 1998 Elsevier Science B.V. C1 Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Coll Swansea, Dept Phys, Swansea SA2 8PP, W Glam, Wales. RP Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. OI dunbar, david/0000-0003-2433-1675 NR 103 TC 258 Z9 259 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD OCT 12 PY 1998 VL 530 IS 1-2 BP 401 EP 456 DI 10.1016/S0550-3213(98)00420-9 PG 56 WC Physics, Particles & Fields SC Physics GA 133AX UT WOS:000076665200014 ER PT J AU Lopez, RE Dodelson, S Scherrer, RJ Turner, MS AF Lopez, RE Dodelson, S Scherrer, RJ Turner, MS TI Probing unstable massive neutrinos with current cosmic microwave background observations SO PHYSICAL REVIEW LETTERS LA English DT Article ID DARK-MATTER; INFLATION; ANISOTROPIES; CONSTRAINTS; PARTICLES AB The pattern of anisotropies in the cosmic microwave background depends upon the masses and lifetimes of the three neutrino species. A neutrino species of mass greater than 10 eV with lifetime between 10(13) and 10(17) sec leaves a very distinct signature (due to the integrated Sachs-Wolfe effect): the anisotropies at large angles are predicted to be comparable to those on degree scales. Present data exclude such a possibility and hence this region of parameter space. For m(v) similar or equal to 30 eV, tau similar or equal to 10(13) sec, we find an interesting possibility: the integrated Sachs-Wolfe peak produced by the decaying neutrino in low-Omega models mimics the acoustic peak expected in an Omega = 1 model. [S0031-9007(98)07347-5]. C1 Univ Chicago, Dept Phys, Chicago, IL 60637 USA. NASA, Fermi Natl Accelerator Lab, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Univ Chicago, Dept Astron & Astrophys, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Lopez, RE (reprint author), Univ Chicago, Dept Phys, Chicago, IL 60637 USA. NR 34 TC 23 Z9 23 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3075 EP 3078 DI 10.1103/PhysRevLett.81.3075 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400007 ER PT J AU Antunes, ND Bettencourt, LMA AF Antunes, ND Bettencourt, LMA TI The length distribution of vortex strings in U(1) equilibrium scalar field theory SO PHYSICAL REVIEW LETTERS LA English DT Article ID STATISTICAL-MECHANICS; COSMIC STRINGS AB We characterize the statistical length distribution of vortex strings by studying the nonperturbative thermodynamics of scalar U(1) field theory in 3D. All parameters characterizing the length distributions exhibit critical behavior at T-c and we measure their associated critical exponents. Moreover, we show that vortex strings are generally self-seeking at finite temperature and that there exists a natural separation between long strings and small loops based on their spatial correlation behavior. [S0031-9007(98)07128-2]. C1 Univ Sussex, Ctr Theoret Phys, Brighton BN1 9QJ, E Sussex, England. Univ Calif Los Alamos Natl Lab, Theoret Div T6T11 MSB288, Los Alamos, NM 87545 USA. RP Antunes, ND (reprint author), Univ Sussex, Ctr Theoret Phys, Brighton BN1 9QJ, E Sussex, England. NR 14 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 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3083 EP 3086 DI 10.1103/PhysRevLett.81.3083 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400009 ER PT J AU Bernard, C Blum, T DeTar, C Gottlieb, S Heller, UM Hetrick, JE McNeile, C Rummukainen, K Sugar, R Toussaint, D AF Bernard, C Blum, T DeTar, C Gottlieb, S Heller, UM Hetrick, JE McNeile, C Rummukainen, K Sugar, R Toussaint, D TI Continuum limit of lattice QCD with staggered quarks in the quenched approximation: A critical role for the chiral extrapolation SO PHYSICAL REVIEW LETTERS LA English DT Article ID PERTURBATION-THEORY; HADRON MASSES; FERMIONS AB We calculate the light quark spectrum of lattice QCD in the quenched approximation using staggered quarks. We take the light quark mass, infinite volume, continuum limit. With nonlinear chiral extrapolations, we find that the nucleon to rho mass ratio is m(N)/m(rho) = 1.254 +/- 0.018 +/- 0.028, where the errors are statistical and systematic (within the quenched approximation), respectively. Since the experimental value is 1.22, our results indicate that the error due to quenching is less than or equal to 5%. [S0031-9007(98)07361-X]. C1 Washington Univ, St Louis, MO 63130 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Utah, Salt Lake City, UT 84112 USA. Indiana Univ, Bloomington, IN 47405 USA. Florida State Univ, Supercomp Computat Res Inst, Tallahassee, FL 32306 USA. Univ Pacific, Stockton, CA 95211 USA. NORDITA, DK-2100 Copenhagen O, Denmark. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Arizona, Tucson, AZ 85721 USA. RP Washington Univ, St Louis, MO 63130 USA. OI Hetrick, James/0000-0002-0740-2251; Heller, Urs M./0000-0002-2780-5584; DeTar, Carleton/0000-0002-0216-6771; Rummukainen, Kari/0000-0003-2266-4716 NR 22 TC 19 Z9 19 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3087 EP 3090 DI 10.1103/PhysRevLett.81.3087 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400010 ER PT J AU Bai, JZ Bian, JG Blum, I Chai, ZW Chen, GP Chen, HF Chen, J Chen, JC Chen, Y Chen, YB Chen, YQ Cheng, BS Cui, XZ Ding, HL Ding, LY Dong, LY Du, ZZ Dunwoodie, W Feng, S Gao, CS Cao, ML Gao, SQ Gratton, P Gu, JH Gu, SD Gu, WX Gu, YF Guo, YN Han, SW Han, Y Harris, FA He, J He, JT He, M Hitlin, DG Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Hu, XQ Huang, JD Huang, YZ Izen, JM Jiang, CH Jin, Y Ke, ZJ Kelsey, MH Kim, BK Kong, D Lai, YF Lang, PF Lankford, A Li, CG Li, D Li, HB Li, J Li, PQ Li, RB Li, W Li, WD Li, WG Li, XH Li, XN Liu, HM Liu, J Liu, JH Liu, RG Liu, Y Lou, XC Lowery, B Lu, F Lu, JG Lu, JY Lu, LC Luo, CH Ma, AM Ma, EC Ma, JM Malchow, R Mao, HS Mao, ZP Meng, XC Nie, J Olsen, SL Oyang, J Paluselli, D Pan, LJ Panetta, J 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, XY Sheng, HY Shi, HZ Song, XF Standifird, J Sun, F Sun, HS Tang, SQ Toki, W Tong, GL Varner, G Wang, F Wang, LS Wang, LZ Wang, M Wang, M Wang, P Wang, PL Wang, SM Wang, TJ Wang, YY Weaver, M Wei, CL Wu, YG Xi, DM Xia, XM Xie, PP Xie, Y Xie, YH Xiong, WJ Xu, CC Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, J Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yi, K Yu, CS Yu, CX Yu, YH Yu, ZQ Yu, ZT Yuan, CZ Yuan, Y Zhang, BY Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JL Zhang, JW Zhang, LS Zhang, QJ Zhang, SQ Zhang, XY Zhang, Y Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, M Zhao, WR Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhou, GP Zhou, HS Zhou, L Zhu, QM Zhu, YC Zhu, YS Zhuang, BA AF Bai, JZ Bian, JG Blum, I Chai, ZW Chen, GP Chen, HF Chen, J Chen, JC Chen, Y Chen, YB Chen, YQ Cheng, BS Cui, XZ Ding, HL Ding, LY Dong, LY Du, ZZ Dunwoodie, W Feng, S Gao, CS Cao, ML Gao, SQ Gratton, P Gu, JH Gu, SD Gu, WX Gu, YF Guo, YN Han, SW Han, Y Harris, FA He, J He, JT He, M Hitlin, DG Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Hu, XQ Huang, JD Huang, YZ Izen, JM Jiang, CH Jin, Y Ke, ZJ Kelsey, MH Kim, BK Kong, D Lai, YF Lang, PF Lankford, A Li, CG Li, D Li, HB Li, J Li, PQ Li, RB Li, W Li, WD Li, WG Li, XH Li, XN Liu, HM Liu, J Liu, JH Liu, RG Liu, Y Lou, XC Lowery, B Lu, F Lu, JG Lu, JY Lu, LC Luo, CH Ma, AM Ma, EC Ma, JM Malchow, R Mao, HS Mao, ZP Meng, XC Nie, J Olsen, SL Oyang, J Paluselli, D Pan, LJ Panetta, J 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, XY Sheng, HY Shi, HZ Song, XF Standifird, J Sun, F Sun, HS Tang, SQ Toki, W Tong, GL Varner, G Wang, F Wang, LS Wang, LZ Wang, M Wang, M Wang, P Wang, PL Wang, SM Wang, TJ Wang, YY Weaver, M Wei, CL Wu, YG Xi, DM Xia, XM Xie, PP Xie, Y Xie, YH Xiong, WJ Xu, CC Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, J Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yi, K Yu, CS Yu, CX Yu, YH Yu, ZQ Yu, ZT Yuan, CZ Yuan, Y Zhang, BY Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JL Zhang, JW Zhang, LS Zhang, QJ Zhang, SQ Zhang, XY Zhang, Y Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, M Zhao, WR Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhou, GP Zhou, HS Zhou, L Zhu, QM Zhu, YC Zhu, YS Zhuang, BA TI Study of the P-wave charmonium state chi(cJ) in psi/(2S) decays SO PHYSICAL REVIEW LETTERS LA English DT Article ID QCD; ANNIHILATION AB The processes psi(2S) --> gamma pi(+)pi(-), gamma K+K-, and gamma p (p) over bar have been studied using a sample of 3.79 x 10(6) psi(2S) decays. We determine the total width of the chi(c0) to be Gamma(chi c0)(tot) = 14.3 +/- 2.0 +/- 3.0 MeV. We present the first measurement of the branching fraction B(chi(c0) --> p (p) over bar) = (15.9 1 4.3 i 5.3) x 10(-5) where the first error is statistical and the second one is systematic. Branching fractions of chi(c0,2) --> pi(+)pi(-) and K+K- are also reported. [S0031-9007(98)07355-4]. C1 Inst High Energy Phys, Beijing 100039, Peoples R China. CALTECH, Pasadena, CA 91125 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Hangzhou Univ, Hangzhou 310028, Peoples R China. Shandong Univ, Jinan 250100, Peoples R China. Shanghai Jiao Tong Univ, Shanghai 200030, Peoples R China. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Calif Irvine, Irvine, CA 92717 USA. Univ Sci & Technol China, Hefei 230026, Peoples R China. Univ Texas, Richardson, TX 75083 USA. CCAST, World Lab, Beijing 100080, Peoples R China. RP Bai, JZ (reprint author), Inst High Energy Phys, Beijing 100039, Peoples R China. RI Chen, Yu/E-3788-2012; OI Li, Xiaonan/0000-0003-2857-0219 NR 13 TC 37 Z9 39 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3091 EP 3095 DI 10.1103/PhysRevLett.81.3091 PG 5 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400011 ER PT J AU Jansons, KM Lythe, GD AF Jansons, KM Lythe, GD TI Stochastic Stokes drift SO PHYSICAL REVIEW LETTERS LA English DT Article ID DRIVEN RATCHETS; TRANSPORT; DIFFUSION; MOTION; WAVES AB Classical Stokes drift is the small time-averaged drift velocity of suspended nondiffusing particles in a fluid due to the presence of a wave. We consider the effect of adding diffusion to the motion of the particles and show in particular that a nonzero time-averaged drift velocity exists in general even when the classical Stokes drift is zero. Our results are obtained from a general procedure for calculating ensemble-averaged Lagrangian mean velocities for motion that is close to Brownian and are verified by numerical simulations in the case of sinusoidal forcing. [S0031-9007(98)07364-5]. C1 Univ London Univ Coll, Dept Math, London WC1E 6BT, England. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Jansons, KM (reprint author), Univ London Univ Coll, Dept Math, Gower St, London WC1E 6BT, England. OI Lythe, Grant/0000-0001-7966-5571 NR 15 TC 25 Z9 25 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 OCT 12 PY 1998 VL 81 IS 15 BP 3136 EP 3139 DI 10.1103/PhysRevLett.81.3136 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400022 ER PT J AU Chu, TK AF Chu, TK TI Turbulent steady-state configuration of an inductively driven reversed field pinch plasma SO PHYSICAL REVIEW LETTERS LA English DT Article ID TOROIDAL PLASMA AB An inductively driven reversed field pinch plasma has a time-averaged steady-state magnetic configuration. The configuration, which is force-free, corresponds to a state of minimum rate of dissipation of magnetic energy for a prescribed rate of dissipation of magnetic helicity. The ratio of the two dissipation rates equals the ratio of the sustaining Poynting flux to magnetic helicity flux at the boundary. The turbulence arises because it is not possible to maintain a stationary Poynting flux. [S0031-9007(98)07356-6]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Chu, TK (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 12 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3148 EP 3150 DI 10.1103/PhysRevLett.81.3148 PG 3 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400025 ER PT J AU Conrad, EH Menzel, A Kiriukhin, S Tringides, MC AF Conrad, EH Menzel, A Kiriukhin, S Tringides, MC TI Observations of surface temporal fluctuations by low energy electron diffraction SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIFFUSION AB We present evidence for equilibrium temporal fluctuations in a high resolution low energy electron diffraction (LEED) experiment. These fluctuations are the reciprocal space analog of current fluctuations in field emission microscopy and therefore can be used to extract surface kinetic information. We show that even when the electron beam illuminates an area larger than its correlation length, time correlated data can be extracted from LEED. To demonstrate this, we present time dependent data from a W(430) surface, which reflects thermal step fluctuations. Our results illustrate the potential of LEED as a real time, ultrafast probe. [S0031-9007(95)07297-4]. C1 Georgia Inst Technol, Sch Phys, Atlanta, GA 30032 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Conrad, EH (reprint author), Georgia Inst Technol, Sch Phys, Atlanta, GA 30032 USA. RI Menzel, Andreas/C-4388-2012 OI Menzel, Andreas/0000-0002-0489-609X NR 15 TC 10 Z9 10 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 OCT 12 PY 1998 VL 81 IS 15 BP 3175 EP 3178 DI 10.1103/PhysRevLett.81.3175 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400032 ER PT J AU Price, DL Saboungi, ML Barnes, AC AF Price, DL Saboungi, ML Barnes, AC TI Structure of vitreous germania SO PHYSICAL REVIEW LETTERS LA English DT Article ID INTERMEDIATE-RANGE; MOLECULAR-DYNAMICS; ORDER; LIQUID; MOLTEN; SIO2 AB A full partial structure factor analysis of vitreous germania has been obtained by a combination of neutron diffraction, x-ray diffraction, and anomalous x-ray scattering. The results are consistent with the identification of the first three peaks in the average neutron and x-ray structure factors with intermediate-range order, chemical short-range order, and topological short-range order, respectively. The values for the shortest distances for the three element pairs are in agreement with previous work and suggest that possible complications with this technique, which might arise for example from shifts of the centers of the electron distributions from the nuclei, are not serious in the case of oxide glasses. [S0031-9007(98)07248-2]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. RP Price, DL (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Price, David Long/A-8468-2013; Saboungi, Marie-Louise/C-5920-2013 OI Saboungi, Marie-Louise/0000-0002-0607-4815 NR 20 TC 71 Z9 71 U1 0 U2 5 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 OCT 12 PY 1998 VL 81 IS 15 BP 3207 EP 3210 DI 10.1103/PhysRevLett.81.3207 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400040 ER PT J AU Back, CH Weller, D Heidmann, J Mauri, D Guarisco, D Garwin, EL Siegmann, HC AF Back, CH Weller, D Heidmann, J Mauri, D Guarisco, D Garwin, EL Siegmann, HC TI Magnetization reversal in ultrashort magnetic field pulses SO PHYSICAL REVIEW LETTERS LA English DT Article AB Strong in-plane magnetic field pulses of 2-4.4 ps duration are used to study magnetization reversal in perpendicularly magnetized Co/Pt films. Ring domains, reminiscent of the field contour during exposure, are observed later with Kerr microscopy. Their radii represent switching fields which are in quantitative agreement with the coherent rotation model. The observation of intrinsic transition broadening is attributed to the existence of static and dynamic fluctuations of the magnetic anisotropy. [S0031-9007(98)07344-X]. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. IBM Corp, Storage Syst Div, San Jose, CA 95193 USA. Stanford Univ, Dept Mat Sci Engn, Stanford, CA 94305 USA. ETH Zurich, Festkorperphys Lab, Zurich, Switzerland. RP Back, CH (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RI Back, Christian/A-8969-2012 OI Back, Christian/0000-0003-3840-0993 NR 15 TC 129 Z9 130 U1 1 U2 13 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3251 EP 3254 DI 10.1103/PhysRevLett.81.3251 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400051 ER PT J AU Wang, HL Hou, HQ Hammons, BE AF Wang, HL Hou, HQ Hammons, BE TI Coherent dynamics of excitonic nonlinear optical response in the nonperturbative regime SO PHYSICAL REVIEW LETTERS LA English DT Article ID SEMICONDUCTOR QUANTUM MICROCAVITY; CAVITY POLARITONS; OSCILLATIONS AB We report experimental and theoretical studies of the transient nonlinear response from semiconductor microcavities. We show that, in the nonperturbative regime, oscillations in time-integrated transient four-wave mixing do not correspond to normal mode oscillations of either the exciton or photon population in the cavity. Coherent nonlinear responses arising from band filling, excitation-induced dephasing, and renormalized electric fields feature highly distinctive dynamical behaviors. Coherent dynamics in transient four-wave mixing reflects interference between these nonlinear processes. dynamics in transient four-wave mixing reflects [S0031-9007(98)07305-0]. C1 Univ Oregon, Dept Phys, Eugene, OR 97403 USA. Univ Oregon, Oregon Ctr Opt, Eugene, OR 97403 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wang, HL (reprint author), Univ Oregon, Dept Phys, Eugene, OR 97403 USA. RI Wang, Hailin/A-2362-2011 NR 14 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 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3255 EP 3258 DI 10.1103/PhysRevLett.81.3255 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400052 ER PT J AU Lizzit, S Pohl, K Baraldi, A Comelli, G Fritzsche, V Plummer, EW Stumpf, R Hofmann, P AF Lizzit, S Pohl, K Baraldi, A Comelli, G Fritzsche, V Plummer, EW Stumpf, R Hofmann, P TI Physics of the Be(10(1)over-bar0) surface core level spectrum SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHOTOELECTRON DIFFRACTION; BE(0001) SURFACE; SHIFTS AB Photoelectron diffraction has been utilized to confirm the theoretical prediction that the surface core level shifts observed for Be(<10(1)over bar 0>) have been improperly assigned. The original assignment based upon the relative intensity of the shifted components was intuitively obvious: the peak with the largest shift of -0.7 eV with respect to the bulk was associated with the surface plane, the next peak shifted by -0.5 eV stems from the second layer, and the third peak at -0.22 eV from the third and fourth layers. First-principles theory and our experimental data show that the largest shift is associated with the second plane, not the first plane. [S0031-9007(98)07350-5]. C1 Univ Aarhus, Inst Storage Ring Facil, Aarhus, Denmark. Max Planck Gesell, Fritz Haber Inst, D-1000 Berlin, Germany. Univ Tennessee, Dept Phys & Astron, Oak Ridge, TN 37831 USA. Sincrotrone Trieste, I-34012 Trieste, Italy. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Trieste, Sincrotrone Trieste, INFM, Lab TASC, Trieste, Italy. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hofmann, P (reprint author), Univ Aarhus, Inst Storage Ring Facil, Aarhus, Denmark. RI Hofmann, Philip/B-5938-2008 OI Hofmann, Philip/0000-0002-7367-5821 NR 13 TC 27 Z9 27 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 12 PY 1998 VL 81 IS 15 BP 3271 EP 3274 DI 10.1103/PhysRevLett.81.3271 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400056 ER PT J AU Buttler, WT Hughes, RJ Kwiat, PG Lamoreaux, SK Luther, GG Morgan, GL Nordholt, JE Peterson, CG Simmons, CM AF Buttler, WT Hughes, RJ Kwiat, PG Lamoreaux, SK Luther, GG Morgan, GL Nordholt, JE Peterson, CG Simmons, CM TI Practical free-space quantum key distribution over 1 km SO PHYSICAL REVIEW LETTERS LA English DT Article ID OPTICAL-FIBER; CRYPTOGRAPHY; LONG AB A working free-space quantum key distribution system has been developed and tested over an outdoor optical path of similar to 1 km at Los Alamos National Laboratory under nighttime conditions. Results show that free-space quantum key distribution can provide secure real-time key distribution between parties who have a need to communicate secretly. Finally, we examine the feasibility of surface to satellite quantum key distribution. [S0031-9007(98)07299-8]. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 23 TC 153 Z9 166 U1 2 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 OCT 12 PY 1998 VL 81 IS 15 BP 3283 EP 3286 DI 10.1103/PhysRevLett.81.3283 PG 4 WC Physics, Multidisciplinary SC Physics GA 127UR UT WOS:000076369400059 ER PT J AU Chiu, SW Cheung, YS Ma, NL Li, WK Ng, CY AF Chiu, SW Cheung, YS Ma, NL Li, WK Ng, CY TI A G2 ab initio study of C2H5S+ ions: I. Structures, energetics, and unimolecular isomerizations of non-carbenoid isomers SO THEOCHEM-JOURNAL OF MOLECULAR STRUCTURE LA English DT Article DE Gaussian-2 theory; [C2H5S+] ions; [C2H5O+] ions; potential energy surfaces; unimolecular rearrangements; unimolecular dissociations ID POTENTIAL-ENERGY SURFACE; NEUTRAL COMPLEXES; TRANSITION-STATE; GAS-PHASE; PHOTOIONIZATION; CATIONS; CHEMISTRY; ABINITIO; RADICALS; THERMOCHEMISTRY AB The potential energy surface of [C2H5S+] ions was studied with the G2 method. The structures and G2 heats of formation (Delta H-f0) of CH3CH2S+ (1(+)), syn-CH3CHSH+ (2(+)), anti-CH3CHSH+ (3(+)), and CH3SCH2+ (4(+)) were reported previously (1993, Chem. Phys. Lett., 213, 250). The G2 Delta H-f298 = 802 kJ mol(-1) of c-CH2CH2SH+ (7(+)) is in good agreement with the experimental Delta H-f298 (7(+)) = 798 kT mol(-1) (1988, J. Phys. Chem. Ref. Data, Suppl. 1). The symmetric conformer of protonated vinyl thiol CH2CHSH2+ (Delta H-f0 (9(+)) = 857 W mol(-1)) is slightly more stable than the non-symmetric one (8(+)) by 8 kJ mol(-1). The C-C protonated thiirane 11(+) with Delta H-f0 = 989 W mol(-1) is an intermediate for the 1,3-H shift 4(+) --> 4(+). The isomerization reactions 8(+)/9(+) --> 2(+)/3(+) --> 7(+) --> 4(+) are energetically facile compared to the unimolecular dissociation processes. The Delta H-f0 of the transition state structures for these isomerizations lies within a narrow range of 960-1000 kJ mol(-1). The calculated energetics of [C2H5S+] are in line with the observation (1979, Org. Mass Spectrom. 14, 543) that both 2(+)/3(+) and 4(+) isomerize to a common structure 7+ and decompose through the same reaction channels. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Illinois, Natl Ctr Supercomp Applicat, Beckman Inst 4043, Urbana, IL 61801 USA. Univ Illinois, Dept Mol & Integrat Physiol, Beckman Inst 4043, Urbana, IL 61801 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Hong Kong Polytech Univ, Dept Appl Biol & Chem Technol, Hong Kong, Hong Kong. Chinese Univ Hong Kong, Dept Chem, Shatin, NT, Hong Kong. US DOE, Ames Lab, Ames, IA 50011 USA. RP Chiu, SW (reprint author), Univ Illinois, Natl Ctr Supercomp Applicat, Beckman Inst 4043, MC-251,405 N Mathew Ave, Urbana, IL 61801 USA. NR 56 TC 15 Z9 15 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 THEOCHEM-J MOL STRUC JI Theochem-J. Mol. Struct. PD OCT 12 PY 1998 VL 452 BP 97 EP 115 DI 10.1016/S0166-1280(98)00135-3 PG 19 WC Chemistry, Physical SC Chemistry GA 129DV UT WOS:000076448800009 ER PT J AU Bellwied, R Beuttenmuller, R Chen, W DiMassimo, D Dou, L Dyke, H French, A Hall, JR Hoffmann, GW Humanic, T Kotov, IV Kraner, HW Li, Z Lynn, D Ott, G Pandey, SU Pruneau, C Rykov, VL Schambach, J Sedlmeir, J Sugarbaker, E Takahashi, J Wilson, WK AF Bellwied, R Beuttenmuller, R Chen, W DiMassimo, D Dou, L Dyke, H French, A Hall, JR Hoffmann, GW Humanic, T Kotov, IV Kraner, HW Li, Z Lynn, D Ott, G Pandey, SU Pruneau, C Rykov, VL Schambach, J Sedlmeir, J Sugarbaker, E Takahashi, J Wilson, WK CA STAR-SVT collaboration TI Electron injection in semiconductor drift detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID STAR EXPERIMENT; SILICON AB We report on the injection of electrons from surface structures of Silicon Drift Detectors into the bulk of the detector for calibration purposes. Also, with these injector structures, detection of magnetic field components perpendicular to the detector's surface is possible. Implanted line and dot injectors along with MOS injectors are discussed. Studies of lateral uniformity of injection, biasing of injectors to facilitate injection and dot injection are discussed. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Wayne State Univ, Dept Phys & Astron, Detroit, MI 48202 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Texas, Austin, TX 78712 USA. IHEP, Protvino, Russia. Univ Sao Paulo, Sao Paulo, Brazil. RP Bellwied, R (reprint author), Wayne State Univ, Dept Phys & Astron, Phys Res Bldg, Detroit, MI 48202 USA. RI Takahashi, Jun/B-2946-2012 OI Takahashi, Jun/0000-0002-4091-1779 NR 7 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 11 PY 1998 VL 416 IS 1 BP 70 EP 80 DI 10.1016/S0168-9002(98)00561-0 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 132TZ UT WOS:000076647300009 ER PT J AU Halpern, MB Schwartz, C AF Halpern, MB Schwartz, C TI Asymptotic search for ground states of SU(2) matrix theory SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article ID QUANTUM-MECHANICS; BOUND-STATES; SUPERSYMMETRY; BRANES AB We introduce a complete set of gauge-invariant variables and a generalized Born-Oppenheimer formulation to search for normalizable zero-energy asymptotic solutions of the Schrodinger equation of SU(2) matrix theory. The asymptotic method gives only ground state candidates, which must be further tested for global stability. Our results include a set of such ground state candidates, including one state which is a singlet under spin (9). C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Halpern, MB (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM halpern@physics.berkeley.edu NR 20 TC 47 Z9 47 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD OCT 10 PY 1998 VL 13 IS 25 BP 4367 EP 4408 DI 10.1142/S0217751X98002110 PG 42 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 125KF UT WOS:000076236200005 ER PT J AU VanderHeyden, WB Kashiwa, BA AF VanderHeyden, WB Kashiwa, BA TI Compatible fluxes for van Leer advection SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE finite-difference approximations; synchronous advection; computational fluid dynamics; gradient limiting AB Application of the standard second-order upstream-centered advection method of van Leer to a coupled transport equation system of the form (delta/delta t)[(rho)(A)] + del.[(rho)(A)]u = 0 can produce artificial extrema in the ratio T = A/rho, even though T satisfies a simple advection equation and is expected to preserve monotonicity. Here u is velocity, rho is mass density, and A is a conserved quantity such as momentum density, energy density, or chemical species density. Thus T is a mass;specific transport quantity such as velocity, energy per unit mass, temperature, or species mass fraction. A new Aux formulation and gradient limiting procedure is presented here which eliminates these artificial extrema, preserves the second-order accuracy, and preserves the monotone character of the van Leer method, even in the limit of vanishing mass density. Such a formulation is called compatible. The method is noniterative (i.e. explicit) and can be employed in a general finite-volume framework. Sample results for the transport of a square wave in one and two dimensions are provided. (C) 1998 Academic Press. C1 Los Alamos Natl Lab, Theoret Div Fluid Dynam Grp, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Theoret Div Fluid Dynam Grp, Mail Stop B216, Los Alamos, NM 87545 USA. EM wbv@lanl.gov; bak@lanl.gov NR 10 TC 13 Z9 13 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 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD OCT 10 PY 1998 VL 146 IS 1 BP 1 EP 28 DI 10.1006/jcph.1998.6070 PG 28 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 129DN UT WOS:000076448100001 ER PT J AU Caramana, EJ Burton, DE Shashkov, MJ Whalen, PP AF Caramana, EJ Burton, DE Shashkov, MJ Whalen, PP TI The construction of compatible hydrodynamics algorithms utilizing conservation of total energy SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article AB The principal goal of all numerical algorithms is to represent as faithfully and accurately as possible the underlying continuum equations to which a numerical solution is sought. However, in the transformation of the equations of fluid dynamics into discretized form important physical properties an either lost, or obeyed only to an approximation that often becomes worse with time, This is because the numerical methods used to form the discrete analog of these equations may only represent them to some order of local truncation error without explicit regard to global properties of the continuum system. Although a finite truncation error is inherent to all discretization methods, it is possible to satisfy certain global properties, such as conservation of mass, momentum, and total energy, to numerical roundoff error. The purpose of this work is to show how these equations can be differenced compatibly so that they obey the aforementioned properties. In particular, it is shown how conservation of total energy can be utilized as an intermediate device to achieve this goal for the equations of fluid dynamics written in Lagrangian form, and with a staggered spatial placement of variables for any number of dimensions and in any coordinate system. For staggered spatial variables it is shown how the momentum equation and the specific internal energy equation can be derived from each other in a simple and generic manner by use of the conservation of total energy, This allows for the specification of forces that can be of an arbitrary complexity, such as those derived from an artificial viscosity or subzonal pressures. These forces originate only in discrete form; nonetheless, the change in internal energy caused by them is still completely determined. The procedure given here is compared to the "method of support operators," to which it is closely related. Difficulties with conservation of momentum, volume, and entropy are also discussed. The proper treatment of boundary conditions and differencing with respect to time are detailed. (C) 1998 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Hydrodynam Methods Grp, Math Modelling & Anal Grp, Appl Theoret & Computat Phys Div,Theoret Div, Los Alamos, NM 87545 USA. RP Caramana, EJ (reprint author), Univ Calif Los Alamos Natl Lab, Hydrodynam Methods Grp, Math Modelling & Anal Grp, Appl Theoret & Computat Phys Div,Theoret Div, POB 1663,MS D413, Los Alamos, NM 87545 USA. NR 25 TC 202 Z9 224 U1 0 U2 14 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 OCT 10 PY 1998 VL 146 IS 1 BP 227 EP 262 DI 10.1006/jcph.1998.6029 PG 36 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 129DN UT WOS:000076448100010 ER PT J AU He, X Chen, S Doolen, GD AF He, X Chen, S Doolen, GD TI A novel thermal model for the lattice Boltzmann method in incompressible limit SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID RAYLEIGH-BENARD CONVECTION; SIMULATIONS; FLOW; HYDRODYNAMICS; EQUATION; FLUIDS AB A novel lattice Boltzmann thermal model is proposed for studying thermohydrodynamics in incompressible limit. The new model introduces an internal energy density distribution function to simulate the temperature field. The macroscopic density and velocity fields are still simulated using the density distribution function. Compared with the multispeed thermal lattice Boltzmann models, the current scheme is numerically more stable. In addition, the new model can incorporate viscous heat dissipation and compression work done by the pressure, in contrast to the passive-scalar-based thermal lattice Boltzmann models. Numerical simulations of Couette flow with a temperature gradient and Rayleigh-Benard convection agree well with analytical solutions and benchmark data. (C) 1998 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP He, X (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Chen, Shiyi/A-3234-2010 NR 32 TC 678 Z9 711 U1 12 U2 106 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 OCT 10 PY 1998 VL 146 IS 1 BP 282 EP 300 DI 10.1006/jcph.1998.6057 PG 19 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 129DN UT WOS:000076448100012 ER PT J AU Adams, ML Nowak, PF AF Adams, ML Nowak, PF TI Asymptotic analysis of a computational method for time- and frequency-dependent radiative transfer SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE radiative transfer; asymptotic analysis; computational transport; spatial discretization AB We consider a time-dependent, energy-dependent, nonlinear radiative transfer problem in which opacities are large [O(epsilon(-1))] and interior sources are small [O(epsilon)]. An asymptotic analysis of this problem as epsilon --> 0 leads to the equilibrium diffusion equation in the interior of the system, along with boundary conditions and initial conditions for this equation. We apply the same asymptotic analysis to a discrete version of the problem, in which the frequency variable is discretized by the multigroup method, the direction variable by the discrete-ordinates method, the time variable by the fully implicit method, and the spatial variable by a subcell-balance method. We find that as epsilon --> 0 the discrete solution satisfies a robust discretized version of the comet equilibrium diffusion equation, with boundary conditions and initial conditions that are remarkably accurate. The analysis thus predicts that if a spatial grid is chosen that resolves interior temperature gradients, then the numerical method obtains an accurate solution in the interior of the system, even though the optical thickness of the spatial cells tends to infinity and boundary layers in the transport solution are not resolved. We go a step further to analyze problems that are optically thin at some photon frequencies but thick at others, and show that once again the discrete solution is remarkably accurate. We present numerical results that verify these and other predictions of the analyses. (C) 1998 Academic Press. C1 Texas A&M Univ, Dept Nucl Engn, College Stn, TX 77843 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Adams, ML (reprint author), Texas A&M Univ, Dept Nucl Engn, College Stn, TX 77843 USA. NR 14 TC 22 Z9 23 U1 0 U2 1 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 OCT 10 PY 1998 VL 146 IS 1 BP 366 EP 403 DI 10.1006/jcph.1998.6063 PG 38 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 129DN UT WOS:000076448100016 ER PT J AU Steck, LK Thurber, CH Fehler, MC Lutter, WJ Roberts, PM Baldridge, WS Stafford, DG Sessions, R AF Steck, LK Thurber, CH Fehler, MC Lutter, WJ Roberts, PM Baldridge, WS Stafford, DG Sessions, R TI Crust and upper mantle P wave velocity structure beneath Valles caldera, New Mexico: Results from the Jemez teleseismic tomography experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID RIO-GRANDE RIFT; VOLCANIC FIELD; SIMULTANEOUS INVERSION; TOLEDO CALDERA; HEAT-FLOW; EVOLUTION; CALIFORNIA; MOUNTAINS; ANOMALIES; RHYOLITES AB New results are presented from the teleseismic component of the Jemez Tomography Experiment conducted across Valles caldera in northern New Mexico. We invert 4872 relative P wave arrival times recorded on 50 portable stations to determine velocity structure to depths of 40 km. The three principle features of our model for Valles caldera are: (1) near-surface low velocities of -17% beneath the Toledo embayment and the Valle Grande, (2) midcrustal low velocities of -23% in an ellipsoidal volume underneath the northwest quadrant of the caldera, and (3) a broad zone of low velocities (-15%) in the lower crust or upper mantle. Crust shallower than 20 km is generally fast to the northwest of the caldera and slow to the southeast. Near-surface low velocities are interpreted as thick deposits of Bandelier tuff and postcaldera volcaniclastic rocks. Lateral variation in the thickness of these deposits supports increased caldera collapse to the southeast, beneath the Valle Grande. We interpret the midcrustal low-velocity zone to contain a minimum melt fraction of 10%. While we cannot rule out the possibility that this zone is the remnant 1.2 Ma Bandelier magma chamber, the eruption history and geochemistry of the volcanic rocks erupted in Valles caldera following the Bandelier tuff make it more likely that magma results from a new pulse of intrusion, indicating that melt flux into the upper crust beneath Valles caldera continues. The low-velocity zone near the crust-mantle boundary is consistent with either partial melt in the lower crust or mafic rocks without partial melt in the upper mantle. In either case, this low-velocity anomaly indicates that underplating by mantle-derived melts has occurred. C1 Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. Univ Wisconsin, Dept Geol & Geophys, Madison, WI 53706 USA. RP Steck, LK (reprint author), Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, POB 1663, Los Alamos, NM 87545 USA. EM lsteck@lanl.gov; clifft@geology.wisc.edu; fehler@lanl.gov; wlutter@geology.wisc.edu; roberts@seismo5.lanl.gov; sbaldridge@lanl.gov; dstafford@lanl.gov NR 51 TC 46 Z9 46 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD OCT 10 PY 1998 VL 103 IS B10 BP 24301 EP 24320 DI 10.1029/98JB00750 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 127WK UT WOS:000076373400034 ER PT J AU Milanovic, L Bosch, HA Hoover, WG AF Milanovic, L Bosch, HA Hoover, WG TI "What is liquid'? Understanding the states of matter SO MOLECULAR PHYSICS LA English DT Article ID LYAPUNOV INSTABILITY; MOLECULAR-DYNAMICS; PHASE-TRANSITION; CURVATURE; EXPONENT; SPECTRA; FLUIDS AB Molecular dynamics answers the question "what is 'liquid'?" by describing the detailed dynamic structure of simulated liquids in the many-dimensional phase space of statistical mechanics. The Lyapunov instabilities of liquid motion reveal collective dynamic modes, quite unlike those of solid state studies, superimposed on the van der Waals hard particle static structure. Here we illustrate these developments in the characterization of 'liquid' with examples from our recent dynamic instability studies of two-dimensional dumbbell fluids. C1 Univ Vienna, Inst Expt Phys, A-1090 Vienna, Austria. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Milanovic, L (reprint author), Univ Vienna, Inst Expt Phys, Boltzmanngasse 5, A-1090 Vienna, Austria. NR 24 TC 27 Z9 27 U1 0 U2 5 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD OCT 10 PY 1998 VL 95 IS 2 BP 281 EP 287 DI 10.1080/002689798167205 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 130PG UT WOS:000076528000021 ER PT J AU Ree, FH Kim, JH AF Ree, FH Kim, JH TI A statistical mechanical study on the melting lines of He-3 and He-4 SO MOLECULAR PHYSICS LA English DT Article ID HIGH-PRESSURE PHASE; HARD-SPHERE FLUID; X-RAY-DIFFRACTION; PERTURBATION-THEORY; SOLID HE-4; THERMODYNAMIC PROPERTIES; REPULSIVE FORCES; ISOTOPIC SHIFT; SIMPLE LIQUIDS; STATE AB A theoretical melting line is sensitive to a small difference in solid and fluid free energies. Such a difference may arise from different approximations made in fluid and solid theories and also from inaccuracies in handling anharmonic lattice vibrations. Statistical mechanical calculations have been made for liquid and solid He-4 and He-3 and their melting lines, using a new perturbation theory (PT) which does not suffer from the above limitations. These calculations, which use the Aziz potential for helium, are augmented by additional calculations using quasiharmonic lattice dynamics and Mansoori-Canfield-Ross theory (with an exponential-6 potential). Comparisons of these results and available Monte Carlo and real experimental data show that the PT can accurately predict solid, fluid, and the melting data of a model of helium (based on the Aziz potential) and that the melting line of real 4He is insensitive to many-body effects up to 200 K, but their influence grows gradually with pressure (approximate to 6% in melting pressure at 300 K). An effective pair potential is suggested which can handle many-body contributions over an extended density range. The calculations on the isotopic pressure shift, Delta P-m = P-m(He-3) - P-m(He-4), along the melting lines of helium isotopes show that Delta P-m > 0 at T < 100 K in agreement with experiment at T approximate to 30 K and Delta P-m < 0 at T > 100 K in agreement with path integral Monte Carlo data. The PT with the first-order quantum correction was found to explain the experimental melting data surprisingly well; i.e., beyond an estimated range of applicability of the Wigner-Kirkwood expansion. It can imply a rapid convergence of the Wigner-Kirkwood expansion along the melting line of He-4. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Kongju Natl Univ, Dept Chem Educ, Kong Ju 314701, Chungnam, South Korea. RP Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 41 TC 1 Z9 1 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0026-8976 EI 1362-3028 J9 MOL PHYS JI Mol. Phys. PD OCT 10 PY 1998 VL 95 IS 2 BP 331 EP 339 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 130PG UT WOS:000076528000026 ER PT J AU Beilis, II Keidar, M Boxman, RL Goldsmith, S AF Beilis, II Keidar, M Boxman, RL Goldsmith, S TI Effects of macroparticle separation in positively biased ducts in the filtered vacuum arc deposition systems SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 25th International Conference on Metallurgical Coatings and Thin Films CY APR 25-MAY 01, 1998 CL SAN DIEGO, CALIFORNIA SP Vacuum Met, Thin Film Div, AVS DE filtered vacuum arc; positive bias; macroparticles ID CATHODIC-ARC; PLASMA; TRANSPORT; COATINGS; FILMS; GENERATION; GROWTH; TIN AB The objective of the present work was to calculate the influence of positive bias on macroparticle (MP) how in a curved magnetized plasma duct. A non-stationary model for MP charging and motion in the duct wall sheath was developed. Two cases of MP charging were considered: for large MPs (radii greater than or equal to 1 mu m) and small MPs (<1 mu m). MP trapping in the sheath was found in both cases. MPs may move in the sheath region along the wall by a repetitive process of electrostatic attraction to the wall, mechanical reflection and neutralization, followed by MP charging and attraction, etc. The effective sticking coefficient of the MP to the wall increases due to an increasing number of MP collisions with the wall when MP is trapped in the near wall sheath. Using experimental MP size distributions for Ti, Cu and C cathodes it was obtained that the MP transmission fraction through the filter decreases due to the trapping effect when a bias potential of +80 V is applied between the wall and the plasma. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Tel Aviv Univ, Elect Discharge & Plasma Lab, IL-69978 Tel Aviv, Israel. RP Keidar, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS-53, Berkeley, CA 94720 USA. NR 26 TC 7 Z9 7 U1 1 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD OCT 10 PY 1998 VL 108 IS 1-3 BP 148 EP 153 DI 10.1016/S0257-8972(98)00657-4 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 142LY UT WOS:000077203000023 ER PT J AU Wood, BP Perry, AJ Bitteker, LJ Waganaar, WJ AF Wood, BP Perry, AJ Bitteker, LJ Waganaar, WJ TI Cratering behavior in single- and poly-crystalline copper irradiated by an intense pulsed ion beam SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 25th International Conference on Metallurgical Coatings and Thin Films CY APR 25-MAY 01, 1998 CL SAN DIEGO, CALIFORNIA SP Vacuum Met, Thin Film Div, AVS DE intense pulsed ion beam; ion diode; cratering ID SURFACE AB When treated with intense pulsed ion beams (IPIB), many materials exhibit increased wear resistance, fatigue life, and hardness. However, this treatment often results in cratering and roughening of the surface. In this work, high purity single crystal and polycrystalline copper samples were irradiated with pulses from an IPIB to determine whether this cratering is due to (1) bulk alloy content, (2) impact of anode debris, or (3) grain structure. Samples were treated with 1, 2, 5, and 10 shots at an average energy fluence per shot of 2 and 5 J/cm(2). Shots were about 400 ns in duration and consisted of a mixture of carbon, hydrogen, and oxygen ions at 300 keV. It was found that the single crystal copper cratered far less than the polycrystalline copper at the lower energy fluence. At the higher energy fluence, cratering was replaced by other forms of surface damage, and the single crystal copper sustained less damage at all but the largest number of shots. Molten debris from the Lucite anode (the ion source) was removed and redeposited on the samples with each shot. From this, we conclude that neither bulk alloy content nor anode debris impact cause cratering. Grain structure affects cratering, although the mechanism for this is not determined in this study. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Plasma Phys Grp, Los Alamos, NM 87545 USA. AIMS Mkt, San Diego, CA 92127 USA. RP Wood, BP (reprint author), Univ Calif Los Alamos Natl Lab, Plasma Phys Grp, MS-E526, Los Alamos, NM 87545 USA. NR 13 TC 38 Z9 42 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD OCT 10 PY 1998 VL 108 IS 1-3 BP 171 EP 176 DI 10.1016/S0257-8972(98)00659-8 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 142LY UT WOS:000077203000027 ER PT J AU Allendorf, MD Melius, CF AF Allendorf, MD Melius, CF TI Understanding gas-phase reactions in the thermal CVD of hard coatings using computational methods SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 25th International Conference on Metallurgical Coatings and Thin Films CY APR 25-MAY 01, 1998 CL SAN DIEGO, CA SP Vacuum Met, Thin Film Div, AVS DE chemical vapor deposition; computational methods; ab initio techniques; bond additivity correction (BAC) method; RRKM theory; gas-phase kinetics; TiCl4; decomposition; boron nitride; silicon carbide ID CHEMICAL-VAPOR-DEPOSITION; H SYSTEM; CHEMISTRY; THERMOCHEMISTRY; MOLECULES; DECOMPOSITION; MODEL; METHYLTRICHLOROSILANE; PREDICTIONS; ADDITIVITY AB This article provides a short summary of the theoretical approaches to understanding gas-phase reactions. In particular, the quantum-chemical bond-additivity correction (BAC) method for predicting molecular thermochemistry of gas-phase molecules is described. A brief discussion of the use of RRKM methods for predicting the rates of unimolecular reactions and of ab initio methods for predicting the rates of bimolecular reactions is also presented. Finally, the question of when gas-phase reactions are likely to be important in CVD is discussed. Criteria are proposed for performing a first-order evaluation of the extent of precursor pyrolysis in the CVD of hard coatings. Examples from the CVD of titanium-containing species, boron nitride, and silicon carbide will be used for illustration. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Sandia Natl Labs, Livermore, CA 94551 USA. EM mdallen@sandia.gov NR 47 TC 21 Z9 21 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD OCT 10 PY 1998 VL 108 IS 1-3 BP 191 EP 199 DI 10.1016/S0257-8972(98)00660-4 PG 9 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 142LY UT WOS:000077203000030 ER PT J AU Delplancke-Ogletree, MP Monteiro, OR AF Delplancke-Ogletree, MP Monteiro, OR TI Wear behavior of diamond-like carbon metal carbide multilayers SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 25th International Conference on Metallurgical Coatings and Thin Films CY APR 25-MAY 01, 1998 CL SAN DIEGO, CALIFORNIA SP Vacuum Met, Thin Film Div, AVS DE vacuum arc; multilayers; DLC; metal carbide; wear; multilayer coating; friction ID CATHODIC-ARC DEPOSITION; PLASMA IMMERSION; COATINGS; FILMS; MICROSTRUCTURE AB The high level of stress in hard diamond-like carbon (DLC) films limits their maximum thickness and their compliance with substrate deformation. Multilayer films are one approach to overcome these disadvantages. We have prepared multilayers of DLC/TiCx and DLC/WCx by filtered cathodic vacuum are, then investigated and compared their wear properties at room temperature. The films were deposited on polished, oil-hardened AISI 01 tool steel substrates. The number and thickness of layers within the films were varied while the total thickness was approximately constant. Friction coefficients and wear were measured as a function of the atmosphere and load in ball-on-disk tests. Tests were performed in dry nitrogen and in air with relative humidity of 50%. Initial Hertzian contact pressures of 0.8 and 1.4 GPa were used with alumina balls. For all films showing good wear resistance, both the layer in immediate contact with the steel and the topmost layer were DLC. The failure mechanism and the wear resistance were found to be highly dependent on the type of carbide, on the atmosphere during the wear test and on the thickness and number of individual layers. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Delplancke-Ogletree, MP (reprint author), Free Univ Brussels, B-1050 Brussels, Belgium. EM mpdelpla@ulb.ac.be NR 16 TC 55 Z9 56 U1 3 U2 11 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD OCT 10 PY 1998 VL 108 IS 1-3 BP 484 EP 488 DI 10.1016/S0257-8972(98)00572-6 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 142LY UT WOS:000077203000078 ER PT J AU Liu, C Huang, Y Stout, MG AF Liu, C Huang, Y Stout, MG TI Enhanced mode-II fracture toughness of an epoxy resin due to shear banding SO ACTA MATERIALIA LA English DT Article ID BRAZILIAN DISK TEST; BEHAVIOR AB The Brazilian disk specimen is used to measure the fracture toughness of an epoxy resin material under mode-I and mode-II loading conditions. It is found that even though the apparent fracture behavior seems to be brittle for both loading modes, the mode-II fracture toughness is more than three times higher than the mode-I fracture toughness. Such a substantial increase in fracture toughness under mode-II loading contradicts the prediction of the maximum hoop stress criterion, which has been validated for most brittle fractures. Results of unidirectional tension and compression tests of the epoxy resin indicate that under the mode-II loading, shear banding can develop ahead of the crack tip before the brittle fracture occurs. The substantial increase of the mode-II fracture toughness can be accounted for by including the contributions of the shear banding. A mechanical model was developed to study the effects of the shear band on the mode-II fracture toughness. This model suggests that the extension direction of a mode-II crack is still controlled by the orientation of the maximum hoop stress; however, the critical energy-release rate should include contributions from both the maximum hoop stress and the shear band. The effect of different stress distribution profiles inside the shear band is studied with the model as well. (C) 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. Ali rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MST 8, Los Alamos, NM 87545 USA. Univ Illinois, Dept Mech & Ind Engn, Urbana, IL 61801 USA. RP Liu, C (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MST 8, Los Alamos, NM 87545 USA. RI Huang, Yonggang/B-6998-2009 NR 17 TC 16 Z9 22 U1 0 U2 7 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 OCT 9 PY 1998 VL 46 IS 16 BP 5647 EP 5661 DI 10.1016/S1359-6454(98)00253-5 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 137TB UT WOS:000076931300004 ER PT J AU Yoshimi, K Yoo, MH Hanada, S AF Yoshimi, K Yoo, MH Hanada, S TI Slip band propagation and slip vector transition in B2 FeAl single crystals SO ACTA MATERIALIA LA English DT Article ID HIGH-TEMPERATURES; AL; FRACTURE; FLOW; INSTABILITIES; COMPRESSION; BEHAVIOR; TENSILE; STRESS AB At the peak temperature, 823 K, of the yield strength anomaly of B2 FeAl, slip band propagation and slip vector transition were investigated using Fe-39 mol% Al single crystals. The single crystal oriented along a compression axis close to the [<(1)over bar 23>] direction showed serrated flow during work-hardening at small strains (<2%). Coarse slip bands propagate in the single crystal specimens, like Luders band propagation in polycrystals, in the initial strain range. The slip vector was identified by TEM to be parallel to [111] in the early stage of strain corresponding to yielding. Beyond plastic strains of about 3%, serrations disappeared and significant work-softening occurred. The slip vector responsible for the later stage of deformation was observed to be [100]. That is, the slip vector changes from [111] to [100] as the plastic strain increases. Because the density of [111] superdislocations is found to be very low after the slip transition, glide decomposition of [111] superdislocations is believed to the primary source mechanism for [100] dislocations. The slip band propagation in B2 single crystals is discussed in comparison with that of other intermetallic single-crystalline materials. (C) 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Tohoku Univ, Inst Mat Res, Sendai, Miyagi 98077, Japan. RP Yoshimi, K (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 24 TC 14 Z9 14 U1 5 U2 14 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 OCT 9 PY 1998 VL 46 IS 16 BP 5769 EP 5776 DI 10.1016/S1359-6454(98)00228-6 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 137TB UT WOS:000076931300013 ER PT J AU Chen, X Mariappan, SVS Kelley, JJ Bushweller, JH Bradbury, EM Gupta, G AF Chen, X Mariappan, SVS Kelley, JJ Bushweller, JH Bradbury, EM Gupta, G TI A PCR-based method for uniform C-13/N-15 labeling of long DNA oligomers SO FEBS LETTERS LA English DT Article DE uniform labeling of DNA duplexes; polymerase chain reaction; multi-nuclear magnetic resonance; high resolution structure ID NMR-SPECTROSCOPY; DODECAMER; PROTEINS; SPECTRA AB A polymerase chain reaction (PCR)-based method is described for uniform C-13/N-15 labeling of DNA duplexes, In this method, multiple copies of a blunt-ended duplex are cloned into a plasmid with each copy containing the sequence of interest and the restriction HincII sequences at the 5' and 3' ends. PCR with uniformly C-13/N-15-labeled dNTP precursors results in a labeled DNA duplex containing multiple copies of the sequence of interest, Use of bi-directional primers, instead of self-priming [Louis et al, (1998) J, Biol. Chem, 273, 2374-2378], produces a DNA fragment of unique length. Twenty-four; cycles of PCR of this purified product followed by restriction and purification gives (with 30% yield) the uniformly C-13/N-15-labeled duplex sequence for multi-nuclear magnetic resonance! spectroscopy. (C) 1998 Federation of European Biochemical Societies. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. Dartmouth Coll, Dept Chem, Hanover, NH 03755 USA. Univ Calif Davis, Sch Med, Dept Biol Chem, Davis, CA 95616 USA. RP Gupta, G (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-10,MS K710, Los Alamos, NM 87545 USA. NR 17 TC 12 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0014-5793 J9 FEBS LETT JI FEBS Lett. PD OCT 9 PY 1998 VL 436 IS 3 BP 372 EP 376 DI 10.1016/S0014-5793(98)01162-4 PG 5 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 130VE UT WOS:000076540400016 PM 9801151 ER PT J AU Dombrowski, SM Krishnan, R Witte, M Maitra, S Diesing, C Waters, LC Ganguly, R AF Dombrowski, SM Krishnan, R Witte, M Maitra, S Diesing, C Waters, LC Ganguly, R TI Constitutive and barbital-induced expression of the Cyp6a2 allele of a high producer strain of CYP6A2 in the genetic background of a low producer strain SO GENE LA English DT Article DE cytochrome P450 monooxygenase; DNA sequencing; germ line transformation; RNA blot analysis; insecticide resistance; gene expression ID MESSENGER-RNA DEGRADATION; LONG TERMINAL REPEAT; HOUSE-FLY MICROSOMES; DROSOPHILA-MELANOGASTER; INSECTICIDE RESISTANCE; MUSCA-DOMESTICA; BROAD-COMPLEX; PHENOBARBITAL INDUCTION; BACILLUS-MEGATERIUM; SUSCEPTIBLE STRAINS AB The levels of one or more cytochrome P450 (CYP) enzymes and the respective mRNAs are found to be higher in insecticide-resistant insects than in susceptible insects. To understand better how insects regulate the levels of CYPs, we examined the expression of the Cyp6a2 gene in various strains of Drosophila melanogaster. We also took a transgenic approach to understand the molecular mechanisms that are involved in strain variation of Cyp6a2 expression. RNA blot analysis showed that the constitutive expression of Cyp6a2 varies from strain to strain; the level of CYP6A2 mRNA is barely detectable in the underproducer ry(506) strain, whereas it is very high in the overproducer 91-R and MHIII-D23 strains. The long terminal repeat (LTR) of mobile element 17.6 that is found in the 3' untranslated region (UTR) of the Cyp6a2 gene of some strains does not appear to have any role on the steady-state CYP6A2 mRNA level. We also found that the Cyp6a2 gene is inducible by barbital in 91-R, y(506) as well as 91-C, which carries an LTR insertion. To examine the genetic background of the underproducer ry506 Strain with respect to Cyp6a2 expression, we transformed the ry(506) Strain with the Cyp6a2 allele of the overproducer 91-R strain (Cyp6a2-91R) and measured the constitutive and barbital-induced expression of the Cyp6a2-91R transgene in the transformed flies. The Cyp6a2-91R transgene carrying 129 bp of DNA upstream of the ATG codon did not show any constitutive or barbital-induced expression in the ry(506) host genome. However, transgenes with 1331 and 985 bp upstream DNA showed similar levels of constitutive expression that were higher than that of the endogenous Cyp6a2 gene of the ry(506) host strain, but lower than the expression of the same gene in the 91-R strain. Both these transgenes, with 1331 and 985 bp upstream DNA, also showed induction with 0.1 M barbital. DNA sequence analysis revealed that in both 91-R and ry(506), the upstream DNA between +1 and -985 bp contains a distal and a proximal group of three potential barbie boxes, i.e. cis-elements that are thought to be involved in barbiturate-mediated induction of CYP genes. Except for four bases located near the distal cluster of barbie boxes and two other bases, the base sequence of the upstream DNA is identical in ry(506) and 91-R strains. These results suggest that the underproducer ry(506) Strain has the trans-regulatory factors to support constitutive and induced expression of the Cyp6a2-91R allele carrying DNA between -129 and -1331 bp regions. Possible reasons for low constitutive expression of the endogenous Cyp6a2 gene and moderate level of expression of the Cyp6a2-91R allele in the ry(506) genetic background are discussed. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Biochem & Cellular & Mol Biol, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Ganguly, R (reprint author), Univ Tennessee, Dept Biochem & Cellular & Mol Biol, Knoxville, TN 37996 USA. EM rganguly@utk.edu NR 40 TC 39 Z9 40 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1119 J9 GENE JI Gene PD OCT 9 PY 1998 VL 221 IS 1 BP 69 EP 77 DI 10.1016/S0378-1119(98)00436-3 PG 9 WC Genetics & Heredity SC Genetics & Heredity GA 139KE UT WOS:000077027200009 PM 9852951 ER PT J AU An, WJ van Holde, K Zlatanova, J AF An, WJ van Holde, K Zlatanova, J TI The non-histone chromatin protein HMG1 protects linker DNA on the side opposite to that protected by linker histones SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID 4-WAY JUNCTION DNA; CHROMOSOMAL-PROTEINS; H1; TRANSCRIPTION; COMPETITION; NUCLEOSOMES; BINDING; B4 AB Linker histones and HMG1/2 constitute the two major proteins that bind to linker DNA in chromatin. While the location of linker histones on the nucleosome has attracted considerable research effort, only a few studies have addressed the location of HMG1 in the particles. In this study, we use a procedure based on micrococcal nuclease digestion of reconstituted nucleosomal particles to which HMG1 has been bound, followed by analysis of the protected DNA by restriction nuclease digestion, to locate the HMG1 binding site. Nucleosomal particles were reconstituted on a 235-base pair DNA fragment, which is known to be a strong nucleosome positioning sequence. The results unequivocally show that HMG1 protects linker DNA on one side of the core particle. Importantly, and possibly of physiological relevance, the linker DNA site protected by HMG1 was located on the side opposite to that already shown to be protected by linker histone binding. C1 Oregon State Univ, Dept Biochem & Biophys, Corvallis, OR 97331 USA. Bulgarian Acad Sci, Inst Genet, BU-1113 Sofia, Bulgaria. RP Zlatanova, J (reprint author), Argonne Natl Lab, Bldg 202-A253,9700 S Cass Ave, Argonne, IL 60439 USA. EM zlatanoj@everest.bim.anl.gov RI Zlatanova, Jordanka/B-3273-2009 FU FIC NIH HHS [TW00568]; NIGMS NIH HHS [GM50276] NR 19 TC 29 Z9 29 U1 0 U2 0 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD OCT 9 PY 1998 VL 273 IS 41 BP 26289 EP 26291 DI 10.1074/jbc.273.41.26289 PG 3 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 127WJ UT WOS:000076373300009 PM 9756855 ER PT J AU McAteer, K Jing, Y Kao, J Taylor, JS Kennedy, MA AF McAteer, K Jing, Y Kao, J Taylor, JS Kennedy, MA TI Solution-state structure of a DNA dodecamer duplex containing a cis-syn thymine cyclobutane dimer, the major UV photoproduct of DNA SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE DNA structure; NMR; UV-photoproducts; B-II backbone ID MOLECULAR-DYNAMICS STRUCTURE; NMR COUPLING-CONSTANTS; HUMAN CELL-EXTRACTS; TRANS-SYN; ESCHERICHIA-COLI; OLIGODEOXYRIBONUCLEOTIDE DUPLEX; OLIGONUCLEOTIDE DUPLEX; CONFORMATIONAL-CHANGES; CRYSTAL-STRUCTURE; CYANOETHYL ESTER AB The solution structures of a duplex DNA dodecamer containing a cis-syn cyclobutane thymine dimer d(GCACGAAT[cs]TAAG).d(CTTAATTCG-TGC) and its native parent sequence were determined using NMR data collected at 750 MHz. The dodecamer sequence corresponds to the section of a site-specific cis-syn dimer containing 49-mer that was found to be the binding site for the dimer-specific T4 denV endonuclease V repair enzyme by chemical and enzymatic footprinting experiments. Structures of both sequences were derived from NOE restrained molecular dynamics/simulated annealing calculations using a fixed outer layer of water and an inner dynamic layer of water with sodium counterions. The resulting structures reveal a subtle distortion to the phosphodiester backbone in the dimer-containing sequence which includes a B-II phosphate at the T9pA10 junction immediately 3' to the dimer. The B-II phosphate, established experimentally by analysis of the P-31 chemical shifts and interpretation of the (3)J(P-H3') values using an optimized Karplus relationship, enables the DNA helix to accommodate the dimer by destacking the base 3' to the dimer. Furthermore, the structures provide explanations for the unusually shifted T8-N3H imino, A16-H2 and T8-Me proton resonances and T9pA10 P-31 NMR resonance and are consistent with bending, unwinding, and thermodynamic data. The implications of the structural data for the mechanism by which cis-syn dimers are recognized by repair enzymes and bypassed by DNA polymerases are also discussed. (C) 1998 Academic Press. C1 Pacific NW Natl Lab, Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. RP Kennedy, MA (reprint author), Pacific NW Natl Lab, Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. EM ma_kennedy@pnl.gov FU NCI NIH HHS [R37 CA40463]; NCRR NIH HHS [RR-02004, RR-05018] NR 69 TC 90 Z9 90 U1 3 U2 13 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD OCT 9 PY 1998 VL 282 IS 5 BP 1013 EP 1032 DI 10.1006/jmbi.1998.2062 PG 20 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 128MV UT WOS:000076411300008 PM 9753551 ER PT J AU Merritt, EA Kuhn, P Sarfaty, S Erbe, JL Holmes, RK Ho, WGJ AF Merritt, EA Kuhn, P Sarfaty, S Erbe, JL Holmes, RK Ho, WGJ TI The 1.25 angstrom resolution refinement of the cholera toxin B-pentamer: Evidence of peptide backbone strain at the receptor-binding site SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE anisotropic displacement parameters; atomic resolution; complex oligosaccharide; crystal structure; SHELXL ID HEAT-LABILE ENTEROTOXIN; ESCHERICHIA-COLI; CRYSTAL-STRUCTURES; ATOMIC-RESOLUTION; 1.0 ANGSTROM; ERRORS; BOND; LT AB Crystals of the 61 kDa complex of the cholera toxin B-pentamer with the ganglioside G(M1) receptor pentasaccharide diffract to near-atomic resolution. We have refined the crystallographic model for this complex using anisotropic displacement parameters for all atoms to a conventional crystallographic residual R = 0.129 for all observed Bragg reflections in the resolution range 22 Angstrom to 1.25 Angstrom. Remarkably few residues show evidence of discrete conformational disorder. A notable exception is a minority conformation found for the Cys9 side-chain, which implies that the Cys9-Cys86 disulfide linkage is incompletely formed, in all five crystallographically independent instances, the peptide backbone in the region of the receptor-binding site shows evidence of strain, including unusual bond lengths and angles, and a highly non-planar to = 153.7(7)degrees) peptide group between residues Gln49 and Val50. The location of well-ordered water molecules at the protein surface is notable reproduced among the five crystallographically independent copies of the peptide chain, both at the receptor-binding site and elsewhere. The 5-fold noncrystallographic symmetry of this complex allows an evaluation of the accuracy, reproducibility, and derived error estimates from refinement of large structures at near-atomic resolution. We find that blocked-matrix treatment of parameter covariance underestimates the uncertainty of atomic positions in the final model by approximately 10% relative to estimates based either on full-matrix inversion or on the 5-fold non-crystallographic symmetry. (C) 1998 Academic Press. C1 Univ Washington, Biomol Struct Ctr, Dept Biol Struct, Seattle, WA 98195 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Univ Washington, Howard Hughes Med Inst, Seattle, WA 98195 USA. Univ Colorado, Sch Med, Dept Microbiol, Denver, CO 80262 USA. RP Merritt, EA (reprint author), Univ Washington, Biomol Struct Ctr, Dept Biol Struct, Seattle, WA 98195 USA. EM merritt@u.washington.edu FU NIAID NIH HHS [AI31940, AI34501] NR 41 TC 119 Z9 121 U1 0 U2 11 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD OCT 9 PY 1998 VL 282 IS 5 BP 1043 EP 1059 DI 10.1006/jmbi.1998.2076 PG 17 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 128MV UT WOS:000076411300010 PM 9753553 ER PT J AU Ben-Naim, E Krapivsky, PL AF Ben-Naim, E Krapivsky, PL TI Steady-state properties of traffic flows SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article ID PHASE-TRANSITIONS; RANDOM RATES; MODEL; KINETICS AB The role of the passing mechanism in traffic flows is examined. Specifically, we consider passing rates that are proportional to the difference between the velocities of the passing car and the passed car. From a Boltzmann equation approach, steady-state properties of the Bow such as the flux. average cluster size, and velocity distributions are found analytically. We show that a single dimensionless parameter determines the nature of the Bow and helps distinguish between dilute and dense flows. For dilute Bows, perturbation expressions are obtained, while for dense flows a boundary layer analysis is carried out. In the latter case. extremal properties of the initial velocity distribution underly the leading scaling asymptotic behaviour. For dense flows, the stationary velocity distribution exhibits a rich 'triple-deck' boundary layer structure. Furthermore, in this regime fluctuations in the flux may become extremely large. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Boston Univ, Ctr Polymer Studies, Boston, MA 02215 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. RP Ben-Naim, E (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Ben-Naim, Eli/C-7542-2009; Krapivsky, Pavel/A-4612-2014 OI Ben-Naim, Eli/0000-0002-2444-7304; NR 32 TC 10 Z9 10 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD OCT 9 PY 1998 VL 31 IS 40 BP 8073 EP 8080 DI 10.1088/0305-4470/31/40/004 PG 8 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 130GQ UT WOS:000076512200004 ER PT J AU Seaborg, GT AF Seaborg, GT TI Nature Medicine's reply policy SO SCIENCE LA English DT Letter C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Calif Acad Stand Commiss, Sci Comm, Berkeley, CA 94720 USA. RP Seaborg, GT (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Calif Acad Stand Commiss, Sci Comm, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD OCT 9 PY 1998 VL 282 IS 5387 BP 240 EP 241 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 127VA UT WOS:000076370200021 ER PT J AU Lederman, LM Bardeen, MG AF Lederman, LM Bardeen, MG TI Science education reform - Response SO SCIENCE LA English DT Letter C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Lederman, LM (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD OCT 9 PY 1998 VL 282 IS 5387 BP 241 EP 242 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 127VA UT WOS:000076370200023 ER PT J AU Lin, SY Chow, E Hietala, V Villeneuve, PR Joannopoulos, JD AF Lin, SY Chow, E Hietala, V Villeneuve, PR Joannopoulos, JD TI Experimental demonstration of guiding and bending of electromagnetic waves in a photonic crystal SO SCIENCE LA English DT Article ID GUIDES AB The routing and interconnection of optical signals through narrow channels and around sharp corners are important for large-scale all-optical circuit applications. A recent computational result suggests that photonic crystals may offer a novel way of achieving this goal by providing a mechanism for guiding light that is fundamentally different from traditional index guiding. Waveguiding in a photonic crystal and near 100 percent transmission of electromagnetic waves around sharp 90 degree corners were observed experimentally. Bending radii were made smaller than one wavelength. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM slin@sandia.gov NR 14 TC 575 Z9 603 U1 7 U2 46 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 EI 1095-9203 J9 SCIENCE JI Science PD OCT 9 PY 1998 VL 282 IS 5387 BP 274 EP 276 DI 10.1126/science.282.5387.274 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 127VA UT WOS:000076370200041 ER PT J AU Cernota, PD Yoon, HA Salmeron, M Somorjai, GA AF Cernota, PD Yoon, HA Salmeron, M Somorjai, GA TI The structure of para-xylene and meta-xylene adsorbed on Rh(111) studied by scanning tunneling microscopy SO SURFACE SCIENCE LA English DT Article DE chemisorption; rhodium; scanning tunneling microscopy; single crystal surfaces; xylene ID COPPER-PHTHALOCYANINE; MOLECULES; ADSORPTION; SURFACES; BENZENE; IMAGES; STM; GRAPHITE; PD(111); CO AB Scanning tunneling microscopy (STM) was used to study the adsorption of para- and meta-xylene on the Rh(lll) surface. Para-xylene appears in the STM images as a diamond-shaped feature with the long axis oriented along the [11 (2) over bar] and equivalent directions. Ordered domains with three orientations differing by 120 degrees are formed. The images of the meta-isomer have the appearance of triangular shapes and do not form any ordered structure. Individually, however, they are oriented with one side of the triangle parallel to the compact [1 (1) over bar 0] directions. The internal structure in the molecular images can be discerned. By a combination of symmetry and packing considerations, it is possible to attribute the brightest part of the molecular image as due to the methyl groups. When the two isomers are coadsorbed, they exhibit complete mixing, and the individual components can be differentiated by their shape. At low coverage, both xylene molecules adsorb preferentially at the step edges, whereas on the terraces, they are mobile in the time scale of the STM imaging. Coadsorption with CO produces a mixed layer, and the xylene molecules become immobile. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Salmeron, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 19 TC 25 Z9 25 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD OCT 9 PY 1998 VL 415 IS 3 BP 351 EP 362 DI 10.1016/S0039-6028(98)00571-8 PG 12 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 134EQ UT WOS:000076730300026 ER PT J AU Rodriguez, JA Chaturvedi, S Kuhn, M AF Rodriguez, JA Chaturvedi, S Kuhn, M TI A comparison of the reaction of S-2 with metallic copper, Cu2O and Cu/ZnO: electronic properties and reactivity of copper SO SURFACE SCIENCE LA English DT Letter DE ab initio quantum-chemical calculations; copper; copper oxide; photoelectron spectroscopy; sulfur; surface chemical reaction; zinc oxide ID SINGLE-CRYSTAL SURFACES; GAS SHIFT REACTION; OXIDE SURFACES; METHANOL SYNTHESIS; HYDROGEN-SULFIDE; CO CHEMISORPTION; ACTIVE-SITES; ZINC-OXIDE; ADSORPTION; MODEL AB The adsorption of S-2 on polycrystalline copper, Cu2O and Cu/ZnO surfaces has been examined by using synchrotron-based photoemission plus INDO/S and ab initio self-consistent-held calculations. S-2 mainly interacts with the metal centers of Cu/ZnO, Cu2O and ZnO. The chemical affinity of these systems for sulfur increases following the sequence: ZnO < Cu2O < Cu/ZnO < Cu. The copper atoms in the Cu2O and Cu/ZnO systems display band structures that are substantially different from that of metallic copper, and these electronic perturbations affect their reactivity towards S-2. Once copper is bonded to oxygen on ZnO or in Cu2O, its electron density decreases, making more difficult the formation of Cu-->S-2 dative bonds and the breaking of the S-S bond. The poisoning of Cu/ZnO catalysts by sulfur is discussed in the light of these results. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. EM rodrigez@bnl.gov NR 52 TC 13 Z9 13 U1 1 U2 14 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 OCT 9 PY 1998 VL 415 IS 3 BP L1065 EP L1073 DI 10.1016/S0039-6028(98)00626-8 PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 134EQ UT WOS:000076730300012 ER PT J AU Nyman, G Yu, HG Walker, RB AF Nyman, G Yu, HG Walker, RB TI Reduced dimensionality quantum scattering calculations on the Cl+CH4 -> HCl+CH3 reaction SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DIFFERENTIAL-CROSS-SECTIONS; POTENTIAL-ENERGY SURFACE; TRANSITION-STATE THEORY; CH4+OH->CH3+H2O REACTION; REACTION CL+CH4->CH3+HCL; CHEMICAL-REACTIONS; 4-ATOM REACTIONS; KINETICS; METHANE; CL AB Reduced dimensionality quantum scattering calculations using the Rotating Line Approximation, RLA, are performed on the Cl+CH4-->HCl+CH3 reaction, treating CH4 as a pseudo-diatom QH. A LEPS potential energy surface is used, where the zero-point energy of the modes not explicitly treated in the RLA calculations are included. The calculations are performed using hyperspherical coordinates and the improved log-derivative method of Manolopoulos. Boundary conditions have been applied using a hyperspherical projection method and an approximate method where the boundary conditions are applied directly in the hyperspherical coordinates. It is explicitly shown that the agreement between the methods is good. Scattering resonances are observed and related to the shape of the hyperspherical adiabats. Cumulative and state-to-state reaction probabilities are also presented. Vibrational adiabaticity is found to dominate without being exclusive. For Cl+CH4(upsilon =1)-->HCl(n=1)+CH3 and a translational energy of 0.159 eV, measured differential cross sections give predominantly forward scattering, while for Cl+CH4(upsilon = 1)-->HCl(n = 0) + CH3 there is predominantly backward and sideways scattering. Our calculated differential cross sections are in agreement with these general observations. Thermal rate constants have been calculated for the temperature range 200-800 K, The calculated rate constants are smaller than the experimental ones by less than 40% over the entire temperature range. (C) 1998 American Institute of Physics. C1 Gothenburg Univ, Dept Chem, S-41296 Gothenburg, Sweden. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Nyman, G (reprint author), Gothenburg Univ, Dept Chem, S-41296 Gothenburg, Sweden. RI Nyman, Gunnar/B-1705-2009; Yu, Hua-Gen/N-7339-2015 NR 68 TC 50 Z9 50 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 8 PY 1998 VL 109 IS 14 BP 5896 EP 5904 DI 10.1063/1.477212 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 125BE UT WOS:000076216900023 ER PT J AU Hummer, G Pratt, LR Garcia, AE AF Hummer, G Pratt, LR Garcia, AE TI Molecular theories and simulation of ions and polar molecules in water SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID PERIODIC BOUNDARY-CONDITIONS; FREE-ENERGY DIFFERENCES; CONTINUUM ELECTROSTATIC MODEL; EXPLICIT SOLVENT CALCULATION; RANGE COULOMB INTERACTIONS; FINITE-SIZE CORRECTIONS; SOLVATION FREE-ENERGIES; DYNAMICS FREE-ENERGY; COMPUTER-SIMULATIONS; EQUILIBRIUM PROPERTIES AB Recent developments in molecular theories and simulation of ions and polar molecules in water are reviewed. The hydration of imidazole and imidazolium is used to exemplify the theoretical issues. The treatment of long-ranged electrostatic interactions in simulations is discussed extensively. It is argued that the Ewald approach is an easy way to get correct hydration free energies corresponding to thermodynamic limit from molecular calculations. Molecular simulations with Ewald interactions and periodic boundary conditions can also be more efficient than many common alternatives. The Ewald treatment permits a conclusive extrapolation to infinite system size. Accurate results for well-defined models have permitted careful testing of simple theories of electrostatic hydration free energies, such as dielectric continuum models. The picture that emerges from such testing is that the most prominent failings of the simplest theories are associated with solvent proton conformations that lead to non-Gaussian fluctuations of electrostatic potentials. Thus, the most favorable cases for second-order perturbation theories are monoatomic positive ions. For polar and anionic solutes, continuum or Gaussian theories are less accurate. The appreciation of the specific deficiencies of those simple models have led to new concepts, multistate Gaussian and quasi-chemical theories, which address the cases for which the simpler theories fail. It is argued that, relative to direct dielectric continuum treatments, the quasi-chemical theories provide a better theoretical organization for the computational study of the electronic structure of solution species. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Pratt, LR (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Mail Stop B268, Los Alamos, NM 87545 USA. RI Pratt, Lawrence/H-7955-2012; Hummer, Gerhard/A-2546-2013 OI Pratt, Lawrence/0000-0003-2351-7451; Hummer, Gerhard/0000-0001-7768-746X NR 79 TC 152 Z9 151 U1 4 U2 33 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 OCT 8 PY 1998 VL 102 IS 41 BP 7885 EP 7895 DI 10.1021/jp982195r PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 132EF UT WOS:000076616800002 ER PT J AU Mook, HA Dai, PC Hayden, SM Aeppli, G Perring, TG Dogan, F AF Mook, HA Dai, PC Hayden, SM Aeppli, G Perring, TG Dogan, F TI Spin fluctuations in YBa2Cu3O6.6 SO NATURE LA English DT Article ID MAGNETIC FLUCTUATIONS; SUPERCONDUCTING LA2-XSRXCUO4; NEUTRON-SCATTERING; SUSCEPTIBILITY; DYNAMICS AB An important feature of the high-transition-temperature (high-T-c) copper oxide superconductors is the magnetism that results from the spins associated with the incomplete outer electronic shells (3d(9)) of the copper ions. Fluctuations of these spins give rise to magnetic excitations of the material, and might mediate the electron pairing that leads to superconductivity. If the mechanism for high-T-c superconductivity is the same for all copper oxide systems, their spin fluctuations should be universal. But so far, the opposite has seemed to be the case: neutron scattering data reveal clear differences between the spin fluctuations for two major classes of high-T-c materials, La2-xSrxCuO4 (refs 1-3) and YBa2Cu3O7-x (refs 4-6), whose respective building blocks are CuO2 layers and bilayers. Here we report two-dimensional neutron-scattering imaging of YBa2Cu3O6.6, which reveals that the low-frequency magnetic excitations are virtually identical to those of similarly doped La2-xSrxCuO4. Thus, the high-temperature (T-c less than or similar to 92 K) superconductivity of the former materials may be related to spatially coherent low-frequency spin excitations that were previously thought to be unique to the lower-T-c (<40 K) single-layer La2-xSrxCuO4 family. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. NEC Res Inst, Princeton, NJ 08540 USA. Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA. RP Mook, HA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Hayden, Stephen/F-4162-2011; Dai, Pengcheng /C-9171-2012 OI Hayden, Stephen/0000-0002-3209-027X; Dai, Pengcheng /0000-0002-6088-3170 NR 18 TC 291 Z9 291 U1 2 U2 24 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD OCT 8 PY 1998 VL 395 IS 6702 BP 580 EP 582 DI 10.1038/26931 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 127QW UT WOS:000076362900041 ER PT J AU Mardor, Y Aclander, J Alster, J Barton, D Bunce, G Carroll, A Christensen, N Courant, H Durrant, S Gushue, S Heppelmann, S Kosonovsky, E Mardor, I Marshak, M Makdisi, Y Minor, ED Navon, I Nicholson, H Piasetzky, E Roser, T Russell, J Sutton, CS Tanaka, M White, C Wu, JY AF Mardor, Y Aclander, J Alster, J Barton, D Bunce, G Carroll, A Christensen, N Courant, H Durrant, S Gushue, S Heppelmann, S Kosonovsky, E Mardor, I Marshak, M Makdisi, Y Minor, ED Navon, I Nicholson, H Piasetzky, E Roser, T Russell, J Sutton, CS Tanaka, M White, C Wu, JY TI Measurement of quasi-elastic C-12(p,2p) scattering at high momentum transfer SO PHYSICS LETTERS B LA English DT Article ID NUCLEAR TRANSPARENCY; TRANSVERSE-MOMENTUM AB We measured the high-momentum transfer [Q(2) = 4.8 and 6.2 (GeV/c)(2)] quasi-elastic C-12(p,2p) reaction at theta(cm) similar or equal to 90 degrees for 6 and 7.5 GeV/c incident protons. The momentum components of both outgoing protons and the missing energy and momentum of the proton in the nucleus were measured. We verified the validity of the quasi-elastic picture for ground state momenta up to about 0.5 GeV/c. Transverse and longitudinal momentum distributions of the target proton were measured. They have the same shape with a large momentum tail which is not consistent with independent particle models. We observed that the transverse distribution gets wider as the longitudinal component increases in the beam direction. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Tel Aviv Univ, Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Minnesota, Dept Phys, Minneapolis, MN 55455 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Massachusetts Dartmouth, Dept Phys, N Dartmouth, MA 02747 USA. RP Mardor, Y (reprint author), Tel Aviv Univ, Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. RI Marshak, Marvin/B-8645-2008 NR 16 TC 11 Z9 11 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 OCT 8 PY 1998 VL 437 IS 3-4 BP 257 EP 263 DI 10.1016/S0370-2693(98)01000-4 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 134FM UT WOS:000076732300005 ER PT J AU Vincent, SM Regan, PH Warner, DD Bark, RA Blumenthal, D Carpenter, MP Davids, CN Gelletly, W Janssens, RVF O'Leary, CD Lister, CJ Simpson, J Seweryniak, D Saitoh, T Schwartz, J Tormanen, S Juillet, O Nowacki, F Van Isacker, P AF Vincent, SM Regan, PH Warner, DD Bark, RA Blumenthal, D Carpenter, MP Davids, CN Gelletly, W Janssens, RVF O'Leary, CD Lister, CJ Simpson, J Seweryniak, D Saitoh, T Schwartz, J Tormanen, S Juillet, O Nowacki, F Van Isacker, P TI Competing T=0 and T=1 structures in the N=Z nucleus Ga-62(31) SO PHYSICS LETTERS B LA English DT Article DE isospin; N = Z; levels; shell model ID HIGH-SPIN STATES; SHELL-MODEL; NEUTRON; ARRAY; RB-74; BALL AB The low-lying levels in the odd-odd N = Z nucleus Ga-62 have been identified for the first time. These data reveal a cascade of stretched-E2 transitions based on a T = 0, 1(+) bandhead which decays directly to the T = 1, 0(+) ground state. The observed levels are interpreted in the context of the shell model, using as a basis, the pf(5/2)g(9/2) orbits with a Ni-56 core. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Surrey, Dept Phys, Guildford GU2 5XH, Surrey, England. SERC, Daresbury Lab, CCLRC, Warrington WA4 4AD, Cheshire, England. Niels Bohr Inst, Tandem Accelerator Lab, DK-4000 Roskilde, Denmark. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Staffordshire Univ, Sch Sci, Stoke On Trent ST4 2DE, Staffs, England. Yale Univ, AW Wright Nucl Struct Lab, New Haven, CT 06511 USA. Univ Jyvaskyla, Dept Phys, Jyvaskyla, Finland. GANIL, F-14076 Caen 5, France. Phys Theor Lab, F-67084 Strasbourg, France. RP Vincent, SM (reprint author), Univ Surrey, Dept Phys, Guildford GU2 5XH, Surrey, England. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 28 TC 63 Z9 63 U1 1 U2 4 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 OCT 8 PY 1998 VL 437 IS 3-4 BP 264 EP 272 DI 10.1016/S0370-2693(98)00994-0 PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 134FM UT WOS:000076732300006 ER PT J AU Bass, SD Brodsky, SJ Schmidt, I AF Bass, SD Brodsky, SJ Schmidt, I TI The spin structure of a polarized photon SO PHYSICS LETTERS B LA English DT Article ID DEPENDENT PARTON DISTRIBUTIONS; SUM-RULE; SCATTERING; QCD; ORDER AB We show that the first moment of the spin-dependent structure function g(1)(gamma)(x, Q(2)) of a real photon vanishes independent of the momentum transfer Q(2) it is probed with. This result is non-perturbative: it holds to all orders in perturbation theory in abelian and non-abelian gauge theory and at every twist. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Tecn Federico Santa Maria, Dept Fis, Valparaiso, Chile. RP Bass, SD (reprint author), Max Planck Inst Kernphys, Postfach 103980, D-69029 Heidelberg, Germany. EM Steven.Bass@mpi-hd.mpg.de; sjbth@slac.stanford.edu; ischmidt@newton.fis.utfsm.cl RI Schmidt, Ivan/J-5920-2012; OI Bass, Steven/0000-0002-2089-9661 NR 36 TC 33 Z9 33 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD OCT 8 PY 1998 VL 437 IS 3-4 BP 417 EP 424 DI 10.1016/S0370-2693(98)00917-4 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 134FM UT WOS:000076732300027 ER PT J AU Breitweg, J Derrick, M Krakauer, D Magill, S Mikunas, D Musgrave, B Repond, J Stanek, R Talaga, RL Yoshida, R Zhang, H Mattingly, MCK Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Coppola, N Corradi, M De Pasquale, S Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Eckert, M Grothe, M Hartmann, H Heinloth, K Heinz, L Hilger, E Jakob, HP Kappes, A Katz, UF Kerger, R Paul, E Pfeiffer, M Schnurbusch, H Wieber, H Bailey, DS Campbell-Robson, S Cottingham, WN Foster, B Hall-Wilton, R Heath, GP Heath, HF McFall, JD Piccioni, D Roff, DG Tapper, RJ Capua, M Iannotti, L Mastroberardino, A Schioppa, M Susinno, G Kim, JY Lee, JH Lim, IT Pac, MY Caldwell, A Cartiglia, N Jing, Z Liu, W Mellado, B Parsons, JA Ritz, S Sampson, S Sciulli, F Straub, PB Zhu, Q Borzemski, P Chwastowski, J Eskreys, A Figiel, J Klimek, K Przybycien, MB Zawiejski, L Adamczyk, L Bednarek, B Bukowy, M Czermak, AM Jelen, K Kisielewska, D Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Abbiendi, G Bauerdick, LAT Behrens, U Beier, H Bienlein, JK Desler, K Drews, G Fricke, U Gialas, I Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hasell, D Hebbel, K Johnson, KF Kasemann, M Koch, W Kotz, U Kowalski, H Lindemann, L Lohr, B Martinez, M Milewski, J Milite, M Monteiro, T Notz, D Pellegrino, A Pelucchi, F Piotrzkowski, K Rohde, M Roldan, J Ryan, JJ Saull, PRB Savin, AA Schneekloth, U Schwarzer, O Selonke, F Stonjek, S Surrow, B Tassi, E Westphal, D Wolf, G Wollmer, U Youngman, C Zeuner, W Burow, BD Coldewey, C Grabosch, HJ Meyer, A Schlenstedt, S Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Raach, H Trefzger, T Wolfle, S Bromley, JT Brook, NH Bussey, PJ Doyle, AT Lee, SW Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Strickland, E Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Garfagnini, A Gladilin, LK Kcira, D Klanner, R Lohrmann, E Poelz, G Zetsche, F Bacon, TC Butterworth, I Cole, JE Howell, G Lamberti, L Long, KR Miller, DB Pavel, N Prinias, A Sedgbeer, JK Sideris, D Walker, R Mallik, U Wang, SM Wu, JT Cloth, P Filges, D Fleck, JI Ishii, T Kuze, M Suzuki, I Tokushuku, K Yamada, S Yamauchi, K Yamazaki, E Hong, SJ Lee, SB Nam, SW Park, SK Lim, H Park, IH Son, D Barreiro, F Fernandez, JP Garcia, G Glasman, C Hernandez, JM Hervas, L Labarga, L del Peso, J Puga, J Terron, J de Troconiz, JF Corriveau, F Hanna, DS Hartmann, J Murray, WN Ochs, A Riveline, M Stairs, DG St-Laurent, M Tsurugai, T Bashkirov, V Dolgoshein, BA Stifutkin, A Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Verkerke, W Vossebeld, J Wiggers, L de Wolf, E Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Romanowski, TA Blaikley, HE Cashmore, RJ Cooper-Sarkar, AM Devenish, RCE Edmonds, JK Grosse-Knetter, J Harnew, N Nath, C Noyes, VA Quadt, A Ruske, O Tickner, JR Walczak, R Waters, DS Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dosselli, U Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Raso, M Hart, JC McCubbin, NA Shah, TP Epperson, D Keusch, C Rahn, JT Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Abramowicz, H Briskin, G Dagan, S Kananov, S Levy, A Abe, T Fusayasu, T Inuzuka, M Nagano, K Umemori, K Yamasita, T Hamatsu, R Hirose, T Homma, K Kitamura, S Matsushita, T Nishimura, T Arneodo, M Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Petrucci, MC Ruspa, M Sacchi, R Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Joo, KK Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, B Butterworth, JM Catterall, CD Hayes, ME Heaphy, EA Jones, TW Lane, JB Saunders, RL Sutton, MR Wing, M Ciborowski, J Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Deppe, O Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Dasu, S Foudas, C Loveless, RJ Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wodarczyk, M Deshpande, A Dhawan, S Hughes, VR Bhadra, S Frisken, WR Khakzad, M Schmidke, WB AF Breitweg, J Derrick, M Krakauer, D Magill, S Mikunas, D Musgrave, B Repond, J Stanek, R Talaga, RL Yoshida, R Zhang, H Mattingly, MCK Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Coppola, N Corradi, M De Pasquale, S Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Eckert, M Grothe, M Hartmann, H Heinloth, K Heinz, L Hilger, E Jakob, HP Kappes, A Katz, UF Kerger, R Paul, E Pfeiffer, M Schnurbusch, H Wieber, H Bailey, DS Campbell-Robson, S Cottingham, WN Foster, B Hall-Wilton, R Heath, GP Heath, HF McFall, JD Piccioni, D Roff, DG Tapper, RJ Capua, M Iannotti, L Mastroberardino, A Schioppa, M Susinno, G Kim, JY Lee, JH Lim, IT Pac, MY Caldwell, A Cartiglia, N Jing, Z Liu, W Mellado, B Parsons, JA Ritz, S Sampson, S Sciulli, F Straub, PB Zhu, Q Borzemski, P Chwastowski, J Eskreys, A Figiel, J Klimek, K Przybycien, MB Zawiejski, L Adamczyk, L Bednarek, B Bukowy, M Czermak, AM Jelen, K Kisielewska, D Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Abbiendi, G Bauerdick, LAT Behrens, U Beier, H Bienlein, JK Desler, K Drews, G Fricke, U Gialas, I Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hasell, D Hebbel, K Johnson, KF Kasemann, M Koch, W Kotz, U Kowalski, H Lindemann, L Lohr, B Martinez, M Milewski, J Milite, M Monteiro, T Notz, D Pellegrino, A Pelucchi, F Piotrzkowski, K Rohde, M Roldan, J Ryan, JJ Saull, PRB Savin, AA Schneekloth, U Schwarzer, O Selonke, F Stonjek, S Surrow, B Tassi, E Westphal, D Wolf, G Wollmer, U Youngman, C Zeuner, W Burow, BD Coldewey, C Grabosch, HJ Meyer, A Schlenstedt, S Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Raach, H Trefzger, T Wolfle, S Bromley, JT Brook, NH Bussey, PJ Doyle, AT Lee, SW Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Strickland, E Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Garfagnini, A Gladilin, LK Kcira, D Klanner, R Lohrmann, E Poelz, G Zetsche, F Bacon, TC Butterworth, I Cole, JE Howell, G Lamberti, L Long, KR Miller, DB Pavel, N Prinias, A Sedgbeer, JK Sideris, D Walker, R Mallik, U Wang, SM Wu, JT Cloth, P Filges, D Fleck, JI Ishii, T Kuze, M Suzuki, I Tokushuku, K Yamada, S Yamauchi, K Yamazaki, E Hong, SJ Lee, SB Nam, SW Park, SK Lim, H Park, IH Son, D Barreiro, F Fernandez, JP Garcia, G Glasman, C Hernandez, JM Hervas, L Labarga, L del Peso, J Puga, J Terron, J de Troconiz, JF Corriveau, F Hanna, DS Hartmann, J Murray, WN Ochs, A Riveline, M Stairs, DG St-Laurent, M Tsurugai, T Bashkirov, V Dolgoshein, BA Stifutkin, A Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Verkerke, W Vossebeld, J Wiggers, L de Wolf, E Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Romanowski, TA Blaikley, HE Cashmore, RJ Cooper-Sarkar, AM Devenish, RCE Edmonds, JK Grosse-Knetter, J Harnew, N Nath, C Noyes, VA Quadt, A Ruske, O Tickner, JR Walczak, R Waters, DS Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dosselli, U Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Raso, M Hart, JC McCubbin, NA Shah, TP Epperson, D Keusch, C Rahn, JT Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Abramowicz, H Briskin, G Dagan, S Kananov, S Levy, A Abe, T Fusayasu, T Inuzuka, M Nagano, K Umemori, K Yamasita, T Hamatsu, R Hirose, T Homma, K Kitamura, S Matsushita, T Nishimura, T Arneodo, M Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Petrucci, MC Ruspa, M Sacchi, R Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Joo, KK Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, B Butterworth, JM Catterall, CD Hayes, ME Heaphy, EA Jones, TW Lane, JB Saunders, RL Sutton, MR Wing, M Ciborowski, J Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Deppe, O Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Dasu, S Foudas, C Loveless, RJ Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wodarczyk, M Deshpande, A Dhawan, S Hughes, VR Bhadra, S Frisken, WR Khakzad, M Schmidke, WB CA ZEUS Collaboration TI Measurement of elastic Upsilon photoproduction at HERA SO PHYSICS LETTERS B LA English DT Article ID MESON PRODUCTION; ZEUS BARREL; J/PSI; COLLISIONS; DETECTOR; GEV/C; QCD AB The photoproduction reaction gamma p --> mu(+)mu(-) p has been studied in ep interactions using the ZEUS detector at HERA. The data sample corresponds to an integrated luminosity of 43.2 pb(-1). The Upsilon meson has been observed in photoproduction for the first time. The sum of the products of the elastic Upsilon(1S),Upsilon(2S),Upsilon(3S) photoproduction cross sections with their respective branching ratios is determined to be 13.3 +/- 6.0(stat.)(-2.3)(+2.7)(syst.) pb at a mean photon-proton centre of mass energy of 120 GeV. The cross section is above the prediction of a perturbative QCD model. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Andrews Univ, Berrien Springs, MI 49104 USA. Univ Bologna, Bologna, Italy. INFN Bologna, Bologna, Italy. Univ Bonn, Inst Phys, D-5300 Bonn, Germany. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Univ Calabria, Dept Phys, I-87036 Cosenza, Italy. Ist Nazl Fis Nucl, I-87036 Cosenza, Italy. Chonnam Natl Univ, Kwangju, South Korea. Columbia Univ, Nevis Labs, Irvington, NY USA. Inst Nucl Phys, Krakow, Poland. Jagiellonian Univ, Dept Phys, Krakow, Poland. DESY, D-2000 Hamburg, Germany. DESY, IfH, Zeuthen, Germany. Univ Florence, Florence, Italy. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Freiburg, Fak Phys, D-7800 Freiburg, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow, Lanark, Scotland. Univ Hamburg, Inst Exp Phys 1, Hamburg, Germany. Univ Hamburg, Inst Exp Phys 2, Hamburg, Germany. Imperial Coll London, High Energy Nucl Phys Grp, London, England. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Forschungszentrum Julich, Inst Kernphys, D-5170 Julich, Germany. Natl Lab High Energy Phys, KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki 305, Japan. Korea Univ, Seoul 136701, South Korea. Kyungpook Natl Univ, Taegu 702701, South Korea. Univ Autonoma Madrid, Dept Fis Teor, Madrid, Spain. McGill Univ, Dept Phys, Montreal, PQ, Canada. Meiji Gakuin Univ, Fac Gen Educ, Yokohama, Kanagawa, Japan. Moscow Engn Phys Inst, Moscow 115409, Russia. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow, Russia. NIKHEF, Amsterdam, Netherlands. Univ Amsterdam, Amsterdam, Netherlands. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Oxford, Dept Phys, Oxford, England. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Padua, Italy. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Polytech Univ, Sagamihara, Kanagawa, Japan. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Rome, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys, IL-69978 Tel Aviv, Israel. Univ Tokyo, Dept Phys, Tokyo 113, Japan. Tokyo Metropolitan Univ, Dept Phys, Tokyo, Japan. Univ Turin, Dipartimento Fis Sperimentale, Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Turin, Fac Sci 2, Alessandria, Italy. Ist Nazl Fis Nucl, Alessandria, Italy. Univ Toronto, Dept Phys, Toronto, ON, Canada. UCL, Dept Phys & Astron, London, England. Warsaw Univ, Inst Expt Phys, Warsaw, Poland. Inst Nucl Studies, PL-00681 Warsaw, Poland. Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT USA. York Univ, Dept Phys, N York, ON M3J 1P3, Canada. CNR, IROE, I-50127 Florence, Italy. RP Breitweg, J (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Solomin, Anatoly/C-3072-2016; Katz, Uli/E-1925-2013; Wiggers, Leo/B-5218-2015; Hernandez Calama, Jose Maria/H-9127-2015; Tassi, Enrico/K-3958-2015; Gladilin, Leonid/B-5226-2011; Morandin, Mauro/A-3308-2016; De Pasquale, Salvatore/B-9165-2008; Wing, Matthew/C-2169-2008; Bashkirov, Vladimir/A-4818-2008; Doyle, Anthony/C-5889-2009; Golubkov, Yury/E-1643-2012; Proskuryakov, Alexander/J-6166-2012 OI Kasemann, Matthias/0000-0002-0429-2448; Arneodo, Michele/0000-0002-7790-7132; Abbiendi, Giovanni/0000-0003-4499-7562; Martinez Rodriguez, Manel/0000-0002-9763-9155; Chwastowski, Janusz/0000-0002-6190-8376; Katz, Uli/0000-0002-7063-4418; Wiggers, Leo/0000-0003-1060-0520; Hernandez Calama, Jose Maria/0000-0001-6436-7547; Gladilin, Leonid/0000-0001-9422-8636; Morandin, Mauro/0000-0003-4708-4240; De Pasquale, Salvatore/0000-0001-9236-0748; Doyle, Anthony/0000-0001-6322-6195; NR 33 TC 90 Z9 91 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD OCT 8 PY 1998 VL 437 IS 3-4 BP 432 EP 444 DI 10.1016/S0370-2693(98)01081-8 PG 13 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 134FM UT WOS:000076732300029 ER PT J AU Yang, H Asplund, MC Kotz, KT Wilkens, MJ Frei, H Harris, CB AF Yang, H Asplund, MC Kotz, KT Wilkens, MJ Frei, H Harris, CB TI Reaction mechanism of silicon-hydrogen bond activation studied using femtosecond to nanosecond IR spectroscopy and ab initio methods SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TRANSITION-METAL ATOMS; ULTRAFAST INFRARED-SPECTROSCOPY; EFFECTIVE CORE POTENTIALS; OXIDATIVE ADDITION; ORGANOMETALLIC REACTIONS; TRISUBSTITUTED SILANES; MOLECULAR CALCULATIONS; PERTURBATION-THEORY; ENERGY SURFACE; GAS-PHASE AB The SI-H bond activation reactions by group VIIB, d(6) organometallic compounds eta(5)-CpM(CO)(3) (M = Mn. Re; Cp = Cs Hs) were studied in neat triethylsilane under ambient conditions. Utilizing femtosecond and nanosecond pump-probe spectroscopic methods, the spectral evolution of the CO stretching bands was monitored from 300 fs to tens of microseconds following UV photolysis. The reactive intermediates observed on the ultrafast time scale were also studied using ab initio quantum chemical modeling. It was found that photolysis of the manganese tricarbonyl resulted in dicarbonyls in their singlet or triplet electronic states, whereas photolysis of the rhenium complex led only to the singlet dicarbonyl. The branching ratio of the two manganese intermediates was measured and was related to different electronic excited states. For both the Mn and Re complexes, the reactions were found to be divided into two pathways of distinct time scales by the initial solvation of the dicarbonyls through the Si-H bond or an ethyl group of the solvent molecule. The time scale for the SI-H bond-breaking process was, for the first time, experimentally derived to be 4.4 ps, compared to 230 ns for breaking an alkane C-H bond. Knowledge of the elementary reaction steps including changes in molecular morphology and electronic multiplicity allowed a comprehensive description of the reaction mechanisms for these reactions. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, MS Calvin Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Harris, CB (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Wilkens, Matthew/I-3720-2014; OI Wilkens, Matthew/0000-0001-6749-9318; Yang, Haw/0000-0003-0268-6352 NR 59 TC 66 Z9 66 U1 2 U2 27 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 OCT 7 PY 1998 VL 120 IS 39 BP 10154 EP 10165 DI 10.1021/ja980692f PG 12 WC Chemistry, Multidisciplinary SC Chemistry GA 127ZP UT WOS:000076381000020 ER PT J AU Krueger, JK Zhi, G Stull, JT Trewhella, J AF Krueger, JK Zhi, G Stull, JT Trewhella, J TI Neutron-scattering studies reveal further details of the Ca2+/calmodulin-dependent activation mechanism of myosin light chain kinase SO BIOCHEMISTRY LA English DT Article ID DEPENDENT PROTEIN-KINASE; X-RAY-SCATTERING; INTRASTERIC REGULATION; CATALYTIC SUBUNIT; PEPTIDE COMPLEX; TROPONIN-C; CALMODULIN; BINDING; SUBSTRATE; CRYSTAL AB Previously, we utilized small-angle X-ray scattering and neutron scattering with contrast variation to obtain the first low-resolution structure of 4Ca(2+). calmodulin (CaM) complexed with a functional enzyme, an enzymatically active truncation mutant of skeletal muscle myosin light chain kinase (MLCK). These experiments showed that, upon binding to MLCK, CaM undergoes a conformational collapse identical to that observed when CaM binds to the isolated peptide corresponding to the CaM binding sequence of MLCK. CaM thereby was shown to release the inhibition of the kinase by inducing a significant movement of its CaM binding and autoinhibitory sequences away from the surface of the catalytic core [Krueger, J. K., Olah, G. A., Rokop, S. E., Zhi, G., Stull, J. T., and Trewhella, J. (1997) Biochemistry 36, 6017-6023]. We report here similar scattering experiments on the CaM MLCK complex with the addition of substrates; a nonhydrolyzable analogue of adenosine-triphosphate, AMPPNP, and a peptide substrate for MLCK, a phosphorylation sequence from myosin regulatory light chain (pRLC). These substrates are shown to induce an overall compaction of the complex. The separation of the centers-of-mass of the CaM and MLCK components is shortened (by similar to 12 Angstrom), thus bringing CaM closer to the catalytic site compared to the complex without substrates. In addition, there appears to be a reorientation of CaM with respect to the kinase upon substrate binding that results in interactions between the N-terminal sequence of CaM and the kinase that were not observed in the complex without substrates. Finally, the kinase itself becomes more compact in the CaM MLCK pRLC AMPPNP complex compared to the complex without substrates. This observed compaction of MLCK upon substrate binding is similar to that arising from the closure of the catalytic cleft in cAMP-dependent protein kinase upon binding pseudosubstrate. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Univ Texas, SW Med Ctr, Dept Physiol, Dallas, TX 75235 USA. RP Trewhella, J (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Mail Stop G758, Los Alamos, NM 87545 USA. RI Krueger, Joanna/A-3110-2011; OI Trewhella, Jill/0000-0002-8555-6766 FU NHLBI NIH HHS [HL06296, HL26043]; NIGMS NIH HHS [GM40528] NR 30 TC 41 Z9 42 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 OCT 6 PY 1998 VL 37 IS 40 BP 13997 EP 14004 DI 10.1021/bi981311d PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 128AW UT WOS:000076383900010 PM 9760234 ER PT J AU Groves, WA Zellers, ET Frye, GC AF Groves, WA Zellers, ET Frye, GC TI Analyzing organic vapors in exhaled breath using a surface acoustic wave sensor array with preconcentration: Selection and characterization of the preconcentrator adsorbent SO ANALYTICA CHIMICA ACTA LA English DT Article DE organic vapors; surface acoustic wave sensor array; preconcentrator adsorbent ID PATTERN-RECOGNITION; ADSORPTION CAPACITY; MODEL; MIXTURES; TEMPERATURE; RESPONSES; SOLVENTS; CHARCOAL; KINETICS; HUMIDITY AB The analysis of organic vapors in exhaled breath can provide information about chemical exposures and health status. This article describes work aimed at developing a small prototype instrument that employs an array of four polymer-coated surface acoustic wave (SAW) sensors and a thermally desorbable adsorbent preconcentrator for rapid breath analysis. The adsorbent used in the preconcentrator is critical to achieving adequate sensitivity and compensating for the high background of water vapor. Eight granular adsorbents packed into narrow bore glass tubes wrapped with NiCr wire were evaluated individually and in selected dual-bed configurations with respect to the pressure drop of the packed bed, retention of water vapor, and adsorption/desorption efficiency of each of several organic solvent vapors. Although adsorbents of Tenax GR((R)) and Carbotrap((R)) performed well, a highly porous styrene-divinylbenzene resin demonstrated superior overall performance and was selected for further testing. Solvents ranging in vapor pressure from smm of Hg (m-xylene) to 420 mm of Hg (dichloromethane) were efficiently trapped from 0.25-1 spiked breath samples and efficiently desorbed at 170 degrees C. incorporating an intermediate dry-air purge step prior to thermal desorption of samples selectively removed co-adsorbed water and reduced the limits of detection (LOD) by an order of magnitude. Results of detailed breakthrough studies were considered in the context of the modified Wheeler and Langmuir adsorption models and used to determine the minimum quantity of adsorbent required to prevent saturation of the adsorbent bed for each test vapor. Measurement of vapors at concentrations ranging from sub-ppm to 200 ppm was demonstrated. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Michigan, Dept Environm & Ind Hlth, Ann Arbor, MI 48109 USA. Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. Sandia Natl Labs, Microsensor Res & Dev Dept, Albuquerque, NM 87185 USA. RP Groves, WA (reprint author), Univ Iowa, Dept Prevent Med & Environm Hlth, 100 Oakdale Campus,136 IREH, Iowa City, IA 52242 USA. EM william-groves@uiowa.edu NR 40 TC 98 Z9 98 U1 4 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0003-2670 J9 ANAL CHIM ACTA JI Anal. Chim. Acta PD OCT 5 PY 1998 VL 371 IS 2-3 BP 131 EP 143 DI 10.1016/S0003-2670(98)00294-3 PG 13 WC Chemistry, Analytical SC Chemistry GA 120KX UT WOS:000075956600002 ER PT J AU Liu, N Shih, CK Geisz, J Mascarenhas, A Olson, JM AF Liu, N Shih, CK Geisz, J Mascarenhas, A Olson, JM TI Alloy ordering in GaInP alloys: A cross-sectional scanning tunneling microscopy study SO APPLIED PHYSICS LETTERS LA English DT Article ID LONG-RANGE ORDER; SEMICONDUCTOR ALLOYS; BAND-GAP; GA0.5IN0.5P AB We present a cross-sectional scanning tunneling microscopy (XSTM) study of the spontaneous ordering of Ga0.48In0.52P and Ga0.52In0.48P grown on (001) GaAs substrates by molecular beam epitaxy (MBE) and organometallic vapor phase epitaxy (OMVPE), respectively. The (111)-type alloy ordering could be seen clearly in the OMVPE-grown alloy region. On the other hand, the MBE-grown region shows a very small degree of ordering as revealed by the STM. Most of the ordered region shows (InP)(1)(GAP)(1)-type ordering: alternating InP- and GaP-like ((1) over bar 11) planes. In addition to this type of ordering, we also observe another type of ordering consisting of two InP- like ((1) over bar 11) planes and one GaP-like ((1) over bar 11) plane that we call (InP)(2)(GAP)(1)-type ordering. (C) 1998 American Institute of Physics. [S0003-6951(98)00140-5]. C1 Univ Texas, Dept Phys, Austin, TX 78712 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Shih, CK (reprint author), Univ Texas, Dept Phys, Austin, TX 78712 USA. NR 16 TC 29 Z9 29 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 5 PY 1998 VL 73 IS 14 BP 1979 EP 1981 DI 10.1063/1.122341 PG 3 WC Physics, Applied SC Physics GA 124LF UT WOS:000076183300019 ER PT J AU Agarwal, A Gossmann, HJ Jacobson, DC Eaglesham, DJ Sosnowski, M Poate, JM Yamada, I Matsuo, J Haynes, TE AF Agarwal, A Gossmann, HJ Jacobson, DC Eaglesham, DJ Sosnowski, M Poate, JM Yamada, I Matsuo, J Haynes, TE TI Transient enhanced diffusion from decaborane molecular ion implantation SO APPLIED PHYSICS LETTERS LA English DT Article ID SILICON; EPITAXY; FILMS AB Transient enhanced diffusion (TED) from implantation of 5 keV B10H14 and 0.5 keV B ions has been quantified and compared for nominal boron doses of 10(14) and 10(15) cm(-2). Boron diffusivity during annealing was extracted from secondary ion mass spectroscopy depth profiles of diffused marker layers in boron doping-superlattices and the actual implanted B dose was independently measured by nuclear reaction analysis. Comparable enhancements were observed from both ions. Transmission electron microscopy analysis revealed that both boron- and decaborane-implanted samples were amorphized at a nominal 10(15) cm(-2) B dose. A comparison with data from low energy Si implants revealed a similar dependence of diffusivity enhancement on implant dose. These findings are consistent with the understanding that TED is caused by the interstitial supersaturation resulting from a number of excess interstitials approximately equal to the number of implanted atoms which can become substitutional in the silicon lattice. Accordingly, no contribution to TED is expected from the hydrogen in the B10H14 ions and none is observed. Furthermore, there is no detectable effect in the diffusion profiles which can be attributed to a difference in the ion damage produced by the decaborane molecule and the boron atom. In both cases the reduction in diffusivity enhancement is due only to proximity of the implantation-induced excess interstitials to the wafer surface. (C) 1998 American Institute of Physics. [S0003-6951(98)04240-5]. C1 AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. New Jersey Inst Technol, Newark, NJ 07102 USA. Kyoto Univ, Sakyo Ku, Kyoto 60601, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Agarwal, A (reprint author), Eaton Corp, 55 Cherry Hill Dr, Beverly, MA 01915 USA. RI Haynes, Tony/P-8932-2015 OI Haynes, Tony/0000-0003-2871-4745 NR 13 TC 21 Z9 21 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 5 PY 1998 VL 73 IS 14 BP 2015 EP 2017 DI 10.1063/1.122353 PG 3 WC Physics, Applied SC Physics GA 124LF UT WOS:000076183300031 ER PT J AU Zhang, Z Hammel, PC Midzor, M Roukes, ML Childress, JR AF Zhang, Z Hammel, PC Midzor, M Roukes, ML Childress, JR TI Ferromagnetic resonance force microscopy on microscopic cobalt single layer films SO APPLIED PHYSICS LETTERS LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE AB We report mechanical detection of ferromagnetic resonance (FMR) signals from microscopic Co single layer thin films using a magnetic resonance force microscope (MRFM). Variations in the magnetic anisotropy field and the inhomogeneity of were clearly observed in the FMR spectra of microscopic Co thin films 500 and 1000 Angstrom thick and similar to 40x200 mu m(2) in lateral extent. This demonstrates the important potential that MRFM detection of FMR holds for microscopic characterization of spatial distribution of magnetic properties in magnetic layered materials and devices. (C) 1998 American Institute of Physics. [S0003-6951(98)01640-4]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CALTECH, Pasadena, CA 91125 USA. Univ Florida, Gainesville, FL 32611 USA. RP Hammel, PC (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Roukes, Michael/E-9787-2010; Hammel, P Chris/O-4845-2014 OI Hammel, P Chris/0000-0002-4138-4798 NR 13 TC 35 Z9 36 U1 1 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 5 PY 1998 VL 73 IS 14 BP 2036 EP 2038 DI 10.1063/1.122359 PG 3 WC Physics, Applied SC Physics GA 124LF UT WOS:000076183300038 ER PT J AU Wong, GCL Li, YL Koltover, I Safinya, CR Cai, ZH Yun, WB AF Wong, GCL Li, YL Koltover, I Safinya, CR Cai, ZH Yun, WB TI Mesoscopic structure of DNA-membrane self-assemblies: Microdiffraction and manipulation on lithographic substrates SO APPLIED PHYSICS LETTERS LA English DT Article AB Using microdiffraction techniques at the Advanced Photon Source, we have found evidence for local molecular alignment within the mesoscopic fibers of DNA-cationic membrane complexes, a system originally conceived as gene delivery vectors. Furthermore, these mesoscopic structures can be manipulated by using lithographically patterned microchannel arrays, so that the optical axes of individual fibers are aligned parallel to the channels. These observations suggest that DNA-membrane complexes may have additional technological applications, such as active electrophoretic media and templates for the fabrication of semiconductor superlattices and nanoporous materials with tunable pore sizes. (C) 1998 American Institute of Physics. [S0003-6951(98)00640-8]. C1 Univ Calif Santa Barbara, Dept Mat, Mat Res Lab, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Wong, GCL (reprint author), Univ Calif Santa Barbara, Dept Mat, Mat Res Lab, Santa Barbara, CA 93106 USA. OI Safinya, Cyrus/0000-0002-3295-7128 NR 9 TC 12 Z9 12 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 5 PY 1998 VL 73 IS 14 BP 2042 EP 2044 DI 10.1063/1.122361 PG 3 WC Physics, Applied SC Physics GA 124LF UT WOS:000076183300040 ER PT J AU Tucker, MD Barton, LL Thomson, BM AF Tucker, MD Barton, LL Thomson, BM TI Removal of U and Mo from water by immobilized Desulfovibrio desulfuricans in column reactors SO BIOTECHNOLOGY AND BIOENGINEERING LA English DT Article DE molybdenum; uranium; immobilized cells; dissimilatory reduction; Desulfovibrio ID DISSIMILATORY METAL REDUCTION; URANIUM; BIOREMEDIATION; SULFATE; ACCUMULATION; CELLS AB Intact cells of Desulfovibrio desulfuricans were immobilized in polyacrylamide gel and used to remove soluble U and Mo from water by enzymatically mediated reduction reactions in column reactors. Formate or lactate served as the electron donor and oxidized U(VI) and Mo(VI) species served as electron accepters. Greater than 99% removal efficiencies were achieved for both metals with initial concentrations of 5 mg/L U and 10 mg/L Mo. Hydraulic residence times in the columns were between 24 and 36 h. Sulfate concentrations as high as 2000 mg/L did not inhibit reduction of U or Mo in the columns. However, nitrate inhibited uranium reduction at concentrations near 50 mg/L and inhibited molybdenum reduction at concentrations near 150 mg/L. The results indicate that enzymatic reduction of U and Mo by immobilized cells of D. desulfuricans may be a practical method for removing these contaminants from solution in continuous-flow reactors. (C) 1998 John Wiley & Sons, Inc. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Biol, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Civil Engn, Albuquerque, NM 87131 USA. RP Tucker, MD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 30 TC 25 Z9 26 U1 1 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0006-3592 J9 BIOTECHNOL BIOENG JI Biotechnol. Bioeng. PD OCT 5 PY 1998 VL 60 IS 1 BP 88 EP 96 DI 10.1002/(SICI)1097-0290(19981005)60:1<88::AID-BIT10>3.0.CO;2-4 PG 9 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 114GH UT WOS:000075600400010 PM 10099409 ER PT J AU Xiang, XD AF Xiang, XD TI It's a materials world SO CHEMISTRY & INDUSTRY LA English DT Article ID COMBINATORIAL APPROACH; LUMINESCENT MATERIALS; OPTIMIZATION; DISCOVERY; LIBRARIES C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Xiang, XD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 2-300,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Xiang, Xiaodong/A-9445-2012 NR 18 TC 2 Z9 3 U1 0 U2 1 PU SOC CHEMICAL INDUSTRY PI LONDON PA 14 BELGRAVE SQUARE, LONDON SW1X 8PS, ENGLAND SN 0009-3068 J9 CHEM IND-LONDON JI Chem. Ind. PD OCT 5 PY 1998 IS 19 BP 800 EP 802 PG 3 WC Chemistry, Applied SC Chemistry GA 128FT UT WOS:000076395600031 ER PT J AU Bud'ko, SL Fontes, MB Baggio-Saitovitch, EM AF Bud'ko, SL Fontes, MB Baggio-Saitovitch, EM TI Evolution of physical properties in the Ce1-xLaxFeGe3 series: crossover from Kondo lattice to single ion Kondo impurity systems SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID HEAVY-FERMION SYSTEMS; FINITE CONCENTRATION; BEHAVIOR AB Evolution of the structural, magnetic, transport and magneto-transport properties of the Ce1-xLaxFeGe3 series is studied by powder x-ray diffraction, Fe-57 Mossbauer spectroscopy, magnetization and resistivity in zero and applied magnetic field. Changes from concentrated Kondo system-like (x less than or equal to 0.3) to single Kondo ion-like (x greater than or equal to 0.65) behaviour are observed. Magneto-resistivity behaviour in both regimes is discussed within the existing theoretical views which include non-negligible 'normal' metal contributions. C1 Ctr Brasileiro Pesquisas Fis, CNPq, BR-22290180 Rio De Janeiro, Brazil. RP Bud'ko, SL (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RI Saitovitch, Elisa/A-6769-2015 NR 23 TC 6 Z9 6 U1 1 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD OCT 5 PY 1998 VL 10 IS 39 BP 8815 EP 8828 DI 10.1088/0953-8984/10/39/017 PG 14 WC Physics, Condensed Matter SC Physics GA 129ZB UT WOS:000076493000017 ER PT J AU Anderson, JD Laing, PA Lau, EL Liu, AS Nieto, MM Turyshev, SG AF Anderson, JD Laing, PA Lau, EL Liu, AS Nieto, MM Turyshev, SG TI Indication, from Pioneer 10/11, Galileo, and Ulysses data, of an apparent anomalous, weak, long-range acceleration SO PHYSICAL REVIEW LETTERS LA English DT Article ID MATTER AB Radio metric data from the Pioneer 10/11, Galileo, and Ulysses spacecraft indicate an apparent anomalous, constant, acceleration acting on the spacecraft with a magnitude similar to 8.5 x 10(-8) cm/s(2), directed towards the Sun. Two independent codes and physical strategies have been used to analyze the data. A number of potential causes have been ruled out. We discuss future kinematic tests and possible origins of the signal. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Aerospace Corp, El Segundo, CA 90245 USA. Astrodynam Sci, Los Angeles, CA 90039 USA. Univ Calif Los Alamos Natl Lab, Div Theoret MSB285, Los Alamos, NM 87545 USA. RP Anderson, JD (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 18 TC 362 Z9 366 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 5 PY 1998 VL 81 IS 14 BP 2858 EP 2861 DI 10.1103/PhysRevLett.81.2858 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900006 ER PT J AU Spaltro, CM Bauer, TS Blok, HP Botto, T Cisbani, E De Leo, R Dodge, GE Ent, R Frullani, S Garibaldi, F Glockle, W Golak, J Harakeh, MN Iodice, M Jans, E Kamada, H Kasdorp, WJ Kormanyos, C Lapikas, L Misiejuk, A Nagorny, SI Nooren, GJ Onderwater, CJG Perrino, R van Sambeek, MJM Starink, R van der Steenhoven, G Tjon, J van Uden, MA Urciuoli, GM de Vries, H Witala, J Yeomans, DM AF Spaltro, CM Bauer, TS Blok, HP Botto, T Cisbani, E De Leo, R Dodge, GE Ent, R Frullani, S Garibaldi, F Glockle, W Golak, J Harakeh, MN Iodice, M Jans, E Kamada, H Kasdorp, WJ Kormanyos, C Lapikas, L Misiejuk, A Nagorny, SI Nooren, GJ Onderwater, CJG Perrino, R van Sambeek, MJM Starink, R van der Steenhoven, G Tjon, J van Uden, MA Urciuoli, GM de Vries, H Witala, J Yeomans, DM TI q and p(m) dependence of the He-3(e,e ' d)p reaction SO PHYSICAL REVIEW LETTERS LA English DT Article ID FINAL-STATE INTERACTIONS; ELECTRON-SCATTERING; COVARIANT APPROACH; FULL INCLUSION; HE-3; BREAKUP; SYSTEMS; LI-6 AB The cross section for the He-3(e, e'd)p reaction has been measured for a range of missing momentum p, at incident electron energies of 370 and 576 MeV and for values of the three-momentum transfer q of 412, 504, and 604 MeV/c. The longitudinal and transverse structure functions have been separated for q = 412 and 504 MeV/c. The data are compared to exact three-body Faddeev calculations and calculations based on a covariant, gauge-invariant diagrammatic expansion. In general, fair to good agreement is observed, but there are some differences between the data and the calculations, especially for the q dependence and for the transverse structure function W-T. C1 Free Univ Amsterdam, NL-1081 HV Amsterdam, Netherlands. NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Univ Utrecht, NL-3508 TA Utrecht, Netherlands. Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. Ist Nazl Fis Nucl, I-73100 Lecce, Italy. TJNAF, Newport News, VA 23606 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. Kernfys Versneller Inst, NL-9747 AA Groningen, Netherlands. RP Spaltro, CM (reprint author), Free Univ Amsterdam, de Boelelaan 1081, NL-1081 HV Amsterdam, Netherlands. RI Perrino, Roberto/B-4633-2010; Cisbani, Evaristo/C-9249-2011 OI Perrino, Roberto/0000-0002-5764-7337; Cisbani, Evaristo/0000-0002-6774-8473 NR 21 TC 13 Z9 13 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 5 PY 1998 VL 81 IS 14 BP 2870 EP 2873 DI 10.1103/PhysRevLett.81.2870 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900009 ER PT J AU Drewsen, M Brodersen, C Hornekaer, L Hangst, JS Schiffer, JP AF Drewsen, M Brodersen, C Hornekaer, L Hangst, JS Schiffer, JP TI Large ion crystals in a linear Paul trap SO PHYSICAL REVIEW LETTERS LA English DT Article ID LASER-COOLED IONS; ONE-COMPONENT PLASMA; STORAGE-RING; QUADRUPOLE; PHASE; TRANSITION; DYNAMICS; ORDER AB Plasmas of Mg+ ions, containing more than 10(5) ions, have been observed to reach well-ordered (crystalline) states by applying laser cooling. The crystals are highly elongated with up to ten concentric cylindrical shells surrounding a central string. Such large structures have not previously been observed in a Paul trap. The amplitude of the micromotion of the ions can be larger than the shell spacings. As the diameter changes along the crystals, sharp transitions are observed when new shells form, in good agreement with molecular dynamics simulations. The predictions from simulations of how ordering develops with decreasing temperature are also confirmed. C1 Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus, Denmark. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Chicago, Chicago, IL 60637 USA. RP Drewsen, M (reprint author), Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus, Denmark. NR 20 TC 168 Z9 168 U1 1 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 OCT 5 PY 1998 VL 81 IS 14 BP 2878 EP 2881 DI 10.1103/PhysRevLett.81.2878 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900011 ER PT J AU Blinov, BB Anferov, VA Derbenev, YS Kageya, T Krisch, AD Lorenzon, W Ratner, LG Sivers, DW Sourkont, KV Wong, VK Chu, CM Lee, SY Rinckel, T Schwandt, P Sperisen, F von Przewoski, B Sato, H AF Blinov, BB Anferov, VA Derbenev, YS Kageya, T Krisch, AD Lorenzon, W Ratner, LG Sivers, DW Sourkont, KV Wong, VK Chu, CM Lee, SY Rinckel, T Schwandt, P Sperisen, F von Przewoski, B Sato, H TI Spin flipping in the presence of a full Siberian snake SO PHYSICAL REVIEW LETTERS LA English DT Article ID DEPOLARIZING RESONANCE; BEAM AB We have demonstrated for the first time spin flipping of a polarized proton beam stored in a ring containing a nearly 100% Siberian snake; we did this using a "snake" depolarizing resonance induced by an rf solenoid magnet. By varying the rf solenoid's ramp time, frequency range, and voltage, we reached a spin-flip efficiency of about 91%. This spin-flip efficiency was probably reduced because the horizontal stable spin direction was not perpendicular to the longitudinal field of the rf solenoid, and was possibly reduced by nearby synchrotron sideband resonances. The planned use of a vertical rf dipole may improve the spin-flip efficiency. C1 Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. Indiana Univ, Cyclotron Facil, Bloomington, IN 47408 USA. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 3050801, Japan. DESY, D-2000 Hamburg, Germany. Brookhaven Natl Lab, Upton, NY 11973 USA. Portland Phys Inst, Portland, OR 97201 USA. Moscow State Univ, Moscow, Russia. RP Blinov, BB (reprint author), Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. NR 19 TC 27 Z9 28 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 OCT 5 PY 1998 VL 81 IS 14 BP 2906 EP 2909 DI 10.1103/PhysRevLett.81.2906 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900018 ER PT J AU Stoldt, CR Cadilhe, AM Jenks, CJ Wen, JM Evans, JW Thiel, PA AF Stoldt, CR Cadilhe, AM Jenks, CJ Wen, JM Evans, JW Thiel, PA TI Evolution of far-from-equilibrium nanostructures formed by cluster-step and cluster-cluster coalescence in metal films SO PHYSICAL REVIEW LETTERS LA English DT Article ID TUNNELING-MICROSCOPY; DIFFUSION; SURFACES AB Scanning tunneling microscopy experiments reveal the formation of a variety of geometrically exotic nanostructures following submonolayer deposition of Ag on Ag(100). These result from the diffusion of large Ag clusters, and their subsequent "collision" and coalescence with extended step edges, and with other clusters. Relaxation of these far-from-equilibrium step-edge configurations is monitored to determine rates for restructuring versus local geometry and feature size. This behavior is analyzed with lattice-gas model simulations to elucidate the underlying atomistic mass transport processes. C1 Iowa State Univ, Dept Chem, IPRT, Ames, IA 50011 USA. Iowa State Univ, Dept Math, IPRT, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Stoldt, CR (reprint author), Iowa State Univ, Dept Chem, IPRT, Ames, IA 50011 USA. RI Cadilhe, Antonio/G-1479-2016 OI Cadilhe, Antonio/0000-0002-0252-6992 NR 16 TC 54 Z9 54 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 5 PY 1998 VL 81 IS 14 BP 2950 EP 2953 DI 10.1103/PhysRevLett.81.2950 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900029 ER PT J AU Fast, L Eriksson, O Johansson, B Wills, JM Straub, G Roeder, H Nordstrom, L AF Fast, L Eriksson, O Johansson, B Wills, JM Straub, G Roeder, H Nordstrom, L TI Theoretical aspects of the charge density wave in uranium SO PHYSICAL REVIEW LETTERS LA English DT Article ID CRYSTAL-STRUCTURE STABILITIES; PRESSURE; SYSTEMS; CERIUM; BAND AB Using a first principles total energy method, we have reproduced the observed charge density wave (CDW) state of alpha-uranium (called alpha(1)). This CDW is found to be a result of a Peierls-like transition, i.e., by opening of partial gaps at the Fermi level. The part of the Fermi surface affected by the distortion shows a strong nesting of fairly narrow f bands. In addition we suggest that the slightly modified alpha(1) CDW state, which is called alpha(2) and is observed by cooling the alpha(1) phase, is caused by a closely related mechanism, namely, by a nesting of the Fermi surface in the b direction. This is consistent with the observed CDW ordering. C1 Uppsala Univ, Dept Phys, Condensed Matter Theory Grp, S-75121 Uppsala, Sweden. Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87544 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87544 USA. RP Uppsala Univ, Dept Phys, Condensed Matter Theory Grp, Box 530, S-75121 Uppsala, Sweden. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 20 TC 50 Z9 50 U1 6 U2 15 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 OCT 5 PY 1998 VL 81 IS 14 BP 2978 EP 2981 DI 10.1103/PhysRevLett.81.2978 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900036 ER PT J AU Kogan, S AF Kogan, S TI Random telegraph noise in microstructures SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM POINT CONTACTS AB The theory of random current switchings in conductors with S-type current-voltage characteristic is presented. In the range of bistability, the mean time spent by the system in the low-current state before a transition to the high-current state occurs, <(tau)over bar>(l), decreases with voltage, and that for the high-current state, <(tau)over bar>(h), grows with voltage; both variations are exponential-like. <(tau)over bar>(l) = <(tau)over bar>(h) at a definite voltage in the bistability range. These results are in full accordance with experiments on microstructures. Because of the growth of both times with the size of the conductor, such noise is observable just in microstructures. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kogan, S (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 14 TC 10 Z9 10 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 5 PY 1998 VL 81 IS 14 BP 2986 EP 2989 DI 10.1103/PhysRevLett.81.2986 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900038 ER PT J AU McKee, RA Walker, FJ Chisholm, MF AF McKee, RA Walker, FJ Chisholm, MF TI Crystalline oxides on silicon: The first five monolayers SO PHYSICAL REVIEW LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; THIN-FILMS; GROWTH; MAGNETORESISTANCE; TEMPERATURE; STABILITY AB The long-standing problem of growing a commensurate crystalline oxide interface with silicon has been solved. Alkaline earth and perovskite oxides can be grown in perfect registry on the (001) face of silicon, totally avoiding the amorphous silica phase that ordinarily forms when silicon is exposed to an oxygen containing environment. The physics of the heteroepitaxy lies in establishing a sequenced transition that uniquely addresses the thermodynamics of a layer-by-layer energy minimization at the interface. A metal-oxide-semiconductor capacitor using SrTiO3 as an alternative to SiO2 yields the extraordinary result of t(eq) < 10 Angstrom. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP McKee, RA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Walker, Frederick/0000-0002-8094-249X NR 28 TC 707 Z9 719 U1 18 U2 135 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 OCT 5 PY 1998 VL 81 IS 14 BP 3014 EP 3017 DI 10.1103/PhysRevLett.81.3014 PG 4 WC Physics, Multidisciplinary SC Physics GA 125HR UT WOS:000076231900045 ER PT J AU Asmis, KR Taylor, TR Neumark, DM AF Asmis, KR Taylor, TR Neumark, DM TI Anion photoelectron spectroscopy of BN- SO CHEMICAL PHYSICS LETTERS LA English DT Article ID EXCITED-STATES; GROUND-STATE; TRANSITION; MOLECULE; PHOTODETACHMENT; MULTIREFERENCE; SPECTRA AB Photoelectron spectra of the BN- anion at 266 nm and 355 nm are reported. We observe transitions to the ground and three lowest excited states of BN. The electron affinity of BN (X(3)Pi) is 3.160 +/- 0.005 eV. Spectroscopic constants for the anion (X(2)Sigma(+)) are r(e) = 1.284 +/- 0.005 Angstrom, omega(e) = 1660 +/- 40 cm(-1) and omega(e)chi(e) = 12 +/- 4 cm(-1). Term energies T-0 for the excited states of BN are 0.031 +/- 0.004 eV (a(1)Sigma(+)), 0.468 +/- 0.004 eV (b(1)Pi) and 1.221 +/- 0.006 eV (A(3)Sigma(+)). (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Neumark, DM (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Asmis, Knut/N-5408-2014; Neumark, Daniel/B-9551-2009 OI Asmis, Knut/0000-0001-6297-5856; Neumark, Daniel/0000-0002-3762-9473 NR 25 TC 32 Z9 32 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD OCT 2 PY 1998 VL 295 IS 1-2 BP 75 EP 81 DI 10.1016/S0009-2614(98)00943-9 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 126CT UT WOS:000076275900011 ER PT J AU Yartys, VA Gingl, F Yvon, K Akselrud, LG Kolomietz, AV Havela, L Vogt, T Harris, IR Hauback, BC AF Yartys, VA Gingl, F Yvon, K Akselrud, LG Kolomietz, AV Havela, L Vogt, T Harris, IR Hauback, BC TI Hydrogen sorption properties of intermetallic TbNiAl and crystal structure of TbNiAlD1.1 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Letter DE metal hydride; hydrogen sorption; structure refinement; neutron diffraction ID HYDRIDE AB Hydrogenation (deuteration) of intermetallic TbNiAl with ZrNiAl type crystal structure has been studied by differential thermal analysis and X-ray and neutron powder diffraction. The compound absorbs up to 1.4 hydrogen (deuterium) atoms per formula unit at room temperature and atmospheric pressure, and desorbs hydrogen under vacuum in a multistep reaction at about 105 degrees C, 160 degrees C and 320 degrees C, and deuterium at about 190 degrees C and 450 degrees C. Hydrogenation (deuteration) leads to an orthorhombic distortion of the hexagonal host structure; TbNiAlH1.4: a(similar to c(hex))=3.7204(7); b(similar to a(hex)root 3)=17.353(2) Angstrom; c (similar to a(hex))=7.636(1) Angstrom; TbNiALD(1.1): a=3.70187(8); b=12.4011(3); c=7.6075(7) Angstrom; space group Amm2. Three sorts of deuterium sites exist of which two have aluminium in their co-ordination polyhedra: trigonal bi-pyramidal [Tb3Ni2] (88% occupancy) and two tetrahedral [Tb2NiAl] (67% and 10% occupancy). The metal-deuterium bond distances are Tb-D=2.18-2.42 Angstrom, Ni-D=1.50-1.90 Angstrom, and Al-D=1.64-1.85 Angstrom. The deuterium-deuterium contact distances are all greater than 1.98 Angstrom. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Natl Acad Sci Ukraine, Karpenko Phys Mech Inst, Metal Hydrides Dept, UA-290601 Lviv, Ukraine. Inst Energy Technol, N-2007 Kjeller, Norway. Univ Geneva, Lab Cristallog, CH-1211 Geneva, Switzerland. Lviv State Univ, Inst Inorgan Chem, Lviv, Ukraine. Charles Univ, Dept Met Phys, CR-12116 Prague 2, Czech Republic. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Birmingham, Sch Met & Mat, Birmingham B15 2TT, W Midlands, England. RP Yartys, VA (reprint author), Natl Acad Sci Ukraine, Karpenko Phys Mech Inst, Metal Hydrides Dept, 5 Naukova Str, UA-290601 Lviv, Ukraine. RI Vogt, Thomas /A-1562-2011 OI Vogt, Thomas /0000-0002-4731-2787 NR 13 TC 12 Z9 12 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD OCT 2 PY 1998 VL 279 IS 2 BP L4 EP L7 DI 10.1016/S0925-8388(97)00610-5 PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 131MM UT WOS:000076579900002 ER PT J AU Broyles, BS Shalliker', RA Cherrak, DE Guiochon, G AF Broyles, BS Shalliker', RA Cherrak, DE Guiochon, G TI Visualization of viscous fingering in chromatographic columns SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE viscous fingering; preparative chromatography ID SIZE-EXCLUSION CHROMATOGRAPHY; VISCOSITY; SAMPLE AB A 17 mm I.D. glass column, packed with YMC-15 (spherical C-18 silica, 30 mu m particles) as the stationary phase and used with carbon tetrachloride as the mobile phase provided a suitable system for the visual observation of viscous fingering inside the packed bed, after the cylindrical lens effect had been canceled. Such a system appears nearly transparent due to the close matching of the refractive indices of the mobile and the stationary phases. The profiles of the bands obtained upon the injection of a flat pulses of a solvent of different refractive index were readily observed. On-column detection using a 35 mm photographic camera was employed for the direct recording of band profiles. A toluene UV marker was used to record subsequent elution profiles via UV detection. The influence of the sample viscosity, the mobile phase flow-rate, and the injection volume on the extent of viscous fingering and band broadening were studied. Viscous fingering was shown to increase with increasing difference between the viscosity of the sample injected and the mobile phase. Viscous fingers were more clearly delineated at higher flow-rates, but band distortion was observed even at flow-rates as low as 0.2 ml min(-1). The degree of band distortion was observed to increase with increasing volume injected. Finally, viscous fingering was found to be a reversible process, as previously reported. (C) 1998 Elsevier Science B.V All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Dept Chem, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Analyt Sci Div, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 24 TC 58 Z9 60 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 OCT 2 PY 1998 VL 822 IS 2 BP 173 EP 187 DI 10.1016/S0021-9673(98)00568-8 PG 15 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 131ZD UT WOS:000076604400001 ER PT J AU Mo, S Peiner, E Schlachetzki, A Klockenbrink, R Weber, ER AF Mo, S Peiner, E Schlachetzki, A Klockenbrink, R Weber, ER TI Selected-area electron-channeling pattern as a characterization method for heteroepitaxial layers SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article DE electron-channeling pattern; III/V-compound semiconductor on Si; lattice-mismatched epitaxy; spectroscopic ellipsometry ID BEAM EPITAXIAL GAAS; OPTICAL-ABSORPTION; SI; FILMS; INP; DISLOCATIONS; TEMPERATURE; GROWTH AB Strongly mismatched III/V-compound semiconductor heteroepitaxial layers on Si were investigated with respect to their crystal quality by quantitative analysis of selected-area electron-channeling patterns (SAECP). An algorithm, based on the statistical analysis of 2-D SAECPs using digital image processing, is described. Agreement is found between the crystal quality of the thin nucleation layers obtained by SAECP and the density of structural defects as determined by spectroscopic ellipsometry. Furthermore, an area-selectively thinned InP/Si sample was examined by SAECP to obtain the dislocation density versus the residual layer thickness. The dislocation-density distribution agrees well with the theoretical prediction and experimental reference data. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Tech Univ Braunschweig, Inst Semicond Technol, D-38023 Braunschweig, Germany. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci, Berkeley, CA 94720 USA. RP Schlachetzki, A (reprint author), Tech Univ Braunschweig, Inst Semicond Technol, POB 3329, D-38023 Braunschweig, Germany. NR 27 TC 2 Z9 2 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 OCT 2 PY 1998 VL 56 IS 1 BP 37 EP 42 DI 10.1016/S0921-5107(98)00254-2 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 137BD UT WOS:000076892800006 ER PT J AU Madia, WJ AF Madia, WJ TI A call for more science in EPA regulations SO SCIENCE LA English DT Editorial Material C1 Pacific NW Lab, Richland, WA 99352 USA. RP Madia, WJ (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD OCT 2 PY 1998 VL 282 IS 5386 BP 45 EP 45 DI 10.1126/science.282.5386.45 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 126LM UT WOS:000076294900017 PM 9786793 ER PT J AU Neumann, AU Lam, NP Dahari, H Gretch, DR Wiley, TE Layden, TJ Perelson, AS AF Neumann, AU Lam, NP Dahari, H Gretch, DR Wiley, TE Layden, TJ Perelson, AS TI Hepatitis C viral dynamics in vivo and the antiviral efficacy of interferon-alpha therapy SO SCIENCE LA English DT Article ID VIRUS-INFECTION; RAPID TURNOVER; IN-VIVO; ALFA; LYMPHOCYTES; CLEARANCE; VIRIONS AB To better understand the dynamics of hepatitis C virus and the antiviral effect of interferon-alpha-2b (IFN), viral decline in 23 patients during therapy was analyzed with a mathematical model. The analysis indicates that the major initial effect of IFN is to block virion production or release, with blocking efficacies of 81, 95, and 96% for daily doses of 5, 10, and 15 million international units, respectively. The estimated virion half-life (t(1/2)) was, on average, 2.7 hours, with pretreatment production and clearance of 10(12) virions per day. The estimated infected cell death rate exhibited large interpatient variation (corresponding t(1/2) = 1.7 to 70 days), was inversely correlated with baseline viral load, and was positively correlated with alanine aminotransferase levels. Fast death rates were predictive of virus being undetectable by polymerase chain reaction at 3 months. These findings show that infection with hepatitis C virus is highly dynamic and that early monitoring of viral load can help guide therapy. C1 Univ Illinois, Dept Pharm Practice, Chicago, IL 60612 USA. Bar Ilan Univ, Dept Life Sci, IL-52900 Ramat Gan, Israel. Santa Fe Inst, Santa Fe, NM 87501 USA. Univ Washington, Hepatatis Lab, Seattle, WA 98144 USA. Univ Illinois, Dept Med, Sect Digest & Liver Dis, Chicago, IL 60612 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Neumann, AU (reprint author), Univ Illinois, Dept Pharm Practice, Chicago, IL 60612 USA. RI Cheng, Yushao/E-6256-2011 FU NCRR NIH HHS [RR06555]; NIDDK NIH HHS [A1/DK41320-2]; PHS HHS [A139049-2] NR 33 TC 1429 Z9 1479 U1 3 U2 43 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD OCT 2 PY 1998 VL 282 IS 5386 BP 103 EP 107 DI 10.1126/science.282.5386.103 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 126LM UT WOS:000076294900048 PM 9756471 ER PT J AU Werst, DW Trifunac, AD AF Werst, DW Trifunac, AD TI Observation of radical cations by swiftness or by stealth SO ACCOUNTS OF CHEMICAL RESEARCH LA English DT Review ID ELECTRON-SPIN-RESONANCE; DETECTED MAGNETIC-RESONANCE; LIQUID HYDROCARBONS; IONIZING-RADIATION; OPTICAL-DETECTION; QUADRICYCLANE; MATRICES; ZEOLITES; ZSM-5; IONS C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Werst, DW (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 37 TC 10 Z9 10 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0001-4842 J9 ACCOUNTS CHEM RES JI Accounts Chem. Res. PD OCT PY 1998 VL 31 IS 10 BP 651 EP 657 DI 10.1021/ar970234w PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 133FY UT WOS:000076677200006 ER PT J AU Olken, F Jacobsen, HA McParland, C Piette, MA Anderson, MF AF Olken, F Jacobsen, HA McParland, C Piette, MA Anderson, MF TI Object lessons learned from a distributed system for remote building monitoring and operation SO ACM SIGPLAN NOTICES LA English DT Article AB In this paper we describe our experiences with the design, the deployment, and the initial operation of a distributed system for the remote monitoring and operation of multiple heterogeneous commercial buildings across the Internet from a single control center. Such systems can significantly reduce building energy usage. Our system is distinguished by its ability to interface to multiple heterogeneous legacy building Energy Management Control Systems (EMCSs), its use of the Common Object Request Broker Architecture (CORBA) standard communication protocols for the former task, development of a standardized naming system for monitoring points in buildings, the use of a relational OEMS to store and process time series data, automatic time and unit conversion, and a scripted time series visualization system. We describe our design choices and our experiences in development and operation. We note requirements for future distributed systems software for interoperability of heterogeneous real-time data acquisition and control systems. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Olken, F (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Mailstop 50B-3238,1 Cyclotron Rd, Berkeley, CA 94720 USA. EM olken@lbl.gov; jacobsen@wiwi.hu-berlin.de NR 35 TC 1 Z9 1 U1 1 U2 2 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 2 PENN PLAZA, STE 701, NEW YORK, NY 10121-0701 USA SN 0362-1340 J9 ACM SIGPLAN NOTICES JI ACM Sigplan Not. PD OCT PY 1998 VL 33 IS 10 BP 284 EP 295 DI 10.1145/286942.286968 PG 12 WC Computer Science, Software Engineering SC Computer Science GA 127YK UT WOS:000076378100025 ER PT J AU Forslund, D Barry, T Vines, D Raj, R Tiwary, A AF Forslund, D Barry, T Vines, D Raj, R Tiwary, A TI Building distributed systems SO ACM SIGPLAN NOTICES LA English DT Editorial Material C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. LinkSoft Corp, Chicago, IL USA. Boeing Co, Informat & Support Serv, Res & Technol Grp, Seattle, WA 98124 USA. Univ Washington, Dept Comp Sci, Seattle, WA 98195 USA. SUNY Coll Oswego, Oswego, NY 13126 USA. RP Forslund, D (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 USA SN 0362-1340 J9 ACM SIGPLAN NOTICES JI ACM Sigplan Not. PD OCT PY 1998 VL 33 IS 10 BP 412 EP 416 PG 5 WC Computer Science, Software Engineering SC Computer Science GA 127YK UT WOS:000076378100034 ER PT J AU Kolda, TG O'Leary, DP AF Kolda, TG O'Leary, DP TI A semidiscrete matrix decomposition for latent semantic indexing in information retrieval SO ACM TRANSACTIONS ON INFORMATION SYSTEMS LA English DT Article DE algorithms; data mining; latent semantic indexing; semidiscrete decomposition; singular-value decomposition; text retrieval AB The vast amount of textual information available today is useless unless it can be effectively and efficiently searched. The goal in information retrieval is to find documents that are relevant to a given user query. We can represent a document collection by a matrix whose (i, j) entry is nonzero only if the ith term appears in the jth document; thus each document corresponds to a column vector. The query is also represented as a column vector whose ith term is nonzero only if the ith term appears in the query. We score each document for relevancy by taking its inner product with the query. The highest-scoring documents are considered the most relevant. Unfortunately, this method does not necessarily retrieve all relevant documents because it is based on literal term matching. Latent semantic indexing (LSI) replaces the document matrix with an approximation generated by the truncated singular-value decomposition (SVD). This method has been shown to overcome many difficulties associated with literal term matching. In this article we propose replacing the SVD with the semidiscrete decomposition (SDD). We will describe the SDD approximation, show how to compute it, and compare the SDD-based LSI method to the SVD-bascd LSI method. We will show that SDD-based LSI does as well as SVD-based LSI in terms of document retrieval while requiring only one-twentieth the storage and one-half the time to compute each query. We will also show how to update the SDD approximation when documents are added or deleted from the document collection. C1 Oak Ridge Natl Lab, Math Sci Sect, Oak Ridge, TN 37831 USA. Univ Maryland, Dept Comp Sci, College Pk, MD 20742 USA. Univ Maryland, Inst Adv Comp Studies, College Pk, MD 20742 USA. RP Kolda, TG (reprint author), Oak Ridge Natl Lab, Math Sci Sect, POB 2008,Bldg 6012, Oak Ridge, TN 37831 USA. RI Kolda, Tamara/B-1628-2009 OI Kolda, Tamara/0000-0003-4176-2493 NR 23 TC 83 Z9 86 U1 0 U2 6 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 USA SN 1046-8188 J9 ACM T INFORM SYST JI ACM Trans. Inf. Syst. PD OCT PY 1998 VL 16 IS 4 BP 322 EP 346 DI 10.1145/291128.291131 PG 25 WC Computer Science, Information Systems SC Computer Science GA 164YQ UT WOS:000078491500002 ER PT J AU Dawson, S Dittmaier, S Spira, M AF Dawson, S Dittmaier, S Spira, M TI Two-loop QCD corrections to Higgs-pair production at the LHC SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT Zeuthen Workshop on Elementary Particle Theory - Loops and Legs in Gauge Theories CY APR 19-24, 1998 CL RHEINSBERG, GERMANY SP DESY Zeuthen AB The calculation of the next-to-leading order QCD corrections to the production of a neutral Higgs-boson pair is briefly summarized. The dominant production mechanism is gluon fusion via top-quark loops, so that the QCD corrections can be considered, to good approximation, in the limit of a heavy top-quark mass. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. CERN, Div Theory, CH-1211 Geneva 23, Switzerland. Univ Hamburg, Inst Theoret Phys 2, D-22761 Hamburg, Germany. RP Dawson, S (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD OCT PY 1998 VL 29 IS 10 BP 2875 EP 2882 PG 8 WC Physics, Multidisciplinary SC Physics GA 127BX UT WOS:000076331600033 ER PT J AU Romig, AD AF Romig, AD TI How to get (and stay) connected SO ADVANCED MATERIALS & PROCESSES LA English DT Editorial Material C1 Sandia Natl Labs, Microsyst Sci Technol & Components, Livermore, CA 94550 USA. RP Romig, AD (reprint author), Sandia Natl Labs, Microsyst Sci Technol & Components, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 0026-0665 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD OCT PY 1998 VL 154 IS 4 BP 3 EP 3 PG 1 WC Materials Science, Multidisciplinary SC Materials Science GA 126TG UT WOS:000076309300001 ER PT J AU Percus, AG Martin, OC AF Percus, AG Martin, OC TI Scaling universalities of kth-nearest neighbor distances on closed manifolds SO ADVANCES IN APPLIED MATHEMATICS LA English DT Article DE stochastic geometry; nearest neighbors AB Take N sites distributed randomly and uniformly on a smooth closed surface. We express the expected distance [D-k(N)] from an arbitrary point on the surface to its kth-nearest neighboring site, in terms of the function A(l) giving the area of a disc of radius I about that point. We then find two universalities. First, for a flat surface, where A(I)= pi/(2). [D-k(N)] is separable in k and N. All kth-nearest neighbor distances thus scale the same way in N;. Second, for a curved surface, [D-k(N)] averaged over the surface is a topological invariant at leading and subleading order in a large N expansion. The 1/N scaling series then depends, up through O(1/N), only on the surface's topology and not on its precise shape. Pie discuss the case of higher dimensions (d > 2), and also interpret our results using Regge calculus. (C) 1998 Academic Press. C1 Univ Calif Los Alamos Natl Lab, CIC 3, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ Paris Sud, Inst Phys Nucl, Div Phys Theor, F-91406 Orsay, France. RP Percus, AG (reprint author), Univ Calif Los Alamos Natl Lab, CIC 3, POB 1663,MS-B258, Los Alamos, NM 87545 USA. RI Martin, Olivier/B-6656-2012 OI Martin, Olivier/0000-0002-5295-5963 NR 10 TC 16 Z9 16 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0196-8858 J9 ADV APPL MATH JI Adv. Appl. Math. PD OCT PY 1998 VL 21 IS 3 BP 424 EP 436 DI 10.1006/aama.1998.0607 PG 13 WC Mathematics, Applied SC Mathematics GA 122EB UT WOS:000076058000004 ER PT J AU Keller, JM French, JD Dinger, B McDonough, M Gold, B Cloutier, C Carinci, L Van Horn, E Ewsuk, K Blumenthal, W AF Keller, JM French, JD Dinger, B McDonough, M Gold, B Cloutier, C Carinci, L Van Horn, E Ewsuk, K Blumenthal, W TI Industry, government team to improve ceramic manufacturing SO AMERICAN CERAMIC SOCIETY BULLETIN LA English DT Article AB Five competing companies, acting as a consortium, and two national laboratories are working together to develop highly advanced manufacturing technology. C1 Delphi Energy & Engine Management Syst, Flint, MI USA. Adv Cerametr, Lambertville, NJ USA. CeremTec, Laurens, SC USA. Super Tech Ceram, St Albans, VT USA. Zircoa Inc, Solon, OH USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Keller, JM (reprint author), Delphi Energy & Engine Management Syst, Flint, MI USA. NR 0 TC 14 Z9 14 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7812 J9 AM CERAM SOC BULL JI Am. Ceram. Soc. Bull. PD OCT PY 1998 VL 77 IS 10 BP 52 EP 57 PG 6 WC Materials Science, Ceramics SC Materials Science GA 128TE UT WOS:000076421800005 ER PT J AU Jones, DW Gordon, AH AF Jones, DW Gordon, AH TI State and economy in ancient Egypt: Fiscal vocabulary of the New Kingdom SO AMERICAN JOURNAL OF ARCHAEOLOGY LA English DT Book Review C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Archaeologia, Oakland, CA 94610 USA. RP Jones, DW (reprint author), Oak Ridge Natl Lab, Bldg 4500N,MS-6205, Oak Ridge, TN 37831 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ARCHAEOLOGICAL INST PI NEW YORK PA 135 WILLIAM ST, NEW YORK, NY 10038-3805 USA SN 0002-9114 J9 AM J ARCHAEOL JI Am. J. Archaeol. PD OCT PY 1998 VL 102 IS 4 BP 850 EP 851 DI 10.2307/506127 PG 2 WC Archaeology SC Archaeology GA 132MK UT WOS:000076633700053 ER PT J AU Stapp, HP AF Stapp, HP TI Meaning of counterfactual statements in quantum physics SO AMERICAN JOURNAL OF PHYSICS LA English DT Article AB David Mermin suggests that my recent proof pertaining to quantum nonlocality is undermined by an essential ambiguity pertaining to the meaning of counterfactual statements in quantum physics. The ambiguity he cites arises from his imposition of a certain criterion for the meaningfulness of such counterfactual statements. That criterion conflates the meaning of a counterfactual statement with the details of a proof of its validity in such a way as to make the meaning of such a statement dependent upon the context in which it occurs. That dependence violates the normal demand in logic that the meaning of a statement be defined by the words in the statement itself, not by the context in which the statement occurs. My proof conforms to that normal requirement. I describe the context-independent meaning within my proof of the counterfactual statements in question. (C) 1998 American Association of Physics Teachers. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Stapp, HP (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 3 TC 20 Z9 20 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD OCT PY 1998 VL 66 IS 10 BP 924 EP 926 DI 10.1119/1.18989 PG 3 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 125JM UT WOS:000076234500017 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Gatley, SJ Logan, J Ding, YS Hitzemann, R Pappas, N AF Volkow, ND Wang, GJ Fowler, JS Gatley, SJ Logan, J Ding, YS Hitzemann, R Pappas, N TI Dopamine transporter occupancies in the human brain induced by therapeutic doses of oral methylphenidate SO AMERICAN JOURNAL OF PSYCHIATRY LA English DT Article ID DEFICIT-HYPERACTIVITY DISORDER; DL-THREO-METHYLPHENIDATE; POSITRON EMISSION TOMOGRAPHY; INTRAVENOUS METHYLPHENIDATE; C-11 RACLOPRIDE; ABUSE LIABILITY; COCAINE; BINDING; PHARMACOKINETICS; PET AB Objective: The therapeutic effects of methylphenidate in the treatment of attention deficit disorder have been attributed to its ability to increase the synaptic concentration of dopamine by blocking the dopamine transporters. However, the levels of dopamine transporter blockade achieved by therapeutic doses of methylphenidate are not known. This study measured, for the first time, dopamine transporter occupancy by orally administered methylphenidate in the human brain and its rate of uptake in the brain. Method: Positron emission tomography (PET) and [C-11]cocaine were used to estimate dopamine transporter occupancies after different doses of oral methylphenidate in seven normal subjects (mean age=24 years, SD=7). In addition, the pharmacokinetics of oral methylphenidate were measured in the baboon brain through use of PET and [C-11]methylphenidate administered through an orogastric tube. Results: At 120 minutes after administration, oral methylphenidate produced a dose-dependent blockade of dopamine transporter; means=12% (SD= 4%) for 5 mg, 40% (SD=12%) for 10 mg, 54% (SD=5%) for 20 mg, 72% (SD=3%) for 40 mg, and 74% (SD=2%) for 60 mg. The estimated dose of oral methylphenidate required to block 50% of the dopamine transporter corresponded to 0.25 mg/kg. Oral methylphenidate did not reach peak concentration in brain until 60 minutes after its administration. Conclusions: Oral methylphenidate is very effective in blocking dopamine transporters, and at the weight-adjusted doses used therapeutically (0.3 to 0.6 mg/kg), it is likely to occupy more than 50% of the dopamine transporters. The time to reach peak brain uptake for oral methylphenidate in brain corresponds well with the reported time course to reach peak behavioral effects. 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. FU NIDA NIH HHS [DA-09490] NR 37 TC 431 Z9 439 U1 7 U2 24 PU AMER PSYCHIATRIC ASSOCIATION PI WASHINGTON PA 1400 K ST NW, WASHINGTON, DC 20005 USA SN 0002-953X J9 AM J PSYCHIAT JI Am. J. Psychiat. PD OCT PY 1998 VL 155 IS 10 BP 1325 EP 1331 PG 7 WC Psychiatry SC Psychiatry GA 125HY UT WOS:000076233200005 PM 9766762 ER PT J AU Shalliker, RA Broyles, BS Guiochon, G AF Shalliker, RA Broyles, BS Guiochon, G TI What the eye does not see does not bother the mind SO AMERICAN LABORATORY LA English DT Article ID CHROMATOGRAPHY; SAMPLE AB An investigation of the broadening of bands in chromatographic columns is reported in this article. The conclusions will suggest possible remedies to problems met by bench chromatographers. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Analyt Sci Div, Oak Ridge, TN USA. RP Shalliker, RA (reprint author), Univ Tennessee, Dept Chem, 1420 Circle Dr, Knoxville, TN 37996 USA. NR 19 TC 11 Z9 12 U1 1 U2 1 PU INT SCIENTIFIC COMMUN INC PI SHELTON PA PO BOX 870, 30 CONTROLS DRIVE, SHELTON, CT 06484-0870 USA SN 0044-7749 J9 AM LAB JI Am. Lab. PD OCT PY 1998 VL 30 IS 21 BP 124 EP + PG 7 WC Chemistry, Analytical; Instruments & Instrumentation SC Chemistry; Instruments & Instrumentation GA 138JZ UT WOS:000076969900016 ER PT J AU Gavin, IM Melnik, SM Yurina, NP Khabarova, MI Bavykin, SG AF Gavin, IM Melnik, SM Yurina, NP Khabarova, MI Bavykin, SG TI Zero-length protein-nucleic acid crosslinking by radical-generating coordination complexes as a probe for analysis of protein-DNA interactions in vitro and in vivo SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID NICOTIANA-TABACUM-L; CROSS-LINKING; BINDING PROTEINS; SPINACH-CHLOROPLASTS; CHEMICAL NUCLEASES; CHROMATIN; BLEOMYCIN; NUCLEOIDS; IDENTIFICATION; REPLICATION AB Redox-active coordination complexes such as 1,10-phenanthroline-Cu(II) (OP-Cu) and bleomycin-Fe(III) are commonly used as "chemical nucleases" to introduce single-strand breaks in nucleic acids. Here we report that under certain conditions these complexes may crosslink proteins to nucleic acids. In vitro experiments suggest that proteins are crosslinked to DNA by a mechanism similar to dimethyl sulfate-induced crosslinking. Furthermore, we demonstrate that the OP-Cu complex can generate protein-DNA crosslinks in mammalian cells in vivo. By combining the OP-Cu crosslinking and a "protein shadow" hybridization assay we identify proteins interacting with DNA in isolated pea chloroplasts and show that this methodology can be applied to detect DNA-binding proteins on specific DNA sequences either in vitro or in vivo. (C) 1998 Academic Press. C1 Russian Acad Sci, WA Engelhardt Inst Mol Biol, Moscow 117984, Russia. Russian Acad Sci, AN Bach Inst Biochem, Moscow 117071, Russia. Russian Acad Sci, Inst Theoret & Expt Biophys, Pushchino 142292, Russia. RP Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, 9700 S Cass Ave,Bldg 202, Argonne, IL 60439 USA. EM sbavykin@everest.bim.anl.gov NR 31 TC 15 Z9 15 U1 1 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-2697 EI 1096-0309 J9 ANAL BIOCHEM JI Anal. Biochem. PD OCT 1 PY 1998 VL 263 IS 1 BP 26 EP 30 DI 10.1006/abio.1998.2827 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 127RC UT WOS:000076363500004 PM 9750138 ER PT J AU Tan, HD Yeung, ES AF Tan, HD Yeung, ES TI Automation and integration of multiplexed on-line sample preparation with capillary electrophoresis for high-throughput DNA sequencing SO ANALYTICAL CHEMISTRY LA English DT Article ID ASSISTED LASER-DESORPTION; SINGLE-MOLECULE DETECTION; FLIGHT MASS-SPECTROMETRY; ARRAY ELECTROPHORESIS; GEL-ELECTROPHORESIS; HIGH-SPEED; FLUORESCENCE DETECTION; DEVICE; HYBRIDIZATION; SYSTEM AB An integrated and multiplexed on-line instrument starting from DNA templates to their primary sequences has been demonstrated based on multiplexed microfluidics and capillary array electrophoresis. The instrument automatically processes eight templates through reaction, purification, denaturation, preconcentration, injection, separation, and detection in a parallel fashion. A multiplexed freeze/thaw switching principle and a distribution network were utilized to manage flow and sample transportation. Dye-labeled terminator cycle-sequencing reactions are performed in an eight-capillary array in a hot-air thermal cycler. Subsequently, the sequencing ladders are directly loaded into separate size exclusion chromatographic columns operated at similar to 60 degrees C for purification. On-line denaturation and stacking injection for capillary electrophoresis is simultaneously accomplished at a cross assembly set at similar to 70 degrees C. Not only the separation capillary array but also the reaction capillary array and purification columns can be regenerated after every run. The raw data allow base calling up to 460 bp with an accuracy of 98%. The system is scalable to a 96-capillary array and will benefit not only high-speed, high-throughput DNA sequencing but also genetic typing. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. FU NHGRI NIH HHS [HG-01385] NR 53 TC 56 Z9 56 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD OCT 1 PY 1998 VL 70 IS 19 BP 4044 EP 4053 DI 10.1021/ac980406i PG 10 WC Chemistry, Analytical SC Chemistry GA 125GD UT WOS:000076228300016 PM 9784747 ER PT J AU Shaffer, SA Prior, DC Anderson, GA Udseth, HR Smith, RD AF Shaffer, SA Prior, DC Anderson, GA Udseth, HR Smith, RD TI An ion funnel interface for improved ion focusing and sensitivity using electrospray ionization mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID ATTOMOLE; CAPILLARIES; PRINCIPLES; TRANSPORT; LEVEL; GUIDE AB To improve upon the already impressive sensitivity achievable with electrospray ionization sources, a novel electrohydrodynamic ion funnel interface has been developed and implemented with a triple-quadrupole mass spectrometer. The ion funnel interface effectively consists of a series of ring electrodes of increasingly small internal diameters to which rf and de electric potentials are coapplied. In the 1-10-Torr pressure range, the electric fields cause the collisionally damped ions to be more effectively focused and transmitted as a collimated ion beam. This paper describes the ion funnel design and presents an evaluation of its performance using a triple-quadrupole mass spectrometer. Ion transmission and m/z discriminating parameters (resulting in both effective low- and high-m/z cutoffs) are presented based upon both ion current measurements and mass spectra. Electrospray ionization mass spectra of selected protein solutions demonstrated well over 1 order of magnitude increase in signal relative to that of the instrument operated in its standard (inlet capillary-skimmer) configuration under similar conditions. The present results suggest that it will be feasible to realize close to 100% ion transmission efficiency for analytically relevant ions through the electrospray ionization interface and into the mass analyzer. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Shaffer, Scott/F-8650-2010; Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 28 TC 167 Z9 171 U1 9 U2 78 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 EI 1520-6882 J9 ANAL CHEM JI Anal. Chem. PD OCT 1 PY 1998 VL 70 IS 19 BP 4111 EP 4119 DI 10.1021/ac9802170 PG 9 WC Chemistry, Analytical SC Chemistry GA 125GD UT WOS:000076228300026 PM 9784749 ER PT J AU Beylkin, G Brewster, ME Gilbert, AC AF Beylkin, G Brewster, ME Gilbert, AC TI A multiresolution method for numerical reduction and homogenization of nonlinear ODEs SO APPLIED AND COMPUTATIONAL HARMONIC ANALYSIS LA English DT Article AB The multiresolution analysis (MRA) strategy for the reduction of a nonlinear differential equation is a procedure for constructing an equation directly for the coarse scale component of the solution. The MRA homogenization process is a method for building a simpler equation whose solution has the same coarse behavior as the solution to a more complex equation. We present two multiresolution reduction methods for nonlinear differential equations: a numerical procedure and an analytic method. We also discuss one possible appproach to the homogenization method, (C) 1998 Academic Press. C1 Univ Colorado, Program Appl Math, Boulder, CO 80309 USA. Pacific NW Lab, Richland, WA 99352 USA. Princeton Univ, Dept Math, Princeton, NJ 08544 USA. RP Beylkin, G (reprint author), Univ Colorado, Program Appl Math, Boulder, CO 80309 USA. RI Athan, Tara/C-8633-2009; Beylkin, Gregory/G-6653-2011; OI BEYLKIN, GREGORY/0000-0003-3447-1460 NR 18 TC 4 Z9 4 U1 0 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1063-5203 J9 APPL COMPUT HARMON A JI Appl. Comput. Harmon. Anal. PD OCT PY 1998 VL 5 IS 4 BP 450 EP 486 DI 10.1006/acha.1998.0250 PG 37 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 127WC UT WOS:000076372700004 ER PT J AU Phillips, DA Sande, ES Vriezen, JAC de Bruijn, FJ Le Rudulier, D Joseph, CM AF Phillips, DA Sande, ES Vriezen, JAC de Bruijn, FJ Le Rudulier, D Joseph, CM TI A new genetic locus in Sinorhizobium meliloti is involved in stachydrine utilization SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID RHIZOBIUM-MELILOTI; RHIZOSPHERE BACTERIA; ESCHERICHIA-COLI; PROLINE BETAINE; MUTANTS; CATABOLISM; CLONING; PUTA; LEGUMINOSARUM; CONSTRUCTION AB Stachydrine, a betaine released by germinating alfalfa seeds, functions as an inducer of nodulation genes, a catabolite, and an osmoprotectant in Sinorhizobium meliloti. Two stachydrine-inducible genes were found in S. muliloti 1021 by mutation with a Tn5-luxAB promoter probe. Both mutant strains (S10 and S11) formed effective alfalfa root nodules, but neither grew on stachydrine as the sole carbon and nitrogen source. When grown in the absence or presence of salt stress, S10 and S11 took up [C-14]stachydrine as well as wild-type cells did, but neither used stachydrine effectively as an osmoprotectant. In the absence of salt stress, both S10 and S11 took up less [C-14]proline than wild-type cells did. S10 and S11 appeared to colonize alfalfa roots normally in single-strain tests, but when mixed with the wild-type strain, their rhizosphere counts were reduced more than 50% (P less than or equal to 0.01) relative to the wild type. These results suggest that stachydrine catabolism contributes to root colonization. DNA sequence analysis identified the mutated locus in S11 as putA, and the luxAB fusion in that gene was induced by proline as web as stachydrine. DNA that restored the capacity of mutant S10 to catabolize stachydrine contained a new open reading frame, stcD. All data are consistent with the concept that stcD codes for ari enzyme that produces proline by demethylation of N-methylproline, a degradation product of stachydrine. C1 Univ Calif Davis, Dept Agron & Range Sci, Livermore, CA 95616 USA. Michigan State Univ, Dept Microbiol, E Lansing, MI 48824 USA. Michigan State Univ, Plant Res Lab, US DOE, E Lansing, MI 48824 USA. Univ Nice, CNRS, URA 1114, Lab Biol Vegetale & Microbiol, F-06108 Nice 2, France. RP Joseph, CM (reprint author), Univ Calif Davis, Dept Agron & Range Sci, Livermore, CA 95616 USA. EM CMJoseph@UCDavis.edu NR 48 TC 39 Z9 42 U1 2 U2 4 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD OCT PY 1998 VL 64 IS 10 BP 3954 EP 3960 PG 7 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 126LP UT WOS:000076295100060 ER PT J AU Small, W Celliers, PM Da Silva, LB Matthews, DL Soltz, BA AF Small, W Celliers, PM Da Silva, LB Matthews, DL Soltz, BA TI Two-color mid-infrared thermometer with a hollow glass optical fiber SO APPLIED OPTICS LA English DT Article ID WAVE-GUIDES; TEMPERATURE-MEASUREMENTS; RADIOMETRY; TRANSMISSION AB We have developed a low-temperature optical-fiber-based two-color infrared thermometer. A single 700-mu m-bore hollow glass optical fiber collects and transmits radiation that is then modulated and split into two paths by a reflective optical chopper. Two different thermoelectrically cooled mid-infrared HgCdZnTe photoconductors monitor the chopped signals that are recovered with lock-in amplification. With the two previously obtained blackbody calibration equations, a computer algorithm calculates the true temperature and emissivity of a target in real time, taking into account reflection of the ambient radiation field from the target surface. The small numerical aperture of the hollow glass fiber and the fast response of the detectors, together with the two-color principle, permit high spatial and temporal resolution while allowing the user to dynamically alter the fiber-to-target distance. (C) 1998 Optical Society of America. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Convers Energy Enterprises, Spring Valley, NY 10977 USA. RP Small, W (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-399, Livermore, CA 94550 USA. NR 10 TC 10 Z9 10 U1 1 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD OCT 1 PY 1998 VL 37 IS 28 BP 6677 EP 6683 DI 10.1364/AO.37.006677 PG 7 WC Optics SC Optics GA 125ZC UT WOS:000076266800014 PM 18301477 ER PT J AU Nadig, SG Lee, KL Adams, SM AF Nadig, SG Lee, KL Adams, SM TI Evaluating alterations of genetic diversity in sunfish populations exposed to contaminants using RAPD assay SO AQUATIC TOXICOLOGY LA English DT Article DE genetic diversity; contaminants; fish populations; RAPD assay ID PRONE ATLANTIC TOMCOD; ALLOZYME GENOTYPES; MERCURY POLLUTION; INORGANIC MERCURY; MITOCHONDRIAL-DNA; ARBITRARY PRIMERS; FISH; SELECTION; MOSQUITOFISH; POLYMORPHISM AB Bioindicators of pollutant exposure can be more sensitive and ecologically relevant than simply measuring levels of pollutants in the environment and are applied here as a tool for assessing environmental stress on aquatic organisms. DNA polymorphisms, detected by using the randomly amplified polymorphic DNA (RAPD) technique, are used as biomarkers to assess genetic diversity and genetic distance among populations of redbreast sunfish (Lepomis auritus) residing in reference streams and a contaminated stream (East Fork Poplar Creek, EFPC). The RAPD technique uses the polymerase chain reaction (PCR) with short oligonucleotide primers under reduced stringency to produce DNA fragments which, when analyzed by gel electrophoresis, form banding patterns similar to DNA fingerprints. A total of 13 primers were used which produced 45 polymorphic bands among all populations of fish tested. Using this technique, only slight differences in genetic diversity were detected among populations of sunfish within EFPC although the diversity of all EFPC populations analyzed together did differ from the reference populations. Fish populations in EFPC were consistently less genetically distant from each other than they were from each of the reference sites. Differences in genetic distance between populations may be due to selection pressure of pollutants on fsh in EFPC which is supported by the finding that frequencies of certain unique genotypes in EFPC sunfish were correlated with the downstream pollutant gradient. These results are discussed in relation to implications of RAPD assays and recent remediation efforts within EFPC. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Adams, SM (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 58 TC 38 Z9 47 U1 3 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-445X J9 AQUAT TOXICOL JI Aquat. Toxicol. PD OCT PY 1998 VL 43 IS 2-3 BP 163 EP 178 DI 10.1016/S0166-445X(98)00049-6 PG 16 WC Marine & Freshwater Biology; Toxicology SC Marine & Freshwater Biology; Toxicology GA 153LE UT WOS:000077833900007 ER PT J AU Leeper, DA Taylor, BE AF Leeper, DA Taylor, BE TI Abundance, biomass and production of aquatic invertebrates in Rainbow Bay, a temporary wetland in South Carolina, USA SO ARCHIV FUR HYDROBIOLOGIE LA English DT Article ID FRESH-WATER MARSH; SECONDARY PRODUCTION; COMMUNITY STRUCTURE; BLACKWATER RIVER; RAPID GROWTH; CHIRONOMIDAE; ZOOPLANKTON; PREDATION; HABITATS; DYNAMICS AB The abundance, biomass and production of aquatic invertebrates were determined for 1992 and 1993 at Rainbow Bay, a small (maximum inundated area similar to 1.5 ha), shallow (maximum depth similar to 1 m) depression wetland in South Carolina, USA, which dries annually. Estimates were based on invertebrates collected from benthic substrates and the water column, including those associated with macrophytes. Mean invertebrate density during the Periods of inundation was 7.1x10(5) animals/m(2) in 1992 and 7.7x10(5) animals/m(2) in 1993. Small taxa, including nematodes, rotifers and microcrustaceans dominated numerically. Biomass was 2.1 g dry mass/m(2) in 1992, and 0.9 g/m(2) in 1993. Oligochaetes, insects (mostly chironomids) and crustaceans dominated the biomass. The lower biomass in 1993 was the result of significant reductions in the biomass of oligochaetes and benthic chironomids. Laboratory-derived daily growth rates of oligochaetes and chironomids collected from Rainbow Bay, along with daily production rates for crustaceans and rotifers derived from other studies were used to estimate secondary production. Production in 1993 (14.7 g dry mass/m(2)) was less than in 1992 (36.7 g/m(2)), due primarily to lower biomass of oligochaetes and chironomids in 1993. Differences between years in abundance, biomass and production were associated with differences in hydrology of the wetland, including duration of inundation, and abundances of salamanders. C1 Sw Florida Water Management Dist, Brooksville, FL 34609 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Leeper, DA (reprint author), Sw Florida Water Management Dist, 2379 Broad St, Brooksville, FL 34609 USA. NR 62 TC 39 Z9 39 U1 5 U2 11 PU E SCHWEIZERBART'SCHE VERLAGS PI STUTTGART PA NAEGELE U OBERMILLER JOHANNESSTRASSE 3A, D 70176 STUTTGART, GERMANY SN 0003-9136 J9 ARCH HYDROBIOL JI Arch. Hydrobiol. PD OCT PY 1998 VL 143 IS 3 BP 335 EP 362 PG 28 WC Limnology; Marine & Freshwater Biology SC Marine & Freshwater Biology GA 143NB UT WOS:000077260800005 ER PT J AU Brambley, M Pratt, R Chassin, D Katipamula, S Hatley, D AF Brambley, M Pratt, R Chassin, D Katipamula, S Hatley, D TI Diagnostics for outdoor air ventilation and economizers SO ASHRAE JOURNAL-AMERICAN SOCIETY OF HEATING REFRIGERATING AND AIR-CONDITIONING ENGINEERS LA English DT Article ID FAULT-DETECTION; SYSTEMS; MODELS C1 Pacific NW Lab, Richland, WA 99352 USA. RP Brambley, M (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 11 TC 13 Z9 13 U1 0 U2 1 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.-Am. Soc. Heat Refrig. Air-Cond. Eng. PD OCT PY 1998 VL 40 IS 10 BP 49 EP + PG 5 WC Thermodynamics; Construction & Building Technology; Engineering, Mechanical SC Thermodynamics; Construction & Building Technology; Engineering GA 130HL UT WOS:000076514100013 ER PT J AU Guhathakurta, P Webster, ZT Yanny, B Schneider, DP Bahcall, JN AF Guhathakurta, P Webster, ZT Yanny, B Schneider, DP Bahcall, JN TI Globular cluster photometry with the Hubble Space Telescope. VII. Color gradients and blue stragglers in the central region of M30 from Wide Field Planetary Camera 2 observations SO ASTRONOMICAL JOURNAL LA English DT Article DE blue stragglers; color-magnitude diagrams; globular clusters : individual (M30,; NGC 7099); stars : evolution; stars : luminosity function, mass function ID MASS SEGREGATION; POPULATION GRADIENTS; LUMINOSITY FUNCTIONS; STELLAR POPULATIONS; CORE; GALAXY; WFPC2; PERFORMANCE; SYSTEM; STARS AB We present F555W (V), F439W (B), and F336W (U) photometry of 9507 stars in the central 2' of the dense, post-core-collapse cluster M30 (NGC 7099) derived from Hubble Space Telescope Wide Field Planetary Camera 2 images. These data are used to study the mix of stellar populations in the central region of the cluster. Forty-eight blue straggler stars are identified; they are found to be strongly concentrated toward the cluster center. The specific frequency of blue stragglers, F-BSS = N(BSS)/N(V < T-HB + 2), is 0.25 +/- 0.05 in the inner region of M30 (r < 20 "), significantly higher than the frequency found in other clusters: F-BSS = 0.05-0.15. The shape of M30's blue straggler luminosity function resembles the prediction of the collisional formation model, and is inconsistent with the binary merger model of Bailyn & Pinsonneault. An unusually blue star (B = 18.6, B-V = -0.97), possibly a cataclysmic variable based on its color, is found about 1." 2 from the crowded cluster center; the photometric uncertainty for this star is large, however, because of the presence of a very close neighbor. Bright red giant stars (B < 16.6) appear to be depleted by a factor of 2-3 In the inner r < 10 " relative to fainter giants, subgiants, and main-sequence turnoff stars (95% significance). We confirm that there is a radial gradient in the color of the overall cluster light, going from B-V similar to 0.82 at r similar to 1' to B-V similar to 0.45 in the central 10 ". The central depletion of the bright red giants is responsible for about half of the observed color gradient; the rest of the gradient is caused by the relative underabundance of faint red main-sequence stars near the cluster center (presumably a result of mass segregation). The luminosity function of M30's evolved stars does not match the luminosity function shape derived from standard stellar evolutionary models: the ratio of the number of bright giants to the number of turnoff stars in the cluster is 30% higher than predicted by the model (3.8 sigma effect), roughly independent of red giant brightness over the range M-V = -2 to +2. C1 Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Inst Adv Study, Sch Nat Sci, Princeton, NJ 08540 USA. RP Guhathakurta, P (reprint author), Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Dept Astron & Astrophys, 1156 High St, Santa Cruz, CA 95064 USA. NR 59 TC 30 Z9 30 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 1998 VL 116 IS 4 BP 1757 EP 1774 DI 10.1086/300566 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 128NP UT WOS:000076413100022 ER PT J AU Platania, P Bensadoun, M Bersanelli, M De Amici, G Kogut, A Levin, S Maino, D Smoot, GF AF Platania, P Bensadoun, M Bersanelli, M De Amici, G Kogut, A Levin, S Maino, D Smoot, GF TI A determination of the spectral index of galactic synchrotron emission in the 1-10 GHz range SO ASTROPHYSICAL JOURNAL LA English DT Article DE diffuse radiation; radiation mechanisms : nonthermal ID DIFFERENTIAL MICROWAVE RADIOMETER; COSMIC BACKGROUND-RADIATION; CONTINUUM EMISSION; TEMPERATURE; FLUCTUATIONS; FREQUENCY; SKY; MHZ AB We present an analysis of simultaneous multifrequency measurements of the Galactic emission in the 1-10 GHz range with 18 degrees angular resolution taken from a high-altitude site. Our data yield a determination of the synchrotron spectral index between 1.4 and 7.5 GHz of beta(syn) = 2.81 +/- 0.16. Combining our data with maps made by Haslam et al. and Reich & Reich, we find beta(syn) = 2.76 +/- 0.11 in the 0.4-7.5 GHz range. These results are in agreement with the few previously published measurements. The variation of beta(syn) with frequency based on our results and compared with other data found in the literature suggests a steepening of the synchrotron spectrum toward high frequencies, as expected from theory because of the steepening of the parent cosmic-ray electron energy spectrum. Comparison between the Haslam data and the 19 GHz map of Cottingham also indicates a spatial variation of the spectral index on large angular scales. Additional high-quality data are necessary to provide a serious study of these effects. C1 CNR, Ist Fis Cosm, I-20133 Milan, Italy. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. TRW Co Inc, Space & Technol Div, Redondo Beach, CA 90278 USA. NASA, Goddard Space Flight Ctr, Hughes STX, Greenbelt, MD 20771 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. SISSA, Sch Adv Int Studies, I-34014 Trieste, Italy. RP Platania, P (reprint author), CNR, Ist Fis Cosm, Via Bassini 15, I-20133 Milan, Italy. RI Kogut, Alan/D-6293-2012 NR 27 TC 85 Z9 85 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP 473 EP 483 DI 10.1086/306175 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500001 ER PT J AU Mauche, CW Raymond, JC AF Mauche, CW Raymond, JC TI ORFEUS II far-ultraviolet spectroscopy of AM Herculis SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; stars : individual (AM Herculis); stars : magnetic fields; ultraviolet : stars; white dwarfs ID X-RAY; WHITE-DWARF; IUE; ACCRETION AB Six high-resolution (lambda/Delta lambda approximate to 3000) far-UV (lambda lambda = 910-1210 Angstrom) spectra of the magnetic cataclysmic variable AM Herculis were acquired in 1996 November during the flight of the ORFEUS-SPAS II mission. AM Her was in a high optical state at the time of the observations, and the spectra reveal emission lines of O VI lambda lambda 1032, 1038, C III lambda lambda 977, 1176, and He II lambda 1085 superposed on a nearly flat continuum. Continuum flux variations can be described as per Gansicke et al. by a approximate to 20 kK white dwarf with a approximate to 37 kK hot spot covering a fraction f similar to 0.15 of the surface of the white dwarf, but we caution that the expected Lyman absorption lines are not detected. The O VI emission lines have a broad and narrow component structure similar to that of the optical emission lines, the C III and He II emission lines are dominated by the broad component, and the radial velocities of these lines are consistent with an origin of the narrow and broad components in the irradiated face of the secondary and the accretion funnel, respectively. The density of the narrow- and broad-line regions is n(nlr) similar to 3 x 10(10) cm(-3) and n(blr) similar to 1 x 10(12) cm(-3) respectively, yet the narrow-line region is optically thick in the O VI line and the broad-line region is optically thin; apparently, the velocity shear in the broad-line region allows the O VI photons to escape, rendering the gas effectively optically thin. The orbital phase variations of the emission-line fluxes are unexplained. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Mauche, CW (reprint author), Lawrence Livermore Natl Lab, L-41,POB 808, Livermore, CA 94550 USA. EM mauche@cygnus.llnl.gov; jraymond@cfa.harvard.edu NR 31 TC 15 Z9 15 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 1998 VL 505 IS 2 BP 869 EP 875 DI 10.1086/306185 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LF UT WOS:000077778500030 ER PT J AU Kapahi, VK Athreya, RM van Breugel, W McCarthy, PJ Subrahmanya, CR AF Kapahi, VK Athreya, RM van Breugel, W McCarthy, PJ Subrahmanya, CR TI The Molonglo Reference Catalog 1 Jy radio source survey. II. Radio structures of galaxy identifications SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE galaxies, structure; radio continuum, galaxies; surveys ID HIGH-REDSHIFT; OPTICAL IDENTIFICATIONS; STAR FORMATION; LUMINOSITY DEPENDENCE; COMPLETE SAMPLE; RICH CLUSTERS; VLA SURVEY; SPECTRUM; ALIGNMENT; QUASARS AB This is the second in a series of papers discussing the radio, optical, and near-IR properties of a large and complete sample of radio sources selected from the Molonglo Reference Catalog (MRC) at 408 MHz. The sample consists of 557 radio sources from the MRC that have S(0.408)greater than or equal to 0.95 Jy, -30 degrees < delta < -20 degrees, and \b\ greater than or equal to 20 degrees but excluding the right ascension range of 14(h)03(m)-20(h)20(m). While 111 of these are identified with quasars (including six with BL Lac objects), a vast majority of the rest are identified with galaxies. Only a small fraction (less than or similar to 2%) appear to have no optical or near-IR counterparts down to an r magnitude of similar to 24 or a K magnitude of similar to 19. A similar fraction have ambiguous identifications. This paper presents the radio structures of the 446 radio sources in the sample that are either identified with galaxies or that have remained unidentified. Most of the structural information given in the paper is based on high-resolution (similar to 1 "-10 ") observations made with the Very Large Array at a frequency of 4.86 GHz. Several of the large or diffuse sources were also observed at 1.41 GHz. Contour plots of the radio images are also presented for the well-resolved sources. A substantial fraction (similar to 20%) of the sources in the galaxy sample is found to be of the "compact steep spectrum" variety with alpha(0.408)(4.86) > 0.5 and linear size l less than or similar to 20 kpc (for H-0 = 50 km s(-1) Mpc(-1); q(0) = 0.5). C1 TIFR, Natl Ctr Radio Astrophys, Pune 411007, Maharashtra, India. LLNL, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. RP Kapahi, VK (reprint author), TIFR, Natl Ctr Radio Astrophys, Pune Univ Campus, Pune 411007, Maharashtra, India. RI Subramanya, C/D-4898-2012; Astronomy & Astrophysics Group, Raman Res Institute/D-4046-2012 NR 63 TC 40 Z9 40 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD OCT PY 1998 VL 118 IS 2 BP 275 EP 326 DI 10.1086/313144 PG 52 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 130JQ UT WOS:000076517300002 ER PT J AU Kapahi, VK Athreya, RM Subrahmanya, CR Baker, JC Hunstead, RW McCarthy, PJ van Breugel, W AF Kapahi, VK Athreya, RM Subrahmanya, CR Baker, JC Hunstead, RW McCarthy, PJ van Breugel, W TI The Molonglo Reference Catalog 1 Jy radio source survey. III. Identification of a complete quasar sample SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE galaxies, structure; quasars, general; radio continuum, galaxies; surveys ID SOUTHERN SKY; GALAXIES; REDSHIFTS; POSITIONS; EMISSION; OBJECTS AB We present a new complete sample of 111 radio quasars (including six BL Lac objects) selected from the Molonglo Reference Catalog (MRC) at 408 MHz. The sample, which we call the Molonglo Quasar Sample (MQS), forms part of a complete survey of 557 MRC radio sources with S(408) greater than or equal to 0.95 Jy in the declination range -30 degrees < delta < -20 degrees, b > 20 degrees but excluding the R.A. range 14(h)03(m)-20(h)20(m). Quasar classifications are based on high-resolution radio images, deep optical identifications, and follow-up spectroscopy of sources in the strip. The relatively low radio frequency of the finding survey and the complete optical identification of quasars to faint magnitudes ensure that the MQS is relatively free from orientation biases that affect most other samples of radio-loud quasars. The MQS is therefore particularly well suited to investigating the effects of radio axis orientation on quasar properties. This paper describes in detail the formation of the MQS and presents basic radio and optical data, including VLA images of extended radio sources in the sample and a complete set of optical finding charts. C1 TIFR, Natl Ctr Radio Astrophys, Pune 411007, Maharashtra, India. Univ Sydney, Sch Phys, Sydney, NSW 2006, Australia. Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. LLNL, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. RP Kapahi, VK (reprint author), TIFR, Natl Ctr Radio Astrophys, Pune Univ Campus, Pune 411007, Maharashtra, India. EM vijay@ncra.tifr.res.in; ramana@ncra.tifr.res.in; crs@ncra.tifr.res.in; jcb@mrao.cam.ac.uk; RWH@astrop.physics.usyd.edu.au; pmc2@ocwi.edu; wil@sunlight.llnl.gov RI Subramanya, C/D-4898-2012; Astronomy & Astrophysics Group, Raman Res Institute/D-4046-2012 NR 43 TC 50 Z9 50 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD OCT PY 1998 VL 118 IS 2 BP 327 EP 352 DI 10.1086/313145 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 130JQ UT WOS:000076517300003 ER PT J AU Laros, JG Hurley, KC Fenimore, EE Klebesadel, RW Briggs, MS Kouveliotou, C McCollough, ML Fishman, GJ Meegan, CA Cline, TL Boer, M Niel, M AF Laros, JG Hurley, KC Fenimore, EE Klebesadel, RW Briggs, MS Kouveliotou, C McCollough, ML Fishman, GJ Meegan, CA Cline, TL Boer, M Niel, M TI Gamma-ray burst arrival time localizations: Simultaneous observations by Pioneer Venus Orbiter, Compton Gamma-Ray Observatory, and Ulysses SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE gamma rays, bursts; methods, observational ID RADIO AB Between the Compton Gamma Ray Observatory (CGRO) launch in 1991 April and the Pioneer Venus Orbiter (PVO) demise in 1992 October, concurrent coverage by CGRO, PVO, and Ulysses was obtained for several hundred gamma-ray bursts (GRBs). Although most of these were below the PVO and UIysses thresholds, 37 were positively detected by all three spacecraft, with data quality adequate for quantitative localization analysis. All were localized independently to similar to 2 degrees accuracy by the CGRO Burst and Transient Source Experiment (BATSE), and three were also localized by COMPTEL. we computed arrival-time error boxes, whose larger dimensions range from about 2' to several degrees and whose smaller dimensions are in the arcminute range. Twelve have areas less than 10 arcmin(2), and only four have areas greater than 1 deg(2). The area of the smallest box is 0.44 arcmin(2). We find that the overall BATSE localization accuracy for these events is consistent with the most recent stated uncertainties. This work indicates that the ROSAT soft X-ray source found within a preliminary IPN error box for GB920501 (Trig 1576) (Hurley et al.) is less likely to be the GRB counterpart than previously reported. C1 Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Alabama, Huntsville, AL 35899 USA. NASA, George C Marshall Space Flight Ctr, USRA, Huntsville, AL 35812 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Ctr Etud Spatiale Rayonnements, F-31029 Toulouse, France. RP Laros, JG (reprint author), Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. OI Boer, Michel/0000-0001-9157-4349 NR 18 TC 19 Z9 19 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD OCT PY 1998 VL 118 IS 2 BP 391 EP 399 DI 10.1086/313139 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 130JQ UT WOS:000076517300005 ER PT J AU Khanna, S Atalay, M Lodge, JK Laaksonen, DE Roy, S Hanninen, O Packer, L Sen, CK AF Khanna, S Atalay, M Lodge, JK Laaksonen, DE Roy, S Hanninen, O Packer, L Sen, CK TI Skeletal muscle and liver lipoyllysine content in response to exercise, training and dietary alpha-lipoic acid supplementation SO BIOCHEMISTRY AND MOLECULAR BIOLOGY INTERNATIONAL LA English DT Article DE thioctic acid; antioxidant; mitochondria; thiols; redox; nutrition ID PYRUVATE-DEHYDROGENASE COMPLEX; GLYCINE CLEAVAGE SYSTEM; MITOCHONDRIAL-FUNCTION; METABOLIC ANTIOXIDANT; H-PROTEIN; NEUROPATHY; RATS; ACYLTRANSFERASES; TRANSCRIPTION; GLUTATHIONE AB In human cells, alpha-lipoic acid (LA) is present in a bound lipoyllysine form in mitochondrial proteins that play a central role in oxidative metabolism. The possible effects of oral LA supplementation, a single bout of strenuous exercise and endurance exercise training on the lipoyllysine content in skeletal muscle and liver tissues of rat were examined. Incorporation of lipoyl moiety to tissue protein was not increased by enhanced abundance of LA in the diet. Endurance exercise training markedly increased lipoyllysine content in the liver at rest. A bout of exhaustive exercise also increased hepatic lipoyllysine content. A significant interaction of exhaustive exercise and training to increase tissue lipoyllysine content was evident. In vastus lateralis skeletal muscle, training did not influence tissue lipoyllysine content. A single bout of exhaustive exercise, however, clearly increased the level of lipoyllysine in the muscle. Comparison of tissue lipoyllysine data with that of free or loosely-bound LA results showed a clear lack of association between the two apparently related parameters. Tightly protein-bound lipoyllysine pool in tissues appeared to be independent of the loosely-bound or free LA status in the tissue. C1 Univ Kuopio, Dept Physiol, FIN-70211 Kuopio, Finland. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, EETD, Berkeley, CA 94720 USA. RP Sen, CK (reprint author), Univ Kuopio, Dept Physiol, FIN-70211 Kuopio, Finland. RI Sen, Chandan/A-8762-2013; Khanna, Savita/E-3378-2011; Roy, sashwati/E-3990-2011 FU NIDDK NIH HHS [DK 50430]; NIGMS NIH HHS [GM27345] NR 53 TC 10 Z9 10 U1 1 U2 3 PU ACADEMIC PRESS AUST PI MARRICKVILLE PA LOCKED BAG 16, MARRICKVILLE, NSW 2204, AUSTRALIA SN 1039-9712 J9 BIOCHEM MOL BIOL INT JI Biochem. Mol. Biol. Int. PD OCT PY 1998 VL 46 IS 2 BP 297 EP 306 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 133DW UT WOS:000076672000010 PM 9801798 ER PT J AU Stagg, K Spicer, LJ Sreenan, JM Roche, JF Diskin, MG AF Stagg, K Spicer, LJ Sreenan, JM Roche, JF Diskin, MG TI Effect of calf isolation on follicular wave dynamics, gonadotropin and metabolic hormone changes, and interval to first ovulation in beef cows fed either of two energy levels postpartum SO BIOLOGY OF REPRODUCTION LA English DT Article ID GROWTH-FACTOR-I; SUCKLING-MEDIATED INHIBITION; FACTOR BINDING-PROTEINS; LUTEINIZING-HORMONE; BODY CONDITION; STIMULATING-HORMONE; DIETARY ENERGY; IGF-I; PREPUBERTAL HEIFERS; ANESTROUS PERIOD AB The effects of postpartum energy intake, restricted suckling, and cow-calf isolation on concentrations of LH, FSH, growth hormone, and insulin-like growth factor-I (IGF-I) and on postpartum anestrous interval were determined by randomly allocating beef cows with a mean body condition score of 2.3 +/- 0.1 to receive either 80 MJ metabolizable energy (low-energy diet [L]; n = 51) or 120 MJ metabolizable energy (high-energy diet [H]; n = 52) per cow per day from calving. At 30 days postpartum, cows within diet were randomized to 1) have continued full access to their calves from birth to weaning (ad libitum suckling: ADLIB), 2) be suckled once-daily with their calves penned adjacent (restricted suckling, adjacent: RESADJ), 3) be isolated from all calves except for a once-daily suckling period (restricted suckling, isolated: RESISO). The mean postpartum interval was similar (p > 0.10) for L and H cows (62 and 63 days, respectively). RESADJ cows had a shorter (p < 0.05) postpartum interval than ADLIB cows, and RESISO cows had a shorter interval tp < 0.05) than RESADJ cows, with all effects independent (p > 0.10) of diet. FSH secretion pattern was not affected by diet, suckling treatment, sequential follicle wave number, or follicle wave retrospectively realigned to emergence of first ovulatory wave. Within 5 days of suckling restriction and calf isolation, the number of LH pulses increased from 0.18 to 0.48 pulses per hour (p < 0.05). Both mean LH and the mean number of LH pulses increased linearly (p < 0.01) during the six follicle waves up to the first ovulatory wave. From 80 days before, until the time of, first ovulation, growth hormone decreased tp < 0.05) while IGF-I increased (p < 0.05), irrespective of treatment. The results indicate that the "suckling effect" in beef cows is the major factor affecting the duration of the postpartum interval and suggests that the maternal bond is more important than suckling in regulating LH pulse frequency, the key endocrine factor determining whether or not a dominant follicles ovulates. Removal of the suckling effect resulted in a rapid increase in LH pulse frequency, which was not dependent on level of postpartum nutrition, at least within the nutritional limits of this study. Mean concentrations of FSH, unlike LH, did not vary with follicle wave number, suggesting that lack of FSH is not a major factor delaying the resumption of ovulation in postpartum beef cows. C1 Agr & Food Dev Author, TEAGASC, Athenry Res Ctr, Athenry, Galway, Ireland. Natl Univ Ireland Univ Coll Dublin, Fac Vet Med, Dublin 4, Ireland. Oklahoma State Univ, Dept Anim Sci, Stillwater, OK 74078 USA. RP Diskin, MG (reprint author), Agr & Food Dev Author, TEAGASC, Athenry Res Ctr, Athenry, Galway, Ireland. EM mdi@belclare.teagasc.ie NR 57 TC 104 Z9 111 U1 0 U2 20 PU SOC STUDY REPRODUCTION PI MADISON PA 1603 MONROE ST, MADISON, WI 53711-2021 USA SN 0006-3363 J9 BIOL REPROD JI Biol. Reprod. PD OCT PY 1998 VL 59 IS 4 BP 777 EP 783 DI 10.1095/biolreprod59.4.777 PG 7 WC Reproductive Biology SC Reproductive Biology GA 124NF UT WOS:000076188100008 PM 9746725 ER PT J AU Wagner, J Li, YX Pearson, J Keizer, J AF Wagner, J Li, YX Pearson, J Keizer, J TI Simulation of the fertilization Ca2+ wave in Xenopus laevis eggs SO BIOPHYSICAL JOURNAL LA English DT Article ID CORTICAL ENDOPLASMIC-RETICULUM; INOSITOL 1,4,5-TRISPHOSPHATE; CALCIUM OSCILLATIONS; OOCYTES; TRISPHOSPHATE; RELEASE; ACTIVATION; DIFFUSION; MODEL; CA-2+ AB In the preceding paper Fontanilla and Nuccitelli (Biophysical Journal 75:2079-2087(1998)) present detailed measurements of the shape and speed of the fertilization Ca2+ wave in Xenopus laevis eggs. In order to help interpret their results, we develop here a computational technique based on the finite element method that allows us to carry out realistic simulations of the fertilization wave. Our simulations support the hypothesis that-the physiological state of the mature egg is bistable, i.e., that its cytoplasm can accommodate two alternative physiological Ca2+ concentrations: a low concentration characteristic of the prefertilization state and a greatly elevated concentration characteristic of the state following the passage; of the wave. We explore this hypothesis by assuming that the bistability is due to the release and re-uptake properties of the endoplasmic reticulum (ER) as determined by inositol trisphosphate (IP3) receptor/Ca2+ channels and sarcoendoplasmic reticulum calcium ATPase (SERCA) pumps. When combined with buffered diffusion of Ca2+ in the cytoplasm, our simulations show that inhomogeneities in the Ca2+ release properties near the plasma membrane are required tb explain the temporal and spatial dependences of the shape and speed of these waves. Our results are consistent with an elevated IP3 concentration near the plasma membrane in the unfertilized egg that is augmented significantly near the site of fertilization. These gradients are essential in determining the concave shape of the Ca2+ fertilization wave front. C1 Univ Calif Davis, Inst Theoret Dynam, Sect Neurobiol Physiol & Behav, Davis, CA 95616 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Univ Calif Davis, Inst Theoret Dynam, Sect Neurobiol Physiol & Behav, Davis, CA 95616 USA. EM jekeizer@ucdavis.edu FU NCRR NIH HHS [RR10081] NR 45 TC 48 Z9 49 U1 0 U2 1 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 EI 1542-0086 J9 BIOPHYS J JI Biophys. J. PD OCT PY 1998 VL 75 IS 4 BP 2088 EP 2097 PG 10 WC Biophysics SC Biophysics GA 123UT UT WOS:000076144000049 PM 9746551 ER PT J AU Osmond, CB Daley, PF Badger, MR Luttge, U AF Osmond, CB Daley, PF Badger, MR Luttge, U TI Chlorophyll fluorescence quenching during photosynthetic induction in leaves of Abutilon striatum Dicks. Infected with Abutilon mosaic virus, observed with a field-portable imaging system SO BOTANICA ACTA LA English DT Article DE Abutilon strictum; chlorophyll fluorescence imaging; nonphotochemical quenching; virus infection; Abutilon mosaic virus ID PLANT STRESS; LEAF PHOTOSYNTHESIS; GLECHOMA-HEDERACEA; ULTRASTRUCTURE; TRANSMISSION; OSCILLATIONS; GEMINIVIRUS; PHYSIOLOGY; TOPOGRAPHY; MALVACEAE AB A portable Chl fluorescence imaging system was used to characterise nonuniform Chl fluorescence quenching in Abutilon strictum leaves infected with phloem-localised abutilon mosaic virus. The instrument was used to observe fluorescence emission at intervals during induction transients, and to map nonphotochemical quenching during saturating pulses applied in the course of these transients. Two symptom types were distinguished: yellow vein-associated motifs that showed lower maximum Chl fluorescence than nearby green tissues, but virtually zero nonphotochemical quenching, and vein-defined mosaics (pale green) that initially showed normal maximum Chl fluorescence but strongly impaired nonphotochemical quenching. Mature vein-defined mosaics (yellow to white areas) resembled vein-associated symptoms with zero nonphotochemical quenching. Islands of apparently healthy green tissue enclosed by mosaic symptoms showed slower nonphotochemical quenching than controls. Possible effects of localised carbohydrate accumulation, thought to follow from infection by the phloem-limited virus, on photosynthetic processes as well as the synthesis and stability of chloroplast protein complexes, are discussed in the context of symptom development. C1 Australian Natl Univ, Res Sch Biol Sci, Inst Adv Studies, Photobioenerget Grp, Canberra, ACT 2601, Australia. Australian Natl Univ, Res Sch Biol Sci, Inst Adv Studies, Mol Plant Physiol Grp, Canberra, ACT 2601, Australia. Lawrence Livermore Natl Lab, Environm Restorat Div, Livermore, CA USA. Tech Univ Darmstadt, Inst Bot, Darmstadt, Germany. RP Osmond, CB (reprint author), Australian Natl Univ, Res Sch Biol Sci, Inst Adv Studies, Photobioenerget Grp, Box 475, Canberra, ACT 2601, Australia. RI Badger, Murray/C-8153-2009 NR 36 TC 45 Z9 48 U1 1 U2 4 PU GEORG THIEME VERLAG KG PI STUTTGART PA RUDIGERSTR 14, D-70469 STUTTGART, GERMANY SN 0932-8629 J9 BOT ACTA JI Bot. Acta PD OCT PY 1998 VL 111 IS 5 BP 390 EP 397 PG 8 WC Plant Sciences SC Plant Sciences GA 131DN UT WOS:000076560600007 ER PT J AU Schultz, CA Myers, SC Hipp, J Young, CJ AF Schultz, CA Myers, SC Hipp, J Young, CJ TI Nonstationary Bayesian kriging: A predictive technique to generate spatial corrections for seismic detection, location, and identification SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article AB Seismic characterization works to improve the detection, location, and identification of seismic events by correcting for inaccuracies in geophysical models. These inaccuracies are caused by inherent averaging in the model, and, as a result, exact data values cannot be directly recovered at a point in the model. Seismic characterization involves cataloging reference events so that inaccuracies in the model can be mapped at these points and true data values can be retained through a correction. Application of these corrections to a new event requires the accurate prediction of the correction value at a point that is near but not necessarily coincident with the reference events. Given that these reference events can be sparsely distributed geographically, both interpolation and extrapolation of corrections to the new point are required. In this study, we develop a closed-form representation of Bayesian kriging (linear prediction) that incorporates variable spatial damping. The result is a robust nonstationary algorithm for spatially interpolating geophysical corrections. This algorithm extends local trends when data coverage is good and allows for damping (blending) to an a priori background mean when data coverage is poor. Benchmark tests show that the technique gives reliable predictions of the correction value along with an appropriate uncertainty estimate. Tests with travel-time residual data demonstrate that combining variable damping with an azimuthal coverage criterion reduces the large errors that occur with more classical linear prediction techniques, especially when values are extrapolated in poor coverage regions. In the travel-time correction case, this technique generates both seismic corrections along with uncertainties and can properly incorporate model error in the final location estimate. Results favor the applicability of this nonstationary algorithm to other types of seismic corrections such as amplitude and attenuation measures. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Schultz, CA (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. RI Myers, Stephen/K-1368-2014 OI Myers, Stephen/0000-0002-0315-5599 NR 18 TC 50 Z9 55 U1 0 U2 3 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 OCT PY 1998 VL 88 IS 5 BP 1275 EP 1288 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 134BF UT WOS:000076722400015 ER PT J AU Martin, RR Sham, TK Won, GW van der Heide, P Jones, KW Song, SR Protz, R AF Martin, RR Sham, TK Won, GW van der Heide, P Jones, KW Song, SR Protz, R TI Secondary ion mass spectroscopy and synchrotron X-ray fluorescence in the study of the qualitative variation in metal content with time in tree rings SO CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE LA English DT Article ID POLLUTION AB Secondary ion mass spectroscopy and synchrotron X-ray fluorescence analysis have been used to document the changes in metal content across the ring system of trees from northern Canada. The results show a seasonal qualitative variation in the uptake of Na, Al, K, Ca, Cr, Mn, Fe, Cu, and Zn. Diffusional models show that locally elevated concentrations of selected metals are sufficiently stable within individual rings that variations in content among rings remain at detectable levels for at least a century. C1 Univ Western Ontario, Dept Chem, London, ON N6A 5B7, Canada. Univ Western Ontario, Surface Sci Western, London, ON N6A 5B7, Canada. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Univ Guelph, Dept Land Resource Sci, Guelph, ON N1G 2W1, Canada. RP Martin, RR (reprint author), Univ Western Ontario, Dept Chem, London, ON N6A 5B7, Canada. EM rrhm@julian.uwo.ca OI Song, Sheng-Rong/0000-0001-5428-4318 NR 22 TC 8 Z9 8 U1 0 U2 1 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0045-5067 J9 CAN J FOREST RES JI Can. J. For. Res.-Rev. Can. Rech. For. PD OCT PY 1998 VL 28 IS 10 BP 1464 EP 1470 PG 7 WC Forestry SC Forestry GA 157JH UT WOS:000078057400004 ER PT J AU Chang, GW Terzaghi-Howe, M AF Chang, GW Terzaghi-Howe, M TI Multiple changes in gene expression are associated with normal cell-induced modulation of the neoplastic phenotype SO CANCER RESEARCH LA English DT Article ID INTEGRIN-ASSOCIATED PROTEIN; GUANINE-NUCLEOTIDE EXCHANGE; CYCLASE-ASSOCIATED PROTEIN; DBL ONCOGENE PRODUCT; DIFFERENTIAL DISPLAY; SACCHAROMYCES-CEREVISIAE; ALPHA-CATENIN; EPITHELIAL-CELLS; MESSENGER-RNA; CANCER-CELLS AB Specific regulatory pathways in neoplastic cells seem to be responsive to control signals provided by the normal cell/tissue environment. The present experiments were designed to define, at the molecular level, the growth-regulatory signals in neoplastic cells that are associated with the modulation of expression of the neoplastic phenotype by normal cell populations. When cultured in the presence of normal cell-conditioned medium, a highly malignant rat tracheal carcinoma-derived cell population (IC-12) undergoes dramatic changes in morphology, and the anchorage-independent growth of these cells is inhibited. This phenomenon is termed normalization. The strategy adopted for elucidating the cellular/molecular changes associated with the induction of these phenotypic alterations was to define the differences in mRNA expression patterns between IC-12 populations exhibiting the neoplastic phenotype ( wild-type cells) and those exhibiting the normalized phenotype, For this purpose, the differential display technique and subsequent Northern blot analyses were used, Once specific, differentially expressed genes were identified, the temporal sequence of altered gene expression was determined by monitoring the levels of mRNA expression after the addition of normal cell-conditioned medium. Some of the identified known genes are grouped into three general categories: (a) group I genes are those involved in cellular adhesion processes; (b) group II genes are those involved in signal transduction pathways; and (c) group III genes are those involved in transcriptional and translational processes, Genes that are differentially expressed during the normalization process seemed to exhibit characteristic temporal expression patterns after the addition of normal cell-conditioned medium. Identification of these differentially expressed genes and their associated cellular functions provide insight into some of those regulatory pathways in neoplastic cells that are amenable to regulation by normal cells. An analysis of the temporal sequence of altered gene expression provides further information that allows the identification of those genes that are likely to be critical upstream effecters regulating transcriptional regulatory events that result in the moderation of neoplastic behavior. C1 Univ Tennessee, Oak Ridge Grad Sch Biomed Sci, Oak Ridge, TN 37830 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Terzaghi-Howe, M (reprint author), 5594 County Rd 1, Montrose, CO 81401 USA. FU NCI NIH HHS [CA34695] NR 49 TC 8 Z9 8 U1 0 U2 1 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 OCT 1 PY 1998 VL 58 IS 19 BP 4445 EP 4452 PG 8 WC Oncology SC Oncology GA 125CD UT WOS:000076219100040 PM 9766677 ER PT J AU Hansen, LA Malarkey, DE Wilkinson, JE Rosenberg, M Woychik, RE Tennant, RW AF Hansen, LA Malarkey, DE Wilkinson, JE Rosenberg, M Woychik, RE Tennant, RW TI Effect of the viable-yellow (A(vy)) agouti allele on skin tumorigenesis and humoral hypercalcemia in v-Ha-ras transgenic TG.AC mice SO CARCINOGENESIS LA English DT Article ID MOUSE SKIN; GENE; PROLIFERATION; CARCINOMAS; MUTATION; GROWTH; TUMORS; COLOR AB We previously reported that papillomas can arise from the follicular epithelium of v-Ha-ras transgenic TG.AC mice. Since the viable-yellow mutation (A(vy)) Of the mouse agouti gene which regulates coat color pigmentation by acting within the micro-environment of the hair follicle has been shown to function as a tumor promoter in the liver, we hypothesized that it may also play a role in TG.AC skin tumorigenesis. Endogenous agouti protein product was detected in the outer root sheath of anagen hair follicles following plucking of the hair shaft, but not in the interfollicular epithelium, in TG.AC mice on an FVB/N genetic background. It was also detected in papillomas from these mice produced by 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking. Expression of the A(vy) allele in the v-Ha-ms transgenic TG.AC mouse line results in an similar to 2-fold increase in papilloma development compared with controls which did not carry the A(vy) allele following twice-weekly treatment with 1.25, 2.5 or 5.0 mu g TPA. In addition, TPA-treated, papilloma-bearing F-1 mice which carried the A(vy) allele, but not F-1 mice which did not carry the A(vy) allele, exhibited a syndrome of humoral hypercalcemia mediated by parathyroid hormone-related protein (PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia, Thus, we conclude that the A(vy) allele can influence the development of skin tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic TG.AC mice. C1 NIEHS, Lab Environm Carcinogenesis & Mutagenesis, Res Triangle Pk, NC 27709 USA. NIEHS, Lab Expt Pathol, Res Triangle Pk, NC 27709 USA. Univ Tennessee, Knoxville, TN USA. Glaxo Wellcome Inc, Res Triangle Pk, NC 27709 USA. Oak Ridge Natl Labs, Oak Ridge, TN USA. RP Hansen, LA (reprint author), NCI, Cellular Carcinogenesis & Tumor Promot Lab, Bldg 37,Room 3B17,37 Convent Dr,MSC 4255, Bethesda, MD 20892 USA. NR 22 TC 8 Z9 8 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0143-3334 J9 CARCINOGENESIS JI Carcinogenesis PD OCT PY 1998 VL 19 IS 10 BP 1837 EP 1845 DI 10.1093/carcin/19.10.1837 PG 9 WC Oncology SC Oncology GA 130GL UT WOS:000076511800019 PM 9806167 ER PT J AU Hercod, DJ Brady, PV Gregory, RT AF Hercod, DJ Brady, PV Gregory, RT TI Catchment-scale coupling between pyrite oxidation and calcite weathering SO CHEMICAL GEOLOGY LA English DT Article; Proceedings Paper CT European Research Conference on the Geochemistry of Crustal Fluids CY DEC 06-11, 1996 CL SEEFELD, AUSTRIA DE weathering; pyrite; calcite; sulfate ID ALPINE AB Integrated time series of major element concentrations and flow rates from a small watershed (White Rock Creek, Dallas, TX) are used to examine the general hydrogeochemical controls on calcite weathering and the specific role of trace pyrite oxidation in base cation export. White Rock Creek is a perennial gaining stream occupying a catchment underlain by expanding clay soils, and an uppermost fractured bedrock weathering zone (which acts as a surface aquifer) below which there is low permeability Austin Chalk. Seasonal variations in cation export are controlled predominantly by temperature effects on carbonate solubility, dilution by variable amounts of rainfall, and possibly organic activity. Creek water P-CO2 is 7 to 10 times atmospheric P-CO2 throughout the year, and does not correlate with surface temperature. Non-pyrite sulfate inputs are well-constrained; moreover, integrated runoff and solute export from the basin are similar to global mean values. Pyrite, although present only as a trace component, accounts for a disproportionate amount of bedrock weathering (similar to 40%) when oxidized to produce sulfuric acid. Irreversible dissolution of pyrite is insensitive to seasonal changes in temperature, runoff, and organic activity and probably reflects the slow movement of a weathering front at depth through the aquifer. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Triton Energy, London WC2R 0AP, England. Sandia Natl Labs, Albuquerque, NM 87185 USA. So Methodist Univ, Dept Geol Sci, Dallas, TX 75265 USA. RP Hercod, DJ (reprint author), Triton Energy, Wellington House,125 Strand, London WC2R 0AP, England. NR 25 TC 23 Z9 24 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD OCT 1 PY 1998 VL 151 IS 1-4 BP 259 EP 276 DI 10.1016/S0009-2541(98)00084-9 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 133ZW UT WOS:000076718300020 ER PT J AU Dingley, KH Roberts, ML Velsko, CA Turteltaub, KW AF Dingley, KH Roberts, ML Velsko, CA Turteltaub, KW TI Attomole detection of 3H in biological samples using accelerator mass spectrometry: Application in low-dose, dual-isotope tracer studies in conjunction with C-14 accelerator mass spectrometry SO CHEMICAL RESEARCH IN TOXICOLOGY LA English DT Article ID 5 HETEROCYCLIC AMINES; 2-AMINO-1-METHYL-6-PHENYLIMIDAZO<4,5-B>PYRIDINE PHIP; COVALENT BINDING; FOCI DEVELOPMENT; COOKED FOODS; LIVER DNA; RATS; MEIQX; MICE; CARCINOGENICITY AB This is the first demonstration of the use of accelerator mass spectrometry (AMS) as a tool for the measurement of H-3 With attomole (10(-18) mol) sensitivity in a biological study. AMS is an analytical technique for quantifying rare isotopes with high sensitivity and precision and has been most commonly used to measure C-14 in both the geosciences and more recently in biomedical research. AMS measurement of serially diluted samples containing a H-3-labeled tracer showed a strong correlation with liquid scintillation counting. The mean coefficient of variation of H-3 AMS based upon the analysis of separately prepared aliquots of these samples was 12%. The sensitivity for H-3 detection in tissue, protein, and DNA was approximately 2-4 amol/mg of sample. This high sensitivity is comparable to detection limits for C-14-labeled carcinogens using C-14 AMS and demonstrates the feasibility of H-3 AMS for biomedical studies. One application of this technique is in low-dose, dual-isotope studies in conjunction with C-14 AMS. We measured the levels of H-3-labeled 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and C-14-labeled 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) in rat liver tissue and bound to liver DNA and protein 4.5 h following acute administration of individual or coadministered doses in the range of 4-5100 pmol/kg of body weight. Levels of PhIP and MeIQx in whole tissue and bound to liver protein were dose-dependent. MeIQx-protein and -DNA adduct levels were higher than PhIP adduct levels, which is consistent with their respective carcinogenicity in this organ. Coadministration of PhIP and MeIQx did not demonstrate any measurable synergistic effects compared to administration of these compounds individually. These studies demonstrate the application of AMS for the low-level detection of H-3 in small biological samples and for its use in conjunction with C-14 AMS for dual-labeling studies. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. RP Dingley, KH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. FU NCI NIH HHS [CA55861]; NIEHS NIH HHS [ESO 04705] NR 25 TC 39 Z9 40 U1 0 U2 6 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 OCT PY 1998 VL 11 IS 10 BP 1217 EP 1222 DI 10.1021/tx9801458 PG 6 WC Chemistry, Medicinal; Chemistry, Multidisciplinary; Toxicology SC Pharmacology & Pharmacy; Chemistry; Toxicology GA 132QX UT WOS:000076642000013 PM 9778319 ER PT J AU Corbett, JD Garcia, E Guloy, AM Hurng, WM Kwon, YU Leon-Escamilla, EA AF Corbett, JD Garcia, E Guloy, AM Hurng, WM Kwon, YU Leon-Escamilla, EA TI Widespread interstitial chemistry of Mn5Si3-Type and related phases. Hidden impurities and opportunities SO CHEMISTRY OF MATERIALS LA English DT Review ID POLAR INTERMETALLIC COMPOUNDS; ZINTL PHASE; SYSTEM; METALS; STABILIZATION; EARTH; TIN; DERIVATIVES; HYDROGEN; ZR5SB3 AB The many A(5)B(3) phases that exhibit hexagonal Mn5Si3-type structures by and large have a nearly unique abilities to bind diverse heteratoms Z in a preformed cavity within a chain of confacial trigonal antiprisms of A. The historical development of this chemistry as interstitially stabilized Nowotny phases and recent research to clarify the necessity for Z and the range of Z possible in certain hosts are described. Some hosts may bind as many as 20 different interstitial Z. Structures, stoichiometric relationships, volume effects, electronic guidelines, anomalies, Nowotny phases that require Z for stability, and a few band calculations are described. The special cases of hosts composed of divalent cations with pnictogens (As-Bi) and tetrels (Si-Pb) and their reactions with H and F are considered. The former Mn5Si3-type phase Lake up some H, but many convert at higher H or F concentrations to the orthorhombic Ca5Sb3F-type (formerly beta-Yb5Sb3) structure. Many of the nominally valence-precise tetrelides with Cr5B3 (or other) structures react with H or F to give the new stuffed Cr5B3 versions with Z in a tetrahedral cavity (a Ca5Sn3F or La5Pb3O type). Some early results demonstrate that highly significant reduction of high-temperature corrosion rates of Ti5Si3 can be secured for Ti(5)Si(3)Z, Z = C or O. The number of uninvestigated Mn5Si3-type host-interstitial Z systems and the unknown ways in which various Z affect; chemical and physical properties in each system are very large. C1 Iowa State Univ Sci & Technol, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Corbett, JD (reprint author), Iowa State Univ Sci & Technol, US DOE, Ames Lab, Ames, IA 50011 USA. NR 65 TC 67 Z9 67 U1 0 U2 12 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 OCT PY 1998 VL 10 IS 10 BP 2824 EP 2836 DI 10.1021/cm980223c PG 13 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 132YF UT WOS:000076658700027 ER PT J AU Nenoff, TM Thoma, SG Provencio, P Maxwell, RS AF Nenoff, TM Thoma, SG Provencio, P Maxwell, RS TI Novel zinc phosphate phases formed with chiral d-glucosamine molecules SO CHEMISTRY OF MATERIALS LA English DT Article ID ZEOLITE; ZINCOPHOSPHATE; SIEVES; FRAMEWORKS AB Chiral syntheses and separations of both intermediate and final compounds are currently extremely important areas of research, especially for the chemical, pharmaceutical, agrochemical, and biomedical industries. We are investigating the synthesis of new inorganic porous materials for enantiomeric selectivity. We present a study of inorganic zinc phosphate crystalline phases templated with the chiral molecule d-glucosamine hydrochloride. The crystallization of these phases is highly dependent on reaction time, temperature, and stoichiometry. Resultant new phases include a mesoporous phase and a layered phase. Data indicates that the walls of the new 32 Angstrom sized mesoporous phase are crystalline and ordered. Characterization techniques applied include powder X-ray diffraction, TEM, and P-31 MAS NMR. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Nenoff, TM (reprint author), Sandia Natl Labs, POB 5800,MS-0710, Albuquerque, NM 87185 USA. NR 28 TC 25 Z9 26 U1 1 U2 9 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 OCT PY 1998 VL 10 IS 10 BP 3077 EP 3080 DI 10.1021/cm980191t PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 132YF UT WOS:000076658700050 ER PT J AU Park, JH Woodward, PM Parise, JB AF Park, JH Woodward, PM Parise, JB TI Predictive modeling and high-pressure - High-temperature synthesis of perovskites containing monovalent silver SO CHEMISTRY OF MATERIALS LA English DT Article ID CRYSTAL-STRUCTURE; LAYERED PEROVSKITE; IONIC-CONDUCTIVITY; OXIDE; DISORDER AB The program POTATO, which was developed to model distorted perovskite structures, has been used to assess the stability of hypothetical compositions and guide the synthesis of new materials at high pressures and high temperatures. The initial result of this effort is the synthesis of two new perovskites, Ca2NdAgTi4O12 and NdAgTi2O6, which were synthesized at 14-14.5 GPa and 1000 degrees C using the uniaxial split sphere anvil type press (USSA-2000). Both compounds are perovskites distorted from the ideal cubic structure by octahedral tilting distortions. Ca2NdAgTi4O12 contains a random distribution of Ca2+/Nd3+/Ag+ ions on the A-site, whereas NdAgTi2O6 has a partially ordered distribution of Nd3+/Ag+ ions. Ca2NdAgTi4O12 adopts the GdFeO3 structure (Glazer tilt system b(-)a(+)b(-)), space group Pnma, with a = 5.44883(4), b = 7.68915(6), and c = 5.42290(3) Angstrom. NdAgTi2O6 belongs to the tetragonal space group P4/nbm, with a 5.45337(3) and c = 7.72934(6) Angstrom. This structure can be derived from the simple cubic perovskite structure by rotations of the octahedra about the c-axis (Glazer tilt system a(0)a(0)c(-)) and partial ordering of Nd3+ and Ag+ ions into alternating layers, perpendicular to the c-axis. C1 SUNY Stony Brook, Dept Chem, Ctr High Pressure Res, Stony Brook, NY 11794 USA. SUNY Stony Brook, Dept Chem, Dept Geosci, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Parise, JB (reprint author), SUNY Stony Brook, Dept Chem, Ctr High Pressure Res, Stony Brook, NY 11794 USA. NR 54 TC 24 Z9 24 U1 0 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD OCT PY 1998 VL 10 IS 10 BP 3092 EP 3100 DI 10.1021/cm980212j PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 132YF UT WOS:000076658700052 ER PT J AU Elder, SH Gao, Y Li, X Liu, J McCready, DE Windisch, CF AF Elder, SH Gao, Y Li, X Liu, J McCready, DE Windisch, CF TI Zirconia-stabilized 25-angstrom TiO2 anatase crystallites in a mesoporous structure SO CHEMISTRY OF MATERIALS LA English DT Article ID HIGH-SURFACE-AREA; MOLECULAR-SIEVES; SEMICONDUCTOR CRYSTALLITES; PORE-SIZE; OXIDE; PARTICLES; MECHANISM; ORGANIZATION; CLUSTERS; METAL AB We have prepared and characterized a mesoporous material where the framework, of both the as-synthesized and calcined materials, is composed of ZrO2-doped 25-Angstrom TiO2 anatase crystallites. The nanocrystalline framework is structured about a surfactant-templated, disordered porous network with a uniform pore diameter of 28 Angstrom. Air calcination at 450 degrees C removes the surfactant to yield a mesoporous solid with surface area of 330 m(2)/g. The mesoporous framework and TiO2 crystallite size are surprisingly robust, and we observed no substantial structural differences between precalcined and calcined products. C1 Pacific NW Lab, Dept Chem & Mat Sci, Richland, WA 99352 USA. Pacific NW Lab, Dept Interfacial & Proc Sci, Richland, WA 99352 USA. RP Elder, SH (reprint author), Pacific NW Lab, Dept Chem & Mat Sci, Richland, WA 99352 USA. NR 51 TC 58 Z9 59 U1 1 U2 6 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 OCT PY 1998 VL 10 IS 10 BP 3140 EP 3145 DI 10.1021/cm980237i PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 132YF UT WOS:000076658700057 ER PT J AU Lehman, R AF Lehman, R TI Research and nonproliferation: A role for private industry SO CHEMTECH LA English DT Editorial Material C1 Univ Calif Lawrence Livermore Natl Lab, Dept Energy, Livermore, CA 94550 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0009-2703 J9 CHEMTECH JI Chemtech PD OCT PY 1998 VL 28 IS 10 BP 14 EP 15 PG 2 WC Chemistry, Applied SC Chemistry GA 128FM UT WOS:000076395100006 ER PT J AU Gates, WP Jaunet, AM Tessier, D Cole, MA Wilkinson, HT Stucki, JW AF Gates, WP Jaunet, AM Tessier, D Cole, MA Wilkinson, HT Stucki, JW TI Swelling and texture of iron-bearing smectites reduced by bacteria SO CLAYS AND CLAY MINERALS LA English DT Article DE bacteria; biological reduction; organo-clay interactions; smectites; structural iron; swelling pressure; texture ID OXIDATION-STATE; STRUCTURAL IRON; REDUCTION; NONTRONITE; MONTMORILLONITE; POLYSACCHARIDE; ADSORPTION; CHARGE AB Microbial reduction of clay mineral structural Fe(III) decreases the swelling of nontronite gels, most importantly at intermediate oxidation states (40 to 80 cmol Fe(II) kg(-1) clay). The purpose of this study was to establish whether microbial reduction of structural Fe(III) decreased the swelling of other Fe-bearing smectites and to discern the influence that organic compounds of microbial origin (bacterial cells, cell fragments and/or exudates) may have on clay swelling and texture. Structural Fe(III) was reduced by incubating smectite suspensions with either a combination of Pseudomonas bacteria or a mixture of anaerobic bacteria. The influence of organics on clay swelling was estimated on smectites suspended in either organic or inorganic media in the absence of bacteria. The gravimetric water content of the reduced clay gels equilibrated at various applied pressures was recorded as a function of Fe oxidation state. Transmission electron microscopy (TEM) was employed to determine the influence of bacteria and type of media on the texture of reduced smectite gels. Reduction of structural Fe(III) by bacteria decreased the swelling pressure of all Fe-bearing smectites. Increased clay swelling, due to the presence of organics (organic medium, exudates or cell fragments), was correlated to the total Fe content, the extent of structural Fe reduction, as well as the initial swelling characteristics of the Fe-bearing smectites. High structural Fe(II) contents (>50 cmol Fe(II) kg(-1)) resulted in increased attractive forces between clay platelets that decreased clay swelling, even in organic medium suspensions. Microbial reduction resulted in increased face-face association of individual clay layers, forming larger and more distinct crystallite subunits than in nonreduced clay gels. But, perhaps more importantly, microbial reduction of structural Fe(III) resulted in an increased association between crystallite subunits and, thus, an overall larger particle size and pore size distribution, due to the interaction of bacteria cells, cell fragments and organic exudates. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. INRA, F-78026 Versailles, France. Univ Illinois, Dept Nat Resources & Environm Sci, Urbana, IL 61801 USA. RP Gates, WP (reprint author), Univ Georgia, Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 29 TC 50 Z9 53 U1 0 U2 13 PU CLAY MINERALS SOCIETY PI BOULDER PA PO BOX 4416, BOULDER, CO 80306 USA SN 0009-8604 J9 CLAY CLAY MINER JI Clay Clay Min. PD OCT PY 1998 VL 46 IS 5 BP 487 EP 497 DI 10.1346/CCMN.1998.0460502 PG 11 WC Chemistry, Physical; Geosciences, Multidisciplinary; Mineralogy; Soil Science SC Chemistry; Geology; Mineralogy; Agriculture GA 143VX UT WOS:000077278800002 ER PT J AU Wigley, TML Jaumann, PJ Santer, BD Taylor, KE AF Wigley, TML Jaumann, PJ Santer, BD Taylor, KE TI Relative detectability of greenhouse-gas and aerosol climate change signals SO CLIMATE DYNAMICS LA English DT Article ID MODEL; ATMOSPHERE AB The use of pattern correlations to compare observed temperature changes with predicted anthropogenic effects has greatly increased our confidence in the reality of these effects. Here we use synthetic observed data to determine the expected behavior of the pattern correlation statistic, R(t), and hence clarify some results obtained in previous studies. We show that, for the specific case considered here (near-surface temperature changes), even with a perfectly-known signal, expected values of R(t) currently should be only of order 0.3-0.5, as observed; that R(t) may show markedly non-linear variations in time; that the CO2-alone signal pattern should be difficult to detect today primarily because of data coverage deficiencies; and why the signal due to combined CO2-aerosol forcing is easier to detect than either the CO2-alone or aerosol-alone signals. Finally, we show that little is to be gained at present by searching for a time-dependent signal compared with a representative constant signal pattern. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diagnosis & Intercomparison, Livermore, CA 94550 USA. RP Wigley, TML (reprint author), Natl Ctr Atmospher Res, Pob 3000, Boulder, CO 80307 USA. RI Wigley, Tom/B-4705-2008; Taylor, Karl/F-7290-2011; Santer, Benjamin/F-9781-2011 OI Taylor, Karl/0000-0002-6491-2135; NR 26 TC 19 Z9 19 U1 1 U2 6 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD OCT PY 1998 VL 14 IS 11 BP 781 EP 790 DI 10.1007/s003820050254 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 129GE UT WOS:000076454800002 ER PT J AU Belgrader, P Benett, W Hadley, D Long, G Mariella, R Milanovich, F Nasarabadi, S Nelson, W Richards, J Stratton, P AF Belgrader, P Benett, W Hadley, D Long, G Mariella, R Milanovich, F Nasarabadi, S Nelson, W Richards, J Stratton, P TI Rapid pathogen detection using a microchip PCR array Instrument SO CLINICAL CHEMISTRY LA English DT Article ID POLYMERASE CHAIN-REACTION; INFECTIOUS-DISEASES; DNA-POLYMERASE; AMPLIFICATION; EMERGENCE AB An array of PCR microchips for rapid, parallel testing of samples for pathogenic microbes is described. The instrument, called the Advanced Nucleic Acid Analyzer (ANAA), utilizes 10 silicon reaction chambers with thin-film resistive heaters and solid-state optics. Features of the system include efficient heating and realtime monitoring, low power requirements for battery operation, and no moving parts for reliability and ruggedness. We analyzed cultures of Erwinia herbicola vegetative cells, Bacillus subtilis spores, and MS2 virions, which simulated pathogenic microbes such as Yersinia pestis, Bacillus anthracis spores, and Venezuelan equine encephalitis, respectively. Detection of microbes was achieved in as little as 16 min with detection limits of 10(5)-10(7) organisms/L (10(2)-10(4) organisms/mL). C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. USN, Med Res Inst, Bethesda, MD 20814 USA. RP Belgrader, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808,L-452, Livermore, CA 94551 USA. EM belgrader1@llnl.gov NR 19 TC 110 Z9 116 U1 0 U2 5 PU AMER ASSOC CLINICAL CHEMISTRY PI WASHINGTON PA 2101 L STREET NW, SUITE 202, WASHINGTON, DC 20037-1526 USA SN 0009-9147 J9 CLIN CHEM JI Clin. Chem. PD OCT PY 1998 VL 44 IS 10 BP 2191 EP 2194 PG 4 WC Medical Laboratory Technology SC Medical Laboratory Technology GA 124RT UT WOS:000076196200020 PM 9761255 ER PT J AU Glarborg, P Alzueta, MU Dam-Johansen, K Miller, JA AF Glarborg, P Alzueta, MU Dam-Johansen, K Miller, JA TI Kinetic modeling of hydrocarbon nitric oxide interactions in a flow reactor SO COMBUSTION AND FLAME LA English DT Review ID KETENYL RADICALS HCCO+NO; PRODUCT BRANCHING RATIOS; ABSOLUTE RATE CONSTANTS; SHOCK-TUBE; DATA-BASE; ETHANE OXIDATION; LASER-ABSORPTION; NATURAL-GAS; DIODE-LASER; TEMPERATURE-DEPENDENCE AB The reduction of nitric oxide by reaction with C-1 and C-2 hydrocarbons under reducing conditions in a flow reactor has been analyzed in terms of a detailed chemical kinetic model. The experimental data were partly adopted from previous work and partly obtained in the present study; they cover the temperature range 800-1500 K and the reburn fuels CH4, C2H2, C2H4, C2H6, and natural gas. Modeling predictions indicate that, under the conditions investigated, HCCO + NO and CH3 + NO are the reactions most important in reducing NO. The HCCO + NO reaction is the dominant reaction when using natural gas or C-2 hydrocarbons as reburn fuels. This reaction leads partly to HCNO, which is recycled to NO, and partly to HCN, which is converted to N-2 or NO. When methane or natural gas are used as reburn fuel, the CH3 + NO reaction contributes significantly to remove NO. Modeling predictions are in reasonably good agreement with the experimental observations for the fuels investigated, even though the NO reduction potential is overpredicted for methane and underpredicted for ethane. Modeling predictions for NO are very sensitive to the formation of HCCO and to the product branching ratio for the HCCO + NO reaction. Furthermore, the present analysis indicates that more work is needed on critical steps in the hydrocarbon oxidation scheme. (C) 1998 by The Combustion Institute. C1 Tech Univ Denmark, Dept Chem Engn, DK-2800 Lyngby, Denmark. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Glarborg, P (reprint author), Tech Univ Denmark, Dept Chem Engn, DK-2800 Lyngby, Denmark. RI Alzueta, Maria U./G-5582-2015 OI Alzueta, Maria U./0000-0003-4679-5761 NR 140 TC 321 Z9 339 U1 4 U2 38 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD OCT PY 1998 VL 115 IS 1-2 BP 1 EP 27 DI 10.1016/S0010-2180(97)00359-3 PG 27 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA ZU524 UT WOS:000074206700001 ER PT J AU Bunimovich, LA Rehacek, J AF Bunimovich, LA Rehacek, J TI How high-dimensional stadia look like SO COMMUNICATIONS IN MATHEMATICAL PHYSICS LA English DT Article ID NONVANISHING LYAPUNOV EXPONENTS; NOWHERE DISPERSING BILLIARDS; GEODESIC-FLOWS; ERGODICITY; THEOREM; ENTROPY AB We give the affirmative answer to the long-standing question whether or not the mechanism of defocusing can produce a chaotic behavior in high-dimensional Hamiltonian systems. To do this we prove that billiards in a class of regions in R-n, n > 2, with focusing and flat boundary components have nonvanishing Lyapunov exponents. C1 Georgia Inst Technol, Sch Math, Atlanta, GA 30332 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Syst, Los Alamos, NM 87545 USA. RP Bunimovich, LA (reprint author), Georgia Inst Technol, Sch Math, Atlanta, GA 30332 USA. NR 33 TC 17 Z9 17 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0010-3616 J9 COMMUN MATH PHYS JI Commun. Math. Phys. PD OCT PY 1998 VL 197 IS 2 BP 277 EP 301 DI 10.1007/s002200050451 PG 25 WC Physics, Mathematical SC Physics GA 134JB UT WOS:000076738800002 ER PT J AU Benzi, M Kouhia, R Tuma, M AF Benzi, M Kouhia, R Tuma, M TI An assessment of some preconditioning techniques in shell problems SO COMMUNICATIONS IN NUMERICAL METHODS IN ENGINEERING LA English DT Article DE preconditioning; conjugate gradient; finite elements; shells ID LINEAR ELASTICITY; ELEMENT AB Preconditioned Krylov subspace methods have proved to be efficient in solving large, sparse linear systems, in many areas of scientific computing. The success of these methods in many cases is due to the existence of good preconditioning techniques. In problems of structural mechanics, like the analysis of heat transfer and deformation of solid bodies, iterative solution of the linear equation system can result in a significant reduction of computing time. Also many preconditioning techniques can be applied to these problems,thus facilitating the choice of an optimal preconditioning on the particular computer architecture available. However, in the analysis of thin shells the situation is not so transparent. It is well known that the stiffness matrices generated by the FE discretization of thin shells are very ill-conditioned. Thus, many preconditioning techniques fail to converge or they converge too slowly to be competitive with direct solvers. In this study, the performance of some general preconditioning techniques on shell problems is examined. (C) 1998 John Wiley & Sons, Ltd. C1 Helsinki Univ Technol, Lab Struct Mech, FIN-02150 Espoo, Finland. Univ Calif Los Alamos Natl Lab, Sci Comp Grp CIC19, Los Alamos, NM 87545 USA. Acad Sci Czech Republ, Inst Comp Sci, Prague 18207 8, Czech Republic. RP Kouhia, R (reprint author), Helsinki Univ Technol, Lab Struct Mech, POB 2100, FIN-02150 Espoo, Finland. RI Tuma, Miroslav/A-5946-2014; Kouhia, Reijo/G-4272-2014 OI Tuma, Miroslav/0000-0003-2808-6929; NR 18 TC 11 Z9 11 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1069-8299 J9 COMMUN NUMER METH EN JI Commun. Numer. Methods Eng. PD OCT PY 1998 VL 14 IS 10 BP 897 EP 906 DI 10.1002/(SICI)1099-0887(1998100)14:10<897::AID-CNM196>3.0.CO;2-L PG 10 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 133ZX UT WOS:000076718400001 ER PT J AU Galli, G AF Galli, G TI Tight-binding molecular dynamics for carbon systems: Fullerenes on surfaces SO COMPUTATIONAL MATERIALS SCIENCE LA English DT Article ID ELECTRONIC-STRUCTURE CALCULATIONS; CLUSTER BEAM DEPOSITION; SIMULATIONS; C-60; FILMS AB We review the applications of quantum molecular dynamics using linear scaling methods and Tight-binding Hamiltonians to carbon systems, in particular fullerenes on surfaces. We first discuss the results of C(60) impacts on a semi-conducting substrate and then present two series of computer experiments assembling small fullerenes: the deposition of C(28) clusters on a diamond surface, and the gas phase growth of a small fullerene solid. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Galli, G (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 29 TC 13 Z9 13 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0256 J9 COMP MATER SCI JI Comput. Mater. Sci. PD OCT PY 1998 VL 12 IS 3 BP 242 EP 258 DI 10.1016/S0927-0256(98)00031-7 PG 17 WC Materials Science, Multidisciplinary SC Materials Science GA 149MB UT WOS:000077608200005 ER PT J AU Sales, MA Gray, LJ AF Sales, MA Gray, LJ TI Evaluation of the anisotropic Green's function and its derivatives SO COMPUTERS & STRUCTURES LA English DT Article DE anisotropic elasticity; Green's function; residue calculus; boundary integral analysis AB An algorithm for computing the anisotropic elastic Green's function and its derivatives is presented. The method is based upon the calculus of residues, the main requirement being the computation of the roots of a sixth degree polynomial. It is demonstrated herein that this procedure is faster and more accurate than the standard Wilson-Cruse interpolation scheme, and moreover the need for extensive precalculated tables is eliminated. Published by Elsevier Science Ltd. C1 Vanderbilt Univ, Dept Math, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. RP Sales, MA (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 20 TC 48 Z9 48 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-7949 J9 COMPUT STRUCT JI Comput. Struct. PD OCT PY 1998 VL 69 IS 2 BP 247 EP 254 DI 10.1016/S0045-7949(97)00115-6 PG 8 WC Computer Science, Interdisciplinary Applications; Engineering, Civil SC Computer Science; Engineering GA 116WD UT WOS:000075747300011 ER PT J AU Ulibarri, CA Seely, HS Willis, DB AF Ulibarri, CA Seely, HS Willis, DB TI Farm profitability and BUREC water subsidies: An LP look at a region SO CONTEMPORARY ECONOMIC POLICY LA English DT Article AB Most studies of irrigation water subsidies focus on farmers' "ability-to-pay" for irrigation-related construction costs without questioning the methods used to subsidize these costs. This article shows how BUREC water subsidies could be eliminated by increasing federal water and power rates on long-term irrigation contracts. The welfare effects of this "desubsidization" are examined for California's San Joaquin Valley, which uses federal power for groundwater pumping and the conveyance of surface water. A linear-programming model provides estimates of the change in farm profitability from imposing full-cost federal water and power rates. The desubsidization has a disproportionate impact on growers of water intensive crops while benefiting non-agricultural power users and the U.S. Treasury. This points to the conclusion that charging full-cost rates would redistribute $4.58 million of profit-income per year without significant regional impacts on growers. (JEL H22, Q18, Q48). C1 New Mexico Highlands Univ, Richland, WA USA. Pacific NW Lab, Richland, WA 99352 USA. Washington State Univ, Pullman, WA 99164 USA. RP Ulibarri, CA (reprint author), New Mexico Highlands Univ, Richland, WA USA. EM carlos.ulibarri@pnl.gov; carlos.ulibarri@pnl.gov; willisd@wsu.edu NR 22 TC 0 Z9 0 U1 0 U2 1 PU WESTERN ECONOMIC ASSOC INT PI HUNTINGTON BEACH PA 7400 CENTER AVE SUITE 109, HUNTINGTON BEACH, CA 92647-3039 USA SN 1074-3529 J9 CONTEMP ECON POLICY JI Contemp. Econ. Policy PD OCT PY 1998 VL 16 IS 4 BP 442 EP 451 PG 10 WC Economics; Public Administration SC Business & Economics; Public Administration GA 133EU UT WOS:000076674200006 ER PT J AU Brunschwig, BS Creutz, C Sutin, N AF Brunschwig, BS Creutz, C Sutin, N TI Electroabsorption spectroscopy of charge transfer states of transition metal complexes SO COORDINATION CHEMISTRY REVIEWS LA English DT Review DE charge-transfer transitions; transition metal complexes; electroabsorption spectroscopy; dipole-moment changes; electronic coupling elements; solvent reorganization energies ID MIXED-VALENCE COMPLEXES; EXCITED-STATE; TO-LIGAND; SOLVENT REORGANIZATION; AMMINE COMPLEXES; RESONANCE RAMAN; DIPOLE-MOMENTS; IONIC SPECTRA; CONDUCTIVITY; ABSORPTION AB The use of electroabsorption spectroscopy to determine the dipole-moment changes that occur in the metal-to-ligand, ligand-to-metal, and metal-to-metal charge-transfer transitions in mononuclear and binuclear transition metal complexes is reviewed. The ground-excited state dipole-moment differences are much smaller than expected for the transfer of unit electronic charge between the donor and acceptor centers. The results are discussed in terms of a model in which two factors, electron delocalization and polarization of the acceptor, donor or bridging ligand electrons in response to the changed charge on the metal centers, are considered to be primarily responsible for the relatively small dipole-moment changes. The implications of the results for electronic coupling elements and reorganization energies are also discussed. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Brunschwig, BS (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. EM bsb@bnl.gov; ccreutz@bnl.gov; sutin@bnl.gov RI Brunschwig, Bruce/G-4249-2011 NR 39 TC 110 Z9 110 U1 4 U2 21 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 OCT PY 1998 VL 177 BP 61 EP 79 DI 10.1016/S0010-8545(98)00188-X PG 19 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 152QW UT WOS:000077789100004 ER PT J AU Aldykiewicz, AJ Isaacs, HS AF Aldykiewicz, AJ Isaacs, HS TI Dissolution characteristics of duplex stainless steels in acidic environments SO CORROSION SCIENCE LA English DT Article ID VIBRATING ELECTRODE TECHNIQUE; CORROSION; CERIUM AB To determine differences in the dissolution rates of the austenitic and ferritic phases in duplex stainless steels an in situ investigation was carried out in acidic solutions of 2 M H2SO4 with 2 M HCl. The current density distribution over the active surface was measured using a scanning vibrating electrode. The study demonstrated that this technique could measure differences in the dissolution rates of the austenitic and ferritic phases. These observations were validated using model calculations. The dissolution rates for the two phases peak at different potentials resulting in multiple current maxima. In addition, transients in the dissolution behavior of the two phases were observed at different potentials using optical microscopy. Electron microscopy showed aluminum and silicon enrichment at the austenitic phase after dissolution. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Aldykiewicz, AJ (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 14 TC 26 Z9 27 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0010-938X J9 CORROS SCI JI Corrosion Sci. PD OCT PY 1998 VL 40 IS 10 BP 1627 EP 1646 DI 10.1016/S0010-938X(98)00053-5 PG 20 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 149KN UT WOS:000077604500002 ER PT J AU Boudreau, N Bissell, MJ AF Boudreau, N Bissell, MJ TI Extracellular matrix signaling: integration of form and function in normal and malignant cells SO CURRENT OPINION IN CELL BIOLOGY LA English DT Article ID GENE-EXPRESSION; GROWTH-FACTOR; TERMINAL DIFFERENTIATION; INTEGRIN EXPRESSION; NEURITE OUTGROWTH; EPITHELIAL-CELLS; TENASCIN-C; ADHESION; APOPTOSIS; PROTEIN AB A growing number of studies have established reciprocal linkages between extracellular matrix (ECM)-integrins, growth factor signaling and cell-cell adhesion molecules. ECM-dependent tissue-specific gene expression has also been linked to chromatin remodeling. With respect to tissue morphogenesis and differentiation, crosstalk has been established between the ECM and the homeobox morphoregulatory genes. Each of these linkages is profoundly influenced by the cell's microenvironment and the resulting tissue form, Thus for a cell to achieve a differentiated phenotype, the ECM molecules and their receptors must integrate both form and function. In contrast, mutated genes and aberrant interactions with the microenvironment conspire to undermine this integration, often resulting in malignant transformation. C1 Univ Calif San Francisco, Surg Res Lab, San Francisco, CA 94143 USA. Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Boudreau, N (reprint author), Univ Calif San Francisco, Surg Res Lab, San Francisco, CA 94143 USA. EM mjbissell@lbl.gov FU NCI NIH HHS [CA57621, R01 CA057621, R01 CA057621-07] NR 55 TC 248 Z9 251 U1 2 U2 9 PU CURRENT BIOLOGY LTD PI LONDON PA 34-42 CLEVELAND STREET, LONDON W1P 6LE, ENGLAND SN 0955-0674 J9 CURR OPIN CELL BIOL JI Curr. Opin. Cell Biol. PD OCT PY 1998 VL 10 IS 5 BP 640 EP 646 DI 10.1016/S0955-0674(98)80040-9 PG 6 WC Cell Biology SC Cell Biology GA 128MB UT WOS:000076409600012 PM 9818175 ER PT J AU Ertl, G Sinha, SK AF Ertl, G Sinha, SK TI Editorial overview SO CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE LA English DT Editorial Material C1 Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. RP Ertl, G (reprint author), Max Planck Gesell, Fritz Haber Inst, Faradayweg 4-6, D-14195 Berlin, Germany. EM ertl@fhi-berlin.mpg.de; sksinha@aps.anl.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-0286 J9 CURR OPIN SOLID ST M JI Curr. Opin. Solid State Mat. Sci. PD OCT PY 1998 VL 3 IS 5 BP 433 EP 433 DI 10.1016/S1359-0286(98)80002-8 PG 1 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 131RD UT WOS:000076588300002 ER PT J AU Balsley, SD Gregory, RT AF Balsley, SD Gregory, RT TI Low-O-18 silicic magmas: why are they so rare? SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE magmas; O-18; assimilation; fractional crystallization ID JUAN VOLCANIC FIELD; CALDERA COMPLEX; HYDROTHERMAL SYSTEMS; MINING DISTRICT; ORE DEPOSITION; IGNEOUS ROCKS; ISOTOPE; COLORADO; OXYGEN; HYDROGEN AB Low-O-18 silicic magmas are reported from only a small number of localities (e.g., Yellowstone and Iceland), yet petrologic evidence points to upper crustal assimilation coupled with fractional crystallization (AFC) during magma genesis for nearly all silicic magmas. The rarity of low-O-18 magmas in intracontinental caldera settings is remarkable given the evidence of intense low-O-18 meteoric hydrothermal alteration in the subvolcanic remnants of larger caldera systems. In the Platoro caldera complex, regional ignimbrites (150-1000 km(3)) have plagioclase delta(18)O values of 6.8 +/- 0.1 parts per thousand, whereas the Middle Tuff, a small-volume (est. 50-100 km(3)) post-caldera collapse pyroclastic sequence, has plagioclase delta(18)O values between 5.5 and 6.8 parts per thousand. On average, the plagioclase phenocrysts from the Middle Tuff are depleted by only 0.3 parts per thousand relative to those in the regional tuffs. At Yellowstone, small-volume post-caldera collapse intracaldera rhyolites are up to 5.5 parts per thousand depleted relative to the regional ignimbrites. Two important differences between the Middle Tuff and the Yellowstone low-O-18 rhyolites elucidate the problem. Middle Tuff magmas reached water saturation and erupted explosively, whereas most of the low-O-18 Yellowstone rhyolites erupted effusively as domes or flows, and are nearly devoid of hydrous phenocrysts. Comparing the two eruptive types indicates that assimilation of low-O-18 material, combined with fractional crystallization, drives silicic melts to water oversaturation. Water saturated magmas either erupt explosively or quench as subsurface porphyries before the magmatic O-18 can be dramatically lowered. Partial melting of low-O-18 subvolcanic rocks by near-anhydrous magmas at Yellowstone produced small-volume, low-O-18 magmas directly, thereby circumventing the water saturation barrier encountered through normal AFC processes. (C) 1998 Elsevier Science B.V. All rights reserved. C1 So Methodist Univ, Dept Geol Sci, Stable Isotope Lab, Dallas, TX 75275 USA. RP Balsley, SD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 58 TC 32 Z9 33 U1 1 U2 4 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 OCT PY 1998 VL 162 IS 1-4 BP 123 EP 136 DI 10.1016/S0012-821X(98)00161-7 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 132QF UT WOS:000076640500009 ER PT J AU Bhattacharya, RN Blaugher, RD Ren, ZF Li, W Wang, JH Paranthaman, M Verebelyi, DT Christen, DK AF Bhattacharya, RN Blaugher, RD Ren, ZF Li, W Wang, JH Paranthaman, M Verebelyi, DT Christen, DK TI Superconducting epitaxial (TlBi)(0.9)Sr1.6Ba0.4Ca2Cu3Ag0.2Ox film from an electrodeposited precursor SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article AB A low-cost electrodeposition (ED) method is tested for fabricating high-temperature superconducting film. The development of biaxially textured electrodeposited (TlBi)(0.9)Sr1.6Ba0.4Ca2Cu3Ag0.2Ox (TBSBCCO-Ag) films on Ag-coated, single-crystal substrates is reported. Pole-figure measurements of electrodeposited TBSBCCO-Ag film on 300 Angstrom Ag/LaAlO3 clearly show strong biaxial texturing. The omega scan and phi scan indicate the full width at half-maximum of only 0.9 and 1.2 degrees, respectively, which suggests a very high-quality film prepared by an electrodeposition process. Transport measurements for the ED films show current density values of 3 x 10(5) A/cm(2) at 77 K in zero field. Single-layer thallium-oxide films with Pb, Bi, and Sr substitution offer the potential for operation at 77 K in practical magnetic fields of 3-5 T. (C) 1998 The Electrochemical Society. S1099-0062(98)05-052-4. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. SUNY Buffalo, Dept Chem, Buffalo, NY 14260 USA. SUNY Buffalo, CAPEM, Buffalo, NY 14260 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Bhattacharya, RN (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Ren, Zhifeng/B-4275-2014; Paranthaman, Mariappan/N-3866-2015 OI Paranthaman, Mariappan/0000-0003-3009-8531 NR 8 TC 7 Z9 7 U1 0 U2 0 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 OCT PY 1998 VL 1 IS 4 BP 165 EP 167 PG 3 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 183RW UT WOS:000079568100003 ER PT J AU Wei, J Yang, LY Harrata, AK Lee, CS AF Wei, J Yang, LY Harrata, AK Lee, CS TI High resolution analysis of protein phosphorylation using capillary isoelectric focusing electrospray ionization mass spectrometry SO ELECTROPHORESIS LA English DT Article DE capillary isoelectric focusing; electrospray ionization mass spectrometry protein phosphorylation ID OVALBUMIN; TRANSFERRIN AB On-line capillary isoelectric focusing (CIEF)-electrospray ionization - mass spectrometry (ESI-MS) as a two-dimensional separation system is employed for high resolution analysis of ovalbumin phosphorylation. On the basis of their differences in isoelectric point (pI), the mono- and diphosphoovalbumins are separated and resolved in CIEF. The focused protein zones of mono- and diphosphoovalbumins are eluted by combining gravity with cathodic mobilization. At the end of the CIEF capillary, the mobilized ovalbumin zones are analyzed by mass spectrometry coupled on-line to an electrospray interface with a coaxial sheath flow configuration. Additional ovalbumin variants within each of the mono- and diphosphoovalbumins, differing in their molecular masses due to glycosylation microheterogeneity, are easily distinguished by ESI-MS. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RP Lee, CS (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. EM chenglee@iastate.edu NR 12 TC 34 Z9 35 U1 0 U2 8 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD OCT PY 1998 VL 19 IS 13 BP 2356 EP 2360 DI 10.1002/elps.1150191316 PG 5 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 126EM UT WOS:000076280000015 PM 9788320 ER PT J AU Hoyt, JJ Wolfer, WG AF Hoyt, JJ Wolfer, WG TI Boundary element modeling of electrokinetically driven fluid flow in two-dimensional microchannels SO ELECTROPHORESIS LA English DT Article DE capillary electrophoresis; capillary electrochromatography; fluid flow; boundary element modeling ID CAPILLARY ELECTROPHORESIS; MICROCHIP; HYDRODYNAMICS; SYSTEMS; CHIP AB In recent years there has been considerable intrerest in fabricating electrophoretic separation systems on microchips. In this study the boundary element method is used to numerically model both the electrical charge density and the electrokinetically driven fluid flow velocity field in two-dimensional microchannels containing an arbitrary configuration of circular flow obstacles. An estimate of both the average velocity and the resolution has been determined for various obstacle configurations, obstacle sizes, area fractions, surface line lengths per unit area and for different values of the thickness of the electrical double layer. Based on the results, an optimal microchannel design is suggested. In addition, the recently observed phenomenon of recirculated flow in an open region of an otherwise packed electrochromatography column has been confirmed with the numerical model. C1 Sandia Natl Labs, Computat Mat Sci Dept, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA USA. RP Hoyt, JJ (reprint author), Sandia Natl Labs, Computat Mat Sci Dept, MS 9161,POB 969,7011 East Ave, Livermore, CA 94550 USA. EM jjhoyt@sandia.gov NR 22 TC 3 Z9 3 U1 0 U2 1 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD OCT PY 1998 VL 19 IS 14 BP 2432 EP 2439 DI 10.1002/elps.1150191413 PG 8 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 134AY UT WOS:000076721400012 PM 9820963 ER PT J AU Giometti, CS Tollaksen, SL Liang, XL Cunningham, ML AF Giometti, CS Tollaksen, SL Liang, XL Cunningham, ML TI A comparison of lives protein changes in mice and hamsters treated with the peroxisome proliferator Wy-14,643 SO ELECTROPHORESIS LA English DT Article DE two-dimensional electrophoresis; liver proteins; hamster; mouse ID 2-DIMENSIONAL GEL DATABASE; RAT-LIVER; TISSUE PROTEINS; GENE-REGULATION; CELL FRACTIONS; ELECTROPHORESIS; IDENTIFICATION; DEHYDROGENASE; INDUCTION; SERUM AB Interspecies differences in the liver response to Wy-14,643, a potent peroxisome proliferator in rats and mice, have been demonstrated, While both rats and mice show dramatic increases in the number of peroxisomes, the activity of peroxisomal enzymes involved in the P-oxidation of fatty acids, and heptocyte replication, Syrian hamsters have a more moderate peroxisome proliferation response and no sustained increase in cell replication. Rats and mice, but not hamsters, develop hepatocellular carcinoma after prolonged exposure to Wy-14,643. To further characterize this species difference, two-dimensional gel electrophoresis (2-DE) has been used to compare the effect of 14-day exposure to various dietary concentrations of Wy-14,643 on liver protein expression in male mice and hamsters. Digitized images of the 2-DE protein maps were searched for significant changes. The peroxisome bifunctional enzyme (PBE) enoyl CoA hydratase/3-hydroxyacyl dehydrogenase, which migrates to the same position in mouse and hamster liver protein 2-DE patterns, increased in abundance by more than three times the control level in both mice and hamsters. In addition to the quantitative change in PBE, significant quantitative changes (P < 0.001) were found in 49 mouse liver proteins (47 decreasing and 2 increasing) and in 35 hamster liver proteins (27 decreasing and 8 increasing). There was little overlap in the mouse and hamster proteins showing quantitative changes in response to Wy-14,643, with the exception of PBE and one unidentified liver protein with an approximate molecular weight of 50 000. These results show that although peroxisome proliferation occurs in the livers of both mice and hamsters exposed to Wy-14,643, other species-specific changes in proteins occur that are independent of the peroxisome proliferation response and that could be related to species-specific susceptibility or resistance to liver tumor induction. C1 Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, Argonne, IL 60439 USA. Natl Inst Environm Hlth Sci, Res Triangle Pk, NC USA. RP Giometti, CS (reprint author), Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, 9700 S Cass Ave,Bldg 2092,Room B 117, Argonne, IL 60439 USA. EM csgiometti@anl.gov FU NIEHS NIH HHS [1-YOI ES-50262] NR 22 TC 11 Z9 11 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD OCT PY 1998 VL 19 IS 14 BP 2498 EP 2505 DI 10.1002/elps.1150191424 PG 8 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 134AY UT WOS:000076721400023 PM 9820974 ER PT J AU Vine, E Lee, E Clear, R DiBartolomeo, D Selkowitz, S AF Vine, E Lee, E Clear, R DiBartolomeo, D Selkowitz, S TI Office worker response to an automated venetian blind and electric lighting system: a pilot study SO ENERGY AND BUILDINGS LA English DT Article DE commercial buildings; envelope; comfort; behavior; daylighting AB A prototype integrated, dynamic building envelops and lighting system designed to optimize daylight admission and solar heat gain rejection on a real-time basis in a commercial office building is evaluated. Office worker response to the system and occupant-based modifications to the control system are investigated to determine if the design and operation of the prototype system can be improved. Key findings from the study are: (1) the prototype integrated envelope and lighting system is ready for field testing, (2) most office workers (N = 14) were satisfied with the system, and (3) there were few complaints. Additional studies are needed to explain how illuminance distribution, lighting quality, and room design can affect workplane illuminance preferences. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Vine, E (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Environm Energy Technol Div, MS 90-2000,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 10 TC 47 Z9 47 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7788 J9 ENERG BUILDINGS JI Energy Build. PD OCT PY 1998 VL 28 IS 2 BP 205 EP 218 DI 10.1016/S0378-7788(98)00023-1 PG 14 WC Construction & Building Technology; Energy & Fuels; Engineering, Civil SC Construction & Building Technology; Energy & Fuels; Engineering GA 108VP UT WOS:000075286700011 ER PT J AU De Chant, L AF De Chant, L TI Formation of small scale folds and faults in northern Ohio SO ENGINEERING GEOLOGY LA English DT Article DE buckling stability; contemporary stress release structures; elastic model; fold; fault; stream valley anticline AB Folds and faults in the Devonian shales of the Berea area, Ohio have been analyzed on a small scale (several meters) to determine their method of formation. A simple elastic model has been developed to account for stress concentration due to lithostatic pressures induced by local relief. This analytical model is then coupled to the beam-column buckling stability theory. The possibility of failure due to faulting is also examined using the Coulomb criterion. Initial results indicate that local stresses due to topography are a probable cause of these structures, though the possible role of regional tectonic effects cannot be eliminated. The state of the local stress held and the possibility of seismic events have important implications for surface and subsurface design problems. (C) 1998 Published by Elsevier Science B.V. C1 Chevron Petr Technol Co, La Habra, CA 90633 USA. RP De Chant, L (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 20 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0013-7952 J9 ENG GEOL JI Eng. Geol. PD OCT PY 1998 VL 50 IS 3-4 BP 329 EP 335 DI 10.1016/S0013-7952(98)00033-7 PG 7 WC Engineering, Geological; Geosciences, Multidisciplinary SC Engineering; Geology GA 133RP UT WOS:000076699800008 ER PT J AU Lybarger, JA Lee, R Vogt, DP Perhac, RM Spengler, RF Brown, DR AF Lybarger, JA Lee, R Vogt, DP Perhac, RM Spengler, RF Brown, DR TI Medical costs and lost productivity from health conditions at volatile organic compound-contaminated superfund sites SO ENVIRONMENTAL RESEARCH LA English DT Article DE costs; economic impact; superfund; hazardous waste; volatile organic compounds ID CONGENITAL-MALFORMATIONS AB This paper estimates the health costs at Superfund sites for conditions associated with volatile organic compounds (VOCs) in drinking water. Health conditions were identified from published literature and registry information as occurring at excess rates in VOC-exposed populations. These health conditions mere: (1) some categories of birth defects, (2) urinary tract disorders, (3) diabetes, (4) eczema and skin conditions, (5) anemia, (6) speech and hearing impairments in children under 10 years of age, and (7) stroke, Excess rates were used to estimate the excess number of cases occurring among the total population living within one-half mile of 258 Superfund sites, These sites had evidence of completed human exposure pathways for VOCs in drinking water, For each type of medical condition, an individual's expected medical costs, long-term care costs, and lost work time due to illness or premature mortality were estimated. Costs were calculated to be approximately $330 million per year, in the absence of any remediation or public health intervention programs. The results indicate the general magnitude of the economic burden associated with a limited number of contaminants at a portion of all Superfund sites, thus suggesting that the burden would be greater than that estimated in this study if all contaminants at all Superfund sites could be taken into account. (C) 1998 Academic Press. C1 Agcy Tox Substances & Dis Registry, Div Hlth Studies, Atlanta, GA 30333 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Joint Inst Energy & Environm, Oak Ridge, TN USA. Univ Tennessee, Oak Ridge, TN USA. RP Lybarger, JA (reprint author), Agcy Tox Substances & Dis Registry, Div Hlth Studies, 1600 Clifton Rd, Atlanta, GA 30333 USA. RI Brown, David /A-4083-2008 NR 33 TC 6 Z9 6 U1 1 U2 4 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0013-9351 J9 ENVIRON RES JI Environ. Res. PD OCT PY 1998 VL 79 IS 1 BP 9 EP 19 DI 10.1006/enrs.1998.3845 PG 11 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA 121RE UT WOS:000076027100002 PM 9756676 ER PT J AU Gao, HZ Zepp, RG AF Gao, HZ Zepp, RG TI Factors influencing photoreactions of dissolved organic matter in a coastal river of the southeastern United States SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID HUMIC SUBSTANCES; PHOTOCHEMICAL DEGRADATION; INORGANIC CARBON; SURFACE WATERS; NATURAL-WATERS; PHOTODEGRADATION; SEAWATER; CYCLE; SEA; PHOTOPRODUCTION AB Photoreactions of dissolved organic matter can affect the oxidizing capacity, nutrient dynamics, trace gas exchange, and color of surface waters. This study focuses on factors that affect the photoreactions of the colored dissolved organic matter (CDOM) in the Satilla River, a coastal river that has high concentrations of dissolved organic carbon (DOC) (2.0 +/- 0.2 mM C) and iron (12 +/- 2 mu M) in its freshwater reach. Quantum yields for the photoproduction of dissolved inorganic carbon (DIC) and carbon monoxide (CO) from Satilla CDOM decreased exponentially in the 300-450 nm spectral region. Photoreaction of the CDOM in sunlight caused a decrease in UV and visible absorbance that occurred most rapidly in the UV-B (280-315 nm) region, indicating that CDOM photoreactions can enhance exposure of aquatic organisms to DNA-damaging UV radiation. The role of iron in the photooxidation was investigated by adding fluoride ions or deferoxamine mesylate (DFOM) to the water to form unreactive Fe3+ complexes, thus inhibiting iron photoreduction and slowing CDOM photooxidation. Using this method, it was demonstrated that the photoformation of DIG, CO, and NH4+ is strongly affected by iron catalysis in the Satilla River water. Increasing the dioxygen content and lowering the pH accelerated the photoreaction of the CDOM. CDOM photoreaction was accompanied by conversion of dissolved iron and carbon to particulate forms. Such "photocoagulation" may contribute to the transport of iron and carbon from surface waters to sediments in sunlit, well-stratified aquatic ecosystems. C1 US EPA, Natl Exposure Res Lab, Ecosyst Res Div, Athens, GA 30605 USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. RP Zepp, RG (reprint author), US EPA, Natl Exposure Res Lab, Ecosyst Res Div, Athens, GA 30605 USA. EM zepp.richard@epamail.epa.gov NR 50 TC 252 Z9 276 U1 9 U2 91 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 OCT 1 PY 1998 VL 32 IS 19 BP 2940 EP 2946 DI 10.1021/es9803660 PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 125DR UT WOS:000076222600039 ER PT J AU Theodorakis, CW Bickham, JW Elbl, T Shugart, LR Chesser, RK AF Theodorakis, CW Bickham, JW Elbl, T Shugart, LR Chesser, RK TI Genetics of radionuclide-contaminated mosquitofish populations and homology between Gambusia affinis and G. holbrooki SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE population genetics; Gambusia; radiation; evolutionary toxicology; randomly amplified polymorphic DNA ID ALLOZYME GENOTYPE; MERCURY POLLUTION; INORGANIC MERCURY; EXPOSURE; RADIATION; GIRARD; ECOTOXICOLOGY; POLYMORPHISMS; RESISTANCE; RESERVOIR AB The effects of radionuclide contamination on generic structure of eastern mosquitofish (Gambusia holbrooki) populations from the U.S. Department of Energy's Savannah River Site (SRS) were investigated to develop methods of assessing ecological risk of chronic exposures to xenobiotics. Fish from two contaminated and two reference sites were examined by the randomly amplified polymorphic DNA (RAPD) technique, which revealed that the frequency of three markers was greater in the contaminated than the reference sites and that the frequency of two markers was greater in the reference than in the contaminated sites. A previous study examined populations of western mosquitofish (G. affinis) from the Oak Ridge National Laboratory (ORNL) and found that certain RAPD markers were present in radionuclide-contaminated ORNL populations at a higher frequency than in reference populations. The "contaminant-indicative" markers observed in the SRS populations were the same size and amplified by the same polymerase chain reaction primers used in the ORNL study. Southern blot analysis revealed that the SRS G, holbrooki contaminant-indicative markers were homologous to the ORNL G. affinis contaminant-indicative markers. The observation that two species show similar patterns of band frequency shifts at two separate localities is consistent with the hypothesis that these DNA markers may originate from genetic elements that provide a selective advantage in contaminated habitats. Thus, the methodology used in these studies may prove to be useful to indicate population-level effects of environmental contamination. C1 Texas A&M Univ, Dept Wildlife & Fisheries Sci, College Stn, TX 77843 USA. Univ Penn, Dept Cell & Mol Biol, Philadelphia, PA 19102 USA. LR Shugart & Associates, Oak Ridge, TN 37831 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Bickham, JW (reprint author), Texas A&M Univ, Dept Wildlife & Fisheries Sci, College Stn, TX 77843 USA. EM j-bickham@tamu.edu NR 44 TC 32 Z9 34 U1 2 U2 9 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD OCT PY 1998 VL 17 IS 10 BP 1992 EP 1998 DI 10.1897/1551-5028(1998)017<1992:GORCMP>2.3.CO;2 PG 7 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 121WJ UT WOS:000076038500015 ER PT J AU Keane, B Smith, MK Rogstad, SH AF Keane, B Smith, MK Rogstad, SH TI Genetic variation in red raspberries (Rubus idaeus L.; Rosaceae) from sites differing in organic pollutants compared with synthetic tandem repeat DNA probes SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE asexual reproduction; biomonitoring; DNA fingerprinting; organic contaminants; population genetics ID ALLOZYME POLYMORPHISMS; POPULATION; FINGERPRINTS; HETEROZYGOSITY; DIVERSITY; SELECTION; BARNACLES; M13 AB Two synthetic tandem repetitive DNA probes were used to compare genetic variation at variable-number-tandem-repeat (VNTR) loci among Rubus idaeus L. var, strigosus (Michx.) Maxim. (Rosaceae) individuals sampled at eight sites contaminated by pollutants (N = 39) and eight adjacent uncontaminated sites (N = 38; distances separating sites ranged from 5 to 350 m). For the 77 plants analyzed, the mean number of bands scored per individual was 16.5 (SD = 3.5). Mean genetic similarity (0.51) and heterozygosity (0.62) across all plants from contaminated sites did not differ significantly from that among all plants from uncontaminated sites (mean similarity = 0.52; mean heterozygosity = 0.63). Nor did similarity and heterozygosity differ between contaminated and uncontaminated sites when estimates of these values within each of the 16 sites were compared. Estimates of F(st) (0.01-0.04) indicated little genetic differentiation between plants from contaminated and uncontaminated sites. However, relative to plants from uncontaminated sites, plants from contaminated sites possessed significantly fewer private alleles (1 vs 18; p < 0.001) and alleles per individual (mean = 15.2 vs 17.9; p = 0.0002). Considering the 16 sites individually, uncontaminated sites possess significantly more population bands (p = 0.015), private alleles (p = 0.01), and alleles per individual (p = 0.027). These differences were distributed across sites rather than resulting from large, idiosyncratic differences attributable to one or a few outlier sites. The findings of this study suggest that a loss of genetic variation among R. idaeus individuals growing in impacted areas has occurred at all eight sites, and that VNTR markers may be useful biological indicators of plant populations under stress from human perturbations. In addition, extensive clonal spread of this species, previously documented for other species of Rubus, was not detected. C1 Univ Cincinnati, Dept Biol Sci ML6, Cincinnati, OH 45221 USA. Oak Ridge Inst Sci & Educ, Sci Engn Educ Div, Oak Ridge, TN 37831 USA. US EPA, Natl Exposure Res Lab, Ecol Exposure Res Div, Cincinnati, OH 45268 USA. RP Rogstad, SH (reprint author), Univ Cincinnati, Dept Biol Sci ML6, Cincinnati, OH 45221 USA. EM steven.rogstad@uc.edu NR 41 TC 8 Z9 8 U1 1 U2 3 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD OCT PY 1998 VL 17 IS 10 BP 2027 EP 2034 DI 10.1897/1551-5028(1998)017<2027:GVIRRR>2.3.CO;2 PG 8 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 121WJ UT WOS:000076038500019 ER PT J AU Dewald, A Schmidt, A Alexius, G Vogel, O Chakrawarthy, RS Bazzacco, D von Brentano, P Gizon, A Gizon, J Lunardi, S Napoli, DR Pavan, P Alvarez, CR Wiedenhover, I AF Dewald, A Schmidt, A Alexius, G Vogel, O Chakrawarthy, RS Bazzacco, D von Brentano, P Gizon, A Gizon, J Lunardi, S Napoli, DR Pavan, P Alvarez, CR Wiedenhover, I TI Five-quasiparticle bands in Ba-127 SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article AB High spin states in Ba-127 have been investigated with the fusion-evaporation reaction Zr-96 (S-36, 5n) Ba-127 at a beam energy of 150 MeV with the GASP-spectrometer at INFN in Legnaro, Italy. The level scheme could be extended to high spins resulting in the observation of five-quasiparticle states. Altogether 15 band structures a ere placed in the level scheme. C1 Univ Cologne, Inst Kernphys, D-50937 Cologne, Germany. Univ Grenoble 1, Inst Sci Nucl, F-38036 Grenoble, France. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Sezione Padova, Padua, Italy. Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Legnaro, Italy. Argonne Natl Lab, Argonne, IL 60439 USA. RP Dewald, A (reprint author), Univ Cologne, Inst Kernphys, Zulpicher Str 77, D-50937 Cologne, Germany. RI Dewald, Alfred/O-5810-2015; Napoli, Daniel R./D-9863-2012 OI Napoli, Daniel R./0000-0002-8154-6958 NR 6 TC 4 Z9 4 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 OCT PY 1998 VL 3 IS 2 BP 103 EP 105 DI 10.1007/s100500050153 PG 3 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 137MP UT WOS:000076918800002 ER PT J AU Bhattacharyya, P Zhang, CT Daly, PJ Fornal, B Grabowski, ZW Ahmad, I Lauritsen, T Morss, LR Urban, W Nowak, A Phillips, WR Durell, JL Leddy, MJ Smith, AG Varley, BJ Schulz, N Lubkiewicz, E Bentaleb, M Blomqvist, J AF Bhattacharyya, P Zhang, CT Daly, PJ Fornal, B Grabowski, ZW Ahmad, I Lauritsen, T Morss, LR Urban, W Nowak, A Phillips, WR Durell, JL Leddy, MJ Smith, AG Varley, BJ Schulz, N Lubkiewicz, E Bentaleb, M Blomqvist, J TI Three-valence-particle fission product Sb-135(51)84 SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID GAMMA-RAY; STATES AB By analysis of fission product gamma-ray data measured at Eurogam II using a Cm-248 source, yrast levels up to about 2 MeV in the N=84 three-particle nucleus Sb-135 have been identified. These levels are interpreted as pi g(7/2)nu f(7/2)(2) and pi g(7/2)nu f(7/2)h(9/2) states with the help of shell model calculations using empirical nucleon-nucleon interactions. C1 Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. Univ Manchester, Dept Phys, Manchester M13 9PL, Lancs, England. Univ Manchester, Dept Astron, Manchester M13 9PL, Lancs, England. Univ Strasbourg 1, Inst Rech Subatom, F-67037 Strasbourg, France. Royal Inst Technol, Dept Phys Frescati, S-10405 Stockholm, Sweden. RP Bhattacharyya, P (reprint author), Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. NR 7 TC 19 Z9 20 U1 0 U2 1 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 OCT PY 1998 VL 3 IS 2 BP 109 EP 110 DI 10.1007/s100500050155 PG 2 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 137MP UT WOS:000076918800004 ER PT J AU Nowak, A Urban, W Rejmund, M Durell, JL Leddy, MJ Jones, MA Phillips, WR Smith, AG Varley, BJ Ahmad, I Morss, LR Bentaleb, M Lubkiewicz, E Schulz, N AF Nowak, A Urban, W Rejmund, M Durell, JL Leddy, MJ Jones, MA Phillips, WR Smith, AG Varley, BJ Ahmad, I Morss, LR Bentaleb, M Lubkiewicz, E Schulz, N TI Structure of Te-136 and the problem of mass of Te-134 SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID NEUTRON-RICH; EXCITATIONS; NUCLEI; FISSION; SN-132; ND-144 AB Neutron-rich, N=84 nuclei from the Sn-132 region, populated in spontaneous fission of Cm-248, hal-e been studied with EUROGAM 2. Excited states and their spins and parities in the Te-136 nucleus were established up to 17 (h) over bar. OXBASH code calculations support the experimental identification of maximum aligned configurations in 136Te. Empirical shell model calculations for the I-pi = 14(+) level in 136Te indicate that the adopted mass of the Te-134 nucleus should be lowered by 200(80) keV. C1 Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. Univ Manchester, Dept Phys & Astron, Schuster Lab, Manchester M13 9PL, Lancs, England. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Strasbourg, Ctr Rech Nucl, IN2P3 CNRS, F-67037 Strasbourg, France. RP Univ Warsaw, Inst Expt Phys, Hoza 69, PL-00681 Warsaw, Poland. NR 14 TC 7 Z9 7 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6001 EI 1434-601X J9 EUR PHYS J A JI Eur. Phys. J. A PD OCT PY 1998 VL 3 IS 2 BP 111 EP 113 DI 10.1007/s100500050156 PG 3 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 137MP UT WOS:000076918800005 ER PT J AU Burvenich, T Rutz, K Bender, M Reinhard, PG Maruhn, JA Greiner, W AF Burvenich, T Rutz, K Bender, M Reinhard, PG Maruhn, JA Greiner, W TI Superheavy nuclei in deformed mean-field calculations SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID GROUND-STATE PROPERTIES; EFFECTIVE FORCES; DRIP-LINE; PARAMETRIZATION; STABILITY; ELEMENTS; SPACE; DECAY AB The ground-state properties of superheavy nuclei are investigated within various parametrisations of relativistic and nonrelativistic nuclear mean-field models. The heaviest known ei en-even nuclei starting with Z = 98 are used as a benchmark to estimate the predictive power of the models and forces. From that starting point, deformed doubly magic nuclei are searched in the region 100 less than or equal to Z less than or equal to 130 and 142 less than or equal to N less than or equal to 190. C1 Univ Frankfurt, Inst Theoret Phys, D-60325 Frankfurt, Germany. Gesell Schwerionenforsch GmbH, D-64291 Darmstadt, Germany. Univ Erlangen Nurnberg, Inst Theoret Phys 2, D-91058 Erlangen, Germany. Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. RP Burvenich, T (reprint author), Univ Frankfurt, Inst Theoret Phys, Robert Mayer Str 10, D-60325 Frankfurt, Germany. RI Bender, Michael/B-9004-2009 NR 42 TC 59 Z9 60 U1 0 U2 1 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 OCT PY 1998 VL 3 IS 2 BP 139 EP 147 DI 10.1007/s100500050160 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 137MP UT WOS:000076918800009 ER PT J AU Schubert, C AF Schubert, C TI The structure of the Bern-Kosower integrand for the N-gluon amplitude SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID WORLDLINE PATH-INTEGRALS; STRING-BASED METHODS; GAUGE-THEORIES; FIELD-THEORY; GREEN-FUNCTIONS; LINE FORMALISM; LOOP; COUPLINGS; FERMIONS; DIAGRAMS AB An ambiguity inherent in the partial integration procedure leading to the Bern-Kosower rules is fixed in a way which preserves the complete permutation symmetry in the scattering states. This leads to a canonical version of the Bern-Kosower representation for the one-loop N-photon/gluon amplitudes, and to a natural decomposition of those amplitudes into permutation symmetric gauge invariant partial amplitudes. This decomposition exhibits a simple recursive structure. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Humboldt Univ, Inst Phys, D-10115 Berlin, Germany. RP Schubert, C (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. EM schubert@qft2.physik.hu-berlin.de NR 36 TC 13 Z9 13 U1 0 U2 1 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 OCT PY 1998 VL 5 IS 4 BP 693 EP 699 PG 7 WC Physics, Particles & Fields SC Physics GA 134MY UT WOS:000076747900010 ER PT J AU Vitanov, NV Shore, BW Bergmann, K AF Vitanov, NV Shore, BW Bergmann, K TI Adiabatic population transfer in multistate chains via dressed intermediate states SO EUROPEAN PHYSICAL JOURNAL D LA English DT Article ID STIMULATED RAMAN-SCATTERING; 3-LEVEL SYSTEM DRIVEN; DELAYED LASER-PULSES; MULTILEVEL SYSTEMS; MAGNETIC SUBLEVELS; VIBRATIONAL LEVELS; PASSAGE; EXCITATION; MOLECULES; DISSOCIATION AB The well-known process of stimulated Raman adiabatic passage (STIRAP) provides a robust technique for achieving complete population transfer between the first and last state of a three-state chain, with little population, even transiently, in the intermediate state. The extension of STIRAP to general N-state chainwise-linked systems continues to generate interest. Recently Malinovsky and Tanner (Phys. Rev. A 56, 4929 (1997)) have shown with numerical simulation that a resonant pulse sequence, which they term "straddle STIRAP", can produce (under appropriate conditions, including specific pulse areas) complete population transfer with very little population in intermediate states. Their proposal supplements a pair of counterintuitively ordered delayed laser pulses, driving the first and last transition of the chain and corresponding to the pump and Stokes pulses in STIRAP, with one or more additional strong pulses of longer duration which couple the intermediate transition(s) and overlap both the pump and the Stokes pulses. In this paper, we modify the "straddling" Malinovsky-Tannor pulse sequence so that the intermediate couplings are constant (and strong), at least during the times when the pump and Stokes pulses are present, and the intermediate states therefore act as a strongly coupled subsystem with constant eigenvalues. Under this condition, we show that the original N-state chain is mathematically equivalent to a system comprising N - 2 parallel Lambda-transitions, in which the initial state is coupled simultaneously to N - 2 dressed intermediate states, which in turn are coupled to the final state. The population transfer is optimized by suitably tuning the pump and Stokes frequencies to resonance with one of these dressed intermediate states, which effectively acts as the single intermediate state in a three-state STIRAP-like process. We show that tuning to a dressed intermediate state turns the system (for both odd N and even N) into a three-state system - with all of the properties of conventional STIRAP (complete population transfer: little transient population in the intermediate states, insensitivity to variations in the laser parameters, such as pulse area). The success of the tuning-to-dressed-state idea is explained by using simple analytic approaches and illustrated with numerical simulations for four-, five-, six- and seven-state systems. C1 Univ Helsinki, Inst Phys, FIN-00014 Helsinki, Finland. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Kaiserslautern, Fachbereich Phys, D-67653 Kaiserslautern, Germany. RP Vitanov, NV (reprint author), Univ Helsinki, Inst Phys, POB 9, FIN-00014 Helsinki, Finland. RI Vitanov, Nikolay/A-1248-2013; BERGMANN, KLAAS/D-5543-2011; OI Vitanov, Nikolay/0000-0002-8599-4766 NR 44 TC 38 Z9 39 U1 0 U2 7 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6060 J9 EUR PHYS J D JI Eur. Phys. J. D PD OCT PY 1998 VL 4 IS 1 BP 15 EP 29 DI 10.1007/s100530050180 PG 15 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 143CD UT WOS:000077236700003 ER PT J AU Hipwell, MC Tien, CL AF Hipwell, MC Tien, CL TI The dual beam picosecond continuum technique for measurement of short-time-scale transmission spectra SO EXPERIMENTAL HEAT TRANSFER LA English DT Article ID SPECTROSCOPY AB In this work, a dual-beam measurement technique ir presented to measure the short-time-scale optical properties of novel materials. It ir shown that the picosecond continuum probe source obtained from nonlinear interaction with H2O/D2O is highly variable and does not permit detection of small changes in absorption/transmission spectra. The dual-beam approach is proposed to allow simultaneous measurement of a sample's properties in both the excited and steady states. As an example, the technique is applied to the picosecond transmission spectrum of light-emitting porous silicon. Photo-induced absorption is observed at a level that could not be detected without the new technique. C1 Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Hipwell, MC (reprint author), Seagate Technol, Bloomington, MN 55435 USA. NR 13 TC 1 Z9 1 U1 1 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0891-6152 J9 EXP HEAT TRANSFER JI Exp. Heat Transf. PD OCT-DEC PY 1998 VL 11 IS 4 BP 281 EP 297 DI 10.1080/08916159808946566 PG 17 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 142LD UT WOS:000077201200001 ER PT J AU Krause, DS Mucenski, ML Lawler, AM May, WS AF Krause, DS Mucenski, ML Lawler, AM May, WS TI CD34 expression by embryonic hematopoietic and endothelial cells does not require c-Myb SO EXPERIMENTAL HEMATOLOGY LA English DT Article DE CD34; c-Myb; hematopoiesis; transcriptional regulation; murine ID INDUCED ERYTHROID-DIFFERENTIATION; STEM-CELLS; CONSTITUTIVE EXPRESSION; MYELOID DIFFERENTIATION; GENE-EXPRESSION; ANTIGEN CD34; MURINE CD34; M1 CELLS; ES CELLS; PROGENITOR AB CD34 is a cell-surface glycoprotein expressed in a developmental, stage-specific manner by bone marrow stem and progenitor cells. In this study we explored a possible role for c-Myb in CD34 regulation during developmental hematopoiesis. The results indicate that c-Myb can induce CD34 expression in hematopoietic and nonhematopoietic cells, and that murine CD34 promoter activity is enhanced in myeloid cells transgenic for c-Myb. To test whether c-Myb is necessary for CD34 expression during developmental hematopoiesis in vitro, c-Myb-null D3 embryonic stem (ES) cells were analyzed for their ability to develop CD34(+) hematopoietic cells in vitro. CD34 promoter activity in transient transfections and CD34 upregulation during ES cell differentiation into embryoid bodies was identical in wild-type and c-Myb-null ES cells, indicating that c-Myb is not required for CD34 expression. CD34 protein is expressed on both hematopoietic and endothelial cells of the E8.5 blood islands during the development of c-Myb-null embryos, and expression is nearly identical in wild-type and c-Myb-null embryos. However, in E12.5 c-Myb-null embryos, the majority of identifiable CD34(+) cells in the developing liver are endothelial rather than hematopoietic, which is consistent with the absence of colony-forming units in c-Myb-null embryos and developing ES cells. These data indicate that c-Myb is not required for CD34 expression in endothelial or primitive hematopoietic cells in the yolk sac, but is necessary for definitive hematopoiesis. C1 Yale Univ, Sch Med, Dept Lab Med, New Haven, CT 06520 USA. Johns Hopkins Univ, Sch Med, Johns Hopkins Oncol Ctr, Baltimore, MD 21205 USA. Johns Hopkins Univ, Dept Gynecol & Obstet, Baltimore, MD USA. Oak Ridge Natl Lab, Div Biol, Oak Ridge, TN 37831 USA. Univ Texas, Med Branch, Sealy Ctr Oncol & Hematol, Galveston, TX 77550 USA. RP Krause, DS (reprint author), Yale Univ, Sch Med, Dept Lab Med, 333 Cedar St,POB 208035, New Haven, CT 06520 USA. FU NCI NIH HHS [CA44649, CA58492] NR 38 TC 12 Z9 15 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0301-472X J9 EXP HEMATOL JI Exp. Hematol. PD OCT PY 1998 VL 26 IS 11 BP 1086 EP 1092 PG 7 WC Hematology; Medicine, Research & Experimental SC Hematology; Research & Experimental Medicine GA 124PL UT WOS:000076190800014 PM 9766450 ER PT J AU Rubes, J Lowe, X Moore, D Perreault, S Slott, V Evenson, D Selevan, SG Wyrobek, AJ AF Rubes, J Lowe, X Moore, D Perreault, S Slott, V Evenson, D Selevan, SG Wyrobek, AJ TI Smoking cigarettes is associated with increased sperm disomy in teenage men SO FERTILITY AND STERILITY LA English DT Article; Proceedings Paper CT 45th Annual Meeting of the American-Society-of-Human-Genetics CY OCT 24-28, 1995 CL MINNEAPLOIS, MINNESOTA SP Amer Soc Human Genet DE cigarette-smoking lifestyle; sperm disomy; multicolor sperm FISH; CASA; SCSA; semen quality; urine cotinine ID IN-SITU HYBRIDIZATION; ENVIRONMENTAL TOBACCO-SMOKE; NUMERICAL CHROMOSOME-ABNORMALITIES; CHILDHOOD BRAIN-TUMORS; ALCOHOL-CONSUMPTION; DNA DENATURATION; COFFEE-DRINKING; PATERNAL AGE; RISK-FACTORS; HEALTHY-MEN AB Objective: To determine whether moderate cigarette smoking and alcohol consumption in teenage men is associated with increases in disomic sperm and detectable changes in semen quality. Design: Cohort study. Setting: Military recruiting station, Teplice, Czech Republic. Patient(s): Ten current smokers (20 cigarettes per day for at least 2 years, exposure confirmed by urine cotinine) who also consumed alcohol and 15 nonsmokers. All patients were exactly 18 years old, healthy, and of unproven fertility. Main Outcome Measure(s): Sperm aneuploidy by multicolor fluorescence in situ hybridization for chromosomes 8, X, and Y; conventional semen analyses; computer-aided sperm analysis for motility; and sperm chromatin structure analysis. Results: Smokers showed elevated frequencies of sperm aneuploidy (Y disomy, P <0.001; aggregate of X, Y, and 8 disomies, P <0.01); reduced linearity of sperm motion (P <0.05); and more "round-headed" sperm (P <0.01). Smokers' semen contained fewer sperm (P <0.001) and fewer motile sperm (P <0.02), which was attributable, in part, to shorter abstinence intervals among smokers (P <0.02). Conclusion(s): Cigarette smoking among teenagers was associated with increases in disomic sperm and a diminution in Specific aspects of semen quality. Such defects may affect male fertility and may increase future chances of fathering Offspring with aneuploidy syndromes. (Fertil Steril(R) 1998;70:715-23. (C) 1998 by American Society for Reproductive Medicine.). C1 Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Vet Res Inst, CS-62132 Brno, Czech Republic. US EPA, Res Triangle Pk, NC 27711 USA. Univ N Carolina, Chapel Hill, NC USA. S Dakota State Univ, Brookings, SD 57007 USA. US EPA, Washington, DC 20460 USA. RP Wyrobek, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Biol & Biotechnol Res Program, L-452,7000 East Ave, Livermore, CA 94550 USA. EM wyrobek1@linl.gov NR 62 TC 154 Z9 163 U1 1 U2 8 PU AMER SOC REPRODUCTIVE MEDICINE PI BIRMINGHAM PA 1209 MONTGOMERY HIGHWAY, BIRMINGHAM, AL 35216-2809 USA SN 0015-0282 J9 FERTIL STERIL JI Fertil. Steril. PD OCT PY 1998 VL 70 IS 4 BP 715 EP 723 DI 10.1016/S0015-0282(98)00261-1 PG 9 WC Obstetrics & Gynecology; Reproductive Biology SC Obstetrics & Gynecology; Reproductive Biology GA 130CE UT WOS:000076505400019 PM 9797104 ER PT J AU Burakovsky, L AF Burakovsky, L TI Relativistic statistical mechanics and particle spectroscopy SO FOUNDATIONS OF PHYSICS LA English DT Article; Proceedings Paper CT 1st International Conference on Parametrized Relativistic Quantum Theory (PRQT 98) CY FEB 09-11, 1998 CL HOUSTON, TEXAS ID HOT HADRONIC MATTER; MASS-DISTRIBUTION; QUANTUM-MECHANICS; MESON NONET; SPECTRUM; EVENTS AB The formulation of manifestly covariant relativistic statistical mechanics as the description of ail ensemble of events in spacetime parametrized by an invariant proper-time tau is reviewed. The linear and cubic mass spectra, which result from this formulation (the latter with the inclusion of anti-events) as the actual spectra of an individual hadronic multiplet and hot hadronic matter, respectively, are discussed. these spectra allow one to predict the masses of particles nucleated to quasi-levels in such an ensemble. As an example, the masses of the ground-state mesons and baryons are considered; the results are in excellent agreement with the measured hadron masses. Additivity of inverse Regge slopes is established and shown to be consistent with available experimental data on the D meson and Lambda(c) baryon production. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Burakovsky, L (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-8, Los Alamos, NM 87545 USA. NR 45 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0015-9018 J9 FOUND PHYS JI Found. Phys. PD OCT PY 1998 VL 28 IS 10 BP 1577 EP 1594 DI 10.1023/A:1018890402963 PG 18 WC Physics, Multidisciplinary SC Physics GA 148CJ UT WOS:000077535000007 ER PT J AU Burakovsky, L AF Burakovsky, L TI Glueball spectroscopy in Regge phenomenology SO FOUNDATIONS OF PHYSICS LA English DT Article; Proceedings Paper CT 1st International Conference on Parametrized Relativistic Quantum Theory (PRQT 98) CY FEB 09-11, 1998 CL HOUSTON, TEXAS ID MESON NONET; MASS; DIMENSIONS; SPECTRUM; PHYSICS AB We show that linear Regge trajectories for mesons and glueballs, and the cubic mass spectrum associated with them, determine a relation between the masses of the rho meson and the scalar glueball, M(0(++)) = 3/root 2M(rho), which implies M(0(++)) = 1620 +/- 10 MeV. We also discuss relations between the masses of the scalar, tensor and 3(--) glueballs, M(2(++)) = root 2M(0(++)), M(3(--)) = 2M(0(++)), which imply M(2(++)) = 2290 +/- 15 MeV, M(3(--)) = 3240 +/- 20 MeV. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Burakovsky, L (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-8, Los Alamos, NM 87545 USA. NR 36 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0015-9018 J9 FOUND PHYS JI Found. Phys. PD OCT PY 1998 VL 28 IS 10 BP 1595 EP 1605 DI 10.1023/A:1018842519801 PG 11 WC Physics, Multidisciplinary SC Physics GA 148CJ UT WOS:000077535000008 ER PT J AU Tonn, BE Petrich, C AF Tonn, BE Petrich, C TI Everyday life's constraints on citizenship in the United States SO FUTURES LA English DT Article ID HUMAN-RIGHTS; DEMOCRACY; FUTURES AB Citizenship is a topic of important concern to the futures community. This paper discusses five serious kinds of constraints that people in the United States must overcome to meet their citizenship responsibilities. The constraints are: work (e.g. long hours, disruptive schedules, transfers); consumerism (e.g. time spent watching television, shopping, and engaging in entertainment activities); lack of social capital (e.g. social networks not 'tight' enough to foster people working together to address community issues); personal fears and anxieties (e.g. fear of reprisals from neighbors); and the built environment (e.g. lack of meeting places, car- rather than people-oriented land uses). The charge to futurists is to image and work toward implementing futures that overcome these constraints. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Ernst & Young Ctr Business Innovat, Cambridge, MA 02142 USA. RP Tonn, BE (reprint author), Oak Ridge Natl Lab, POB 2002, Oak Ridge, TN 37831 USA. EM bet@ornl.gov; care.petrich@ey.com NR 63 TC 14 Z9 14 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0016-3287 J9 FUTURES JI Futures PD OCT PY 1998 VL 30 IS 8 BP 783 EP 813 DI 10.1016/S0016-3287(98)00085-8 PG 31 WC Economics; Planning & Development SC Business & Economics; Public Administration GA 133HB UT WOS:000076680200003 ER PT J AU Avet-Loiseau, H Garand, R Gaillard, F Daviet, A Mellerin, MP Robillard, N Bouyge, I Arcot, S Batzer, M Talmant, P Harousseau, JL Milpied, N Bataille, R AF Avet-Loiseau, H Garand, R Gaillard, F Daviet, A Mellerin, MP Robillard, N Bouyge, I Arcot, S Batzer, M Talmant, P Harousseau, JL Milpied, N Bataille, R TI Detection of t(11;14) using interphase molecular cytogenetics in mantle cell lymphoma and atypical chronic lymphocytic leukemia SO GENES CHROMOSOMES & CANCER LA English DT Article ID POLYMERASE CHAIN-REACTION; NON-HODGKINS-LYMPHOMAS; IN-SITU HYBRIDIZATION; BCL-1; REARRANGEMENTS; OVEREXPRESSION; TRANSLOCATION; GENE; CLASSIFICATION; DIAGNOSIS AB The chromosomal translocation t(11;14)(q13;q32) fuses the IGH and CCND1 genes and leads to cyclin D1 overexpression. This genetic abnormality is the hallmark of mantle cell lymphoma (MCL), but is also found in some cases of atypical chronic lymphocytic leukemia (CLL), characterized by a poor outcome. For an unequivocal assessment of this specific chromosomal rearrangement on interphase cells, we developed a set of probes for fluorescence in situ hybridization (FISH). Northern blotting was performed for analysis of the cyclin D1 expression in 18 patients. Thirty-eight patients, with either a typical MCL leukemic phase (17 patients) or atypical CLL with an MCL-type immunophenotype, i.e., CD19(+), CD5(+), CD23(-/low), CD79b/slgM(D)(++), and FMC7(+) (21 patients), were analyzed by dual-color interphase FISH. We selected an IGH-specific BAC probe (covering the JH and first constant regions) and a commercially available CCND1 probe. An IGH-CCND1 fusion was detected in 28 of the 38 patients (17 typical MCL and 11 cases with CLL). Cyclin D1 was not overexpressed in two patients with typical MCL and an IGH-CCND1 fusion. In view of the poor prognosis associated with MCL and t(11;14)-positive CLL, we conclude that this set of probes is a valuable and reliable tool for a rapid diagnosis of these entities. (C) 1998 Wiley-Liss. Inc. C1 Univ Hosp, Hematol Lab, Nantes, France. Univ Hosp, Pathol Lab, Nantes, France. INSERM U463, Nantes, France. Univ Calif Lawrence Livermore Natl Lab, Ctr Human Genet, Livermore, CA USA. Stanley Scott Canc Ctr, Dept Pathol, New Orleans, LA USA. Univ Hosp, Dept Clin Hematol, Nantes, France. RP Avet-Loiseau, H (reprint author), Inst Biol, Unite Cytogenet Hematol, 9 Quai Moncousu, F-44093 Nantes, France. NR 31 TC 39 Z9 41 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1045-2257 J9 GENE CHROMOSOME CANC JI Gene Chromosomes Cancer PD OCT PY 1998 VL 23 IS 2 BP 175 EP 182 DI 10.1002/(SICI)1098-2264(199810)23:2<175::AID-GCC11>3.0.CO;2-N PG 8 WC Oncology; Genetics & Heredity SC Oncology; Genetics & Heredity GA 114XT UT WOS:000075635000011 PM 9739021 ER PT J AU Kouprina, N Campbell, M Graves, J Campbell, E Meincke, L Tesmer, J Grady, DL Doggett, NA Moyzis, RK Deaven, LL Larionov, V AF Kouprina, N Campbell, M Graves, J Campbell, E Meincke, L Tesmer, J Grady, DL Doggett, NA Moyzis, RK Deaven, LL Larionov, V TI Construction of human chromosome 16- and 5-specific circular YAC/BAC libraries by in vivo recombination in yeast (TAR cloning) SO GENOMICS LA English DT Article ID TRANSFORMATION-ASSOCIATED RECOMBINATION; ARTIFICIAL CHROMOSOMES; HUMAN DNA; VECTORS; PROPAGATION; FRAGMENTS; SEGMENTS; SYSTEM AB Transformation-associated recombination (TAR) in yeast was exploited for the selective isolation of human DNAs as large circular yeast artificial chromosomes (YACs) from two rodent/human hybrid cell lines containing human chromosomes 5 and 16. TAR cloning vectors containing the F-factor origin of replication were constructed for use in these experiments. Presence of the F-factor origin in TAR vectors provides the capability of transferring the YACs generated by in vivo recombination in yeast into Escherichia coli cells and propagating them as bacterial artificial chromosomes (BACs). A high enrichment of human versus rodent YACs was observed during isolation of human DNA from the rodent/human hybrid cell lines. Although <3% of the DNA content in the hybrid cells was human, as many as 75% of the transformants contained human YACs. In contrast to the standard YAC cloning method based on in vitro ligation, no human/mouse chimeras were observed during TAR cloning. The constructed human chromosome 16 YAC library had approximately 2.6x coverage, represented by 4320 YAC clones with an average insert size of 80 kb. YAC clones generated from chromosome 16 were successfully converted into BACs by electroporation of DNA isolated from yeast transformants into E. coli. The BAC clones represent similar to 0.6x chromosomal coverage. Pilot YAC and BAC libraries of chromosome 5 have been also constructed. The chromosomal distribution of YAC/BACs from chromosome 5 and chromosome 16 was evaluated by fluorescence in situ hybridization (FISH). The distribution of FISH signals appeared random along the length of each chromosome. We conclude that TAR cloning provides an efficient means for generating representative chromosome-specific YAC/BAC libraries. (C) 1998 Academic Press. C1 NIEHS, Mol Genet Lab, Res Triangle Pk, NC 27709 USA. Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Human Genome Studies, Los Alamos, NM 87545 USA. RP Kouprina, N (reprint author), NIEHS, Mol Genet Lab, Box 12233, Res Triangle Pk, NC 27709 USA. EM kouprina@niehs.nih.gov NR 20 TC 16 Z9 17 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 EI 1089-8646 J9 GENOMICS JI Genomics PD OCT 1 PY 1998 VL 53 IS 1 BP 21 EP 28 DI 10.1006/geno.1998.5469 PG 8 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 131UK UT WOS:000076593500003 PM 9787074 ER PT J AU Curtis, LJ Li, Y Gerbault-Seureau, M Kuick, R Dutrillaux, AM Goubin, G Fawcett, J Cram, S Dutrillaux, B Hanash, S Muleris, M AF Curtis, LJ Li, Y Gerbault-Seureau, M Kuick, R Dutrillaux, AM Goubin, G Fawcett, J Cram, S Dutrillaux, B Hanash, S Muleris, M TI Amplification of DNA sequences from chromosome 19q13.1 in human pancreatic cell lines SO GENOMICS LA English DT Article ID COMPARATIVE GENOMIC HYBRIDIZATION; ZINC-FINGER MOTIFS; K-RAS; COPY NUMBER; ADENOCARCINOMA; CANCER; CARCINOMAS; GENE; ABNORMALITIES; TUMORS AB Conventional cytogenetics and comparative genomic hybridization (CGH) were utilized to identify recurrent chromosomal imbalances in 12 pancreatic adenocarcinoma cell lines. Multiple deletions and gains were observed in all cell lines. Losses affecting chromosomes or chromosome arms 9p, 13, 18q, 8p, 4, and 10p and gains involving chromosome arms or bands 19q13.1, 20q, 5p, 7p, 11q, 3q25-qter, 8q24, and 10q were commonly observed. Interestingly, 19 distinct sites of high-level amplification were found by CGH. Recurrent sites involved 19q13.1 (6 cases), 5p (3 cases), and 12p and 16p (2 cases). Amplification of KRAS2 was demonstrated in 2 cell lines and that of ERBB2 in another. To define the occurrence of chromosome 19 amplification further, two-dimensional analysis of NotI genomic restriction digests and fluorescence in situ hybridization using probes from band 19q13.1 were utilized. High-level amplification of overlapping sets of chromosome 19 NotI fragments was exhibited in 3 cell lines of which 2 showed amplification of both OZF and AKT2 genes and 1 that of AKT2 alone. In these 3 cell lines, amplification of chromosome 19 sequences was associated with the presence of a homogeneously staining region, Our results provide evidence of heterogeneity in. the extent of chromosome 19 amplification and suggest the existence of yet unknown amplified genes that may play a role in pancreatic carcinogenesis. (C) 1998 Academic Press. C1 Inst Curie, CNRS, UMR 147, F-75248 Paris 05, France. Univ Edinburgh, Western Gen Hosp, Mol Med Ctr, Sir Alastair Currie CRC Labs, Edinburgh, Midlothian, Scotland. Univ Michigan, Sch Med, Dept Pediat, Ann Arbor, MI 48109 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Muleris, M (reprint author), Inst Curie, CNRS, UMR 147, 26 Rue Dulm, F-75248 Paris 05, France. NR 41 TC 39 Z9 39 U1 0 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD OCT 1 PY 1998 VL 53 IS 1 BP 42 EP 55 DI 10.1006/geno.1998.5405 PG 14 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 131UK UT WOS:000076593500005 PM 9787076 ER PT J AU Ingram, BL De Deckker, P Chivas, AR Conrad, ME Byrne, AR AF Ingram, BL De Deckker, P Chivas, AR Conrad, ME Byrne, AR TI Stable isotopes, Sr/Ca, and Mg/Ca in biogenic carbonates from Petaluma Marsh, northern California, USA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID SAN-FRANCISCO BAY; RECORD; PALEOSALINITY; SYSTEMATICS; INDICATOR; SALINITY AB Stable isotope (O-18/O-16 and C-13/C-12) and minor-element compositions (Sr/Ca and Mg/Ca ratios) of ostracodes and gastropods separated from marsh sediments from San Francisco Bay, Northern California, were used to reconstruct paleoenvironmental changes in Petaluma Marsh over the past 700 yr. The value of delta(18)O in the marsh carbonates reflects changes in freshwater inflow, evaporation, and temperature. Mg/Ca and Sr/Ca in ostracode calcite reflect changes in both freshwater inflow and temperature, although primarily reflect temperature changes in the salinity range of about 10-35 parts per thousand. Ostracode delta(18)O values show a gradual increase by 5 parts per thousand between 500 yr BP and the present, probably reflecting rising sea level and increased evaporation in the marsh. Superimposed on this trend are higher frequency Mg/Ca and delta(18)O variations (3-4 parts per thousand), probably reflecting changes in freshwater inflow and evaporation. A period of low Mg/Ca occurred between about 100-300 cal yr BP, suggesting wetter and cooler conditions during the Little Ice Age. Higher Mg/Ca ratios occurred 600-700 cal yr BP, indicating drier and warmer conditions during the end of the Medieval Warm Period. Both ostracode and gastropod delta(13)C values decrease up-core, reflecting decomposition of marsh vegetation, which changes from C-4 (delta(13)C similar to -12 parts per thousand) to CAM (delta(13)C = -26 parts per thousand)-type vegetation over time. Copyright (C) 1998 Elsevier Science Ltd. C1 Univ Calif Berkeley, Dept Geol & Geophys, Berkeley, CA 94720 USA. Australian Natl Univ, Dept Geol, Canberra, ACT 0200, Australia. Univ Wollongong, Sch Geosci, Wollongong, NSW 2500, Australia. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Isotope Geochem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Geog, Berkeley, CA 94720 USA. RP Ingram, BL (reprint author), Univ Calif Berkeley, Dept Geol & Geophys, Berkeley, CA 94720 USA. RI Conrad, Mark/G-2767-2010; Chivas, Allan/B-4242-2013; OI Chivas, Allan/0000-0002-1459-6330 NR 22 TC 17 Z9 17 U1 2 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 OCT PY 1998 VL 62 IS 19-20 BP 3229 EP 3237 DI 10.1016/S0016-7037(98)00240-3 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 183PF UT WOS:000079561400004 ER PT J AU Fredrickson, JK Zachara, JM Kennedy, DW Dong, HL Onstott, TC Hinman, NW Li, SM AF Fredrickson, JK Zachara, JM Kennedy, DW Dong, HL Onstott, TC Hinman, NW Li, SM TI Biogenic iron mineralization accompanying the dissimilatory reduction of hydrous ferric oxide by a groundwater bacterium SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID SHEWANELLA-PUTREFACIENS MR-1; ANAEROBIC LAKE-SEDIMENTS; GREEN RUST; ISOTOPIC COMPOSITION; MICROBIAL REDUCTION; DIAGENETIC SIDERITE; MAGNETITE FORMATION; AQUATIC SEDIMENTS; AQUEOUS-SOLUTION; OUTER-MEMBRANE AB Dissimilatory iron-reducing bacteria (DIRB) couple the oxidation of organic matter or H-2 to the reduction of iron oxides. The factors controlling the rate and extent of these reduction reactions and the resulting solid phases are complex and poorly understood. Batch experiments were conducted with amorphous hydrous ferric oxide (HFO) and the DIRE Shewanella putrefaciens, strain CN32, in well-defined aqueous solutions to investigate the reduction of HFO and formation of biogenic Fe(II) minerals. Lactate-HFO solutions buffered with either bicarbonate or 1,4-piperazinediethanesulfonic acid (PIPES) containing various combinations of phosphate and anthraquinone-2,6-disulfonate (AQDS), were inoculated with S. putrefaciens CN32, AQDS, a humic acid analog that can be reduced to dihydroanthraquinone by CN32, was included because of its ability to function as an electron shuttle during microbial iron reduction and as an indicator of pe. Iron reduction was measured with time, and the resulting solids were analyzed by X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDS) and selected area electron diffraction (SAED). In HCO3- buffered medium with AQDS, HFO was rapidly and extensively reduced, and the resulting solids were dominated by ferrous carbonate (siderite). Ferrous phosphate (vivianite) was also present in HCO3- medium containing P, and fine-grained magnetite was present as a minor phase in HCO3- medium with or without P. In the PIPES-buffered medium, the rate and extent of reduction was strongly influenced by AQDS and P. With AQDS, HFO was rapidly converted to highly crystalline magnetite whereas in its absence, magnetite mineralization was slower and the final material less crystalline. In PIPES with both P and AQDS, a green rust type compound [Fe(6-x)Fe-II(x)(II)(OH)(12)](x+)[(A(2-))(x/2) . yH(2)O](x-) was the dominant solid phase formed; in the absence of AQDS a poorly crystalline product was observed. The measured pe and nature of the solids identified were consistent with thermodynamic considerations. The composition of aqueous media in which microbial iron reduction occurred strongly impacted the rate and extent of iron reduction and the nature of the reduced solids. This, in turn, can provide a feedback control mechanism on microbial metabolism. Hence, in sediments where geochemical conditions promote magnetite formation: two-thirds of the Fe(III) will be sequestered in a form that may not be available for anaerobic bacterial respiration. Copyright (C) 1998 Elsevier Science Ltd. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. Univ Montana, Dept Geol, Missoula, MT 59812 USA. RP Fredrickson, JK (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. OI Kennedy, David/0000-0003-0763-501X NR 92 TC 477 Z9 498 U1 52 U2 223 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 OCT PY 1998 VL 62 IS 19-20 BP 3239 EP 3257 DI 10.1016/S0016-7037(98)00243-9 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 183PF UT WOS:000079561400005 ER PT J AU Myneni, SCB Traina, SJ Waychunas, GA Logan, TJ AF Myneni, SCB Traina, SJ Waychunas, GA Logan, TJ TI Experimental and theoretical vibrational spectroscopic evaluation of arsenate coordination in aqueous solutions, solids, and at mineral-water interfaces SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID THALLIUM DIHYDROGEN ARSENATE; SEMIEMPIRICAL METHODS; RAMAN; PARAMETERS; IONS; HYDRATION; COMPLEXES; GOETHITE; OPTIMIZATION; FERRIHYDRITE AB Arsenate (AsO43-) is a common species in oxidizing aquatic systems and hydrothermal fluids, and its solubility and partitioning into different mineral phases are determined by the nature of AsO43- coordination, solution pH, type of soluble cations, and H2O structure at the mineral-fluid interfaces. While the vibrational spectroscopy has been widely used in examining the AsO43- coordination chemistry, insufficient knowledge on the correlation of AsO43- molecular structure and its vibrational spectra impeded the complete spectral interpretation. In this paper, we evaluated the vibrational spectroscopy of AsO43- in solutions, crystals, and sorbed on mineral surfaces using theoretical (semiempirical, for aqueous species) and experimental studies, with emphasis on the protonation, hydration, and metal complexation influence on the As-O symmetric stretching vibrations. Theoretical predictions are in excellent agreement with the experimental studies and helped in the evaluation of vibrational modes of several arsenate-complexes and in the interpretation of experimental spectra. These vibrational spectroscopic studies (IR, Raman) suggest that the symmetry of AsO43- polyhedron is strongly distorted, and its As-O vibrations are affected by protonation and the relative influence on AsO43- structure decreases in the order: H+ >> cation greater than or equal to H2O. For all AsO43- complexes, the As-OX symmetric stretching (X = metal, H+, H2O; less than or equal to 820 cm(-1)) shifted to lower wavenumbers when compared to that of uncomplexed AsO43-. In addition, the As-OH symmetric stretching of protonated arsenates in aqueous solutions shift to higher energies with increasing protonation (<720, <770, <790 cm(-1) for HAsO42-, H2AsO4-, and H2AsO40, respectively). The protonated arsenates in crystalline solids show the same trend with little variation in As-OH symmetric stretching vibrations. Since metal complexation of protonated AsO43- does not influence the As-OH vibrations significantly, deducing symmetry information from their vibrational spectra is difficult. However, for metal unprotonated-AsO43- complexes, the shifts in As-OM (M = metal) vibrations are influenced only by the nature of complexing cation and the type of coordination, and hence the AsO43- coordination environment can be interpreted directly from the splitting of As-O degenerate vibrations and relative shifts in the As-OM modes. This information is critical in evaluating the structure of AsO43- sorption complexes at the solid-water interfaces. The vibrational spectra of other tetrahedral oxoanions are expected to be along similar lines. Copyright (C) 1998 Elsevier Science Ltd. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Ohio State Univ, Sch Nat Resources, Columbus, OH 43210 USA. RP Myneni, SCB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Mail Stop 90-1116, Berkeley, CA 94720 USA. EM smyneni@lbl.gov NR 66 TC 181 Z9 185 U1 1 U2 42 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 OCT PY 1998 VL 62 IS 19-20 BP 3285 EP 3300 DI 10.1016/S0016-7037(98)00222-1 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 183PF UT WOS:000079561400007 ER PT J AU Brenan, JM Ryerson, FJ Shaw, HF AF Brenan, JM Ryerson, FJ Shaw, HF TI The role of aqueous fluids in the slab-to-mantle transfer of boron, beryllium, and lithium during subduction: Experiments and models SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID YOUNG VOLCANIC-ROCKS; MID-ATLANTIC RIDGE; B-BE SYSTEMATICS; OCEANIC-CRUST; EXPERIMENTAL CONSTRAINTS; ION-MICROPROBE; HIGH-PRESSURE; PARTITION-COEFFICIENTS; GEOCHEMICAL VARIATIONS; TRACE-ELEMENTS AB The low atomic mass elements B, Be, and Li are viewed as sensitive tracers of the involvement of subducted materials in the genesis of island are magmas. In order to better assess the role of dense aqueous fluids in the slab-to-mantle transfer of these elements during subduction, measurements have been made of partition coefficients for B, Be, and Li between aqueous fluid and minerals likely to be present in the basaltic portion of the downgoing slab, namely clinopyroxene and garnet. Experiments at 900 degrees C and 2.0 GPa reveal that the average clinopyroxene-fluid partition coefficient for Be (similar to 2) exceeds that for either Li (similar to 0.2) or B (similar to 0.02) and values are 100X (B,Li) to 1000X (Be) larger than partition coefficients for garnet. Clinopyroxene-fluid partition coefficients were found to vary with the alumina content of run-product clinopyroxenes, but this variation is interpreted to reflect the specific exchange reaction that governs the incorporation of these elements into the pyroxene structure, and not mineral-fluid disequilibrium. The element pairs B-Be, B-Nb, and Li-Yb are considered to be essentially unfractionated during the partial melting process, as evidence by their coherent behaviour in apparently cogenetic lavas and the similarity in their measured mineral-melt partition coefficients. A comparison of clinopyroxene-fluid partition coefficients for these elements with clinopyroxene-silicate melt values reveals that B/Be, B/Nb, and Li/Yb ratios will be significantly fractionated in coexisting aqueous fluid with respect to the residual solid. The elevated ratios of B/Be, B/Nb, and Li/Yb in island are lavas relative to MORE are thus considered to be consistent with an origin by fluid-mediated slab-to-mantle transport. A quantitative model of slab dehydration accompanied by progressive water loss and changes in residual mineral mode reveals that source regions with B/Be and B/Nb appropriate for producing the Izu and Kurile IAB suites can be generated using available estimates for the composition of altered oceanic crust, although B abundances at the high end of published values are required. Because the highest values of B/Be and B/Nb are produced in the mantle wedge at relatively shallow depths, some additional process, such as subduction-induced flow of a hydrated mantle wedge, is required in order to transfer enriched material to depths appropriate for the formation of magmas beneath the volcanic front. Calculations indicate that by the time the slab reaches a depth of 200 km, B/Be and B/Nb in the dehydration residue has been reduced to similar to 5-12% of initial values. Thus, the preferential loss of B during dehydration is viewed as a viable mechanism to prevent the excess B acquired during near-surface alteration of oceanic crust from being cycled into the mantle, thereby maintaining the distinction in B/Be and B/Nb for mantle and crustal reservoirs. Copyright (C) 1998 Elsevier Science Ltd. C1 Univ Toronto, Dept Geol, Toronto, ON M5S 3B1, Canada. Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Geosci & Environm Technol Div, Livermore, CA 94551 USA. RP Brenan, JM (reprint author), Univ Toronto, Dept Geol, Toronto, ON M5S 3B1, Canada. EM brenan@zircon.geology.utoronto.ca RI Shaw, Henry/B-6445-2012 OI Shaw, Henry/0000-0003-0681-5430 NR 64 TC 154 Z9 162 U1 2 U2 30 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 OCT PY 1998 VL 62 IS 19-20 BP 3337 EP 3347 DI 10.1016/S0016-7037(98)00224-5 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 183PF UT WOS:000079561400011 ER PT J AU Urrutia, MM Roden, EE Fredrickson, JK Zachara, JM AF Urrutia, MM Roden, EE Fredrickson, JK Zachara, JM TI Microbial and surface chemistry controls on reduction of synthetic Fe(III) oxide minerals by the dissimilatory iron-reducing bacterium Shewanella alga SO GEOMICROBIOLOGY JOURNAL LA English DT Article DE Fe(III) oxide reduction; Fe(III) biosorption; surface saturation; Fe(II) complexation ID ORGANIC-CARBON OXIDATION; POLLUTED AQUIFER VEJEN; FERRIC IRON; AQUATIC SEDIMENTS; MANGANESE; KINETICS; DENMARK; WETLAND; GROWTH AB The role of Fe(ll) biosorption and the effect of medium components on the rare and long-term extent of Fe(lll) oxide reduction (FeRed) by a dissimilatory Fe(lll)-reducing bacterium (Shewanella alga strain BrY) were examined in batch culture experiments. introduction of fresh S. alga cells into month-old cultures in which Fe(III) reduction had ceased resulted in further reduction of synthetic amorphous Fe(lll) oxide, hematite, and two forms of goethite (Gt). Fresh S. alga cells were also able to reduce a substantial amount of synthetic Ct that had been partly or completely saturated with sorbed Fe(ll). Cells that had been precoated with Fe(ll) showed a reduced rate and capacity for FeRed These results indicated that biosorption of Fe(II) had a major impact on FeRed S. alga cells were shown to have an Fe(ll) sorption capacity of similar to 0.1 mmol g(-1), compared with similar to 0.25 mmol g(-1) determined for the synthetic Ct. Sorption experiments with component mixtures indicated that direct interaction between cells and oxide resulted in increased Fe(II)-binding capacity of the mixed system, possibly through production of exopolymeric materials by the cells. Medium constituents that affected Fe(ll) speciation were shown to have a significant indirect influence on the extent of oxide reduction. Malate, which formed soluble complexes with Fe(ll), promoted the extent of oxide reduction. In contrast, high (mM) PO43- concentrations favored surface/bulk precipitation processes which reduced the extent of oxide reduction. Collectively, our results indicate that Fe(ll) sorption by oxide and cell surfaces, together with Fe(ll) complexation by or precipitation with medium components, all influence the rate and extent of FeRed. Furthermore, saturation of sorption cites with Fe(ll) does not appear to limit the ability of S. alga to reduce Fe(lll) oxides, especially if conditions favor growth. C1 Univ Alabama, Dept Sci Biol, Tuscaloosa, AL 35487 USA. Batelle Pacific NW Lab, Richland, WA USA. RP Urrutia, MM (reprint author), Univ Alabama, Dept Sci Biol, Box 870206, Tuscaloosa, AL 35487 USA. NR 47 TC 105 Z9 105 U1 2 U2 31 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-0451 J9 GEOMICROBIOL J JI Geomicrobiol. J. PD OCT-DEC PY 1998 VL 15 IS 4 BP 269 EP 291 PG 23 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 152JM UT WOS:000077774200002 ER PT J AU Forsythe, JH Maurice, PA Hersman, LE AF Forsythe, JH Maurice, PA Hersman, LE TI Attachment of a Pseudomonas sp. to Fe(III)-(hydr)oxide surfaces SO GEOMICROBIOLOGY JOURNAL LA English DT Article DE AFM; bacteria; biofilm; hematite; iron; goethite; Pseudomonas; SPM ID ATOMIC-FORCE MICROSCOPY; HYDROUS FE(III)-OXIDES; DISSOLUTION; BACTERIA; IRON; BIOFILMS; ALUMINUM; MINERALS AB As a first step towards understanding microbial dissolution processes, our research focuses on characterizing attachment features that form between a Pseudomonas sp. bacteria and the Fe(III)-(hydr)oxide minerals hematite and goethite. Microbial growth curves in Fe-limited growth media indicated that the bacteria were able to obtain Fe from the Fe(lll)-(hydr)oxides for use in metabolic processes. A combination of scanning electron microscopy, epifluorescence, and Tapping Mode(TM) atomic-force microscopy showed that the bacteria colonized some fraction of mineralogical aggregates. These aggregates were covered by bacteria and were linked together by relatively open biofilms consisting of networks of fiber-like attachment features intertwined through thin films of amorphous-looking organic material. The biofilm material encompassed numerous individual bacteria, as well as mineralogic particles. We hypothesize that the bacteria first attached to mineral aggregates, perhaps via their flagella, forming colonies. Following initial attachment, the bacteria exuded additional attachment features in the form of fine, branching fibrils intertwined through thin films. The detailed structures of these attachment features were highlighted by Phase Imaging atomic-force microscopy, which served as a real-time contrast enhancement technique and showed some poorly defined sensitivity to different surface materials, most probably related to differences in stiffness or viscoelasticity. Although the mechanism of the microbially enhanced dissolution remains unknown, we hypothesize that the bacteria may have produced micro environments conducive to dissolution through the we of observed extracellular materials. C1 Kent State Univ, Dept Geol, Kent, OH 44242 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM USA. RP Maurice, PA (reprint author), Kent State Univ, Dept Geol, POB 5190, Kent, OH 44242 USA. NR 28 TC 21 Z9 23 U1 3 U2 13 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-0451 J9 GEOMICROBIOL J JI Geomicrobiol. J. PD OCT-DEC PY 1998 VL 15 IS 4 BP 293 EP + PG 19 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 152JM UT WOS:000077774200003 ER PT J AU Onstott, TC Phelps, TJ Colwell, FS Ringelberg, D White, DC Boone, DR McKinley, JP Stevens, TO Long, PE Balkwill, DL Griffin, WT Kieft, T AF Onstott, TC Phelps, TJ Colwell, FS Ringelberg, D White, DC Boone, DR McKinley, JP Stevens, TO Long, PE Balkwill, DL Griffin, WT Kieft, T TI Observations pertaining to the origin and ecology of microorganisms recovered from the deep subsurface of Taylorsville Basin, Virginia SO GEOMICROBIOLOGY JOURNAL LA English DT Article DE deep subsurface; hydrocarbon reservoirs; sulfate reduction; iron reduction; phospholipid fatty acid ID ATLANTIC COASTAL-PLAIN; FE(III)-REDUCING BACTERIA; TERRESTRIAL SUBSURFACE; MICROBIAL BIOMASS; SEDIMENTS; AQUIFERS; OIL; BIOGEOCHEMISTRY; LACUSTRINE; REDUCTION AB To understand the conditions under which microorganisms exist in deep hydrocarbon reservoirs, sidewall cores were collected from a natural gas-bearing formation, 2800 m below the surface in Taylorsville Basin, Virginia. Data from chemical and microbial tracers and controls indicate that the interiors of some sidewall cores contained microorganisms indigenous to the rock formation. The cultured microorganisms were composed primarily of saline-tolerant, thermophilic fermenting, Fe(lll)-reducing, and sulfate-reducing bacteria (I to 10(4) cells/g). The physiological capabilities of the cultured microorganisms are compatible with the temperature (76 degrees C), pressure (32 MPa), and salinity (approximate to 0.8 wt.% NaCl equivalent) in the sampled interval. The petrological data indicated that the strata contain intercrystalline pores of micrometer size, that occur between late diagenetic cement in siltstone and within cross-cutting, mineralized fractures in shale. These pores made up only 0.04% of the rock volume, were mostly gas-filled, and were interconnected by pore throats with diameters <0.04 mu m. Because the pore throats are smaller than known bacteria, the cultured microorganisms were probably trapped within the larger pores containing alkaline, brackish, formation water The total phospholipid fatty acid concentration of the rock samples yielded a cellular concentration equivalent to 4 x 10(5) cells/g, much greater than had been determined by enumeration of the cultured bacteria. This may have resulted from either inhibition of dephosphorolation reactions within pores filled with reduced gases, such as methane, or the inability to culture >0.1% of the viable bacteria. The recovery of living bacteria from such an austere environment represents one of the most remarkable examples of microbial survival yet reported. C1 Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. Oregon Grad Inst Sci & Technol, Portland, OR USA. Battelle Pacific NW Natl Lab, Richland, WA USA. Florida State Univ, Dept Biol Sci, Tallahassee, FL 32306 USA. Golder Associates, Oak Ridge, TN USA. New Mexico Inst Min & Technol, Dept Biol, Socorro, NM 87801 USA. RP Onstott, TC (reprint author), Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. RI phelps, tommy/A-5244-2011; Long, Philip/F-5728-2013 OI Long, Philip/0000-0003-4152-5682 NR 71 TC 54 Z9 58 U1 6 U2 25 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-0451 J9 GEOMICROBIOL J JI Geomicrobiol. J. PD OCT-DEC PY 1998 VL 15 IS 4 BP 353 EP 385 PG 33 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 152JM UT WOS:000077774200007 ER PT J AU Halthore, RN Nemesure, S Schwartz, SE Imre, DG Berk, A Dutton, EG Bergin, MH AF Halthore, RN Nemesure, S Schwartz, SE Imre, DG Berk, A Dutton, EG Bergin, MH TI Models overestimate diffuse clear-sky surface irradiance: A case for excess atmospheric absorption SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RADIATION; BAND AB Radiative transfer models consistently overestimate surface diffuse downward irradiance in cloud-free atmospheres by 9 to 40% at two low altitude sites while correctly calculating direct-normal Solar irradiance. For known systematic and random measurement errors and for realistic aerosol optical properties, the discrepancy can be resolved by a reduction in the vertical aerosol optical thickness (AOT) inferred from sunphotometric measurements by an average 0.02 +/- 0.01 for 32 cases examined, together with a compensating increase in a continuum-like atmospheric absorptance over the solar spectrum of similar to 5.0% +/- 3.0%. This phenomenon is absent at two high altitude sites, where models and measurements agree to within their mutual uncertainties. Examination of apparent AOT at several locations around the globe also indicates presence of such excess atmospheric absorption. The proposed absorption and corresponding reduction in AOT would have important consequences for climate prediction and remote sensing. C1 Brookhaven Natl Lab, Dept Appl Sci, ECD, Upton, NY 11973 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Spectral Sci Inc, Burlington, MA 01803 USA. RP Halthore, RN (reprint author), Brookhaven Natl Lab, Dept Appl Sci, ECD, Bldg 815E, Upton, NY 11973 USA. EM halthore@bnl.gov RI Schwartz, Stephen/C-2729-2008 OI Schwartz, Stephen/0000-0001-6288-310X NR 18 TC 67 Z9 69 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD OCT 1 PY 1998 VL 25 IS 19 BP 3591 EP 3594 DI 10.1029/98GL52809 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 125KJ UT WOS:000076236500013 ER PT J AU Kaiser, DP AF Kaiser, DP TI Analysis of total cloud amount over China, 1951-1994 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MINIMUM TEMPERATURE; SUNSHINE; MAXIMUM; TRENDS AB Trends in Chinese total cloud amount were analyzed for the period 1951-1994. Cloud data were obtained from a database of 6-hourly weather observations provided by the China Meteorological Administration (CMA) to the U.S. Department of Energy's Carbon Dioxide Information Analysis Center (CDIAC) through a bilateral research agreement. Seasonal and annual means of midday (1400 Beijing Time (BT)) and midnight (0200 BT) observations were computed for each of 196 stations and over 8 specific regions of China. Linear regression analysis was used to characterize seasonal and annual trends in total cloud amount from 1951-1994. Decreasing trends in both midday and midnight cloud amount are observed over much of China; most stations in central, eastern, and northeastern China show statistically significant decreases of 1-3% sky cover per decade. These decreases in cloud amount are especially interesting in light of recent temperature trends observed over China. Several studies have shown significant increasing trends in daily minimum temperatures over China since 1951, especially in the northeastern part of the country, precisely where the strongest decreasing trends in total cloud amount are observed. Increases in cloud amount have been offered as a possible explanation for increasing minimum temperatures in other parts of the world; however, in China it seems that some mechanism(s) other than increasing cloud amount must be considered for understanding the observed increase in minimum temperatures. C1 Carbon Dioxide Informat Anal Ctr, Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Kaiser, DP (reprint author), Carbon Dioxide Informat Anal Ctr, Oak Ridge Natl Lab, Div Environm Sci, MS6335, Oak Ridge, TN 37831 USA. NR 11 TC 78 Z9 94 U1 0 U2 6 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 OCT 1 PY 1998 VL 25 IS 19 BP 3599 EP 3602 DI 10.1029/98GL52784 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 125KJ UT WOS:000076236500015 ER PT J AU Zuelsdorf, RS Strangeway, RJ Russell, CT Franz, R AF Zuelsdorf, RS Strangeway, RJ Russell, CT Franz, R TI Trans-ionospheric pulse pairs (TIPPs): Their occurrence rates and diurnal variation SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Trans-Ionospheric Pulse Pairs (TIPPs) have been detected by the Blackbeard instrument aboard the ALEXIS spacecraft in the VHF band between 28 and 166 MHz with dispersion indicating a subionospheric source. Using a database that runs from 2 November 1993 to 19 November 1996, the rate and diurnal variation of TIPP detection are calculated for central Africa, Indonesia, and North America. The rate of TIPP detection by Blackbeard in the frequency band from 28 - 95 MHz is 0.02 and 0.04 TIPPs per second for central Africa and Indonesia respectively. For North America the data were acquired in a narrow band from 28 - 37.9 MHz and the TIPP detection rate is 0.007 events per second. The diurnal variation of TIPPs resembles the diurnal variation of CG lightning during daylight hours. However the TIPP production remains strong through midnight and into the morning hours, whereas CG flash production tends to decrease more sharply after peaking around 4 PM local time. Thus the diurnal variation suggests that TIPPs are not produced in CG flashes, a conclusion consistent with their correlation with intracloud pulses. C1 Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Zuelsdorf, RS (reprint author), Univ Calif Los Angeles, Inst Geophys & Planetary Phys, 3845 Slichter Hall, Los Angeles, CA 90095 USA. OI Russell, Christopher/0000-0003-1639-8298 NR 10 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD OCT 1 PY 1998 VL 25 IS 19 BP 3709 EP 3712 DI 10.1029/98GL02800 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 125KJ UT WOS:000076236500043 ER PT J AU Chang, SW Scudder, JD Fuselier, SA Fennell, JF Trattner, KJ Pickett, JS Spence, HE Menietti, JD Peterson, WK Lepping, RP Friedel, R AF Chang, SW Scudder, JD Fuselier, SA Fennell, JF Trattner, KJ Pickett, JS Spence, HE Menietti, JD Peterson, WK Lepping, RP Friedel, R TI Cusp energetic ions: A bow shock source SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SUPRATHERMAL IONS; PLASMA INSTRUMENT; UPSTREAM; SPACECRAFT; DIFFUSE; EVENTS; WIND; ACCELERATION; MISSION; WAVES AB Recent interpretations of cusp energetic ions observed by the POLAR spacecraft have suggested a new energization process in the cusp [Chen et al., 1997; 1998]. Simultaneous enhancement of H+, He+2, and O>+2 fluxes indicates that they are of solar wind origin. In the present study, we examine H+ and He+2 energy spectra from 20 eV to several 100 keV measured by the Hydra, Toroidal Imaging Mass-Angle Spectrograph (TIMAS), and Charge and Mass Magnetospheric Ion Composition Experiment (CAM-MICE) on POLAR. The combined spectrum for each species is shown to be continuous with a thermal distribution below 10 keV/e and an energetic component above 20 keV/e. Energetic ions with comparable fluxes and a similar spectral shape are commonly observed downstream from the Earth's quasi-parallel (Q(parallel to)) bow Shock. In addition to the similarity in the ion spectra, electric and magnetic field noise and turbulence detected in the cusp by the Plasma Wave Instrument (PWI) and Magnetic Field Experiment (MFE) onboard POLAR are similar to the previously reported observations at the bow shock. The waves appear to be coincidental to the cusp energetic ions rather than causal. We suggest that these ions are not accelerated locally in the cusp. Rather, they are accelerated at the Q(parallel to) bow shock and enter the cusp along open magnetic field lines connecting both regions. C1 Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Aerospace Corp, Los Angeles, CA 90009 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Lockheed Martin Adv Technol Ctr, Dept H1 11, Palo Alto, CA 94304 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Boston Univ, Dept Space Phys & Astron, Ctr Space Phys, Boston, MA 02215 USA. RP Chang, SW (reprint author), Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. RI Friedel, Reiner/D-1410-2012; Scudder, Jack/D-8417-2013; Spence, Harlan/A-1942-2011; Peterson, WK/A-8706-2009; OI Friedel, Reiner/0000-0002-5228-0281; Scudder, Jack/0000-0001-7975-5630; Peterson, WK/0000-0002-1513-6096; Spence, Harlan/0000-0002-2526-2205 NR 22 TC 46 Z9 46 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 OCT 1 PY 1998 VL 25 IS 19 BP 3729 EP 3732 DI 10.1029/98GL52808 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 125KJ UT WOS:000076236500048 ER PT J AU Henderson, MG Reeves, GD Murphree, JS AF Henderson, MG Reeves, GD Murphree, JS TI Are north-south aligned auroral structures an ionospheric manifestation of bursty bulk flows? SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PLASMA SHEET; MIDNIGHT AB Bursty Bulk Flow (BBF) events are an important means of plasma transport in the Earth's magnetotail during substorms. While several studies have been performed using in-situ plasma and field data to determine the characteristics of BBFs, remarkably little attention has been paid to the question of whether or not these events also manifest themselves in the auroral ionosphere. In this paper, we present observations from the Viking UV imager, and the Los Alamos National Laboratory geosynchronous energetic particle detectors that strongly suggest that the north-south aligned structures formed impulsively and repetitively during the expansion phase of substorms may be an ionospheric manifestation of BBFs. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calgary, Dept Phys & Astron, Calgary, AB T2N 1N4, Canada. RP Henderson, MG (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop D-436, Los Alamos, NM 87545 USA. RI Reeves, Geoffrey/E-8101-2011; Henderson, Michael/A-3948-2011 OI Reeves, Geoffrey/0000-0002-7985-8098; Henderson, Michael/0000-0003-4975-9029 NR 14 TC 136 Z9 136 U1 2 U2 7 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 OCT 1 PY 1998 VL 25 IS 19 BP 3737 EP 3740 DI 10.1029/98GL02692 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 125KJ UT WOS:000076236500050 ER PT J AU Weart, WD Rempe, IT Powers, W AF Weart, WD Rempe, IT Powers, W TI The waste isolation pilot plant SO GEOTIMES LA English DT Article C1 Sandia Natl Labs, Org 6000, MS0771, Albuquerque, NM 87185 USA. RP Weart, WD (reprint author), Sandia Natl Labs, Org 6000, MS0771, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 5 Z9 5 U1 1 U2 1 PU AMER GEOLOGICAL INST PI ALEXANDRIA PA 4220 KING ST, ALEXANDRIA, VA 22302-1507 USA SN 0016-8556 J9 GEOTIMES JI Geotimes PD OCT PY 1998 VL 43 IS 10 BP 14 EP 19 PG 6 WC Geosciences, Multidisciplinary SC Geology GA 126DF UT WOS:000076277100015 ER PT J AU Sparks, RB Siegel, JA Wahl, RL AF Sparks, RB Siegel, JA Wahl, RL TI The need for better methods to determine release criteria for patients administered radioactive material SO HEALTH PHYSICS LA English DT Article DE modeling, dose assessment; medical radiation; I-131; regulations ID B-CELL LYMPHOMA; RADIOIMMUNOTHERAPY; I-131 AB In current NRC regulations, three options exist that may be used to determine release criteria for patients administered radioactive materials, Absorbed dose estimates may be based on administered activity, measured dose rate, or on patient-specific calculations. All of these methods proposed by the NRC can lead to overestimation of the dose equivalent to others due to their oversimplified nature. The primary oversimplifications are the use of a point source methodology and using the measured surface entrance dose rate to determine whole body dose. In order to show the inaccuracy of these oversimplifications for I-131, results using Monte Carlo radiation transport analysis with simplified anthropomorphic mathematical phantoms were determined. These results were then compared to actual patient measurements and the results of point source analysis. The measurement data were taken from 49 I-131 radioimmunotherapy patients. The point source calculations were performed using well established methodologies and using the same assumptions as in the NRC regulations for patient release criteria. Monte Carlo results were obtained by implementing two simplified 70 kg anthropomorphic phantoms and performing radiation transport simulation. The activity in the "patient" phantom was assumed to be localized in the abdominal region to correspond to the activity localization seen in the radioimmunotherapy patients who were measured. Dose equivalents per unit cumulated activities were determined for I-131 using the various methods. The relationship between measured dose equivalent per unit cumulated activity and whole body dose equivalent per unit cumulated activity was also investigated using Monte Carlo analysis. The point source method as implemented by the NRC yields an estimated dose equivalent per unit cumulated activity of 1.6 x 10(-8) mSv MBq(-1) s(-1) at 1 m (2.2 x 10(-4) rem mCi(-1) h(-1) at 1 m), and the Monte Carlo based method yielded a whole body dose equivalent per unit cumulated activity in the target phantom of 6.8 x 10(-9) mSv MBq(-1) s(-1)(9.0 x 10(-5) rem mCi(-1) h(-1)) for abdominal localization of activity in the source phantom. The measurements of the radioimmunotherapy patients yielded an average result of 1.0 x 10(-8) mSv MBq(-1) s(-1) (1.3 x 10(-4) rem mCi(-1) h(-1)). When corrected for the difference between measured surface dose equivalent and whole body dose equivalent as determined by Monte Carlo analysis, these measurements represent a whole body dose equivalent per unit cumulated activity of about 6.2 x 10(-9) mSv MBq(-1) s(-1) (8.1 x 10(-5) rem mCi(-1) h(-1)). Based on these results, the current NRC dose-based methodology for the release of patients administered radioactive materials significantly overestimates the dose equivalent to others from I-131 therapy patients. C1 Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. Nucl Phys Enterprises, Voorhees, NJ 08043 USA. Univ Michigan, Med Ctr, Ann Arbor, MI 48103 USA. CDE Inc, Knoxville, TN 37931 USA. FU NCI NIH HHS [CA56794] NR 7 TC 22 Z9 22 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD OCT PY 1998 VL 75 IS 4 BP 385 EP 388 DI 10.1097/00004032-199810000-00004 PG 4 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 124VR UT WOS:000076203800006 PM 9753361 ER PT J AU Lam, NP Neumann, AU Dahari, H Gretch, DR Wiley, TE Perelson, AS Layden, TJ AF Lam, NP Neumann, AU Dahari, H Gretch, DR Wiley, TE Perelson, AS Layden, TJ TI Early viral decline slopes during daily high dose interferon (IFN) are predictive markers of subsequent virologic response. SO HEPATOLOGY LA English DT Meeting Abstract C1 Bar Ilan Univ, IL-52100 Ramat Gan, Israel. Univ Illinois, Dept Pharm Practice, Chicago, IL 60680 USA. Univ Illinois, Dept Med, Chicago, IL 60680 USA. Univ Washington, Seattle, WA 98195 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0270-9139 J9 HEPATOLOGY JI Hepatology PD OCT PY 1998 VL 28 IS 4 SU S MA 940 BP 397A EP 397A PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 125VQ UT WOS:000076258100939 ER PT J AU Stalgis, C McHutchison, J Bekkering, F Perelson, AS AF Stalgis, C McHutchison, J Bekkering, F Perelson, AS TI Prediction of early viral clearance with daily IFN+RIB using a mathematical model. SO HEPATOLOGY LA English DT Meeting Abstract C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Erasmus Univ, Hosp Dijkzigt, NL-3015 GD Rotterdam, Netherlands. Scripps Clin, La Jolla, CA USA. Schering Plough Corp, Res Inst, Kenilworth, NJ 07033 USA. NR 0 TC 4 Z9 4 U1 1 U2 1 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 OCT PY 1998 VL 28 IS 4 SU S MA 941 BP 398A EP 398A PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 125VQ UT WOS:000076258100940 ER PT J AU Rosen, HR Wolf, SL Perelson, AS Blake, M Mittler, J Chung, M Gretch, DR AF Rosen, HR Wolf, SL Perelson, AS Blake, M Mittler, J Chung, M Gretch, DR TI HCV viral kinetics analysis of daily vs BID induction interferon in genotype 1 infection SO HEPATOLOGY LA English DT Meeting Abstract C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Oregon Hlth Sci Univ, VAMC, Portland, OR 97201 USA. Univ Washington, Div Virol, Seattle, WA 98195 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0270-9139 J9 HEPATOLOGY JI Hepatology PD OCT PY 1998 VL 28 IS 4 SU S MA 1253 BP 476A EP 476A PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 125VQ UT WOS:000076258101252 ER PT J AU Zhu, LY Zhu, SJ Li, M Hamilton, JH Ramayya, AV Babu, BRS Ma, WC Rasmussen, JO Stoyer, MA Lee, IY AF Zhu, LY Zhu, SJ Li, M Hamilton, JH Ramayya, AV Babu, BRS Ma, WC Rasmussen, JO Stoyer, MA Lee, IY TI Octupole deformation in neutron-rich Ce-144,Ce-146 nuclei SO HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS-CHINESE EDITION LA Chinese DT Article DE spontaneous fission; high spin states; octupole deformation AB The high spin states and octupole deformation collective bands of neutron-rich nuclei Ce-144,Ce-146 have been established through measuring the prompt gamma-rays from spontaneous fission of Cf-252.;;The highest spin state is up to 15(-). The characteristics of octupole deformation for the two nuclei are discussed. C1 Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. Mississippi State Univ, Dept Phys, Mississippi State, MS 39762 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Zhu, LY (reprint author), Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. NR 8 TC 19 Z9 19 U1 0 U2 0 PU SCIENCE PRESS PI BEIJING PA 16 DONGHUANGCHENGGEN NORTH ST, BEIJING 100717, PEOPLES R CHINA SN 0254-3052 J9 HIGH ENERG PHYS NUC JI High Energy Phys. Nucl. Phys.-Chin. Ed. PD OCT PY 1998 VL 22 IS 10 BP 885 EP 890 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 144BG UT WOS:000077292600004 ER PT J AU Greenham, J Adams, M Doggett, N Mole, S AF Greenham, J Adams, M Doggett, N Mole, S TI Elucidation of the exon-intron structure and size of the human protein kinase C beta gene (PRKCB) SO HUMAN GENETICS LA English DT Article ID NUCLEOTIDE-SEQUENCE; HUMAN CHROMOSOME-16; PHYSICAL MAP; DIVERSITY; MULTIPLE; REGION AB As part of a transcriptional mapping project on human chromosome 16p12, a genomic contig was constructed that spanned the alternatively spliced human protein kinase C beta gene (PRKCB). PRKCB was determined to consist of 18 exons covering approximately 375 kb, with a particularly large intron of over 150 kb between exons 2 and 3. PRKCB is nearly 19 times larger than the highly homologous Drosophila melanogaster protein kinase C gene (dPKC), which has a similar-sized open reading frame but only 13 exons. This increase in size has occurred mostly as a result of expansion of introns, with intron size in the human gene averaging 22 kb compared with 1.5 kb in dPKC. The difference in gene size correlates with the difference in genome size, with the human haploid genome being nearly 18 times larger than the 170-Mb Drosophila haploid genome. C1 Univ Coll & Middlesex Sch Med, Rayne Inst, Dept Pediat, London WC1E 6JJ, England. Inst Genome Res, Rockville, MD 20850 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Human Genome Studies, Los Alamos, NM 87545 USA. RP Mole, S (reprint author), Univ Coll & Middlesex Sch Med, Rayne Inst, Dept Pediat, 5 Univ St, London WC1E 6JJ, England. RI Mole, Sara/C-2024-2008; OI Mole, Sara/0000-0003-4385-4957 NR 16 TC 4 Z9 7 U1 0 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0340-6717 J9 HUM GENET JI Hum. Genet. PD OCT PY 1998 VL 103 IS 4 BP 483 EP 487 DI 10.1007/s004390050854 PG 5 WC Genetics & Heredity SC Genetics & Heredity GA 144DA UT WOS:000077297400019 PM 9856494 ER PT J AU Nicholson, JW Rudolph, W Hager, G AF Nicholson, JW Rudolph, W Hager, G TI Synchronization of dual-line lasing and subsequent gigahertz modulation of iodine lasers through mode locking SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article ID DYNAMICS AB Dual hyperfine line lasing of a Zeeman-tuned photolytic iodine laser resulting in 14-GHz modulated laser radiation was studied experimentally and theoretically as a function of the applied magnetic field. Synchronization of the phases of the two hyperfine Lines necessary for optimum gigahertz modulation was achieved by mode locking. The resulting pulse durations of 740 ps were shorter than those previously observed without a magnetic field. Short pulses, together with the possibility of scaling the results to high-power chemical-oxygen iodine lasers, make this concept attractive for a laser-driven ultrawideband microwave source. C1 Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Nicholson, JW (reprint author), Los Alamos Natl Lab, MS C920, Los Alamos, NM 87545 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 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 OCT PY 1998 VL 34 IS 10 BP 1830 EP 1834 DI 10.1109/3.720214 PG 5 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 121TB UT WOS:000076029100006 ER PT J AU Lei, G Anderson, JE Buchwald, MI Edwards, BC Epstein, RI Murtagh, MT Sigel, GH AF Lei, G Anderson, JE Buchwald, MI Edwards, BC Epstein, RI Murtagh, MT Sigel, GH TI Spectroscopic evaluation of Yb3+-doped glasses for optical refrigeration SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE laser cooling; optical properties of solids; optical refrigeration; rare-earth doped glasses ID BOSE-EINSTEIN CONDENSATION; CROSS-SECTION; LASER; EMISSION; ATOMS AB The absorption and emission properties of Yb3+- doped ZBLANP, BIGaZYT and QX/Yb phosphate glasses are studied to evaluate their potential for laser-induced fluorescent cooling or optical refrigeration. The efficiency of optical refrigeration increases with pump wavelength in the anti-Stokes region. The cooling efficiencies of the three glasses as a function of temperature are evaluated at the wavelength lambda(p) corresponding to the absorption coefficient of 10(-3) cm(-1). For temperatures <110 K, the cooling efficiency of the BIGaZYT glass may be more than twice that of the ZBLANP. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Buchwald Consulting, Santa Fe, NM 87501 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. RP Lei, G (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 26 TC 45 Z9 46 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD OCT PY 1998 VL 34 IS 10 BP 1839 EP 1845 DI 10.1109/3.720216 PG 7 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 121TB UT WOS:000076029100008 ER PT J AU Bibeau, C Beach, RJ Mitchell, SC Emanuel, MA Skidmore, J Ebbers, CA Sutton, SB Jancaitis, KS AF Bibeau, C Beach, RJ Mitchell, SC Emanuel, MA Skidmore, J Ebbers, CA Sutton, SB Jancaitis, KS TI High-average-power 1-mu m performance and frequency conversion of a diode-end-pumped Yb : YAG laser SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE CW lasers; diodes; frequency conversion; lasers; Q-switched lasers; Yb : YAG; ytterbium ID SOLID-STATE LASER; ARRAYS AB Using a diode-end-pumped technology, a Yb:YAG laser capable of delivering up to 434 W of CW power has been demonstrated. The system incorporates a unique composite rod design which allows for high-average-power operation while simultaneously suppressing parasitic oscillations, Modeling and experimental data to support the quenching of parasitics are discussed. Beam quality measurements for CW operation with several cavity configurations are presented. In particular, beam quality measurements at 340-W CW yielded a beam quality factor of M-2 = 21. Predictions of a quasi-three-level model are compared with the experimental data for several output coupler reflectivities. An observed dependence of the cavity mode fill as a function of output coupler reflectivity is discussed. Employing a single acoustooptical switch, the system was Q-switched at 10 kHz and generated output powers up to 280 W with a measured beam quality of M-2 = 6.8 at 212 W. With an external dual-KTP crystal configuration, the Q-switched output was frequency converted to 515 nm and produced up to 76 W at 10 kHz in a 30-ns pulse length. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Bibeau, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 25 TC 81 Z9 88 U1 2 U2 10 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 OCT PY 1998 VL 34 IS 10 BP 2010 EP 2019 DI 10.1109/3.720241 PG 10 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 121TB UT WOS:000076029100033 ER PT J AU Reinovsky, RE Turchi, PJ AF Reinovsky, RE Turchi, PJ TI Special issue on pulsed power science and technology - Guest editorial SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Editorial Material C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Ohio State Univ, Columbus, OH 43210 USA. RP Reinovsky, RE (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 OCT PY 1998 VL 26 IS 5 BP 1366 EP 1367 DI 10.1109/TPS.1998.736018 PG 2 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400001 ER PT J AU Loubriel, GM Zutavern, FJ Mar, A Hjalmarson, HP Baca, AG O'Malley, MW Helgeson, WD Falk, RA Brown, DJ AF Loubriel, GM Zutavern, FJ Mar, A Hjalmarson, HP Baca, AG O'Malley, MW Helgeson, WD Falk, RA Brown, DJ TI Longevity of optically activated, high gain GaAs photoconductive semiconductor switches SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE high speed circuits/devices; optoelectronic devices; photoconductive materials/devices; pulse power systems AB The longevity of high gain GaAs photoconductive semiconductor switches (PCSS's) has been extended to well over ten million pulses by reducing the density of carriers at the semiconductor to metal interface. This was achieved by reducing the density in the vertical and lateral directions. The latter was achieved by varying the spatial distribution of the trigger light thereby widening the current filaments that are characteristic of the high gain switches. We reduced the carrier density in the vertical direction by using ion implantation. These results were obtained for; currents of about 10 A, current duration of 3.5 ns, and switched voltage of similar to 2 kV, At currents of similar to 70 A, the switches last for 0.6 million pulses. In order to improve the performance at high currents, new processes such as deep diffusion and epitaxial growth of contacts are being pursued. To guide this effort we recorded open shutter, infra-red images, and time-resolved Schlieren images of the current filaments, which form during high gain switching. We measured, under varying conditions, a carrier (electrons or holes) density that ranges from 3 x 10(17) cm(-3) to 6 x 10(18) cm(-3). C1 OptoMetrix Inc, Renton, WA 98058 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Loubriel, GM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 18 Z9 28 U1 3 U2 5 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 OCT PY 1998 VL 26 IS 5 BP 1393 EP 1402 DI 10.1109/27.736024 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400003 ER PT J AU Bowers, RL Brownell, JH Greene, AE Peterson, DL Roderick, NF Turchi, PJ AF Bowers, RL Brownell, JH Greene, AE Peterson, DL Roderick, NF Turchi, PJ TI Effects of plasma surface layers on the efficiency of plasma flow switching SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE computational simulation; magnetohydrodynamics; switching ID Z-PINCHES AB The plasma flow switch is a possible fast opening-switch for Z-pinches on inductive-store pulsed-power machines. This paper presents results of two-dimensional, radiation-magnetohydrodynamic models for a well-characterized plasma flow switch operating into a load region at current levels of 5-6 MA. The calculations predict that motion of the switch plasma along coaxial electrodes leads to the formation along the inner electrode of a boundary layer that can interfere with switching. The simulations describe the effect of the boundary layer on switching and show that it may be removed by means of a boundary-layer trap. Predictive calculations were used to eliminate the effects of the boundary layer and led to an improvement in the switch's performance. Comparison with experiments lends credence to the model. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. Ohio State Univ, Dept Aerosp Engn Appl Mech & Aviat, Columbus, OH 43210 USA. RP Bowers, RL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 17 TC 3 Z9 3 U1 0 U2 0 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 OCT PY 1998 VL 26 IS 5 BP 1420 EP 1436 DI 10.1109/27.736030 PG 17 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400006 ER PT J AU Degnan, JH Kiuttu, GF Turchi, PJ Graham, JD Goforth, JH Lopez, EA Oona, H Tasker, DG AF Degnan, JH Kiuttu, GF Turchi, PJ Graham, JD Goforth, JH Lopez, EA Oona, H Tasker, DG TI High voltage pulses for high impedance loads using explosive formed fuses SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE explosive formed fuses; explosive magnetic flux compression; high impedance loads; high voltage pulses; inductive stores AB Explosive formed fuses (EFF's) use conducting elements that are deformed by explosive pressure (typically, against dielectric dies), This causes the fuse geometry to change, so that the conducting element cross section decreases, This enables a higher ratio of current conduction to current interrupt time than for normal fuses, and it enables more control of when current interruption occurs. In combination,vith a suitable output closing switch, EFF's can be used to obtain several hundred kilovolt voltage pulses from inductive stores to drive several ohm loads, With proper choices of inductive store, EFF geometry and material, and output closing switch features, such a voltage pulse can be approximately flat topped for microsecond duration and have a small fraction of microsecond risetime, We present theoretical analysis and circuit simulations which illustrate this, using scaled empirical EFF parameters for inductive stores in the I weber flux, several hundred nanohenry range. The circuit simulations were done using MicroCap-IV, with user defined elements. These simulations were done with static inductive stores and with explosive magnetic flux compression generators driving inductive stores. C1 USAF, Res Labs, DEHP, Kirtland AFB, NM 87117 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Degnan, JH (reprint author), USAF, Res Labs, DEHP, Phillips Res Site, Kirtland AFB, NM 87117 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 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 OCT PY 1998 VL 26 IS 5 BP 1437 EP 1443 DI 10.1109/27.736034 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400007 ER PT J AU Reinovsky, RE Atchison, WL Goforth, JH Lindemuth, IR Lopez, EA Marsh, SP AF Reinovsky, RE Atchison, WL Goforth, JH Lindemuth, IR Lopez, EA Marsh, SP TI Caballero: A high current flux compressor system for 100 MJ solid liner experiments SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE disk explosive flux compressor; flux compression generators; high explosive pulsed power; imploding liners; solid liners AB Pulse power systems delivering in excess of 100 MJ represent one of the next major challenges to the community. While laboratory pulse power systems in this energy range are feasible, they represent very substantial investments of both time and resources. Prudence requires that fundamental proof of principle for the contemplated application be established before such massive resources are committed. Explosive pulse power systems using magnetic flux compression provide a direct path to such demonstrations. Furthermore, as energy requirements grow, they may represent the only affordable source of ultrahigh energy environments. In this paper we report the results of an experimental test of a first generation disk generator system. Individual disk segments have been tested with framing camera diagnostics to evaluate overall performance dynamics and material, and fabrication failure points. In general no bulk failures were observed in several shots and the critical weld joints were seen to maintain integrity for at least 4 mu s after arrival of the detonation front. Single module pulse power experiments have been conducted at reduced initial current (1.5-2.0 MA) with a fixed inductance load of 0.22 nH. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Reinovsky, RE (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 6 TC 2 Z9 2 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD OCT PY 1998 VL 26 IS 5 BP 1454 EP 1462 DI 10.1109/27.736040 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400009 ER PT J AU McGrath, RT Veerasingam, R Hunter, JA Rockett, PD Campbell, RB AF McGrath, RT Veerasingam, R Hunter, JA Rockett, PD Campbell, RB TI Measurements and simulations of VUV emissions from plasma flat panel display pixel microdischarges SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE micro discharge; micro pixel; plasma flat panel display; vacuum ultra-violet (VUV) emission AB This paper reports on measurements of the principal vacuum ultra-violet emission lines from micro discharges operating with helium/xenon gas mixture used in full color plasma driven pat panel display pixels. The principal emission lines observed are the 147 and 129 nm lines from atomic xenon transitions and the relatively broad emissions from xenon dimers centered near 173 nm. We report on the changing intensities of these lines with variation in xenon concentration in the pixel gas mixtures, which affect the overall luminous efficiency of the display. A one-dimensional computer model has been used to simulate the discharge evolution. The model tracks the populations of twelve different representative quantum energy levels of the helium and xenon atoms, as well as the production and decay of the xenon dimers. The atomic physics description is sufficiently detailed to allow prediction of the relative intensities of the dominant emission lines. We find that model predicted intensities for xenon atomic and dimer emission lines agree well with experimental measurements. C1 Penn State Univ, University Pk, PA 16802 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP McGrath, RT (reprint author), Penn State Univ, University Pk, PA 16802 USA. EM mcgrath@engr.psu.edu NR 35 TC 20 Z9 24 U1 0 U2 0 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 OCT PY 1998 VL 26 IS 5 BP 1532 EP 1542 DI 10.1109/27.736057 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400019 ER PT J AU Oks, EM Brown, IG AF Oks, EM Brown, IG TI Electron beam extraction from a broad-beam vacuum-arc metal plasma source SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE electron beams; electron gun; ion source; metal plasma; plasma source; vacuum arc ID HOLLOW-CATHODE DISCHARGE; ION SOURCES AB We describe experiments demonstrating the formation of a high current electron beam from a vacuum are plasma. A preexisting vacuum are ion source was used, with the extraction voltage reversed in polarity so as to form an electron beam rather than an ion beam; no other changes were required. The beam formed was of energy up to 33 keV, beam current up to 70 A, beam diameter about 10 cm, pulse width 500 mu s, and energy density up to 25 J/cm(2). This kind of source can be used for material surface modification. C1 Russian Acad Sci, Inst High Current Elect, Tomsk 634050, Russia. State Univ Control Syst & Radioelect, Tomsk 634050, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Oks, EM (reprint author), Russian Acad Sci, Inst High Current Elect, Tomsk 634050, Russia. RI Oks, Efim/A-9409-2014 OI Oks, Efim/0000-0002-9323-0686 NR 16 TC 6 Z9 7 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD OCT PY 1998 VL 26 IS 5 BP 1562 EP 1565 DI 10.1109/27.736062 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400022 ER PT J AU Symbalisty, EMD Roussel-Dupre, RA Yukhimuk, VA AF Symbalisty, EMD Roussel-Dupre, RA Yukhimuk, VA TI Finite volume solution of the relativistic Boltzmann equation for electron avalanche studies SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE Boltzmann equation; electron avalanche; finite volume; relativistic ID RUNAWAY AIR-BREAKDOWN; THUNDERCLOUD FIELDS; DISCHARGES AB The Boltzmann equation for a population of relativistic electrons in a constant external electric field in air is solved numerically in order to determine parameters of the resulting runaway electron beam. The numerical solution takes advantage of algorithms from computational fluid dynamics. This work revises the results from the original work where the numerical solution was found to be unstable. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Symbalisty, EMD (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 47 Z9 48 U1 1 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 OCT PY 1998 VL 26 IS 5 BP 1575 EP 1582 DI 10.1109/27.736065 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 147EM UT WOS:000077475400024 ER PT J AU Hsu, JS AF Hsu, JS TI Instantaneous phasor method for obtaining instantaneous balanced fundamental components for power quality control and continuous diagnostics SO IEEE TRANSACTIONS ON POWER DELIVERY LA English DT Article DE method; instantaneous phasors; balanced fundamental component; power quality; control; continuous diagnostics AB A new instantaneous phasor method for obtaining instantaneous balanced fundamental components is introduced. An example is presented. This technique may be used for active power quality control and for continuous diagnostics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hsu, JS (reprint author), Oak Ridge Natl Lab, POB 2009,MS 8058, Oak Ridge, TN 37831 USA. NR 14 TC 18 Z9 20 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 0885-8977 J9 IEEE T POWER DELIVER JI IEEE Trans. Power Deliv. PD OCT PY 1998 VL 13 IS 4 BP 1494 EP 1500 DI 10.1109/61.714826 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 122XG UT WOS:000076096300076 ER PT J AU Seshadri, KS Shamsi, A AF Seshadri, KS Shamsi, A TI Effects of temperature, pressure, and carrier gas on the cracking of coal tar over a char-dolomite mixture and calcined dolomite in a fixed-bed reactor SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article AB A distillation fraction of a coal-derived liquid (tar) was cracked over a char-dolomite mixture, calcined dolomite, and silicon carbide in a fixed-bed reactor. The char-dolomite mixture (FWC) was produced from Pittsburgh No. 8 coal and dolomite in a Foster Wheeler carbonizer. The experiments were conducted under nitrogen and simulated coal gas (SCG), which was a mixture of CO, CO2, H2S, CH4, N-2, and steam, at 1 and 17 atm. The conversion over these materials under nitrogen was much higher at 17 atm than at 1 atm. At higher pressures, tar molecules were trapped in the pores of the bed material and underwent secondary reactions, resulting in the formation of excess char. However, when nitrogen was replaced by SCG, the reactions that induce char formation were suppressed, thus increasing the yield of gaseous products. The analysis of the gaseous products and the spent bed materials for organic and inorganic carbons suggested that the product distribution can be altered by changing the carrier gas, temperature, and pressure. C1 EG&G Tech Serc W Virginia Inc, Morgantown, WV 26507 USA. US DOE, Fed Energy Technol Ctr, Morgantown, WV 26507 USA. RP Seshadri, KS (reprint author), EG&G Tech Serc W Virginia Inc, POB 880,3610 Collins Ferry Rd, Morgantown, WV 26507 USA. NR 13 TC 19 Z9 27 U1 3 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD OCT PY 1998 VL 37 IS 10 BP 3830 EP 3837 DI 10.1021/ie980190a PG 8 WC Engineering, Chemical SC Engineering GA 127UX UT WOS:000076369900006 ER PT J AU Gasper-Galvin, LD Atimtay, AT Gupta, RP AF Gasper-Galvin, LD Atimtay, AT Gupta, RP TI Zeolite-supported metal oxide sorbents for hot-gas desulfurization SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID HIGH-TEMPERATURE DESULFURIZATION; FUEL GASES; HYDROGEN-SULFIDE; ZINC TITANATE; COAL-GAS; REMOVAL; SULFUR; H2S; MNO/GAMMA-AL2O3; REGENERATION AB This paper describes the results of the development of supported mixed-metal oxide sorbents for hot-gas desulfurization capable of withstanding multiple sulfidation/regeneration cycles at 871 degrees C (1600 degrees F). The sorbents consisted of various combinations of copper, molybdenum, and/or manganese oxides supported on a high silica-containing zeolite. These sorbents were tested in a fixed-bed reactor with simulated coal gas at 205 kPa (15 psig). The combination of all three metal oxides displayed synergism in enhancing efficiency for H2S removal and improved the crush strength on the pellets. Copper oxide was the most active component for reaction with H2S, while molybdenum and manganese oxides appeared to act as catalysts/promoters. During multicycle testing, this ternary metal oxide sorbent retained its reactivity and mechanical strength. C1 US DOE, Fed Energy Technol Ctr, Morgantown, WV 26507 USA. Middle E Tech Univ, Dept Environm Engn, TR-06531 Ankara, Turkey. Res Triangle Inst, Res Triangle Pk, NC 27709 USA. RP Gasper-Galvin, LD (reprint author), 6 Country Club Lane, Shenandoah, IA 51601 USA. NR 44 TC 47 Z9 48 U1 1 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD OCT PY 1998 VL 37 IS 10 BP 4157 EP 4166 DI 10.1021/ie930439i PG 10 WC Engineering, Chemical SC Engineering GA 127UX UT WOS:000076369900043 ER PT J AU Joslyn, C Rocha, L AF Joslyn, C Rocha, L TI Towards a formal taxonomy of hybrid uncertainty representations SO INFORMATION SCIENCES LA English DT Article DE general information theory; fuzziness; hybrid uncertainty; nonspecificity Dempster-Shafer theory of evidence; random sets; possibility theory; evidence sets; probability theory ID SETS; INFORMATION; INTERVAL AB In this paper we present some ideas about how to formally relate various uncertainty representations together in a taxonomic structure, capturing both syntactic and semantic generalization. Fuzziness and nonspecificity are presumed as primitive concepts of uncertainty, and transitive and intransitive methods operating with nonspecificity and fuzziness are introduced to generate a base class of hybrid uncertainty representational forms. Additive, maximal, and interval constraints then complete the characterization of the most important hybrid forms. (C) 1998 Elsevier Science Inc. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Comp Res & Applicat Grp, Los Alamos, NM 87545 USA. RP Joslyn, C (reprint author), Univ Calif Los Alamos Natl Lab, Comp Res & Applicat Grp, Mail Stop B265, Los Alamos, NM 87545 USA. OI Rocha, Luis/0000-0001-9402-887X NR 27 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0020-0255 J9 INFORM SCIENCES JI Inf. Sci. PD OCT PY 1998 VL 110 IS 3-4 BP 255 EP 277 DI 10.1016/S0020-0255(98)00011-5 PG 23 WC Computer Science, Information Systems SC Computer Science GA 119EG UT WOS:000075882500009 ER PT J AU Ensz, MT Storti, DW Ganter, MA AF Ensz, MT Storti, DW Ganter, MA TI Implicit methods for geometry creation SO INTERNATIONAL JOURNAL OF COMPUTATIONAL GEOMETRY & APPLICATIONS LA English DT Article DE solid modelling; swept solids; morphing; reconstruction ID SOLID MODELS; OBJECTS AB In this paper, we briefly review the existing direct implicit geometry generation methods, which include creation of blending surfaces, a limited family of sweeps, and reconstruction of solid geometry from a sample set of surface data points. A broader approach is presented, utilizing the properties of the graph of the implicit defining function, to systematically construct swept solids and perform morphing between sections by implicit methods. C1 Univ Washington, Seattle, WA 98195 USA. RP Ensz, MT (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM sl1xp@u.washington.edu; storti@u.washington.edu; ganter@u.washington.edu NR 37 TC 6 Z9 6 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0218-1959 J9 INT J COMPUT GEOM AP JI Int. J. Comput. Geom. Appl. PD OCT-DEC PY 1998 VL 8 IS 5-6 BP 509 EP 536 DI 10.1142/S0218195998000266 PG 28 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA 125KC UT WOS:000076235900002 ER PT J AU Manrubia, SC Paczuski, M AF Manrubia, SC Paczuski, M TI A simple model of large scale organization in evolution SO INTERNATIONAL JOURNAL OF MODERN PHYSICS C LA English DT Article DE evolution; connection model; age and area; one-dimensional model ID PUNCTUATED EQUILIBRIUM; CRITICALITY AB A mathematical model of interacting species filling ecological niches left by the extinction of others is introduced. Species organize themselves into genera of all sizes. The size of a genus on average grows Linearly with its age, confirming a general relation between Age and Area proposed by Willis. The ecology exhibits punctuated equilibrium. Analytic and numerical results show that the probability distribution of genera sizes, genera lifetimes, and extinction event sizes are the same power law P(x) similar to 1/x(2) consistent with paleontological data. C1 UPC, Dept Fis & Engn Nucl, CSRG, Barcelona 08034, Spain. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Houston, Dept Phys, Houston, TX 77204 USA. RP Manrubia, SC (reprint author), UPC, Dept Fis & Engn Nucl, CSRG, C Sor Eulalia Anzizu S-N Campus Nord,B4-B5, Barcelona 08034, Spain. RI Manrubia, Susanna/K-4501-2014; OI Manrubia, Susanna/0000-0003-0134-2785 NR 17 TC 5 Z9 5 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0129-1831 J9 INT J MOD PHYS C JI Int. J. Mod. Phys. C PD OCT PY 1998 VL 9 IS 7 BP 1025 EP 1032 DI 10.1142/S0129183198000960 PG 8 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 147LG UT WOS:000077569000011 ER PT J AU Blair, SC Cook, NGW AF Blair, SC Cook, NGW TI Analysis of compressive fracture in rock using statistical techniques: Part I. A non-linear rule-based model SO INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES LA English DT Article ID CRACK GROWTH; GRANITE; SPECIMENS AB A new non-linear rule-based model for the fracture in compression of heterogeneous brittle materials such as rock is presented and used to study crack nucleation and propagation at the grain scale, We have used the model to simulate uniaxial compression tests of rock samples and results underscore the importance of crack interaction in extensile cracking of rock in compression even at low crack densities. Moreover, the model produces non-linear stress-strain behavior similar to that observed in laboratory tests. We have analyzed the stress-strain behavior and found that in these simulations fracture occurs in the following way,. First, initial damage occurs by random cracking. When approximately 15% of the sites are broken, cracks start to interact and coalesce to form larger cracks which then may propagate a significant fraction of the array length. Crack extension may be followed by crack nn est and subsequent formation of a damage zone ahead of a clack tip. Finally, a series of cracks will link and form a fracture that eventually causes failure. The model shows decreasing compressive strength with increasing size following a power-law relationship with art exponent that is similar to that determined from the study of laboratory, and field-test results. The model can also incorporate heterogeneity in the strength and geometry of rock fabric, in part II, the model is used to investigate how microscale heterogeneity in these parameters affects extensile crack growth in compression. Published by Elsevier Science Ltd. C1 Univ Calif Lawrence Livermore Natl Lab, Expt Geophys Grp, Livermore, CA 94551 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. RP Blair, SC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Expt Geophys Grp, L-201,POB 808, Livermore, CA 94551 USA. NR 30 TC 82 Z9 115 U1 1 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0148-9062 J9 INT J ROCK MECH MIN JI Int. J. Rock Mech. Min. Sci. PD OCT PY 1998 VL 35 IS 7 BP 837 EP 848 DI 10.1016/S0148-9062(98)00008-4 PG 12 WC Engineering, Geological; Mining & Mineral Processing SC Engineering; Mining & Mineral Processing GA 118MU UT WOS:000075842900001 ER PT J AU Blair, SC Cook, NGW AF Blair, SC Cook, NGW TI Analysis of compressive fracture in rock using statistical techniques: Part II. Effect of microscale heterogeneity on macroscopic deformation SO INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES LA English DT Article ID WESTERLY GRANITE; MICROMECHANICS; GROWTH AB We have performed a parameter-sensitivity analysis to evaluate the relative in importance of different types of grain-scale heterogeneity on fracture processes and compressive strength in simulated compression tests of brittle, heterogeneous materials such as rock. This was done using a non-linear, rule-based model described in a companion paper. Results presented hele indicate that heterogeneity in local stress field (due to grain shape and loading) has a fir st-ol del effect on macroscopic properties and is much more important than heterogeneity in site strength or location. In particular, increasing local stress heterogeneity lowers the mean ultimate strength following an inverse power law. Increasing heterogeneity in the lattice-site locations (i.e. irregular lattice spacing) decreases crack localization and decreases normalized crack strain energy. This result is consistent with the postulate that systems with increasing disorder I require more energy to break. Heterogeneity in site-strength distribution had a relatively minor effect on macroscopic behavior., Peak strength is dependent on the mean site strength, not on the width of the site-strength distributions. This study also revealed that percolation thresholds are much lower than those predicted from stochastic fracture models. Consequently, statistical models for rock fracture must consider, alternative percolation algorithms such as directed-bond percolation, because the standard percolation models may not be appropriate for analyzing systems where a crack interaction dominates behavior at a low fraction of sires broken. Published by Elsevier Science Ltd. C1 Univ Calif Lawrence Livermore Natl Lab, Expt Geophys Grp, Livermore, CA 94551 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. RP Blair, SC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Expt Geophys Grp, L-201,POB 808, Livermore, CA 94551 USA. NR 23 TC 26 Z9 34 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0148-9062 J9 INT J ROCK MECH MIN JI Int. J. Rock Mech. Min. Sci. PD OCT PY 1998 VL 35 IS 7 BP 849 EP 861 DI 10.1016/S0148-9062(98)00009-6 PG 13 WC Engineering, Geological; Mining & Mineral Processing SC Engineering; Mining & Mineral Processing GA 118MU UT WOS:000075842900002 ER PT J AU Warren, TL Forrestal, MJ AF Warren, TL Forrestal, MJ TI Effects of strain hardening and strain-rate sensitivity on the penetration of aluminum targets with spherical-nosed rods SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article AB We present penetration equations for rigid, spherical-nosed rods that penetrate 6061-T651 aluminum targets. The penetration models use the spherical cavity-expansion approximation and constitutive equations for the target that include strain hardening and strain-rate sensitivity. We obtained closed-form penetration equations for an incompressible target material; however, predictions for a compressible target require the numerical solution of a coupled set of nonlinear ordinary differential equations. Numerical results show the effects of compressibility, strain hardening, and strain-rate sensitivity; We also show that our penetration model requires compressibility, strain hardening, and strain-rate sensitivity to obtain good agreement with previously published depth of penetration data for striking velocities between 300 and 1200 m/s. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Warren, TL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 20 TC 55 Z9 69 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 OCT PY 1998 VL 35 IS 28-29 BP 3737 EP 3753 DI 10.1016/S0020-7683(97)00211-4 PG 17 WC Mechanics SC Mechanics GA 100PB UT WOS:000074823600007 ER PT J AU Sarrazin, P Blake, D Bish, D Vaniman, D Collins, S AF Sarrazin, P Blake, D Bish, D Vaniman, D Collins, S TI A miniature XRD/XRF instrument for in-situ characterization of Martian soils and rocks SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT Conference on X-Rays and Matter (RX 97) CY OCT 14-16, 1997 CL STRASBOURG, FRANCE SP Ecole Nationale Superieure Arts & Industries AB In the context of the exploration of Mars, the availability of an instrument for in-situ mineralogical characterization of the surface of the planet is of the highest importance. We are developing a miniature X-ray diffraction / fluorescence instrument for this specific purpose. The concept of the instrument is based on the use of a single CCD detector exposed directly to the X-rays diffracted and fluoresced by a sample. A first prototype has been realized to test the concept of simultaneous XRD and XRF measurement with a single CCD detector. This paper presents the result obtained after refinement of this instrument. The capability of the technique has been proven. Further developments are planned to propose a miniature XRD/XRF instrument for planetary exploration. The concept utilized in this project could find a range cg applications as laboratory instruments or portable instruments. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. ENESAD, LGAP, F-21036 Dijon, France. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Sarrazin, P (reprint author), NASA, Ames Res Ctr, MS 239-4, Moffett Field, CA 94035 USA. NR 10 TC 6 Z9 6 U1 4 U2 8 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD OCT PY 1998 VL 8 IS P5 BP 465 EP 470 DI 10.1051/jp4:1998559 PG 6 WC Physics, Multidisciplinary SC Physics GA 134WQ UT WOS:000076767100060 ER PT J AU Jackson, BP Miller, WP AF Jackson, BP Miller, WP TI Arsenic and selenium speciation in coal fly ash extracts by ion chromatography-inductively coupled plasma mass spectrometry SO JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY LA English DT Article ID LIQUID-CHROMATOGRAPHY; ECOSYSTEMS; RESIDUES; SE; SB AB Ion chromatography (IC) coupled to inductively coupled plasma mass spectrometry (ICP-MS) affords a sensitive technique to quantify inorganic As and Se species at trace levels; however, few studies have used the multi-element capabilities of ICP-MS as a detector for chromatographic applications. Here, IC coupled with ICP-MS was used to determine As(III), As(V), Se(IV), and Se(VI) in aqueous extracts of coal fly ash. All four species were resolved, with retention times of 1.1, 2.9, 4.8, and 6.3 min for As(III), Se(IV), Se(VI), and As(V), respectively. Because all species were fully resolved, the resulting chromatograms were obtained by summing signal intensities for m/z 75 + m/z 82. Absolute detection limits of 7.2, 87, 117, and 28 pg for As(III), Se(rv), Se(VI), and As(V), respectively, were obtained, corresponding to 0.072, 0.868, 1.174, and 0.284 mu g l(-1) for a 100 mu l injection volume. The technique was used to determine the speciation of As and Se in aqueous extracts of 24 coal fly ash samples including NIST SRM 1633b. The predominant species were As(V) and Se(IV), with As(III) detected in two low pH fly ashes. Extraction of fly ashes at pH 5 altered the concentrations of total soluble As and Se but did not affect the predominant As and Se speciation. C1 Univ Georgia, Dept Crop & Soil Sci, Athens, GA 30602 USA. RP Jackson, BP (reprint author), Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Drawer E, Aiken, SC 29802 USA. NR 20 TC 46 Z9 50 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0267-9477 J9 J ANAL ATOM SPECTROM JI J. Anal. At. Spectrom. PD OCT PY 1998 VL 13 IS 10 BP 1107 EP 1112 DI 10.1039/a806159i PG 6 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 131KT UT WOS:000076575800006 ER PT J AU Tsuruta, H Brennan, S Rek, ZU Irving, TC Tompkins, WH Hodgson, KO AF Tsuruta, H Brennan, S Rek, ZU Irving, TC Tompkins, WH Hodgson, KO TI A wide-bandpass multilayer monochromator for biological small-angle scattering and fiber diffraction studies SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article ID X-RAY-SCATTERING; TIME-RESOLVED CRYSTALLOGRAPHY; SYNCHROTRON-RADIATION; REFLECTION; INTERMEDIATE AB Many biological applications of small-angle X-ray scattering, in particular time-resolved studies, are often limited by the flux incident on the sample due to the smaller scattering cross section of biological specimens. The wider-energy bandpass of a monochromator that consists of a pair of synthetic multilayer microstructures can, in principle, provide a flux two orders of magnitude higher than that of an Si(lll) double-crystal monochromator. Two types of multilayers have been installed in the standard monochromator tank of beamline 4-2 at the Stanford Synchrotron Radiation Laboratory; the multilayer beam has been characterized for studies of small-angle X-ray scattering/diffraction from biological materials. Reflectivity and topography measurements indicate that the multilayers are quite adequate for these applications and a pair of Mo/B4C multilayers provided a 10-30 times increase in flux, compared with the flux level obtained with an Si(111) double-crystal monochromator. The increased flux level is very useful in time-resolved scattering studies as well as for recording weak scattering at higher angles. Having carried out many solution scattering and fiber diffraction experiments, we conclude that the use of multilayer does not result in significant broadening of diffraction peaks nor does it have appreciable effects on small-angle resolution. No significant increase in background is observed. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Stanford Univ, Dept Chem, Stanford, CA 94025 USA. IIT, Dept Biol Chem & Phys Sci, Chicago, IL 60616 USA. RP Tsuruta, H (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, POB 4349,MS 69, Stanford, CA 94309 USA. EM tsuruta@ssrl.slac.stanford.edu NR 36 TC 52 Z9 53 U1 1 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0021-8898 J9 J APPL CRYSTALLOGR JI J. Appl. Crystallogr. PD OCT 1 PY 1998 VL 31 BP 672 EP 682 DI 10.1107/S0021889898002702 PN 5 PG 11 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 142CV UT WOS:000077183100004 ER PT J AU Burger, K Cox, D Papoular, R Prandl, W AF Burger, K Cox, D Papoular, R Prandl, W TI The application of resonant scattering techniques to ab initio structure solution from powder data using SrSO4 as a test case SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article ID MAXIMUM-ENTROPY METHOD; ANOMALOUS SCATTERING; STRUCTURE REFINEMENT; DIFFRACTION DATA; SYNCHROTRON; DENSITIES; NEUTRON AB The application of resonant (anomalous) scattering techniques to ab initio structure solution from powder data is demonstrated for the compound SrSO4. This material is orthorhombic, in space group Pnma (a = 8.359, b = 5.351, c = 6.869 Angstrom, Z = 4), with 11 variable atomic positional parameters, and gives a fairly complex powder pattern with many overlapping peaks. Accurate high-resolution synchrotron X-ray powder diffraction data were obtained at three energies: 14, 225 and 5133 eV below the Sr K edge. From combinations of two of the three data-sets, partial Patterson densities were derived and used to phase the 71 uniquely resolved reflections, allowing a complete solution of the rest of the structure. Maximum entropy methods were found to be far superior to standard Fourier methods in the reconstruction of the electron-density distribution. The techniques of data collection, analysis and phase determination required for resonant scattering experiments of this type are described in detail. C1 Univ Tubingen, Inst Kristallog, D-72070 Tubingen, Germany. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. Ctr Etud Saclay, Leon Brillouin Lab, F-91191 Gif Sur Yvette, France. RP Burger, K (reprint author), Univ Tubingen, Inst Kristallog, Charlottenstr 33, D-72070 Tubingen, Germany. NR 23 TC 12 Z9 12 U1 0 U2 4 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0021-8898 J9 J APPL CRYSTALLOGR JI J. Appl. Crystallogr. PD OCT 1 PY 1998 VL 31 BP 789 EP 797 DI 10.1107/S0021889898006293 PN 5 PG 9 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 142CV UT WOS:000077183100018 ER PT J AU Xu, YW Carmichael, GR AF Xu, YW Carmichael, GR TI Modeling the dry deposition velocity of sulfur dioxide and sulfate in Asia SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article; Proceedings Paper CT 5th International Conference on Atmospheric Science and Applications to Air Quality CY JUN 18-20, 1996 CL SEATTLE, WASHINGTON SP Amer Meteorol Soc, Air & Waste Management Assoc, US EPA, NASA, World Meteorol Org, US Weather Serv, UNESCO, Comm Sci & Technol Developing Countries, ASIA OCEANIA Network Biol Sci, Univ Iowa, Ctr Global & Reg Environm Res, Univ Washington ID LONG-RANGE TRANSPORT; LAND-USE; SO2; GASES; PARAMETERIZATION; VEGETATION; SURFACE; PINE AB The dry deposition model was created to estimate SO2 and sulfate dry deposition velocities over nine land use types in Asia. The study domain is 20 degrees S-50 degrees N, 39 degrees-154 degrees E. Monthly averaged 1 degrees x 1 degrees dry deposition velocities are estimated for four seasons. Model results show that the dry deposition velocity of SO2 demonstrates strong seasonal and diurnal variability in summer, fall, and spring. In summer, the daytime velocity (in centimeters per second) for SO2 forests is 0.4, over cultivation is 0.2, grassland is 0.5, and ocean is 0.8. Nighttime values of SO2 are two or three times less than daytime values. In winter, the deposition velocity of SO2 does not show much diurnal variability-the value is 0.1-0.2 except over ocean, when it is 0.5. Contrary to SO2, the dry deposition velocity of sulfate only slightly varies with seasons and time of the day. Generally, its value is less than 0.1. C1 Univ Iowa, Dept Chem & Biochem Engn, Ctr Global & Reg Environm Res, Iowa City, IA 52242 USA. RP Xu, YW (reprint author), Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NR 30 TC 21 Z9 21 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD OCT PY 1998 VL 37 IS 10 BP 1084 EP 1099 DI 10.1175/1520-0450(1998)037<1084:MTDDVO>2.0.CO;2 PN 1 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 128CK UT WOS:000076387500009 ER PT J AU Pinnaduwage, LA Datskos, PG Tav, C AF Pinnaduwage, LA Datskos, PG Tav, C TI Electron attachment to photofragments and Rydberg states in laser-irradiated CCl2F2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID RADIO-FREQUENCY DISCHARGE; CF2CL2; CCL3F; PHOTOCHEMISTRY; SPECTROSCOPY; COEFFICIENTS; SILANE; CFCL3 AB We report electron attachment measurements on ArF-excimer-laser irradiated CCl2F2, obtained using an improved experimental technique that allows simultaneous measurements on multiple electron attaching species. Compared to a maximum electron attachment rate constant of similar to 2 x 10(-9) cm(3) s(-1) for the ground electronic state of CCl2F2, we measure an order of magnitude larger rate constant for the CClF2 radical produced via laser photodissociation. However, the highly excited electronic states of CCl2F2 produced by the laser irradiation have an associated electron attachment rate constant that is at least four orders of magnitude larger compared to the ground electronic state value. Implications of these findings for plasma processing discharges using CCl2F2 are discussed. (C) 1998 American Institute of Physics. [S0021-8979(98)08519-3]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Pinnaduwage, LA (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 41 TC 3 Z9 3 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD OCT 1 PY 1998 VL 84 IS 7 BP 3442 EP 3450 DI 10.1063/1.368518 PG 9 WC Physics, Applied SC Physics GA 124LX UT WOS:000076184800002 ER PT J AU Huang, HC Gilmer, GH de la Rubia, TD AF Huang, HC Gilmer, GH de la Rubia, TD TI An atomistic simulator for thin film deposition in three dimensions SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID VAPOR-DEPOSITION; CRYSTAL-GROWTH; BOUNDARIES; DIFFUSION; ENERGIES; NICKEL; MODEL AB We describe an atomistic simulator for thin film deposition in three dimensions (ADEPT). The simulator is designed to bridge the atomic and mesoscopic length scales by using efficient algorithms, including an option to speed up surface diffusion using events with multiple diffusion hops. Sputtered particles are inserted and assigned ballistic trajectories with angular distributions appropriate for magnetron sputtering. Atoms on the surface of the film execute surface diffusion hops with rates that depend on the local configuration, and are consistent with microscopic reversibility. The potential energies are chosen to match information obtained from a database of first principles and molecular dynamics (MD) calculations. Efficient computation is accomplished by selecting atoms with probabilities that are proportional to their hop rates. A first implementation of grain boundary effects is accomplished by including an orientation variable with each occupied site. Energies and mobilities are assigned to atoms in grain boundaries using values obtained from MD. In this article we describe simulations of the deposition of aluminum. The film atoms occupy face centered cubic lattice sites of a single crystal. Three-dimensional films deposited on vias and trenches up to 0.05 mm in size have been simulated. We discuss these films in the context of step coverage issues, and scaling to macroscopic sizes. Texture development is discussed in the light of simulations showing anisotropic crystal growth. Future versions of ADEPT will include a more complete model of grain development in thin films. [S0021-8979(98)04118- 8]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. RP Huang, HC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM mmhanchen@polyu.edu.hk RI Huang, Hanchen/A-9323-2008 NR 22 TC 179 Z9 196 U1 4 U2 51 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD OCT 1 PY 1998 VL 84 IS 7 BP 3636 EP 3649 DI 10.1063/1.368539 PG 14 WC Physics, Applied SC Physics GA 124LX UT WOS:000076184800026 ER PT J AU Zhang, Y Mascarenhas, A Deb, S AF Zhang, Y Mascarenhas, A Deb, S TI Effects of excitons on solar cells SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SILICON AB We have studied the effects of excitons on the two key parameters of a Si solar cell: the dark-saturation current and short-circuit current. We have found that the effect of excitons on the dark-saturation current is very sensitive to the boundary condition for excess excitons at the edge of the depletion region. With the assumption of near equilibrium between the electrons and excitons, we find that the exciton effect is rather small, which is contrary to the conclusion of significant reduction in the dark-saturation current made in previous work with the assumption of no excess excitons at the edge [J. Appl. Phys. 79, 195 (1996)]. The results for the short-circuit current are very similar to the previous work. However, the analytical results for the carrier concentrations and the corresponding currents are now presented in a simple way in which the physical meaning of each individual term is elucidated or revealed. Furthermore, we have found, for practical purposes, very accurate approximate solutions for the carrier concentrations and corresponding currents. Our conclusion is that the major effect of excitons on the Si solar cell performance relies on whether the effective diffusion length (L-1) of the coupled electron-exciton system is significantly greater than that of the electron itself (L-e). (C) 1998 American Institute of Physics. [S0021-8979(98)05519-4]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Zhang, Y (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 5 TC 9 Z9 9 U1 2 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD OCT 1 PY 1998 VL 84 IS 7 BP 3966 EP 3971 DI 10.1063/1.368575 PG 6 WC Physics, Applied SC Physics GA 124LX UT WOS:000076184800070 ER PT J AU Luine, JA Kresin, VZ AF Luine, JA Kresin, VZ TI Critical current in high T-c grain boundary junctions SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID YBA2CU3O7-DELTA THIN-FILMS; JOSEPHSON-JUNCTIONS; MICROSTRUCTURE; SQUIDS AB The temperature dependence of YBa2Cu3O7-delta (YBCO) grain boundary junction (GBJ) maximum critical current I-M is measured and successfully described by a theoretical model that incorporates both the proximity effect and tunneling within a superconductor-normal-insulator-normal-superconductor (SNINS) structure. The correspondence between experiment and theory shows that that GBJs can be described by an S-alpha -N-beta-I-N-beta-S-alpha structure where S-alpha,N-beta, and I are superconducting, normal conducting, and insulating states of YBCO. The different YBCO electrical properties within a GBJ are the result of oxygen loss at the grain boundary. Correspondence between experimental data and theoretical predictions is obtained in most cases with the adjustment of just one parameter: alpha = sigma(-1) L-beta/xi, where sigma the tunneling probability through the S-N interface, L-beta is the width of the normal barrier, and xi is the coherence length in the superconductor S-alpha. The theory also predicts that a grain boundary junction critical current density J(c) is related to reduced normal resistance rho(n) by J(c)similar to rho(n)(gamma) with -2 less than or equal to gamma less than or equal to-1 as widely observed. Thus, we postulate that many natural and artificial c grain boundaries have an S-alpha-N-beta-I-N-beta-S-alpha structure and, therefore, the previously developed theory of S-alpha-N-beta-I-N-beta-S-alpha structures applied here has wide applicability to the study and analysis of YBCO grain boundary physics. (C) 1998 American Institute of Physics. [S0021-8979(98)00519-2]. C1 TRW Co Inc, Space & Elect Grp, Redondo Beach, CA 90278 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP TRW Co Inc, Space & Elect Grp, Redondo Beach, CA 90278 USA. EM vzkresin@lbl.gov NR 32 TC 5 Z9 5 U1 1 U2 4 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 OCT 1 PY 1998 VL 84 IS 7 BP 3972 EP 3979 DI 10.1063/1.368576 PG 8 WC Physics, Applied SC Physics GA 124LX UT WOS:000076184800071 ER PT J AU Maree, CHM Weller, RA Feldman, LC Pakbaz, K Lee, HWH AF Maree, CHM Weller, RA Feldman, LC Pakbaz, K Lee, HWH TI Accurate thickness/density measurements of organic light-emitting diodes SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CURRENT TRANSPORT; DEVICES; ELECTROLUMINESCENCE; FILMS; DEGRADATION; POLYMERS; LAYERS; MODEL; IONS AB We report on the use of Rutherford backscattering spectroscopy for thickness analysis of organic light-emitting diode structures (OLEDs) with subnanometer resolution and a spatial resolution <1 mm. A careful study of ion beam induced effects revealed some organic film degradation, but not so severe as to inhibit meaningful measurements. The method is independent of the substrate and is still applicable if the organic film is capped with a metal cathode. Common OLED materials have been the subject of this study: poly(2-methoxy,5-(2'-ethylhexoxy)-1,4-phenylene-vinylene (MEH-PPV), N',N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1' biphenyl-4,4'-diamine (TPD), and tris-(8-hydroxyquinoline) aluminum (Alq(3)). The densities of thin films of evaporated TPD (rho = 1.22 +/- 0.05 g/cm(3)) and Alq(3) (rho = 1.51 +/- 0.03 g/cm(3)) have been established. (C) 1998 American Institute of Physics. [S0021-8979(98)06919-9]. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Lawrence Livermore Natl Lab, Photon Grp, Livermore, CA 94551 USA. Vanderbilt Univ, Dept Elect & Comp Engn, Nashville, TN 37235 USA. RP Vanderbilt Univ, Dept Phys & Astron, 221 Kirkland Hall, Nashville, TN 37235 USA. EM Robert.A.Weller@Vanderbilt.Edu; feldman@ctrvax.vandeerbilt.edu NR 32 TC 21 Z9 21 U1 0 U2 7 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 OCT 1 PY 1998 VL 84 IS 7 BP 4013 EP 4016 PG 4 WC Physics, Applied SC Physics GA 124LX UT WOS:000076184800077 ER PT J AU Wos, L AF Wos, L TI Automating the search for elegant proofs SO JOURNAL OF AUTOMATED REASONING LA English DT Article DE automated reasoning; elegant proofs; Otter; Boolean algebra ID RESONANCE AB The research reported in this article was spawned by a colleague's request to find an elegant proof (of a theorem from Boolean algebra) to replace his proof consisting of 816 deduced steps. The request was met by finding a proof consisting of 100 deduced seeps. The methodology used to obtain the far shorter proof is presented in detail through a sequence of experiments. Although clearly not an algorithm, the methodology is sufficiently general to enable its use for seeking elegant proofs regardless of the domain of study. In addition to (usually) being more elegant, shorter proofs often provide the needed path to constructing a more efficient circuit, a more effective algorithm, and the like. The methodology relies heavily on the assistance of McCune's automated reasoning program OTTER. Of the aspects of proof elegance, the main focus here is on proof length, with brief attention paid to the type of term present, the number of variables required, and the complexity of deduced steps. The methodology is iterative, relying heavily on the use of three strategies: the resonance strategy, the hot list strategy, and McCune's ratio strategy. These strategies, as well as other features on which the methodology relies, do exhibit tendencies that can be exploited in the search for shorter proofs and for other objectives. To provide some insight regarding the value of the methodology, I discuss its successful application to other problems from Boolean algebra and to problems from lattice theory. Research suggestions and challenges are also offered. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0168-7433 J9 J AUTOM REASONING JI J. Autom. Reasoning PD OCT PY 1998 VL 21 IS 2 BP 135 EP 175 DI 10.1023/A:1005847113370 PG 41 WC Computer Science, Artificial Intelligence SC Computer Science GA 126CC UT WOS:000076274400001 ER PT J AU Hu, P Elliott, J McCready, P Skowronski, E Garnes, J Kobayashi, A Brubaker, RR Garcia, E AF Hu, P Elliott, J McCready, P Skowronski, E Garnes, J Kobayashi, A Brubaker, RR Garcia, E TI Structural organization of virulence-associated plasmids of Yersinia pestis SO JOURNAL OF BACTERIOLOGY LA English DT Article ID BORDETELLA-PERTUSSIS; NUCLEOTIDE-SEQUENCE; INSERTION-SEQUENCE; DNA FRAGMENT; Y-PESTIS; PROTEIN; GENES; PSEUDOTUBERCULOSIS; ANTIGEN; CELL AB The complete nucleotide sequence and gene organization of the three virulence plasmids from Yersinia pestis KIM5 were determined. Plasmid pPCP1 (9,610 bp) has a GC content of 45.3% and encodes two previously known virulence factors, an associated protein, and a single copy of IS100. Plasmid pCD1 (70,504 bp) has a GC content of 44.8%. It is known to encode a number of essential virulence determinants, regulatory functions, and a multiprotein secretory system comprising the low-calcium response stimulation that is shared with the other two Yersinia species pathogenic for humans (Y. pseudotuberculosis and Y. enterocolitica). A new pseudogene, which occurs as an intact gene in the Y. enferocolitica and Y. pseudotuberculosis-derived analogues, was found in pCD1. It corresponds to that encoding the lipoprotein YlpA. Several intact and partial insertion sequences and/or transposons were also found in pCD1, as well as six putative structural genes with high homology to proteins of unknown function in other yersiniae. The sequences of the genes involved in the replication of pCD1 are highly homologous to those of the cognate plasmids in Y. pseudotuberculosis and Y. enterocolitica, but their localization within the plasmid differs markedly from those of the latter. Plasmid pMT1 (100,984 bp) has a GC content of 50.2%. It possesses two copies of IS100, which are located 25 kb apart and in opposite orientations. Adjacent to one of these IS100 inserts is a partial copy of IS285. A single copy of an IS200-like element (recently named IS154I) was also located in pMT1. In addition to 5 previously described genes, such as murine toxin, capsule antigen, capsule anchoring protein, etc., 30 homologues to genes of several bacterial species were found in this plasmid, and another 44 open reading frames without homology to any known or hypothetical protein in the databases were predicted. C1 Lawrence Livermore Natl Lab, Ctr Human Genome, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Michigan State Univ, Dept Microbiol, E Lansing, MI 48824 USA. RP Garcia, E (reprint author), Lawrence Livermore Natl Lab, Ctr Human Genome, Biol & Biotechnol Res Program, L-452,7000 East Ave, Livermore, CA 94550 USA. EM garcial2@llnl.gov NR 61 TC 123 Z9 168 U1 0 U2 5 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD OCT PY 1998 VL 180 IS 19 BP 5192 EP 5202 PG 11 WC Microbiology SC Microbiology GA 122YX UT WOS:000076100000026 PM 9748454 ER PT J AU Ladd, AJC Kinney, JH AF Ladd, AJC Kinney, JH TI Numerical errors and uncertainties in finite-element modeling of trabecular bone SO JOURNAL OF BIOMECHANICS LA English DT Article DE finite-element modeling; trabecular bone AB Although micromechanical finite-element models are being increasingly used to help interpret the results of bio-mechanical tests, there has not yet been a systematic study of the numerical errors and uncertainties that occur with these methods. In this work, finite-element models of human Ll vertebra have been used to analyze the sensitivity of the calculated elastic moduli to resolution, boundary conditions, and variations in the Poisson's ratio of the tissue material. Our results indicate that discretization of the bone architecture, inherent in the tomography process, leads to an underestimate in the calculated elastic moduli of about 20% at 20 mu m resolution; these errors vary roughly linearly with the size of the image voxels. However, it turns out that there is a cancellation of errors between the softening introduced by the discretization of the bone architecture and the excess bending resistance of eight-node hexahedral finite elements. Our empirical finding is that eight-node cubic elements of the same size as the image voxels lead to the most accurate calculation for a given number of elements, with errors of less than 5% at 20 mu m resolution. Comparisons with mechanical testing are also hindered by uncertainties in the grip conditions; our results show that these uncertainties are of comparable magnitude to the systematic differences in mechanical testing methods. Both discretization errors and uncertainties in grip conditions have a smaller effect on relative moduli, used when comparing between different specimens or different load directions, than on an absolute modulus. The effects of variations in the Poisson's ratio of the bone tissue were found to be negligible. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Ladd, AJC (reprint author), Univ Florida, Dept Chem Engn, Room 227, Gainesville, FL 32611 USA. EM ladd@che.ufl.edu NR 9 TC 55 Z9 55 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0021-9290 J9 J BIOMECH JI J. Biomech. PD OCT PY 1998 VL 31 IS 10 BP 941 EP 945 DI 10.1016/S0021-9290(98)00108-0 PG 5 WC Biophysics; Engineering, Biomedical SC Biophysics; Engineering GA 139ZR UT WOS:000077061600010 PM 9840760 ER PT J AU Telenkov, SA Smithies, DJ Goodman, DM Tanenbaum, BS Nelson, JS Milner, TE AF Telenkov, Sergey A. Smithies, Derek J. Goodman, Dennis M. Tanenbaum, B. Samuel Nelson, J. Stuart Milner, Thomas E. TI INFRARED IMAGING OF IN VIVO MICROVASCULATURE FOLLOWING PULSED LASER IRRADIATION SO JOURNAL OF BIOMEDICAL OPTICS LA English DT Article DE CAM; laser; infrared imaging; FPA camera AB Infrared emission images of the chick chorioallantoic membrane (CAM) microvasculature following pulsed laser irradiation were recorded using a high speed infrared focal plane array camera. A three-dimensional tomographic reconstruction algorithm was applied to compute the initial space-dependent temperature increase in discrete CAM blood vessels caused by light absorption. The proposed method may provide consistent estimates of the physical dimensions of subsurface blood vessels and may be useful in understanding a variety of biomedical engineering problems involving laser-tissue interaction. (C) 1998 Society of Photo-Optical Instrumentation Engineers. C1 [Telenkov, Sergey A.; Milner, Thomas E.] Univ Texas Austin, Biomed Engn Program, Austin, TX 78712 USA. [Smithies, Derek J.; Nelson, J. Stuart] Univ Calif Irvine, Beckman Laser Inst & Med Clin, Irvine, CA 92715 USA. [Goodman, Dennis M.] Lawrence Livermore Natl Lab, Livermore, CA USA. [Tanenbaum, B. Samuel] Harvey Mudd Coll, Dept Engn, Claremont, CA 91711 USA. RP Telenkov, SA (reprint author), Univ Texas Austin, Biomed Engn Program, Austin, TX 78712 USA. EM sergey@mail.utexas.edu FU Biomedical Engineering Research grant from the Whitaker Foundation [WF-21025]; National Institutes of Health [RO1AR4243701A1]; Office of Naval Research [N00014-94-0874]; Department of Energy [DE-FG03-91] FX This work was supported by a Biomedical Engineering Research grant (WF-21025) from the Whitaker Foundation. Support from the National Institutes of Health (RO1AR4243701A1), the Office of Naval Research (N00014-94-0874), and the Department of Energy (DE-FG03-91) is also gratefully acknowledged. NR 18 TC 8 Z9 8 U1 0 U2 0 PU SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 1083-3668 EI 1560-2281 J9 J BIOMED OPT JI J. Biomed. Opt. PD OCT PY 1998 VL 3 IS 4 BP 391 EP 395 DI 10.1117/1.429848 PG 5 WC Biochemical Research Methods; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Biochemistry & Molecular Biology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA V32RN UT WOS:000208968400002 PM 23015137 ER PT J AU Smithpeter, C Dunn, A Drezek, R Collier, T Richards-Kortum, R AF Smithpeter, Colin Dunn, Andrew Drezek, Rebekah Collier, Tom Richards-Kortum, Rebecca TI NEAR REAL TIME CONFOCAL MICROSCOPY OF CULTURED AMELANOTIC CELLS: SOURCES OF SIGNAL, CONTRAST AGENTS AND LIMITS OF CONTRAST SO JOURNAL OF BIOMEDICAL OPTICS LA English DT Article DE confocal microscopy; neoplasia; scattering; imaging; near real time AB The use of high resolution, in vivo confocal imaging for noninvasive assessment of tissue pathology may offer a clinically important adjunct to standard histopathological techniques. To augment the present understanding of both the capabilities and limitations of in vivo confocal imaging, we investigated cellular sources of image contrast in amelanotic tissues, how contrast can be enhanced with external agents and how contrast is degraded by the scattering of overlying cells. A high-resolution reflected light confocal microscope was constructed and used to obtain images of various types of unstained amelanotic cells in suspension in real time before and after the addition of contrast agents. Reflectance images were compared to phase contrast images and electron micrographs to identify morphology visible with real time reflected light confocal microscopy. Mechanisms which decrease image contrast, including interference effects and scattering in overlying layers of cells, were considered. In amelanotic epithelial cells, fluctuations in the nuclear index of refraction provide signal which can be imaged even under several overlying cell layers. Acetic acid is an external contrast agent which can enhance this nuclear backscattering. Image contrast is degraded by the presence of multiple scattering in overlying cell layers. The degradation of image contrast by cell scattering depends on the scattering phase function; in vitro models which use polystyrene microspheres to approximate tissue underestimate the actual degradation caused by cell scattering. The loss in contrast can be explained using a finite difference time domain model of cellular scattering. We conclude that near real time reflected light confocal microscopy can be used to study cell morphology in vivo. Contrast degradation due to overlying tissue is a concern and cannot adequately be modeled using conventional tissue phantoms; however, acetic acid may be used to substantially increase intrinsic contrast, allowing imaging at significant depths despite distortion from overlying layers. (C) 1998 Society of Photo-Optical Instrumentation Engineers. C1 [Smithpeter, Colin; Dunn, Andrew; Drezek, Rebekah; Collier, Tom; Richards-Kortum, Rebecca] Univ Texas Austin, Dept Elect & Comp Engn, Austin, TX 78712 USA. RP Smithpeter, C (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Dunn, Andrew/I-9527-2014; Richards-Kortum, Rebecca/P-4074-2014 OI Richards-Kortum, Rebecca/0000-0003-2347-9467 FU National Science Foundation [BCS-9157202]; National Institutes of Health [1R55CA73920-01]; DHHS-National Institutes of Health [CA59739] FX The authors gratefully acknowledge the contributions of Rohit Prasakumar and Sumanth Gopinath. Grants from the National Science Foundation (BCS-9157202) and the National Institutes of Health (1R55CA73920-01) are acknowledged. The authors express their appreciation to Kimberly Kline (Professor, Division of Nutrition, University of Texas at Austin) and the resources of DHHS-National Institutes of Health grant CA59739 for supplying the human breast cancer cells. NR 22 TC 51 Z9 51 U1 0 U2 1 PU SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 1083-3668 EI 1560-2281 J9 J BIOMED OPT JI J. Biomed. Opt. PD OCT PY 1998 VL 3 IS 4 BP 429 EP 436 DI 10.1117/1.429853 PG 8 WC Biochemical Research Methods; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Biochemistry & Molecular Biology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA V32RN UT WOS:000208968400008 PM 23015143 ER PT J AU Falconer, JL Magrini-Bair, KA AF Falconer, JL Magrini-Bair, KA TI Photocatalytic and thermal catalytic oxidation of acetaldehyde on Pt/TiO(2) SO JOURNAL OF CATALYSIS LA English DT Article ID PHOTOOXIDATION; TEMPERATURE; SELECTIVITY; ETHYLENE; PLATINUM; TITANIA; ETHANOL; AIR AB Low concentrations of acetaldehyde in air (60 ppm) were oxidized over TiO(2) (Degussa P25) and 0.5% Pt/TiO(2) catalysts from 24 to 200 degrees C by photocatalytic and thermal catalytic reactions. On Pt/TiO(2), the contribution by photocatalytic oxidation (PCO) is a maximum at 140 degrees C, where conversion is 2.8 times that at 24 degrees C. Titania without Pt deactivates rapidly during PCO at elevated temperature due to a thermal catalytic reaction that takes place in parallel with PCO, but the addition of Pt dramatically slows deactivation. Apparently, Pt supplies spillover oxygen onto the TiO(2), and the oxygen oxidizes the acetaldehyde decomposition products in a dark reaction. Deactivated TiO(2) without Pt was regenerated by PCO at room temperature. Seven distinct reactions (photocatalytic and thermal catalytic) are identified on Pt/TiO(2). (C) 1998 Academic Press C1 Univ Colorado, Dept Chem Engn, Boulder, CO 80309 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Falconer, JL (reprint author), Univ Colorado, Dept Chem Engn, Boulder, CO 80309 USA. EM john.falconer@colorado.edu NR 22 TC 141 Z9 151 U1 0 U2 18 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9517 J9 J CATAL JI J. Catal. PD OCT 1 PY 1998 VL 179 IS 1 BP 171 EP 178 DI 10.1006/jcat.1998.2215 PG 8 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 127QX UT WOS:000076363000016 ER PT J AU Hershlag, N Hurley, I Woodward, J AF Hershlag, N Hurley, I Woodward, J TI A simple method to demonstrate the enzymatic production of hydrogen from sugar SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article ID PYROCOCCUS-FURIOSUS; ARCHAEBACTERIUM; GLUCOSE C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Syosset High Sch, Syosset, NY 11791 USA. N Shore Univ Hosp, Dept Obstet & Gynecol, Manhasset, NY 11030 USA. RP Woodward, J (reprint author), Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. NR 12 TC 3 Z9 3 U1 1 U2 40 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD OCT PY 1998 VL 75 IS 10 BP 1270 EP 1274 PG 5 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA 120NR UT WOS:000075962900013 ER PT J AU Yourshaw, I Lenzer, T Reiser, G Neumark, DM AF Yourshaw, I Lenzer, T Reiser, G Neumark, DM TI Zero electron kinetic energy spectroscopy of the KrBr-, XeBr-, and KrCl- anions SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID THRESHOLD PHOTODETACHMENT SPECTROSCOPY; CLOSED-SHELL ATOMS; GAS-HALIDE-SYSTEMS; INTERACTION POTENTIALS; RARE-GAS; RESOLUTION; FORCES; IONS; STATES; APPROXIMATION AB Three rare-gas halide (RgX(-)) anions, KrBr-, XeBr-, and KrCl-, and the corresponding neutral, open-shell van der Waals complexes are studied with anion zero electron kinetic energy spectroscopy. The spectra for each system reveal well-resolved progressions in the low frequency vibrations of the anion and one or more of the three neutral electronic states accessed by photodetachment, providing a detailed spectroscopic probe of the Rg-X- and Rg-X interaction potentials. In the case of KrBr-, transitions to all three of the "covalent" neutral electronic states (the X1/2, I3/2, and II1/2 states) were observed. For XeBr-, transitions to the X1/2 and II1/2 neutral states were observed. For KrCl-, only the X1/2 state could be studied. From our data, we construct model potentials for the anion and each observed neutral state, and these are compared with other experimental and theoretical potentials. (C) 1998 American Institute of Physics. [S0021-9606(98)01037-X]. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Yourshaw, I (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Neumark, Daniel/B-9551-2009 OI Neumark, Daniel/0000-0002-3762-9473 NR 43 TC 47 Z9 49 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 1 PY 1998 VL 109 IS 13 BP 5247 EP 5256 DI 10.1063/1.477141 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 123YF UT WOS:000076152700010 ER PT J AU Li, X Wang, LS AF Li, X Wang, LS TI The chemical bonding and electronic structure of RhC, RhN, and RhO by anion photoelectron spectroscopy SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ALL-ELECTRON; MOLECULE; CLUSTERS; OXIDES AB The electronic structure and chemical bonding of RhC, RhN, and RhO were experimentally investigated using anion photoelectron spectroscopy. Vibrationally resolved photoelectron spectra of RhC-, RhN-, and RhO- were obtained at two detachment photon energies, 532 (2.33 eV) and 355 nm (3.49 eV). Electron affinities, low-lying electronic states, and vibrational frequencies are reported for the neutral diatomic molecules. The adiabatic electron affinities are similar for the three molecules and increase slightly from RhC to RhO (RhC: 1.46; RhN: 1.51; RhO: 1.58 eV). The low-lying electronic states are rather simple for RhC, with its first electronic excited state occurring at 9400 cm(-1) above the ground state, whereas those of RhN and RhO are more complicated, with numerous closely spaced low-lying electronic states. Excited states of the anions were also observed for RhC- and RhN-. The trend of the chemical bonding from RhC to RhO is discussed based on the experimental results. (C) 1998 American Institute of Physics. [S0021-9606(98)00337-7]. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Wang, LS (reprint author), Washington State Univ, Dept Phys, 2710 Univ Dr, Richland, WA 99352 USA. NR 15 TC 31 Z9 31 U1 1 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 1 PY 1998 VL 109 IS 13 BP 5264 EP 5268 DI 10.1063/1.477143 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 123YF UT WOS:000076152700012 ER PT J AU Hemmi, N Suits, AG AF Hemmi, N Suits, AG TI The dynamics of hydrogen abstraction reactions: Crossed-beam reaction Cl+n-C5H12 -> C5H11+HCl SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CHEMICAL-DYNAMICS; AB-INITIO; PRODUCT; CHLORINE; SECTIONS; DISTRIBUTIONS; HYDROCARBONS; ATOMS AB We present a crossed molecular beam study of the dynamics of the metathesis reaction Cl + n-C5H12-->HCl+C5H11 at a collision energy of 16.8 kcal/mol. The experiments were conducted on the Chemical Dynamics Beamline at the Advanced Light Source, using tunable undulator radiation to effect soft ionization of the pentyl radical product. Laboratory angular distributions and time-of-flight spectra at many laboratory angles were used to obtain the center-of-mass translational energy and angular distributions. These distributions were found to be strongly coupled, with the forward scattered pentyl radical formed extremely cold, while the backscattered radicals were formed leaving nearly 15 kcal/mol in internal energy in the products. These results are contrasted with recent studies on the analogous reaction with propane, suggesting in this case direct involvement of the carbon skeleton in the collision process. [S0021-9606(98)02437-4]. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Hemmi, N (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. NR 22 TC 35 Z9 35 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 1 PY 1998 VL 109 IS 13 BP 5338 EP 5343 DI 10.1063/1.476523 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 123YF UT WOS:000076152700021 ER PT J AU Stranges, D Stemmler, M Yang, XM Chesko, JD Suits, AG Lee, YT AF Stranges, D Stemmler, M Yang, XM Chesko, JD Suits, AG Lee, YT TI UV photodissociation dynamics of allyl radical by photofragment translational spectroscopy SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RESONANT MULTIPHOTON IONIZATION; PHOTOELECTRON-SPECTROSCOPY; VIBRATIONAL FREQUENCIES; 193.3 NM; SPECTRUM; STATE; ETHYLENE; ABINITIO; C3H5; TRANSITION AB Photodissociation of the allyl radical, CH2CHCH2, has been studied using the method of molecular beam photofragment translational spectroscopy following excitation to the (C) over tilde(2 B-2(1)) and (A) over tilde(1 B-2(1)) states by 248 and 351 nm photons. Two different primary channels have been detected following 248 nm excitation: H-atom loss (84%) and CH3 elimination (16%). From the product translational energy distribution and polarization dependence studies, dissociation processes from the ground-state C3H5 potential energy surface are inferred for both wavelengths. At 248 nm there may also be a contribution to the H-atom loss channel from predissociation by a higher electronically excited state. Rice-Ramsperger-Kassel-Marcus (RRKM) calculations show that the formation of cyclopropene is not important, while formation of allene and methylacetylene from dissociation of 1- and 2-propenyl radicals are important reaction pathways at both wavelengths. Translational energy distributions peaking well away from zero provide evidence for CH3 elimination directly from an allylic structure through a four-member cyclic transition state. (C) 1998 American Institute of Physics. [S0021-9606(98)02137-0]. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Stranges, D (reprint author), Univ La Sapienza, Dipartimento Chim, PA Moro 5, I-00185 Rome, Italy. RI Yang, Xueming/C-8764-2013; Lee, Yuan-Tseh/F-7914-2012; OI STRANGES, Domenico/0000-0002-7003-4519 NR 69 TC 58 Z9 59 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 1 PY 1998 VL 109 IS 13 BP 5372 EP 5382 DI 10.1063/1.477156 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 123YF UT WOS:000076152700026 ER PT J AU Boyle, JS AF Boyle, JS TI Intercomparison of interannual variability of the global 200-hPa circulation for AMIP simulations SO JOURNAL OF CLIMATE LA English DT Article ID NORTHERN-HEMISPHERE WINTER; ATMOSPHERIC RESPONSE; MODEL; ANOMALIES; PATTERNS; TELECONNECTIONS; ROLES; FIELD AB The 200-hPa divergence and streamfunction from the 30 models of the Atmospheric Model Intercomparison Project (AMIP) are compared. The data used are in the form of monthly averages and are filtered to a spatial resolution of T10, although the actual spatial resolution of the models varies from R15 to T42. The tools of the analysis are principal components analysis (PCA) and common principal components (CPC). These analyses are carried out on the 120 months of data with the climatological annual cycle removed and in the case of the streamfunction with the zonal average also removed. The AMIP period (1979-88) encompasses two El Nino-Southern Oscillation (ENSO) events (1982-83 and 1986-87), and as could be expected the ENSO characteristic response has a prominent impact in the model simulations. The results indicate the following. 1) The PCA of the divergence has a dominant mode that is similar for all the models and has the signature of an ENSO response. It has an east-west dipole of divergence anomaly centered on the equator in the western Pacific. The streamfunction PC analysis also exhibits an ENSO-type response as the dominant mode, but this accounts for only 8%-21% of the variance. 2) The CPC analysis allows a direct comparison of the data from all the models on a common set of vectors. These results indicate that the models share a basic common pattern but there is a strong variation in the amplitude of the corresponding modes. There is less commonality in the higher components for the CPC streamfunction than seen in the divergence. This appears to be related to the stronger streamfunction response in the midlatitudes, which is presumably more affected by nonlinearity and intrinsic variability of the model integrations. 3) Based on results using an ensemble of five decadal runs using the European Centre for Medium-Range Forecasts (ECMWF) GCM an estimate is made of the variation of explained variance due to intrinsic variability for a single model. It is found that in general the intermodel variation is somewhat greater than the intramodel ensemble variation using the ECMWF model. 4) A probability density function (PDF) analysis in the space spanned by the first two CPCs for the velocity potential (which explain over 70% of the variance for all but one model) yields distinctive dynamical signatures. Some models populate a somewhat larger PDF space than others. There is an implication that the models differ beyond the variations due to intrinsic variability in the dynamical system. Some of the models have distinctly different responses to a common SST forcing. The disparate results indicate that consensus on the representation of the physics of the atmosphere has not been reached, and the present uncertainty in the parameterizations is greater than the intrinsic uncertainty of the model system as shown by ensemble simulations. C1 Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94550 USA. RP Boyle, JS (reprint author), Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Mail Stop L-264,POB 808, Livermore, CA 94550 USA. EM boyle@cobra.llnl.gov NR 34 TC 9 Z9 10 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD OCT PY 1998 VL 11 IS 10 BP 2505 EP 2529 DI 10.1175/1520-0442(1998)011<2505:IOIVOT>2.0.CO;2 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 130TM UT WOS:000076536500004 ER PT J AU Liu, SY Eary, JF Petersdorf, SH Martin, PJ Maloney, DG Appelbaum, FR Matthews, DC Bush, SA Durack, LD Fisher, DR Gooley, TA Bernstein, ID Press, OW AF Liu, SY Eary, JF Petersdorf, SH Martin, PJ Maloney, DG Appelbaum, FR Matthews, DC Bush, SA Durack, LD Fisher, DR Gooley, TA Bernstein, ID Press, OW TI Follow-up of relapsed B-cell lymphoma patients treated with iodine-131-labeled anti-CD20 antibody and autologous stem-cell rescue SO JOURNAL OF CLINICAL ONCOLOGY LA English DT Article ID BONE-MARROW TRANSPLANTATION; NON-HODGKINS-LYMPHOMA; TOTAL-BODY IRRADIATION; HIGH-DOSE THERAPY; LONG-TERM FOLLOW; MONOCLONAL-ANTIBODY; MYELODYSPLASTIC SYNDROME; FOLLICULAR LYMPHOMA; DRUG-THERAPY; RADIOIMMUNOTHERAPY AB Purpose: Radioimmunotherapy (RIT) is a promising treatment approach for B-cell lymphomas, This is our first opportunity to report long-term follow-vp data and late toxicities in 29 patients treated with myeloablative doses of iodine-131-anti-CD20 antibody (anti-B1) and autologous stem-cell rescue, Patients and Methods: Trace-labeled biodistribution studies first determined the ability to deliver higher absorbed radiation doses to tumor sites than to lung, liver, or kidney at varying amounts of anti-B1 protein (0.35, 1.7, or 7 mg/kg), Twenty-nine patients received therapeutic infusions of single-agent I-131-anti-B1, given at the protein dose found optimal in the biodistribution study labeled with amounts of I-131 (280 to 785 mCi [10.4 to 29.0 GBq]) calculated to deliver specific absorbed radiation doses to the normal organs, followed by autologous stem-cell support. Results: Major responses occurred in 25 patients (86%), with 23 complete responses (CRs; 79%), The nonhematopoietic dose-limiting toxicity was reversible cardiopulmonary insufficiency, which occurred in two patients at RIT doses that delivered greater than or equal to 27 Gy to the lungs. With a median follow-up time of 42 months, the estimated overall and progression free survival rates are 68% and 42%, respectively, Currently, 14 of 29 patients remain in unmaintained remissions that range from 27+ to 87+ months after RIT, Late toxicities have been uncommon except for elevated thyroid-stimulating hormone (TSH) levels found in approximately 60% of the subjects, Two patients developed second malignancies, but none have developed myelodysplasia (MDS), Conclusion: Myeloablative I-131-anti-BT RIT is relatively well tolerated when given with autologous stem-cell support and often results in prolonged remission durations with few late toxicities. (C) 1998 by American Society of Clinical Oncology. C1 Univ Washington, Med Ctr, Dept Med, Seattle, WA 98195 USA. Univ Washington, Dept Pediat, Seattle, WA 98195 USA. Univ Washington, Dept Radiol, Seattle, WA 98195 USA. Univ Washington, Dept Biol Struct, Seattle, WA 98195 USA. Univ Washington, Dept Biostat, Seattle, WA 98195 USA. Fred Hutchinson Canc Res Ctr, Seattle, WA 98104 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Press, OW (reprint author), Univ Washington, Med Ctr, Dept Med, Box 356043, Seattle, WA 98195 USA. FU NCI NIH HHS [P01CA44991] NR 48 TC 207 Z9 210 U1 0 U2 1 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0732-183X J9 J CLIN ONCOL JI J. Clin. Oncol. PD OCT PY 1998 VL 16 IS 10 BP 3270 EP 3278 PG 9 WC Oncology SC Oncology GA 127JJ UT WOS:000076347100009 PM 9779701 ER PT J AU Ewing, TF AF Ewing, TF TI Multimedia development software: Object-oriented interfaced-based simulation SO JOURNAL OF COMPUTING IN CIVIL ENGINEERING LA English DT Editorial Material C1 Argonne Natl Lab, Technol Devel Div, Argonne, IL 60439 USA. RP Ewing, TF (reprint author), Argonne Natl Lab, Technol Devel Div, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Ewing, Thomas/G-5396-2014 NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 USA SN 0887-3801 J9 J COMPUT CIVIL ENG JI J. Comput. Civil. Eng. PD OCT PY 1998 VL 12 IS 4 BP 257 EP 257 DI 10.1061/(ASCE)0887-3801(1998)12:4(257) PG 1 WC Computer Science, Interdisciplinary Applications; Engineering, Civil SC Computer Science; Engineering GA 125UK UT WOS:000076255300015 ER PT J AU Park, JW Rouleau, CM Lowndes, DH AF Park, JW Rouleau, CM Lowndes, DH TI Heteroepitaxial growth of n-type CdSe on GaAs(001) by pulsed laser deposition: studies of film-substrate interdiffusion and indium diffusion SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID AMPHOTERIC NATIVE DEFECTS; MOLECULAR-BEAM EPITAXY; DEPTH RESOLUTION; SEMICONDUCTORS; INTERFACE; MECHANISM; PROFILES; LAYER AB Epitaxial CdSe films were grown on (001)-oriented and 2 degrees-miscut GaAs wafers at platen temperatures (T(p)) of 250-425 degrees C by ArF (193 nm) pulsed excimer laser ablation of a stoichiometric CdSe target in vacuum and low-pressure Ar gas. The substrates were bonded to the platen with indium solder or silver paint. Auger electron spectroscopy (AES) combined with ion sputtering and energy dispersive X-ray fluorescent spectroscopy were employed to investigate him-substrate interdiffusion, the presence of indium or silver in the films, and CdSe film stoichiometry, all as functions of the him-growth conditions. Extensive interdiffusion took place at the film-substrate interface for CdSe films grown at T(p) greater than or equal to 355 degrees C but was greatly reduced at T(p) = 250 degrees C. Tilting the substrate to be approximately parallel to the ablation plume as well as increasing the ambient gas pressure also reduced film-substrate interdiffusion. Indium was found in films deposited at T(p) greater than or equal to 355 degrees C while no In was detected in films deposited at T(p) = 250 degrees C. AES depth profiling showed that the In concentration was highest at the CdSe Olm surface and that the Cd concentration varied inversely with the In concentration. At higher In concentrations the Se concentration also varied inversely with the In concentration in the near-surface region, implying that In clusters or interstitials may exist in addition to substitutional indium. In the absence of indium diffusion the CdSe films were nearly stoichiometric. No silver was found in any film. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Lowndes, DH (reprint author), Oak Ridge Natl Lab, Div Solid State, Bldg 3150,POB 2008, Oak Ridge, TN 37831 USA. EM vdh@ornl.gov RI Rouleau, Christopher/Q-2737-2015 OI Rouleau, Christopher/0000-0002-5488-3537 NR 28 TC 8 Z9 8 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD OCT PY 1998 VL 193 IS 4 BP 516 EP 527 DI 10.1016/S0022-0248(98)00544-2 PG 12 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 134CJ UT WOS:000076725000011 ER PT J AU Haarmann, TK AF Haarmann, TK TI Honey bees (Hymenoptera : Apidae) as indicators of radionuclide contamination: Investigating contaminant redistribution using concentrations in water, flowers, and honey bees SO JOURNAL OF ECONOMIC ENTOMOLOGY LA English DT Article DE Apis mellifera; honey bees; contamination; bioaccumulation; ecotoxicology; radionuclides ID LOS-ALAMOS; POLLUTION; COLONIES; PRODUCTS; METALS AB As part of ongoing research concerning the use of honey bees, Apis mellifera L., as indicators of environmental radionuclide contamination, samples of water, flowers, and honey Lees were collected for 2 consecutive years. The samples were collected within a study site containing radionuclide contamination above background levels. The samples were analyzed for concentrations of radionuclides, and the results were compared using rank sum, correlation, and trend analysis. Results were then used to assess the redistribution pathway of radionuclides within the study site. Results indicate that honey bees receive the majority of their contamination directly from the source, a radioactive waste lagoon. The amount of contamination the honey Lees receive from flowers during nectar collection appears to be insignificant compared to the amount received. during water collection. Results did not demonstrate significant patterns of correlation or trend between the lagoon, bees, or flowers. Sample results showed a significant bioaccumulation of cobalt-60 and sodium-22 within the honey Lees but no significant bioaccumulation within the flowers. C1 Univ Calif Los Alamos Natl Lab, Ecol Studies Team, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Biol, Albuquerque, NM 87131 USA. RP Haarmann, TK (reprint author), Univ Calif Los Alamos Natl Lab, Ecol Studies Team, POB 1663, Los Alamos, NM 87545 USA. NR 29 TC 0 Z9 0 U1 2 U2 6 PU ENTOMOL SOC AMER PI LANHAM PA 9301 ANNAPOLIS RD, LANHAM, MD 20706 USA SN 0022-0493 J9 J ECON ENTOMOL JI J. Econ. Entomol. PD OCT PY 1998 VL 91 IS 5 BP 1072 EP 1077 PG 6 WC Entomology SC Entomology GA 134JA UT WOS:000076738700010 ER PT J AU Darab, JG Matson, DW AF Darab, JG Matson, DW TI Continuous hydrothermal processing of nano-crystalline particulates for chemical-mechanical planarization SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT TMS Annual Meeting CY FEB 15-19, 1998 CL SAN ANTONIO, TX SP TMS DE hydrothermal processing; iron oxide; nano-crystalline particulates; titanium oxide; zirconium oxide ID CARBON BOND SCISSION; NAPHTHYLBIBENZYLMETHANE; POWDER; ZRO2 AB A wide range of nano-crystalline, single and multi-component oxide/oxyhydroxide particulates, which may be potentially useful as abrasives for chemical-mechanical planarization (CMP) processes, have been produced using a novel, flow-through hydrothermal technology previously developed at the Pacific Northwest National Laboratory. The process, termed rapid thermal decomposition of precursors in solution (RTDS), converts aqueous feed stock solutions containing metal salts and other thermally activated reactants into suspensions or slurries of nano-crystals (with diameters of generally less than 30 nm) by continuous flow through a heated, high pressure reaction pipe (typically, 200-400 degrees C, 6000-8000 psi). Flow at pressure is maintained using a nozzle at the down-stream end of the reaction tube. Crystallite formation occurs during the solution's brief residence time (<30 a) in the reaction pipe. Control over crystalline phase and, in some cases, particle morphology call be tailored by selecting the appropriate feed chemistry and processing conditions. Using bench-scale equipment, RTDS is capable of producing nano-crystalline particulate material at rates of up to approximate to 500 gm of solids per hour. The RTDS processing and characterization of nanocrystalline zirconium-, titanium-, and iron-based oxide and oxyhydroxide particulates are reviewed. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Darab, JG (reprint author), Pacific NW Lab, POB 999,MS K3-59, Richland, WA 99352 USA. EM jg_darab@pnl.gov NR 17 TC 12 Z9 12 U1 2 U2 13 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD OCT PY 1998 VL 27 IS 10 BP 1068 EP 1072 DI 10.1007/s11664-998-0139-7 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 128NL UT WOS:000076412800002 ER PT J AU Oji, LN AF Oji, LN TI Mercury disposal via sulfur reactions SO JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE LA English DT Article AB A high-shear blending technique for converting large volumes of elemental mercury into mercuric sulfides has been evaluated. The two basic forms of mercuric sulfide (cinnabar and metacinnabar) were prepared by triturating stoichiometric ratios of elemental mercury and sulfur. X-ray analysis and scanning electron microscope techniques confirm the existence of both forms of mercuric sulfide. These sulfides passed the Toxicity Characteristic Leaching Procedure test for mercury vapor-phase requirements and thus meet waste, acceptance criteria for handling/storage of low-level radioactively contaminated mercury. Black mercuric sulfide (metacinnabar) is the recommended target product in the conversion of mercury to mercuric sulfide, because it is easier and safer to produce. Zinc-mercury amalgams were also prepared and compared with the sulfides in terms of meeting processing and storage requirements for mercury mixed waste. Mercury loading for both forms of mercuric sulfide is significantly higher than mercury loading in a typical transition metal amalgam. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Oji, LN (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Build 773-43 A, Aiken, SC 29808 USA. NR 6 TC 14 Z9 16 U1 2 U2 6 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 USA SN 0733-9372 J9 J ENVIRON ENG-ASCE JI J. Environ. Eng.-ASCE PD OCT PY 1998 VL 124 IS 10 BP 945 EP 952 DI 10.1061/(ASCE)0733-9372(1998)124:10(945) PG 8 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 121XB UT WOS:000076040200008 ER PT J AU Kramer, JA Adams, MD Singh, GB Doggett, NA Krawetz, SA AF Kramer, JA Adams, MD Singh, GB Doggett, NA Krawetz, SA TI Extended analysis of the region encompassing the PRM1 -> PRM2 -> TNP2 domain: Genomic organization, evolution and gene identification SO JOURNAL OF EXPERIMENTAL ZOOLOGY LA English DT Article; Proceedings Paper CT 9th International Congress on Isozymes, Genes, and Gene Families CY APR 14-19, 1997 CL SAN ANTONIO, TEXAS ID NUCLEAR MATRIX; PROTAMINE GENES; EXPRESSED GENE; SEQUENCE; CLUSTER; CDNA; TRANSITION; INTRONLESS; ALIGNMENT; PATTERNS AB The human male haploid expressed protamine 1 (PRM1) -->protamine 2 (PRM2) -->transition protein 2 (TNP2) locus comprises a coordinately regulated multigenic domain. This region of 16p13.13 has been used as a model to address how the organization of genes and genic domains within the human genome may influence tissue specific gene expression. Toward this goal, we have completed an extensive computational and biological analysis of the region encompassing the PRM1-->PRM2-->TNP2 domain. These analyses have revealed the likely genesis of this domain. Interestingly, the SOCS-1 gene and an hnRNP C-class pseudogene lies just 3' of this domain. Regions of nuclear matrix attachment also mark these newly identified genes. J. Exp. Zool. 282:245-253, 1998. (C) 1998 Wiley-Liss, Inc. C1 Wayne State Univ, Sch Med, Dept Obstet & Gynecol, Detroit, MI 48202 USA. Wayne State Univ, Sch Med, Ctr Mol Med & Genet, Detroit, MI 48202 USA. Inst Genome Res, Rockville, MD 20850 USA. Natl Ctr Genome Resources, Bioinformat Algorithms Res Div, Santa Fe, NM 87505 USA. Univ Calif Los Alamos Natl Lab, Ctr Human Genome Studies, Los Alamos, NM 87545 USA. RP Krawetz, SA (reprint author), Wayne State Univ, Sch Med, Dept Obstet & Gynecol, 275 E Hancock, Detroit, MI 48202 USA. NR 26 TC 19 Z9 19 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0022-104X J9 J EXP ZOOL JI J. Exp. Zool. PD OCT 1 PY 1998 VL 282 IS 1-2 BP 245 EP 253 DI 10.1002/(SICI)1097-010X(199809/10)282:1/2<245::AID-JEZ26>3.3.CO;2-H PG 9 WC Zoology SC Zoology GA 112CQ UT WOS:000075476900026 PM 9723181 ER PT J AU Jahn, JM LaBelle, J AF Jahn, JM LaBelle, J TI Rocket measurements of high-altitude spread F irregularities at the magnetic dip equator SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID COLLISIONAL INTERCHANGE INSTABILITY; LARGE-SCALE MEASUREMENTS; NUMERICAL SIMULATIONS; STEEPENED STRUCTURES; ELECTRON-DENSITY; IONOSPHERE; PROBE; TURBULENCE; CAMPAIGN; BUBBLES AB We present the first rocket measurements of equatorial spread F irregularities at altitudes significantly above 600 km, in what is believed to be the inertially dominated regime of spread F. On October 14, 1994, at 1955 LT (2255 UT) a Black Brant X rocket instrumented to measure plasma density and electric fields was launched from Alcantara, Braxil (2 degrees 18.75' S, 44 degrees 22.3' W, dip angle 1.5 degrees at 300 km altitude), into active topside spread F plumes. On upleg the payload remained continuously in these plumes up to an altitude of 822 km. Power spectra of electron density fluctuations show characteristic dual-power law behavior with spectral indices of -1.7 at frequencies below 60 Hz and -5 at frequencies above 60 Hz. Shocklike coherent structures characterized the density waveforms. The electric field fluctuations had spectral indices ranging from -3 to -4. We observe no evidence of altitude variation in the spectral indices or in the density fluctuation waveforms. Over the entire altitude range of the observations, 350-822 km, the data remain in agreement with previous measurements of collisional spread F below 600 km. C1 Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. RP Jahn, JM (reprint author), Univ Calif Los Alamos Natl Lab, NIS-2,MS D436, Los Alamos, NM 87545 USA. EM jm@lanl.gov; jlabelle@einstein.dart-mouth.edu NR 38 TC 18 Z9 18 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD OCT 1 PY 1998 VL 103 IS A10 BP 23427 EP 23441 DI 10.1029/97JA02636 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 125XL UT WOS:000076262300009 ER PT J AU Nagai, T Fujimoto, M Nakamura, R Saito, Y Mukai, T Yamamoto, T Nishida, A Kokubun, S Reeves, GD Lepping, RP AF Nagai, T Fujimoto, M Nakamura, R Saito, Y Mukai, T Yamamoto, T Nishida, A Kokubun, S Reeves, GD Lepping, RP TI Geotail observations of a fast tailward flow at X-GSM=-15 R-E SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SUBSTORM GROWTH-PHASE; MAGNETOTAIL; ONSET; PSEUDOBREAKUP; PARTICLE AB Geotail observed a fast tailward flow burst (a speed of >600 km/s) with southward B-z in the Earth's magnetotail at a radial distance of 15.5 R-E on March 30, 1995. Ions in this burst consisted of a single-component plasma showing convection motion, and these ions were confined near the neutral sheet. This flow burst was likely associated with a pseudobreakup rather than a major substorm onset. In this event, magnetic reconnection appeared to take place only for the field lines near the neutral sheet. The magnetic reconnection was quenched soon and resulted in a short-lived tailward flow burst embedded in the plasma sheet. C1 Tokyo Inst Technol, Dept Earth & Planetary Sci, Tokyo 1528551, Japan. Nagoya Univ, Solar Terr Environm Lab, Toyokawa 4428507, Japan. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Nagai, T (reprint author), Tokyo Inst Technol, Dept Earth & Planetary Sci, Tokyo 1528551, Japan. EM nagai@geo.titech.ac.jp RI Nakamura, Rumi/I-7712-2013; Reeves, Geoffrey/E-8101-2011 OI Nakamura, Rumi/0000-0002-2620-9211; Reeves, Geoffrey/0000-0002-7985-8098 NR 15 TC 22 Z9 22 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD OCT 1 PY 1998 VL 103 IS A10 BP 23543 EP 23550 DI 10.1029/98JA02246 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 125XL UT WOS:000076262300016 ER PT J AU Denton, RE Lessard, MR LaBelle, JW Gary, SP AF Denton, RE Lessard, MR LaBelle, JW Gary, SP TI Identification of low-frequency magnetosheath waves SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID PLASMA DEPLETION LAYER; EARTHS BOW SHOCK; ISEE 1-2; FLUCTUATIONS; MAGNETOPAUSE; MIRROR; MODES; INSTABILITIES; IRM AB Four low-frequency modes may propagate in a, high-beta, nearly bi-Maxwellian plasma, the magnetosonic, Alfven, ion acoustic, and mirror modes. This study uses a procedure based on Linear Vlasov theory for the identification of these modes by use of transport ratios, dimensionless ratios of the fluctuating field and plasma quantities. A single parameter, the mode, deviation, is calculated which characterizes the difference between the theoretical transport ratios of a particular mode and the observed ratios. As well as determining the mode that best describes the observed fluctuations, it gives us a measure of whether or not the resulting identification is unique, Unfortunately, a unique identification is not always possible because of problems discussed herein. One problem is that the parallel phase ratio (related to the phase angle between density and parallel magnetic fluctuations) is often not well defined. Using the plasma and magnetic field data gathered by the Active Magnetospheric Particle Tracer Explorers/Ion Release Module spacecraft, we calculate the mode deviations and identify the modes observed in the magnetosheath. The quasi-perpendicular (with wave vector at a large angle to the background magnetic field) mirror mode is clearly identified in the inner (close to the magnetopause) and middle magnetosheath. The quasi-parallel mirror mode may be observed in the inner magnetosheath, but that identification is not certain. Alfven-like modes are observed for one event in the outer magnetosheath (near the bow shock) and are probably observed in two others. C1 Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Denton, RE (reprint author), Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. NR 26 TC 15 Z9 15 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD OCT 1 PY 1998 VL 103 IS A10 BP 23661 EP 23676 DI 10.1029/98JA02196 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 125XL UT WOS:000076262300025 ER PT J AU Lawrence, CM Nelson, DV Bennett, TE Spingarn, JR AF Lawrence, CM Nelson, DV Bennett, TE Spingarn, JR TI An embedded fiber optic sensor method for determining residual stresses in fiber-reinforced composite materials SO JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES LA English DT Article ID TEMPERATURE; MECHANICS; CURE AB A method to determine process-induced residual stress in fiber-reinforced composite materials using strain measurements from embedded fiber optic sensors is presented. This method allows non-destructive, real-time determination of residual macrostress in these materials and may be useful for both process monitoring and control. Extrinsic Fabry-Perot interferometer strain sensors were embedded in Hercules AS4/3501-6 graphite/epoxy composite specimens prior to cure. The specimens were cured in a press, and the internal strains and temperatures developed during processing were monitored and recorded. Residual macrostresses were computed from these measurements using a viscoelastic model of the material. The results compare favorably with analytical predictions, previous experimental measurements from a destructive technique, and with measurements of warpage of a non-symmetric laminate. C1 Stanford Univ, Dept Engn Mech, Stanford, CA 94305 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Nelson, DV (reprint author), Stanford Univ, Dept Engn Mech, Stanford, CA 94305 USA. NR 30 TC 19 Z9 19 U1 0 U2 1 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 1045-389X J9 J INTEL MAT SYST STR JI J. Intell. Mater. Syst. Struct. PD OCT PY 1998 VL 9 IS 10 BP 788 EP 799 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 248YE UT WOS:000083303700002 ER PT J AU Sanders, PG Leong, KH Keske, JS Kornecki, G AF Sanders, PG Leong, KH Keske, JS Kornecki, G TI Real-time monitoring of laser beam welding using infrared weld emissions SO JOURNAL OF LASER APPLICATIONS LA Welsh DT Article DE laser beam welding; infrared; process monitoring; weld penetration AB A nonintrusive, solid-state device has been developed to monitor in real time the infrared emissions during laser welding. The weld monitor output is an analog signal (100-1000 mV) that depends on the beam power and weld characteristics. The de level of this signal is related to weld penetration, while ac portions of the output can be correlated with surface irregularities and part misalignment or contamination. Changes in de behavior are also noted for both full and deep penetration welds. Full penetration welds are signified by an abrupt reduction in the weld monitor output. Bead-on-plate welds were made on steel, aluminum, and magnesium with both a cw CO2 laser and a pulsed Nd:YAG laser to explore the relationships between the weld characteristics and the weld monitor output. (C) 1998 Laser Institute of America. C1 Argonne Natl Lab, Technol Dev Div, Argonne, IL 60439 USA. RP Sanders, PG (reprint author), Argonne Natl Lab, Technol Dev Div, Argonne, IL 60439 USA. NR 11 TC 12 Z9 13 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1042-346X J9 J LASER APPL JI J. Laser Appl. PD OCT PY 1998 VL 10 IS 5 BP 205 EP 211 PG 7 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA 125FE UT WOS:000076226100003 ER PT J AU Payne, SA Bibeau, C AF Payne, SA Bibeau, C TI Picosecond nonradiative processes in neodymium-doped crystals and glasses: Mechanism for the energy gap law SO JOURNAL OF LUMINESCENCE LA English DT Article DE nonradiative decay; Nd-doped materials; energy-gap law ID RARE-EARTH IONS; MULTIPHONON RELAXATION; LEVEL LIFETIME; ND-3+; ABSORPTION; FLUORIDE; RATES; MODEL AB We present measurements of the (4)G(7/2) emission lifetime for 26 Nd-doped crystals and glasses, including phosphates, silicates, oxides, garnets, apatites, and fluorides. The fluorescent decays were found to range from 70 ps to 41 ns, depending on the host medium. We show that the (4)G(7/2) emission lifetime is correlated to the I-4(11/2) relaxation time to within a factor of two, by comparing the present results with previous directly-determined I-4(11/2) lifetimes. This (4)G(7/2) - I-4(11/2) correlation is useful because the I-4(11/2) state is the terminal level for the common 1.06 mu m Nd-laser transition, while the (4)G(7/2) emission time can be measured in a relatively straightforward manner. A model of nonradiative decay based on dipole-dipole energy transfer is developed and found to be supported by our data. It allows independent calculation of the parameters of the energy gap law, in addition to fitting the nonradiative lifetime data. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, POB 5508,L-490, Livermore, CA 94550 USA. EM payne2@llnl.gov NR 46 TC 30 Z9 31 U1 1 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 EI 1872-7883 J9 J LUMIN JI J. Lumines. PD OCT PY 1998 VL 79 IS 3 BP 143 EP 159 DI 10.1016/S0022-2313(98)00037-4 PG 17 WC Optics SC Optics GA 137FD UT WOS:000076903400001 ER PT J AU Cooke, DW Muenchausen, RE Bennett, BL McClellan, KJ Portis, AM AF Cooke, DW Muenchausen, RE Bennett, BL McClellan, KJ Portis, AM TI Temperature-dependent luminescence of cerium-doped ytterbium oxyorthosilicate SO JOURNAL OF LUMINESCENCE LA English DT Article DE Yb2SiO5 : Ce; radioluminescence; charge transfer; scintillators ID SCINTILLATOR AB We have measured optical absorption and radioluminescence of Yb1.999Ce0.001SiO5 (YbSO) and found it to be a very poor phosphor. This is in striking contrast to Lu-, Y-, and Gd-based oxyorthosilicates, which are characterized by very strong Ce3+ emission. The absence of luminescence in YbSO is due to quenching of the Ce3+ emission via an [Yb2+-Ce4+] charge-transfer mechanism. Extremely weak band emission observed in YbSO is attributed to transitions connecting the (Yb2+-h(+)) charge-transfer state to the two levels of the Yb2+ 4f(13) configuration. Optical absorption shows the usual bands due to Ce3+ absorption with a band edge near 260 nm. The RL emission spectrum consists of a well-resolved band near 500 nm and an additional band in the region 260-300 nm. The exact position of the latter band cannot be determined due to concomitant Ce3+ absorption. At room temperature the YbSO RL emission is ca. six orders of magnitude weaker than Lu2SiO5 : Ce (LSO) emission. Maximum intensity in the interval 8-300 K occurs near 40 K and is ca. four orders of magnitude weaker than LSO emission. The YbSO band emission is thermally quenched with increasing temperature (40-300 K), consistent with classical theory predictions. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Sci Mat, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Cooke, DW (reprint author), Univ Calif Los Alamos Natl Lab, Div Sci Mat, MST-8,MS E546, Los Alamos, NM 87545 USA. NR 16 TC 21 Z9 21 U1 3 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 J9 J LUMIN JI J. Lumines. PD OCT PY 1998 VL 79 IS 3 BP 185 EP 190 DI 10.1016/S0022-2313(98)00042-8 PG 6 WC Optics SC Optics GA 137FD UT WOS:000076903400004 ER PT J AU Liu, HP James, P Broddefalk, A Andersson, Y Granberg, P Eriksson, O AF Liu, HP James, P Broddefalk, A Andersson, Y Granberg, P Eriksson, O TI Structural and magnetic properties of (Fe1-xCox)(3)P compounds: experiment and theory SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE magnetism; crystal structure; first principles calculations; neutron scattering experiments; magnetisation measurements ID BRILLOUIN-ZONE; SPECIAL POINTS; BAND THEORY; SYSTEMS AB The structural and magnetic properties of (Fe1 - xCox)(3)P compounds have been investigated by means of X-ray and neutron diffraction experiments, magnetization measurements and first-principles calculations. The saturation magnetization and the transition temperature of (Fe1 - xCox)(3)P decrease with increasing Co concentration. The magnetic moments on the three non-equivalent metal sites are determined in detail by means of neutron diffraction experiments and first principles calculations which both show that the moments on the different sites have different magnitudes and they all decrease with increasing Co concentration. Results show that Co preferentially substitutes Fe on two of the metal sites. The complex behavior of the individual magnetic moments and the site preferences of Co substitution are discussed in terms of atomic radius, coordination numbers, and eigenvalue sums. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Uppsala Univ, Dept Inorgan Chem, SE-75121 Uppsala, Sweden. Uppsala Univ, Dept Phys, Condensed Matter Theory Grp, SE-75121 Uppsala, Sweden. Uppsala Univ, Dept Mat Sci, SE-75121 Uppsala, Sweden. Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87544 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87544 USA. RP Uppsala Univ, Dept Inorgan Chem, Box 538, SE-75121 Uppsala, Sweden. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 28 TC 12 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 EI 1873-4766 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD OCT PY 1998 VL 189 IS 1 BP 69 EP 82 DI 10.1016/S0304-8853(98)00203-0 PG 14 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 126CJ UT WOS:000076275000010 ER PT J AU Shield, JE Li, CP Branagan, DJ AF Shield, JE Li, CP Branagan, DJ TI Microstructures and phase formation in rapidly solidified Sm-Fe and Sm-Fe-Ti-C alloys SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE microstructure; interstitial permanent magnets; rapid solidification; magnetic properties ID MAGNETIC-PROPERTIES; INTERMETALLIC COMPOUNDS; NITRIDES AB Partially ordered Sm2Fe17, closer to the SmFe7 structure, formed upon melt spinning of Sm11Fe89. A strong dependence of grain size on the wheel speed was also observed, with wheel speeds less than 40 m/s generating grain sizes above the single domain limit for Sm2Fe17Nx. The addition of Ti and C resulted in an order of magnitude grain refinement compared to the binary alloys. The Ti and C also effectively inhibited grain growth during annealing. The nitrided Sm-Fe-Ti-C alloys also displayed a rapid decrease in coercivity with decreasing grain size, which was attributed to increased exchange interactions. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Shield, JE (reprint author), Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. EM jeffrey.shield@mse.utah.edu NR 13 TC 21 Z9 24 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD OCT PY 1998 VL 188 IS 3 BP 353 EP 360 DI 10.1016/S0304-8853(98)00208-X PG 8 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 121JT UT WOS:000076011000011 ER PT J AU Gschneidner, KA AF Gschneidner, KA TI Preparation and processing of rare earth chalcogenides SO JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE LA English DT Article DE mechanical alloy of rare earth sulfides; mechanical milling of pare earth sulfides; preparation of rare earth chalcogenides; processing of rare earth chalcogenides; rare earth chalcogenides; rare earth sulfide ID THERMOELECTRIC PROPERTIES; ALLOYS; LESS AB Rare earth chalcogenides are initially prepared by a direct combination of the pure rare earth metal and the pure chalogen element with or without a catalyst. The use of iodine (10 to 100 mg) as a fluxing agent (catalyst), especially to prepare heavy lanthanide chalcogenides, greatly speeds up the formation of the rare earth chalcogenide. The resultant powders are consolidated by melting, pressure assisted sintering (PAS), or pressure assisted reaction sintering (PARS) to obtain near theoretical density solids, Mechanical alloying is a useful technique for preparing ternary alloys. In addition, mechanical alloying and mechanical milling can be used to form metastable allotropic forms of the yttrium and heavy lanthanide sulfides. Chemical analysis techniques are also described because it is strongly recommended that samples prepared by melting should have their chemical compositions verified because of chalogen losses in the melting step. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Gschneidner, KA (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 18 TC 13 Z9 13 U1 3 U2 13 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9495 J9 J MATER ENG PERFORM JI J. Mater. Eng. Perform. PD OCT PY 1998 VL 7 IS 5 BP 656 EP 660 DI 10.1361/105994998770347521 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 124YP UT WOS:000076210600010 ER PT J AU Kazmerski, LL AF Kazmerski, LL TI Photovoltaics characterization: A survey of diagnostic measurements SO JOURNAL OF MATERIALS RESEARCH LA English DT Review ID MINORITY-CARRIER LIFETIME; III-V-SEMICONDUCTORS; ELECTRON-EMISSION; ION-BOMBARDMENT; MICROSCOPY; SURFACE; SPECTROSCOPY; SILICON; DEVICES; WAFERS AB The advancement of the photovoltaic technology is closely linked to the standard evaluation of the product, the diagnosis of problems, the validation of materials and cell properties, and the engineering and documentation of the ensemble of device properties from internal interfaces through power outputs. The focus of this paper is on some of the more common, visible, and important techniques dealing with physical-chemical through electro-optical parameters, which are linked intimately to the performance quality of materials and devices. Two areas, defined by their spatial-resolution qualities, are emphasized: macroscale and microscale measurement technologies. The importance, strengths, and limitations of these techniques are stressed, especially their significance to photovoltaics. Included are several techniques that have been developed specifically to address problems and requirements for photovoltaics. The regime of measurement literally covers arrays through atoms. C1 Natl Renewable Energy Lab, Ctr Measurement & Characterizat, Golden, CO 80401 USA. RP Kazmerski, LL (reprint author), Natl Renewable Energy Lab, Ctr Measurement & Characterizat, Golden, CO 80401 USA. NR 174 TC 8 Z9 8 U1 0 U2 5 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 OCT PY 1998 VL 13 IS 10 BP 2684 EP 2708 DI 10.1557/JMR.1998.0372 PG 25 WC Materials Science, Multidisciplinary SC Materials Science GA 127QM UT WOS:000076362100002 ER PT J AU Kiely, JD Bonnell, DA AF Kiely, JD Bonnell, DA TI Metal ceramic interface toughness I: Plasticity on multiple length scales SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID DRILLED COMPRESSION SPECIMEN; FRACTURE ENERGY; DIFFUSION; IMPURITIES; BICRYSTALS; RESISTANCE AB The fracture toughness of Ni-sapphire interfaces was measured as a function of interfacial embrittlement, Embrittlement was controlled by segregating sulfur to the interface, by limiting the presence of moist air in the test environment, and by altering the distribution of interfacial particulates. Fracture energies scaled with the degree of embrittlement and ranged from 8.5 to 34.2 J/m(2). Scanning probe microscopy revealed four distinct plasticity features, the heights of which ranged from 1 mu m to 0.5 nm. Plasticity generation processes are determined based on the variation of feature height and position with fracture energy, allowing features associated with the interface decohesion process to be identified. C1 Univ Penn, Philadelphia, PA 19104 USA. RP Kiely, JD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 26 TC 6 Z9 6 U1 0 U2 0 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 OCT PY 1998 VL 13 IS 10 BP 2871 EP 2880 DI 10.1557/JMR.1998.0393 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 127QM UT WOS:000076362100023 ER PT J AU Kiely, JD Bonnell, DA AF Kiely, JD Bonnell, DA TI Metal ceramic interface toughness II: Mechanisms of fracture and energy dissipation SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CRACK-TIP FIELDS; BIMATERIAL INTERFACES; CLEAVAGE FRACTURE; PLASTIC-FLOW; MODEL; RESISTANCE; ALUMINA AB Based on observations of plasticity on fracture surfaces, we propose two fracture mechanism for Ni-sapphire interfaces. A brittle-type mechanism is proposed for the decohesion of Ni from sapphire by which cracks advance in increments of 20 nm. When particulates that increase the interface strength are present, debonding occurs at the leading edge of the particulate, and unsteady crack advance occurs. Additionally, toughening mechanisms are proposed for each type of plasticity feature observed, and the fracture energy of each mechanism is quantified. Comparison of energy dissipated by these mechanisms with measured fracture energies indicates how the fracture energy of the interface varies with sulfur segregation and environmental embrittlement. C1 Univ Penn, Philadelphia, PA 19104 USA. RP Kiely, JD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 40 TC 1 Z9 1 U1 1 U2 2 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 OCT PY 1998 VL 13 IS 10 BP 2881 EP 2887 DI 10.1557/JMR.1998.0394 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 127QM UT WOS:000076362100024 ER PT J AU Vaudin, MD Rupich, MW Jowett, M Riley, GN Bingert, JF AF Vaudin, MD Rupich, MW Jowett, M Riley, GN Bingert, JF TI A method for crystallographic texture investigations using standard x-ray equipment SO JOURNAL OF MATERIALS RESEARCH LA English DT Article AB A fast and accurate method has been developed for measuring crystalline texture in homogeneous materials. The method uses a conventional powder x-ray diffractometer capable of theta scans. Two scans are recorded from the sample: first, a high resolution theta-2 theta scan is obtained of a Bragg peak whose diffracting planes are normal to the preferred orientation direction; second, a theta scan is obtained using this peak. The theta scan contains the required texture information, but the intensities must be corrected for defocusing and absorption to obtain the texture profile. The theta-2 theta scan of the Bragg peak is used to make the defocusing correction, and first principles calculations are used to correct for absorption. The theory behind these corrections is presented here. The validity of the technique has been verified by making measurements on untextured alumina. Data obtained from Bi2Sr2Ca2Cu3O10 superconducting tape specimens with this technique are compared with texture data obtained with a four-circle diffractometer. C1 NIST, Div Ceram, Gaithersburg, MD 20899 USA. Amer Superconductor Corp, Westborough, MA 01581 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Vaudin, MD (reprint author), NIST, Div Ceram, Gaithersburg, MD 20899 USA. NR 9 TC 33 Z9 33 U1 0 U2 7 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 OCT PY 1998 VL 13 IS 10 BP 2910 EP 2919 DI 10.1557/JMR.1998.0398 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 127QM UT WOS:000076362100028 ER PT J AU Igawa, N Nagasaki, T Ishii, Y Noda, K Ohno, H Morii, Y Fernandez-Baca, JA AF Igawa, N Nagasaki, T Ishii, Y Noda, K Ohno, H Morii, Y Fernandez-Baca, JA TI Phase-transformation study of metastable tetragonal zirconia powder SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID NORMAL GRAIN-GROWTH; MICROSTRUCTURE; CERAMICS; METALS AB The rate of the transformation from the metastable tetragonal to the monoclinic phase of ZrO2 was measured in air from 850 degrees C to 1000 degrees C by neutron diffraction. This rate was found to be temperature dependent, and its measured values were considerably lower then those reported previously. The kinetics of this phase transformation is discussed in terms of a modified 'crystallite growth-martensitic transformation model' that includes the distribution of crystallite sizes. (C) 1998 Kluwer Academic Publishers. C1 Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Igawa, N (reprint author), Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 15 TC 6 Z9 6 U1 1 U2 3 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 OCT 1 PY 1998 VL 33 IS 19 BP 4747 EP 4758 DI 10.1023/A:1004449407070 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 170XY UT WOS:000078833400013 ER PT J AU Sams, RL Blake, TA Sharpe, SW Flaud, JM Lafferty, WJ AF Sams, RL Blake, TA Sharpe, SW Flaud, JM Lafferty, WJ TI High-resolution infrared study of the nu(14), nu(17), and nu(18) bands of (B2H6)-B-11 and (BBH6)-B-10-B-11 SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID DIBORANE AB Using high-resolution Fourier transform spectra, a thorough analysis of the nu(14) c-type, nu(17) a-type, and nu(18) a-type bands of both (B2H6)-B-11 and (BBH6)-B-10-B-11 has been carried in the 10.3-, 6.2-, and 8.5-mu m spectral regions, respectively. From this analysis a large set of precise ground state combination differences with J values up to 36 (31) and K-a values extending to 18 (18) was derived for (B2H6)-B-11((BBH6)-B-10-B-11), These data were fitted using a Watson-type Hamiltonian leading to accurate ground state rotational constants. An r(s) value for the B-B distance has been determined to be 1.7645(10) Angstrom. The determination of upper state Hamiltonian constants proved to be much more difficult since the corresponding rotational levels of each of the bands are strongly perturbed by nearby dark states. To account for these strong localized resonances, it was necessary to introduce the relevant interacting terms in the Hamiltonian matrix. As a result it was possible to calculate the upper state energy levels quite satisfactorily. From these fits, estimates of the band centers and a few of the rotational constants of the resonating dark states were obtained. (C) 1998 Academic Press. C1 Pacific NW Lab, Richland, WA 99352 USA. Univ Paris 11, CNRS, Photophys Mol Lab, F-91405 Orsay, France. CSIC, Inst Estructura Mat, E-28006 Madrid, Spain. NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Sams, RL (reprint author), Pacific NW Lab, POB 999,Battelle Blvd, Richland, WA 99352 USA. NR 17 TC 10 Z9 10 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD OCT PY 1998 VL 191 IS 2 BP 331 EP 342 DI 10.1006/jmsp.1998.7649 PG 12 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 128CN UT WOS:000076387800014 ER PT J AU Magruder, RH Weeks, RA Weller, RA Zuhr, RA Hensley, DK AF Magruder, RH Weeks, RA Weller, RA Zuhr, RA Hensley, DK TI Formation and photosensitivity of defects in Se implanted silica SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT Glass and Optical Materials Division / Bragg Gratings, Photosensitivity and Poling in Glass Fibers and Waveguides - Applications and Fundamentals Meeting CY OCT 25-31, 1997 CL WILLIAMSBURG, VIRGINIA SP Amer Ceramic Soc, Optical Soc Amer (OSA), BGPP, IEEE/Laser & Electro-Soc, Corning Inc, Honeywell Inc, Fed Highway Adm, Colonial Williamsburg Fdn ID ION-IMPLANTATION; FUSED-SILICA; SIXSE1-X GLASSES; INDEX CHANGES; SISE2 AB Silica was implanted with Se ions at 4 MeV with nominal doses of 0.1, 0.3, 0.5, 1.0 and 3.0 x 10(16) ions/cm(2). The optical absorption was measured from 1.8 to 6.2 eV. Bands at 5.9 and 5 eV are observed in the absorption spectra, The magnitude of the absorption increases with increasing dose but the increase is variant with dose. Bands at 2.6, 3.7 and 4.8 eV are attributed to the presence of the Se. The 0.3 and 1.0 x 10(16) samples were exposed to 5 eV KrF excimer irradiation with a fluence of 150 mJ/cm(2) per pulse for pulse totals of 1.5 J/cm(2). Bleaching of the 5 and 5.9 eV bands is observed and is attributed to the bleaching of defects at 5, 5.5 and 5.9 eV. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Belmont Univ, Dept Chem & Phys, Nashville, TN 37212 USA. Vanderbilt Univ, Dept Appl & Engn Sci, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Magruder, RH (reprint author), Belmont Univ, Dept Chem & Phys, 1900 Belmont Blvd, Nashville, TN 37212 USA. EM magruder@mail.belmont.edu RI Hensley, Dale/A-6282-2016 OI Hensley, Dale/0000-0001-8763-7765 NR 14 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD OCT PY 1998 VL 239 IS 1-3 BP 78 EP 83 DI 10.1016/S0022-3093(98)00722-4 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 133YJ UT WOS:000076714900007 ER PT J AU Simmons-Potter, K Potter, BG Meister, DC Sinclair, MB AF Simmons-Potter, K Potter, BG Meister, DC Sinclair, MB TI Photosensitive thin film materials and devices SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT Glass and Optical Materials Division / Bragg Gratings, Photosensitivity and Poling in Glass Fibers and Waveguides - Applications and Fundamentals Meeting CY OCT 25-31, 1997 CL WILLIAMSBURG, VIRGINIA SP Amer Ceramic Soc, Optical Soc Amer (OSA), BGPP, IEEE/Laser & Electro-Soc, Corning Inc, Honeywell Inc, Fed Highway Adm, Colonial Williamsburg Fdn ID OPTICAL FIBERS; GLASS-FILMS; WAVE-GUIDES; CENTERS; DEFECTS AB Planarization of photosensitive device technology promises to expand the application options for this type of material. In this paper, we report on the production of highly photosensitive thin films, without the use of post-deposition processing, which promise compatibility and integrability with III-V and Si processing. We investigate the optical bleaching of structural defects, responsible for the photosensitive response exhibited by our materials, and assess defect thermal stability. It is seen that films deposited at a substrate temperature of 600 degrees C demonstrate defect stability up to temperatures of approximately 550 degrees C, whereas films deposited on ambient temperature substrates show evidence of structural relaxation at temperatures above 250 degrees C. Such relaxation in the ambient temperature samples is accompanied by changes in the photosensitive response of the material. Finally, we demonstrate the operation of waveguide-based integrated photonic devices within our films. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Simmons-Potter, K (reprint author), Sandia Natl Labs, POB 5800,MS 1423, Albuquerque, NM 87185 USA. NR 15 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 OCT PY 1998 VL 239 IS 1-3 BP 96 EP 103 DI 10.1016/S0022-3093(98)00724-8 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 133YJ UT WOS:000076714900010 ER PT J AU Bloom, EE AF Bloom, EE TI The challenge of developing structural materials for fusion power systems SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID LOW FLUENCE IRRADIATION; BETA-SILICON CARBIDE; CR-MO STEELS; VANADIUM ALLOYS; EMBRITTLEMENT AB Nuclear fusion can be one of the most attractive sources of energy from the viewpoint of safety and minimal environmental impact. Central in the goal of designing a safe, environmentally benign, and economically competitive fusion power system is the requirement for high performance, low activation materials. The general performance requirements for such materials have been defined and it is clear that materials developed for other applications (e.g. aerospace, nuclear fission, fossil energy systems) will not fully meet the needs of fusion. Advanced materials, with composition and microstructure tailored to yield properties that will satisfy the specific requirements of fusion must be developed. The international fusion programs have made significant progress towards this goal. Compositional requirements for low activation lead to a focus of development efforts on silicon carbide composites, vanadium alloys, and advanced martensitic steels as candidate structural material systems. Control of impurities will be critically important in actually achieving low activation but this appears possible. Neutron irradiation produces significant changes in the mechanical and physical properties of each of these material systems raising feasibility questions and design limitations. A focus of the research and development effort is to understand these effects, and through the development of specific compositions and microstructures, produce materials with improved and adequate performance. Other areas of research that are synergistic with the development of radiation resistant materials include fabrication, Joining technology, chemical compatibility with coolants and tritium breeders and specific questions relating to the unique characteristics of a given material (e.g. coatings to reduce gas permeation in SiC composites) or design concept (e.g. electrical insulator coatings for liquid metal concepts). (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Div Met & Ceram, POB 2008,Bldg 4500S, Oak Ridge, TN 37831 USA. EM bloomee@ornl.gov NR 53 TC 105 Z9 108 U1 6 U2 33 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 OCT PY 1998 VL 258 BP 7 EP 17 DI 10.1016/S0022-3115(98)00352-3 PN A PG 11 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000003 ER PT J AU Smith, DL Billone, MC Majumdar, S Mattas, RF Sze, DK AF Smith, DL Billone, MC Majumdar, S Mattas, RF Sze, DK TI Materials integration issues for high performance fusion power systems SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB One of the primary requirements for the development of fusion as an energy source is the qualification of materials for the first-wall/blanket system that will provide high performance and exhibit favourable safety and environmental features. Both economic competitiveness and the environmental attractiveness of fusion will be strongly influenced by the materials constraints. A key aspect is the development of a compatible combination of materials for the various functions of structure, tritium breeding, coolant, neutron multiplication and other special requirements for a specific system. This paper presents an overview of key materials integration issues for high performance fusion power systems. Issues such as: chemical compatibility of structure and coolant, hydrogen/tritium interactions with the plasma facing/ structure/breeder materials, thermomechanical constraints associated with coolant/structure, thermal-hydraulic requirements, and safety/environmental considerations from a systems viewpoint are presented. The major materials interactions for leading blanket concepts are discussed. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Fus Power Program, Technol Dev Div, Argonne, IL 60439 USA. RP Smith, DL (reprint author), Argonne Natl Lab, Fus Power Program, Technol Dev Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM dalesmith@anl.gov NR 28 TC 20 Z9 21 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 OCT PY 1998 VL 258 BP 65 EP 73 DI 10.1016/S0022-3115(98)00355-9 PN A PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000008 ER PT J AU Noda, K Ehrlich, K Jitsukawa, S Moslang, A Zinkle, S AF Noda, K Ehrlich, K Jitsukawa, S Moslang, A Zinkle, S TI Users' requirements for IFMIF SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID FUSION MATERIALS; NEUTRON AB The International Fusion Materials Irradiation Facility (IFMIF) is a high energy neutron irradiation facility which generates an intense neutron flux with D-Li stripping reactions for fusion materials testing. The role of IFMIF is (1) development of various fusion reactor materials, (2) determination of design-relevant engineering databases for the DEMO fusion reactor, (3) calibration and validation of data generated from fission reactor irradiations and the other simulation experiments, etc. The conceptual design activity (CDA) of IFMIF was initiated in February 1995 as an IEA collaborative activity to complete a reference conceptual design of IFMIF in December 1996. Users' requirements for the conceptual design of IFMIF were developed for materials to be tested, types of experiments, small specimen test technology and irradiation conditions. Furthermore, the neutron irradiation field characteristics (spectrum, flux/volume, etc.) of IFMIF were evaluated for the conceptual design parameters and were shown to meet the essential requirements of the users. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. Forschungszentrum Karlsruhe, IMF 1, D-76021 Karlsruhe, Germany. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Noda, K (reprint author), Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. EM noda@ifmif.tokai.jaeri.go.jp OI Zinkle, Steven/0000-0003-2890-6915 NR 27 TC 18 Z9 18 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 OCT PY 1998 VL 258 BP 97 EP 105 DI 10.1016/S0022-3115(98)00429-2 PN A PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000011 ER PT J AU Shannon, TE Jameson, RA Katsuta, H Maekawa, H Martone, M Moslang, A Teplyakov, V Rennich, MJ AF Shannon, TE Jameson, RA Katsuta, H Maekawa, H Martone, M Moslang, A Teplyakov, V Rennich, MJ TI Conceptual design of the international fusion materials irradiation facility (IFMIF) SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID NEUTRON; ESNIT AB The International Fusion Materials Irradiation Facility (IFMIF) conceptual design is complete. The two-year effort was carried out as an activity of the IEA Executive Committee on Fusion Materials. Specialists from Europe, Japan, the United States and the Russian Federation came together in a series of meetings and workshops to define the concepts for the technical systems and the overall design and cost estimate. The goal of the IFMIF is to provide an irradiation facility for use by fusion material scientists in the search for low activation and damage resistant materials, An accelerator-based neutron source has been established through a number of international studies and workshops as an essential step for near-term materials development and testing. IFMIF would also provide calibration and validation of data from fission reactor and other accelerator-based irradiation testing. The design concept consists of a deuteron accelerator producing particle energies in the range of 30-40 MeV. The deuterons interact with a flowing liquid lithium target (D-LI) producing high energy neutrons with a peaked flux around 14 MeV. The resulting high energy neutrons will interact with a test assembly to irradiate test samples of candidate materials up to full lifetime of anticipated use in future fusion energy reactors. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Univ Tennessee, Dept Nucl Engn, Knoxville, TN 37996 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. JAERI, Tokai, Ibaraki, Japan. Euratom ENEA, Frascati, Italy. Euratom FZK Assoc, Karlsruhe, Germany. IHEP, Moscow, Russia. RP Shannon, TE (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. EM tshannon@utk.edu OI Rennich, Mark/0000-0001-6945-0075 NR 22 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 OCT PY 1998 VL 258 BP 106 EP 112 DI 10.1016/S0022-3115(98)00265-7 PN A PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000012 ER PT J AU Muroga, T Ohnuki, S Garner, FA Zinkle, SJ AF Muroga, T Ohnuki, S Garner, FA Zinkle, SJ TI The influence of neutron spectrum and irradiation history on microstructural evolution in fusion structural materials SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID IMPROVED TEMPERATURE CONTROL; FISSION REACTOR IRRADIATION; VANADIUM ALLOYS; COPPER-ALLOYS; ACCUMULATION; DENSITY; METALS; DPA AB The impact of solid transmutant generation and temperature transients during irradiation are new research subjects for application of fission neutron irradiation data to fusion materials development. Fundamental research for these issues is in progress, and includes such approaches as alloying the transmutant elements before irradiation and varying temperature irradiation with charged particles. In addition, novel uses of fission reactors are under way using neutron spectral changes to control solid transmutation, and highly controlled periodically-variable temperature irradiation. The understanding of microstructural processes in such complex and the variable irradiation conditions is growing. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Natl Inst Fus Sci, Gifu 5095292, Japan. Hokkaido Univ, Sapporo, Hokkaido 0608628, Japan. Pacific NW Lab, Richland, WA 99352 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Muroga, T (reprint author), Natl Inst Fus Sci, Gifu 5095292, Japan. EM muroga@nifs.ac.jp OI Zinkle, Steven/0000-0003-2890-6915 NR 53 TC 14 Z9 14 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 OCT PY 1998 VL 258 BP 130 EP 139 DI 10.1016/S0022-3115(98)00266-9 PN A PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000015 ER PT J AU Johnson, CE Noda, K Roux, N AF Johnson, CE Noda, K Roux, N TI Ceramic breeder materials: Status and needs SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID LITHIUM ALUMINATE; TRITIUM RELEASE; OXIDE; ADSORPTION; TECHNOLOGY; KINETICS; LI2O AB The tritium breeding blanket is one of the most important components of a fusion reactor because it directly involves both energy extraction and tritium production, both of which are critical to fusion power. Because of their overall desirable properties, lithium-containing ceramic solids are recognized as attractive tritium breeding materials for fusion reactor blankets. Indeed, their inherent thermal stability and chemical inertness are significant safety advantages. In numerous in-pile experiments, these materials have performed well, showing good thermal stability and good tritium release characteristics. Tritium release is particularly facile when an argon or helium purge gas containing hydrogen, typically at levels of about 0.1%, is used: However, the addition of hydrogen to the purge gas imposes a penalty when it comes to recovery of the tritium produced in the blanket. In particular, a large amount of hydrogen in the purge gas will necessitate a large multiple-stage tritium purification unit, which could translate into higher costs. Optimizing tritium, release while minimizing the amount of hydrogen necessary in the purge gas requires a deeper understanding of the tritium release process, especially the interactions of hydrogen with the surface of the lithium ceramic. This paper reviews the status of ceramic breeder research and highlights several issues and data needs. (C) 1998 Elsevier Science B.V, All rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. CEA, DTA, CEREM, CE2M,LECMA,CE Saclay, F-91191 Gif Sur Yvette, France. RP Johnson, CE (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. EM johnsonce@cmt.anl.gov NR 71 TC 43 Z9 43 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 OCT PY 1998 VL 258 BP 140 EP 148 DI 10.1016/S0022-3115(98)00357-2 PN A PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000016 ER PT J AU Rowcliffe, AF Zinkle, SJ Stubbins, JF Edwards, DJ Alexander, DJ AF Rowcliffe, AF Zinkle, SJ Stubbins, JF Edwards, DJ Alexander, DJ TI Austenitic stainless steels and high strength copper alloys for fusion components SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID MICROSTRUCTURAL EVOLUTION AB An austenitic stainless steel (316LN), an oxide-dispersion-strengthened copper alloy (GlidCop A125), and a precipitation-hardened copper alloy (Cu-Cr-Zr) are the primary structural materials for the ITER first wall/blanket and divertor systems. While there is a long experience of operating 316LN stainless steel in nuclear environments, there is no prior experience with the copper alloys in neutron environments. The ITER first wall (FW) consists of a stainless steel shield with a copper alloy heat sink bonded by hot isostatic pressing (HIP). The introduction of bi-layer structural material represents a new materials engineering challenge; the behavior of the bi-layer is determined by the properties of the individual components and by the nature of the bond interface. The development of the radiation damage microstructure in both classes of materials is summarized and the effects of radiation on deformation and fracture behavior are considered. The initial data on the mechanical testing of bi-layers indicate that the effectiveness of GlidCop A125 as a FW heat sink material is compromised by its strongly anisotropic fracture toughness and poor resistance to crack growth in a direction parallel to the bi-layer interface. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Illinois, Dept Nucl Engn, Urbana, IL 61801 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Rowcliffe, AF (reprint author), Oak Ridge Natl Lab, POB 2008,Bldg 5500, Oak Ridge, TN 37831 USA. EM af8@ornl.gov OI Zinkle, Steven/0000-0003-2890-6915 NR 31 TC 50 Z9 51 U1 1 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 OCT PY 1998 VL 258 BP 183 EP 192 DI 10.1016/S0022-3115(98)00333-X PN A PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000020 ER PT J AU Hishinuma, A Kohyama, A Klueh, RL Gelles, DS Dietz, W Ehrlich, K AF Hishinuma, A Kohyama, A Klueh, RL Gelles, DS Dietz, W Ehrlich, K TI Current status and future R & D for reduced-activation ferritic/martensitic steels SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID FUSION-REACTORS; IRRADIATION AB International research and development programs on reduced-activation ferritic/martensitic steels, the primary candidate-alloys for a DEMO fusion reactor and beyond, are briefly summarized, along with some information on conventional steels. An International Energy Agency (IEA) collaborative test program to determine the feasibility of reduced-activation ferritic/martensitic steels for fusion is in progress and will be completed within this century. Baseline properties including typical irradiation behavior for Fe-(7-9)%Cr reduced-activation ferritic steels are shown. Most of the data are for a heat of modified F82H steel, purchased for the][EA program. Experimental plans to explore possible problems and solutions for fusion devices using ferromagnetic materials are introduced. The preliminary results show that it should be possible to use a ferromagnetic vacuum vessel in tokamak devices. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Tokai Estab, Dept Mat Sci & Engn, Tokai, Ibaraki 31911, Japan. Kyoto Univ, Inst Adv Energy, Uji, Kyoto 611, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Pacific NW Lab, Richland, WA 99352 USA. EC DGXII Fus Program, Brussels, Belgium. Forschungszentrum Karlsruhe, Inst Mat Forsch 1, D-76021 Karlsruhe, Germany. RP Hishinuma, A (reprint author), Japan Atom Energy Res Inst, Tokai Estab, Dept Mat Sci & Engn, Tokai, Ibaraki 31911, Japan. EM ahishi@jmpdsun.tokai.jaeri.go.jp NR 43 TC 148 Z9 157 U1 9 U2 30 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 OCT PY 1998 VL 258 BP 193 EP 204 DI 10.1016/S0022-3115(98)00395-X PN A PG 12 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000021 ER PT J AU Zinkle, SJ Matsui, H Smith, DL Rowcliffe, AF van Osch, E Abe, K Kazakov, VA AF Zinkle, SJ Matsui, H Smith, DL Rowcliffe, AF van Osch, E Abe, K Kazakov, VA TI Research and development on vanadium alloys for fusion applications SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID TI ALLOYS; MICROSTRUCTURE; REACTOR AB The current status of research and development on unirradiated and irradiated V-Cr-Ti alloys intended for fusion reactor structural applications is reviewed, with particular emphasis on the flow and fracture behavior of neutron-irradiated vanadium alloys. Recent progress on fabrication, joining, oxidation behavior, and the development of insulator coatings is also summarized. Pronounced flow localization and loss of strain hardening capacity with uniform elongations <1% generally occurs in vanadium alloys for irradiation temperatures below similar to 400 degrees C (0.31 T-M). These changes in tensile properties for T-irr < 400 degrees C are generally accompanied by large increases in the ductile-to-brittle transition temperature measured under both dynamic and quasi-static loading conditions. The relationships between radiation hardening, flow localization, strain rate, and fracture properties are examined. The irradiated mechanical properties at temperatures between 430 degrees C and 650 degrees C are acceptable for most structural applications. Further work is needed to determine how far the allowable lower and upper operating temperature limits can be expanded beyond the 430-650 degrees C range. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Tohoku Univ, Inst Mat Res, Sendai, Miyagi 98077, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Netherlands Energy Res Fdn, NL-1755 ZG Petten, Netherlands. Tohoku Univ, Dept Quantum Sci & Energy Engn, Sendai, Miyagi 98077, Japan. Res Inst Atom Reactors, Dimitrovgrad, Russia. RP Zinkle, SJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM zinklesj@ornl.gov OI Zinkle, Steven/0000-0003-2890-6915 NR 55 TC 123 Z9 124 U1 2 U2 27 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 OCT PY 1998 VL 258 BP 205 EP 214 DI 10.1016/S0022-3115(98)00269-4 PN A PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000022 ER PT J AU Fenici, P Rebelo, AJF Jones, RH Kohyama, A Snead, LL AF Fenici, P Rebelo, AJF Jones, RH Kohyama, A Snead, LL TI Current status of SiC/SiC composites R & D SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID MATRIX COMPOSITES; MICROSTRUCTURE; TEMPERATURE AB Advantages of SiC-based ceramic matrix composites (CMCs) as structural materials in fusion applications rely on their high-temperature properties and stability, low density and reduced neutron activation. In recent years, experimental activities on industrial SiC CMCs have highlighted their main features under irradiation and provided important guidelines for further development of a radiation compliant material. Parallel efforts included design studies, development of advanced fibres and interfaces, alternative composite processing methods and joint development. In this paper, the current status of SiC/SiC R&D is reported and it is demonstrated that future activities require a strong collaboration with the industry as well as common efforts involving the different laboratories. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Commiss European Communities, Joint Res Ctr, Inst Adv Mat, I-21020 Ispra, VA, Italy. Pacific NW Lab, Richland, WA 99352 USA. Kyoto Univ, Inst Adv Energy, Kyoto 606, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Fenici, P (reprint author), Commiss European Communities, Joint Res Ctr, Inst Adv Mat, Tp 202, I-21020 Ispra, VA, Italy. EM artur.rebelo@jrc.it NR 48 TC 131 Z9 139 U1 2 U2 33 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 OCT PY 1998 VL 258 BP 215 EP 225 DI 10.1016/S0022-3115(98)00303-1 PN A PG 11 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000023 ER PT J AU Castro, RG Elliot, KE Watson, RD Youchison, DL Slattery, KT AF Castro, RG Elliot, KE Watson, RD Youchison, DL Slattery, KT TI Fabrication and high heat flux testing of plasma sprayed beryllium ITER first wall mock-ups SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Plasma-sprayed beryllium ITER first wall mock-ups have survived 3000 thermal fatigue cycles at 1 MM/m(2) without damage during testing at the Plasma Materials Test Facility at Sandia National Laboratory in New Mexico. This heat flux level is twice the expected design heat Bur for ITER first wall modules. Plasma sprayed beryllium mock-ups were vacuum plasma sprayed at the Los Alamos National Laboratory's Beryllium Atomization and Thermal Spray Facility, Results will be reported on the fabrication, high heat flux testing and post-mortem analysis of two beryllium plasma sprayed mock-ups (1) beryllium plasma sprayed directly on a CuNiBe heat sink and (2) beryllium plasma sprayed on a compliant layer of aluminum which was explosion-bonded to a CuCrZr copper heat sink. The high heat flux tests utilized the 30 kW Electron Beam Test System at a Sandia National Laboratory. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Sandia Natl Labs, Fus Technol Dept, Albuquerque, NM 87185 USA. Boeing Co, High Energy Syst, St Louis, MO 63166 USA. RP Castro, RG (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MST-6,Met G770, Los Alamos, NM 87545 USA. EM rcastro@lanl.gov OI Youchison, Dennis/0000-0002-7366-1710 NR 5 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 252 EP 257 DI 10.1016/S0022-3115(98)00078-6 PN A PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000027 ER PT J AU Hassanein, A Wiechers, B Konkashbaev I AF Hassanein, A Wiechers, B Konkashbaev, I TI Tritium behavior in eroded dust and debris of plasma-facing materials SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Tritium behavior in plasma-facing components (PFCs) of future tokamak reactors such as ITER is an essential factor in evaluating and choosing the ideal plasma-facing materials (PFMs). One important parameter that influences tritium buildup and release in candidate materials is the effect of material porosity on tritium diffusion and retention. Diffusion in porous materials, for example, consists of three different processes: along grain boundaries, along microcrystallite boundaries, and in pure crystallite structures. Such diffusion processes have strong nonlinear behavior due to temperature, solubility, and existing trap sites. Therefore, a realistic model for tritium diffusion in porous and neutron-irradiated materials must account for both nonlinear and multidimensional effects. A tritium transport computer model Tritium Accumulation in Porous Structure (TRAPS) has been developed to evaluate and predict the kinetics of tritium transport in porous media. This two-dimensional model incorporates tritium diffusion and trapping processes that also account for hydrogen-isotope solubility limits in PFMs. This model is being coupled with the computer model Tritium In Compound System (TRICS) which has been developed to study the effects of surface erosion to tritium behavior in PFCs. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Forschungszentrum Julich, D-52425 Julich, Germany. Troitsk Inst Innovat & Fus Res, Troitsk, Russia. RP Hassanein, A (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM hassanein@anl.gov NR 7 TC 10 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 295 EP 300 DI 10.1016/S0022-3115(98)00363-8 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000034 ER PT J AU Odegard, BC Cadden, CH Watson, RD Slattery, KT AF Odegard, BC Cadden, CH Watson, RD Slattery, KT TI A review of the US joining technologies for plasma facing components in the ITER fusion reactor SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB This paper is a review of the current joining technologies for plasma facing components in the US for the International Thermonuclear Experimental Reactor (ITER) project. Many facilities are involved in this project. All of those facilities are not represented in the authors list but all contributions will be noted throughout the report and in the acknowledgements. Many unique and innovative joining techniques are being considered in the quest to join two candidate armor plate materials (beryllium and tungsten) to a copper base alloy heat sink (Glidcop, Elbrador). These techniques include brazing and diffusion bonding, compliant layers at the bond interface, and the use of diffusion barrier coatings and diffusion enhancing coatings at the bond interfaces. The development and status of these joining techniques will be detailed in this report. (C) 1998 Published by Elsevier Science B.V All rights reserved. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Boeing Co, St Louis, MO 63166 USA. RP Odegard, BC (reprint author), Sandia Natl Labs, MS 9403,POB 969, Livermore, CA 94551 USA. EM odegard@ca.sandia.gov NR 19 TC 28 Z9 29 U1 2 U2 9 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 OCT PY 1998 VL 258 BP 329 EP 334 DI 10.1016/S0022-3115(98)00402-4 PN A PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000040 ER PT J AU Ingram, FW Palmer, AJ Stites, DJ AF Ingram, FW Palmer, AJ Stites, DJ TI Temperature controlled material irradiation in the advanced test reactor SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The United States Department of Energy (US DOE) has initiated the development of an Irradiation Test Vehicle (ITV) for fusion materials irradiation at the Advanced Test Reactor (ATR) in Idaho Falls, Idaho, USA. The ITV is capable of providing neutron spectral tailoring and individual temperature control for up to 15 experiment capsules simultaneously. The test vehicle consists of three In-Pile Tubes (IPTs) running the length of the reactor vessel. These. IPTs are kept dry and test trains with integral instrumentation are inserted and removed through a transfer shield plate above the reactor vessel head. The test vehicle is designed to irradiate specimens as large as 2.2 cm in diameter, at temperatures of 250-800 degrees C, achieving neutron damage rates as high as 10 displacements per atom per year. The high fast to thermal neutron flux ratio required for fusion materials testing is accomplished by using an aluminum filler to displace as much water as possible from the flux trap and surrounding the filler piece with a ring of replaceable neutron absorbing material. The gas blend temperature control system remains in place fr om test to test, thus hardware costs for new tests are limited to the experiment capsule train and integral instrumentation. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Ingram, FW (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. EM fwi@inel.gov NR 0 TC 1 Z9 1 U1 0 U2 0 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 OCT PY 1998 VL 258 BP 362 EP 366 DI 10.1016/S0022-3115(98)00366-3 PN A PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000046 ER PT J AU Sugimoto, M Jameson, RA Teplyakov, V Berwald, D Blind, B Bruhwiler, D Deitinghoff, H Ferdinand, R Kinsho, M Klein, H Lagniel, JM Miyahara, A Olivier, M Peakock, M Piechowiak, E Pozimski, Y Rathke, J Tanabe, Y Volk, K AF Sugimoto, M Jameson, RA Teplyakov, V Berwald, D Blind, B Bruhwiler, D Deitinghoff, H Ferdinand, R Kinsho, M Klein, H Lagniel, JM Miyahara, A Olivier, M Peakock, M Piechowiak, E Pozimski, Y Rathke, J Tanabe, Y Volk, K TI Accelerator conceptual design of the international fusion materials irradiation facility SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The accelerator system of the International Fusion Materials Irradiation Facility (IFMIF) provides the 250-mA, 40-MeV continuous-wave deuteron beam at one of the two lithium target stations. II consists of two identical linear accelerator modules, each of which independently delivers a 125-mA beam to the common footprint of 20 cm x 5 cm at the target surface. The accelerator module consists of an ion injector, a 175 MHz RFQ and eight DTL tanks, and rf power supply system. The requirements for the accelerator system and the design concept are described. The interface issues and operational considerations to attain the proposed availability are also discussed. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Intense Neutron Source Lab, Tokai, Ibaraki 31911, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Protvino High Energy Phys Inst, Protvino 142284, Moscow Region, Russia. Northrop Grumman Corp, Bethpage, NY 11714 USA. CEA Saclay, LNS, F-91191 Gif Sur Yvette, France. Univ Frankfurt, Inst Angew Phys, D-60054 Frankfurt, Germany. Teikyo Univ, Hachioji, Tokyo 19203, Japan. Northrop Grumman Corp, Baltimore, MD 21203 USA. CEA, DSM, F-91191 Gif Sur Yvette, France. Toshiba Corp, Tsurumi Ku, Yokohama, Kanagawa 230, Japan. RP Sugimoto, M (reprint author), Japan Atom Energy Res Inst, Intense Neutron Source Lab, Tokai, Ibaraki 31911, Japan. EM sugimoto@ifmif.tokai.jaeri.go.jp NR 8 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 367 EP 371 DI 10.1016/S0022-3115(98)00095-6 PN A PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000047 ER PT J AU Katsuta, H Kato, Y Konishi, S Miyauchi, Y Smith, D Hua, T Green, L Benamati, G Cevolani, S Roehrig, H Schutz, W AF Katsuta, H Kato, Y Konishi, S Miyauchi, Y Smith, D Hua, T Green, L Benamati, G Cevolani, S Roehrig, H Schutz, W TI Present status of the conceptual design of IFMIF Target Facility SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The Conceptual Design Activity (CDA) for the International Fusion Materials Irradiation Facility (IFMIF) has been conducted. For the IFMIF Target Facility, the conceptual designs of the following two main components have been performed. The design concept of IFMIF utilizes a high energy deuteron beam of 30-40 MeV and total current of 250 mA, impinging on a flowing lithium jet to produce high energy neutrons for irradiation of candidate fusion materials. (1) The target assembly : The kinetic energy of the deuteron beam is deposited on a Li-jet target and neutrons are produced through the d-Li stripping reaction in this target. The assembly is designed to get a stable lithium jet and to prevent the onset of lithium boiling. For 40-MeV deuteron beam (total current of 250 mA) and a beam footprint of 5 x 20 cm(2) lithium jet dimensions are designed to be 2.5 cm thick and 26 cm wide. The lithium jet parameters are given. (2) Lithium loop: The loop circulates the lithium to and from the target assembly and removes the heat deposited by the deuteron beam containing systems for maintaining the high purity of the lithium required for radiological safety and to minimize corrosion. The maximum lithium flow rate is 130 Vs and the total lithium inventory is about 21 m(3). The IFMIF policy requires that the lithium loop system be designed to guarantee no combustion of lithium in the event of a lithium leak. This can be achieved by use of multiple confinement of the lithium carrying components. The radioactive. waste generated by the Target Facilities is estimated. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. Ishikawajima Harima Heavy Ind Co Ltd, Chiyoda Ku, Tokyo 100, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Westinghouse Sci & Technol Ctr, Pittsburgh, PA 15235 USA. Ente Le Nuove Tecnol Energia & Ambiente, Brasimone, Italy. Ente Le Nuove Tecnol Energia & Ambiente, Bologna, Italy. Forschungszentrum Karlsruhe, D-76021 Karlsruhe, Germany. RP Katsuta, H (reprint author), Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. EM katsuta@ifmif.tokai.jaeri.go.jp NR 7 TC 0 Z9 0 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 OCT PY 1998 VL 258 BP 388 EP 393 DI 10.1016/S0022-3115(98)00096-8 PN A PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000051 ER PT J AU Kato, Y Katsuta, H Konishi, S Ogoshi, M Hua, T Green, L Cevolani, S AF Kato, Y Katsuta, H Konishi, S Ogoshi, M Hua, T Green, L Cevolani, S TI Impurity control in liquid lithium loop for IFMIF target facility SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID DESIGN AB In the IFMIF Lithium target system, the total lithium inventory is about 21 m(3) and the impurities in the lithium are controlled by a cold trap and a hot trap. From the safety standpoint, the control of tritium and beryllium-7 concentration in the lithium is the most important issue. Both elements are to be controlled by a cold trap. As an option for the tritium, a hot trap is also considered. Other impurities such as oxygen, nitrogen and carbon which will affect the compatibility of lithium and loop materials are also controlled by the cold and hot traps to an acceptable level, A swamping method to control the tritium concentration is analyzed. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. Ishikawajima Harima Heavy Ind Co Ltd, Chiyoda Ku, Tokyo 100, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Westinghouse Sci & Technol Ctr, Pittsburgh, PA 15235 USA. Ente Nuove Tecnol Energia & Ambiente, Bologna, Italy. RP Kato, Y (reprint author), Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. EM kato@ifmif.tokai.jaeri.go.jp NR 6 TC 6 Z9 7 U1 1 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 OCT PY 1998 VL 258 BP 394 EP 399 DI 10.1016/S0022-3115(98)00405-X PN A PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000052 ER PT J AU Haines, JR Jitsukawa, I Moslang, A Noda, K Viola, R Zinkle, SJ AF Haines, JR Jitsukawa, I Moslang, A Noda, K Viola, R Zinkle, SJ TI Design concept for the IFMIF test assemblies SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID IRRADIATION TEST FACILITY; FUSION MATERIALS AB According to specific materials testing needs, the available irradiation volume of the International Fusion Materials Irradiation Facility (IFMIF) has been partitioned into a high-flux region that has an irradiation damage rate for Iron of greater than 20 displacements per atom (dpa) per full-power year (fpy), a medium-flux region with 1-20 dpa/fpy, a low-flux region with fluence levels between 0.1 and 1 dpa/fpy, and a very low-flux zone with an annual accumulation of less than 0.1 dpa. A set of test assemblies, which is located immediately downstream from the neutron producing Li-target, vertically supports (1) test modules used for long-term irradiation of specimens in the high- and medium-flux regions, and (2) an array of tubes used for inserting test capsules in the low- and very low-flux regions. Based on this arrangement and on small specimen test technologies, IFMIF is capable of providing sufficient volume and appropriate irradiation environments to meet the requirements defined by the user community. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. Forschungszentrum Karlsruhe, IMF 1, D-76021 Karlsruhe, Germany. CEC, IAM, HFR, NL-1755 ZG Petten, Netherlands. RP Haines, JR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM hainesjr@ornl.gov OI Zinkle, Steven/0000-0003-2890-6915 NR 13 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 400 EP 406 DI 10.1016/S0022-3115(98)00367-5 PN A PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000053 ER PT J AU Qualls, AL Muroga, T AF Qualls, AL Muroga, T TI A varying temperature irradiation experiment for operation in HFIR SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB An experiment to directly compare the effects of neutron fluence received at steady temperature on the microstructure and mechanical properties of candidate fusion reactor structural materials to the effects of receiving 10% of the fluence at reduced temperature has been designed. The Varying Temperature Experiment is being fabricated for irradiation in a large Removable Beryllium (RB) position of the High Flux Isotope Reactor (HFIR). For this experiment, specimen temperatures are elevated and controlled whenever there is substantial neutron fluence to the specimens (reactor power >10%). Half of the specimens are irradiated at two distinct temperatures, and half are irradiated at constant temperature. The capsule features to meet these requirements are described. The experiment will operate for ten reactor cycles beginning in early 1998. This project is a collaborative effort under the Japan-USA cooperative program (Jupiter Project). (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Natl Inst Fus Sci, Gifu 50952, Japan. RP Qualls, AL (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM quallsl@ornl.gov NR 4 TC 9 Z9 9 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 407 EP 412 DI 10.1016/S0022-3115(98)00368-7 PN A PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000054 ER PT J AU Moslang, A Antonnucci, C Daum, E Haines, JR Jitsukawa, I Noda, K Zinkle, S AF Moslang, A Antonnucci, C Daum, E Haines, JR Jitsukawa, I Noda, K Zinkle, S TI Overview of the IFMIF test facility SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB During the past few years, a reference design has been developed for the International Fusion Materials Irradiation Facility (IFMIF). According to the mission and specification of the general requirements, this reference design includes relevant machine parameters and conceptual designs for the major device subsystems - Test Facilities, Lithium Target Facilities and Accelerator Facilities. Major engineering efforts have been undertaken to establish a test cell design that follows closely the users requirements of the fusion materials community and allows safe and completely remote controlled handling. After a short description of the facility requirements, concepts for the two independent test cells, various test assemblies, remote handling equipment and hot cell facilities are presented. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Forschungszentrum Karlsruhe, Inst Mat Forsch 1, D-76021 Karlsruhe, Germany. ENEA, I-40129 Bologna, Italy. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. RP Moslang, A (reprint author), Forschungszentrum Karlsruhe, Inst Mat Forsch 1, POB 3640, D-76021 Karlsruhe, Germany. EM anton.moeslang@imf.fzk.de OI Zinkle, Steven/0000-0003-2890-6915 NR 6 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 OCT PY 1998 VL 258 BP 427 EP 432 DI 10.1016/S0022-3115(98)00234-7 PN A PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000057 ER PT J AU Wong, CPC Whyte, DG Bastasz, RJ Brooks, J West, WP Wampler, WR AF Wong, CPC Whyte, DG Bastasz, RJ Brooks, J West, WP Wampler, WR TI Divertor materials evaluation system (DiMES) SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The mission of the Divertor Materials Evaluation System (DiMES) in DIII-D is to establish an integrated data base from measurements in the divertor of a tokamak in order to address some of the ITER and fusion power reactor plasma material interaction issues. Carbon and metal coatings of Be, W, V, and Mo were exposed to the steady-state outer strike point on DIII-D for 4-18 s. These short exposure times ensure controlled exposure conditions, and the extensive arrays of DIII-D divertor diagnostics provide a well-characterized plasma for modeling efforts. Post-exposure analysis provides a direct measure of surface material erosion rates and the amount of retained deuterium. For carbon, these results match closely with the results of accumulated carbon deposition and erosion, and the corresponding deuterium retention of long term exposure tiles in DIII-D. Deuterium retention of different materials was measured using the He-3(d,p)He-4 nuclear reaction (W.R. Wampler, R. Bastasz, D. Buchenauer et al., J. Nucl. Mater. 233 (1995) 791-797). For carbon, these measurements showed peak deuterium areal density of about 8 x 10(18) D/cm(2) in a co-deposited layer about 6 mu m deep, mainly at the usually detached inboard divertor leg. That layer of carbon near the inner divertor strike point has an atomic saturation concentration of D/C approximate to 0.25, which is not significantly lower than the laboratory-measured saturation retention of 0.4. Under the carbon-contaminated background plasma of DIII-D, metal coatings of Be, V, Mo, and W were exposed to the steady-state outer strike point under ELMing and ELM-free H-mode discharges. The rate of material erosion and deuterium retention were measured. As expected, W shows the lowest erosion rate at 0.1 nm/s and the lowest deuterium uptake of 2 x 10(20) m(2). (C) 1998 Elsevier Science B.V. All rights reserved. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wong, CPC (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. EM clement.wong@gat.com NR 13 TC 36 Z9 36 U1 2 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 OCT PY 1998 VL 258 BP 433 EP 439 DI 10.1016/S0022-3115(98)00407-3 PN A PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000058 ER PT J AU Miwa, Y Jitsukawa, S Hishinuma, A AF Miwa, Y Jitsukawa, S Hishinuma, A TI Development of a miniaturized hour-glass shaped fatigue specimen SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Diametral strain-controlled push-pull fatigue tests with zero mean strain were carried out with miniaturized hourglass shaped specimens of an austenitic stainless steel in solution annealed condition at room temperature. The specimens had a diameter of 1.25 mm at the minimum cross section and a total length of 25.4 mm. The number of cycles to failure (N-f) was equal to or slightly greater than that obtained with standard size specimens. N-f was also revealed to be rather insensitive to the specimen load axis offset, indicating that the requirement of the specimen alignment to the load axis was not very severe for the miniaturized specimen. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Dept Mat Sci & Engn, Tokai, Ibaraki 31911, Japan. RP Miwa, Y (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Bldg 5500,MS 6376, Oak Ridge, TN 37831 USA. EM miway@ornl.gov NR 8 TC 13 Z9 14 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 457 EP 461 DI 10.1016/S0022-3115(98)00306-7 PN A PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000062 ER PT J AU Natesan, K Reed, CB Rink, DL Haglund, RC AF Natesan, K Reed, CB Rink, DL Haglund, RC TI Development and performance of aluminum nitride insulating coatings for application in a lithium environment SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The blanket system is one of the most important components in a fusion reactor because it has a major impact on both the economics and safety of fusion energy. Based on the requirement that an electrically insulating coating on the. inner wall of cooling tubing must minimize the magnetohydrodynamic pressure drop that occurs during the how of liquid metal in a magnetic field, aluminum nitride (AIN) is considered a candidate coating material for the lithium self-cooled blanket concept. Detailed investigations were conducted on the fabrication, metallurgical microstructure, compatibility with liquid Li, and electrical characteristics of AIN as a coating material. Lithium compatibility studies: were conducted in static systems by exposure of AlN-coated specimens for several time periods, at various temperatures, and in various lithium chemistries. Electrical resistance of the specimens was measured at room temperature before and after exposure to liquid Li. The paper discusses the results from ongoing activities on the development of AIN coatings. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Energy Tehcnol Div, Argonne, IL 60439 USA. RP Natesan, K (reprint author), Argonne Natl Lab, Energy Tehcnol Div, Bldg 212,9700 S Cass Ave, Argonne, IL 60439 USA. EM ken_natesan@qmgate.anl.gov RI Elagin, Andrey/I-2359-2012 NR 5 TC 19 Z9 19 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 488 EP 494 DI 10.1016/S0022-3115(98)00370-5 PN A PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000068 ER PT J AU Dalle Donne, M Longhurst, GR Kawamura, H Scaffidi-Argentina, F AF Dalle Donne, M Longhurst, GR Kawamura, H Scaffidi-Argentina, F TI Beryllium R & D for blanket application SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID MECHANICAL-PROPERTIES; IRRADIATED BERYLLIUM; COMPATIBILITY; REACTIVITY AB The paper describes the main problems and the R&D for the beryllium to be used as neutron multiplier in blankets. As the four ITER partners propose to use beryllium in the form of pebbles for their DEMO relevant blankets (only the Russians consider the porous beryllium option as an alternative) and the ITER breeding blanket will use beryllium pebbles as well, the paper is mainly based on beryllium pebbles. Also the work on the chemical reactivity of fully dense and porous beryllium in contact with water steam is described, due to the safety importance of this point. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Forschungszentrum Karlsruhe, INR, D-76021 Karlsruhe, Germany. Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. JAERI, Oarai Res Estab, JMTR, Oarai, Ibaraki 31111, Japan. RP Dalle Donne, M (reprint author), Forschungszentrum Karlsruhe, INR, Postfach 3640, D-76021 Karlsruhe, Germany. EM francesco.scaffidi@inr.fzk.de NR 27 TC 3 Z9 3 U1 0 U2 0 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 OCT PY 1998 VL 258 BP 601 EP 606 PN A PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000088 ER PT J AU Longhurst, GR Anderl, RA Causey, RA Federici, G Haasz, AA Pawelko, RJ AF Longhurst, GR Anderl, RA Causey, RA Federici, G Haasz, AA Pawelko, RJ TI Tritium saturation in plasma-facing materials surfaces SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID BERYLLIUM; DEUTERIUM; HYDROGEN; TUNGSTEN; PERMEATION; TRANSPORT; RETENTION; BEHAVIOR; KINETICS; EROSION AB Plasma-facing components in the International Thermonuclear Experimental Reactor (ITER) will experience, high heat loads and intense plasma fluxes of order 10(20)-10(23) particles/m(2)s. Experiments on Be and W, two of the materials considered for use in ITER, have revealed that a tritium saturation phenomenon can take place under these conditions in which damage to the surface results that enhances the return of implanted tritium to the plasma and inhibits uptake of tritium. This phenomenon is important because it implies that tritium inventories due to implantation in these plasma-facing materials will probably be lower than was previously estimated using classical recombination-limited release at the plasma surface. Similarly, permeation through these components to the coolant streams should be re duced. In this paper we discuss evidences for the existence of this phenomenon, describe techniques for modeling it, and present results of the application of such modeling to prior experiments. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. Sandia Natl Labs, Livermore, CA USA. ITER Garching Joint Work Site, Garching, Germany. Univ Toronto, Inst Aerosp Studies, Toronto, ON, Canada. RP Longhurst, GR (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. NR 35 TC 11 Z9 11 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 OCT PY 1998 VL 258 BP 640 EP 644 DI 10.1016/S0022-3115(98)00112-3 PN A PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000095 ER PT J AU Hassanein, A Konkashbaev, I AF Hassanein, A Konkashbaev, I TI Performance and lifetime assessment of reactor wall and nearby components during plasma instabilities SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID FACING COMPONENTS; DISRUPTION; EROSION; SIMULATION AB Surface and structural damage to plasma-facing components (PFCs) due to the frequent loss of plasma confinement is a serious problem for the tokamak reactor concept. The plasma energy deposited on these components during loss of confinement causes significant surface erosion, possible structural failure, and frequent plasma contamination. Surface damage consists of vaporization, spallation, and liquid splatter of metallic materials. Comprehensive multidimensional models that include thermodynamics and thermal hydraulics of plasma-facing materials (PFMs), eroded-debris/vapor atomic physics and magnetohydrodynamics (MDHs), resulting photon radiation and photon transport, as well as liquid splashing and brittle destruction of materials, are used self-consistently to evaluate and assess our current understanding of the lifetime of PFMs and the various forms of damage they experience. Models are developed to study the stability of the vapor shielding layer, erosion of the melt-layer, brittle destruction/explosive erosion, and the issues involved therein. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Troitsk Inst Innovat & Fus Res, Troitsk, Russia. RP Hassanein, A (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM hassanein@anl.gov NR 22 TC 3 Z9 3 U1 0 U2 0 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 OCT PY 1998 VL 258 BP 645 EP 652 DI 10.1016/S0022-3115(98)00373-0 PN A PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000096 ER PT J AU Vagin, SP Chakrov, PV Utkelbayev, BD Jacobson, LA Field, RD Kung, H AF Vagin, SP Chakrov, PV Utkelbayev, BD Jacobson, LA Field, RD Kung, H TI Microstructural study of hydrogen-implanted beryllium SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Hot pressed beryllium (TGP-56) was implanted by 650 keV H+ ions to a dose of 6.7 x 10(16) cm(-2) at a temperature below 50 degrees C. TEM examinations were performed both at as-irradiated specimens and after post-irradiation annealings at 400-600 degrees C for 15 min. After irradiation, a high density of "black dot" defects with a size of about 5 nm is observed in the straggling zone, some of which are resolved as small dislocation loops. During post-irradiation annealing, growth of dislocation loops and oriented gas-filled bubbles are observed in the damaged zone. The bubbles are strongly elongated along the [0 0 0 1] direction, and their sidelong facts lie along {1-1 0 0} planes. These facets have a regular "toothed" surface with "tooth" facets on {1-1 0 0} planes. The size of the "teeth" increases with annealing temperature, as well as the total volume of bubbles, with their length growing faster than their width. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Inst Atom Energy NNC RK, Almaty Branch, Alma Ata 480082, Kazakhstan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chakrov, PV (reprint author), Inst Atom Energy NNC RK, Almaty Branch, Ibragimova Str 1, Alma Ata 480082, Kazakhstan. EM root@iae.almaty.kz NR 16 TC 4 Z9 4 U1 1 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 OCT PY 1998 VL 258 BP 719 EP 723 DI 10.1016/S0022-3115(98)00377-8 PN A PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000109 ER PT J AU Anderl, RA McCarthy, KA Oates, MA Petti, DA Pawelko, RJ Smolik, GR AF Anderl, RA McCarthy, KA Oates, MA Petti, DA Pawelko, RJ Smolik, GR TI Steam-chemical reactivity for irradiated beryllium SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID TRITIUM; TEMPERATURES; RELEASE AB This paper reports experimental results concerning the influence of neutron irradiation effects and annealing on the chemical reactivity of beryllium exposed to steam. The work entailed: (1) measurements of swelling, porosity and specific surface area for irradiated Be annealed at temperatures ranging from 700 degrees C to 1200 degrees C and (2) measurements of hydrogen generation rates for unirradiated Be, irradiated Be and irradiated-annealed Be exposed to steam at elevated temperatures. For irradiated Be, volumetric swelling increased from 14% at a 700 degrees C anneaI to about 56% at a 1200 degrees C anneal. Gas-release measurements during annealing indicated the development of a surface-collected porosity network. Specific surface areas for irradiated-annealed Be increased with the anneaI temperature. Steam-chemical reactivity was similar for irradiated and unirradiated Be at temperatures between 450 degrees C and 600 degrees C. For irradiated Be exposed to steam at 700 degrees C, the reactivity accelerated rapidly and the specimen experienced a temperature excursion. Irradiated-annealed Be showed enhanced chemical reactivity related to its higher specific surface area. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn Lab, Fus Safety Program, Idaho Falls, ID 83415 USA. RP Anderl, RA (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn Lab, Fus Safety Program, POB 1625, Idaho Falls, ID 83415 USA. EM raa@inel.gov NR 18 TC 27 Z9 27 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 OCT PY 1998 VL 258 BP 750 EP 756 DI 10.1016/S0022-3115(98)00255-4 PN A PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000115 ER PT J AU Bolt, H Scholz, T Boedo, J Finken, KH Hassanein, A AF Bolt, H Scholz, T Boedo, J Finken, KH Hassanein, A TI High heat flux erosion of carbon fibre composite materials in the TEXTOR tokamak SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID ITER AB During plasma disruptions, ELMs, or vertical displacement events (VDEs) high transient heat loads to the plasma facing materials can cause damage such as thermal erosion, cracking, or melting. Self-shielding processes, which take place when a material surface is exposed to a high heat flux from an incident plasma, can lead to a reduction of the deposited energy. Experiments using the fast pneumatic probe of the TEXTOR tokamak were carried out to investigate these effects. The materials tested were carbon fibre reinforced materials with and without Si-addition. The probe with the material specimens was introduced into the edge plasma up to a depth of 9 cm in front of the ALT-II main limiter with a residence time of 80 ms. After the repeated exposure to the TEXTOR-plasma, the material specimens were examined by profilometry and electron microscopy to determine the damage and erosion. It was found that only a very limited zone of the probe tip of about 2.5 mm extension in radial direction showed erosion. The maximum erosion was observed at the very tip of the probe with approx. 30 mu m per exposure. The results of the erosion quantification are compared with the results from numerical simulations and from plasma diagnostic measurements during the exposure of the specimens. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Forschungszentrum Julich, Inst Werkstoffe Energietech, EURATOM Assoc, D-52425 Julich, Germany. Univ Calif San Diego, Fus Energy Program, La Jolla, CA 92093 USA. Argonne Natl Lab, Fus Power Program, Argonne, IL 60439 USA. RP Bolt, H (reprint author), Forschungszentrum Julich, Inst Werkstoffe Energietech, EURATOM Assoc, Postfach 1913, D-52425 Julich, Germany. EM h.bolt@fz-juelich.de 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 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 757 EP 763 DI 10.1016/S0022-3115(98)00308-0 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000116 ER PT J AU Megusar, J Garner, FA AF Megusar, J Garner, FA TI Response of dynamically compacted tungsten to high fluence neutron irradiation at 423-600 degrees C in FFTF SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB When pure tungsten produced by dynamic compaction at 95.3% theoretical density was irradiated in FFTF at temperatures of 423-600 degrees C and neutron doses as high as 14.4 x 10(22) n cm(-2) (E > 0.1 MeV), it densified 2-3% and became very brittle. The brittle behavior resulted in failure at grain surfaces and appears not to be related to neutron-induced transmutation or segregation of transmutants. Based on density change measurements, it can be concluded that significant cavity formation did not occur at these high neutron exposures. reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. MIT, Cambridge, MA 02139 USA. RP Garner, FA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. EM frank.garner@pnl.gov NR 14 TC 1 Z9 1 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 OCT PY 1998 VL 258 BP 940 EP 944 DI 10.1016/S0022-3115(98)00274-8 PN A PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000148 ER PT J AU Edwards, DJ Singh, BN Toft, P Eldrup, M AF Edwards, DJ Singh, BN Toft, P Eldrup, M TI The effect of bonding and bakeout thermal cycles on the properties of copper alloys irradiated at 100 degrees C SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Tensile specimens of GildCop(TM) Al25, CuCrZr and CuNiBe alloys were given various heat treatments corresponding to solution anneal, prime ageing and bonding thermal treatment. Additional specimens were re-aged and given. reactor bakeout treatment at 350 degrees C for 100 h. Specimens were neutron irradiated at 100 degrees C to a dose level of similar to 0.3 dpa in the DR-3 reactor, and post-irradiation tensile tests, electrical resistivity, and microstructural examination were performed. The main effect of the bonding thermal cycle heat treatment was a slight decrease in strength of the CuCrZr and CuNiBe alloys, while strength of the Al25 remained almost unaltered. The post-irradiation tests at 100 degrees C revealed the greatest loss of ductility occurred in the CuCrZr alloy. Irradiation caused a significant reduction in the electrical resistivity of the CuNiBe and a noticeable increase in the case of the CuCrZr, with only a minor change in the Al25 alloy. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Riso Natl Lab, DK-4000 Roskilde, Denmark. RP Edwards, DJ (reprint author), Pacific NW Lab, MS P8-15,POB 999, Richland, WA 99352 USA. EM dan.edwards@pnl.gov NR 10 TC 11 Z9 11 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 OCT PY 1998 VL 258 BP 978 EP 984 DI 10.1016/S0022-3115(98)00388-2 PN A PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000155 ER PT J AU Greenwood, LR Oliver, BM Garner, FA Muroga, T AF Greenwood, LR Oliver, BM Garner, FA Muroga, T TI Calculation and measurement of helium generation and solid transmutants in Cu-Zn-Ni alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID COPPER-ALLOYS; NEUTRON AB A method recently proposed by Garner and Greenwood [1] would allow the separation of the simultaneous and possibly synergistic effects of solid and gaseous transmutation in Cu-Zn-Ni alloys. Copper transmutes primarily to Ni and Zn, leading to an accelerated production of helium from the ingrowth of zinc in mixed-spectrum reactors. Adding Zn to Cu alloys eliminates the time required for this ingrowth and leads to accelerated helium rates which are comparable to the well-known effect in Ni. Using a suitable Cu-Zn-Ni alloy matrix in a comparative irradiation of thermal neutron shielded and unshielded specimens, the separate influences of the solid and gaseous transmutants should be distinguishable. To assess the potential of this proposal, it is necessary to show that we can accurately predict the isotopic and elemental evolution of these alloys. In the current study, several different Cu-Zn-Ni alloys, irradiated in the HFIR JP-23 experiment, were characterized by measuring of the helium content as well as the solid transmutants. The measured values are in good agreement with calculations based on neutron dosimetry, therefore allowing the successful design of the transmutation experiment proposed by Garner and Greenwood. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Natl Inst Fus Sci, Gifu 50952, Japan. RP Greenwood, LR (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. EM lr_greenwood@pnl.gov RI Greenwood, Lawrence/H-9539-2016 OI Greenwood, Lawrence/0000-0001-6563-0650 NR 16 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 985 EP 989 DI 10.1016/S0022-3115(98)00085-3 PN A PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000156 ER PT J AU O'hira, S Steiner, A Nakamura, H Causey, R Nishi, M Willms, S AF O'hira, S Steiner, A Nakamura, H Causey, R Nishi, M Willms, S TI Tritium retention study of tungsten using various hydrogen isotope irradiation sources SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID BERYLLIUM; OPERATION; GRAPHITE AB Tritium retention behavior of wrought tungsten samples was investigated by exposure to various hydrogen isotope irradiation sources under controlled sample characterization and temperature. It is shown that the thermal desorption behavior of deuterium implanted in the bulk was strongly correlated to the change in the microstructure tungsten. Especially, dislocations produced during fabrication play a significant role in increasing hydrogen retention. From thermal desorption experiments using 100 eV deuterium/tritium and 3 keV deuterium ion beams, annealing wrought tungsten at 1773 K reduced tritium retention to about one fifth of that of the unannealed case. However, even without annealing, the ratio of retained atoms/incident ions of hydrogen isotope for wrought tungsten was 5 x 10(-6) at an incident ion fluence of 7 x 10(25) ions/m(2) and a temperature of 523 K, which was lower than the values reported. Results of CVD and single crystal tungsten are also presented. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Tritium Engn Lab, Tokai, Ibaraki 31911, Japan. Sandia Natl Labs, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP O'hira, S (reprint author), Japan Atom Energy Res Inst, Tritium Engn Lab, Tokai, Ibaraki 31911, Japan. EM ohira@tpl.tokai.jaeri.go.jp NR 14 TC 8 Z9 8 U1 0 U2 0 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 OCT PY 1998 VL 258 BP 990 EP 997 DI 10.1016/S0022-3115(98)00315-8 PN A PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000157 ER PT J AU Fabritsiev, SA Pokrovsky, AS Edwards, DJ Zinkle, SJ AF Fabritsiev, SA Pokrovsky, AS Edwards, DJ Zinkle, SJ TI The effect of neutron dose, irradiation and testing temperature on mechanical properties of copper alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The paper presents the results of comparative investigations of radiation embrittlement of UHS-PH copper alloys of Cu-Ni-Be, Cu-Cr-Ni-Si type and the base Cu-Cr-Zr alloy after irradiation to 0.2 dpa at temperatures of 150 degrees C and 300 degrees C. The investigations undertaken and the analysis of changes in the mechanical properties of high-strength alloys of Cu-Ni-Be and Cu-Cr-Ni-Si irradiated to 0.2 dpa at 150 degrees C and 300 degrees C allowed for the conclusion that at low irradiation and testing temperatures alloys are prone to low-temperature embrittlement, which shows up in these alloys in the same way as in ITER base alloy. At elevated irradiation and testing temperatures the high-strength Cu-Ni-Be and Cu-Cr-Ni-Si alloys embrittle, and what is more, demonstrate, when irradiated, a low level of fracture stress (about twice as low as the initial material). (C) 1998 Elsevier Science B.V. All rights reserved. C1 DV Efremov Sci Res Inst Electrophys Apparatus, St Petersburg 189631, Russia. Sci Res Inst Atom Reactors, Dimitrovgrad 433510, Russia. Pacific NW Lab, Richland, WA 99352 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Fabritsiev, SA (reprint author), DV Efremov Sci Res Inst Electrophys Apparatus, St Petersburg 189631, Russia. EM fabr@niiefa.spb.su OI Zinkle, Steven/0000-0003-2890-6915 NR 21 TC 16 Z9 16 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1015 EP 1021 DI 10.1016/S0022-3115(98)00389-4 PN A PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000161 ER PT J AU Tokunaga, K Yoshida, N Kubota, Y Noda, N Motojima, O Youchison, DL Watson, RD Nygren, RE McDonald, JM Marshall, TD AF Tokunaga, K Yoshida, N Kubota, Y Noda, N Motojima, O Youchison, DL Watson, RD Nygren, RE McDonald, JM Marshall, TD TI Material damage and thermal response of LHD divertor mock-ups by high heat flux SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID PLASMA-FACING COMPONENTS; TRANSIENTS; RACLETTE; MODEL AB Mockups for tests were fabricated and thermal response and thermal fatigue lifetime tests using electron beam facilities were carried out to examine material damage and thermal response of carbon carbon fiber composite (CFC) brazed the oxygen free high conductivity (OFHC) for a local island divertor (LID) plate. Model calculation for thermal response was also carried out to explain the phenomena of experimental results. Thermal response tests of an MFC-1 mockup were performed at the condition that the water flow velocity, pressure and temperature were 1.6-10 mis, 1.0-4.0 MPa and 20 degrees C, 150 degrees C respectively. The MFC-1 mockup showed good heat removal performance. In the case of a CX-2002U mockup with 10 mm armor thickness, surface temperature is near 1000 degrees C at 10 MW/m(2). Therefore, use of CX-2002U as armor material is allowable concerning the maximum surface temperature due to heat flux. A thermal fatigue test of the MFC-1 mockup was also performed. Temperatures increase due ro degradation was not observed up to 1000 cycles. Calculation for thermal response was performed using a finite element analysis code. The comparison measured with calculated data presented information of critical heat flux and detachment of the tile. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Kyushu Univ, Appl Mech Res Inst, Kasuga, Fukuoka 816, Japan. Natl Inst Fus Sci, Gifu 50952, Japan. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Tokunaga, K (reprint author), Kyushu Univ, Appl Mech Res Inst, Kasuga, Fukuoka 816, Japan. EM tokunaga@riam.kyushu-u.ac.jp RI Kyushu, RIAM/F-4018-2015; U-ID, Kyushu/C-5291-2016; OI Youchison, Dennis/0000-0002-7366-1710 NR 15 TC 2 Z9 5 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 OCT PY 1998 VL 258 BP 1097 EP 1103 DI 10.1016/S0022-3115(98)00391-2 PN A PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 143VD UT WOS:000077277000176 ER PT J AU Toloczko, MB Garner, FA Eiholzer, CR AF Toloczko, MB Garner, FA Eiholzer, CR TI Irradiation creep of various ferritic alloys irradiated at similar to 400 degrees C in the PFR and FFTF reactors SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Irradiation creep of three ferritic alloys at similar to 400 degrees C has been studied. Specimens were in the form of pressurized tubes. In a joint US/UK creep study, two identical sets of creep specimens constructed from one heat of HT9 were irradiated in fast reactors, one in the Prototypic Fast Reactor (PFR) and the other in the Fast Flux Test Facility (FFTF). The specimens in PFR were irradiated to a dose of similar to 50 dpa, whereas the specimens in FFTF were irradiated to a dose of 165 dpa. The observed swelling and creep behavior were very different in the two reactors. Creep specimens constructed from D57, a developmental alloy ferritic alloy, were also irradiated in PFR to a dose of similar to 50 dpa. Creep behavior typical of previous studies on ferritic alloys was observed. Finally, creep specimens constructed from MA957, a Y2O3 dission-hardened persion-hardened ferritic alloy, were irradiated in FFTF to a dose of similar to 110 dpa. This alloy exhibited a large amount of densification, and the creep behavior was different than observed in more conventional ferritic or ferritic-martensitic alloys. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Washington State Univ, Pullman, WA 99163 USA. Battelle PNNL, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Toloczko, MB (reprint author), Washington State Univ, Pullman, WA 99163 USA. EM mic@wsunix.wsu.edu NR 8 TC 17 Z9 17 U1 2 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 OCT PY 1998 VL 258 BP 1163 EP 1166 DI 10.1016/S0022-3115(98)00165-2 PN B PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500005 ER PT J AU Mukhopadhyay, DK Froes, FH Gelles, DS AF Mukhopadhyay, DK Froes, FH Gelles, DS TI Development of oxide dispersion strengthened ferritic steels for fusion SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB An oxide dispersion strengthened (ODS) ferritic steel with high temperature strength has been developed in line with low activation criteria for application in fusion power systems. The composition Fe-13.5Cr-2W-0.5Ti-0.25Y(2)O(3) was chosen to provide a minimum chromium content to insure fully delta-ferrite stability. High temperature strength has been demonstrated by measuring creep response of the ODS alloy in uniaxial tension at 650 degrees C and 900 degrees C in an inert atmosphere chamber. Results of tests at 900 degrees C demonstrate that this alloy has creep properties similar to other alloys of similar design and can be considered for use in high temperature fusion power system designs. The alloy selection process, materials production, microstructural evaluation and creep testing are described. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Vista Met Inc, McKeesport, PA 15135 USA. Univ Idaho, Inst Mat & Adv Proc, Moscow, ID 83844 USA. RP Gelles, DS (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 14 TC 89 Z9 101 U1 0 U2 27 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 OCT PY 1998 VL 258 BP 1209 EP 1215 DI 10.1016/S0022-3115(98)00188-3 PN B PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500014 ER PT J AU Gelles, DS Hankin, GL Hamilton, ML AF Gelles, DS Hankin, GL Hamilton, ML TI A review of some effects of helium on charpy impact properties of ferritic/martensitic steels SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID IRRADIATION; EMBRITTLEMENT; ISOTOPE AB To evaluate the effect of helium on Charpy impact properties of ferritic/martensitic steels, two approaches are reviewed: quantification of results of earlier tests performed by other researchers on specimens irradiated in reactors with very different neutron spectra, and evaluation of isotopic tailoring experiments. Data analysis can show that if the differences in reactor response are indeed due to helium effects, then irradiation in a fusion machine at 400 degrees C to 100 dpa and 1000 appm He will result in a ductile-to-brittle transition temperature (DBTT) shift of over 500 degrees C. However, it can be shown that the response as a function of dose and helium level is unlikely to be simply due to helium based on physical reasoning. Shear punch tests and microstructural examinations support this conclusion based on irradiated samples of a series of alloys made by adding various isotopes of nickel in order to vary the production of helium during irradiation in High Flux Isotope Reactor (HFIR). The addition of nickel at any isotopic balance to the Fe-12Cr base alloy significantly increased the shear yield and maximum strengths of the alloys. However, helium itself, up to 75 appm at over 7 dpa appears to have little effect on the mechanical properties of the alloys. This behavior is instead understood to result from complex precipitation response. The database for effects of helium on embrittlement based on nickel additions is therefore probably misleading and experiments should be redesigned to avoid nickel precipitation. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Univ Loughborough, IPTME, Loughborough LE11 3UT, Leics, England. RP Gelles, DS (reprint author), Pacific NW Lab, POB 999,MS P8-15, Richland, WA 99352 USA. EM ds_gelles@pnl.gov NR 9 TC 5 Z9 5 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1216 EP 1221 DI 10.1016/S0022-3115(98)00425-5 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500015 ER PT J AU Hamilton, ML Schubert, LE Gelles, DS AF Hamilton, ML Schubert, LE Gelles, DS TI Impact behavior of two low activation steels after irradiation to similar to 67 dpa at 430 degrees C SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Miniature CVN specimens of four martensitic steels, GA3X, F82H, GA4X and HT9, have been impact tested following irradiation at 430 degrees C to 67 dpa. Comparison of the results with those obtained previously at lower doses indicates that the GA3X and F82H alloys, two primary candidate low activation alloys, exhibit similar behavior following irradiation at 430 degrees C to N67 dpa and at 370 degrees C to similar to 15 dpa. Virtually no shift in either ductile to brittle transition temperature (DBTT) or upper shelf energy (USE) was observed in the F82H alloy at 67 dpa for either notched or precracked specimens. This absence of a shift in DBTT and USE in F82H compares with a slight increase in DBTT and a slight decrease in USE for GA3X, and much larger degradation in both properties in GA4X and HT9. The shifts in DBTT and USE observed in both GA4X and HT9 were smaller after irradiation at 430 degrees C to similar to 67 dpa than after irradiation at 370 degrees C to similar to 15 dpa. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. ARINC, Oklahoma City, OK 73135 USA. RP Hamilton, ML (reprint author), Pacific NW Lab, POB 999,MS P8-15, Richland, WA 99352 USA. EM ml_hamilton@pnl.gov NR 8 TC 6 Z9 6 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 OCT PY 1998 VL 258 BP 1222 EP 1227 DI 10.1016/S0022-3115(98)00189-5 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500016 ER PT J AU Klueh, RL Alexander, DJ AF Klueh, RL Alexander, DJ TI Heat treatment effects on impact toughness of 9Cr-1MoVNb and 12Cr-1MoVW steels irradiated to 100 dpa SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Plates of 9Cr-1MoVNb and 12Cr-1MoVW steels were given four different heat treatments: two normalizing treatments were used and for each normalizing treatment two tempers were used. Miniature Charpy specimens from each heat treatment were irradiated to approximate to 20 dpa at 365 degrees C and to approximate to 100 dpa at 420 degrees C in the Fast Flux Test Facility (FFTF). In previous work, the same steels were irradiated in FFTF to 4-5 dpa at 365 degrees C and 35-36 dpa at 420 degrees C. The tests indicated that prior austenite grain size, which was varied by the different normalizing treatments, affected the impact behavior of the 9Cr-1MoVNb but not the 12Cr-1MoVW. Tempering had relatively little effect on the impact behavior of both steels. Conclusions are presented on how heat treatment can be used to optimize impact properties. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Klueh, RL (reprint author), Oak Ridge Natl Lab, POB 2008,MS 6376, Oak Ridge, TN 37831 USA. EM ku2@ornl.gov NR 18 TC 21 Z9 21 U1 1 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 OCT PY 1998 VL 258 BP 1269 EP 1274 DI 10.1016/S0022-3115(98)00319-5 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500024 ER PT J AU Rowcliffe, AF Robertson, JP Klueh, RL Shiba, K Alexander, DJ Grossbeck, ML Jitsukawa, S AF Rowcliffe, AF Robertson, JP Klueh, RL Shiba, K Alexander, DJ Grossbeck, ML Jitsukawa, S TI Fracture toughness and tensile behavior of ferritic-martensitic steels irradiated at low temperatures SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Disk compact tension and sheet tensile specimens of the ferritic-martensitic steels F82H and Sandvik HT-9 were irradiated in the High Flux Isotope Reactor (HFIR) at 90 degrees C and 250 degrees C to neutron doses of 1.5-2.5 dpa. For both steels, radiation hardening was accompanied by a reduction in strain hardening capacity (SHC). When combined with other literature data it is apparent that severe loss of SHC occurs in F82H for irradiation temperatures below similar to 400 degrees C and in HT-9 for irradiation temperatures below similar to 250 degrees C. For both alloys, severe loss of SHC does not correlate with brittle behavior during fracture toughness testing. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Japan Atom Energy Res Inst, Hitachinaka, Ibaraki 312, Japan. RP Oak Ridge Natl Lab, POB 2008,Bldg 5500, Oak Ridge, TN 37831 USA. EM af8@ornl.gov NR 12 TC 45 Z9 48 U1 0 U2 13 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 OCT PY 1998 VL 258 BP 1275 EP 1279 DI 10.1016/S0022-3115(98)00163-9 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500025 ER PT J AU Rohrig, HD DiStefano, JR Chitwood, LD AF Rohrig, HD DiStefano, JR Chitwood, LD TI Effect of hydrogen and oxygen on the tensile properties of V-4Cr-4Ti SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Flat subsized tensile specimens of the vanadium alloy V-4Cr-4Ti were loaded with different amounts of pure hydrogen in order to study its effect on room temperature tensile properties. It was found that, apart from a slight influence of pretreatment, hydrogen can be tolerated up to about 2.5 at.%, whereas higher hydrogen contents lead to catastrophic failure. It is suggested that this behavior is attributed to coexistence of dissolved hydrogen and brittle hydride at room temperature. In addition, some measurements were made with specimens that had been loaded with about 850 wppm oxygen from a low oxygen partial pressure at 500 degrees C (773 K), prior to hydrogen exposure. In this case room temperature ductility, starting from a decreased level, suffered severe deterioration by hydrogen concentrations of much less than 1 at.%. Apparently, in this case, embrittlement is concentrated at the near-surface grain boundaries, and stresses can no longer be absorbed if the matrix gets hardened by the addition of hydrogen. Thus, under the given conditions, oxygen and hydrogen show a strong synergistic effect on the tensile properties of this material. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Forschungszentrum Karlsruhe, Projektleitung Kernfus, D-76021 Karlsruhe, Germany. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Rohrig, HD (reprint author), Forschungszentrum Karlsruhe, Projektleitung Kernfus, Postfach 3640, D-76021 Karlsruhe, Germany. EM roehrig@pkf.fzk.de NR 9 TC 24 Z9 24 U1 2 U2 9 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 OCT PY 1998 VL 258 BP 1356 EP 1360 DI 10.1016/S0022-3115(98)00201-3 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500040 ER PT J AU Grossbeck, ML King, JF Alexander, DJ Rice, PM Goodwin, GM AF Grossbeck, ML King, JF Alexander, DJ Rice, PM Goodwin, GM TI Development of techniques for welding V-Cr-Ti alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID VANADIUM; NIOBIUM AB Welding vanadium alloys is complicated by interstitial impurity introduction and redistribution at elevated temperatures. Gas tungsten are (GTA) welding, which will probably be required for the fabrication of large tokamak structures, must be done in a glove box environment. Welds were evaluated by Charpy testing. GTA welds could be made with a ductile to brittle transition temperature (DBTT) of 50 degrees C with a post-weld heat treatment (PWHT) or by using a heated Ti getter system on the glove box to reduce interstitial contamination. Titanium-O,N,C precipitates in the fusion zone were found to transform to a more oxygen-rich phase during a PWHT of 950 degrees C/2 h. Hydrogen was found to promote cleavage cracking following welding in cases where the atmosphere was contaminated. Grain size and microstructure also affected weld embrittlement. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Grossbeck, ML (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM gro@ornl.gov NR 13 TC 25 Z9 25 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 OCT PY 1998 VL 258 BP 1369 EP 1374 DI 10.1016/S0022-3115(98)00205-0 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500042 ER PT J AU Kurtz, RJ Hamilton, ML Li, H AF Kurtz, RJ Hamilton, ML Li, H TI Grain boundary chemistry and heat treatment effects on the ductile-to-brittle transition behavior of vanadium alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The ductile-to-brittle transition (DBTT) behavior of vanadium alloys currently being developed for fusion power systems is sensitive to thermo-mechanical processing variables and history. Factors which contribute to this sensitivity are (1) pickup of interstitial impurities such as oxygen, nitrogen and carbon during heat treatments and elevated temperature forming operations, (2) the final grain size achieved, (3) removal of impurities from solid solution due to precipitation reactions, and (4) segregation of impurities to grain boundaries. Previous work on a V-5Cr-5Ti (Heat No. 832394) alloy suggested that sulfur segregation or precipitation during final mill annealing may play a role in determining DBTT behavior. The effect of heat treatment on grain boundary chemistry and Charpy impact behavior was investigated using a production-scale heat of V-4Cr-4Ti (Heat No. 832665). Specimens were examined with Auger electron spectroscopy to characterize grain boundary microchemistry for correlation with Charpy impact test results obtained from one-third size specimens. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Kurtz, RJ (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. EM rj.kurtz@pnl.gov NR 8 TC 8 Z9 9 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1375 EP 1379 DI 10.1016/S0022-3115(98)00161-5 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500043 ER PT J AU Gelles, DS Rice, PM Zinkle, SJ Chung, HM AF Gelles, DS Rice, PM Zinkle, SJ Chung, HM TI Microstructural examination of irradiated V-(4-5%,)Cr-(4-5%)Ti SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Microstructural examination results are reported for two heats of V-(4-5%)Cr-(4-5%)Ti irradiated in the EBR-II X530 experiment to 4.5 dpa at similar to 400 degrees C to provide an understanding of the microstructural evolution that may be associated with degradation of mechanical properties. Fine precipitates were observed in high density intermixed with small defect clusters for all conditions examined following the irradiation. The irradiation-induced precipitation does not appear to be affected by preirradiation heat treatment at 950-1125 degrees C. There was no evidence for a significant density of large (diameter > 10 nm) dislocation loops or network dislocations. Analytical investigations successfully demonstrated that the precipitates were enriched in titanium, depleted in vanadium and contained no nitrogen. These results are discussed in terms of future alloy development options. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Pacific NW Lab, MS P8-15,POB 999, Richland, WA 99352 USA. EM ds_gelles@pnl.gov OI Zinkle, Steven/0000-0003-2890-6915 NR 19 TC 26 Z9 26 U1 1 U2 6 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 OCT PY 1998 VL 258 BP 1380 EP 1385 DI 10.1016/S0022-3115(98)00206-2 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500044 ER PT J AU Li, H Kurtz, RJ Jones, RH AF Li, H Kurtz, RJ Jones, RH TI Effect of thickness and loading mode on the fracture properties of V-4Cr-4Ti at room temperature SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID III FRACTURE; TOUGHNESS; STEEL AB The effect of thickness on the room temperature (RT) mode I fracture behavior of V-4Cr-4Ti has been investigated. Mode I fracture properties were measured from J-integral tests of compact tension (CT) specimens ranging in thickness from 6.4 to 25.4 mm. Al specimens were machined in the T-L orientation and vacuum annealed following final machining. Two heats of V-4Cr-4Ti were tested. Specimens 6.4 and 12.7 mm thick were taken from Wah Chang Heat No. 832665. The 25.4 mm thick specimens were obtained from Wah Chang Heat No. 832864. The effect of loading mode on fracture of V-4Cr-4Ti at RT was also studied using material from Heat No. 832665. Mode I fracture behavior was compared to mixed-mode (I/III) fracture properties obtained from modified CT specimens. Crack angles of 0 degrees and 25 degrees were used to vary the ratio of mode III to mode I loading. J-R curves were generated as the basis for determining the affect of loading mode. The specimen loaded in mixed-mode exhibited lower resistance to crack initiation and propagation than pure mode I specimens. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Kurtz, RJ (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. EM rj.kurtz@pnl.gov NR 22 TC 10 Z9 10 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 OCT PY 1998 VL 258 BP 1386 EP 1391 DI 10.1016/S0022-3115(98)00160-3 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500045 ER PT J AU Lansberry, MR Kurtz, RJ Kumar, AS Mueller, GE AF Lansberry, MR Kurtz, RJ Kumar, AS Mueller, GE TI Dynamic finite element analysis of third size charpy specimens of V-4Cr-4Ti SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB A 2-D finite element analysis (FEA) of precracked, one-third-scale CVN specimens of V-4Cr-4Ti was performed to investigate the sensitivity of model results to key material parameters such as yield strength, failure strain and work hardening characteristics. Calculations were carried out at temperatures of -196 degrees C and 50 degrees C. Dynamic FEAs were performed using ABAQUS/Explicit v5.4. Finite element results are compared to experimental Charpy results from the production-scale heat of V-4Cr-4Ti (Heat #832665) as a benchmark. Agreement between the finite element model and the experimental data was very good at -196 degrees C, whereas at 50 degrees C the model predicted an absorbed energy slightly below the experimental value. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Univ Missouri, Rolla, MO 65401 USA. RP Kurtz, RJ (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. EM rj_kurtz@pnl.gov OI Mueller, Gary/0000-0001-5963-9026 NR 7 TC 1 Z9 1 U1 0 U2 0 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 OCT PY 1998 VL 258 BP 1392 EP 1395 DI 10.1016/S0022-3115(98)00207-4 PN B PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500046 ER PT J AU Rice, PM Zinkle, SJ AF Rice, PM Zinkle, SJ TI Temperature dependence of the radiation damage microstructure in V-4Cr-4Ti neutron irradiated to low dose SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Transmission electron microscopy (TEM) was performed on a V-4Cr-4Ti alloy irradiated to damage levels of 0.1-0.5 displacements per atom (dpa) at 110-505 degrees C. A high density of small faulted dislocation loops were observed at irradiation temperatures below 275 degrees C. These dislocation loops became unfaulted at temperatures above similar to 275 degrees C, and a high density of small Ti-rich defect clusters lying on {0 0 1} planes appeared along with the unfaulted loops at temperatures above 300 degrees C. Based on the TEM and tensile measurements, the dislocation barrier strengths of the faulted dislocation loops and {0 0 1} defect clusters are similar to 0.4-0.5 and 0.25, respectively. This indicates that both types of defects can be easily sheared by dislocations during deformation. Cleared dislocation channels were observed following tensile deformation in a specimen irradiated at 268 degrees C. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM zinklesj@ornl.gov OI Zinkle, Steven/0000-0003-2890-6915 NR 31 TC 77 Z9 77 U1 0 U2 9 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 OCT PY 1998 VL 258 BP 1414 EP 1419 DI 10.1016/S0022-3115(98)00208-6 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500051 ER PT J AU Smith, JP Johnson, WR Trester, PW AF Smith, JP Johnson, WR Trester, PW TI Metallurgical bonding development of V-4Cr-4Ti alloy for the DIII-D radiative divertor program SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB General Atomics (GA), in conjunction with the Department of Energy's (DOE) DIII-D Program, is carrying out a plan to utilize a vanadium alloy in the DIII-D tokamak as part of the DIII-D Radiative Divertor (RD) upgrade. The V-4Cr-4Ti alloy has been selected in the U.S. as the leading candidate vanadium alloy for fusion applications. This alloy will be used for the divertor fabrication. Manufacturing development with the V-4Cr-4Ti alloy is a focus of the DIII-D RD Program. The RD structure, part of which will be fabricated from V-4Cr-4Ti alloy, will require many product forms and types of metal/metal bonded joints. Metallurgical bonding methods development on this vanadium alloy is therefore a key area of study by GA. Several solid-state (non-fusion weld) and fusion weld joining methods are being investigated. To date, GA has been successful in producing ductile, high-strength, vacuum leak-tight joints by all of the methods under investigation. The solid-state joining was accomplished in air, i.e., without the need for a vacuum or inert gas environment to prevent interstitial impurity contamination of the V-4Cr-4Ti alloy. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Gen Atom Co, San Diego, CA 92186 USA. RP Johnson, WR (reprint author), Univ Calif Los Alamos Natl Lab, TA-53,Sectro R,Bldg 3,Mail Stop H809, Los Alamos, NM 87545 USA. EM bob.jphnson@gat.com NR 6 TC 5 Z9 5 U1 0 U2 0 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 OCT PY 1998 VL 258 BP 1420 EP 1424 DI 10.1016/S0022-3115(98)00323-7 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500052 ER PT J AU Johnson, WR Smith, JP AF Johnson, WR Smith, JP TI Fabrication of a 1200 kg ingot of V-4Cr-4Ti alloy for the DIII-D radiative divertor program SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Vanadium-chromium-titanium alloys are attractive materials for fusion reactors because of their high-temperature capability and their potential for low neutron activation and rapid activation decay. A V-4Cr-4Ti alloy has been selected in the US as the current leading candidate vanadium alloy for future use in fusion reactor structural applications. General Atomics (GA), in conjunction with the Department of Energy's (DOE) DIII-D Program, is carrying out a plan for the utilization of this vanadium alloy in the DIII-D tokamak. The plan will culminate in the fabrication, installation, and operation of a V-4Cr-4Ti alloy structure in the DIII-D Radiative Divertor (RD) upgrade. The deployment of this vanadium alloy will provide a, meaningful step in the development and technology acceptance of this advanced material for future fusion power devices. Under a GA contract and material specification, an industrial scale 1200 kg heat (ingot) of a V-4Cr-4Ti alloy has been produced and converted into product forms by Wah Chang of Albany, Oregon (WCA). To assure the proper control of minor and trace impurities which affect the mechanical and activation behavior of this vanadium alloy, selected lots of raw vanadium base metal were processed by aluminothermic reduction of high purity vanadium oxide, and were then electron beam melted into two high purity vanadium ingots. The ingots were then consolidated with high purity Cr and Ti, and double vacuum-are melted to obtain a 1200 kg V-4Cr-4Ti alloy ingot. Several billets were extruded from the ingot, and were then fabricated into plate, sheet, and rod at WCA. Tubing was subsequently processed from plate material. The chemistry and fabrication procedures for the product forms were specified on the basis of experience and knowledge gained from DOE Fusion Materials Program studies on previous laboratory-scale heats and a large scale ingot (500 kg) of V-4Cr-4Ti alloy produced by WCA for Argonne National Laboratory (ANL). Charpy V-Notch (CVN) impact tests have been conducted on sheet material from the 1200-kg heat. The values are compared to data obtained on previous heats of the alloy. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Gen Atom Co, San Diego, CA 92186 USA. RP Johnson, WR (reprint author), Univ Calif Los Alamos Natl Lab, TA-53,Sector R,Bldg 3,Mail Stop H809, Los Alamos, NM 87545 USA. EM bob.johnson@gat.com NR 9 TC 35 Z9 37 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 OCT PY 1998 VL 258 BP 1425 EP 1430 DI 10.1016/S0022-3115(98)00209-8 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500053 ER PT J AU Gazda, J Meshii, M Chung, HM AF Gazda, J Meshii, M Chung, HM TI Microstructure of V-4Cr-Ti alloy after low-temperature irradiation by ions and neutrons SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Recent interest in the application of a V-4Cr-4Ti alloy in the ITER prompted an investigation of the effects of low-to-moderate temperature irradiation (<420 degrees C) on the alloy's mechanical properties. Two sets of experiments were conducted. The effects of fast neutron irradiation to approximate to 4 dpa at 390 degrees C were investigated in the X530 experiment in the EBR-II reactor. Irradiation with single (4.5-MeV Ni2+) and dual ion beams (350-keV He+ simultaneously with 4.5-MeV Ni2+) complemented this study. TEM observations showed the formation of a high density of point-defect clusters and dislocation loops (<30 nm diameter) distributed uniformly in both types of specimens. Mechanical property testing of neutron irradiated material showed embrittlement of the alloy. The deformed microstructures were examined by TEM to determine the causes of embrittlement and revealed dislocation channels propagating through the undeformed matrix. The channels are the sole slip paths and they cause early onset of necking and loss of work-hardening. Based on a review of the available literature, suggestions are made for further research of slip localization in V-4Cr-4Ti alloys. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Gazda, J (reprint author), Northwestern Univ, Dept Mat Sci & Engn, 2225 N Campus Dr, Evanston, IL 60208 USA. EM jerzy_gazda@qmgate.anl.gov NR 12 TC 6 Z9 6 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 OCT PY 1998 VL 258 BP 1437 EP 1441 DI 10.1016/S0022-3115(98)00159-7 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500055 ER PT J AU Chung, HM Smith, DL AF Chung, HM Smith, DL TI Tensile and impact properties of vanadium-base alloys irradiated at < 430 degrees C SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Tensile and impact properties were investigated at <430 degrees C on V-Cr-Ti, V-Ti-Si, and V-Ti alloys after irradiation to approximate to 2-46 dpa at 205-430 degrees C in lithium or helium in the fast flux test facility (FFTF), high flux isotope reactor (HFIR), experimental breeder reactor II (EBR-II), and advanced test reactor (ATR). A 500-kg heat of V-4Cr-4Ti exhibited high ductile-brittle transition temperature and minimal uniform elongation as a result of irradiation-induced loss of work-hardening capability. Work-hardening capabilities of 30- and 100-kg heats of V-4Cr-4Ti varied significantly with irradiation conditions, although the 30-kg heat exhibited excellent impact properties after irradiation at approximate to 390-430 degrees C. The origin of the significant variations in the work-hardening capability of V-4Cr-4Ti is not understood, although fabrication variables, annealing history, and contamination from the irradiation environment are believed to play important roles. A 15-kg heat of V-3Ti-1Si exhibited good work-hardening capability and excellent impact properties after irradiation at approximate to 390-430 degrees C. Helium atoms, either charged dynamically or produced via transmutation of boron in the alloys, promote work-hardening capability in V-4Cr-4Ti and V-3Ti-1Si. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Chung, HM (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 Cass Ave,D-212, Argonne, IL 60439 USA. EM hee.chung@anl.gov NR 10 TC 24 Z9 25 U1 1 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 OCT PY 1998 VL 258 BP 1442 EP 1450 DI 10.1016/S0022-3115(98)00325-0 PN B PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500056 ER PT J AU Chung, HM Park, JH Strain, RV Leong, KH Smith, DL AF Chung, HM Park, JH Strain, RV Leong, KH Smith, DL TI Mechanical properties and microstructural characteristics of laser and electron-beam welds in V-4Cr-4Ti SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Mechanical properties and microstructural characteristics of laser and electron-beam (EB) welds of a 500-kg heat of V-4Cr-4Ti were investigated in as-welded condition and after postwelding heat treatment (PWHT) by impact testing, microhardness measurement, optical microscopy, X-ray diffraction, and transmission electron microscopy (TEM). Ductile-brittle-transition temperatures (DBTTs) of the laser and electron-beam welds were significantly higher than that of the base metal. However, excellent impact properties could be restored in both types of welds by postwelding annealing at 1000 degrees C for 1 h in vacuum. Analysis by TEM revealed that annealed weld zones were characterized by extensive networks of fine V(C,O,N) precipitates, which clean away O, C, and N interstitials from the grain matrices. This process is accompanied by simultaneous annealing-out of the dense dislocations present in the weld zone. This finding could be useful in identifying an optimal welding procedure by controlling and adjusting the cooling rate of the weld zone by an innovative method to maximize the precipitation of V(C,O,N). (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Chung, HM (reprint author), Argonne Natl Lab, 9700 Cass Ave,D-212, Argonne, IL 60439 USA. EM hee.chung@anl.gov NR 7 TC 5 Z9 5 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 OCT PY 1998 VL 258 BP 1451 EP 1457 DI 10.1016/S0022-3115(98)00327-4 PN B PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500057 ER PT J AU Kazakov, VA Tsai, HC Chakin, VP Wiffen, FW Rowcliffe, AF Smith, DL Rusanov, AE Teikovtsev, AA Markina, NV Greenwood, LR AF Kazakov, VA Tsai, HC Chakin, VP Wiffen, FW Rowcliffe, AF Smith, DL Rusanov, AE Teikovtsev, AA Markina, NV Greenwood, LR TI Experience in irradiation testing of low-activation structural materials in fast reactor BOR-60 SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB A Russia/US collaborative irradiation experiment on low-activation structural materials, mainly vanadium alloys, was recently completed in the BOR-60 reactor at the Research Institute of Atomic Reactors (RIAR) in Russia. The experiment, designated Fusion-1, was designed to investigate the effects of neutron-induced displacement damage on the microstructure and mechanical properties of these materials at low temperatures, 300-360 degrees C. For purpose of heat transfer and impurity control, the specimens were lithium-bonded to the capsule. After reaching the goal damage dose of 20 displacements per atom (dpa) in approximately 1 year of irradiation, the capsule was discharged and disassembled in a hot cell at RIAR. All specimens were retrieved from the capsule. This paper summarizes the experiment, covering capsule construction, lithium purification and filling, irradiation, disassembly and specimen retrieval, and calculated results of specimen temperatures and damage dose. (C) 1998 Elsevier Science B.V. All rights reserved. C1 SSC RF, Res Inst Atom Reactors, Dimitrovgrad 433510, Ulyanovsk, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. US DOE, Germantown, MD 20874 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. SSC RF IPPE, Obninsk 249020, Kaluga, Russia. Pacific NW Natl Lab, Richland, WA 99352 USA. RP SSC RF, Res Inst Atom Reactors, Dimitrovgrad 433510, Ulyanovsk, Russia. EM fae@omv.niiar.simbirsk.su RI Greenwood, Lawrence/H-9539-2016 OI Greenwood, Lawrence/0000-0001-6563-0650 NR 18 TC 6 Z9 6 U1 0 U2 2 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 OCT PY 1998 VL 258 BP 1458 EP 1465 DI 10.1016/S0022-3115(98)00328-6 PN B PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500058 ER PT J AU Tsai, H Johnson, WR Smith, DL Smith, JP Chung, HM AF Tsai, H Johnson, WR Smith, DL Smith, JP Chung, HM TI Performance of V-4Cr-4Ti material exposed to the DIII-D tokamak environment SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB A series of tests is being conducted in the DIII-D tokamak to determine the effects of environmental exposure on a V-4Cr-4Ti vanadium alloy. These tests are part of the effort to build and install a water-cooled vanadium alloy structure in the DIII-D radiative divertor upgrade. Data from the test series indicate that the performance of the V-4Cr-4Ti alloy would not be significantly affected by environmental exposure. Interstitial absorption by the material appears to be limited to the surface, and neither the tensile nor the impact properties of the material appear to be affected by the exposure. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Gen Atom Co, San Diego, CA 92138 USA. RP Tsai, H (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM htsai@anl.gov 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 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1466 EP 1470 DI 10.1016/S0022-3115(98)00210-4 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500059 ER PT J AU Tsai, H Matsui, H Billone, MC Strain, RV Smith, DL AF Tsai, H Matsui, H Billone, MC Strain, RV Smith, DL TI Irradiation creep of vanadium-base alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB A study of irradiation creep in vanadium-base alloys is underway with experiments in the Advanced Test Reactor (ATR) and the High Flux Isotope Reactor (HFIR) in US. Test specimens are thin-wall sealed tubes with internal pressure loading. The results from the initial ATR irradiation at low temperature (200-300 degrees C) to a neutron damage level of 4.7 dpa show creep rates ranging from approximate to 0 to 1.2 x 10(-5)/dpa/MPa for a 500-kg heat of V-4Cr-4Ti alloy. These rates were generally lower than reported from a previous experiment in BR-10. Because both the attained neutron damage levels and the creep strains were low in the present study, however, these creep rates should be regarded as only preliminary. Substantially more testing is required before a data base on irradiation creep of vanadium alloys can be developed and used with confidence. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Tohoku Univ, Inst Mat Res, Sendai, Miyagi 98077, Japan. RP Tsai, H (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM htsai@anl.gov NR 7 TC 14 Z9 14 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1471 EP 1475 DI 10.1016/S0022-3115(98)00211-6 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500060 ER PT J AU Natesan, K Soppet, WK Uz, M AF Natesan, K Soppet, WK Uz, M TI Effects of oxygen and oxidation on tensile behavior of V-4Cr-4Ti alloy SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Vanadium-base alloys are potential candidates for applications such as the first wall and other structural components of fusion reactors, but a good understanding of the oxidation behavior of the alloys intended for elevated-temperature use is essential. We conducted a systematic study to determine the effects of time and temperature of air exposure on the oxidation behavior and microstructure of V-4Cr-4Ti alloy. Uniaxial tensile tests were conducted at room temperature and at 500 degrees C on preoxidized specimens of the alloy to examine the effects of oxidation time and oxygen migration on maximum engineering stress and uniform and total elongation. The effect of preexposure of the specimens to environments with varying oxygen partial pressures on the tensile properties of the alloy was investigated. Extensive microstructural analyses of the oxygen-exposed/tensile-tested specimens were conducted to evaluate the cracking propensity for the alloy. In addition, tensile-property data for the alloy were correlated with oxygen pressure in the exposure environment, test temperature, and exposure time. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Natesan, K (reprint author), Argonne Natl Lab, Div Energy Technol, Bldg 212,9700 S Cass Ave, Argonne, IL 60439 USA. EM ken_natesan@qmgate.anl.gov NR 3 TC 21 Z9 23 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 OCT PY 1998 VL 258 BP 1476 EP 1481 DI 10.1016/S0022-3115(98)00399-7 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500061 ER PT J AU Kameda, J Bloomer, TE Lyu, DY AF Kameda, J Bloomer, TE Lyu, DY TI Grain boundary segregation of impurities in neutron irradiated and thermally aged vanadium alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID RADIATION-INDUCED SEGREGATION AB A comparison of intergranular impurity segregation induced during neutron irradiation (9.8 x 10(24) n/m(2): E > 0.1 MeV at 438 degrees C for 2120 h) and thermal ageing has been made in V-20 wt% Ti alloys undoped, P-doped and S-doped all containing residual C and O. Intergranular S segregation in an undoped alloy and S desegregation in a S-doped alloy occurred during neutron irradiation. Thermal ageing produced a large increase in the S segregation in the undoped and S-doped alloys. However, unirradiated, thermally aged and irradiated P-doped alloys showed little S segregation. The P-doped alloy had much smaller P segregation than the S segregation in the undoped and S-doped alloys. The grain boundary enrichment of C, O and Ti was reduced during the irradiation but promoted by the thermal ageing. The defect/impurity interaction affecting the impurity solubility and fluxes is considered to control the intergranular impurity segregation during the irradiation. (C) 1998 Elsevier Science B.V, All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Chonju Tech Coll, Dept Die & Mold Design, Chonju 560760, South Korea. RP Iowa State Univ, Ames Lab, Ames, IA 50011 USA. EM kameda@ameslab.gov NR 20 TC 5 Z9 5 U1 0 U2 4 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 OCT PY 1998 VL 258 BP 1482 EP 1486 DI 10.1016/S0022-3115(98)00174-3 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500062 ER PT J AU Iwai, T Sekimura, N Garner, FA AF Iwai, T Sekimura, N Garner, FA TI Effects of helium on void swelling in boron doped V-5Fe alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID NEUTRON-IRRADIATED V; VANADIUM; FFTF; CR AB The effects of helium on void swelling in V-5Fe were investigated with natural boron-doping techniques during FFTF/MOTA (Fast Flux Test Facility/Materials Open Test Assembly) irradiation. Microstructural observation was carried out to understand the swelling behavior obtained from density measurements. The cavity size distribution in V-5Fe-xB (x = 0, 100, and 500 appm) irradiated at temperatures lower than 713 K indicates a suppressant effect of helium on void growth, and an enhancing effect on cavity nucleation. Since the chemical effect of boron addition is competitive with the transmutation effect, the results have been compared with that of the dual ion irradiation experiments to allow separation of the effect of helium from the effect of boron. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Tokyo, Nucl Sci & Technol Res Ctr, Tokai, Ibaraki 31911, Japan. Univ Tokyo, Dept Quantum Engn & Syst Sci, Bunkyo Ku, Tokyo 113, Japan. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Iwai, T (reprint author), Univ Tokyo, Nucl Sci & Technol Res Ctr, 2-22 Shirakata Shirane, Tokai, Ibaraki 31911, Japan. EM iwai@tokai.t.u-tokyo.ac.jp NR 14 TC 2 Z9 2 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1512 EP 1516 DI 10.1016/S0022-3115(98)00175-5 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500068 ER PT J AU Billone, MC Chung, HM Smith, DL AF Billone, MC Chung, HM Smith, DL TI Revision of the tensile database for V-Ti and V-Cr-Ti alloys tested at ANL SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The database for the tensile properties of unirradiated and irradiated V-(0-18) wt%Ti and V-(4-15) wt%Cr-(3-15) wt%Ti alloys tested at Argonne National Laboratory (ANL) has been reviewed and, when necessary, revised. A consistent methodology, based on ASTM terminology and standards, has been used to reanalyze the unpublished load vs. displacement curves for 162 unirradiated samples and 91 irradiated samples to determine revised values for yield strength (YS), ultimate tensile strength (UTS), uniform elongation (UE), and total elongation (TE). The revised values for UE and TE are lower by 5 +/- 2% (strain) and 4 +/- 2% (strain), respectively, than previously reported values, which included displacements due to machine compliance. Revised values for YS and UTS are consistent with previously published values in that they are within the scatter usually associated with these properties. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Energy Technol, Fus Power Program, Argonne, IL 60439 USA. Argonne Natl Lab, Tech Dev Div, Fus Power Program, Argonne, IL 60439 USA. RP Billone, MC (reprint author), Argonne Natl Lab, Div Energy Technol, Fus Power Program, 9700 S Cass Ave, Argonne, IL 60439 USA. EM mike_billone@qmgate.anl.gov NR 13 TC 4 Z9 4 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 OCT PY 1998 VL 258 BP 1523 EP 1527 DI 10.1016/S0022-3115(98)00215-3 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500070 ER PT J AU Youngblood, GE Jones, RH Kohyama, A Snead, LL AF Youngblood, GE Jones, RH Kohyama, A Snead, LL TI Radiation response of SiC-based fibers SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID SILICON-CARBIDE; CERAMIC FIBERS; STABILITY AB Loss of strength in irradiated fiber-reinforced SiC/SiC composite generally is related to degradation in the reinforcing fiber. To assess fiber degradation, the density and length changes were determined for four types of SiC-based fibers (Tyranno, Nicalon CG, Hi Nicalon and Dow X) after high temperature (up to 1000 degrees C) and high dose (up to 80 dpa-SiC) irradiations. For the fibers with nonstoichiometric compositions (the first three types in the list), the fiber densities increased from 6% to 12%. In contrast, a slight decrease in density (<1%) was observed for the Dow X fiber with a quasi-stoichiometric composition. Fiber length changes (0-5.6% shrinkage) suggested small mass losses (1-6%) had occurred for irradiated uncoated fibers. In contrast, excessive linear shrinkage of the pyrocarbon-coated Nicalon CG and Tyranno fibers (7-9% and 16-32%, respectively) indicated that much larger mass losses (11-84%) had occurred for these coated fibers. Crystallization and crystal growth were observed to have taken place at fiber surfaces by SEM and in the bulk by XRD, moreso for irradiated Nicalon CG than for Hi Nicalon fiber. The radiation response of the quasi-stoichiometric Dow X fiber was the most promising. Further testing of this type fiber is recommended. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Kyoto Univ, Inst Adv Energy, Kyoto 611, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Youngblood, GE (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM ge_youngblood@pnl.gov NR 10 TC 32 Z9 36 U1 2 U2 9 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 OCT PY 1998 VL 258 BP 1551 EP 1556 DI 10.1016/S0022-3115(98)00217-7 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500075 ER PT J AU Lewinsohn, CA Jones, RH Youngblood, GE Henager, CH AF Lewinsohn, CA Jones, RH Youngblood, GE Henager, CH TI Fiber creep rate and high-temperature properties of SiC/SiC composites SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID SUBCRITICAL CRACK-GROWTH; SILICON-CARBIDE; STRUCTURAL CHARACTERIZATION; CERAMIC COMPOSITES AB Optimization of the high-temperature structural properties of continuous silicon carbide fiber, silicon carbide matrix composites (SiC/SiC) requires a fundamental understanding of the relationship between fiber, matrix, and interface properties. Results of a study aimed at relating the fiber creep rate to the subcritical crack growth (SCG) rate and fracture properties of SiC/SiC composites have demonstrated that the crack growth rate in a bulk composite is controlled by the fiber creep rate. This result was demonstrated for Nicalon-CG and Hi-Nicalon fiber reinforced material where a 100 degrees C shift in the creep strength of the fiber resulted in a similar shift in the crack growth rate of the composite. Irradiation enhanced creep of SiC fibers and matrix must also be considered in the performance assessment of SiC/SiC composites. An estimate of the impact of irradiation creep of SiC fibers on the SCG of SiC/SiC will be presented. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Lewinsohn, CA (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM ca_lewinsohn@pnl.gov OI Henager, Chuck/0000-0002-8600-6803 NR 24 TC 1 Z9 1 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1557 EP 1561 DI 10.1016/S0022-3115(98)00218-9 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500076 ER PT J AU Toloczko, MB Garner, FA Standring, J Munro, B Adaway, S AF Toloczko, MB Garner, FA Standring, J Munro, B Adaway, S TI Flux and composition dependence of irradiation creep of austenitic alloys irradiated in PFR at similar to 420 degrees C SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID STAINLESS-STEELS AB Swelling and irradiation creep of five austenitic stainless steel alloys irradiated at similar to 420 degrees C in the Prototypic Fast Reactor (PFR) were examined. The specimens were in the form of pressurized creep tubes, constructed in the USA and irradiated in PFR in a joint USA/UK experiment. The alloy compositions varied greatly, with the greatest elemental variation in the nickel content, which ranged from 15% to 40% over the five alloys. For each alloy, at least two identical sets of tubes were constructed. Each tube-set was irradiated at a different neutron flux level. Swelling was observed to vary with both alloy composition and flux. Irradiation creep was examined from the perspective of the (B) over bar = (<(epsilon)over bar>) over dot/<(sigma)over bar> = B-0 + D(S) over dot creep model. The values of both creep coefficients, B-0 and D, were typical for austenitic stainless steels and were found to be insensitive to flux over the range of fluxes in this experiment. However, the creep coefficients may be mildly sensitive to alloy composition. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Washington State Univ, Pullman, WA 99163 USA. UKAEA, Harwell, Berks, England. AEA Technol, Dounreay, Scotland. Battelle Mem Inst, PNNL, Richland, WA 99352 USA. RP Toloczko, MB (reprint author), Battelle Mem Inst, PNNL, MS P8-15,POB 999, Richland, WA 99352 USA. EM mic@wsunix.w-su.edu NR 20 TC 7 Z9 7 U1 0 U2 0 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 OCT PY 1998 VL 258 BP 1606 EP 1612 DI 10.1016/S0022-3115(98)00158-5 PN B PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500085 ER PT J AU Porollo, SI Vorobjev, AN Konobeev, YV Dvoriashin, AM Krigan, VM Budylkin, NI Mironova, EG Garner, FA AF Porollo, SI Vorobjev, AN Konobeev, YV Dvoriashin, AM Krigan, VM Budylkin, NI Mironova, EG Garner, FA TI Swelling and void-induced embrittlement of austenitic stainless steel irradiated to 73-82 dpa at 335-365 degrees C SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Conventional wisdom holds that void swelling of stainless steels falls strongly in swelling rate at temperatures below 400 degrees C and should not reach large swelling levels even at high dpa levels. This perception may be incorrect as demonstrated by an irradiation of the Russian steel EI-847 which, in both the annealed and cold worked conditions, reached swelling levels in the BN-350 fast reactor on the order of greater than or equal to 10% at temperatures of 335-365 degrees C and doses of 73-82 dpa. Consistent with expectations based on earlier studies of other steels at these swelling levels, the steel was found to be exceptionally brittle and to have failed with a rather unusual failure mode. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Bochvars Res Inst Nonorgan Mat, Moscow, Russia. Inst Phys & Power Engn, Obninsk, Kaluga Region, Russia. RP Garner, FA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. EM frank.garner@pnl.gov NR 7 TC 21 Z9 21 U1 4 U2 10 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 OCT PY 1998 VL 258 BP 1613 EP 1617 DI 10.1016/S0022-3115(98)00166-4 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500086 ER PT J AU Vorobjev, AN Budylkin, NI Mironova, EG Porollo, SI Konobeev, YV Garner, FA AF Vorobjev, AN Budylkin, NI Mironova, EG Porollo, SI Konobeev, YV Garner, FA TI Irradiation creep and stress-enhanced swelling of Fe-16Cr-15Ni-Nb austenitic stainless steel in BN-350 SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB A pressurized tube experiment was conducted on a Russian Fe-16Cr-15Ni-Nb stainless steel in the BN-350 reactor in Kazakhstan. Strain data are reported on annealed tubes irradiated to 60 dpa at 480 degrees C and to 20 dpa at 520 degrees C, both at hoop stress levels ranging from 0 to 200 MPa. The strains observed were linear with applied stress, and the void swelling derived from density measurements was clearly enhanced by stress, an observation confirmed by electron microscopy examination. The derived creep coefficients agree well with those found in Western studies on stainless steels. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Bochvars Res Inst Nonorgan Mat, Moscow, Russia. Inst Phys & Power Engn, Obninsk, Russia. RP Garner, FA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 6 TC 8 Z9 10 U1 2 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 OCT PY 1998 VL 258 BP 1618 EP 1622 DI 10.1016/S0022-3115(98)00152-4 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500087 ER PT J AU Hankin, GL Toloczko, MB Hamilton, ML Faulkner, RG AF Hankin, GL Toloczko, MB Hamilton, ML Faulkner, RG TI Validation of the shear punch tensile correlation technique using irradiated materials SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB In previous studies on a variety of unirradiated materials, a linear relationship was developed between uniaxial tensile strength and effective shear strength, as determined from the shear punch test (SPT). Using the same data, a correlation was also developed to predict tensile uniform elongation from shear punch data. Validation of both correlations using a new database on both irradiated and unirradiated materials has been completed successfully. (C) 1998 Published by Elsevier Science B.V. All rights observed. C1 Univ Loughborough, IPTME, Loughborough LE11 3UT, Leics, England. Washington State Univ, Pullman, WA 99164 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Hankin, GL (reprint author), Univ Loughborough, IPTME, Loughborough LE11 3UT, Leics, England. EM g.l.hankin@boro.ac.uk NR 10 TC 43 Z9 45 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1651 EP 1656 DI 10.1016/S0022-3115(98)00203-7 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500093 ER PT J AU Hankin, GL Toloczko, MB Hamilton, ML Garner, FA Faulkner, RG AF Hankin, GL Toloczko, MB Hamilton, ML Garner, FA Faulkner, RG TI Shear punch testing of Ni-59 isotopically-doped model austenitic alloys after irradiation in FFTF at different He/dpa ratios SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID HELIUM DPA RATIO; NI-CR ALLOYS; MECHANICAL-PROPERTIES; VARIABLES AB In this last of a series of papers describing the evolution of microstructure, void swelling and mechanical properties of model austenitic alloys in response to differences in helium/dpa rates, shear punch testing is used to assess the relative effect of helium generation ratios and various important material and environmental variables. Shear punch data confirm the general trends observed in earlier tensile data derived from the Ni-59 isotopic doping experiment. There is a convergence to a common saturation level of yield strength that depends on alloy composition, temperature and displacement rate, but not on starting condition. The approach to saturation can be sensitive to helium/dpa ratio, however, and may depend on the starting state. For reasons not yet known, shear punch tests appear to be more sensitive to such transient differences than are tensile tests. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Loughborough, IPTME, Loughborough LE11 3UT, Leics, England. Washington State Univ, Pullman, WA 99164 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Hankin, GL (reprint author), Univ Loughborough, IPTME, Loughborough LE11 3UT, Leics, England. EM g.l.hankin@lboro.ac.uk NR 16 TC 24 Z9 25 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 OCT PY 1998 VL 258 BP 1657 EP 1663 DI 10.1016/S0022-3115(98)00204-9 PN B PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500094 ER PT J AU Ioka, I Naito, A Shiba, K Robertson, JP Jitsukawa, S Hishinuma, A AF Ioka, I Naito, A Shiba, K Robertson, JP Jitsukawa, S Hishinuma, A TI Effects of annealing on the tensile properties of irradiated austenitic stainless steel SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID EVOLUTION; ALLOYS AB The austenitic stainless steel (Fe-0.06C-0.55Si-1.8Mn-14Cr-16Ni-2Mo-0.24Ti) was irradiated in a triple ion facility and the High Flux Isotope Reactor. The materials used were in the solution annealed (SA) and 15% cold-worked (CW) condition. TEM and tensile specimens were irradiated to a dose level of 30 and 10 dpa at 200 degrees C. Some of the specimens were annealed after the irradiation at 500 degrees C for 8 h in a vacuum. Microhardness tests were carried out on the surface of the TEM disks at room temperature. Tensile tests were carried out at 200 degrees C in a vacuum with strain rate of about 1 x 10(-3) s(-1). The microhardness of both SA and CW increased by ion irradiation and then decreased by annealing. The yield strengths of the neutron irradiated SA and CW decreased to 610 and 650 MPa by annealing, respectively. The strain to necking of the irradiated CW recovered from 0.7% to 7.6%. The fracture mode remained ductile in each case, (C) 1998 Elsevier Science B.V. All rights reserved. C1 Japan Atom Energy Res Inst, Dept Nucl Energy Syst, Tokai, Ibaraki 3191195, Japan. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Ioka, I (reprint author), Japan Atom Energy Res Inst, Dept Nucl Energy Syst, 2-4 Shirakata, Tokai, Ibaraki 3191195, Japan. EM ioka@popsvr.tokai.jaeri.go.jp NR 19 TC 1 Z9 1 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1664 EP 1668 DI 10.1016/S0022-3115(98)00225-6 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500095 ER PT J AU Sagaradze, VV Lapin, SS Goshchitskii, BN Kirk, MA AF Sagaradze, VV Lapin, SS Goshchitskii, BN Kirk, MA TI The structural evolution of new low-activation and chromium-nickel stainless steels under high-dose irradiation up to 200 dpa SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID ALLOYS AB This paper deals with the evolution of the dislocation structure, phase composition and vacancy voids in new reactor stainless steels over the temperature interval from 500 degrees C to 700 degrees C under irradiation with electrons, neutrons and krypton ions up to high damaging doses (200 dpa). It is shown that the amount of voids formed in stainless steels exposed to irradiation with high-energy particles can be reduced by producing a high-density of direct and indirect sinks of point defects in the form of alpha/gamma phase boundaries and dispersed intermetallics (gamma' and alpha' phases in FCC and BCC steels, respectively) formed under irradiation. Compositions of radiation-resistant alloys, including low-activation ones of the Cr13Mn7W2 type having an austenitic/martensitic lath structure, have been proposed. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, Inst Met Phys, Ural Branch, Sverdlovsk 620219, Russia. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Sagaradze, VV (reprint author), Russian Acad Sci, Inst Met Phys, Ural Branch, 18 S Kovalevskaya Str, Sverdlovsk 620219, Russia. EM rdnr@neutron.e-burg.su RI Sagaradze, Victor/J-5570-2013 OI Sagaradze, Victor/0000-0002-6426-3382 NR 11 TC 1 Z9 1 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1675 EP 1680 DI 10.1016/S0022-3115(98)00401-2 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500097 ER PT J AU Garner, FA Toloczko, MB Grossbeck, ML AF Garner, FA Toloczko, MB Grossbeck, ML TI The dependence of irradiation creep in austenitic alloys on displacement rate and helium to dpa ratio SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Before the parametric dependencies of irradiation creep can be confidently determined, analysis of creep data requires that the various creep and non-creep strains be separated, as well as separating the transient, steady-state, and swelling-driven components of creep. When such separation is attained, it appears that the steady-state creep compliance, B-0, is not a function of displacement rate, as has been previously assumed. Tt also appears that the formation and growth of helium bubbles under high helium generation conditions can lead to a significant enhancement of the irradiation creep coefficient. This is a transient influence that disappears as void swelling begins to dominate the total strain, bur this transient can increase the apparent creep compliance by 100-200% at relatively low (less than or equal to 20) dpa levels. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Garner, FA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. EM frank.garner@pnl.gov NR 11 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1718 EP 1724 DI 10.1016/S0022-3115(98)00227-X PN B PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500104 ER PT J AU Garner, FA Oliver, BM Greenwood, LR AF Garner, FA Oliver, BM Greenwood, LR TI The dependence of helium generation rate on nickel content of Fe-Cr-Ni alloys irradiated to high dpa levels in EBR-II SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Fusion-relevant helium-effects experiments conducted on austenitic steels in the Materials Open Test Assembly (MOTA) of the Fast Flux Test Facility (FFTF) fast reactor had to recognize the contributions of both the high neutron energy (n,alpha) reactions and that of the Ni-58(n,gamma) Ni-59(n,alpha) reaction sequence with low energy neutrons. An experiment conducted in the harder neutron spectra found within the core of Experimental Breeder Reactor-II (EBR-II) has shown that the helium in this reactor was generated almost exclusively from the interaction of high energy neutrons with the natural isotopes of nickel. There was very little contribution from Ni-59. The helium production was found to scale directly with the nickel content over the range 25-75% Ni. Even at very high neutron exposures, the helium production in such reactors can be predicted within 5% accuracy on the basis of high energy reactions as demonstrated by an experiment conducted on three Fe-15Cr-Ni ternary alloys irradiated to doses of 75-131 dpa in EBR-II. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Garner, FA (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM frank.garner@pnl.gov RI Greenwood, Lawrence/H-9539-2016 OI Greenwood, Lawrence/0000-0001-6563-0650 NR 9 TC 8 Z9 8 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 OCT PY 1998 VL 258 BP 1740 EP 1744 DI 10.1016/S0022-3115(98)00297-9 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500108 ER PT J AU Grossbeck, ML Klueh, RL Cheng, ET Peterson, JR Woolery, MR Bloom, EE AF Grossbeck, ML Klueh, RL Cheng, ET Peterson, JR Woolery, MR Bloom, EE TI Analysis of V-Cr-Ti alloys in terms of activation of impurities SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Vanadium alloys offer many advantages including reduced neutron activation. However, activation of V-Cr-Ti alloys is controlled by impurities. This study analyzes four impurity levels for the alloy V-4Cr-4Ti. The first Is an existing commercial heat of the alloy and the others are based on impurity levels attainable by three processes. One process uses a dedicated production plant: another uses a chemical recrystallization process, and the remaining one uses state-of-the-art laboratory purification. It was assumed that the alloys were irradiated as first wall and blanket structures in a fusion reactor operating for four full power years at a wall loading of 5 MW y/m(2). It was found that the two purest alloys and, with special selection, the three purest alloys will meet the criteria for shallow land burial after a cooling time of 50 years. However, none of the alloys were found to meet the criteria for hands-on reprocessing after a cooling time of 100 years. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. TSI Res Inc, Solana Beach, CA 92075 USA. Wah Chang, Albany, OR 97321 USA. Stratcor, Hot Springs, AR 71901 USA. RP Grossbeck, ML (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM gro@ornl.gov NR 7 TC 9 Z9 9 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 OCT PY 1998 VL 258 BP 1778 EP 1783 DI 10.1016/S0022-3115(98)00228-1 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500115 ER PT J AU Shiiyama, K Howlader, MMR Zinkle, SJ Shikama, T Kutsuwada, M Matsumura, S Kinoshita, C AF Shiiyama, K Howlader, MMR Zinkle, SJ Shikama, T Kutsuwada, M Matsumura, S Kinoshita, C TI Electrical conductivity and current-voltage characteristics of alumina with or without neutron and electron irradiation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID RADIATION-INDUCED CONDUCTIVITY; IN-SITU MEASUREMENT; DEGRADATION; AL2O3; INSULATORS; BREAKDOWN; CERAMICS; REACTOR AB The in situ measurement of electrical conductivity and of current-voltage (I-V) characteristics of single- and polycrystal alumina have been carried out both in HFIR (high flux isotope reactor; Oak Ridge National Laboratory) at 723 K with or without neutron irradiation and in a High Voltage Electron Microscope (HVEM) from room temperature to 723 K with or without 1 MeV electron irradiation. Radiation induced conductivity (RIC) was observed for all specimens under neutron and electron irradiation. The RIC under electron irradiation increased with increasing electron flux. There was no catastrophic bulk or surface conductivity degradation under neutron and electron irradiation up to >2 dpa and 9.1 x 10(-5) dpa, respectively. Non-ohmic I-V behavior was observed for all specimens with or without neutron and electron irradiation. The I-V behavior with irradiation was similar to that without irradiation. The reason for non-ohmic behavior is discussed on the basis of the difference of work function between electrode and specimen materials. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Kyushu Univ, Dept Nucl Engn, Higashi Ku, Fukuoka 8128581, Japan. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Tohoku Univ, Inst Mat Res, Oarai Branch, Oarai, Ibaraki 3111313, Japan. RP Shiiyama, K (reprint author), Kyushu Univ, Dept Nucl Engn, Higashi Ku, Fukuoka 8128581, Japan. EM kstne@mbox.nc.kyushu-u.ac.jp RI Shikama, Tatsuo/C-3042-2011; Howlader, Matiar/D-4961-2015; OI Howlader, Matiar/0000-0001-8423-0791; Zinkle, Steven/0000-0003-2890-6915 NR 23 TC 12 Z9 12 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1848 EP 1855 DI 10.1016/S0022-3115(98)00339-0 PN B PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500128 ER PT J AU Shikama, T Zinkle, SJ AF Shikama, T Zinkle, SJ TI Long term degradation of electrical insulation of Al2O3 under high flux fission reactor irradiation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID RADIATION AB Long term increase of electrical conductivity under irradiation was observed in some Al2O3 (polycrystal and single crystal alumina) specimens in in situ electrical measurements in the High Flux Isotope Reactor in the framework of the Japan/USA collaboration called JUPITER project. Especially, chromium doped single crystal alumina showed substantial increase of electrical conductivity at moderate doses of similar to 0.1 dpa, which had similarity to the phenomenon called radiation induced electrical degradation (RIED). Irradiation to doses above 0.1 dpa did not cause a further degradation of electrical conductivity, but instead resulted in an improvement in insulating ability. Behavior of the observed increase of electrical conductivity is described in conjunction with the reported phenomena in RIED and some mechanisms responsible for the observed increase are speculated from the results obtained. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Tohoku Univ, Inst Mat Res, Oarai Branch, Oarai, Ibaraki 3111313, Japan. RP Zinkle, SJ (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. EM zinklesj@ornl.gov RI Shikama, Tatsuo/C-3042-2011; OI Zinkle, Steven/0000-0003-2890-6915 NR 12 TC 21 Z9 21 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 OCT PY 1998 VL 258 BP 1861 EP 1866 DI 10.1016/S0022-3115(98)00299-2 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500130 ER PT J AU Shikama, T Zinkle, SJ Shiiyama, K Snead, LL Farnum, EH AF Shikama, T Zinkle, SJ Shiiyama, K Snead, LL Farnum, EH TI Electrical properties of ceramics during reactor irradiation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID DEGRADATION; INSULATORS AB Twelve different types of polycrystal and single crystal Al2O3 (alumina and sapphire) specimens of varying grades of purity were irradiated for three reactor cycles in a removable beryllium position in a High Flux Isotopes Reactor (HFIR) at Oak Ridge National Laboratory at a temperature of 720-760 K up to a maximum dose of 3 dpa while a de electric field of 200 V/mm was applied. The recently completed Temperature Regulated In Situ Test (TRIST) facility in the HFIR was used to perform in situ measurements of electrical conductivity. In addition, three Al2O3 specimens were simultaneously irradiated without a continuously applied de electric field. In situ electrical conductivity measurements were performed on the specimens before, during and following each irradiation cycle. Behavior of electrical conduction in Al2O3 was studied, with special emphasis on detection of any long-term increase of the electrical conductivity. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Tohoku Univ, Inst Mat Res, Oarai Branch, Oarai, Ibaraki 31113, Japan. Kyushu Univ 36, Dept Nucl Engn, Fukuoka 812, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Zinkle, SJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM zinklesj@ornl.gov RI Shikama, Tatsuo/C-3042-2011; OI Zinkle, Steven/0000-0003-2890-6915 NR 14 TC 20 Z9 20 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1867 EP 1872 DI 10.1016/S0022-3115(98)00300-6 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500131 ER PT J AU Ibarra, A Bravo, D Garcia, MA Llopis, J Lopez, FJ Garner, FA AF Ibarra, A Bravo, D Garcia, MA Llopis, J Lopez, FJ Garner, FA TI Dose dependence of neutron irradiation effects on MgAl2O4 spinels SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID RADIATION-RESISTANCE; CRYSTALS; CERAMICS; DAMAGE AB The characteristics of the photoluminescence and electron paramagnetic resonance CESR) spectra of stoichiometric MgAl2O4 spinel specimens irradiated in FFTF-MOTA at temperatures between 385 degrees C and 750 degrees C to fluences ranging from 5.3 to 24.9 x 10(26) nm(-2) are measured. Photoluminescence spectra show a complex behaviour associated with the presence of an active defect with different surroundings. The EPR spectra show two different bands that are associated with different defects. (C) 1998 Elsevier Science B.V. All rights reserved. C1 CIEMAT, Inst Invest Basica, Euroatom CIEMAT Assoc, E-28040 Madrid, Spain. Univ Autonoma Madrid, Fac Ciencias C4, Dept Fis Mat, E-28049 Madrid, Spain. Univ Complutense Madrid, Fac Ciencias Fis, Dept Fis Mat, E-28040 Madrid, Spain. Pacific NW Lab, Richland, WA USA. RP Ibarra, A (reprint author), CIEMAT, Inst Invest Basica, Euroatom CIEMAT Assoc, Avda Complutense 22, E-28040 Madrid, Spain. EM ibarra@ciemat.es RI Garcia, Miguel Angel/N-3043-2016; OI Garcia, Miguel Angel/0000-0001-9972-2182; Ibarra, Angel/0000-0002-2420-2497 NR 15 TC 6 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1902 EP 1907 DI 10.1016/S0022-3115(98)00130-5 PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500138 ER PT J AU Voitsenya, VS Bardamid, AF Gritsyna, VT Konovalov, VG Motojima, O Orlinskij, DV Palladino, R Peterson, BJ Shapoval, AN Shtan, AF Solodovchenko, SI Yakimov, KI Young, K AF Voitsenya, VS Bardamid, AF Gritsyna, VT Konovalov, VG Motojima, O Orlinskij, DV Palladino, R Peterson, BJ Shapoval, AN Shtan, AF Solodovchenko, SI Yakimov, KI Young, K TI On the choice of materials for the first mirrors of plasma diagnostics in a fusion reactor SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The reflectivity coefficient, R, of mirrors fabricated from different metals (Al, Cu, Mo, Ta, W) in the wavelength range 0.25-0.65 mu m was investigated under long-term sputtering with ions of ECR plasma of hydrogen or deuterium, and R values versus thickness of sputtered layer were measured. For copper mirrors the influence of ion energy and ion energy spectrum on optical reflectivity was investigated in detail. Because a strong effect was found, the comparative test of mirrors made of different metals was carried out using ions with a wide energy distribution (0.1-1.5 keV) to have a more adequate simulation of fusion reactor environment conditions. The results obtained show that, with the exception of Al, the decrease of reflectivity coefficient with thickness of sputtered layer has approximately similar rate for metal tested. Thus, mirrors made of materials having lower sputtering coefficient, Y, will withstand a higher charge exchange atom fluence, in qualitative agreement with R/Y criterion suggested by the authors earlier. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. Taras Shevchenko Univ, UA-252017 Kiev, Ukraine. Kharkov State Univ, UA-310077 Kharkov, Ukraine. Natl Inst Fus Sci, Toki 5095292, Japan. IV Kurchatov Atom Energy Inst, Moscow 123182, Russia. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Voitsenya, VS (reprint author), Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. NR 15 TC 10 Z9 12 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD OCT PY 1998 VL 258 BP 1919 EP 1923 DI 10.1016/S0022-3115(98)00129-9 PN B PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500141 ER PT J AU Smolik, GR McCarthy, KA Petti, DA Coates, K AF Smolik, GR McCarthy, KA Petti, DA Coates, K TI Hydrogen generation from steam reaction with tungsten SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB A LOCA in a fusion reactor involving an ingress of steam presents a safety concern due to hydrogen generated from steam reactions with plasma facing components. Hydrogen concentrations must be maintained below explosive levels. To support safety evaluations we have experimentally determined hydrogen generation rates when a tungsten alloy is exposed to steam from 400 degrees C to 1200 degrees C. We studied effects of steam pressure between 2.8 x 10(4) and 8.5 x 10(4) Pa, i.e., (0.28-0.84 atm) and gas velocity between 0.011 and 0.063 m/s. We present relationships for the reaction rates, oxidation phases, and mechanisms associated with the hydrogen generation. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, LMITCO, Idaho Falls, ID 83415 USA. RP Smolik, GR (reprint author), Idaho Natl Engn & Environm Lab, LMITCO, POB 1625, Idaho Falls, ID 83415 USA. EM grs1@inel.gov NR 7 TC 10 Z9 10 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 OCT PY 1998 VL 258 BP 1979 EP 1984 DI 10.1016/S0022-3115(98)00169-X PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500151 ER PT J AU Fabritsiev, SA Pokrovsky, AS Edwards, DJ Zinkle, SJ Rowcliffe, AF AF Fabritsiev, SA Pokrovsky, AS Edwards, DJ Zinkle, SJ Rowcliffe, AF TI The effect of neutron irradiation on mechanical properties of Cu/SS joints for ITER applications SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The paper presents the first results on the properties of Cu//SS-type joints irradiated in the SM-2 reactor up to a dose of 0.2 dpa at T-irr = 150 degrees C and 300 degrees C. The investigations performed demonstrated that the proposed HIP (RF) and (US) technology, as well as Explosive Bonding (US) holds promises and can be recommended for preparation of samples for subsequent irradiation. On the other hand, the investigation undertaken revealed the problem of 150 degrees C embrittlement of joints observed for Lap Shear specimens GlidCop A125//316LN (US) manufactured by the HIP method. (C) 1998 Elsevier Science B.V. All rights reserved. C1 DV Efremov Sci Res Inst, St Petersburg 189631, Russia. Sci Res Inst Atom Reactors, Dimitrovgrad 433510, Russia. Pacific NW Lab, Richland, WA 99352 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Fabritsiev, SA (reprint author), DV Efremov Sci Res Inst, St Petersburg 189631, Russia. EM fabr@niiefa.spb.su OI Zinkle, Steven/0000-0003-2890-6915 NR 11 TC 14 Z9 14 U1 0 U2 0 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 OCT PY 1998 VL 258 BP 2069 EP 2074 DI 10.1016/S0022-3115(98)00422-X PN B PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500167 ER PT J AU Abe, K Kohyama, A Namba, C Wiffen, FW Jones, RH AF Abe, K Kohyama, A Namba, C Wiffen, FW Jones, RH TI Neutron irradiation experiments for fusion reactor materials through JUPITER program SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID FISSION REACTOR AB A Japan-USA Program of irradiation experiments for fusion research, "JUPITER", has been established as a 6 year program from 1995 to 2000. The goal is to study "the dynamic behavior of fusion reactor materials and their response to variable and complex irradiation environment". This is phase-three of the collaborative program, which follows RTNS-II Program (Phase-1: 1982-1986) and FFTF/MOTA Program (Phase-2: 1987-1994). This program is to provide a scientific basis for application of materials performance data, generated by fission reactor experiments, to anticipated fusion environments. Following the systematic study on cumulative irradiation effects, done through FFTF/MOTA Program, JUPITER is emphasizing the importance of dynamic irradiation effects on materials performance in fusion systems. The irradiation experiments in this program include low activation structural materials, functional ceramics and other innovative materials. The experimental data are analyzed by theoretical modeling and computer simulation to integrate the above effects. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Tohoku Univ, Dept Quantum Sci & Energy Engn, Aoba Ku, Sendai, Miyagi 9808579, Japan. Kyoto Univ, Inst Adv Energy, Uji 6110011, Japan. Natl Inst Fus Sci, Toki 5095292, Japan. US Dept Energy, Germantown, MD 20874 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Abe, K (reprint author), Tohoku Univ, Dept Quantum Sci & Energy Engn, Aoba Ku, Sendai, Miyagi 9808579, Japan. EM katsunori.abe@qse.tohoku.ac.jp NR 13 TC 12 Z9 12 U1 2 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 OCT PY 1998 VL 258 BP 2075 EP 2078 DI 10.1016/S0022-3115(98)00424-3 PN B PG 4 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142MD UT WOS:000077203500168 ER PT J AU Caveliers, V Franken, PR Lin, Q Mokler, FT Luo, HM Knapp, FF AF Caveliers, V Franken, PR Lin, Q Mokler, FT Luo, HM Knapp, FF TI Intra-individual comparison of 3(R)-BMIPP and 3(S)-BMIPP isomers in humans SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid; fatty acids; biodistribution study ID SUBACUTE MYOCARDIAL-INFARCTION; IODINE-123-LABELED FATTY-ACIDS; EMISSION TOMOGRAPHY; PENTADECANOIC ACID; WALL-MOTION; I-123; BMIPP; IODINE-123-BMIPP; DISEASE; ANALOG AB The racemic 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid (BMIPP) is currently used at several centers for myocardial metabolic imaging with SPECT, Recently, the 3(R)-BMIPP isomer showed a 20%-25% higher myocardial uptake and lower liver uptake than 3(S)-BMIPP in fasted rats. The aim of this study was to determine if these differences in myocardial and liver uptake also occur in humans. Methods: Iodine-123-labeled 3(R)-BMIPP and 3(S)-BMIPP isomers were injected at rest, on two separate days, in six patients with stable coronary artery disease. Dual-head, whole-body scintigraphy was performed 20 min and 3 hr after injection. SPECT cardiac imaging was performed 60 min after injection. Results: Myocardial activity averaged (% injected dose +/- s.d.) 3.15 +/- 0.49 versus 3.01 +/- 0.44 at 20 min (p = ns) and 2.64 +/- 0.38 versus 2.55 +/- 0.41 at 3 hr postinjection (p = ns) for the 3(R)-BMIPP and 3(S)-BMIPP isomers, respectively. Liver activity averaged 9.50 +/- 1.18 versus 9.44 +/- 0.66 at 20 min and 5.33 +/- 0.64 versus 5.43 +/- 0.66 at 3 hr, respectively (p = ns). SPECT showed no difference in the distribution of the two isomers between normal and infarcted myocardium, Conclusion: There is no significant difference in myocardial and liver distribution of the 3(R)-BMIPP and 3(S)-BMIPP isomers in humans. C1 Free Univ Brussels, Acad Hosp, Div Nucl Med, B-1090 Brussels, Belgium. Oak Ridge Natl Lab, Div Life Sci, Nucl Med Grp, Oak Ridge, TN USA. RP Franken, PR (reprint author), Free Univ Brussels, Acad Hosp, Div Nucl Med, 101 Laarbeeklaan, B-1090 Brussels, Belgium. NR 17 TC 2 Z9 3 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD OCT PY 1998 VL 39 IS 10 BP 1672 EP 1675 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 126VY UT WOS:000076316200009 PM 9776266 ER PT J AU Breitz, HB Fisher, DR Wessels, BW AF Breitz, HB Fisher, DR Wessels, BW TI Marrow toxicity and radiation absorbed dose estimates from rhenium-186-labeled monoclonal antibody SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE radioimmunotherapy; radiation absorbed dose; myelotoxicity; rhenium-186; monoclonal antibody ID PHASE-I TRIALS; RADIOIMMUNOTHERAPY; CARCINOMA; DOSIMETRY; EXPERIENCE; ANTIGEN; CANCER; MODEL; I/II AB Estimates of radiation absorbed dose to the red marrow (RM) would be valuable in treatment planning for radioimmunotherapy if they could show a correlation with clinical toxicity. In this study, a correlation analysis was performed to determine whether estimates of radiation absorbed dose to the bone marrow could accurately predict marrow toxicity in patients who had received Re-186-labeled monoclonal antibody. Methods: White blood cell and platelet count data from 25 patients who received Re-186-NR-LU-10 during Phase I radioimmunotherapy trials were analyzed, and the toxicity grade, the fraction of the baseline counts at the nadir (percentage baseline) and the actual nadir were used as the indicators of marrow toxicity. Toxicity was correlated with various predictors of toxicity. These predictors included the absorbed dose to RM, the absorbed dose to whole body (WB) and the total radioactivity administered. Results: Percentage baseline and grade of white blood cells and platelets all showed a moderate correlation with absorbed dose and radioactivity administered (normalized for body size). The percentage baseline platelet count was the indicator of toxicity that achieved the highest correlation with the various predictors of toxicity (r = 0.73-0.79). The estimated RM absorbed dose was not a better predictor of toxicity than either the WE dose or the total radioactivity administered. There was substantial variation in the blood count response of the patients who were administered similar radioactivity doses and who had similar absorbed dose estimates. Conclusion: Although there was a moderately good correlation of toxicity with dose, the value of the dose estimates in predicting toxicity is limited by the patient-to-patient variability in response to internally administered radioactivity. In this analysis of patients receiving Re-186-labeled monoclonal antibody, a moderate correlation of toxicity with dose was observed but marrow dose was of limited use in predicting toxicity for individual patients. C1 Virginia Mason Med Ctr, NeoRx Virginia Mason Clin Res Unit, Seattle, WA 98101 USA. Pacific NW Lab, Hanford Radioisotopes Program, Richland, WA USA. George Washington Univ, Med Ctr, Div Radiat Oncol & Biophys, Washington, DC 20037 USA. RP Breitz, HB (reprint author), Virginia Mason Med Ctr, NeoRx Virginia Mason Clin Res Unit, 1100 9th Ave, Seattle, WA 98101 USA. NR 27 TC 36 Z9 36 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 OCT PY 1998 VL 39 IS 10 BP 1746 EP 1751 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 126VY UT WOS:000076316200024 PM 9776281 ER PT J AU Wang, SJ Lin, WY Chen, MN Chi, CS Chen, JT Ho, WL Hsieh, BT Shen, LH Tsai, ZT Ting, G Mirzadeh, S Knapp, FF AF Wang, SJ Lin, WY Chen, MN Chi, CS Chen, JT Ho, WL Hsieh, BT Shen, LH Tsai, ZT Ting, G Mirzadeh, S Knapp, FF TI Intratumoral injection of rhenium-188 microspheres into an animal model of hepatoma SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE rhenium-188; microsphere; intratumoral injection; hepatoma; biodistribution ID INTERNAL RADIATION-THERAPY; Y-90 GLASS MICROSPHERES; HEPATOCELLULAR-CARCINOMA; LIVER MALIGNANCIES; LIPIODOL; BIODISTRIBUTION; RE-188; ARTERY; TRIAL; RATS AB Intratumoral injection of Y-90 microspheres is a potential alternative in the treatment of primary liver tumor. However, complicated preparation and lack of a gamma ray for imaging are the disadvantages of Y-90, In this study, we used Re-188, a generator-produced radioisotope with 155-keV gamma ray emission, to label microspheres, After intratumoral injection of Re-188 microspheres into rats with hepatoma, biodistributions and survival times were analyzed. Methods: Twelve male rats with hepatoma were killed at 1, 24 and 48 hr (4 rats at each time point) after intratumoral injection of similar to 7.4 MBq 188Re microspheres, Samples of various organs were obtained and used to calculate the tissue concentrations. In addition, 30 male rats bearing hepatoma were divided into two groups (15 rats in each group) to evaluate survival time. Group 1 received intratumoral injection of 37 MBq Re-188 microspheres, whereas Group 2 served as the control group and received an intratumoral injection of 0.1 mi normal saline only. Survival time was calculated from the day of injection to 2 mo after treatment. Results: Radioactivity in the tumor was very high throughout. Biological half-time was 170.8 hr. Radioactivity in the lung was 1.78% injected dose (ID)/g at 1 hr but declined rapidly over time. The concentration in the urine was similar to 6.14% ID/ml after the first hour and rapidly declined thereafter. The concentrations of radioactivity in other organs, such as normal liver, muscle, spleen, bone, testis and whole blood, were quite low throughout the study. Twelve of 15 (80%) of rats survived over 60 days after intratumoral injection of Re-188 microspheres, whereas only 4 of 15 (26.7%) survived more than 60 days after injection of normal saline only. The difference between the groups was significant (p < 0.05). Conclusion: Rhenium-188 offers cost-effectiveness, on-site availability, short half-life, energetic beta particle, emission of gamma photons for imaging, easy preparation, easy clinical administration and apparent lack of radiation leakage from the treated tumor. Direct intratumoral injection of Re-188 microspheres is extremely attractive as a clinical therapeutic alternative in hepatoma patients. C1 Taichung Vet Gen Hosp, Dept Nucl Med, Taichung 407, Taiwan. Taichung Vet Gen Hosp, Dept Pediat, Taichung 407, Taiwan. Taichung Vet Gen Hosp, Dept Pathol, Taichung 407, Taiwan. Inst Nucl Energy Res, Lungtan 32500, Taiwan. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Wang, SJ (reprint author), Taichung Vet Gen Hosp, Dept Nucl Med, Sec 3,Taichung Harbor Rd, Taichung 407, Taiwan. NR 24 TC 22 Z9 23 U1 1 U2 4 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 OCT PY 1998 VL 39 IS 10 BP 1752 EP 1757 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 126VY UT WOS:000076316200025 PM 9776282 ER PT J AU Potra, FA Sheng, R AF Potra, FA Sheng, R TI Superlinear convergence of interior-point algorithms for semidefinite programming SO JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS LA English DT Article DE semidefinite programming; path-following algorithms; infeasible interior-point algorithms; polynomiality; superlinear convergence AB We prove the superlinear convergence of the primal-dual infeasible interior-point path-following algorithm proposed recently by Kojima, Shida, and Shindoh and by the present authors, under two conditions: (i) the semidefinite programming problem has a strictly complementary solution; (ii) the size of the central path neighborhood approaches zero. The nondegeneracy condition suggested by Kojima, Shida, and Shindoh is not used in our analysis. Our result implies that the modified algorithm of Kojima, Shida, and Shindoh, which enforces condition (ii) by using additional corrector steps, has superlinear convergence under the standard assumption of strict complementarity. Finally, we point out that condition (ii) can be made weaker and show the superlinear convergence under the strict complementarity assumption and a weaker condition than (ii). C1 Univ Iowa, Dept Math, Iowa City, IA 52242 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Potra, FA (reprint author), Univ Iowa, Dept Math, Iowa City, IA 52242 USA. NR 15 TC 14 Z9 14 U1 0 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-3239 J9 J OPTIMIZ THEORY APP JI J. Optim. Theory Appl. PD OCT PY 1998 VL 99 IS 1 BP 103 EP 119 DI 10.1023/A:1021700210959 PG 17 WC Operations Research & Management Science; Mathematics, Applied SC Operations Research & Management Science; Mathematics GA 132DC UT WOS:000076614100006 ER PT J AU Richter, KW AF Richter, KW TI The ternary In-Ni-Sb phase diagram in the vicinity of the binary In-Ni system SO JOURNAL OF PHASE EQUILIBRIA LA English DT Article AB The central part of the In-Ni phase diagram (0.45 less than or equal to X-ln less than or equal to 0.60) was reinvestigated and the adjoining part of the ternary In-Ni-Sb phase diagram was studied experimentally, The investigation included thermal analyses (DTA), x-ray powder diffraction, and microprobe studies (EPMA), The ternary equilibrium phase relations were studied for three isothermal sections at 750, 825, and 900 degrees C, Four new invariant ternary phase reactions were identified in the temperature range between 805 and 895 degrees C, A complete reaction scheme was constructed in the corresponding composition range, and the liquidus surface was derived from DTA data, The lattice parameter of the solid solution of Sb in CoSn-type NiIn was studied as a function of composition by means of powder diffraction using the Guinier-Huber technique. C1 Univ Vienna, Inst Inorgan Chem, A-1090 Vienna, Austria. RP Richter, KW (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RI Richter, Klaus/D-9869-2013; OI Richter, Klaus/0000-0001-7128-6956 NR 16 TC 4 Z9 4 U1 2 U2 6 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1054-9714 J9 J PHASE EQUILIB JI J. Phase Equilib. PD OCT PY 1998 VL 19 IS 5 BP 455 EP 465 DI 10.1361/105497198770341941 PG 11 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 128WJ UT WOS:000076431100009 ER PT J AU Robinson, DH Arrigo, KR Kolber, Z Gosselin, M Sullivan, CW AF Robinson, DH Arrigo, KR Kolber, Z Gosselin, M Sullivan, CW TI Photophysiological evidence of nutrient limitation of platelet ice algae in McMurdo Sound, Antarctica SO JOURNAL OF PHYCOLOGY LA English DT Article DE Antarctic; nutrient limitation; photoacclimation; pump-probe fluorometry; sea ice algae ID PHOTOSYNTHESIS-IRRADIANCE RELATIONSHIPS; DENSE MICROALGAL BLOOM; SEA-ICE; MICROBIAL COMMUNITIES; CARBON ASSIMILATION; HIGH-RESOLUTION; SPECTRAL IRRADIANCE; ENERGY-CONVERSION; LIGHT-ABSORPTION; MARINE DIATOMS AB Seasonally changing photophysiological and biochemical characteristics of sea ice microalgae are interpreted with respect to light availability and measurements of nutrient concentration made at high vertical resolution (12.5 cm) during a dense bloom in the platelet ice layer of McMurdo Sound during a 6-week study in austral spring of 1989. Platelet ice algae remained highly shade adapted throughout the spring as shown by their low photoadaptive index (E-k, 3.7-8.4 mu mol photons.m(-2).s(-1)), low mean specific absorption coefficient (<0.009 m(2) mg(-1) Chl a), high optical cross-sectional area of photosystem II (sigma(PSII) 3.0-8.2), and high molar ratio of fucoxanthin:chlorophyll a (mean 1.62 +/- 0.25 SD). Between 24 October and 8 November, the algae exhibited a photoacclimative response that was marked by a 30% decrease in photosynthetic efficiency (alpha(B)), a 75% decrease in maximum photosynthetic rate (P-m(B)), and a 60% increase in sigma(PSII). The photochemical conversion efficiency at photosystem II (F-v/F-m = ca. 0.5) and the quantum yield of photosynthesis (empty set(C) = 0.062-0.078 mol C mol(-1) photons) were ca. 80% of their maximal values. After 8 November, changes in algal photophysiology and biochemistry, which were inconsistent with a photoacclimation response, suggest that tice platelet ice alg-ae near the platelet/congelation ice interface became increasingly nutrient limited. The number of pennate diatoms increased threefold to 150 X 10(9) cells m(-3) between 8 and 14 November, then remained unchanged throughout the remainder of the field season. Following the increase in cell number, F-v/F-m, empty set(C), and C:Chla decreased by >40%, sigma(PSII) increased by 70%; and the biochemical ratios C:N and C:Si increased 25%-30%. Nutrient depletion was apparent from the high-resolution vertical profiles, but nutrient concentrations limiting algal growth were not observed. However, nutrient concentrations at the likely site of nutrient limitation near the platelet/congelation ice interface were not measured, indicating that higher resolution sampling is necessary to fully characterize this highly variable habitat. C1 NASA, Univ Space Res Assoc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Quebec, Dept Oceanog, Rimouski, PQ G5L 3A1, Canada. Univ So Calif, Los Angeles, CA 90089 USA. RP Robinson, DH (reprint author), NASA, Univ Space Res Assoc, Goddard Space Flight Ctr, Code 971, Greenbelt, MD 20771 USA. EM dale@neptune.gsfc.nasa.gov RI Gosselin, Michel/B-4477-2014 OI Gosselin, Michel/0000-0002-1044-0793 NR 49 TC 27 Z9 29 U1 2 U2 13 PU PHYCOLOGICAL SOC AMER INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0022-3646 J9 J PHYCOL JI J. Phycol. PD OCT PY 1998 VL 34 IS 5 BP 788 EP 797 DI 10.1046/j.1529-8817.1998.340788.x PG 10 WC Plant Sciences; Marine & Freshwater Biology SC Plant Sciences; Marine & Freshwater Biology GA 133AQ UT WOS:000076664600011 ER PT J AU McDaniel, AH Allendorf, MD AF McDaniel, AH Allendorf, MD TI Flow-tube investigation of the high-temperature reaction between BCl3 and NH3 SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID CHEMICAL VAPOR-DEPOSITION; BORON-NITRIDE; MATHEMATICAL-MODEL; GAS-PHASE; KINETICS; THERMOCHEMISTRY; MOLECULES; COMPLEXES; REACTORS; SPECTRA AB The reaction between BCl3 and NH3 to produce dichloroboramine (Cl2BNH2) and HCl was probed using a flow-tube reactor interfaced to a molecular-beam mass-sampling system. A composite method that couples the detailed simulation of the fluid mechanics and chemical reactions occurring in the flow tube to an algorithm for nonlinear least-squares optimization was used to extract the kinetic parameters from the experiment. The rate constant for this gas-phase reaction is k (cm(3) mol(-1) s(-1)) = 4.21 x 10(11) exp[-(8350 cal mol(-1))/(RT)] with an estimated uncertainty of 10-15% over the temperature range 670-920 K. The results indicate that surface reactions involving BCl3 and NH3 occur in the flow tube, but their contributions to the observed chemical behavior of the system can be quantified and therefore do not affect the kinetic measurements reported here. In addition, the low-energy barrier to this gas-phase reaction has important implications for the chemical vapor deposition of boron nitride from BCl3 and NH3. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Allendorf, MD (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM mdallen@sandia.gov NR 41 TC 17 Z9 18 U1 1 U2 1 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 OCT 1 PY 1998 VL 102 IS 40 BP 7804 EP 7812 DI 10.1021/jp981846g PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 127ZJ UT WOS:000076380500012 ER PT J AU Balatsky, AV AF Balatsky, AV TI Spontaneous time reversal and parity breaking in a d(x(2)-y(2))-wave superconductor with magnetic impurities SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS ID D-WAVE SUPERCONDUCTOR; VORTEX STATE AB It is argued that the d(x2-y2) superconductor exhibits a transition into the d(x2-y2) + id(xy) state in the presence of magnetic impurities in certain conditions. Linear coupling beta een impurity magnetization and the d(xy) component drives this transition. Violation of time-reversal symmetry and parity occurs spontaneously via the second order transition. In the ordered phase both impurity magnetization and d(xy) component of the order parameter develop and are proportional to each other. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Balatsky, AV (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 18 TC 7 Z9 8 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1689 EP 1693 DI 10.1016/S0022-3697(98)00084-5 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500005 ER PT J AU Emery, VJ Kivelson, SA AF Emery, VJ Kivelson, SA TI Crossovers and phase coherence in cuprate superconductors SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE doped insulator; charge inhomogeneity; superconductivity ID HIGH-TEMPERATURE SUPERCONDUCTORS; T-C SUPERCONDUCTORS; PENETRATION-DEPTH; NORMAL-STATE; SINGLE-CRYSTALS; GAP ANISOTROPY; SPIN-GAP; BI2SR2CACU2O8+DELTA; SYSTEM; MODEL AB High temperature superconductivity is a property of doped antiferromagnetic insulators. The electronic structure is inhomogeneous on short length and rime scales, and, as the temperature decreases, it evolves via two crossovers, before long range superconducting order is achieved. Except possibly for overdoped materials, pairing and phase coherence occur at different temperatures, and phase fluctuations determine both T-c and the temperature dependence of the superfluid density for a wide range of doping. A mechanism for obtaining a high pairing scale in a short coherence length material with a strong poorly-screened Coulomb interaction is described. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. RP Emery, VJ (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM emery@bnl.gov NR 38 TC 27 Z9 27 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1705 EP 1710 DI 10.1016/S0022-3697(98)00087-0 PG 6 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500008 ER PT J AU Schmalian, J Pines, D Stojkovic, B AF Schmalian, J Pines, D Stojkovic, B TI Weak pseudogap behavior in the underdoped cuprate superconductors SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE Fermi liquid; cuprate superconductors; pseudogap ID ANTIFERROMAGNETIC FERMI-LIQUID; ELECTRONIC-STRUCTURE; NORMAL-STATE; BI2SR2CACU2O8+DELTA; YBA2CU3O7; GAP AB We report on an exact solution of the nearly antiferromagnetic Fermi liquid spin fermion model in the limit pi T >> omega(sf), which demonstrates that the broad high energy features found in ARPES measurements of the spectral density of the underdoped superconductors are determined by strong antiferromagnetic (AF) correlations and precursor effects of an SDW state. We show that the onset temperature, T-cr, of weak pseudogap (pseudoscaling) behavior is determined by the strength, xi, of the AF correlations, and obtain with xi(T-cr) approximate to 2 the generic changes in low frequency magnetic behavior seen in NMR experiments, confirming the Barzykin and Pines crossover criterion. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Illinois, Loomis Lab Phys, Urbana, IL 61801 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Schmalian, J (reprint author), Univ Illinois, Loomis Lab Phys, 1110 W Green St, Urbana, IL 61801 USA. EM schmal@physics.uiuc.edu RI Schmalian, Joerg/H-2313-2011 NR 20 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1764 EP 1768 DI 10.1016/S0022-3697(98)00104-8 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500020 ER PT J AU Blackstead, HA Cooley, JC Dow, JD Hults, WL Malik, SK Pulling, DB Smith, JL Yelon, WB AF Blackstead, HA Cooley, JC Dow, JD Hults, WL Malik, SK Pulling, DB Smith, JL Yelon, WB TI Evidence of pair-breaking by Pr-Ba in Y1-yPryBa2Cu3O7 SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE superconductivity; rare-earths; PrBa2Cu3O7 ID SUPERCONDUCTIVITY; PRBA2CU3O7; DEPENDENCE AB Microwave surface impedance, neutron diffraction, and electron spin resonance data provide evidence that the magnetic pair-breaking defect associated with Pr in Y1-yPryBa2Cu3O7 is Pr on the Be site, not on the rare-earth site. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Arizona State Univ, Dept Phys, Tempe, AZ 85287 USA. Tata Inst Fundamental Res, Mumbai, India. Univ Missouri Res Reactor, Columbia, MO 65211 USA. RP Dow, JD (reprint author), 6031 E Cholla Lane, Scottsdale, AZ 85253 USA. RI Cooley, Jason/E-4163-2013 NR 18 TC 5 Z9 5 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1798 EP 1800 DI 10.1016/S0022-3697(98)00107-3 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500028 ER PT J AU Brandow, B AF Brandow, B TI Characteristic features of the exotic superconductors: A summary SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE exotic superconductors; phenomenology ID HEAVY-FERMION; BCS SUPERCONDUCTIVITY; BOSE-CONDENSATION; RESISTIVITY; MECHANISM; EVOLUTION; BEHAVIOR; LIFETIME; CUPRATE; DENSITY AB We summarize the results of a comprehensive examination of the characteristic features of the exotic superconductors, the superconductors so-labelled by Uemura and co-workers. In both the electronic and crystal chemistry properties, we find anomalous features which appear to be "universal" for these materials, as well as other features which are clearly not universal but common enough to be considered typical fur these materials. Some implications of these anomalies are discussed. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Brandow, B (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. NR 20 TC 0 Z9 0 U1 2 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1804 EP 1807 DI 10.1016/S0022-3697(98)00109-7 PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500030 ER PT J AU Vilk, YM Allen, S Touchette, H Moukouri, S Chen, L Tremblay, AMS AF Vilk, YM Allen, S Touchette, H Moukouri, S Chen, L Tremblay, AMS TI Attractive Hubbard model and single-particle pseudogap caused by classical pairing fluctuations in two-dimensions SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE Hubbard model; single-particle pseudogap; quasiparticles; fluctuations ID NORMAL-STATE; SUPERCONDUCTORS; GAP AB It is shown that in the two-dimensional attractive Hubbard model, the mean-field phase transition is replaced by a renormalized classical regime of fluctuations where a pseudogap opens up in the single-particle spectral weight. It is argued that this pseudogap and precursors of the ordered state quasiparticles can occur only in strongly anisotropic quasi-two-dimensional materials. This precursor phenomenon differs from preformed local pairs. Further, while critical antiferromagnetic fluctuations would also lead to a pseudogap in the repulsive model, there are some important differences with thr superconducting case. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Sherbrooke, Dept Phys, Sherbrooke, PQ J1K 2R1, Canada. Univ Sherbrooke, Ctr Rech Phys Solide, Sherbrooke, PQ J1K 2R1, Canada. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Tremblay, AMS (reprint author), Univ Sherbrooke, Dept Phys, Sherbrooke, PQ J1K 2R1, Canada. NR 14 TC 16 Z9 16 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1873 EP 1875 DI 10.1016/S0022-3697(98)00129-2 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500050 ER PT J AU Ding, H Campuzano, JC Norman, MR Randeria, M Yokoya, T Takahashi, T Takeuchi, T Mochiku, T Kadowaki, K Guptasarma, P Hinks, DG AF Ding, H Campuzano, JC Norman, MR Randeria, M Yokoya, T Takahashi, T Takeuchi, T Mochiku, T Kadowaki, K Guptasarma, P Hinks, DG TI ARPES study of the superconducting gap and pseudogap in Bi2Sr2CaCu2O8+x SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MA DE high temperature superconductors; angle-resolved photoemission; superconductivity gap pseudogap ID NORMAL-STATE; ANISOTROPY AB In this paper, we review some of our ARPES results on the superconducting and pseudo gaps in Bi2Sr2CaCu2O8+x. We find that optimally and overdoped samples exhibit a d-wave gap, which closer at the same temperature, T-c, for all k points. In underdoped samples, a leading edge gap is Found up to a temperature T* > T-c. We find that T* scales with the maximum low temperature gap, increasing as the doping is reduced. The momentum dependence of the pseudogap is similar to that of the superconducting gap: however, the pseudogap closes at different temperatures for different k points. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Nagoya Univ, Dept Crystalline Mat Sci, Nagoya, Aichi 46401, Japan. Natl Res Inst Met, Ibaraki 305, Japan. Univ Tsukuba, Inst Mat Sci, Ibaraki 305, Japan. Tohoku Univ, Dept Phys, Sendai, Miyagi 980, Japan. RP Ding, H (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Takahashi, Takashi/E-5080-2010; Tohoku, Arpes/A-4890-2010; Campuzano, Juan Carlos/G-4358-2012; Norman, Michael/C-3644-2013; YOKOYA, Takayoshi/B-1478-2011; OI Ding, Hong/0000-0003-4422-9248 NR 13 TC 52 Z9 53 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1888 EP 1891 DI 10.1016/S0022-3697(98)00136-X PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500054 ER PT J AU Fujimori, A Ino, A Mizokawa, T Kim, C Shen, ZX Sasagawa, T Kimura, T Kishio, K Takaba, M Tamasaku, K Eisaki, H Uchidau, S AF Fujimori, A Ino, A Mizokawa, T Kim, C Shen, ZX Sasagawa, T Kimura, T Kishio, K Takaba, M Tamasaku, K Eisaki, H Uchidau, S TI Chemical potential shift, density of states and Fermi surfaces in overdoped and underdoped La2-xSrxCuO4 SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MA DE La2-xSrxCuO4; photoemission; ARPES; pseudogap; Fermi surface; chemical potential ID ELECTRONIC SPECIFIC-HEAT; T-C SUPERCONDUCTORS; TEMPERATURE; TRANSITIONS; DEPENDENCE; MODEL; GAP AB We have made photoemission studies of La2-xSrxCuO4 (LSCO) and found the following: (1) suppression of the chemical potential (mu) shift fur small x indicates a breakdown of the Fermi-liquid picture in the underdoped regime and suggests the opening of a pseudogap: (2) valence band spectra have indeed shown a pseudogap whose magnitude increases with decreasing x. simultaneously the density of states (DOS) at mu diminishes;(3) ARPES measurements have revealed changes from an electron-like Fermi surface in the overdoped regime to a hole-like one in the underdoped regime. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 113, Japan. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Tokyo, Dept Superconduct, Bunkyo Ku, Tokyo 113, Japan. RP Fujimori, A (reprint author), Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 113, Japan. RI Sasagawa, Takao/E-6666-2014; Mizokawa, Takashi/E-3302-2015; Tamasaku, Kenji/N-7907-2015 OI Sasagawa, Takao/0000-0003-0149-6696; Mizokawa, Takashi/0000-0002-7682-2348; NR 30 TC 14 Z9 14 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1892 EP 1896 DI 10.1016/S0022-3697(98)00137-1 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500055 ER PT J AU Norman, MR Ding, H Randeria, M Campuzano, JC AF Norman, MR Ding, H Randeria, M Campuzano, JC TI Electron self-energy of high temperature superconductors as revealed by angle-resolved photoemission SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MA DE self energy; photoemission; superconductivity ID GAP ANISOTROPY; NORMAL-STATE; FERMI-SURFACE; BI2SR2CACU2O8+DELTA; MOMENTUM; YBA2CU3O6+X; DEPENDENCE; DISPERSION; EVOLUTION; SYSTEM AB In this paper, we review some of the work our group has done in the past few years to obtain the electron self-energy of high temperature superconductors by analysis of angle-resolved photoemission data. We focus on three examples which have revealed: (1) a d-wave superconducting gap, (2) a collective mode in the superconducting state, and (3) pairing correlations in the pseudogap phase. In each case, although a novel result is obtained which captures the essence of the data, the conventional physics used leads to an incomplete picture. This indicates that new physics needs to be developed to obtain a proper understanding of these materials. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. RP Norman, MR (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Campuzano, Juan Carlos/G-4358-2012; Norman, Michael/C-3644-2013; OI Ding, Hong/0000-0003-4422-9248 NR 33 TC 0 Z9 0 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1902 EP 1906 DI 10.1016/S0022-3697(98)00144-9 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500057 ER PT J AU Dessau, DS Saitoh, T Villella, P Park, CH Shen, ZX Moritomo, Y Tokura, Y AF Dessau, DS Saitoh, T Villella, P Park, CH Shen, ZX Moritomo, Y Tokura, Y TI Comparison of the measured electronic structure of the colossal magnetoresistive manganites and high T-c superconductors: Band structure, photoemission lineshapes, and a pseudogap SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE colossal magnetoresistance; electronic structure; photoemission; pseudogap ID NORMAL-STATE; BI2SR2CACU2O8+DELTA; TEMPERATURE AB We have used high energy-resolution angle-resolved photoemission spectroscopy to study the k-dependent electronic structure of single-crystalline samples of the manganese-based perovskites as a function of doping level, temperature, and layer number. An especially important aspect of the data is a temperature and sample-type dependent pseudogap which drastically depletes the spectral weight at E-F. In contrast to the pseudogap observed in the high T-c superconductors, the pseudogap in the manganites is essentially isotropic in k-space, implying that a local effect such as a lattice distortion should be responsible. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. JRCAT, Tsukuba, Ibaraki, Japan. RP Dessau, DS (reprint author), Univ Colorado, Dept Phys, Boulder, CO 80309 USA. RI Saitoh, Tomohiko/G-5922-2012; Tokura, Yoshinori/C-7352-2009; OI moritomo, yutaka/0000-0001-6584-7489 NR 15 TC 2 Z9 2 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1917 EP 1920 DI 10.1016/S0022-3697(98)00149-8 PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500060 ER PT J AU Blumberg, G Klein, MV Kadowaki, K Kendziora, C Guptasarma, P Hinks, D AF Blumberg, G Klein, MV Kadowaki, K Kendziora, C Guptasarma, P Hinks, D TI Evolution of magnetic and superconducting fluctuations with doping of high-T-c superconductors: An electronic Raman scattering study SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MA DE Raman scattering; antiferromagnetic correlations; superconducting order ID CUPRATE ANTIFERROMAGNETIC INSULATORS; MOTT-HUBBARD SYSTEMS; SINGLE-CRYSTAL; NORMAL-STATE; BOSE CONDENSATION; SPIN DYNAMICS; GAP; BI2SR2CACU2O8+DELTA; YBA2CU3O7-DELTA; CONTINUUM AB For YBa2Cu3O6+delta and Bi2Sr2CaCu2O8+/-delta superconductors, electronic Raman scattering from high- and low-energy excitations has been studied in relation to the hole doping level, temperature and energy of the incident photons. For underdoped superconductors, it is concluded that short range antiferromagnetic (AF) correlations persist with hole doping and doped single holes are incoherent in the AF environment. Above the superconducting (SC) transition temperature T-c, the system exhibits a sharp Raman resonance of B-1g symmetry and about 75 meV energy and a pseudogap for electron-hole excitations below 75 meV, a manifestation of a partially coherent state forming from doped incoherent quasi-particles. The occupancy of the coherent state increases with cooling until phase ordering at T-c produces a global SC state. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Illinois, NSF Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Inst Chem Phys & Biophys, EE-0001 Tallinn, Estonia. Univ Tsukuba, Inst Mat Sci, Tsukuba, Ibaraki 305, Japan. USN, Res Lab, Washington, DC 20375 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Univ Illinois, NSF Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. NR 45 TC 20 Z9 20 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 EI 1879-2553 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1932 EP 1936 DI 10.1016/S0022-3697(98)00135-8 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500064 ER PT J AU Homes, CC Peng, JL Greene, RL Clayman, BP AF Homes, CC Peng, JL Greene, RL Clayman, BP TI Optical conductivity of Nd1.85Ce0.15CuO4: Strength of the condensate SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS ID TEMPERATURE-DEPENDENCE; PENETRATION-DEPTH; SINGLE-CRYSTALS; THIN-FILMS; HEAT JUMP; TRANSPORT; PLANE; TC; ND AB The ab-plane reflectance of a Nd1.85Ce0.15CuO4 single crystal (T-c = 23 K) has been measured from approximate to 30 to 9500 cm(-1) above and below T-c, and the optical properties calculated from a Kramers-Kronig analysis. A rich phonon spectrum is observed with some new spectral features appearing below approximate to 100 K. The normal-state optical conductivity may be described by a Drude-like component and an overdamped mid infrared component. Below T-c the plasma frequency of the condensate is omega(pS) approximate to 10 000 cm(-1). The London penetration depth is determined to be lambda(ab) = 1600 +/- 100 Angstrom, which places it well off the Uemura line. Estimates of the electron-phonon coupling from normal-state transport measurements yield lambda(tr) < 0.5. The small values for the penetration depth and the electron-phonon coupling constant suggest that the superconductivity in this material is not due to the electron-phonon mechanism, and is different to that in other hole-doped superconducting cuprates. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Maryland, Ctr Supercond Res, Dept Phys & Astron, College Pk, MD 20742 USA. Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. RP Homes, CC (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM homes@bnl.gov NR 21 TC 1 Z9 1 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 1979 EP 1981 DI 10.1016/S0022-3697(98)00160-7 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500075 ER PT J AU Rubhausen, M Guptasarma, P Hinks, DG Klein, MV AF Rubhausen, M Guptasarma, P Hinks, DG Klein, MV TI Spin and charge excitations in optimally doped Bi2Sr2CaCu2O8+delta SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE Raman spectroscopy; antiferromagnetic; superconducting ID MOTT-HUBBARD SYSTEMS; RAMAN-SCATTERING; ENERGY EXCITATIONS; LIGHT-SCATTERING; SINGLE-CRYSTALS; SUPERCONDUCTORS; GAP AB We present Raman spectra of low and high-energy charge and spin excitations in Bi2Sr2CaCu2O8-delta single crystals with an optimized critical temperature of 95 K. The prominent feature of the high-energy background at around 250 meV is a rearrangement of spectral weight in B-1g and A(1g) + B-2g symmetry below the critical temperature, similar to the observations in underdoped and optimally doped Y-123 compounds. In the low-energy region, which is influenced by the effects at higher energies, a gap feature in B-1g symmetry is observed yielding a value for the magnitude of the superconducting order parameter of Delta = 34 meV. This gap feature is influenced by the orthorhombicity of the crystals and except for a small loss of spectral weight below 25 meV, no gap Feature is visible in A(1g) scattering geometry. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Illinois, Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. Univ Hamburg, Inst Angew Phys, D-20355 Hamburg, Germany. Univ Hamburg, Zentrum Mikrostrukturforsch, D-20355 Hamburg, Germany. Argonne Natl Lab, STCS, MSD, Argonne, IL 60439 USA. RP Klein, MV (reprint author), Univ Illinois, Sci & Technol Ctr Superconduct, 104 S Goodwin Ave, Urbana, IL 61801 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2009 EP 2011 DI 10.1016/S0022-3697(98)00156-5 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500085 ER PT J AU Iavarone, M De Wilde, Y Guptasarma, P Hinks, DG Crabtree, GW Canfield, PC AF Iavarone, M De Wilde, Y Guptasarma, P Hinks, DG Crabtree, GW Canfield, PC TI STM investigation of BSCCO 2212 and borocarbide materials SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE borocarbide; spectroscopic scanning tunneling microscope; magnetic ions ID HIGH-TEMPERATURE SUPERCONDUCTORS; VACUUM TUNNELING SPECTROSCOPY; THIN-FILMS; ENERGY-GAP; BI2SR2CACU2O8+DELTA; DEPENDENCE; YNI2B2C; DISPERSION; LUNI2B2C; SPECTRA AB We present spectroscopic Scanning Tunneling Microscope (STM) measurements performed at 4.2 K on BSCCO 2212 single crystals and Y, Lu and Er based borocarbide compounds. The conductance versus voltage spectra on BSCCO 2212 reveal a reproducible dip feature near e\V\ = 2 Delta, for both voltage polarities pointing to a strong coupling origin of the feature. The conductance spectra obtained on YNi2B2C thin films and LuNi2B2C single crystals are similar and correspond to a BCS ratio of 3.2 indicating weak coupling superconductivity in these compounds. On Er Ni2B2C single crystals, the conductance spectra show a pronounced broadening compared to the spectra obtained on LuNi2B2C and YNi2B2C, which is attributed to the pair-breaking effect due to the Er magnetic ions. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Sci & Technol Ctr Superconduct, Div Mat Sci, Argonne, IL 60439 USA. Univ Naples Federico II, Fac Ingn, Dipartimento Sci Fis, INFM, I-80125 Naples, Italy. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP De Wilde, Y (reprint author), Argonne Natl Lab, Sci & Technol Ctr Superconduct, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Iavarone, Maria/C-3628-2008; Canfield, Paul/H-2698-2014; OI De Wilde, Yannick/0000-0002-5973-1460 NR 26 TC 3 Z9 3 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2030 EP 2033 DI 10.1016/S0022-3697(98)00171-1 PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500091 ER PT J AU Krishana, K Ong, NP Li, Q Gu, GD Koshizu, N AF Krishana, K Ong, NP Li, Q Gu, GD Koshizu, N TI Evidence for a new transition in Bi2Sr2CaCu2O8 from quasi-particle heat transport in field SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE thermal conductivity; phase transitions ID YBA2CU3O6.95; CONDUCTIVITY; SCATTERING AB The held profile of the in-plane thermal conductivity kappa in Bi2Sr2CaCu2O8 displays a striking anomaly below 20 K. At a 'kink'' field H-k, the profile exhibits a sharp break in slope, followed by a plateau in which kappa is field independent. The anomaly suggests a phase transition of the condensate to a state in which the quasi-particle heat current is zero. We discuss aspects of the experiment and some recent interpretations. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Princeton Univ, Joseph Henry Labs Phys, Princeton, NJ 08544 USA. Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. Univ New S Wales, Sch Phys, Sydney, NSW 2052, Australia. ISTEC, Superconduct Res Lab, Koto Ku, Tokyo 135, Japan. RP Krishana, K (reprint author), Princeton Univ, Joseph Henry Labs Phys, Princeton, NJ 08544 USA. EM npo@pupgg.princeton.edu NR 15 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2088 EP 2090 DI 10.1016/S0022-3697(98)00179-6 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500106 ER PT J AU Mallozzi, R Corson, J Orenstein, J Eckstein, JN Bozovic, I AF Mallozzi, R Corson, J Orenstein, J Eckstein, JN Bozovic, I TI Terahertz conductivity and c-axis plasma resonance in Bi2Sr2CaCu2O8+delta SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS ID COPPER-OXIDE SUPERCONDUCTORS; QUASI-PARTICLE SCATTERING; VORTEX STATE; PENETRATION DEPTH; YBA2CU3O6.95; PSEUDOGAP; COHERENCE; PHASE AB We report measurements of the zero-field c-axis plasma resonance and ab-plane terahertz conductivity in a thin film of Bi2Sr2CaCu2O8+delta Thr measurements are performed using time-domain transmission spectroscopy in the frequency range 50-700 GHz (1.7-21 cm(-1)). (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Varian Associates Inc, EL Ginzton Res Ctr, Palo Alto, CA 94303 USA. RP Orenstein, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Orenstein, Joseph/I-3451-2015 NR 28 TC 5 Z9 5 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2095 EP 2099 DI 10.1016/S0022-3697(98)00181-4 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500108 ER PT J AU Movshovich, R Jaime, M Hubbard, MA Salamon, MB Balatsky, AV Yoshizaki, R Sarrao, JL AF Movshovich, R Jaime, M Hubbard, MA Salamon, MB Balatsky, AV Yoshizaki, R Sarrao, JL TI Low-temperature phase transition in Bi2Sr2Ca(Cu1-xNix)(2)O-8 SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS ID TIME-REVERSAL SYMMETRY; THERMAL-CONDUCTIVITY; SINGLE-CRYSTALS; SUPERCONDUCTORS; BI2SR2CACU2O8; YBA2CU3O7; NMR; NQR; NI AB We report on the discovery of a low-temperature phase transition in Bi2Sr2Ca(NixCu1-x)(2)O-8 high temperature superconductor. This transition manifests itself as a sharp reduction of the thermal conductivity of the samples at a temperature T-c* approximate to 200 mK. The temperature dependence of the thermal conductivity changes dramatically from nearly quadratic above the transition to T-linear behavior below the transition. Application of a small magnetic field suppresses the low-temperature phase. Such behavior is consistent with appearance of a second bulk low-temperature superconducting state at T-c*. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Illinois, Urbana, IL 61801 USA. Univ Tsukuba, Inst Appl Phys, Cryogen Ctr, Tsukuba, Ibaraki 305, Japan. RP Movshovich, R (reprint author), Univ Calif Los Alamos Natl Lab, MS K764, Los Alamos, NM 87545 USA. RI Jaime, Marcelo/F-3791-2015 OI Jaime, Marcelo/0000-0001-5360-5220 NR 22 TC 5 Z9 6 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2100 EP 2104 DI 10.1016/S0022-3697(98)00182-6 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500109 ER PT J AU Abrikosov, AA AF Abrikosov, AA TI The neutron peak in the extended saddle point model of high temperature superconductors SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE high T-c superconductors; neutron peak; spin-flip neutron scattering; extended saddle point model ID ORDER-PARAMETER; YBA2CU3O6+X; SCATTERING; SINGULARITY AB An explanation is proposed for the maximum at 41 meV in the inelastic spin-flip neutron scattering from YBa2Cu3O7-delta, based on the extended saddle point model developed by the author in his previous works. It is shown that, for appearance of the maximum in the imaginary part of the spin susceptibility, close proximity of the Fermi energy to the extended saddle point is necessary. The energy of the maximum is then close to 2 Delta(max), in agreement with experiment. Theoretical and experimental evidence concerning the energy of the extended saddle point (Rat region) is discussed. Different limiting cases are calculated. A proof is given within the present model that interaction in the Final state is small, and hence no collective modes are formed. A general discussion of the experimental situation is presented. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Abrikosov, AA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2129 EP 2134 DI 10.1016/S0022-3697(98)00194-2 PG 6 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500116 ER PT J AU Mook, HA Dai, P Hunt, RD Dogan, F AF Mook, HA Dai, P Hunt, RD Dogan, F TI Neuron scattering studies of the magnetic fluctuations in YBa2Cu3O-(7-delta) SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE neutron scattering; magnetic fluctuations; high T-c superconductivity ID NEUTRON-SCATTERING; YBA2CU3O6+X AB Neutron scattering measurements were made on the spin fluctuations in YBa2Cu3O7-delta for different oxygen doping levels. Incommensurability is clearly observed for oxygen concentrations of 6.6 and 6.7 and is suggested for the 6.93. Measurements of the resonance for the O-6.6 concentration show that it exists in a broadened and less intense form at temperatures much higher than T-c. (C) 1998 Elsevier Science Ltd. All rights reserved. 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 Mook, HA (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Dai, Pengcheng /C-9171-2012 OI Dai, Pengcheng /0000-0002-6088-3170 NR 7 TC 9 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2140 EP 2144 DI 10.1016/S0022-3697(98)00196-6 PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500118 ER PT J AU Tranquada, JM AF Tranquada, JM TI Charge stripes and antiferromagnetism in insulating nickelates and superconducting cuprates SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MA DE antiferromagnetism; layered nickelates and cuprates; change order ID COPPER-OXIDE SUPERCONDUCTORS; MAGNETIC FLUCTUATIONS; SPIN FLUCTUATIONS; LA2-XSRXCUO4; ORDER; PHASE; HOLES; LA1.6-XND0.4SRXCUO4; INSTABILITIES; LA2-XBAXCUO4 AB Neutron and X-ray scattering studies have provided strong evidence for coupled spatial modulations of charge and spin densities in layered nickelates and cuprates. The accumulated results for La2-xSrixNiO4+delta are consistent with the strongly modulated topological-stripe concept. Clues from Nd-doped La2-xSrxCuO4 suggest similar behavior for the cuprates. The experimental results are summarized, and features that conflict with an interpretation based on a Fermi-surface instability are emphasized. A rationalization for the differences in transport properties between the cuprates and nickelates is given. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Tranquada, JM (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM jtran@bnl.gov RI Tranquada, John/A-9832-2009 OI Tranquada, John/0000-0003-4984-8857 NR 38 TC 50 Z9 50 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 EI 1879-2553 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2150 EP 2154 DI 10.1016/S0022-3697(98)00198-X PG 5 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500120 ER PT J AU Moshopoulou, EG Thompson, JD Fisk, Z Sarrao, JL AF Moshopoulou, EG Thompson, JD Fisk, Z Sarrao, JL TI Electron diffraction study of La2Li0.5Cu0.5O4 SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT International Conference on Spectroscopies in Novel Superconductors (SNS'97) CY SEP 14-18, 1997 CL CAPE COD, MASSACHUSETTS DE electron diffraction; lattice distortions; crystal symmetry ID LA2CU0.5LI0.5O4; LA2CU1-XLIXO4; STATE AB La2Li0.5Cu0.5O4 has been investigated by electron diffraction and high resolution electron microscopy at room temperature. Ordering between Li and Cu cations is nearly perfect within the (a, c) plane but there is disorder between Cu and Li cations along the b axis. The detection nf weak reflections which violate the C centering of the Cmmm space group (initially proposed [1] for this compound), indicates that the crystal symmetry allows lattice distortions. The evolution of the structure as a function of the temperature may lead to the determination of whether the low energy singlet-triplet excitation, found in NMR/NQR studies, is coupled with lattice distortions. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. Florida State Univ, Tallahassee, FL 32306 USA. Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RP Moshopoulou, EG (reprint author), Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, POB 1663, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT-DEC PY 1998 VL 59 IS 10-12 BP 2227 EP 2229 DI 10.1016/S0022-3697(98)00220-0 PG 3 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 146YB UT WOS:000077460500140 ER PT J AU Greenlees, PT Amzal, N Butler, PA Cann, KJ Cocks, JFC Hawcroft, D Jones, GD Page, RD Andreev, A Enqvist, T Fallon, P Gall, B Guttormsen, M Helariutta, K Hoellinger, F Jones, PM Julin, R Juutinen, S Kankaanpaa, H Kettunen, H Kuusiniemi, P Leino, M Messelt, S Muikku, M Savelius, A Schiller, A Siem, S Trzaska, WH Tveter, T Uusitalo, J AF Greenlees, PT Amzal, N Butler, PA Cann, KJ Cocks, JFC Hawcroft, D Jones, GD Page, RD Andreev, A Enqvist, T Fallon, P Gall, B Guttormsen, M Helariutta, K Hoellinger, F Jones, PM Julin, R Juutinen, S Kankaanpaa, H Kettunen, H Kuusiniemi, P Leino, M Messelt, S Muikku, M Savelius, A Schiller, A Siem, S Trzaska, WH Tveter, T Uusitalo, J TI First observation of excited states in U-226 SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Letter ID PERFORMANCE; SEPARATOR; NUCLEI AB The technique of recoil-decay tagging has been employed in order to observe excited yrast states in the neutron-deficient nucleus U-226, for the first time. Interleaved bands of positive- and negative-parity states suggest the octupole nature of this nucleus, and the behaviour of the difference in aligned angular momentum between the negative- and positive-parity states with rotational frequency is consistent with that expected of a rotating reflection-asymmetric shape. This represents an extension of the known octupole-deformed nuclei to Z = 92. The interleaved bands of alternating parity are connected by strong electric dipole transitions, and values of \D-0/Q(0)\ extracted from E1/E2 gamma-ray branching ratios, suggest that U-226 possesses one of the largest E1 moments near to the ground state of the nuclei in this region. C1 Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Univ Jyvaskyla, Dept Phys, FIN-40351 Jyvaskyla, Finland. Joint Inst Nucl Res, SU-141980 Dubna, Russia. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Oslo, Dept Phys, N-0316 Oslo, Norway. Ctr Rech Nucl, F-67037 Strasbourg, France. RP Greenlees, PT (reprint author), Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. OI Butler, Peter/0000-0001-6080-9205 NR 13 TC 27 Z9 27 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD OCT PY 1998 VL 24 IS 10 BP L63 EP L70 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 130GN UT WOS:000076512000001 ER PT J AU Yukhimuk, V Voitenko, Y Fedun, V Yukhimuk, A AF Yukhimuk, V Voitenko, Y Fedun, V Yukhimuk, A TI Generation of kinetic Alfven waves by upper-hybrid pump waves SO JOURNAL OF PLASMA PHYSICS LA English DT Article ID MAGNETOSPHERE; TURBULENCE AB The nonlinear mechanism for kinetic-Alfven-wave (KAW) excitation by upper-hybrid waves (UHWs) is discussed. Taking into account perpendicular dispersion of KAWs; caused by effects of finite ion Larmor radius and electron inertia, me examine a new channel for UHW decay, in which a pump UHW decays into another UHW and an ultralow-frequency wave, KAW: UHW --> KAW + UHW. A nonlinear dispersion relation is derived, and the growth rate of the parametric decay instability is calculated for a pump UHW propagating at an arbitrary angle to the back ground magnetic field. We find that the resulting KAWs often have a two-peaked spectrum with different perpendicular dispersions. Using satellite observations, the analytical results are applied to show that the considered process represents an effective mechanism for KAW generation and the consequent spreading of the UHW spectrum in the Earth's magnetosphere and solar corona. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Ukrainian Acad Sci, Main Astron Observ, Dept Space Plasma Phys, UA-252650 Kiev, Ukraine. Kyiv Natl Univ, Dept Space Phys & Astron, UA-252022 Kiev, Ukraine. RP Yukhimuk, V (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Fedun, Viktor/M-9244-2013 NR 24 TC 8 Z9 8 U1 1 U2 1 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0022-3778 J9 J PLASMA PHYS JI J. Plasma Phys. PD OCT PY 1998 VL 60 BP 485 EP 495 DI 10.1017/S0022377898006874 PN 3 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 146YD UT WOS:000077460700003 ER PT J AU Pyda, M Boller, A Grebowicz, J Chuah, H Lebedev, BV Wunderlich, B AF Pyda, M Boller, A Grebowicz, J Chuah, H Lebedev, BV Wunderlich, B TI Heat capacity of poly(trimethylene terephthalate) SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE heat capacity; poly(trimethylene terephthalate); entropy; enthalpy; free enthalpy; heats of transition; glass transition; melting; crystallinity; rigid-amorphous fraction ID DIFFERENTIAL SCANNING CALORIMETRY; TEMPERATURE-MODULATED CALORIMETRY; HIGH MELTING POLYMERS; POLY(ETHYLENE-TEREPHTHALATE) FIBERS; LINEAR MACROMOLECULES; GLASS-TRANSITION; PHENYLENE GROUPS; ADDITION SCHEME; CELL ASYMMETRY; LIQUID AB The heat capacity of poly(trimethylene terephthalate) (PTT) has been measured using adiabatic calorimetry, standard differential scanning calorimetry (DSC), and temperature-modulated differential scanning calorimetry (TMDSC). The heat capacities of the solid and liquid states of semicrystalline PTT are reported from 5 to 570 K. The semicrystalline PTT has a glass transition temperature of 331 K. Between 340 and 480 K, PTT can show exothermic ordering depending on the prior degree of crystallization. The melting endotherm of semicrystalline samples occurs between 480 and 505 K, with a typical onset temperature of 489 K (216 degrees C). The heat of fusion of the semicrystalline samples is about 15 kJ mol(-1). For 100% crystalline PTT the heat of fusion is estimated to be 30 +/- 2 kJ mol(-1). The heat capacity of solid PTT is linked to an approximate group vibrational spectrum and the Tarasov equation is used to estimate the heat capacity contribution due to skeletal vibrations (theta(1) = 550.5 K and theta(2) = theta(3) = 51 K, N-skeletal = 19). The calculated and experimental heat capacities agree to better than +/-3% between 5 and 300 K. The experimental heat capacities of liquid PTT can be expressed by: C-p(L) (exp) = 211.6 + 0.434 T J K-1 mol(-1) and compare to +/-0.5% with estimates from the ATHAS data bank using contributions of other polymers with the same constituent groups. The glass transition temperature of the completely amorphous polymer is estimated to be 310-315 K with a Delta C-p of about 94 J K-1 mol(-1). Knowing C-p of the solid, liquid, and the transition parameters, the thermodynamic functions enthalpy, entropy, and Gibbs function were obtained. With these data one can compute for semicrystalline samples crystallinity changes with temperature, mobile amorphous fractions, and resolve the question of rigid-amorphous fractions. (C) 1998 John Wiley & Sons, Inc. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Shell Chem Co, Westhollow Technol Ctr, Houston, TX 77251 USA. Univ Nizhnii Novgorod, Inst Chem, Nizhnii Novgorod 603600, Russia. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 40 TC 191 Z9 194 U1 2 U2 30 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD OCT PY 1998 VL 36 IS 14 BP 2499 EP 2511 DI 10.1002/(SICI)1099-0488(199810)36:14<2499::AID-POLB4>3.0.CO;2-O PG 13 WC Polymer Science SC Polymer Science GA 123FT UT WOS:000076115700004 ER PT J AU Laurer, JH Mulling, JF Khan, SA Spontak, RJ Lin, JS Bukovnik, R AF Laurer, JH Mulling, JF Khan, SA Spontak, RJ Lin, JS Bukovnik, R TI Thermoplastic elastomer gels. II. Effects of composition and temperature on morphology and gel rheology SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE block copolymer; thermoplastic elastomer; physical gel; order-disorder transition ID COPOLYMER HOMOPOLYMER BLENDS; ANGLE X-RAY; TRIBLOCK COPOLYMER; BLOCK-COPOLYMER; NEUTRON-SCATTERING; DIBLOCK COPOLYMER; PHYSICAL GELATION; MOLECULAR-WEIGHT; BINARY BLENDS; SHEAR AB Thermoplastic elastomer gels (TPEGs) composed of a poly[styrene-b-(ethylene-co-butylene)-b-styrene] triblock copolymer and a low-volatility, midblock-compatible mineral oil have been investigated here to ascertain the effects of composition on TPEG morphology, and temperature on mechanical properties. Cryofracture-replication transmission electron micrographs reveal the existence of spheroidal bumps due to copolymer micelles, as well as a network of irregularly shaped, high-aspect-ratio features. Since the density of this network decreases with increasing oil concentration, these features are attributed to copolymer grain boundaries. Micellar periodicities are discerned from small-angle X-ray scattering as a function of copolymer concentration and compared with previously reported data from related systems. Dynamic rheological tests performed up to 140 degrees C indicate that the linear viscoelastic regime for these TPEGs decreases with both increasing copolymer concentration and temperature. A concentration-dependent thermal transition, signified by an abrupt reduction in the dynamic elastic modulus (G'), has also been identified. (C) 1998 John Wiley & Sons, Inc. C1 N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. N Carolina State Univ, Dept Chem Engn, Raleigh, NC 27695 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Raychem Corp, Telecom & Elect Prod Div, Fuquay Varina, NC 27526 USA. RP Spontak, RJ (reprint author), N Carolina State Univ, Dept Mat Sci & Engn, Box 7907, Raleigh, NC 27695 USA. NR 44 TC 51 Z9 51 U1 3 U2 12 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD OCT PY 1998 VL 36 IS 14 BP 2513 EP 2523 PG 11 WC Polymer Science SC Polymer Science GA 123FT UT WOS:000076115700005 ER PT J AU Bruch, R Safronova, UI Shlyaptseva, AS Nilsen, J Schneider, D AF Bruch, R Safronova, UI Shlyaptseva, AS Nilsen, J Schneider, D TI New comprehensive theoretical analysis of the doubly excited 3lnl ' states of sodium-like iron SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID DOUBLE-ELECTRON CAPTURE; NA-LIKE IONS; SATELLITE SPECTRA; COLLISIONS; AUGER AB Energy levels, radiative transition probabilities and autoionization rates for Fe XVI including the 1s(2)2s(2)2p(5)3lnl' (n = 3-8, l' less than or equal to (n - 1)) and 1s(2)2s2p(6)3lnl' (n = 3-4, l' less than or equal to (n - 1)) doubly excited states were calculated by using the multi-configurational Hartree-Fock (Cowan code) method. The contribution of relativistic effects is studied in comparison with the data obtained using the multi-configurational Dirac-Fock (YODA code) method. The comparison of the theoretical data with experimental spectra obtained by double-electron capture in slow ion-atom collisions is discussed. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Nevada, Dept Phys, Reno, NV 89557 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Russian Acad Sci, Inst Spect, Troitsk 142092, Russia. RP Bruch, R (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. NR 12 TC 3 Z9 3 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD OCT PY 1998 VL 60 IS 4 BP 605 EP 622 DI 10.1016/S0022-4073(97)00228-8 PG 18 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 114DP UT WOS:000075594100011 ER PT J AU Martin, RC Byrne, TE Miller, LF AF Martin, RC Byrne, TE Miller, LF TI Biomedical neutron research at The Californium User Facility for Neutron Science SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 4th International Conference on Methods and Applications of Radioanalytical Chemistry CY APR 06-11, 1997 CL KAILUA KONA, HI SP Amer Nucl Soc, Isotopes & Radiat Div, Amer Nucl Soc, Biol & Med Div, Canadian Nucl Soc, Amer Chem Soc, Div Nucl Chem & Technol AB The Californium User Facility for Neutron Science has been established at Oak Ridge National Laboratory (ORNL). The Californium User Facility (CUF) is a part of the larger Californium Facility, which fabricates and stores compact (252)Cf neutron sources for worldwide distribution. The CUF can provide a cost-effective option for research with 252Cf sources. Three projects at the CUF that demonstrate the versatility of (252)Cf for biological and biomedical neutron-based research are described: future establishment of a (252)Cf-based neutron activation analysis system, ongoing work to produce miniature high-intensity, remotely afterloaded (252)Cf sources for tumor therapy, and a recent experiment that irradiated living human lung cancer cells impregnated with experimental boron compounds to test their effectiveness for boron neutron capture therapy. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Roane State Community Coll, Dept Biol, Harriman, TN 37748 USA. Univ Tennessee, Dept Nucl Engn, Knoxville, TN 37996 USA. RP Martin, RC (reprint author), Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. EM Martinrc@ornl.gov NR 8 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD OCT PY 1998 VL 236 IS 1-2 BP 5 EP 10 DI 10.1007/BF02386308 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 131KD UT WOS:000076574100001 ER PT J AU Klunder, GL Andrews, JE Church, MN Spear, JD Russo, RE Grant, PM Andresen, BD AF Klunder, GL Andrews, JE Church, MN Spear, JD Russo, RE Grant, PM Andresen, BD TI Nuclear fission product analysis using capillary separation techniques SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 4th International Conference on Methods and Applications of Radioanalytical Chemistry CY APR 06-11, 1997 CL KAILUA KONA, HAWAII SP Amer Nucl Soc, Isotopes & Radiat Div, Amer Nucl Soc, Biol & Med Div, Canadian Nucl Soc, Amer Chem Soc, Div Nucl Chem & Technol ID ISOTACHOPHORESIS-ZONE ELECTROPHORESIS; COMPLEX-FORMING EQUILIBRIA; METAL-IONS; 8-HYDROXYQUINOLINE-5-SULFONIC ACID; STABILITY-CONSTANTS; DETECTOR; SIMULATION AB Capillary electrophoresis has been used to separate metal ions characteristically associated with nuclear fission. Electrokinetic injections and transient isotachophoretic techniques were employed to increase sample loading and provide on-column concentration of the analyte. On-line concentration factors of approximately 700-fold have been achieved. Indirect-UV absorbance, on-line radioactivity, and indirect laser-induced fluorescence detection were used to monitor analytes of interest. The radioactivity detector consists of a plastic scintillator and photomultiplier tube with a 4 pi detection geometry. The efficiency was determined to be approximately 80%, enabling samples resident in the detector window for 0.1 minutes to be reliably assayed. Detection of Eu-152 and Cs-137 was achieved at the low nCi level. Indirect fluorescence was performed with quinine sulfate as the background fluorophor with alpha-hydroxyisobutyric acid added as a complexing agent. An argon ion laser was used as the excitation source with a diode array detector. Limits of detection for La3+, Ce3+, Pr3+, Nd3+, Sm3+, and Eu3+ were determined to be in the sub - 10 ppb range (6-11 nM) with indirect laser-induced fluorescence detection. C1 Univ Calif Lawrence Livermore Natl Lab, Forens Sci Ctr, Livermore, CA 94551 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Klunder, GL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Forens Sci Ctr, POB 808,L-178, Livermore, CA 94551 USA. NR 23 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD OCT PY 1998 VL 236 IS 1-2 BP 149 EP 153 DI 10.1007/BF02386333 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 131KD UT WOS:000076574100026 ER PT J AU Taylor, WA Garcia, JG Hamilton, VT Heaton, RC Jamriska, DJ Ott, MA Phillips, DR Radzinski, SD AF Taylor, WA Garcia, JG Hamilton, VT Heaton, RC Jamriska, DJ Ott, MA Phillips, DR Radzinski, SD TI Recovery of hafnium radioisotopes from a proton irradiated tantalum target SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 4th International Conference on Methods and Applications of Radioanalytical Chemistry CY APR 06-11, 1997 CL KAILUA KONA, HAWAII SP Amer Nucl Soc, Isotopes & Radiat Div, Amer Nucl Soc, Biol & Med Div, Canadian Nucl Soc, Amer Chem Soc, Div Nucl Chem & Technol AB The Hf-178m2 nucleus, with its long half-life (31 y) and high-spin isomeric state (16(+)) is desired for new and exotic nuclear physics studies. The Los Alamos Radioisotope Program irradiated a kilogram of natural tantalum at the Los Alamos Meson Physics Facility in early 1981. After fifteen years of decay, this target was ideal for the recovery of Hf-178m2. There was more than a millicurie of Hf-178m2 produced during this irradiation and there has been a sufficient period of time for most of the other hafnium radioisotopes to decayed away. Traditionally, separation techniques for recovering hafnium isotopes from tantalum targets employ solvent extractions with reagents that are considered hazardous. These techniques are no longer condoned because they generate a mixed-waste (radioactive and hazardous components) that can not be treated for disposal. In this paper we describe a new and unique procedure for the recovery of hafnium radioisotopes from a highly radioactive, proton irradiated, tantalum target using reagents that do not contribute a hazardous waste component. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Taylor, WA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Garcia, Joe/E-8862-2010 NR 11 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD OCT PY 1998 VL 236 IS 1-2 BP 155 EP 157 DI 10.1007/BF02386334 PG 3 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 131KD UT WOS:000076574100027 ER PT J AU Talley, DG Bourcier, SC McDonald, MJ Longley, SW Parma, EJ AF Talley, DG Bourcier, SC McDonald, MJ Longley, SW Parma, EJ TI Initial generation and separation of Mo-99 at Sandia National Laboratories SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 4th International Conference on Methods and Applications of Radioanalytical Chemistry CY APR 06-11, 1997 CL KAILUA KONA, HAWAII SP Amer Nucl Soc, Isotopes & Radiat Div, Amer Nucl Soc, Biol & Med Div, Canadian Nucl Soc, Amer Chem Soc, Div Nucl Chem & Technol AB The radioisotope Tc-99m, used in greater than 80% of nuclear medicine applications, has traditionally been produced and supplied to radiopharmaceutical companies in the form of its precursor Mo-99. Nuclear fission produced 99Mo had been supplied by Nordion International of Canada and Cintichem, Inc. of New York, USA. With the shutdown of Cintichem's reactor in 1989, a need was recognized for a US supply, and the US Department of Energy recently published a record of decision designating Sandia National Laboratories (SNL) to meet that need. A recent campaign was launched which utilized the SNL Annular Core Research Reactor to irradiate UO2 coated targets fabricated by Los Alamos National Laboratory to produce 99Mo. The irradiated targets were chemically processed in the SNL Hot Cell Facility to separate and purify the Mo-99. The campaign also included final product quality analysis, and process waste handling. The campaign was accomplished with high Mo-99 recovery. Final product quality was assessed at SNL, and samples were sent to an outside laboratory for independent verification. The campaign provided data and experience useful in pursuing US Food and Drug Administration and radiopharmaceutical company approval. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Talley, DG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 3 Z9 3 U1 3 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD OCT PY 1998 VL 236 IS 1-2 BP 169 EP 173 DI 10.1007/BF02386337 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 131KD UT WOS:000076574100030 ER PT J AU Beals, DM Britt, WG Bibler, JP Brooks, DA AF Beals, DM Britt, WG Bibler, JP Brooks, DA TI Radionuclide analysis using solid phase extraction disks SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 4th International Conference on Methods and Applications of Radioanalytical Chemistry CY APR 06-11, 1997 CL KAILUA KONA, HAWAII SP Amer Nucl Soc, Isotopes & Radiat Div, Amer Nucl Soc, Biol & Med Div, Canadian Nucl Soc, Amer Chem Soc, Div Nucl Chem & Technol ID SAMPLES AB The use of solid phase extraction (SPE) disks was studied for the quantification of selected radionuclides in aqueous solutions. The extraction of four radionuclides using six types (two commercial, four test materials) of 3M Empore(TM) RAD disks was studied. The radionuclides studied were: technetium-99 (two types of disks), cesium-137 (two types), strontium-90 (one type), plutonium-238 (one type). Extractions were tested from DI water, liver water and seawater. Extraction efficiency, kinetics (flow rate past the disk), capacity, and potential interferences were studied as well as quantification methods. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Beals, DM (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 7 TC 13 Z9 16 U1 1 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD OCT PY 1998 VL 236 IS 1-2 BP 187 EP 191 DI 10.1007/BF02386340 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 131KD UT WOS:000076574100033 ER PT J AU Dale, D Brooks, G Monagle, M AF Dale, D Brooks, G Monagle, M TI Comparison of ultrasonic assisted digestion with traditional methods for alpha/beta analysis SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 4th International Conference on Methods and Applications of Radioanalytical Chemistry CY APR 06-11, 1997 CL KAILUA KONA, HAWAII SP Amer Nucl Soc, Isotopes & Radiat Div, Amer Nucl Soc, Biol & Med Div, Canadian Nucl Soc, Amer Chem Soc, Div Nucl Chem & Technol AB An ever-increasing priority of many customers in the radiochemistry field is the turn-around time of sample analysis. While modem instrumentation provides acceptable detection limits with relatively short count times, the sample preparation step remains the time-consuming step in radiochemical analysis. We have developed fast sample preparation techniques for gross alpha/beta analysis based on ultrasonically assisted digestion as part of a mobile radiological analytical laboratory program in place at Los Alamos National Laboratory (LANL). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dale, D (reprint author), Univ Calif Los Alamos Natl Lab, MS K484, Los Alamos, NM 87545 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD OCT PY 1998 VL 236 IS 1-2 BP 199 EP 203 DI 10.1007/BF02386342 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 131KD UT WOS:000076574100035 ER PT J AU Espinosa, G Gammage, RB AF Espinosa, G Gammage, RB TI Indoor radon concentration survey in Mexico SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 4th International Conference on Methods and Applications of Radioanalytical Chemistry CY APR 06-11, 1997 CL KAILUA KONA, HAWAII SP Amer Nucl Soc, Isotopes & Radiat Div, Amer Nucl Soc, Biol & Med Div, Canadian Nucl Soc, Amer Chem Soc, Div Nucl Chem & Technol AB Indoor radon evaluations in specific regions of the country have been performed in an effort to assess the magnitude of the radon problem and its public health consequences. The survey of this paper covers four large non-tropical regions of north and central Mexico, and reports the results of measurements of indoor radon concentrations in houses of towns with between 100,001 and 500,000 inhabitants. The measurements were done by using passive detectors. namely, the closed-end-cup system with CR-39 polycarbonate chips as detector material. The measurements were performed throughout the two coldest seasons (between 5 and 20 degrees C), winter and spring, in integration periods of 28 days covering the six month cycle. The results show a moderate average radon concentration below 200 Bq.m(-3) with occasional higher values. This is very probably due to the climate conditions and the traditional habits of open door and window ventilation. The IFUNAM (Instituto de Fisica, Universidad Nacional Autonoma de Mexico) Laboratory, where the closed-end cup system for radon was developed, has gained experience though this survey and is willing to share it for future surveys at regional or national levels. C1 Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 01000, DF, Mexico. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Espinosa, G (reprint author), Univ Nacl Autonoma Mexico, Inst Fis, Apdo Postal 20-364, Mexico City 01000, DF, Mexico. NR 6 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD OCT PY 1998 VL 236 IS 1-2 BP 227 EP 229 DI 10.1007/BF02386347 PG 3 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 131KD UT WOS:000076574100040 ER PT J AU Corbett, DR Burnett, WC Cable, PH Clark, SB AF Corbett, DR Burnett, WC Cable, PH Clark, SB TI A multiple approach to the determination of radon fluxes from sediments SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 4th International Conference on Methods and Applications of Radioanalytical Chemistry CY APR 06-11, 1997 CL KAILUA KONA, HAWAII SP Amer Nucl Soc, Isotopes & Radiat Div, Amer Nucl Soc, Biol & Med Div, Canadian Nucl Soc, Amer Chem Soc, Div Nucl Chem & Technol ID GAS-EXCHANGE RATES; GROUNDWATER DISCHARGE; MARINE-SEDIMENTS; RN-222; WATER; TRANSPORT; AIR AB Determination of sedimentary fluxes of Rn-222 via diffusion was required as an input for a mass balance model of radon in a freshwater lake. We obtained these fluxes by: (1) direct measurement in the laboratory using a simulated sediment bed and water column; (2) a "sediment equilibration" technique; and (3) porewater modeling. The first method, analogous to an in situ benthic chamber approach, uses direct observation of the increasing Rn-222 activity in water overlying a sediment bed packed in plastic columns. This allows one to directly measure the fluxes and determine the effective wet bulk sediment diffusion coefficient (D-s). Radon flux estimates using these three techniques agreed to within approximately 10-15%. C1 Florida State Univ, Dept Oceanog, Environm Radioact Measurement Facil, Tallahassee, FL 32306 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Corbett, DR (reprint author), Florida State Univ, Dept Oceanog, Environm Radioact Measurement Facil, Tallahassee, FL 32306 USA. NR 16 TC 57 Z9 59 U1 3 U2 25 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD OCT PY 1998 VL 236 IS 1-2 BP 247 EP 252 DI 10.1007/BF02386351 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 131KD UT WOS:000076574100044 ER PT J AU Lemke, C Dreybrodt, W Shelnutt, JA Quirke, JME Schweitzer-Stenner, R AF Lemke, C Dreybrodt, W Shelnutt, JA Quirke, JME Schweitzer-Stenner, R TI Polarized Raman dispersion spectroscopy probes planar and non-planar distortions of Ni(II) porphyrins with different peripheral substituents SO JOURNAL OF RAMAN SPECTROSCOPY LA English DT Article ID DEPOLARIZATION RATIO DISPERSION; EXCITATION PROFILES; CONFORMATIONAL PROPERTIES; FERROCYTOCHROME-C; HEME; FUNDAMENTALS; OCTAETHYLPORPHYRIN; SYMMETRY; REVEALS AB Porphyrins exhibiting ideal D-4h symmetry show depolarization ratios of their Raman-active A(1g), B-1g, B-2g and A(2g) type vibrations which are independent of the wavenumber of the exciting radiation, namely 0.125 for A(1g), 0.75 for B-1g and B-2g and infinite for A(2g) modes. Symmetry-lowering distortions, which can be classified in terms of the irreducible representations of the D-4h point group and expressed as linear combinations of normal coordinate deformations, i.e. static displacements along the normal modes, mix Raman tensors of different symmetry. This can cause a dispersion of the depolarization ratios with respect to the excitation wavenumber. By expanding the vibronic coupling operator in the quantum mechanical expression of the Raman tensor to second order with respect to the normal coordinate deformations, one can show hy group theoretical arguments that the dispersion of the depolarization ratio can be induced by in-plane A(1g), B-1g, B-2g and A(2g) or by at least two E-u or out-of-plane A(1u), A(2u), B-1u and B-2u distortions. This is illustrated by experimentally determined Raman excitation profiles obtained from the polarized spectra of Ni(II)-octaethylporphyrin, the meso-carbons of which are substituted by NO2 at position 5 (C-2v) or the positions 5 and 15 (D-2h). In both cases symmetry-lowering distortions of B-2g symmetry are induced. The depolarization ratio dispersion, however, reflects additional out-of-plane distortions of B-1u (ruffling) and B-2u (saddling) symmetry. These data are compared with depolarization ratios observed for Raman lines of the planar Ni(II)-porphin (D-4h) and the non-planar Ni(II)-octaethyltetraphenylporphyrin. The latter exhibits S-4 symmetry reflected by a strong depolarization ratio dispersion of A(1g) and A(2g) type modes. Finally, a theoretical approach is discussed which formulates the Raman tensor in terms of vibronic coupling parameters depending on the symmetry classified normal coordinate deformations. These parameters are determined by simultaneous fits to the depolarization ratio dispersion data and the corresponding resonance excitation profiles. Hence the applicability of polarized Raman dispersion spectroscopy to identify symmetry-lowering distortions induced by peripheral substituents, and in proteins, by specific heme-protein interactions is demonstrated. (C) 1998 John Wiley & Sons, Ltd. C1 Univ Bremen, FBI, Inst Expt Phys, D-28359 Bremen, Germany. Sandia Natl Labs, Mat Theory & Computat Dept, Albuquerque, NM 87815 USA. Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. Florida Int Univ, Dept Chem, Miami, FL 33199 USA. RP Dreybrodt, W (reprint author), Univ Bremen, FBI, Inst Expt Phys, D-28359 Bremen, Germany. EM dreybrod@physik.uni-bremen.de; stenner@theo.physik.uni-bremen.de RI Shelnutt, John/A-9987-2009 OI Shelnutt, John/0000-0001-7368-582X NR 23 TC 22 Z9 22 U1 0 U2 5 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0377-0486 J9 J RAMAN SPECTROSC JI J. Raman Spectrosc. PD OCT-NOV PY 1998 VL 29 IS 10-11 BP 945 EP 953 DI 10.1002/(SICI)1097-4555(199810/11)29:10/11<945::AID-JRS321>3.3.CO;2-W PG 9 WC Spectroscopy SC Spectroscopy GA 141DH UT WOS:000077127000012 ER PT J AU Shao-Horn, Y Hackney, SA Johnson, CS Kahaian, AJ Thackeray, MM AF Shao-Horn, Y Hackney, SA Johnson, CS Kahaian, AJ Thackeray, MM TI Structural features of low-temperature LiCoO2 and acid-delithiated products SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID NEUTRON-DIFFRACTION; LITHIUM; OXIDE; ELECTROCHEMISTRY; 400-DEGREES-C; SPINEL AB X-ray diffraction and transmission electron microscopy were used to study the structural features of low-temperature LiCoO2, (LT-LiCoO2) samples prepared at 400 degrees C either by a simple solid-state reaction or via a sol-gel process. Single-crystal electron diffraction analysis showed that both a lithiated-spinel Li, [Co-2]O-4 (Fd3m) and a layered-type structure (R (3) over bar m) were present in LT-LiCoO2, samples hut that the lithiated-spinel structure was the major phase. Electron diffraction analysis also indicated that some crystallites in the LT-LiCoO2, samples had a cation distribution in the spinel notation, {(Li16-4x)(16c)[Li-4x](16d)}(layer1) {(Co16-4x)(16d)[Co-4x](16c)}(layer2)O-32 (0 < x < 1) that was intermediate between the ideal layered (x = 1) and ideal lithiated-spinel (x = 0) structures. Electron diffraction confirmed that acid-delithiation of LT-LiCoO2, resulted in a lithium-deficient spinel, Li-0.8[Co-2]O-4, with lithium ions on the tetrahedral sites of the spinel structure. The structural features of LT-LiCoO2, and the acid-delithiated Li0.4CoO2 products provide reasons for the poor electrochemical properties of Li/LT-LiCoO2, cells and are consistent with earlier studies. (C) 1998 Academic Press. C1 Michigan Technol Univ, Dept Met & Mat Engn, Houghton, MI 49931 USA. Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, Argonne, IL 60439 USA. RP Hackney, SA (reprint author), Michigan Technol Univ, Dept Met & Mat Engn, Houghton, MI 49931 USA. EM Hackney@mtu.edu NR 16 TC 37 Z9 39 U1 2 U2 29 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 OCT PY 1998 VL 140 IS 1 BP 116 EP 127 DI 10.1006/jssc.1998.7873 PG 12 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 128CG UT WOS:000076387200015 ER PT J AU Aluru, S Gustafson, J Prabhu, GM Sevilgen, FE AF Aluru, S Gustafson, J Prabhu, GM Sevilgen, FE TI Distribution-independent hierarchical algorithms for the N-body problem SO JOURNAL OF SUPERCOMPUTING LA English DT Article DE Barnes-Hut algorithm; Greengard's algorithm; N-body problem; particle simulation; quadtree ID VECTORIZATION; SIMULATION AB The N-body problem is to simulate the motion of N particles under the influence of mutual force fields based on an inverse square law. Greengard's algorithm claims to compute the cumulative force on each particle in O(N) time for a fixed precision irrespective of the distribution of the particles. In this paper, we show that Greengard's algorithm is distribution dependent and has a lower bound of Omega(N log(2) N) in two dimensions and Omega(N log(4) N) in three dimensions. We analyze the Greengard and Barnes-Hut algorithms and show that they are unbounded for arbitrary distributions. We also present a truly distribution independent algorithm for the N-body problem that runs in O(N log N) time for any fixed dimension. C1 New Mexico State Univ, Dept CS, Las Cruces, NM 88003 USA. Iowa State Univ, Ames Lab, Scalable Comp Lab, Ames, IA 50011 USA. Iowa State Univ, Dept CS, Ames, IA 50011 USA. Syracuse Univ, Dept EECS, Syracuse, NY 13244 USA. RP New Mexico State Univ, Dept CS, Las Cruces, NM 88003 USA. EM aluru@cs.nmsu.edu; gus@scl.ameslab.gov; prabhu@cs.iastate.edu; sevilgen@top.cis.syr.edu NR 24 TC 9 Z9 9 U1 1 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0920-8542 EI 1573-0484 J9 J SUPERCOMPUT JI J. Supercomput. PD OCT PY 1998 VL 12 IS 4 BP 303 EP 323 DI 10.1023/A:1008047806690 PG 21 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 136BH UT WOS:000076837500001 ER PT J AU Goyal, A List, FA Mathis, J Paranthaman, M Specht, ED Norton, DP Park, C Lee, DF Kroeger, DM Christen, DK Budai, JD Martin, PM AF Goyal, A List, FA Mathis, J Paranthaman, M Specht, ED Norton, DP Park, C Lee, DF Kroeger, DM Christen, DK Budai, JD Martin, PM TI High critical current density YBa2Cu3Ox tapes using the RABiTs approach SO JOURNAL OF SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT TMS Superconductivity Session CY FEB, 1998 CL SAN ANTONIO, TEXAS DE YBa2Cu3Ox; tapes; RABiTS; high critical current density ID SUPERCONDUCTING TAPES; NI TAPES; FILMS; DEPOSITION AB Progress in the fabrication of epitaxial, high-J(c), biaxially aligned YBCO thick films on Rolling-assisted biaxially textured substrates (RABiTs) is reported. RABiT substrates comprise a biaxially textured metal substrate with epitaxial oxide buffer layers suitable for growth of superconductors. Oxide buffer layers have been deposited using three techniques: laser ablation, electron-beam evaporation, and sputtering. Epitaxial YBCO films grown using laser ablation on such substrates have critical current densities approaching 3 x 10(6) A/cm(2) at 77 K in zero field and have field dependences similar to epitaxial films on single crystal ceramic substrates. Critical current densities in excess of 0.2 MA/cm(2) have been obtained on stronger, nonmagnetic substrates. In addition, samples with J(e) of 12.5 kA/cm(2) at 77 K have been fabricated. The highest strain tolerence obtained so far is 0.7% in compression and 0.25% in tension. Deposited conductors made using this technique offer a potential route for the fabrication of long lengths of high-J(c) wire capable of carrying high currents in high magnetic fields and at elevated temperatures. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Goyal, A (reprint author), Oak Ridge Natl Lab, POB 2008,MS 6116, Oak Ridge, TN 37831 USA. RI Yoon, Sejin/F-7637-2013; Specht, Eliot/A-5654-2009; Paranthaman, Mariappan/N-3866-2015; Budai, John/R-9276-2016 OI Specht, Eliot/0000-0002-3191-2163; Paranthaman, Mariappan/0000-0003-3009-8531; Budai, John/0000-0002-7444-1306 NR 13 TC 40 Z9 40 U1 1 U2 3 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0896-1107 J9 J SUPERCOND JI J. Supercond. PD OCT PY 1998 VL 11 IS 5 BP 481 EP 487 DI 10.1023/A:1022658506926 PG 7 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 139ZZ UT WOS:000077062200001 ER PT J AU Athur, SP Putman, P Balachandran, U Salama, K AF Athur, SP Putman, P Balachandran, U Salama, K TI Phase formation and melt processing of Yb-123 SO JOURNAL OF SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT TMS Superconductivity Session CY FEB, 1998 CL SAN ANTONIO, TEXAS DE Yb-123; melt processing; phase formation; reduced oxygen partial pressure ID SUPERCONDUCTOR; GROWTH; YBBA2CU3O7-X; YBA2CU3O7-X; OXYGEN AB The formation of Yb-123 has been studied at different temperatures in air and in reduced oxygen partial pressure. It is found that the stability and/or the formation kinetics of Yb-123 phase is a major hurdle in manufacturing phase-pure Yb-123 in air. However, under reduced oxygen partial pressure, Yb-123 forms rapidly and more than 90% phase-pure Yb-123 is achieved within three sintering steps. Rods made from this powder were melt-processed in air and showed a T-c of 90 K. Kinetic studies performed by interrupting the growth during the directional solidification of these rods revealed a growth mechanism similar to that of Y-123 and a maximum growth rate of 7.2 mm/h for a stable planar interface. EPMA of the interface showed the liquid to be rich in barium cuprates with a Ba:Cu ratio of 1.3. C1 Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Univ Houston, Dept Engn Mech, Houston, TX 77204 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60349 USA. RP Athur, SP (reprint author), Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. NR 14 TC 9 Z9 9 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0896-1107 J9 J SUPERCOND JI J. Supercond. PD OCT PY 1998 VL 11 IS 5 BP 525 EP 531 DI 10.1023/A:1022670809652 PG 7 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 139ZZ UT WOS:000077062200007 ER PT J AU Iyer, AN Salib, S Mironova, M Vipulanandan, C Balachandran, U Salama, K AF Iyer, AN Salib, S Mironova, M Vipulanandan, C Balachandran, U Salama, K TI Fabrication and electromechanical characterization of silver-clad BSCCO tapes SO JOURNAL OF SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT TMS Superconductivity Session CY FEB, 1998 CL SAN ANTONIO, TX DE groove rolling powder-in-tube technique; BSCCO; current transport properties; phase development; in situ tensile test; strain tolerance ID CRITICAL-CURRENT-DENSITY; SUPERCONDUCTING TAPES; GRAIN-BOUNDARIES; TRANSPORT CURRENT; SHEATHED TAPES; TEMPERATURE; MICROSTRUCTURE; STRAIN; MODEL; WIRES AB The powder-in-tube technique consisting of industrial processes such as wire drawing and rolling has been widely used to fabricate superconducting tapes. In the present investigation a novel technique was adopted to fabricate BSCCO 2223 tapes. Instead of wire drawing, the silver billet was reduced in size by groove rolling. Stress conditions during groove rolling were analyzed and appropriate changes were incorporated to optimize the deformation process. Subsequent thermomechanical treatment resulted in tapes with average critical current densities of 18,000 A/cm(2). Phase development and microstructural evolution during the thermomechanical treatment were studied using XRD, SEM, and TEM. The electromechanical properties of monofilament and composite BSCCO tapes were evaluated by subjecting them to in situ tensile tests. The strain tolerance of the composite was found to be better than that of the monofilament BSCCO tape. C1 Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. NR 27 TC 4 Z9 4 U1 0 U2 3 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0896-1107 J9 J SUPERCOND JI J. Supercond. PD OCT PY 1998 VL 11 IS 5 BP 533 EP 543 DI 10.1023/A:1022623026490 PG 11 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 139ZZ UT WOS:000077062200008 ER PT J AU Yonker, CR Linehan, JC Fulton, JL AF Yonker, CR Linehan, JC Fulton, JL TI The use of high pressure NMR for the determination of phase behavior for select binary solvent systems SO JOURNAL OF SUPERCRITICAL FLUIDS LA English DT Article DE binary supercritical fluids; high pressure NMR; vapor-liquid equilibrium ID SUPERCRITICAL FLUIDS; CARBON-DIOXIDE; TEMPERATURE; EQUILIBRIA; METHANOL; APPARATUS; MIXTURES; ALCOHOL AB High pressure NMR has proven itself to be a valuable technique for the study of supercritical fluid solutions. In this manuscript, we describe the extension of high pressure NMR to the investigation of the phase behavior for two binary solvent systems; ethylene-methanol and propane-methanol. The phase behavior was investigated as a function of pressure and temperature, with the molar composition of both phases being determined simultaneously, in situ, in a high pressure capillary NMR cell. The hydrogen bonding behavior of the alcohol in both phases determined in these experiments, provides important physicochemical information regarding solvent interactions occurring in both the liquid and vapor phase. High pressure NMR proves to be an efficient method for obtaining vapor liquid equilibrium data and critical conditions of binary solvent systems. This methodology should also be applicable to ternary systems as well as to more extreme solvent systems, such as, supercritical water. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Div Environm & Hlth Sci, Richland, WA 99352 USA. RP Yonker, CR (reprint author), Pacific NW Lab, Div Environm & Hlth Sci, POB 999, Richland, WA 99352 USA. EM Clem.Yonker@pnl.gov NR 17 TC 11 Z9 11 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0896-8446 J9 J SUPERCRIT FLUID JI J. Supercrit. Fluids PD OCT 1 PY 1998 VL 14 IS 1 BP 9 EP 16 DI 10.1016/S0896-8446(98)00098-9 PG 8 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 141KH UT WOS:000077142600002 ER PT J AU Hoffmann, MM Conradi, MS AF Hoffmann, MM Conradi, MS TI Hydrogen exchange reactions in supercritical media monitored by in situ NMR SO JOURNAL OF SUPERCRITICAL FLUIDS LA English DT Article DE deuteration reactions; high temperature high pressure NMR spectroscopy; hydrogen exchange; supercritical alcohols; supercritical water ID WATER; LIQUIDS AB Well established, simple NMR techniques are applied to the in situ study of hydrogen exchange reactions in supercritical aqueous solutions and the supercritical alcohols methanol and ethanol. In the case of the rapidly exchanging hydroxyl protons of alcohols and water, changes in the exchange rate are evidenced by the collapse of chemical shift differences (in solutions) and the collapse of J-multiplets. We show that the hydrogen exchange rate can be adjusted by changing pressure (density) at a constant supercritical temperature. Higher pressure at constant temperature increases the exchange rate, indicating that hydrogen exchange at supercritical conditions proceeds via charged intermediates. The pure alcohols at temperatures above 200 degrees C exhibit exchange of hydroxyl protons at a rate of 5 s(-1) already at low, gas-like densities. However, the hydrogen exchange rate in the pure and aqueous alcohols is found to be very sensitive to the presence of impurities. The much slower deuteration of aliphatic and aromatic protons in 4-ethylphenol by supercritical D2O was monitored in situ from the time dependence of the resonance intensities. Suitable pressure-temperature conditions are identified for the purpose of selective deuteration of 4-ethylphenol. The corresponding reaction rates are reported. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Washington Univ, Dept Chem & Phys, St Louis, MO 63130 USA. RP Hoffmann, MM (reprint author), Pacific NW Lab, Battelle Blvd,POB 999,MS P8-19, Richland, WA 99352 USA. EM Markus.Hoffmann@pnl.gov NR 27 TC 18 Z9 18 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0896-8446 J9 J SUPERCRIT FLUID JI J. Supercrit. Fluids PD OCT 1 PY 1998 VL 14 IS 1 BP 31 EP 40 DI 10.1016/S0896-8446(98)00094-1 PG 10 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 141KH UT WOS:000077142600004 ER PT J AU Morrison, GC Nazaroff, WW Cano-Ruiz, JA Hodgson, AT Modera, MP AF Morrison, GC Nazaroff, WW Cano-Ruiz, JA Hodgson, AT Modera, MP TI Indoor air quality impacts of ventilation ducts: Ozone removal and emissions of volatile organic compounds SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID CHEMISTRY; DEPOSITION; EXPOSURES; SURFACES; RATES; HEAT AB The concentrations of contaminants in the supply air of mechanically ventilated buildings may be altered by pollutant emissions from and interactions with duct materials. We measured the emission rate of volatile organic compounds (VOCs) and aldehydes from materials typically found in ventilation ducts. The emission rate of VOCs per exposed surface area of materials was found to be low for some duct liners, but high for duct sealing caulk and a neoprene gasket. For a typical duct, the contribution to VOC concentrations is predicted to be only a few percent of common indoor levels. We exposed selected materials to similar to 100-ppb ozone and measured VOC emissions. Exposure to ozone increased the emission rates of aldehydes from a duct liner, duct sealing caulk, and neoprene gasket. The emission of aldehydes from these materials could increase indoor air concentrations by amounts that are as much as 20% of odor thresholds. We also measured the rate of ozone uptake on duct liners and galvanized sheet metal to predict how much ozone might be removed by a typical duct in ventilation systems. For exposure to a constant ozone mol fraction of 37 ppb, a lined duct would initially remove similar to 9% of the ozone, but over a period of 10 days the ozone removal efficiency would diminish to less than 4%. In an unlined duct, in which only galvanized sheet metal is exposed to the airstream, the removal efficiency would be much lower, similar to 0.02%. Therefore, ducts in ventilation systems are unlikely to be a major sink for ozone. C1 Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. MIT, Dept Chem Engn, Cambridge, MA 02139 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Nazaroff, WW (reprint author), Univ Calif Berkeley, Dept Civil & Environm Engn, 633 Davis Hall, Berkeley, CA 94720 USA. RI Nazaroff, William/C-4106-2008; Morrison, Glenn/B-4261-2016 OI Nazaroff, William/0000-0001-5645-3357; Morrison, Glenn/0000-0001-6876-7185 NR 32 TC 46 Z9 46 U1 1 U2 10 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 OCT PY 1998 VL 48 IS 10 BP 941 EP 952 PG 12 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 164NG UT WOS:000078470000007 PM 9798434 ER PT J AU Van Loy, MD Nazaroff, WW Daisey, JM AF Van Loy, MD Nazaroff, WW Daisey, JM TI Nicotine as a marker for environmental tobacco smoke: Implications of sorption on indoor surface materials SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID CHEMICAL-COMPOSITION; PASSIVE SMOKING; HEART-DISEASE; UNITED-STATES; EXPOSURE; AIR; VENTILATION; DEPOSITION; PARTICLES; RISK AB Recently developed models and data describing the interactions of gas-phase semi-volatile organic compounds with indoor surfaces are employed to examine the effects of sorption on nicotine's suitability as an environmental tobacco smoke (ETS) marker. Using parameters from our studies of nicotine sorption on carpet, painted wallboard, and stainless steel and previously published data on ETS particle deposition, the dynamic behavior of nicotine was modeled in two different indoor environments: a house and a stainless steel chamber. The results show that apparently contradictory observations of nicotine's behavior in indoor air can be understood by considering the effects of sorption under different experimental conditions. In indoor environments in which smoking has occurred regularly for an extended period, the sorbed mass of nicotine is very large relative to the mass emitted by a single cigarette. The importance of nicotine adsorption relative to ventilation as a gas-phase removal mechanism is reduced. Where smoking occurs less regularly or the indoor surfaces are cleaned prior to smoking las in a laboratory chamber), nicotine deposition is more significant. Nicotine concentrations closely track the levels of other ETS constituents in environments with habitual smoking if the data are averaged over a period significantly longer than the period between cigarette combustion episodes. However, nicotine is not a suitable tracer for predicting ETS exposures at fine time scales or in settings where smoking occurs infrequently and irregularly. C1 Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. EO Lawrence Berkeley Natl Lab, Indoor Environm Program, Berkeley, CA USA. RP Nazaroff, WW (reprint author), Univ Calif Berkeley, Dept Civil & Environm Engn, 633 Davis Hall, Berkeley, CA 94720 USA. RI Nazaroff, William/C-4106-2008 OI Nazaroff, William/0000-0001-5645-3357 NR 39 TC 16 Z9 16 U1 1 U2 7 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 OCT PY 1998 VL 48 IS 10 BP 959 EP 968 PG 10 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 164NG UT WOS:000078470000009 PM 28067161 ER PT J AU Stevens, L Lanning, JA Anderson, LG Jacoby, WA Chornet, N AF Stevens, L Lanning, JA Anderson, LG Jacoby, WA Chornet, N TI Investigation of the photocatalytic oxidation of low-level carbonyl compounds SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID FORMALDEHYDE; AIR AB Though the bulk of research involving photocatalytic oxidation (PCO) of volatile organic compounds (VOCs) has involved the remediation of pollutants at high inlet concentrations, there has been some implication that PCO can be used to reduce exposure to low concentrations of VOCs and improve the quality of indoor air. The high conversion rates previously reported for PCO of VOCs in the parts-per-million (ppm) range may not, however, be applicable to concentrations in the parts-per-billion (ppb) range that are more typical of indoor air quality (IAQ) issues. This paper reports on an examination of the operational characteristics of four PCO reactor designs used for the oxidation of VOCs in the ppb concentration range. Reactor efficiency is examined for three low molecular weight carbonyl compounds commonly associated with IAQ issues: formaldehyde, acetaldehyde, and acetone. The measured response is the destruction of carbonyl reactants. Variables include flow stream velocity and reactor residence time. Oxidation of carbonyl compounds is also examined as a function of ultraviolet (UV) radiation intensity. PCO of the formaldehyde and acetone was nearly 100% for all reactor designs. To assist comparison of the reactor designs, oxidation efficiency of trichloroethylene (TCE) was evaluated at inlet concentration in the parts-per-million by volume (ppmv) range. C1 Univ Colorado, Dept Chem, Denver, CO 80217 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Colorado, Ctr Environm Sci, Denver, CO 80217 USA. RP Stevens, L (reprint author), Univ Colorado, Dept Chem, Campus Box 194,POB 173364, Denver, CO 80217 USA. EM jlanning@castle.cudenver.edu NR 15 TC 23 Z9 25 U1 0 U2 5 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 OCT PY 1998 VL 48 IS 10 BP 979 EP 984 PG 6 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 164NG UT WOS:000078470000011 PM 28067155 ER PT J AU Fahrenholtz, WG Ewsuk, KG Loehman, RE AF Fahrenholtz, WG Ewsuk, KG Loehman, RE TI Kinetics of ceramic-metal composite formation by reactive metal penetration SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID ALUMINA ALUMINUM COMPOSITES; DIRECTED OXIDATION; MOLTEN ALUMINUM; GROWTH-KINETICS; INFILTRATION; ALLOYS AB The rate of composite formation via reactive metal penetration has been determined. The metal penetration depth (i.e., the reaction-layer thickness) was measured from cross sections of partially reacted samples. Samples were fabricated by immersing dense mullite preforms in a bath of molten aluminum at temperatures of 900 degrees-1300 degrees C and reacting the combination for up to 250 min. In general, the reaction-layer thickness increased linearly as the time increased. Penetration rates as high as 6.0 mm/h were measured; however, the aluminum penetration rate varied dramatically with time and temperature. The penetration rate increased when the reaction temperature was increased from 900 degrees C to 1100 degrees C, and the reaction-layer thickness increased linearly as the time increased in this temperature range. At temperatures of 1150 degrees C and above, reaction-layer formation slowed or stopped after a relatively short period of rapid linear growth, because of an increase in silicon concentration near the reaction interface. The duration of the rapid linear growth period decreased from 25 min at 1150 degrees C to <1 min at 1250 degrees C. At temperatures of 1300 degrees C and above, no reaction layer was detected by using optical microscopy. Kinetics data and transmission electron microscopy analysis suggest that the reaction was inhibited at higher reaction temperatures and longer times, because of silicon buildup and saturation at the reaction front. Calculations show that, as the reaction temperature increased, the silicon production increased faster than the silicon transport. The two rates were approximately equal at a temperature of 1100 degrees C. C1 Univ New Mexico, Albuquerque, NM 87106 USA. Adv Mat Lab, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. New Mexico Inst Min & Technol, Socorro, NM 87801 USA. RP Fahrenholtz, WG (reprint author), Univ New Mexico, Albuquerque, NM 87106 USA. OI Fahrenholtz, William/0000-0002-8497-0092 NR 32 TC 32 Z9 33 U1 1 U2 3 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 OCT PY 1998 VL 81 IS 10 BP 2533 EP 2541 PG 9 WC Materials Science, Ceramics SC Materials Science GA 129EM UT WOS:000076450800004 ER PT J AU Schilling, CH Garcia, VJ Smith, RM Roberts, RA AF Schilling, CH Garcia, VJ Smith, RM Roberts, RA TI Ultrasonic and mechanical behavior of green and partially sintered alumina: Effects of slurry consolidation chemistry SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID ELASTIC WAVE-PROPAGATION; PARTICLE PACKING; TENSILE-STRENGTH; HYDRATION FORCES; SURFACE-ENERGY; ZINC-OXIDE; CERAMICS; SUSPENSIONS; POWDERS; VELOCITY AB Green and partially sintered compacts of alpha-Al2O3 powder were made by filtration of aqueous suspensions under three conditions: (i) electrostatic stabilization without any organic additive, (ii) strong flocculation near the isoelectric point without any organic additive, and (iii) weak flocculation by the use of maltodextrin or oxalic acid additives, We evaluated relationships between the macroscopic and interparticle mechanical behavior of these compacts using model correlations with measurements of diametral compression, ultrasonic velocity, and ultrasonic attenuation. Although type iii green specimens were less dense than type i, type iii exhibited significant increases in velocity, macroscopic Young's modulus, interparticle-contact stiffness, and diametral compressive strength, suggesting that the mechanism of stiffening/strengthening entailed interparticle bridging of maltodextrin or oxalic acid, These properties were significantly reduced upon heating type iii specimens to 500 degrees C, suggesting that pyrolysis of surface-adsorbed maltodextrin and oxalic acid may have reduced the interparticle stiffness and strength. In contrast, negligible changes in these properties occurred upon heating type i specimens to the same temperature. Despite small increases in packing density, significant decreases in attenuation and significant increases in velocity, interparticle-contact stiffness, and Young's modulus occurred upon heating all specimens to greater than or equal to 700 degrees C, suggesting the formation of interparticle necks by solid-state sintering. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ, Ctr Nondestruct Evaluat, Ames, IA 50011 USA. Iowa State Univ, Dept Mech Engn, Ames, IA 50011 USA. RP Schilling, CH (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 83 TC 21 Z9 21 U1 1 U2 4 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD OCT PY 1998 VL 81 IS 10 BP 2629 EP 2639 PG 11 WC Materials Science, Ceramics SC Materials Science GA 129EM UT WOS:000076450800016 ER PT J AU Hay, JC Sun, EY Pharr, GM Becher, PF Alexander, KB AF Hay, JC Sun, EY Pharr, GM Becher, PF Alexander, KB TI Elastic anisotropy of beta-silicon nitride whiskers SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID MECHANICAL-PROPERTIES; INDENTATION EXPERIMENTS; PHASE CRYSTALLIZATION; OXYNITRIDE GLASSES; FRACTURE-TOUGHNESS; IN-SITU; CERAMICS; SI3N4; MICROSTRUCTURE; STRENGTH AB The elastic anisotropy of beta-silicon nitride was examined using nanoindentation techniques. A coarse-grained polycrystalline sample composed of whiskers up to 15 mu m in diameter and 100 mu m in length allowed for the positioning of small indentations near the centers of grains, where neighboring grains minimally affect the property measurements. The crystallographic directions along which measurements were made were determined from the grain geometries in polished sections. The primary directions of interest were parallel to the c-axis (indenter penetration parallel to the whisker axis) and in the basal plane (indenter penetration perpendicular to the whisker axis), for which the indentation moduli were found to be 450 and 310 GPa, respectively. An indentation mechanics model used to estimate the single-crystal elastic constants from the nanoindentation results shows that Young's moduli for beta-silicon nitride, which are similar to but not exactly the same as the moduli measured by nanoindentation techniques, vary from 540 GPa parallel to the c-axis to 280 GPa perpendicular to it. Hardness data, which also exhibit a strong anisotropy, are also presented. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Rice Univ, Dept Mat Sci, Houston, TX 77005 USA. RP Hay, JC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 53 TC 71 Z9 71 U1 5 U2 12 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 OCT PY 1998 VL 81 IS 10 BP 2661 EP 2669 PG 9 WC Materials Science, Ceramics SC Materials Science GA 129EM UT WOS:000076450800020 ER PT J AU Yang, JF Choa, YH Singh, JP Niihara, K AF Yang, JF Choa, YH Singh, JP Niihara, K TI Fabrication and mechanical properties of Si3N4/SiC nanocomposite with pressureless sintering and sinter-post-HIPing SO JOURNAL OF THE CERAMIC SOCIETY OF JAPAN LA English DT Article DE silicon nitride; silicon carbide; nanocomposite; pressureless sintering; HIP; mechanical properties ID SILICON-NITRIDE; FRACTURE-TOUGHNESS; MICROSTRUCTURE; CERAMICS; COMPOSITES; ADDITIONS; BEHAVIOR AB Si3N4/SiC composites containing 0-30 vol% SiC were fabricated by pressureless sintering and sinter-post-HIPing method using fine Si3N4 and nano-sized SiC powders. Specimens reached full density (>96% theoretical density (th. d.)) except the composites made by pressureless sintering which contained a small amount of sintering additives or a large amount of SiC. All composites with 10 mass% sintering additives reached full density (similar to 99% th. d.) by sinter-post-HIPing. The addition of SiC particles greatly influenced the grain morphology of the Si3N4 matrix. The average grain thickness, length and aspect ratio decreased with increasing SiC content because of grain boundary pinning by SiC particles. Also the mechanical properties were markedly dependent upon the fraction of SiC particle reinforcement, as well as matrix grain size and porosity. When the materials were pressureless sintered, the strength of the composite increased with SiC additions below 20 vol%. Further increase in the SIC content resulted in a corresponding decrease in strength. Maximum strength of 1150 MPa was attained at 20 vol% SiC addition. The increase in strength by addition of SiC is due to decrease of grain size of Si3N4 matrix grain size, and the decrease by further increase in SiC content is caused by porosity and SiC agglomerate. On the other hand, toughness decreased monotonically with SiC content. The strength of all samples was enhanced by sinter-post-HIPing without any change in fracture toughness. The strength of sintered samples with 10-15 vol% SiC increased by similar to 20% to 1260 MPa by post-HIPing. The increase in strength by post-HIPing was interpreted as being due to a decrease flaw size. C1 Osaka Univ, Inst Sci & Ind Res, Ibaraki, Osaka 5670047, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. RP Yang, JF (reprint author), Osaka Univ, Inst Sci & Ind Res, 8-1 Mihogaoka, Ibaraki, Osaka 5670047, Japan. RI Choa, Yongho/D-3625-2011 NR 26 TC 8 Z9 8 U1 0 U2 3 PU CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI PI TOKYO PA 22-17, HYAKUNIN-CHO 2-CHOME, SHINJUKU-KU, TOKYO, 169-0073, JAPAN SN 1882-0743 EI 1348-6535 J9 J CERAM SOC JPN JI J. Ceram. Soc. Jpn. PD OCT PY 1998 VL 106 IS 10 BP 951 EP 957 DI 10.2109/jcersj.106.951 PG 7 WC Materials Science, Ceramics SC Materials Science GA 130KD UT WOS:000076518500002 ER PT J AU Noll, JD Nicholson, MA Van Patten, PG Chung, CW Myrick, ML AF Noll, JD Nicholson, MA Van Patten, PG Chung, CW Myrick, ML TI Template electropolymerization of polypyrrole nanostructures on highly ordered pyrolytic graphite step and pit defects SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SCANNING TUNNELING MICROSCOPY; ELECTROCHEMICAL DEPOSITION; ELECTRON-TRANSFER; FILMS; GOLD; NUCLEATION; SURFACE; GROWTH; ELECTRODEPOSITION; NANOFABRICATION AB Polypyrrole nanostructures with diameters less than or equal to 10 nm have been electropolymerized using step and pit defects on highly ordered pyrolytic graphite (HOPG) as templates for electropolymerization. Step defects were naturally occurring, and pits were formed via oxidation of freshly cleaved surfaces of an HOPG wafer by heating at similar to 640 degrees C. Underpotential deposition of approximately similar to 80 mV caused polypyrrole to form only on the step and pit edges of HOPG at and not on the basal plane. The size of these nanostructures could be controlled by limiting the pyrrole polymerization time at anodic potentials. Recent modeling results allow the morphology of the deposition to be inferred, and we find the electrochemical data consistent with wire-shaped growth for up to 30 s at constant potential, after which the growth changes morphology. Scanning tunneling microscopy data confirm this result. Preliminary studies show that these polypyrrole nanostructures can be removed by sonication. C1 Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA. RP Noll, JD (reprint author), Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. OI Myrick, Michael/0000-0002-6905-0925 NR 58 TC 37 Z9 38 U1 1 U2 7 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD OCT PY 1998 VL 145 IS 10 BP 3320 EP 3328 DI 10.1149/1.1838806 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 125BF UT WOS:000076217000002 ER PT J AU Khaselev, O Turner, JA AF Khaselev, O Turner, JA TI Electrochemical stability of p-GaInP2 in aqueous electrolytes toward photoelectrochemical water splitting SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID EFFICIENT PHOTOASSISTED ELECTROLYSIS; SURFACE MODIFICATION; GA0.5IN0.5P; IMPEDANCE; INTERFACE AB With an eye toward developing a photoelectrochemical system for water splitting using p-GaInP2, the electrochemical stability of p-GaInP2 was studied in 10 M KOH. 3 M H2SO4, and a phosphate buffer of pH 7. It was found that in the dark, the p-GaInP2 electrode is susceptible to corrosion in all investigated solutions. Upon illumination, the anodic corrosion current increases. Under cathodic polarization in 10 M KOH, the p-GaInP3 electrode shows saturated photocurrent density, however the photocurrent slowly decreases with time due to the precipitation of an indium-enriched oxide. In 3 M H2SO4, the anodic process can be inhibited under relatively low cathodic potentials, and stable photocurrents can be obtained. In neutral solution, p-GaInP2 is covered by a semi-insulating oxide film and the observed photocurrent densities are much lower than those in 10 M KOH and 3 M H2SO4. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Khaselev, O (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 22 TC 60 Z9 60 U1 4 U2 38 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD OCT PY 1998 VL 145 IS 10 BP 3335 EP 3339 DI 10.1149/1.1838808 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 125BF UT WOS:000076217000004 ER PT J AU Ein-Eli, Y Lu, SH Rzeznik, MA AF Ein-Eli, Y Lu, SH Rzeznik, MA TI LiCuxMn2-xO4 spinels (0.1 <= x <= 0.5): A new class of cathode materials for Li batteries - II. In situ measurements SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article AB Electrochemical data obtained from lithium cycling in LiCuxMn2-xO4 spinels (0.1 less than or equal to x less than or equal to 0.5) show a remarkable, high ly reversible, electrochemical cycling behavior at 4.9 V. In situ X-ray absorption near edge structure spectroscopy revealed that this ultrahigh voltage is due to the existence of the Cu2+/Cu3+ redox couple. The origin of the high stability at the 5 V region was studied with the in situ X-ray diffraction technique. It was found that the unit cell dimension undergoes minimal change during charge-discharge cycles at the 5 V plateau. C1 Covalent Associates Inc, Woburn, MA 01801 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ein-Eli, Y (reprint author), Elect Fuel Ltd, IL-99000 Beit Shemesh, Israel. RI Ein-Eli, Yair/F-1370-2011 NR 10 TC 37 Z9 37 U1 1 U2 14 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD OCT PY 1998 VL 145 IS 10 BP 3383 EP 3386 DI 10.1149/1.1838816 PG 4 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 125BF UT WOS:000076217000012 ER PT J AU Bhattacharya, RN Batchelor, W Wiesner, H Hasoon, F Granata, JE Ramanathan, K Alleman, J Keane, J Mason, A Matson, RJ Noufi, RN AF Bhattacharya, RN Batchelor, W Wiesner, H Hasoon, F Granata, JE Ramanathan, K Alleman, J Keane, J Mason, A Matson, RJ Noufi, RN TI 14.1% CuIn1-xGaxSe2-based photovoltaic cells from electrodeposited precursors SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SOLAR-CELLS; THIN-FILMS AB We have fabricated 14.1% efficient CuIn1-xGaxSe2 (CIGS) based devices from electrodeposited precursors. As deposited precursors are Cu-rich films and are polycrystalline in nature. Additional In, Ga, and Se were added to the precursor films by physical evaporation to adjust the final composition to CuIn1-xGaxSe2. Addition of In and Ga and also selenization at high temperature are very crucial for obtaining high-efficiency devices. The X-ray analysis of the as-deposited precursor film indicates the presence of CIGS and Cu2Se phases. The X-ray analysis of the film after adjusting the composition of the final film shows only the CIGS phase. The films/devices have been characterized by inductively coupled plasma spectrometry, Auger electron spectroscopy, X-ray diffraction, electron-probe microanalysis, current-voltage characteristics, capacitance-voltage, and spectral response. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Bhattacharya, RN (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 13 TC 39 Z9 44 U1 1 U2 9 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD OCT PY 1998 VL 145 IS 10 BP 3435 EP 3440 DI 10.1149/1.1838823 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 125BF UT WOS:000076217000019 ER PT J AU Lee, SH Gao, W Tracy, CE Branz, HM Benson, DK Deb, S AF Lee, SH Gao, W Tracy, CE Branz, HM Benson, DK Deb, S TI Monolithic, self-powered photovoltaic-electrochromic coating for windows SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID THIN-FILMS; DEVICES AB We report progress in the development of a monolithic, self-powered photovoltaic-electrochromic coating for energy-conserving windows. The coating employs an all solid-state electrochromic device based on Li-doped WO, as an optical transmittance modulator and a wide-bandgap amorphous SiC alloy (a-SiC:H) photovoltaic (PV) cell as an integral power source. The electrochromic device is deposited together with the PV device as a monolithic coating on a glass substrate. The active Li-ion concentration in the electrochromic device was optimized based on the thermodynamics and optical properties of the electrochromic and ion-storage layers. Electrical and electro-optic characteristics of the multilayer coatings are reported. The monolithic tandem PV-electrochromic coating shows a transmittance variation of more than 60% under 1 sun illumination. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Lee, SH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Lee, Sehee/A-5989-2011 NR 24 TC 27 Z9 28 U1 1 U2 16 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD OCT PY 1998 VL 145 IS 10 BP 3545 EP 3550 DI 10.1149/1.1838840 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 125BF UT WOS:000076217000036 ER PT J AU Sebastian, PJ Calixto, ME Bhattacharya, RN Noufi, R AF Sebastian, PJ Calixto, ME Bhattacharya, RN Noufi, R TI A 10% Cu(In,Ga)Se-2 based photovoltaic structure formed by electrodeposition and subsequent thermal processing SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID CUINSE2 THIN-FILMS AB CuIn1-xGaxSe2 (CIGS) thin films were formed from an electrodeposited CuInSe2 (CIS) precursor by thermal processing in vacuum in which the film stoichiometry was adjusted by adding In, Ga, and Se. The structure, composition, morphology and opto-electronic properties of the as-deposited and selenized CIS precursors were characterized by various techniques. A 10% CIGS based thin film solar cell was developed using the electrodeposited and thermally processed film. The cell structure consisted of Mo/CIGS/CdS/ZnO/MgF2. The cell parameters such as J(sc), V-oc, FF, and eta were determined from I-V characterization of the cell. C1 Univ Nacl Autonoma Mexico, Energy Res Ctr, Solar H2 Fuel Cell Grp, Temixco 62580, Morelos, Mexico. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sebastian, PJ (reprint author), Univ Nacl Autonoma Mexico, Energy Res Ctr, Solar H2 Fuel Cell Grp, Temixco 62580, Morelos, Mexico. OI Calixto, Ma. Estela/0000-0002-9611-3346 NR 12 TC 9 Z9 9 U1 0 U2 8 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 OCT PY 1998 VL 145 IS 10 BP 3613 EP 3615 DI 10.1149/1.1838851 PG 3 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 125BF UT WOS:000076217000047 ER PT J AU Steif, PS Rubal, MP Gray, GT Pereira, JM AF Steif, PS Rubal, MP Gray, GT Pereira, JM TI Damage in gamma titanium aluminides due to small particle impacts SO JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS LA English DT Article; Proceedings Paper CT Symposium on the Dynamic Deformation and Failure Mechanics of Materials, Honoring Professor R J Clifton on the Occasion of his 60th Birthday CY MAY 22-24, 1997 CL PASADENA, CALIFORNIA DE ductility; contact mechanics; finite elements; plate impact; intermetallics (not included in list) AB Initiation of cracking due to small particle impacts on low ductility intermetallics is investigated experimentally and theoretically. The gamma titanium aluminide alloys of interest which are being considered for elevated temperature structural applications in aircraft engines exhibit tensile ductilities on the order of 1-2%. Cracking due to any source, including small particle impacts, is of concern given the rapid growth of cracks in fatigue. This investigation focuses on a model geometry which reproduces the rear face cracking that is induced by a small particle impinging on an air foil leading edge. Small steer spheres are projected onto thin plates at velocities ranging from 76 to 305 m/s; cracking is thereby induced on the rear surface of the plates. Through finite element analyses of the dynamic impact event and some analytical estimates, we examine the hypothesis that crack initiation due to small particle impacts can be correlated with material ductility and with the severity and spatial extent of the straining during the impact event. In addition, with the use of static indentation tests in which similar strain distributions are present, some insight is gained into the difference in ductility between high and low strain rates. (C) 1998 Elsevier Science Ltd: All rights reserved. C1 Carnegie Mellon Univ, Dept Mech Engn, Pittsburgh, PA 15213 USA. Univ Calif Los Alamos Natl Lab, MST Grp 5, Los Alamos, NM 87545 USA. NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. RP Steif, PS (reprint author), Carnegie Mellon Univ, Dept Mech Engn, Schenley Pk, Pittsburgh, PA 15213 USA. RI Steif, Paul/D-2459-2013 NR 19 TC 9 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-5096 J9 J MECH PHYS SOLIDS JI J. Mech. Phys. Solids PD OCT PY 1998 VL 46 IS 10 BP 2069 EP 2086 PG 18 WC Materials Science, Multidisciplinary; Mechanics; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 146GC UT WOS:000077420100021 ER PT J AU Norton, SJ Vo-Dinh, T AF Norton, SJ Vo-Dinh, T TI Diffraction tomographic imaging with photon density waves: an explicit solution SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID MEDICINE AB An explicit formula is derived for reconstructing tissue inhomogeneities from scattered photon-density waves. When intensity-modulated light is used as a source, such waves obey a Helmholtz equation with a complex wave number. A process of analytical continuation in the spatial-frequency domain is used to make this wave number real, whereupon inversion formulas based on conventional diffraction tomography are applied to invert the data to yield an image. In this way an explicit solution to the inverse problem can be derived within the Born approximation. Here the spatially varying quantity imaged is a linear combination of the transport scattering and absorption coefficients. Data are assumed measured at one modulation frequency, but multiple modulation frequencies could in principle be used to generate independent images of the scattering and absorption coefficients. (C) 1998 Optical Society of America. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Norton, SJ (reprint author), Geophex Ltd, 605 Mercury St, Raleigh, NC 27603 USA. NR 8 TC 20 Z9 20 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD OCT PY 1998 VL 15 IS 10 BP 2670 EP 2677 DI 10.1364/JOSAA.15.002670 PG 8 WC Optics SC Optics GA 123VQ UT WOS:000076146500007 ER PT J AU Reichardt, TA Lucht, RP Danehy, PM Farrow, RL AF Reichardt, TA Lucht, RP Danehy, PM Farrow, RL TI Theoretical investigation of the forward phase-matched geometry for degenerate four-wave mixing spectroscopy SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID 4-WAVE-MIXING SPECTROSCOPY; FLAME; INTENSITIES; DEPENDENCE; RESOLUTION; SATURATION; SYSTEMS; LASER; DFWM AB We examine theoretically the degenerate four-wave mixing (DFWM) signal intensities and line shapes obtained with the forward phase-matched geometry in which all beams propagate in the same direction and compare the results to those of the phase-conjugate geometry with counterpropagating pump beams. To examine the forward phase-matched geometry, we modify a theoretical approach used previously to calculate phase-conjugate DFWM signal intensities. This theoretical approach, which involves numerical integration of the time-dependent density-matrix equations, is validated for the forward phase-matched geometry by comparison of our calculated line shapes to both a perturbative solution and to experimental data. This methodology is then used to compare the signal intensities and line shapes obtained with the forward phase-matched geometry and the phase-conjugate geometry in the perturbative (low laser power) and saturated (high laser power) regimes. In the perturbative regime the forward phase-matched signal exhibits less sensitivity to the Doppler linewidth. At pump laser intensities approximately equal to the saturation intensity the signal for the forward phase-matched geometry is stronger than that for the phase-conjugate geometry for primarily Doppler-broadened resonances, assuming the same probe volume for both geometries. These advantages warrant fur ther investigations employing the forward phase-matched configuration for DFWM measurements of gasphase species. (C) 1998 Optical Society of America [S0740-3224(98)01819-4]. C1 Univ Illinois, Dept Mech & Ind Engn, Laser Diagnost Lab, Urbana, IL 61801 USA. Australian Natl Univ Fac, Dept Phys, Canberra, ACT 0200, Australia. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Lucht, RP (reprint author), Univ Illinois, Dept Mech & Ind Engn, Laser Diagnost Lab, 1206 W Green St, Urbana, IL 61801 USA. NR 32 TC 15 Z9 15 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD OCT PY 1998 VL 15 IS 10 BP 2566 EP 2572 DI 10.1364/JOSAB.15.002566 PG 7 WC Optics SC Optics GA 127WY UT WOS:000076374600008 ER PT J AU Ikeda, H Itoh, S Adams, MA Fernandez-Baca, JA AF Ikeda, H Itoh, S Adams, MA Fernandez-Baca, JA TI Crossover from homogeneous to fractal excitations in the near-percolating Heisenberg antiferromagnet RbMn0.39Mg0.61F3 SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Letter DE magnetic excitation; percolating magnet; fractal; fracton; magnon; inelastic neutron scattering ID SILICA AEROGELS; SPIN-WAVES; THRESHOLD; DIFFUSION; DENSITY; STATES AB Neutron inelastic scattering experiments on the near-percolating Hesisenberg antiferromagnet, RhMn0.39Mg0.61F3, were performed using a high energy-resolution spectrometer (15 mu eV). The results reveal a crossover from magnon excitations at small wave-vectors to over-damped fracton excitations at large wave-vectors. This evinces experimentally that the atomic connectivity in an infinite percolating network looks homogeneous at wave-vectors smaller than a crossover wave-vector, as predicted by the theory. C1 KEK, High Energy Accelerator Res Org, Neutron Sci Lab, Tsukuba, Ibaraki 3050801, Japan. Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Ikeda, H (reprint author), KEK, High Energy Accelerator Res Org, Neutron Sci Lab, Oho 1-1, Tsukuba, Ibaraki 3050801, Japan. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 13 TC 3 Z9 3 U1 0 U2 1 PU PHYSICAL SOC JAPAN PI TOKYO PA YUSHIMA URBAN BUILDING 5F, 2-31-22 YUSHIMA, BUNKYO-KU, TOKYO, 113-0034, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD OCT PY 1998 VL 67 IS 10 BP 3376 EP 3379 DI 10.1143/JPSJ.67.3376 PG 4 WC Physics, Multidisciplinary SC Physics GA 134CC UT WOS:000076724400014 ER PT J AU Sahai, V AF Sahai, V TI Predicting interfacial contact conductance and gap formation of investment cast alloy 718 SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER LA English DT Article ID MODELS AB Investment casting foundries increasingly rely on numerical simulations of their casting processes to enhance quality and reduce costs. An important aspect of numerical simulations is the interfacial heat transfer between the solidifying metal and the mold. Most codes use the concept of a contact conductance to model this heat transfer. The contact conductance varies during solidification as the mold expands and the metal shrinks, leading to the formation of a gap and significantly reduced contact conductance, Very little data are available for the estimation of contact conductance, particularly for the superalloys used in the aerospace industry. This paper reports on experimental and numerical results for the determination of contact conductance for an axisymmetric casting of alloy 718, The heat transfer code TOPAZ2D, in conjunction with an inverse method is used for the numerical simulation of this inverse heat transfer problem. The effects of variation of mold properties, mold thickness, and mold thermocouple locations on contact conductance are considered. The predicted gap widths are compared to actual measurements. Finally, the applicability of the technique is discussed. C1 Auburn Univ, Auburn, AL 36830 USA. RP Sahai, V (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L140, Livermore, CA 94550 USA. NR 11 TC 5 Z9 5 U1 1 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0887-8722 J9 J THERMOPHYS HEAT TR JI J. Thermophys. Heat Transf. PD OCT-DEC PY 1998 VL 12 IS 4 BP 562 EP 566 DI 10.2514/2.6376 PG 5 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 132CM UT WOS:000076612500016 ER PT J AU Bhatia, CS Anders, S Brown, IG Bobb, K Hsiao, R Bogy, DB AF Bhatia, CS Anders, S Brown, IG Bobb, K Hsiao, R Bogy, DB TI Ultra-thin overcoats for the head/disk interface tribology SO JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID AMORPHOUS-CARBON FILMS; DEPOSITION; DIAMOND; VACUUM; MEDIA AB Cathodic are deposition forms ultra-thin amorphous hard carbon films of high sp(3) content, high hardness, and low coefficient of friction. These properties make it of great interest for head/disk interface application, in particular for contact recording. In many cases, the tribological properties of the head disk interface could be improved by factors up to ten by applying cathodic are overcoats to the slider or disk-surface. This paper reviews the results of cathodic are ultra-thin (2-10 nm) carbon overcoats for head/disk interface tribological applications. C1 IBM Corp, SSD, San Jose, CA 95193 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. RP Bhatia, CS (reprint author), IBM Corp, SSD, 5600 Cottle Rd, San Jose, CA 95193 USA. RI Raoux, Simone/G-3920-2016 NR 14 TC 31 Z9 32 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0742-4787 J9 J TRIBOL-T ASME JI J. Tribol.-Trans. ASME PD OCT PY 1998 VL 120 IS 4 BP 795 EP 799 DI 10.1115/1.2833781 PG 5 WC Engineering, Mechanical SC Engineering GA 133FJ UT WOS:000076675900021 ER PT J AU Doebling, SW Peterson, LD Alvin, KF AF Doebling, SW Peterson, LD Alvin, KF TI Experimental determination of local structural stiffness by disassembly of measured flexibility matrices SO JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME LA English DT Article ID DAMAGE DETECTION; IDENTIFICATION AB A new method is presented for identifying the local stiffness of a structure from vibration test data. The method is based on a projection of the experimentally measured flexibility matrix onto the strain energy distribution in local elements or regional superelements. Using both a presumed connectivity and a presumed strain energy distribution pattern, the method forms a well-determined linear least squares problem for elemental stiffness matrix eigenvalues. These eigenvalues are directly proportional to the stiffnesses of individual elements or superelements, including the cross-sectional bending stiffnesses of beams, plates, and shells, for example, An important part of the methodology is the formulation of nodal degrees of freedom as functions of the measured sensor degrees of freedom to account for the location offsets which are present in physical sensor measurements. Numerical and experimental results are presented which show the application of the approach to example problems. C1 Univ Calif Los Alamos Natl Lab, Engn Anal Grp, ESA EA, Engn Sci & Applicat Div, Los Alamos, NM 87545 USA. RP Doebling, SW (reprint author), Univ Calif Los Alamos Natl Lab, Engn Anal Grp, ESA EA, Engn Sci & Applicat Div, M-S P946, Los Alamos, NM 87545 USA. EM doebling@lanl.gov; Lee.Peterson@Colorado.EDU; kfalvin@sandia.gov NR 14 TC 35 Z9 36 U1 0 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1048-9002 J9 J VIB ACOUST JI J. Vib. Acoust.-Trans. ASME PD OCT PY 1998 VL 120 IS 4 BP 949 EP 957 DI 10.1115/1.2893925 PG 9 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 129YU UT WOS:000076492300018 ER PT J AU Aikens, DM AF Aikens, DM TI Fusion research improves optics manufacturing SO LASER FOCUS WORLD LA English DT Article AB Changes in specifications and technology required for fabricating precision optics for NIF could have lasting impact on the entire optics community. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Aikens, DM (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 E Ave L-527, Livermore, CA 94550 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU PENNWELL PUBL CO PI NASHUA PA 5TH FLOOR TEN TARA BOULEVARD, NASHUA, NH 03062-2801 USA SN 0740-2511 J9 LASER FOCUS WORLD JI Laser Focus World PD OCT PY 1998 VL 34 IS 10 BP S17 EP + PG 4 WC Optics SC Optics GA 126DB UT WOS:000076276700033 ER PT J AU Burton, H AF Burton, H TI Women's science: Learning and succeeding from the margins. SO LIBRARY JOURNAL LA English DT Book Review C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Burton, H (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD OCT 1 PY 1998 VL 123 IS 16 BP 128 EP 128 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 124AD UT WOS:000076157400232 ER PT J AU Gabriel, JM Gray, TA Stubbs, L Saitoh, S Ohta, T Nicholls, RD AF Gabriel, JM Gray, TA Stubbs, L Saitoh, S Ohta, T Nicholls, RD TI Structure and function correlations at the imprinted mouse Snrpn locus SO MAMMALIAN GENOME LA English DT Article ID PRADER-WILLI-SYNDROME; MATERNAL-SPECIFIC METHYLATION; ANGELMAN-SYNDROME GENE; DNA METHYLATION; CONTROL REGION; HUMAN THYMUS; NECDIN GENE; IGF2R LOCUS; CPG ISLAND; EXPRESSION AB The human SNRPN gene maps within Chromosome (Chr) 15q11-q13, the region responsible for Prader-Willi syndrome (PWS) and Angelman syndrome (AS). As one of several 15q11-q13 transcripts expressed from the paternal allele-only, SNRPN is a candidate gene to explain at least some of the PWS phenotype in human and in genetic mouse models. The promoter and first exon of the SNRPN gene also correspond to an imprinting center element responsible for resetting of the maternal to paternal imprints within 15q11-q13 during spermatogenesis. Through characterization of the imprinted murine Snrpn locus in mouse Chr 7C, we have found that the gene structure is very similar to the human, with ten conserved exons spanning 22 kb, the last seven of which are tightly clustered. The promoter of Snrpn is differentially methylated in ES cells and adult tissues, supporting a role for DNA methylation at this site in somatic establishment and/or maintenance of Snrpn imprinting. The first intron of the mouse and human genes contains structurally conserved G-rich clustered repeats which may play a role in establishing DNA methylation patterns associated with imprinting of this gene. On the basis of the conserved structural and imprinted features of the human SNRPN and mouse Snrpn genes, we suggest that imprinting mechanisms are conserved between human and mouse. C1 Case Western Reserve Univ, Sch Med, Dept Genet, Cleveland, OH 44106 USA. Univ Hosp Cleveland, Ctr Human Genet, Cleveland, OH 44106 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Human Genome, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Nicholls, RD (reprint author), Case Western Reserve Univ, Sch Med, Dept Genet, 10900 Euclid Ave, Cleveland, OH 44106 USA. OI Stubbs, Lisa/0000-0002-9556-1972 FU NICHD NIH HHS [HD31491]; NIGMS NIH HHS [GM08613-02, GM18306-02] NR 47 TC 34 Z9 34 U1 0 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0938-8990 J9 MAMM GENOME JI Mamm. Genome PD OCT PY 1998 VL 9 IS 10 BP 788 EP 793 DI 10.1007/s003359900868 PG 6 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity GA 121VT UT WOS:000076035900003 PM 9745031 ER PT J AU Hubbell, JM Sisson, JB AF Hubbell, JM Sisson, JB TI Advanced tensiometer for water potential measurements SO MEASUREMENTS & CONTROL LA English DT Article AB Tensiometers are required for measuring soil water potential at depths exceeding several meters to quantify the direction and rate of soil water movement. This article describes a permanently installed tensiometer (advanced tensiometer) to measure soil water potentials at any depth below land surface. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83401 USA. RP Hubbell, JM (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83401 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU MEASUREMENTS & DATA CORP PI PITTSBURGH PA 2994 W LIBERTY AVE, PITTSBURGH, PA 15216 USA SN 0148-0057 J9 MEAS CONTROL-US JI Meas. Control PD OCT PY 1998 IS 191 BP 81 EP 85 PG 5 WC Automation & Control Systems; Instruments & Instrumentation SC Automation & Control Systems; Instruments & Instrumentation GA 143HJ UT WOS:000077249000005 ER PT J AU Barenblatt, GI Chorin, AJ AF Barenblatt, GI Chorin, AJ TI Turbulence: An old challenge and new perspectives SO MECCANICA LA English DT Article; Proceedings Paper CT International Conference on Topics in Fluid Mechanics in Memory of Professor Carlo Ferrari CY APR 03-04, 1998 CL TURIN, ITALY DE turbulence; wall-bounded turbulent shear flows; scaling laws in turbulence; local structure of turbulence; fluid mechanics ID SCALING LAWS; SHEAR FLOWS; KOLMOGOROV CONSTANT; LOCAL-STRUCTURE; STATISTICS AB Turbulence at very large Reynolds numbers (often called developed turbulence) is widely considered to be one of the happier provinces of the turbulence realm, as it is widely thought that two of its basic results are well-established, and have a chance to enter, basically untouched, into a future complete theory of turbulence. These results are the von Karman-Prandtl universal logarithmic law in the wall-region of wall-bounded turbulent shear flow, and the Kolmogorov-Obukhov scaling laws for the local structure of developed turbulent flow. However, doubts have been expressed over the years about the fluid mechanical assumptions that underlie these laws. After a concise review of the problem of turbulence as a whole we will show in the present paper that the von Karman-Prandtl universal logarithmic law is based on an assumption which, though plausible, in fact is not quite correct. We will come to the conclusion, based on theoretical considerations and on processing of experimental data, that the universal logarithmic law does not describe the real features of developed turbulent wall-bounded flow of viscous fluid; it should be jettisoned and replaced by a different law, a scaling law. Experimental evidence for the local structure of turbulent flows is now not sufficiently well-established to allow a similarly definite conclusion. However, the application of the new approach presented here makes it very plausible that the classical, non-modified version of Kolmogorov-Obukhov 'K-41' laws gives an adequate description of the local features of developed turbulent flows. C1 Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Barenblatt, GI (reprint author), Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. NR 70 TC 5 Z9 6 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0025-6455 J9 MECCANICA JI Meccanica PD OCT PY 1998 VL 33 IS 5 BP 445 EP 468 DI 10.1023/A:1004312409376 PG 24 WC Mechanics SC Mechanics GA 144MM UT WOS:000077318400004 ER PT J AU Howard, BV Mayer-Davis, EJ Goff, D Zaccaro, DJ Laws, A Robbins, DC Saad, MF Selby, J Hamman, RF Krauss, RM Haffner, SM AF Howard, BV Mayer-Davis, EJ Goff, D Zaccaro, DJ Laws, A Robbins, DC Saad, MF Selby, J Hamman, RF Krauss, RM Haffner, SM TI Relationships between insulin resistance and lipoproteins in nondiabetic African Americans, Hispanics, and non-Hispanic whites: The Insulin Resistance Atherosclerosis Study SO METABOLISM-CLINICAL AND EXPERIMENTAL LA English DT Article ID DEPENDENT DIABETES-MELLITUS; CARDIOVASCULAR RISK-FACTORS; CORONARY HEART-DISEASE; GLUCOSE-TOLERANCE TEST; MINIMAL MODEL; DENSITY LIPOPROTEINS; PLASMA TRIGLYCERIDE; BLOOD-PRESSURE; HEALTHY-MEN; SENSITIVITY AB The study purpose was to explore the association between dyslipidemia and insulin resistance in three ethnic groups. The Insulin Resistance Atherosclerosis Study (IRAS) is a multicenter epidemiologic study conducted at four clinical centers in California, Texas, and Colorado. The study population for this analysis consisted of 931 non-Hispanic white, African American, and Hispanic men and women (aged 45 to 64 years) without diabetes. The IRAS clinical examinations included lipoprotein measures, a 75-g glucose tolerance test, and the frequently sampled intravenous glucose tolerance (FSIGT) test. The results show a consistent relationship between insulin-mediated glucose disposal and dyslipidemia in African American, Hispanic, and non-Hispanic white men and women. Further, LDL size was inversely associated with insulin resistance in all three ethnic groups. These findings indicate that dyslipidemia is a fundamental part of the insulin resistance syndrome in all of the ethnic groups studied. Copyright (C) 1998 by W.B. Saunders Company. C1 Medlant Res Inst, Washington, DC 20010 USA. Wake Forest Univ, Bowman Gray Sch Med, Dept Publ Hlth Sci, Winston Salem, NC 27103 USA. Stanford Univ, Sch Med, Dept Med, Palo Alto, CA 94304 USA. Univ So Calif, Sch Med, Dept Med, Los Angeles, CA 90033 USA. Kaiser Permanente, Div Res, Oakland, CA USA. Univ Colorado, Hlth Sci Ctr, Dept Prevent Med & Biometr, Denver, CO 80262 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Donner Labs, Berkeley, CA USA. Univ Texas, Hlth Sci Ctr, Dept Med, San Antonio, TX 78284 USA. RP Howard, BV (reprint author), Medlant Res Inst, 108 Irving St NW, Washington, DC 20010 USA. FU NHLBI NIH HHS [HL47887, HL47889, HL47890] NR 60 TC 61 Z9 62 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0026-0495 J9 METABOLISM JI Metab.-Clin. Exp. PD OCT PY 1998 VL 47 IS 10 BP 1174 EP 1179 DI 10.1016/S0026-0495(98)90319-5 PG 6 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 128FP UT WOS:000076395300002 PM 9781617 ER PT J AU Perez, RJ Jiang, HG Dogan, CP Lavernia, EJ AF Perez, RJ Jiang, HG Dogan, CP Lavernia, EJ TI Grain growth of nanocrystalline cryomilled Fe-Al powders SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID BOUNDARY SEGREGATION; THERMAL-STABILITY; EVOLUTION; ALLOYS AB Nanocrystalline Fe-xAl (x = 0, 2.6, or 10 wt pet) powders have been prepared using cryogenic mechanical alloying (cryomilling). The extremely low rate of diffusion of Al in Fe at the process temperature (-196 degrees C) effectively limits dissolution of Al in the nanocrystalline alpha Fe grains. Thermal stability against grain growth in the cryomilled Fe-Al mixtures is found to be much greater than that of identically prepared pure nanocrystalline Fe. Heat treatment of the cryomilled Fe-Al materials results in a highly inhomogeneous distribution of grain size and microchemistry. The observed thermal stability is evaluated in terms of Zener pinning, solute drag, and chemical ordering mechanisms. C1 Boeing Co, Mat & Proc Engn Space Syst Div, Downey, CA USA. Univ Calif Irvine, Dept Chem Engn & Mat Sci, Irvine, CA 92697 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Perez, RJ (reprint author), Boeing Co, Mat & Proc Engn Space Syst Div, Downey, CA USA. NR 36 TC 69 Z9 71 U1 0 U2 13 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD OCT PY 1998 VL 29 IS 10 BP 2469 EP 2475 DI 10.1007/s11661-998-0218-7 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 128XK UT WOS:000076433500002 ER PT J AU Bloyer, DR Rao, KTV Ritchie, RO AF Bloyer, DR Rao, KTV Ritchie, RO TI Fracture toughness and R-curve behavior of laminated brittle-matrix composites SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID FATIGUE-CRACK-PROPAGATION; HIGH-TEMPERATURE INTERMETALLICS; DUCTILE-PHASE; MOLYBDENUM DISILICIDE; TOUGHENING MECHANISMS; LAYERED MATERIALS; BRIDGED CRACKS; GROWTH; REINFORCEMENTS; RESISTANCE AB The fracture toughness and resistance-curve behavior of relatively coarse-scale, niobium/niobium aluminide (Nb/Nb3Al) laminated composites have been examined and compared to other Nb/Nb3Al composites with (in situ) Nb particulate or microlaminate reinforcements. The addition of high aspect-ratio Nb reinforcements, in the form of 20 vol. pet of 50- to 250-mu m-thick layers, was seen to improve the toughness of the Nb3Al intermetallic matrix by well over an order of magnitude, with the toughness increasing with Nb layer thickness. The orientation of the laminate had a small effect on crack-growth resistance with optimal properties being found in the crack arrester, as compared to the crack divider, orientation. The high fracture toughness of these laminates was primarily attributed to large (similar to 1- to 6-mm) crack-bridging zones formed by intact Nb layers in the crack wake; these zones were of sufficient size that large-scale bridging (LSB) conditions generally prevailed in the samples tested. Resistance-curve modeling using weight function methods permitted the determination of simple approximations for the bridging tractions, which were then used to make small-scale bridging (SSB) predictions for the steady-state toughness of each laminate. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Guidant Corp, Vasc Intervent Grp, Santa Clara, CA 95052 USA. RP Bloyer, DR (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RI Ritchie, Robert/A-8066-2008 OI Ritchie, Robert/0000-0002-0501-6998 NR 58 TC 61 Z9 63 U1 0 U2 15 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1073-5623 EI 1543-1940 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD OCT PY 1998 VL 29 IS 10 BP 2483 EP 2496 DI 10.1007/s11661-998-0220-0 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 128XK UT WOS:000076433500004 ER PT J AU Galbraith, MP Feng, SF Borneman, J Triplett, EW de Bruijn, FJ Rossbach, S AF Galbraith, MP Feng, SF Borneman, J Triplett, EW de Bruijn, FJ Rossbach, S TI A functional myo-inositol catabolism pathway is essential for rhizopine utilization by Sinorhizobium meliloti SO MICROBIOLOGY-SGM LA English DT Article DE Sinorhizobium meliloti; rhizopine catabolism; inositol catabolism; idhA; myo-inositol dehydrogenase ID OPINE-LIKE COMPOUND; RHIZOBIUM-MELILOTI; BACILLUS-SUBTILIS; GENETIC-CHARACTERIZATION; ALFALFA NODULES; EXPRESSION; SEQUENCE; CLONING; MUTANTS; IDENTIFICATION AB Rhizopine (L-3-O-methyl-scyllo-inosamine) is a symbiosis-specific compound found in alfalfa nodules induced by specific Sinorhizobium meliloti strains. It has been postulated that rhizobial strains able to synthesize and catabolize rhizopine gain a competitive advantage in the rhizosphere. The pathway of rhizopine degradation is analysed here. Since rhizopine is an inositol derivative, it was tested whether inositol catabolism is involved in rhizopine utilization. A genetic locus required for the catabolism of inositol as sole carbon source was cloned from S. meliloti. This locus was delimited by transposon Tn5 mutagenesis and its DNA sequence was determined. Based on DNA similarity studies and enzyme assays, this genetic region was shown to encode an S. meliloti myo-inositol dehydrogenase. Strains that harboured a mutation in the myo-inositol dehydrogenase gene (idhA) did not display myoinositol dehydrogenase activity, were unable to utilize myo-inositol as sole carbon/energy source, and were unable to catabolize rhizopine. Thus, myoinositol dehydrogenase activity is essential for rhizopine utilization in S. meliloti. C1 Western Michigan Univ, Dept Biol Sci, Kalamazoo, MI 49008 USA. Univ Wisconsin, Dept Agron, Madison, WI 53706 USA. Univ Wisconsin, Ctr Study Nitrogen Fixat, Madison, WI 53706 USA. Michigan State Univ, NSF, Ctr Microbial Ecol, Dept Microbiol,MSU DOE Plant Res Lab, E Lansing, MI 48824 USA. RP Rossbach, S (reprint author), Western Michigan Univ, Dept Biol Sci, Kalamazoo, MI 49008 USA. EM Silvia.Rossbach@wmich.edu NR 44 TC 42 Z9 45 U1 0 U2 3 PU SOC GENERAL MICROBIOLOGY PI READING PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING RG7 1AG, BERKS, ENGLAND SN 1350-0872 J9 MICROBIOL-SGM JI Microbiology-(UK) PD OCT PY 1998 VL 144 BP 2915 EP 2924 PN 10 PG 10 WC Microbiology SC Microbiology GA 130PH UT WOS:000076528100026 PM 9802033 ER PT J AU Kerschhofer, L Dupas, C Liu, M Sharp, TG Durham, WB Rubie, DC AF Kerschhofer, L Dupas, C Liu, M Sharp, TG Durham, WB Rubie, DC TI Polymorphic transformations between olivine, wadsleyite and ringwoodite: mechanisms of intracrystalline nucleation and the role of elastic strain SO MINERALOGICAL MAGAZINE LA English DT Article DE phase transformations; olivine; wadsleyite; ringwoodite; subduction zones ID BETA-PHASE TRANSFORMATION; SUBDUCTION ZONE CONDITIONS; SPINEL TRANSFORMATION; DEEP EARTHQUAKES; SYSTEM MG2SIO4-FE2SIO4; OCEANIC LITHOSPHERE; ELECTRON-MICROSCOPY; TRANSITION; PRESSURE; KINETICS AB Kinetic models and rate equations for polymorphic reconstructive phase transformations in polycrystalline aggregates are usually based on the assumptions that (a) the product phase nucleates on grain boundaries in the reactant phase and (b) growth rates of the product phase remain constant with time at fixed P-T. Recent observations of experimentally-induced transformations between (Mg,Fe)(2)SiO4 olivine (alpha) and its high pressure polymorphs, wadsleyite (beta) and ringwoodite (gamma), demonstrate that both these assumptions can be invalid, thus complicating the extrapolation of experimental kinetic data. Incoherent grain boundary nucleation appears to have dominated in most previous experimental studies of the alpha-beta-gamma transformations because of the use of starting materials with small (<10-20 mu m) grain sizes. In contrast, when large (0.6 mm) olivine single crystals are reacted, intracrystalline nucleation of both beta and gamma becomes the dominant mechanism, particularly when the P-T conditions significantly overstep the equilibrium boundary. At pressures of 18-20 GPa intracrystalline nucleation involves (i) the formation of stacking faults in the olivine, (ii) coherent nucleation of gamma-lamellae on these faults and (iii) nucleation of beta an gamma. In other experiments, intracrystalline nucleation is also observed during the beta-gamma transformation. In this case coherent nucleation of gamma appears to occur at the intersections of dislocations with (010) stacking faults in beta, which suggests that the nucleation rate is stress dependent. Reaction rims of beta/gamma form at the margins of the olivine single crystals by grain boundary nucleation. Measurements of growth distance as a function of time indicate that the growth rate of these rims decreases towards zero as transformation progresses. The growth rate slows because of the decrease in the magnitude of the Gibbs free energy (stored elastic strain energy) that develops as a consequence of the large volume change of transformation. On a Longer time scale, growth kinetics may be controlled by viscoelastic relaxation. C1 Univ Bayreuth, Bayer Geoinst, D-95440 Bayreuth, Germany. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kerschhofer, L (reprint author), WWU Munster, Inst F Planetol, Munster, Germany. NR 69 TC 46 Z9 46 U1 2 U2 13 PU MINERALOGICAL SOCIETY PI LONDON PA 41 QUEENS GATE, LONDON, ENGLAND SW7 5HR SN 0026-461X J9 MINERAL MAG JI Mineral. Mag. PD OCT PY 1998 VL 62 IS 5 BP 617 EP 638 DI 10.1180/002646198548016 PG 22 WC Mineralogy SC Mineralogy GA 134VA UT WOS:000076763300005 ER PT J AU Nickoloff, JA Spirio, LN Reynolds, RJ AF Nickoloff, JA Spirio, LN Reynolds, RJ TI A comparison of calcium phosphate coprecipitation and electroporation - Implications for studies on the genetic effects of DNA damage SO MOLECULAR BIOTECHNOLOGY LA English DT Article DE homologous recombination; nonhomologous recombination; DNA double-strand breaks ID MOUSE L-CELLS; DOUBLE-STRAND BREAKS; MAMMALIAN-CELLS; HOMOLOGOUS RECOMBINATION; MISMATCH REPAIR; HIGH-FREQUENCY; EXTRACHROMOSOMAL RECOMBINATION; ATAXIA-TELANGIECTASIA; MUTATION FREQUENCY; TRANSFECTED DNA AB Plasmid-based transfection assays provide a rapid means to measure homologous and nonhomologous recombination in mammalian cells. Often it is of interest to examine the stimulation of recombination by DNA damage induced by radiation, genotoxic chemicals, or nucleases. Transfection is frequently performed by using calcium phosphate coprecipitation (CPP), because this method is well suited for handling large sample sets, and it does not require expensive reagents or equipment. Alternative transfection methods include lipofection, microinjection, and electroporation. Since DNA strand breaks are:known to stimulate both homologous and nonhomologous recombination, the induction of nonspecific damage during transfection would increase background recombination levels and thereby reduce the sensitivity of assays designed to detect the stimulation of recombination by experimentally induced DNA damage. In this article,we compare the stimulatory effects of nuclease-induced double-strand breaks (DSBs) on homologous and nonhomologous recombination for molecules transfected by CPP and by electroporation. Although electroporation yielded fewer transfectants, both nonhomologous and homologous recombination were stimulated by nuclease-induced DSBs to a greater degree than with CPP. Ionizing radiation is an-effective agent for inducing DNA strand breaks, but previous studies using CPP generally showed little or no stimulation of homologous recombination among plasmids damaged with ionizing radiation. By contrast, we found clear dose-dependent enhancement of recombination with irradiated plasmids transfected using electroporation. Thus, electroporation provides a higher signal-to-noise ratio for transfection-based studies of damage-induced recombination, possibly reflecting less nonspecific damage to plasmid DNA during transfection of mammalian cells. C1 Univ New Mexico, Sch Med, Dept Mol Genet & Microbiol, Albuquerque, NM 87131 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. FU NCI NIH HHS [CA54079]; PHS HHS [R01 55019] NR 65 TC 9 Z9 9 U1 0 U2 2 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 1073-6085 J9 MOL BIOTECHNOL JI Mol. Biotechnol. PD OCT PY 1998 VL 10 IS 2 BP 93 EP 101 DI 10.1007/BF02760857 PG 9 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 134MM UT WOS:000076746900001 PM 9819809 ER PT J AU Aars, J Ims, RA Liu, HP Mulvey, M Smith, MH AF Aars, J Ims, RA Liu, HP Mulvey, M Smith, MH TI Bank voles in linear habitats show restricted gene flow as revealed by mitochondrial DNA (mtDNA) SO MOLECULAR ECOLOGY LA English DT Article DE bank vole; gene flow; landscape ecology; linear habitats; movement; mtDNA ID CLETHRIONOMYS-GLAREOLUS; POPULATION; CORRIDORS; PATTERNS; ORIGIN; CONSERVATION; MOVEMENTS; DISPERSAL; LANDSCAPE; DYNAMICS AB Genetic structure of bank vole populations in linear river bank habitat in southeast Norway was determined from analyses of DNA sequences for the mitochondrial D-loop. Animals were sampled at sites separated by 1 km, along two forested river banks separated by approximate to 100 m of open water. Twenty-six distinct haplotypes were found among 120 voles. The voles showed significant deviation from panmixis on both sides of the river. Animals from the same site or from sites 1 km apart were more likely to share haplotypes than animals 2 km apart or more. Common haplotypes were widespread on both river banks, and had a wider distribution than relatively rare haplotypes. Some rare haplotypes were found on both banks, but most were restricted to a single bank. The results suggest that short-term gene flow may be restricted for female bank voles in linear habitats. Female territorial behaviour may vary with habitat geometry. In the linear habitat described here, females defend only two territorial borders and may effectively limit female dispersal. Results were compared to a previous study of bank voles from this region in a two-dimensional habitat. Gene flow in the linear habitat was much more restricted than gene flow in the two-dimensional habitat. Probable mechanisms underlying this difference are discussed. C1 Univ Oslo, Inst Biol, N-0316 Oslo, Norway. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Aars, J (reprint author), Univ Oslo, Inst Biol, Box 1050 Blindern, N-0316 Oslo, Norway. EM jon.aars@bin.uio.no NR 33 TC 41 Z9 44 U1 1 U2 1 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0962-1083 J9 MOL ECOL JI Mol. Ecol. PD OCT PY 1998 VL 7 IS 10 BP 1383 EP 1389 DI 10.1046/j.1365-294x.1998.00487.x PG 7 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 127JF UT WOS:000076346800012 PM 9787447 ER PT J AU Scott, D AF Scott, D TI Naturalist at large: A breeding congress SO NATURAL HISTORY LA English DT Article C1 Savannah River Ecol Lab, Aiken, SC 29801 USA. RP Scott, D (reprint author), Savannah River Ecol Lab, Aiken, SC 29801 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU AMER MUSEUM NAT HISTORY PI NEW YORK PA ATTN: LIBRARY SERIALS UNIT CENTRAL PK WEST AT 79TH ST, NEW YORK, NY 10024-5192 USA SN 0028-0712 J9 NAT HIST JI Nat. Hist. PD OCT PY 1998 VL 107 IS 8 BP 26 EP 28 PG 3 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 121WA UT WOS:000076037600009 ER PT J AU Huang, SR Li, BM Gray, MD Oshima, J Mian, SI Campisi, J AF Huang, SR Li, BM Gray, MD Oshima, J Mian, SI Campisi, J TI The premature ageing syndrome protein, WRN, is a 3 '-> 5 ' exonuclease SO NATURE GENETICS LA English DT Letter ID WERNER-SYNDROME; CELLS; HELICASE; INVITRO; DISEASE C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Cell & Mol Biol, Berkeley, CA 94720 USA. Univ Washington, Dept Pathol, Seattle, WA 98195 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Radiat Biol, Berkeley, CA 94720 USA. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Cell & Mol Biol, Berkeley, CA 94720 USA. FU NIA NIH HHS [AG11658, AG05776, AG14446, F32 AG005776, R01 AG011658] NR 14 TC 316 Z9 319 U1 0 U2 9 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1061-4036 J9 NAT GENET JI Nature Genet. PD OCT PY 1998 VL 20 IS 2 BP 114 EP 116 DI 10.1038/2410 PG 3 WC Genetics & Heredity SC Genetics & Heredity GA 125HL UT WOS:000076231300009 PM 9771700 ER PT J AU Pinkel, D Seagraves, R Sudar, D Clark, S Poole, I Kowbel, D Collins, C Kuo, WL Chen, C Zhai, Y Dairkee, SH Ljung, BM Gray, JW Albertson, DG AF Pinkel, D Seagraves, R Sudar, D Clark, S Poole, I Kowbel, D Collins, C Kuo, WL Chen, C Zhai, Y Dairkee, SH Ljung, BM Gray, JW Albertson, DG TI High resolution analysis of DNA copy number variation using comparative genomic hybridization to microarrays SO NATURE GENETICS LA English DT Article ID HUMAN BREAST-CANCER; HUMAN UROEPITHELIAL CELLS; IN-SITU HYBRIDIZATION; INDEPENDENT AMPLIFICATION; CHROMOSOME 20Q13; REGIONS; LINES; PATTERNS; TUMORS; MDM2 AB Gene dosage variations occur in many diseases. In cancer, deletions and copy number increases contribute to alterations in the expression of tumour-suppressor genes and oncogenes, respectively. Developmental abnormalities, such as Down, Prader Willi, Angelman and Cri du Chat syndromes, result from gain or loss of one copy of a chromosome or chromosomal region. Thus, detection and mapping of copy number abnormalities provide an approach for associating aberrations with disease phenotype and for localizing critical genes. Comparative genomic hybridization(1) (CGH) was developed for genome-wide analysis of DNA sequence copy number in a single experiment. In CGH, differentially labelled total genomic DNA from a 'test' and a 'reference' cell population are cohybridized to normal metaphase chromosomes, using blocking DNA to suppress signals from repetitive sequences. The resulting ratio of the fluorescence intensities at a location on the 'cytogenetic map', provided by the chromosomes, is approximately proportional to the ratio of the copy numbers of the corresponding DNA sequences in the test and reference genomes, CGH has been broadly applied to human and mouse malignancies. The use of metaphase chromosomes, however, limits detection of events involving small regions (of less than 20 Mb) of the genome, resolution of closely spaced aberrations and linking ratio changes to genomic/genetic markers. Therefore, more laborious locus-by-locus techniques have been required for higher resolution studies(2-5). Hybridization to an array of mapped sequences instead of metaphase chromosomes could overcome the limitations of conventional CGH (ref, 6) if adequate performance could be achieved. Copy number would be related to the test/reference fluorescence ratio on the array targets, and genomic resolution could be determined by the map distance between the targets, or by the length of the cloned DNA segments. We describe here our implementation of array CGH, We demonstrate its ability to measure copy number with high precision in the human genome, and to analyse clinical specimens by obtaining new information on chromosome 20 aberrations in breast cancer. C1 Univ Calif San Francisco, Ctr Canc, Canc Genet Program, San Francisco, CA 94143 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Vysis Inc, Downers Grove, IL USA. Calif Pacific Med Ctr, Geraldine Brush Canc Res Inst, San Francisco, CA 94115 USA. Univ Calif San Francisco, Dept Pathol, San Francisco, CA 94143 USA. MRC, Mol Biol Lab, Cambridge CB2 2QH, England. RP Pinkel, D (reprint author), Univ Calif San Francisco, Ctr Canc, Canc Genet Program, Box 0808, San Francisco, CA 94143 USA. RI Dairkee, Shanaz/D-6743-2012; OI Sudar, Damir/0000-0002-2510-7272 FU NCI NIH HHS [CA 45919, P50 CA 58207]; NICHD NIH HHS [HD 17665] NR 31 TC 1468 Z9 1528 U1 10 U2 81 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1061-4036 J9 NAT GENET JI Nature Genet. PD OCT PY 1998 VL 20 IS 2 BP 207 EP 211 DI 10.1038/2524 PG 5 WC Genetics & Heredity SC Genetics & Heredity GA 125HL UT WOS:000076231300027 PM 9771718 ER PT J AU Lacy, DB Tepp, W Cohen, AC DasGupta, BR Stevens, RC AF Lacy, DB Tepp, W Cohen, AC DasGupta, BR Stevens, RC TI Crystal structure of botulinum neuro-toxin type A and implications for toxicity SO NATURE STRUCTURAL BIOLOGY LA English DT Article ID X-RAY; TETANUS NEUROTOXIN; RESOLUTION; DOMAIN; IDENTIFICATION; PROTEOLYSIS; LOCATION; FRAGMENT; BINDING; ERRORS AB Botulinum neurotoxin type A (BoNT/A) is the potent disease agent in botulism, a potential biological weapon and an effective therapeutic drug for involuntary muscle disorders. The crystal structure of the entire 1,285 amino acid di-chain neurotoxin was determined at 3.3 Angstrom resolution. The structure reveals that the translocation domain contains a central pair of alpha-helices 105 Angstrom long and a similar to 50 residue loop or belt that wraps around the catalytic domain. This belt partially occludes a large channel leading to a buried, negative active site - a feature that calls for radically different inhibitor design strategies from those currently used. The fold of the translocation domain suggests a mechanism of pore formation different from other toxins. Lastly, the toxin appears as a hybrid of varied structural motifs and suggests a modular assembly of functional subunits to yield pathogenesis. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Earnest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Wisconsin, Dept Food Microbiol & Toxicol, Madison, WI 53706 USA. RP Stevens, RC (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Stevens, Raymond/K-7272-2015 OI Stevens, Raymond/0000-0002-4522-8725 NR 37 TC 492 Z9 505 U1 7 U2 36 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1072-8368 J9 NAT STRUCT BIOL JI Nat. Struct. Biol. PD OCT PY 1998 VL 5 IS 10 BP 898 EP 902 DI 10.1038/2338 PG 5 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 126QC UT WOS:000076303800016 PM 9783750 ER PT J AU Peterfreund, N Baram, Y AF Peterfreund, N Baram, Y TI Trajectory control of convergent networks SO NEURAL PROCESSING LETTERS LA English DT Article DE dynamical neural networks; feedback control; finite time convergence; Lasalle theorem; learning; trajectory control ID NEURAL NETWORKS AB We present a class of feedback control functions which increase the convergence rates of nonlinear dynamical systems. A simple sign function is used to obtain convergence in finite time. We describe a trajectory learning procedure which preserves the convergence property of the system. Based on the proposed feedback, we developed a new neural network model which converges in finite time. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Technion Israel Inst Technol, Dept Comp Sci, IL-32000 Haifa, Israel. NR 7 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1370-4621 J9 NEURAL PROCESS LETT JI Neural Process. Lett. PD OCT PY 1998 VL 8 IS 2 BP 99 EP 106 DI 10.1023/A:1009690109549 PG 8 WC Computer Science, Artificial Intelligence; Neurosciences SC Computer Science; Neurosciences & Neurology GA 131BU UT WOS:000076556500001 ER PT J AU Jagust, WJ Haan, MN Reed, BR Eberling, JL AF Jagust, WJ Haan, MN Reed, BR Eberling, JL TI Brain perfusion imaging predicts survival in Alzheimer's disease SO NEUROLOGY LA English DT Article ID POSITRON EMISSION TOMOGRAPHY; COGNITIVE DECLINE; SENILE DEMENTIA; COMPUTED-TOMOGRAPHY; BLOOD-FLOW; ONSET; MORTALITY; INSTITUTIONALIZATION; PATTERNS; DEATH AB Background: The variability of disease course in patients diagnosed with AD makes prediction of survival difficult, despite the identification of numerous predictors to date. This study evaluated the predictive utility of measurements of regional cerebral blood flow (rCBF) obtained with SPECT in a group of AD patients. Methods: Fifty AD patients were studied with SPECT and followed longitudinally. SPECT measures of relative rCBF were calculated by measuring radioactivity densities in dorsolateral frontal, orbitofrontal, temporal, and parietal cortex normalized to occipital cortical radioactivity density. Subjects were classified into three tertiles of rCBF ratios for each region. These rcBF ratios were used as predictors of survival in life-table and proportional hazard models to predict survival. Results: Right parietal rCBF was a significant predictor of survival in the life-table analysis, with subjects in the lowest tertile having shortest survivals. No other brain region was a significant predictor of survival. In a proportional hazards model when a variety of other potential predictors were accounted for, right parietal rCBF ratio remained a significant predictor. Conclusions: These results demonstrate that brain perfusion in the right parietal lobe is a significant predictor of survival in patients with AD even when other predictors are taken into consideration. This suggests that SPECT perfusion imaging may provide additional useful information on disease prognosis in AD. C1 Lawrence Berkeley Natl Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Neurol, Davis, CA USA. Univ Calif Davis, Dept Epidemiol & Prevent Med, Davis, CA USA. RP Jagust, WJ (reprint author), Lawrence Berkeley Natl Lab, Ctr Funct Imaging, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NIA NIH HHS [AG07793, R03 AG033751, AG10129]; NIDDK NIH HHS [R01 DK060753] NR 31 TC 32 Z9 33 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0028-3878 J9 NEUROLOGY JI Neurology PD OCT PY 1998 VL 51 IS 4 BP 1009 EP 1013 PG 5 WC Clinical Neurology SC Neurosciences & Neurology GA 128HC UT WOS:000076399100019 PM 9781521 ER PT J AU Sanchez, R Jimenez, JA Garcia, L AF Sanchez, R Jimenez, JA Garcia, L TI Kinetic effects on ideal ballooning stability of the TJ-II heliac device SO NUCLEAR FUSION LA English DT Article ID TOROIDAL PLASMA; MODE; EQUATIONS; FREQUENCY; CONFIGURATIONS; INSTABILITIES AB Kinetic corrections to a previous ideal MHD ballooning stability study of the TJ-II heliac standard configuration are numerically calculated using a criterion derived from the gyrokinetic Maxwell equations for modes with perpendicular wavelengths on the scale of the ion gyroradius in a general magnetic geometry. In this criterion, finite ion gyroradius and trapped particle effects are retained at first order. The existence of temperature gradients and different ion and electron temperatures are accounted for. The relevant kinetic regime for TJ-II is found to be the intermediate frequency regime, with omega(bi), omega(ti) < gamma < omega(be), omega(te) across all the relevant region whenever electron cyclotron resonance heating (ECRH) plasmas are considered. Therefore, only trapped electrons are included in the calculations. The threshold poloidal wavenumber m(u) for diamagnetic stabilization of unstable ballooning modes is obtained, and a reduction of about 30% of the instability region radial width has been found. The trapped electron contribution to the growth rate is shown to be destabilizing for all modes with poloidal wavenumber below this threshold and is evaluated perturbatively, shoeing that an important part of it is due to those electrons trapped in the ripple of the magnetic field. C1 Univ Carlos 3, Escuela Politecn Super, Dept Fis, Madrid, Spain. CIEMAT, Asoc Euratom, Div Fus, E-28040 Madrid, Spain. RP Sanchez, R (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM sanchezr@ornl.gov RI Sanchez, Raul/C-2328-2008; Garcia, Luis/A-5344-2015; Jimenez, Juan/A-5245-2017 OI Garcia, Luis/0000-0002-0492-7466; Jimenez, Juan/0000-0003-3453-2470 NR 21 TC 3 Z9 3 U1 0 U2 0 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 OCT PY 1998 VL 38 IS 10 BP 1511 EP 1521 DI 10.1088/0029-5515/38/10/308 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 136WU UT WOS:000076882700009 ER PT J AU Pollaine, SM Eimerl, D AF Pollaine, SM Eimerl, D TI Modal analysis of power imbalance and pointing errors for direct drive and tetrahedral hohlraums SO NUCLEAR FUSION LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; LASER; FUSION; NOVA AB This article extends the work of Skupsky and Lee (SKUPSKY, S., LEE, K., Appl. Phys. 54 (1983) 3662) and Murakami et al. (MURAKAMI, M., et al., J. Appl. Phys. 74 (1993) 802) in presenting analytic formulas that predict the laser flux asymmetry, in various inertial confinement fusion (ICF) targets from low order modes, due to beam geometry, variations in beam power and beam pointing errors. The variance per I mode a: is given for both direct drive and tetrahedral hohlraums, as a function of mode number, the beam geometry, and the pointing and power balance errors. For the National Ignition Facility (NIF), a proposed 1.8 MJ laser, the flux asymmetry on a direct drive capsule is dominated by power balance errors in modes 1 and 2. For the Omega, a 30 kJ laser at the Laboratory for Laser Energetics at the University of Rochester, the flux asymmetry on a direct drive capsule is dominated by pointing errors in modes 1 to 5. The flux asymmetry on a tetrahedral indirect drive target is dominated by the Y-3,Y-2 mode resulting from the laser entrance holes. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Pollaine, SM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM pollaine@llnl.gov NR 20 TC 3 Z9 3 U1 2 U2 3 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD OCT PY 1998 VL 38 IS 10 BP 1523 EP 1530 DI 10.1088/0029-5515/38/10/309 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 136WU UT WOS:000076882700010 ER PT J AU D'Ippolito, DA Myra, JR Rogers, JH Hill, KW Hosea, JC Majeski, R Schilling, G Wilson, JR Hanson, GR England, AC Wilgen, JB AF D'Ippolito, DA Myra, JR Rogers, JH Hill, KW Hosea, JC Majeski, R Schilling, G Wilson, JR Hanson, GR England, AC Wilgen, JB TI Analysis of rf sheath interactions in TFTR SO NUCLEAR FUSION LA English DT Article ID ION-CYCLOTRON RANGE; SCRAPE-OFF LAYER; ICRF ANTENNAS; IMPURITY PRODUCTION; PLASMA BOUNDARY; WAVES; TEXTOR; MODE; JET; FREQUENCIES AB New theoretical and experimental tools are applied to the analysis of ICRF antenna-edge plasma interactions in the TFTR tokamak. A new numerical method for computing the three dimensional (3-D) of sheath voltage distribution is used, and the quantitative predictions of rf sheath theory are compared with measurements of the edge density profile obtained by microwave reflectometry and with titanium impurity concentration data. It is shown that the local density depletion at the antenna is consistent with density pump-out by strong E x B convection into the Faraday screen (FS). Modelling of the FS impurity influx shows that the calculated titanium impurity concentration based on this direct influx agrees with the measured concentration for ii phasing. It is also shown that screening of impurity neutrals by ionization in the SOL is a large effect and increases with rf power. At high power over many shots, a fraction of the metal impurities migrates around the machine and is deposited on the limiters, providing a secondary source of titanium. The data show that the central titanium concentration is strongly dependent on antenna phasing. Possible explanations for this phasing dependence are discussed. C1 Lodestar Res Corp, Boulder, CO 80301 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP D'Ippolito, DA (reprint author), Lodestar Res Corp, Boulder, CO 80301 USA. NR 37 TC 45 Z9 45 U1 0 U2 1 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD OCT PY 1998 VL 38 IS 10 BP 1543 EP 1563 DI 10.1088/0029-5515/38/10/311 PG 21 WC Physics, Fluids & Plasmas SC Physics GA 136WU UT WOS:000076882700012 ER PT J AU Yavorskij, VA Edenstrasser, JW Goloborod'ko, VY Reznik, SN Zweben, SJ AF Yavorskij, VA Edenstrasser, JW Goloborod'ko, VY Reznik, SN Zweben, SJ TI Fokker-Planck modelling of delayed loss of charged fusion products in TFTR SO NUCLEAR FUSION LA English DT Article ID ALPHA-PARTICLES; TRANSPORT PROCESSES; DT EXPERIMENTS; TEST REACTOR; TOKAMAK; DIFFUSION; WALL; IONS AB The results of a Fokker-Planck simulation of the ripple induced loss of charged fusion products in TFTR are presented. It is shown that the main features of the measured 'delayed loss' of partially thermalized fusion products (FPs), such as the differences between deuterium-deuterium (DD) and deuterium-tritium (DT) discharges and the plasma current and major radius dependences, are in satisfactory agreement with the classical collisional ripple transport mechanism. The inclusion of an inward shift of the vacuum flux surfaces turns out to be necessary for an adequate and consistent explanation of the origin of the partially thermalized fusion product loss to the bottom of TFTR. C1 Inst Nucl Res, Kiev, Ukraine. Univ Innsbruck, Inst Theoret Phys, A-6020 Innsbruck, Austria. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. RP Yavorskij, VA (reprint author), Inst Nucl Res, Kiev, Ukraine. EM interdep@kinr.kiev.ua; johann.edenstrasser@uibk.ac.at NR 28 TC 16 Z9 16 U1 0 U2 2 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD OCT PY 1998 VL 38 IS 10 BP 1565 EP 1576 DI 10.1088/0029-5515/38/10/312 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 136WU UT WOS:000076882700013 ER PT J AU Khokonov, MK Carrigan, RA AF Khokonov, MK Carrigan, RA TI The relationship of channeling radiation to Thomson scattering and the relative efficiency of X-ray production by intense electron beams SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3rd International Symposium on Radiation from Relativistic Electrons in Periodic Structures (RREPS 97) CY SEP, 1997 CL NUCLEAR PHYSICS INST, TOMSK POLYTECHN UNIV, TOMSK, RUSSIA HO NUCLEAR PHYSICS INST, TOMSK POLYTECHN UNIV ID ELECTROMAGNETIC-RADIATION; PARTICLES; PULSES; GENERATION AB Laser X-ray sources (LXS) based on Thomson backscattering of relativistic electrons by intense laser beams are compared with channeling radiation in oriented crystals. It is shown, that theories of these two types of radiation are very similar to each other but channeling radiation turns out to represent a more general case. Recent experimental results have been analyzed in detail. The advantages and the problems of both types of X-ray sources have been studied. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Kabardino Balkar State Univ, Dept Phys, Nalchik 360004, Russia. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Khokonov, MK (reprint author), Kabardino Balkar State Univ, Dept Phys, Nalchik 360004, Russia. OI Khokonov, Murat/0000-0002-6147-7879 NR 41 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD OCT PY 1998 VL 145 IS 1-2 BP 133 EP 141 DI 10.1016/S0168-583X(98)00285-7 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 132TX UT WOS:000076647100022 ER PT J AU Hernandez, AH Rosales, CS Ortiz, ME Lomeli, ERC del Campo, JG Shapira, D AF Hernandez, AH Rosales, CS Ortiz, ME Lomeli, ERC del Campo, JG Shapira, D TI Proton resonance reactions using thick targets in inverse kinematics SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article AB A technique to study proton resonance reactions using heavy ion beams has been tested with (13)C beams on a 20 mu m polypropylene target. Continuous target motion is maintained to avoid hydrogen loss due to damage by the heavy ion beams and high quality excitation functions can be obtained in a single exposure. This technique can be very valuable for studies with radioactive beams. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 010000, DF, Mexico. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN USA. RP Lomeli, ERC (reprint author), Univ Nacl Autonoma Mexico, Inst Fis, Ap Po 20 364 Del Alvaro Obregon, Mexico City 010000, DF, Mexico. EM chavez@fenix.ifisicacu.unam.mx NR 8 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD OCT PY 1998 VL 143 IS 4 BP 569 EP 574 DI 10.1016/S0168-583X(98)00386-3 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 129GW UT WOS:000076456300015 ER PT J AU Guhlke, S Schaffland, A Zamora, PO Sartor, J Diekmann, D Bender, H Knapp, FF Biersack, HJ AF Guhlke, S Schaffland, A Zamora, PO Sartor, J Diekmann, D Bender, H Knapp, FF Biersack, HJ TI Re-188- and Tc-99m-MAG(3) as prosthetic groups for labeling amines and peptides: Approaches with pre- and postconjugate labeling SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE rhenium-188; technetium-99m; MAG(3) peptides; RC-160; MAG(3)-RC-160; somatostatin ID SOMATOSTATIN ANALOG RC-160; RECEPTOR SCINTIGRAPHY; MONOCLONAL-ANTIBODIES; BIOLOGICAL EVALUATION; CANCER XENOGRAFTS; NUCLEAR-MEDICINE; MAG3 CHELATE; IN-VITRO; BIODISTRIBUTION; TC-99M AB Either radiolabeled Tc-99m or Re-188-labeled MAG(3)-4 -nitrophenylester or unlabeled Bz-MAG(3)-4-nitrophenylester was reacted with amines and peptides to follow a pre- or a postconjugate radiolabeling route, respectively. The model compounds were N'-t-butyloxycarbonyl-1,6-diaminohexane (DH-Boc) and a Lys-protected derivative of the somatostatin analog RC-160 (cyclic D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH2). In the case of labeling DH-Boc, both the preconjugate labeling and the postconjugate labeling were found by using analytical HPLC to provide identical radiolabeled compounds regardless whether Re-188 or Tc-99m was used. The results are supported by infrared and mass-spectral data obtained from compounds synthesized using stable rhenium, The Re-188- or Tc-99m-MAG(3)-RC-160 somatostatin analog were synthesized following the preconjugate labeling route and subsequent removal of the protecting group. Biodistributions of Re-188, and Tc-99m-MAG(3)-RC-160 were evaluated in normal and tumor bearing mice, and were similar to those of radioiodinated I-131-RC-160. All radiolabeled analogs of RC-160 were rapidly cleared from the blood and were excreted through the hepatobiliary system with very little normal organ uptake. The tumor uptake (PC-3, human prostate adenocarcinoma) of systemically administered Re-188-MAG(3)-RC160 was very low, and it reached only 0.28% injected dose/g (%IDg) at 24 h postinjection, similar to what was obtained with I-131-RC-160. Intratumor injections resulted in significant tumor retentions (9.3% ID/g at 24 h), NUCL (C) 1998 Elsevier Science Inc. C1 Univ Bonn, Klin Nukl Med, D-53127 Bonn, Germany. Rho Med Inc, Albuquerque, NM USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Guhlke, S (reprint author), Univ Bonn, Klin Nukl Med, Sigmund Freud Str 25, D-53127 Bonn, Germany. NR 35 TC 50 Z9 55 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD OCT PY 1998 VL 25 IS 7 BP 621 EP 631 DI 10.1016/S0969-8051(98)00025-0 PG 11 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 118RH UT WOS:000075853400006 PM 9804043 ER PT J AU Titarenko, YE Shvedov, OV Igumnov, MM Karpikhin, EI Batyaev, VF Lopatkin, AV Volk, VI Vakhrushin, AY Shepelkov, SV Mashnik, SG Gabriel, TA AF Titarenko, YE Shvedov, OV Igumnov, MM Karpikhin, EI Batyaev, VF Lopatkin, AV Volk, VI Vakhrushin, AY Shepelkov, SV Mashnik, SG Gabriel, TA TI Experimental determination and simulation of the reactivity effects and reaction rate sensitivity to different ranges of neutron energy in homogeneous heavy water solutions of thorium SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article AB The experimental and simulated results of reactivity effects and reaction rate sensitivity to different ranges of neutron energy in heavy water solutions of thorium nitrate are reported. The experiments were carried out at the MAKET critical plant at the institute for Theoretical and Experimental Physics. The reactivity effects were measured by a critical experimental method using the experimental dependence of lattice reactivity variations as a function of heavy water levels in the core tank. The reaction Fates and the functionals were measured in the experimental samples of Al-27, Cu-natur, and Th-232 and of a many-composite Al + Mn-55 + Cu-natur + Au-197 + Lu-natur alloy The experimental samples were measured using a Canberra comanufactured spectrometer (a GC-2518 Ge detector, a 1510 module, and a 1510 plate with software to emulate a multichannel analyzer on an IBM personal computer). The experimental run yielded macrodistribution of reaction rates R-(n,R- gamma)(63Cu) in the lattice, the reactivity effects induced by different thorium nitrate concentrations in the heavy water solution within the volume of the experimental setup, the reactivity effects induced by different heights of filling the experimental tank with the thorium nitrate solution, distribution of reaction rates R-(n,R- gamma)(63Cu), R-(n,R- gamma)(55Mn), R-(n,R- gamma)(197Au), R-(n,R- gamma)(176Lu), R-(n,R- alpha)(27Al), and R-(n,R- gamma)(232Th) within the experimental volume, and distributions of the functional sigma((n, alpha))(27Al)/sigma((n, gamma))(232Th) within the experimental volume. All of the experimental data were simulated by the MCU code and partly by the TRIFON-TREC code. Therefore, it is possible to validate the applicability of the codes for simulating blankets of subcritical accelerator-driven facilities with independent circulation of a heavy water solution of thorium such that U-233 buildup to replace the transmuted Pu-239 can be studied. The results of the experiments and simulation are tabulated and displayed as plots. C1 Inst Theoret & Expt Phys, Moscow 117259, Russia. Res Dev Inst Power Energy, Moscow 101000, Russia. VNIINM, Inst Neorgan Mat, Moscow 123060, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Joint Inst Nucl Res Dubna, Bogoliubov Lab Theoret Phys, Dubna 141980, Russia. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Titarenko, YE (reprint author), Inst Theoret & Expt Phys, Moscow 117259, Russia. NR 19 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 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD OCT PY 1998 VL 130 IS 2 BP 165 EP 180 PG 16 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 130NM UT WOS:000076526200001 ER PT J AU Lewis, EE Palmiotti, G AF Lewis, EE Palmiotti, G TI Red-black response matrix acceleration by transformation of interface variables SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID NODAL DIFFUSION; TRANSPORT AB Red-black algorithms for solving response matrix equations in one- and two-dimensional diffusion theory are examined. The definition of the partial currents in terms of the scalar flux and net currents is altered to introduce an acceleration parameter that modifies the values of the response matrix elements while leaving the flux and net current solutions unchanged. The acceleration parameter is selected for response matrices derived analytically for slab geometry and from the variational nodal method for both slab and x-y geometries to minimize the spectral radius of the red-black iteration matrix for homogeneous media. The optimal value is shown to be independent of the mesh spacing in the fine mesh limit and to be a function only of c, the scattering-to-total cross section ratio. The method is then generalized to treat multiregion problems by formulating an approximate expression for the optimum acceleration parameter and demonstrated for a series of benchmark diffusion problems. C1 Northwestern Univ, Dept Mech Engn, Evanston, IL 60208 USA. Argonne Natl Lab, Reactor Anal Div, Argonne, IL 60439 USA. RP Lewis, EE (reprint author), Northwestern Univ, Dept Mech Engn, Evanston, IL 60208 USA. RI Lewis, Elmer/B-7597-2009 NR 15 TC 3 Z9 3 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD OCT PY 1998 VL 130 IS 2 BP 181 EP 193 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 130NM UT WOS:000076526200002 ER PT J AU Yonomoto, T Kukita, Y Schultz, RR AF Yonomoto, T Kukita, Y Schultz, RR TI Heat transfer analysis of the passive residual heat removal system in ROSA/AP600 experiments SO NUCLEAR TECHNOLOGY LA English DT Article DE passive residual heat removal; ROSA/AP600 experiments; natural-circulation heat transfer AB The passive residual heat removal (PRHR) system in the Westinghouse AP600 advanced passive reactor design is a natural-circulation-driven heat exchanger cooled by the water in the in-containment refueling water storage tank (IRWST). During the experiments, which simulated small-break loss-of-coolant accidents in the AP600 reactor using the ROSA-V Large-Scale Test Facility (LSTF), the PRHR system heat removal rates well exceeded the core decay power soon after the actuation of the PRHR. This resulted in continuous cooldown and depressurization of the primary side. The PRHR heat transfer performance in these experiments was analyzed by applying heat transfer correlations available in literature to the PRHR heat exchanger tube bundle. Also, the three-dimensional natural circulation in the IRWST was simulated numerically using the FLUENT code. The total heat transfer rate of the PRHR was predicted within 5% of the measured value. The fluid temperature distribution in the IRWST was also predicted well except that the elevation of the thermally stratified region was underpredicted. The calculated flow pattern in the IRWST suggests that the atypical IRWST geometry in the LSTF may have affected the PRHR heat transfer performance during the experiments only a little. C1 Japan Atom Energy Res Inst, Thermohydraul Safety Engn Lab, Dept Reactor Safety Res, Tokai, Ibaraki 31911, Japan. Nagoya Univ, Dept Energy Engn & Sci, Chikusa Ku, Nagoya, Aichi 4648603, Japan. Idaho Natl Engn & Environm Lab, Dept Nucl Engn, Idaho Falls, ID 83415 USA. RP Yonomoto, T (reprint author), Japan Atom Energy Res Inst, Thermohydraul Safety Engn Lab, Dept Reactor Safety Res, Tokai, Ibaraki 31911, Japan. NR 13 TC 18 Z9 25 U1 0 U2 3 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 OCT PY 1998 VL 124 IS 1 BP 18 EP 30 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 125TT UT WOS:000076253700002 ER PT J AU Tan, ZQ Chen, ZN Ma, WX AF Tan, ZQ Chen, ZN Ma, WX TI The hybrid quark hadron model in pion-nucleus double-charge-exchange reaction SO NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA A-NUCLEI PARTICLES AND FIELDS LA English DT Article ID CURRENTS AB The differential cross-section of the double-charge-exchange (DCX) reaction C-14(pi(+), pi(-))O-14(g.s.) at 164 MeV is calculated in the hybrid quark hadron (HQH) model. The theoretical results are in good agreement with the experimental data. The short-range effects of DCX reaction come mostly from the six-quark cluster contribution. C1 China Ctr Adv Sci & Technol, World Lab, Beijing 100080, Peoples R China. Guangxi Univ, Dept Phys, Nanning 530004, Guangxi, Peoples R China. Acad Sinica, Inst High Energy Phys, Beijing 100039, Peoples R China. RP Tan, ZQ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, MS 70A-3307, Berkeley, CA 94720 USA. NR 24 TC 0 Z9 0 U1 0 U2 0 PU EDITRICE COMPOSITORI BOLOGNA PI BOLOGNA PA VIA STALINGRADO 97/2, I-40128 BOLOGNA, ITALY SN 1124-1861 J9 NUOVO CIMENTO A JI Nuovo Cimento Soc. Ital. Fis. A-Nucl. Part. Fields PD OCT PY 1998 VL 111 IS 10 BP 1119 EP 1129 PG 11 WC Physics, Particles & Fields SC Physics GA 173QQ UT WOS:000078991600003 ER PT J AU Burke, VJ Rathbun, SL Bodie, JR Gibbons, JW AF Burke, VJ Rathbun, SL Bodie, JR Gibbons, JW TI Effect of density on predation rate for turtle nests in a complex landscape SO OIKOS LA English DT Article ID HATCHING SUCCESS; INTERFERENCE; POPULATIONS; SERPENTINA; CHELYDRA; ECOLOGY AB The relationship between the spatial distribution of turtle nest sites and nest predation was investigated in a landscape encompassing a 12-ha freshwater wetland in west-central South Carolina, USA. The goals of the study were to determine if nest predation is a function of nest density, and if two other spatial factors, habitat type and distance of nests from the wetland, influence survival rate. Gravid females of three turtle species (Kinosternon subrubrum, Pseudemys concinna floridana, and Trachemys scripta) inhabiting the wetland were monitored from the time they exited the wetland to nest until they returned from their nesting forays. A total of 145 nests were located during three nesting seasons (1992-1994). Nests were monitored from the day of oviposition until they were deemed to have successfully produced hatchlings or depredation was documented. The three-year mean predation rate was 84.2% (80%, 88%, and 81% for 1992, 1993 and 1994, respectively). Modeling of the point pattern of nest locations suggests that nests were distributed at varying densities and that density changed with habitat type and distance to the wetland. Logistic regressions of predation rates against two crowding indices demonstrate no significant evidence for density-dependent nest predation. Furthermore, autologistic regression provided no evidence indicating that nest survival is dependent on the survivorship of neighboring nests. Logistic regressions of predation rates against habitat type and distance from the marsh of origin suggest that predation rate is not a function of these two spatial characteristics. In summary, no evidence was found that linked predation rate to any of the spatial characteristics of nest distribution that were examined. The lack of density dependent nest predation is contrary to findings from some previous avian and chelonian studies, but supports the findings of other researchers. It is suggested that predation during the current study was either density independent or that any local density effects were masked by an ideal free distribution of turtle nests. Our data support the findings of several researchers that suggest density, as a single factor, is not a generalizable predictor of nest predation probability. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ Georgia, Dept Stat, Athens, GA 30602 USA. Univ Missouri, Div Biol Sci, Columbia, MO 65211 USA. RP Univ Missouri, Sch Nat Resources, Columbia, MO 65211 USA. EM vincent_burke@nbs.gov NR 34 TC 39 Z9 43 U1 4 U2 16 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0030-1299 EI 1600-0706 J9 OIKOS JI Oikos PD OCT PY 1998 VL 83 IS 1 BP 3 EP 11 DI 10.2307/3546540 PG 9 WC Ecology SC Environmental Sciences & Ecology GA 119BX UT WOS:000075876400001 ER PT J AU Unanyan, R Fleischhauer, M Shore, BW Bergmann, K AF Unanyan, R Fleischhauer, M Shore, BW Bergmann, K TI Robust creation and phase-sensitive probing of superposition states via stimulated Raman adiabatic passage (STIRAP) with degenerate dark states SO OPTICS COMMUNICATIONS LA English DT Article ID MULTILEVEL SYSTEMS; POPULATION TRANSFER AB We describe a method for creating an arbitrary coherent superposition of two atomic states in a controlled and robust way by using a sequence of three pulses in a four-state system. The proposed technique is based on the existence of two degenerate dark states (i.e. states having no component of the excited state) and their interaction. The mixing of the dark states can be controlled by changing the relative delay of the pulses, and thus an arbitrary superposition state can be generated. It is shown that the method is robust against small variations of parameters (e.g. the area of the pulses) and is insensitive to radiative decay from the intermediate excited state. A time reversed version of the technique makes possible the determination of phase occurring in a superposition of two atomic states. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Kaiserslautern, Fachbereich Phys, D-67653 Kaiserslautern, Germany. Univ Munich, Sekt Phys, D-80333 Munich, Germany. Armenian Natl Acad Sci, Inst Phys Res, Ashtarak 378410 2, Armenia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Unanyan, R (reprint author), Univ Kaiserslautern, Fachbereich Phys, Postfach 3049, D-67653 Kaiserslautern, Germany. RI Fleischhauer, Michael/G-6716-2011; BERGMANN, KLAAS/D-5543-2011 NR 13 TC 152 Z9 159 U1 1 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD OCT 1 PY 1998 VL 155 IS 1-3 BP 144 EP 154 DI 10.1016/S0030-4018(98)00358-7 PG 11 WC Optics SC Optics GA 127RH UT WOS:000076364000023 ER PT J AU Cong, G Ma, SD AF Cong, G Ma, SD TI Corner enhancement in curvature scale space SO PATTERN RECOGNITION LA English DT Article DE scale space; curvature scale space; curve evolution; corner enhancement; features extraction ID EDGE-DETECTION; PLANE-CURVES; SHAPE; EVOLUTION; DIFFUSION AB Corner detection is very important for pattern recognition, computer vision and other works. However, successfully extracting corners from a planar curve is difficult because we do not know how to select the appropriate scale for the extraction. In this paper, the problem of corner enhancement via the curve scale space is addressed. The main idea of the approach is to deform the original curve (or construct the curve scale space) and the corners on the deformed curve become distinguished from other structures which eases the process of corner detection. Started from the general geometric heat flow (GGHF), we study under what conditions the GGHF satisfies the scale space causality criteria. This is very important because many different evolution approaches, which have regular scale space properties and other specific properties, can then be found from these conditions. The criteria of corner enhancement are also proposed. Having all these constraints, a new curve evolution scheme which can enhance strong corners suppress noise and satisfies the scale space criteria is presented. (C) 1998 Pattern Recognition Society. Published by Elsevier Science Ltd. All rights reserved. C1 Chinese Acad Sci, Inst Automat, Natl Lab Pattern Recognit, Beijing 100080, Peoples R China. RP Cong, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 50E-201, Berkeley, CA 94720 USA. NR 18 TC 4 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0031-3203 J9 PATTERN RECOGN JI Pattern Recognit. PD OCT PY 1998 VL 31 IS 10 BP 1491 EP 1501 DI 10.1016/S0031-3203(98)00003-X PG 11 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 103NM UT WOS:000075162900008 ER PT J AU Allen, EE Lederman, L AF Allen, EE Lederman, L TI Lessons learned - The Teachers Academy for Mathematics and Science SO PHI DELTA KAPPAN LA English DT Article C1 Teachers Acad Math & Sci, Chicago, IL USA. IIT, Chicago, IL 60616 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Allen, EE (reprint author), Univ Washington, Dept Mol Biotechnol, Seattle, WA 98195 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU PHI DELTA KAPPA PI BLOOMINGTON PA 8TH AND UNION P O BOX 789, BLOOMINGTON, IN 47402 USA SN 0031-7217 J9 PHI DELTA KAPPAN JI Phi Delta Kappan PD OCT PY 1998 VL 80 IS 2 BP 158 EP + PG 5 WC Education & Educational Research SC Education & Educational Research GA 126ED UT WOS:000076279200011 ER PT J AU Dao, M Asaro, RJ Sebring, RJ AF Dao, M Asaro, RJ Sebring, RJ TI Interface instability in the bulk processing of 2223 BSCCO powders SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID PLASTIC-DEFORMATION; 2223-BSCCO POWDERS; TEXTURE EVOLUTION; TAPES; COMPOSITES; CRYSTALS; J(C); SUPERCONDUCTORS; MICROHARDNESS; DENSITY AB Interface instability (or "sausaging') has been a major problem in the oxide powder-in-tube tape-rolling process. The fast Fourier transform of core instabilities are first performed to study the rolled tapes and to obtain quantitative information on the wavelengths and magnitudes of the nonuniform profiles. The existing experimental observations are also re-examined and summarized. Treating this problem as the bimaterial interface instability, both bifurcation analysis and finite-element modelling are applied to study the influences of roll-gap geometry, packing fill factor and clad material properties on the instability wavelength and magnitude. Good correlations between theoretical results and experimental observations are found. The critical waveleneth/current core thickness ratio lambda*/d(c) is found to be sensitive to the fill factor only, and insensitive to the reduction/pass ratio, and the core and clad material properties; that is, the relative tape geometry is the single dominating factor that affect the normalized critical wavenumber lambda*/d(c). Consistent with experimental observations, a smaller reduction/pass ratio, a higher initial core porosity, a higher hardening clad material and a larger core fill factor can reduce the normalized instability magnitude Delta v/d(c) (i.e. the instability magnitude/current core thickness ratio) at the same tape reduction strain level. The results suggest that the reason for the much smaller interface variation magnitude with a small reduction/pass ratio (i.e. 5% per pass) compared with a large reduction/pass ratio (i.e. 25% per pass) is not because the small reduction/ pass ratio can eliminate or delay the interface instability initiation; it is, however, most probably caused by the random disruption of the interface by the many rolling steps with critical wavelengths very close to each other between adjacent rolling steps. C1 TransSci Corp, La Jolla, CA 92037 USA. Univ Calif San Diego, Div Struct Engn, La Jolla, CA 92093 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Dao, M (reprint author), TransSci Corp, 7777 Fay Ave,Suite 112, La Jolla, CA 92037 USA. RI Dao, Ming/B-1602-2008 NR 23 TC 0 Z9 0 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD OCT PY 1998 VL 78 IS 4 BP 857 EP 877 PG 21 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 124MF UT WOS:000076185600005 ER PT J AU Neil, GR AF Neil, GR TI Questionable claim SO PHOTONICS SPECTRA LA English DT Letter C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA USA. RP Neil, GR (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU LAURIN PUBL CO INC PI PITTSFIELD PA BERKSHIRE COMMON PO BOX 1146, PITTSFIELD, MA 01202 USA SN 0731-1230 J9 PHOTON SPECTRA JI Photon. Spect. PD OCT PY 1998 VL 32 IS 10 BP 14 EP 15 PG 2 WC Optics SC Optics GA 127UP UT WOS:000076369200004 ER PT J AU Cho, BK DiSalvo, FJ Kim, JS Stewart, GR Bud'ko, SL AF Cho, BK DiSalvo, FJ Kim, JS Stewart, GR Bud'ko, SL TI Intermediate valence behavior of Yb in Yb2Ni12(P,As)(7) SO PHYSICA B LA English DT Article DE Yb2Ni12 (P,As)(7); specific heat; magnetic susceptibility; resistance ID FLUCTUATIONS; RESISTIVITY; HEAT AB Temperature-dependent specific heat, magnetic susceptibility, and resistance measurements have been carried out to study the electronic state of Yb ion in Yb2Ni12(P,As)(7). All the measurements identify a valence fluctuating state for the Yb in both compounds. The electronic contributions to the specific heat, gamma, are enhanced compared to those of the corresponding Yttrium compounds. The gamma is temperature dependent (increasing with lowering temperature) for Yb2Ni12P7 and temperature independent for Yb2Ni12As7. The parameters of valence fluctuation for the Yb ion are calculated from magnetic susceptibility using the ICF model and were found to be T-sf approximate to 68 K, E-ex approximate to 278 K and T-sf approximate to 204 K, E-ex approximate to 1709 K, resulting in the Yb valence of 2.21 and 2.79, for Yb2Ni12(P,As)(7), respectively. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Augsburg, D-8900 Augsburg, Germany. Cornell Univ, Dept Chem, Ithaca, NY 14853 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP Cho, BK (reprint author), Pohang Univ Sci & Technol, Dept Phys, Pohang Ctr Superconduct, Pohang 790784, South Korea. EM chobk@anyon.postech.ac.kr NR 17 TC 8 Z9 8 U1 0 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD OCT PY 1998 VL 253 IS 1-2 BP 40 EP 46 DI 10.1016/S0921-4526(98)00383-4 PG 7 WC Physics, Condensed Matter SC Physics GA 111VA UT WOS:000075457900004 ER PT J AU Aronov, IE Berman, GP Campbell, DK Doolen, GD Dudiy, SV AF Aronov, IE Berman, GP Campbell, DK Doolen, GD Dudiy, SV TI On the crossover of the surface plasmon spectrum from two-dimensional to quasi one-dimensional in a quantum point contact SO PHYSICA B LA English DT Article DE Surface plasmon spectrum; Quantum point contact ID SINGLE-PARTICLE EXCITATIONS; INELASTIC LIGHT-SCATTERING; LAYERED ELECTRON-GAS; CARBON NANOTUBES; CHARGE-DENSITY; SPIN-DENSITY; WIRES; DISPERSION; ELECTRODYNAMICS; TRANSPORT AB Using a Wigner distribution function formalism, the spectrum of the surface plasmons in a two-dimensional quantum point contact of a strip form is investigated. A crossover of the dispersion relation from 2D plasmons to quasi-1D plasmons is analyzed as a function of two dimensionless parameters: k(x)d (where k(x) is the longitudinal wave vector, and d is the width of the contact), and the number of propagating electron modes, N. The velocities of the surface plasmons are calculated. It is shown that in the quasi-ID limit, the spectrum of plasmons is of an acoustic type, and the velocities may greatly exceed the Fermi velocity. When the number of propagating modes N increases, and under the condition k(x)d>>1 (2D limit), the spectrum of plasmons transforms to the square-root type. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Sage Technol Inc, Marietta, GA 30066 USA. Univ Calif Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Natl Acad Sci Ukraine, Inst Radiophys & Elect, UA-310085 Kharkov, Ukraine. RP Berman, GP (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-13,MS B213, Los Alamos, NM 87545 USA. NR 47 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD OCT PY 1998 VL 253 IS 3-4 BP 169 EP 179 DI 10.1016/S0921-4526(98)00406-2 PG 11 WC Physics, Condensed Matter SC Physics GA 118HD UT WOS:000075831600001 ER PT J AU Yang, CY Babcock, SE Goyal, A Paranthaman, M List, FA Norton, DP Kroeger, DM Ichinose, A AF Yang, CY Babcock, SE Goyal, A Paranthaman, M List, FA Norton, DP Kroeger, DM Ichinose, A TI Microstructure of electron-beam-evaporated epitaxial yttria-stabilized zirconia/CeO2 bilayers on biaxially textured Ni tape SO PHYSICA C LA English DT Article DE coated conductors; RABiTS (TM); biaxial texture; buffer layers; YSZ; CeO2; YBa2Cu3O7-delta ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES AB Transmission and scanning electron microscopy, atomic force microscopy, X-ray pole figure analysis and Auger electron spectroscopy were used to characterize the microstructure and surface topography of epitaxial yttria-stabilized zirconia (YSZ) and CeO2 thin films deposited by electron beam evaporation on rolling-assisted biaxially textured Ni substrates (RABiTS(TM)). The as-deposited YSZ layer is composed of highly crystallographically aligned, slab-shaped columnar grains with sharply defined, rectangular cross sections and average dimensions of 10 nm by 50 nm by the film thickness. The faces of the YSZ slabs lie on the {110} planes that contain the surface normal. Their caps are roof-shaped with a peak-to-valley height of about 10 nm and a RMS roughness, measured by atomic force microscopy, of 1.3 nm. The resultant surface morphology is rough, but shows a regular, cross-hatched pattern on the length scale of about 10 nm. The length scale and crystallographic directionality of the YSZ microstructure is retained when YBa2Cu3O7-delta is pulsed laser deposited on it, but the YSZ columns appear to have sintered into a less angular, more distinctly porous microstructure. The CeO2 layer also is columnar, but appears to be denser, with a flatter, less directional surface topography. Auger sputtering-depth profiling experiments revealed that the compositions of both films are constant through the film thickness and that interdiffusion along the surface normal is not extensive. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. Univ Wisconsin, Engn & Appl Superconduct Ctr, Madison, WI 53706 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Cent Res Inst Elect Power Ind, Tokyo 201, Japan. RP Yang, CY (reprint author), Univ Wisconsin, Dept Mat Sci & Engn, 1509 Univ Ave, Madison, WI 53706 USA. RI Paranthaman, Mariappan/N-3866-2015 OI Paranthaman, Mariappan/0000-0003-3009-8531 NR 11 TC 42 Z9 42 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD OCT 1 PY 1998 VL 307 IS 1-2 BP 87 EP 98 DI 10.1016/S0921-4534(98)00419-5 PG 12 WC Physics, Applied SC Physics GA 135ER UT WOS:000076788400012 ER PT J AU Kolakowska, A Pindzola, MS Robicheaux, F Schultz, DR Wells, JC AF Kolakowska, A Pindzola, MS Robicheaux, F Schultz, DR Wells, JC TI Excitation and charge transfer in proton-hydrogen collisions SO PHYSICAL REVIEW A LA English DT Article ID DEPENDENT SCHRODINGER-EQUATION; ION-ATOM COLLISIONS; H+-H COLLISIONS; ELECTRON-CAPTURE; CROSS-SECTIONS; NUMERICAL-SOLUTION; H(2S) FORMATION; HARTREE-FOCK; IONIZATION; ANTIPROTONS AB Excitation and charge transfer cross sections for collisions of protons with hydrogen are calculated; by direct solution of the time-dependent Schrodinger equation on a three-dimensional Cartesian lattice. The 2s,2p, 3s, 3p, and 3d excitation cross sections and the Is, 2s, 2p, 3s, 3p, and 3d charge transfer cross sections from the Is ground state at 10-, 40-, and 100-keV incident proton energy are found by projecting a time-evolved wave function onto the lattice target states of hydrogen. Excitation processes are calculated in the rest frame of the hydrogen atom, while capture processes are calculated in the rest frame of the proton. The computed excitation and charge transfer cross sections are in good agreement with recent experiments and other theoretical results based on coupled-channels methods, [S1050-2947(98)03210-7]. C1 Auburn Univ, Dept Phys, Auburn, AL 36849 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Ctr Computat Sci, Oak Ridge, TN 37831 USA. RP Kolakowska, A (reprint author), Auburn Univ, Dept Phys, Auburn, AL 36849 USA. RI Wells, Jack/D-3675-2016; Robicheaux, Francis/F-4343-2014 OI Wells, Jack/0000-0002-5083-3030; Robicheaux, Francis/0000-0002-8054-6040 NR 34 TC 48 Z9 49 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1998 VL 58 IS 4 BP 2872 EP 2880 DI 10.1103/PhysRevA.58.2872 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 127WQ UT WOS:000076373900039 ER PT J AU Isaacs, WA McCurdy, CW Rescigno, TN AF Isaacs, WA McCurdy, CW Rescigno, TN TI Low-energy electron scattering from BCl3 SO PHYSICAL REVIEW A LA English DT Article ID ACCURATE ABINITIO TREATMENT; EFFECTIVE POTENTIAL METHODS; BORON-TRICHLORIDE; CROSS-SECTIONS; VARIATIONAL TREATMENTS; MOLECULE COLLISIONS; EXCITATION; IMPACT; MIXTURES; PLASMA AB Despite the importance of BCl3 in plasmas used for commercial etching processes, no calculations or measurements of elastic low-energy electron scattering from BCl3 have previously appeared in the literature. We therefore present calculations based on the complex Kohn method for elastic electron-BCl3 scattering at incident electron energies below 8 eV. We find a near-zero-energy virtual state and a sharp temporary negative-ion resonance at 0.25 eV, which likely contributes to the large electron attachment cross sections observed in swarm studies. [S1050-2947(98)03410-6]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Phys & Space Technol Directorate, Livermore, CA 94550 USA. RP Isaacs, WA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 34 TC 13 Z9 13 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1998 VL 58 IS 4 BP 2881 EP 2886 DI 10.1103/PhysRevA.58.2881 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 127WQ UT WOS:000076373900040 ER PT J AU Sorensen, AH AF Sorensen, AH TI Ionization of one-electron ions penetrating a target at relativistic energies SO PHYSICAL REVIEW A LA English DT Article ID IMPACT AB It is argued that the cross section for ionization of a hydrogenlike ion penetrating a target at relativistic speed upsilon=beta c saturates already at moderate values of gamma equivalent to 1/root 1-beta(2). This is at variance with results published previously [R. Anholt and U. Becker, Phys. Rev. A 36, 4628 (1987)]. A simple model is developed and shown to yield cross sections in accordance with those of the only two experiments performed so far. [S1050-2947(98)04510-7]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Aarhus, Inst Phys & Astron, DK-8000 Aarhus C, Denmark. RP Sorensen, AH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 13 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 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1998 VL 58 IS 4 BP 2895 EP 2899 DI 10.1103/PhysRevA.58.2895 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 127WQ UT WOS:000076373900042 ER PT J AU Kwiat, PG Weinfurter, H AF Kwiat, PG Weinfurter, H TI Embedded Bell-state analysis SO PHYSICAL REVIEW A LA English DT Article ID SINGLE-PHOTON DETECTORS; QUANTUM; PHASE; TIME; PHOTOMULTIPLIER; INEQUALITY; EFFICIENCY; VIOLATION; SHIFTS; VACUUM AB We discuss a method for distinguishing the four orthogonal Bell states of two entangled particles. Because the scheme relies only on linear optical elements, it should be realizable with current technology. The new feature is that the Bell states must be embedded in a larger Hilbert space. That is, the correlated particles must be entangled in more than one degree of freedom. [S1050-2947(98)50310-1]. C1 Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. Univ Innsbruck, Inst Phys Expt, A-6020 Innsbruck, Austria. RP Los Alamos Natl Lab, Div Phys, P-23,MS-H803, Los Alamos, NM 87545 USA. RI Weinfurter, Harald/F-8225-2015 OI Weinfurter, Harald/0000-0001-6882-3909 NR 31 TC 120 Z9 121 U1 0 U2 9 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 OCT PY 1998 VL 58 IS 4 BP R2623 EP R2626 DI 10.1103/PhysRevA.58.R2623 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 127WQ UT WOS:000076373900001 ER PT J AU Li, YL Nilsen, J Dunn, J Osterheld, AL Ryabtsev, A Churilov, S AF Li, YL Nilsen, J Dunn, J Osterheld, AL Ryabtsev, A Churilov, S TI Wavelengths of the Ni-like 4d S-1(0)-4p P-1(1) x-ray laser line SO PHYSICAL REVIEW A LA English DT Article ID NICKEL-LIKE IONS; BR-VIII; 7.9 NM; TRANSITIONS; GAIN; NB AB We measure the wavelengths of the Ni-like 3d(9) 4d S-1(0)-3d(9) 4p P-1(1) x-ray laser line in several low-Z Ni-like ions ranging from Y (Z=39) to Cd (Z=48). These wavelengths are compared with optimized level calculations using a multiconfiguration Dirac-Fock code. With the help of these results, we identify this line to very high accuracy in nonlasing plasmas from As (Z=33) to Mo (Z=42). Accurate values of these wavelengths are essential for performing plasma imaging and interferometry experiments with multilayer optics that use the x-ray laser to backlight other plasmas.-These results also provide important atomic data that are currently missing about the energy of the 4d S-1(0) level in the Ni I sequence. [S1050-2947(98)50809-8]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Russian Acad Sci, Inst Spect, Troitsk 142092, Moscow Region, Russia. RP Li, YL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 36 TC 34 Z9 34 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1998 VL 58 IS 4 BP R2668 EP R2671 DI 10.1103/PhysRevA.58.R2668 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 127WQ UT WOS:000076373900013 ER PT J AU Hatano, N Nelson, DR AF Hatano, N Nelson, DR TI Non-Hermitian delocalization and eigenfunctions SO PHYSICAL REVIEW B LA English DT Article ID LOCALIZATION; TRANSITION AB Recent Literature on delocalization in non-Hermitian systems has stressed criteria based on sensitivity of eigenvalues to boundary conditions and the existence of a nonzero current. We emphasize here that delocalization also shows up clearly in eigenfunctions, provided one studies the product of left and right eigenfunctions, as required on physical grounds, and not simply the squared modulii of the eigenfunctions themselves. We also discuss the right and left eigenfunctions of the ground state in the delocalized regime and suggest that the behavior of these functions, when considered separately, may be viewed as "intermediate" between localized and delocalized. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Harvard Univ, Lyman Lab Phys, Cambridge, MA 02138 USA. RP Hatano, N (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS-B262, Los Alamos, NM 87545 USA. RI Hatano, Naomichi/K-8176-2012 OI Hatano, Naomichi/0000-0003-0277-1856 NR 24 TC 64 Z9 64 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 OCT 1 PY 1998 VL 58 IS 13 BP 8384 EP 8390 DI 10.1103/PhysRevB.58.8384 PG 7 WC Physics, Condensed Matter SC Physics GA 125HU UT WOS:000076232100044 ER PT J AU Islam, Z Detlefs, C Goldman, AI Bud'ko, SL Canfiield, PC Hili, JP Gibbs, D Vogt, T Zheludev, A AF Islam, Z Detlefs, C Goldman, AI Bud'ko, SL Canfiield, PC Hili, JP Gibbs, D Vogt, T Zheludev, A TI Neutron diffraction and x-ray resonant exchange-scattering studies of the zero-field magnetic structures of TbNi2Ge2 SO PHYSICAL REVIEW B LA English DT Article ID ISING-MODEL; POLARIZATION; TBNI2SI2; CRYSTAL; HOLMIUM; METAL; GE AB The zero-field magnetic structures of the rare-earth intermetallic compound TbNi2Ge2 have been determined using conventional magnetic neutron diffraction and high-resolution x-ray resonant exchange scattering techniques. There are two distinct magnetic phase transitions in this material: one is from the high-temperature paramagnetic state to a long period antiferromagnetic phase at the Neel temperature (T-N=16.8 K), and the other is at a lower temperature (T-t= 9.3 K), where the system locks into a commensurate phase. The structure above T-t is described by a longitudinal, amplitude modulated, sinusoidal wave with propagation vector tau(1) approximate to(000.758+/-0.002) in reciprocal-lattice units (r.l.u.). As the temperature is lowered below T-t, tau(1) locks at (0 0 3/4) and additional magnetic Bragg reflections corresponding to tau(2) =(1/2 1/2 0) and tau(3) = (1/2 1/2 1/2) develop. A weak modulation tau(1)' = (0 0 1/4), related to tau(1) also appears indicating a squaring-up of the low-temperature structure. In this equal moment structure all Tb moments have the saturation value of mu(s) = 9.0 +/- 0.2 mu(B). Both the phases are uniaxial with Tb moments parallel to the (c) over cap axis of the tetragonal unit cell. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Islam, Z (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. EM zahirul@iastate.edu RI Detlefs, Carsten/B-6244-2008; Vogt, Thomas /A-1562-2011 OI Detlefs, Carsten/0000-0003-2573-2286; Vogt, Thomas /0000-0002-4731-2787 NR 40 TC 18 Z9 18 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 OCT 1 PY 1998 VL 58 IS 13 BP 8522 EP 8533 DI 10.1103/PhysRevB.58.8522 PG 12 WC Physics, Condensed Matter SC Physics GA 125HU UT WOS:000076232100062 ER PT J AU Tomala, K Sanchez, JP Vulliet, P Canfield, PC Drzazga, Z Winiarska, A AF Tomala, K Sanchez, JP Vulliet, P Canfield, PC Drzazga, Z Winiarska, A TI Squared-spin-modulated versus spiral-like magnetic structures in GdNi2B2C: A Gd-155 Mossbauer-effect investigation SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTING LUNI2B2C; CRYSTAL-STRUCTURE; NI; DYNI2B2C; ERNI2B2C; LUNIBC; ORDER; FIELD AB Gd-155 Mossbauer spectroscopy has been used to study the magnetic properties of GdNi2B2C. It was shown that below T-R congruent to 14 K this compound orders in a bunched spiral-like magnetic structure with. gadolinium magnetic moments rotating within the (b,c) plane. Between T = 14 K and the Neel temperature of T(N)congruent to 20 K the magnetic structure is of sine-modulated type with gadolinium moments perpendicular to the tetragonal c axis. The observation of high-order harmonics indicates, however, a partial squaring of the sine modulation. C1 Jagiellonian Univ, M Smoluchowski Inst Phys, Krakow, Poland. CEA, Dept Rech Fondamentale Mat Condensee, Grenoble, France. Univ Grenoble 1, Grenoble, France. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Silesian Univ, Inst Phys, Katowice, Poland. RP Tomala, K (reprint author), Jagiellonian Univ, M Smoluchowski Inst Phys, Krakow, Poland. RI Canfield, Paul/H-2698-2014 NR 21 TC 15 Z9 15 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 OCT 1 PY 1998 VL 58 IS 13 BP 8534 EP 8541 DI 10.1103/PhysRevB.58.8534 PG 8 WC Physics, Condensed Matter SC Physics GA 125HU UT WOS:000076232100063 ER PT J AU Michel, RP Chaiken, A Wang, CT Johnson, LE AF Michel, RP Chaiken, A Wang, CT Johnson, LE TI Exchange anisotropy in epitaxial and polycrystalline NiO/NiFe bilayers SO PHYSICAL REVIEW B LA English DT Article ID THIN-FILMS; MAGNETIC-PROPERTIES; UNIAXIAL ANISOTROPY; FE/SI MULTILAYERS; NIO; LAYERS; NIFE; BIAS; DEPENDENCE; INTERFACES AB (001)-oriented NiO/NiFe bilayers were grown on single crystal MgO (001) substrates by ion beam sputtering in order to determine the effect that the crystalline orientation of the NiO antiferromagnetic layer has on the magnetization curve of the NiFe ferromagnetic layer. The simplest model predicts no exchange anisotropy for the (001)-oriented NiO surface, which in its bulk termination is magnetically compensated. Nonetheless exchange anisotropy is present in the epitaxial films, although it is approximately half as large as in polycrystalline films that were grown simultaneously. The surface anisotropy in the epitaxial films is found to contain cubic and unidirectional components, while that in the polycrystalline film is best described by a uniaxial plus unidirectional anisotropy. Experiments indicate that differences in exchange field and coercivity between polycrystalline and epitaxial NiFe/NiO bilayers couples arise due to variations in induced surface anisotropy. Implications of these observations for models of induced exchange anisotropy in NiO/NiFe bilayer couples will be discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Div Mat Sci & Technol, Livermore, CA 94551 USA. Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. RP Michel, RP (reprint author), Seagate Technol, 7801 Comp Ave S, Minneapolis, MN 55435 USA. EM Richard_P_Michel@notes.seagate.com; chaiken@hpl.hp.com NR 46 TC 45 Z9 46 U1 5 U2 13 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD OCT 1 PY 1998 VL 58 IS 13 BP 8566 EP 8573 DI 10.1103/PhysRevB.58.8566 PG 8 WC Physics, Condensed Matter SC Physics GA 125HU UT WOS:000076232100067 ER EF