FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Van Blarigan, P Keller, JO AF Van Blarigan, P Keller, JO TI A hydrogen fuelled internal combustion engine designed for single speed/power operation SO INTERNATIONAL JOURNAL OF HYDROGEN ENERGY LA English DT Article AB Sandia National Laboratory is developing from first principles a hydrogen fuelled internal combustion engine for driving an electrical generator that can be utilized either as a stationary power set or the auxiliary power unit in a hybrid vehicle. The intent is to take advantage of hydrogen's unique fuel characteristics and the constant speed characteristics of generator sets to maximize thermal efficiency while minimizing emissions. The current experiments utilize a flat cylinder combustion chamber shape with two ignition points at high (14: 1) compression ratio. Emissions and indicated thermal efficiency measurements with fuels of hydrogen, natural gas and a blend confirm low emissions and high thermal efficiency. CFD modelling done by Los Alamos National Laboratory (Los Alamos, NM) using their KIVA code is helping to further direct variations in the experimental design space. (C) 1998 International Association for Hydrogen Energy. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Van Blarigan, P (reprint author), Sandia Natl Labs, 7011 East Ave, Livermore, CA 94550 USA. NR 4 TC 21 Z9 21 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-3199 J9 INT J HYDROGEN ENERG JI Int. J. Hydrog. Energy PD JUL PY 1998 VL 23 IS 7 BP 603 EP 609 DI 10.1016/S0360-3199(97)00100-6 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA ZN252 UT WOS:000073627300011 ER PT J AU Frew, DJ Hanchak, SJ Green, ML Forrestal, MJ AF Frew, DJ Hanchak, SJ Green, ML Forrestal, MJ TI Penetration of concrete targets with ogive-nose steel rods SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article DE penetration; ogive-nose steel rods; geometric and material scales ID PROJECTILES AB We conducted depth of penetration experiments in concrete targets with 3.0 caliber radius-head, steel rod projectiles. The concrete targets with 9.5 mm diameter limestone aggregate had a nominal unconfined compressive strength of 58.4 MPa (8.5 ksi) and density 2320 kg/m(3). To explore geometric projectile scales, we conducted two sets of experiments. Projectiles with length-to-diameter ratio of ten were machined from 4340R(c), 45 steel, round stock and had diameters and masses of 20.3 mm, 0.478 kg and 30.5 mm, 1.62 kg. Powder guns launched the projectiles to striking velocities between 400 and 1200 m/s. For these experiments, penetration depth increased as striking velocity increased. When depth of penetration data was divided by a length scale determined from our model, the data collapsed on a single curve. Thus, a single dimensionless penetration depth versus striking velocity prediction was in good agreement with the data at two geometric projectile scales for striking velocities between 400 and 1200 m/s. In addition, we conducted experiments with AerMet 100R(c), 53 steel projectiles and compared depth of penetration and post-test nose erosion data with results from the 4340R(c), 45 steel projectiles. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Waterways Expt Stn, Vicksburg, MS 39180 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. RP Forrestal, MJ (reprint author), Sandia Natl Labs, Albuquerque, NM 87185 USA. NR 4 TC 115 Z9 159 U1 3 U2 19 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD JUL PY 1998 VL 21 IS 6 BP 489 EP 497 DI 10.1016/S0734-743X(98)00008-6 PG 9 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 102NC UT WOS:000074929600006 ER PT J AU Kodama, T Donangelo, R Guidry, MW AF Kodama, T Donangelo, R Guidry, MW TI Inclusion of retardation effects in hydrodynamical calculations SO INTERNATIONAL JOURNAL OF MODERN PHYSICS C LA English DT Article DE retardation effects; hydrodynamics; supernova explosion ID CORE COLLAPSE SUPERNOVAE; II SUPERNOVAE; CONVECTION; EXPLOSIONS; MECHANISM AB In numerical large-scale hydrodynamics calculations, such as the description of a supernova explosion, instantaneous thermalization of the fluid matter is assumed independently of the size of the volume element used in the calculation. One expects, however, the appearance of transient processes such as convection currents, vortices, and other collective motion on smaller and smaller scales, which can delay equilibration. To account for these effects in a simple one-dimensional hydrodynamical calculation, we introduce retardation in the hydrodynamic equations and show that, when strong shocks are present, such effects may have considerable influence on the evolution of the system. C1 Univ Fed Rio de Janeiro, Inst Fis, BR-21945970 Rio De Janeiro, Brazil. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Kodama, T (reprint author), Univ Fed Rio de Janeiro, Inst Fis, CP 68528, BR-21945970 Rio De Janeiro, Brazil. RI Kodama, Takeshi/H-2381-2011 OI Kodama, Takeshi/0000-0001-7718-9874 NR 19 TC 8 Z9 8 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 JUL PY 1998 VL 9 IS 5 BP 745 EP 758 DI 10.1142/S0129183198000650 PG 14 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 118AX UT WOS:000075816000009 ER PT J AU Zhang, Y Woloschak, GE AF Zhang, Y Woloschak, GE TI Detection of codon 12 point mutations of the K-ras gene from mouse lung adenocarcinoma by 'enriched' PCR SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID AQUATICUS DNA-POLYMERASE; PROCESSED PSEUDOGENE; THYMIC LYMPHOMA; TUMOR-ANTIGEN; ACTIVATION; RADIATION; ONCOGENES; CELLS; TRANSFORMATION; CARCINOGENESIS AB Purpose: Recent studies have shown that chemical carcinogens induce a high frequency of point mutations in the K-ras oncogene from mouse lung tumours at codons 12, 13 and 61. These experiments were performed to identify K-ras mutations in tissues from control and radiation-exposed mice. Materials and methods: By modifying the technique of the 'enriched' polymerase chain reaction (PCR), it was possible to detect point mutations at codon 12 of the K-ras oncogene from 25-year-old paraffin-embedded normal lungs and lung adenocarcinomas from mice exposed to radiation. Together, a total of 120 lung tissues were screened for point mutations at codon 12 of the K-ras oncogene in this study. Results: A significant increase in K-ras codon 12 point mutations was observed in the normal lungs from mice exposed to 24 once-weekly neutron irradiations (100%), compared with normal lungs from mice with sham-irradiation (50%) (p<0.05). Lung adenocarcinomas from mice receiving 24 once-weekly neutron irradiations also had a significantly higher frequency of K-ras codon 12 point mutations (100%) than the lung adenocarcinomas of mice receiving 24 or 60 once-weekly gamma-ray irradiations (50%), but the higher frequency was not significantly different from that in spontaneous lung adenocarcinomas from mice (75%; p>0 05). The validity of the technique was confirmed by sequencing two of the mutants. In doing so, a K-ras 13(Asp) point mutation was observed. Conclusions: The data suggest that high-linear energy transfer (LET) neutron radiation was more effective than low-LET gamma-rays in inducing K-ras point mutations at codon 12 in the lungs of BGCF(1) mice. C1 Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, Argonne, IL 60439 USA. RP Woloschak, GE (reprint author), Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, 9700 S Cass Ave, Argonne, IL 60439 USA. EM woloschak@anl.gov RI Woloschak, Gayle/A-3799-2017 OI Woloschak, Gayle/0000-0001-9209-8954 FU NIEHS NIH HHS [ES 07141-02] NR 41 TC 5 Z9 5 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD JUL PY 1998 VL 74 IS 1 BP 43 EP 51 PG 9 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA ZZ889 UT WOS:000074778800005 PM 9687974 ER PT J AU Strobel, GL AF Strobel, GL TI Rest frame properties of the proton SO INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS LA English DT Article ID 2-BODY DIRAC-EQUATION; QUARK-MODEL; POTENTIALS AB The proton is modeled as three quarks of small current quark mass. The three-body Dirac equation is solved with spin-independent central diagonal linear confining potentials with an attractive Coulombic term in a relativistic three-quark model. Hyperspherical coordinates are used, and the bound state is found analytically. After integrating over the hyperangles, the Hamiltonian is an 8 by 8 matrix of coupled first-order differential equations in one variable, the hyperradius. These are analytically solved in hypercentral approximation. For the (1/2(+))(3) ground-state configuration in the nonrelativistic large-quark-mass limit, there are no nodes in the wave function. However, in the extreme relativistic limit of small current quark masses of a few MeV, the expectation value of the number of nodes is about 1.30 when the potential parameters are chosen to reproduce the proton rms charge radius. The quarks are assumed to possess a Pauli anomalous magnetic moment, like that of the electron and muon of (alpha/2 pi)(e/m). Assuming all three quarks have equal mass, one can fit the rest energy, magnetic moment, rms charge radius, and axial charge of the proton with this relativistic three-body Dirac equation model. The solution found shows the necessity of including all components of the composite three-quark wave function, as the upper component contributes only 0.585 to the norm. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Georgia, Dept Phys, Athens, GA 30602 USA. RP Strobel, GL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 22 TC 6 Z9 6 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0020-7748 J9 INT J THEOR PHYS JI Int. J. Theor. Phys. PD JUL PY 1998 VL 37 IS 7 BP 2001 EP 2019 DI 10.1023/A:1026621415068 PG 19 WC Physics, Multidisciplinary SC Physics GA 121UK UT WOS:000076032300007 ER PT J AU Reddy, TV Olson, GR Wiechman, B Reddy, G Torsella, J Daniel, FB AF Reddy, TV Olson, GR Wiechman, B Reddy, G Torsella, J Daniel, FB TI Subchronic toxicity of 1,3,5-trinitrobenzene in Fischer 344 rats SO INTERNATIONAL JOURNAL OF TOXICOLOGY LA English DT Article; Proceedings Paper CT 33rd Annual Meeting of the Society-of-Toxicology CY MAR 13-17, 1994 CL DALLAS, TEXAS SP Soc Toxicol DE Fischer 344 rats; nitroaromatic compounds; subchronic toxicity; 1,3,5-trinitrobenzene ID LONG-TERM SEQUELAE; REPRODUCTIVE TOXICITY; 1,3-DINITROBENZENE; TRINITROTOLUENE AB The subchronic toxicity of 1,3,5-trinitrobenzene (TNB) in, male and female Fischer 344 rats was evaluated by feeding a powdered certified laboratory diet containing 0, 66.7, 400 and 800 mg TNB/kg diet for 90 days. The calculated average TNB intake was 4.29, 24.70 and 49.28 mg/kg body weight (BW)/day for females and 3.91, 22.73, and 44.16 mg/kg BW/day for males. Food intake in the 400 and 800 mg/kg diet dose groups of both sexes was decreased throughout the study and resulted in, a significant decrease in absolute body weights. A significant decrease in relative testicular weights and a significant increase in the relative liver weight were observed in, male rats receiving 400 or 800 mg TNB/kg diet. A significant increase in the relative spleen weights of both sexes receiving 400 or 800 mg TNB diet was noted. The relative liver weight was also increased only in female rats maintained on the 800 mg TNB diet. Histopathological examinations revealed that the susceptible organs for TNB toxicity were kidney (hyaline droplets) in all male dose groups and testes (seminiferous tubular degeneration) in rats receiving 400 and 800 mg TNB diet groups. The spleen was also affected (extramedullary hematopoiesis) in both sexes in the 400 and 800 mg close groups. Hematological studies at both 45 (data not given) and 90 days in the 400 and 800 mg dose groups indicated decreased values for red blood cell counts and hemoglobin content, while reticulocytes and methemoglobin levels were increased. Clinical chemistry parameters were unaffected. Based on Kidney toxicity and hematological effects, a Low Observed Adverse Effect Level (LOAEL) of 3.91 mg/kg BW/day was suggested for subchronic toxicity studies on TNB. C1 USA, Ctr Hlth Promot & Prevent Med, Aberdeen Proving Ground, MD 21010 USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN USA. US EPA, Natl Exposure Res Lab, Cincinnati, OH 45268 USA. Pathol Associates Inc, W Chester, OH USA. RP Reddy, G (reprint author), USA, Ctr Hlth Promot & Prevent Med, Bldg E-2100, Aberdeen Proving Ground, MD 21010 USA. NR 33 TC 6 Z9 6 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 1091-5818 J9 INT J TOXICOL JI Int. J. Toxicol. PD JUL-AUG PY 1998 VL 17 IS 4 BP 393 EP 411 PG 19 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA ZW829 UT WOS:000074452500002 ER PT J AU Bischof, CH Mauer, A Jones, WT Samareh, J AF Bischof, CH Mauer, A Jones, WT Samareh, J TI Experiences with automatic differentiation applied to a volume grid generation code SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 34th Aerospace Sciences Meeting and Exhibit CY JAN 15-19, 1996 CL RENO, NV SP Amer Inst Aeronaut & Astronaut AB Automatic differentiation (AD) is a methodology for developing reliable sensitivity-enhanced versions of arbitrary computer programs with little human effort. As such, it can vastly accelerate the use of advanced simulation codes in a multidisciplinary design optimization context because the time for generating and verifying derivative codes is greatly reduced. The application of the recently developed automatic differentiation of C programs (ADIC) prototype tool for ANSI-C programs on the coordinate and sensitivity calculator for multidisciplinary design optimization multiblock three-dimensional volume grid generator are reported. The ADIC-generated code can easily be interfaced with Fortran derivative codes generated with the ADIFOR AD tool for Fortran 77 programs; thus providing efficient sensitivity-enhancement techniques for multilanguage, multidiscipline problems. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Comp Sci Corp, Hampton, VA 23666 USA. RP Bischof, CH (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM bischof@mcs.anl.gov; mauer@math.uiuc.edu; w.t.jones@larc.nasa.gov; j.a.samareh@larc.nasa.gov RI Bischof, Christian/D-2897-2009 NR 14 TC 3 Z9 3 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD JUL-AUG PY 1998 VL 35 IS 4 BP 569 EP 573 DI 10.2514/2.2361 PG 5 WC Engineering, Aerospace SC Engineering GA 107FJ UT WOS:000075196300008 ER PT J AU Marathe, MV Ravi, R Sundaram, R Ravi, SS Rosenkrantz, DJ Hunt, HB AF Marathe, MV Ravi, R Sundaram, R Ravi, SS Rosenkrantz, DJ Hunt, HB TI Bicriteria network design problems SO JOURNAL OF ALGORITHMS LA English DT Article ID DECOMPOSABLE GRAPHS; SPANNING-TREES; APPROXIMATION; TIME; COMPUTATION; ALGORITHMS; BROADCAST AB We study a general class of bicriteria network design problems. A generic problem in this class is as follows: Given an undirected graph and two minimization objectives (under different cost functions), with a budget specified on the first objective, find a subgraph from a given subgraph-class that minimizes the second objective subject to the budget on the first objective. We consider three different criteria - the total edge cost, the diameter, and the maximum degree of the network. Here, we present the first polynomial-time approximation algorithms for a large class of bicriteria network design problems for the previously mentioned criteria. The following general types of results are presented. First, we develop a framework for bicriteria problems and their approximations. Second, when the two criteria are the same we present a "black box" parametric search technique. This black box takes in as input an (approximation) algorithm for the unicriterion situation and generates an approximation algorithm for the bicriteria case with only a constant factor loss in the performance guarantee. Third, when the two criteria are the diameter and the total edge costs we use a cluster-based approach to devise a approximation algorithms - the solutions output violate both the criteria by a logarithmic factor. Finally, for the class of treewidth-bounded graphs, we provide pseudo-polynomial-time algorithms for a number of bicriteria problems using dynamic programming. We show how these pseudo-polynomial-time algorithms can be converted to fully polynomial-time approximation schemes using a scaling technique. (C) 1998 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Carnegie Mellon Univ, GSIA, Pittsburgh, PA 15213 USA. Delta Trading Co, Cambridge, MA USA. SUNY Albany, Dept Comp Sci, Albany, NY 12222 USA. Princeton Univ, DIMACS, Princeton, NJ 08544 USA. MIT, LCS, Cambridge, MA 02139 USA. RP Marathe, MV (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS B265, Los Alamos, NM 87545 USA. NR 34 TC 93 Z9 93 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0196-6774 J9 J ALGORITHM JI J. Algorithms PD JUL PY 1998 VL 28 IS 1 BP 142 EP 171 DI 10.1006/jagm.1998.0930 PG 30 WC Computer Science, Theory & Methods; Mathematics, Applied; Logic SC Computer Science; Mathematics; Science & Technology - Other Topics GA ZU153 UT WOS:000074167600007 ER PT J AU Van Berkel, GJ AF Van Berkel, GJ TI Electrolytic corrosion of a stainless-steel electrospray emitter monitored using an electrospray-photodiode array system SO JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY LA English DT Article DE electrospray; stainless steel; emitter corrosion; photodiode array; tris(1,10-phenanthroline)iron(II); electrospray mass spectrometry ID MASS-SPECTROMETRY; CELL; CHEMISTRY AB An electrospray-photodiode array (ES-PDA) system provides a useful alternative to ES-RIS for the study of the electrolytic reactions that occur at the point of high voltage (or ground) contact in an ES ion source emitter. These electrolytic reactions charge-balance the loss of an excess of ions of one polarity in the charged ES droplets. This ES-PDA approach is particularly useful when the redox products are either neutral or difficult to detect in the pas phase unaltered. The latter is the case for the multiply charged metal ions derived from ES emitter corrosion. In this study, the anodic corrosion of iron in a stainless-steel ES emitter, detected optically as tris(1,10-phenanthroline)iron(II), [Fe(phen)(3)](2+), was found using the ES-PDA system to account for the majority of the charge-balancing current under the conditions used. The metal ions derived from emitter corrosion may be produced at levels sufficient to cause chemical background problems in ES-MS. Probably because of the relatively high concentration detection Limits of ES-MS for multiply charged inorganic species, this problem has not yet been a major issue. One expects further use of ES as a nebulization source for ICP-AES and ICP-R IS, because of the much better concentration detection limits of these techniques, to bring this issue to the forefront. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Van Berkel, GJ (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 18 TC 27 Z9 27 U1 0 U2 3 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 0267-9477 J9 J ANAL ATOM SPECTROM JI J. Anal. At. Spectrom. PD JUL PY 1998 VL 13 IS 7 BP 603 EP 607 DI 10.1039/a800373d PG 5 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 103HX UT WOS:000074965100003 ER PT J AU Cleghorn, SJC Derouin, CR Wilson, MS Gottesfeld, S AF Cleghorn, SJC Derouin, CR Wilson, MS Gottesfeld, S TI A printed circuit board approach to measuring current distribution in a fuel cell SO JOURNAL OF APPLIED ELECTROCHEMISTRY LA English DT Article DE fuel cell; segmented electrode; current distribution; water distribution ID POLYMER-ELECTROLYTE; MODEL; MANAGEMENT; WATER AB A new method of measuring current distribution in a polymer electrolyte fuel cell of active area 100 cm(2) has been demonstrated, using a printed circuit board (PCB) technology to segment the current collector and flow field. The PCB technique was demonstrated to be an effective approach to fabricating a segmented electrode and provide a useful tool for analysing cell performance at different reactant gas flow rates and humidification strategies. In this initial chapter of work with the segmented cell, we describe measured effects on current distribution of cathode and anode gas stream humidification levels in a hydrogen/air cell, utilizing a Nafion(TM) 117 membrane and single serpentine channel flow fields, and operating at relatively high gas flow rates. Effects of the stoichiometric Bow of air are also shown. A clear trend is seen, apparently typical for a thick ionomeric membrane, of lowering in membrane resistance down the flow channel, bringing about the highest local current density near the air outlet. This trend is reversed at low stoichiometric hows of air. At an air flow rate less than three times stoichiometry, the local performance starts to drop significantly from inlet to outlet, as local oxygen concentration drop overshadows the lowering in resistance along the direction of flow. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Cleghorn, SJC (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS D429, Los Alamos, NM 87545 USA. NR 15 TC 181 Z9 187 U1 2 U2 22 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0021-891X J9 J APPL ELECTROCHEM JI J. Appl. Electrochem. PD JUL PY 1998 VL 28 IS 7 BP 663 EP 672 DI 10.1023/A:1003206513954 PG 10 WC Electrochemistry SC Electrochemistry GA 122AJ UT WOS:000076048000001 ER PT J AU Ramasubramanian, M Popov, BN White, RE Chen, KS AF Ramasubramanian, M Popov, BN White, RE Chen, KS TI Solution equilibrium characteristics of electroless copper deposition on thermally-activated palladium-catalysed polyimide substrates SO JOURNAL OF APPLIED ELECTROCHEMISTRY LA English DT Article DE electroless copper; solution equilibrium model; deposition rate AB Solution equilibrium characteristics of two electroless copper baths containing EDTA and tartrate as the complexing agents were studied as functions of pH. Equilibrium diagrams were constructed for both Cu-tartrate and Cu-EDTA systems. It was determined that copper is chiefly complexed as Cu2L2 in acidic conditions and as Cu(OH)(2)L-2(-4) in alkaline conditions in the tartrate bath, and as CuA(-2) in the EDTA bath, where L and A are the complexing tartrate and EDTA ligands, respectively. Electroless copper deposition rates were studied from a tartrate bath on thermally activated palladium-catalysed polyimide substrates as functions of copper and formaldehyde concentrations, and pH. C1 Univ S Carolina, Dept Chem Engn, Columbia, SC 29208 USA. Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. RP Ramasubramanian, M (reprint author), Univ S Carolina, Dept Chem Engn, Columbia, SC 29208 USA. NR 15 TC 10 Z9 10 U1 1 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0021-891X J9 J APPL ELECTROCHEM JI J. Appl. Electrochem. PD JUL PY 1998 VL 28 IS 7 BP 737 EP 743 DI 10.1023/A:1003202413045 PG 7 WC Electrochemistry SC Electrochemistry GA 122AJ UT WOS:000076048000010 ER PT J AU Malyshev, MV Donnelly, VM Kornblit, A Ciampa, NA AF Malyshev, MV Donnelly, VM Kornblit, A Ciampa, NA TI Percent dissociation of Cl-2 in inductively coupled, chlorine-containing plasmas SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID DENSITY; SIMULATION; REACTOR; SI AB percent dissociation of Cl-2 was determined for two configurations of a,commercial transformer-coupled plasma (TCP) reactor (LAM Research Alliance metal etcher), using Cl-2 and BCl3/Cl-2 feed gases, during slow etching of SiO2 covered Si wafers. Emission from Cl-2 at 305 nm was recorded as a function of TCP source power, along with emission from 1% Ar and Xe, added as part of an equal mixture of the five rare gases. Absolute Cl-2 number densities were determined from the Cl-2-to-rare gas emission intensity ratios. The CI, percent dissociation increases with power, reaching 70% between 1 and 2 mTorr at the highest power (900 W, 0.080 W/cm(3)). The percent dissociation decreases with increasing pressure between 1 and 10 mTorr. Decreasing the gap between the TCP window and the wafer chuck from 11 to 6.5 cm decreases dissociation at pressures between 0.5 and 2 mTorr, and-increases dissociation slightly at 10 mTorr. The percent dissociation as a function of power, and for the most part as a function of pressure and gap, is reproduced by a zero-dimensional model that includes electron-impact dissociation and dissociative attachment of Cl-2, and diffusion-controlled recombination of Cl at the walls. Addition of BCl3 to Cl-2 increases the percent dissociation of Cl-2, most likely due to a passivation of the chamber walls by adsorbed BCl,, lowering the CI-atom recombination coefficient. (C) 1998 American Institute of Physics. C1 AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08544 USA. RP Malyshev, MV (reprint author), AT&T Bell Labs, Lucent Technol, 600 Mt Ave, Murray Hill, NJ 07974 USA. EM vmd@bell-labs.com NR 24 TC 87 Z9 87 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUL 1 PY 1998 VL 84 IS 1 BP 137 EP 146 DI 10.1063/1.368010 PG 10 WC Physics, Applied SC Physics GA 108GP UT WOS:000075258100016 ER PT J AU Edgar, JH Gao, Y Chaudhuri, J Cheema, S Casalnuovo, SA Yip, PW Sidorov, MV AF Edgar, JH Gao, Y Chaudhuri, J Cheema, S Casalnuovo, SA Yip, PW Sidorov, MV TI Selective epitaxial growth of silicon carbide on SiO2 masked Si(100): The effects of temperature SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB The effect of substrate temperature on the growth rate, crystal grain size, and SiO2 mask stability in; the selective epitaxial growth of silicon carbide deposited, from SiH4, C2H4, and HCl1 on silicon dioxide masked silicon (100) was examined. Depositing at atmospheric pressure and a Cl/Si input ratio of 50 to achieve good selectivity, increasing the substrate temperature from 950 to 1000 degrees C increased the growth rate and the crystal size, and improved the film's surface morphology, but also enhanced the SiO2 mask degradation rate, causing a loss of selectivity for long deposition times. For prolonged deposition times at 1000 degrees C, SiC nucleation occurred at both voids formed in the mask from its reaction with the silicon substrate and on the SiO2 mask itself-a consequence of increasing oxide surface roughness. C1 Kansas State Univ, Dept Chem Engn, Manhattan, KS 66506 USA. Wichita State Univ, Dept Engn Mech, Wichita, KS 67260 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. USAF Lab, Bedford, MA 01731 USA. Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. RP Edgar, JH (reprint author), Kansas State Univ, Dept Chem Engn, Durland Hall, Manhattan, KS 66506 USA. RI Chaudhuri, Jharna/E-8863-2013 NR 12 TC 19 Z9 20 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 JUL 1 PY 1998 VL 84 IS 1 BP 201 EP 204 DI 10.1063/1.368017 PG 4 WC Physics, Applied SC Physics GA 108GP UT WOS:000075258100025 ER PT J AU You, CY Shin, SC AF You, CY Shin, SC TI Generalized analytic formulae for magneto-optical Kerr effects SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID FILMS; MULTILAYERS; TRANSITION; ANISOTROPY; CO AB We have developed simplified analytic expressions for magneto-optical Kerr effects of both optically thick and ultrathin films in the general case, where a magnetic medium had an arbitrary direction of magnetization and a beam of light was obliquely incident to the medium. It was found that the simplified analytic formulae for the Kerr effects of p and s waves consisted of a product of two factors for both optically thick and ultrathin films: the prefactor dependent only on the optical parameters of the system and the main factor of the polar Kerr effect for a normal incidence case. We have also derived some useful relations among the Kerr effects in the polar and longitudinal configurations. We-have demonstrated that the theoretical calculations using the present analytic formulae could well match the experimental polar and longitudinal Kerr rotation angles of magnetic films measured with varying incident angles. (C) 1998 American Institute of Physics. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Korea Adv Inst Sci & Technol, Dept Phys, Taejon 305701, South Korea. RP You, CY (reprint author), Argonne Natl Lab, Div Sci Mat, 9700 S Cass Ave, Argonne, IL 60439 USA. EM shin@cais.kaist.ac.kr RI You, Chun-Yeol/B-1734-2010; Shin, Sung-Chul/C-1992-2011 OI You, Chun-Yeol/0000-0001-9549-8611; NR 21 TC 42 Z9 43 U1 4 U2 13 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 JUL 1 PY 1998 VL 84 IS 1 BP 541 EP 546 DI 10.1063/1.368058 PG 6 WC Physics, Applied SC Physics GA 108GP UT WOS:000075258100077 ER PT J AU Saka, O Kitamura, T Tachihara, H Shinohara, M Trivedi, NB Reeves, GD Hansen, TL AF Saka, O Kitamura, T Tachihara, H Shinohara, M Trivedi, NB Reeves, GD Hansen, TL TI Amplitude modulation of the equatorial electrojet (EEJ) during a magnetospheric storm SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article ID DISTURBANCE DYNAMO AB An encounter of the Earth with a high velocity solar wind-stream triggered the magnetic storm of 29 January 1995. The storm lasted for the following seven days, keeping the level of the Dst index in the range of -25-50 nT. At the dip-equator, a regular enhancement of the magnetic H component during daytime, referred to as the Equatorial Electrojet (EEJ), was seen to be suppressed and modified during this storm interval. We attempted to classify the type of the EEJ modification by analyzing magnetometer data from two stations at the dip-equator but located in the opposite hemisphere, and energetic particle data from two geosynchronous satellites located close to the ground magnetometer meridian. As a result, three different types of modulation of EEJ amplitudes, with time scales of 15 min to 1 day, were found to appear during the periods when the flux level of low energy charged particles (>30 keV) in-the midnight magnetosphere was increased above the quiet level. These modulations were characterized by referring to the nightside particle signatures. We argue that, although the EEJ is a local enhancement of the ionospheric currents at the dayside dip-equator, the EEJ is definitely affected by changes of the magnetosphere, probably in various ways arising from the complexities of the storm effects. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Kurume Natl Coll Technol, Dept Phys, Kurume, Fukuoka 830, Japan. Kyushu Univ, Dept Earth & Planetary Sci, Fukuoka, Japan. Inst Nacl Pesquisas Espaciais, BR-12201 Sao Jose Dos Campos, SP, Brazil. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Univ Tromso, Inst Math & Phys Sci, Tromso, Norway. RP Saka, O (reprint author), Kurume Natl Coll Technol, Dept Phys, Kurume, Fukuoka 830, Japan. RI Reeves, Geoffrey/E-8101-2011 OI Reeves, Geoffrey/0000-0002-7985-8098 NR 13 TC 2 Z9 2 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD JUL PY 1998 VL 60 IS 11 BP 1129 EP 1137 DI 10.1016/S1364-6826(98)00068-6 PG 9 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 142HN UT WOS:000077194800007 ER PT J AU Loehle, C AF Loehle, C TI Height growth rate tradeoffs determine northern and southern range limits for trees SO JOURNAL OF BIOGEOGRAPHY LA English DT Article DE biogeography; trees; range limits; ecotone; climate change; North America ID LIFE-HISTORY STRATEGIES; CLIMATE-CHANGE; FOREST SUCCESSION; SIMULATION-MODEL; TEMPERATURES; POPULATIONS; PROVENANCES; RESPONSES; REGIONS; PLANTS AB Identifying the biological determinants of range limits of trees is an unsolved problem of critical importance for predicting the effects of climate change on forests. Data showing that many boreal trees can grow in temperate climates indicate that southern range limits do not necessarily result from excessive temperature per se. A growth tradeoff could exist between freezing tolerance and height growth rate if adaptations to tolerate cold climates interfered with growth. Analysis of height growth rate versus freezing tolerance for twenty-two North American trees provided evidence for such a tradeoff. Provenance trials of numerous tree species also showed that a tradeoff exists within species, indicating a genetic basis for these traits. The result of this tradeoff is that at their southern range margins most species do not suffer from too much heat but rather face competitors with a faster growth rate. The implication for future climate change is that forests will not suffer catastrophic dieback due to increased temperatures but will rather be replaced gradually by faster growing types, perhaps over hundreds of years. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Loehle, C (reprint author), Natl Council Air & Stream Improvement, 552 G Washington St,Suite 224, Naperville, IL 60540 USA. NR 48 TC 153 Z9 157 U1 2 U2 55 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0305-0270 J9 J BIOGEOGR JI J. Biogeogr. PD JUL PY 1998 VL 25 IS 4 BP 735 EP 742 DI 10.1046/j.1365-2699.1998.2540735.x PG 8 WC Ecology; Geography, Physical SC Environmental Sciences & Ecology; Physical Geography GA 146ZA UT WOS:000077462700011 ER PT J AU Keij, JF Jiang, YJ Sotiropoulos, DA Ben-Hur, E Visser, JWM AF Keij, Jan F. Jiang, Yajuan Sotiropoulos, Damianos A. Ben-Hur, Ehud Visser, Jan W. M. TI EVALUATION OF THE SILICON PHTHALOCYANINE PC 4 FOR PHOTODYNAMIC BONE MARROW PURGING SO JOURNAL OF BIOMEDICAL OPTICS LA English DT Article DE cobble stone area; murine; early progenitor cells; photosensitization AB The silicon phthalocyanine Pc 4 was tested as a photosensitizer for the selective photoinactivation of malignant cells in bone marrow transplantation samples. Using a murine model system, incubation of 1.5x10(7) cells/mL with 15 nM Pc 4 followed by exposure to red light (lambda>600 nm, fluence of 18 J/cm(2)) was shown to result in a greater than 6 log(10) reduction of the clonogenic growth for the murine cell lines ABE-8.1/2, BC3A and L1210. The clonogenic growth of WEHI-3 and P815 cells was reduced by more than 5 log(10) and more than 3 log(10), respectively. Late murine hematopoietic progenitor cells were less sensitive than cancer cells; the surviving fractions were 0.084 for the colony forming unit, megakaryocyte (CFU-Mk); 0.038 for the colony forming unit, granulocyte macrophage (CFU-GM); 0.0018 for the colony forming unit, mix (CFU-mix) and <0.003 for burst forming units, erythroid (BFU-E). Early hematopoietic progenitor cells, assayed by the in vitro cobble stone area forming cell assay, were not affected by the photodynamic treatment. Likewise, in vivo assays of early hematopoietic progenitor cells showed no reduction of their ability to repopulate the bone marrow. Irradiation of the samples following incubation of 1.5x10(6) cells/mL with Pc 4 resulted in increased photosensitivity of all cell types, including the early and late hematopoietic progenitor cells. Flow cytometric analysis of Pc 4 uptake by the cells revealed that the increased photosensitivity could be traced to increased Pc 4 uptake; however, Pc 4 uptake among cell types did not correlate with photosensitivity. When mixed with bone marrow (BM) cells, Pc 4 uptake in the cell lines increased as the fraction of BM increased from 0.5 to 0.95. These observations suggest that Pc 4 may be a suitable photosensitizer for bone marrow purging. (C) 1998 Society of Photo-Optical Instrumentation Engineers. C1 [Keij, Jan F.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Jiang, Yajuan; Sotiropoulos, Damianos A.; Visser, Jan W. M.] New York Blood Ctr, New York, NY 10021 USA. [Ben-Hur, Ehud] VITEX, Audubon Ctr, New York, NY 10032 USA. RP Ben-Hur, E (reprint author), New York Blood Ctr, New York, NY 10021 USA. EM ehud-ben-hur@juno.com FU National Heart, Lung and Blood Institute [2RO1-HL41221]; Starr Foundation FX This work was supported in part by Award No. 2RO1-HL41221 from the National Heart, Lung and Blood Institute and in part by The Starr Foundation. Thanks are due to Dr. M. E. Kenney for a gift of Pc 4. NR 39 TC 0 Z9 0 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 JUL PY 1998 VL 3 IS 3 BP 286 EP 295 DI 10.1117/1.429855 PG 10 WC Biochemical Research Methods; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Biochemistry & Molecular Biology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA V32RL UT WOS:000208968200009 PM 23015082 ER PT J AU Krishnan, VV Cosman, M AF Krishnan, VV Cosman, M TI An empirical relationship between rotational correlation time and solvent accessible surface area SO JOURNAL OF BIOMOLECULAR NMR LA English DT Article DE rotational correlation time; solvent accessible surface area; structure and dynamics ID NMR RELAXATION MEASUREMENTS; EGG-WHITE LYSOZYME; DNA-BINDING DOMAIN; BACKBONE DYNAMICS; SPIN RELAXATION; HYDRODYNAMIC PROPERTIES; TRANSLATIONAL FRICTION; INTRINSIC-VISCOSITY; MAIN-CHAIN; PROTEIN AB Structure-dynamics interrelationships are important in understanding protein function. We have explored the empirical relationship between rotational correlation times (tau(c)) and the solvent accessible surface areas (SASA) of 75 proteins with known structures. The theoretical correlation between SASA and tau(c) through the equation SASA = K(r)tau(c)((2/3)) is also considered. SASA was determined from the structure, tau(c)(calc) was determined from diffusion tensor calculations, and tau(c)(expt) was determined from NMR backbone C-13 or N-15 relaxation rate measurements. The theoretical and experimental values of tau(c) correlate with SASA with regression analyses values of K-r as 1696 and 1896 m(2)s(-(2/3)), respectively, and with corresponding correlation coefficients of 0.92 and 0.70. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Krishnan, VV (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RI Krishnan, Krish/A-6859-2010 NR 48 TC 39 Z9 39 U1 1 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0925-2738 J9 J BIOMOL NMR JI J. Biomol. NMR PD JUL PY 1998 VL 12 IS 1 BP 177 EP 182 DI 10.1023/A:1008226330666 PG 6 WC Biochemistry & Molecular Biology; Spectroscopy SC Biochemistry & Molecular Biology; Spectroscopy GA 111ZZ UT WOS:000075470000013 PM 20700691 ER PT J AU McGee, BCW Vermeulen, FE Chute, FS Vinsome, PKW Buettner, HM AF McGee, BCW Vermeulen, FE Chute, FS Vinsome, PKW Buettner, HM TI In situ decontamination of soil SO JOURNAL OF CANADIAN PETROLEUM TECHNOLOGY LA English DT Article AB Methods for decontamination of soil in situ are receiving increased attention, as the requirement to clean these sites has become a national concern. The continual and costly liability is an important corporate incentive to clean contaminated soils. The development of an effective technology for in situ decontamination is a priority issue. Some in situ decontamination processes are similar to enhanced oil recovery schemes and use an integrated heating approach. One such method consists of heating by conduction and convection in conjunction with electrical heating. Advantages of electrical heating are that the energy can be focussed and the soil heated uniformly. The integrated heating approach has been extensively tested in the United States in a joint venture between Lawrence Livermore National Laboratories (LLNL) and the University of California at Berkeley. The most significant test was done at an abandoned Naval Air Base, now named the LLNL Gasoline Spill Site. It has been demonstrated that such an integrated approach can remove hydrocarbon contaminates from in situ at an accelerated rate. The objective of this paper is to present a mathematical model that solves the heat transfer problem for the integrated heating process. The model is also used to investigate the practicality of the process in terms of energy requirements and the time it takes to clean the soil. The mathematical model combines all of the principal heat transfer mechanisms of the process. These an electrical heating, convection, conduction and accumulation of energy. In addition, conductive heat losses from the sides and bottom of the heated volume and the substantial variation of electrical resistivity with temperature are included. Calculations made using the mathematical model developed in this paper are in good agreement with results obtained with the general-purpose reservoir simulator, TETRAD. C1 Univ Alberta, Edmonton, AB T6G 2M7, Canada. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. NR 13 TC 2 Z9 2 U1 0 U2 0 PU CANADIAN INST MINING METALLURGY PETROLEUM PI CALGARY PA 101 6TH AVE SW, STE 320, CALGARY, ALBERTA TZP 3P4, CANADA SN 0021-9487 J9 J CAN PETROL TECHNOL JI J. Can. Pet. Technol. PD JUL PY 1998 VL 37 IS 7 BP 15 EP 22 PG 8 WC Energy & Fuels; Engineering, Chemical; Engineering, Petroleum SC Energy & Fuels; Engineering GA 102MZ UT WOS:000074929300006 ER PT J AU Freyer, JP AF Freyer, JP TI Decreased mitochondrial function in quiescent cells isolated from multicellular tumor spheroids SO JOURNAL OF CELLULAR PHYSIOLOGY LA English DT Article ID FLOW CYTOMETRIC ANALYSIS; NONYL-ACRIDINE-ORANGE; NUCLEAR-MAGNETIC-RESONANCE; OXYGEN-CONSUMPTION; GROWTH SATURATION; DIFFERENT REGIONS; LEUKEMIC-CELLS; RHODAMINE 123; GLUCOSE; CYCLE AB Cells in the inner region of multicellular spheroids markedly reduce their oxygen consumption rate, presumably in response to their stressful microenvironment. To determine the mechanism behind this metabolic adaptation, we have investigated relative mitochondrial mass and mitochondrial function in cells isolated from different regions of tumor spheroids by using a combination of mitochondrial-specific fluorescent stains and flow cytometric analysis. Uptake of rhodamine 123 (R123) is driven by the mitochondrial membrane potential and thus reflects mitochondrial activity. Uptake of 10-nonyl-acridine orange (NAO) reflects total mitochondrial mass independently of activity because this compound binds to cardiolipin in the inner mitochondrial membrane. NAO fluorescence per unit cell volume only decreased 10-20% for cells from the inner spheroid region compared with those near the surface. There was greater than a twofold reduction in R123 fluorescence in the inner region cells, however. Thus, tumor cells in spheroids alter their rate of respiration predominately by downregulating mitochondrial function as opposed to degradation of mitochondria. There was a correlation between R123 staining per unit cell volume and the growth fraction of the cells from spheroids, but not for monolayer cultures. We also show a linear correlation between R123 staining and the rate of oxygen consumption for both monolayer-and spheroid-derived cells. After separating the inner region cells from the spheroid and replating them in monolayer culture, the R123 uptake recovered to normal levels prior to entry of the cells into S-phase. This reduction in mitochondrial function in quiescent cells from spheroids can explain the long period required for these cells to re-enter the cell cycle and may have important implications for the regulation of tu mor cell oxygenation in vivo. (C) 1998 Wiley-Liss, Inc. C1 Univ Calif Los Alamos Natl Lab, Div Life Sci, Cell & Mol Biol Grp, Los Alamos, NM 87545 USA. RP Freyer, JP (reprint author), Univ Calif Los Alamos Natl Lab, Div Life Sci, Cell & Mol Biol Grp, Mail Stop M888, Los Alamos, NM 87545 USA. FU NCI NIH HHS [CA-51150]; NCRR NIH HHS [RR01315] NR 55 TC 55 Z9 57 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 0021-9541 J9 J CELL PHYSIOL JI J. Cell. Physiol. PD JUL PY 1998 VL 176 IS 1 BP 138 EP 149 DI 10.1002/(SICI)1097-4652(199807)176:1<138::AID-JCP16>3.0.CO;2-3 PG 12 WC Cell Biology; Physiology SC Cell Biology; Physiology GA ZP476 UT WOS:000073757300016 PM 9618154 ER PT J AU Mio, C Kiritsov, S Thio, Y Brafman, R Prausnitz, J Hawker, C Malmstrom, EE AF Mio, C Kiritsov, S Thio, Y Brafman, R Prausnitz, J Hawker, C Malmstrom, EE TI Vapor-liquid equilibria for solutions of dendritic polymers SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID SOLVENT-INDUCED CRYSTALLIZATION; ISOTACTIC POLYPROPYLENE; DENDRIMERS; PROBE AB Vapor-liquid equilibrium data were obtained for dendritic polymer solutions using a classic isothermal gravimetric-sorption method; the amount of solvent absorbed by the dendrimer was measured at increasing solvent activity. The polymers were polyamidoamine (PAMAM) dendrimers of generations 1, 2, and 4 and benzyl ether dendrimers with different end groups (aromatic rings, dodecyl chains, methyl ester groups, perfluoroalkyl chains) of generations 2 to 6, and two series of benzyl ether linear polymers that are analogues of the dendrimers. Solvents were acetone, acetonitrile, chloroform, cyclohexane, methanol, n-pentane, n-propylamine, tetrahydrofuran, and toluene. The temperature range was 35 to 89 degrees C. The amount of solvent absorbed by the dendrimers depends, sometimes strongly, on the kind of dendrimer end groups. The relation between solvent absorption and dendrimer generation number, or molecular weight, depends on the solvent-dendrimer system and on temperature. Solvent absorption in linear polymers is below that for corresponding dendrimers, all or in part owing to crystallinity in the linear polymers. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. IBM Corp, Almaden Res Ctr, Ctr Polymer Interfaces & Macromol Assemblies, San Jose, CA 95120 USA. RP Prausnitz, J (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. NR 35 TC 34 Z9 34 U1 2 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD JUL-AUG PY 1998 VL 43 IS 4 BP 541 EP 550 DI 10.1021/je970226q PG 10 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA ZZ680 UT WOS:000074755800010 ER PT J AU Albright, JG Gillespie, SM Rard, JA Miller, DG AF Albright, JG Gillespie, SM Rard, JA Miller, DG TI Ternary solution mutual diffusion coefficients and densities of aqueous mixtures of NaCl and Na2SO4 at 298.15 K for six different solute fractions at a total molarity of 1.000 mol center dot dm(-3) SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID RAYLEIGH INTERFEROMETRY; CONCENTRATION RATIO; ISOPIESTIC DETERMINATION; OSMOTIC COEFFICIENTS; MGCL2 CONCENTRATIONS; WIDE-RANGE; 25-DEGREES-C; NACL-MGCL2-H2O; INSTABILITIES; SODIUM AB Isothermal mutual diffusion coefficients (interdiffusion coefficients) were measured for ternary aqueous mixtures of NaCl and Na2SO4 at a constant total molarity of 1.000 mol . dm(-3) and 298.15 K. Measurements were performed using Rayleigh interferometry with computerized data acquisition at NaCl molarity fractions of z(1) = 1, 0.90, 0.75, 0.50, 0.25, and 0. Densities of the solutions were measured with a vibrating tube densimeter. At all ternary solution compositions, one cross-term diffusion coefficient has negative values whereas the other has positive values. These measurements supplement our earlier results at 0.500 mol . dm(-3). Both main-term diffusion coefficients are significantly smaller at 1.000 mol . dm(-3) than at 6.500 mol . dm(-3) at any fixed value of z(1), whereas both cross-term coefficients are shifted in a positive direction. Trace diffusion coefficients D*(Cl-) and D*(SO42-) were extrapolated from these results for the Cl-(aq) ion in 1.0 mol . dm(-3) Na2SO4(aq) and for the SO42-(aq) ion in 1.0 mol . dm(-3) NaCl(aq). Values of D*(Cl-) in Na2SO4(aq) and in NaCl(aq) were found to be essentially identical, as were D*(SO42-) in these same two electrolytes, provided the comparisons were made at the same volumetric ionic strengths. C1 Texas Christian Univ, Dept Chem, Ft Worth, TX 76129 USA. Univ Calif Lawrence Livermore Natl Lab, Earth & Environm Sci Directorate, Livermore, CA 94550 USA. RP Albright, JG (reprint author), Texas Christian Univ, Dept Chem, Ft Worth, TX 76129 USA. NR 45 TC 9 Z9 9 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD JUL-AUG PY 1998 VL 43 IS 4 BP 668 EP 675 DI 10.1021/je9800196 PG 8 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA ZZ680 UT WOS:000074755800037 ER PT J AU Bond, AH Rogers, RD AF Bond, AH Rogers, RD TI Synthesis and X-ray crystallographic characterization of [Cd(NO3)(2)(15-crown-5)] and [Cd(NO3)(2)(18-crown-6)] SO JOURNAL OF CHEMICAL CRYSTALLOGRAPHY LA English DT Article DE cadmium; crown ether; 15-crown-5; 18-crown-6; crystal structure ID POLYETHYLENE-GLYCOL COMPLEXATION; MACROCYCLIC LIGANDS; MOLECULAR-STRUCTURE; CROWN-ETHER; O2N3-DONOR MACROCYCLES; CADMIUM(II) CHLORIDE; CRYSTAL-STRUCTURES; 15-CROWN-5 ETHER; LONE-PAIR; ZINC(II) AB Reaction of 15-crown-5 or 18-crown-6 in 3:1 (v/v) CH3CN:CH3OH with Cd(NO3)(2). 4H(2)O followed by slow evaporation produces [Cd(NO3)(2)(15-crown-5)] or [Cd(NO3)(2)(18-crown-6)]. Crystals of [Cd(NO3)(2)(15-crown-5)] are orthorhombic with space group Pbca and cell parameters a = 13.562(5), b = 15.941(9), and c = 15.011(7) Angstrom at 295 K. [Cd(NO3)(2)(18-crown-6)] crystallizes in the monoclinic space group C2/c with a = 11.235(2), b = 11.196(5), c = 15.385(3) Angstrom, and beta = 99.89(2)degrees at 295 K. The metal center in [Cd(NO3)(2)(15-crown-5)] rests atop the macrocyclic donor array with two cis-bound nitrate anions and adopts a distorted tricapped trigonal prismatic geometry. [Cd(NO3)(2)(18-crown-6)] resides on an equatorial twofold rotation axis with Cd2+ coordinated in the 18-crown-6 cavity and the nitrate anions oriented in twisted trans positions. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Alabama, Dept Chem, Tuscaloosa, AL 35487 USA. RP Bond, AH (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Rogers, Robin/C-8265-2013; G, Neela/H-3016-2014 OI Rogers, Robin/0000-0001-9843-7494; NR 48 TC 16 Z9 16 U1 0 U2 4 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1074-1542 J9 J CHEM CRYSTALLOGR JI J. Chem. Crystallogr. PD JUL PY 1998 VL 28 IS 7 BP 521 EP 527 DI 10.1023/A:1023239921542 PG 7 WC Crystallography; Spectroscopy SC Crystallography; Spectroscopy GA 152PM UT WOS:000077786000003 ER PT J AU Curtiss, LA Redfern, PC Raghavachari, K Pople, JA AF Curtiss, LA Redfern, PC Raghavachari, K Pople, JA TI Assessment of Gaussian-2 and density functional theories for the computation of ionization potentials and electron affinities SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID QUADRATIC CONFIGURATION-INTERACTION; SET MODEL CHEMISTRY; MOLECULAR-ENERGIES; 2ND-ROW COMPOUNDS; APPROXIMATION; EXCHANGE; ACCURATE; GAS AB A set of 146 well-established ionization potentials and electron affinities is presented. This set, referred to as the G2 ion test set, includes the 63 atoms and molecules whose ionization potentials and electron affinities were used to test Gaussian-2 (G2) theory [J. Chem. Phys. 94, 7221 (1991)] and 83 new atoms and molecules. It is hoped that this new test set combined with the recently published test set of enthalpies of neutral molecules [J. Chem. Phys. 106, 1063 (1997)] will provide a means for assessing and improving theoretical models. From an assessment of G2 and density functional theories on this test set, it is found that G2 theory is the most reliable method. It has an average absolute deviation of 0.06 eV for both ionization potentials and electron affinities. The two modified versions of G2 theory, G2(MP2, SVP) and G2(MP2) theory, have average absolute deviations of 0.08-0.09 eV for both ionization potentials and electron affinities. The hybrid B3LYP density functional method has the smallest average absolute deviation (0.18 eV) of the seven density functional methods tested for ionization potentials. The largest deviation for the density functional methods is for the ionization potential of CN (>1 eV). The BLYP density functional method has the smallest average absolute deviation (0.11 eV) of the seven density functional methods tested for electron affinities. while the BPW91, B3LYP, and B3PW91 methods also do quite well. (C) 1998 American Institute of Physics. [S0021-9606(98)02519-7]. C1 Argonne Natl Lab, Div Chem, Div Mat Sci, Argonne, IL 60439 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. RP Curtiss, LA (reprint author), Argonne Natl Lab, Div Chem, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 34 TC 442 Z9 443 U1 4 U2 35 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 JUL 1 PY 1998 VL 109 IS 1 BP 42 EP 55 DI 10.1063/1.476538 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 108FL UT WOS:000075255300006 ER PT J AU McCormack, EF Di Teodoro, F Grochocinski, JM Pratt, ST AF McCormack, EF Di Teodoro, F Grochocinski, JM Pratt, ST TI Dynamics of Rydberg states of nitric oxide probed by two-color resonant four-wave mixing spectroscopy SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID OPTICAL DOUBLE-RESONANCE; INDUCED GRATING SPECTROSCOPY; MULTIPHOTON IONIZATION TECHNIQUE; EXCITED-STATES; QUANTUM DEFECT; NO MOLECULE; 4-WAVE-MIXING SPECTROSCOPY; ROTATIONAL AUTOIONIZATION; MULTISTATE INTERACTIONS; SPECTRA AB Two-color resonant four-wave mixing (TC-RFWM) spectroscopy has been used to probe highly excited v = 0 and v = 1 Rydberg states of nitric oxide. Transitions to n = 16-30, v = 0, Rydberg states, and the 8p, 9p, 7f, 8f, 8s, and 9s, v = 1 Rydberg states from the A (2)Sigma(+), v' = 0 and 1 states have been recorded. The decay rate of the 8p and 9p, v = 1 states has been extracted from the observed line profiles by using a recently developed model for the excitation of quasibound resonances in TC-RFWM spectroscopy. Transitions from the A (2)Sigma(+), v' = 1 state to the X (2)Pi(3/2), v " = 10 state have also been observed, allowing an absolute calibration of the TC-RFWM signal intensity. This calibration is used to determine an excited-state absorption cross section for the 9p, v = 1 Rydberg state. (C) 1998 American Institute of Physics. [S0021-9606(98)01625-0]. C1 Bryn Mawr Coll, Bryn Mawr, PA 19010 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Bryn Mawr Coll, Bryn Mawr, PA 19010 USA. NR 66 TC 15 Z9 15 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 1998 VL 109 IS 1 BP 63 EP 71 DI 10.1063/1.476540 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 108FL UT WOS:000075255300008 ER PT J AU Germann, TC Miller, WH AF Germann, TC Miller, WH TI Quantum mechanical calculation of resonance tunneling in acetylene isomerization via the vinylidene intermediate SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POTENTIAL-ENERGY SURFACE; DISCRETE VARIABLE REPRESENTATION; VIBRATIONALLY EXCITED ACETYLENE; MINIMAL RESIDUAL ALGORITHM; LINEAR-SYSTEMS; PHOTOELECTRON-SPECTROSCOPY; UNIMOLECULAR REACTION; KETENE ISOMERIZATION; GROUND-STATE; SCATTERING AB Microcanonical rate constants for the acetylene isomerization reaction have been computed using the direct cumulative reaction probability methodology of Seideman and Miller [J. Chem, Phys. 96, 4412 (1992); 97, 2499 (1992)] and Manthe and Miller [J. Chem. Phys. 99, 3411 (1993)]. Two- and three-degree-of-freedom calculations an reported using a normal mode Hamiltonian based on the geometry of the vinylidene intermediate. Due to the vinylidene well, numerous resonances are found in the isomerization rate. Little coupling is found between the CH2 rock reaction coordinate and the other normal modes, so that the resonances are readily assignable as normal mode progressions. Qualitatively similar results are obtained using two different potential energy surfaces, or different reduced dimensionality sets of coordinates. (C) 1998 American Institute of Physics. [S0021-9606(98)02225-9]. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Germann, TC (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-11,MS B262, Los Alamos, NM 87545 USA. NR 33 TC 23 Z9 23 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 1998 VL 109 IS 1 BP 94 EP 101 DI 10.1063/1.476544 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 108FL UT WOS:000075255300012 ER PT J AU Fanourgakis, GS Farantos, SC Luder, C Velegrakis, M Xantheas, SS AF Fanourgakis, GS Farantos, SC Luder, C Velegrakis, M Xantheas, SS TI Photofragmentation spectra and structures of Sr+Arn, n=2-8 clusters: Experiment and theory SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; DISSOCIATION-ENERGIES; WAVE-FUNCTIONS; ATOMS; PHOTODISSOCIATION; DYNAMICS; AR; SPECTROSCOPY; POTENTIALS AB The total photofragmentation cross sections of size selected Sr+ Ar-n, n = 2-8, clusters have been recorded in a time of flight (TOF) mass spectrometer, In the energy range of 21 000-27 000 cm(-1) three absorption bands are observed that are attributed to transitions from the ground to the three excited stales that correlate to the 5p orbitals of strontium. No vibrational structure in the spectral bands is observed, even in regions where the spectrum is recorded with a resolution of 1 cm(-1). The absorption spectra are calculated within a semiclassical approximation. Accurate ab initio calculations for the ground X (2)Sigma and the A (2)Pi and B (2)Sigma excited slates of Sr+Ar are combined with a perturbative one-electron model, which includes the spin-orbit coupling, to construct potential energy surfaces for the excited states of all clusters. The theoretical spectra obtained without using any adjustable parameters reproduce the patterns and trends of the experimental spectra, but they are shifted to higher frequencies. A better agreement between theoretical and experimental spectra is obtained by adjusting the depth of the potential wells of the ground X (2)Sigma and excited A (2)Pi states of the Sr+Ar dimer to the experimentally estimated values. From both calculations we conclude that Sr+Ar3 is a trigonal pyramid of C-3v Symmetry and Sr+Ar6 has a C-5v symmetry with five argon atoms forming a regular pentagon, one argon atom below and the cation above the pentagon plane. For these clusters, theory reproduces the characteristic blue shifts found in the absorption spectra and the splittings of the doubly degenerate states encountered in these symmetric complexes. (C) 1998 American Institute of Physics. [S0021-9606(98)02125-4]. C1 Fdn Res & Technol Hellas, Inst Elect Struct & Laser, Iraklion 71110, Greece. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Crete, Dept Chem, Rethymnon, Greece. RP Fanourgakis, GS (reprint author), Fdn Res & Technol Hellas, Inst Elect Struct & Laser, Iraklion 71110, Greece. RI Velegrakis, Michalis/F-7810-2011; FARANTOS, STAVROS/H-5429-2011; Xantheas, Sotiris/L-1239-2015 OI FARANTOS, STAVROS/0000-0003-1909-7976; NR 52 TC 29 Z9 29 U1 2 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 JUL 1 PY 1998 VL 109 IS 1 BP 108 EP 120 DI 10.1063/1.476527 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 108FL UT WOS:000075255300014 ER PT J AU Palmer, BJ AF Palmer, BJ TI Direct simulation of hydrodynamic relaxation in microchannels SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS; SOLID-SURFACES; LIQUID; TEMPERATURE; SHEAR; FLOW; FLUIDS; FILMS; WATER AB Simulations were performed on a fluid confined between two parallel walls. The fluid is modeled by a Lennard-Jones potential and the walls by a simple cubic lattice of harmonically bonded sites. A Lennard-Jones potential is also used to model the interactions between the wall and the fluid. The simulation consisted of over 30 000 sites arranged to form a liquid film approximately 35 Lennard-Jones diameters in thickness. This is large enough to begin approximating the range where classical hydrodynamics is expected to be applicable. Both equilibrium simulations and simulations of velocity transients were performed on the system. Two values of the wall-fluid interaction strength were examined, which appear to correspond to a wetting and nonwetting surface. Results from equilibrium simulations show that both the density and the stress tensor relax to their bulk values within a short distance of the wall. Furthermore, examination of the relaxation of spontaneous momentum fluctuations indicates that there is little change in the value of transport coefficients near the boundary compared to the bulk fluid. Nonequilibrium simulations on the decay of a parabolic velocity profile, however, suggest that the decay of the profile is faster than would be predicted from classical hydrodynamics and that the type of boundary conditions that should be used in a hydrodynamic analysis may depend on the details of the wall-fluid interaction. (C) 1993 American Institute of Physics. [S0021-9606(98)50725-8]. C1 Pacific NW Natl Lab, Environm & Mol Sci Lab, Richland, WA 99352 USA. RP Palmer, BJ (reprint author), Pacific NW Natl Lab, Environm & Mol Sci Lab, Box 999, Richland, WA 99352 USA. NR 29 TC 5 Z9 6 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 1998 VL 109 IS 1 BP 196 EP 207 DI 10.1063/1.476549 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 108FL UT WOS:000075255300024 ER PT J AU Sever, LE AF Sever, LE TI Environmental contamination and health effects: What is the evidence? SO JOURNAL OF CLEAN TECHNOLOGY ENVIRONMENTAL TOXICOLOGY AND OCCUPATIONAL MEDICINE LA English DT Article DE congenital malformations; environmental contamination; environmental hazards; exposure classification; low birth weight; reporting bias ID LOW-BIRTH-WEIGHT; CONGENITAL-MALFORMATIONS; RESIDENTS; SITE C1 Battelle Ctr Publ Hlth Res & Evaluat, Seattle, WA USA. RP Sever, LE (reprint author), Battelle Seattle Res Ctr, 4000 NE 41st St, Seattle, WA 98105 USA. NR 25 TC 0 Z9 0 U1 1 U2 1 PU PRINCETON SCIENTIFIC PUBL INC PI PRINCETON PA PO BOX 2155, PRINCETON, NJ 08543 USA SN 1052-1062 J9 J CLEAN TECHNOL E T JI J. Clean Technol. Environ. Toxicol. Occup. Med. PD JUL-SEP PY 1998 VL 7 IS 3 BP 313 EP 329 PG 17 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA ZZ032 UT WOS:000074688500006 ER PT J AU Swayne, EN Newman, J Radke, CJ AF Swayne, EN Newman, J Radke, CJ TI Surface conductivity and disjoining pressure of common black films stabilized with sodium dodecyl sulfate SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE foam films; AC impedance spectroscopy; surface conductivity; disjoining pressure ID FOAM FILMS; IONIC SURFACTANT; POROUS-MEDIA AB We have conducted simultaneous measurements of the disjoining pressure and the film conductance for sodium dodecyl sulfate- (SDS-) stabilized foam films in aqueous electrolyte solutions and over a range of film thicknesses. The disjoining pressure ascertains the repulsive forces within the film while the conductance gauges the possible changes in mobilities and concentrations of the ions within the thin-film region, relative to their bulk values. The disjoining pressure is measured using a modified version of the porous-glass-plate technique. To permit electrical measurements in the same apparatus, a novel film holder was designed in which the film is formed in the annular region between two concentric, porous stainless steel disks. The inner and outer disks serve as electrodes, and they constrain the current to flow radially through the him. To avoid electroosmosis, the film conductance is obtained using AC impedance spectroscopy. New data are reported for the disjoining pressure, conductance, and film thickness of 0.002-M SDS foam films with and without added sodium nitrate. Film conductances exhibit a decrease with decreasing film thickness, which suggests a decrease in the mobility of the film ions relative to their bulk values, even for films as thick as 40 mn. Surface-charge densities are estimated from the conductance data and are consistent with available surface tension data. However, the surface-charge densities estimated from the disjoining-pressure data are more than an order of magnitude smaller than the values estimated from conductance and surface-tension data. Improvements in both experimental precision and theory are needed to overcome this discrepancy. (C) 1998 Academic Press. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Radke, CJ (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RI Newman, John/B-8650-2008 OI Newman, John/0000-0002-9267-4525 NR 34 TC 7 Z9 7 U1 0 U2 6 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD JUL 1 PY 1998 VL 203 IS 1 BP 69 EP 82 DI 10.1006/jcis.1998.5520 PG 14 WC Chemistry, Physical SC Chemistry GA ZV944 UT WOS:000074358000007 ER PT J AU O'Rourke, PJ Sahota, MS AF O'Rourke, PJ Sahota, MS TI A variable explicit/implicit numerical method for calculating advection on unstructured meshes SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE fluid advection; unstructured meshes; explicit/implicit numerical method ID HYPERBOLIC CONSERVATION-LAWS; FINITE-ELEMENT METHOD; INCOMPRESSIBLE-FLOW; ADAPTIVE STENCILS; SCHEME AB A variable explicit/implicit numerical method is presented for calculating fluid advection on hybrid unstructured meshes. The method is intended for unsteady flows that have a large range of advective time scales, with subregions where the how may be quasi-steady on time scales of interest. The method generalizes the method of Collins, Collela, and Glaz by providing an explicit-to-implicit switching criterion that is suitable for use on unstructured meshes. No directional splitting is used; upwinding is in the direction of the material velocity, and thus we define and use a new multidimensional limited gradient that generalizes Van Leer's MUSCL limiting [7]. After reviewing the one-dimensional method of Collins, Collela, and Glaz, we present the generalization to hybrid unstructured grids and detail the results of four example calculations that demonstrate the accuracy and flexibility of the new method. (C) 1998 Academic Press. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. EM pjor@lanl.gov NR 24 TC 24 Z9 25 U1 2 U2 2 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 JUL 1 PY 1998 VL 143 IS 2 BP 312 EP 345 DI 10.1006/jcph.1998.5903 PG 34 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA ZY201 UT WOS:000074596400002 ER PT J AU Najm, HN Wyckoff, PS Knio, OM AF Najm, HN Wyckoff, PS Knio, OM TI A semi-implicit numerical scheme for reacting flow I. Stiff chemistry SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE implicit; stiff; chemistry; reacting; flow; projection ID JET DIFFUSION FLAMES; CHEMICAL-KINETICS; ATMOSPHERIC CHEMISTRY; TURBULENT COMBUSTION; ODE SOLVER; EQUATIONS; MODELS; VORTEX; INTEGRATION; SIMULATIONS AB An additive semi-implicit projection scheme for the simulation of unsteady combustion in two dimensions is constructed. The scheme relies on a zero-Mach number formulation of the compressible conservation equations with detailed chemistry. The governing equations are discretized in space using second-order differences and integrated in time using a semi-implicit approach. Time integration of the evolution equations for species mass fraction, thermodynamic pressure, and density is performed using a semi-implicit, nonsplit scheme that combines a second-order predictor-corrector treatment of convection and diffusion terms, and a stiff integrator for the reaction source terms. Meanwhile, the momentum equations are integrated using a second-order projection scheme. The projection scheme is based on a predictor-corrector approach that couples the evolution of the Velocity and density fields in order to stabilize computations of reacting flows with large density variations. A pressure Poisson equation is inverted following both the predictor and corrector steps using a fast solver. The advantages of the stiff integration of reaction source terms are analyzed by comparing the performance of the scheme to that of a predictor-corrector scheme in which reaction and diffusion are integrated in a similar nonstiff fashion. The comparison in based on both one-dimensional (1D) unsteady tests of a premixed methane-air flame, and unsteady two-dimensional tests of the same flame interacting with a counterrotating Vortex pair. In both cases, the GRImech 1.2 reaction mechanism with 32 species and 177 elementary reactions is used. Computed results show that the stiff reaction scheme enables selection of larger time steps and thus leads to substantial improvement in the performance of the computations. For the present reaction mechanism and flame conditions, speedup factors of about 10 are achieved in the 1D tests and about five in two dimensions. Possible extensions of the present scheme to further improve efficiency are also discussed. (C) 1998 Academic Press. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Johns Hopkins Univ, Dept Mech Engn, Baltimore, MD 21218 USA. RP Najm, HN (reprint author), Sandia Natl Labs, POB 969,MS 9051, Livermore, CA 94551 USA. RI Knio, Omar/A-3318-2010 NR 62 TC 134 Z9 136 U1 1 U2 11 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JUL 1 PY 1998 VL 143 IS 2 BP 381 EP 402 DI 10.1006/jcph.1997.5856 PG 22 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA ZY201 UT WOS:000074596400004 ER PT J AU Brooks, SC Herman, JS Hornberger, GM Mills, AL AF Brooks, SC Herman, JS Hornberger, GM Mills, AL TI Biodegradation of cobalt-citrate complexes: Implications for cobalt mobility in groundwater SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article DE in situ bioremediation; biogeochemistry; contaminant transport; metal-ligand complexes; sandy aquifer material; groundwater ID METAL-IONS; MANGANESE-DIOXIDE; ORGANIC-ACIDS; HYDROUS OXIDE; ADSORPTION; TRANSPORT; DISSOLUTION; SPECIATION; INTERFACE; MIGRATION AB The bacterial consumption of chelating agents that are present in low-level radioactive and mixed wastes may help to immobilize chelated metals and radionuclides accidentally released to groundwater. We investigated the influence of the bacterial consumption of citrate complexed with cobalt on cobalt transport through packed sand columns. Experiments were conducted using each of three types of column packing material using minerals common to subsurface environments: clean quartz sand; ferric oxide (Fe(OH)(3))-coated sand; hausmannite (Mn3O4)-coated sand. Separate control column experiments were conducted to examine citrate's influence on cobalt transport without the bacterial consumption of citrate. The bacterial community consumed all the citrate; the pore water pH decreased by up to one unit before reaching a steady-state value of 6.9-7.1, which was lower than the influent pH (7.4). These results were in contrast to open batch experiments conducted with the same culture, where the pH increased by more than one unit. The dissolved oxygen exhibited similar dynamics, reaching a steady-state value of 3-4 mg/l, well below the influent value of 7.5 mg/l. The dynamics in pore water pH and dissolved oxygen were associated with the presence of the bacterial community because these parameters remained steady in control experiments in which the bacteria were not included. Cobalt transport was most rapid for the columns packed with quartz sand followed by the Fe-coated sand and finally the Mn-coated sand. Most of the cobalt retained by the quartz sand and Fe-coated sand was easily exchanged with Mg2+ whereas most of the cobalt retained by the Mn-coated sand required an acetic acid solution for its removal. The bacterially mediated pH decrease, driven by the consumption of citrate, decreased cobalt sorption to the solid phase resulting in enhanced cobalt transport. The results of these experiments suggest that geochemical changes, driven by the bacterial consumption of citrate, enhanced cobalt transport although the complexing ligand had been removed from the system. (C) 1998 Elsevier Science B.V. ALI rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Virginia, Dept Environm Sci, Program Interdisciplinary Res Contaminant Hydroge, Charlottesville, VA 22903 USA. RP Brooks, SC (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,MS 6038, Oak Ridge, TN 37831 USA. RI Brooks, Scott/B-9439-2012 OI Brooks, Scott/0000-0002-8437-9788 NR 53 TC 11 Z9 12 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD JUL PY 1998 VL 32 IS 1-2 BP 99 EP 115 DI 10.1016/S0169-7722(97)00083-1 PG 17 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA ZV988 UT WOS:000074362500006 ER PT J AU Gao, Y Edgar, JH Chaudhuri, J Cheema, SN Sidorov, MV Braski, DN AF Gao, Y Edgar, JH Chaudhuri, J Cheema, SN Sidorov, MV Braski, DN TI Low-temperature chemical-vapor deposition of 3C-SiC films on Si(100) using SiH4-C2H4-HCl-H-2 SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE 3C-SiC; CVD; crystal growth; epitaxy ID ELECTRICAL-PROPERTIES; BETA AB The benefits of adding HCl on the low-temperature (1000 degrees C) epitaxial growth of 3C-SiC on Si(1 0 0) were examined. At either silicon rich (C/Si < 1) or carbon rich (C/Si > 1) inlet gas ratios, the SiC him composition approached stoichiometry by adding HCl, but only at an inlet C/Si ratio of 1 was the composition of the SIC film approximate 1.0 with a Cl/Si input ratio of 50. The structure of the films improved with the addition of HCl, confirmed by both X-ray diffraction and TEM. For epitaxial films, the FWHM of X-ray diffraction rocking curves decreased to 0.37 degrees or 1348 arcs with increasing Cl/Si to 50 at a C/Si ratio of 1. The him dislocation density was reduced from 1.1 x 10(10) cm(-2) for a 2.0 mu m thick firm for a Cl/Si ratio of 0 to 4.27 x 10(9) cm(-2) for a 0.75 mu m thick film at a Cl/Si ratio of 50. The benefits of adding HCl are attributed to the suppression of pure silicon nucleation and the reduction in growth rate. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Kansas State Univ, Dept Chem Engn, Manhattan, KS 66506 USA. Wichita State Univ, Dept Engn Mech, Wichita, KS 67260 USA. Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Edgar, JH (reprint author), Kansas State Univ, Dept Chem Engn, Durland Hall, Manhattan, KS 66506 USA. RI Chaudhuri, Jharna/E-8863-2013 NR 12 TC 16 Z9 17 U1 1 U2 9 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 JUL PY 1998 VL 191 IS 3 BP 439 EP 445 DI 10.1016/S0022-0248(98)00212-7 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 104TY UT WOS:000075032500018 ER PT J AU Kikuma, J Warwick, T Shin, HJ Zhang, J Tonner, BP AF Kikuma, J Warwick, T Shin, HJ Zhang, J Tonner, BP TI Chemical state analysis of heat-treated polyacrylonitrile fiber using soft X-ray spectromicroscopy SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE NEXAFS; STXM; X-ray microscopy; spectromicroscopy; polyacrylonitrile; heat treatment ID PAN; STABILIZATION; EXCITATION; NEXAFS AB Chemical state analyses of heat-treated polyacrylonitrile (PAN) fibers with a spatial resolution of 200 nm have been performed using scanning transmission X-ray microscopy (STXM) at a third generation synchrotron radiation facility. Near-edge X-ray absorption fine structure (NEXAFS) spectra and chemical state images have been obtained on the cross-sectioned fiber specimens. A clear 'core-rim' structure has been observed in the heat-treated fibers. The spectral characteristics show that the fiber has less nitrile group in the core region, suggesting that, contrary to the model widely believed, the conversion of the nitrile to other chemical species proceeds faster in the core of the fibers. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Asahi Chem Ind Co Ltd, Analyt Res Lab, Fuji, Shizuoka 4168501, Japan. Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Pohang Light Source, Pohang 790784, Kyungbuk, South Korea. Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA. RP Kikuma, J (reprint author), Asahi Chem Ind Co Ltd, Analyt Res Lab, 2-1 Samejima, Fuji, Shizuoka 4168501, Japan. NR 22 TC 18 Z9 21 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD JUL PY 1998 VL 94 IS 3 BP 271 EP 278 DI 10.1016/S0368-2048(98)00196-0 PG 8 WC Spectroscopy SC Spectroscopy GA 106WJ UT WOS:000075173500007 ER PT J AU Cho, HU Hong, J Maeda, T Donovan, SM Abernathy, CR Pearton, SJ Shul, RJ Han, J AF Cho, HU Hong, J Maeda, T Donovan, SM Abernathy, CR Pearton, SJ Shul, RJ Han, J TI High selectivity plasma etching of InN over GaN SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE GaN; InN; selectivity plasma etching ID DRY; NITRIDE AB Etch selectivities for InN over GaN as high as 40 and 100 are achieved in BBr3/Ar and BI3/Ar, respectively, under inductively coupled plasma conditions. Previous work on Cl-2-based plasma chemistries has produced selectivity in the reverse direction, i.e., GaN over InN, and therefore the introduction of these new Br-2- and I-2-based mixtures facilitates device fabrication involving double heterostructures of GaN/InxGa1-xN/GaN. Selectivities up to 10 for InN over the common mask materials SiO2 and SiNx were obtained in both BI3 and BBr3. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Fujitsu Labs Ltd, Kanagawa, Japan. RP Cho, HU (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 14 TC 8 Z9 8 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD JUL PY 1998 VL 27 IS 7 BP 915 EP 917 DI 10.1007/s11664-998-0118-z PG 3 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 101QX UT WOS:000074880600017 ER PT J AU Nakata, T AF Nakata, T TI Reaction of fuel NOx formation for gas turbine conditions SO JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT ASME/JSME/JSES International Solar Energy Conference CY MAR 19-24, 1995 CL MAUI, HAWAII SP ASME, JSME, JSES AB Ammonia contained in coal-gasified fuel is converted to nitrogen oxides (NOx) in the combustion process of a gas turbine in integrated coal gasification combined cycle (IGCC) system. Research data on fuel-NOx formation are insufficient, and there still remains a wide explored domain. The present research aims at obtaining fundamental knowledge of fuel-NOx formation characteristics by applying reaction kinetics to gas turbine conditions. An instantaneous mixing condition was assumed in the cross section of a gas turbine combustor and both gradual mixing condition and instantaneous mixing condition were assumed at secondary air inlet section. The results may be summarized as follows: (1) in the primary combustion zone under fuel rich condition, HCN and other intermediate products are formed as ammonia contained in the fuel decomposes; (2) formation characteristics of fuel-NOx are affected by the condition of secondary air mixing; and (3) the conversion ratio from ammonia to NOx declines as the pressure inside the combustor rises under the condition of gradual miring at the secondary air inlet. These results obtained agreed approximately with the experimentation. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Cent Res Inst Elect Power Ind, Yokosuka 24001, Japan. RP Nakata, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-644, Livermore, CA 94550 USA. RI Nakata, Toshihiko/E-3161-2010 OI Nakata, Toshihiko/0000-0003-0088-9498 NR 19 TC 4 Z9 4 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0742-4795 J9 J ENG GAS TURB POWER JI J. Eng. Gas. Turbines Power-Trans. ASME PD JUL PY 1998 VL 120 IS 3 BP 474 EP 480 DI 10.1115/1.2818169 PG 7 WC Engineering, Mechanical SC Engineering GA 110QZ UT WOS:000075393000007 ER PT J AU Daisey, JM Mahanama, KRR Hodgson, AT AF Daisey, JM Mahanama, KRR Hodgson, AT TI Toxic volatile organic compounds in simulated environmental tobacco smoke: Emission factors for exposure assessment SO JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY LA English DT Article DE air toxics; emission factors; environmental tobacco smoke; volatile organic compounds ID LIQUID-CHROMATOGRAPHY; CHEMICAL-COMPOSITION; INDOOR AIR; NICOTINE; MASS; PARTICLES AB Environmental tobacco smoke (ETS) is suspected to be a major source of exposure to many of the compounds identified as toxic air contaminants. However, we lack emission factors for many of the ETS air toxics for the brands of cigarettes which currently dominate the market and therefore cannot adequately estimate contributions of ETS to such exposures. This study provides up-to-date emission factors for Selected air toxics and other volatile organic compounds (VOCs) in simulated ETS and uses them in a mass balance model to evaluate the potential contribution of ETS to air toxics in indoor air and, therefore to indoor exposures to air toxics. Emission factors (mu g/cigarette) were determined for 21 VOCs (including two aldehydes), nicotine and particulate matter in a room-sized (20-m(3)) environmental chamber with stainless-steel walls, operated under static conditions, using diluted sidestream smoke (no exhaled mainstream smoke) to simulate ETS. Experiments were conducted for Kentucky Reference cigarette 1R4F and for each of six commercial cigarette brands with major market shares. The variabilities in the ETS emission factors among brands of cigarettes were relatively small, ranging from 16 to 31% (expressed as the coefficient of variation) among the six brands. The concentrations of most of the VOCs did not change over the 4-hour periods of the experiments. However concentrations of 3-ethenylpyridine, phenol, o-cresol and m,p-cresol showed consistent decreases over time, indicating removal by means other than the very low air infiltration rate (0.03 h(-1)), e.g., deposition onto the chamber surfaces. Emission factors for these compounds were calculated to take these losses into account and the rate constants for these losses were estimated. To estimate indoor concentrations and inhalation exposures to 16 VOCs, nicotine and PM-2.5, the average emission factors for the six commercial brands were used in a time-dependent mass-balance model for two scenarios: a typical office building and art average residence. In general, the indoor concentrations of the air toxics from ETS, under conditions selected to be "typical" rather than extreme, are comparable in magnitude to average outdoor concentrations, indicating that ETS can be a significant contributor to the total indoor concentration and the inhalation exposure for these species. At higher smoking rates, exposures To VOCs from ETS could be several times higher than those modeled under more "typical" conditions. C1 Lawrence Berkeley Natl Lab, Div Energy & Environm, Indoor Environm Program, Berkeley, CA 94720 USA. RP Daisey, JM (reprint author), Lawrence Berkeley Natl Lab, Div Energy & Environm, Indoor Environm Program, Berkeley, CA 94720 USA. EM jmdaisey@lbl.gov FU NHLBI NIH HHS [R01-HL42490] NR 47 TC 50 Z9 51 U1 0 U2 4 PU PRINCETON SCIENTIFIC PUBL INC PI PRINCETON PA PO BOX 2155, PRINCETON, NJ 08543 USA SN 1053-4245 J9 J EXPO ANAL ENV EPID JI J. Expo. Anal. Environ. Epidemiol. PD JUL-SEP PY 1998 VL 8 IS 3 BP 313 EP 334 PG 22 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 100GL UT WOS:000074807800003 PM 9679214 ER PT J AU Tsuruta, H Irving, TC Taylor, SR AF Tsuruta, H Irving, TC Taylor, SR TI Activity-dependent changes of lattice spacings in frog skeletal muscle SO JOURNAL OF GENERAL PHYSIOLOGY LA English DT Meeting Abstract C1 Mayo Clin & Mayo Fdn, Dept Pharmacol, Rochester, MN 55905 USA. IIT, Div Biol, Chicago, IL 60616 USA. Stanford Univ, SSRL, Stanford, CA 94305 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ROCKEFELLER UNIV PRESS PI NEW YORK PA 1114 FIRST AVE, 4TH FL, NEW YORK, NY 10021 USA SN 0022-1295 J9 J GEN PHYSIOL JI J. Gen. Physiol. PD JUL PY 1998 VL 112 IS 1 MA 33 BP 14A EP 14A PG 1 WC Physiology SC Physiology GA ZZ047 UT WOS:000074690300040 ER PT J AU Aschieri, P Castellani, L AF Aschieri, P Castellani, L TI Universal enveloping algebra and differential calculi on inhomogeneous orthogonal q-groups SO JOURNAL OF GEOMETRY AND PHYSICS LA English DT Article DE multiparametric quantum groups; universal enveloping algebra; Hopf algebra; bimodules ID QUANTUM GROUPS; GRAVITY; FIELDS; GL(N) AB We review the construction of the multiparametric quantum group ISOq,r(N) as a projection from SOq,r(N + 2) and show that it is a bicovariant bimodule over SOq,r(N). The universal enveloping algebra U-q,U-r(iso(N)), characterized as the Hopf algebra of regular functionals on ISOq,r(N), is found as a Hopf subalgebra of U-q,U-r(so(N + 2)) and is shown to be a bicovariant bimodule over U-q,U-r(so(N)). An R-matrix formulation of U-q,U-r(iso(N)) is given and we prove the pairing U-q,U-r(iso(N)) <-> ISOq,r(N). We analyze the subspaces of U-q,U-r(iso(N)) that define bicovariant differential calculi on ISOq,r(N). C1 Univ Turin, Dipartimento Fis Teor, Fac Sci Matemat 2, Dipartimento Sci & Tecnol Avanzate, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Castellani, L (reprint author), Univ Turin, Dipartimento Fis Teor, Fac Sci Matemat 2, Dipartimento Sci & Tecnol Avanzate, Via P Giuria 1, I-10125 Turin, Italy. EM aschieri@theor3.lbl.gov; castellani@to.infn.it RI Aschieri, Paolo/J-2965-2012; OI Castellani, Leonardo/0000-0002-7954-5622 NR 32 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0393-0440 J9 J GEOM PHYS JI J. Geom. Phys. PD JUL PY 1998 VL 26 IS 3-4 BP 247 EP 271 DI 10.1016/S0393-0440(97)00045-4 PG 25 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA ZX412 UT WOS:000074513200004 ER PT J AU Feldman, WC Barraclough, BL Gosling, JT McComas, DJ Riley, P Goldstein, BE Balogh, A AF Feldman, WC Barraclough, BL Gosling, JT McComas, DJ Riley, P Goldstein, BE Balogh, A TI Ion energy equation for the high-speed solar wind: Ulysses observations SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HEAT-FLUX; PLASMA; PARAMETERS; HEMISPHERES; TURBULENCE; ELECTRONS; NORTHERN; SOUTHERN; FIELD; WAVES AB Ulysses data in the high-speed solar wind that cover a wide range of latitudes centered on the solar poles were studied to test whether a polytrope law can be used to close the ion energy equation. Three approaches were taken, We determined the correlation between proton temperature and density (1) in the free expansion of the highspeed solar wind between 1.5 and 4.8 AU, (2) in steepened microstreams at high latitudes, and (3) at the edges of the equatorial band of solar wind variability. Strong correlations were observed in all data subsets that are consistent with a single polytrope relation, T(p) = aN(p)((gamma*-1)), where our best estimate gamma* is between 1.5 and 1.7. The best fitting relation T(p) = (2.0 +/- 0.13) x 10(5) N(p)(0.57). C1 Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87544 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London, England. RP Feldman, WC (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci Grp, Mail Stop D466, Los Alamos, NM 87544 USA. EM wfeldman@lanl.gov NR 36 TC 18 Z9 18 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JUL 1 PY 1998 VL 103 IS A7 BP 14547 EP 14557 DI 10.1029/98JA00963 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZY130 UT WOS:000074589300004 ER PT J AU Gary, SP Newbury, JA Goldstein, BE AF Gary, SP Newbury, JA Goldstein, BE TI Lower bound for electron core beta in the solar wind SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID PLASMA DEPLETION LAYER; EARTHS MAGNETOSHEATH; HEAT-FLUX; ION; INSTABILITIES; ULYSSES; TEMPERATURE; ANISOTROPY AB Solar wind electrons, especially under conditions of relatively low speed flow, often can be represented as two bi-Maxwellian components, a cooler, more dense core (denoted by the subscript c) and a hotter, more tenuous halo. Solar wind observations from Ulysses between 1.5 and 2 AU further indicate that the beta for electron core temperatures parallel to the background magnetic field, beta(parallel to c) has a distinct lower bound near 0.1. To seek the cause of this possible constraint, numerical solutions of the full Vlasov linear dispersion equation are used for four heat flux instabilities under a core/halo model with parameters representative of the solar wind near 1 AU. In this model the whistler heat flux instability is the growing mode of lowest threshold at most observed values beta(parallel to c). As beta(parallel to c) decreased, however, the growth of this c mode is reduced, so that at entry small values of this parameter the Alfven heat flux instability or the electron/ion acoustic instability becomes the fastest growing mode. The critical condition corresponding to this transition is calculated as a function of T-parallel to c/T-p (where T-p is the proton temperature) and approximately corresponds to the observed constraint at beta(parallel to c) similar or equal to 0.1. The Alfven and ion acoustic instabilities both resonate with core electrons; the hypothesis is proposed that core beating by these two modes at the critical condition establishes a lower bound on beta(parallel to c). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. RP Gary, SP (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. EM pgary@lanl.gov; newbury@igpp.ucla.edu; bgoldstein@jplsp.jpl.nasa.gov NR 27 TC 7 Z9 7 U1 0 U2 1 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 JUL 1 PY 1998 VL 103 IS A7 BP 14559 EP 14566 DI 10.1029/98JA01172 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZY130 UT WOS:000074589300005 ER PT J AU Gary, SP Li, H O'Rourke, S Winske, D AF Gary, SP Li, H O'Rourke, S Winske, D TI Proton resonant firehose instability: Temperature anisotropy and fluctuating field constraints SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CYCLOTRON INSTABILITY; HOSE INSTABILITY; MAGNETIC-FIELD; PLASMA; MAGNETOSHEATH; DEPLETION; PRESSURE; BETA AB The electromagnetic proton firehose instability may grow in a plasma if the proton velocity distribution is approximately bi-Maxwellian and T-parallel to p > T-perpendicular to p, where the directional subscripts denote directions relative to the background magnetic field. Linear Vlasov dispersion theory in a homogeneous electron-proton plasma implies an instability threshold condition at constant maximum growth rate l-T-perpendicular to p/T-parallel to p = S-p/beta(parallel to p)(alpha p) over 1 < beta(parallel to p) less than or equal to 10 where beta(parallel to p) = 8 pi n(p)T(parallel to p)/B-0(2) and B-0 is the background magnetic field. Here S-p and alpha(p) are fitting parameters and alpha(p) similar or equal to 0.7. One- and two-dimensional initial value hybrid simulations of this growing mode are carried out under proton cyclotron resonant conditions in a homogeneous plasma on the initial domain 2 less than or similar to beta(parallel to p) less than or equal to 100. The two-dimensional simulations show that enhanced fluctuations from this instability impose a bound on the proton temperature anisotropy of the form of the above equation with the fluid theory result alpha(p) similar or equal to 1.0. On this domain both one- and two-dimensional simulations yield a new form for the upper bound on the fluctuating field energy density from the proton resonant firehose instability /delta B/(2) / B-0(2) = S-B + alpha(B)ln (beta(parallel to p)) where S-B and alpha(B) are empirical parameters which are functions of the initial growth rate. This logarithmic behavior is qualitatively different from a fluid theory prediction and, like the anisotropy bound, should be subject to observational verification in any sufficiently homogeneous plasma in which the proton velocity distribution is approximately bi-Maxwellian. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Gary, SP (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. NR 29 TC 71 Z9 71 U1 0 U2 1 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 JUL 1 PY 1998 VL 103 IS A7 BP 14567 EP 14574 DI 10.1029/98JA01174 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZY130 UT WOS:000074589300006 ER PT J AU Mora, CJ AF Mora, CJ TI Bridging the Cold War and the twenty-first century: Chronicling the history of Sandia National Laboratories SO JOURNAL OF GOVERNMENT INFORMATION LA English DT Article; Proceedings Paper CT Annual Meeting of the Society-for-History-in-the-Federal-Government and the National Archives Assembly CY APR 03-04, 1997 CL COLLEGE PK, MARYLAND SP Soc Hist Fed Govt DE history of Sandia National Laboratories; nuclear weapons; US Department of Energy History; history of the Cold War; archives; history of US National Laboratories AB Sandia National Laboratories, located in Albuquerque, New Mexico, was originally a part of Los Alamos Laboratory. In 1949, AT&T agreed to manage Sandia, which they did for the next 44 years. During those Cold War years, Sandia was the prime weapons engineering laboratory for Los Alamos and Lawrence Livermore. As such, it bore prime responsibility for designing and adapting nuclear weapons for the military services' delivery systems, and ensuring the safety and reliability of the stockpile. The Labs' history has been unevenly documented, hindered by the secret nature of its work and the desire of management to maintain a low public profile. There have been three history programs at Sandia: a restricted history published internally in 1963, another history program in the early 1980s that resulted in a history of the Labs' first decade; and the current history program dating from the mid-1990s, which has published a general history and several monographs. This article discusses the challenges and problems inherent in documenting the history of a national weapons laboratory during the last 50 years. (C) 1998 Elsevier Science Ltd. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Albuquerque, NM 87131 USA. RP Mora, CJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 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 1352-0237 J9 J GOV INFORM JI J. Gov. Inf. PD JUL-AUG PY 1998 VL 25 IS 4 BP 321 EP 330 DI 10.1016/S1352-0237(98)00012-4 PG 10 WC Information Science & Library Science SC Information Science & Library Science GA 112WQ UT WOS:000075518000001 ER PT J AU Alvin, KF Peterson, LD AF Alvin, KF Peterson, LD TI Determination of modal residues and residual flexibility for time-domain system realization SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID IDENTIFICATION; ALGORITHM AB A linear least-squares procedure for the determination of modal residues using time-domain system realization theory is presented.The present procedure is intended to complement existing techniques for time-domain system identification and is shown to be theoretically equivalent to residue determination in realization algorithms such as the eigensystem realization algorithm and e-Markov covariance equivalent realization method. However, isolating the optimal residue estimation problem from the general realization problem affords several alternative strategies as compared to standard realization algorithms for structural dynamics identification. Primary among these are alternative techniques for handling data sets with large numbers of sensors using small numbers of reference point responses and the inclusion of terms that accurately model the effects of residual flexibility. The accuracy and efficiency of the present realization theory-based procedure is demonstrated for both simulated and experimental data. C1 Sandia Natl Labs, Dept 9234, Albuquerque, NM 87185 USA. Univ Colorado, Dept Aerosp Engn, Boulder, CO 80309 USA. RP Alvin, KF (reprint author), Sandia Natl Labs, Dept 9234, POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD JUL-AUG PY 1998 VL 21 IS 4 BP 588 EP 594 PG 7 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA ZZ102 UT WOS:000074695900009 ER PT J AU Jones, AG Stockwell, CA Walker, D Avise, JC AF Jones, AG Stockwell, CA Walker, D Avise, JC TI The molecular basis of a microsatellite null allele from the white sands pupfish SO JOURNAL OF HEREDITY LA English DT Article ID GENETIC-RELATIONSHIPS; MARKERS; POPULATION; PARENTAGE; LOCI AB Microsatellite loci were cloned and characterized from the White Sands pupfish (Cyprinodon tularosa), a New Mexico state-listed endangered species. One locus exhibited a high-frequency nonamplifying allele localized to a single population. This null allele was PCR amplified by redesign of one of the original primers and multiple individuals homozygous for null as well as for nonnull alleles were sequenced using the new primer. These molecular dissections revealed that the original failure to amplify some alleles from this microsatellite locus was due to a 4 bp deletion in one of the original PCR priming sites. Furthermore, the reamplifications revealed five distinct size classes of alleles that had been masquerading as the original null. These null alleles did not overlap in length with the nonnull alleles, and they also differed consistently by a linked nucleotide substitution. Results suggest that the original null allele (as well as the nonnull class) has diversified considerably since its origin and has not recombined frequently with the nonnull class of alleles. C1 Univ Georgia, Dept Genet, Athens, GA 30602 USA. Savannah River Ecol Lab, Aiken, SC USA. RP Avise, JC (reprint author), Univ Georgia, Dept Genet, Athens, GA 30602 USA. NR 16 TC 61 Z9 78 U1 0 U2 4 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 0022-1503 J9 J HERED JI J. Hered. PD JUL-AUG PY 1998 VL 89 IS 4 BP 339 EP 342 DI 10.1093/jhered/89.4.339 PG 4 WC Evolutionary Biology; Genetics & Heredity SC Evolutionary Biology; Genetics & Heredity GA 106YF UT WOS:000075178500010 ER PT J AU Coriano, C Li, HN Savkli, C AF Coriano, C Li, HN Savkli, C TI Exclusive processes at intermediate energy, quark-hadron duality and the transition to perturbative QCD SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE QCD; sum rules ID PION FORM-FACTOR; LARGE-MOMENTUM-TRANSFER; SUM-RULES; COMPTON-SCATTERING; QUANTUM-CHROMODYNAMICS; ASYMPTOTIC-BEHAVIOR; RESONANCE PHYSICS; TRANSVERSE-MOMENTUM; SUDAKOV SUPPRESSION; ELECTROPRODUCTION AB Experiments at CEBAF will scan the intermediate-energy region of the QCD dynamics for the nucleon form factors and for Compton Scattering. These experiments will definitely clarify the role of resummed perturbation theory and of quark-hadron duality (QCD sum rules) in this regime. With this perspective in mind, we review the factorization theorem of perturbative QCD for exclusive processes at intermediate energy scales, which embodies the transverse degrees of freedom of a parton and the Sudakov resummation of the corresponding large logarithms. We concentrate on the pion and proton electromagnetic form factors and on pion Compton scattering. New ingredients, such as the evolution of the pion wave function and the complete two-loop expression of the Sudakov factor, are included. The sensitivity of our predictions to the infrared cutoff for the Sudakov evolution is discussed. We also elaborate on QCD sum rule methods for Compton Scattering, which provide an alternative description of this process. We show that, by comparing the local duality analysis to resummed perturbation theory, it is possible to describe the transition of exclusive processes to perturbative QCD. C1 Jefferson Lab, Theory Grp, Newport News, VA 23606 USA. Natl Cheng Kung Univ, Dept Phys, Tainan 70101, Taiwan. Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. RP Coriano, C (reprint author), Jefferson Lab, Theory Grp, Newport News, VA 23606 USA. EM coriano@jlab.org; hnli@mail.ncku.edu.tw; csavkli@physics.wm.edu OI Coriano', Claudio/0000-0003-0479-8075 NR 71 TC 6 Z9 6 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD JUL PY 1998 IS 7 AR 008 PG 51 WC Physics, Particles & Fields SC Physics GA 124DB UT WOS:000076165100008 ER PT J AU Rosenthal, DS Simbulan-Rosenthal, CMG Iyer, S Spoonde, A Smith, W Ray, R Smulson, ME AF Rosenthal, DS Simbulan-Rosenthal, CMG Iyer, S Spoonde, A Smith, W Ray, R Smulson, ME TI Sulfur mustard induces markers of terminal differentiation and apoptosis in keratinocytes via a Ca2+-calmodulin and caspase-dependent pathway SO JOURNAL OF INVESTIGATIVE DERMATOLOGY LA English DT Article DE BAPTA; caspase-3; poly(ADP-ribose) polymerase; W-7 ID EXTRACELLULAR CALCIUM CONCENTRATIONS; INTRACELLULAR FREE CALCIUM; PROTEIN-KINASE-C; POLY(ADP-RIBOSE) POLYMERASE; GRANZYME-B; DNA FRAGMENTATION; CELL-DEATH; IN-VITRO; CALMODULIN ANTAGONISTS; MURINE KERATINOCYTES AB Sulfur mustard (SM) induces vesication via poorly understood pathways. The blisters that are formed result primarily from the detachment of the epidermis from the dermis at the level of the basement membrane. In addition, there is toxicity to the basal cells, although no careful study has been performed to determine the precise mode of cell death biochemically. We describe here two potential mechanisms by which SM causes basal cell death and detachment: namely, induction of terminal differentiation and apoptosis. In the presence of 100 mu M SM, terminal differentiation was rapidly induced in primary human keratinocytes that included the expression of the differentiation-specific markers K1 and K10 and the cross-linking of the cornified envelope precursor protein involucrin. The expression of the attachment protein, fibronectin, was also reduced in a time- and dose-dependent fashion. features common to both differentiation and apoptosis were also induced in 100 mu M SM, including the rapid induction of p53 and the reduction of Bcl-2. At higher concentrations of SM (i.e., 300 mu M), formation of the characteristic nucleosome-sized DNA ladders, TUNEL-positive staining of cells, activation of the cysteine protease caspase-3/apopain, and cleavage of the death substrate poly(ADP-ribose) polymerase, were observed both in vivo and in vitro. Both the differentiation and the apoptotic processes appeared to be calmodulin dependent, because the calmodulin inhibitor W-7 blocked the expression of the differentiation-specific markers, as well as the apoptotic response in a concentration-dependent fashion. In addition, the intracellular Ca2+ chelator, BAPTA-AM, blocked the differentiation response and attenuated the apoptotic response. These results suggest a strategy for designing inhibitors of SM vesication via the Ca2+-calmodulin or caspase-3/PARP pathway. C1 Georgetown Univ, Sch Med, Dept Biochem & Mol Biol, Washington, DC 20007 USA. Pacific NW Natl Lab, Richland, WA USA. USA, Med Res Inst Chem Def, Aberdeen Proving Ground, MD 21010 USA. RP Rosenthal, DS (reprint author), Georgetown Univ, Sch Med, Dept Biochem & Mol Biol, 3900 Reservoir Rd NW, Washington, DC 20007 USA. NR 65 TC 77 Z9 79 U1 0 U2 5 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0022-202X J9 J INVEST DERMATOL JI J. Invest. Dermatol. PD JUL PY 1998 VL 111 IS 1 BP 64 EP 71 DI 10.1046/j.1523-1747.1998.00250.x PG 8 WC Dermatology SC Dermatology GA ZW467 UT WOS:000074413900010 PM 9665388 ER PT J AU Pathare, PM Hamlin, DK Wilbur, DS Brechbiel, MW Bray, LA AF Pathare, PM Hamlin, DK Wilbur, DS Brechbiel, MW Bray, LA TI Synthesis and radiolabeling of a biotin-CHX-B chelate for Bi-213 SO JOURNAL OF LABELLED COMPOUNDS & RADIOPHARMACEUTICALS LA English DT Article DE bismuth-213; biotin derivative; pretargeting; radioimmunotherapy ID PARTICLE-MEDIATED RADIOIMMUNOTHERAPY; MONOCLONAL-ANTIBODY; EMITTING RADIONUCLIDES; AVIDIN; STREPTAVIDIN; SYSTEM AB The synthesis and radiolabeling of a biotin derivative which contains a chelating group (CHX-B) for binding the alpha-emitting radionuclide, Bi-213, is described. The biotin-CHX-B derivative was readily prepared in high yield through a convergent synthesis that coupled N-methylglycylbiotinamide with anilino-CHX-B. Bismuth-213 labeling of the biotin-CHX-B molecule was facile at room temperature, resulting in >95 % radiochemical yield within 10 min reaction time. C1 Univ Washington, Dept Radiat Oncol, Seattle, WA 98195 USA. NCI, Radiat Oncol Branch, NIH, Bethesda, MD 20892 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Pathare, PM (reprint author), Univ Washington, Dept Radiat Oncol, Seattle, WA 98195 USA. NR 24 TC 2 Z9 2 U1 1 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0362-4803 J9 J LABELLED COMPD RAD JI J. Label. Compd. Radiopharm. PD JUL PY 1998 VL 41 IS 7 BP 595 EP 603 DI 10.1002/(SICI)1099-1344(199807)41:7<595::AID-JLCR116>3.0.CO;2-O PG 9 WC Biochemical Research Methods; Chemistry, Medicinal; Chemistry, Analytical SC Biochemistry & Molecular Biology; Pharmacology & Pharmacy; Chemistry GA ZY753 UT WOS:000074655900003 ER PT J AU Murdoch, KM Nguyen, AD Edelstein, NM AF Murdoch, KM Nguyen, AD Edelstein, NM TI One- and two-photon spectroscopy of Eu3+ in LuPO4 SO JOURNAL OF LUMINESCENCE LA English DT Article DE two-photon absorption; polarization analysis; crystal-field analysis ID 2-PHOTON ABSORPTION-SPECTROSCOPY; POLARIZATION DEPENDENCE; INTENSITIES; TRANSITION; CRYSTALS; LINES; SM-2+; YPO4; CM3+ AB One-photon laser excitation and fluorescence spectra have been recorded for the Eu3+ ion diluted in single crystals of LuPO4. Analysis of these spectra resulted in the assignment of 23 energy levels of the F-7(J) and D-5(J) multiplets, which were fitted to the parameters of an empirical Hamiltonian with an rms deviation of 8.7 cm(-1). The intensities of the two-photon absorption transitions to the D-5(0) and D-5(2) multiplets have been investigated. The polarization dependences of transitions to all five of the crystal-field levels were measured and are compared with theoretical predictions. The intensity model included the third-order spin-orbit interaction. Good agreement was found for three of the five transitions observed. However, the polarization dependences of the other two did not agree with the predicted behavior, as they exhibited an additional isotropic component. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, MS 70A-1150, Berkeley, CA 94720 USA. EM murdoch@chem.wisc.edu NR 29 TC 4 Z9 4 U1 3 U2 8 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 JUL PY 1998 VL 79 IS 1 BP 55 EP 64 DI 10.1016/S0022-2313(98)00014-3 PG 10 WC Optics SC Optics GA 111QD UT WOS:000075448400007 ER PT J AU Javorsky, P Nakotte, H Robinson, RA Kelley, TM AF Javorsky, P Nakotte, H Robinson, RA Kelley, TM TI Crystal field in ErNiAl studied by inelastic neutron scattering SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE neutron scattering; rare-earth intermetallic compounds; crystal field; heat capacities AB We present an inelastic neutron scattering study of the crystal field in the ErNiAl intermetallic compound. The results are compared with the specific heat data and the lower portion of the crystal-field energy level scheme was determined. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Charles Univ, Dept Met Phys, CR-12116 Prague 2, Czech Republic. Univ Calif Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. RP Javorsky, P (reprint author), Charles Univ, Dept Met Phys, KE Karlovu 5, CR-12116 Prague 2, Czech Republic. EM javor@mag.mff.cuni.cz RI Javorsky, Pavel/C-2132-2015 NR 10 TC 4 Z9 4 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 JUL PY 1998 VL 186 IS 3 BP 373 EP 376 DI 10.1016/S0304-8853(98)00101-2 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA ZX370 UT WOS:000074508700013 ER PT J AU Gibbons, MR AF Gibbons, MR TI Micromagnetic simulation using the dynamic alternating direction implicit method SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE micromagnetic simulation; spin-valves; magnetoresistive head simulation ID SPIN-VALVE SENSORS; GIANT MAGNETORESISTANCE; DOMAIN-WALLS; EXCHANGE; HEADS AB We have developed a 3-D micromagnetic algorithm using finite-differences and the iterative matrix solution method, dynamic alternating direction implicit (DADI), for the magnetostatic potential equation. As in previous work, the magnetization is integrated in time toward equilibrium with the Landau-Lifshitz-Gilbert (LLG) equation. We have found that only one iteration of DADI is needed for each time step of the LLG equation. The resulting algorithm has relatively short computation times even for simulations with linearly permeable structures of various shapes. In addition to the magnetostatic field the effective H-field includes exchange coupling, crystalline anisotropy, interlayer exchange coupling, and current-induced fields allowing the simulation of a wide range of devices. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Gibbons, MR (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave,L-395,POB 808, Livermore, CA 94550 USA. NR 32 TC 24 Z9 24 U1 0 U2 2 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 JUL PY 1998 VL 186 IS 3 BP 389 EP 401 DI 10.1016/S0304-8853(98)00105-X PG 13 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA ZX370 UT WOS:000074508700017 ER PT J AU Galkin, VY Ortiz, WA Fishman, RS AF Galkin, VY Ortiz, WA Fishman, RS TI Local Fe moment in commensurate and incommensurate spin-density wave Cr matrix SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Letter DE spin-density wave; paramagnetism; antiferromagnetism; Cr alloys ID IMPURITY RESONANCE SCATTERING; MAGNETIC PHASE-DIAGRAMS; TERNARY ALLOYS; CHROMIUM; ANTIFERROMAGNETISM; TEMPERATURE; MN AB It is well known that Fe is the only impurity atom which exhibits Pauli paramagnetism below the Neel temperature of a dilutely doped Cr host. Magnetic measurements on two complementary Cr alloys now reveal that the Fe moment is about 6% larger in the incommensurate than in the commensurate spin-density wave state. A phenomenological model is presented which explains this difference by dividing the Fe moment into bound and unbound parts. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Fed Sao Carlos, Dept Fis, BR-13560 Sao Carlos, SP, Brazil. RP Fishman, RS (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Fishman, Randy/C-8639-2013; Ortiz, Wilson/K-7379-2012 NR 18 TC 3 Z9 3 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 JUL PY 1998 VL 186 IS 1-2 BP L1 EP L6 DI 10.1016/S0304-8853(98)00100-0 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA ZV938 UT WOS:000074357300001 ER PT J AU Stephenson, JL McLuckey, SA AF Stephenson, JL McLuckey, SA TI Charge manipulation for improved mass determination of high-mass species and mixture components by electrospray mass spectrometry SO JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electrospray mass spectrometry; multiply charged ions; ion-ion reactions, quadrupole ion trap; transformation algorithms ID PROTON-TRANSFER REACTIONS; ION-MOLECULE REACTIONS; GAS-PHASE; IONIZATION; DECONVOLUTION; PRINCIPLES; PROTEINS; SPECTRA AB The manipulation of the charge states of high-mass ions can facilitate mass determination in electrospray (ES) mass spectrometry. Specifically, the reduction of charge (which leads to ions of higher mass-to-charge ratios) can significantly reduce peak overlap. Signals associated with various charge states of high-mass ions are more easily resolved at low charge states and chemical noise tends to be significantly lower at high mass-to-charge ratios than in the normal mass-to-charge window typically associated with electrospray. Algorithms that transform ES mass spectra to zero-charge spectra are most likely to yield unambiguous results when charge states are clearly resolved and when signal-to-noise ratios are relatively high. Charge manipulation can enhance the value of the transformation algorithms in cases in which compromises their utility. Such situations include ES mass spectra of high-mass species that yield charge states that are not baseline resolved, mixtures with many components and mixtures in which the signals from major components overwhelm signals from minor components. Examples of improved mass determination are illustrated for proteins using ion-ion chemistry as the means for charge state manipulation and the quadrupole ion trap as the mass analyzer. (C) 1998 John Wiley & Sons, Ltd. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP McLuckey, SA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Stephenson, James/A-9262-2009; McLuckey, Scott/B-2203-2009 OI McLuckey, Scott/0000-0002-1648-5570 NR 27 TC 44 Z9 44 U1 0 U2 8 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1076-5174 J9 J MASS SPECTROM JI J. Mass Spectrom. PD JUL PY 1998 VL 33 IS 7 BP 664 EP 672 DI 10.1002/(SICI)1096-9888(199807)33:7<664::AID-JMS663>3.0.CO;2-P PG 9 WC Biophysics; Chemistry, Organic; Spectroscopy SC Biophysics; Chemistry; Spectroscopy GA 102VJ UT WOS:000074945900011 PM 9692249 ER PT J AU Aselage, TL AF Aselage, TL TI The coexistence of silicon borides with boron-saturated silicon: Metastability of SiB3 SO JOURNAL OF MATERIALS RESEARCH LA English DT Article AB The silicon-rich end of the Si-B phase diagram, defining the silicon boride(s) that coexist in equilibrium with boron-saturated silicon, is poorly known. Understanding this equilibrium has implications for the processing of p(+) silicon wafers, whose boron concentrations are near the solubility limit. Additionally, silicon boride precipitates produced by boron-ion-implantation and annealing of crystalline silicon have recently been shown to be efficient internal getters of transition metal ions. The experiments described in this paper probe the stability of these silicon borides. A phase with a boron-carbide-like structure. SiB3, grows from boron-saturated silicon in both the solid and the liquid state. However, SiB3 is not found to be stable in either circumstance. Rather, SiB3 is a metastable phase whose formation is driven by the relative ease of its nucleation and growth. The silicon boride that exists in stable equilibrium with boron-saturated silicon is SiB6.A qualitative understanding of the metastability of SiB3 comes from recognizing the conflict between the bonding requirements of icosahedral borides such as SiB3 and the size mismatch between silicon and boron atoms. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Aselage, TL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 40 TC 26 Z9 28 U1 2 U2 19 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 JUL PY 1998 VL 13 IS 7 BP 1786 EP 1794 DI 10.1557/JMR.1998.0252 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA ZX311 UT WOS:000074502800013 ER PT J AU Indacochea, JE Bloom, I Krumpelt, M Benjamin, TG AF Indacochea, JE Bloom, I Krumpelt, M Benjamin, TG TI A comparison of two aluminizing methods for corrosion protection in the wet seal of molten carbonate fuel cells SO JOURNAL OF MATERIALS RESEARCH LA English DT Article AB The corrosion behavior of aluminized Type 310S stainless steel (SS) in the wet seal of molten carbonate fuel cells was investigated. Coupons of Type 310S SS were aluminized by two different aluminizing methods: thermal spray and slurry-coating. In both types of samples Fe and Cr diffused readily into the Al layer at 650 degrees C. At first this interdiffusion is limited to the interfacial area. With time, Fe and Cr aluminides precipitate in the Al layer. The slurry-coated layer contains a higher concentration of FeAl and Fe3Al than does the thermal spray layer. Consequently, the slurry-coated layer also displays a greater degree of corrosion than the thermal spray layer. C1 Argonne Natl Lab, Electrochem Technol Program, Argonne, IL 60439 USA. MC Power Corp, Burr Ridge, IL 60521 USA. RP Bloom, I (reprint author), Argonne Natl Lab, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 7 Z9 8 U1 0 U2 3 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 JUL PY 1998 VL 13 IS 7 BP 1834 EP 1839 DI 10.1557/JMR.1998.0260 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA ZX311 UT WOS:000074502800021 ER PT J AU Chen, SP AF Chen, SP TI Compositional and physical changes on perovskite crystal surfaces SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID THIN-FILMS; RELAXATION; OXIDES; NIO AB The surface composition of BaTiO3, SrTiO3, and CaTiO3 perovskite(100) surface is determined by shell-model calculations. The TiO2-terminaled surface is energetically favorable for BaTiO3 and SrTiO3, which is consistent with experimental observations on SrTiO3. On the other hand, the CaO-terminated surface is preferred for CaTiO3 where Ca2+ is the smallest 2+ cation in these titanates. Ions on (100) surface rumple and induce surface dipoles. The surface ferroelectric polarization stabilizes the surface and changes its sign as the surface composition changes from TiO2 to CaO. This phenomenon is expected to affect the stability and properties of epitaxial films on perovskite substrates. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Chen, SP (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 21 TC 16 Z9 17 U1 0 U2 3 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 JUL PY 1998 VL 13 IS 7 BP 1848 EP 1852 DI 10.1557/JMR.1998.0262 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA ZX311 UT WOS:000074502800023 ER PT J AU Gao, Y Kim, YJ Chambers, SA AF Gao, Y Kim, YJ Chambers, SA TI Preparation and characterization of epitaxial iron oxide films SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID MOLECULAR-BEAM EPITAXY; SCANNING-TUNNELING-MICROSCOPY; ENERGY-ELECTRON-DIFFRACTION; SURFACE-STRUCTURE; FE3O4 FILMS; DEFECT STRUCTURE; WUSTITE PHASE; THIN-FILMS; GROWTH; PT(111) AB Well-ordered, pure-phase epitaxial films of FeO, Fe3O4, and gamma-Fe2O3 were prepared on MgO(001) by oxygen-plasma-assisted MBE. The stoichiometries of these thin films were controlled by varying the growth rate and oxygen partial pressure. Selective growth of gamma-Fe2O3 and alpha-Fe2O3 was achieved by controlling the growth conditions in conjunction with the choice of appropriate substrates. Growth of the iron oxide epitaxial films on MgO at greater than or equal to 350 degrees C is accompanied by significant Mg outdiffusion. The FeO(001) film surface exhibits a (2 x 2) reconstruction, which is accompanied by a significant amount of Fe3+ in the surface region. Fe3O4(001) has been found to reconstruct to a (root 2 x root 2)R45 degrees structure. gamma-Fe2O3(001) film surface is unreconstructed. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Gao, Y (reprint author), Pacific NW Lab, POB 999,MS K8-93, Richland, WA 99352 USA. NR 40 TC 43 Z9 43 U1 1 U2 33 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 JUL PY 1998 VL 13 IS 7 BP 2003 EP 2014 DI 10.1557/JMR.1998.0281 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA ZX311 UT WOS:000074502800042 ER PT J AU Haridoss, P Uribe, FA Garzon, FH Zawodzinski, TA AF Haridoss, P Uribe, FA Garzon, FH Zawodzinski, TA TI Structural modifications of disordered mesocarbon microbeads with lower temperatures of heat treatment SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CHARGE-DISCHARGE CHARACTERISTICS; LITHIUM; CARBON; GRAPHITE; INTERCALATION; ELECTRODES; BATTERIES; FIBER; CELLS AB We describe the variation of structural and physical properties of mesocarbon microbeads, a potential anode material for rechargeable lithium batteries, as a function of heat-treatment temperature in the range 400-1100 degrees C. Scanning electron microscopy (SEM) studies indicated changes in the morphology of the mesocarbons with heat treatment. X-ray studies show that average crystallite size varies considerably with heat treatment. The d(002) spacing decreases with increasing heat-treatment temperatures. The electronic conductivity of the mesocarbon microbeads also increases substantially with increasing heat-treatment temperature. Eased on thermogravimetric analysis (TGA) and other measurements, we find that organic fractions volatilizes out of these carbons in two distinct stages. The observed weight loss correlates with the structural changes observed. We suggest that these observations are consistent with two types of hydrogenated fractions present in the "green" mesocarbons. C1 Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Haridoss, P (reprint author), Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, POB 1663, Los Alamos, NM 87545 USA. NR 22 TC 7 Z9 7 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 JUL PY 1998 VL 13 IS 7 BP 2015 EP 2022 DI 10.1557/JMR.1998.0282 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA ZX311 UT WOS:000074502800043 ER PT J AU Nakashima, K Makino, T Mori, K Glaeser, AM AF Nakashima, K Makino, T Mori, K Glaeser, AM TI Wettability and interfacial reaction between alumina and Cu-based alloys SO JOURNAL OF MATERIALS SYNTHESIS AND PROCESSING LA English DT Article DE PTLP bonding; alumina; wettability; Cu-based alloy AB In PTLP (partial transient liquid-phase) bonding, the transient liquid phase is sandwiched between a ceramic and a refractory core metal. A transient liquid phase chemistry that reduces the contact angle on the ceramic is necessary to improve strength characteristics. in this study, the effect of additions on the wetting characteristics of liquid Cu on an alumina substrate has been studied in parallel with the study of the joining of alumina through the use of microdesigned multilayer Cu/80Ni . 20Cr/Cu interlayers. While Ni additions do not reduce the contact angle of liquid Cu on an Al2O3 substrate, additions of 80Ni . 20Cr or Cr alone do reduce the contact angle. The contact angle reduction depends upon the Cr content of the sessile drop. The average strength and the standard deviation of PTLP bonded alumina were 259 +/- 25 MPa for 99.5% Al2O3 and 494 +/- 61 MPa for 99.9% Al2O3, respectively. The resulting joints can exhibit a high bend strength at room temperature, strengths approaching those of the unbonded alumina, and a relatively narrow strength distribution. In both cases, failure occurred either entirely within the ceramic or primarily in the ceramic, with limited crack propagation along the alumina/interlayer interface. C1 Kyushu Univ, Fac Engn, Dept Mat Sci & Engn, Higashi Ku, Fukuoka 812, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Nakashima, K (reprint author), Kyushu Univ, Fac Engn, Dept Mat Sci & Engn, Higashi Ku, 6-10-1 Hakozaki, Fukuoka 812, Japan. NR 12 TC 2 Z9 3 U1 0 U2 2 PU PLENUM PUBL CORP PI NEW YORK PA CONSULTANTS BUREAU, 233 SPRING ST, NEW YORK, NY 10013 USA SN 1064-7562 J9 J MATER SYNTH PROCES JI J. Mater. Synth. Process PD JUL PY 1998 VL 6 IS 4 BP 271 EP 277 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 154GN UT WOS:000077881000010 ER PT J AU Joy, DC AF Joy, DC TI The efficiency of X-ray production at low energies SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article DE X-ray ionization cross-section; fluorescent yield; X-ray generation cross-section; X-ray efficiency; Monte Carlo modelling ID ELECTRON-SOLID INTERACTIONS; K-SHELL IONIZATION; CROSS-SECTIONS; IMPACT AB The absolute efficiency of X-ray production has been determined for the It-lines of Al, Si and Cu: for the L-lines of Fe, Co, Cu, Ge and As: and for the M-lines of Hf. Ir, Pt, Au and Pi, using overvoltage ratios in the range 1-10, These emissions, with the exception of the Cu It, have critical excitation energies below 2.6keV and are therefore typical of the lines used for X-ray microanalysis at low beam energies, For It-lines it is found that the experimental results are in good agreement with a Bethe, or a Casnati, cross-section model, For the L- and M-lines a Monte Carlo technique has been used to find an effective X-ray generation cross-section for each of the elements. The functional forms of these cross-sections are found to be in general agreement with proposed theoretical models. C1 Univ Tennessee, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Joy, DC (reprint author), Univ Tennessee, Knoxville, TN 37996 USA. NR 29 TC 29 Z9 29 U1 0 U2 4 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD JUL PY 1998 VL 191 BP 74 EP 82 PN 1 PG 9 WC Microscopy SC Microscopy GA 109CN UT WOS:000075303800009 PM 9723191 ER PT J AU Hacker, BC AF Hacker, BC TI The chemical weapons taboo SO JOURNAL OF MILITARY HISTORY LA English DT Book Review C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Hacker, BC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SOC MILITARY HISTORY PI LEXINGTON PA C/O VIRGINIA MILITARY INST, GEORGE C MARSHALL LIBRARY, LEXINGTON, VA 24450-1600 USA SN 0899-3718 J9 J MILITARY HIST JI J. Mil. Hist. PD JUL PY 1998 VL 62 IS 3 BP 637 EP 638 DI 10.2307/120453 PG 2 WC History SC History GA 102KQ UT WOS:000074923800020 ER PT J AU Kerns, L Weinberg, MC Myers, S Assink, R AF Kerns, L Weinberg, MC Myers, S Assink, R TI Al coordination in sol-gel and conventional calcium aluminate glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 7th International Conference on the Structure of Non-Crystalline Materials (NCM7) CY SEP 15-19, 1997 CL CAGLIARI, ITALY SP Presidenza Giunta Reg, Reg Autonoma Sardegna, Assessorato Affari Gen, Camera Commercio Ind Artigianato & Agr, EMSA, Ente Minerario Sardo, Fdn Banco Sardegna, Univ Cagliari, CNR, Com Chim, INCM, Consorzio Interuniv Nazl Chim Mat, SARAS Raffinerie Sarde, Comune Iglisias, Assoc Univ Sulcis Iglesiente, Ente Sardo Ind Turistiche ID NUCLEAR-MAGNETIC-RESONANCE; AL-27 NMR; SPECTROSCOPY; RAMAN AB We present the results of a study in which we compared one aspect of structure for a conventionally prepared glass and sol-gel material in the calcium aluminate (CA) family of composition 50CaO . 50Al(2)O(3) (wt%). The work was directed towards a comparison of the aluminum coordination in the two materials, which was determined via (27)Al magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy. Also, infra red (IR) spectroscopy was utilized to compare the hydroxyl content and the structural features of the materials. The Al coordination was examined in gels which were subjected to various heat treatments, some of which produced partial or nearly complete crystallization. We observed, as found previously by others, that in the conventionally prepared glass all the Al atoms are tetrahedrally (4-fold) coordinated. On the other hand, in all the sol-gel materials, regardless of heat treatment schedule, a fraction of the Al is found to be in octahedral (G-fold) coordination. We found that. as the hydroxyl content of the gel increases, the ratio of 6-fold to 4-fold Al increased. Hence, the presence of octahedral coordination in the gel is largely, and most likely totally, due to the water content of this material. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Arizona, Dept Mat Sci & Engn, Arizona Mat Lab, Tucson, AZ 85721 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Weinberg, MC (reprint author), Univ Arizona, Dept Mat Sci & Engn, Arizona Mat Lab, Bldg 12,4715 E Ft Lowell Rd, Tucson, AZ 85721 USA. EM mcw@u.arizona.edu NR 20 TC 15 Z9 15 U1 2 U2 10 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 JUL PY 1998 VL 232 BP 86 EP 92 DI 10.1016/S0022-3093(98)00376-7 PG 7 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 113NU UT WOS:000075558800013 ER PT J AU Sales, BC Boatner, LA Ramey, JO AF Sales, BC Boatner, LA Ramey, JO TI Intermediate-range order in simple metal-phosphate glasses: The effect of metal cations on the phosphate-anion distribution SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 7th International Conference on the Structure of Non-Crystalline Materials (NCM7) CY SEP 15-19, 1997 CL CAGLIARI, ITALY SP Presidenza Giunta Reg, Reg Autonoma Sardegna, Assessorato Affari Gen, Camera Commercio Ind Artigianato & Agr, EMSA, Ente Minerario Sardo, Fdn Banco Sardegna, Univ Cagliari, CNR, Com Chim, INCM, Consorzio Interuniv Nazl Chim Mat, SARAS Raffinerie Sarde, Comune Iglisias, Assoc Univ Sulcis Iglesiente, Ente Sardo Ind Turistiche ID STRUCTURAL-PROPERTIES AB The technique of high-performance liquid chromatography (HPLC) has been used to determine the phosphate-anion distribution in a variety of metal phosphate glasses-including glasses made with the trivalent metal cations: Al, In, Ga, and La. The composition of each glass was chosen so that the average phosphate chain length was between 2 and 4 PO(4) tetrahedra. The widths of the resulting phosphate-anion chain-length distributions were determined directly from an analysis of the HPLC chromatograms. Literature values for the free energy of formation of the crystalline metal-orthophosphate compounds with respect to P(2)O(5) and the metal oxide were compared to the width of the phosphate-anion chain-length distributions. We found that the smaller the energy of formation, the wider the distribution of phosphate chains, and the greater the ease of glass formation. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Sales, BC (reprint author), Oak Ridge Natl Lab, Div Solid State, MS-6056,Bldg 3150,POB 2008, Oak Ridge, TN 37831 USA. EM vb4@ornl.gov RI Boatner, Lynn/I-6428-2013 OI Boatner, Lynn/0000-0002-0235-7594 NR 11 TC 16 Z9 16 U1 1 U2 8 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 JUL PY 1998 VL 232 BP 107 EP 112 DI 10.1016/S0022-3093(98)00379-2 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 113NU UT WOS:000075558800016 ER PT J AU Suzuya, K Price, DL Loong, CK Martin, SW AF Suzuya, K Price, DL Loong, CK Martin, SW TI Structure of vitreous P2O5 and alkali phosphate glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 7th International Conference on the Structure of Non-Crystalline Materials (NCM7) CY SEP 15-19, 1997 CL CAGLIARI, ITALY SP Presidenza Giunta Reg, Reg Autonoma Sardegna, Assessorato Affari Gen, Camera Commercio Ind Artigianato & Agr, EMSA, Ente Minerario Sardo, Fdn Banco Sardegna, Univ Cagliari, CNR, Com Chim, INCM, Consorzio Interuniv Nazl Chim Mat, SARAS Raffinerie Sarde, Comune Iglisias, Assoc Univ Sulcis Iglesiente, Ente Sardo Ind Turistiche ID X-RAY-DIFFRACTION; ULTRAPHOSPHATE GLASSES; SHORT-RANGE; NEUTRON AB The structure of vitreous P2O5 (v-P2O5), sodium ultraphosphate glasses, (Na2O)(x)(P2O5)(100-x) (x = 10, 20), and alkali metaphosphate glasses, MePO3 (Me = Li, Na, K, Rb and Cs), have been studied by neutron diffraction. Structural features in the neutron structure factors. S(Q), characteristic of intermediate-range (Q less than or similar to 3 A(-1)) order were identified. The feature of intermediate-range order in V-P2O5 is accounted for by the P4O10 molecule packing model. The addition of the alkali metal modifier, Na, has an effect on the intermediate-range structure due to destruction of the PO4 network structure. Around x similar to 50 a new peak appears at lower Q than the intermediate-range order peak, which is found in the S(Q)'s of all alkali metaphosphate glasses, which may be associated with extended-range order. The length scale of the extended-range order increases with Me+ size. These phenomena can be explained by the affects of oxygen atoms, i.e. PO4 chain-like units, ordering around the Me+. (C) 1998 Elsevier Science B.V. AII rights reserved. C1 Japan Atom Energy Res Inst, Dept Synchrotron Radiat Res, Ako, Hyogo 67812, Japan. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Suzuya, K (reprint author), Japan Atom Energy Res Inst, Dept Synchrotron Radiat Res, Ako, Hyogo 67812, Japan. EM suzuya@spring8.or.jp RI Price, David Long/A-8468-2013 NR 29 TC 47 Z9 47 U1 0 U2 11 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 JUL PY 1998 VL 232 BP 650 EP 657 DI 10.1016/S0022-3093(98)00529-8 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 113NU UT WOS:000075558800099 ER PT J AU Green, PF Sidebottom, DL Brow, RK Hudgens, JJ AF Green, PF Sidebottom, DL Brow, RK Hudgens, JJ TI Mechanical relaxation anomalies in mixed alkali oxides SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID IONIC-TRANSPORT-PROPERTIES; CONDUCTING GLASSES; ATOMIC-STRUCTURE; RESONANCE; PHOSPHATE; MODEL; NMR; DC AB Mechanical relaxation (MR) processes were investigated in single and mixed alkali (MA) metaphosphate glasses using a dynamic mechanical analyzer (DMA) over a range of frequencies, 0.1-50 Hz, and temperatures, 24-250 degrees C. The mechanical loss modulus, M ", of each mixed, sodium and lithium, alkali glass exhibited two characteristic maxima, a large maximum just below T-g, and a well developed, yet considerably diminished in amplitude, maximum at a much lower temperature. The single alkali analogs, on the other hand, exhibited only a single maximum and this maximum appeared in the same location as the lower temperature peak observed in the MA glasses. The location of these maxima are identified with dynamic processes within the glass which occur with average frequencies, nu(mu)(Na, Li), for the high T maximum in the mixed glasses, and nu(mu) (Li) and nu(mu) (Na) for the lithium and sodium glasses, respectively. These frequencies nu(mu)(Na, Li), nu(mu) (Li) and nu(mu) (Na), varied exponentially with 1/T; nu(mu) (Na, Li) had the largest activation energy. In addition nu(mu)(Na, Li) << nu(mu)(Na) < nu(mu)(Li) for T < T-g. Two other important observations were made, the high temperature maximum in M " reached its largest amplitude when the mole fractions of Na2O and Li2O were comparable and nu(mu) (Na, Li) exhibited a maximum in the same composition range. Our observations are discussed in light of a local site-memory relaxation model based on the notion that below T,, cation hopping dynamics are intimately coupled with local glass network relaxations. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Texas, Texas Mat Inst, Dept Chem Engn, Austin, TX 78712 USA. Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87110 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Green, PF (reprint author), Univ Texas, Texas Mat Inst, Dept Chem Engn, ETC 9-104, Austin, TX 78712 USA. EM green@che.utexas.edu NR 32 TC 15 Z9 15 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD JUL PY 1998 VL 231 IS 1-2 BP 89 EP 98 DI 10.1016/S0022-3093(98)00447-5 PG 10 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY347 UT WOS:000074611500009 ER PT J AU Treacy, MMJ Gibson, JM Keblinski, PJ AF Treacy, MMJ Gibson, JM Keblinski, PJ TI Paracrystallites found in evaporated amorphous tetrahedral semiconductors SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID SILICON; CRYSTALLIZATION; RELAXATION; SCATTERING; COHERENCE; FILMS; ORDER; SI; GE AB Variable coherence microscopy shows that as-deposited amorphous germanium and silicon contain medium-range order. The ordering can be explained by a fine-grained paracrystallite material in which intergranular stress has been relaxed by deformation. On annealing, the paracrystallite structure transforms towards the lower-energy continuous random network (CRN). We present data on a variety of vacuum-evaporated samples, and on molecular dynamics simulations of candidate structures. (C) 1998 Elsevier Science B.V. All rights reserved. C1 NEC Res Inst Inc, Princeton, NJ 08540 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Dept Mat Sci, Urbana, IL 61801 USA. Argonne Natl Labs, Argonne, IL 60439 USA. RP Treacy, MMJ (reprint author), NEC Res Inst Inc, 4 Independence Way, Princeton, NJ 08540 USA. EM treacy@research.nj.nec.com; j-gibson@uiuc.edu; pawel_keblinski@qmgate.anl.gov RI Gibson, Murray/E-5855-2013 OI Gibson, Murray/0000-0002-0807-6224 NR 31 TC 101 Z9 101 U1 3 U2 14 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 JUL PY 1998 VL 231 IS 1-2 BP 99 EP 110 DI 10.1016/S0022-3093(98)00371-8 PG 12 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY347 UT WOS:000074611500010 ER PT J AU Sunwoo, AJ Accardo, RN Gourdin, WH AF Sunwoo, AJ Accardo, RN Gourdin, WH TI Effects of heat treatment on grain refinement in cast uranium 0.25 wt% vanadium alloy SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article AB The feasibility of refining the grain size of large castings of uranium-0.25 wt% vanadium alloy has been successfully demonstrated using a helium-mediated 'isothermal' heat treatment in a large commercial vacuum furnace. Using th:is method, the grains of 10-20 kg hemispherical castings were refined from 180 mu m diameter to 35 mu m, a reduction similar to that achieved in both laboratory-scale isothermally transformed material and carefully controlled wrought-processed uranium. The results of compression and tension tests on the cast alloy and the wrought uranium at a strain rate of 10(-3) s(-1) indicate that up to a strain of 30%, the cast and heat-treated uranium-0.25% vanadium alloy exhibits a higher compressive flow stress than that of comparable wrought uranium. In tension, the cast and heat treated alloy continues to exhibit high strengths, but displays a lower ductility. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Sunwoo, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,7000 East Ave, Livermore, CA 94551 USA. NR 18 TC 2 Z9 2 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 JUL PY 1998 VL 256 IS 1 BP 53 EP 64 DI 10.1016/S0022-3115(98)00052-X PG 12 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 107FU UT WOS:000075197200006 ER PT J AU Shen, S DeNardo, GL Jones, TD Wilder, RB O'Donnell, RT DeNardo, SJ AF Shen, S DeNardo, GL Jones, TD Wilder, RB O'Donnell, RT DeNardo, SJ TI A preliminary cell kinetics model of thrombocytopenia after radioimmunotherapy SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE radionuclide therapy; radioimmunotherapy; marrow cell kinetics; radiation dosimetry; thrombocytopenia ID BONE-MARROW; I-131 LYM-1; STEM-CELLS; RADIATION AB Thrombocytopenia is often the dose-limiting toxicity for radionuclide therapy. Prediction of platelet counts after therapy is important for treatment planning. Simple prediction methods based on linear correlation between radiation dose and blood count nadir have been insufficient because they have not considered time, because of the complicated hierarchical structure of the hematopoietic system in which platelets are not directly injured by low dose rate radiation and because of changing radiation dose rates to marrow with time, This study addresses these problems using a cell kinetics model. Methods: The model consists of compartments for progenitor cells, megakaryocytes, platelets and stromal cells. A linear quadratic formula was used for progenitor cell survival. Stromal cells were described by a model based on a maximum likelihood estimate for cellular damage, repair and proliferation. Reported values for murine cellular turnover rates and radiosensitivity of progenitor cells were used in the model calculations. Experimental mice received 4 Gy of external beam radiation for tumor implantation and 12.4-23.3 MBq Cu-67-2-iminothiolane-BAT-Lym-1 (BAT = 6-[p-(bromoacetamido) benzyl]-1,4,8,11-tetra-azacyclotetradecane-N,N',N",N"'-tetraacetic acid) 19-30 days later. Blood counts were measured three times each week. Results: The model predicted the severity of thrombocytopenia, and the time of the nadir corresponded to measured values in mice. For a dose of 14.2 MBq Cu-67-2-iminothiolane-BAT-Lym-1 that induced a platelet nadir of 20% of baseline (Grade II), the model predicted that at least 20 days were needed before a second 14.2-MBq injection if a subsequent nadir of <10% of baseline (Grade IV) was to be avoided. Conclusion: The nadir and duration of thrombocytopenia predicted by the model were similar to those observed in the mice. Predicted information could be useful for planning the dose and timing of fractionated radionuclide therapy. This model provides a stepping stone for future development of a predictive model for patients. C1 Univ Calif Davis, Radiodiag & Therapy Sect, Div Hematol Oncol & Radiat Oncol, Sacramento, CA 95816 USA. Oak Ridge Natl Lab, Chem & Biol Phys Sect, Oak Ridge, TN USA. Vet Adm No Calif Hlth Care Syst, Martinez, CA USA. RP Shen, S (reprint author), Univ Calif Davis, Radiodiag & Therapy Sect, Div Hematol Oncol & Radiat Oncol, 1508 Alhambra Blvd,Room 214, Sacramento, CA 95816 USA. FU NCI NIH HHS [CA47829] NR 27 TC 11 Z9 11 U1 1 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD JUL PY 1998 VL 39 IS 7 BP 1223 EP 1229 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZZ059 UT WOS:000074691600026 PM 9669399 ER PT J AU Gaiser, EE Philippi, TE Taylor, BE AF Gaiser, EE Philippi, TE Taylor, BE TI Distribution of diatoms among intermittent ponds on the Atlantic Coastal Plain: development of a model to predict drought periodicity from surface-sediment assemblages SO JOURNAL OF PALEOLIMNOLOGY LA English DT Article DE diatoms; Carolina bays; paleolimnology; calibration set; non-metric multidimensional scaling; weighted-averaging ID COLUMBIA CANADA LAKES; SOUTH-CAROLINA; RECONSTRUCTION; REGRESSION; HYDROLOGY; PATTERNS; SALINITY; HISTORY; BAYS AB Inferences of past climate from the fossil record in lakes rely on the accurate quantification of a relationship of fossilizing organisms to their environment Whereas the relationship of diatoms to water chemistry parameters has been modeled in many systems, few studies adequately address the relationship of diatoms to physical properties, such as water depth or hydrology, that may be more directly tied to climate. We examined the composition of modern diatoms in surface sediments of 75 isolated ponds (mostly Carolina bays) of the Atlantic Coastal Plain to: (1) assess the influence of physical and chemical variables on the distribution of diatoms among ponds of the region, and (2) develop a model that predicts hydroperiod (a measure of pond permanence) from diatom assemblages. We constructed two hydroperiod calibration models: the first infers hydroperiod from the weighted-average optima and tolerances of taxa along the hydroperiod gradient, the second bases inferences on the hydroperiod estimates of compositionally similar samples. Both approaches incorporate a-priori and post-hoc tests of assumptions often inherent in the construction of transfer functions. Diatom assemblage composition had strong, approximately linear relationships to hydroperiod, water depth, and calcium concentration in non-metric multidimensional ordination space; effects of other variables, including pH, were non-linear or ambiguous. Overall, the assemblages reflected the dilute, acidic chemical characteristics of bays. The assemblages contained differing abundances of euterrestrial, benthic and planktonic taxa, depending on a pond's susceptibility to drying. A weighted-averaging regression model based on taxon-specific hydroperiod optima generated adequate, unbiased hydroperiod inferences from diatom species composition (r(2) = 0.81). This model may be used to infer past drought episodes from fossil diatom assemblages at appropriate sites on the Atlantic Coastal Plain. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Gaiser, EE (reprint author), Florida Int Univ, SE Environm Res Program, Miami, FL 33199 USA. NR 77 TC 30 Z9 31 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0921-2728 J9 J PALEOLIMNOL JI J. Paleolimn. PD JUL PY 1998 VL 20 IS 1 BP 71 EP 90 DI 10.1023/A:1007969500673 PG 20 WC Environmental Sciences; Geosciences, Multidisciplinary; Limnology SC Environmental Sciences & Ecology; Geology; Marine & Freshwater Biology GA 103BA UT WOS:000074959700006 ER PT J AU Santarius, JF Logan, BG AF Santarius, JF Logan, BG TI Generic magnetic fusion rocket model SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID SPACE PROPULSION; POWER; FUEL; HE-3 AB A generic magnetic fusion rocket model is developed and used to explore the limits of magnetic fusion propulsion systems. Two fusion fuels are examined, D-T and D-He-3, and the D-He-3 fuel cycle is predicted to give a higher specific power for optimized parameters. Other findings are that magnetic fusion should ultimately be able to deliver specific powers of similar to 10 kW/kg and that specific powers of 1-5 kW/kg should be achievable with only modest extrapolations of present technology. C1 Univ Wisconsin, Fus Technol Inst, Madison, WI 53706 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Santarius, JF (reprint author), Univ Wisconsin, Fus Technol Inst, 1500 Engn Dr, Madison, WI 53706 USA. NR 34 TC 9 Z9 9 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD JUL-AUG PY 1998 VL 14 IS 4 BP 519 EP 524 DI 10.2514/2.5308 PG 6 WC Engineering, Aerospace SC Engineering GA 100HK UT WOS:000074810600014 ER PT J AU Thode, LE Cline, MC Howe, SD AF Thode, LE Cline, MC Howe, SD TI Vortex formation and stability in a scaled gas-core nuclear rocket configuration SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA/ASME/SAE/ASEE 33rd Joint Propulsion Conference CY JUL 06-09, 1997 CL SEATTLE, WASHINGTON SP Amer Inst Aeronaut & Astronaut, ASME, SAE, ASEE AB Realistic interplanetary space exploration depends critically upon the development of a high-specific-impulse propulsion system. Previous studies indicate that the specific impulse of an open-cycle gas-core nuclear rocket (OCGCNR) might approach 3000 s, Although the OCGCNR is deceptively simple in concept, it will be difficult to develop in practice because the core is a uranium plasma that must be nearly totally confined. Before constructing a more comprehensive model for this engine, there is a requirement to understand the limits of present full-scale simulation models and recent scaled experiments. In this scoping study we have used a two-dimensional, axisymmetric, finite difference code to investigate the formation and stability of a recirculation region observed in a scaled experiment, It has been proposed that such a recirculation region, or vortex, might provide improved confinement of the uranium fuel. Our simulation results indicate that a more comprehensive model must treat the rocket nozzle in a self-consistent fashion to properly calculate the confinement of the uranium plasma. Under conditions that lead to vortex formation, the position of the vortex depends upon the inlet geometry and injection velocity, the nozzle position and subsonic convergence angle, the base-bleed injection rate, and turbulence. With a large base-bleed injection rate, a vortex forms but is then swept away through the nozzle, a result that resolves an inconsistency between a full-scale engine simulation model and recent scaled experiments. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Div, Los Alamos, NM 87544 USA. RP Thode, LE (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Div, POB 1663, Los Alamos, NM 87544 USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD JUL-AUG PY 1998 VL 14 IS 4 BP 530 EP 536 DI 10.2514/2.5310 PG 7 WC Engineering, Aerospace SC Engineering GA 100HK UT WOS:000074810600016 ER PT J AU Nash, TJ Sanford, TWL Deeney, C Spielman, RB Seaman, J McGurn, J Jobe, DO Mock, RC Gilliland, TL Apruzese, JP Whitney, KG AF Nash, TJ Sanford, TWL Deeney, C Spielman, RB Seaman, J McGurn, J Jobe, DO Mock, RC Gilliland, TL Apruzese, JP Whitney, KG TI High temperature, dense cores in an aluminum wire array z-pinches observed by spatially-resolved spectroscopy SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID X-RAY-EMISSION; LABORATORY PLASMAS; IMPLOSIONS AB We have observed a hot, dense plasma core from an aluminum wire-array z pinch on the accelerator Saturn. A spatially resolved and temporally integrated crystal spectrometer shows aluminum K-shell free-bound continuum emission to be localized to less than 1 mm in diameter and to have a slope indicating a 1.4 keV electron temperature. A keV-filtered temporally resolved pinhole camera corroborates the I mm diameter plasma and a filtered photoconducting detector shows the temporal FWHM of the 4 TW of Al K-shell emission to be 5 ns. Roughly half of the Al K-shell emissions are due to free-bound recombinations. The intensity of the free-bound continuum indicates a core electron density of 3e21/cc. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. USN, Res Lab, Washington, DC 20375 USA. RP Nash, TJ (reprint author), Sandia Natl Labs, MS 1194, Albuquerque, NM 87185 USA. NR 18 TC 4 Z9 4 U1 0 U2 1 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 JUL PY 1998 VL 60 IS 1 BP 97 EP 102 PG 6 WC Optics; Spectroscopy SC Optics; Spectroscopy GA ZM063 UT WOS:000073501000010 ER PT J AU Morton, JS Verwolf, MC Woolf, S AF Morton, JS Verwolf, MC Woolf, S TI The preparation and application of performance evaluation materials 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 Radiological and Environmental Sciences Laboratory administers three separate programs that include the use of prepared evaluation material to assess the performance of the participant laboratories. The performance materials include a simple liquid matrix to soil containing organic compounds to synthetic excreta containing known concentrations of radionuclides. The paper discusses the quality control associated with the preparation of these materials. The concept of synthetic-standard enhancement of a natural matrix is briefly discussed to demonstrate homogeneity. The use of verified standards and the assurance of homogeneity by preparation method and characterization are shown to be the necessary components of useful and accurate performance evaluation materials. Because each of the performance programs is tailored to the specific needs of the participants, a discussion of the acceptance criteria is also included. C1 US DOE, Radiol & Environm Sci Lab, Idaho Falls, ID 83402 USA. RP Morton, JS (reprint author), US DOE, Radiol & Environm Sci Lab, Idaho Falls, ID 83402 USA. NR 7 TC 0 Z9 0 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 JUL PY 1998 VL 233 IS 1-2 BP 37 EP 41 DI 10.1007/BF02389644 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300007 ER PT J AU Wong, AS Marshall, RS AF Wong, AS Marshall, RS TI Radiometric measurements on non-destructive assay standards fabrication for WIPP Performance Demonstration Program 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 Inorganic Elemental Analysis Group of LANL has prepared several different sets of working reference materials (WRMs). These WRMs are prepared by blending quantities of nuclear materials (plutonium, americium, and enriched uranium) with diatomaceous earth. The blends are encapsulated in stainless steel cylinders. These WRMs are being measured as blind controls in neutron and gamma based non-destructive assay (NDA) instruments. Radiometric measurements on the blending homogeneity and verification on a set of sixty-three plutonium based WRMs are discussed in this paper. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Wong, AS (reprint author), Univ Calif Los Alamos Natl Lab, MS G740, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 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 JUL PY 1998 VL 233 IS 1-2 BP 43 EP 48 DI 10.1007/BF02389645 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300008 ER PT J AU Heath, RL AF Heath, RL TI Development of new expanded editions of the Gamma-ray Spectrum Catalogues in electronic format 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 A program has been developed at the INEL to produce new enhanced editions of the original Gamma-ray Spectrum Catalogues for presentation in electronic format. This program has produced the first version of the Catalogues in CD-ROM format and will offer them on the Internet through the Gamma-ray Spectrometry Center Web Site at INEEL. The original content of the Catalogues has been expanded to include integrated decay scheme drawings, tables of related decay data, and updated material on the techniques of gamma-ray spectrometry. All of the original spectral plots, gamma-ray energy and intensity data, and text were converted to digital format, related decay data from the Evaluated Nuclear Structure Data File (ENSDF) and decay scheme graphics were then added, and all data converted to the Adobe Acrobat (PDF) format. Follow-on versions of the catalogues are being expanded to include prompt neutron capture and n-n' spectra and spectra representing the response of large-volume Ge detectors. Large-volume Ge detector spectra will be calculated using Monte Carlo and parametric fitting techniques presently under development. Examples of content and details of the advanced technology applied to produce these new volumes will be presented. Services and content of the Gamma-ray Spectrometry Center Web Site will also be described. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Heath, RL (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 7 TC 2 Z9 3 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 JUL PY 1998 VL 233 IS 1-2 BP 81 EP 89 PG 9 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300014 ER PT J AU Hensley, WK Lepel, EA AF Hensley, WK Lepel, EA TI SYNTH: A new tool for estimating interferences in instrumental neutron activation 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 SYNTH, a Windows(TM) based software package developed for generating synthetic gamma-ray spectra, has been updated and extended to include the ability to generate gamma-ray spectra resulting from neutron activation. Along with a new gamma-ray library (based on the NNDC PCNuDat compilation), and the best available neutron cross-sections, it is now possible to simply, and quickly predict the interference effects of different bulk and trace element compositions by generating a synthetic gamma-ray spectrum that will be representative of a specific set of input parameters. The parameters include, but are not limited to: elemental composition (bulk, and trace) of the sample; irradiation, decay, and count times; thermal, and resonance neutron flux; sample to detector distance; detector specifications; and electronics configuration. Using existing data reduction codes, it is then possible to generate Minimum Detectable Activities (MDA's) for other trace elements that you may wish to detect in this type of matrix. C1 Pacific NW Lab, Nucl Chem Sect, Richland, WA 99352 USA. RP Hensley, WK (reprint author), Pacific NW Lab, Nucl Chem Sect, POB 999, Richland, WA 99352 USA. NR 4 TC 3 Z9 3 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 JUL PY 1998 VL 233 IS 1-2 BP 91 EP 94 DI 10.1007/BF02389652 PG 4 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300015 ER PT J AU Gardner, RP Guo, P Sood, A Mayo, CW Gehrke, RJ Dobbs, CL AF Gardner, RP Guo, P Sood, A Mayo, CW Gehrke, RJ Dobbs, CL TI Monte Carlo aided treatments of the nonlinear inverse PGNAA measurement problem for various continuous on-line applications 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 A review of our work on the application of the PGNAA method as applied to five industrial applications is given. Some introductory material is first given on the importance and use of Monte Carlo simulation in this area, some comments on the place of PGNAA in elemental analysis, and a brief description of the Monte Carlo - Library Least-Squares (MCLLS) approach to the nonlinear inverse PGNAA analysis problem. Then the applications of PGNAA are discussed for: (1) on-line bulk coal analysis, (2) nuclear oil well logging, (3) vitrified waste, (4) the analysis of sodium and aluminum in "green liquor" in the presence of chlorine, and (5) the conveyor belt sorting of aluminum alloy samples. It is concluded that PGNAA is a rapidly emerging important new technology and measurement approach. C1 N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Raleigh, NC 27695 USA. EG&G Idaho Inc, Idaho Natl Engn Lab, Idaho Falls, ID USA. ALCOA, Ctr Tech, Alcoa Center, PA USA. RP Gardner, RP (reprint author), N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Raleigh, NC 27695 USA. NR 6 TC 3 Z9 3 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 JUL PY 1998 VL 233 IS 1-2 BP 105 EP 107 DI 10.1007/BF02389655 PG 3 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300018 ER PT J AU Killian, EW East, LV AF Killian, EW East, LV TI PCGAP: Application to analyze gamma-ray pulse-height spectra on a personal computer under Windows NT (R) 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 PCGAP is a software code, which was written to provide gamma-ray pulse height spectrum analysis on a personal computer platform. The code was specifically developed for Windows NT for either an Intel(R) or DEC Alpha(R) based processor. PCGAP includes programs which can be used to control data collection using a Canberra INSPECTOR(R) multichannel pulse-height analyzer. With suitable spectrum conversion routines PCGAP can be used to analyze data from almost any multi-channel analyzer. Besides the normal functions associated with a robust spectrum analysis package, PCGAP can be used for radionuclide analysis for actinides via LX and gamma-ray spectrometry. It can be used to control and analyze data from an INEEL developed pulse injection system for individual spectrum validation. The package includes programs for the manual analysis of spectra using displays which permit the spectroscopist to interactively define the spectral continuum and peak fitting limits, and display the resulting function fitting forms. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. RP Killian, EW (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. NR 4 TC 13 Z9 13 U1 0 U2 2 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 JUL PY 1998 VL 233 IS 1-2 BP 109 EP 114 DI 10.1007/BF02389656 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300019 ER PT J AU Aalseth, CE Avignone, FT Brodzinski, RL Miley, HS Reeves, JH AF Aalseth, CE Avignone, FT Brodzinski, RL Miley, HS Reeves, JH TI Using pulse shape discrimination to sort individual energy deposition events in a germanium crystal 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 DETECTORS AB A fast digital oscilloscope based pulse shape discrimination (PSD) system has been tested with intrinsic germanium detectors large enough to allow ionizing events which generate localized electron-hole pairs at a single site to be segregated from those depositing energy at several different sites in the crystal. Drift velocities of the electrons and holes result in pulses several hundred nanoseconds long. Since the electric field varies by almost a factor of 10 between the outer and inner surfaces, collection of electrons and holes can frequently be distinguished, and pulses due to multi-site events can be distinguished from single site events. C1 Univ S Carolina, Columbia, SC 29208 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Aalseth, CE (reprint author), Univ S Carolina, Columbia, SC 29208 USA. NR 7 TC 3 Z9 3 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 JUL PY 1998 VL 233 IS 1-2 BP 119 EP 123 DI 10.1007/BF02389658 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300021 ER PT J AU Giles, JR Dooley, KJ AF Giles, JR Dooley, KJ TI High resolution gamma-spectroscopy well logging system 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 A Gamma Spectroscopy Logging System (GSLS) has been developed to study sub-surface radionuclide contamination. The absolute counting efficiencies of the GSLS detectors were determined using cylindrical reference sources. More complex borehole geometries were modeled using commercially available shielding software and correction factors were developed based on relative gamma-ray fluence rates. Examination of varying porosity and moisture content showed that as porosity increases, and as the formation saturation ratio decreases, relative gamma-ray fluence rates increase linearly for all energies. Correction factors for iron and water cylindrical shields were found to agree well with correction factors determined during previous studies allowing for the development of correction factors for type-304 stainless steel and low-carbon steel casings. Regression analyses of correction factor data produced equations for determining correction factors applicable to spectral gamma-ray well logs acquired under non-standard borehole conditions. C1 Lockheed Martin Idaho Technol Co, Idaho Falls, ID USA. RP Giles, JR (reprint author), Lockheed Martin Idaho Technol Co, Idaho Falls, ID USA. NR 15 TC 1 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 JUL PY 1998 VL 233 IS 1-2 BP 125 EP 130 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300022 ER PT J AU Brodzinski, RL Penswick, LB AF Brodzinski, RL Penswick, LB TI A miniature stirling cycle cooler for radiation detectors 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 Germanium spectrometers must be operated at liquid nitrogen temperatures. Other detectors operate better when cooled. Many applications, because of hostile environments, inaccessibility, remote location, long duration, etc., are compromised, or totally precluded, by the requirement for liquid nitrogen. A Stirling cycle refrigerator based on a linear motor design, which is acoustically and vibrationally quiet, does not require secondary cooling, and operates unattended for years, is under development. System design and specifications are presented. Applications to cooled laser monitoring equipment, SQUID-based detection systems, environmental cleanup and monitoring, medical diagnostics, non-destructive resting systems, communication equipment, computer electronics, and imaging systems are discussed. C1 Pacific NW Lab, Richland, WA 99352 USA. Stirling Technol Co, Kennewick, WA 99336 USA. RP Brodzinski, RL (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 0 TC 1 Z9 1 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 JUL PY 1998 VL 233 IS 1-2 BP 131 EP 135 DI 10.1007/BF02389660 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300023 ER PT J AU Koskelo, MJ Woodward, GH Gehrke, RJ Hoggan, JM McLaughlin, GD AF Koskelo, MJ Woodward, GH Gehrke, RJ Hoggan, JM McLaughlin, GD TI Performance testing of two dual-energy pulsers 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 Idaho National Engineering Laboratory (INEL) has been developing a dual energy pulser for dead time and random summing corrections, and for the assessment of the quality of the data for many years. This effort now includes several revisions of the original concept. Recently, Canberra has developed a version of this dual energy pulser as part of a technology transfer from INEL to Canberra Industries. This new design includes many of the same characteristics as the original INEL design. In this paper, we will present the results of a series of tests performed at INEL with both the latest INEL pulser design and the Canberra design. These test results include measurement results of pulser peak width, energy equivalence and dead rime and random summing correction capability as a function of count rate and temperature. It is demonstrated that both designs perform comparably with count rate and temperature when operated over a limited temperature range. In applications where extreme temperature variations are likely during the measurements, the INEL design is the better choice. C1 Canberra Ind, Meriden, CT 06450 USA. Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Koskelo, MJ (reprint author), Canberra Ind, Meriden, CT 06450 USA. NR 9 TC 3 Z9 3 U1 1 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 JUL PY 1998 VL 233 IS 1-2 BP 137 EP 141 DI 10.1007/BF02389661 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300024 ER PT J AU Bowers, DL Rhodes, EA Dickerman, CE AF Bowers, DL Rhodes, EA Dickerman, CE TI A switchable radioactive neutron source: Proof-of-principle 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 feasibility of a practical switchable radioactive neutron source (SRNS) that can be switched on and off like an accelerator and is field portable has been demonstrated. A stable, thin film of Pu-238 oxide deposited on a stainless steel planchet was the alpha source and beryllium was the light element target that produced neutrons. This device requires minimal, if any, shielding when not in use. Design specifications and performance of this proof-in-principle instrument are discussed. C1 Argonne Natl Lab, Div Chem Technol, Analyt Chem Lab, Argonne, IL 60439 USA. Argonne Natl Lab, Reactor Engn Div, Argonne, IL 60439 USA. RP Bowers, DL (reprint author), Argonne Natl Lab, Div Chem Technol, Analyt Chem Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 4 TC 4 Z9 4 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 JUL PY 1998 VL 233 IS 1-2 BP 161 EP 165 DI 10.1007/BF02389665 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300028 ER PT J AU Lepel, EA Brodzinski, RL Kohli, R Reeves, JH AF Lepel, EA Brodzinski, RL Kohli, R Reeves, JH TI A flexible, self-contained germanium spectrometer for the in-situ measurement of gamma-ray emitting radionuclides in and around piping 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 In order to certify that process and drain lines which had been used for transporting radioactive materials, and their surrounding environments, are now free of residual contamination, it is both desirable and cost effective to make in situ measurements during the decontamination and decommissioning process. A 4.83-cm diameter modular probe consisting of a liquid nitrogen reservoir, a preamplifier, and a high-resolution germanium gamma-ray spectrometer with flexible connections between the modules has been developed for the measurement of gamma rays in and around piping. The assembly is sufficiently flexible to navigate through a "3-inch diameter p-trap." The probe design and specifications are discussed. Results from an application are presented. C1 Pacific NW Lab, Richland, WA 99352 USA. Battelle Mem Inst, Columbus Labs, Columbus, OH 43201 USA. RP Lepel, EA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 4 TC 0 Z9 0 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 JUL PY 1998 VL 233 IS 1-2 BP 173 EP 176 PG 4 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300030 ER PT J AU Lund, JC Hilton, NR McKisson, JE Van Scyoc, JM Brunett, BA Hermon, H James, RB AF Lund, JC Hilton, NR McKisson, JE Van Scyoc, JM Brunett, BA Hermon, H James, RB TI Gamma-ray imaging and spectroscopy system using room-temperature semiconductor detector elements 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 We report on the design, construction, and testing of a gamma-ray imaging system with spectroscopic capabilities. The imaging system consists of an orthogonal strip detector made from either HgI2 or CdZnTe crystals. The detectors utilize an 8x8 orthogonal strip configuration with 64 effective pixels. Both HgI2 or CdZnTe detectors are 1 cm(2) devices with a strip pitch of approximately 1.2 mm (producing pixels of 1.2 mm x x 1.2 mm). The readout electronics consist of parallel channels of preamplifier, shaping amplifier, discriminators, and peak sensing ADC. The preamplifiers are configured in hybrid technology, and the rest of the electronics are implemented in NIM and CAMAC with control via a Power Macintosh computer. The software used to readout the instrument is capable of performing intensity measurements as well as spectroscopy on all 64 pixels of the device. We report on the performance of the system imaging gamma-rays in the 20-500 keV energy range and using a pin-hole collimator to form the image. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Univ Arizona, Tucson, AZ 85724 USA. RTI Inc, Alachua, FL 32615 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RP Lund, JC (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. EM jlund@sandia.gov NR 9 TC 0 Z9 0 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 JUL PY 1998 VL 233 IS 1-2 BP 177 EP 183 DI 10.1007/BF02389668 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300031 ER PT J AU McDonald, RJ Smith, AR Hurley, DL Norman, EB AF McDonald, RJ Smith, AR Hurley, DL Norman, EB TI Low-level measurement of alpha-particle emitting nuclei in ceramics and lead 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 Nearly all natural materials contain trace quantities of uranium (U) and thorium (Th) and their daughter nuclides, many of which emit alpha-particles in their decay. Lead, at the end of the U-decay chain, typically contains some radioactive Pb-210 which is chemically inseparable from the other Pb isotopes, alpha-particle emission from these decays can affect sensitive electronic components, such as memory chips or processors. Measurement of alpha-particle emitters can be accomplished by direct detection of the alpha-particles (which typically provides no positive identification of the emitting isotope because of energy loss in the sample) or by low-background gamma-ray spectroscopy (which does provide positive identification via characteristic gamma-rays.) The latter is by far the best method for screening kg-sized samples of materials like ceramics, aluminum, iron, or copper. The difference between alpha counting and gamma-ray spectroscopy is less for measuring Pb-210 in Pb since the 46.5 keV characteristic gamma-rays directly following the Pb-210 decay are strongly absorbed and both methods are limited to thin layers. This paper discusses these two cases and concludes that a large n-type germanium gamma-ray spectrometer is probably the best overall system for both measurements. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP McDonald, RJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd,MS 72-150, Berkeley, CA 94720 USA. NR 3 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 JUL PY 1998 VL 233 IS 1-2 BP 185 EP 189 DI 10.1007/BF02389669 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300032 ER PT J AU McDonald, RJ Smith, AR Hurley, DL Norman, EB Schoonover, MR AF McDonald, RJ Smith, AR Hurley, DL Norman, EB Schoonover, MR TI Rapid detailed characterization of concrete shielding blocks utilizing internal natural radionuclides for calibration 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 Following many years of productive research, the 184-inch Cyclotron, the SuperHILAC, and the BEVALAC accelerators at the Berkeley Laboratory were closed, leaving thousands of concrete shielding blocks available for reuse, recycling, or disposal. The process history of these blocks precludes free release pending radiological characterization. This paper describes a procedure whereby a high efficiency shielded germanium spectrometer is used to rapidly characterize natural and man-made activity within the blocks. The spectrometer is moved up to the block and 5 minutes of data are collected at the point on the block that registers highest on a micro-R meter. Sensitivity is better than 1 pCi/g (0.037 Bq/g) for Co-60 and Eu-152, the prominent man-made activities observed. One-time calibration of the detector system is obtained from a sample of concrete, drilled with a hammer drill, counted in our low-background facility, and compared to crushed rock with known U, Th, and K activity. A simple relationship exists between the counts/minute observed in a characteristic gamma-ray peak and the activity in the block. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Hlth & Safety Div, Berkeley, CA 94720 USA. RP McDonald, RJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 2 TC 3 Z9 3 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 JUL PY 1998 VL 233 IS 1-2 BP 191 EP 194 DI 10.1007/BF02389670 PG 4 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300033 ER PT J AU Brodzinski, RL Hensley, WK Lepel, EA Smith, MR AF Brodzinski, RL Hensley, WK Lepel, EA Smith, MR TI Detecting Cs-137 breakthrough in an ion exchange process 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 High-level radioactive wastes can be transformed to low-level wastes by removing Cs-137 through selective ion exchange processes. Since the short-lived daughter, Ba-137m produces the 662-keV gamma-ray normally attributed to Cs-137, equilibrium may be broken, and observation of the 662-keV gamma-ray cannot be used to detect cesium breakthrough. Two detectors viewing the output line, but separated sufficiently to measure the Ba-137m decay between them, are used to detect Cs-137 breakthrough based on deviation from the normal Ba-137m decay. Detectors evaluated for the process, separation time, counting time, fractional breakthrough detectable, and accuracy and confidence of the measurements are discussed. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Brodzinski, RL (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 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 JUL PY 1998 VL 233 IS 1-2 BP 207 EP 210 DI 10.1007/BF02389673 PG 4 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300036 ER PT J AU Lepel, EA Geelhood, BD Hensley, WK Quam, WM AF Lepel, EA Geelhood, BD Hensley, WK Quam, WM TI A field-deployable, aircraft-mounted sensor for the environmental survey of radionuclides 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 Environmental Radionuclide Sensor System (ERSS)(3) is an extremely sensitive sensor, which has been cooperatively developed by Pacific Northwest National Laboratory (PNNL) and Special Technologies Laboratory (STL) for environmental surveys of radionuclides. The ERSS sensors fit in an airborne pod and include twenty High-Purity Germanium (HPGe) detectors for the high-resolution measurement of gamma-ray emitting radionuclides, twenty-four He-3 detectors for possible neutron measurements, and two video cameras for visual correlation. These aerial HPGe sensors provide much better gamma-ray energy resolution than can be obtained with NaI(TI) detectors. The associated electronics fit into three racks. The system can be powered by the 28 V DC electrical supply of typical aircraft or 120 V AC. The data acquisition hardware is controlled by customized software and a real-time display is provided. Each gamma-ray event is time stamped and stored for later analysis. This paper will present the physical design, discuss the software used to control the system, and provide some examples of its use. C1 Pacific NW Lab, Richland, WA 99352 USA. Special Technol Lab, Santa Barbara, CA 93111 USA. RP Lepel, EA (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 1 TC 5 Z9 6 U1 1 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 JUL PY 1998 VL 233 IS 1-2 BP 211 EP 215 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300037 ER PT J AU Gehrke, RJ Killian, EW East, LV Hoggan, JM Goodwin, SG McLaughlin, GD AF Gehrke, RJ Killian, EW East, LV Hoggan, JM Goodwin, SG McLaughlin, GD TI A portable, photon analysis spectrometer for the assay of X- and gamma-ray emitting radionuclides 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 A portable, battery-powered, multichannel analyzer (MCA) for use with Ge spectrometers has been developed for in-field use for the assay of x- and gamma-ray emitting radionuclides. The spectrometer is capable of operating to rates greater than 150,000 counts per second. The analyzer is a Canberra InSpector MCA, that is equipped with the INEEL ultra-stable dual-energy pulser, and pulse injection with subsequent removal (PISR) circuitry. PCGAP, a set of MCA control and spectral analysis programs, was developed for use on a PC with a Windows NT Operating System. It includes an interactive peak analysis program as well as automatic spectral analysis programs for the X- and gamma-ray regions, and a number of utility programs. The pulser peaks are calibrated with radioactive sources in terms of energy (i.e., their energy equivalents are measured) using the PCGAP spectral analysis package so that energy shifts, including those due to changes in temperature or count rate, do not cause a loss of energy calibration. The number of injected low- and high-energy-equivalent pulses is known so the stored pulser pulses can be used for a dead-time and random summing correction. The pulser peaks are also used to monitor any deterioration in spectral quality caused by noise, ground loops, etc. The results of performance tests to demonstrate the capabilities of this pulser-equipped InSpector are reported. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Gehrke, RJ (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 11 TC 2 Z9 2 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 JUL PY 1998 VL 233 IS 1-2 BP 225 EP 231 DI 10.1007/BF02389676 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300039 ER PT J AU Prettyman, TH Cooper, CS Luke, PN Russo, PA Amman, M Mercer, DJ AF Prettyman, TH Cooper, CS Luke, PN Russo, PA Amman, M Mercer, DJ TI Physics-based generation of gamma-ray response functions for CdZnTe detectors 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 RADIATION DETECTORS; CD1-XZNXTE AB A physics-based approach to gamma-ray response-function generation is presented in which the response of CdZnTe detectors is modeled from first principles. Numerical modeling is used to generate response functions needed for spectrum analysis for general detector configurations (e.g., electrode design, detector materials and geometry, and operating conditions). With numerical modeling, requirements for calibration and characterization are significantly reduced. Elements of the physics-based model, including gamma-ray transport, charge carrier drift and diffusion, and circuit response, are presented. Calculated and experimental gamma-ray spectra are compared for a coplanar-grid CdZnTe detector. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA USA. RP Prettyman, TH (reprint author), Univ Calif Los Alamos Natl Lab, NIS-5 MS E540, Los Alamos, NM 87545 USA. OI Prettyman, Thomas/0000-0003-0072-2831 NR 12 TC 10 Z9 10 U1 0 U2 5 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 JUL PY 1998 VL 233 IS 1-2 BP 257 EP 264 DI 10.1007/BF02389681 PG 8 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300044 ER PT J AU Ebara, SB Enghauser, MW AF Ebara, SB Enghauser, MW TI Quantitative portable gamma-spectroscopy sample analysis for non-standard sample geometries 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 Utilizing a portable spectroscopy system, a quantitative method for analysis of samples containing a mixture of fission and activation products in nonstandard geometries was developed. This method was not developed to replace other methods such as Monte Carlo or Discrete Ordinates but rather to offer an alternative rapid solution. The method can be used with various sample and shielding configurations where analysis on a laboratory based gamma-spectroscopy system is impractical. The portable gamma-spectroscopy method involves calibration of the detector and modeling of the sample and shielding to identify and quantify the radionuclides present in the sample. The method utilizes the intrinsic efficiency of the detector and the unattenuated gamma fluence rate at the detector surface per unit activity from the sample to calculate the nuclide activity and Minimum Detectable Activity (MDA). For a complex geometry, a computer code written for shielding applications (MICROSHIELD) is utilized to determine the unattenuated gamma fluence rate per unit activity at the detector surface. Lastly, the method is only applicable to nuclides which emit gamma-rays and cannot be used for pure beta or alpha emitters. In addition, if sample self absorption and shielding is significant, the attenuation will result in high MDA's for nuclides which solely emit low energy gamma-rays. The following presents the analysis technique and presents verification results using actual experimental data, rather than comparisons to other approximations such as Monte Carlo techniques, to demonstrate the accuracy of the method given a known geometry and source term. C1 Sandia Natl Labs, Personal Monitoring & Lab Serv, Radiat Protect Sample Diagnost, Albuquerque, NM 87185 USA. Sci Applicat Int Corp, Las Vegas, NV 89134 USA. RP Ebara, SB (reprint author), Sandia Natl Labs, Personal Monitoring & Lab Serv, Radiat Protect Sample Diagnost, POB 5800,MS 0651, Albuquerque, NM 87185 USA. NR 9 TC 0 Z9 0 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 JUL PY 1998 VL 233 IS 1-2 BP 273 EP 279 DI 10.1007/BF02389683 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 106BR UT WOS:000075110300046 ER PT J AU Dimonte, G Nelson, D Weaver, S Schneider, M Flower-Maudlin, E Gore, R Baumgardner, JR Sahota, MS AF Dimonte, G Nelson, D Weaver, S Schneider, M Flower-Maudlin, E Gore, R Baumgardner, JR Sahota, MS TI Comparative study of viscoelastic properties using virgin yogurt SO JOURNAL OF RHEOLOGY LA English DT Article ID YIELD STRESS; FLOW PROPERTIES; BEHAVIOR; FOODS AB (W)e describe six different tests used to obtain a consistent set of viscoelastic properties for yogurt. Prior to yield, the shear modulus mu and viscosity eta are measured nondestructively using the speed and damping of elastic waves. Although new to foodstuff's, this technique has been applied to diverse materials from metals to the earth's crust. The resultant shear modulus agrees with mu similar to E/3 for incompressible materials, where the Young's modulus E is obtained from a stress-strain curve in compression. The tensile yield stress tau(o) is measured in compression and tension, with good agreement. The conventional vane and cone/plate rheometers measured a shear stress yield tau(os) similar to tau(o)/root 3 as expected theoretically, but the inferred "apparent" viscosity from the cone/plate rheometer is much larger than the wave measurement due to the finite yield (tau(os) not equal 0). Finally, we inverted an open container of yogurt for 10(6) s much greater than eta/mu and observed no motion. This demonstrates unequivocally that yogurt possesses a finite yield stress rather than a large viscosity. We present a constitutive model with a pre-yield viscosity to describe the damping of the elastic waves and use a simulation code to describe yielding in complex geometry. (C) 1998 The Society of Rheology. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Dimonte, G (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 40 TC 12 Z9 13 U1 2 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0148-6055 J9 J RHEOL JI J. Rheol. PD JUL-AUG PY 1998 VL 42 IS 4 BP 727 EP 742 DI 10.1122/1.550915 PG 16 WC Mechanics SC Mechanics GA ZY213 UT WOS:000074597600002 ER PT J AU Woodward, PM Vogt, T AF Woodward, PM Vogt, T TI Electronic band structure calculations of the MNX (M = Zr, Ti; X = Cl, Br, I) system and its superconducting member, Li-doped beta-ZrNCl SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE extended Huckel calculations; electronic band structure; nitride halides; superconductivity AB Electronic band structure calculations have been performed for beta-ZrNCl, beta-ZrNBr, alpha-ZrNBr, alpha-ZrNl, and alpha-TiNX (X = Cl, Br, I) using the extended Huckel method. These calculations reveal that n-doped beta-ZrNCl has a single narrow band at the Fermi level which is stabilized by overlap of 4dz(2) orbitals on zirconium with respect to the remainder of the conduction band states, This band shows only a small degree of dispersion and can essentially be described as a localized Zr-Zr bond when the carrier concentrations are low. The calculated band structure is consistent with the experimental observations of activated carrier transport, and an indirect optical band gap in beta-ZrNCl and beta-ZrNBr, A simple picture is presented which describes a mechanism for strong electron-phonon coupling in the beta-ZrNX structure, suggesting that beta-LixZrNCl is a classical BCS superconductor. This localized 4dz(2) band at the Fermi level is absent in the electronic band structures of alpha-ZrNX and alpha-TiNX compounds. The dispersion relations for these compounds show a direct optical band gap, as observed experimentally. The absence of significant metal-metal bonding in alpha-MNX compounds implies that n-doping will be more difficult to achieve in compounds adopting this structure. The relative stability of alpha- and beta-polymorphs is also discussed. (C) 1998 Academic Press. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Woodward, PM (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Vogt, Thomas /A-1562-2011 OI Vogt, Thomas /0000-0002-4731-2787 NR 22 TC 21 Z9 21 U1 0 U2 7 PU ACADEMIC PRESS INC ELSEVIER SCIENCE 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 JUL PY 1998 VL 138 IS 2 BP 207 EP 219 DI 10.1006/jssc.1997.7601 PG 13 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 110FM UT WOS:000075369600004 ER PT J AU Woodward, P Vogt, T AF Woodward, P Vogt, T TI Structure of Sn(ND3)(2)F-4 - A molecular precursor for the synthesis of nitride fluorides SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE synthesis; nitride fluorides; crystal structures; neutron diffraction; infrared spectroscopy; Huckel calculations ID VERNIER AB The molecular and crystal structure of Sn(ND3)(2)F-4 has been determined at room temperature using high resolution neutron powder diffraction. The compound crystallizes in a monoclinic unit cell containing two formula units with a = 7.7673(7) Angstrom, b = 6.2765(5) Angstrom, c = 5.1708(4) Angstrom, beta = 102.871(5) degrees, and space-group P2(1)/n. The structure consists of isolated tin-centered octahedra with ammonia groups in trans configuration. The intramolecular stability of this compound has been investigated using Huckel molecular orbital calculations. Compared to Si(NH3)(2)F-4, the metal-nitrogen bonding interaction is found to be stronger, while the metal-fluorine bond is weaker in Sn(ND3)(2)F-4. Due to a different hydrogen bonding network the intermolecular orientation and packing of the octahedral M(NH3)(2)F-4 molecules in Sn(ND3)(2)F-4 is different from the arrangement observed in Si(NH3)(2)F-4. The implications for the use of these compounds as molecular precursors for the synthesis of SiNF and SnNF are discussed. (C) 1998 Academic Press. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Tubingen, Inst Anorgan Chem, D-72076 Tubingen, Germany. RP Vogt, T (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Vogt, Thomas /A-1562-2011 OI Vogt, Thomas /0000-0002-4731-2787 NR 24 TC 7 Z9 7 U1 2 U2 5 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 JUL PY 1998 VL 138 IS 2 BP 350 EP 360 DI 10.1006/jssc.1997.7545 PG 11 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 110FM UT WOS:000075369600025 ER PT J AU Seront, B Wong, TF Caine, JS Forster, CB Bruhn, RL Fredrich, JT AF Seront, B Wong, TF Caine, JS Forster, CB Bruhn, RL Fredrich, JT TI Laboratory characterization of hydromechanical properties of a seismogenic normal fault system SO JOURNAL OF STRUCTURAL GEOLOGY LA English DT Article ID HYDROTHERMAL ALTERATION; PRESSURE; PERMEABILITY; ZONES; EARTHQUAKES; NEVADA; STRESS; ROCKS AB The Stillwater seismogenic normal fault in Dixie Valley. Nevada has been historically active and is located in an al ea of high heat flow and hydrothermal activity. Three primary structural elements are identified in the fault zone: a relatively wide fault core (with breccia pods embedded in cataclasites), a damage zone (with arrays of mesoscopic fractures), and protolith. Hydromechanical properties of representative core samples were characterized in the laboratory. and microstructural analyses were conducted using optical and scanning electron microscopy. When deformed in conventional triaxial compression, dilatancy and brittle fracture were observed in each sample. Samples from the core of the fault were relatively weak, with strengths similar to that of unconsolidated fault gouge, whereas granodiorite samples from the protolith were as weak as the core and damage zone samples were stronger. Permeability is dependent on effective pressure, porosity and connectivity of the pore space, with values ranging over four orders of magnitude among the core samples. The lowest permeability of 3 x 10(-20) m(2) was measured in a fault core sample with a microstructure indicative of implosion brecciation. In conjunction with field measurements. the laboratory data suggest that fluid How and changes in fluid storage are concentrated in the damage zone, with permeability several orders of magnitude higher than the protolith and fault core. Permeability contrast tone order of magnitude) at the core sample scale exists between the cataclasite and implosion breccia in the fault core. Because of dilatancy and poor drainage in the breccia pods, anomalously low pore pressures may develop in localized clusters due to dilatancy hardening during the preseismic period. These clusters of low pore pressure can act similarly to fault jogs, locally inhibiting fault rupture and inducing brecciation when the delayed failure finally occurs by catastrophic implosion. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. Univ Utah, Dept Geol & Geophys, Salt Lake City, UT 84112 USA. Sandia Natl Labs, Geomech Dept, Albuquerque, NM 87185 USA. RP Seront, B (reprint author), SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. OI Caine, Jonathan/0000-0002-7269-6989 NR 33 TC 71 Z9 72 U1 3 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0191-8141 J9 J STRUCT GEOL JI J. Struct. Geol. PD JUL PY 1998 VL 20 IS 7 BP 865 EP 881 DI 10.1016/S0191-8141(98)00023-6 PG 17 WC Geosciences, Multidisciplinary SC Geology GA 109BE UT WOS:000075300700004 ER PT J AU Mochizuki, T Sakurai, Y Shu, D Kuzay, TM Kitamura, H AF Mochizuki, T Sakurai, Y Shu, D Kuzay, TM Kitamura, H TI Design of compact absorbers for high-heat-load X-ray undulator beamlines at SPring-8 SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE undulator beamlines; front ends; high-heat-load components; absorbers AB A compact and high-heat-load absorber for the SPring-8 X-ray undulator beamline has been developed and installed. It consists of an upper heat-absorber part and a lower photon duct part, which are configured together in a water-cooled GlidCop body. The absorber part has a horizontal notch shape and the photon duct part forms a rectangular open channel under the absorber part. Two types of absorber are designed: one, with wire mesh channels, is 386 mm long, 70 mm high and 64 mm wide; the other, with smooth-bore channels, is 610 mm long, 75 mm high and 70 mm wide. Thermal and stress analyses show that they withstand the 12.3 kW heat load and the maximum heat flux of 940 W mm(-2) at normal incidence. C1 JASRI, Kamigori, Hyogo 67812, Japan. RIKEN, Kamigori, Hyogo 67812, Japan. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Mochizuki, T (reprint author), JASRI, Kamigori, Hyogo 67812, Japan. NR 2 TC 12 Z9 12 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD JUL 1 PY 1998 VL 5 BP 1199 EP 1201 DI 10.1107/S0909049598000387 PN 4 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 105ZP UT WOS:000075105500003 PM 16687820 ER PT J AU Zhang, K Rosenbaum, G Bunker, G AF Zhang, K Rosenbaum, G Bunker, G TI Energy-resolving X-ray fluorescence detection using synthetic multilayers SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE fluorescence detectors; X-ray absorption spectroscopy; synthetic multilayers ID ARRAY; EXAFS AB The potential of synthetic multilayers for energy-resolving the X-ray fluorescence in X-ray absorption fine structure (XAFS) experiments is discussed. Two detection systems, one using curved multilayers and the other using graded multilayers to select X-ray fluorescence photons, have been designed to cover a wide energy range with a usefully large solid angle. Such a detector will be more advantageous than the barrel-like crystal-array detector because of the unique properties of synthetic multilayers, such as larger horizontal acceptance angles and bandwidth. In addition, the detector should be much simpler to construct and readily accommodates energy changes, especially the detector using graded multilayers. Comparison of the multilayer array detector with conventional detectors, such as ionization chambers and conventional 13-element Ge detectors, shows that the proposed system will be superior, particularly with the increased photon fluxes available from insertion devices and with decreased sample concentration, since this detection system eliminates the 'bad' photons before they enter any X-ray detector. Consequently, the X-ray detector proper for this system does not suffer from the incident-count-rate bottleneck common to current X-ray fluorescence detectors with energy resolution by signal processing. Thus, this new fluorescence detection system will provide tremendous opportunities for XAFS measurements on dilute systems, such as biological systems, at third-generation synchrotron sources. C1 IIT, Dept Biol Chem & Phys Sci, Chicago, IL 60616 USA. Argonne Natl Lab, Struct Biol Ctr, Argonne, IL 60439 USA. RP Zhang, K (reprint author), IIT, Dept Biol Chem & Phys Sci, Chicago, IL 60616 USA. EM ke@biocat1.iit.edu RI ID, BioCAT/D-2459-2012 NR 15 TC 15 Z9 15 U1 0 U2 5 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD JUL 1 PY 1998 VL 5 BP 1227 EP 1234 DI 10.1107/S0909049597019535 PN 4 PG 8 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 105ZP UT WOS:000075105500009 PM 16687826 ER PT J AU Friedersdorf, FJ Holcomb, GR AF Friedersdorf, FJ Holcomb, GR TI Pin-on-disk corrosion-wear test SO JOURNAL OF TESTING AND EVALUATION LA English DT Article DE wear; abrasion; corrosion; pin-on-disk; tool steel; stainless steel; low-alloy steel; sulfuric acid; sodium sulfate; potentiodynamic scan; testing ID STAINLESS-STEEL AB An electrochemical pin-on-disk corrosion-wear apparatus was developed at the Albany Research Center of the U.S. Department of Energy. The instrument was qualified on a low-alloy T1 tool steel [ASTM A 514] and a 304 stainless steel (Type 304). The apparatus incorporates simple specimen and counterface geometry and is instrumented for simultaneous corrosion and wear testing. The electrochemical and wear parameters of potential, current, charge, sliding speed, frictional force, and normal acceleration can be continuously displayed and recorded. After a break-in period, the electrochemical pin-on-disk produced constant wear rates independent of path length for both ASTM A 514 steel and 304 stainless steel. Results for 304 stainless steel in sulfate solutions show that abrasive wear causes the corrosion potential to shift by 0.4 V in the active direction and the passive current density to increase by three orders of magnitude, compared with the condition of no wear. Current density was a linear function of the sliding speed at a constant applied anodic potential. The open circuit corrosion potential exhibits a decay function behavior with respect to the sliding speed. Volume loss and corrosion measurements showed that mechanical removal of material was responsible for 95% of the corrosion-wear losses for 304 stainless steel. Continual corrosion exposure, however, increased the mechanical removal of material by 35 to 48%. C1 US Dept Energy, Albany Res Ctr, Albany, OR USA. RP Friedersdorf, FJ (reprint author), Bethlehem Steel Corp, Homer Res Labs, Bethlehem, PA 18016 USA. RI Holcomb, Gordon/G-9070-2013 OI Holcomb, Gordon/0000-0003-3542-5319 NR 15 TC 1 Z9 1 U1 0 U2 3 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0090-3973 J9 J TEST EVAL JI J. Test. Eval. PD JUL PY 1998 VL 26 IS 4 BP 352 EP 357 PG 6 WC Materials Science, Characterization & Testing SC Materials Science GA 102DH UT WOS:000074907700008 ER PT J AU Landes, JD Brown, K AF Landes, JD Brown, K TI Results from a round robin on a standard method for measurement of fracture toughness SO JOURNAL OF TESTING AND EVALUATION LA English DT Article DE fracture toughness; test standard; common method; round robin; procedure verification AB A paper round robin was conducted to evaluate the workability and reproducibility of a unified draft fracture toughness test standard titled "Standard Method for Measurement of Fracture Toughness." The paper round robin consisted of 19 records from fracture toughness tests conducted separately from this round-robin exercise. These test records were given to the participants with the requirement that they use the draft standard to evaluate the fracture toughness values from the tests. The round robin was conducted between February 1991 and June 1992. Originally more than 30 organizations were invited to participate; however, only five finally responded with complete analyses of all of the test records. The five participants were all experienced in fracture testing and analyses. To subject the method to an evaluation by persons with less experience, some of the test records were analyzed by graduate students whose only experience with fracture testing and analyses was a course on fracture mechanics. The round robin was conducted on Draft 10 of the proposed standard: "Standard Method for Measurement of Fracture Toughness." This paper contains a brief description of the draft test method, a discussion of the specimens and test records supplied, a brief summary of results, and a discussion of the changes made to the test method as a result of the round-robin exercise. All tests and analyses were conducted using English units; therefore, to accurately transmit the results, English rather than SI are used as the primary units of this paper. C1 Univ Tennessee, Knoxville, TN 37996 USA. Sandia Natl Labs, Mat & Struct Mech Dept, Albuquerque, NM 87185 USA. RP Landes, JD (reprint author), Univ Tennessee, Knoxville, TN 37996 USA. NR 3 TC 3 Z9 3 U1 0 U2 1 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0090-3973 J9 J TEST EVAL JI J. Test. Eval. PD JUL PY 1998 VL 26 IS 4 BP 396 EP 403 PG 8 WC Materials Science, Characterization & Testing SC Materials Science GA 102DH UT WOS:000074907700015 ER PT J AU Adeff, JA Hofler, TJ Atchley, AA Moss, WC AF Adeff, JA Hofler, TJ Atchley, AA Moss, WC TI Measurements with reticulated vitreous carbon stacks in thermoacoustic prime movers and refrigerators SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB Reticulated vitreous carbon has been successfully used as a stack material in thermoacoustic prime movers and refrigerators. It is a rigid glassy carbon material, with a porous spongelike structure. Test results indicate peak pressure amplitudes of up to 32% in a prime mover, and refrigeration performance comparable to that of a traditional plastic roll stack. (C) 1998 Acoustical Society of America. [S0001-4966(98)05505-2]. C1 USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Adeff, JA (reprint author), USN, Postgrad Sch, Dept Phys, Monterey, CA 93943 USA. NR 10 TC 29 Z9 32 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUL PY 1998 VL 104 IS 1 BP 32 EP 38 DI 10.1121/1.424055 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZY164 UT WOS:000074592700004 ER PT J AU Candy, JV Sullivan, EJ AF Candy, JV Sullivan, EJ TI Broadband model-based processing for shallow ocean environments SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID DOMAIN SIGNAL TRANSMISSION; SOURCE LOCALIZATION; TIME-DOMAIN; WAVE-GUIDE; SOURCE LOCATION; TRANSIENT; WATER AB Most acoustic sources found in the ocean environment are spatially complex and broadband, In the case of shallow water propagation, these source characteristics complicate the analysis of received acoustic data considerably. A common approach to the broadband problem is to decompose the received signal into a set of narrow-band lines. This then allows the problem to be treated as a multiplicity of narrow-band problems. Here a model-based approach is developed for the processing of data received on a vertical array from a broadband source where it is assumed that the propagation is governed by the normal-mode model. The goal of the processor is to provide an enhanced (filtered) version of the pressure at the array and the modal functions. Thus a pre-processor is actually developed, since one could think of several applications for these enhanced quantities such as localization, modal estimation, etc. It is well-known that in normal-mode theory a different modal structure evolves for each temporal frequency; thus it is not surprising that the model-based solution to this problem results in a scheme that requires a "bank" of narrow-band model-based processors-each with its own underlying modal structure for the narrow frequency band it operates over. The "optimal" Bayesian solution to the broadband pressure field enhancement and modal function extraction problem is developed. It is shown how this broadband processor can be implemented (using a suboptimal scheme) in pseudo real time due to its inherent parallel structure. A set of noisy broadband data is synthesized to demonstrate how to construct the processor and achieve a minimum variance (optimal Bayesian) design. It is shown that both broadband pressure-field and modal function estimates can be extracted illustrating the feasibility of this approach. (C) 1998 Acoustical Society of America. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Undersea Warfare Ctr, Newport, RI 02841 USA. RP Candy, JV (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-156, Livermore, CA 94550 USA. NR 31 TC 5 Z9 10 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUL PY 1998 VL 104 IS 1 BP 275 EP 287 DI 10.1121/1.423278 PG 13 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZY164 UT WOS:000074592700032 ER PT J AU Black, F Tejada, S Gurevich, M AF Black, F Tejada, S Gurevich, M TI Alternative fuel motor vehicle tailpipe and evaporative emissions composition and ozone potential SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID REACTIVITY AB The 1988 Alternative Motor Fuels Act and the 1990 Clean Air Act Amendments require examination of the potential to favorably influence air quality by changing the composition of motor vehicle fuels. Motor vehicle tailpipe and evaporative emissions were characterized using laboratory simulations of roadway driving conditions and a variety of vehicle-fuel technologies (reformulated gasoline (RFG), methanol (M85), ethanol (E85), and natural gas (CNG)). Speciated organic compound (with Carter MIR ozone potential), CO, and NOx emission rates and fuel economy were characterized. The Carter MIR clone potential of combined Federal Test Procedure (FTP) tailpipe and evaporative emissions was reduced more than 90% with CNG relative to RFG, M85, and E85 fuels. FTP toxic compound emissions (benzene, formaldehyde, acetaldehyde, and 1,3-butadiene) were greater with M85 and E85 fuels than with RFG fuel, and less with CNG fuel than RFG fuel. The most abundant toxic compound was benzene with RFG fuel, formaldehyde with M85 fuel, and acetaldehyde with E85 fuel. FTP MPG fuel economies were reduced with M85 and E85 fuels relative to RFG fuel, consistent with their lower BTU/gal. Energy efficiencies (BTU/mi) were improved with all the alternative fuels relative to RFG. Carter MIR ozone potential was generally reduced with the alternative fuels relative to RFG fuel under REP05 (high speeds and acceleration rates) driving conditions (most significantly with CNG). Toxic aldehyde emissions were reduced under REP05 conditions relative to FTP conditions with all the tested fuels, and toxic benzene emissions were elevated under high acceleration conditions. C1 US EPA, Natl Exposure Res Lab, Source Apportionment & Characterizat Branch, Res Triangle Pk, NC 27711 USA. US DOE, Washington, DC USA. RP Black, F (reprint author), US EPA, Natl Exposure Res Lab, Source Apportionment & Characterizat Branch, MD-48, Res Triangle Pk, NC 27711 USA. NR 33 TC 23 Z9 23 U1 1 U2 9 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 JUL PY 1998 VL 48 IS 7 BP 578 EP 591 PG 14 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 106GH UT WOS:000075121200001 PM 9706038 ER PT J AU Plucknett, KP Becher, PF Waters, SB AF Plucknett, KP Becher, PF Waters, SB TI Flexure strength of melt-infiltration-processed titanium carbide nickel aluminide composites SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID MECHANICAL-PROPERTIES; TERNARY ADDITION; NI3AL; DUCTILITY; BEHAVIOR; ELEMENTS; ALLOYS; BORON; SIZE AB TiC/Ni3Al composites were prepared using a simple melt-infiltration process, performed at either 1300 degrees or 1400 degrees C, with the Ni(3)AI content varied over the range of 8-25 vol%, Densities >96% of theoretical were obtained for all composites. Four-point flexure strengths at 22 degrees C increased as the Ni(3)AI content increased (i.e., similar to 1100 MPa at 20 vol% Ni(3)AI), with the highest strengths being observed for composites processed at 1300 degrees C, because of reduced TiC grain size. Strengths at elevated temperatures increased with test temperature, up to similar to 1000 degrees C, As with the yielding behavior of the Ni,AI alloy used, a maximum in composite strength (similar to 1350 MPa) versus temperature was observed; this occurred at 950 degrees C, which is similar to 300 degrees C above the yield maximum for the alloy. Extensive plastic strain was achieved in the composites even at high loading rates at 1135 degrees C, and the yield stress was dependent on the applied loading rate. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Plucknett, KP (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 27 TC 28 Z9 30 U1 1 U2 8 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 JUL PY 1998 VL 81 IS 7 BP 1839 EP 1844 PG 6 WC Materials Science, Ceramics SC Materials Science GA 100UH UT WOS:000074833400016 ER PT J AU Schneibel, JH Sabol, SM Morrison, J Ludeman, E Carmichael, CA AF Schneibel, JH Sabol, SM Morrison, J Ludeman, E Carmichael, CA TI Cyclic thermal shock resistance of several advanced ceramics and ceramic composites SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID ALUMINA AB The cyclic thermal shock behavior of two Si3N4 ceramics, two SiC-whisker-reinforced alumina composites (Al2O3/SiCw), a SiC-particulate-reinforced alumina (Al2O3/SiCp), and an alumina continuously reinforced with SiC fibers (Al2O3/SiCf) composite has been studied. Specimens were repeatedly quenched from 1473 K into a fluidized bed with a heat transfer coefficient of 1400 W/(K . m(2)) [250 Btu/(h . ft(2). F)]. The thermal shock damage was assessed by room-temperature flexure strength measurements. Si3N4 and Al2O3/SiCp showed no noticeable damage after 100 cycles, whereas Al2O3/SiCw and Al2O3/SiCf degraded substantially. The experimental results are discussed and rationalized in terms of finite element simulations and microstructural observations. Our analysis suggests that the thermal shock performance of other materials may be estimated from comparisons with the present work. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Westinghouse Power Generat, Orlando, FL 32826 USA. RP Schneibel, JH (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 10 TC 15 Z9 15 U1 0 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 JUL PY 1998 VL 81 IS 7 BP 1888 EP 1892 PG 5 WC Materials Science, Ceramics SC Materials Science GA 100UH UT WOS:000074833400023 ER PT J AU Becher, PF Lin, HT More, KL AF Becher, PF Lin, HT More, KL TI Lifetime-applied stress response in air of a SiC-based Nicalon-fiber-reinforced composite with a carbon interfacial layer: Effects of temperature (300 degrees to 1150 degrees C) SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID MATRIX COMPOSITES; STRENGTH AB The lifetimes in air as a function of applied flexure stress and temperature (300-1150 degrees C) are described for a Si-O-C based (Nicalon) fiber plain-weave cloth reinforced SiC-matrix composite (similar to 7% closed porosity) with an similar to 0.3 mu m thick carbon interfacial layer. The measured lifetimes of both samples with and without an external SiC seal coating were similar and decreased with applied flexural stress (for stresses greater than -90 MPa) and with temperature. At temperatures of greater than or equal to 600 degrees C, the external CVD SIC coating had negligible effect on the lifetimes; however, at 425 degrees C, a detectable improvement in the lifetime was observed with an external SiC coating. When the applied stress was decreased below an apparent "threshold stress" (e.g., similar to 90 MPa) for tests conducted at temperatures less than or equal to 950 degrees C, no failures were observed for times of greater than or equal to 1000 h, Electron microscopy observations show that the interfacial carbon layer is progressively removed during tests at 425 degrees and 600 degrees C, In these cases, failure is associated with fiber failure and pullout. At 950 degrees and 1150 degrees C, the carbon interface layer is eliminated and replaced by a thick silica layer due to the oxidation of the Nicalon fiber and the SiC matrix. This results in embrittling the composite. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Becher, PF (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 24 TC 9 Z9 9 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 1998 VL 81 IS 7 BP 1919 EP 1925 PG 7 WC Materials Science, Ceramics SC Materials Science GA 100UH UT WOS:000074833400028 ER PT J AU Bae, YW Lee, WY Besmann, TM Cavin, OB Watkins, TR AF Bae, YW Lee, WY Besmann, TM Cavin, OB Watkins, TR TI Effects of processing parameters on alumina coatings deposited on nickel substrates by reacting aluminum chloride and hydrogen/carbon dioxide gas mixtures SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CHEMICAL VAPOR-DEPOSITION AB Pure nickel coupons were used as substrates in the deposition of alumina (Al2O3) from the reaction of aluminum chloride (AlCl3) with hydrogen/carbon dioxide gas mixtures in the temperature range of 954 degrees-1100 degrees C and system pressures of 2.7-13.3 kPa, The apparent activation energy estimated from the coating growth rate averaged 320 kJ/mol at 13.3 kPa, At temperatures <1000 degrees C, transition theta, kappa, and delta modifications were codeposited with alpha-Al2O3, whereas single-phase alpha-Al2O3 was deposited at higher temperatures. At high AlCl3 partial pressures, nickel aluminide phases were sometimes codeposited with Al2O3, which was attributed to the reaction of AlCl3 with the nickel substrate in the presence of hydrogen gas. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Bae, YW (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Watkins, Thomas/D-8750-2016 OI Watkins, Thomas/0000-0002-2646-1329 NR 14 TC 16 Z9 16 U1 0 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 1998 VL 81 IS 7 BP 1945 EP 1948 PG 4 WC Materials Science, Ceramics SC Materials Science GA 100UH UT WOS:000074833400033 ER PT J AU Spearing, DR Huang, JY AF Spearing, DR Huang, JY TI Zircon synthesis via sintering of milled SiO2 and ZrO2 SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID WEAPONS PLUTONIUM; RADIATION-DAMAGE; ZRSIO4 AB The formation of zircon (ZrSiO4) via sintering of milled SiO2 and ZrO2 powders was studied, and the effects of slurry vs dry milling, sintering time, and particle size on zircon yield were examined. It was found that very high zircon yields could be obtained via slurry milling, cold pressing, and sintering of the oxide precursors. The controlling factor in determining zircon yield was found to be the particle size of the SiO2 and ZrO2 powders. Zircon yield as a function of sintering time was examined, and found to be similar to previous studies in which sol-gel precursors seeded with zircon were used. SEM studies reveal a homogeneous product with particle sizes on the order of 1-5 mu m. It was found that complete reaction to zircon can be achieved from a once-through milling, pressing, and sintering process of SiO2-ZrO2 powders. C1 Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Spearing, DR (reprint author), Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RI Huang, Jianyu/C-5183-2008 NR 10 TC 13 Z9 15 U1 0 U2 5 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 JUL PY 1998 VL 81 IS 7 BP 1964 EP 1966 PG 3 WC Materials Science, Ceramics SC Materials Science GA 100UH UT WOS:000074833400038 ER PT J AU Krishnan, S Ansell, S Price, DL AF Krishnan, S Ansell, S Price, DL TI X-ray diffraction from levitated liquid yttrium oxide SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB We report the first measurements of the structure factor, S(Q), and radial distribution function, G(r), of yttrium oxide in the normal and supercooled liquid states in the temperature range 2500-3100 K, Measurements were obtained by synchrotron X-ray scattering on levitated, laser-heated liquid specimens, At temperatures far in excess of the melting point, the first and second coordination shells begin to merge, indicative of increased ionicity in the liquid. As the temperature is lowered into the supercooled region, there is substantial sharpening and strengthening in the first peaks in both see, and G(r), Supercooling causes a decrease in the first shell coordination and Il values together with an increase in the Y-O interionic distance. C1 Certainerless Res Inc, Evanston, IL 60201 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Krishnan, S (reprint author), Certainerless Res Inc, Evanston, IL 60201 USA. RI Price, David Long/A-8468-2013 NR 16 TC 19 Z9 19 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 1998 VL 81 IS 7 BP 1967 EP 1969 PG 3 WC Materials Science, Ceramics SC Materials Science GA 100UH UT WOS:000074833400039 ER PT J AU Levanon, H Galili, T Regev, A Wiederrecht, GP Svec, WA Wasielewski, MR AF Levanon, H Galili, T Regev, A Wiederrecht, GP Svec, WA Wasielewski, MR TI Determination of the energy levels of radical pair states in photosynthetic models oriented in liquid crystals with time-resolved electron paramagnetic resonance SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ARTIFICIAL PHOTOSYNTHESIS; TRANSFER RATES; TRIPLET-STATE; SPECTROSCOPY; DYNAMICS; ASSEMBLIES AB We report the results of time-resolved electron paramagnetic resonance (TREPR) studies of photoinduced charge separation in a series of biomimetic supramolecular compounds dissolved in oriented liquid crystal solvents. The molecules contain a chlorophyll-like (zinc 9-desoxomethylpyropheophorbide a) electron donor, D (ZC), and two electron accepters with different reduction potentials, i.e., pyromellitimide, A(1) (PI), and 1,8:4,5-naphthalenediimide, A(2) (NI). The compounds investigated are ZCPI, ZCNI, and ZCPINI, and they have small but well-defined differences of their ion-pair energies. Temperature-dependent TREPR studies on this series of compounds permit the determination of the radical pair energy levels as the solvent reorganization energy increases from the low-temperature crystalline phase, through the soft glass phase, to the nematic phase of the liquid crystal. As the temperature is increased, the radical pair with the lowest energy is the first to exhibit triplet-initiated charge separation as the solvent reorganization energy increases in the liquid crystal. The energy levels of the radical pairs and the solvent reorganization energy are determined by using the known singlet: and triplet excited state energy levels of ZC, the electrochemically determined relative energies between the radical ion pairs in polar isotropic solvents, and the TREPR data. All these yield information about the ordering of the radical ion pair energy levels relative to the excited-state energy levels of ZC. C1 Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. Hebrew Univ Jerusalem, Farkas Ctr Light Induced Proc, IL-91904 Jerusalem, Israel. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. RP Levanon, H (reprint author), Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. NR 30 TC 51 Z9 51 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JUL 1 PY 1998 VL 120 IS 25 BP 6366 EP 6373 DI 10.1021/ja980409c PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA ZY238 UT WOS:000074600100021 ER PT J AU McLuckey, SA AF McLuckey, SA TI Focus on oligonucleotides SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Editorial Material C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP McLuckey, SA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI McLuckey, Scott/B-2203-2009 OI McLuckey, Scott/0000-0002-1648-5570 NR 0 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD JUL PY 1998 VL 9 IS 7 BP 659 EP 659 DI 10.1016/S1044-0305(98)00054-3 PG 1 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA ZU137 UT WOS:000074166000001 ER PT J AU Gorshkov, MV Tolic, LP Udseth, HR Anderson, GA Huang, BM Bruce, JE Prior, DC Hofstadler, SA Tang, LA Chen, LZ Willett, JA Rockwood, AL Sherman, MS Smith, RD AF Gorshkov, MV Tolic, LP Udseth, HR Anderson, GA Huang, BM Bruce, JE Prior, DC Hofstadler, SA Tang, LA Chen, LZ Willett, JA Rockwood, AL Sherman, MS Smith, RD TI Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry at 11.5 tesla: Instrument design and initial results SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID LARGE MOLECULES; MAGNETIC-FIELD; RESOLUTION; TIME; SPECTROSCOPY; BIOMOLECULES; AXIALIZATION; BIOPOLYMERS; PRINCIPLES; EXCITATION AB Initial results obtained using a new electrospray ionization (ESI) Fourier transform ion cyclotron resonance (FTICR) mass spectrometer operated at a magnetic field 11.5 tesla are presented. The new instrument utilized an electrostatic ion guide between the ESI source and FTICR trap that provided up to 5% overall transmission efficiency for Light ions and up to 30% efficiency for heavier biomolecules. The higher magnetic field in combination with an enlarged FTICR ion trap made it possible to substantially improve resolving power and operate in a more robust fashion for large biopolymers compared to lower field instruments. Mass resolution up to 10(6) has been achieved for intermediate size biopolymers such as bovine ubiquitin (8.6 kDa) and bovine cytochrome c (12.4 kDa) without the use of frequency drift correction methods. A mass resolution of 370,000 has been demonstrated for isotopically resolved molecular ions of bovine serum albumin (66.5 kDa). Comparative measurements were made with the same spectrometer using a lower field 3.5-tesla magnet allowing the performance gains to be more readily quantified. Further improvements in pumping capacity of the vacuum system and efficiency of ion transmission from the source are expected to lead to further substantial sensitivity gains. (C) 1998 American Society for Mass Spectrometry. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999,MS K8-98, Richland, WA 99352 USA. RI Gorshkov, Mikhail/E-8522-2010; Smith, Richard/J-3664-2012; Gorshkov, Mikhail/N-4984-2013 OI Smith, Richard/0000-0002-2381-2349; Gorshkov, Mikhail/0000-0001-9572-3452 NR 29 TC 45 Z9 47 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD JUL PY 1998 VL 9 IS 7 BP 692 EP 700 DI 10.1016/S1044-0305(98)00037-3 PG 9 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA ZU137 UT WOS:000074166000006 PM 9879379 ER PT J AU Miller, MA Jensen, MP Clothiaux, EE AF Miller, MA Jensen, MP Clothiaux, EE TI Diurnal cloud and thermodynamic variations in the stratocumulus transition regime: A case study using in situ and remote sensors SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID MARINE BOUNDARY-LAYER; RADIATION BUDGET EXPERIMENT; ASTEX; PARAMETERIZATION AB Radiosonde, in situ, and surface-based remote sensor data from the Atlantic Stratocumulus Transition Experiment are used to study the diurnal cycle of cloud and thermodynamic structure. A cloud layer and decoupled subcloud layer separated by a stable transition layer, often observed in the vicinity of cumulus cloud base, characterizes the thermodynamic structure during the study period. The mode of cloud structure is cumulus with bases below decoupled stratus. Data are presented that support the hypothesis that diurnal variations in cumulus development are modulated by the stability in the transition layer. The frequency of cumulus convection decreases during the afternoon, but mesoscale regions of vigorous cumulus with cloud tops overshooting the base of the trade inversion and increased surface drizzle rates are present during the late afternoon and early evening, when the transition layer is the most stable. It is postulated that mesoscale organization may be required to accumulate enough water vapor in the subcloud layer to produce the convective available potential energy needed for developing cumulus to overcome transition layer stability. The mesoscale regions appear to fit the description of cyclic cumulus convection proposed in a previous study, and this theory is expanded to account for diurnal variations in the stability of the transition layer. The occurrence of these mesoscale clusters of vigorous convection makes it difficult to determine if the latent heat flux in the cloud layer has actually decreased in the late afternoon and early evening, when the transition layer is the most stable. Liquid water structure was examined and no pronounced diurnal signal was found. Results showed that clouds thicker than approximately 450 m tended to have subadiabatic integrated liquid water contents, presumably due to evaporation of drizzle in the subcloud layer, removal of liquid water at the surface, and the evaporation of cloud water at cloud top. A significant fraction of clouds less than 450 m thick produced liquid water contents that were greater than adiabatic, and there may be a physical mechanism that could produce such values in this cloud system (i.e., lateral detrainment of cloud water from convective elements mixing with existing liquid water in decoupled stratus or with liquid water detrained by nearby convective elements). Unfortunately, instrument limitations may have also produced these greater-than-adiabatic values and the extent of instrument artifacts in these results is unclear. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. RP Miller, MA (reprint author), Brookhaven Natl Lab, Dept Appl Sci, POB 5000, Upton, NY 11973 USA. NR 21 TC 23 Z9 23 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD JUL 1 PY 1998 VL 55 IS 13 BP 2294 EP 2310 DI 10.1175/1520-0469(1998)055<2294:DCATVI>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZZ230 UT WOS:000074708600004 ER PT J AU Kim, J Song, X Kinoshita, K Madou, M White, B AF Kim, J Song, X Kinoshita, K Madou, M White, B TI Electrochemical studies of carbon films from pyrolyzed photoresist SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID DIAMOND-LIKE CARBON; AMORPHOUS-CARBON; GLASSY-CARBON; DEPOSITION; ELECTRODES; OXYGEN; ARC AB Carbon film electrodes were prepared by pyrolysis of photoresists on silicon-wafers at temperatures ranging from 600 to 1100 degrees C. The physical properties of the carbon films were characterized by scanning and transmission electron microscopies, thermal gravimetric analysis, and four-point probe electrical resistivity measurements. The electrochemical properties of the carbon films were investigated by cyclic voltammetry to observe the kinetics of the Fe(CN)(6)(4-)/Fe(CN)(6)(3-) redox couple. The carbon film electrodes prepared at temperatures greater than or equal to 700 degrees C showed electrochemical behavior Similar to that of glassy carbon. Better electrocatalytic behavior was obtained with carbon films prepared at the higher pyrolysis temperatures which is attributed to different film compositions at different pyrolysis temperatures. The electrochemical properties of the:carbon film electrodes are very stable, exhibiting reproducible behavior even after storing at room temperature in air for 3 months. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley Sensor & Actuator Ctr, Berkeley, CA 94720 USA. RP Kim, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RI Madou, Marc/E-5869-2013 OI Madou, Marc/0000-0003-4847-3117 NR 35 TC 88 Z9 89 U1 3 U2 29 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 JUL PY 1998 VL 145 IS 7 BP 2314 EP 2319 DI 10.1149/1.1838636 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZX043 UT WOS:000074474500016 ER PT J AU Song, L Evans, JW AF Song, L Evans, JW TI The thermal stability of lithium polymer batteries SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ELECTROLYTE BATTERIES; TEMPERATURE; MODULE AB The electrical. (ionic) conductivity of polymer electrolytes for lithium-polymer cells increases greatly with increasing temperature (in contrast to the thermal conductivity). This paper examines, by both a Linear perturbation analysis and by numerical calculation, an instability that could arise from this temperature dependence. The instability is one where a local perturbation to a higher temperature results in higher electrical conductivity and therefore the passage of more current in this region with an attendant increase in heat generation. If this excess heat generation cannot be conduced into adjacent cooler regions, instability (growth of the perturbation) results. The numerical calculations were carried out for constant potential drop across the electrolyte, for constant mean current density, and for constant mean power discharge schedules. The calculations suggest that this instability is unlikely for small batteries (of the order of 0.1 m in the directions parallel to the electrodes) but may occur for larger batteries such as those intended for use in an electric vehicle. However, the growth rates of the perturbations do not appear to be high. Changes in cell materials /thickness have little effect on the instability. The Linear perturbation analysis is in approximate agreement with the numerical calculations. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Energy & Environm, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Song, L (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Energy & Environm, Berkeley, CA 94720 USA. NR 17 TC 12 Z9 12 U1 0 U2 4 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 JUL PY 1998 VL 145 IS 7 BP 2327 EP 2334 DI 10.1149/1.1838638 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZX043 UT WOS:000074474500018 ER PT J AU Kostecki, R Richardson, T McLarnon, D AF Kostecki, R Richardson, T McLarnon, D TI Photochemical and photoelectrochemical behavior of a novel TiO2/Ni(OH)(2) electrode SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ATOMIC-FORCE MICROSCOPY; TIO2 COATING FILMS; SEMICONDUCTOR PARTICLES; NICKEL; OXIDE; REDUCTION; WO3; MECHANISM; COLLOIDS; CLUSTERS AB Transparent Ni(OH)(2) films were electrochemically deposited onto TiO2 layers which had been formed on conductive glass. This optically transparent composite electrode exhibited strong, reversible photochromic and electrochromic properties when either illuminated by a 75 W Xe lamp at open circuit or anodically polarized in 1.0 M aqueous NaOH electrolyte. The extent of electrode darkening depended on the intensity of UV light, exposure time, and applied potential. Electrochemical and optical-absorption measurements indicated that W-photogenerated holes in the TiO2 valence band recombined with electrons from the electrochromic Ni(OH)(2) layer, which consequently oxidized the Ni(OH)(2) tb NiOOH and darkened the composite electrode. Because the darkening process occurred only on the specific electrode areas which were exposed to Light, nonuniform illumination produced a patterned optical state of the;electrode. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Kostecki, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 37 TC 24 Z9 24 U1 1 U2 20 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 JUL PY 1998 VL 145 IS 7 BP 2380 EP 2385 DI 10.1149/1.1838647 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZX043 UT WOS:000074474500027 ER PT J AU Wolverton, C Zunger, A AF Wolverton, C Zunger, A TI Prediction of Li intercalation and battery voltages in layered vs. cubic LixCoO2 SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID LASER-ABLATION DEPOSITION; SECONDARY LITHIUM CELLS; LICOO2; OXIDES; SPINEL; DENSITY; LINIO2; STATE; GAS AB It is now possible to use a quantum-mechanical electronic structure theory of solids and derive, completely from "first-principles,'' the voltage of a battery based on intercalation reaction energetics. Using such techniques, we investigate the structural stability, intercalation energies, and battery voltages of the two observed ordered phases ("layered" and cubic) of LiCoO2. We perform calculations for not only fully lithiated LiCO2, but also fully delithiated square CoO2 and partially delithiated Li0.5CoO2. Our calculations demonstrate that removal of Li from the cubic phase results in movement of the Li atoms from their original octahedral sites-to tetrahedral sites, forming a low-energy LiCo2O4 spine structure. The energetics of the spinel phase are shown to account for the observed marked differences in battery voltages between the cubic and layered phases of LiCoO2. A small energy barrier exists for Li motion between octahedral and tetrahedral sites, thus indicating the metastability of the high-energy octahedral sites. Finally, we point out a possible pressure-induced layered --> cubic transition in LiCoO2. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wolverton, C (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Wolverton, Christopher/B-7542-2009; Zunger, Alex/A-6733-2013 NR 32 TC 88 Z9 90 U1 3 U2 40 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 EI 1945-7111 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JUL PY 1998 VL 145 IS 7 BP 2424 EP 2431 DI 10.1149/1.1838653 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZX043 UT WOS:000074474500033 ER PT J AU Shida, K Hoover, WG AF Shida, K Hoover, WG TI Maxwell's thermal creep in two space dimensions SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Article DE statistical mechanics; molecular dynamics; kinetic theory; convection; converting heat to work AB "Thermal Creep" is a steady streaming motion. induced by a temperature gradient parallel to a fluid boundary, in the absence of gravity. Thermal creep has been studied by Maxwell, analyzed by Kennard, and simulated by Ibsen: Soto, and Cordero. Here we report several two-dimensional simulations. We find that the creep velocity is sensitive to the imposed macroscopic boundary conditions and that the agreement with existing theoretical predictions is only semiquantitative. C1 Univ Calif Davis Livermore, Dept Appl Sci, Livermore, CA 94551 USA. Musashi Inst Technol, Setagaya Ku, Tokyo 158, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Shida, K (reprint author), Univ Calif Davis Livermore, Dept Appl Sci, Livermore, CA 94551 USA. EM shida@cs.musashi-tech.ac.jp NR 6 TC 5 Z9 5 U1 0 U2 0 PU PHYSICAL SOC JAPAN PI TOKYO PA YUSHIMA URBAN BUILDING 5F, 2-31-22 YUSHIMA, BUNKYO-KU, TOKYO, 113-0034, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD JUL PY 1998 VL 67 IS 7 BP 2277 EP 2280 DI 10.1143/JPSJ.67.2277 PG 4 WC Physics, Multidisciplinary SC Physics GA 104UZ UT WOS:000075035400027 ER PT J AU Wenski, TE Olson, T Rettner, CT Garcia, AL AF Wenski, TE Olson, T Rettner, CT Garcia, AL TI Simulations of air slider bearings with realistic gas-surface scattering SO JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB We have calculated the pressure distribution for an infinitely wide plane slider air bearing by using a particle-based direct simulation Monte Carlo method. These simulations include a sophisticated gas-surface scattering model and take measured accommodation coefficients as inputs. Our results are in good agreement with the molecular gas lubrication theory of Fukui and Kaneko for both glass and disk-drive surfaces. C1 Lightwave Elect, Div Res & Dev, Mt View, CA 95112 USA. Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. IBM Corp, Almaden Res Ctr, Div Res, San Jose, CA 95112 USA. Lawrence Berkeley Lab, Ctr Comp Sci & Engn, Berkeley, CA USA. San Jose State Univ, Dept Phys, San Jose, CA 95192 USA. RP Wenski, TE (reprint author), Lightwave Elect, Div Res & Dev, Mt View, CA 95112 USA. NR 13 TC 4 Z9 4 U1 1 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 JUL PY 1998 VL 120 IS 3 BP 639 EP 641 DI 10.1115/1.2834599 PG 3 WC Engineering, Mechanical SC Engineering GA 102NQ UT WOS:000074930900033 ER PT J AU Madden, HH Landers, R Kleiman, GG Zehner, DM AF Madden, HH Landers, R Kleiman, GG Zehner, DM TI Characteristic losses in metals: Al, Be, and Ni SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article ID ENERGY-LOSS SPECTROSCOPY; APPEARANCE POTENTIAL SPECTROSCOPY; QUANTITATIVE-ANALYSIS; LOSS SPECTRA; REFLECTION; PHOTOEMISSION; BIS AB Information about the occupied portion of the surface density of states of materials can be derived from electron-excited Auger electron spectroscopy (AES), which is a standard experimental technique in most surface science laboratories. Surface sensitive experimental techniques that provide information regarding the unoccupied portion of the surface density of states are often not standard and are not so readily available. Here we explore the possibility of utilizing the same experimental equipment as in AES to derive information about the unoccupied portion of the surface density of states from a characteristic loss spectroscopy, in particular, from core-level inelastic electron-scattering spectroscopy (CLIESS). An important application of this technique is in comparative studies. CLIESS spectra from clean surfaces of aluminum, beryllium and nickel are presented. These data were taken in the first-derivative mode using the reflection of monoenergetic primary beams of 450 eV energy for Be, and 300 eV for Al and Ni. The Al and Be spectra had to be extracted from overlapping plasmon signals using synthesized plasmon spectra based on the behavior of these spectra between the elastic peak energy and the respective core level threshold energies. After applying loss-deconvolution techniques to remove secondary loss spectral distortions, integral spectra were obtained which compared well to corresponding experimental soft x-ray absorption and transmission electron-energy loss data as well as to theoretical calculations of the unoccupied density-of-states for these materials. Comparison similarities as well as some differences are discussed. Finally, in order to illustrate the potential these signals have in serving as ''fingerprints'' of surface chemistry, derivative metal-CLIESS curves for the three oxide surfaces of the metals are also presented. (C) 1998 American Vacuum Society. [S0734-2101 (98)00504-1]. C1 Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13081970 Campinas, SP, Brazil. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Landers, R (reprint author), Univ Estadual Campinas, Inst Fis Gleb Wataghin, Caixa Postal 6165, BR-13081970 Campinas, SP, Brazil. EM landers@ifi.unicamp.br RI LANDERS, Richard/C-7472-2013; Inst. of Physics, Gleb Wataghin/A-9780-2017 NR 49 TC 2 Z9 2 U1 1 U2 5 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 EI 1520-8559 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD JUL-AUG PY 1998 VL 16 IS 4 BP 2595 EP 2603 DI 10.1116/1.581388 PG 9 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700091 ER PT J AU Blain, MG Jarecki, RL Simonson, RJ AF Blain, MG Jarecki, RL Simonson, RJ TI Chemical downstream etching of tungsten SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID MIXTURES; SURFACES AB The downstream etching of tungsten and tungsten oxide has been investigated. Etching of chemical vapor deposited tungsten and e-beam deposited tungsten oxide samples was performed using atomic fluorine generated by a microwave discharge of argon and NF3. Etching was found to be highly activated with activation energies approximated to be 6.0 +/- 0.5 kcal/mol and 5.4 +/- 0.4 kcal/mol for W and WO3, respectively. In the case of F etching of tungsten, the addition of undischarged nitric oxide (NO) directly into the reaction chamber results in the competing effects of catalytic etch rate enhancement and the formation of a nearly stoichiometric WO3 passivating tungsten oxide film, which ultimately stops the etching process. For F etching of tungsten oxide, the introduction of downstream NO reduces the etch rate. (C) 1998 American Vacuum Society. [S0734-2101(98)00404-7]. C1 Sandia Natl Labs, Microelect Dev Lab, Albuquerque, NM 87185 USA. RP Blain, MG (reprint author), Sandia Natl Labs, Microelect Dev Lab, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 4 Z9 4 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2115 EP 2119 DI 10.1116/1.581511 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700017 ER PT J AU Wang, JJ Lambers, ES Pearton, SJ Ostling, M Zetterling, CM Grow, JM Ren, F Shul, RJ AF Wang, JJ Lambers, ES Pearton, SJ Ostling, M Zetterling, CM Grow, JM Ren, F Shul, RJ TI Inductively coupled plasma etching of bulk 6H-SiC and thin-film SiCN in NF3 chemistries SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID SILICON-CARBIDE; POWER DEVICES; SEMICONDUCTOR AB A parametric study of the etching characteristics of 6H p(+) and n(+) SiC and thin-film SiC0.5N0.5 in inductively coupled plasma (ICP) NF3/O-2 and NF3/Ar discharges has been performed. The etch rates in both chemistries increase monotonically with NF3 percentage and rf chuck power. The etch rates go through a maximum with increasing ICP source power, which is explained by a trade-off between the increasing ion flux and the decreasing ion energy. The anisotropy of the etched features is also a function of ion flux, ion energy and atomic fluorine neutral concentration. Indium-tin-oxide masks display relatively good etch selectivity over SiC (maximum of similar to 70:1), while photoresist etches more rapidly than SiC. The surface roughness of SiC is essentially independent of plasma composition for NF3/O-2 discharges, while extensive surface degradation occurs for SiCN under high NF3:O-2 conditions. (C) 1998 American Vacuum Society. [S0734-2101(98) 10104-5]. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Royal Inst Technol, S-16428 Kista, Sweden. New Jersey Inst Technol, Newark, NJ 07102 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wang, JJ (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. RI Zetterling, Carl-Mikael/E-5764-2015 OI Zetterling, Carl-Mikael/0000-0001-8108-2631 NR 34 TC 49 Z9 50 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2204 EP 2209 DI 10.1116/1.581328 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700029 ER PT J AU Meeks, E Ho, P Ting, AL Buss, RJ AF Meeks, E Ho, P Ting, AL Buss, RJ TI Simulations of BCl3/Cl-2/Ar plasmas with comparisons to diagnostic data SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID INDUCTIVELY-COUPLED PLASMA; 2-DIMENSIONAL FLUID MODEL; COLLISION CROSS-SECTIONS; REFERENCE CELL; CHLORINE; TEMPERATURE; DENSITY; ARGON AB A reaction mechanism is reported that describes BCl3/CI2/Ar plasmas used in the etching of metal lines in microelectronics fabrication processes. Although many of the fundamental electron-impact cross sections for this system are not well known, a reasonable set of reaction paths and rate coefficients has been derived to describe low-pressure reactors with high plasma density. The reaction mechanism describes 59 possible gas-phase events and 18 plasma-surface interactions. A well-mixed reactor model is used to develop the reaction set and to test it against absolute experimental measurements of electron and Cl- densities, as well as relative measurements of BCl and Cl radicals in an inductively coupled research reactor. The experimental data cover a wide range of operating conditions and gas mixtures. The model provides quantitative agreement with measurements over the whole range of conditions and diagnostics, capturing most of the observed trends. in addition, the model predicts relative ion ratios and Cl/Cl-2 density ratios as measured by molecular beam mass spectrometry. Comparisons of results from the zero-dimensional model and a two-dimensional continuum plasma model, using the same reaction mechanisms, further validate the chemistry set and show the strengths and weaknesses of the well-stirred reactor approach. Sensitivity analysis shows the dominant reactions contributing to model predictions of species densities. (C) 1998 American Vacuum Society. [S0734-2101(98)09904-7]. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Meeks, E (reprint author), React Design, 6500 Dublin Blvd, Dublin, CA 94568 USA. EM pho@sandia.gov NR 49 TC 62 Z9 62 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2227 EP 2239 DI 10.1116/1.581332 PG 13 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700033 ER PT J AU Ferry, D Suzanne, J Panella, V Barbieri, A Van Hove, MA Biberian, JP AF Ferry, D Suzanne, J Panella, V Barbieri, A Van Hove, MA Biberian, JP TI MgO(100) surface relaxation by symmetrized automated tensor low energy electron diffraction analysis SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID MGO(001) SURFACE; LEED; MGO; MONOLAYERS; INSITU; CHARGE; RHEED AB We present a low energy electron diffraction study of the surface relaxation of MgO(100) at T = 80 K down to the second atomic layer using in situ cleaved MgO crystals. We find that the main perturbation from the bulk structure is a topmost surface layer rumpling of 3.3 +/- 1.5% and a very small second layer rumpling of 0.2 +/- 2%. In both cases the oxygen atom is displaced outward. The first interlayer spacing is slightly reduced by 0.2 +/- 0.7% whereas there is no change in the second interlayer spacing. (C) 1998 American Vacuum Society. [S0734-2101(98)02104-6]. C1 Fac Sci Luminy, Dept Phys, CNRS, CRMC2, F-13288 Marseille 9, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Suzanne, J (reprint author), Fac Sci Luminy, Dept Phys, CNRS, CRMC2, F-13288 Marseille 9, France. RI Van Hove, Michel/A-9862-2008; Ferry, Daniel/O-2664-2014 OI Van Hove, Michel/0000-0002-8898-6921; Ferry, Daniel/0000-0003-1469-9871 NR 27 TC 13 Z9 13 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2261 EP 2266 DI 10.1116/1.581337 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700038 ER PT J AU Li, DQ Keavney, DJ Pearson, J Jiang, JS Bader, SD Keune, W AF Li, DQ Keavney, DJ Pearson, J Jiang, JS Bader, SD Keune, W TI Growth and characterization of epitaxial fcc Fe wedges on diamond (100) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 44th National Symposium of the American-Vacuum-Society CY OCT 20-24, 1997 CL SAN JOSE, CALIFORNIA SP Amer Vacuum Soc ID MAGNETIC PHASES; FILMS; TEMPERATURE; FE/CU(100); FE(100); CU(100); LAYERS; IRON AB Epitaxial Fe wedges with a thickness gradation from 0 to 20 Angstrom were grown on diamond (100) at room temperature, subsequently annealed, and investigated with reflection high-energy electron diffraction and the surface magneto-optical Kerr effect. The results indicate that for <5 monolayer thicknesses the Fe grows on C(100) as smooth, epitaxial fee films, which are not ferromagnetic, but that thicker films undergo a transition to become rough and the ordinary bcc ferromagnetic phase. (C) 1998 American Vacuum Society. [S0734-2101(98)09104-0]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Gerhard Mercator Univ, Lab Angew Phys, D-47048 Duisburg, Germany. RP Li, DQ (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Bader, Samuel/A-2995-2013 NR 23 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 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2326 EP 2329 DI 10.1116/1.581347 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700049 ER PT J AU Levinson, JA Hamza, AV Shaqfeh, ESG Balooch, M AF Levinson, JA Hamza, AV Shaqfeh, ESG Balooch, M TI Growth of SiC films via C-60 precursors and a model for the profile development of the silicon underlayer SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; CHEMICAL VAPOR-DEPOSITION; VARIABLE-TEMPERATURE STM; SURFACE-DIFFUSION; MOLECULAR-DYNAMICS; CARBIDE FILMS; ADSORPTION; SIMULATION; SI(111)-(7X7); SI(100)-(2X1) AB We report on an experimental and theoretical study of the growth of SiC films and of the profile development of the silicon underlayer. SIC features were grown via the direct reaction of the silicon substrate with C-60 precursors. Two masking configurations were used to investigate the effects of bulk and surface diffusion on SiC film growth. Without a diffusion barrier (i.e., a patterned SiO2 mask with regions of silicon initially exposed directly to C60) voids formed in the substrate beneath the growing SiC layer, which ultimately controlled the final thickness of the SiC film. Pronounced faceting was observed at the early stages of growth on crystalline silicon. When a tungsten diffusion barrier was used to prevent bulk diffusion (i.e., tungsten covering silicon in non-SiO2 masked regions), significant undercutting resulted beneath the oxide and SiC layers without void formation. A profile simulation was developed to model the time evolution of the silicon underlayer when this diffusion barrier is used. The simulation incorporated an adatom hopping and surface diffusion model to describe the generation and transport of silicon atoms along the evolving profile. A single fitting parameter was required. The agreement between simulation and experiment was good, and a corresponding value of the hopping coefficient was calculated. As an alternative to direct reaction with the silicon substrate, we also demonstrate experimentally that silicon atoms can be co-sublimed with fullerenes to produce SiC films on wafer surfaces, which avoids the consumption of substrate material. Co-sublimation was used to create SiC membranes and also to coat silicon microcantilevers. Force-deflection measurements for the microcantilevers revealed that the stiffness properties were enhanced with the application of a SIC film and that the co-sublimed SiC had mechanical properties like those of bulk material. (C) 1998 American Vacuum Society. [S0734-2101(98)08404-8]. C1 Stanford Univ, Dept Chem Engn, Stanford, CA 94305 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Levinson, JA (reprint author), Stanford Univ, Dept Chem Engn, Stanford, CA 94305 USA. NR 37 TC 7 Z9 8 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2385 EP 2394 DI 10.1116/1.581357 PG 10 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700059 ER PT J AU Proskurovsky, DI Rotshtein, VP Ozur, GE Markov, AB Nazarov, DS Shulov, VA Ivanov, YF Buchheit, RG AF Proskurovsky, DI Rotshtein, VP Ozur, GE Markov, AB Nazarov, DS Shulov, VA Ivanov, YF Buchheit, RG TI Pulsed electron-beam technology for surface modification of metallic materials SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID ION-BEAMS; INTENSE AB This article concerns the foundations of a new technology for surface modification of metallic materials based on the use of original sources of low-energy, high-current electron beams. The sources contain an electron gun with an explosive-emission cathode and a plasma anode, placed in a guide magnetic field. The acceleration gap and the transportation channel are prefilled with plasma with the use of spark plasma sources or a low-pressure reflected discharge. The electron-beam sources produce electron beams with the parameters as follows: electron energy 10-40 keV; pulse duration 0.5-5 mu s; energy density 0.5-40 J/cm(2), and beam cross-section area 10-50 cm(2). They are simple and reliable in operation. Investigations performed with a variety of constructional and tool materials (steels, aluminum and titanium alloys, hard alloys) have shown that the most pronounced changes of the structure-phase state occur in the near-surface layers quenched from the liquid state, where the crystallization front velocity reaches its maximum. In these layers partial or complete dissolving of second phases and formation of oversaturated solid solutions and ordered nanosized structures may take place. This makes it possible to improve substantially the electrochemical and strength properties of the surface layers. It has been established that the deformation processes occurring in the near-surface layers have the result that the thickness of the modified layer with improved strength properties is significantly greater than that of the heat-affected zone. Some examples of the use of low-energy, high-current electron beams for improving the performance of materials and articles are given. (C) 1998 American Vacuum Society. [S0734-2101(98)03604-5]. C1 Russian Acad Sci, Inst High Current Elect, Tomsk 634055, Russia. Moscow Aviat Inst, Moscow 125871, Russia. State Univ Architecture & Bldg, Tomsk 634003, Russia. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Proskurovsky, DI (reprint author), Russian Acad Sci, Inst High Current Elect, 4 Academichesky, Tomsk 634055, Russia. RI Ivanov, Yurii/A-9268-2014; Ozur, Grigory/E-5992-2017 OI Ivanov, Yurii/0000-0001-8022-7958; Ozur, Grigory/0000-0003-3899-9246 NR 32 TC 174 Z9 219 U1 0 U2 34 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2480 EP 2488 DI 10.1116/1.581369 PG 9 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700072 ER PT J AU Chen, CL Jia, QX Lu, YC Smith, JL Mitchell, TE AF Chen, CL Jia, QX Lu, YC Smith, JL Mitchell, TE TI Heteroepitaxial growth of RuO2 thin films on alpha-Al2O3 substrates with CeO2 buffer layers by pulsed laser deposition SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID FATIGUE AB Metallic conductive ruthenium oxide thin films have been grown epitaxially on sapphire (01 (1) over bar 2) with a cerium oxide buffer layer by pulsed laser deposition. We used transmission electron microscopy, high-resolution electron microscopy, and x-ray diffraction to characterize the growth behavior of the films and the orientation relationship between the films and the substrate. Our electron diffraction and x-ray diffraction studies indicate that the orientation relationships are (200)(RuO2)//(200)(CeO2)//(01 (1) over bar 2)(Al2O3) and [011](RuO2)//[001](CeO2)//[2 (2) over bar 01](Al2O3). All Of the interfaces were seen to be atomically sharp by cross-sectional, high-resolution transmission electron microscopy in the as-grown samples. No precipitates or additional phases were found in the films or at their interfaces. (C) 1998 American Vacuum Society. [S0734-2101(98)05904-1]. C1 Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Chen, CL (reprint author), Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. RI Jia, Q. X./C-5194-2008 NR 10 TC 1 Z9 1 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1998 VL 16 IS 4 BP 2725 EP 2727 DI 10.1116/1.581407 PG 3 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 101CU UT WOS:000074852700112 ER PT J AU Suh, BJ Hammel, PC Zhang, Z Midzor, MM Roukes, ML Childress, JR AF Suh, BJ Hammel, PC Zhang, Z Midzor, MM Roukes, ML Childress, JR TI Ferromagnetic resonance imaging of Co films using magnetic resonance force microscopy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 25th Annual Conference on the Physics and Chemistry of Semiconductor Interfaces CY JAN 18-22, 1998 CL SALT LAKE CITY, UTAH ID ELECTRON-SPIN-RESONANCE AB Lateral one-dimensional imaging of cobalt (Co) films by means of microscopic ferromagnetic resonance (FMR) detected using the magnetic resonance force microscope (MRFM) is demonstrated. A novel approach involving scanning a localized magnetic probe is shown to enable FMR imaging in spite of the broad resonance linewidth. We introduce a spatially selective local field by means of a small, magnetically polarized spherical crystallite of yttrium iron garnet (YIG). Using MRFM-detected FMR signals from a sample consisting of two Co films, we can resolve the similar to 20 mu m lateral separation between the films. The results can be qualitatively understood by consideration of the calculated spatial profiles of the magnetic field generated by the YIG sphere. (C) 1998 American Vacuum Society. 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, 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 15 TC 15 Z9 15 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 1998 VL 16 IS 4 BP 2275 EP 2279 DI 10.1116/1.590161 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 110LN UT WOS:000075381400087 ER PT J AU Garrott, RA Cook, JG Bernoco, MM Kirkpatrick, JF Cadwell, LL Cherry, S Tiller, B AF Garrott, RA Cook, JG Bernoco, MM Kirkpatrick, JF Cadwell, LL Cherry, S Tiller, B TI Antibody response of elk immunized with porcine zona pellucida SO JOURNAL OF WILDLIFE DISEASES LA English DT Article DE adjuvants; Cervus elaphus; contraception; fertility control; immunocontraception; porcine zona pellucida antibody; reproduction; Rocky Mountain elk; vaccine ID WHITE-TAILED DEER; REMOTELY-DELIVERED IMMUNOCONTRACEPTION; OVARIAN-FUNCTION; FERAL HORSES; CONTRACEPTION; STREPTAVIDIN; MARES; SERUM AB Immunocontraception using porcine zona pellucida (PZP) vaccines is being explored as a nonlethal method of solving the problems of locally overabundant wildlife populations. This study characterized the immunological response of captive elk (Cervus elaphus nelsoni) to PZP challenge using 18 3-yr-old cows and was conducted from 14 September 1994 to 13 December 1995. All animals were given a single PZP inoculation and 1 mo later six of these animals were randomly chosen and received a booster inoculation. Blood samples were drawn from all animals at the time of the initial inoculation and 1, 2, 4, 6, 10, and 15 mo later. Immunological response was assessed by measuring anti-PZP antibody levels in serum. All animals demonstrated a strong immune response with no evidence that the booster enhanced antibody levels. Antibody levels rose from between 0 and 4 at the time of the initial injection to peak levels of 85 to 163 within 2 to 6 mo, followed by a noticeable decline by 15 mo post-vaccination, Limited data suggest that antibody levels >100 may be required to effect contraception. High individual variability in immune response observed in this study suggests it may be difficult to predict the proportion of animals effectively treated. Disruption of seasonal synchrony in calving also could occur if antibody levels in individuals fall below effective levels while animals are still cycling. These results indicate that immunocontraception using PZP vaccines is possible for elk. However, carefully controlled population experiments will be required in order to assess the potential and limitations for management applications of this technique. C1 Montana State Univ, Dept Biol, Fish & Wildlife Management Program, Bozeman, MT 59717 USA. Natl Council Paper Ind Air & Stream Improvement In, Forestry & Range Sci Lab, La Grande, OR 97850 USA. Univ Calif Davis, Dept Populat Hlth & Reprod, Davis, CA 95616 USA. ZooMontana, Billings, MT 59108 USA. Pacific NW Lab, Richland, WA 99352 USA. Montana State Univ, Dept Math Sci, Bozeman, MT 59717 USA. RP Garrott, RA (reprint author), Montana State Univ, Dept Biol, Fish & Wildlife Management Program, 310 Lewis Hall, Bozeman, MT 59717 USA. EM ubirg@montana.edu NR 30 TC 24 Z9 24 U1 0 U2 0 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 USA SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD JUL PY 1998 VL 34 IS 3 BP 539 EP 546 PG 8 WC Veterinary Sciences SC Veterinary Sciences GA 107EH UT WOS:000075193700014 PM 9706563 ER PT J AU Birtcher, RC Donnelly, SE AF Birtcher, RC Donnelly, SE TI Plastic flow in FCC metals induced by single-ion impacts SO MATERIALS CHEMISTRY AND PHYSICS LA English DT Article; Proceedings Paper CT 4th IUMRS International Conference CY SEP 16-18, 1997 CL OVERSEAS VOCAT TRAINING ASSOC, CHIBA, JAPAN HO OVERSEAS VOCAT TRAINING ASSOC DE plastic flow; FCC metals; single-ion impacts ID IRRADIATION; GOLD AB Irradiation of Au and ph foils with Xe ions at temperatures between 30 and 450 K has been monitored using in situ transmission electron microscopy. Single ion impacts give rise to surface craters on the irradiated surface with sizes as large as 12 nm. Approximately 2%-5% of impinging ions produce craters on Au while only about 0.6% produce craters on Pb. Larger craters on Au frequently have expelled material associated with them. Temporal details of crater formation and annihilation has been recorded on video with a time-resolution of 33 ms. Craters annihilate in discrete steps due to subsequent ion impacts or anneal in a continuous manner due to surface diffusion. Craters production (those persisting for one or more video-frames) as a function of temperature indicates that the surface diffusion process responsible for thermal annealing of craters has an activation energy of 0.76 eV in Au. Crater creation results from plastic flaw associated with near surface cascades. Crater annihilation in discrete steps results from plastic flow induced by subsequent ion impacts, including those that do not themselves produce a crater. Crown Copyright (C) 1998 Published by Elsevier Science S.A. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Salford, Joule Phys Lab, Sci Res Inst, Salford M5 4WT, Lancs, England. RP Birtcher, RC (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Donnelly, Stephen/0000-0002-9749-5550 NR 10 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0254-0584 J9 MATER CHEM PHYS JI Mater. Chem. Phys. PD JUL PY 1998 VL 54 IS 1-3 BP 111 EP 115 DI 10.1016/S0254-0584(98)00019-4 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA ZY880 UT WOS:000074671500021 ER PT J AU Davis, HA Wood, BP Munson, CP Bitteker, LJ Nastasi, MA Rej, DJ Waganaar, WJ Walter, KC Coates, DM Schleinitz, HM AF Davis, HA Wood, BP Munson, CP Bitteker, LJ Nastasi, MA Rej, DJ Waganaar, WJ Walter, KC Coates, DM Schleinitz, HM TI Ion beam and plasma technology development for surface modification at Los Alamos National Laboratory SO MATERIALS CHEMISTRY AND PHYSICS LA English DT Article; Proceedings Paper CT 4th IUMRS International Conference CY SEP 16-18, 1997 CL OVERSEAS VOCAT TRAINING ASSOC, CHIBA, JAPAN HO OVERSEAS VOCAT TRAINING ASSOC DE plasma; implantation; ion beams; ions; coatings; surface treatment ID IMPLANTATION AB We are developing two high-throughput technologies for materials modification. The first is a repetitive intense ion beam source for materials modification through rapid surface melt and resolidification (up to 10(10) K s(-1) cooling rates) and for ablative deposition of coatings. The short range of the ions (typically 0.1 to 10 mu m) allows vaporization or melting at moderate beam energy density (typically 1-50 J cm(-2)).A new repetitive intense ion beam accelerator called CHAMP is under development at Los Alamos. The design beam parameters are: E= 200-250 keV, I= 15 kA, tau=1 mu s, and I Hz. This accelerator will enable applications such as film deposition, alloying and mixing, cleaning and polishing, corrosion and wear resistance, polymer surface treatments, and nanophase powder synthesis. The second technology is plasma source ion implantation (PSII) using plasmas generated from both gas phase (using radio frequency excitation) and solid phase (using a cathodic are) sources. We have used PSII to directly implant ions for surface modification and as a method for generating graded interfaces to enhance the adhesion of surface coatings. Surfaces with areas of up to 16 m(2) and weighing more than a thousand kilograms have been treated in the Los Alamos PSII chamber. In addition, PSII in combination with cathodic source deposition has been used to form highly adherent, thick Er2O3 coatings on steel for reactive metal containment in casting. These coatings resist delamination under extreme mechanical and thermal stress. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Dupont Co, Cent Res & Dev, Wilmington, DE 19880 USA. RP Davis, HA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 12 TC 24 Z9 27 U1 2 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0254-0584 J9 MATER CHEM PHYS JI Mater. Chem. Phys. PD JUL PY 1998 VL 54 IS 1-3 BP 213 EP 218 DI 10.1016/S0254-0584(98)00102-3 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA ZY880 UT WOS:000074671500043 ER PT J AU Holcomb, GR Cryer, CB AF Holcomb, GR Cryer, CB TI Cost of impressed current cathodic protection for coastal Oregon bridges SO MATERIALS PERFORMANCE LA English DT Article AB The State of Oregon is using arc-sprayed zinc coatings to serve as anodes in impressed current cathodic protection (CP) systems on corrosion-damaged portions of reinforced concrete coastal bridges. Total project costs are detailed, including zinc coating anode application and other CP materials and installation. Repair procedures are described. C1 US Dept Energy, Albany Res Ctr, Albany, OR 97321 USA. Oregon Dept Transportat, Bridge Sect, Salem, OR 97310 USA. RP Holcomb, GR (reprint author), US Dept Energy, Albany Res Ctr, Albany, OR 97321 USA. RI Holcomb, Gordon/G-9070-2013 OI Holcomb, Gordon/0000-0003-3542-5319 NR 6 TC 4 Z9 4 U1 1 U2 3 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0094-1492 J9 MATER PERFORMANCE JI Mater. Perform. PD JUL PY 1998 VL 37 IS 7 BP 22 EP 26 PG 5 WC Materials Science, Characterization & Testing SC Materials Science GA ZZ398 UT WOS:000074725400006 ER PT J AU Kloc, M Larabell, C Chan, APY Etkin, LD AF Kloc, M Larabell, C Chan, APY Etkin, LD TI Contribution of METRO pathway localized molecules to the organization of the germ cell lineage SO MECHANISMS OF DEVELOPMENT LA English DT Article DE development; oogenesis; RNA localization; Xenopus laevis; germ plasm ID BOX TRANSCRIPTION FACTOR; MATERNAL MESSENGER-RNA; XENOPUS-OOCYTES; DROSOPHILA OOGENESIS; VEGETAL CORTEX; ENDOPLASMIC-RETICULUM; MESODERM FORMATION; STEM-CELLS; PLASM; EMBRYOS AB To elucidate the potential role of localized components in the specification of the germ cell lineage we analyzed the composition of the germ plasm in Xenopus laevis oocytes and early embryos with respect to the vegetally-localized RNAs. We focused on Xlsirts, Xcat2, and Xwnt11 transcripts that are localized to the vegetal cortex through a region of the mitochondrial cloud called the messenger transport organizer (METRO) that also contains the nuage or germ plasm. At the ultrastructural level Xcat2 mRNA was detected on germinal granules while Xlsirts and Xwnt11 were associated with a fibrillar network of the germ plasm in stage-1 and stage-4 oocytes. In embryos, we found that all three RNAs remained associated with the germ plasm. Vg1 mRNA, a transcript localized through the late pathway, was excluded from the germ plasm in oocytes and embryos. Addtionally, we detected the protein spectrin within 16 cell nests of germ cells, in a structure reminiscent of the Drosophila spectrosome. Spectrin was detected in the mitochondrial cloud and was found in the germ plasm during embryogrenesis. These data indicate that the various RNAs found within METRO and the protein spectrin are integral components of the Xenopus germ plasm with the RNAs being associated with different subcellular structures. They also suggest that the pathway through which RNAs are localized during oogenesis may be an important factor in biasing their distribution into specific cell lineages. The presence of Xwnt11 in the germ cell lineage suggests that a wnt-directed signaling pathway may be involved in germ cell specification, differentiation or migration. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 Univ Texas, MD Anderson Canc Ctr, Dept Mol Genet, Houston, TX 77030 USA. Univ Calif Berkeley, Lawrence Berkeley Labs, Berkeley, CA 94720 USA. RP Etkin, LD (reprint author), Univ Texas, MD Anderson Canc Ctr, Dept Mol Genet, 1515 Holcombe Blvd, Houston, TX 77030 USA. EM lde@mdacc.tmc.edu FU NCI NIH HHS [CA 16672] NR 75 TC 66 Z9 67 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0925-4773 J9 MECH DEVELOP JI Mech. Dev. PD JUL PY 1998 VL 75 IS 1-2 BP 81 EP 93 DI 10.1016/S0925-4773(98)00086-0 PG 13 WC Developmental Biology SC Developmental Biology GA 121PX UT WOS:000076023500006 PM 9739112 ER PT J AU Turchi, PEA Schwarz, RB Perepezko, JH AF Turchi, PEA Schwarz, RB Perepezko, JH TI Symposium on Structure and Properties of Bulk Amorphous Alloys - Foreword SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Editorial Material C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Univ Wisconsin, Madison, WI 53706 USA. RP Turchi, PEA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 JUL PY 1998 VL 29 IS 7 BP 1775 EP 1776 PG 2 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 104BJ UT WOS:000074992100001 ER PT J AU Gottschall, RJ AF Gottschall, RJ TI Structure and properties of bulk amorphous alloys - Foreword address SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Editorial Material ID GLASSES C1 US DOE, Off Basic Energy Sci, Div Sci Mat, Germantown, MD 20874 USA. RP Gottschall, RJ (reprint author), US DOE, Off Basic Energy Sci, Div Sci Mat, Germantown, MD 20874 USA. NR 13 TC 4 Z9 4 U1 2 U2 2 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 JUL PY 1998 VL 29 IS 7 BP 1777 EP 1778 PG 2 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 104BJ UT WOS:000074992100002 ER PT J AU He, Y Shen, TD Schwarz, RB AF He, Y Shen, TD Schwarz, RB TI Bulk amorphous metallic alloys: Synthesis by fluxing techniques and properties SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Structure and Properties of Bulk Amorphous Alloys Symposium at the 1997 Annual Meeting of TMS CY FEB 10-11, 1997 CL ORLANDO, FL SP TMS-EMPMD/SMD Alloy Phases & MDMD Solidificat Comm, ASM-MSD Thermodynam & Phase Equilibria, Atom Transport Comm ID GLASS-TRANSITION TEMPERATURE; MOLD CASTING METHOD; UNDERCOOLED MELTS; CRYSTAL-GROWTH; ELASTIC-MODULI; HEAT-CAPACITY; NI; LIQUID; PD; SOLIDIFICATION AB Bulk amorphous alloys having dimensions of at least 1 cm in diameter have been prepared in the Pd-Ni-P, Pd-Cu-P, Pd-Cu-Ni-P, and Pd-Ni-Fe-P systems using a fluxing and water-quenching technique. The compositions for bulk glass formation have been determined in these systems. For these bulk metallic glasses, the difference between the crystallization temperature (T-x) and the glass transition temperature (T-g, Delta T = T-x - T-g) ranges from 60 to 110 K. These large values of Delta T open the possibility for the fabrication of amorphous near-net-shaped components using techniques such as injection molding. The thermal, elastic, and magnetic properties of these alloys have been studied, and we have found that bulk amorphous Pd40Ni22.5Fe17.5P20 has spin glass behavior for temperatures below 30 K. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP He, Y (reprint author), Intel Corp, Chandler, AZ 85226 USA. NR 61 TC 50 Z9 51 U1 2 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 JUL PY 1998 VL 29 IS 7 BP 1795 EP 1804 DI 10.1007/s11661-998-0002-8 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 104BJ UT WOS:000074992100004 ER PT J AU Egami, T Dmowski, W He, Y Schwarz, RB AF Egami, T Dmowski, W He, Y Schwarz, RB TI Structure of bulk amorphous Pd-Ni-P alloys determined by synchrotron radiation SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Structure and Properties of Bulk Amorphous Alloys Symposium at the 1997 Annual Meeting of TMS CY FEB 10-11, 1997 CL ORLANDO, FL SP TMS-EMPMD/SMD Alloy Phases & MDMD Solidificat Comm, ASM-MSD Thermodynam & Phase Equilibria, Atom Transport Comm ID X-RAY-SCATTERING; GLASS-FORMATION; METALLIC-GLASS; TEMPERATURE AB The atomic structure of Pd-Ni-P bulk amorphous alloys was studied by the anomalous (resonance) X-ray scattering technique using synchrotron radiation tuned near the Pd K-edge. Bulk samples of Pd(40)Ni(40)P(20), Pd(30)Ni(50)P(20), and Pd(50)Ni(34)P(16) amorphous alloys were prepared by the flux method in the form of rods. The results show that the structure of these alloys can be described basically by the dense random packed structure with small chemical short-range order. It is suggested that the exceptional stability of these glasses originates mainly from the instability of the competing crystalline phases rather than the atomic ordering in these glasses. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Egami, T (reprint author), Univ Penn, Dept Mat Sci & Engn, 3231 Walnut St, Philadelphia, PA 19104 USA. NR 20 TC 31 Z9 32 U1 1 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JUL PY 1998 VL 29 IS 7 BP 1805 EP 1809 DI 10.1007/s11661-998-0003-7 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 104BJ UT WOS:000074992100005 ER PT J AU Liu, CT Heatherly, L Easton, DS Carmichael, CA Schneibel, JH Chen, CH Wright, JL Yoo, MH Horton, JA Inoue, A AF Liu, CT Heatherly, L Easton, DS Carmichael, CA Schneibel, JH Chen, CH Wright, JL Yoo, MH Horton, JA Inoue, A TI Test environments and mechanical properties of Zr-base bulk amorphous alloys SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Structure and Properties of Bulk Amorphous Alloys Symposium at the 1997 Annual Meeting of TMS CY FEB 10-11, 1997 CL ORLANDO, FLORIDA SP TMS-EMPMD/SMD Alloy Phases & MDMD Solidificat Comm, ASM-MSD Thermodynam & Phase Equilibria, Atom Transport Comm ID SUPERCOOLED LIQUID REGION; METALLIC GLASSES; TEMPERATURE EMBRITTLEMENT; NI; FRACTURE; FE; STABILITY; BEHAVIOR; FLOW; CO AB The mechanical properties of two Zr-base bulk amorphous alloys (BAA), Zr-1oAl-30Cu-5Ni (BAA-10) and Zr-10Al-5Ti-17.9Cu-14.6Ni (BAA-11), were studied by both tensile and compressive tests at room temperature in various test environments. The BAA ingots up to 7 mm in diameter were successfully produced by both are melting and drop casting and induction melting and injection casting. The BAA specimens deformed mainly elastically, followed by catastrophic failure along shear bands. Examination of the fracture region revealed ductile fracture features resulting from a substantial increase in temperature, which was attributable to the conversion of the stored elastic strain energy to heat. Surprisingly, "liquid droplets" located at major shear-band cracks adjacent to the fracture section were observed, indicating the occurrence of local melting during fracture. The angle orientation of shear bands, shear-band cracks, and fracture surfaces relative to the stress axis is quite different for BAA specimens tested in tension and compression. This suggests that both shear stress and normal stress may play a role in developing shear bands during plastic deformation. The tensile properties of BAAs were found to be insensitive to the test environment at room temperature. However, the reaction of BAAs with distilled water and heavy water was detected by laser desorption mass spectrometry (LDMS). These results suggest that moisture-induced hydrogen embrittlement in BAAs may be masked by catastrophic fracture following shear bands. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan. RP Liu, CT (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Inoue, Akihisa/E-5271-2015; OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 35 TC 435 Z9 468 U1 10 U2 105 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 JUL PY 1998 VL 29 IS 7 BP 1811 EP 1820 DI 10.1007/s11661-998-0004-6 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 104BJ UT WOS:000074992100006 ER PT J AU Nicholson, DMC Stocks, GM Shelton, WA Wang, Y Swihart, JC AF Nicholson, DMC Stocks, GM Shelton, WA Wang, Y Swihart, JC TI Ab initio studies of the electronic structure and energetics of bulk amorphous metals SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Structure and Properties of Bulk Amorphous Alloys Symposium at the 1997 Annual Meeting of TMS CY FEB 10-11, 1997 CL ORLANDO, FLORIDA SP TMS-EMPMD/SMD Alloy Phases & MDMD Solidificat Comm, ASM-MSD Thermodynam & Phase Equilibria, Atom Transport Comm ID COPPER MOLD; X-RAY; ALLOYS; GLASSES; ORDER; CRYSTALLIZATION; TEMPERATURE; ENERGY AB Bulk amorphous metals (BAMs) are an interesting class of new materials possessing unique properties that offer exciting possibilities for applications to a broad range of technologies. In contrast to the previous generation of amorphous metals, BAMs can be produced in bulk form at cooling rates as low as similar to 1 K/s. The understanding of the structure, properties, and required cooling rates for BAM formation is hindered by the large number of constituents in typical alloys. In this article, we present the results of first principles local density approximation studies of the electronic structure and energetics of model Ni-Pd-P, Zr-Ni-Cu, and Zr-Ni-Al amorphous alloys that relate to two of the simplest BAMs, namely, Ni0.4Pd0.4P0.2 and Zr0.6Al0.15Ni0.25. The calculations are based on large unit cell (similar to 300-atom) structural models for which the electronic structure is calculated using the first principles order-N locally self-consistent multiple scattering method. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Pittsburgh Super Comp Ctr, Pittsburgh, PA 15213 USA. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. RP Nicholson, DMC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Stocks, George Malcollm/Q-1251-2016 OI Stocks, George Malcollm/0000-0002-9013-260X NR 30 TC 12 Z9 12 U1 0 U2 4 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 JUL PY 1998 VL 29 IS 7 BP 1845 EP 1851 DI 10.1007/s11661-998-0009-1 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 104BJ UT WOS:000074992100011 ER PT J AU Pike, LM Liu, CT Chang, YA AF Pike, LM Liu, CT Chang, YA TI Effect of Ni on vacancy concentrations and hardness in FeAl alloys SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID EMBRITTLEMENT; ADDITIONS AB The effects of nickel additions to iron aluminides are investigated with respect to vacancy concentrations and solid-solution hardening. Lattice parameters, densities, vacancy concentrations, and hardnesses were measured for FeAl alloys (40, 45, 48, 50, and 51 at. pct Al) with up to 12 at. pct Ni additions, as quenched at both 700 degrees C and 1000 degrees C. It is found that Ni does not prevent the elimination of thermal vacancies, as has been suggested in previous studies. However, the equilibrium vacancy concentrations are affected by the Ni additions. No clear evidence of solid-solution hardening by the Ni additions themselves was found. Instead, it appears that the role of Ni in hardening FeAl is through the effect the Ni has on the vacancy concentration. It was found that the hardness of most of the Ni-containing FeAl alloys could be directly correlated to the square root of the vacancy concentration. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. RP Pike, LM (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 23 TC 14 Z9 15 U1 0 U2 1 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 JUL PY 1998 VL 29 IS 7 BP 1911 EP 1915 DI 10.1007/s11661-998-0015-3 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 104BJ UT WOS:000074992100017 ER PT J AU Treiman, AH Romanek, CS AF Treiman, AH Romanek, CS TI Bulk and stable isotopic compositions of carbonate minerals in Martian meteorite Allan Hills 84001: No proof of high formation temperature SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID SYSTEM CACO3-MGCO3-FECO3; DIAGENETIC SIDERITE; AQUEOUS ALTERATION; SNC METEORITES; ALH84001; DOLOMITE; CHEMISTRY; CALCITE; MARS; CONCRETIONS AB Understanding the origin of carbonate minerals in the Martian meteorite Allan Hills (ALH) 84001 is crucial to evaluating the hypothesis that they contain traces of ancient Martian life. Using arguments based on chemical equilibria among carbonates and fluids, an origin at >650 degrees C (inimical to life) has been proposed. However, the bulk and stable isotopic compositions of the carbonate minerals are open to multiple interpretations and so lend no particular support to a high-temperature origin. Other methods (possibly less direct) will have to be used to determine the formation temperature of the carbonates in ALH 84001. C1 Lunar & Planetary Inst, Houston, TX 77058 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Treiman, AH (reprint author), Lunar & Planetary Inst, 3600 Bay Area Blvd, Houston, TX 77058 USA. NR 41 TC 39 Z9 39 U1 0 U2 4 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 BP 737 EP 742 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 114GV UT WOS:000075601500019 PM 11543073 ER PT J AU Romanek, CS Perry, EC Treiman, AH Socki, RA Jones, JH Gibson, EK AF Romanek, CS Perry, EC Treiman, AH Socki, RA Jones, JH Gibson, EK TI Oxygen isotopic record of silicate alteration in the Shergotty-Nakhla-Chassigny meteorite Lafayette SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID MARS VOLATILE EVOLUTION; SNC METEORITES; AQUEOUS ALTERATION; MARTIAN VOLATILES; STABLE ISOTOPES; ALH84001; CARBONATE; ORIGIN; TEMPERATURE; EETA-79001 AB Samples from a suite of Shergotty-Nakhla-Chassigny (SNC) meteorites were analyzed for their O isotopic ratios by a modified version of the laser fluorination technique. Measured isotopic ratios (O-17/O-16 and O-18/O-16) from bulk samples of the Shergottites, EETA79001, Shergotty and Zagami; the Nakhlite Lafayette; and Chassigny are similar to those reported in the literature, as are those from olivine and pyroxene mineral separates from Lafayette. Iddingsite, a preterrestrial alteration product of Lafayette, was measured for the first time as a separate phase. Oxygen isotopic ratios increase with the percentage of iddingsite in a sample to a maximum delta(18)O of 14.4 parts per thousand for a similar to 90% separate. Based on these measurements, end-member iddingsite has a delta(18)O of 15.6 parts per thousand, which places it among other O-18-enriched secondary phases (carbonate and silica) observed in SNC meteorites. The relatively large difference in delta(18)O between iddingsite and the olivine and pyroxene it replaces (similar to 11 parts per thousand) is typical of low-temperature alteration products. A range of crustal fluid delta(18)O values can be interpreted from the delta(18)O for end-member iddingsite, assuming isotopic equilibrium was achieved during low-temperature hydrous alteration (<100 degrees C; Treiman et al., 1993). The calculated range of values, -15 to 5 parts per thousand, depends on many factors including: (1) the modal mineralogy of iddingsite, (2) potential isotopic exchange among other O-bearing phases such as host silicate and carbonate, and (3) exchange with evolved or exotic O reservoirs on Mars. Despite the lack of constraints, the calculated range is consistent with isotopic exchange, and possibly equilibria, among components of the CO2-carbonate-iddingsite-H2O system at low temperature. The SNC meteorite samples in this study have Delta(17)O values that are indistinguishable from bulk Mars (0.30 parts per thousand), except for a single, small sample of iddingsite that has an anomalous Delta(17)O of similar to 1.4 parts per thousand. While analytical difficulties make isotopic measurements for this sample problematic, the Delta(17)O is similar in direction to Delta(17)O reported for waters extracted from bulk samples of Lafayette (Karlsson et al., 1992). If the Delta(17)O for iddingsite is confirmed, it can be concluded that evolved or exotic fluids on Mars have contributed volatiles to the O reservoir from which iddingsite formed 130 to 700 Ma ago. C1 Univ Georgia, Dept Geol, Aiken, SC 29802 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. No Illinois Univ, Dept Geol, De Kalb, IL 60115 USA. Lunar & Planetary Inst, Houston, TX 77058 USA. Lockheed Martin, Houston, TX 77058 USA. NASA, Johnson Space Ctr, Houston, TX 77058 USA. RP Univ Georgia, Dept Geol, Drawer E, Aiken, SC 29802 USA. EM romanek@srel.edu NR 76 TC 37 Z9 37 U1 1 U2 4 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1086-9379 EI 1945-5100 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 BP 775 EP 784 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 114GV UT WOS:000075601500023 ER PT J AU Fisler, DK Cygan, RT AF Fisler, DK Cygan, RT TI Cation diffusion in calcite: Determining closure temperatures and the thermal history for the Allan Hills 84001 meteorite SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID ALH84001; CARBONATE; EXCHANGE; SYSTEMS; ORIGIN; MARS AB The presence of zoned Fe, Mg, Ca, and Mn in the carbonate phases associated with the cracks and inclusions of the Allan Hills (ALH) 84001 meteorite provides evidence for constraining the thermal history of the meteorite. Using self- and tracer-diffusion coefficients obtained from laboratory experiments on natural calcite, cooling rates are calculated for various temperatures and diffusion distances to assist in the evaluation of the compositional zoning associated with the carbonate phases in ALH 84001. The closure temperature model provides the average temperature below which compositional zoning will be preserved for a given cooling rate, that is, the temperature at which diffusion will be ineffective in homogenizing the phase. The validity of various theories for the formation of the carbonate globules may be examined, therefore, in view of the diffusion-limited kinetic constraints. Experiments using a thin film-mineral diffusion couple and ion microprobe for depth profiling analysis were performed for the temperature range of 550-800 degrees C to determine self- and tracer-diffusion coefficients for Ca and Mg and in calcite. The resulting activation energies for Ca (E-a(Ca) = 271 +/- 80 kJ/mol) and for Mg (E-a(Mg) = 284 +/- 74 kJ/mol) were used then to calculate a series of cooling rate, grain size, and closure temperature curves. The data indicate, for example, that by the diffusion of Mg in calcite, a 10 mu m compositional zone would be completely homogenized at a temperature of 300 degrees C for cooling rates <100 K/Ma. These data provide no constraint on formation models that propose a low-temperature fluid precipitation mechanism; however, they indicate that the carbonate globules were not exposed to a high-temperature environment for long time scales following formation. C1 Sandia Natl Labs, Dept Geochem, Albuquerque, NM 87185 USA. RP Fisler, DK (reprint author), Sandia Natl Labs, Dept Geochem, Albuquerque, NM 87185 USA. FU NIDCR NIH HHS [DE-AC04-94AL85000] NR 24 TC 12 Z9 12 U1 0 U2 4 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 BP 785 EP 789 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 114GV UT WOS:000075601500024 PM 11543076 ER PT J AU Daulton, TL Lewis, RS Amari, S AF Daulton, TL Lewis, RS Amari, S TI Polytype variations in presolar silicon carbide grains: Microstructural characterization by transmission electron microscopy. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract ID MURCHISON METEORITE; SIC GRAINS C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Washington Univ, McDonnell Ctr Space Sci, St Louis, MO 63130 USA. NR 4 TC 4 Z9 5 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A37 EP A38 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000064 ER PT J AU Greenwood, JP Riciputi, LR Taylor, LA McSween, HY AF Greenwood, JP Riciputi, LR Taylor, LA McSween, HY TI Hydrothermal modification of sulfides in Nakhla, Lafayette, and Chassigny. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract ID SHERGOTTITES; METEORITES C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. NR 8 TC 2 Z9 2 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A62 EP A63 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000109 ER PT J AU Hutcheon, ID Krot, AN Keil, K Phinney, DL Scott, ERD AF Hutcheon, ID Krot, AN Keil, K Phinney, DL Scott, ERD TI Manganese-53/chromium-53 dating of fayalite in Mokoia: Evidence for asteroidal alteration of CV chondrites. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract C1 Univ Hawaii, Sch Ocean & Earth Sci & Technol, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A72 EP A73 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000129 ER PT J AU Jull, AJT Bland, PA Klandrud, S McHargue, LR Nishiizumi, K Caffee, MW AF Jull, AJT Bland, PA Klandrud, S McHargue, LR Nishiizumi, K Caffee, MW TI Cosmogenic radionuclide studies of desert meteorites, including a new lunar meteorite. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract ID TERRESTRIAL C1 Univ Arizona, Natl Sci Fdn, AMS Facil, Tucson, AZ 85721 USA. Open Univ, Milton Keynes MK7 6AA, Bucks, England. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A80 EP A80 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000142 ER PT J AU Lawrence, DJ Feldman, WC Binder, AB Maurice, S Barraclough, BL Elphic, RC AF Lawrence, DJ Feldman, WC Binder, AB Maurice, S Barraclough, BL Elphic, RC TI Mapping the elemental composition of the moon: Current results of the lunar prospector gamma-ray spectrometer SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract C1 Observ Midi Pyrenees, F-31400 Toulouse, France. Lunar Res Inst, Gilroy, CA 95020 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RI Lawrence, David/E-7463-2015 OI Lawrence, David/0000-0002-7696-6667 NR 3 TC 0 Z9 0 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A92 EP A92 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000166 ER PT J AU Nicolussi, GK Pellin, MJ Lewis, RS Davis, AM Clayton, RN Amari, S AF Nicolussi, GK Pellin, MJ Lewis, RS Davis, AM Clayton, RN Amari, S TI Strontium isotopes in single presolar silicon carbide grains. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract C1 Washington Univ, McDonnell Ctr Space Sci, St Louis, MO 63130 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. Univ Chicago, Dept Chem, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Argonne Natl Lab, Div Chem & Mat Sci, Argonne, IL 60439 USA. RI Pellin, Michael/B-5897-2008 OI Pellin, Michael/0000-0002-8149-9768 NR 8 TC 2 Z9 2 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A116 EP A117 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000209 ER PT J AU Nishiizumi, K Caffee, MW AF Nishiizumi, K Caffee, MW TI Measurements of cosmogenic calcium-41 and calcium-41/chlorine-36 terrestrial ages. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract ID EXPOSURE C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NR 3 TC 11 Z9 11 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A117 EP A117 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000210 ER PT J AU Reedy, RC AF Reedy, RC TI Variations in solar-proton fluxes over the last million years. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM rreedy@lanl.gov RI Lawrence, David/E-7463-2015 OI Lawrence, David/0000-0002-7696-6667 NR 6 TC 3 Z9 3 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A127 EP A127 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000231 ER PT J AU Reedy, RC Feldman, WC Barraclough, BL Binder, AB Elphic, RC Lawrence, DJ Maurice, S Masarik, J AF Reedy, RC Feldman, WC Barraclough, BL Binder, AB Elphic, RC Lawrence, DJ Maurice, S Masarik, J TI Fast neutrons from the moon: Measured and calculated fluxes. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract C1 Comenius Univ, Bratislava, Slovakia. Observ Midi Pyrenees, F-31400 Toulouse, France. Lunar Res Inst, Gilroy, CA 95020 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RI Lawrence, David/E-7463-2015 OI Lawrence, David/0000-0002-7696-6667 NR 5 TC 3 Z9 3 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A127 EP A128 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000232 ER PT J AU Sexton, AS Bland, PA Wolf, SF Franchi, IA Hough, RM Jull, AJT Klandrud, SE Berry, FJ Pillinger, CT AF Sexton, AS Bland, PA Wolf, SF Franchi, IA Hough, RM Jull, AJT Klandrud, SE Berry, FJ Pillinger, CT TI Anomalous chondrites from the Sahara. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract C1 Open Univ, Dept Chem, Milton Keynes MK7 6AA, Bucks, England. Univ Arizona, Arizona AMS Facil, Natl Sci Fdn, Tucson, AZ 85721 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Western Australian Museum, Perth, WA 6000, Australia. Open Univ, Planetary Sci Res Inst, Milton Keynes MK7 6AA, Bucks, England. NR 3 TC 1 Z9 1 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A143 EP A143 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000261 ER PT J AU Wacker, JF Hildebrand, AR Brown, P Crawford, D Boslough, M Chael, E Revelle, D Doser, D Tagliaferri, E Rathbun, D Cooke, D Adcock, C Karner, J AF Wacker, JF Hildebrand, AR Brown, P Crawford, D Boslough, M Chael, E Revelle, D Doser, D Tagliaferri, E Rathbun, D Cooke, D Adcock, C Karner, J TI The Juancheng and El Paso superbolides of February 15, 1997, and October 9, 1997: Preatmospheric meteoroid sizes. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract ID ROBERT C1 Pacific NW Lab, Richland, WA 99352 USA. Geol Survey Canada, Ottawa, ON, Canada. Univ Western Ontario, Dept Phys, London, ON N6A 3K7, Canada. Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, Los Alamos, NM USA. Univ Texas, Dept Geol Sci, El Paso, TX 79968 USA. El Paso Med Ctr, El Paso, TX 79902 USA. Univ Texas, Dept Comp Sci, El Paso, TX 79968 USA. Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. ET Space Syst, Camarilo, CA 93012 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A160 EP A161 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000293 ER PT J AU Welten, KC Nishiizumi, K Caffee, MW Wieler, R AF Welten, KC Nishiizumi, K Caffee, MW Wieler, R TI Terrestrial ages of H chondrites from Frontier Mountain, Antarctica. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract ID METEORITES C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. ETH Zurich, CH-8092 Zurich, Switzerland. NR 6 TC 0 Z9 0 U1 1 U2 1 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A166 EP A167 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000304 ER PT J AU Zito, KL McKeegan, KD Kerridge, JF Hutcheon, ID Leshin, LA AF Zito, KL McKeegan, KD Kerridge, JF Hutcheon, ID Leshin, LA TI Aqueous alteration on the CI parent-body evidence from oxygen- and carbon-isotopic studies of single carbonate grains from Orgueil. SO METEORITICS & PLANETARY SCIENCE LA English DT Meeting Abstract ID CHONDRITES; METEORITES C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. Univ Calif San Diego, Dept Chem, La Jolla, CA 92093 USA. Univ Calif Lawrence Livermore Natl Lab, Isotope Sci Div, Livermore, CA 94551 USA. RI McKeegan, Kevin/A-4107-2008 OI McKeegan, Kevin/0000-0002-1827-729X NR 9 TC 2 Z9 2 U1 0 U2 1 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 1998 VL 33 IS 4 SU S BP A171 EP A172 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 117JK UT WOS:000075778000313 ER PT J AU Gross, C Tobin, KW Jensen, D Mehta, D AF Gross, C Tobin, KW Jensen, D Mehta, D TI Assessing future technology requirements for rapid isolation and sourcing of faults SO MICRO LA English DT Editorial Material ID CLASSIFICATION C1 Intel Corp, Fab 17, Hudson, MA 01479 USA. Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, Oak Ridge, TN 37831 USA. SEMATECH, AMD, Austin, TX 78741 USA. Semicond Res Corp, Res Triangle Pk, NC USA. RP Gross, C (reprint author), Intel Corp, Fab 17, Hudson, MA 01479 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU CANON COMMUNICATIONS INC PI SANTA MONICA PA 3340 OCEAN PARK BLVD, SUITE 1000, SANTA MONICA, CA 90405 USA SN 1081-0595 J9 MICRO JI Micro PD JUL-AUG PY 1998 VL 16 IS 7 BP 57 EP + PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Science & Technology - Other Topics; Materials Science; Physics GA 147ZR UT WOS:000077528200040 ER PT J AU Chandler, DP Brockman, FJ Bailey, TJ Fredrickson, JK AF Chandler, DP Brockman, FJ Bailey, TJ Fredrickson, JK TI Phylogenetic diversity of archaea and bacteria in a deep subsurface paleosol SO MICROBIAL ECOLOGY LA English DT Article ID RIBOSOMAL-RNA SEQUENCES; LENGTH-POLYMORPHISM ANALYSIS; COMMUNITY STRUCTURE; UNCULTURED MICROORGANISMS; HETEROTROPHIC BACTERIA; MICROBIAL-POPULATIONS; INSITU HYBRIDIZATION; PROBE HYBRIDIZATION; SEDIMENTS; GENES AB A low-biomass paleosol 188 m below the ground surface at the Department of Energy's Hanford Site in south-central Washington State was recovered and maintained at the in situ temperature (17 degrees C) as an intact core or homogenized sediment for 0, 1, 3, 10, and 21 weeks post-sampling. Bacterial and archaeal 16S rRNA genes were amplified by PCR and cloned. Of 746 bacterial and 190 archaeal clones that were categorized by restriction fragment length polymorphism (RFLP), 242 bacterial and 16 archaeal clones were partially sequenced and compared against the small subunit ribosomal RNA database (RDP) and GenBank. Six bacterial and 16 archaeal clones sequences, with little similarity to those in public databases, were sequenced in their entirety, and subjected to more detained phylogenetic analysis. The most frequently occurring clones types were related to Pseudomonas, Bacillus, Micrococcus, Clavibacter, Nocardioides, Burkholderia, Comamonas, and Erythromicrobium. Clone sequences whose RDP similarity value was greater than or equal to 0.6 consistently grouped with their nearest RDP neighbor during phylogenetic analysis. Six truly novel eubacterial sequences were identified; they consistently cluster with or near the Chloroflexaceae and sequences recovered from the Sargasso Sea. Sixteen unique archaeal RFLP groups were identified from 190 randomly-sampled clones. The novel archaeal rDNA clones formed a coherent clade along the major Crenarchaea branch containing all previously described mesophilic crenarchae clones, but remained firmly associated with 16S rDNA clones previously obtained from a thermal Fe/S spring in Yellowstone National Park. The wealth of group-specific genetic information identified during this study will now allow us to address specific hypotheses related to in situ stimulation of these deep subsurface microorganisms and changes in microbial community composition resulting from subsurface contamination or remediation processes at the Hanford Site. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Chandler, DP (reprint author), Pacific NW Lab, 900 Battelle Blvd, Richland, WA 99352 USA. EM dp_chandler@pnl.gov NR 72 TC 91 Z9 98 U1 1 U2 12 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0095-3628 J9 MICROBIAL ECOL JI Microb. Ecol. PD JUL-AUG PY 1998 VL 36 IS 1 BP 37 EP 50 DI 10.1007/s002489900091 PG 14 WC Ecology; Marine & Freshwater Biology; Microbiology SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Microbiology GA ZU805 UT WOS:000074236700005 ER PT J AU Leganes, F Fernandez-Pinas, F Wolk, CP AF Leganes, F Fernandez-Pinas, F Wolk, CP TI A transposition-induced mutant of Nostoc ellipsosporum implicates an arginine-biosynthetic gene in the formation of cyanophycin granules and of functional heterocysts and akinetes SO MICROBIOLOGY-UK LA English DT Article DE akinete; arginine; cyanophycin; differentiation; heterocyst ID SP-STRAIN PCC-7120; BLUE-GREEN-ALGA; GAMMA-SEMIALDEHYDE DEHYDROGENASE; ANABAENA-CYLINDRICA; NUCLEOTIDE-SEQUENCE; ESCHERICHIA-COLI; ARGC GENE; CYANOBACTERIUM; DIFFERENTIATION; POLYSACCHARIDES AB In strain NE1 of Tn5-1058-mutagenized Nostoc ellipsosporum, the transposon was found within a gene whose translation product is similar in amino acid sequence to the arginine-biosynthetic protein N-acetylglutamate semialdehyde dehydrogenase encoded by argC of Bacillus subtilis. The argC reported from Anabaena sp. strain PCC 7120 hybridized to a sequence different from the one interrupted by the transposon in NE1. The newly identified gene from N. ellipsosporum was denoted argL. The argL mutation renders certain processes in strain NE1 conditionally dependent on provision of L-arginine. Heterocysts and apparent akinetes that formed in the absence of added L-arginine failed to fix dinitrogen or to germinate, respectively, and lacked granules of cyanophycin, composed of copolymers of arginine and aspartic acid. However, apparent akinetes that differentiated upon growth of the mutant in the presence of L-arginine plus nitrate formed cyanophycin granules and could regenerate a new culture. C1 Univ Autonoma Madrid, Fac Ciencias, Dept Biol, E-28049 Madrid, Spain. Michigan State Univ, MSU DOE, Plant Res Lab, E Lansing, MI 48824 USA. RP Leganes, F (reprint author), Univ Autonoma Madrid, Fac Ciencias, Dept Biol, E-28049 Madrid, Spain. EM francisco.leganes@uam.es OI Fernandez-Pinas, Francisca/0000-0002-7444-7601 NR 40 TC 16 Z9 17 U1 0 U2 1 PU SOC GENERAL MICROBIOLOGY PI READING PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING, BERKS, ENGLAND RG7 1AE SN 1350-0872 J9 MICROBIOL-UK JI Microbiology-(UK) PD JUL PY 1998 VL 144 BP 1799 EP 1805 PN 7 PG 7 WC Microbiology SC Microbiology GA 103KR UT WOS:000075000100011 PM 9695912 ER PT J AU Song, JJ Bajikar, S Decarlo, F Kang, YW Kustom, RL Mancini, DC Nassiri, A Lai, B Feinerman, AD White, V AF Song, JJ Bajikar, S Decarlo, F Kang, YW Kustom, RL Mancini, DC Nassiri, A Lai, B Feinerman, AD White, V TI LIGA-fabricated compact mm-wave linear accelerator cavities SO MICROSYSTEM TECHNOLOGIES LA English DT Article AB Millimeter-wave rf cavities for use in linear accelerators, free-electron lasers, and mm-wave undulators are under development at Argonne National Laboratory. Typical cavity dimensions are in the 1000 mu m range, and the overall length of the accelerator structure, which consists of 30-100 cavities, is about 50-100 mm. An accuracy of 0.2% in the cavity dimensions is necessary in order to achieve a high Q-factor of the cavity. To achieve this, these structures are being fabricated using deep X-ray lithography, electroforming, and assembly (LIGA). The first prototype cavity structures are designed for 108 GHz and 2 pi/3-mode operation. Input and output couplers are integrated with the cavity structures. The cavities are fabricated on copper substrates by electroforming copper into 1 mm-thick PMMA resists patterned by deep x-ray lithography and polishing the copper down to the desired thickness. These are fabricated separately and subsequently assembled with precision spacing and alignment using microspheres, optical fibers, or microfabricated spacers/alignment pieces. Details of the fabrication process, alignment, and assembly work are presented in here. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Illinois, Microfabricat Lab, Chicago, IL 60607 USA. Univ Wisconsin, Ctr Xray Lithog, Madison, WI 53706 USA. RP Song, JJ (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 7 Z9 7 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0946-7076 J9 MICROSYST TECHNOL JI Microsyst. Technol. PD JUL PY 1998 VL 4 IS 4 BP 193 EP 196 DI 10.1007/s005420050129 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Science & Technology - Other Topics; Materials Science; Physics GA 106EA UT WOS:000075115900009 ER PT J AU Lebensohn, RA Turner, PA Signorelli, JW Canova, GR Tome, CN AF Lebensohn, RA Turner, PA Signorelli, JW Canova, GR Tome, CN TI Calculation of intergranular stresses based on a large-strain viscoplastic self-consistent polycrystal model SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID PLASTIC-DEFORMATION; ZIRCONIUM; TEXTURE; CREEP AB We present here an extension of the viscoplastic self-consistent (VPSC) polycrystal model for the calculation of the intergranular Cauchy stresses in an aggregate. This method, which is based on the self-consistent treatment of incompressible aggregates proposed in 1987 by Molinari el al, is formulated using the inclusion formalism and full anisotropy is incorporated into it. The complete stress state in the grains is obtained by computing the deviatoric and the hydrostatic local deviations with respect to the overall corresponding magnitudes applied to the polycrystal. The extended VPSC model, followed by an elastic self-consistent unloading, is used to obtain the intergranular residual strains in the aggregate after large plastic deformation. The texture evolution and the hardening of the material are explicitly taken into account in the model. As an application, the model is used to predict intergranular residual states in Incoloy-800 plate after uniaxial deformation. C1 Univ Nacl Rosario, CONICET, Inst Fis Rosario, RA-2000 Rosario, Santa Fe, Argentina. Ecole Natl Super Phys Grenoble, GPM2, F-38402 St Martin Dheres, France. Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Lebensohn, RA (reprint author), Univ Nacl Rosario, CONICET, Inst Fis Rosario, 27 Febrero 210 Bis, RA-2000 Rosario, Santa Fe, Argentina. RI Lebensohn, Ricardo/A-2494-2008; Tome, Carlos/D-5058-2013 OI Lebensohn, Ricardo/0000-0002-3152-9105; NR 21 TC 34 Z9 35 U1 1 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD JUL PY 1998 VL 6 IS 4 BP 447 EP 465 DI 10.1088/0965-0393/6/4/011 PG 19 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 121GH UT WOS:000076004600011 ER PT J AU Rhee, M Zbib, HM Hirth, JP Huang, H de la Rubia, T AF Rhee, M Zbib, HM Hirth, JP Huang, H de la Rubia, T TI Models for long-/short-range interactions and cross slip in 3D dislocation simulation of BCC single crystals SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID INTERNAL-STRESSES; DEFORMATION; TENSILE AB Models and rules for short-range interactions, cross slip and long-range interactions of dislocation segments for implementation in a 3D dislocation dynamics (3DD) model are developed. Dislocation curves of arbitrary shapes are discretized into sets of straight segments of mixed dislocations. Long-range interactions are evaluated explicitly based on results from the theory of dislocations. Models for short-range interactions, including, annihilation, formation of jogs, junctions, and dipoles, are developed on the basis of a 'critical-force' criterion that captures the effect of the local fields from surrounding dislocations. In addition, a model for the cross-slip mechanism is developed and coupled with a Monte Carlo type analysis to simulate the development of double cross slip and composite slip. The model is then used to simulate stage I (easy glide) stress-strain behaviour in BCC single crystals, illustrating the feasibility of the 3DD model in predicting macroscopic properties such as dow stress and hardening, and their dependence on microscopic parameters such as dislocation mobility, dislocatjon structure, and pinning points. C1 Sch Mech & Mat Engn, Pullman, WA 99164 USA. Lawrence Livermore Natl Lab, Livermore, CA 90224 USA. RP Zbib, HM (reprint author), Sch Mech & Mat Engn, Pullman, WA 99164 USA. RI Huang, Hanchen/A-9323-2008 NR 41 TC 134 Z9 139 U1 3 U2 28 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD JUL PY 1998 VL 6 IS 4 BP 467 EP 492 DI 10.1088/0965-0393/6/4/012 PG 26 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 121GH UT WOS:000076004600012 ER PT J AU Halpern, AL Bruno, WJ AF Halpern, AL Bruno, WJ TI Evolutionary distances for protein-coding sequences: Modeling site-specific residue frequencies SO MOLECULAR BIOLOGY AND EVOLUTION LA English DT Article DE site-specific frequencies; evolutionary distances; selection; maximum likelihood; saturation; variable-rate models ID HIDDEN MARKOV-MODELS; MAXIMUM-LIKELIHOOD APPROACH; DNA-SEQUENCES; NUCLEOTIDE SUBSTITUTION; PHYLOGENY; MATRICES; TREES AB Estimation of evolutionary distances from coding sequences must take into account protein-level selection to avoid relative underestimation of longer evolutionary distances. Current modeling of selection via site-to-site rate heterogeneity generally neglects another aspect of selection, namely position-specific amino acid frequencies. These frequencies determine the maximum dissimilarity expected for highly diverged but functionally and structurally conserved sequences, and hence are crucial for estimating long distances. We introduce a codon-level model of coding sequence evolution in which position-specific amino acid frequencies are free parameters. In our implementation, these are estimated from an alignment using methods described previously. We use simulations to demonstrate the importance and feasibility of modeling such behavior; our model produces linear distance estimates over a wide range of distances, while several alternative models underestimate long distances relative to short distances. Site-to-site differences in rates, as well as synonymous/nonsynonymous and first/second/third-codon-position differences, arise as a natural consequence of the site-to-site differences in amino acid frequencies. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Santa Fe Inst, Santa Fe, NM 87501 USA. RP Halpern, AL (reprint author), Univ New Mexico, Hlth Sci Ctr, Dept Mol Genet & Microbiol, 915 Camino Salud, Albuquerque, NM 87131 USA. EM ahalpern@ender.unm.edu NR 36 TC 149 Z9 150 U1 0 U2 3 PU SOC MOLECULAR BIOLOGY EVOLUTION PI LAWRENCE PA PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0737-4038 J9 MOL BIOL EVOL JI Mol. Biol. Evol. PD JUL PY 1998 VL 15 IS 7 BP 910 EP 917 PG 8 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA ZX078 UT WOS:000074477200013 PM 9656490 ER PT J AU Li, GC Ouyang, HH Li, XL Nagasawa, H Little, JB Chen, DJ Ling, CC Fuks, Z Cordon-Cardo, C AF Li, GC Ouyang, HH Li, XL Nagasawa, H Little, JB Chen, DJ Ling, CC Fuks, Z Cordon-Cardo, C TI Ku70: A candidate tumor suppressor gene for murine T cell lymphoma SO MOLECULAR CELL LA English DT Article ID DEPENDENT PROTEIN-KINASE; SEVERE COMBINED IMMUNODEFICIENCY; V(D)J RECOMBINATION; HIRSCHSPRUNG DISEASE; CATALYTIC SUBUNIT; STRANDED-DNA; SCID MICE; MUTATION; REPAIR; MOUSE AB We present evidence that inactivation of the Ku70 gene leads to a propensity for malignant transformation both in vitro and in vivo. In vitro, Ku70(-/-) mouse fibroblasts displayed an increased rate of sister chromatid exchange and a high frequency of spontaneous neoplastic transformation. In vivo, Ku70(-/-) mice, known to be defective in B but not T lymphocyte maturation, developed thymic and disseminated T cell lymphomas at a mean age of 6 months with CD4(+)CD8(+) tumor cells. These findings directly demonstrate that Ku70 deficiency facilitates neoplastic growth and suggest a novel role of the Ku70 locus in tumor suppression. C1 Mem Sloan Kettering Canc Ctr, Dept Radiat Oncol, New York, NY 10021 USA. Mem Sloan Kettering Canc Ctr, Dept Phys Med, New York, NY 10021 USA. Mem Sloan Kettering Canc Ctr, Dept Pathol, New York, NY 10021 USA. Harvard Univ, Sch Publ Hlth, Radiobiol Lab, Boston, MA 02115 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Li, GC (reprint author), Mem Sloan Kettering Canc Ctr, Dept Radiat Oncol, 1275 York Ave, New York, NY 10021 USA. EM g-li@ski.mskcc.org FU NCI NIH HHS [CA-31397, CA-56909] NR 47 TC 171 Z9 171 U1 0 U2 2 PU CELL PRESS PI CAMBRIDGE PA 1050 MASSACHUSETTES AVE, CIRCULATION DEPT, CAMBRIDGE, MA 02138 USA SN 1097-2765 J9 MOL CELL JI Mol. Cell. PD JUL PY 1998 VL 2 IS 1 BP 1 EP 8 DI 10.1016/S1097-2765(00)80108-2 PG 8 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 106WR UT WOS:000075174500001 PM 9702186 ER PT J AU Heffelfinger, GS Ford, DM AF Heffelfinger, GS Ford, DM TI Massively parallel dual control volume grand canonical molecular dynamics with LADERA I. Gradient driven diffusion in Lennard-Jones fluids SO MOLECULAR PHYSICS LA English DT Article ID SIMULATION; ENSEMBLE; ALGORITHM; FLOW AB A new algorithm to enable the implementation of dual control volume grand canonical molecular dynamics (DCV-GCMD) on massively parallel (MP) architectures is presented. DCV-GCMD can be thought of as hybridization of molecular dynamics (MD) and grand canonical Monte Carlo (GCMC) and was developed recently to make possible the simulation of gradient-driven diffusion. The method has broad application to such problems as membrane separations, drug delivery systems, diffusion in polymers and zeolites, etc. The massively parallel algorithm for the DCV-GCMD method has been implemented in a code named LADERA which employs the short range Lennard-Jones potential for pure fluids and multicomponent mixtures including bulk and confined (single pore as well as amorphous solid materials) systems. Like DCV-GCMD, LADERA's MP algorithm can be thought of as a hybridization of two different algorithms, spatial MD and spatial GCMC. The DCV-GCMD method is described fully followed by the DCV-GCMD parallel algorithm employed in LADERA. The scaling characteristics of the new MP algorithm are presented together with the results of the application of LADERA to ternary and quaternary Lennard-Jones mixtures. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Heffelfinger, GS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Ford, David/C-4027-2008 NR 29 TC 36 Z9 36 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 JUL PY 1998 VL 94 IS 4 BP 659 EP 671 DI 10.1080/002689798167827 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZY609 UT WOS:000074640800008 ER PT J AU Ford, DM Heffelfinger, GS AF Ford, DM Heffelfinger, GS TI Massively parallel dual control volume grand canonical molecular dynamics with LADERA II. Gradient driven diffusion through polymers SO MOLECULAR PHYSICS LA English DT Article AB This paper, the second part of a series, extends the capabilities of the LADERA FORTRAN code for massively parallel dual control volume grand canonical molecular dynamics (DCV-GCMD). DCV-GCMD is a hybrid of two more common molecular simulation techniques (grand canonical Monte Carlo and molecular dynamics)which allows the direct molecular-level modelling of diffusion under a chemical potential gradient. The present version of the code, LADERA-B has the capability of modelling systems with explicit intramolecular interactions such as bonds, angles, and dihedral rotations. The utility of the new code for studying gradient-driven diffusion of small molecules through polymers is demonstrated by applying it to two model systems. LADERA-B includes another new feature, which is the use of neighbour lists in force calculations. This feature increases the speed of the code but presents several challenges in the parallel hybrid algorithm. There is discussion on how these problems were addressed and how our implementation results in a significant increase in speed over the original LADERA. Scaling results are presented for LADERA-B on two massively parallel message-passing machines. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ford, DM (reprint author), Texas A&M Univ, Dept Chem Engn, College Stn, TX 77843 USA. RI Ford, David/C-4027-2008 NR 12 TC 39 Z9 39 U1 0 U2 6 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD JUL PY 1998 VL 94 IS 4 BP 673 EP 683 DI 10.1080/002689798167836 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZY609 UT WOS:000074640800009 ER PT J AU Bench, G Corzett, MH De Yebra, L Oliva, R Balhorn, R AF Bench, G Corzett, MH De Yebra, L Oliva, R Balhorn, R TI Protein and DNA contents in sperm from an infertile human male possessing protamine defects that vary over time SO MOLECULAR REPRODUCTION AND DEVELOPMENT LA English DT Article DE sperm chromatin; reproduction; male infertility; single-cell elemental analysis ID 2 FORMS; CHROMATIN AB Sperm from 2 semen samples collected 6 months apart from an infertile male and 3 semen samples collected over an 18-month period from a fertile human male volunteer have been analyzed for their protamine and DNA content. Hup1M and Hup2b antibodies were used to detect the presence of protamines and protamine precursors in western blots of nuclear proteins isolated from pools of sperm. Phosphorus and sulfur contents, which can be used to estimate the nuclear DNA and protamine contents of sperm from fertile males, were measured within individual sperm heads from each semen sample by particle induced x-ray emission (PIXE). The single-cell data reveal no significant differences in the phosphorus and sulfur contents of sperm heads in the three semen samples obtained from the fertile male. For the initial semen sample produced by the infertile male, Western blot data show a normal complement of protamine 1, small amounts of mature protamine 2, and reveal large amounts of anti-protamine 2 reactive proteins with electrophoretic mobilities similar to protamine 2 precursors. Data from PIXE show elevated levels of sulfur within sperm heads compared with sperm from the fertile male. Western blot data exhibit no evidence of protamines or protamine 2 precursors in the second semen sample produced by the infertile male. Data from PIXE suggest that these sperm are highly deficient in sulfur and protamines. These results show that the degree of maturation of sperm cells present in the semen of some infertile males can vary with time. (C) 1998 Wiley-Liss, Inc. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. Univ Barcelona, Fac Med, Human Genome Res Grp, Barcelona 7, Spain. RP Bench, G (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, L-397, Livermore, CA 94550 USA. EM bench1@llnl.gov RI Oliva, Rafael/C-9741-2009 OI Oliva, Rafael/0000-0003-4876-2410 NR 24 TC 37 Z9 39 U1 1 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1040-452X J9 MOL REPROD DEV JI Mol. Reprod. Dev. PD JUL PY 1998 VL 50 IS 3 BP 345 EP 353 DI 10.1002/(SICI)1098-2795(199807)50:3<345::AID-MRD11>3.0.CO;2-3 PG 9 WC Biochemistry & Molecular Biology; Cell Biology; Developmental Biology; Reproductive Biology SC Biochemistry & Molecular Biology; Cell Biology; Developmental Biology; Reproductive Biology GA ZQ661 UT WOS:000073890400011 PM 9621311 ER PT J AU Gaasterland, T AF Gaasterland, T TI Structural genomics: Bioinformatics in the driver's seat SO NATURE BIOTECHNOLOGY LA English DT Article C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Gaasterland, T (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM gaasterland@mcs.anl.gov NR 9 TC 40 Z9 42 U1 0 U2 2 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1087-0156 J9 NAT BIOTECHNOL JI Nat. Biotechnol. PD JUL PY 1998 VL 16 IS 7 BP 625 EP 627 DI 10.1038/nbt0798-625 PG 3 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA ZX494 UT WOS:000074521800022 PM 9661193 ER PT J AU Nolan, JP Sklar, LA AF Nolan, JP Sklar, LA TI The emergence of flow cytometry for sensitive, real-time measurements of molecular interactions SO NATURE BIOTECHNOLOGY LA English DT Review DE technology; biosensor; fluorescence; fusion proteins ID FACTOR-VIII; RECEPTOR DYNAMICS; KINETIC-ANALYSIS; BINDING-SITES; MICROSPHERES; PURIFICATION; SPECIFICITY; ANTIBODIES; MEMBRANES; PROTEINS AB The analysis of macromolecular interactions is an essential element of biomedical research. Flow cytometry is uniquely capable of making sensitive and quantitative measurements of molecular interactions. These measurements can be made in real time with subsecond kinetic resolution using purified biomolecules or living cells. Combined with automated sample handling, these features make flow cytometry a versatile and robust technology for the analysis of molecular interactions. C1 Univ Calif Los Alamos Natl Lab, Natl Flow Cytometry Resource & Life Sci Div, Los Alamos, NM 87545 USA. Univ New Mexico, Ctr Canc, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Pathol, Albuquerque, NM 87131 USA. RP Nolan, JP (reprint author), Univ Calif Los Alamos Natl Lab, Natl Flow Cytometry Resource & Life Sci Div, POB 1663, Los Alamos, NM 87545 USA. EM nolan@telomere.lanl.gov; lsklar@salud.unm.edu FU NCRR NIH HHS [RR01315] NR 47 TC 94 Z9 96 U1 0 U2 24 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1087-0156 J9 NAT BIOTECHNOL JI Nat. Biotechnol. PD JUL PY 1998 VL 16 IS 7 BP 633 EP 638 DI 10.1038/nbt0798-633 PG 6 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA ZX494 UT WOS:000074521800025 PM 9661195 ER PT J AU Connolly, KM Wojciak, JM Clubb, RT AF Connolly, KM Wojciak, JM Clubb, RT TI Site-specific DNA binding using a variation of the double stranded RNA binding motif SO NATURE STRUCTURAL BIOLOGY LA English DT Letter ID CONJUGATIVE TRANSPOSITION; PROTEIN STRUCTURES; NMR; RECOMBINATION; REARRANGEMENT; SEQUENCES; PROGRAM; DOMAIN AB The integrase family of site-specific recombinases catalyze a diverse array of DNA rearrangements in archaebacteria, eubacteria and yeast. The solution structure of the DNA binding domain of the integrase protein from the conjugative transposon Tn916 has been determined using NMR spectroscopy. The structure provides the first insights into distal site DNA binding by a site-specific integrase and reveals that the N-terminal domain is structurally similar to the double stranded RNA binding domain (dsRBD). The results of chemical shift mapping experiments suggest that the integrase protein interacts with DNA using residues located on the face of its three stranded beta-sheet. This surface differs from the proposed RNA binding surface in dsRBDs, suggesting that different surfaces on the same protein fold can be used to bind DNA and RNA. C1 Univ Calif Los Angeles, Dept Biochem & Chem, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, US DOE, Lab Struct Biol & Genet, Los Angeles, CA 90095 USA. RP Clubb, RT (reprint author), Univ Calif Los Angeles, Dept Biochem & Chem, 405 Hilgard Ave, Los Angeles, CA 90095 USA. EM rclubb@mbi.ucla.edu NR 39 TC 35 Z9 36 U1 0 U2 0 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 JUL PY 1998 VL 5 IS 7 BP 546 EP 550 DI 10.1038/799 PG 5 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA ZW821 UT WOS:000074451700012 PM 9665166 ER PT J AU Bittner, AC Echeverria, D Woods, JS Aposhian, HV Naleway, C Martin, MD Mahurin, RK Heyer, NJ Cianciola, M AF Bittner, AC Echeverria, D Woods, JS Aposhian, HV Naleway, C Martin, MD Mahurin, RK Heyer, NJ Cianciola, M TI Behavioral effects of low-level exposure to Hg-0 among dental professionals: A cross-study evaluation of psychomotor effects SO NEUROTOXICOLOGY AND TERATOLOGY LA English DT Article DE elemental mercury; dental exposures; psychomotor; CNS; occupational; chronic ID ELEMENTAL MERCURY; INORGANIC MERCURY; URINARY MERCURY; WORKERS; DENTISTS; VAPOR; PERFORMANCE AB A cross-study design was used to evaluate the sensitivities of five psychomotor tasks previously used to assess preclinical effects of low-level Hg-0 (urinary less than or equal to 55 mu g/l). Pooling dental professional subject populations from six studies conducted over the last 6 years, a larger study population was obtained with a high degree of uniformity (N = 230). The five psychomotor tests were: Intentional Hand Steadiness Test (IHST); Finger Tapping; The One-Hole Test; NES Simple Reaction Time (SRT); and Hand Tremor. Multivariate analyses were conducted following the hierarchical analysis of multiple responses (HAMR) approach. First, multiple scores of each test were combined into a single-factor (or related summary) variable and its reliability was estimated. Second, multiple regression analyses were conducted including log-transformed [Hg-0]U levels, age, gender, and alcohol consumption in each model. Computed were both B and b(u), the magnitudes of the log-Hg-0 standardized coefficient, respectively uncorrected and corrected for dependent variable attenuation due to unreliability. Results indicated remarkable differences in the effects of relative level of Hg-0 on psychomotor performance. Significant associations were found for the IHST factor (B = 0.415, p < 10(-6)), followed by finger tapping, which was relatively meager and insignificant (B = 0.141, p = 0.17). The IHST results hold the greatest occupational relevance for dental professionals who rely on manual dexterity in restorative dentistry. Further, this statistical approach is recommended in future studies for condensation of multiple scores into summary scores with enhanced reliabilities useful in correcting for attenuation relationships (B(u)s) with exposure levels. (C) 1998 Elsevier Science Inc. C1 Battelle Seattle Res Ctr, Ctr Publ Hlth Res & Evaluat, Seattle, WA 98105 USA. Univ Washington, Dept Environm Hlth, Seattle, WA 98195 USA. Univ Arizona, Dept Mol & Cellular Biol, Tucson, AZ 85721 USA. Amer Dent Assoc Hlth Fdn, Chicago, IL USA. Univ Washington, Dept Oral Med, Seattle, WA 98195 USA. Univ Washington, Dept Psychiat, Seattle, WA 98195 USA. RP Echeverria, D (reprint author), Battelle Seattle Res Ctr, Ctr Publ Hlth Res & Evaluat, 4000 NE 41st St, Seattle, WA 98105 USA. FU NIDCR NIH HHS [DE11712]; NIEHS NIH HHS [ES04696, ES04940] NR 40 TC 38 Z9 39 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0892-0362 J9 NEUROTOXICOL TERATOL JI Neurotoxicol. Teratol. PD JUL-AUG PY 1998 VL 20 IS 4 BP 429 EP 439 DI 10.1016/S0892-0362(98)00006-3 PG 11 WC Neurosciences; Toxicology SC Neurosciences & Neurology; Toxicology GA 105TF UT WOS:000075089100007 PM 9697969 ER PT J AU Saxe, H Ellsworth, DS Heath, J AF Saxe, H Ellsworth, DS Heath, J TI Tree and forest functioning in an enriched CO2 atmosphere SO NEW PHYTOLOGIST LA English DT Review DE elevated carbon dioxide (CO2); drought; forests; nutrients; photosynthesis; stomatal conductance ID ELEVATED CARBON-DIOXIDE; PICEA-ABIES L; PONDEROSA PINE-SEEDLINGS; BETULA-PENDULA ROTH; GAS-EXCHANGE RESPONSES; LONG-TERM EXPOSURE; CO2-INDUCED GROWTH ENHANCEMENTS; BEECH FAGUS-SYLVATICA; WATER-LOSS REGULATION; SITCHENSIS BONG CARR AB Forests exchange large amounts of CO2 with the atmosphere and can influence and be influenced by atmospheric CO2. There has been a recent proliferation of literature on the effects of atmospheric CO2 on forest trees. More than 300 studies of trees on five different continents have been published in the last five years. These include an increasing number of field studies with a long-term focus and involving CO2 x stress or environment interactions. The recent data on long-term effects of elevated atmospheric CO2 on trees indicate a potential for a persistent enhancement of tree growth for several years, although the only relevant long-term datasets currently available are for juvenile trees. The current literature indicates a significantly larger average long-term biomass increment under elevated CO2 for conifers (130%) than for deciduous trees (49%) in studies not involving stress components. However, stimulation of photosynthesis by elevated CO2 in long-term studies was similar for conifers (62 %) and deciduous trees (53 %). Recent studies indicate that elevated CO2 causes a more persistent stimulation of biomass increment and photosynthesis than previously expected. Results of seedling studies, however, might not be applicable to other stages of tree development because of complications of age-dependent and size-dependent shifts in physiology and carbon allocation, which are accelerated by elevated CO2. In addition, there are many possible avenues to down-regulation, making the predicted canopy CO2 exchange and growth of mature trees and forests in a CO2-rich atmosphere uncertain. Although, physiological down-regulation of photosynthetic rates has been documented in field situations, it is rarely large enough to offset entirely photosynthetic gains in elevated CO2. A persistent growth stimulation of individual mature trees has been demonstrated although this effect is more uncertain in trees in natural stands. Resource interactions can both constrain tree responses to elevated CO2 and be altered by them. Although drought can reduce gas-exchange rates and offset the benefits of elevated CO2, even in well watered trees, stomatal conductance is remarkably less responsive to elevated CO2 than in herbaceous species. Stomata of a number of tree species have been demonstrated to be unresponsive to elevated CO2. We conclude that positive effects of CO2 on leaf area can be at least as important in determining canopy transpiration as negative, direct effects of CO2 on stomatal aperture. With respect to nutrition, elevated CO2 has the potential to alter tree-soil interactions that might influence future changes in ecosystem productivity. There is continued evidence that in most cases nutrient limitations diminish growth and photosynthetic responses to elevated CO2 at least to some degree, and that elevated CO2 can accelerate the appearance of nutrient limitations with increasing time of treatment. In many studies, tree biomass responses to CO2 are artefacts in the sense that they are merely responses to CO2-induced changes in internal nutritional status of the tree. There are numerous interactions between CO2 and factors of the biotic and abiotic environment. The importance of increasing atmospheric CO2 concentrations for productivity is likely to be overestimated if these are not taken into account. Many interactions, however, are simply additive rather than synergistic or antagonistic. This appears to hold true for many parameters under elevated CO2 in combination with temperature, elevated O-3, and other atmospheric pollutants. However, there is currently little evidence that elevated CO2 will counteract O-3 damage. When the foliage content of C, mineral nutrients and secondary metabolites is altered by elevated CO2, tree x insect interactions are modified. In most trees, mycorrhizal interactions might be less important for direct effects of CO2 than for alleviating general nutrient deficiencies. Since many responses to elevated CO2 and their interactions with stress show considerable variability among species/genotypes, one principal research need is for comparative studies of a large variety of woody species and ecosystems under realistic conditions. We still need more long-term experiments on mature trees and stands to address critical scaling issues likely to advance our understanding of responses to elevated CO2 at different stages of forest development and their interactions with climate and environment. The only tools available at present for coping with the consequences of rising CO2 are management of resources and selection of genotypes suitable for the future climate and environment. C1 Royal Vet & Agr Univ, Arboretum, Inst Bot Dendrol & Forest Genet, DK-2970 Horsholm, Denmark. Brookhaven Natl Lab, Environm Biol & Instrumentat Div, Upton, NY 11973 USA. Univ Lancaster, Inst Environm & Nat Sci, Lancaster LA1 4YQ, England. RP Saxe, H (reprint author), Royal Vet & Agr Univ, Arboretum, Inst Bot Dendrol & Forest Genet, Kirkegaardsvej 3A, DK-2970 Horsholm, Denmark. EM hsa@kvl.dk OI Ellsworth, David/0000-0002-9699-2272 NR 275 TC 503 Z9 534 U1 19 U2 200 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0028-646X J9 NEW PHYTOL JI New Phytol. PD JUL PY 1998 VL 139 IS 3 BP 395 EP 436 DI 10.1046/j.1469-8137.1998.00221.x PG 42 WC Plant Sciences SC Plant Sciences GA 107VB UT WOS:000075230700001 ER PT J AU Lazarus, EA Hyatt, AW Jackson, GL Humphreys, DA AF Lazarus, EA Hyatt, AW Jackson, GL Humphreys, DA TI Using a multipole expansion for startup in the DIII-D tokamak SO NUCLEAR FUSION LA English DT Article ID BORONIZATION; PLASMA AB The magnetic field null conditions for plasma startup in DIII-D are established using a multipole expansion of the flux contribution from each element of the poloidal coil set to compute the vacuum magnetic field in real time using the measured coil currents. The use of this procedure has improved the breakdown conditions, as evidenced by the formation of the current channel with a toroidal electric field as low as 0.4 V/m without RF assistance. This represents a significant improvement over previous normal operation. Improved null conditions enhance the sensitivity of the minimum loop voltage to the wall conditions of the vacuum vessel. Results relating the breakdown voltage to carbon impurities are presented. It is shown that the observed difference between the radius of the poloidal field null and the radius of plasma initiation is a manifestation of finite aspect ratio, explained by the variation of the electric potential along the field line from the breakdown region to the wall. C1 Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Lazarus, EA (reprint author), Gen Atom Co, San Diego, CA 92186 USA. NR 15 TC 14 Z9 14 U1 0 U2 3 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD JUL PY 1998 VL 38 IS 7 BP 1083 EP 1096 DI 10.1088/0029-5515/38/7/310 PG 14 WC Physics, Fluids & Plasmas SC Physics GA 116QP UT WOS:000075736300010 ER PT J AU Jardin, SC Schmidt, JA AF Jardin, SC Schmidt, JA TI Numerical simulation of feedback stabilization of axisymmetric modes in tokamaks using driven halo currents SO NUCLEAR FUSION LA English DT Article ID TSC AB The Tokamak Simulation Code (TSC) has been used to model a new method of feedback stabilization of the axisymmetric instability in tokamaks using driven halo (or scrape-off layer) currents. The method appears to be feasible for a wide range of plasma edge parameters. It may offer advantages over the more conventional method of controlling this instability when applied in a reactor environment. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Jardin, SC (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Jardin, Stephen/E-9392-2010 NR 7 TC 3 Z9 3 U1 0 U2 3 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD JUL PY 1998 VL 38 IS 7 BP 1105 EP 1112 DI 10.1088/0029-5515/38/7/312 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 116QP UT WOS:000075736300012 ER PT J AU Hara, K Hata, K Kim, S Mishina, M Sano, M Seiya, Y Takikawa, K Tanaka, M Yasuoka, K AF Hara, K Hata, K Kim, S Mishina, M Sano, M Seiya, Y Takikawa, K Tanaka, M Yasuoka, K TI Radiation hardness and mechanical durability of Kuraray optical fibers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE fiber tracker; scintillating fiber; radiation damage; fiber transmittance AB The radiation hardness of Kuraray 3HF scintillating and clear optical fibers has been investigated using Co-60 gamma-rays in the dose range 0.4-500 krad. Significant initial degradation in the attenuation length was observed both for 3HF and clear fibers at a dose as small as 10 krad. The radiation hardness of both the scintillating and clear fibers is identical if it is expressed in terms of the ratio of the attenuation lengths after to before irradiation. The radiation damage of 3HF fibers was observed to recover substantially with a time scale of a few months. The attenuation length and mechanical durability against bending were measured for clear fibers by changing S parameter which characterizes the softness of the fibers. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Tsukuba, Inst Phys, Tsukuba, Ibaraki 305, Japan. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Hara, K (reprint author), Univ Tsukuba, Inst Phys, Tsukuba, Ibaraki 305, Japan. NR 10 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1998 VL 411 IS 1 BP 31 EP 40 DI 10.1016/S0168-9002(98)00281-2 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 100VK UT WOS:000074835900003 ER PT J AU Shiltsev, VD AF Shiltsev, VD TI Fast PIN-diode beam loss monitors at Tevatron SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB The article is devoted to results of fine temporal structure of particle losses in the Tevatron ring obtained with use of fast beam loss monitors (BLM) based on PIN-diodes. In the Tevatron fixed target operation regime, these monitors were able to distinguish proton losses from bunches spaced by only 19 ns. Besides measurements of main characteristics of the BLMs, we studied the proton losses over 10 decades of time intervals - from a dozen of minutes to a dozen of nanoseconds. Due to huge dynamical range and fast response the PIN-BLMs perfectly ht the task of the beam loss detection at the Tevatron collider upgrade with as small as 132 ns bunch spacing. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. RP Shiltsev, VD (reprint author), Fermi Natl Accelerator Lab, MS 221,POB 500, Batavia, IL 60510 USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1998 VL 411 IS 1 BP 81 EP 92 DI 10.1016/S0168-9002(98)00297-6 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 100VK UT WOS:000074835900009 ER PT J AU Muhrer, G Russell, GJ Ferguson, PD AF Muhrer, G Russell, GJ Ferguson, PD TI Flat target neutronics SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE spallation source; target station AB In this paper we will discuss the possibility of using a flat tungsten target as the target of a neutron spallation source. Therefore we investigated what influence the components of the target station, such as reflector material, moderator geometry, decoupler and target geometry, have on the neutronics of the target. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RP Muhrer, G (reprint author), Hahn Meitner Inst Kernforsch Berlin GmbH, Glienicker Str 100, D-14109 Berlin, Germany. RI Lujan Center, LANL/G-4896-2012; OI Ferguson, Phillip/0000-0002-7661-4223 NR 6 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1998 VL 411 IS 1 BP 137 EP 152 DI 10.1016/S0168-9002(98)00309-X PG 16 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 100VK UT WOS:000074835900015 ER PT J AU Pogorelsky, IV AF Pogorelsky, IV TI Ultra-bright X-ray and gamma sources by Compton backscattering of CO2 laser beams SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE X-rays; CO2 laser; electron beam; Compton scattering ID THOMSON SCATTERING; PULSES; ACCELERATION; COLLIDERS; LIGHT AB A picosecond laser interacting with a relativistic electron beam behaves like a virtual wiggler of an extremely short period equal to half of the laser wavelength. This approach opens a route to compact, high-brightness laser synchrotron sources (LSS). We discuss how the emerging terawatt picosecond CO2 laser technology facilitates achieving the ultra-high peak flux and brightness desirable for LSS applications in science and technology. The first laser of this class is under development at the BNL Accelerator Test Facility (ATF). Together with the high-brightness 50 MeV electron beam available at the ATF, this laser will be used for a prototype LSS demonstration. Flashes of collimated 4.7 keV (2.6 Angstrom) X-rays of 3 ps pulse duration, with a flux of similar to 10(22) photons/s, may be produced via linear Compton backscattering. This is several orders of magnitude above the peak numbers attained by the conventional synchrotron sources. Exploiting the promising approach to a high-gradient laser wakefield accelerator, a "table-top" wakefield gamma LSS may become feasible in the near future. The prospective gamma-gamma and e(+/-)-gamma colliders in the TeV energy range are among the advanced applications of picosecond CO2 laser technology. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Accelerator Test Facil, Upton, NY 11973 USA. RP Pogorelsky, IV (reprint author), Brookhaven Natl Lab, Accelerator Test Facil, 725C, Upton, NY 11973 USA. EM igor@bnl.gov NR 20 TC 24 Z9 30 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 1998 VL 411 IS 1 BP 172 EP 187 DI 10.1016/S0168-9002(98)00259-9 PG 16 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 100VK UT WOS:000074835900018 ER PT J AU Schweikhard, L Beiersdorfer, P Brown, GV Lopez-Urrutia, JRC Utter, SB Widmann, K AF Schweikhard, L Beiersdorfer, P Brown, GV Lopez-Urrutia, JRC Utter, SB Widmann, K TI Pulsed gas injection for X-ray spectroscopy of highly charged ions stored in the magnetic trapping mode of an electron beam ion trap SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE EBIT; X-ray spectroscopy; Penning trap; charge exchange; uranium; highly charged ions ID CAPTURE; COLLISIONS AB Highly charged atoms produced in an electron beam ion trap were stored after the electron beam was turned off by operating the trap in the magnetic trapping mode. Such storage allowed monitoring charge exchange reactions between the stored ions and residual neutral gas present in the trap by X-ray detection. The charge exchange reactions were enhanced by the application of a pulse of neutral gas. The method was exemplified for the case of H-like uranium interacting with neutral neon, where the K-shell X-rays and the series limit for the electron capture of U91+ were observed. Published by Elsevier Science B.V. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA. Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RP Beiersdorfer, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, POB 808,Mailstop L-421, Livermore, CA 94550 USA. RI Crespo Lopez-Urrutia, Jose R./F-7069-2011 OI Crespo Lopez-Urrutia, Jose R./0000-0002-2937-8037 NR 23 TC 21 Z9 21 U1 1 U2 2 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 JUL PY 1998 VL 142 IS 3 BP 245 EP 252 DI 10.1016/S0168-583X(98)00281-X PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 104UN UT WOS:000075034400002 ER PT J AU Wutte, D Freedman, S Gough, R Lee, Y Leitner, M Leung, KN Lyneis, C Pickard, DS Williams, MD Xie, ZQ AF Wutte, D Freedman, S Gough, R Lee, Y Leitner, M Leung, KN Lyneis, C Pickard, DS Williams, MD Xie, ZQ TI Development of an rf driven multicusp ion source for nuclear science experiments SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE multicusp ion source; rf driven multicusp ion source; plasma ion source; radioactive ion beams AB A compact 13.56 MHz radio-frequency (rf) driven multicusp ion source is under development at Lawrence Berkeley National Laboratory (LBNL) for radioactive ion beam applications. In this paper we describe the ion source design and the general ion source performance using H-2, Ar, Xe gas and a 90% Ar/10% CO gas mixture for generating the discharge plasma. The following ion source characteristics have been analyzed: extractable ion current, ion species distributions, ionization efficiency for nobel gases, axial energy spread and ion beam emittance measurements. This ion source can generate ion current densities of approximately 60 mA/cm(2). (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Tech Univ Vienna, Inst Allgemeine Phys, Vienna, Austria. RP Wutte, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM dwutte@mhl.lbl.gov NR 6 TC 9 Z9 13 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JUL PY 1998 VL 142 IS 3 BP 409 EP 416 DI 10.1016/S0168-583X(98)00221-3 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 104UN UT WOS:000075034400020 ER PT J AU Gatley, SJ Ding, YS Brady, D Gifford, AN Dewey, SL Carroll, FI Fowler, JS Volkow, ND AF Gatley, SJ Ding, YS Brady, D Gifford, AN Dewey, SL Carroll, FI Fowler, JS Volkow, ND TI In vitro and ex vivo autoradiographic studies of nicotinic acetylcholine receptors using [F-18]fluoronorchloroepibatidine in rodent and human brain SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE epibatidine; nicotinic receptor; thalamus; fluorine-18; phosphor imaging ID H-3 CYTISINE BINDING; RAT-BRAIN; CHOLINERGIC RECEPTORS; MOUSE-BRAIN; REGIONAL DISTRIBUTION; ALPHA-BUNGAROTOXIN; EPIBATIDINE; SITES; MEMBRANES; THALAMUS AB A fluorine-18-labeled analog of the potent nicotinic agonist epibatidine is a candidate radioligand for positron emission tomographic (PET) studies of nicotinic acetylcholine receptors (nAcChR). Following intravenous administration of [F-18]exo-2-(2'-fluoro-5'-pyridinyl)-7-azabicylo[2.2.1]heptane (NFEP), high uptake in thalamus was visualized in sections of mouse and rat brain by autoradiography using a phosphor imaging, device. Binding of [[F-18]NFEP to rat thalamic homogenate was consistent with a single class of binding site with a Kd value of 71 FM. In vitro autoradiography of thaw-mounted sections of human thalamus revealed a heterogeneous pattern of binding; Bmax values for ventrolateral nucleus, insular cortex and dorsomedial nucleus, and internal capsule were 20, 8, and 3 pmol/cc of tissue, respectively. However, similar Kd values close to 50 pM were calculated for all regions. These studies support the suitability of [F-18]NFEP as a radioligand for PET studies of nAcChR in the living human brain. NUCL MED BIOL 25;5: 449-454 1998. (C) 1998 Elsevier Science Inc. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NIA, Neurosci Lab, Bethesda, MD 20892 USA. Res Triangle Inst, Res Triangle Pk, NC 27709 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11786 USA. RP Gatley, SJ (reprint author), Brookhaven Natl Lab, Dept Med, 490 Bell Ave, Upton, NY 11973 USA. FU NINDS NIH HHS [NS15380] NR 48 TC 20 Z9 21 U1 2 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD JUL PY 1998 VL 25 IS 5 BP 449 EP 454 DI 10.1016/S0969-8051(98)00007-9 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZV536 UT WOS:000074314800002 PM 9720662 ER PT J AU Ooguri, H AF Ooguri, H TI Gauge theories on branes SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 2nd Trieste Conference on Duality Symmetries in String Theory / Spring School on String Theory, Gauge Theory and Quantum Gravity CY APR 01-12, 1997 CL TRIESTE, ITALY ID YANG-MILLS THEORY; SUPERSYMMETRIC QCD; F-THEORY; N=2; DUALITY; COMPACTIFICATIONS; SINGULARITIES; BREAKING C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Theory Grp, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, 366 Le Conte Hall, Berkeley, CA 94720 USA. RI Ooguri, Hirosi/A-4407-2011; OI Ooguri, Hirosi/0000-0001-6021-3778 NR 25 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JUL PY 1998 VL 67 BP 172 EP 179 DI 10.1016/S0920-5632(98)00129-7 PG 8 WC Physics, Particles & Fields SC Physics GA ZH804 UT WOS:000073149300017 ER PT J AU Demarteau, M AF Demarteau, M TI Electroweak results from hadron colliders SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97) CY JUN 22-28, 1997 CL CAPRI, ITALY SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept ID W-BOSON MASS; YAN K-FACTOR; ROOT-S=1.8 TEV; P(P)OVER-BAR COLLISIONS; PARTON DISTRIBUTIONS; CONTACT INTERACTION; PBARP COLLISIONS; GAMMA COUPLINGS; SECTOR; LIMITS AB A review of recent electroweak results from hadron colliders is given. Properties of the W+/- and Z(0) gauge bosons using final states containing electrons and muons based on large integrated luminosities are presented. The emphasis is placed on the measurement of the mass of the W boson and the measurement of trilinear gauge boson couplings. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Demarteau, M (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 45 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JUL PY 1998 VL 66 BP 12 EP 24 DI 10.1016/S0920-5632(98)00003-6 PG 13 WC Physics, Particles & Fields SC Physics GA ZH781 UT WOS:000073147000003 ER PT J AU Landsberg, G AF Landsberg, G TI Trilinear gauge couplings at the Fermilab Tevatron SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97) CY JUN 22-28, 1997 CL CAPRI, ITALY SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept ID ROOT-S=1.8 TEV; P(P)OVER-BAR COLLISIONS; PHOTON COUPLINGS; GAMMA COUPLINGS; WZ PRODUCTION; LIMITS; WW; SEARCH AB Recent trilinear gauge boson couplings measurements by the CDF and DO Collaborations at the Fermilab Tevatron are presented. The measurements were done by analyzing diboson production in multiple decay channels and final states. No deviations from the Standard Model description of the WWZ, WW gamma, ZZ gamma and Z gamma gamma vertices were found. Limits on anomalous gauge couplings set by these analyses are the tightest available to date. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Landsberg, G (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. OI Landsberg, Greg/0000-0002-4184-9380 NR 15 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD JUL PY 1998 VL 66 BP 79 EP 82 DI 10.1016/S0920-5632(98)00014-0 PG 4 WC Physics, Particles & Fields SC Physics GA ZH781 UT WOS:000073147000014 ER PT J AU Flattum, E AF Flattum, E TI Measurement of the W boson mass at the Tevatron SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97) CY JUN 22-28, 1997 CL CAPRI, ITALY SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept ID DECAY AB Presented are measurements of the W boson mass from the Dempty set and CDF collaborations at the Tevatron from the 1994-1996 run. The W events are produced in
collisions at root s = 1.8 TeV. The W mass extracted from W --> e nu decays at Dempty set is determined to be 80.45+/-0.12 GeV; and from W --> mu nu decays at CDF is 80.43+/-0.16 GeV. The world average W mass from the hadron collider measurements is 80.41+/-0.09 GeV.
C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA.
RP Flattum, E (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA.
NR 19
TC 0
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U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0920-5632
J9 NUCL PHYS B-PROC SUP
JI Nucl. Phys. B-Proc. Suppl.
PD JUL
PY 1998
VL 66
BP 108
EP 111
DI 10.1016/S0920-5632(98)00021-8
PG 4
WC Physics, Particles & Fields
SC Physics
GA ZH781
UT WOS:000073147000021
ER
PT J
AU Para, A
AF Para, A
TI Neutrino oscillations experiments: A review
SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS
LA English
DT Article; Proceedings Paper
CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97)
CY JUN 22-28, 1997
CL CAPRI, ITALY
SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept
AB This is an attempt to summarize three sessions of lively discussions, presentations of results and exchanges of new ideas. Present status and outlook of the future searches for neutrino oscillations is summarized.
C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA.
RP Para, A (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA.
NR 0
TC 0
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U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0920-5632
J9 NUCL PHYS B-PROC SUP
JI Nucl. Phys. B-Proc. Suppl.
PD JUL
PY 1998
VL 66
BP 335
EP 341
DI 10.1016/S0920-5632(98)00058-9
PG 7
WC Physics, Particles & Fields
SC Physics
GA ZH781
UT WOS:000073147000058
ER
PT J
AU Mills, GB
AF Mills, GB
TI Neutrino oscillation results from LSND
SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS
LA English
DT Article; Proceedings Paper
CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97)
CY JUN 22-28, 1997
CL CAPRI, ITALY
SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept
ID (NU)OVER-BAR(MU)->(NU)OVER-BAR(E) OSCILLATIONS; SEARCH; FACILITY;
PHYSICS; BEAM; ISIS
AB The Liquid Scintillator Neutrino Detector (LSND) experiment at Los Alamos has conducted searches for <(nu)over bar>(mu) --> <(nu)over bar>(e) oscillations by using <(nu)over bar>(mu) from mu(+) decay at rest and for nu(mu) --> nu(e) oscillations using nu(mu) from pi(+) decay in flight. For the <(nu)over bar>(mu) --> <(nu)over bar>(e) search, a total excess of 51.8(-16.9)(+18.7) +/- 8.0 events is observed with e(+) energy between 20 and 60 MeV, while for the nu(mu) --> nu(e) search, a total excess of 18.1 +/- 6.6 +/- 4.0 events is observed with e(-) energy between 60 and 200 MeV. If attributed to neutrino oscillations, these excesses correspond to oscillation probabilities (averaged over the experimental energies and spatial acceptances) of (0.31 +/- 0.12 +/- 0.05)% and (0.26 +/- 0.10 +/- 0.05)%, respectively.
C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
RP Mills, GB (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
NR 14
TC 0
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U1 0
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PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0920-5632
J9 NUCL PHYS B-PROC SUP
JI Nucl. Phys. B-Proc. Suppl.
PD JUL
PY 1998
VL 66
BP 382
EP 386
DI 10.1016/S0920-5632(98)00069-3
PG 5
WC Physics, Particles & Fields
SC Physics
GA ZH781
UT WOS:000073147000069
ER
PT J
AU Adler, S
AF Adler, S
TI Status report on the search for K+->pi(+)nu(nu)over-bar and prospects
for the search for K-L ->pi(0)nu(nu)over-bar
SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS
LA English
DT Article; Proceedings Paper
CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97)
CY JUN 22-28, 1997
CL CAPRI, ITALY
SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept
ID K->PI-NU(NU)OVER-BAR; MATRIX
AB The status of the search for K+ --> pi(+)nu(nu)over-bar and future prospects for the search for K-L --> pi(0)nu(nu)over-bar are outlined in this report. AGS experiment 787, currently searching for the charged decay mode, has reached a single event sensitivity of 4.2 x 10(-10) with total background similar to 3 x 10(-11). Proposed AGS experiment 926 will search for the neutral version of this decay. Initial studies indicate that at the current Standard Model predicted rate for this decay, and 80 weeks of AGS 2000 running time [1], on the order of 70 K-L --> pi(0)nu(nu)over-bar should be recorded with a background level of less than 10 events.
C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA.
RP Adler, S (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA.
NR 7
TC 0
Z9 0
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0920-5632
J9 NUCL PHYS B-PROC SUP
JI Nucl. Phys. B-Proc. Suppl.
PD JUL
PY 1998
VL 66
BP 466
EP 468
DI 10.1016/S0920-5632(98)00086-3
PG 3
WC Physics, Particles & Fields
SC Physics
GA ZH781
UT WOS:000073147000086
ER
PT J
AU Ben-David, R
AF Ben-David, R
TI Status of the KTeV experiment at Fermilab
SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS
LA English
DT Article; Proceedings Paper
CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97)
CY JUN 22-28, 1997
CL CAPRI, ITALY
SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept
ID CP-VIOLATION; BRANCHING RATIO; LIMIT; DECAYS
AB The KTeV experiment is a fixed target experiment at Fermilab. Its primary goal is the search for direct CP violation in the decay of neutral kaons. Its current status and some preliminary results will be discussed.
C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA.
RP Ben-David, R (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA.
NR 13
TC 3
Z9 3
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0920-5632
J9 NUCL PHYS B-PROC SUP
JI Nucl. Phys. B-Proc. Suppl.
PD JUL
PY 1998
VL 66
BP 473
EP 477
DI 10.1016/S0920-5632(98)00088-7
PG 5
WC Physics, Particles & Fields
SC Physics
GA ZH781
UT WOS:000073147000088
ER
PT J
AU Greenlee, H
AF Greenlee, H
TI Top quark results from the Tevatron
SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS
LA English
DT Article; Proceedings Paper
CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97)
CY JUN 22-28, 1997
CL CAPRI, ITALY
SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept
ID PRODUCTION CROSS-SECTION; COLLISIONS
AB The CDF and Dempty set collaborations have collected top quark data samples consisting of several dozen events each. Using these data samples, the two Tevatron experiments have measured the top quark mass and pair production cross section in a variety of decay channels, including the act-called dilepton, lepton plus jets and all jets channels. The combined top quark mass from both experiments in the lepton plus jets channels is m(t) = 175.6+/-5.5 GeV/c(2). Additionally, upper limits have been obtained for certain rare or nonstandard (FCNC and charged Higgs) top quark decays.
C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA.
RP Greenlee, H (reprint author), Fermi Natl Accelerator Lab, MS 357,POB 500, Batavia, IL 60510 USA.
NR 15
TC 0
Z9 0
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0920-5632
J9 NUCL PHYS B-PROC SUP
JI Nucl. Phys. B-Proc. Suppl.
PD JUL
PY 1998
VL 66
BP 502
EP 505
DI 10.1016/S0920-5632(98)00095-4
PG 4
WC Physics, Particles & Fields
SC Physics
GA ZH781
UT WOS:000073147000095
ER
PT J
AU Crawford, G
AF Crawford, G
TI Recent progress in B-s mixing measurements
SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS
LA English
DT Article; Proceedings Paper
CT XVI Workshop on Weak Interactions and Neutrinos (WIN 97)
CY JUN 22-28, 1997
CL CAPRI, ITALY
SP Univ Napoli, Phys Dept, Ist Nazl Fis Nucl, Azienda Autonoma Cura Soggiomo Turismo, Isola Capri, Hamamatsu Photon Italia Srl, CAEN, Nikon Europe B V Instruments Dept
AB We review the status of B-s mixing measurements from LEP experiments, including new results from DELPHI. We briefly review the various experimental techniques used and their limitations and discuss the possibilities for improving these measurements in the near future. Including the new DELPHI results the combined world average limit on the B-s oscillation frequency is Delta m(s) > 8.4ps(-1) at 95% CL.
C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
RP Crawford, G (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
NR 8
TC 0
Z9 0
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0920-5632
J9 NUCL PHYS B-PROC SUP
JI Nucl. Phys. B-Proc. Suppl.
PD JUL
PY 1998
VL 66
BP 510
EP 513
DI 10.1016/S0920-5632(98)00097-8
PG 4
WC Physics, Particles & Fields
SC Physics
GA ZH781
UT WOS:000073147000097
ER
PT J
AU McLaughlin, HE
Hendricks, JS
AF McLaughlin, HE
Hendricks, JS
TI Performance of scientific computing platforms with MCNP4B
SO NUCLEAR SCIENCE AND ENGINEERING
LA English
DT Article
AB Several computing platforms were evaluated with the MCNP4B Monte Carlo radiation transport code. The DEC AlphaStation 500/500 was the fastest to run MCNP4B. Compared to the HP 9000-735, the fastest platform 4 yr ago, the AlphaStation is 335% faster the HP C180 is 133% faster the SGI Origin 2000 is 82% faster the Sun UltraSparc-1 200E is 54% faster the Micron Millennia Pro personal computer is 10% faster; the Gray T94/4128 is 1% faster the IBM RS/6000-590 is 93% as fast, the DEC 3000/600 is 81% as fast, the Sim Sparc20 is 57% as fast, the Gray YMP 8/8128 is 57% as fast, the Sun Sparc5 is 33% as fast, and the Sun Sparc2 is 13% as fast. All results presented are reproducible and allow for comparison to computer platforms not included in this study. Timing studies are seen to be very problem dependent. The performance gains resulting from advances in software were also investigated. Various compilers and operating systems were seen to have a modest impact on performance, whereas hardware improvements have resulted in a factor of 4 improvement. MCNP4B also ran approximately as fast as MCNP4A.
C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, XTM, Los Alamos, NM 87545 USA.
RP McLaughlin, HE (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, XTM, MS B226, Los Alamos, NM 87545 USA.
NR 12
TC 2
Z9 2
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 JUL
PY 1998
VL 129
IS 3
BP 311
EP 319
PG 9
WC Nuclear Science & Technology
SC Nuclear Science & Technology
GA 102LX
UT WOS:000074926800009
ER
PT J
AU Bandini, BR
Ivanov, KN
Baratta, AJ
Steinke, RG
AF Bandini, BR
Ivanov, KN
Baratta, AJ
Steinke, RG
TI Verification of a three-dimensional nodal transient neutronics routine
for the TRAC-PF1/MOD3 thermal-hydraulic system analysis code
SO NUCLEAR TECHNOLOGY
LA English
DT Article
AB The verification of a three-dimensional nodal transient neutronics routine in the TRAC-PF1/MOD3 Version 1.0 thermal-hydraulic system analysis computer code is discussed. This neutronics algorithm is based on a fully implicit transient version of the well-known nodal expansion method Results from running; TRAC-PF1/MOD3 with this new neutronics routine were compared with the results of running two established neutronics/thermal-hydraulic space-time codes, HERMITE and ARROTTA. The transient chosen for this code verification was a rapid ejection of an off-center control rod in a: Westinghouse pressurized water reactor which is initially at hot standby This severe prompt-critical transient provides a stringent test of TRAC-PF1/MOD3's new multidimensional neutronics routine and its coupling to the existing thermal-hydraulic solution methodology. Because of its speed, the transient tests only the fuel rod heat conduction coupling and nor the coolant thermal-hydraulic coupling.
Acceptable agreement was obtained among the results from TRAC-PF1/MOD3, HERMITE, and ARROTTA during all phases of this transient. Agreement was in the areas of time dependence of total-core and peak-assembly powers, as well as the time dependence of the core-average and peak-assembly fuel temperatures. In addition, comparison of several steady-state calculations that provide initial conditions for the transient analysis showed acceptable agreement in the calculated eigenvalues and normalized assembly-power distributions.
C1 Bettis Atom Power Lab, W Mifflin, PA 15122 USA.
Penn State Univ, Dept Nucl Engn, University Pk, PA 16802 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
RP Bandini, BR (reprint author), Bettis Atom Power Lab, POB 79, W Mifflin, PA 15122 USA.
NR 13
TC 1
Z9 1
U1 0
U2 0
PU AMER NUCLEAR SOCIETY
PI LA GRANGE PK
PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA
SN 0029-5450
J9 NUCL TECHNOL
JI Nucl. Technol.
PD JUL
PY 1998
VL 123
IS 1
BP 1
EP 20
PG 20
WC Nuclear Science & Technology
SC Nuclear Science & Technology
GA ZY932
UT WOS:000074677400001
ER
PT J
AU Sargent, TN
Overcamp, TJ
Bickford, DF
Cicero-Herman, CA
AF Sargent, TN
Overcamp, TJ
Bickford, DF
Cicero-Herman, CA
TI Vitrification of cesium-laden organic ion-exchange resin in a stirred
melter
SO NUCLEAR TECHNOLOGY
LA English
DT Article
AB Tests were conducted using a stirred-tank melter to vitrify nonradioactive, cesium-laden organic ion-exchange resin. This resin, which is highly effective in removing cesium from solution, was developed to replace the complex sodium tetraphenylborate precipitation process used at the Defense Waste Processing Facility at the Savannah River Site to remove Cs-137 from a wastewater solution. The glass produced had a Fe2+/Fe-Total ratio that was acceptable for high-level waste glass. No damage to the melter was observed. Lower-bound estimates of overall cesium retention in the glass range from 70.5 to 73.9%. Only, 2.1 to 4.3% of the cesium was emitted from the melter Because between 21.8 and 27.4% of the cesium was not recovered, the overall cesium retention may have been substantially higher.
C1 Clemson Univ, Anderson, SC 29625 USA.
Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA.
RP Sargent, TN (reprint author), Clemson Univ, 342 Comp Court, Anderson, SC 29625 USA.
NR 8
TC 2
Z9 2
U1 0
U2 0
PU AMER NUCLEAR SOCIETY
PI LA GRANGE PK
PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA
SN 0029-5450
J9 NUCL TECHNOL
JI Nucl. Technol.
PD JUL
PY 1998
VL 123
IS 1
BP 60
EP 66
PG 7
WC Nuclear Science & Technology
SC Nuclear Science & Technology
GA ZY932
UT WOS:000074677400005
ER
PT J
AU McGrail, BP
AF McGrail, BP
TI Analytical solutions for diffusive mass transport from a sphere,
considering a surface flux boundary condition
SO NUCLEAR TECHNOLOGY
LA English
DT Article
ID RADIONUCLIDE; MIGRATION; MATRIX
AB Analytical solutions to the unsteady diffusion equation in spherical geometry are presented for uniform and composite porous media. In this case, a Neumann (prescribed flux) boundary condition is assumed as opposed to a Dirichlet (prescribed concentration) boundary condition used in previously published derivations. For radionuclides that have very high solubility under a given set of geochemical conditions, such as Tc-99 and Se-79 Under oxidizing conditions, a prescribed flux boundary condition is more appropriate.
C1 Pacific NW Natl Lab, Appl Geol & Geochem Dept, Richland, WA 99352 USA.
RP McGrail, BP (reprint author), Pacific NW Natl Lab, Appl Geol & Geochem Dept, POB 999, Richland, WA 99352 USA.
NR 9
TC 1
Z9 1
U1 0
U2 0
PU AMER NUCLEAR SOCIETY
PI LA GRANGE PK
PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA
SN 0029-5450
J9 NUCL TECHNOL
JI Nucl. Technol.
PD JUL
PY 1998
VL 123
IS 1
BP 82
EP 89
PG 8
WC Nuclear Science & Technology
SC Nuclear Science & Technology
GA ZY932
UT WOS:000074677400007
ER
PT J
AU Dulloo, AR
Ruddy, FH
Congedo, TV
Seidel, JG
Gehrke, RJ
AF Dulloo, AR
Ruddy, FH
Congedo, TV
Seidel, JG
Gehrke, RJ
TI Detection limits of a laboratory pulsed gamma neutron activation
analysis system for the nondestructive assay of mercury, cadmium, and
lead
SO NUCLEAR TECHNOLOGY
LA English
DT Article
AB Detection of Hg, Cd, and Pb within concrete matrices located in 8-gal drums was successfully demonstrated using a pulsed gamma neutron activation analysis system. Real-time assays of 600 s led to the detection of these metals at concentration levels ranging, in parts per million (ppm) by weight, from 487 to 19 820 for Hg, 485 to 8181 for Cd, and 9927 to 19 950 for Pb. The measurements of Hg and Cd relied on the observation of thermal neutron-induced prompt gamma rays, whereas the Pb measurements relied on the observation of decay gamma rays from Pb-207m, a product of fast neutron-induced reactions in Pb. The projected bower limits of detection of the current system for a 600-s run are 15, 170, and 8600 ppm for Cd Hg, and Pb, respectively. Up to a one-order magnitude of improvement in sensitivity is anticipated through the enhancement of the system's detector and neutron source. The results obtained confirm the potential of prompt and decay gamma neutron activation analysis as an effective method for the nondestructive analysis of hazardous metals in mixed-waste drums.
C1 Westinghouse Elect Co, Ctr Sci & Technol, Pittsburgh, PA 15235 USA.
Lockheed Martin Idaho Technol, Idaho Falls, ID 83415 USA.
RP Dulloo, AR (reprint author), Westinghouse Elect Co, Ctr Sci & Technol, 1310 Beulah Rd, Pittsburgh, PA 15235 USA.
NR 6
TC 12
Z9 12
U1 0
U2 1
PU AMER NUCLEAR SOCIETY
PI LA GRANGE PK
PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA
SN 0029-5450
J9 NUCL TECHNOL
JI Nucl. Technol.
PD JUL
PY 1998
VL 123
IS 1
BP 103
EP 112
PG 10
WC Nuclear Science & Technology
SC Nuclear Science & Technology
GA ZY932
UT WOS:000074677400009
ER
PT J
AU Brown, FC
Heald, SM
Brewe, DL
Jiang, DT
AF Brown, FC
Heald, SM
Brewe, DL
Jiang, DT
TI Point defect production by X-rays above and below the bromine K-edge in
KBr
SO NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA D-CONDENSED MATTER ATOMIC
MOLECULAR AND CHEMICAL PHYSICS FLUIDS PLASMAS BIOPHYSICS
LA English
DT Article
ID F-CENTER FORMATION; ALKALI-HALIDES; EXCITATION; CRYSTALS
AB F-center formation by monochromatic X-rays has been studied above and below the bromine K-edge in single crystals of KBr at 77 K. A concentrated beam from an undulator at the Advanced Photon Source was used to produce these point defects, which were detected by a sensitive laser-induced luminescence method. Experiments were carried out over an especially wide range of monochromatic X-ray intensity. Contrary to our previous reports, a large increase in F-center formation efficiency was not found upon crossing the bromine K-edge, which suggests that additional Auger-cascade mechanisms do not compete strongly with the usual multiple ionization electron-hole recombination processes known to generate point defects.
C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA.
Argonne Natl Lab, Adv Photon Source, Pacific NW Lab, Argonne, IL 60439 USA.
Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada.
RP Brown, FC (reprint author), Univ Washington, Dept Phys, Box 351560, Seattle, WA 98195 USA.
NR 12
TC 1
Z9 1
U1 0
U2 0
PU EDITRICE COMPOSITORI BOLOGNA
PI BOLOGNA
PA VIA STALINGRADO 97/2, I-40128 BOLOGNA, ITALY
SN 0392-6737
J9 NUOVO CIMENTO D
JI Nuovo Cimento Soc. Ital. Fis. D-Condens. Matter At. Mol. Chem. Phys.
Fluids Plasmas Biophys.
PD JUL-AUG
PY 1998
VL 20
IS 7-8
BP 853
EP 858
PG 6
WC Physics, Multidisciplinary
SC Physics
GA 132GL
UT WOS:000076621900002
ER
PT J
AU Goldberg, L
Koplow, JP
Moeller, RP
Kliner, DAV
AF Goldberg, L
Koplow, JP
Moeller, RP
Kliner, DAV
TI High-power superfluorescent source with a side-pumped Yb-doped
double-cladding fiber
SO OPTICS LETTERS
LA English
DT Article
ID AMPLIFIER
AB A compact superfluorescent source based on an Yb-doped double-cladding fiber amplifier is described. The packaged amplifier is pumped at 975 nm by side-coupling emission from a 2.0-W broad-stripe laser diode through an imbedded V groove. The fiber source generates 485 mW of broadband emission centered at 1055 nm with a 41-nm FWHM flat power spectrum. OCIS codes: 160.6630, 160.3510, 140.4480, 060.2380, 060.2320, 060.2310.
C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA.
Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA.
RP Goldberg, L (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA.
NR 14
TC 49
Z9 54
U1 1
U2 4
PU OPTICAL SOC AMER
PI WASHINGTON
PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA
SN 0146-9592
J9 OPT LETT
JI Opt. Lett.
PD JUL 1
PY 1998
VL 23
IS 13
BP 1037
EP 1039
DI 10.1364/OL.23.001037
PG 3
WC Optics
SC Optics
GA ZY167
UT WOS:000074593000019
PM 18087421
ER
PT J
AU Fittinghoff, DN
Squier, JA
Barty, CPJ
Sweetser, JN
Trebino, R
Muller, M
AF Fittinghoff, DN
Squier, JA
Barty, CPJ
Sweetser, JN
Trebino, R
Muller, M
TI Collinear type II second-harmonic-generation frequency-resolved optical
gating for use with high-numerical-aperture objectives
SO OPTICS LETTERS
LA English
DT Article
AB Ultrashort-pulse lasers are now commonly used for multiphoton microscopy, and optimizing the performance of such systems requires careful characterization of the pulses at the tight focus of the microscope objective. We solve this problem by use of a collinear geometry in frequency-resolved optical gating that uses type II second-harmonic generation and that allows the full N.A. of the microscope objective to be used. We then demonstrate the technique by measuring the intensity and the phase of a 22-fs pulse focused by a 20x, 0.4-N.A. air objective. (C) 1998 Optical Society of America OCIS codes: 140.7090,320.7100, 320.7160.
C1 Univ Calif San Diego, Inst Nonlinear Sci, La Jolla, CA 92093 USA.
Univ Calif San Diego, Dept Elect Engn & Comp Sci, La Jolla, CA 92093 USA.
Sandia Natl Labs, Livermore, CA 94551 USA.
BioCetrum Amsterdam, Inst Mol Cell Biol, NL-1098 SM Amsterdam, Netherlands.
RP Fittinghoff, DN (reprint author), Univ Calif San Diego, Inst Nonlinear Sci, La Jolla, CA 92093 USA.
NR 7
TC 45
Z9 45
U1 0
U2 6
PU OPTICAL SOC AMER
PI WASHINGTON
PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA
SN 0146-9592
J9 OPT LETT
JI Opt. Lett.
PD JUL 1
PY 1998
VL 23
IS 13
BP 1046
EP 1048
DI 10.1364/OL.23.001046
PG 3
WC Optics
SC Optics
GA ZY167
UT WOS:000074593000022
PM 18087424
ER
PT J
AU Viano, AM
Majzoub, EH
Stroud, RM
Kramer, MJ
Misture, ST
Gibbons, PC
Kelton, KF
AF Viano, AM
Majzoub, EH
Stroud, RM
Kramer, MJ
Misture, ST
Gibbons, PC
Kelton, KF
TI Hydrogen absorption and storage in quasicrystalline and related Ti-Zr-Ni
alloys
SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS
AND MECHANICAL PROPERTIES
LA English
DT Article
ID PHASE
AB Detailed studies of the absorption and storage of hydrogen by icosahedral quasicrystalline Ti-Zr-Ni are presented. Two different absorption methods, one at room temperature and another requiring elevated temperatures, successfully introduce hydrogen into Ti-Zr-Ni alloys. Absorption is accompanied by an expansion of the quasilattice, and results correlating the rate of expansion to the hydrogen concentration are presented. The absorption rates suggest that a surface oxide layer acts as a barrier to hydrogen absorption and this is confirmed by surface depth profiling studies made with scanning Auger spectroscopy. Desorption studies also indicate some hydrogen cycling ability for the quasicrystal. The hydrogen storage ability of the quasicrystal is compared to, and found to be better than, those of the related phases in this system.
C1 Washington Univ, Dept Phys, St Louis, MO 63130 USA.
Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA.
Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
RP Viano, AM (reprint author), Rhodes Coll, Dept Phys, Memphis, TN 38112 USA.
RI Stroud, Rhonda/C-5503-2008
OI Stroud, Rhonda/0000-0001-5242-8015
NR 20
TC 71
Z9 72
U1 1
U2 3
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 JUL
PY 1998
VL 78
IS 1
BP 131
EP 141
PG 11
WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical
Engineering; Physics, Applied; Physics, Condensed Matter
SC Materials Science; Metallurgy & Metallurgical Engineering; Physics
GA ZU426
UT WOS:000074195900006
ER
PT J
AU Jin, Z
Gray, GT
Yamaguchi, M
AF Jin, Z
Gray, GT
Yamaguchi, M
TI Mechanical twinning in a 45 degrees ((3)over-bar-21) oriented
polysynthetically twinned TiAl crystal at a high strain rate and a high
temperature
SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS
AND MECHANICAL PROPERTIES
LA English
DT Article
ID ROOM-TEMPERATURE; DEFORMATION STRUCTURES; PLASTIC-DEFORMATION;
INTERSECTIONS; BEHAVIOR; ALLOYS; STRESS; AL
AB Mechanical twinning behaviour in a 45 degrees [<(3)over bar 21>] oriented (the lamellar interface was tilted 45 degrees from the loading axis about the [<(3)over bar 21>] direction in the lamellar interface) polysynthetically twinned crystal deformed in compression at a strain rate of 3000 s(-1) and a temperature of 800 degrees C was characterized. (111) [11(2) over bar] parallel twinning was observed to be the dominant deformation mode in domains [III] and [IV] where the transmission electron microscopy foil normals were close to [10(1) over bar] and [1(1) over bar 0] respectively. Cross-twinning of the (<(1)over bar 11>) [(1) over bar 1 (2) over bar], (1(1) over bar 1) [1 (1) over bar (2) over bar] and (111) [112] variants in the remaining domains was found to be a complementary deformation mode to accommodate deformation. The mechanical twin propagation stress was found to be less than 150 MPa at 3000s(-1) and 800 degrees C in TiAl. Mechanical twin propagation was found to respond to the global sample stress state and thus the crystal yield and Bow stresses. When mechanical twinning was the dominant deformation mode in a domain, it was observed to obey Schmid's law.
C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA.
Kyoto Univ, Dept Met Sci & Technol, Sakyo Ku, Kyoto 606, Japan.
RP Jin, Z (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA.
NR 31
TC 10
Z9 11
U1 1
U2 8
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 JUL
PY 1998
VL 78
IS 1
BP 239
EP 253
PG 15
WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical
Engineering; Physics, Applied; Physics, Condensed Matter
SC Materials Science; Metallurgy & Metallurgical Engineering; Physics
GA ZU426
UT WOS:000074195900013
ER
PT J
AU Jones, ED
Millunchick, JM
Follstaedt, D
Lee, S
Reno, J
Twesten, RD
Zhang, Y
Mascarenhas, A
AF Jones, ED
Millunchick, JM
Follstaedt, D
Lee, S
Reno, J
Twesten, RD
Zhang, Y
Mascarenhas, A
TI Detection of lateral composition modulation by magnetoexciton
spectroscopy
SO PHYSICA E
LA English
DT Article; Proceedings Paper
CT 8th International Conference on Modulated Semiconductor Structures
CY JUL 14-18, 1997
CL UNIV CA, SANTA BARBARA, CALIFORNIA
HO UNIV CA
DE composition modulation; photoluminescence; magnetoexciton; quantum wires
ID QUANTUM-WIRE HETEROSTRUCTURES; SUPERLATTICES; GROWTH
AB An experimental signature for detecting spontaneous lateral composition modulation in a (InAs)(n)/(GaAs)(m) short period superlattice on a InP substrate based on magnetoexciton spectroscopy is described. We find by aligning the magnetic field in three crystallographic directions, one parallel to and the other two perpendicular to the composition modulation direction, that the magnetoexciton shifts are anisotropic and are a good indicator for the presence of composition modulation. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Sandia Natl Labs, Albuquerque, NM 87185 USA.
Natl Renewable Energy Lab, Golden, CO USA.
RP Jones, ED (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA.
NR 11
TC 3
Z9 3
U1 0
U2 1
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 1386-9477
J9 PHYSICA E
JI Physica E
PD JUL
PY 1998
VL 2
IS 1-4
BP 44
EP 48
DI 10.1016/S1386-9477(98)00011-3
PG 5
WC Nanoscience & Nanotechnology; Physics, Condensed Matter
SC Science & Technology - Other Topics; Physics
GA 110LT
UT WOS:000075383500010
ER
PT J
AU Jones, ED
Tozer, SW
Schmiedel, T
AF Jones, ED
Tozer, SW
Schmiedel, T
TI Pressure dependence of the band-gap energy and the conduction-band mass
for an n-type InGaAs/GaAs strained single-quantum well
SO PHYSICA E
LA English
DT Article; Proceedings Paper
CT 8th International Conference on Modulated Semiconductor Structures
CY JUL 14-18, 1997
CL UNIV CA, SANTA BARBARA, CALIFORNIA
HO UNIV CA
DE magnetoluminescence; pressure; quantum well; strain
ID MAGNETOLUMINESCENCE
AB We report the measurement of the pressure dependence for the band-gap energy E-g and conduction-band mass m(c) for an 80 Angstrom-wide n-type In0.20Ga0.80As/GaAs strained-single-quantum well at 4.2 K for pressures between 0 and 35 kbar and fields up to 30 T. The band-gap energy E-g, at each pressure, was determined by extrapolating the magnetoluminescence "fan-diagram" to zero magnetic field. The pressure dependence of the band-gap energy was found to be quadratic with a linear term of about 10.3 meV/kbar and a small, -2 x 10(-2) mev/kbar(2), quadratic contribution. Analyses of the pressure-dependent 4.2 K magnetoluminescence data yield a conduction-band mass logarithmic pressure derivative delta log(m(c))/delta P = 0.58% kbar(-1). (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Sandia Natl Labs, Albuquerque, NM 87185 USA.
Natl High Magnet Field Lab, Tallahassee, FL USA.
RP Jones, ED (reprint author), Sandia Natl Labs, POB 4800, Albuquerque, NM 87185 USA.
NR 12
TC 4
Z9 4
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 1386-9477
J9 PHYSICA E
JI Physica E
PD JUL
PY 1998
VL 2
IS 1-4
BP 146
EP 150
DI 10.1016/S1386-9477(98)00032-0
PG 5
WC Nanoscience & Nanotechnology; Physics, Condensed Matter
SC Science & Technology - Other Topics; Physics
GA 110LT
UT WOS:000075383500031
ER
PT J
AU Silveira, E
Dondl, W
Abstreiter, G
Haller, EE
AF Silveira, E
Dondl, W
Abstreiter, G
Haller, EE
TI Raman scattering in annealed isotopic (Ge-70)(n)(Ge-74)(m) superlattices
SO PHYSICA E
LA English
DT Article; Proceedings Paper
CT 8th International Conference on Modulated Semiconductor Structures
CY JUL 14-18, 1997
CL UNIV CA, SANTA BARBARA, CALIFORNIA
HO UNIV CA
DE self-diffusion; Raman scattering; isotopic superlattices
ID SELF-DIFFUSION; GERMANIUM
AB Raman scattering by optical phonons is used to study the interface intermixing in isotopic (Ge-70)(n)(Ge-74)(m) thin superlattices, with n and rn equal to 8, 12, 16 and 24 atomic monolayers, for annealling at 500 degrees C and various times. The experimental results compares very well with theoretical calculations within the planar force constant model and the bond polarizability approach. The diffusion is simulated by a combination of the virtual crystal approximation and the solution of the Fick's diffusion equation for the superlattice geometry. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Tech Univ Munich, Walter Schottky Inst, D-85748 Garching, Germany.
Univ Calif Berkeley, Berkeley, CA 94720 USA.
Lawrence Berkeley Lab, Berkeley, CA 94720 USA.
RP Silveira, E (reprint author), Tech Univ Munich, Walter Schottky Inst, Coulombwall, D-85748 Garching, Germany.
EM silveira@wsi.tu-muenchen.de
NR 5
TC 1
Z9 2
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 1386-9477
J9 PHYSICA E
JI Physica E
PD JUL
PY 1998
VL 2
IS 1-4
BP 291
EP 294
DI 10.1016/S1386-9477(98)00061-7
PG 4
WC Nanoscience & Nanotechnology; Physics, Condensed Matter
SC Science & Technology - Other Topics; Physics
GA 110LT
UT WOS:000075383500061
ER
PT J
AU Follstaedt, DM
Twesten, RD
Millunchick, JM
Lee, SR
Jones, ED
Ahrenkiel, SP
Zhang, Y
Mascarenhas, A
AF Follstaedt, DM
Twesten, RD
Millunchick, JM
Lee, SR
Jones, ED
Ahrenkiel, SP
Zhang, Y
Mascarenhas, A
TI Spontaneous lateral composition modulation in InAlAs and InGaAs
short-period superlattices
SO PHYSICA E
LA English
DT Article; Proceedings Paper
CT 8th International Conference on Modulated Semiconductor Structures
CY JUL 14-18, 1997
CL UNIV CA, SANTA BARBARA, CALIFORNIA
HO UNIV CA
DE lateral composition modulation; InAlAs; InGaAs; strain; short-period
superlattice
ID GROWTH
AB The microstructure of spontaneous lateral composition modulation along the [1 1 0] direction has been studied in (InAs)(n)/(AlAs)(m) short-period superlattices grown by molecular beam epitaxy on (0 0 1) InP. X-ray diffraction and transmission electron microscopy show that global strain (epsilon) in the superlattice reduces the degree of composition modulation, which disappears for /epsilon/ > 0.7%. For tensile strains of epsilon approximate to + 0.4%, we find that In-rich columns become regularly spaced and correlated with cusps in the growth surface. A similar correlation is seen in (InAs)(n)/(GaAs)(m) short-period superlattices between the enriched columns and the peaks and valleys of {1 1 4}(A) facets on the surface. The enriched columns in the (InAs)(n)/(GaAs)(m) layer land the facets) extend for much longer distances(similar to 0.2-0.4 mu m) in the [1 (1) over bar 0] direction than do the columns in the (InAs)(n)/(AlAs)(m) layer (similar to 56 nm). (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Sandia Natl Labs, Albuquerque, NM 87185 USA.
Natl Renewable Energy Lab, Golden, CO 80401 USA.
RP Follstaedt, DM (reprint author), Sandia Natl Labs, Mail Stop 1056, Albuquerque, NM 87185 USA.
NR 9
TC 12
Z9 12
U1 0
U2 2
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 1386-9477
J9 PHYSICA E
JI Physica E
PD JUL
PY 1998
VL 2
IS 1-4
BP 325
EP 329
DI 10.1016/S1386-9477(98)00068-X
PG 5
WC Nanoscience & Nanotechnology; Physics, Condensed Matter
SC Science & Technology - Other Topics; Physics
GA 110LT
UT WOS:000075383500068
ER
PT J
AU Rydberg, B
Lobrich, M
Cooper, PK
AF Rydberg, B
Lobrich, M
Cooper, PK
TI Repair of clustered DNA damage caused by high LET radiation in human
fibroblasts
SO PHYSICA MEDICA
LA English
DT Article
DE DNA damage; DNA double-strand breaks; DNA repair; ionizing radiation
ID DOUBLE-STRAND BREAKS; FIELD GEL-ELECTROPHORESIS; HIGH-ENERGY NEON;
IONIZING-RADIATION; IRON IONS; FRAGMENTS; MECHANISMS; CELLS
AB It has recently been demonstrated experimentally that DNA damage induced by high LET radiation in mammalian cells is non-randomly distributed along the DNA molecule in the form of clusters of various sizes. The sizes of such clusters range from a few base-pairs to at least 200 kilobase-pairs. The high biological efficiency of high LET radiation for induction of relevant biological endpoints is probably a consequence of this clustering, although the exact mechanisms by which the clustering affects the biological outcome is not known. We discuss here results for induction and repair of base damage, single-strand breaks and double-strand breaks for low and high LET radiations. These results are discussed in the context of clustering. Of particular interest is to determine how clustering at different scales affects overall rejoining and fidelity of rejoining of DNA double-strand breaks. However, existing methods for measuring repair of DNA strand breaks are unable to resolve breaks that are close together in a cluster. This causes problems in interpretation of current results from high LET radiation and will require new methods to be developed.
C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA.
FU NIDCR NIH HHS [DE-AC03-76SF00098]
NR 18
TC 8
Z9 8
U1 0
U2 0
PU GIARDINI EDITORI S A LUGANO
PI LUGANO
PA PIAZZA MONTE CENERI 13,, CH6901 LUGANO, SWITZERLAND
SN 1120-1797
J9 PHYS MEDICA
JI Phys. Medica
PD JUL
PY 1998
VL 14
SU 1
BP 24
EP 28
PG 5
WC Radiology, Nuclear Medicine & Medical Imaging
SC Radiology, Nuclear Medicine & Medical Imaging
GA 135QF
UT WOS:000076813600004
PM 11542637
ER
PT J
AU Batinic, M
Dadic, I
Slaus, I
Svarc, A
Nefkens, BMK
Lee, TSH
AF Batinic, M
Dadic, I
Slaus, I
Svarc, A
Nefkens, BMK
Lee, TSH
TI The new determination of the eta N S-wave scattering length from a
three-channel, multi-resonance amplitude analysis
SO PHYSICA SCRIPTA
LA English
DT Article
ID MODEL
AB A three-channel multi-resonance, unitary model developed in 1995 is used to determine the pi N --> eta N and eta N --> eta N amplitudes by re-analyzing the available data on pi N elastic scattering and the weighted data for the pi N --> eta N total and differential cross sections. The input pi N elastic scattering amplitude in the S-11 channel has been improved, following suggestions of G. Hohler. Our new result of eta N scattering length, a(eta N) = (0.717 +/- 0.030) + i . (0.263 +/- 0.025) fm, suggests that the eta d system is unbound or loosely bound.
C1 Rudjer Boskovic Inst, Zagreb, Croatia.
Univ Calif Los Angeles, Los Angeles, CA USA.
Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA.
RP Batinic, M (reprint author), Rudjer Boskovic Inst, Zagreb, Croatia.
NR 17
TC 60
Z9 60
U1 0
U2 2
PU ROYAL SWEDISH ACAD SCIENCES
PI STOCKHOLM
PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN
SN 0281-1847
J9 PHYS SCRIPTA
JI Phys. Scr.
PD JUL
PY 1998
VL 58
IS 1
BP 15
EP 18
DI 10.1088/0031-8949/58/1/002
PG 4
WC Physics, Multidisciplinary
SC Physics
GA 100EQ
UT WOS:000074802600003
ER
PT J
AU Lopez-Urrutia, JRC
Beiersdorfer, P
Savin, DW
Widmann, K
AF Lopez-Urrutia, JRC
Beiersdorfer, P
Savin, DW
Widmann, K
TI Precision measurement of the lifetime of the 1s2s S-3(1) metastable
level in heliumlike O6+
SO PHYSICAL REVIEW A
LA English
DT Article
ID BEAM ION-TRAP; RADIATIVE LIFETIME; TEMPERATURE; DIAGNOSTICS; PLASMAS;
DENSITY; STATE
AB The lifetime of the 1s2s S-3(1) level of the He-like O6+ ion has been measured using the Electron Beam Ion Trap in the magnetic trapping mode. A value of 956(-4)(+5): ps is found, which corresponds to a radiative transition rate of 1046(-5)(+4) s(-1) for the magnetic dipole transition to the 1s(2) S-1(0) ground state. This value is in excellent agreement with recent theoretical predictions and distinguishes among different treatments of negative energy states and correlation in multiconfiguration Dirac-Fock calculations.
C1 Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA.
Columbia Univ, Dept Phys, New York, NY 10025 USA.
Columbia Univ, Columbia Astrophys Lab, New York, NY 10025 USA.
RP Lopez-Urrutia, JRC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA.
RI Savin, Daniel/B-9576-2012; Crespo Lopez-Urrutia, Jose R./F-7069-2011
OI Savin, Daniel/0000-0002-1111-6610; Crespo Lopez-Urrutia, Jose
R./0000-0002-2937-8037
NR 19
TC 32
Z9 32
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 JUL
PY 1998
VL 58
IS 1
BP 238
EP 241
PG 4
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500036
ER
PT J
AU Huang, SW
Goodson, DZ
Lopez-Cabrera, M
Germann, TC
AF Huang, SW
Goodson, DZ
Lopez-Cabrera, M
Germann, TC
TI Large-order dimensional perturbation theory for diatomic molecules
within the Born-Oppenheimer approximation
SO PHYSICAL REVIEW A
LA English
DT Article
ID GROUND-STATE ENERGY; VARIABLE DIMENSIONALITY; 1/D EXPANSION; LIMIT;
SERIES; ATOMS; H-2+; H2+; RENORMALIZATION; 1/N-EXPANSION
AB A renormalization of the D-dimensional Hamiltonian is developed to ensure that the large-D limit corresponds to a single well at any value of the internuclear distance R. This avoids convergence problems caused by a symmetry-breaking transition that is otherwise expected to occur when R is approximately equal to the equilibrium bond distance R(eq), With larger R giving a double well. This symmetry breaking has restricted the applicability of large-order perturbation theory in 1/D to cases where R is significantly less than R(eq). The renormalization greatly extends the range of R for which the large-order expansion can be summed. A numerical demonstration is presented for H(2)(+). The 1/D expansions are summed using Pade-Borel approximants with modifications that explicitly model known singularity structure.
C1 So Methodist Univ, Dept Chem, Dallas, TX 75275 USA.
Harvard Univ, Dept Chem, Cambridge, MA 02138 USA.
Los Alamos Natl Lab, Theoret Div T11, Los Alamos, NM 87545 USA.
RP Huang, SW (reprint author), So Methodist Univ, Dept Chem, Dallas, TX 75275 USA.
NR 50
TC 6
Z9 6
U1 2
U2 4
PU AMER PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 1050-2947
J9 PHYS REV A
JI Phys. Rev. A
PD JUL
PY 1998
VL 58
IS 1
BP 250
EP 257
DI 10.1103/PhysRevA.58.250
PG 8
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500038
ER
PT J
AU Djuric, N
Zhou, S
Dunn, GH
Bannister, ME
AF Djuric, N
Zhou, S
Dunn, GH
Bannister, ME
TI Electron-impact dissociative excitation of CDn+ (n=2-5): Detection of
light fragment ions D+ and D-2(+)
SO PHYSICAL REVIEW A
LA English
DT Article
ID BEAM
AB Absolute cross sections are reported for the electron-impact dissociative excitation of the deuterated hydrocarbon ions CDn+ (n=2-5) from threshold to 70 eV using a crossed beams technique. The method focuses on detecting and measuring Light dissociation-product ions from a heavy target. The ion targets are typical of those formed in the discharge ion source, and some may be in excited electronic and/or vibrational states. A common feature of the studied targets was a dominant D+ formation cross section with almost the same absolute value of 2 x 10(-16) cm(2) for all n from 25 to 70 eV. The present measurements are compared with the available data, and for D+ from CD2+ and CD5+ the data agree well with recent results obtained with the storage-ring technique.
C1 Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA.
Natl Inst Stand & Technol, Boulder, CO 80309 USA.
Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA.
RP Djuric, N (reprint author), Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA.
OI Bannister, Mark E./0000-0002-9572-8154
NR 20
TC 16
Z9 16
U1 0
U2 0
PU AMERICAN PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 1050-2947
J9 PHYS REV A
JI Phys. Rev. A
PD JUL
PY 1998
VL 58
IS 1
BP 304
EP 308
DI 10.1103/PhysRevA.58.304
PG 5
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500044
ER
PT J
AU Isaacs, WA
McCurdy, CW
Rescigno, TN
AF Isaacs, WA
McCurdy, CW
Rescigno, TN
TI Theoretical support for a Ramsauer-Townsend minimum in electron-CF4
scattering
SO PHYSICAL REVIEW A
LA English
DT Article
ID EFFECTIVE POTENTIAL METHODS; LOW-ENERGY ELECTRONS; CROSS-SECTIONS;
VARIATIONAL TREATMENTS; MOLECULE COLLISIONS; CF4; ABINITIO;
HALOMETHANES; CCL2F2; CCL3F
AB We describe complex Kohn calculations for elastic e(-)-CF4, scattering at incident electron energies of 0.04-20 eV. An accurate representation of the electronic correlation effects involving target polarization is critical in the explicit demonstration of a Ramsauer-Townsend minimum. We use a set of polarized virtual orbitals to form a compact representation of closed channels in the trial scattering function to include these effects. These are the first ab initio calculations to verify the Ramsauer-Townsend minimum in CF4. We find excellent comparison between the complex Kohn results and measured differential and integral cross sections.
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 22
TC 23
Z9 23
U1 0
U2 6
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 JUL
PY 1998
VL 58
IS 1
BP 309
EP 313
DI 10.1103/PhysRevA.58.309
PG 5
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500045
ER
PT J
AU Macek, JH
Cavagnero, MJ
AF Macek, JH
Cavagnero, MJ
TI Demkov-Osherov model reformulated in terms of conventional scattering
theory
SO PHYSICAL REVIEW A
LA English
DT Article
ID STURMIAN EXPANSION; GREEN-FUNCTION; IONIZATION; THRESHOLD; HYDROGEN
AB One of the few exactly solvable time-dependent quantum-mechanics problems was first analyzed by Demkov and Osherov 30 years ago (Zh. Eksp. Teor. Fit. 53, 1589 (1967) [Sov. Phys. JETP 26, 916 (1968)]). This model problem describes the interaction of a set of approximate stationary states with an additional state whose energy, in zeroth approximation, is a linear function of time. The Demkov-Osherov model is reexamined here using conventional Fourier transform methods. Emphasis on forward propagation in time eliminates the need for a Laplace transform of the wave function, as well as the resultant choice of contours for the evaluation of transition amplitudes. The evolution operator for the model Hamiltonian is expressed in terms of a single, frequency-dependent Sturmian. Such Sturmian functions are of considerable current interest in the analysis of nonadiabatic phenomena.
C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA.
Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA.
Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA.
RP Macek, JH (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA.
NR 14
TC 12
Z9 12
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 JUL
PY 1998
VL 58
IS 1
BP 348
EP 356
DI 10.1103/PhysRevA.58.348
PG 9
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500049
ER
PT J
AU Guo, DS
Freeman, RR
Wu, YS
AF Guo, DS
Freeman, RR
Wu, YS
TI Schrodinger-like equation for a nonrelativistic electron in a photon
field of arbitrary intensity
SO PHYSICAL REVIEW A
LA English
DT Article
ID QUANTIZED RADIATION-FIELD; MULTIPHOTON IONIZATION; STATIONARY SOLUTIONS;
LASER FIELD
AB The Schrodinger equation with minimal coupling for a nonrelativistic electron interacting with a single-mode photon field is not satisfied by the nonrelativistic limit of the exact solutions to the corresponding Dirac equation. A Schrodinger-like equation valid for arbitrary photon intensity is derived from the Dirac equation without the weak-field assumption. The "eigenvalue" in the present equation is an operator in a Cartan subalgebra. An approximation consistent with the nonrelativistic energy level derived from its relativistic value replaces the eigenvalue operator by an ordinary number, recovering the Schrodinger eigenvalue equation used in the formal scattering formalism. The Schrodinger-like equation for the multimode case is also presented.
C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA.
Inst Adv Study, Princeton, NJ 08540 USA.
So Univ & A&M Coll, Dept Phys, Baton Rouge, LA 70813 USA.
RP Guo, DS (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA.
NR 15
TC 14
Z9 14
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 JUL
PY 1998
VL 58
IS 1
BP 521
EP 525
DI 10.1103/PhysRevA.58.521
PG 5
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500068
ER
PT J
AU White, AG
Mitchell, JR
Nairz, O
Kwiat, PG
AF White, AG
Mitchell, JR
Nairz, O
Kwiat, PG
TI "Interaction-free" imaging
SO PHYSICAL REVIEW A
LA English
DT Article
AB Using the complementary wavelike and particlelike natures of photons, it is possible to make "interaction-free" measurements where the presence of an object can be determined with no photons being absorbed. We investigated several "interaction-free" imaging systems, i.e., systems that allow optical imaging of photosensitive objects with less than the classically expected amount of light being absorbed or scattered by the object. With the most promising system, we obtained high-resolution (10-mu m), one-dimensional profiles of a variety of objects (human hair, glass and metal wires, and cloth fibers) by raster scanning each object through the system. We discuss possible applications and the present and future limits for interaction-free imaging.
C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
RP White, AG (reprint author), Univ Calif Los Alamos Natl Lab, P-23,MS-H803, Los Alamos, NM 87545 USA.
RI White, Andrew/A-1088-2009
OI White, Andrew/0000-0001-9639-5200
NR 14
TC 46
Z9 46
U1 1
U2 11
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 JUL
PY 1998
VL 58
IS 1
BP 605
EP 613
DI 10.1103/PhysRevA.58.605
PG 9
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500078
ER
PT J
AU Deng, L
Payne, MG
Garrett, WR
AF Deng, L
Payne, MG
Garrett, WR
TI Nonlinear frequency conversion with short laser pulses and maximum
atomic coherence
SO PHYSICAL REVIEW A
LA English
DT Article
ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; DISPERSIVE PROPERTIES;
GENERATION; HYDROGEN; SYSTEMS
AB A perturbation treatment for Raman generation with a combination of long, short, and delayed laser pulses is presented. When the coupling and probe lasers are applied in a counterintuitive sequence, the fast oscillatory contributions to populations and coherence are eliminated by robust adiabatic passage, allowing a much simpler solution to the problem. Such counterintuitive and on-resonance operation allows effective electromagnetically induced transparency to evolve so that the probe laser photons will experience no absorption yet still fully participate in the nonlinear frequency conversion. Consequently, better conversion efficiency should be possible.
C1 Georgia So Univ, Dept Phys, Statesboro, GA 30460 USA.
Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA.
Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA.
RP Georgia So Univ, Dept Phys, Statesboro, GA 30460 USA.
RI Deng, Lu/B-3997-2012
NR 20
TC 18
Z9 18
U1 0
U2 0
PU AMER PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 2469-9926
EI 2469-9934
J9 PHYS REV A
JI Phys. Rev. A
PD JUL
PY 1998
VL 58
IS 1
BP 707
EP 712
DI 10.1103/PhysRevA.58.707
PG 6
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500091
ER
PT J
AU Vasilyev, A
Jasper, E
Berry, HG
Livingston, AE
Curtis, LJ
Cheng, S
Dunford, RW
AF Vasilyev, A
Jasper, E
Berry, HG
Livingston, AE
Curtis, LJ
Cheng, S
Dunford, RW
TI Lifetime of the 3p P-2(3/2) level in sodiumlike bromine (Br XXV)
SO PHYSICAL REVIEW A
LA English
DT Article
ID RESONANCE TRANSITIONS; BEAM-FOIL; ENERGIES; CESIUM; STATES; IONS; VII
AB Using the beam-foil spectroscopy technique, we have measured the decay time of the 3p P-2(3/2) level in sodiumlike bromine. The results, using an arbitrarily normalized decay curves analysis, are in good agreement with the most recent theoretical calculations. They also confirm an earlier experimental result in sodiumlike krypton, suggesting that some previous measurements of the lifetimes of 3p P-2(3/2) states of nearby isoelectronic ions are too high.
C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA.
Univ Toledo, Dept Phys, Toledo, OH 43606 USA.
Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA.
RP Vasilyev, A (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA.
NR 27
TC 5
Z9 5
U1 0
U2 0
PU AMERICAN PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 1050-2947
J9 PHYS REV A
JI Phys. Rev. A
PD JUL
PY 1998
VL 58
IS 1
BP 732
EP 735
DI 10.1103/PhysRevA.58.732
PG 4
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500097
ER
PT J
AU Halfmann, T
Yatsenko, LP
Shapiro, M
Shore, BW
Bergmann, K
AF Halfmann, T
Yatsenko, LP
Shapiro, M
Shore, BW
Bergmann, K
TI Population trapping and laser-induced continuum structure in helium:
Experiment and theory
SO PHYSICAL REVIEW A
LA English
DT Article
ID HARMONIC-GENERATION; IONIZATION; SODIUM; APPROXIMATION; TRANSITIONS;
RESONANCE; ATOMS; XENON
AB We report the observation of laser-induced structure (LICS) in the flat photoionization continuum of helium. The structure is a strong and spectrally sharp resonance, showing both enhanced and diminished ionization (a Beutler-Fano profile). Our observations show, in an otherwise unstructured continuum, pronounced ionization suppression (as much as 70%), which is due to population trapping associated with LICS. We also show the effect of dynamic Stark shifts upon the LICS profile. A discussed theoretical model, incorporating significant dynamic Stark shifts, gives a quantitatively accurate description of the line profile for a wide range of pulse intensities.
C1 Ukrainian Acad Sci, Inst Phys, UA-252650 Kiev, Ukraine.
Weizmann Inst Sci, Dept Chem Phys, IL-76100 Rehovot, Israel.
Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA.
RP Halfmann, T (reprint author), Univ Kaiserslautern, Fachbereich Phys, D-67653 Kaiserslautern, Germany.
RI Halfmann, Thomas/O-4588-2014; BERGMANN, KLAAS/D-5543-2011
OI Halfmann, Thomas/0000-0002-1222-2669;
NR 29
TC 48
Z9 49
U1 0
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 JUL
PY 1998
VL 58
IS 1
BP R46
EP R49
DI 10.1103/PhysRevA.58.R46
PG 4
WC Optics; Physics, Atomic, Molecular & Chemical
SC Optics; Physics
GA ZZ998
UT WOS:000074790500013
ER
PT J
AU Chau, R
Maple, MB
Robinson, RA
AF Chau, R
Maple, MB
Robinson, RA
TI Crystallographic evidence for chemical ordering in UCu5-xPdx
SO PHYSICAL REVIEW B
LA English
DT Article
ID FERMI-LIQUID BEHAVIOR; ELECTRON MATERIALS; KONDO DISORDER; ALLOYS
AB We report elastic neutron-diffraction measurements on UCu5-xPdx (x=0.65, 1.0, and 1.5) using the High-Intensity Powder Diffractometer instrument at the Los Alamos Neutron Science Center. Data from six detector banks were simultaneously refined using Rietveld analysis. From the refinements of the data, we find that for Pd concentrations x collisions at root s = 1.8 TeV is measured with the DO detector at Fermilab. The result is compared with QCD perturbative and resummation calculations over the p(T)(W) range from 0 to 200 GeV/c. The shape of the distribution is consistent with the theoretical prediction.
C1 NYU, New York, NY 10003 USA.
Univ Los Andes, Bogota, Colombia.
Univ Arizona, Tucson, AZ 85721 USA.
Boston Univ, Boston, MA 02215 USA.
Brookhaven Natl Lab, Upton, NY 11973 USA.
Brown Univ, Providence, RI 02912 USA.
Univ Buenos Aires, Buenos Aires, DF, Argentina.
Univ Calif Davis, Davis, CA 95616 USA.
Univ Calif Irvine, Irvine, CA 92697 USA.
Univ Calif Riverside, Riverside, CA 92521 USA.
Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil.
CINVESTAV, Mexico City 14000, DF, Mexico.
Columbia Univ, New York, NY 10027 USA.
Univ Delhi, Delhi 110007, India.
Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA.
Florida State Univ, Tallahassee, FL 32306 USA.
Univ Hawaii, Honolulu, HI 96822 USA.
Univ Illinois, Chicago, IL 60607 USA.
Indiana Univ, Bloomington, IN 47405 USA.
Iowa State Univ, Ames, IA 50011 USA.
Korea Univ, Seoul 136701, South Korea.
Kyungsung Univ, Pusan 608736, South Korea.
Inst Nucl Phys, Krakow, Poland.
Lawrence Berkeley Lab, Berkeley, CA 94720 USA.
Univ Calif Berkeley, Berkeley, CA 94720 USA.
Louisiana Tech Univ, Ruston, LA 71272 USA.
Univ Maryland, College Pk, MD 20742 USA.
Univ Michigan, Ann Arbor, MI 48109 USA.
Michigan State Univ, E Lansing, MI 48824 USA.
Inst Theoret & Expt Phys, Moscow 117259, Russia.
Moscow MV Lomonosov State Univ, Moscow, Russia.
Univ Nebraska, Lincoln, NE 68588 USA.
Northeastern Univ, Boston, MA 02115 USA.
No Illinois Univ, De Kalb, IL 60115 USA.
Northwestern Univ, Evanston, IL 60208 USA.
Univ Notre Dame, Notre Dame, IN 46556 USA.
Univ Oklahoma, Norman, OK 73019 USA.
Panjab Univ, Chandigarh 160014, India.
Protvino High Energy Phys Inst, Protvino 142284, Russia.
Purdue Univ, W Lafayette, IN 47907 USA.
Rice Univ, Houston, TX 77005 USA.
Univ Estado Rio de Janeiro, Rio De Janeiro, Brazil.
Univ Rochester, Rochester, NY 14627 USA.
Ctr Etud Saclay, CEA, DAPNIA, Serv Phys Particules, F-91191 Gif Sur Yvette, France.
Seoul Natl Univ, Seoul, South Korea.
SUNY Stony Brook, Stony Brook, NY 11794 USA.
Tata Inst Fundamental Res, Mumbai 400005, India.
Univ Texas, Arlington, TX 76019 USA.
Texas A&M Univ, College Stn, TX 77843 USA.
RP Abbott, B (reprint author), NYU, New York, NY 10003 USA.
RI Gutierrez, Phillip/C-1161-2011; Leflat, Alexander/D-7284-2012; Dudko,
Lev/D-7127-2012; Merkin, Mikhail/D-6809-2012; Kuleshov,
Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013;
Alves, Gilvan/C-4007-2013; Belyaev, Alexander/F-6637-2015; Kim, Sun
Kee/G-2042-2015; Aihara, Hiroaki/F-3854-2010; Shivpuri, R K/A-5848-2010;
Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016
OI Dudko, Lev/0000-0002-4462-3192; Kuleshov, Sergey/0000-0002-3065-326X;
De, Kaushik/0000-0002-5647-4489; Belyaev, Alexander/0000-0002-1733-4408;
Kim, Sun Kee/0000-0002-0013-0775; Aihara, Hiroaki/0000-0002-1907-5964;
Sznajder, Andre/0000-0001-6998-1108
NR 24
TC 25
Z9 25
U1 0
U2 1
PU AMER PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 0031-9007
EI 1079-7114
J9 PHYS REV LETT
JI Phys. Rev. Lett.
PD JUN 22
PY 1998
VL 80
IS 25
BP 5498
EP 5503
DI 10.1103/PhysRevLett.80.5498
PG 6
WC Physics, Multidisciplinary
SC Physics
GA ZV521
UT WOS:000074313000010
ER
PT J
AU Gormezano, C
Baranov, YF
Challis, CD
Coffey, I
Cottrell, GA
Ekedahl, AC
Greenfield, CM
Howman, AC
Huysmans, GTA
Keilhacker, M
Litaudon, X
Luce, TC
Rice, BW
Rochard, F
Sadler, GJ
Schild, PAJ
Sips, ACC
Soldner, FX
Strait, EJ
Tubbing, BJD
Wade, MR
Ward, DJ
AF Gormezano, C
Baranov, YF
Challis, CD
Coffey, I
Cottrell, GA
Ekedahl, AC
Greenfield, CM
Howman, AC
Huysmans, GTA
Keilhacker, M
Litaudon, X
Luce, TC
Rice, BW
Rochard, F
Sadler, GJ
Schild, PAJ
Sips, ACC
Soldner, FX
Strait, EJ
Tubbing, BJD
Wade, MR
Ward, DJ
TI Internal transport barriers in JET deuterium-tritium plasmas
SO PHYSICAL REVIEW LETTERS
LA English
DT Article
ID REVERSED MAGNETIC SHEAR; CONFINEMENT
AB The observation of internal transport barriers (ITBs) in which ion thermal diffusivity is reduced to a neoclassical level has been made for the first time in tokamak plasmas fueled with deuterium and tritium ions using a broad current density profile. The heating and current profiles required to obtain an ITB are similar in D-T and D-D plasmas. Central ion temperatures of 40 keV and plasma pressure gradients of 10(6) Pa/m were observed in a D-T plasma, leading to a fusion triple product n(i)T(i)tau(E) = 1.10(21) m(-3) keVs and 8.2 MW of fusion power. There is potential for further optimization as a step towards the development of efficient tokamak fusion reactors.
C1 Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England.
Chalmers Univ Technol, S-41296 Gothenburg, Sweden.
Gen Atom Co, San Diego, CA 92186 USA.
CEA, Cadarache, France.
Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA.
Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
RP Gormezano, C (reprint author), Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England.
NR 11
TC 102
Z9 102
U1 3
U2 11
PU AMERICAN PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 0031-9007
J9 PHYS REV LETT
JI Phys. Rev. Lett.
PD JUN 22
PY 1998
VL 80
IS 25
BP 5544
EP 5547
DI 10.1103/PhysRevLett.80.5544
PG 4
WC Physics, Multidisciplinary
SC Physics
GA ZV521
UT WOS:000074313000021
ER
PT J
AU Thomas, PR
Andrew, P
Balet, B
Bartlett, D
Bull, J
de Esch, B
Gibson, A
Gowers, C
Guo, H
Huysmans, G
Jones, T
Keilhacker, M
Koenig, R
Lennholm, M
Lomas, P
Maas, A
Marcus, F
Nave, F
Parail, V
Rimini, F
Strachan, J
Zastrow, KD
Zornig, N
AF Thomas, PR
Andrew, P
Balet, B
Bartlett, D
Bull, J
de Esch, B
Gibson, A
Gowers, C
Guo, H
Huysmans, G
Jones, T
Keilhacker, M
Koenig, R
Lennholm, M
Lomas, P
Maas, A
Marcus, F
Nave, F
Parail, V
Rimini, F
Strachan, J
Zastrow, KD
Zornig, N
TI Observation of alpha heating in JET DT plasmas
SO PHYSICAL REVIEW LETTERS
LA English
DT Article
ID TOKAMAK
AB An experiment at the Joint European Torus (JET) has demonstrated clear self-heating of a deuterium-tritium plasma by alpha particles produced in fusion reactions. The alpha heating was identified by scanning the plasma and neutral beam mixtures together from pure deuterium to nearly pure tritium in a 10.5 MW hot ion H mode. At an optimum mixture of (60 +/- 20)% T, the fusion gain (= P-fusion/P-absorbed) was 0.65 and the alpha heating showed clearly as a maximum in electron temperature. The change in temperature produced by alpha heating was T-e(0) = 1.3 +/- 0.23 keV in 12.2 keV. The effect of the heating could also be seen in the ion temperature and energy content.
C1 Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England.
EURATOM, IST, P-1096 Lisbon, Portugal.
Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA.
RP Thomas, PR (reprint author), Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England.
RI Nave, Maria/A-5581-2013
OI Nave, Maria/0000-0003-2078-6584
NR 9
TC 84
Z9 84
U1 1
U2 5
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 JUN 22
PY 1998
VL 80
IS 25
BP 5548
EP 5551
DI 10.1103/PhysRevLett.80.5548
PG 4
WC Physics, Multidisciplinary
SC Physics
GA ZV521
UT WOS:000074313000022
ER
PT J
AU Grigorian, L
Williams, KA
Fang, S
Sumanasekera, GU
Loper, AL
Dickey, EC
Pennycook, SJ
Eklund, PC
AF Grigorian, L
Williams, KA
Fang, S
Sumanasekera, GU
Loper, AL
Dickey, EC
Pennycook, SJ
Eklund, PC
TI Reversible intercalation of charged iodine chains into carbon nanotube
ropes
SO PHYSICAL REVIEW LETTERS
LA English
DT Article
AB We report intercalation of charged polyiodide chains into the interstitial channels in a single-wall carbon nanotube (SWNT) rope lattice, suggesting a new carbon chemistry for nanotubes, distinctly different from that of graphite and C-60. This structural model is supported by results from Raman spectroscopy, x-ray diffraction, Z-contrast electron microscopy, and electrical transport data. Iodine-doped SWNTs are found to be air stable, permitting the use of a variety of techniques to explore the effect of charge transfer on the physical properties of these novel quantum wires.
C1 Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA.
Univ Kentucky, Ctr Appl Energy Res, Lexington, KY 40511 USA.
Univ Kentucky, Dept Chem & Mat Engn, Lexington, KY 40506 USA.
Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA.
RP Grigorian, L (reprint author), Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA.
RI Dickey, Elizabeth/A-3368-2011
OI Dickey, Elizabeth/0000-0003-4005-7872
NR 23
TC 214
Z9 216
U1 4
U2 31
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 JUN 22
PY 1998
VL 80
IS 25
BP 5560
EP 5563
DI 10.1103/PhysRevLett.80.5560
PG 4
WC Physics, Multidisciplinary
SC Physics
GA ZV521
UT WOS:000074313000025
ER
PT J
AU Schwoerer-Bohning, M
Macrander, AT
Arms, DA
AF Schwoerer-Bohning, M
Macrander, AT
Arms, DA
TI Phonon dispersion of diamond measured by inelastic x-ray scattering
SO PHYSICAL REVIEW LETTERS
LA English
DT Article
ID NEUTRON-SCATTERING; 2-PHONON SPECTRUM; LATTICE-DYNAMICS; RAMAN-SPECTRUM;
FREQUENCIES
AB We report on a study of phonons in diamond using a new instrument for high resolution inelastic x-ray scattering at the Advanced Photon Source. We have paid particular attention to possible overbending of the most energetic branches, i.e., LO along both Gamma - X (= Delta) and Gamma - L (= Lambda) and the elliptically polarized Sigma(3) branch along Gamma - K (= Sigma). Overbending along all three directions has been invoked in recent years to explain a famous and extraordinary peak in the two-phonon Raman spectrum. Our data reveal overbending only along Delta.
C1 Argonne Natl Lab, Adv Photon Source, Expt Facil Div, Argonne, IL 60439 USA.
Univ Illinois, Dept Phys, Urbana, IL 61801 USA.
Univ Illinois, Frederick Seitz Mat Res Lab, Urbana, IL 61801 USA.
RP Schwoerer-Bohning, M (reprint author), Argonne Natl Lab, Adv Photon Source, Expt Facil Div, 9700 S Cass Ave, Argonne, IL 60439 USA.
EM schwoere@aps.anl.gov
NR 24
TC 62
Z9 62
U1 2
U2 15
PU AMERICAN PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 0031-9007
J9 PHYS REV LETT
JI Phys. Rev. Lett.
PD JUN 22
PY 1998
VL 80
IS 25
BP 5572
EP 5575
DI 10.1103/PhysRevLett.80.5572
PG 4
WC Physics, Multidisciplinary
SC Physics
GA ZV521
UT WOS:000074313000028
ER
PT J
AU Verdozzi, C
Jennison, DR
Schultz, PA
Sears, MP
Barbour, JC
Potter, BG
AF Verdozzi, C
Jennison, DR
Schultz, PA
Sears, MP
Barbour, JC
Potter, BG
TI Unusual structural relaxation for rare-earth impurities in sapphire: Ab
initio study of lanthanum
SO PHYSICAL REVIEW LETTERS
LA English
DT Article
ID ELECTRONIC-STRUCTURE; CORUNDUM; PSEUDOPOTENTIALS; ALPHA-AL2O3;
SIMULATION; ALUMINA; STATES; MODEL
AB A first-principles density-functional local density approximation study of substitutional La, using 120-atom supercells of alpha-Al2 O3, shows that La assumes a highly displaced position, moving over 0.5 Angstrom from the original Al site. The La-O nearest neighbor distance is much smaller than the sum of standard La+3 and O-2 ionic radii. This is due to La being more ionic than in its own oxide, and to the role of the 5d shell, as the electron density within the displaced La is quite anisotropic. We discuss the implications for a systematic description of rare-earth ions implanted in sapphire.
C1 Sandia Natl Labs, Albuquerque, NM 87185 USA.
Univ Liverpool, IRCSS, Liverpool L69 3BX, Merseyside, England.
RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA.
EM drjenni@sandia.gov
NR 35
TC 38
Z9 39
U1 0
U2 4
PU AMER PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 0031-9007
EI 1079-7114
J9 PHYS REV LETT
JI Phys. Rev. Lett.
PD JUN 22
PY 1998
VL 80
IS 25
BP 5615
EP 5618
DI 10.1103/PhysRevLett.80.5615
PG 4
WC Physics, Multidisciplinary
SC Physics
GA ZV521
UT WOS:000074313000039
ER
PT J
AU Requardt, H
Nad, FY
Monceau, P
Currat, R
Lorenzo, JE
Brazovskii, S
Kirova, N
Grubel, G
Vettier, C
AF Requardt, H
Nad, FY
Monceau, P
Currat, R
Lorenzo, JE
Brazovskii, S
Kirova, N
Grubel, G
Vettier, C
TI Direct observation of charge density wave current conversion by
spatially resolved synchrotron x-ray studies in NbSe3
SO PHYSICAL REVIEW LETTERS
LA English
DT Article
ID PHASE-SLIP; NIOBIUM TRISELENIDE; GENERATION; NOISE
AB We present results on the normal-collective current conversion processes and associated deformation profile for a charge density wave in the sliding state. High resolution x-ray measurements of the satellite positional shift have been performed on NbSe3 at 90 K. The shift q has been determined in the vicinity of the contacts by applying direct currents. We observe a steep variation of g near the contact, modeled in terms of dislocation loops (DL) nucleated at host defects. A small constant gradient in the sample's central part indicates incomplete conversion, consistent with DL pinning.
C1 CNRS, Ctr Rech Tres Basses Temp, F-38042 Grenoble, France.
Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France.
Russian Acad Sci, Inst Radio Engn & Elect, Moscow 103907, Russia.
CNRS, Cristallog Lab, F-38042 Grenoble, France.
LD Landau Theoret Phys Inst, Moscow, Russia.
European Synchrotron Radiat Facil, F-38043 Grenoble, France.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
RP Requardt, H (reprint author), CNRS, Ctr Rech Tres Basses Temp, BP 166, F-38042 Grenoble, France.
RI Brazovskii, Serguei/A-9608-2012
OI Brazovskii, Serguei/0000-0001-8147-9655
NR 25
TC 72
Z9 72
U1 1
U2 4
PU AMERICAN PHYSICAL SOC
PI COLLEGE PK
PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
SN 0031-9007
J9 PHYS REV LETT
JI Phys. Rev. Lett.
PD JUN 22
PY 1998
VL 80
IS 25
BP 5631
EP 5634
DI 10.1103/PhysRevLett.80.5631
PG 4
WC Physics, Multidisciplinary
SC Physics
GA ZV521
UT WOS:000074313000043
ER
PT J
AU Mobarak, M
Berger, H
Lorusso, GF
Capozzi, V
Perna, G
Ibrahim, MM
Margaritondo, G
AF Mobarak, M
Berger, H
Lorusso, GF
Capozzi, V
Perna, G
Ibrahim, MM
Margaritondo, G
TI The growth and properties of single crystals of GaInTe2, a ternary
chalcogenide semiconductor
SO JOURNAL OF PHYSICS D-APPLIED PHYSICS
LA English
DT Article
ID GALLIUM SELENIDE; GASE; TLINS2; TEMPERATURE; EXCITONS
AB Single crystals of GaInTe2 were grown from a melt and characterized by various experimental techniques, such as x-ray diffraction, x-ray photoelectron spectroscopy (XPS), and electrical and photoluminescence (PL) measurements. Our investigation evaluated important parameters of this challenging material. In particular, we studied here for the first time the electronic structure, the excitonic effects and the impurity bound states of GaInTe2, by means of XPS and by analysing dependences on the temperature and the excitation intensity of the PL spectra.
C1 Quena S Valley Univ, Dept Phys, CH-1015 Lausanne, Switzerland.
Ecole Polytech Fed Lausanne, Inst Phys Appl, CH-1015 Lausanne, Switzerland.
Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Lab, Berkeley, CA 94720 USA.
Univ Bari, Dipartimento Fis, I-70126 Bari, Italy.
Ist Nazl Fis Mat, I-70126 Bari, Italy.
Fac Sci, Dept Phys, Sohag, Egypt.
RP Mobarak, M (reprint author), Quena S Valley Univ, Dept Phys, CH-1015 Lausanne, Switzerland.
RI Margaritondo, Giorgio/B-1367-2008
NR 20
TC 1
Z9 1
U1 0
U2 4
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0022-3727
J9 J PHYS D APPL PHYS
JI J. Phys. D-Appl. Phys.
PD JUN 21
PY 1998
VL 31
IS 12
BP 1433
EP 1437
DI 10.1088/0022-3727/31/12/006
PG 5
WC Physics, Applied
SC Physics
GA ZY742
UT WOS:000074654800006
ER
PT J
AU Tajima, T
Chen, P
AF Tajima, T
Chen, P
TI Near- and long-term applications of plasma-based accelerators
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS
SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
LA English
DT Article; Proceedings Paper
CT 13th Advanced ICFA Beam Dynamics Workshop / 1st ICFA Novel and Advanced
Accelerator Workshop - The 2nd Generation Plasma Accelerators
CY JUL 14-18, 1997
CL KYOTO RES PARK, JAPAN
DE intense laser; wakefield accelerator; colliders; X-rays; snow-plow
acceleration; inverse Compton scattering; ion acceleration; positron
source
AB A variety of near-term applications has been suggested and several long-term goals? including high-energy colliders, have been discussed. Applications of laser (or beam)-driven accelerators along with applications of advanced laser itself have been considered, such as for X-ray sources. Some of the near term applications are realistic and exciting enough that they deserve serious further investigations. We Feint out some of these future opportunities. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Univ Texas, Dept Phys, Inst Fus Studies, Austin, TX 78712 USA.
Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA.
RP Tajima, T (reprint author), Univ Texas, Dept Phys, Inst Fus Studies, Austin, TX 78712 USA.
NR 3
TC 1
Z9 1
U1 0
U2 1
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-9002
J9 NUCL INSTRUM METH A
JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc.
Equip.
PD JUN 21
PY 1998
VL 410
IS 3
BP 344
EP 346
DI 10.1016/S0168-9002(98)00163-6
PG 3
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Nuclear; Physics, Particles & Fields
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 100VH
UT WOS:000074835700004
ER
PT J
AU Assmann, R
Chen, P
Decker, FJ
Iverson, R
Raimondi, P
Raubenheimer, T
Rokni, S
Siemann, R
Walz, D
Whittum, D
Chattopadhyay, S
Leemans, W
Katsouleas, T
Lee, S
Clayton, C
Joshi, C
Marsh, K
Mori, W
Wang, G
AF Assmann, R
Chen, P
Decker, FJ
Iverson, R
Raimondi, P
Raubenheimer, T
Rokni, S
Siemann, R
Walz, D
Whittum, D
Chattopadhyay, S
Leemans, W
Katsouleas, T
Lee, S
Clayton, C
Joshi, C
Marsh, K
Mori, W
Wang, G
TI Proposal for a one GeV plasma wakefield acceleration experiment at SLAC
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS
SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
LA English
DT Article; Proceedings Paper
CT 13th Advanced ICFA Beam Dynamics Workshop / 1st ICFA Novel and Advanced
Accelerator Workshop - The 2nd Generation Plasma Accelerators
CY JUL 14-18, 1997
CL KYOTO RES PARK, JAPAN
ID WAKE-FIELD ACCELERATOR; WAVE-BREAKING
AB A plasma-based wakefield acceleration experiment E-157 has been approved at SLAG to study acceleration of parts of an SLC bunch by up to 1 GeV/m over a length of 1 m. A single SLC bunch is used to both induce wakefields in the 1 m long plasma and to witness the resulting beam acceleration. The experiment will explore and further develop the techniques that are needed to apply high-gradient plasma wakefield acceleration to large-scale accelerators. The Im length of the experiment is about two orders of magnitude larger than for other high gradient plasma wakefield acceleration experiments and the 1 GeV/m accelerating gradient is roughly ten times larger than that achieved with conventional metallic structures. Using existing SLAG facilities, the experiment will study high gradient acceleration at the forefront of advanced accelerator research. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA.
Univ So Calif, Los Angeles, CA 90089 USA.
Univ Calif Los Angeles, Los Angeles, CA 90024 USA.
RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
EM assmann@slac.stanford.edu; chen@slac.stanford.edu; katsoule@usc.edu;
cclayton@ea.ucla.edu; mori@physics.ucla.edu
RI Assmann, Ralph/L-8457-2016
NR 24
TC 3
Z9 3
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-9002
EI 1872-9576
J9 NUCL INSTRUM METH A
JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc.
Equip.
PD JUN 21
PY 1998
VL 410
IS 3
BP 396
EP 406
DI 10.1016/S0168-9002(98)00169-7
PG 11
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Nuclear; Physics, Particles & Fields
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 100VH
UT WOS:000074835700012
ER
PT J
AU Chen, P
Cline, D
Craddock, W
Decker, FJ
Iverson, R
Katsouleas, T
Kwok, P
Leemans, W
Masuda, S
Meyerhofer, DD
Nakajima, K
Ogata, A
Raimondi, P
Sessler, A
Walz, D
Weidemann, A
AF Chen, P
Cline, D
Craddock, W
Decker, FJ
Iverson, R
Katsouleas, T
Kwok, P
Leemans, W
Masuda, S
Meyerhofer, DD
Nakajima, K
Ogata, A
Raimondi, P
Sessler, A
Walz, D
Weidemann, A
TI Plasma lens experiment at the final focus test beam
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS
SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
LA English
DT Article; Proceedings Paper
CT 13th Advanced ICFA Beam Dynamics Workshop / 1st ICFA Novel and Advanced
Accelerator Workshop - The 2nd Generation Plasma Accelerators
CY JUL 14-18, 1997
CL KYOTO RES PARK, JAPAN
ID CHIRPED-PULSE-AMPLIFICATION; ELECTRON-BEAM; ACCELERATION; SUPPRESSION;
COLLIDERS
AB The proposed plasma lens experiment at the Final focus Test Beam (FFTB) facility of the Stanford Linear Accelerator Center (Chen et al. SLAG, 1997) [1] has been approved by the adminstration. The experiment would allow the examination of plasma focusing devices for particle beams in the parameter regime of interest to future high-energy colliders. It is expected to lead to compact plasma lens designs capable of focusing the beam to unprecedented small spot sizes. (C) 1998 Published by Elsevier Science B.V. All rights reserved.
C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
Univ Calif Los Angeles, Los Angeles, CA USA.
Univ So Calif, Los Angeles, CA USA.
Lawrence Berkeley Lab, Berkeley, CA USA.
Univ Rochester, Rochester, NY USA.
Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan.
Univ Tennessee, Knoxville, TN USA.
RP Chen, P (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, POB 4349 MS26, Stanford, CA 94309 USA.
NR 31
TC 0
Z9 0
U1 0
U2 1
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-9002
J9 NUCL INSTRUM METH A
JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc.
Equip.
PD JUN 21
PY 1998
VL 410
IS 3
BP 407
EP 417
DI 10.1016/S0168-9002(98)00153-3
PG 11
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Nuclear; Physics, Particles & Fields
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 100VH
UT WOS:000074835700013
ER
PT J
AU Gai, W
Li, X
Conde, M
Power, J
Schoessow, P
AF Gai, W
Li, X
Conde, M
Power, J
Schoessow, P
TI A high-charge and short-pulse RF photocathode gun for wake-field
acceleration
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS
SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
LA English
DT Article; Proceedings Paper
CT 13th Advanced ICFA Beam Dynamics Workshop / 1st ICFA Novel and Advanced
Accelerator Workshop - The 2nd Generation Plasma Accelerators
CY JUL 14-18, 1997
CL KYOTO RES PARK, JAPAN
DE high current; photoinjector; emittance; wake-field acceleration
AB In this paper we present a design report on 1-1/2 cell, L-Band RF photocathode gun which is capable of generating and accelerating electron beams with peak currents > 10 kA. We address several critical issues of high-current RF photoinjectors such as longitudinal space charge effect, and transverse emittance growth. Unlike conventional short electron pulse generation, this design does not require magnetic pulse compression. Based on numerical simulations using SUPERFISH and PARMELA, this design will produce 100 nC beam at 18 MeV with r.m.s. bunch length 1.25 mm and normalized transverse emittance 108 mm mrad. Applications of this source beam for wake-field acceleration are also discussed. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA.
RP Gai, W (reprint author), Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA.
NR 16
TC 6
Z9 7
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 JUN 21
PY 1998
VL 410
IS 3
BP 431
EP 436
DI 10.1016/S0168-9002(98)00174-0
PG 6
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Nuclear; Physics, Particles & Fields
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 100VH
UT WOS:000074835700016
ER
PT J
AU Chen, P
Spitkovsky, A
Katsouleas, T
Mori, WB
AF Chen, P
Spitkovsky, A
Katsouleas, T
Mori, WB
TI Transformer ratio and pulse shaping in laser wakefield accelerator
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS
SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
LA English
DT Article; Proceedings Paper
CT 13th Advanced ICFA Beam Dynamics Workshop / 1st ICFA Novel and Advanced
Accelerator Workshop - The 2nd Generation Plasma Accelerators
CY JUL 14-18, 1997
CL KYOTO RES PARK, JAPAN
ID PLASMA
AB We show that, in complete analogy to the electron-beam driven Plasma Wakefield Accelerator (PWFA), an optimal transformer ratio can be attained in the laser driven Laser Wakefield Accelerator (LWFA), by properly shaping the longitudinal profile of the driving laser pulse. The concept of transformer ratio in LWFA is introduced and the optimal laser pulse shape is derived in the linear regime of laser-plasma interaction. We show that in the linear regime of plasma perturbation the requirement for the laser pulse shape and the resultant optimal transformer ratio are identical for LWFA and PWFA concepts. (C) 1998 Published by Elsevier Science B.V. All rights reserved.
C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.
Univ So Calif, Dept EE & Electrophys, Los Angeles, CA 90089 USA.
Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90024 USA.
RP Chen, P (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
NR 13
TC 6
Z9 6
U1 0
U2 1
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-9002
J9 NUCL INSTRUM METH A
JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc.
Equip.
PD JUN 21
PY 1998
VL 410
IS 3
BP 488
EP 492
PG 5
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Nuclear; Physics, Particles & Fields
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 100VH
UT WOS:000074835700022
ER
PT J
AU Pogorelsky, IV
AF Pogorelsky, IV
TI Prospects for laser wakefield accelerators and colliders using CO2 laser
drivers
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS
SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
LA English
DT Article; Proceedings Paper
CT 13th Advanced ICFA Beam Dynamics Workshop / 1st ICFA Novel and Advanced
Accelerator Workshop - The 2nd Generation Plasma Accelerators
CY JUL 14-18, 1997
CL KYOTO RES PARK, JAPAN
ID ELECTRON ACCELERATION; PLASMA-WAVES; PULSES; LIGHT
AB Energy directly acquired by an electron from the laser electromagnetic field is quadratically proportional to the laser wavelength. Exploiting this feature, the emerging terawatt picosecond (TWps) CO2 lasers, having an order of magnitude longer wavelength than the well-known table-top terawatt (T-3) picosecond solid state lasers, offer new opportunities for strong-field physics research. Laser accelerators serve as an example when application of the new class of lasers will result in enhancement in gas ionization, plasma wave excitation, and relativistic self-focusing. Ponderomotively strong CO2 laser permits a 100 times reduction in the plasma density without impeding the acceleration. The improved performance of the low-pressure laser wakefield accelerators (LWFA) is potentially due to higher electric charge per accelerated bunch and better monochromaticity. The multi-kilowatt average power high repetition rate capability of the TWps-CO2 laser technology opens new opportunities in development of compact, similar to 1 m long, GeV accelerators and <1km long high-luminosity multi-stage LWFA colliders of the TeV scale. The first TWps-CO2, laser is under construction at the BNL Accelerator Test Facility (ATF). (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Brookhaven Natl Lab, Accelerator Test Facil, Upton, NY 11973 USA.
RP Pogorelsky, IV (reprint author), Brookhaven Natl Lab, Accelerator Test Facil, 725C, Upton, NY 11973 USA.
NR 21
TC 13
Z9 13
U1 0
U2 1
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-9002
J9 NUCL INSTRUM METH A
JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc.
Equip.
PD JUN 21
PY 1998
VL 410
IS 3
BP 524
EP 531
DI 10.1016/S0168-9002(98)00160-0
PG 8
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Nuclear; Physics, Particles & Fields
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 100VH
UT WOS:000074835700029
ER
PT J
AU Rosenzweig, J
Barov, N
Murokh, A
Colby, E
Colestock, P
AF Rosenzweig, J
Barov, N
Murokh, A
Colby, E
Colestock, P
TI Towards a plasma wake-field acceleration-based linear collider
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS
SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
LA English
DT Article; Proceedings Paper
CT 13th Advanced ICFA Beam Dynamics Workshop / 1st ICFA Novel and Advanced
Accelerator Workshop - The 2nd Generation Plasma Accelerators
CY JUL 14-18, 1997
CL KYOTO RES PARK, JAPAN
ID INJECTOR; PULSE
AB A proposal for a linear collider based on an advanced accelerator scheme, plasma wake-field acceleration in the extremely nonlinear regime, is discussed. In this regime, many of the drawbacks associated with preservation of beam quality during acceleration in plasma are mitigated. The scaling of all beam and wake parameters with respect to plasma wavelength is examined. Experimental progress towards high-gradient acceleration in this scheme is reviewed. We then examine a linear collider based on staging of many modules of plasma wake-field accelerator, all driven by a high average current, pulse compressed, RF photoinjector-fed linac. Issue of beam lending, efficiency, optimized stage length, and power efficiency are discussed. A proof-of-principle experimental test of the staging concept at the Fermilab test facility is discussed. (C) 1998 Published by Elsevier Science B.V. All rights reserved.
C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA.
Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA.
RP Univ Calif Los Angeles, Dept Phys & Astron, 405 Hilgard Ave, Los Angeles, CA 90095 USA.
NR 27
TC 16
Z9 16
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-9002
EI 1872-9576
J9 NUCL INSTRUM METH A
JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc.
Equip.
PD JUN 21
PY 1998
VL 410
IS 3
BP 532
EP 543
DI 10.1016/S0168-9002(98)00186-7
PG 12
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Nuclear; Physics, Particles & Fields
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 100VH
UT WOS:000074835700030
ER
PT J
AU Assmann, R
Yokoya, K
AF Assmann, R
Yokoya, K
TI Transverse beam dynamics in plasma-based linacs
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS
SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
LA English
DT Article; Proceedings Paper
CT 13th Advanced ICFA Beam Dynamics Workshop / 1st ICFA Novel and Advanced
Accelerator Workshop - The 2nd Generation Plasma Accelerators
CY JUL 14-18, 1997
CL KYOTO RES PARK, JAPAN
AB The transverse beam dynamics in plasma channels of possible future plasma-based linacs is discussed. We represent the transverse focusing of both a beam-driven and a laser-driven plasma wakefield accelerator by a uniform focusing channel. The transverse beam sizes and a basic offset tolerance are calculated, finding that sub-micron beams must be transported with even smaller offset tolerances. The results emphasize the need to pursue further ideas for plasma structures with high-acceleration gradients but reduced transverse wakefields.;(C) 1998 Elsevier Science B.V. All rights reserved.
C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan.
RP Assmann, R (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
RI Assmann, Ralph/L-8457-2016
NR 6
TC 17
Z9 17
U1 1
U2 3
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-9002
J9 NUCL INSTRUM METH A
JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc.
Equip.
PD JUN 21
PY 1998
VL 410
IS 3
BP 544
EP 548
DI 10.1016/S0168-9002(98)00187-9
PG 5
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Nuclear; Physics, Particles & Fields
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 100VH
UT WOS:000074835700031
ER
PT J
AU Kulp, TJ
Powers, P
Kennedy, R
Goers, UB
AF Kulp, TJ
Powers, P
Kennedy, R
Goers, UB
TI Development of a pulsed backscatter-absorption gas-imaging system and
its application to the visualization of natural gas leaks
SO APPLIED OPTICS
LA English
DT Article
AB The design and evaluation of a backscatter-absorption gas-imaging sensor that operates in a pulsed mode is described. It is capable of video visualization of natural gas leaks. Its development was motivated by the need for a methane imaging system to operate at ranges and sensitivities useful to the natural gas industry. The imager employs pulsed laser illumination at a repetition rate of 30 Hz and an average power of similar to 150 mW to image gas at standoff ranges of as long as 100 m, using a backscatter target with a reflectivity of 0.016 sr(-1). This is a tenfold improvement over an earlier raster-scanned imager. Natural gas leaks as small as 1.6 X 10(-4) standard liters/s [equal to 0.02 standard cubic feet per hour (scfh)] were imaged at short ranges; leaks as low as 7.9 X 10(-4) standard liters/s (0.1 scfh) were observed at long ranges. Data are compared with model predictions, and potential extensions to a fieldable prototype are discussed. The optimization of a direct-injection focal-plane array for detecting short (nanosecond) laser pulses is described. (C) 1998 Optical Society of America.
C1 Sandia Natl Labs, Livermore, CA 94551 USA.
RP Kulp, TJ (reprint author), Sandia Natl Labs, MS 9051,POB 969, Livermore, CA 94551 USA.
NR 12
TC 16
Z9 16
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 JUN 20
PY 1998
VL 37
IS 18
BP 3912
EP 3922
DI 10.1364/AO.37.003912
PG 11
WC Optics
SC Optics
GA ZT886
UT WOS:000074127900013
PM 18273359
ER
PT J
AU Koplow, JP
Kliner, DAV
Goldberg, L
AF Koplow, JP
Kliner, DAV
Goldberg, L
TI Development of a narrow-band, tunable, frequency-quadrupled diode laser
for UV absorption spectroscopy
SO APPLIED OPTICS
LA English
DT Article
ID HIGH-POWER; 2ND-HARMONIC GENERATION; SEMICONDUCTOR-LASER; OPTICAL
AMPLIFIER; COEFFICIENTS; SYSTEM; STATE; LIGHT; BLUE; SO2
AB A compact, lightweight, low-power-consumption source of tunable, narrow-bandwidth blue and UV radiation is described. In this source, a single-longitudinal-mode diode laser seeds a pulsed, GaAlAs tapered amplifier whose similar to 860-nm output is frequency quadrupled by two stages of single-pass frequency doubling. Performance of the laser system is characterized over a wide range of amplifier duty cycles (0.1-1.0), pulse durations (50 ns-1.0 mu s), peak currents (less than or equal to 14 A), and average currents (less than or equal to 2.0 A). The capabilities and limitations of this source are discussed. We recorded high-resolution, Doppler-limited absorption spectra of nitric oxide and sulfur dioxide near 215 MI; the SO2 spectrum was found to have significantly more structure and higher peak absorption cross sections than previously reported. (C) 1998 Optical Society of America.
C1 USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA.
Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA.
RP Koplow, JP (reprint author), USN, Res Lab, Div Opt Sci, Washington, DC 20375 USA.
NR 31
TC 21
Z9 23
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 JUN 20
PY 1998
VL 37
IS 18
BP 3954
EP 3960
DI 10.1364/AO.37.003954
PG 7
WC Optics
SC Optics
GA ZT886
UT WOS:000074127900017
PM 18273363
ER
PT J
AU Odenwald, S
Newmark, J
Smoot, G
AF Odenwald, S
Newmark, J
Smoot, G
TI A study of external galaxies detected by the COBE Diffuse Infrared
Background Experiment
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE diffuse radiation; dust, extinction; galaxies, ISM; galaxies,
photometry; infrared, galaxies; surveys
ID INTERSTELLAR DUST; IRAS OBSERVATIONS; EMISSION; SAMPLE
AB A comparison of the COBE1 Diffuse Infrared Background Experiment (DIRBE) all-sky survey with the locations of known galaxies in the IRAS Catalog of Extragalactic Objects and the Center for Astrophysics Catalog of Galaxies led to the detection of as many as 57 galaxies. In this paper, we present the photometric data for these galaxies and an analysis of the seven galaxies that were detected at lambda > 100 mu m. Estimates of the ratio of the mass of the cold dust (CD) component detected at T-d = 20-30 K to a very cold dust (VCD) component with T-d approximate to 10-15 K suggest that between 2%-100% of the cirrus-like CD mass can also exist in many of these galaxies as VCD. In one galaxy, M33, the DIRBE photometry at 240 mu m suggests as much as 26 times as much VCD may be present as compared to the cirrus-like component. Further submillimeter measurements of this galaxy are required to verify such a large population of VCD. We also present 10 galaxies that were detected in the sky region not previously surveyed by IRAS and that can be used to construct a flux-limited all-sky catalog of galaxies brighter than 1000 Jy with a modest completeness limit of about 65%.
C1 Raytheon STX, Goddard SFC, Greenbelt, MD 20771 USA.
Appl Res Corp, Landover, MD 20785 USA.
Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA.
RP Raytheon STX, Goddard SFC, Code 630-0, Greenbelt, MD 20771 USA.
NR 37
TC 27
Z9 27
U1 0
U2 0
PU IOP PUBLISHING LTD
PI BRISTOL
PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
SN 0004-637X
EI 1538-4357
J9 ASTROPHYS J
JI Astrophys. J.
PD JUN 20
PY 1998
VL 500
IS 2
BP 554
EP 568
DI 10.1086/305737
PN 1
PG 15
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA ZX419
UT WOS:000074513900002
ER
PT J
AU Tran, HD
Cohen, MH
Ogle, PM
Goodrich, RW
Alighieri, SD
AF Tran, HD
Cohen, MH
Ogle, PM
Goodrich, RW
Alighieri, SD
TI Scattered radiation from obscured quasars in distant radio galaxies
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies, active; galaxies, jets; polarization; quasars, general; radio,
continuum, galaxies; scattering
ID BROAD-LINE REGIONS; HIGH SPATIAL-RESOLUTION; HIGH-REDSHIFT; SEYFERT-2
GALAXIES; OPTICAL POLARIZATION; UNIFICATION SCHEMES; GALACTIC NUCLEI;
STAR FORMATION; SPECTROPOLARIMETRY; SPECTRUM
AB We present optical spectropolarimetric and imaging polarimetric observations of four high-redshift radio galaxies (HzRGs) obtained with the Low Resolution Imaging Spectrometer of the 10 m Keck I telescope. A broad Mg IT lambda 2800 emission line is detected in the total and polarized flux spectra of 3C 265 and 3C 277.2. The fractional polarization is high, and both it and the position angle are constant with wavelength after accounting for dilution by unpolarized starlight of the host galaxy, which can contribute substantially. An extended unpolarized continuum similar to that observed in other active galactic nuclei is also detected. Imaging polarimetry reveals a rough double-fan morphology of the polarized light coincident with the extended aligned emission regions, with the position angle essentially perpendicular to the radial structure of the extended UV/optical emission and with the degree of polarization increasing with radius away from the nucleus. The radio jets lie inside the extended emission regions and, like every radius, are roughly perpendicular to the polarization position angle. These results strengthen the view that powerful radio galaxies would be called quasars if viewed from the proper direction. Based on the polarimetric data presented in this paper and in previous studies, scattering of radiation from an obscured quasar source appears to be the preferred interpretation over jet-induced star formation for explaining the alignment effect in HzRGs. Both electrons and dust can play a major role in the scattering process. However, the lack of strong direct evidence for either case and our ignorance of the properties and distribution of the scatterers in these galaxies make it very difficult to discriminate between the two. Our data reveal a chance alignment of 3C 343.1 with a foreground galaxy, which dominates the observed optical flux from the system.
C1 Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA.
CALTECH, Palomar Observ, Pasadena, CA 91125 USA.
CARA Keck Observ, Kamuela, HI 96743 USA.
Osservatorio Astrofis Arcetri, I-50125 Florence, Italy.
RP Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, POB 808,7000 East Ave,L-413, Livermore, CA 94550 USA.
EM htran@igpp.llnl.gov; mhc@astro.caltech.edu; pmo@astro.caltech.edu;
goodrich@keck.hawaii.edu; sperello@arcetri.astro.it
RI di Serego Alighieri, Sperello/E-4067-2010
OI di Serego Alighieri, Sperello/0000-0001-8769-2692
NR 81
TC 33
Z9 33
U1 0
U2 0
PU IOP PUBLISHING LTD
PI BRISTOL
PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
SN 0004-637X
EI 1538-4357
J9 ASTROPHYS J
JI Astrophys. J.
PD JUN 20
PY 1998
VL 500
IS 2
BP 660
EP 672
DI 10.1086/305752
PN 1
PG 13
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA ZX419
UT WOS:000074513900012
ER
PT J
AU Strohmayer, TE
Fenimore, EE
Murakami, T
Yoshida, A
AF Strohmayer, TE
Fenimore, EE
Murakami, T
Yoshida, A
TI X-ray spectral characteristics of Ginga gamma-ray bursts
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE gamma rays : bursts; radiation mechanisms : nonthermal; X-rays : bursts
ID BATSE OBSERVATIONS; EVOLUTION; SPECTROSCOPY; ABSORPTION; FEATURES;
EMISSION; CATALOG; BRIGHT
AB We have investigated the spectral characteristics of a sample of bright gamma-ray bursts detected with the gamma-ray burst sensors aboard the satellite Ginga. This instrument employed a proportional and scintillation counter to provide sensitivity to photons in the 2-400 keV region and as such provided a unique opportunity to characterize the largely unexplored X-ray properties of gamma-ray bursts. The photon spectra of the Ginga bursts are well described by a low-energy slope, a bend energy, and a high-energy slope. In the energy range where they can be compared, this result is consistent with burst spectral analyses obtained from the BATSE experiment aboard the Compton Gamma-Ray Observatory. However, below 20 keV we find evidence for a positive spectral number index in approximately 40% of our burst sample, with some evidence for a strong rolloff at lower energies in a few events. There is a correlation (Pearson's r = -0.62) between the low-energy slope and the bend energy. We find that the distribution of spectral bend energies extends below 10 keV. There has been some concern in cosmological models of gamma-ray bursts (GRBs) that the bend energy covers only a small dynamic range. Our result extends the observed dynamic range, and, since we observe bend energies down to the limit of our instrument, perhaps observations have not yet limited the range. The Ginga trigger range was virtually the same as that of BATSE, yet we find a different range of fit parameters. One possible explanation might be that GRBs have two break energies, one often in the 50-500 keV range and the other near 5 keV. Both BATSE and Ginga fit with only a single break energy, so BATSE tends to find breaks near the center of its energy range, and we tend to find breaks in our energy range. The observed ratio of energy emitted in the X-rays relative to the gamma rays can be much larger than a few percent and, in fact, is sometimes larger than unity. The average for our 22 bursts is 24%. We also investigated spectral evolution in two bursts. In these events we find strong evidence for spectral softening as well as a correlation between photon intensity and spectral hardness. We also find that the X-ray signal below 30 keV itself softens in both of these events. There is one example of a strong X-ray excess at low energy. In addition to providing further constraints on gamma-ray burst models, the description provided here of burst spectra down to 2 keV should prove useful to future planned efforts to detect bursts at X-ray energies.
C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
Inst Space & Astronaut Sci, Kanagawa 229, Japan.
RIKEN, Inst Phys & Chem Res, Wako, Saitama 35101, Japan.
RP NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Mail Code 666, Greenbelt, MD 20771 USA.
EM stroh@pcasrv.gsfc.nasa.gov; efenimore@lanl.gov
NR 44
TC 83
Z9 84
U1 0
U2 0
PU IOP PUBLISHING LTD
PI BRISTOL
PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
SN 0004-637X
EI 1538-4357
J9 ASTROPHYS J
JI Astrophys. J.
PD JUN 20
PY 1998
VL 500
IS 2
BP 873
EP 887
DI 10.1086/305735
PN 1
PG 15
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA ZX419
UT WOS:000074513900030
ER
PT J
AU Drake, RP
Carroll, JJ
Estabrook, K
Glendinning, SG
Remington, BA
Wallace, R
McCray, R
AF Drake, RP
Carroll, JJ
Estabrook, K
Glendinning, SG
Remington, BA
Wallace, R
McCray, R
TI Development of a laboratory environment to test models of supernova
remnant formation
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE hydrodynamics; instabilities; supernova remnants
AB Increasingly sophisticated computational models are being used to interpret the increasingly detailed data gathered by modern observatories. This Letter reports the development of a means to verify and validate such models, with particular attention to the context of supernova remnants (SNRs). By using the Nova laser (or other high-energy density facilities), one can produce supersonic plasma ejecta in the laboratory and study their interaction with an ambient, lower density medium. The laboratory system is scaled from the local conditions within young SNRs by keeping constant the quantity velocity x time/spatial dimension. The radiation-hydrodynamic simulations used to establish and optimize the design are reported. A specific experimental implementation is described in which ejecta at similar to 100 km s(-1) are generated, driving a Mach similar to 50 forward shock through a uniform medium. The evolution of the forward and reverse shocks is observed.
C1 Univ Michigan, Ann Arbor, MI 48109 USA.
Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA.
Univ Colorado, Boulder, CO 80309 USA.
RP Drake, RP (reprint author), Univ Michigan, 2455 Hayward St, Ann Arbor, MI 48109 USA.
RI Drake, R Paul/I-9218-2012
OI Drake, R Paul/0000-0002-5450-9844
NR 20
TC 32
Z9 34
U1 1
U2 10
PU UNIV CHICAGO PRESS
PI CHICAGO
PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA
SN 0004-637X
J9 ASTROPHYS J
JI Astrophys. J.
PD JUN 20
PY 1998
VL 500
IS 2
BP L157
EP L161
DI 10.1086/311400
PN 2
PG 5
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA ZX422
UT WOS:000074514200019
ER
PT J
AU Gates, EI
Gyuk, G
Holder, GP
Turner, MS
AF Gates, EI
Gyuk, G
Holder, GP
Turner, MS
TI No need for MACHOs in the halo
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE dark matter; Galaxy : halo; Galaxy : structure
ID GALACTIC HALO; DARK-MATTER; BULGE; STARS; MASS
AB One interpretation of the more than dozen microlensing events seen in the direction of the LMC is a halo population of 0.5 M. MACHOs that accounts for about half of the mass of the Galaxy. Such an interpretation is not without its problems, and we show that LMC microlensing can be explained by a combination of dark components of the thick disk and spheroid in a viable and detailed model of the Galaxy. In our models, the total mass within 50 kpc is similar to 10(11) M.. about 60% of the value based on halo MACHO models, and the estimate for the lens mass is lower, 0.3 M. versus 0.5 M.. The chemical evolution problems associated with the MACHO progenitors are not resolved. However, since the MACHO distribution does not trace the l/r(2) dark halo, which extends significantly beyond 50 kpc, the total baryon mass fraction of the Galaxy is reduced considerably, which lessens the problem.
C1 Adler Planetarium & Astron Museum, Chicago, IL 60605 USA.
Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA.
SISSA, I-34014 Trieste, Italy.
Univ Chicago, Enrico Fermi Inst, Dept Phys, Chicago, IL 60637 USA.
NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA.
RP Gates, EI (reprint author), Adler Planetarium & Astron Museum, Chicago, IL 60605 USA.
NR 30
TC 13
Z9 13
U1 0
U2 0
PU UNIV CHICAGO PRESS
PI CHICAGO
PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA
SN 0004-637X
J9 ASTROPHYS J
JI Astrophys. J.
PD JUN 20
PY 1998
VL 500
IS 2
BP L145
EP L148
DI 10.1086/311406
PN 2
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA ZX422
UT WOS:000074514200016
ER
PT J
AU Alexandratos, SD
Beauvais, R
Duke, JR
Jorgensen, BS
AF Alexandratos, SD
Beauvais, R
Duke, JR
Jorgensen, BS
TI Functionalized polymer foams as metal ion chelating agents with rapid
complexation kinetics
SO JOURNAL OF APPLIED POLYMER SCIENCE
LA English
DT Article
DE crosslinked foams; ion exchange; metal ion separations; phosphonic acids
ID POLYURETHANE FOAM; RESIN; SEPARATIONS; EXTRACTION; COPOLYMER; SORPTION;
MEDIA
AB Foams prepared from vinylbenzyl chloride and crosslinked with divinylbenzene were functionalized with trialkylphosphite and tetralkylvinylidene diphosphonate. It was determined that the foams could be uniformly functionalized. Batch studies with the functionalized foams show that high levels of metal ion complexation can be achieved. Foams may therefore offer an important alternative to beads for rapid complexation reactions due to their highly porous structure. (C) 1998 John Wiley & Sons, Inc.
C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
RP Alexandratos, SD (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA.
NR 23
TC 28
Z9 28
U1 3
U2 11
PU JOHN WILEY & SONS INC
PI NEW YORK
PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA
SN 0021-8995
J9 J APPL POLYM SCI
JI J. Appl. Polym. Sci.
PD JUN 20
PY 1998
VL 68
IS 12
BP 1911
EP 1916
DI 10.1002/(SICI)1097-4628(19980620)68:12<1911::AID-APP3>3.0.CO;2-O
PG 6
WC Polymer Science
SC Polymer Science
GA ZK365
UT WOS:000073313100003
ER
PT J
AU Hino, T
Prausnitz, JM
AF Hino, T
Prausnitz, JM
TI Lattice thermodynamics for aqueous salt-polymer two-phase systems
SO JOURNAL OF APPLIED POLYMER SCIENCE
LA English
DT Article
DE aqueous two-phase systems; electrolyte solutions; liquid-liquid
equilibria; polymer solutions; salting
ID HARD-SPHERE MIXTURES; 2-PHASE SYSTEMS; POLY(ETHYLENE GLYCOL); OSMOTIC
COEFFICIENTS; BINARY-MIXTURES; ELECTROLYTES; SEPARATION; INSTABILITIES;
25-DEGREES-C; EQUILIBRIUM
AB A lattice model is presented to compute salt-induced liquid-liquid phase separation in aqueous polymer solutions. The Gibbs energy of mixing contains an electrostatic contribution given by Fitter's extension of the Debye-Huckel function, and the extended Flory-Huggins theory that uses empirical functions of temperature and composition as binary interaction parameters. Our Flory-Huggins theory assumes complete dissociation of salt into ions, but it does not distinguish between cation and anion; our theory represents the water-salt-polymer mixture as an incompressible ternary system consisting of water, ion, and polymer. In the extended Flory-Huggins theory, the binary interaction parameter between water and ion, and that between water and polymer, are obtained by correlating the observed activity of water in each of the two relevant binary systems. The electrostatic contribution does not contain adjustable parameters. We show that the electrostatic contribution to the Gibbs energy of mixing is responsible for inducing salt-polymer aqueous two-phase systems. Calculated phase diagrams are compared with experiment for aqueous solutions containing polyethylene glycol and a single salt at room temperature. The efficiency of a salt to form salt-polymer aqueous two-phase systems is discussed in terms of ion valence and the interaction parameter between ion and polymer. (C) 1998 John Wiley & Sons, Inc.
C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA.
Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA.
RP Prausnitz, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA.
NR 32
TC 17
Z9 17
U1 2
U2 11
PU JOHN WILEY & SONS INC
PI NEW YORK
PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA
SN 0021-8995
J9 J APPL POLYM SCI
JI J. Appl. Polym. Sci.
PD JUN 20
PY 1998
VL 68
IS 12
BP 2007
EP 2017
DI 10.1002/(SICI)1097-4628(19980620)68:12<2007::AID-APP15>3.0.CO;2-Y
PG 11
WC Polymer Science
SC Polymer Science
GA ZK365
UT WOS:000073313100015
ER
PT J
AU Fukui, Y
Doskey, PV
AF Fukui, Y
Doskey, PV
TI Air-surface exchange of nonmethane organic compounds at a grassland
site: Seasonal variations and stressed emissions
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID CALIFORNIA CENTRAL VALLEY; GAS-PHASE REACTIONS; OXYGENATED HYDROCARBONS;
UNITED-STATES; NATURAL HYDROCARBONS; RATE VARIABILITY; PINE FOREST;
TRACE GASES; ATMOSPHERE; ISOPRENE
AB Emissions of nonmethane organic compounds (NMOCs) were measured by a static enclosure technique at a grassland site in the midwestern United States during the growing seasons over a 2-year period. A mixture of nonmethane hydrocarbons (NMHCs) and oxygenated hydrocarbons (OxHCs) was emitted from the surface at rates exhibiting large seasonal and year-to-year variations. The average emission rate (and standard error) of the total NMOCs around noontime on sunny days during the growing seasons for the 2-year period was 1,300 +/- 170 mu g m(-2) h(-1) (mass of the total NMOCs pet area of enclosed soil surface per hour) or 5.5 +/- 0.9 mu g g(-1) h(-1) (mass of the total NMOCs per mass of dry plant biomass in an enclosure per hour), with about 10% and 70% of the emissions being composed of tentatively identified NMHCs and OxHCs, respectively. Methanol was apparently derived from both the soil and vegetation and exhibited an average emission rate of 460 +/- 73 mu g m(-2) h(-1) (1.4 +/- 0.2 mu g g(-1) h(-1)), which was the largest emission among the NMOCs. The year-to-year variation in the precipitation pattern greatly affected the NMOC emission rates. Emission rates normalized to biomass density exhibited a linear decrease as the growing season progressed. The emission rates of some NMOCs, particularly the OxHCs, from vegetation subjected to hypoxia, frost, and physical stresses were significantly greater than the average values observed at the site. Emissions of monoterpenes (alpha- and beta-pinene, limonene, and myrcene) and cis-3-hexen-1-ol were accelerated during the flowering of the plants and were much greater than those predicted by algorithms that correlated emission rates with temperature. Herbaceous vegetation is estimated to contribute about 40% and 50% of the total NMOC and monoterpene emissions, respectively, in grasslands; the remaining contributions are from woody species within grasslands. Contributions of isoprene emissions from herbaceous vegetation in grasslands are negligible. Grasslands are estimated to contribute about 10% of the total biogenic NMOC emissions in the United States.
C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA.
RP Fukui, Y (reprint author), Argonne Natl Lab, Div Environm Res, 9700 S Cass Ave, Argonne, IL 60439 USA.
EM Paul_Doskey@qmgate.anl.gov
NR 60
TC 54
Z9 56
U1 0
U2 4
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD JUN 20
PY 1998
VL 103
IS D11
BP 13153
EP 13168
DI 10.1029/98JD00924
PG 16
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA ZV631
UT WOS:000074325200006
ER
PT J
AU Kleinman, LI
Daum, PH
Lee, JH
Lee, NY
Weinstein-Lloyd, J
Springston, SR
AF Kleinman, LI
Daum, PH
Lee, JH
Lee, NY
Weinstein-Lloyd, J
Springston, SR
TI Photochemistry of O-3 and related compounds over southern Nova Scotia
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID SOUTHEASTERN UNITED-STATES; PHOTOSTATIONARY STATE; HYDROGEN-PEROXIDE;
MODEL SIMULATIONS; OZONE FORMATION; RURAL SITE; BUDGET; SUMMER;
TROPOSPHERE; ATLANTIC
AB Photochemical model calculations have been performed for air masses encountered by the National Research Council's Twin Otter aircraft during the 1993 summer North Atlantic Regional Experiment (NARE) intensive. These calculations use observed values of O-3, NOy, CO, and hydrocarbons as constraints: NO is determined using the ratio NO/NOy measured from the National Center for Atmospheric Research King Air under comparable circumstances. Measurements over coastal locations indicate photochemically aged air masses with relatively low concentrations of NO and an OH reactivity that is dominated by CO and CH4. Samples over land have higher NO and an OH reactivity that is dominated by isoprene. Ozone production rates and H2O2 concentrations are analyzed using radical budget arguments that are applicable to low NOx conditions. The ozone production rate, P(O-3), is predicted to be proportional to Q (1/2)[NO], where Q is the production rate for free radicals. This relation explains 99% of the variance in P(O-3). Over 90% of the variance is explained by [NO] alone. P(O-3) in the coastal samples is about a factor of 4 lower than previous estimates for the eastern United States. This is a consequence of low [NO] in the air masses that are advected to Nova Scotia.
C1 Brookhaven Natl Lab, Dept Appl Sci, Environm Chem Div, Upton, NY 11973 USA.
NOAA, Aeron Lab, Boulder, CO 80303 USA.
RP Kleinman, LI (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Environm Chem Div, Upton, NY 11973 USA.
EM kleinman@bnl.gov; phdaum@bnl.gov; jaihlee@bnl.gov; ynlee@bnl.gov;
jollyd@bnl.gov; srs@bnl.gov
NR 41
TC 9
Z9 9
U1 1
U2 1
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD JUN 20
PY 1998
VL 103
IS D11
BP 13519
EP 13529
DI 10.1029/97JD01484
PG 11
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA ZV631
UT WOS:000074325200031
ER
PT J
AU Cho, JH
Safar, H
Maley, MP
Willis, JO
Coulter, JY
Steel, DG
Gray, KE
AF Cho, JH
Safar, H
Maley, MP
Willis, JO
Coulter, JY
Steel, DG
Gray, KE
TI Effects of unidirectional and isotropic columnar defects in
Bi2Sr2CaCu2O8 single crystals
SO PHYSICA C
LA English
DT Article
DE Bi2Sr2CaCu2O8 single crystals; columnar defects; irreversibility lines
ID ION IRRADIATED BI2SR2CACU2O8+DELTA; BOSE-GLASS BEHAVIOR; SUPERCONDUCTORS
AB We report the comparative studies of unidirectional columnar defects and isotropic columnar defects in Bi2Sr2CaCu2O8 single crystals. Both types of the columnar defects induce significant enhancements of the irreversibility line and the activation energy. We find the good scalings of the irreversibility lines and the activation energies using the effective matching fields. For the case of isotropic columnar defects, the effective matching field has a large renormalization effect. (C) 1998 Elsevier Science B.V, All rights reserved.
C1 Pusan Natl Univ, RCDAMP, Pusan 609735, South Korea.
Pusan Natl Univ, Dept Phys, Pusan 609735, South Korea.
Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA.
Argonne Natl Lab, Div Sci Mat, Argonne, IL 60349 USA.
RP Cho, JH (reprint author), Pusan Natl Univ, RCDAMP, Jangjun Dong 30, Pusan 609735, South Korea.
NR 13
TC 6
Z9 6
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0921-4534
J9 PHYSICA C
JI Physica C
PD JUN 20
PY 1998
VL 302
IS 2-3
BP 113
EP 118
DI 10.1016/S0921-4534(98)00177-4
PG 6
WC Physics, Applied
SC Physics
GA ZZ526
UT WOS:000074738200003
ER
PT J
AU Morosin, B
Venturini, EL
Dunn, RG
Provencio, PN
Missert, N
Padilla, RR
AF Morosin, B
Venturini, EL
Dunn, RG
Provencio, PN
Missert, N
Padilla, RR
TI Structural and compositional characterization of rubidium-containing
crystals of the Tl-Ba-Ca-Cu-O superconductors
SO PHYSICA C
LA English
DT Article
DE single crystal structure determinations; Tl-Ba-Ca-Cu-O superconductors;
rubidium-containing crystals
ID NEUTRON-DIFFRACTION; SINGLE-CRYSTALS; TL2BA2CACU2O8; SYSTEMS
AB Large single crystals of the Tl-Ba-Ca-Cu-O superconductors have been grown from fluxes including up to 30 mol% Rb of the amount of Tl employed. Various phases have been grown with lattice parameters and superconducting properties similar to crystals grown previously without Rb, though the present crystal plates are usually larger and thicker. There is an increased likelihood of syntactic polycrystal growth as Rb content increases. Successive ion milling combined with energy dispersive X-ray analysis, EDAX, has shown that the Rb is uniformly distributed throughout the plates that are single phase crystals. Precession photographs show sharp diffraction patterns of quality comparable to our Rb-free plates. Magnetically determined Meissner T-c values and transition widths are not significantly altered by Rb substitution. Single crystal X-ray structure refinements have been carried out on several single crystals of each of the four principal phases. In addition various crystal plates have been characterized and studied by transmission electron imaging. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Sandia Natl Labs, Albuquerque, NM 87185 USA.
RP Morosin, B (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA.
NR 18
TC 1
Z9 1
U1 1
U2 1
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0921-4534
J9 PHYSICA C
JI Physica C
PD JUN 20
PY 1998
VL 302
IS 2-3
BP 119
EP 129
DI 10.1016/S0921-4534(98)00202-0
PG 11
WC Physics, Applied
SC Physics
GA ZZ526
UT WOS:000074738200004
ER
PT J
AU Hunt, RD
Beahm, EC
Voronin, GF
AF Hunt, RD
Beahm, EC
Voronin, GF
TI Partial oxygen pressure and temperature effects on the oxygen content of
the Y-Ba-Cu-O melts
SO PHYSICA C
LA English
DT Article
DE oxygen stoichiometry; structural phase transition; phase diagram
ID PSEUDOBINARY BACUO2-YBA2CU3O6.5-YCUO2.5 SYSTEM; PHASE-DIAGRAM;
YBA2CU3O7-X; SUPERCONDUCTORS; STABILITY; LIQUIDUS; OXIDES
AB The oxygen content and phase transition temperatures of equilibrated samples with Y:Ba:Cu:O molar ratios of 1:2:3:n (YBa2Cu3Ox phase) and 1:3,4:n (YBa2Cu3Ox + BaCuO2 phases) were determined with a differential thermal analyzer (DTA), a thermal gravimetric analyzer (TGA) and an electrochemical oxygen analyzer. These Y-Ba-Cu-O melts were studied at partial oxygen pressures that ranged from 1 x 10(5) to 6 Pa and at temperatures from 1200 to 1580 K. The oxygen contents of these melts were determined with hydrogen reduction and the TGA. The oxygen content of the 1:2:3:n melts decreased as the temperature increased and as the partial oxygen pressure decreased. The same pattern for the partial oxygen pressure was observed for the oxygen content in the 1:3,4:n melts. However, at a given partial oxygen pressure, the highest oxygen content in a 1,3:4:n melt was observed at a temperature approximately 100 K above the initial melting temperature. The liquidus temperatures for 1:2:3:n and 1:3:4:n always decreased as the partial oxygen pressures decreased. Finally, the compositions of the melts, which included the formation of YBa3Al2O7.5 in the 1:3:4:n melts, are also discussed. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
Moscow MV Lomonosov State Univ, Dept Chem, Moscow 119899, Russia.
RP Hunt, RD (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
NR 18
TC 3
Z9 3
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0921-4534
J9 PHYSICA C
JI Physica C
PD JUN 20
PY 1998
VL 302
IS 2-3
BP 130
EP 136
DI 10.1016/S0921-4534(98)00201-9
PG 7
WC Physics, Applied
SC Physics
GA ZZ526
UT WOS:000074738200005
ER
PT J
AU Stimson, S
Chen, YJ
Evans, M
Liao, CL
Ng, CY
Hsu, CW
Heimann, P
AF Stimson, S
Chen, YJ
Evans, M
Liao, CL
Ng, CY
Hsu, CW
Heimann, P
TI Rotational-resolved pulsed field ionization photoelectron bands for
H-2(+)(X-2 Sigma(+)(g), v(+) = 0, 2, 9, and 11)
SO CHEMICAL PHYSICS LETTERS
LA English
DT Article
ID QUANTUM-DEFECT THEORY; FINAL-STATE INTERACTIONS; MOLECULAR ION HD+;
ANGULAR-DISTRIBUTION; DIATOMIC-MOLECULES; PHOTO-ELECTRONS;
HIGH-RESOLUTION; GENERAL THEORY; H-2; INTENSITY
AB We present here the assignment and simulation of rotational transitions for the H-2(+) (X-2 Sigma(g)(+), upsilon(+) = 0,2,9 and 11) vibronic bands using the Buckingham-Orr-Sichel (BOS) model. The simulation shows that perturbation of PFI-PE rotational line intensities due to near-resonance autoionization decreases as upsilon(+) increases. Experimental rotational constants for H-2(+) (X-2 Sigma(g)(+), upsilon(+) = 0,2,9 and 11) are determined with higher accuracy than those obtained in previous HeI and NeI photoelectron studies. In agreement with previous experimental and theoretical investigations, only the Delta N=0 and +/-2 rotational branches are observed in the PFI-PE spectrum for H-2. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA.
Iowa State Univ, Dept Chem, Ames, IA 50011 USA.
Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA.
Univ Calif Berkeley, Lawrence Berkeley Lab, Div Accelerator & Fus Res, Adv Light Source, Berkeley, CA 94720 USA.
RP Ng, CY (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA.
EM cyng@ameslab.gov
RI Chen, Yu-Ju/E-9481-2015
NR 38
TC 38
Z9 38
U1 0
U2 3
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0009-2614
J9 CHEM PHYS LETT
JI Chem. Phys. Lett.
PD JUN 19
PY 1998
VL 289
IS 5-6
BP 507
EP 515
DI 10.1016/S0009-2614(98)00412-6
PG 9
WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical
SC Chemistry; Physics
GA ZW236
UT WOS:000074389300014
ER
PT J
AU Strouse, GF
Scott, B
Swanson, BI
Saxena, A
Batistic, I
Gammel, JT
Bishop, AR
AF Strouse, GF
Scott, B
Swanson, BI
Saxena, A
Batistic, I
Gammel, JT
Bishop, AR
TI Tuning dimensionality in low-dimensional electronic materials
SO CHEMICAL PHYSICS LETTERS
LA English
DT Article
ID TETRACYANOQUINODIMETHANE TTF-TCNQ; METAL-COMPLEXES; PHASE-TRANSITIONS;
SUPERCONDUCTORS; SOLIDS; SPINS; HOLES; STATE
AB We demonstrate how dimensionality can be tuned in complex low-dimensional electronic materials via small perturbations in competing molecular forces. The delicate balance between molecular level forces on observed dimensionality in materials is illustrated by the 1-d to 3-d structural reorganization following deuteration of the ancillary ligands in the halogen-bridged transition-metal charge-transfer complex [Pt(en)(2)I-2][Pt(en)(2)]I-2 (PtI) where en denotes ethylenediamine. Specifically, the impact of competing forces on dimensionality is clearly demonstrated by the temperature-dependent phase transitions in perdeuterated PtI (D-PtI), where small changes in inter-and intra-sheet interactions drive mesoscopic structural changes. (C) 1998 Published by Elsevier Science B.V. All rights reserved.
C1 Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA.
Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA.
Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA.
Univ Zagreb, Inst Phys, Zagreb 41001, Croatia.
RP Strouse, GF (reprint author), Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA.
RI Scott, Brian/D-8995-2017
OI Scott, Brian/0000-0003-0468-5396
NR 29
TC 2
Z9 2
U1 1
U2 4
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 JUN 19
PY 1998
VL 289
IS 5-6
BP 559
EP 566
DI 10.1016/S0009-2614(98)00476-X
PG 8
WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical
SC Chemistry; Physics
GA ZW236
UT WOS:000074389300022
ER
PT J
AU Timerbaev, AR
Semenova, OP
Fritz, JS
AF Timerbaev, AR
Semenova, OP
Fritz, JS
TI Improved photometric detection of metal ions by capillary zone
electrophoresis after precapillary complexation
SO JOURNAL OF CHROMATOGRAPHY A
LA English
DT Article; Proceedings Paper
CT International Ion Chromatography Symposium
CY SEP 14-17, 1997
CL SANTA CLARA, CALIFORNIA
DE detection, electrophoresis; metal cations; metal complexes;
cyclohexanediaminetetraacetic acid
ID MASS-SPECTROMETRY; ELEMENTAL SPECIATION; EDTA COMPLEXES; SEPARATION;
MAGNESIUM; ONLINE; CHROMATOGRAPHY; CALCIUM; SAMPLES; SERUM
AB Precapillary reactions using complexing reagents are increasingly being used to carry out separations of metal ions by capillary zone electrophoresis. To compensate for the sensitivity limitations of on-column photometric detection, several approaches were evaluated. Parameters affecting the sensitivity response of a direct detection system, such as the detection wavelength, sample size, applied voltage, and electrolyte concentration, were examined to produce the best possible sensitivity for metal ions complexed with cyclohexane-1,2-diaminetetraacetic acid. Using injection in the electrokinetic mode, a 2-fold increase in detectability over hydrodynamic (gravity) injection was obtained for certain metal analytes that corresponds to the detection limits in the sub-mu g/l range. A characterization and optimization of photometric detection in an indirect format have been conducted. An organic dye, combined with the carrier electrolyte to impart an absorbance background in the visible range and selected with due account for its spectral and electrophoretic characteristics, was found to provide micromolar-level sensitivities. Feasibility of on-line (stacking) sample concentration for metal complexes has also been demonstrated. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Interuniv Inst Agrobiotechnol, Dept Plant Technol, Tulln, Austria.
Iowa State Univ, Dept Chem, Ames, IA 50011 USA.
Iowa State Univ, Ames Lab, Ames, IA 50011 USA.
Russian Acad Sci, Vernadsky Inst Geochem & Analyt Chem, Moscow 117975, Russia.
RP Semenova, OP (reprint author), Interuniv Inst Agrobiotechnol, Dept Plant Technol, Tulln, Austria.
RI Timerbaev, Andrei/G-7530-2016
NR 32
TC 16
Z9 17
U1 1
U2 9
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0021-9673
J9 J CHROMATOGR A
JI J. Chromatogr. A
PD JUN 19
PY 1998
VL 811
IS 1-2
BP 233
EP 239
DI 10.1016/S0021-9673(98)00270-2
PG 7
WC Biochemical Research Methods; Chemistry, Analytical
SC Biochemistry & Molecular Biology; Chemistry
GA ZX012
UT WOS:000074471400023
ER
PT J
AU Fritschy, JM
Johnson, DK
Mohler, H
Rudolph, U
AF Fritschy, JM
Johnson, DK
Mohler, H
Rudolph, U
TI Independent assembly and subcellular targeting of GABA(A)-receptor
subtypes demonstrated in mouse hippocampal and olfactory neurons in vivo
SO NEUROSCIENCE LETTERS
LA English
DT Article
DE GABA(A)-receptor subunit assembly; subunit gene; chromosomal deletion; p
locus; immunofluorescent staining; mouse mutants
ID RECOMBINANT GABA(A) RECEPTOR; AMINOBUTYRIC-ACID RECEPTOR; A RECEPTORS;
SUBUNITS; LOCALIZATION; MICE; BETA(3)-SUBUNIT; STOICHIOMETRY; CELLS;
GENE
AB The ability of neurons to display more than a single GABA(A)-receptor subtype per cell requires intricate targeting mechanisms. Analysis by confocal laser scanning microscopy revealed that the alpha 2- and alpha 5-subunits differed strikingly in their subcellular distribution in hippocampal pyramidal cells and olfactory bulb granule cells, while the distribution of the gamma 2-subunit was rather uniform. In mutant mice lacking the alpha 5-subunit gene due to a chromosomal deletion, the absence of the alpha 5-subunit was accompanied by a corresponding decrease of the gamma 2-subunit immunoreactivity. In striking contrast, the subcellular distribution of the gamma 2-subunit was unchanged in these mutant mice. These findings indicate that the assembly of distinct GABA(A)-receptor subtypes in the same neuron is regulated independently. Furthermore, the alpha-subunit is a prime candidate for providing domains which direct subcellular targeting. Published by Elsevier Science Ireland Ltd.
C1 Univ Zurich, Inst Pharmacol, CH-8057 Zurich, Switzerland.
Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA.
RP Rudolph, U (reprint author), Univ Zurich, Inst Pharmacol, Winterthurerstr 190, CH-8057 Zurich, Switzerland.
EM rudolph@pharma.unizh.ch
NR 17
TC 70
Z9 76
U1 0
U2 4
PU ELSEVIER SCI IRELAND LTD
PI CLARE
PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE,
IRELAND
SN 0304-3940
J9 NEUROSCI LETT
JI Neurosci. Lett.
PD JUN 19
PY 1998
VL 249
IS 2-3
BP 99
EP 102
DI 10.1016/S0304-3940(98)00397-8
PG 4
WC Neurosciences
SC Neurosciences & Neurology
GA ZZ591
UT WOS:000074745500008
PM 9682826
ER
PT J
AU Korber, B
Theiler, J
Wolinsky, S
AF Korber, B
Theiler, J
Wolinsky, S
TI Limitations of a molecular clock applied to considerations of the origin
of HIV-1
SO SCIENCE
LA English
DT Editorial Material
ID IMMUNODEFICIENCY-VIRUS TYPE-1; REVERSE-TRANSCRIPTASE; ENVELOPE GENES;
GAG GENES; SEQUENCE; ISOLATE; RECOMBINATION; TRANSMISSION; INFECTIONS;
EVOLUTION
C1 Northwestern Univ, Sch Med, Dept Med, Chicago, IL 60611 USA.
Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp NIS2, Los Alamos, NM 87545 USA.
Univ Calif Los Alamos Natl Lab, Theoret Div T10, Los Alamos, NM 87545 USA.
RP Wolinsky, S (reprint author), Northwestern Univ, Sch Med, Dept Med, Chicago, IL 60611 USA.
RI Wolinsky, Steven/B-2893-2012;
OI Wolinsky, Steven/0000-0002-9625-6697; Korber, Bette/0000-0002-2026-5757
FU NIAID NIH HHS [3-Y01-AI-70001-13]; NICHD NIH HHS [R01-HD-31756]; PHS HHS
[Y1-A1-4058-03]
NR 64
TC 64
Z9 64
U1 3
U2 7
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 JUN 19
PY 1998
VL 280
IS 5371
BP 1868
EP 1871
DI 10.1126/science.280.5371.1868
PG 4
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA ZV618
UT WOS:000074323800041
PM 9669945
ER
PT J
AU Owens, DK
Edwards, DM
Shachter, RD
AF Owens, DK
Edwards, DM
Shachter, RD
TI Population effects of preventive and therapeutic HIV vaccines in early-
and late-stage epidemics
SO AIDS
LA English
DT Article
DE HIV; AIDS; AIDS vaccines; HIV-1; HIV seroprevalence
ID HUMAN-IMMUNODEFICIENCY-VIRUS; FRANCISCO MENS HEALTH; SAN-FRANCISCO;
RECOMBINANT GP160; BISEXUAL MEN; INFECTION; AIDS; IMMUNOGENICITY;
TRANSMISSION; SAFETY
AB Objective: To evaluate the population effects of potential preventive and therapeutic vaccines in early- and late-stage epidemics in a population of homosexual men.
Methods: An epidemic model was used that simulated the course of the epidemic for a population of homosexual men in San Francisco, California. Vaccine programs were evaluated by the number of cases of HIV averted, the effect on the prevalence of HIV, and by the gain in quality-adjusted life years (QALY) for the total population.
Results: In the model, a preventive vaccine prevented 3877 cases of HIV infection during a 20-year period, reduced the projected prevalence of HIV infection from 12 to 7% in a late-stage epidemic, and gained 15 908 QALY. A therapeutic vaccine that did not affect the infectivity of vaccine recipients increased the number of cases of HIV infection by 210, resulted in a slight increase in the prevalence of HIV infection from 12 to 15% in a late-stage epidemic, and gained 8854 QALY. If therapeutic vaccines reduced infectivity, their use could produce net gains of QALY in the population that were similar to gains from the use of preventive vaccines. In an early-stage epidemic, the advantage of a preventive vaccine program relative to a therapeutic vaccine program was markedly enhanced.
Conclusions: Both preventive and therapeutic vaccine programs provided substantial benefit, but their relative merit depended on which outcome measures were assessed. Evaluation of HIV vaccine programs based solely on cases averted or on prevalence of HIV in the population underestimates the benefit associated with therapeutic vaccine programs. The effect of a therapeutic HIV vaccine on the epidemic outcomes depended markedly on whether the therapeutic vaccine reduced the infectivity of the vaccine recipient. The relative merits of preventive and therapeutic vaccines depend on the stage of the epidemic. Field vaccine trials should evaluate correlates of infectivity, such as HIV viral load. HIV vaccine implementation strategies should be tailored to the dynamics of the epidemic in specific populations. (C) 1998 Lippincott-Raven Publishers.
C1 VA Palo Alto Hlth Care Syst, Sect Gen Med 111A, Palo Alto, CA 94304 USA.
Stanford Univ, Dept Med, Sect Med Informat, Stanford, CA 94305 USA.
Stanford Univ, Dept Hlth Res & Policy, Stanford, CA 94305 USA.
Stanford Univ, Dept Engn Econ Syst, Stanford, CA 94305 USA.
Sandia Natl Labs, Livermore, CA USA.
RP Owens, DK (reprint author), VA Palo Alto Hlth Care Syst, Sect Gen Med 111A, 3801 Miranda Ave, Palo Alto, CA 94304 USA.
FU PHS HHS [R-01-09531-01A2]
NR 37
TC 20
Z9 20
U1 1
U2 1
PU LIPPINCOTT WILLIAMS & WILKINS
PI PHILADELPHIA
PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA
SN 0269-9370
J9 AIDS
JI Aids
PD JUN 18
PY 1998
VL 12
IS 9
BP 1057
EP 1066
DI 10.1097/00002030-199809000-00013
PG 10
WC Immunology; Infectious Diseases; Virology
SC Immunology; Infectious Diseases; Virology
GA 102HN
UT WOS:000074918500014
PM 9662203
ER
PT J
AU Farrell, JT
Taatjes, CA
AF Farrell, JT
Taatjes, CA
TI Infrared frequency-modulation probing of Cl+C3H4 (allene, propyne)
reactions: Kinetics of HCl production from 292 to 850 K
SO JOURNAL OF PHYSICAL CHEMISTRY A
LA English
DT Article
ID THERMAL UNIMOLECULAR REACTIONS; COLLISION RATE CONSTANTS; CL ATOM
REACTIONS; CHLORINE ATOMS; PRESSURE-DEPENDENCE; ETHYL RADICALS;
LINE-SHAPES; RECOMBINATION; SPECTROSCOPY; C2H4
AB Absolute rate coefficients for the reactions of chlorine atoms with allene (propadiene, H2C=C=CH2) and propyne (HC=C-CH3) have been measured as a function of temperature (292-850 K) and pressure (4-10 Torr) with a laser photolysis/CW infrared long path absorption technique. The reactions are initiated via pulsed laser photolysis of Cl-2 and monitored through CW infrared frequency-modulation spectroscopy of the HCl product. At room temperature (292 K), the reaction of Cl with allene proceeds almost exclusively through addition, with little HCl generated through either abstraction or elimination. HCl production increases with temperature, and becomes unity at T greater than or equal to 800 K. Quantitative HCl yield measurements allow the contributions of addition and abstraction/elimination to the total rate to be determined. The rate coefficient for HCl production is described between 292 and 850 K by the Arrhenius expression, k(metathesis)(allene)(T) = (3.7 +/- 1.7) x 10(-10) exp-[-(1671 +/- 286)/T] cm(3) molecule(-1) s(-1), (all error bars +/-2 sigma precision only). In contrast with the Cl + allene reaction, both addition and metathesis appear to be important channels in the reaction of Cl + propyne near room temperature. The reactions display biexponential HCl time profiles at T less than or equal to 400 K, but at T greater than or equal to 500 K, only single-exponential evolution is observed. The HCl yield at 293 K is approximate to 70% and reaches unity at T greater than or equal to 500 K. A fit of the rate coefficient for HCl production between 400 less than or equal to T less than or equal to 800 K to standard Arrhenius form gives k(metathesis)(propyne)(T) = (3.7 +/- 1.0) x 10(-11) exp[-(685 +/- 151)/T] cm(3) molecule(-1) s(-1). The data over the whole 292-800 K temperature range exhibit curvature and are better fit by the modified Arrhenius expression (with the temperature exponent fixed at 2) k(metathesis)(propyne)(T) = (1.25 +/- 0.21) x 10(-12) (T/298)(2) exp[(500 +/- 93)/T] cm(3) molecule(-1) s(-1) (+/-2 sigma precision). Preliminary measurements are also presented for Cl + isobutene between 300 and 700 K, which were required to comet for the small butene contamination in the propyne, Measurements carried out in Ar buffer indicate that vibrationally excited HCl is formed with both allene and propyne and allow an estimate to be made for k(VET), the HCl (upsilon = 1) + C3H4 vibrational relaxation rate coefficient. In the Cl + allene reaction, approximately half (f = 0.42 +/- 0.10) of the HCl is formed in upsilon = 1, and k(VET) = (2.8 +/- 0.4) x 10(-12) cm(3) molecule(-1) s(-1); with propyne, the corresponding values are f = 0.55 +/- 0.09 and k(VET) = (8.6 +/- 3.6) x 10(-12) cm(3) molecule(-1) s(-1). The qualitatively different dynamics for Cl + aliene vs propyne can be attributed to formation of a resonantly stabilized radical with aliene (chloroallyl), which greatly enhances the addition rate. Comparisons are also made with recent ab initio calculations of energies and transition states for the Cl + C3H4 reactions.
C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA.
RP Taatjes, CA (reprint author), Sandia Natl Labs, Combust Res Facil, Mail Stop 9055, Livermore, CA 94551 USA.
NR 48
TC 29
Z9 29
U1 0
U2 3
PU AMER CHEMICAL SOC
PI WASHINGTON
PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA
SN 1089-5639
J9 J PHYS CHEM A
JI J. Phys. Chem. A
PD JUN 18
PY 1998
VL 102
IS 25
BP 4846
EP 4856
DI 10.1021/jp981265r
PG 11
WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical
SC Chemistry; Physics
GA ZV964
UT WOS:000074360000012
ER
PT J
AU Arkani-Hamed, N
Dimopoulos, S
Dvali, G
AF Arkani-Hamed, N
Dimopoulos, S
Dvali, G
TI The hierarchy problem and new dimensions at a millimeter
SO PHYSICS LETTERS B
LA English
DT Article
ID STRINGS
AB We propose a new framework for solving the hierarchy problem which does not rely on either supersymmetry or technicolor. In this framework, the gravitational and gauge interactions become united at the weak scale, which we take as the only fundamental short distance scale in nature. The observed weakness of gravity on distances greater than or similar to 1 mm is due to the existence of n greater than or equal to 2 new compact spatial dimensions large compared to the weak scale. The Planck scale M-Pl similar to G(N)(-1/2) is not a fundamental scale; its enormity is simply a consequence of the large size of the new dimensions. While gravitons can freely propagate in the new dimensions, at sub-weak energies the Standard Model (SM) fields must be localized to a 4-dimensional manifold of weak scale "thickness" in the extra dimensions. This picture leads to a number of striking signals for accelerator and laboratory experiments. For the case of n = 2 new dimensions, planned sub-millimeter measurements of gravity may observe the transition from 1/r(2) --> 1/r(4) Newtonian gravitation. For any number of new dimensions, the LHC and NLC could observe strong quantum gravitational interactions. Furthermore, SM particles can be kicked off our 4 dimensional manifold into the new dimensions, carrying away energy, and leading to an abrupt decrease in events with high transverse momentum p(T) greater than or similar to TeV. For certain compact manifolds, such particles will keep circling in the extra dimensions, periodically returning, colliding with and depositing energy to our four dimensional vacuum with frequencies of similar to 10(12) Hz or larger. As a concrete illustration, we construct a model with SM fields localized on the 4-dimensional throat of a vortex in 6 dimensions, with a Pati-Salam gauge symmetry SU(4) X SU(2) X SU(2) in the bulk. (C) 1998 Published by Elsevier Science B.V. All rights reserved.
C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
Stanford Univ, Dept Phys, Stanford, CA 94305 USA.
Int Ctr Theoret Phys, I-34100 Trieste, Italy.
RP Arkani-Hamed, N (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA.
NR 15
TC 4467
Z9 4489
U1 25
U2 150
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 JUN 18
PY 1998
VL 429
IS 3-4
BP 263
EP 272
DI 10.1016/S0370-2693(98)00466-3
PG 10
WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields
SC Astronomy & Astrophysics; Physics
GA ZZ088
UT WOS:000074694500008
ER
PT J
AU Graesser, M
Morariu, B
AF Graesser, M
Morariu, B
TI A non-perturbative non-renormalization theorem for the Wilsonian gauge
couplings in supersymmetric theories
SO PHYSICS LETTERS B
LA English
DT Article
AB We present a direct proof that the holomorphic Wilsonian beta-function of a renormalizable asymptotically free supersymmetric gauge theory with an arbitrary semi-simple gauge group, matter content, and renormalizable superpotential is exhausted at 1-loop with no higher loops and no non-perturbative contributions. This is a non-perturbative extension of the well known result of Shifman and Vainshtein. (C) 1998 Published by Elsevier Science B.V. All rights reserved.
C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.
Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA.
RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.
EM graesser@thsrv.lbl.gov; bogdan@physics.berkeley.edu
NR 9
TC 7
Z9 7
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0370-2693
EI 1873-2445
J9 PHYS LETT B
JI Phys. Lett. B
PD JUN 18
PY 1998
VL 429
IS 3-4
BP 313
EP 318
DI 10.1016/S0370-2693(98)00485-7
PG 6
WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields
SC Astronomy & Astrophysics; Physics
GA ZZ088
UT WOS:000074694500014
ER
PT J
AU Acciarri, M
Adriani, O
Aguilar-Benitez, M
Ahlen, S
Alcaraz, J
Alemanni, G
Allaby, J
Aloisio, A
Alviggi, MG
Ambrosi, G
Anderhub, H
Andreev, VP
Angelescu, T
Anselmo, F
Arefiev, A
Azemoon, T
Aziz, T
Bagnaia, P
Baksay, L
Ball, RC
Banerjee, S
Banerjee, S
Banicz, K
Barczyk, A
Barillere, R
Barone, L
Bartalini, P
Baschirotto, A
Basile, M
Battiston, R
Bay, A
Becattini, F
Becker, U
Behner, F
Berdugo, J
Berges, P
Bertucci, B
Betev, BL
Bhattacharya, S
Biasini, M
Biland, A
Bilei, GM
Blaising, JJ
Blyth, SC
Bobbink, GJ
Bock, R
Bohm, A
Boldizsar, L
Borgia, B
Bourilkov, D
Bourquin, M
Boutigny, D
Braccini, S
Branson, JG
Brigljevic, V
Brock, IC
Buffini, A
Buijs, A
Burger, JD
Burger, WJ
Busenitz, J
Cai, XD
Campanelli, M
Capell, M
Romeo, GC
Carlino, G
Cartacci, AM
Casaus, J
Castellini, G
Cavallari, F
Cavallo, N
Cecchi, C
Cerrada, M
Cesaroni, F
Chamizo, M
Chang, YH
Chaturvedi, UK
Chekanov, SV
Chemarin, M
Chen, A
Chen, G
Chen, GM
Chen, HF
Chen, HS
Chen, M
Chiefari, G
Chein, CY
Cifarelli, L
Cindolo, F
Civinini, C
Clare, I
Clare, R
Cohn, HO
Coignet, G
Colijn, AP
Colino, N
Costantini, S
Cotorobai, F
de la Cruz, B
Csilling, A
Dai, TS
D'Alessandro, R
de Asmundis, R
Degre, A
Deiters, K
Denes, P
DeNotaristefani, F
DiBitonto, D
Diemoz, M
van Dierendonck, D
Di Lodovico, F
Dionisi, C
Dittmar, M
Dominguez, A
Doria, A
Dova, MT
Drago, E
Duchesneau, D
Duinker, P
Duran, I
Dutta, S
Easo, S
Efremenko, Y
El Mamouni, H
Engler, A
Eppling, FJ
Erne, FC
Ernenwein, JP
Extermann, P
Fabre, M
Faccini, R
Falciano, S
Favara, A
Fay, J
Fedin, O
Felcini, M
Fenyi, B
Ferguson, T
Ferroni, F
Fesefeldt, H
Fiandrini, E
Field, JH
Filthaut, F
Fisher, PH
Fisk, I
Forconi, G
Fredj, L
Freudenreich, K
Furetta, C
Galaktionov, Y
Ganguli, SN
Garcia-Abia, P
Gau, SS
Gentile, S
Gerald, J
Gheordanescu, N
Giagu, S
Goldfarb, S
Goldstein, J
Gong, ZF
Gougas, A
Gratta, G
Gruenewald, MW
Gupta, VK
Gurtu, A
Gutay, LJ
Haas, D
Hartmann, B
Hasan, A
Hatzifotiadou, D
Hebbeker, T
Herve, A
Hirschfelder, J
van Hoek, WC
Hofer, H
Hong, SJ
Hoorani, H
Hou, SR
Hu, G
Innocente, V
Jenkes, K
Jin, BN
Jones, LW
de Jong, P
Josa-Mutuberria, I
Kasser, A
Khan, RA
Kamrad, D
Kamyshkov, Y
Kapustinsky, JS
Karyotakis, Y
Kaur, M
Kienzle-Focacci, MN
Kim, D
Kim, DH
Kim, JK
Kim, SC
Kim, YG
Kinnison, WW
Kirkby, A
Kirkby, D
Kirkby, J
Kiss, D
Kittel, W
Klimentov, A
Konig, AC
Kopp, A
Korolko, I
Koutsenko, V
Kraemer, RW
Krenz, W
Kunin, A
Lacentre, P
de Guevara, PL
Lavorato, A
Lebeau, M
Lebedev, A
Lebrun, P
Lecomte, P
Lecoq, P
Le Coultre, P
Lee, HJ
Leggett, C
Le Goff, JM
Leiste, R
Leonardi, E
Levtchenko, P
Li, C
Lin, CH
Lin, WT
Linde, FL
Lista, L
Liu, ZA
Lohmann, W
Longo, E
Lu, W
Lu, YS
Lubelsmeyer, K
Luci, C
Luckey, D
Luminari, L
Lustermann, W
Ma, WG
Maity, M
Majumder, G
Malgeri, L
Malinin, A
Mana, C
Mangeol, D
Mangla, S
Marchesini, P
Marin, A
Martin, JP
Marzano, F
Massaro, GGG
McNally, D
Mele, S
Merola, L
Meschini, M
Metzger, WJ
von der Mey, M
Mi, Y
Migani, D
Mihul, A
van Mil, AJW
Milcent, H
Mirabelli, G
Mnich, J
Molnar, P
Monteleoni, B
Moore, R
Morganti, S
Moulik, T
Mount, R
Muheim, F
Muijs, AJM
Nahn, S
Napolitano, M
Nessi-Tedaldi, F
Newman, H
Niessen, T
Nippe, A
Nisati, A
Nowak, H
Oh, YD
Opitz, H
Organtini, G
Ostonen, R
Palit, S
Palomares, C
Pandoulas, D
Paoletti, S
Paolucci, P
Park, HK
Park, IH
Pascale, G
Passaleva, G
Patricelli, S
Paul, T
Pauluzzi, M
Paus, C
Pauss, F
Peach, D
Pei, YJ
Pensotti, S
Perret-Gallix, D
Petersen, B
Petrak, S
Pevsner, A
Piccolo, D
Pieri, M
Piroue, PA
Pistolesi, E
Plyaskin, V
Pohl, M
Pojidaev, V
Postema, H
Produit, N
Prokofiev, D
Quartieri, J
Rahal-Callot, G
Raja, N
Rancoita, PG
Rattaggi, M
Raven, G
Razis, P
Read, K
Ren, D
Rescigno, M
Reucroft, S
van Rhee, T
Riemann, S
Riles, K
Rind, O
Robohm, A
Rodin, J
Roe, BP
Romero, L
Rosier-Lees, S
Rosselet, P
van Rossum, W
Roth, S
Rubio, JA
Ruschmeier, D
Rykaczewski, H
Salicio, J
Sanchez, E
Sanders, MP
Sarakinos, ME
Sarkar, S
Sauvage, G
Schafer, C
Schegelsky, V
Schmidt-Kaerst, S
Schmitz, D
Schneegans, M
Scholz, N
Schopper, H
Schotanus, DJ
Schwenke, J
Schwering, G
Sciacca, C
Sciarrino, D
Servoli, L
Shevchenko, S
Shivarov, N
Shoutko, V
Shukla, J
Shumilov, E
Shvorob, A
Siedenburg, T
Son, D
Soulimov, V
Smith, B
Spillantini, P
Steuer, M
Stickland, DP
Stone, H
Stoyanov, B
Straessner, A
Sudhakar, K
Sultanov, G
Sun, LZ
Susinno, GF
Suter, H
Swain, JD
Tang, XW
Tauscher, L
Taylor, L
Ting, SCC
Ting, SM
Tonwar, SC
Toth, J
Tully, C
Tuchscherer, H
Tung, KL
Uchida, Y
Ulbricht, J
Uwer, U
Valente, E
Vesztergombi, G
Vetlitsky, I
Viertel, G
Vivargent, M
Vlachos, S
Volkert, R
Vogel, H
Vogt, H
Vorobiev, I
Vorobyov, AA
Vorvolakos, A
Wadhwa, M
Wallraff, W
Wang, JC
Wang, XL
Wang, ZM
Weber, A
Wu, SX
Wynhoff, S
Xu, J
Xu, ZZ
Yang, BZ
Yang, CG
Yao, XY
Ye, JB
Yeh, SC
You, JM
Zalite, A
Zalite, Y
Zemp, P
Zeng, Y
Zhang, Z
Zhang, ZP
Zhou, B
Zhou, Y
Zhu, GY
Zhu, RY
Zichichi, A
Ziegler, F
AF Acciarri, M
Adriani, O
Aguilar-Benitez, M
Ahlen, S
Alcaraz, J
Alemanni, G
Allaby, J
Aloisio, A
Alviggi, MG
Ambrosi, G
Anderhub, H
Andreev, VP
Angelescu, T
Anselmo, F
Arefiev, A
Azemoon, T
Aziz, T
Bagnaia, P
Baksay, L
Ball, RC
Banerjee, S
Banerjee, S
Banicz, K
Barczyk, A
Barillere, R
Barone, L
Bartalini, P
Baschirotto, A
Basile, M
Battiston, R
Bay, A
Becattini, F
Becker, U
Behner, F
Berdugo, J
Berges, P
Bertucci, B
Betev, BL
Bhattacharya, S
Biasini, M
Biland, A
Bilei, GM
Blaising, JJ
Blyth, SC
Bobbink, GJ
Bock, R
Bohm, A
Boldizsar, L
Borgia, B
Bourilkov, D
Bourquin, M
Boutigny, D
Braccini, S
Branson, JG
Brigljevic, V
Brock, IC
Buffini, A
Buijs, A
Burger, JD
Burger, WJ
Busenitz, J
Cai, XD
Campanelli, M
Capell, M
Romeo, GC
Carlino, G
Cartacci, AM
Casaus, J
Castellini, G
Cavallari, F
Cavallo, N
Cecchi, C
Cerrada, M
Cesaroni, F
Chamizo, M
Chang, YH
Chaturvedi, UK
Chekanov, SV
Chemarin, M
Chen, A
Chen, G
Chen, GM
Chen, HF
Chen, HS
Chen, M
Chiefari, G
Chein, CY
Cifarelli, L
Cindolo, F
Civinini, C
Clare, I
Clare, R
Cohn, HO
Coignet, G
Colijn, AP
Colino, N
Costantini, S
Cotorobai, F
de la Cruz, B
Csilling, A
Dai, TS
D'Alessandro, R
de Asmundis, R
Degre, A
Deiters, K
Denes, P
DeNotaristefani, F
DiBitonto, D
Diemoz, M
van Dierendonck, D
Di Lodovico, F
Dionisi, C
Dittmar, M
Dominguez, A
Doria, A
Dova, MT
Drago, E
Duchesneau, D
Duinker, P
Duran, I
Dutta, S
Easo, S
Efremenko, Y
El Mamouni, H
Engler, A
Eppling, FJ
Erne, FC
Ernenwein, JP
Extermann, P
Fabre, M
Faccini, R
Falciano, S
Favara, A
Fay, J
Fedin, O
Felcini, M
Fenyi, B
Ferguson, T
Ferroni, F
Fesefeldt, H
Fiandrini, E
Field, JH
Filthaut, F
Fisher, PH
Fisk, I
Forconi, G
Fredj, L
Freudenreich, K
Furetta, C
Galaktionov, Y
Ganguli, SN
Garcia-Abia, P
Gau, SS
Gentile, S
Gerald, J
Gheordanescu, N
Giagu, S
Goldfarb, S
Goldstein, J
Gong, ZF
Gougas, A
Gratta, G
Gruenewald, MW
Gupta, VK
Gurtu, A
Gutay, LJ
Haas, D
Hartmann, B
Hasan, A
Hatzifotiadou, D
Hebbeker, T
Herve, A
Hirschfelder, J
van Hoek, WC
Hofer, H
Hong, SJ
Hoorani, H
Hou, SR
Hu, G
Innocente, V
Jenkes, K
Jin, BN
Jones, LW
de Jong, P
Josa-Mutuberria, I
Kasser, A
Khan, RA
Kamrad, D
Kamyshkov, Y
Kapustinsky, JS
Karyotakis, Y
Kaur, M
Kienzle-Focacci, MN
Kim, D
Kim, DH
Kim, JK
Kim, SC
Kim, YG
Kinnison, WW
Kirkby, A
Kirkby, D
Kirkby, J
Kiss, D
Kittel, W
Klimentov, A
Konig, AC
Kopp, A
Korolko, I
Koutsenko, V
Kraemer, RW
Krenz, W
Kunin, A
Lacentre, P
de Guevara, PL
Lavorato, A
Lebeau, M
Lebedev, A
Lebrun, P
Lecomte, P
Lecoq, P
Le Coultre, P
Lee, HJ
Leggett, C
Le Goff, JM
Leiste, R
Leonardi, E
Levtchenko, P
Li, C
Lin, CH
Lin, WT
Linde, FL
Lista, L
Liu, ZA
Lohmann, W
Longo, E
Lu, W
Lu, YS
Lubelsmeyer, K
Luci, C
Luckey, D
Luminari, L
Lustermann, W
Ma, WG
Maity, M
Majumder, G
Malgeri, L
Malinin, A
Mana, C
Mangeol, D
Mangla, S
Marchesini, P
Marin, A
Martin, JP
Marzano, F
Massaro, GGG
McNally, D
Mele, S
Merola, L
Meschini, M
Metzger, WJ
von der Mey, M
Mi, Y
Migani, D
Mihul, A
van Mil, AJW
Milcent, H
Mirabelli, G
Mnich, J
Molnar, P
Monteleoni, B
Moore, R
Morganti, S
Moulik, T
Mount, R
Muheim, F
Muijs, AJM
Nahn, S
Napolitano, M
Nessi-Tedaldi, F
Newman, H
Niessen, T
Nippe, A
Nisati, A
Nowak, H
Oh, YD
Opitz, H
Organtini, G
Ostonen, R
Palit, S
Palomares, C
Pandoulas, D
Paoletti, S
Paolucci, P
Park, HK
Park, IH
Pascale, G
Passaleva, G
Patricelli, S
Paul, T
Pauluzzi, M
Paus, C
Pauss, F
Peach, D
Pei, YJ
Pensotti, S
Perret-Gallix, D
Petersen, B
Petrak, S
Pevsner, A
Piccolo, D
Pieri, M
Piroue, PA
Pistolesi, E
Plyaskin, V
Pohl, M
Pojidaev, V
Postema, H
Produit, N
Prokofiev, D
Quartieri, J
Rahal-Callot, G
Raja, N
Rancoita, PG
Rattaggi, M
Raven, G
Razis, P
Read, K
Ren, D
Rescigno, M
Reucroft, S
van Rhee, T
Riemann, S
Riles, K
Rind, O
Robohm, A
Rodin, J
Roe, BP
Romero, L
Rosier-Lees, S
Rosselet, P
van Rossum, W
Roth, S
Rubio, JA
Ruschmeier, D
Rykaczewski, H
Salicio, J
Sanchez, E
Sanders, MP
Sarakinos, ME
Sarkar, S
Sauvage, G
Schafer, C
Schegelsky, V
Schmidt-Kaerst, S
Schmitz, D
Schneegans, M
Scholz, N
Schopper, H
Schotanus, DJ
Schwenke, J
Schwering, G
Sciacca, C
Sciarrino, D
Servoli, L
Shevchenko, S
Shivarov, N
Shoutko, V
Shukla, J
Shumilov, E
Shvorob, A
Siedenburg, T
Son, D
Soulimov, V
Smith, B
Spillantini, P
Steuer, M
Stickland, DP
Stone, H
Stoyanov, B
Straessner, A
Sudhakar, K
Sultanov, G
Sun, LZ
Susinno, GF
Suter, H
Swain, JD
Tang, XW
Tauscher, L
Taylor, L
Ting, SCC
Ting, SM
Tonwar, SC
Toth, J
Tully, C
Tuchscherer, H
Tung, KL
Uchida, Y
Ulbricht, J
Uwer, U
Valente, E
Vesztergombi, G
Vetlitsky, I
Viertel, G
Vivargent, M
Vlachos, S
Volkert, R
Vogel, H
Vogt, H
Vorobiev, I
Vorobyov, AA
Vorvolakos, A
Wadhwa, M
Wallraff, W
Wang, JC
Wang, XL
Wang, ZM
Weber, A
Wu, SX
Wynhoff, S
Xu, J
Xu, ZZ
Yang, BZ
Yang, CG
Yao, XY
Ye, JB
Yeh, SC
You, JM
Zalite, A
Zalite, Y
Zemp, P
Zeng, Y
Zhang, Z
Zhang, ZP
Zhou, B
Zhou, Y
Zhu, GY
Zhu, RY
Zichichi, A
Ziegler, F
TI Local multiplicity fluctuations in hadronic Z decay
SO PHYSICS LETTERS B
LA English
DT Article
ID HIGH-ENERGY COLLISIONS; QCD JETS; INTERMITTENCY; DETECTOR; ANNIHILATION;
CONSTRUCTION; DIMENSIONS; SIMULATION; MOMENTS; Z(0)
AB Local multiplicity fluctuations in hadronic Z decays are studied using the L3 detector at LEP. Bunching parameters are used for the first time in addition to the normalised factorial moment method. The bunching parameters directly demonstrate that the fluctuations in rapidity are multifractal. Monte Carlo models show agreement with the data, reproducing the trend, although not always the magnitude, of the factorial moments and bunching parameters. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Ist Nazl Fis Nucl, I-20133 Milan, Italy.
Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany.
Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany.
NIKHEF, Natl Inst High Energy Phys, NL-1009 DB Amsterdam, Netherlands.
Univ Amsterdam, NL-1009 DB Amsterdam, Netherlands.
Univ Michigan, Ann Arbor, MI 48109 USA.
Lab Annecy Le Vieux Phys Particules, CNRS, IN2P3, F-74941 Annecy Le Vieux, France.
Johns Hopkins Univ, Baltimore, MD 21218 USA.
Univ Basel, Inst Phys, CH-4056 Basel, Switzerland.
Inst High Energy Phys, Beijing 100039, Peoples R China.
Humboldt Univ, D-10099 Berlin, Germany.
Univ Bologna, I-40126 Bologna, Italy.
Ist Nazl Fis Nucl, I-40126 Bologna, Italy.
Tata Inst Fundamental Res, Bombay 400085, Maharashtra, India.
Boston Univ, Boston, MA 02215 USA.
Northeastern Univ, Boston, MA 02115 USA.
Inst Atom Phys, R-76900 Bucharest, Romania.
Univ Bucharest, R-76900 Bucharest, Romania.
Hungarian Acad Sci, Cent Res Inst Phys, H-1525 Budapest 114, Hungary.
MIT, Cambridge, MA 02139 USA.
Ist Nazl Fis Nucl, I-50125 Florence, Italy.
Univ Florence, I-50125 Florence, Italy.
CERN, European Lab Particle Phys, CH-1211 Geneva 23, Switzerland.
FBLJA Project, World Lab, CH-1211 Geneva 23, Switzerland.
Univ Geneva, CH-1211 Geneva 4, Switzerland.
Univ Sci & Technol China, Hefei 230029, Anhui, Peoples R China.
Res Inst High Energy Phys, SEFT, SF-00014 Helsinki, Finland.
Univ Lausanne, CH-1015 Lausanne, Switzerland.
Ist Nazl Fis Nucl, I-73100 Lecce, Italy.
Univ Lecce, I-73100 Lecce, Italy.
Los Alamos Natl Lab, Los Alamos, NM 87544 USA.
Univ Lyon 1, CNRS, IN2P3, Inst Phys Nucl Lyon, F-69622 Villeurbanne, France.
CIEMAT, E-28040 Madrid, Spain.
Inst Theoret & Expt Phys, Moscow 117259, Russia.
Ist Nazl Fis Nucl, I-80125 Naples, Italy.
Univ Naples Federico II, I-80125 Naples, Italy.
Univ Cyprus, Dept Nat Sci, Nicosia, Cyprus.
Catholic Univ Nijmegen, NL-6525 ED Nijmegen, Netherlands.
Natl Inst Nucl Phys & High Energy Phys, NL-6525 ED Nijmegen, Netherlands.
Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
CALTECH, Pasadena, CA 91125 USA.
Ist Nazl Fis Nucl, I-06100 Perugia, Italy.
Univ Perugia, I-06100 Perugia, Italy.
Carnegie Mellon Univ, Pittsburgh, PA 15213 USA.
Princeton Univ, Princeton, NJ 08544 USA.
Ist Nazl Fis Nucl, I-00185 Rome, Italy.
Univ Roma La Sapienza, I-00185 Rome, Italy.
Russian Acad Sci, Inst Nucl Phys, St Petersburg, Russia.
Univ Salerno, I-84100 Salerno, Italy.
INFN, I-84100 Salerno, Italy.
Univ Calif San Diego, La Jolla, CA 92093 USA.
Univ Santiago, Dept Fis Particulas Elementales, E-15706 Santiago De Compostela, Spain.
Bulgarian Acad Sci, Cent Lab Mechatron & Instrumentat, BU-1113 Sofia, Bulgaria.
Korea Adv Inst Sci & Technol, Ctr High Energy Phys, Taejon 305701, South Korea.
Univ Alabama, University, AL 35486 USA.
Univ Utrecht, NL-3584 CB Utrecht, Netherlands.
NIKHEF, NL-3584 CB Utrecht, Netherlands.
Purdue Univ, W Lafayette, IN 47907 USA.
Paul Scherrer Inst, CH-5232 Villigen, Switzerland.
DESY, Inst Hochenergiephys, D-15738 Zeuthen, Germany.
Swiss Fed Inst Technol, CH-8093 Zurich, Switzerland.
Univ Hamburg, D-22761 Hamburg, Germany.
High Energy Phys Grp, Taipei, Taiwan.
RP Acciarri, M (reprint author), Ist Nazl Fis Nucl, Via Celoria 16, I-20133 Milan, Italy.
RI Fiandrini, Emanuele/C-4549-2008; Berdugo, Javier/A-2858-2015;
D'Alessandro, Raffaello/F-5897-2015; Lista, Luca/C-5719-2008; Kirkby,
Jasper/A-4973-2012; Servoli, Leonello/E-6766-2012; bertucci,
bruna/J-5237-2012; Cavallo, Nicola/F-8913-2012; Cerrada,
Marcos/J-6934-2014; de la Cruz, Begona/K-7552-2014; Josa,
Isabel/K-5184-2014; Vogel, Helmut/N-8882-2014; Ferguson,
Thomas/O-3444-2014; Sanchez, Eusebio/H-5228-2015; Duran,
Ignacio/H-7254-2015; Rancoita, Pier Giorgio/J-9896-2015; Hoorani,
Hafeez/D-1791-2013; Palomares, Carmen/H-7783-2015; Fedin,
Oleg/H-6753-2016; Roth, Stefan/J-2757-2016; Kamyshkov, Yuri/J-7999-2016;
Di Lodovico, Francesca/L-9109-2016;
OI Berdugo, Javier/0000-0002-7911-8532; D'Alessandro,
Raffaello/0000-0001-7997-0306; Kirkby, Jasper/0000-0003-2341-9069;
Servoli, Leonello/0000-0003-1725-9185; Cerrada,
Marcos/0000-0003-0112-1691; Vogel, Helmut/0000-0002-6109-3023; Ferguson,
Thomas/0000-0001-5822-3731; Sanchez, Eusebio/0000-0002-9646-8198;
Rancoita, Pier Giorgio/0000-0002-1990-4283; Palomares,
Carmen/0000-0003-4374-9065; Roth, Stefan/0000-0003-3616-2223; Kamyshkov,
Yuri/0000-0002-3789-7152; Di Lodovico, Francesca/0000-0003-3952-2175;
Longo, Egidio/0000-0001-6238-6787; Ambrosi,
Giovanni/0000-0001-6977-9559; Castellini, Guido/0000-0002-0177-0643;
Read, Kenneth/0000-0002-3358-7667; Diemoz, Marcella/0000-0002-3810-8530;
Doria, Alessandra/0000-0002-5381-2649; Sciacca,
Crisostomo/0000-0002-8412-4072; Faccini, Riccardo/0000-0003-2613-5141;
Bertucci, Bruna/0000-0001-7584-293X; Filthaut,
Frank/0000-0003-3338-2247; Goldstein, Joel/0000-0003-1591-6014
NR 42
TC 9
Z9 9
U1 0
U2 4
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0370-2693
EI 1873-2445
J9 PHYS LETT B
JI Phys. Lett. B
PD JUN 18
PY 1998
VL 429
IS 3-4
BP 375
EP 386
DI 10.1016/S0370-2693(98)00438-9
PG 12
WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields
SC Astronomy & Astrophysics; Physics
GA ZZ088
UT WOS:000074694500023
ER
PT J
AU Acciarri, M
Adriani, O
Aguilar-Benitez, M
Ahlen, S
Alcaraz, J
Alemanni, G
Allaby, J
Aloisio, A
Alviggi, MG
Ambrosi, G
Anderhub, H
Andreev, VP
Angelescu, T
Anselmo, F
Arefiev, A
Azemoon, T
Aziz, T
Bagnaia, P
Baksay, L
Ball, RC
Banerjee, S
Banerjee, S
Banicz, K
Barczyk, A
Barillere, R
Barone, L
Bartalini, P
Baschirotto, A
Basile, M
Battiston, R
Bay, A
Becattini, F
Becker, U
Behner, F
Berdugo, J
Berges, P
Bertucci, B
Betev, BL
Bhattacharya, S
Biasini, M
Biland, A
Bilei, GM
Blaising, JJ
Blyth, SC
Bobbink, GJ
Bock, R
Bohm, A
Boldizsar, L
Borgia, B
Bourilkov, D
Bourquin, M
Boutigny, D
Braccini, S
Branson, JG
Brigljevic, V
Brock, IC
Buffini, A
Buijs, A
Burger, JD
Burger, WJ
Busenitz, J
Cai, XD
Campanelli, M
Capell, M
Romeo, GC
Carlino, G
Cartacci, AM
Casaus, J
Castellini, G
Cavallari, F
Cavallo, N
Cecchi, C
Cerrada, M
Cesaroni, F
Chamizo, M
Chang, YH
Chaturvedi, UK
Chekanov, SV
Chemarin, M
Chen, A
Chen, G
Chen, GC
Chen, HF
Chen, HS
Chen, M
Chiefari, G
Chien, CY
Cifarelli, L
Cindolo, F
Civinini, C
Clare, I
Clare, R
Cohn, HO
Coignet, G
Colijn, AP
Colino, N
Costantini, S
Cotorobai, F
de la Cruz, B
Csilling, A
Dai, TS
D'Alessandro, R
de Asmundis, R
Degre, A
Deiters, K
Denes, P
DeNotaristefani, F
DiBitonto, D
Diemoz, M
van Dierendonck, D
Di Lodovico, F
Dionisi, C
Dittmar, M
Dominguez, A
Doria, A
Dova, MT
Drago, E
Duchesneau, D
Duinker, P
Duran, I
Dutta, S
Easo, S
Efremenko, Y
El Mamouni, H
Engler, A
Eppling, FJ
Erne, FC
Ernenwein, JP
Extermann, P
Fabre, M
Faccini, R
Falciano, S
Favara, A
Fay, J
Fedin, O
Felcini, M
Fenyi, B
Ferguson, T
Ferroni, F
Fesefeldt, H
Fiandrini, E
Field, JH
Filthaut, F
Fisher, PH
Fisk, I
Forconi, G
Fredj, L
Freudenreich, K
Furetta, C
Galaktionov, Y
Ganguli, SN
Garcia-Abia, P
Gau, SS
Gentile, S
Gerald, J
Gheordanescu, N
Giagu, S
Goldfarb, S
Goldstein, J
Gong, ZF
Gougas, A
Gratta, G
Gruenewald, MW
Gupta, VK
Gurtu, A
Gutay, LJ
Haas, D
Hartmann, B
Hasan, A
Hatzifotiadou, D
Hebbeker, T
Herve, A
Hirschfelder, J
van Hoek, WC
Hofer, H
Hoorani, H
Hou, SR
Hu, G
Innocente, V
Jenkes, K
Jin, BN
Jones, LW
de Jong, P
Josa-Mutuberria, I
Kasser, A
Khan, RA
Kamrad, D
Kamyshkov, Y
Kapustinsky, JS
Karyotakis, Y
Kaur, M
Kienzle-Focacci, MN
Kim, D
Kim, DH
Kim, JK
Kim, SC
Kinnison, WW
Kirkby, A
Kirkby, D
Kirkby, J
Kiss, D
Kittel, W
Klimentov, A
Konig, AC
Kopp, A
Korolko, I
Koutsenko, V
Kraemer, RW
Krenz, W
Kunin, A
Lacentre, P
de Guevara, PL
Landi, G
Lapoint, C
Lassila-Perini, K
Laurikainen, P
Lavorato, A
Lebeau, M
Lebedev, A
Lebrun, P
Lecomte, P
Lecoq, P
Le Coultre, P
Lee, HJ
Leggett, C
Le Goff, JM
Leiste, R
Leonardi, E
Levtchenko, P
Li, C
Lin, CH
Lin, WT
Linde, FL
Lista, L
Liu, ZA
Lohmann, W
Longo, E
Lu, W
Lu, YS
Lubelsmeyer, K
Luci, C
Luckey, D
Luminari, L
Lustermann, W
Ma, WG
Maity, M
Majumder, G
Malgeri, L
Malinin, A
Mana, C
Mangeol, D
Mangla, S
Marchesini, P
Marin, A
Martin, JP
Marzano, F
Massaro, GGG
McNally, D
Mele, S
Merola, L
Meschini, M
Metzger, WJ
von der Mey, M
Mi, Y
Migani, D
Mihul, A
van Mil, AJW
Milcent, H
Mirabelli, G
Mnich, J
Molnar, P
Monteleoni, B
Moore, R
Moulik, T
Mount, R
Muheim, F
Muijs, AJM
Nahn, S
Napolitano, M
Nessi-Tedaldi, F
Newman, H
Niessen, T
Nippe, A
Nisati, A
Nowak, H
Oh, YD
Opitz, H
Organtini, G
Ostonen, R
Palit, S
Palomares, C
Pandoulas, D
Paoletti, S
Paolucci, P
Park, HK
Park, IH
Pascale, G
Passaleva, G
Patricelli, S
Paul, T
Pauluzzi, M
Paus, C
Pauss, F
Peach, D
Pei, YJ
Pensotti, S
Perret-Gallix, D
Petersen, B
Petrak, S
Pevsner, A
Piccolo, D
Pieri, M
Piroue, PA
Pistolesi, E
Plyaskin, V
Pohl, M
Pojidaev, V
Postema, H
Produit, N
Prokofiev, D
Quartieri, J
Rahal-Callot, G
Raja, N
Rancoita, PG
Rattaggi, M
Raven, G
Razis, P
Read, K
Ren, D
Rescigno, M
Reucroft, S
van Rhee, T
Riemann, S
Riles, K
Rind, O
Robohm, A
Rodin, J
Roe, BP
Romero, L
Rosier-Lees, S
Rosselet, P
van Rossum, W
Roth, S
Rubio, JA
Ruschmeier, D
Rykaczewski, H
Salicio, J
Sanchez, E
Sanders, MP
Sarakinos, ME
Sarkar, S
Sauvage, G
Schafer, C
Schegelsky, V
Schmidt-Kaerst, S
Schmitz, D
Schneegans, M
Scholz, N
Schopper, H
Schotanus, DJ
Schwenke, J
Schwering, G
Sciacca, C
Sciarrino, D
Servoli, L
Shevchenko, S
Shivarov, N
Shoutko, V
Shukla, J
Shumilov, E
Shvorob, A
Siedenburg, T
Son, D
Soulimov, V
Smith, B
Spillantini, P
Steuer, M
Stickland, DP
Stone, H
Stoyanov, B
Straessner, A
Sudhakar, K
Sultanov, G
Sun, LZ
Susinno, GF
Suter, H
Swain, JS
Tang, SW
Tauscher, L
Taylor, L
Ting, SCC
Ting, SM
Tonwar, SC
Toth, J
Tully, C
Tuchscherer, H
Tung, KL
Uchida, Y
Ulbricht, J
Uwer, U
Valente, E
Vesztergombi, G
Vetlitsky, I
Viertel, G
Vivargent, M
Vlachos, S
Volkert, R
Vogel, H
Vogt, H
Vorobiev, I
Vorobyov, AA
Vorvolakos, A
Wadhwa, M
Wallraff, W
Wang, JC
Wang, XL
Wang, ZM
Weber, A
Wu, SX
Wynhoff, S
Xu, J
Xu, ZZ
Yang, BZ
Yang, CG
Yao, XY
Ye, JB
Yeh, SC
You, JM
Zalite, A
Zalite, Y
Zemp, P
Zeng, Y
Zhang, Z
Zhang, ZP
Zhou, B
Zhou, Y
Zhu, GY
Zhu, RY
Zichichi, Z
Ziegler, F
AF Acciarri, M
Adriani, O
Aguilar-Benitez, M
Ahlen, S
Alcaraz, J
Alemanni, G
Allaby, J
Aloisio, A
Alviggi, MG
Ambrosi, G
Anderhub, H
Andreev, VP
Angelescu, T
Anselmo, F
Arefiev, A
Azemoon, T
Aziz, T
Bagnaia, P
Baksay, L
Ball, RC
Banerjee, S
Banerjee, S
Banicz, K
Barczyk, A
Barillere, R
Barone, L
Bartalini, P
Baschirotto, A
Basile, M
Battiston, R
Bay, A
Becattini, F
Becker, U
Behner, F
Berdugo, J
Berges, P
Bertucci, B
Betev, BL
Bhattacharya, S
Biasini, M
Biland, A
Bilei, GM
Blaising, JJ
Blyth, SC
Bobbink, GJ
Bock, R
Bohm, A
Boldizsar, L
Borgia, B
Bourilkov, D
Bourquin, M
Boutigny, D
Braccini, S
Branson, JG
Brigljevic, V
Brock, IC
Buffini, A
Buijs, A
Burger, JD
Burger, WJ
Busenitz, J
Cai, XD
Campanelli, M
Capell, M
Romeo, GC
Carlino, G
Cartacci, AM
Casaus, J
Castellini, G
Cavallari, F
Cavallo, N
Cecchi, C
Cerrada, M
Cesaroni, F
Chamizo, M
Chang, YH
Chaturvedi, UK
Chekanov, SV
Chemarin, M
Chen, A
Chen, G
Chen, GC
Chen, HF
Chen, HS
Chen, M
Chiefari, G
Chien, CY
Cifarelli, L
Cindolo, F
Civinini, C
Clare, I
Clare, R
Cohn, HO
Coignet, G
Colijn, AP
Colino, N
Costantini, S
Cotorobai, F
de la Cruz, B
Csilling, A
Dai, TS
D'Alessandro, R
de Asmundis, R
Degre, A
Deiters, K
Denes, P
DeNotaristefani, F
DiBitonto, D
Diemoz, M
van Dierendonck, D
Di Lodovico, F
Dionisi, C
Dittmar, M
Dominguez, A
Doria, A
Dova, MT
Drago, E
Duchesneau, D
Duinker, P
Duran, I
Dutta, S
Easo, S
Efremenko, Y
El Mamouni, H
Engler, A
Eppling, FJ
Erne, FC
Ernenwein, JP
Extermann, P
Fabre, M
Faccini, R
Falciano, S
Favara, A
Fay, J
Fedin, O
Felcini, M
Fenyi, B
Ferguson, T
Ferroni, F
Fesefeldt, H
Fiandrini, E
Field, JH
Filthaut, F
Fisher, PH
Fisk, I
Forconi, G
Fredj, L
Freudenreich, K
Furetta, C
Galaktionov, Y
Ganguli, SN
Garcia-Abia, P
Gau, SS
Gentile, S
Gerald, J
Gheordanescu, N
Giagu, S
Goldfarb, S
Goldstein, J
Gong, ZF
Gougas, A
Gratta, G
Gruenewald, MW
Gupta, VK
Gurtu, A
Gutay, LJ
Haas, D
Hartmann, B
Hasan, A
Hatzifotiadou, D
Hebbeker, T
Herve, A
Hirschfelder, J
van Hoek, WC
Hofer, H
Hoorani, H
Hou, SR
Hu, G
Innocente, V
Jenkes, K
Jin, BN
Jones, LW
de Jong, P
Josa-Mutuberria, I
Kasser, A
Khan, RA
Kamrad, D
Kamyshkov, Y
Kapustinsky, JS
Karyotakis, Y
Kaur, M
Kienzle-Focacci, MN
Kim, D
Kim, DH
Kim, JK
Kim, SC
Kinnison, WW
Kirkby, A
Kirkby, D
Kirkby, J
Kiss, D
Kittel, W
Klimentov, A
Konig, AC
Kopp, A
Korolko, I
Koutsenko, V
Kraemer, RW
Krenz, W
Kunin, A
Lacentre, P
de Guevara, PL
Landi, G
Lapoint, C
Lassila-Perini, K
Laurikainen, P
Lavorato, A
Lebeau, M
Lebedev, A
Lebrun, P
Lecomte, P
Lecoq, P
Le Coultre, P
Lee, HJ
Leggett, C
Le Goff, JM
Leiste, R
Leonardi, E
Levtchenko, P
Li, C
Lin, CH
Lin, WT
Linde, FL
Lista, L
Liu, ZA
Lohmann, W
Longo, E
Lu, W
Lu, YS
Lubelsmeyer, K
Luci, C
Luckey, D
Luminari, L
Lustermann, W
Ma, WG
Maity, M
Majumder, G
Malgeri, L
Malinin, A
Mana, C
Mangeol, D
Mangla, S
Marchesini, P
Marin, A
Martin, JP
Marzano, F
Massaro, GGG
McNally, D
Mele, S
Merola, L
Meschini, M
Metzger, WJ
von der Mey, M
Mi, Y
Migani, D
Mihul, A
van Mil, AJW
Milcent, H
Mirabelli, G
Mnich, J
Molnar, P
Monteleoni, B
Moore, R
Moulik, T
Mount, R
Muheim, F
Muijs, AJM
Nahn, S
Napolitano, M
Nessi-Tedaldi, F
Newman, H
Niessen, T
Nippe, A
Nisati, A
Nowak, H
Oh, YD
Opitz, H
Organtini, G
Ostonen, R
Palit, S
Palomares, C
Pandoulas, D
Paoletti, S
Paolucci, P
Park, HK
Park, IH
Pascale, G
Passaleva, G
Patricelli, S
Paul, T
Pauluzzi, M
Paus, C
Pauss, F
Peach, D
Pei, YJ
Pensotti, S
Perret-Gallix, D
Petersen, B
Petrak, S
Pevsner, A
Piccolo, D
Pieri, M
Piroue, PA
Pistolesi, E
Plyaskin, V
Pohl, M
Pojidaev, V
Postema, H
Produit, N
Prokofiev, D
Quartieri, J
Rahal-Callot, G
Raja, N
Rancoita, PG
Rattaggi, M
Raven, G
Razis, P
Read, K
Ren, D
Rescigno, M
Reucroft, S
van Rhee, T
Riemann, S
Riles, K
Rind, O
Robohm, A
Rodin, J
Roe, BP
Romero, L
Rosier-Lees, S
Rosselet, P
van Rossum, W
Roth, S
Rubio, JA
Ruschmeier, D
Rykaczewski, H
Salicio, J
Sanchez, E
Sanders, MP
Sarakinos, ME
Sarkar, S
Sauvage, G
Schafer, C
Schegelsky, V
Schmidt-Kaerst, S
Schmitz, D
Schneegans, M
Scholz, N
Schopper, H
Schotanus, DJ
Schwenke, J
Schwering, G
Sciacca, C
Sciarrino, D
Servoli, L
Shevchenko, S
Shivarov, N
Shoutko, V
Shukla, J
Shumilov, E
Shvorob, A
Siedenburg, T
Son, D
Soulimov, V
Smith, B
Spillantini, P
Steuer, M
Stickland, DP
Stone, H
Stoyanov, B
Straessner, A
Sudhakar, K
Sultanov, G
Sun, LZ
Susinno, GF
Suter, H
Swain, JS
Tang, SW
Tauscher, L
Taylor, L
Ting, SCC
Ting, SM
Tonwar, SC
Toth, J
Tully, C
Tuchscherer, H
Tung, KL
Uchida, Y
Ulbricht, J
Uwer, U
Valente, E
Vesztergombi, G
Vetlitsky, I
Viertel, G
Vivargent, M
Vlachos, S
Volkert, R
Vogel, H
Vogt, H
Vorobiev, I
Vorobyov, AA
Vorvolakos, A
Wadhwa, M
Wallraff, W
Wang, JC
Wang, XL
Wang, ZM
Weber, A
Wu, SX
Wynhoff, S
Xu, J
Xu, ZZ
Yang, BZ
Yang, CG
Yao, XY
Ye, JB
Yeh, SC
You, JM
Zalite, A
Zalite, Y
Zemp, P
Zeng, Y
Zhang, Z
Zhang, ZP
Zhou, B
Zhou, Y
Zhu, GY
Zhu, RY
Zichichi, Z
Ziegler, F
TI Measurement of tau polarisation at LEP
SO PHYSICS LETTERS B
LA English
DT Article
ID LUND MONTE-CARLO; RADIATIVE-CORRECTIONS; DECAY CORRELATIONS; MICHEL
PARAMETERS; NEUTRINO HELICITY; JET FRAGMENTATION; E+E ANNIHILATION; PAIR
PRODUCTION; POLARIZATION; CONSTRUCTION
AB Using the data collected with the L3 detector at LEP between 1990 and 1995, corresponding to an integrated luminosity of 149 pb(-1), the tau longitudinal polarisation has been measured as a function of the production polar angle using the tau decays tau(-) --> h(-)nu(tau) (h = pi,rho,a(1)) and tau(-)-->l(-)<(nu)over bar>(l)nu(tau) (l = e,mu). From this measurement the quantities A(c) and A(tau), which depend on the couplings of the electron and the tau to the Z, are determined to be A(c) = 0.1678 +/- 0.0127 +/- 0.0030 and A(tau) = 0.1476 +/- 0.0088 +/- 0.0062, consistent with the hypothesis of e-tau universality, Under this assumption a value of A(l) = 0.1540 +/- 0.0074 +/- 0.0044 is obtained, yielding the value of the effective weak mixing angle sin(2)<(theta)over bar>(W) = 0.2306 +/- 0.0011. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Ist Nazl Fis Nucl, I-20133 Milan, Italy.
Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany.
Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany.
NIKHEF, Natl Inst High Energy Phys, NL-1009 DB Amsterdam, Netherlands.
Univ Amsterdam, NL-1009 DB Amsterdam, Netherlands.
Univ Michigan, Ann Arbor, MI 48109 USA.
Lab Annecy Le Vieux Phys Particules, CNRS, IN2P3, F-74941 Annecy Le Vieux, France.
Johns Hopkins Univ, Baltimore, MD 21218 USA.
Univ Basel, Inst Phys, CH-4056 Basel, Switzerland.
Inst High Energy Phys, Beijing 100039, Peoples R China.
Humboldt Univ, D-10099 Berlin, Germany.
Univ Bologna, I-40126 Bologna, Italy.
Ist Nazl Fis Nucl, I-40126 Bologna, Italy.
Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India.
Boston Univ, Boston, MA 02215 USA.
Northeastern Univ, Boston, MA 02115 USA.
Inst Atom Phys, R-76900 Bucharest, Romania.
Univ Bucharest, R-76900 Bucharest, Romania.
Hungarian Acad Sci, Cent Res Inst Phys, H-1525 Budapest 114, Hungary.
MIT, Cambridge, MA 02139 USA.
Ist Nazl Fis Nucl, I-50125 Florence, Italy.
Univ Florence, I-50125 Florence, Italy.
CERN, European Lab Particle Phys, CH-1211 Geneva 23, Switzerland.
FBLJA Project, World Lab, CH-1211 Geneva 23, Switzerland.
Univ Geneva, CH-1211 Geneva 4, Switzerland.
Univ Sci & Technol China, Hefei 230029, Anhui, Peoples R China.
Res Inst High Energy Phys, SEFT, SF-00014 Helsinki, Finland.
Univ Lausanne, CH-1015 Lausanne, Switzerland.
Ist Nazl Fis Nucl, I-73100 Lecce, Italy.
Univ Lecce, I-73100 Lecce, Italy.
Los Alamos Natl Lab, Los Alamos, NM 87544 USA.
Univ Lyon 1, CNRS, IN2P3, Inst Phys Nucl Lyon, F-69622 Villeurbanne, France.
CIEMAT, E-28040 Madrid, Spain.
Inst Theoret & Expt Phys, Moscow 117259, Russia.
Ist Nazl Fis Nucl, I-80125 Naples, Italy.
Univ Naples Federico II, I-80125 Naples, Italy.
Univ Cyprus, Dept Nat Sci, Nicosia, Cyprus.
Catholic Univ Nijmegen, NL-6525 ED Nijmegen, Netherlands.
Natl Inst Nucl Phys & High Energy Phys, NL-6525 ED Nijmegen, Netherlands.
Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
CALTECH, Pasadena, CA 91125 USA.
Ist Nazl Fis Nucl, I-06100 Perugia, Italy.
Univ Perugia, I-06100 Perugia, Italy.
Carnegie Mellon Univ, Pittsburgh, PA 15213 USA.
Princeton Univ, Princeton, NJ 08544 USA.
Ist Nazl Fis Nucl, I-00185 Rome, Italy.
Univ Roma La Sapienza, I-00185 Rome, Italy.
Russian Acad Sci, Inst Nucl Phys, St Petersburg, Russia.
Univ Salerno, I-84100 Salerno, Italy.
INFN, I-84100 Salerno, Italy.
Univ Calif San Diego, San Diego, CA 92093 USA.
Univ Santiago, Dept Fis Particulas Elementales, E-15706 Santiago De Compostela, Spain.
Bulgarian Acad Sci, Cent Lab Mechatron & Instrumentat, BU-1113 Sofia, Bulgaria.
Korea Adv Inst Sci & Technol, Ctr High Energy Phys, Taejon 305701, South Korea.
Univ Alabama, Tuscaloosa, AL 35486 USA.
Univ Utrecht, NL-3584 CB Utrecht, Netherlands.
NIKHEF, NL-3584 CB Utrecht, Netherlands.
Purdue Univ, W Lafayette, IN 47907 USA.
Paul Scherrer Inst, CH-5232 Villigen, Switzerland.
DESY, Inst Hochenergiephys, D-15738 Zeuthen, Germany.
Swiss Fed Inst Technol, CH-8093 Zurich, Switzerland.
Univ Hamburg, D-22761 Hamburg, Germany.
Natl Cent Univ, Chungli, Taiwan.
Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan.
RP Acciarri, M (reprint author), Ist Nazl Fis Nucl, Via Celoria 16, I-20133 Milan, Italy.
RI Fiandrini, Emanuele/C-4549-2008; Lista, Luca/C-5719-2008; Josa,
Isabel/K-5184-2014; Vogel, Helmut/N-8882-2014; Ferguson,
Thomas/O-3444-2014; Berdugo, Javier/A-2858-2015; Kirkby,
Jasper/A-4973-2012; Servoli, Leonello/E-6766-2012; bertucci,
bruna/J-5237-2012; Cavallo, Nicola/F-8913-2012; Cerrada,
Marcos/J-6934-2014; de la Cruz, Begona/K-7552-2014; D'Alessandro,
Raffaello/F-5897-2015; Sanchez, Eusebio/H-5228-2015; Duran,
Ignacio/H-7254-2015; Rancoita, Pier Giorgio/J-9896-2015; Hoorani,
Hafeez/D-1791-2013; Palomares, Carmen/H-7783-2015; Fedin,
Oleg/H-6753-2016; Roth, Stefan/J-2757-2016; Kamyshkov, Yuri/J-7999-2016;
Di Lodovico, Francesca/L-9109-2016;
OI Vogel, Helmut/0000-0002-6109-3023; Ferguson, Thomas/0000-0001-5822-3731;
Berdugo, Javier/0000-0002-7911-8532; Kirkby, Jasper/0000-0003-2341-9069;
Servoli, Leonello/0000-0003-1725-9185; Cerrada,
Marcos/0000-0003-0112-1691; D'Alessandro, Raffaello/0000-0001-7997-0306;
Sanchez, Eusebio/0000-0002-9646-8198; Rancoita, Pier
Giorgio/0000-0002-1990-4283; Palomares, Carmen/0000-0003-4374-9065;
Roth, Stefan/0000-0003-3616-2223; Kamyshkov, Yuri/0000-0002-3789-7152;
Di Lodovico, Francesca/0000-0003-3952-2175; Produit,
Nicolas/0000-0001-7138-7677
NR 40
TC 24
Z9 24
U1 0
U2 4
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0370-2693
EI 1873-2445
J9 PHYS LETT B
JI Phys. Lett. B
PD JUN 18
PY 1998
VL 429
IS 3-4
BP 387
EP 398
DI 10.1016/S0370-2693(98)00406-7
PG 12
WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields
SC Astronomy & Astrophysics; Physics
GA ZZ088
UT WOS:000074694500024
ER
PT J
AU Wang, J
Houk, RS
Dreessen, D
Wiederin, DR
AF Wang, J
Houk, RS
Dreessen, D
Wiederin, DR
TI Identification of inorganic elements in proteins in human serum and in
DNA fragments by size exclusion chromatography and inductively coupled
plasma mass spectrometry with a magnetic sector mass spectrometer
SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
LA English
DT Article
ID PHOSPHATE DIESTERS; HUMAN ERYTHROCYTES; CANCER PREVENTION; HYDROLYSIS;
BINDING; DAMAGE; RESOLUTION; REACTIVITY; COMPLEXES; SELENIUM
AB A general method to identify trace elements in biological molecules is described. These measurements are made in only a few minutes without preliminary isolation and preconcentration steps; Many unusual or difficult elements, such as Cr, Se, Cd, Th, and U, can be observed at ambient levels bound to proteins in human serum. A new protein or family of proteins, that either contain Se or that bind Se molecules, is found with molecular weight similar to 760 kDa. Binding of metal cations to DNA restriction fragments can be studied by similar procedures both for essential elements such as Mn and Fe and toxic ones such as Cd and Pb. In particular, trace Pb, Cd, and Co are completely bound to DNA fragments. Reduction of chromate to a cation (probably Cr3+) and subsequent binding of the Cr cation to DNA is also demonstrated.
C1 Iowa State Univ, US DOE, Ames Lab, Dept Chem, Ames, IA 50011 USA.
Transgenom CETAC Technol Inc, Omaha, NE 68107 USA.
RP Houk, RS (reprint author), Iowa State Univ, US DOE, Ames Lab, Dept Chem, Ames, IA 50011 USA.
EM rshouk@iastate.edu
NR 31
TC 35
Z9 35
U1 1
U2 2
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 JUN 17
PY 1998
VL 120
IS 23
BP 5793
EP 5799
DI 10.1021/ja9735970
PG 7
WC Chemistry, Multidisciplinary
SC Chemistry
GA ZV408
UT WOS:000074301600022
ER
PT J
AU Linehan, JC
Yonker, CR
Bays, JT
Autrey, ST
Bitterwolf, TE
Gallagher, S
AF Linehan, JC
Yonker, CR
Bays, JT
Autrey, ST
Bitterwolf, TE
Gallagher, S
TI A kinetic study of the thermal loss of ethylene from
CpNb(CO)(3)(eta(2)-C2H4) in supercritical fluid solvents
SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
LA English
DT Article
ID CARBON-DIOXIDE; HOMOGENEOUS CATALYSIS; FORMIC-ACID; HYDROGENATION;
CR(CO)(5)(C2H4); SUBSTITUTION; N2
C1 Pacific NW Natl Lab, Dept Chem Sci, Richland, WA 99352 USA.
Univ Idaho, Dept Chem, Moscow, ID 83844 USA.
RP Linehan, JC (reprint author), Pacific NW Natl Lab, Dept Chem Sci, POB 999, Richland, WA 99352 USA.
NR 19
TC 8
Z9 8
U1 0
U2 3
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 JUN 17
PY 1998
VL 120
IS 23
BP 5826
EP 5827
DI 10.1021/ja974054t
PG 2
WC Chemistry, Multidisciplinary
SC Chemistry
GA ZV408
UT WOS:000074301600034
ER
PT J
AU George, EP
Kennedy, RL
Pope, DP
AF George, EP
Kennedy, RL
Pope, DP
TI Review of trace element effects on high-temperature fracture of Fe- and
Ni-base alloys
SO PHYSICA STATUS SOLIDI A-APPLIED RESEARCH
LA English
DT Article; Proceedings Paper
CT 4th International Conference on Ultra-High-Purity Metallic-Base
Materials (UHPM-97)
CY SEP 11-13, 1997
CL PHILADELPHIA, PENNSYLVANIA
ID STRESS RELIEF CRACKING; BORON-DOPED NI3AL; MO-V STEELS; CREEP DUCTILITY;
INTERGRANULAR FRACTURE; DYNAMIC EMBRITTLEMENT; ELEVATED-TEMPERATURE;
SURFACE-DIFFUSION; NUCLEATION SITES; CR ALLOYS
AB Trace elements can have harmful or beneficial effects on elevated-temperature mechanical properties. In iron and low-alloy steels, S at high concentrations forms sulfides which are potent nucleation sites for intergranular creep cavities. As a result, ductility decreases and fracture becomes increasingly intergranular with increasing S concentration. Oxides and nitrides nucleate cavities only in the presence of segregated S; by themselves they are relatively benign. The harmful effects of S can be ameliorated by the addition of carbon and phosphorus. It is unclear whether C and P have beneficial effects of their own, or whether they act merely by counteracting the negative effects of sulfur. Carbides almost never nucleate cavities. In Ni-base alloys, too, S is deleterious, and alloying with strong sulfide getters increases ductility and rupture life. Boron and P interact synergistically and increase stress rupture lives in some alloys but not in others. The detailed mechanism of this interaction is not well understood.
C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA.
Allvac, Monroe, NC 28110 USA.
Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA.
RP George, EP (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, 1 Bethel Valley Rd, Oak Ridge, TN 37831 USA.
RI George, Easo/L-5434-2014
NR 104
TC 19
Z9 19
U1 0
U2 7
PU WILEY-V C H VERLAG GMBH
PI BERLIN
PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY
SN 0031-8965
J9 PHYS STATUS SOLIDI A
JI Phys. Status Solidi A-Appl. Res.
PD JUN 16
PY 1998
VL 167
IS 2
BP 313
EP 333
DI 10.1002/(SICI)1521-396X(199806)167:2<313::AID-PSSA313>3.0.CO;2-5
PG 21
WC Materials Science, Multidisciplinary; Physics, Applied; Physics,
Condensed Matter
SC Materials Science; Physics
GA ZY656
UT WOS:000074645900006
ER
PT J
AU Thompson, JA
Scott, BL
Sauer, NN
AF Thompson, JA
Scott, BL
Sauer, NN
TI Triethylenetetraminehexaacetic acid complex of lead
SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS
LA English
DT Article
ID SOILS
AB In the title compound, tetrasodium mu-[3,6,9,12-tetrakis( carboxymethyl)-3,6, 9,12-tetraazatetradecanedioato- 1 kappa(5)O(1),N-3, O-3,N-6,O-6: 2 kappa(5)N(9), (ON12)-N-9,(OO14)-O-12]dilead dinitrate decahydrate, Na-4[Pb-2(C18H24N4O12)](NO3)(2).-10H(2)O, the Pb2+ ions have highly distorted bonding geometry, with a primary coordination number of five and two secondary intermolecular contacts. The Pb-N bond distances range from 2.505(4) to 2.641(4) Angstrom, and the Pb-O bond distances range from 2.454(3) to 2.559 (3) Angstrom. The binuclear lead complexes sit on inversion centers and are bridged to form polymeric structures. The polymers are linked into sheets via N ... O contacts.
C1 Polylonix Separat Technol Inc, Dayton, NJ 08810 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
RP Thompson, JA (reprint author), Polylonix Separat Technol Inc, Dayton, NJ 08810 USA.
RI Scott, Brian/D-8995-2017
OI Scott, Brian/0000-0003-0468-5396
NR 15
TC 6
Z9 7
U1 0
U2 0
PU MUNKSGAARD INT PUBL LTD
PI COPENHAGEN
PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK
SN 0108-2701
J9 ACTA CRYSTALLOGR C
JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun.
PD JUN 15
PY 1998
VL 54
BP 734
EP 736
DI 10.1107/S0108270197018428
PN 6
PG 3
WC Chemistry, Multidisciplinary; Crystallography
SC Chemistry; Crystallography
GA 100PR
UT WOS:000074825000016
ER
PT J
AU Janata, J
Josowicz, M
Vanysek, P
DeVaney, DM
AF Janata, J
Josowicz, M
Vanysek, P
DeVaney, DM
TI Chemical sensors
SO ANALYTICAL CHEMISTRY
LA English
DT Review
ID ION-SELECTIVE ELECTRODES; SURFACE-PLASMON-RESONANCE; ELECTROCHEMICAL GAS
SENSORS; QUARTZ-CRYSTAL-MICROBALANCE; LANGMUIR-BLODGETT-FILMS;
ACOUSTIC-WAVE SENSOR; THICKNESS-SHEAR MODE; AMPEROMETRIC HYDROGEN
SENSOR; ARTIFICIAL NEURAL-NETWORK; SOLID-POLYMER ELECTROLYTE
C1 Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA.
No Illinois Univ, Dept Chem, De Kalb, IL 60115 USA.
Pacific NW Natl Lab, Richland, WA 99352 USA.
RP Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA.
RI Vanysek, Petr/A-1949-2016
OI Vanysek, Petr/0000-0002-5458-393X
NR 916
TC 138
Z9 139
U1 7
U2 36
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 JUN 15
PY 1998
VL 70
IS 12
BP 179R
EP 208R
PG 30
WC Chemistry, Analytical
SC Chemistry
GA ZU095
UT WOS:000074161100008
ER
PT J
AU Yan, Y
Pennycook, SJ
Xu, Z
Viehland, D
AF Yan, Y
Pennycook, SJ
Xu, Z
Viehland, D
TI Determination of the ordered structures of Pb(Mg1/3Nb2/3)O-3 and
Ba(Mg1/3Nb2/3)O-3 by atomic-resolution Z-contrast imaging
SO APPLIED PHYSICS LETTERS
LA English
DT Article
ID CERAMICS; PEROVSKITES; CRYSTALS
AB The atomic structure of ordered domains in Ba(Mg1/3Nb2/3)O-3 and La-doped and undoped Pb(Mg1/3Nb2/3)O-3 is Studied by high-resolution Z-contrast imaging. The ordered domain structure in both doped and undoped Pb(Mg1/3Nb2/3)O-3 is determined to be in agreement with the charge balanced random-layer model and inconsistent with the space-charge model. It is shown that La doping in Pb(Mg1/3Nb2/3)O-3 enhances not only the domain size but also the degree of ordering. (C) 1998 American Institute of Physics.
C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA.
Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA.
RP Yan, Y (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA.
EM yanfa@solid.ssd.ornl.gov
NR 15
TC 102
Z9 105
U1 1
U2 6
PU AMER INST PHYSICS
PI WOODBURY
PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999
USA
SN 0003-6951
J9 APPL PHYS LETT
JI Appl. Phys. Lett.
PD JUN 15
PY 1998
VL 72
IS 24
BP 3145
EP 3147
DI 10.1063/1.121574
PG 3
WC Physics, Applied
SC Physics
GA 108PG
UT WOS:000075274200017
ER
PT J
AU Wei, SH
Zhang, SB
Zunger, A
AF Wei, SH
Zhang, SB
Zunger, A
TI Effects of Ga addition to CuInSe2 on its electronic, structural, and
defect properties
SO APPLIED PHYSICS LETTERS
LA English
DT Article
AB Using a first-principles band structure method we have theoretically studied the effects of Ga additions on the electronic and structural properties of CuInSe2. We find that (i) with increasing x(Ga) the valence band maximum of CuIn1-xGaxSe2 (CIGS) decreases slightly, while the conduction band minimum (and the band gap) of CIGS increases significantly, (ii) the acceptor formation energies are similar in both CuInSe2 (CIS) and CuGaSe2 (CGS), but the donor formation energy is larger in CGS than in CIS, (iii) the acceptor transition levels are shallower in CGS than in CIS, but the Ga-Cu donor level in CGS is much deeper than the In-Cu donor level in CIS, and (iv) the stability domain of the chalcopyrite phase increases with respect to ordered defect compounds. Our results are compared with available experimental observations. (C) 1998 American Institute of Physics.
C1 Natl Renewable Energy Lab, Golden, CO 80401 USA.
RP Wei, SH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA.
EM shw@sst.nrel.gov
RI Zunger, Alex/A-6733-2013; Krausnick, Jennifer/D-6291-2013; Zhang,
Shengbai/D-4885-2013
OI Zhang, Shengbai/0000-0003-0833-5860
NR 19
TC 292
Z9 295
U1 10
U2 133
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 JUN 15
PY 1998
VL 72
IS 24
BP 3199
EP 3201
DI 10.1063/1.121548
PG 3
WC Physics, Applied
SC Physics
GA 108PG
UT WOS:000075274200035
ER
PT J
AU Basilevsky, MV
Rostov, IV
Newton, MD
AF Basilevsky, MV
Rostov, IV
Newton, MD
TI A frequency-resolved cavity model (FRCM) for treating equilibrium and
non-equilibrium solvation energies
SO CHEMICAL PHYSICS
LA English
DT Article
ID ELECTRON-TRANSFER THEORY; NONLOCAL ELECTROSTATICS; DIELECTRIC FUNCTION;
IONIC SOLVATION; DIPOLAR LIQUIDS; POLAR-SOLVENT; DYNAMICS; RELAXATION;
FLUIDS
AB A refined continuum medium model, denoted as the 'frequency-resolved cavity model' (FRCM), for describing solvation effects of electrically charged solutes in polar solvents is considered. The principal distinction between the commonly accepted Born-Kirkwood-Onsager model and the FRCM treatment is that in the latter case the medium polarization field induced by the solute charge distribution is subdivided into inertial and inertialess components associated with different cavities. The inertialess field, arising from solvent electronic polarization modes, involves an inner cavity confined inside a larger one, which establishes the boundary for inertial polarization modes corresponding to collective orientational and translational motions of solvent molecules outside both cavities. The model is formulated so as to be applicable to complicated chemical solutes, with no symmetry limitations imposed on the shape of their cavities and charge distributions. In introducing two cavities, we find that a single extra parameter in the refined model, chosen to control the distinct sizes of the cavities, is capable of providing the necessary additional flexibility to the FRCM parametrization scheme. By this means one can redistribute inertial and inertialess contributions to equilibrium solvation energies in a way which is consistent with existing experimental data for both equilibrium solvation energy solvent reorganization energy. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 LY Karpov Phys Chem Res Inst, Moscow 103064, Russia.
Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA.
RP Basilevsky, MV (reprint author), LY Karpov Phys Chem Res Inst, Ul Vorontsovo Pole 10, Moscow 103064, Russia.
EM basil@cc.nifhi.ac.ru
NR 36
TC 73
Z9 74
U1 0
U2 4
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0301-0104
J9 CHEM PHYS
JI Chem. Phys.
PD JUN 15
PY 1998
VL 232
IS 1-2
BP 189
EP 199
DI 10.1016/S0301-0104(98)00101-3
PG 11
WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical
SC Chemistry; Physics
GA ZV733
UT WOS:000074335600015
ER
PT J
AU Newton, MD
Basilevsky, MV
Rostov, IV
AF Newton, MD
Basilevsky, MV
Rostov, IV
TI A frequency-resolved cavity model (FRCM) for treating equilibrium and
non-equilibrium solvation energies - 2: Evaluation of solvent
reorganization energies
SO CHEMICAL PHYSICS
LA English
DT Article
ID ELECTRON-TRANSFER REACTIONS; DISTANCE; APPROXIMATION; PARAMETERS;
MOLECULES; ANIONS
AB The frequency-resolved cavity model (FRCM), a generalized continuum reaction field model, which allows for distinct effective solute cavities pertaining to optical top) and inertial tin) solvent response, has been implemented and applied to the evaluation of solvent reorganization energy (E-s) for a number of intramolecular electron transfer (ET) processes in polar media. Specifically, effective radii are defined for the solute atoms: r(infinity )= kappa . r(vdW )(where kappa is taken as a universal scale factor) and r(in) = r(infinity )+ delta (where delta is specific to a particular solvent). Optimal values of kappa and delta are determined through the use of solvation free energy data for small atomic and molecular ions, together with the experimental estimates of solvation reorganization energy (E-s) for intramolecular ET in the steroid-based radical ions studied by Closs, Miller and co-workers [G.L. Closs, L.T. Calcaterra, N.J. Green, K-W. Penfield, J.R. Miller, J. Phys. Chem. 90 (1986) 3673; M.D. Johnson, J.R. Miller, N.S. Green, G.L. Closs, J. Phys. Chem. 93 (1989) 1173; I.R. Miller, B.P. Paulson, R. Bal, G.L. Closs, J. Phys. Chem. 99 (1995) 6923]. With these optimal parameters, E-s is then evaluated for a number of other intramolecular ET processes, yielding results which are in generally good agreement with experimentally based estimates, and which give support for some of the assumptions employed in the analysis of the experimental data. Calculations with conventional solute atom radii (r(infinity) = r(in), with kappa = 1.2 and delta = 0) fitted to equilibrium solvation data yield E-s values exceeding the FRCM results by factors of greater than or equal to 2. (C) 1998 Elsevier Science B.V. All rights reserved.
C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA.
LY Karpov Phys Chem Res Inst, Moscow 103064, Russia.
RP Newton, MD (reprint author), Brookhaven Natl Lab, Dept Chem, POB 5000, Upton, NY 11973 USA.
EM newton@bnl.gov
NR 30
TC 73
Z9 73
U1 0
U2 2
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0301-0104
J9 CHEM PHYS
JI Chem. Phys.
PD JUN 15
PY 1998
VL 232
IS 1-2
BP 201
EP 210
DI 10.1016/S0301-0104(98)00102-5
PG 10
WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical
SC Chemistry; Physics
GA ZV733
UT WOS:000074335600016
ER
PT J
AU Cheney, MA
Shin, JY
Crowley, DE
Alvey, S
Malengreau, N
Sposito, G
AF Cheney, MA
Shin, JY
Crowley, DE
Alvey, S
Malengreau, N
Sposito, G
TI Atrazine dealkylation on a manganese oxide surface
SO COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
LA English
DT Article
DE abiotic degradation; dealkylation; atrazine; birnessite;
calorespirometry; pollutant breakdown
ID SOIL; DEGRADATION; BIRNESSITE
AB In this paper we report the first observation of abiotic N-dealkylation of the herbicide, atrazine[6-chloro-N-ethylN "-(l-methylethyl)- 1,3,5-triazine-2,4-diamine], by synthetic manganese oxide (delta-MnO(2)). The degradation reaction of the adsorbed herbicide was quantified at 30 degrees C by combined calorimetry, manometry, gas chromatography-mass spectrometry, liquid chromatography, and electron spin resonance spectroscopy. These combined methodologies gave clear evidence for the production of N-dealkylated forms of atrazine over a 48 h period of reaction on the surface of delta-MnO(2). This surface-catalyzed, non-photochemical abiotic N-dealkylation of the herbicide differs from known microbial pathways in soils by a higher rate of reaction and a different distribution of products among N-dealkylated forms. (C) 1998 Elsevier Science B.V.
C1 Rutgers State Univ, Cook Coll, Dept Environm Sci, New Brunswick, NJ 08903 USA.
Univ Calif Riverside, Dept Soil & Environm Sci, Riverside, CA 92521 USA.
Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA.
RP Cheney, MA (reprint author), Rutgers State Univ, Cook Coll, Dept Environm Sci, New Brunswick, NJ 08903 USA.
EM cheney@aesop.rutgers.edu
RI Crowley, David/C-1216-2014
OI Crowley, David/0000-0002-1805-8599
NR 28
TC 20
Z9 21
U1 3
U2 15
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0927-7757
J9 COLLOID SURFACE A
JI Colloid Surf. A-Physicochem. Eng. Asp.
PD JUN 15
PY 1998
VL 137
IS 1-3
BP 267
EP 273
DI 10.1016/S0927-7757(97)00368-3
PG 7
WC Chemistry, Physical
SC Chemistry
GA ZV051
UT WOS:000074263400026
ER
PT J
AU Waldfried, C
McAvoy, T
Welipitiya, D
Dowben, PA
Vescovo, E
AF Waldfried, C
McAvoy, T
Welipitiya, D
Dowben, PA
Vescovo, E
TI The influence of enhanced surface magnetism on finite-size scaling
SO EUROPHYSICS LETTERS
LA English
DT Article
ID CURIE-TEMPERATURE; FILMS; DEPENDENCE
AB The thickness-dependent spin-polarized electronic structure of strained ultrathin and thin films of Gd has been investigated. The surface magnetic structure dominates the magnetic ordering of the ultrathin Gd films. With decreasing thickness some bulk bands exhibit increasingly more "passive" magnetic behavior. These bulk bands resemble a paramagnet over an increasing volume of the bulk Brillouin zone with decreasing film thickness.
C1 Univ Nebraska, Dept Phys & Astron, Lincoln, NE 68588 USA.
Univ Nebraska, Ctr Mat Res & Anal, Lincoln, NE 68588 USA.
Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA.
RP Waldfried, C (reprint author), Univ Nebraska, Dept Phys & Astron, Lincoln, NE 68588 USA.
NR 24
TC 16
Z9 16
U1 0
U2 0
PU E D P SCIENCES
PI LES ULIS CEDEXA
PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS
CEDEXA, FRANCE
SN 0295-5075
J9 EUROPHYS LETT
JI Europhys. Lett.
PD JUN 15
PY 1998
VL 42
IS 6
BP 685
EP 690
DI 10.1209/epl/i1998-00306-3
PG 6
WC Physics, Multidisciplinary
SC Physics
GA ZW257
UT WOS:000074391300017
ER
PT J
AU Carlson, CW
McFadden, JP
Ergun, RE
Temerin, M
Peria, W
Mozer, FS
Klumpar, DM
Shelley, EG
Peterson, WK
Moebius, E
Elphic, R
Strangeway, R
Cattell, C
Pfaff, R
AF Carlson, CW
McFadden, JP
Ergun, RE
Temerin, M
Peria, W
Mozer, FS
Klumpar, DM
Shelley, EG
Peterson, WK
Moebius, E
Elphic, R
Strangeway, R
Cattell, C
Pfaff, R
TI FAST observations in the downward auroral current region: Energetic
upgoing electron beams, parallel potential drops, and ion heating
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID BIRKELAND CURRENTS; SHOCKS; MAGNETOSPHERE; FIELDS
AB Observations of plasma particles and fields by the FAST satellite find evidence of acceleration of intense upgoing electron beams by quasi-static parallel electric fields. The beam characteristics include a broad energy spectrum with peak energies between 100 eV and 5 keV, perpendicular temperatures less than 1 eV, and fluxes greater than 10(9)/cm(2)sec. Diverging electrostatic shocks associated with the beams have integrated potentials that match the beam energy. These beams are found in regions of downward Birkeland current and account for the total field-aligned current when they are present. The most energetic ion conics in the auroral zone are found coincident with these beams, in agreement with the model for "trapped" conics. The measured particle densities of the electron beams and associated ion conics are approximately equal and typically range from 1 to 10 cm(-3), with no evidence for additional cold density. The beams are seen frequently at altitudes between 2000 and 4000 km in the winter auroral zone. Their probability of occurrence has a strong dependence on season and altitude and is similar to that for upgoing ion beams in the adjacent upward current regions. This similarity suggests that the density and scale height of ionospheric ions play an important role in the formation of both types of beams.
C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Lockheed Palo Alto Res Labs, Palo Alto, CA 94304 USA.
Univ New Hampshire, Durham, NH 03824 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
Univ Calif Los Angeles, IGPP, Los Angeles, CA 90095 USA.
Univ Minnesota, Tate Lab Phys, Minneapolis, MN 55455 USA.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Carlson, CW (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
RI Pfaff, Robert/F-5703-2012; Peterson, WK/A-8706-2009;
OI Pfaff, Robert/0000-0002-4881-9715; Peterson, WK/0000-0002-1513-6096;
Moebius, Eberhard/0000-0002-2745-6978; Cattell,
Cynthia/0000-0002-3805-320X
NR 19
TC 221
Z9 220
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 JUN 15
PY 1998
VL 25
IS 12
BP 2017
EP 2020
DI 10.1029/98GL00851
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800002
ER
PT J
AU McFadden, JP
Carlson, CW
Ergun, RE
Mozer, FS
Temerin, M
Peria, W
Klumpar, DM
Shelley, EG
Peterson, WK
Moebius, E
Kistler, L
Elphic, R
Strangeway, R
Cattell, C
Pfaff, R
AF McFadden, JP
Carlson, CW
Ergun, RE
Mozer, FS
Temerin, M
Peria, W
Klumpar, DM
Shelley, EG
Peterson, WK
Moebius, E
Kistler, L
Elphic, R
Strangeway, R
Cattell, C
Pfaff, R
TI Spatial structure and gradients of ion beams observed by FAST
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID ELECTROSTATIC SHOCKS; DISTRIBUTIONS; ALTITUDE; ACCELERATION
AB High time resolution measurements of ion distributions by the FAST satellite have revealed kilometer scale spatial structure in the low altitude auroral acceleration region. The low altitude edge of the acceleration region appears to contain fingers of potential that extend hundreds of kilometers along B but are only a few to tens of kilometers wide. These fingers of potential do not appear to be strongly correlated with the local current or total potential drop. Gradients in the ion beam energy are found to be consistent with the electric field signatures expected in the quasi-static potential drop model of auroral acceleration. Typical ion beams show gradients of 0.5-1.0 keV/km, with some events as large a 3 keV/km. Integrations of the electric field along the spacecraft velocity are used to calculate parallel potential below FAST and are found to agree well with the ion beam energy for most events. One event is shown where an apparent temporal change in the auroral configuration occurs at the edge of the ion beam producing a disagreement between the beam energy and inferred potential.
C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Lockheed Palo Alto Res Labs, Palo Alto, CA 94304 USA.
Univ New Hampshire, Durham, NH 03824 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
Univ Calif Los Angeles, Los Angeles, CA 90095 USA.
Univ Minnesota, Minneapolis, MN 55455 USA.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP McFadden, JP (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
RI Pfaff, Robert/F-5703-2012; Peterson, WK/A-8706-2009;
OI Pfaff, Robert/0000-0002-4881-9715; Peterson, WK/0000-0002-1513-6096;
Moebius, Eberhard/0000-0002-2745-6978; Cattell,
Cynthia/0000-0002-3805-320X
NR 13
TC 63
Z9 63
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 JUN 15
PY 1998
VL 25
IS 12
BP 2021
EP 2024
DI 10.1029/98GL00648
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800003
ER
PT J
AU Ergun, RE
Carlson, CW
McFadden, JP
Mozer, FS
Delory, GT
Peria, W
Chaston, CC
Temerin, M
Elphic, R
Strangeway, R
Pfaff, R
Cattell, CA
Klumpar, D
Shelley, E
Peterson, W
Moebius, E
Kistler, L
AF Ergun, RE
Carlson, CW
McFadden, JP
Mozer, FS
Delory, GT
Peria, W
Chaston, CC
Temerin, M
Elphic, R
Strangeway, R
Pfaff, R
Cattell, CA
Klumpar, D
Shelley, E
Peterson, W
Moebius, E
Kistler, L
TI FAST satellite observations of electric field structures in the auroral
zone
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID PAIRED ELECTROSTATIC SHOCKS; DOUBLE-LAYERS; ALTITUDE; PARTICLE;
DISTRIBUTIONS; MAGNETOSPHERE; ACCELERATION; ION
AB Electric field and energetic particle observations by the Fast Auroral Snapshot (FAST) satellite provide convincing evidence of particle acceleration by quasi-static, magnetic-field-aligned (parallel) electric fields in both the upward and downward current regions of the auroral zone. We demonstrate this by comparing the inferred parallel potentials of electrostatic shocks with particle energies. We also report nonlinear electric field structures which may play a role in supporting parallel electric fields. These structures include large-amplitude ion cyclotron waves in the upward current region, and intense, spiky electric fields in the downward current region. The observed structures had substantial parallel components and correlative electron flux modulations. Observations of parallel electric fields in two distinct plasmas suggest that parallel electric fields may be a fundamental particle acceleration mechanism in astrophysical plasmas.
C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
Univ Calif Los Angeles, IGPP, Los Angeles, CA 90095 USA.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
Univ Minnesota, Tate Lab Phys, Minneapolis, MN 55455 USA.
Lockheed Palo Alto Res Labs, Lockheed Martin, Palo Alto, CA 94304 USA.
Univ New Hampshire, Durham, NH 03824 USA.
RP Ergun, RE (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
RI Peterson, WK/A-8706-2009; Pfaff, Robert/F-5703-2012;
OI Peterson, WK/0000-0002-1513-6096; Pfaff, Robert/0000-0002-4881-9715;
Moebius, Eberhard/0000-0002-2745-6978; Cattell,
Cynthia/0000-0002-3805-320X
NR 24
TC 208
Z9 210
U1 0
U2 4
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 0094-8276
J9 GEOPHYS RES LETT
JI Geophys. Res. Lett.
PD JUN 15
PY 1998
VL 25
IS 12
BP 2025
EP 2028
DI 10.1029/98GL00635
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800004
ER
PT J
AU Mobius, E
Tang, L
Kistler, LM
Popecki, M
Lund, EJ
Klumpar, D
Peterson, W
Shelley, EG
Klecker, B
Hovestadt, D
Carlson, CW
Ergun, R
McFadden, JP
Mozer, F
Temerin, M
Cattell, C
Elphic, R
Strangeway, R
Pfaff, R
AF Mobius, E
Tang, L
Kistler, LM
Popecki, M
Lund, EJ
Klumpar, D
Peterson, W
Shelley, EG
Klecker, B
Hovestadt, D
Carlson, CW
Ergun, R
McFadden, JP
Mozer, F
Temerin, M
Cattell, C
Elphic, R
Strangeway, R
Pfaff, R
TI Species dependent energies in upward directed ion beams over auroral
arcs as observed with FAST TEAMS
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID ACCELERATION; WAVES; IONOSPHERE
AB Upward flowing field-aligned ion beams over auroral arcs have been observed with the 3-dimensional ion mass spectrograph TEAMS on FAST. We have performed a statistical study on a sample of 77 ion beams from the auroral campaign in early 1997. All observed beams contain substantial amounts of H+, He+ and O+. A clear ordering of the total energies according to mass is found, with H+ having the lowest and O+ the highest energy. The composition varies significantly from beam to beam, with O+/H+ ratios ranging from = 0.1 to 10. No variation of the energy ratio between species is observed as a function of relative abundance, These results are discussed in the light of earlier observations of higher energies for O(+ )in statistical studies of beams during solar minimum and attempts to explain this behavior in terms of beam instabilities.
C1 Univ New Hampshire, Dept Phys, Durham, NH 03824 USA.
Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA.
Lockheed Palo Alto Res Labs, Palo Alto, CA 94304 USA.
Max Planck Inst Extraterr Phys, D-85740 Garching, Germany.
Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Mobius, E (reprint author), Univ New Hampshire, Dept Phys, Durham, NH 03824 USA.
RI Peterson, WK/A-8706-2009; Pfaff, Robert/F-5703-2012;
OI Peterson, WK/0000-0002-1513-6096; Pfaff, Robert/0000-0002-4881-9715;
Moebius, Eberhard/0000-0002-2745-6978; Cattell,
Cynthia/0000-0002-3805-320X
NR 17
TC 19
Z9 20
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 JUN 15
PY 1998
VL 25
IS 12
BP 2029
EP 2032
DI 10.1029/98GL00381
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800005
ER
PT J
AU Elphic, RC
Bonnell, JW
Strangeway, RJ
Kepko, L
Ergun, RE
McFadden, JP
Carlson, CW
Peria, W
Cattell, CA
Klumpar, D
Shelley, E
Peterson, W
Moebius, E
Kistler, L
Pfaff, R
AF Elphic, RC
Bonnell, JW
Strangeway, RJ
Kepko, L
Ergun, RE
McFadden, JP
Carlson, CW
Peria, W
Cattell, CA
Klumpar, D
Shelley, E
Peterson, W
Moebius, E
Kistler, L
Pfaff, R
TI The auroral current circuit and field-aligned currents observed by FAST
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID CURRENT-VOLTAGE RELATIONSHIP; ELECTRIC-FIELDS; DE-2; IONOSPHERE;
REGIONS; ENERGY; MODEL; ARC
AB FAST observes signatures of small-scale downward-going current at the edges of the inverted-V regions where the primary (auroral) electrons are found. In the winter pre-midnight auroral zone these downward currents are carried by upward flowing low- and medium-energy (up to several keV) electron beams. FAST instrumentation shows agreement between the current densities inferred from both the electron distributions and gradients in the magnetic field. FAST data taken near apogee (similar to 4000-km altitude) commonly show downward current magnetic field deflections consistent with the observed upward flux of similar to 10(9) electrons cm(-2) s(-1), or current densities of several mu A m(-2). The electron, field-aligned current and electric field signatures indicate the downward currents may be associated with "black aurora" and auroral ionospheric cavities. The field-aligned voltage-current relationship in the downward current region is nonlinear.
C1 Univ Calif Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA.
Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA.
Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Univ Minnesota, Minneapolis, MN 55455 USA.
Lockheed Martin Palo Alto Res Labs, Palo Alto, CA 94304 USA.
Univ New Hampshire, Durham, NH 03824 USA.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Elphic, RC (reprint author), Univ Calif Los Alamos Natl Lab, Space & Atmospher Sci Grp, MS D466, Los Alamos, NM 87545 USA.
RI Kepko, Larry/D-7747-2012; Pfaff, Robert/F-5703-2012; Peterson,
WK/A-8706-2009;
OI Kepko, Larry/0000-0002-4911-8208; Pfaff, Robert/0000-0002-4881-9715;
Peterson, WK/0000-0002-1513-6096; Moebius, Eberhard/0000-0002-2745-6978;
Cattell, Cynthia/0000-0002-3805-320X
NR 20
TC 63
Z9 63
U1 1
U2 4
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 0094-8276
J9 GEOPHYS RES LETT
JI Geophys. Res. Lett.
PD JUN 15
PY 1998
VL 25
IS 12
BP 2033
EP 2036
DI 10.1029/98GL01158
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800006
ER
PT J
AU Pfaff, R
Clemmons, J
Carlson, C
Ergun, R
McFadden, J
Mozer, F
Temerin, M
Klumpar, D
Peterson, W
Shelley, E
Moebius, E
Kistler, L
Strangeway, R
Elphic, R
Cattell, C
AF Pfaff, R
Clemmons, J
Carlson, C
Ergun, R
McFadden, J
Mozer, F
Temerin, M
Klumpar, D
Peterson, W
Shelley, E
Moebius, E
Kistler, L
Strangeway, R
Elphic, R
Cattell, C
TI Initial FAST observations of acceleration processes in the cusp
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID POLAR CUSP; PRECIPITATION; FIELD; DE-1
AB FAST satellite observations during two encounters with the Earth's cusps near 4000 km are presented. In addition to precipitating magnetosheath particles with isotropic pitch angle distributions, the energetic particle data reveal upgoing ion beams, ion conics, downgoing "inverted-V" electron distributions, and very narrow, intense upgoing electron beams. A rich assortment of DC-coupled electric fields and plasma waves accompany these acceleration processes. In one example, steplike injections of magnetosheath ions are correlated with bursts of upgoing ion beams and downgoing electrons, suggesting that the currents associated with these injections set up local electric potential structures that subsequently drive the acceleration processes. The observations underscore the fact that the cusp is not merely a conduit for the passage of magnetosheath particles and fields, but contains a dynamic internal electrical structure that accelerates particles locally and may alter the precipitating magnetosheath particle populations themselves.
C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Lockheed Palo Alto Lab, Palo Alto, CA USA.
Univ New Hampshire, Durham, NH 03824 USA.
Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA.
Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA.
RP Pfaff, R (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RI Peterson, WK/A-8706-2009; Pfaff, Robert/F-5703-2012;
OI Peterson, WK/0000-0002-1513-6096; Pfaff, Robert/0000-0002-4881-9715;
Clemmons, James/0000-0002-5298-5222; Moebius,
Eberhard/0000-0002-2745-6978; Cattell, Cynthia/0000-0002-3805-320X
NR 9
TC 25
Z9 25
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 JUN 15
PY 1998
VL 25
IS 12
BP 2037
EP 2040
DI 10.1029/98GL00936
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800007
ER
PT J
AU Ergun, RE
Carlson, CW
McFadden, JP
Mozer, FS
Delory, GT
Peria, W
Chaston, CC
Temerin, M
Roth, I
Muschietti, L
Elphic, R
Strangeway, R
Pfaff, R
Cattell, CA
Klumpar, D
Shelley, E
Peterson, W
Moebius, E
Kistler, L
AF Ergun, RE
Carlson, CW
McFadden, JP
Mozer, FS
Delory, GT
Peria, W
Chaston, CC
Temerin, M
Roth, I
Muschietti, L
Elphic, R
Strangeway, R
Pfaff, R
Cattell, CA
Klumpar, D
Shelley, E
Peterson, W
Moebius, E
Kistler, L
TI FAST satellite observations of large-amplitude solitary structures
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID WAVES
AB We report observations of "fast solitary waves" that are ubiquitous in downward current regions of the mid-altitude auroral zone. The single-period structures have large amplitudes (up to 2.5 V/m), travel much faster than the ion acoustic speed, carry substantial potentials (up to similar to 100 Volts), and are associated with strong modulations of energetic electron fluxes. The amplitude and speed of the structures distinguishes them from ion-acoustic solitary waves or weak double layers. The electromagnetic signature appears to be that of an positive charge (electron hole) traveling anti-earthward. We present evidence that the structures are in or near regions of magnetic-field-aligned electric fields and propose that these nonlinear structures play a key role in supporting parallel electric fields in the downward current region of the auroral zone.
C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
Univ Calif Los Angeles, IGPP, Los Angeles, CA 90095 USA.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
Univ Minnesota, Tate Lab Phys, Minneapolis, MN 55455 USA.
Lockheed Palo Alto Res Labs, Lockheed Martin, Palo Alto, CA 94304 USA.
Univ New Hampshire, Durham, NH 03824 USA.
RP Ergun, RE (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
EM ree@ssl.berkeley.edu; cwc@ssl.berkeley.edu; mcfadden@ssl.berkeley.edu;
gdelory@ssl.berkeley.edu; peria@ssl.berkeley.edu; ccc@ssl.berkeley.edu;
temerin@ssl.berkeley.edu; ilan@ssl.berkeley.edu;
laurent@ssl.berkeley.edu; relphic@lanl.gov; strange@igpp.ucla.edu;
rob.pfaff@gsfc.nasa.gov; cattell@belka.spa.umn.edu;
klump@agena.space.lookhead.com; moebius@rotor.sr.unh.edu;
kistler@rotor.sr.unh.edu
RI Peterson, WK/A-8706-2009; Pfaff, Robert/F-5703-2012;
OI Peterson, WK/0000-0002-1513-6096; Pfaff, Robert/0000-0002-4881-9715;
Moebius, Eberhard/0000-0002-2745-6978; Cattell,
Cynthia/0000-0002-3805-320X
NR 15
TC 341
Z9 344
U1 1
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 JUN 15
PY 1998
VL 25
IS 12
BP 2041
EP 2044
DI 10.1029/98GL00636
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800008
ER
PT J
AU McFadden, JP
Carlson, CW
Ergun, RE
Chaston, CC
Mozer, FS
Temerin, M
Klumpar, DM
Shelley, EG
Peterson, WK
Moebius, E
Kistler, L
Elphic, R
Strangeway, R
Cattell, C
Pfaff, R
AF McFadden, JP
Carlson, CW
Ergun, RE
Chaston, CC
Mozer, FS
Temerin, M
Klumpar, DM
Shelley, EG
Peterson, WK
Moebius, E
Kistler, L
Elphic, R
Strangeway, R
Cattell, C
Pfaff, R
TI Electron modulation and ion cyclotron waves observed by FAST
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID POLAR MAGNETOSPHERE
AB New observations from the FAST satellite demonstrate strong wave-particle interactions between energetic electrons and H+ EMIC waves in inverted-V arcs. The intense waves are shown to occur in strong upward current regions which contain intense downgoing field-aligned electron fluxes. Electrons near the inverted-V spectral peak have large, factor of 2 to 10, coherent flux modulations at or near the wave frequency. The electron modulations are typically centered at about f(CH+)/2, where f(CH+) is the local H+ cyclotron frequency. The EMIC waves are broadbanded, extending from about 0.3f(CH+) to 0.7f(CH+). These waves also accelerate cold secondary electrons, forming counterstreaming field-aligned electrons at energies up to about 300 eV.In addition, electron modulations at f(CH+) are observed in the density cavities associated with upgoing ion beams. Intense waves at f(CH+) are simultaneously detected and shown to have a magnetic component similar to the EMIC waves.
C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Lockheed Martin Palo Alto Res Labs, Palo Alto, CA 94304 USA.
Univ New Hampshire, Durham, NH 03824 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
Univ Calif Los Angeles, Los Angeles, CA 90095 USA.
Univ Minnesota, Minneapolis, MN 55455 USA.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP McFadden, JP (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
RI Pfaff, Robert/F-5703-2012; Peterson, WK/A-8706-2009;
OI Pfaff, Robert/0000-0002-4881-9715; Peterson, WK/0000-0002-1513-6096;
Moebius, Eberhard/0000-0002-2745-6978; Cattell,
Cynthia/0000-0002-3805-320X
NR 8
TC 55
Z9 55
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 JUN 15
PY 1998
VL 25
IS 12
BP 2045
EP 2048
DI 10.1029/98GL00855
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800009
ER
PT J
AU Lund, EJ
Mobius, E
Tang, L
Kistler, LM
Popecki, MA
Klumpar, DM
Peterson, WK
Shelley, EG
Klecker, B
Hovestadt, D
Temerin, M
Ergun, RE
McFadden, JP
Carlson, CW
Mozer, FS
Elphic, RC
Strangeway, RJ
Cattell, CA
Pfaff, RF
AF Lund, EJ
Mobius, E
Tang, L
Kistler, LM
Popecki, MA
Klumpar, DM
Peterson, WK
Shelley, EG
Klecker, B
Hovestadt, D
Temerin, M
Ergun, RE
McFadden, JP
Carlson, CW
Mozer, FS
Elphic, RC
Strangeway, RJ
Cattell, CA
Pfaff, RF
TI FAST observations of preferentially accelerated He+ in association with
auroral electromagnetic ion cyclotron waves
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID FLICKERING AURORA; ELF WAVES; MECHANISM
AB The TEAMS instrument on the FAST satellite has detected events in which He+ ions are resonantly accelerated perpendicular to the magnetic field to energies of several keV. The events occur in association with electromagnetic ion cyclotron (EMIC) waves and conic distributions of up to a few hundred eV in H+ and a few keV in O+. Concentrations of Het can be significantly elevated during the events. Our interpretation is that the He+ ions are accelerated through a cyclotron resonance with the waves. This acceleration is similar to a proposed mechanism for selective ion acceleration in impulsive solar flares.
C1 Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA.
Univ New Hampshire, Dept Phys, Durham, NH 03824 USA.
Lockheed Martin Palo Alto Res Lab, Palo Alto, CA 94304 USA.
Max Planck Inst Extraterr Phys, D-85740 Garching, Germany.
Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA.
NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA.
RP Lund, EJ (reprint author), Univ New Hampshire, Ctr Space Sci, Morse Hall, Durham, NH 03824 USA.
EM Eric.Lund@unh.edu
RI Pfaff, Robert/F-5703-2012; Peterson, WK/A-8706-2009;
OI Pfaff, Robert/0000-0002-4881-9715; Peterson, WK/0000-0002-1513-6096;
Lund, Eric/0000-0003-1312-9375; Moebius, Eberhard/0000-0002-2745-6978;
Cattell, Cynthia/0000-0002-3805-320X
NR 19
TC 29
Z9 29
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 JUN 15
PY 1998
VL 25
IS 12
BP 2049
EP 2052
DI 10.1029/98GL00304
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA ZV204
UT WOS:000074280800010
ER
PT J
AU Cattell, C
Bergmann, R
Sigsbee, K
Carlson, C
Chaston, C
Ergun, R
McFadden, J
Mozer, FS
Temerin, M
Strangeway, R
Elphic, R
Kistler, L
Moebius, E
Tang, L
Klumpar, D
Pfaff, R
AF Cattell, C
Bergmann, R
Sigsbee, K
Carlson, C
Chaston, C
Ergun, R
McFadden, J
Mozer, FS
Temerin, M
Strangeway, R
Elphic, R
Kistler, L
Moebius, E
Tang, L
Klumpar, D
Pfaff, R
TI The association of electrostatic ion cyclotron waves, ion and electron
beams and field-aligned currents: FAST observations of an auroral zone
crossing near midnight
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID HYDROGEN CYCLOTRON; INSTABILITIES; LINES; H+
AB FAST particle and wave data for a single nightside auroral zone crossing are utilized to examine the free energy source for electrostatic ion cyclotron (EIC) waves. Comparisons of the unstable wave modes, obtained by an electrostatic linear dispersion relation solver, to the observed waves for two intervals with upflowing ion beams and two with upflowing electron beams are consistent with the conclusion that the observed waves near the cyclotron frequencies are EIC which are driven by the electron drift both in the upgoing ion beam regions and in the upgoing electron regions. A limitation is that the drifting bi-Maxwellian model used in the dispersion relation is not a good match to the observed upflowing electron distributions. The observed ion beams do not drive EIC waves; however, the relative drift of the various ion species comprising the ion beam can drive low frequency (