FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Cavalleri, M Odelius, M Nordlund, D Nilsson, A Pettersson, LGM AF Cavalleri, M Odelius, M Nordlund, D Nilsson, A Pettersson, LGM TI Half or full core hole in density functional theory X-ray absorption spectrum calculations of water? SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID HYDROGEN-BOND NETWORK; LIQUID WATER; FINE-STRUCTURE; REARRANGEMENTS; EXCITATION; ENERGETICS; MOLECULES; BREAKING; ATOMS; ICE AB We analyze the performance of two different core-hole potentials in the theoretical modeling of XAS of ice, liquid and gas phase water; the use of a full core-hole (ITCH) in the calculations, as suggested by Hetenyi et al. [B. Hetenyi, F. De Angelis, P. Giamozzi and R. Car, J. Chem. Phys., 2004, 120(18), 8632], gives poor agreement with experiment in terms of intensity distribution as well as transition energies, while the half core hole (HCH) potential, in the case of water, provides a better compromise between initial and final state effects, leading to good agreement with the experimental data. C1 Stockholm Univ, AlbaNova Univ Ctr, S-10691 Stockholm, Sweden. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Pettersson, LGM (reprint author), Stockholm Univ, AlbaNova Univ Ctr, S-10691 Stockholm, Sweden. EM lgm@physto.se RI Cavalleri, Matteo/A-7689-2008; Nordlund, Dennis/A-8902-2008; Nilsson, Anders/E-1943-2011; Pettersson, Lars/F-8428-2011; Pettersson, Lars/J-4925-2013; Odelius, Michael/A-7628-2014 OI Nordlund, Dennis/0000-0001-9524-6908; Nilsson, Anders/0000-0003-1968-8696; Pettersson, Lars/0000-0003-1133-9934; Odelius, Michael/0000-0002-7023-2486 NR 31 TC 80 Z9 80 U1 1 U2 8 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 J9 PHYS CHEM CHEM PHYS JI Phys. Chem. Chem. Phys. PY 2005 VL 7 IS 15 BP 2854 EP 2858 DI 10.1039/b505723j PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 946TW UT WOS:000230596900019 PM 16189603 ER PT J AU Huang, SJ Huh, S Lo, PS Liu, SH Lin, VSY Liu, SB AF Huang, SJ Huh, S Lo, PS Liu, SH Lin, VSY Liu, SB TI Hyperpolarized Xe-129 NMR investigation of multifunctional organic/inorganic hybrid mesoporous silica materials SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; LASER-POLARIZED XE-129; MOLECULAR-SIEVES; SPIN-EXCHANGE; MICROPOROUS SOLIDS; CONTINUOUS-FLOW; ADSORBED XENON; NOBLE-GASES; THIN-FILMS; SPECTROSCOPY AB An extensive study has been made on a series of multifunctional mesoporous silica materials, prepared by introducing two different organoalkoxysilanes, namely 3-[2-(2-aminoethylamino) ethylamino] propyltrimethoxysilane (AEPTMS) and 3-cyanopropyltriethoxysilane (CPTES) during the base-catalyzed condensation of tetraethoxysilane (TEOS), using the variable-temperature (VT) hyperpolarized (HP) Xe-129 NMR technique. VT HP-Xe-129 NMR chemical shift measurements of adsorbed xenon revealed that surface properties as well as functionality of these AEP/CP-functionalized microparticles ( MP) could be controlled by varying the AEPTMS/CPTES ratio in the starting solution during synthesis. Additional chemical shift contribution due to Xe-moiety interactions was observed for monofunctional AEP-MP and CP-MP as well as for bifunctional AEP/CP- MP samples. In particular, unlike CP-MP that has a shorter organic backbone on the silica surface, the amino groups in the AEP chain tends to interact with the silanol groups on the silica surface causing backbone bending and hence formation of secondary pores in AEP-MP, as indicated by additional shoulder peak at lower field in the room-temperature Xe-129 NMR spectrum. The exchange processes of xenon in different adsorption regions were also verified by 2D EXSY HP-Xe-129 NMR spectroscopy. It is also found that subsequent removal of functional moieties by calcination treatment tends to result in a more severe surface roughness on the pore walls in bifunctional samples compared to monofunctional ones. The effect of hydrophobicity/hydrophilicity of the organoalkoxysilanes on the formation, pore structure and surface property of these functionalized mesoporous silica materials are also discussed. C1 Acad Sinica, Inst Atom & Mol Sci, Taipei 106, Taiwan. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, USDOE, Ames, IA 50011 USA. RP Acad Sinica, Inst Atom & Mol Sci, POB 23-166, Taipei 106, Taiwan. EM vsylin@iastate.edu; sbliu@sinica.edu.tw RI Liu, Shou-Heng/B-3391-2008; Liu, Shang-Bin/F-7603-2012; HUH, SEONG/E-5192-2011; OI Liu, Shou-Heng/0000-0002-4852-874X; Liu, Shang-Bin/0000-0001-5858-0608; Huh, Seong/0000-0001-7894-8422 NR 73 TC 20 Z9 21 U1 0 U2 16 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 EI 1463-9084 J9 PHYS CHEM CHEM PHYS JI Phys. Chem. Chem. Phys. PY 2005 VL 7 IS 16 BP 3080 EP 3087 DI 10.1039/b506280b PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 951LH UT WOS:000230931200013 PM 16186913 ER PT J AU Greathouse, JA Cygan, RT AF Greathouse, JA Cygan, RT TI Molecular dynamics simulation of uranyl(VI) adsorption equilibria onto an external montmorillonite surface SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID AQUEOUS-SOLUTIONS; SORPTION COMPLEXES; URANIUM SORPTION; MONTE-CARLO; COMPUTER-SIMULATION; CARBONATE COMPLEXES; U(VI) SORPTION; EXAFS; WATER; CLAY AB We used molecular dynamics simulations to study the adsorption of aqueous uranyl species (UO22+) onto clay mineral surfaces in the presence of sodium counterions and carbonato ligands. The large system size (10 000 atoms) and long simulation times (10 ns) allowed us to investigate the thermodynamics of ion adsorption, and the atomistic detail provided clues for the observed adsorption behavior. The model system consisted of the basal surface of a low-charge Na-montmorillonite clay in contact with aqueous uranyl carbonate solutions with concentrations of 0.027 M, 0.081 M, and 0.162 M. Periodic boundary conditions were used in the simulations to better represent an aqueous solution interacting with an external clay surface. Uranyl adsorption tendency was found to decrease as the aqueous uranyl carbonate concentration was increased, while sodium adsorption remained constant. The observed behavior is explained by physical and chemical effects. As the ionic strength of the aqueous solution was increased, electrostatic factors prevented further uranyl adsorption once the surface charge had been neutralized. Additionally, the formation of aqueous uranyl carbonate complexes, including uranyl carbonato oligomers, contributed to the decreased uranyl adsorption tendency. C1 Sandia Natl Labs, Dept Geochem, Albuquerque, NM 87185 USA. RP Greathouse, JA (reprint author), Sandia Natl Labs, Dept Geochem, Albuquerque, NM 87185 USA. EM jagreat@sandia.gov NR 76 TC 78 Z9 84 U1 4 U2 39 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 J9 PHYS CHEM CHEM PHYS JI Phys. Chem. Chem. Phys. PY 2005 VL 7 IS 20 BP 3580 EP 3586 DI 10.1039/b509307d PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 970KQ UT WOS:000232307900010 PM 16294234 ER PT J AU McIntire, TM Lea, AS Gaspar, DJ Jaitly, N Dubowski, Y Li, QQ Finlayson-Pitts, BJ AF McIntire, TM Lea, AS Gaspar, DJ Jaitly, N Dubowski, Y Li, QQ Finlayson-Pitts, BJ TI Unusual aggregates from the oxidation of alkene self-assembled monolayers: a previously unrecognized mechanism for SAM ozonolysis? SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID SECONDARY ORGANIC AEROSOL; CATALYZED HETEROGENEOUS REACTIONS; GAS-PHASE OZONE; OLEIC-ACID; REACTIVE UPTAKE; THIN-FILMS; ALKANETHIOL MONOLAYERS; MINERAL DUST; PARTICLES; PRODUCTS AB Self-assembled monolayers (SAMs) of vinyl-terminated 3- and 8-carbon compounds were generated on Si substrates and reacted at room temperature with similar to 1 ppm gaseous O-3. A combination of atomic force microscopy (AFM), scanning electron microscopy (SEM), Auger electron spectroscopy (AES) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) was used to study the surface composition and morphology after oxidation. A distribution of large (similar to 0.1-10 mu m) organic aggregates was formed, while the surrounding substrate became depleted of carbon compared to the unreacted SAM. This highly unusual result establishes that the mechanism of ozonolysis of alkene SAMs must have a channel that is unique compared to that in the gas phase or in solution, and may involve polymerization induced by the Criegee intermediate (CI). Oxidation at 60% RH led to the formation of a number of smaller aggregates, suggesting water intercepted the CI in competition with aggregate formation. The uptake of water, measured using transmission FTIR, was not increased upon oxidation of these films. In conjunction with literature reports of polymer formation from VOC-NOx photooxidations, these results suggest that formation of aggregates and polymers in the atmosphere is much more widespread than previously thought. The implications for the ozonolysis of alkenes on surfaces, for the transformation of organics in the atmosphere, and for the reactions and stability of unsaturated SAMs, are discussed. C1 Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Technion Israel Inst Technol, Fac Environm & Civil Engn, IL-32000 Haifa, Israel. RP Finlayson-Pitts, BJ (reprint author), Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. EM bjfinlay@uci.edu RI Gaspar, Dan/H-6166-2011; OI Gaspar, Daniel/0000-0002-8089-810X; Lea, Alan/0000-0002-4232-1553 NR 58 TC 34 Z9 34 U1 5 U2 30 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 J9 PHYS CHEM CHEM PHYS JI Phys. Chem. Chem. Phys. PY 2005 VL 7 IS 20 BP 3605 EP 3609 DI 10.1039/b508147e PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 970KQ UT WOS:000232307900014 PM 16294238 ER PT J AU Smith, JA Josowicz, M Engelhard, M Baer, DR Janata, J AF Smith, JA Josowicz, M Engelhard, M Baer, DR Janata, J TI Gold-polyaniline composites - Part II. Effects of nanometer sized particles SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID METAL-CLUSTERS; ELECTRONIC-STRUCTURE; PHOTOEMISSION; SHIFTS; TETRACHLOROAURATE; SUBSTRATE; CATALYSTS; OXIDES AB The amount of electronic charge transferred between gold particles and polyaniline depends not only on the electron affinity of the two materials but also on the size of the gold particles. As measured by X-ray photoelectron spectroscopy, for particles < similar to 5 nm the binding energy of the electrons is size dependent. This "nano-effect'' has its origin in the electrostatics of particles. It is demonstrated as a measurable shift of the binding energy of the Au-4f7/2 photoelectrons emitted from Au particles embedded in a polyaniline matrix. Gold nanoparticle size was evaluated by high resolution transmission electron microscopy. C1 Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. EM don.baer@pnl.gov; jiri.janata@chemistry.gatech.edu RI Engelhard, Mark/F-1317-2010; Baer, Donald/J-6191-2013; OI Baer, Donald/0000-0003-0875-5961; Engelhard, Mark/0000-0002-5543-0812 NR 23 TC 32 Z9 32 U1 2 U2 16 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 EI 1463-9084 J9 PHYS CHEM CHEM PHYS JI Phys. Chem. Chem. Phys. PY 2005 VL 7 IS 20 BP 3619 EP 3625 DI 10.1039/b507099f PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 970KQ UT WOS:000232307900017 PM 16294241 ER PT J AU Wang, H Lu, WC Sun, CC Wang, CZ Ho, KM AF Wang, H Lu, WC Sun, CC Wang, CZ Ho, KM TI Structure and stability of oxygen adsorption on Si-n (n=5-10) clusters SO PHYSICAL CHEMISTRY CHEMICAL PHYSICS LA English DT Article ID SILICON-OXIDE CLUSTERS; MINIMAL BASIS-SETS; SEMICONDUCTOR CLUSTERS; AB-INITIO; MOLECULAR-DYNAMICS; SI-12 CLUSTER; CHEMISTRY; IONS; CHEMISORPTION; REACTIVITY AB The structures, binding energies, and electronic properties of one oxygen atom (O) and two oxygen atoms (2O) adsorption on silicon clusters Sin with n ranging from 5 to 10 are studied systematically by ab initio calculations. Twelve stable structures are obtained, two of which are in agreement with those reported in previous literature and the others are new structures that have not been proposed before. Further investigations on the fragmentations of SinO and SinO2 (n = 5-10) clusters indicate that the pathways SinO -> Sin-1 + SiO and SinO2 -> Sin-2 + Si2O2 are most favorable from thermodynamic viewpoint. Among the studied silicon oxide clusters, Si8O, Si9O, Si5O2 and Si8O2 correspond to large adsorption energies of silicon clusters with respect to O or 2O, while Si8O, with the smallest dissociation energy, has a tendency to separate into Si-7 + SiO. Using the recently developed quasi-atomic minimal-basis-orbital method, we have also calculated the unsaturated valences of the neutral Si-n clusters. Our calculation results show that the Si atoms which have the largest unsaturated valences are more attractive to O atom. Placing O atom right around the Si atoms with the largest unsaturated valences usually leads to stable structures of the silicon oxide clusters. C1 Jilin Univ, Inst Theoret Chem, State Key Lab Theoret & Computat Chem, Changchun 130023, Peoples R China. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Lu, WC (reprint author), Jilin Univ, Inst Theoret Chem, State Key Lab Theoret & Computat Chem, Changchun 130023, Peoples R China. EM wencailu@yahoo.com OI Wang, Chong/0000-0003-4489-4344 NR 46 TC 5 Z9 5 U1 0 U2 8 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1463-9076 J9 PHYS CHEM CHEM PHYS JI Phys. Chem. Chem. Phys. PY 2005 VL 7 IS 22 BP 3811 EP 3818 DI 10.1039/b509813k PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 979MS UT WOS:000232946700005 PM 16358030 ER PT J AU Budker, D Hollberg, L Kimball, DF Kitching, J Pustelny, S Yashchuk, VV AF Budker, D Hollberg, L Kimball, DF Kitching, J Pustelny, S Yashchuk, VV TI Microwave transitions and nonlinear magneto-optical rotation in anti-relaxation-coated cells SO PHYSICAL REVIEW A LA English DT Article ID FREQUENCY STANDARDS; HYPERFINE TRANSITION; GROUND-STATE; ATOMS; MAGNETOMETER; SHIFTS; RB-85 AB Using laser optical pumping, widths and frequency shifts are determined for microwave transitions between ground-state hyperfine components of Rb-85 and Rb-87 atoms contained in vapor cells with alkane antirelaxation coatings. The results are compared with data on Zeeman relaxation obtained in nonlinear magneto-optical rotation experiments, a comparison important for quantitative understanding of spin-relaxation mechanisms in coated cells. By comparing cells manufactured over a 40-year period we demonstrate the long-term stability of coated cells, an important property for atomic clocks and magnetometers. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Natl Inst Stand & Technol, Boulder, CO 80305 USA. Jagiellonian Univ, Inst Fiz M Smoluchowskiego, PL-30059 Krakow, Poland. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source Div, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM budker@socrates.berkeley.edu; kitching@boulder.nist.gov RI Budker, Dmitry/F-7580-2016 OI Budker, Dmitry/0000-0002-7356-4814 NR 39 TC 75 Z9 75 U1 0 U2 8 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 JAN PY 2005 VL 71 IS 1 AR 012903 DI 10.1103/PhysRevA.71.012903 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 901LF UT WOS:000227283300093 ER PT J AU Fournier, KB Hansen, SB AF Fournier, KB Hansen, SB TI Resolution of the long-standing overprediction of the resonance to intercombination line-intensity ratio in mid-Z neonlike ions SO PHYSICAL REVIEW A LA English DT Article ID X-RAY-SPECTRA; TRANSMISSION GRATING SPECTROMETER; ELECTRON-IMPACT EXCITATION; LASER-PRODUCED PLASMAS; FE-XVII; COLLISION STRENGTHS; ATOMIC DATA; LABORATORY MEASUREMENTS; ISOELECTRONIC SEQUENCE; OSCILLATOR-STRENGTHS AB The Ne-like resonance 2p(6) S-1-2p(5)3d P-1 (3C) to intercombination 2p(6) S-1-2p(5)3d D-3 (3D) line-intensity ratio, R(3C/3D), has been extensively studied through high-accuracy measurements and calculations of atomic structure and collision cross sections. However, even state-of-the-art relativistic multiconfiguration atomic-physics codes generally predict values of R(3C/3D) that are significantly larger than those observed in coronal-density experiments. In this paper, predictions of R(3C/3D) across the Ne-like isoelectronic sequence from chromium to silver are brought into agreement with coronal-density experimental measurements in two steps: first by including a semiempirical correction in the collisional atomic data due to configuration-interaction effects, and next by including the effects of cascades on the upper level populations. The configuration-interaction correction is inspired by the observation that nearly all data-production codes fail to predict R(3C/3D) correctly and is justified theoretically by a careful analysis of configuration-interaction contributions to level energies. The dependence of R(3C/3D) with electron density and its agreement with moderate-density measurements are shown. A brief description of the application of our technique to line ratios in He- and Ni-like x-ray spectra is also given. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, POB 808,L-473, Livermore, CA 94550 USA. NR 87 TC 12 Z9 12 U1 0 U2 3 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 JAN PY 2005 VL 71 IS 1 AR 012717 DI 10.1103/PhysRevA.71.012717 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 901LF UT WOS:000227283300090 ER PT J AU Horner, DA McCurdy, CW Rescigno, TN AF Horner, DA McCurdy, CW Rescigno, TN TI Electron-impact excitation autoionization of helium in the S-wave limit SO PHYSICAL REVIEW A LA English DT Article ID (2S2P)P-3 STATES; CROSS-SECTIONS; MODEL; HE AB Excitation of the autoionizing states of helium by electron impact is shown in calculations in the S-wave limit to leave a clear signature in the singly differential cross section for the (e, 2e) process. It is suggested that such behavior should be seen generally in (e,2e) experiments on atoms that measure the single differential cross section. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. RP Horner, DA (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 20 TC 9 Z9 9 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD JAN PY 2005 VL 71 IS 1 AR 010701 DI 10.1103/PhysRevA.71.010701 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 901LF UT WOS:000227283300004 ER PT J AU Horner, DA McCurdy, CW Rescigno, TN AF Horner, DA McCurdy, CW Rescigno, TN TI Electron-helium scattering in the S-wave model using exterior complex scaling SO PHYSICAL REVIEW A LA English DT Article ID SCHRODINGER-EQUATION; IMPACT IONIZATION; COUPLING METHOD; HYDROGEN; BREAKUP AB Electron-impact excitation and ionization of helium is studied in the S-wave model. The problem is treated in full dimensionality using a time-dependent formulation of the exterior complex scaling method that does not involve the solution of large linear systems of equations. We discuss the steps that must be taken to compute stable ionization amplitudes. We present total excitation, total ionization, and single differential cross sections from the ground and n=2 excited states and compare our results with those obtained by others using a frozen-core model. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. RP Horner, DA (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM dahorner@lbl.gov; cwmccurdy@lbl.gov; tnrescigno@lbl.gov NR 24 TC 26 Z9 26 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 JAN PY 2005 VL 71 IS 1 AR 012701 DI 10.1103/PhysRevA.71.012701 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 901LF UT WOS:000227283300074 ER PT J AU Aryanpour, K Maier, TA Jarrell, M AF Aryanpour, K Maier, TA Jarrell, M TI Comment on "Cluster methods for strongly correlated electron systems" SO PHYSICAL REVIEW B LA English DT Editorial Material ID HUBBARD-MODEL; DIMENSIONS; SUPERCONDUCTORS; FERMIONS; LATTICE; LIMIT AB We comment on the article by Biroli and Kotliar [Phys. Rev. B 65, 155112 (2002)] in which they make a comparison between two cluster techniques, the cellular dynamical mean field theory (CDMFT) and the dynamical cluster approximation (DCA). Based upon an incorrect implementation of the DCA technique in their work, they conclude that the CDMFT is a faster converging technique than the DCA. We present the correct DCA prescription for the particular model Hamiltonian studied in their article and conclude that the DCA, once implemented correctly, is a faster converging technique for the quantities averaged over the cluster. C1 Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Calif Davis, Davis, CA 95616 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Aryanpour, K (reprint author), Univ Cincinnati, Cincinnati, OH 45221 USA. RI Maier, Thomas/F-6759-2012 OI Maier, Thomas/0000-0002-1424-9996 NR 16 TC 15 Z9 15 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 3 AR 037101 DI 10.1103/PhysRevB.71.037101 PG 3 WC Physics, Condensed Matter SC Physics GA 893RC UT WOS:000226735900149 ER PT J AU Bauer, ED Sidorov, VA Bobev, S Mixson, DJ Thompson, JD Sarrao, JL Hundley, MF AF Bauer, ED Sidorov, VA Bobev, S Mixson, DJ Thompson, JD Sarrao, JL Hundley, MF TI High-pressure investigation of the heavy-fermion antiferromagnet U3Ni5Al19 SO PHYSICAL REVIEW B LA English DT Article ID LIQUID BEHAVIOR; ELECTRICAL-RESISTIVITY; PHASE-TRANSITION; CRITICAL-POINTS; KONDO DISORDER; SUPERCONDUCTIVITY; TEMPERATURE; FERROMAGNETISM; SYSTEMS; UGE2 AB Measurements of magnetic susceptibility, specific heat, and electrical resistivity at applied pressures up to 55 kbar have been carried out on single crystals of the heavy-fermion antiferromagnet U3Ni5Al19, which crystallizes in the Gd3Ni5Al19 orthorhombic structure with two inequivalent U sites. At ambient pressure, an upturn of the specific heat and T-linear electrical resistivity below 5 K indicate non-Fermi liquid (NFL) behavior in the presence of bulk antiferromagnetic order at T-N=23 K. Electrical resistivity measurements reveal a crossover from non-Fermi liquid to Fermi liquid behavior at intermediate pressures between 46 and 51 kbar, followed by a return to NFL T-3/2 behavior at higher pressures. These results provide evidence for an ambient pressure quantum critical point and an additional antiferromagnetic instability at P(c)approximate to60 kbar. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. RP Bauer, ED (reprint author), Russian Acad Sci, Inst High Pressure Phys, Troitsk 142190, Russia. RI Bauer, Eric/D-7212-2011 NR 25 TC 8 Z9 8 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014419 DI 10.1103/PhysRevB.71.014419 PG 5 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100099 ER PT J AU Baumbach, R Bridges, F Downward, L Cao, D Chesler, P Sales, B AF Baumbach, R Bridges, F Downward, L Cao, D Chesler, P Sales, B TI Off-center phonon scattering sites in Eu8Ga16Ge30 and Sr8Ga16Ge30 SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION FINE-STRUCTURE; FILLED SKUTTERUDITE COMPOUNDS; ALKALINE-EARTH; THERMAL-CONDUCTIVITY; THERMOELECTRIC PROPERTIES; CLATHRATE EU8GA16GE30; STRUCTURAL DISORDER; CRYSTAL-STRUCTURE; GE; SEMICONDUCTORS AB We present a detailed extended x-ray absorption fine structure (EXAFS) analysis of the thermoelectric clathrates Eu8Ga16Ge30 and Sr8Ga16Ge30, both of which have an unusually low thermal conductivity attributed to a "rattler" motion of the filler atoms Eu and Sr. The EXAFS results show that the Ga/Ge lattice is quite stiff with a high correlated Debye temperature similar to400 K. Eu is on-center in the site 1 cage but off-center (0.445+/-0.020 A) in the large cage called the Eu2 site. The results for Sr are similar, but similar to75% are off-center 0.40+/-0.05 A and similar to25% are on-center in the Sr2 site. Both results are in reasonable agreement with diffraction results. The temperature dependence of the nearest neighbor pair distribution widths yield low Einstein temperatures (80+/-10 and 100+/-10 K for Eu1 and Sr1, respectively, and 95+/-10 and 125+/-10 K for the shortest Eu2-Ga/Ge and Sr2-Ga/Ge pairs). In contrast, the more distant Eu2/Sr2-Ga/Ge pair distributions within the Eu2/Sr2 cage are strongly disordered even at low T, indicating considerable local disorder. This indicates that the off-center Eu or Sr atom is bonded to the side of the site 2 cage. This has two important implications for the thermal conductivity: it increases the coupling between the "rattler" vibrations and the lattice phonons and it introduces a symmetry-breaking large mass defect. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Baumbach, R (reprint author), Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. RI Baumbach, Ryan/C-5528-2012 NR 39 TC 47 Z9 47 U1 2 U2 19 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 024202 DI 10.1103/PhysRevB.71.024202 PG 19 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400037 ER PT J AU Berman, GP Bishop, AR Kamenev, DI Trombettoni, A AF Berman, GP Bishop, AR Kamenev, DI Trombettoni, A TI Quantum logic operations and creation of entanglement in a scalable superconducting quantum computer with long-range constant interaction between qubits SO PHYSICAL REVIEW B LA English DT Article ID JOSEPHSON-JUNCTION; STATES; OSCILLATIONS AB We consider a one-dimensional chain of many superconducting quantum interference devices (SQUIDs), serving as charge qubits. Each SQUID is coupled to its nearest neighbor through constant capacitances. We study the quantum logic operations and implementation of entanglement in this system. Arrays with two and three qubits are considered in detail. We show that the creation of entanglement with an arbitrary number of qubits can be implemented, without systematic errors, even when the coupling between qubits is not small. A relatively large coupling constant allows one to increase the clock speed of the quantum computer. We analytically and numerically demonstrate the creation of the entanglement for this case, which can be a good test for the experimental implementation of a relatively simple quantum protocol with many qubits. The logic operations in a system with long-range interaction are not universal. We discuss a possible application of our approach for implementing universal quantum logic for more complex algorithms by decreasing the coupling constant and, correspondingly, decreasing the clock speed. The errors introduced by the long-range interaction for the universal logic gates are estimated analytically and calculated numerically. Our results can be useful for experimental implementation of quantum algorithms using controlled magnetic fluxes and gate voltages applied to the SQUIDs. The algorithms discussed in this paper can be implemented using already existing technologies in superconducting systems with constant interqubit coupling. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Parma, INFM, I-43100 Parma, Italy. Univ Parma, Dipartimento Fis, I-43100 Parma, Italy. RP Berman, GP (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 22 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014523 DI 10.1103/PhysRevB.71.014523 PG 11 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100149 ER PT J AU Bester, G Zunger, A AF Bester, G Zunger, A TI Cylindrically shaped zinc-blende semiconductor quantum dots do not have cylindrical symmetry: Atomistic symmetry, atomic relaxation, and piezoelectric effects SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; NONUNIFORM COMPOSITION; STRAIN DISTRIBUTION; WELL STRUCTURES; FIELD; GAAS; POLARIZATION; TRANSITION; 8-BAND; PHOTOREFLECTANCE AB Self-assembled quantum dots are often modeled by continuum models (effective mass or k.p) that assume the symmetry of the dot to be that of its overall geometric shape. Lens-shaped or conical dots are thus assumed to have continuous cylindrical symmetry C-infinityv, whereas pyramidal dots are assumed to have C-4v symmetry. However, considering that the III-V dots are made of atoms arranged on the (relaxed) positions of a zinc-blende lattice, one would expect the highest possible symmetry in these structures to be C-2v. In this symmetry group all states are singly degenerate and there are no a priori reason to expect, e.g., the electron P states (usually the second and third electron levels of dominant orbital P character) to be degenerate. Continuum models, however, predict these states to be energetically degenerate unless an irregular shape is postulated. We show that, in fact, the true (atomistic) symmetry of the dots is revealed when the effects of (i) interfacial symmetry, (ii) atomistic strain, and (iii) piezoelectricity are taken into account. We quantify the contributions of each of these effects separately by calculating the splitting of electron P levels for different dot shapes at different levels of theory. We find that for an ideal square-based pyramidal InAs/GaAs dot the interfacial symmetry of the unrelaxed dot splits the P level by 3.9 meV, atomistic relaxation adds a splitting of 18.3 meV (zero if continuum elasticity is used to calculate strain) and piezoelectricity reduces the splitting by -8.4 meV, for a total splitting of 13.8 meV. We further show that the atomistic effects (i) and (ii) favor an orientation of the electron wave functions along the [1 (1) over bar0] direction while effect (iii) favors the [110] direction. Whereas effects (i) + (ii) prevail for a pyramidal dot, for a lens shaped dot, effect (iii) is dominant. We show that the 8-band k.p method, applied to pyramidal InAs/GaAs dots describes incorrectly the splitting and order of P levels (-9 meV instead of 14 meV splitting) and yields the orientation [110] instead of [1 (1) over bar0]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Schaff, William/B-5839-2009; Bester, Gabriel/I-4414-2012; Zunger, Alex/A-6733-2013 OI Bester, Gabriel/0000-0003-2304-0817; NR 62 TC 153 Z9 154 U1 1 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045318 DI 10.1103/PhysRevB.71.045318 PG 12 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200084 ER PT J AU Bhaseen, MJ Essler, FHL Grage, A AF Bhaseen, MJ Essler, FHL Grage, A TI Itinerancy effects on spin correlations in one-dimensional Mott insulators SO PHYSICAL REVIEW B LA English DT Article ID HUBBARD-MODEL; EXCITATION SPECTRUM; SCATTERING MATRIX; CHAIN; SRCUO2 AB We consider spin correlations in the one-dimensional (1D) half-filled repulsive Hubbard model. For very large values of the on-site repulsion U the spin correlations are dominated by virtual hopping processes of electrons and are described in terms of a spin-1/2 Heisenberg chain. As U is decreased real hopping processes of electrons become important and eventually dominate the spin response. We discuss the evolution of the dynamical structure factor as a function of U. We comment on the relevance of our results for inelastic neutron-scattering experiments on quasi-1D materials. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Marburg, Fachbereich Phys, D-35032 Marburg, Germany. RP Bhaseen, MJ (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 17 TC 7 Z9 7 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 020405 DI 10.1103/PhysRevB.71.020405 PG 4 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400008 ER PT J AU Bondarchuk, O Dougherty, DB Degawa, M Williams, ED Constantin, M Dasgupta, C Das Sarma, S AF Bondarchuk, O Dougherty, DB Degawa, M Williams, ED Constantin, M Dasgupta, C Das Sarma, S TI Correlation time for step structural fluctuations SO PHYSICAL REVIEW B LA English DT Article ID VICINAL SURFACES; DIFFUSION; DYNAMICS; ISLANDS; SI(111) AB Time-dependent scanning tunneling microscopy has been used to evaluate step fluctuations as a function of temperature (300-450 K) on Ag(111) films grown on mica. The temporal correlation function scales as a power law in time t(1/n) with measured values of 1/n varying over a range of 0.19+/-0.04 to 0.29+/-0.04 with no correlation on temperature. The average value of 1/n=0.24+/-0.01 is consistent with step-edge diffusion limited fluctuations (n=z=4, conserved noise). The magnitude of the time correlation function and the width of the fluctuations both scale with temperature with the same apparent activation energy of E-eff=0.21+/-0.02 eV, indicating that the correlation time is at most weakly temperature dependent. Direct analysis of the autocorrelation function confirms that the correlation time is at most weakly temperature dependent, and thus the apparent correlation length is strongly temperature dependent. This behavior can be reproduced by assuming that the apparent correlation length is governed by the longest wavelength of step fluctuations that can be sampled in the measurement time interval. Evaluation of the correlation time for previous measurements for Al/Si(111) (z=2) yields the same conclusion about measurement time interval. In both cases the ratio of the measurement time to the effective correlation time is on the order of 10. C1 Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. Univ Maryland, Condensed Matter Theory Ctr, College Pk, MD 20742 USA. Indian Inst Sci, Dept Phys, Bangalore 560012, Karnataka, India. RP Bondarchuk, O (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Das Sarma, Sankar/B-2400-2009; OI Das Sarma, Sankar/0000-0002-0439-986X; Bondarchuk, Oleksandr/0000-0001-7380-8930 NR 25 TC 24 Z9 24 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045426 DI 10.1103/PhysRevB.71.045426 PG 10 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200133 ER PT J AU Boubeta, CM Clavero, C Garcia-Martin, JM Armelles, G Cebollada, A Balcells, L Menendez, JL Peiro, F Cornet, A Toney, MF AF Boubeta, CM Clavero, C Garcia-Martin, JM Armelles, G Cebollada, A Balcells, L Menendez, JL Peiro, F Cornet, A Toney, MF TI Coverage effects on the magnetism of Fe/MgO(001) ultrathin films SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-BEAM EPITAXY; X-RAY REFLECTIVITY; FE FILMS; GROWTH MODE; BCC FE; ANISOTROPIES; MGO; MGO(001); SURFACE; MAGNETIZATION AB Different aspects of the structure-magnetism and morphology-magnetism correlation in the ultrathin limit are studied in epitaxial Fe films grown on MgO(001). In the initial stages of growth the presence of substrate steps, intrinsically higher than an Fe atomic layer, prevent the connection between Fe islands and hence the formation of large volume magnetic regions. This is proposed as an explanation to the superparamagnetic nature of ultrathin Fe films grown on MgO in addition to the usually considered islanded, or Vollmer-Weber, growth. Using this model, we explain the observed transition from superparamagnetism to ferromagnetism for Fe coverages above 3 monolayers (ML). However, even though ferromagnetism and magnetocrystalline anisotropy are observed for 4 ML, complete coverage of the MgO substrate by the Fe ultrathin films only occurs around 6 ML as determined by polar Kerr spectra and simulations that consider different coverage situations. In annealed 3.5 ML Fe films, shape or configurational anisotropy dominates the intrinsic magnetocrystalline anisotropy, due to an annealing induced continuous to islanded morphological transition. A small interface anisotropy in thicker films is observed, probably due to dislocations observed at the Fe/MgO(001) interface. C1 CSIC, CNM, IMM, Madrid 28760, Spain. Univ Autonoma Barcelona, Inst Ciencia Mat Barcelona, CSIC, Bellaterra, Spain. Univ Paris 11, Inst Elect Fondamentale, F-91405 Orsay, France. Univ Barcelona, EME Elect Mat & Engn, Dept Elect, Barcelona 08028, Spain. Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RP Boubeta, CM (reprint author), CSIC, CNM, IMM, Isaac Newton 8-PTM, Madrid 28760, Spain. EM alfonso@imm.cnm.csic.es RI Garcia-Martin, Jose Miguel/H-4434-2011; armelles, gaspar/K-5375-2012; Microelectronica de Madrid, Instituto de/D-5173-2013; Clavero, Cesar/C-4391-2008; Martinez Boubeta, Carlos/G-9298-2014; Cebollada, Alfonso/B-6754-2012; Balcells, Lluis/B-5027-2013; Peiro, Francesca/N-4436-2014; OI Calveras, Cornet/0000-0002-8537-361X; Garcia-Martin, Jose Miguel/0000-0002-5908-8428; armelles, gaspar/0000-0002-2563-1621; Microelectronica de Madrid, Instituto de/0000-0003-4211-9045; Clavero, Cesar/0000-0001-6665-3141; Martinez Boubeta, Carlos/0000-0001-7665-0649; Cebollada, Alfonso/0000-0003-1990-4520; Balcells, Lluis/0000-0001-6603-7357; Peiro, Francesca/0000-0002-5697-0554; Menendez, Jose Luis/0000-0002-6933-4063 NR 45 TC 32 Z9 32 U1 4 U2 15 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014407 DI 10.1103/PhysRevB.71.014407 PG 10 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100087 ER PT J AU Bud'ko, SL Canfield, PC AF Bud'ko, SL Canfield, PC TI Tuning the Hall coefficient in single crystals of the heavy fermion compound YbNi2B2C by annealing SO PHYSICAL REVIEW B LA English DT Article ID SYSTEMS; SUPERCONDUCTORS; BOROCARBIDES; TRANSPORT; LUNI2B2C; BEHAVIOR AB We present temperature-dependent magnetotransport measurements on as-grown and annealed YbNi2B2C single crystals. Annealing causes drastic changes in the Hall coefficient, R-H(T). Whereas for as-grown samples the Hall coefficient is negative between room temperature and 2 K, with a pronounced minimum at approximate to22 K, for the samples annealed at 950 degreesC for 150 h, R-H(T) changes its sign twice in the same temperature range: from negative to positive on cooling below similar to100 K and back to negative below similar to10 K, and has a clear maximum at approximate to45 K. Intermediate temperature dependencies can be achieved by reducing the annealing time. These findings are discussed within the framework of an annealing dependence of the skew scattering in conjunction with the recent structural, thermodynamic and transport studies of the effects of annealing in YbNi2B2C. C1 Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Bud'ko, SL (reprint author), Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 25 TC 5 Z9 5 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 024409 DI 10.1103/PhysRevB.71.024409 PG 6 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400056 ER PT J AU Cartoixa, X Ting, DZY Chang, YC AF Cartoixa, X Ting, DZY Chang, YC TI Suppression of the D'yakonov-Perel' spin-relaxation mechanism for all spin components in [111]zincblende quantum wells SO PHYSICAL REVIEW B LA English DT Article ID SEMICONDUCTORS; HETEROSTRUCTURES; TRANSISTOR; ANISOTROPY; ELECTRONS AB We apply the D'yakonov-Perel' (DP) formalism to [111]-grown zinc blende quantum wells (QW's) to compute the spin lifetimes of electrons in the two-dimensional electron gas. We account for both bulk and structural inversion asymmetry (Rashba) effects. We see that, under certain conditions, the spin splitting vanishes to first order in k, which effectively suppresses the DP spin relaxation mechanism for all three spin components. We predict extended spin lifetimes as a result, giving rise to the possibility of enhanced spin storage. We also study [110]-grown QW's, where the effect of structural inversion asymmetry is to augment the spin relaxation rate of the component perpendicular to the well. We derive analytical expressions for the spin lifetime tensor and its proper axes, and see that they are dependent on the relative magnitude of the BIA- and SIA-induced splittings. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Cartoixa, X (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. EM XCartoixa-Soler@lbl.gov RI Chang, Yia-Chung/F-4239-2011 NR 31 TC 56 Z9 57 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045313 DI 10.1103/PhysRevB.71.045313 PG 5 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200079 ER PT J AU Castro-Colin, M Donner, W Moss, SC Islam, Z Sinha, SK Nemanich, R Metzger, HT Bosecke, P Shulli, T AF Castro-Colin, M Donner, W Moss, SC Islam, Z Sinha, SK Nemanich, R Metzger, HT Bosecke, P Shulli, T TI Synchrotron x-ray studies of vitreous SiO2 over Si(001). I. Anisotropic glass contribution SO PHYSICAL REVIEW B LA English DT Article ID BOND-ANGLE DISTRIBUTION; SUPERCOOLED LIQUIDS; NEUTRON-SCATTERING; THERMAL-EXPANSION; DIFFRACTION PEAK; SILICA; NETWORK; TRANSITION; TEMPERATURE; INTERFACES AB While numerous investigations of the structure and interface of amorphous SiO2 thermally grown on Si, theoretical as well as experimental, have been carried out over the years, a definitive picture of this thin gate oxide and its interface remains lacking. We have explored this issue using synchrotron x rays in grazing incidence geometry. In this geometry a fourfold modulation in the first sharp diffraction peak (FSDP) from thin vitreous SiO2 of 100 and 500 A thickness can be observed. While the FSDP exhibits a modulation throughout the entire film, this modulation decays away from the interface. Reflectivity measurements were also performed, which reveal an interfacial layer of 3% density increase in the SiO2 film over the bulk (film) density. C1 Univ Houston, Dept Phys, Houston, TX 77204 USA. Univ Houston, Texas Ctr Superconduct & Adv Mat, Houston, TX 77204 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. European Synchrotron Radiat Facil, F-38043 Grenoble 9, France. RP Castro-Colin, M (reprint author), Univ Houston, Dept Phys, Houston, TX 77204 USA. OI Donner, Wolfgang/0000-0001-9269-4473 NR 52 TC 6 Z9 6 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045310 DI 10.1103/PhysRevB.71.045310 PG 7 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200076 ER PT J AU Castro-Colin, M Donner, W Moss, SC Islam, Z Sinha, SK Nemanich, R AF Castro-Colin, M Donner, W Moss, SC Islam, Z Sinha, SK Nemanich, R TI Synchrotron x-ray studies of vitreous SiO2 over Si(001). II. Crystalline contribution SO PHYSICAL REVIEW B LA English DT Article ID THERMALLY GROWN SIO2; INTERFACE; DIFFRACTION; OXIDE; SILICON; SI(100); SURFACE; SCATTERING; MECHANISM; FILMS AB Thermally oxidized thin films grown on Si(001) were analyzed with synchrotron x rays. By looking at crystal truncation rod (CTR) profiles we were able to observe, as have others, a crystalline peak, nominally along the (1 1 L) rod, together with Laue oscillations matching the film thickness. These oscillations are evidence of a crystalline component present throughout the entire film that vanishes away from the interface with the silicon substrate. A model consisting of distorted coesite is proposed to explain the results. C1 Univ Houston, Dept Phys, Houston, TX 77204 USA. Univ Houston, Texas Ctr Superconduct & Adv Mat, Houston, TX 77204 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. RP Castro-Colin, M (reprint author), Univ Houston, Dept Phys, Houston, TX 77204 USA. NR 32 TC 10 Z9 10 U1 2 U2 9 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045311 DI 10.1103/PhysRevB.71.045311 PG 7 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200077 ER PT J AU Chapman, BD Stern, EA Han, SW Cross, JO Seidler, GT Gavrilyatchenko, V Vedrinskii, RV Kraizman, VL AF Chapman, BD Stern, EA Han, SW Cross, JO Seidler, GT Gavrilyatchenko, V Vedrinskii, RV Kraizman, VL TI Diffuse x-ray scattering in perovskite ferroelectrics SO PHYSICAL REVIEW B LA English DT Article ID PHASE-TRANSITIONS; CRYSTAL STABILITY; PHONON-DISPERSION; LOCAL-STRUCTURE; DISORDER; BATIO3; PBTIO3; KNBO3; ANHARMONICITY; MODES AB Diffuse x-ray scattering measurements on the cubic paraelectric phase of single-crystal PbTiO3 are presented. No diffuse scattering sheets are found, in contrast to sheets observed in the cubic paraelectric phases of BaTiO3 and KNbO3. A quantitative analysis of the diffuse scattering indicates that the soft-mode branch contribution to sheets is negligible in all three ferroelectric perovskites. Differences in the diffuse scattering are explained by differences in the disordering of the local displacements, thus resolving a long-standing controversy. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Argonne Natl Lab, Adv Photon Source, Sector 20, PNC,CAT, Argonne, IL 60439 USA. Rostov State Univ, Dept Phys, Rostov Na Donu 344090, Russia. RP Stern, EA (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. EM stern@phys.washington.edu RI Seidler, Gerald/I-6974-2012 NR 30 TC 26 Z9 26 U1 4 U2 14 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 020102 DI 10.1103/PhysRevB.71.020102 PG 4 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400002 ER PT J AU Correa, AA Reboredo, FA Balseiro, CA AF Correa, AA Reboredo, FA Balseiro, CA TI Quantum corral wave-function engineering SO PHYSICAL REVIEW B LA English DT Article ID SCATTERING-THEORY; MIRAGES; COMPUTATION; SURFACE AB We present a theoretical method for the design and optimization of quantum corrals with specific electronic properties. Taking advantage that spins are subject to a Ruderman-Kittel-Kasuya-Yosida interaction that is directly controlled by the scattering of the quantum corral, we design corral structures that reproduce spin Hamiltonians with coupling constants determined a priori. We solve exactly the two-dimensional electron gas scattering problem for each corral configuration within the effective mass approximation and s-wave scattering using a Green function method. Subsequently, the geometry of the quantum corral is optimized with an algorithm that combines simulated annealing and genetic approaches. We demonstrate that it is possible to automatically design quantum corrals with complicated target electronic properties, such as multiple mirages with predefined relative intensities at specific locations. In addition we design structures that are particularly sensitive to the phase shift of impurities at certain positions allowing the measurement of the value of this parameter on the copper surface. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Ctr Atom Bariloche, Inst Balseiro, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina. RP Correa, AA (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM correaa@socrates.berkeley.edu; reboredo1@llnl.gov RI Reboredo, Fernando/B-8391-2009 NR 33 TC 9 Z9 9 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 3 AR 035418 DI 10.1103/PhysRevB.71.035418 PG 9 WC Physics, Condensed Matter SC Physics GA 893RC UT WOS:000226735900135 ER PT J AU Deo, CS Srolovitz, DJ Cai, W Bulatov, VV AF Deo, CS Srolovitz, DJ Cai, W Bulatov, VV TI Kinetic Monte Carlo method for dislocation migration in the presence of solute SO PHYSICAL REVIEW B LA English DT Article ID LOW-TEMPERATURE DEFORMATION; BCC TRANSITION-METALS; CENTRED CUBIC METALS; SCREW DISLOCATIONS; SINGLE-CRYSTALS; MOLECULAR-DYNAMICS; ATOMISTIC SIMULATIONS; VELOCITY MEASUREMENTS; FLOW STRESS; IRON ALLOYS AB We present a kinetic Monte Carlo method for simulating dislocation motion in alloys within the framework of the kink model. The model considers the glide of a dislocation in a static, three-dimensional solute atom atmosphere. It includes both a description of the short-range interaction between a dislocation core and the solute and long-range solute-dislocation interactions arising from the interplay of the solute misfit and the dislocation stress field. Double-kink nucleation rates are calculated using a first-passage-time analysis that accounts for the subcritical annihilation of embryonic double kinks as well as the presence of solutes. We explicitly consider the case of the motion of a <111>-oriented screw dislocation on a {011}-slip plane in body-centered-cubic Mo-based alloys. Simulations yield dislocation velocity as a function of stress, temperature, and solute concentration. The dislocation velocity results are shown to be consistent with existing experimental data and, in some cases, analytical models. Application of this model depends upon the validity of the kink model and the availability of fundamental properties (i.e., single-kink energy, Peierls stress, secondary Peierls barrier to kink migration, single-kink mobility, solute-kink interaction energies, solute misfit), which can be obtained from first-principles calculations and/or molecular-dynamics simulations. C1 Princeton Univ, Princeton Mat Inst, Princeton, NJ 08540 USA. Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48105 USA. Princeton Univ, Dept Mech & Aerosp Engn, Princeton, NJ 08544 USA. Princeton Univ, Princeton Mat Inst, Princeton, NJ 08544 USA. Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RP Princeton Univ, Princeton Mat Inst, Princeton, NJ 08540 USA. NR 52 TC 1 Z9 1 U1 2 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014106 DI 10.1103/PhysRevB.71.014106 PG 12 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100049 ER PT J AU El Shawish, S Bonca, J Batista, CD Sega, I AF El Shawish, S Bonca, J Batista, CD Sega, I TI Electron spin resonance of SrCu2(BO3)(2) at high magnetic fields SO PHYSICAL REVIEW B LA English DT Article ID X-BAND ESR; SYSTEM SRCU2(BO3)(2); GROUND-STATE; TEMPERATURE AB We calculate the electron spin resonance (ESR) spectra of the quasi-two-dimensional dimer spin liquid SrCu2(BO3)(2) as a function of magnetic field B. Using the standard Lanczos method, we solve a Shastry-Sutherland Hamiltonian with additional Dzyaloshinsky-Moriya (DM) terms which are crucial to explain different qualitative aspects of the ESR spectra. In particular, a nearest-neighbor DM interaction with a nonzero D-z component is required to explain the low frequency ESR lines for Bparallel toc. This suggests that crystal symmetry is lowered at low temperatures due to a structural phase transition. C1 Jozef Stefan Inst, SI-1000 Ljubljana, Slovenia. Univ Ljubljana, Fac Math & Phys, SI-1000 Ljubljana, Slovenia. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP El Shawish, S (reprint author), Jozef Stefan Inst, SI-1000 Ljubljana, Slovenia. NR 18 TC 7 Z9 7 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014413 DI 10.1103/PhysRevB.71.014413 PG 5 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100093 ER PT J AU FitzGerald, SA Hannachi, R Sethna, D Rinkoski, M Sieber, KK Sholl, DS AF FitzGerald, SA Hannachi, R Sethna, D Rinkoski, M Sieber, KK Sholl, DS TI Kinetics of H-2 desorption from crystalline C-60 SO PHYSICAL REVIEW B LA English DT Article ID MONTE-CARLO SIMULATIONS; WALLED CARBON NANOTUBES; NE-INTERCALATED C-60; TRANSPORT-DIFFUSIVITIES; SOLID C-60; DIFFUSION; SILICALITE; ZEOLITES; DYNAMICS; HYDROGEN AB The nonequilibrium diffusion of H-2 within crystalline C-60 is examined by monitoring the outgassing of H-2 from C-60 powders. Results show that the desorption-lifetime decreases dramatically with increasing H-2 concentration. Kinetic Monte Carlo simulations indicate that diffusion occurs by H-2 molecules hopping between interstitial octahedral sites via an energetically unstable intermediary tetrahedral site. This diffusion is greatly enhanced by the presence of dimers in which two H-2 molecules briefly occupy the same octahedral site. The abundance of dimers increases with H-2 concentration and leads to simulated desorption curves that are in good agreement with the experimental outgassing data. C1 Oberlin Coll, Dept Phys, Oberlin, OH 44074 USA. Carnegie Mellon Univ, Dept Chem Engn, Pittsburgh, PA 15213 USA. Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. RP FitzGerald, SA (reprint author), Oberlin Coll, Dept Phys, Oberlin, OH 44074 USA. NR 27 TC 9 Z9 9 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045415 DI 10.1103/PhysRevB.71.045415 PG 6 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200122 ER PT J AU Gorelik, LY Kulinich, SI Shekhter, RI Jonson, M Vinokur, VM AF Gorelik, LY Kulinich, SI Shekhter, RI Jonson, M Vinokur, VM TI Mechanically assisted spin-dependent transport of electrons SO PHYSICAL REVIEW B LA English DT Article ID COULOMB-BLOCKADE; MAGNETORESISTANCE; JUNCTIONS AB Spin-dependent tunneling of electrons through magnetic nanostructures containing a mechanically movable quantum dot is considered. It is shown that the mechanically assisted current can be made strongly sensitive to an external magnetic field, leading to a giant magnetotransmittance effect for weak external fields of order 1-10 Oe. C1 Chalmers Univ Technol, Dept Appl Phys, SE-41296 Gothenburg, Sweden. Univ Gothenburg, SE-41296 Gothenburg, Sweden. BI Verkin Inst Low Temp Phys & Engn, UA-61103 Kharkov, Ukraine. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Gorelik, LY (reprint author), Chalmers Univ Technol, Dept Appl Phys, SE-41296 Gothenburg, Sweden. EM gorelik@fy.chalmers.se RI Jonson, Mats/D-6545-2011 NR 18 TC 9 Z9 10 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 3 AR 035327 DI 10.1103/PhysRevB.71.035327 PG 6 WC Physics, Condensed Matter SC Physics GA 893RC UT WOS:000226735900094 ER PT J AU Gracia, L Calatayud, M Andres, J Minot, C Salmeron, M AF Gracia, L Calatayud, M Andres, J Minot, C Salmeron, M TI Migration of the subsurface C impurity in Pd(111) SO PHYSICAL REVIEW B LA English DT Article ID 1ST-PRINCIPLES; TRANSITION; SURFACES; ENERGY AB The diffusion of subsurface impurities such as C in palladium surfaces of (111) orientation has been studied under the generalized gradient approximation combining a pseudopotential plane wave scheme as implemented in the VASP code with the aim of providing a better understanding between theoretical and experimental behavior. We analyze the stability of different subsurface sites, the energy barriers separating them from neighboring sites and the corresponding energy profiles. It is found that the most stable sites are located between the first and second surface layers, in good agreement with the experiments. C1 Univ Paris 06, Chim Theor Lab, F-75252 Paris 05, France. Univ Jaume 1, Dept Ciencies Expt, Castello 12080, Spain. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Minot, C (reprint author), Univ Paris 06, Chim Theor Lab, 4 Pl Jussieu Case 137, F-75252 Paris 05, France. EM minot@lct.jussieu.fr RI Gracia, Lourdes/A-7978-2013; Calatayud, Monica/C-8308-2013; Andres, Juan/A-4112-2008 OI Gracia, Lourdes/0000-0001-9684-2568; Calatayud, Monica/0000-0003-0555-8938; Andres, Juan/0000-0003-0232-3957 NR 13 TC 29 Z9 29 U1 2 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 3 AR 033407 DI 10.1103/PhysRevB.71.033407 PG 4 WC Physics, Condensed Matter SC Physics GA 893RC UT WOS:000226735900028 ER PT J AU Graf, D Choi, ES Brooks, JS Harrison, N Murata, K Konoike, T Mousdis, GA Papavassiliou, GC AF Graf, D Choi, ES Brooks, JS Harrison, N Murata, K Konoike, T Mousdis, GA Papavassiliou, GC TI Magnetization, thermoelectric, and pressure studies of the magnetic-field-induced metal-insulator transition in tau-phase organic conductors SO PHYSICAL REVIEW B LA English DT Article ID PHYSICAL-PROPERTIES; TRANSPORT-PROPERTIES; CRYSTAL; SALTS AB We have investigated the magnetic-field-induced metal-insulator transition in the tau-phase organic conductors, which occurs in fields above 35 T and below 14 K, by magnetization, thermoelectric, and pressure-dependent transport methods. Our results show that the transition is a bulk thermodynamic process where a magnetic-field-dependent gap opens upon entry into the insulating state. We argue that the transition involves a magnetic-field-induced change in the electronic structure. C1 Florida State Univ, NHMFL Phys, Tallahassee, FL 32310 USA. Los Alamos Natl Lab, NHMFL, Los Alamos, NM 87545 USA. Osaka City Univ, Grad Sch Sci, Sumiyoshi Ku, Osaka 5588585, Japan. Natl Inst Mat Sci, Nanomat Lab, Tsukuba, Ibaraki 3050003, Japan. Natl Hellen Res Fdn, Inst Theoret & Phys Chem, GR-11635 Athens, Greece. RP Graf, D (reprint author), Florida State Univ, NHMFL Phys, Tallahassee, FL 32310 USA. RI nhrf, tpci/M-8699-2013; Mousdis, George/G-5573-2011 OI Mousdis, George/0000-0002-0560-4829 NR 29 TC 5 Z9 5 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045117 DI 10.1103/PhysRevB.71.045117 PG 8 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200038 ER PT J AU Hsueh, CH Becher, PF AF Hsueh, CH Becher, PF TI Effects of dopant segregation on lattice-diffusional creep of nanocrystalline ceramics SO PHYSICAL REVIEW B LA English DT Article ID STABILIZED TETRAGONAL ZIRCONIA; GRAIN-BOUNDARY; SPACE-CHARGE; TEMPERATURE DEFORMATION; POLYCRYSTALS; ALUMINA AB The segregation of dopants whose electric charge is different from that of the parent ions and the formation of a space-charge layer induce a local electric field in the grain-boundary region. Depending upon the valence and local electrostatic potential, the charge carriers controlling diffusional creep can be either accumulated or depleted in this space-charge layer, and the creep rate is enhanced or diminished accordingly. A model was recently developed to examine the effects of a segregation-induced local electric field on the lattice-diffusional creep of nanocrystalline ceramics for spherical grains. However, in order to obtain closed-form solutions, the grain size was assumed to be much greater than the width of the space-charge layer in the existing analysis. This assumption can become inappropriate for nanocrystalline materials as the grain size is reduced; thus, a numerical method is used in the present study to resolve the existing equations without that assumption. Using yttria tetragonal zirconia as an example, the difference between the existing approximate closed-form solutions and the present numerical results is shown to be significant when the grain size is less than 50 nm. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Hsueh, Chun-Hway/G-1345-2011 NR 22 TC 1 Z9 1 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014115 DI 10.1103/PhysRevB.71.014115 PG 7 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100058 ER PT J AU Kamakoti, P Sholl, DS AF Kamakoti, P Sholl, DS TI Ab initio lattice-gas modeling of interstitial hydrogen diffusion in CuPd alloys SO PHYSICAL REVIEW B LA English DT Article ID METAL-ALLOYS; PALLADIUM; MEMBRANES; PD; SEPARATION; DISORDER; SINGLE; ORDER; AG; NI AB A comprehensive lattice-gas model has been developed to predict the diffusivities of dilute H in a wide range of structurally disordered fcc CuPd alloys with compositions greater than 47 at. % Pd. We used density functional theory to perform detailed calculations of H binding energies, vibrational frequencies, and activation barriers to local diffusion in two representative alloys having 52 and 74 at. % Pd. These data are used to parametrize all possible hopping rates between adjacent interstitial sites in a lattice model for the entire range of compositions. Kinetic Monte Carlo (KMC) simulations of this lattice model were used to calculate H tracer diffusivities as a function of alloy composition and temperatures ranging from 400 K to 1200 K. The results from these simulations are found to be in good agreement with available experimental data. We have also used KMC simulations to investigate the impact of short-range order on H diffusion in fcc CuPd alloys. The effects of short-range order are found to be small under the conditions of experimental interest. C1 Carnegie Mellon Univ, Dept Chem Engn, Pittsburgh, PA 15213 USA. Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. RP Sholl, DS (reprint author), Carnegie Mellon Univ, Dept Chem Engn, Pittsburgh, PA 15213 USA. EM sholl@andrew.cmu.edu NR 36 TC 56 Z9 57 U1 4 U2 23 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014301 DI 10.1103/PhysRevB.71.014301 PG 9 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100075 ER PT J AU Kaminski, A Fretwell, HM Norman, MR Randeria, M Rosenkranz, S Chatterjee, U Campuzano, JC Mesot, J Sato, T Takahashi, T Terashima, T Takano, M Kadowaki, K Li, ZZ Raffy, H AF Kaminski, A Fretwell, HM Norman, MR Randeria, M Rosenkranz, S Chatterjee, U Campuzano, JC Mesot, J Sato, T Takahashi, T Terashima, T Takano, M Kadowaki, K Li, ZZ Raffy, H TI Momentum anisotropy of the scattering rate in cuprate superconductors SO PHYSICAL REVIEW B LA English DT Article ID RESOLVED PHOTOEMISSION-SPECTROSCOPY; HIGH-TEMPERATURE SUPERCONDUCTORS; T-C SUPERCONDUCTORS; NORMAL-STATE; GAP ANISOTROPY; OVERDOPED BI2SR2CACU2O8+DELTA; ELECTRONIC-STRUCTURE; FERMI-SURFACE; LINE-SHAPE; DISPERSION AB We examine the momentum and energy dependence of the scattering rate of the high-temperature cuprate superconductors using angle-resolved photoemission spectroscopy. The scattering rate is of the form a+bw around the Fermi surface for under-and optimal doping. The inelastic coefficient b is found to be isotropic. The elastic term a, however, is found to be highly anisotropic for under-and optimally doped samples, with an anisotropy which correlates with that of the pseudogap. This is contrasted with heavily overdoped samples, which show an isotropic scattering rate and an absence of the pseudogap above T-c. We find this to be a generic property for both single-and double-layer compounds. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Coll Swansea, Dept Phys, Swansea SA2 8PP, W Glam, Wales. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. ETH, Neutron Scattering Lab, CH-5232 Villigen, Switzerland. PSI Villigen, CH-5232 Villigen, Switzerland. Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. Kyoto Univ, Inst Chem Res, Uji, Kyoto 6110011, Japan. Univ Tsukuba, Inst Mat Sci, Tsukuba 3053573, Japan. Univ Paris 11, Phys Solides Lab, F-91405 Orsay, France. RP Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RI Takahashi, Takashi/E-5080-2010; Sato, Takafumi/E-5094-2010; Tohoku, Arpes/A-4890-2010; Rosenkranz, Stephan/E-4672-2011; Norman, Michael/C-3644-2013 OI Rosenkranz, Stephan/0000-0002-5659-0383; NR 27 TC 64 Z9 64 U1 4 U2 13 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014517 DI 10.1103/PhysRevB.71.014517 PG 7 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100143 ER PT J AU Kayali, MA Kogan, VG Pokrovsky, VL AF Kayali, MA Kogan, VG Pokrovsky, VL TI Dissipation and coherent effects in narrow superconducting channels SO PHYSICAL REVIEW B LA English DT Article AB We apply the time-dependent Ginzburg-Landau (TDGL) equations to study small ac currents of frequency omega in superconducting channels narrow on the scale of London penetration depth. We show that TDGL equations have t-dependent and spatially uniform solutions that describe the order parameter with an oscillating part of the double frequency coexisting with an ac electric field. We evaluate the Ohmic losses (related neither to the flux flow nor to the phase slips) and show that the resistivity reduction on cooling through the critical temperature T-c should behave as (T-c-T)(2)/omega(2). If the channel is cut out of an anisotropic material in a direction other than the principal axes, the transverse phase difference and the Josephson voltage between the channel sides are generated. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. LD Landau Theoret Phys Inst, Moscow 142432, Russia. US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. Baylor Coll Med, Human Neuroimaging Lab, Houston, TX 77030 USA. RP Kayali, MA (reprint author), Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 024525 DI 10.1103/PhysRevB.71.024525 PG 5 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400108 ER PT J AU Kortright, JB Hellwig, O Chesnel, K Sun, SH Fullerton, EE AF Kortright, JB Hellwig, O Chesnel, K Sun, SH Fullerton, EE TI Interparticle magnetic correlations in dense Co nanoparticle assemblies SO PHYSICAL REVIEW B LA English DT Article ID PARTICLE SYSTEM; COBALT; SUPERLATTICES; DYNAMICS; IRON; FE AB Resonant magnetic x-ray scattering from dense assemblies of 9-nm-diameter epsilon-Co and hcp-Co superparamagnetic particles is reported. For lower anisotropy epsilon-Co assemblies remanent scattering is significantly enhanced compared to a random orientation model, indicating that preferred intermoment orientations with antiferromagnetic character exist with spatial frequencies ranging over several nearest neighbors. This interaction-mediated collective behavior is consistent with dipolar energies and exists well into the superparamagnetic regime, revealing that such thermally activated motion is highly correlated. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Hitachi Global Storage Technol, San Jose Res Ctr, San Jose, CA 95120 USA. IBM Corp, Thomas J Watson Res Ctr, Yorktown Hts, NY 10598 USA. RP Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 22 TC 24 Z9 24 U1 0 U2 14 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 012402 DI 10.1103/PhysRevB.71.012402 PG 4 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100012 ER PT J AU Kurtulus, Y Dronskowski, R Samolyuk, GD Antropov, VP AF Kurtulus, Y Dronskowski, R Samolyuk, GD Antropov, VP TI Electronic structure and magnetic exchange coupling in ferromagnetic full Heusler alloys SO PHYSICAL REVIEW B LA English DT Article ID SPIN-WAVES; MAGNETORESISTANCE; SEARCH; FILMS; SI AB Density-functional studies of the electronic structures and exchange interaction parameters have been performed for a series of ferromagnetic full Heusler alloys of general formula Co(2)MnZ (Z=Ga,Si,Ge,Sn), Rh(2)MnZ (Z=Ge,Sn,Pb), Ni2MnSn, Cu2MnSn, and Pd2MnSn, and the connection between the electronic spectra and the magnetic interactions have been studied. Different mechanisms contributing to the exchange coupling are revealed. The band dependence of the exchange parameters, their dependence on volume and valence electron concentration have been thoroughly analyzed within the Green function technique. The difference between the exact adiabatic approach and the long-wavelength approximation is discussed. C1 Rhein Westfal TH Aachen, Inst Anorgan Chem, D-52056 Aachen, Germany. Ames Lab, Ames, IA 50011 USA. RP Kurtulus, Y (reprint author), Rhein Westfal TH Aachen, Inst Anorgan Chem, D-52056 Aachen, Germany. NR 34 TC 100 Z9 101 U1 0 U2 23 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014425 DI 10.1103/PhysRevB.71.014425 PG 12 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100105 ER PT J AU Larochelle, S Mehta, A Lu, L Mang, PK Vajk, OP Kaneko, N Lynn, JW Zhou, L Greven, M AF Larochelle, S Mehta, A Lu, L Mang, PK Vajk, OP Kaneko, N Lynn, JW Zhou, L Greven, M TI Structural and magnetic properties of the single-layer manganese oxide La1-xSr1+xMnO4 SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-SCATTERING; CHARGE-ORDERED STRIPES; 2-DIMENSIONAL ANTIFERROMAGNETS; MAGNETORESISTIVE MANGANITE; HEISENBERG-ANTIFERROMAGNET; PHASE-SEPARATION; METAL TRANSITION; WIGNER-CRYSTAL; BI-STRIPE; LA0.5SR1.5MNO4 AB Using x-ray and neutron scattering, we have studied the structural and magnetic properties of the single-layer manganite La1-xSr1+xMnO4(0less than or equal tox<0.7). Single crystals were grown by the floating-zone method at 18 La/Sr concentrations. The low-temperature phase diagram can be understood by considering the strong coupling of the magnetic and orbital degrees of freedom, and it can be divided into three distinct regions: low (x<0.12), intermediate (0.12less than or equal tox<0.45), and high (xgreater than or equal to0.45) doping. LaSrMnO4(x=0) is an antiferromagnetic Mott insulator, and its spin-wave spectrum is well described by linear spin-wave theory for the spin-2 square-lattice Heisenberg Hamiltonian with Ising anisotropy. Upon doping, as the e(g) electron concentration (1-x) decreases, both the two-dimensional antiferromagnetic spin correlations in the paramagnetic phase and the low-temperature ordered moment decrease due to an increase of frustrating interactions, and Neel order disappears above x(c)=0.115(10). The magnetic frustration is closely related to changes in the e(g) orbital occupancies and the associated Jahn-Teller distortions. In the intermediate region, there exists neither long-range magnetic nor superstructural order. Short-range-correlated structural "nanopatches" begin to form above xsimilar to0.25. At high doping (xgreater than or equal to0.45), the ground state of La1-xSr1+xMnO4 exhibits long-range superstructural order and a complex antiferromagnetic order, which differs from that at low doping. The superstructural order is thought to arise from charge and orbital ordering on the Mn sites, and for x=0.50 we conclude that it is of B2mm symmetry. For x>0.50, the superstructural order becomes incommensurate with the lattice, with a modulation wave vector epsilon that depends linearly on the e(g) electron concentration: epsilon=2(1-x). On the other hand, the magnetic order remains commensurate, but loses its long-range coherence upon doping beyond x=0.50. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Larochelle, S (reprint author), Univ Toronto, Dept Phys, 60 St George St, Toronto, ON M5S 1A7, Canada. NR 85 TC 77 Z9 77 U1 3 U2 26 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 024435 DI 10.1103/PhysRevB.71.024435 PG 18 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400082 ER PT J AU Lawes, G Risbud, AS Ramirez, AP Seshadri, R AF Lawes, G Risbud, AS Ramirez, AP Seshadri, R TI Absence of ferromagnetism in Co and Mn substituted polycrystalline ZnO SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC SEMICONDUCTORS; ROOM-TEMPERATURE; SPIN INJECTION; THIN-FILMS; DOPED ZNO; SUSCEPTIBILITY; INTERFACE AB We discuss the properties of semiconducting bulk ZnO when substituted with the magnetic transition metal ions Mn and Co, with substituent fraction ranging from x=0.02 to x=0.15. The magnetic properties were measured as a function of magnetic field and temperature and we find no evidence for magnetic ordering in these systems down to T=2 K. The magnetization can be fit by the sum of a Curie-Weiss term with a Weiss temperature of Theta>100 K and a Curie term. We attribute this behavior to contributions from both tM ions with tM nearest neighbors and from isolated spins. This particular functional form for the susceptibility is used to explain why no ordering is observed in tM substituted ZnO samples despite the large values of the Weiss temperature. We also discuss in detail the methods we used to minimize any impurity contributions to the magnetic signal. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM glawes@lanl.gov; aditi@engineering.ucsb.edu; apr@lucent.com; seshadri@mrl.ucsb.edu RI Seshadri, Ram/C-4205-2013 OI Seshadri, Ram/0000-0001-5858-4027 NR 29 TC 373 Z9 389 U1 3 U2 31 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045201 DI 10.1103/PhysRevB.71.045201 PG 5 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200052 ER PT J AU Lee, TW Gray, SK AF Lee, TW Gray, SK TI Controlled spatiotemporal excitation of metal nanoparticles with picosecond optical pulses SO PHYSICAL REVIEW B LA English DT Article ID SURFACE-PLASMONS; COHERENT CONTROL; DYNAMICS; POLARITONS; SCATTERING AB We discuss realistic finite-difference time-domain simulations of chirped optical pulses interacting with silver nanowires and cone-shaped nanoparticles. These systems are differently shaped and larger than those previously studied [M. I. Stockman, S. V. Faleev, and D. J. Bergman, Phys. Rev. Lett. 88, 067402 (2002)], but still allow for localized hot spots near the metal surfaces to be generated and controlled in a spatiotemporal manner. The control is made possible by chirping the pulses such that the effective frequency passes through surface plasmon resonances associated with different spatial regions of the nanostructure over the course of time. We demonstrate how this leads to counterintuitive, negative group velocities in some situations. The control is shown to scale with pulse duration from approximate to150 fs to at least approximate to2200 fs=2.2 ps, and we anticipate it to scale to longer durations. We further show that the response of such nanostructures to chirped pulses can provide a means of encoding or decoding optical signals, which could be verified experimentally. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. RP Lee, TW (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 30 TC 18 Z9 19 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 3 AR 035423 DI 10.1103/PhysRevB.71.035423 PG 9 WC Physics, Condensed Matter SC Physics GA 893RC UT WOS:000226735900140 ER PT J AU Leonard, F Bartelt, NC Kellogg, GL AF Leonard, F Bartelt, NC Kellogg, GL TI Effects of elastic anisotropy on the periodicity and orientation of striped stress domain patterns at solid surfaces SO PHYSICAL REVIEW B LA English DT Article ID KINK FORMATION ENERGIES; STEP; PB(111) AB The length scale of stress domain patterns formed at solid surfaces is usually calculated using isotropic elasticity theory. Because this length depends exponentially on elastic constants, deviations between isotropic and anisotropic elasticity can lead to large errors. Another inaccuracy of isotropic elasticity theory is that it neglects the dependence of elastic relaxations on stripe orientation. To remove these inaccuracies, we calculate the energy of striped domain patterns using anisotropic elasticity theory for an extensive set of surfaces encountered in experimental studies of self-assembly. We present experimental and theoretical evidence that elastic anisotropy is large enough to determine the stripe orientation when Pb is deposited on Cu(111). Our analytical and numerical results should be useful for analysis of a broad range of experimental systems. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Leonard, F (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. RI Bartelt, Norman/G-2927-2012 NR 22 TC 15 Z9 15 U1 1 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045416 DI 10.1103/PhysRevB.71.045416 PG 7 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200123 ER PT J AU Li, ZY Ho, KM AF Li, ZY Ho, KM TI Bloch mode reflection and lasing threshold in semiconductor nanowire laser arrays SO PHYSICAL REVIEW B LA English DT Article ID SUBWAVELENGTH-DIAMETER SILICA; WAVE-GUIDES; WIRES AB We use a plane-wave-based transfer-matrix method to investigate the dispersion and intrinsic reflection coefficients of electromagnetic guided waves at the facets of single isolated semiconductor nanowires and one-dimensional periodic nanowire arrays. The knowledge of such reflection losses can help people to understand the intrinsic threshold of laser operation in these nanowire laser systems. We find that the dispersion of guided modes in a nanowire array is not sensitive to the interwire distance, while the reflection coefficients of Bloch guided modes strongly depend on this interwire distance, and can be much different from that in a single isolated nanowire. The reflection spectrum also differs much for different polarization modes in the nanowire array. We also find that the quantitative features of these complex reflection spectra cannot be adequately explained by only considering the energy flux and field profiles of the guided mode itself that is involved in the reflection. A satisfactory physical model should involve the leaky wave modes supported by the nanowire. The contribution from both the propagating guided modes and decaying leaky modes has been fully described within the framework of the transfer-matrix method. C1 Chinese Acad Sci, Inst Phys, Beijing 100080, Peoples R China. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Li, ZY (reprint author), Chinese Acad Sci, Inst Phys, POB 603, Beijing 100080, Peoples R China. EM lizy@aphy.iphy.ac.cn NR 25 TC 13 Z9 13 U1 1 U2 13 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045315 DI 10.1103/PhysRevB.71.045315 PG 11 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200081 ER PT J AU Lorenz, B Yen, F Gospodinov, MM Chu, CW AF Lorenz, B Yen, F Gospodinov, MM Chu, CW TI Field-induced phases in HoMnO3 at low temperatures SO PHYSICAL REVIEW B LA English DT Article ID POWDER DIFFRACTION DATA; MAGNETIC-STRUCTURE; RMNO3; EVOLUTION AB The field-induced re-entrant phase in multiferroic hexagonal HoMnO3 is investigated to lower temperatures by dc magnetization, ac susceptibility, and specific heat measurements at various magnetic fields. Two new phases have been unambiguously identified below the Neel transition temperature, T-N=76 K, for magnetic fields up to 50 kOe. The existence of an intermediate phase between the P (6) under bar (3)(c) under barm and P (6) under bar (3)c (m) under bar magnetic structures (previously predicted from dielectric measurements) was confirmed and the magnetic properties of this phase have been investigated. At low temperatures (T<5 K) a dome shaped phase boundary characterized by a magnetization jump and a narrow heat capacity peak was detected between the magnetic fields of 5 kOe and 18 kOe. The transition across this phase boundary is of first order and the magnetization and entropy jumps obey the magnetic analogue of the Clausius-Clapeyron relation. Four of the five low-temperature phases coexist at a tetracritical point at 2 K and 18 kOe. The complex magnetic phase diagram so derived provides an informative basis for unraveling the underlying driving forces for the occurrence of the various phases and the coupling between the different orders. C1 Univ Houston, Dept Phys, Houston, TX 77204 USA. Univ Houston, TCSUH, Houston, TX 77204 USA. Bulgarian Acad Sci, Inst Solid State Phys, BU-1784 Sofia, Bulgaria. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Hong Kong Univ Sci & Technol, Hong Kong, Hong Kong, Peoples R China. RP Lorenz, B (reprint author), Univ Houston, Dept Phys, Houston, TX 77204 USA. RI Yen, Fei/C-8713-2015 OI Yen, Fei/0000-0003-2295-3040 NR 13 TC 72 Z9 73 U1 2 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014438 DI 10.1103/PhysRevB.71.014438 PG 9 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100118 ER PT J AU Luo, ZP Miller, DJ Mitchell, JF AF Luo, ZP Miller, DJ Mitchell, JF TI Electron microscopic evidence of charge-ordered bi-stripe structures in the bilayered colossal magnetoresistive manganite La2-2xSr1+2xMn2O7 SO PHYSICAL REVIEW B LA English DT Article ID WIGNER-CRYSTAL; LA0.5CA0.5MNO3; LA1-XCAXMNO3; LASR2MN2O7; PHASE; SPIN AB In sharp contrast to the three-dimensional perovskite manganite, evidence of charge-ordered structures with bi-stripe models has been found on the bilayered manganite La2-2xSr1+2xMn2O7 based on in-situ electron microscopic studies. At the electronic doping level of x=0.6, a new face-centered charge-ordered superstructure was observed. This structure is composed of bi-stripes of Mn3+O6 and paired Mn4+O6 rows alternatively stacking along the ordering direction, which is assembled from the building blocks of the charge-ordered phase at x=0.5. Taking into account the systematic absence of reflections with the face-centered symmetry, its modulation vector was deduced as q=(1/10,1/10,0). Moreover, for another charge-ordered phase identified at x=0.67 with q=(1/6,1/6,0), again only the bi-stripe model fits the existing data over the Wigner-crystal model. C1 Texas A&M Univ, Microscopy & Imaging Ctr, College Stn, TX 77843 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Texas A&M Univ, Microscopy & Imaging Ctr, Biol Sci Bldg W, College Stn, TX 77843 USA. EM luo@mic.tamu.edu RI Luo, Zhiping/C-4435-2014 OI Luo, Zhiping/0000-0002-8264-6424 NR 29 TC 8 Z9 9 U1 1 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014418 DI 10.1103/PhysRevB.71.014418 PG 7 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100098 ER PT J AU Ma, BS Su, FH Ding, K Li, GH Zhang, Y Mascarenhas, A Xin, HP Tu, CW AF Ma, BS Su, FH Ding, K Li, GH Zhang, Y Mascarenhas, A Xin, HP Tu, CW TI Pressure behavior of the alloy band edge and nitrogen-related centers in GaAs0.999N0.001 SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; PAIR LUMINESCENCE; DOPED GAAS; GAP-N; ISOELECTRONIC IMPURITIES; GAAS1-XNX ALLOYS; GAINNAS ALLOYS; PHOTOLUMINESCENCE; CLUSTERS; ENERGY AB The photoluminescence of a GaAsN alloy with 0.1% nitrogen has been studied under pressures up to 8.5 GPa at 33, 70, and 130 K. At ambient pressure, emissions from both the GaAsN alloy conduction band edge and discrete nitrogen-related bound states are observed. Under applied pressure, these two types of emissions shift with rather different pressure coefficients: about 40 meV/GPa for the nitrogen-related features, and about 80 meV/GPa for the alloy band-edge emission. Beyond 1 GPa, these discrete nitrogen-related peaks broaden and evolve into a broad band. Three new photoluminescence bands emerge on the high-energy side of the broad band, when the pressure is above 2.5, 4.5, and 5.25 GPa, respectively, at 33 K. In view of their relative energy positions and pressure behavior, we have attributed these new emissions to the nitrogen-pair states NN3 and NN4, and the isolated nitrogen state N-x. In addition, we have attributed the high-energy component of the broad band formed above 1 GPa to resonant or near-resonant NN1 and NN2, and its main body to deeper cluster centers involving more than two nitrogen atoms. This study reveals the persistence of all the paired and isolated nitrogen-related impurity states, previously observed only in the dilute doping limit, into a rather high doping level. Additionally, we find that the responses of different N-related states to varying N-doping levels differ significantly and in a nontrivial manner. C1 Chinese Acad Sci, Inst Semicond, State Key Lab Superlattices & Microstruct, Beijing 100083, Peoples R China. Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. RP Chinese Acad Sci, Inst Semicond, State Key Lab Superlattices & Microstruct, POB 912, Beijing 100083, Peoples R China. NR 46 TC 14 Z9 16 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045213 DI 10.1103/PhysRevB.71.045213 PG 9 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200064 ER PT J AU Majzoub, EH McCarty, KF Ozolins, V AF Majzoub, EH McCarty, KF Ozolins, V TI Lattice dynamics of NaAlH4 from high-temperature single-crystal Raman scattering and ab initio calculations: Evidence of highly stable AlH4- anions SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-DIFFRACTION; REVERSIBLE HYDROGEN STORAGE; TOTAL-ENERGY CALCULATIONS; SODIUM ALUMINUM HYDRIDES; WAVE BASIS-SET; DOPED NAALH4; MOLECULAR-DYNAMICS; ALANATES; PSEUDOPOTENTIALS; EFFICIENT AB Polarized Raman scattering on single crystals of NaAlH4 has been used to determine the symmetry properties and frequencies of the Raman-active vibrational modes over the temperature range from 300 to 425 K, i.e., up to the melting point T-melt. Significant softening (by up to 6%) is observed in the modes involving rigid translations of Na+ cations and translations and librations of AlH4-. Surprisingly, the data indicate mode softening of less than 1.5% for the Al-H stretching and Al-H bending modes of the AlH4- anion. These results show that the AlH4- anion remains a stable structural entity even near the melting point. First-principles linear response calculations of phonon mode frequencies are in reasonably good agreement with the Raman results. The phonon mode Gruneisen parameters, calculated using the quasiharmonic approximation, are found to be significantly higher for the translational and librational modes than for the Al-H bending and stretching modes, but cannot account quantitatively for the dramatic softening observed near T-melt in the former two types of modes, suggesting an essentially anharmonic mechanism. The effect of zero-point vibrations on the calculated lattice parameters is found to be large (expansion by 1.2 and 1.5 % in the a and c parameters, respectively), as expected for a compound with many light elements. We discuss the implications of the observed mode softening for the kinetics of hydrogen release and hypothesize that breaking up the AlH4- anions is the rate limiting step. The enhanced kinetics of absorption and desorption in Ti-doped NaAlH4 powders is attributed to the effectiveness of Ti in promoting the breakup of the AlH4- anions. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Univ Calif Los Angeles, Dept Mat Sci & Engn, Los Angeles, CA 90095 USA. RP Majzoub, EH (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. RI Ozolins, Vidvuds/D-4578-2009; McCarty, Kevin/F-9368-2012 OI McCarty, Kevin/0000-0002-8601-079X NR 33 TC 62 Z9 63 U1 0 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 024118 DI 10.1103/PhysRevB.71.024118 PG 10 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400034 ER PT J AU Martin, C Agosta, CC Tozer, SW Radovan, HA Palm, EC Murphy, TP Sarrao, JL AF Martin, C Agosta, CC Tozer, SW Radovan, HA Palm, EC Murphy, TP Sarrao, JL TI Evidence for the Fulde-Ferrell-Larkin-Ovchinnikov state in CeCoIn5 from penetration depth measurements SO PHYSICAL REVIEW B LA English DT Article ID ORGANIC SUPERCONDUCTOR; 2D SUPERCONDUCTORS; FIELD AB We report penetration depth and resistivity measurements on the heavy fermion superconductor CeCoIn5 using a self-resonant tank circuit based on a tunnel diode oscillator. For magnetic fields applied near parallel to the ab planes and temperatures below 250 mK, two phase transitions were found. The lower field transition, within the superconducting state, is of a second order and we identify it as the transition from the ordinary vortex state to the Fulde, Ferrell, Larkin, Ovchinnikov (FFLO) state. The higher field transition marks the change from the FFLO to the normal state. This higher field transition, H-c2, is of first order up to 900 mK, the highest temperature measured. Our normal-state resistivity measurements at temperatures between 100 and 900 mK suggest that the FFLO state is related to the change of the quasiparticle interaction strength, F-0(a). C1 Clark Univ, Dept Phys, Worcester, MA 01610 USA. Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Martin, C (reprint author), Clark Univ, Dept Phys, Worcester, MA 01610 USA. EM cagosta@clarku.edu NR 35 TC 62 Z9 62 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 020503 DI 10.1103/PhysRevB.71.020503 PG 4 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400013 ER PT J AU Metzger, WK Ahrenkiel, RK Dashdorj, J Friedman, DJ AF Metzger, WK Ahrenkiel, RK Dashdorj, J Friedman, DJ TI Analysis of charge separation dynamics in a semiconductor junction SO PHYSICAL REVIEW B LA English DT Article ID TRANSIENT PHOTOLUMINESCENCE DECAY; CHEMICAL-VAPOR-DEPOSITION; 2ND-HARMONIC GENERATION; ELECTRIC-FIELDS; GRAIN-BOUNDARY; THIN-FILMS; PHOTOCONDUCTIVITY; TRANSPORT; COMPOSITES; IN0.53GA0.47AS AB Charge separation has been experimentally observed in a number of junction devices over the last decade, but there has been little theoretical analysis of the phenomena that describes the detailed dynamics of the effect. In this work, we use computer simulations to assess the ability of time-resolved photoluminescence, resonant-coupled photoconductive decay, and other experimental techniques to characterize free-carrier recombination and charge separation after an ultrafast laser pulse excites carriers in a homojunction or a heterojunction. The results indicate the experimental conditions where charge separation is likely to dominate these measurements and several experimental signatures that can be used to distinguish charge separation from free-carrier recombination. Time-resolved photoluminescence and resonant-coupled photoconductive decay measurements on Si, GaAs/GaxIn1-xP, and other junctions confirm and illustrate the results. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Metzger, WK (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 42 TC 43 Z9 44 U1 4 U2 25 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 3 AR 035301 DI 10.1103/PhysRevB.71.035301 PG 9 WC Physics, Condensed Matter SC Physics GA 893RC UT WOS:000226735900068 ER PT J AU Morosan, E Bud'ko, SL Canfield, PC AF Morosan, E Bud'ko, SL Canfield, PC TI Angular-dependent planar metamagnetism in the hexagonal compounds TbPtIn and TmAgGe SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC-PROPERTIES; TRANSITIONS; ANISOTROPY; HONI2B2C; TB AB Detailed magnetization measurements M(T,H,theta), were performed on single crystals of TbPtIn and TmAgGe (both members of the hexagonal Fe2P/ZrNiAl structure type) for the magnetic field H applied perpendicular to the crystallographic c axis. These data allowed us to identify, for each compound, the easy axes for the magnetization, which coincided with high symmetry directions ([120] for TbPtIn and [110] for TmAgGe). For fixed orientations of the field along each of the two sixfold symmetry axes, a number of magnetically ordered phases is being revealed by M(H,T) measurements below T-N. Moreover, Tsimilar or equal to2 K, M(H)\(theta) measurements for both compounds (with H applied parallel to the basal plane), as well as T=20 K data for TbPtIn, reveal five metamagnetic transitions with simple angular dependencies H(ci,j)similar to1/cos(theta+/-phi), where phi=0degrees or 60degrees. The high-field magnetization state varies with theta as 2/3mu(sat)(R3+)cos theta, and corresponds to a crystal field limited saturated paramagnetic state. Analysis of these data allowed us to model the angular dependence of the locally saturated magnetizations M-sat and critical fields H-c with a three coplanar Ising-like model, in which the magnetic moments are assumed to be parallel to three adjacent easy axes. Furthermore, net distributions of moments were inferred based on the measured data and the proposed model. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP Morosan, E (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 14 TC 20 Z9 20 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014445 DI 10.1103/PhysRevB.71.014445 PG 20 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100125 ER PT J AU Neaton, JB Ederer, C Waghmare, UV Spaldin, NA Rabe, KM AF Neaton, JB Ederer, C Waghmare, UV Spaldin, NA Rabe, KM TI First-principles study of spontaneous polarization in multiferroic BiFeO3 SO PHYSICAL REVIEW B LA English DT Article ID BRILLOUIN-ZONE INTEGRATIONS; AUGMENTED-WAVE METHOD; THIN-FILMS; FERROELECTRIC POLARIZATION; ELECTRONIC-STRUCTURE; ROOM-TEMPERATURE; CRYSTAL; SPECTRA; METALS; CHARGE AB The ground-state structural and electronic properties of ferroelectric BiFeO3 are calculated using density functional theory within the local spin-density approximation (LSDA) and the LSDA+U method. The crystal structure is computed to be rhombohedral with space group R3c, and the electronic structure is found to be insulating and antiferromagnetic, both in excellent agreement with available experiments. A large ferroelectric polarization of 90-100 muC/cm(2) is predicted, consistent with the large atomic displacements in the ferroelectric phase and with recent experimental reports, but differing by an order of magnitude from early experiments. One possible explanation is that the latter may have suffered from large leakage currents. However, both past and contemporary measurements are shown to be consistent with the modern theory of polarization, suggesting that the range of reported polarizations may instead correspond to distinct switching paths in structural space. Modern measurements on well-characterized bulk samples are required to confirm this interpretation. C1 Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. Jawaharlal Nehru Ctr Adv Sci Res, Bangalore 560064, Karnataka, India. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Mol Foundry, Berkeley, CA 94720 USA. RI Ederer, Claude/F-5420-2010; Spaldin, Nicola/A-1017-2010; Neaton, Jeffrey/F-8578-2015 OI Spaldin, Nicola/0000-0003-0709-9499; Neaton, Jeffrey/0000-0001-7585-6135 NR 47 TC 684 Z9 705 U1 35 U2 306 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 014113 DI 10.1103/PhysRevB.71.014113 PG 8 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100056 ER PT J AU Pan, W Csathy, GA Tsui, DC Pfeiffer, LN West, KW AF Pan, W Csathy, GA Tsui, DC Pfeiffer, LN West, KW TI Transition from a fractional quantum Hall liquid to an electron solid at Landau level filling nu=1/3 in tilted magnetic fields SO PHYSICAL REVIEW B LA English DT Article ID 2-DIMENSIONAL HOLE SYSTEM; SPIN TRANSITION; CYCLOTRON-RESONANCE; GAS; CONDUCTIVITY; ENERGIES; CHARGE; STATES; PHASE; WELLS AB We have observed in a low density two-dimensional hole system (2DHS) of extremely high quality (with hole density p=1.6x10(10) cm(-2) and mobility mu=0.8x10(6) cm(2)/V s) that, as the 2DHS is continuously tilted with respect to the direction of the magnetic field, the nu=1/3 fractional quantum Hall effect (FQHE) state is weakened and at the temperature of similar to30 mK its magnetoresistivity rises from similar to0.4 kOmega/square in the normal orientation to similar to180 kOmega/square at tilt angle thetasimilar to80degrees. We attribute this phenomenon to the transition from the FQHE liquid state to the pinned Wigner solid state, and argue that its origin is the strong coupling of subband Landau levels under the tilted magnetic fields. C1 Princeton Univ, Dept Elect Engn, Princeton, NJ 08544 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07954 USA. RP Pan, W (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. EM wpan@sandia.gov NR 36 TC 3 Z9 3 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 3 AR 035302 DI 10.1103/PhysRevB.71.035302 PG 5 WC Physics, Condensed Matter SC Physics GA 893RC UT WOS:000226735900069 ER PT J AU Peijzel, PS Vergeer, P Meijerink, A Reid, MF Boatner, LA Burdick, GW AF Peijzel, PS Vergeer, P Meijerink, A Reid, MF Boatner, LA Burdick, GW TI 4f(n-1)5d -> 4f(n) emission of Ce3+, Pr3+, Nd3+, Er3+, and Tm3+ in LiYF4 and YPO4 SO PHYSICAL REVIEW B LA English DT Article ID CRYSTAL-FIELD PARAMETRIZATION; LANTHANIDE IONS; OPTICAL-SPECTRA; ENERGY-LEVELS; LUPO4; TRANSITIONS AB High-resolution 4f(n-1)5d-->4f(n) emission spectra in the (vacuum) ultraviolet are reported for Ce3+, Pr3+, Nd3+, Er3+, and Tm3+ in LiYF4 and YPO4 host lattices. The positions and intensities of the zero-phonon lines are calculated and compared to the high-resolution emission spectra. For the thulium samples gated detection has been used to distinguish between the spin-forbidden and spin-allowed 4f(n-1)5d-->4f(n) emissions. Luminescence lifetimes for the spin-forbidden 4f(n-1)5d-->4f(n) emissions are calculated and compared with experimentally observed lifetimes. A good agreement between experiment and theory is found, demonstrating the validity of the model developed for the 4f(n-1)5d and 4f(n) states of lanthanide ions. C1 Univ Utrecht, Debye Inst, NL-3508 TA Utrecht, Netherlands. Univ Canterbury, Dept Phys & Astron, Christchurch 1, New Zealand. Oak Ridge Natl Lab, Condensed Matter Sci Div, Oak Ridge, TN 37831 USA. Andrews Univ, Dept Phys, Berrien Springs, MI 49104 USA. RP Peijzel, PS (reprint author), Univ Utrecht, Debye Inst, POB 80 000, NL-3508 TA Utrecht, Netherlands. EM p.s.peijzel@phys.uu.nl RI Meijerink, Andries/C-4897-2009; Burdick, Gary/D-3233-2013; Institute (DINS), Debye/G-7730-2014; Boatner, Lynn/I-6428-2013 OI Meijerink, Andries/0000-0003-3573-9289; Burdick, Gary/0000-0002-8066-5330; Boatner, Lynn/0000-0002-0235-7594 NR 25 TC 39 Z9 39 U1 2 U2 24 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 4 AR 045116 DI 10.1103/PhysRevB.71.045116 PG 9 WC Physics, Condensed Matter SC Physics GA 893RF UT WOS:000226736200037 ER PT J AU Qian, MC Fong, CY Pickett, WE Pask, JE Yang, LH Dag, S AF Qian, MC Fong, CY Pickett, WE Pask, JE Yang, LH Dag, S TI Spin-polarized ballistic transport in a thin superlattice of zinc blende half-metallic compounds SO PHYSICAL REVIEW B LA English DT Article ID TOTAL-ENERGY CALCULATIONS; MOLECULAR-BEAM EPITAXY; ELECTRON-GAS; PSEUDOPOTENTIALS AB We examine theoretically ballistic conduction in thin layers of zinc blende half metals, considering as an example a superlattice consisting of monolayers of GaAs and MnAs, a bilayer of CrAs, and a bilayer of GaAs. By artificially separating bilayers, we show that surface states thwart half metallicity. However, capping the metal-As bilayers restores half metallicity, and ballistic conduction of electrons within similar to0.3 eV of the Fermi level will give nearly 100% spin-polarized transmission in the direction of the superlattice. Recent developments suggest atomic layer epitaxy can be used to produce such thin layers for spintronic applications. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Div H, Livermore, CA 94551 USA. Bilkent Univ, Dept Phys, TR-06800 Ankara, Turkey. RP Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. EM mqian@physics.ucdavis.edu NR 25 TC 16 Z9 16 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 1 AR 012414 DI 10.1103/PhysRevB.71.012414 PG 4 WC Physics, Condensed Matter SC Physics GA 893QU UT WOS:000226735100024 ER PT J AU Salem-Sugui, S Alvarenga, AD Friesen, M Goretta, KC Schilling, OF Gandra, FG Veal, BW Paulikas, P AF Salem-Sugui, S Alvarenga, AD Friesen, M Goretta, KC Schilling, OF Gandra, FG Veal, BW Paulikas, P TI Vortex dynamics differences due to twin-boundary pinning anisotropy in YBa2Cu3Ox at low temperatures for H parallel to ab planes SO PHYSICAL REVIEW B LA English DT Article ID LOCAL STRUCTURAL VARIATIONS; LIVINGSTON SURFACE-BARRIER; MAGNETIC-FLUX PENETRATION; SINGLE-CRYSTAL; THIN-FILMS; CREEP; SUPERCONDUCTORS; RELAXATION; ENERGY; MOTION AB We measured the magnetization M of a twin-aligned single crystal of YBa2Cu3Ox (YBaCuO), with T-c=91 K, as a function of temperature T and magnetic field H, with H applied along the ab planes. Isothermal M-vs-H and M-vs-time curves were obtained with H applied parallel (parallel to) and perpendicular (perpendicular to) to the twin boundary (TB) direction. M-vs-H curves exhibited two minima below 38 K, which resembled similar curves that have been obtained in YBaCuO for Hparallel toc axis. Above 12 K, the field positions of the minima for Hparallel toTB and Hperpendicular toTB were quite similar. Below 12 K, the position of the second minimum H-min occurred at a higher field value with Hparallel toTB. Below 6 K, only one minimum appeared for both field directions. At low temperatures, these minima in the M-vs-H curves produced maxima in the critical current. It was determined that vortex lines were expelled more easily for Hparallel toTB than for Hperpendicular toTB and, therefore, below a certain field value, that J(c)(Hperpendicular toTB) was larger than J(c)(Hparallel toTB). At T<12 K with Hparallel toTB, the relaxation rate for flux lines leaving the crystal was found to be different from that for flux entering the crystal. We also observed flux jumps at low temperatures, with their sizes depending on the orientation of magnetic field with respect to the TB's. C1 Univ Fed Rio de Janeiro, Inst Fis, BR-21945970 Rio De Janeiro, RJ, Brazil. Ctr Brasileiro Pesquisas Fis, BR-22290180 Rio De Janeiro, Brazil. Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. Argonne Natl Lab, Energy Technol Lab, Argonne, IL 60439 USA. Univ Fed Santa Catarina, Dept Fis, BR-88040900 Florianopolis, SC, Brazil. Univ Estadual Campinas, Inst Fis, BR-13083970 Campinas, SP, Brazil. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Salem-Sugui, S (reprint author), Univ Fed Rio de Janeiro, Inst Fis, C68528, BR-21945970 Rio De Janeiro, RJ, Brazil. RI Alvarenga, Ana Paula/M-9790-2014; Inst. of Physics, Gleb Wataghin/A-9780-2017 NR 34 TC 3 Z9 3 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN PY 2005 VL 71 IS 2 AR 024503 DI 10.1103/PhysRevB.71.024503 PG 7 WC Physics, Condensed Matter SC Physics GA 893QX UT WOS:000226735400086 ER PT J AU Schmeltzer, D Saxena, A Bishop, AR Smith, DL AF Schmeltzer, D Saxena, A Bishop, AR Smith, DL TI Electron transmission through a short interacting wire: 0.7 conductance anomaly SO PHYSICAL REVIEW B LA English DT Article ID QUANTUM POINT CONTACTS; SPIN POLARIZATION; CONDUCTANCE; RENORMALIZATION; MODEL; GAS AB We investigate electron transmission through a short wire with electron-electron interactions which is coupled to noninteracting metallic leads by tunneling matrix elements. We identify two temperature regimes (a) T-Kondo0 the effective (renormalized) electron-electron interaction is larger than the tunneling matrix element. This case is equivalent to a Kondo problem. We find for T3/2(-) ground-state transitions. The rather large energy difference of 150 keV is suggested to arise from Coulomb monopole contributions. Shell-model calculations support this interpretation. C1 Lund Univ, Dept Phys, S-22100 Lund, Sweden. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37830 USA. Keele Univ, Sch Chem & Phys, Keele ST5 5BG, Staffs, England. RP Lund Univ, Dept Phys, S-22100 Lund, Sweden. RI Rudolph, Dirk/D-4259-2009; Ekman, Jorgen/C-1385-2013; du Rietz, Rickard/I-3794-2013; radford, David/A-3928-2015 OI Rudolph, Dirk/0000-0003-1199-3055; du Rietz, Rickard/0000-0002-9884-9058; NR 30 TC 19 Z9 19 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 2005 VL 71 IS 1 AR 011303 DI 10.1103/PhysRevC.71.011303 PG 5 WC Physics, Nuclear SC Physics GA 893EK UT WOS:000226701900003 ER PT J AU Arrington, J AF Arrington, J TI Extraction of two-photon contributions to the proton form factors SO PHYSICAL REVIEW C LA English DT Article ID POLARIZATION TRANSFER; 4-MOMENTUM TRANSFERS; SCATTERING AB Significant discrepancies have been observed between proton form factors as measured by Rosenbluth separation and polarization transfer techniques. There are indications that this difference may be caused by corrections to the one-photon exchange approximation that are not taken into account in standard radiative correction procedures. In this paper, we constrain the two-photon amplitudes by combining data from Rosenbluth, polarization transfer, and positron-proton scattering measurements. This allows a rough extraction of these two-photon effects in elastic electron-proton scattering and provides an improved extraction of the proton electromagnetic form factors. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RI Arrington, John/D-1116-2012 OI Arrington, John/0000-0002-0702-1328 NR 26 TC 45 Z9 45 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 2005 VL 71 IS 1 AR 015202 DI 10.1103/PhysRevC.71.015202 PG 8 WC Physics, Nuclear SC Physics GA 893EK UT WOS:000226701900044 ER PT J AU Aznauryan, IG Burkert, VD Egiyan, H Joo, K Minehart, R Smith, LC AF Aznauryan, IG Burkert, VD Egiyan, H Joo, K Minehart, R Smith, LC TI Electroexcitation of the P-33(1232), P-11(1440), D-13(1520), and S-11(1535) at Q(2)=0.4 and 0.65 (GeV/c)(2) SO PHYSICAL REVIEW C LA English DT Article ID TRANSITION FORM-FACTORS; RESONANCE REGION; PION ELECTROPRODUCTION; DELTA(1236) RESONANCE; NUCLEON RESONANCES; MOMENTUM-TRANSFERS; ISOBAR MODEL; QUARK-MODEL; SCATTERING; AMPLITUDES AB Using two approaches-dispersion relations and the isobar model-we have analyzed recent high precision CLAS data on cross sections of pi(0), pi(+), and eta electroproduction on protons, and the longitudinally polarized electron beam asymmetry for p(e(-->),e'p)pi(0) and p(e(-->),e'n)pi(+). The contributions of the resonances P-33(1232), P-11(1440), D-13(1520), and S-11(1535) to pi electroproduction and of S-11(1535) to eta electroproduction are found. The results obtained using the two approaches are in good agreement. There is also good agreement between amplitudes of the gamma*N-->S-11(1535) transition found in pi and eta electroproduction. For the first time accurate results are obtained for the longitudinal amplitudes of the P-11(1440), D-13(1520), and S-11(1535) electroexcitations on protons. A strong longitudinal response is found for the Roper resonance, which rules out presentation of this resonance as a hybrid state. C1 Yerevan Phys Inst, Yerevan 375036, Armenia. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Univ Connecticut, Storrs, CT 06269 USA. Univ Virginia, Charlottesville, VA 22901 USA. RP Yerevan Phys Inst, Yerevan 375036, Armenia. NR 51 TC 65 Z9 66 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 2005 VL 71 IS 1 AR 015201 DI 10.1103/PhysRevC.71.015201 PG 9 WC Physics, Nuclear SC Physics GA 893EK UT WOS:000226701900043 ER PT J AU Bardayan, DW Kozub, RL Smith, MS AF Bardayan, DW Kozub, RL Smith, MS TI F-19 alpha widths and the F-18+p reaction rates SO PHYSICAL REVIEW C LA English DT Article ID ELASTIC-SCATTERING; ENERGY-LEVELS; PARTICLES; NUCLEAR; N-15 AB Understanding the properties of F-19 levels in the range E-x=6.4-7.5 MeV is important for constraining the contributions of Ne-19 levels to the F-18(p,alpha)O-15 and F-18(p,gamma)Ne-19 thermonuclear reaction rates. We have reanalyzed N-15(alpha,alpha)N-15 data from H. Smotrich [Phys. Rev. 122, 232 (1961)] to determine properties of F-19 levels in this energy range. We find the energies and widths of broad levels to be different than previously reported and have set upper limits on the widths of postulated 3/2(+) resonances, analogs of which are important for the F-18+p rates. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Tennessee Technol Univ, Dept Phys, Cookeville, TN 38505 USA. RP Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 22 TC 14 Z9 14 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 2005 VL 71 IS 1 AR 018801 DI 10.1103/PhysRevC.71.018801 PG 4 WC Physics, Nuclear SC Physics GA 893EK UT WOS:000226701900058 ER PT J AU Chiang, WT Vanderhaeghen, M Yang, SN Drechsel, D AF Chiang, WT Vanderhaeghen, M Yang, SN Drechsel, D TI Unitary model for the gamma p -> gamma pi(0) p reaction and the magnetic dipole moment of the Delta(+)(1232) SO PHYSICAL REVIEW C LA English DT Article ID PION-PROTON BREMSSTRAHLUNG; CROSS-SECTIONS; LATTICE QCD; PHOTOPRODUCTION; SCATTERING; RESONANCE; DEPENDENCE AB Radiative pion photoproduction in the Delta(1232)-resonance region is studied with the aim of accessing the Delta(+)(1232) magnetic dipole moment. We present a unitary model of the gammap-->gammapiN (piN=pi(0)p, pi(+)n) reactions, where the piN rescattering is included in an onshell approximation. In this model, the low-energy theorem which couples the gammap-->gammapiN process in the limit of a soft final photon to the gammap-->piN process is exactly satisfied. We study the sensitivity of the gammap-->gammapi(0)p process at higher values of the final photon energy to the Delta(+)(1232) magnetic dipole moment. We compare our results with existing data and give predictions for forthcoming measurements of angular and energy distributions. It is found that the photon asymmetry and a helicity cross section are particularly sensitive to the Delta(+) magnetic dipole moment. C1 Natl Taiwan Univ, Dept Phys, Taipei 10617, Taiwan. Natl Taiwan Univ, Ctr Theoret Sci, Taipei 10617, Taiwan. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Jefferson Lab, Newport News, VA 23606 USA. Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. Univ Mainz, Inst Kernphys, D-55099 Mainz, Germany. RP Chiang, WT (reprint author), Natl Taiwan Univ, Dept Phys, Taipei 10617, Taiwan. NR 38 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 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 2005 VL 71 IS 1 AR 015204 DI 10.1103/PhysRevC.71.015204 PG 17 WC Physics, Nuclear SC Physics GA 893EK UT WOS:000226701900046 ER PT J AU Swiaatecki, WJ Siwek-Wilczynska, K Wilczynski, J AF Swiaatecki, WJ Siwek-Wilczynska, K Wilczynski, J TI Fusion by diffusion. II. Synthesis of transfermium elements in cold fusion reactions SO PHYSICAL REVIEW C LA English DT Article ID SUPER-HEAVY NUCLEI; CROSS-SECTIONS; LEVEL DENSITY; MASSES AB We describe a method of estimating cross sections for the synthesis of very heavy nuclei by the fusion of two lighter ones. The cross section is considered to be the product of three factors: the cross section for the projectile to overcome the Coulomb barrier, the probability that the resulting composite nucleus reaches the compound nucleus configuration by a shape fluctuation treated as a diffusion of probability in one dimension, and the probability that the excited compound nucleus survives fission. Semi-empirical formulas for the mean Coulomb barrier height and its distribution around the mean are constructed. After overcoming the Coulomb barrier the system is assumed to be injected into an "asymmetric fission valley" by a rapid growth of the neck between the target and projectile at approximately frozen asymmetry and elongation. Diffusion in the elongation coordinate in this valley can occasionally bring the system over the saddle separating the injection point from the compound nucleus configuration. This is the stage that accounts for the hindrance to fusion observed for very heavy reacting systems. The competition between deexcitation of the compound nucleus by neutron emission and fission is treated by standard methods, but an interesting insight allows one to predict in an elementary way the location of the maximum in the resulting excitation function. Adjusting one parameter in the theory causes the calculated peak cross sections to agree within about a factor of 2 or so with 12 measured or estimated values for "cold" one-neutron-out reactions where targets of Pb-208 and Bi-209 are bombarded with projectiles ranging from Ca-48 to Zn-70. The centroids of the excitation functions agree with theory to within 1 or 2 MeV for the six cases where they have been determined, and their widths are reproduced. "Hot" fusion reactions, where several neutrons are emitted, are not treated, except that a comparison is made between the hindrance factors in cold and hot reactions to make elements with atomic numbers 112 to 118. The calculated diffusive hindrances in the hot reactions are less unfavorable by 4 to 5 orders of magnitude. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. Andrzej Soltan Inst Nucl Studies, PL-05400 Otwock, Poland. RP Swiaatecki, WJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 35 TC 150 Z9 158 U1 1 U2 14 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 2005 VL 71 IS 1 AR 014602 DI 10.1103/PhysRevC.71.014602 PG 16 WC Physics, Nuclear SC Physics GA 893EK UT WOS:000226701900027 ER PT J AU Wang, Q Wang, XN AF Wang, Q Wang, XN TI Non-Abelian feature of parton energy loss in energy dependence of jet quenching in high-energy heavy-ion collisions SO PHYSICAL REVIEW C LA English DT Article ID NUCLEAR COLLISIONS; FRAGMENTATION FUNCTIONS; HADRON-PRODUCTION; GLUON RADIATION; ELLIPTIC FLOW; OPACITY; QCD; SCATTERING; ANISOTROPY; SPECTRA AB One of the non-Abelian features of parton energy loss is the ratio DeltaE(g)/DeltaE(q)=9/4 between gluon and quark jets. Since jet production rate is dominated by quark jets at high x(T)=2p(T)/roots and by gluon jets at low x(T), high p(T) hadron suppression in high-energy heavy-ion collisions should reflect such a non-Abelian feature. Within a leading-order perturbative QCD parton model that incorporates transverse expansion and Woods-Saxon nuclear distribution, the energy dependence of large p(T)similar to5-20 GeV/c hadron suppression is found to be sensitive to the non-Abelian feature of parton energy loss and could be tested by data from low-energy runs at Brookhaven National Laboratory's relativistic heavy-ion collider or data from the large hadron collider. C1 Univ Sci & Technol China, Dept Modern Phys, Hefei 230026, Anhui, Peoples R China. Goethe Univ Frankfurt, Inst Theoret Phys, D-60054 Frankfurt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Univ Sci & Technol China, Dept Modern Phys, Hefei 230026, Anhui, Peoples R China. NR 61 TC 31 Z9 31 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD JAN PY 2005 VL 71 IS 1 AR 014903 DI 10.1103/PhysRevC.71.014903 PG 6 WC Physics, Nuclear SC Physics GA 893EK UT WOS:000226701900040 ER PT J AU Acosta, D Adelman, J Affolder, T Akimoto, T Albrow, MG Ambrose, D Amerio, S Amidei, D Anastassov, A Anikeev, K Annovi, A Antos, J Aoki, M Apollinari, G Arisawa, T Arguin, JF Artikov, A Ashmanskas, W Attal, A Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Badgett, W Barbaro-Galtieri, A Barker, GJ Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Behari, S Belforte, S Bellettini, G Bellinger, J Ben-Haim, E Benjamin, D Beretvas, A Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Bocci, A Bodek, A Bolla, G Bolshov, A Booth, PSL Bortoletto, D Boudreau, J Bourov, S Bromberg, C Brubaker, E Budagov, J Budd, HS Burkett, K Busetto, G Bussey, P Byrum, KL Cabrera, S Campanelli, M Campbell, M Canepa, A Casarsa, M Carlsmith, D Carron, S Carosi, R Cavalli-Sforza, M Castro, A Catastini, P Cauz, D Cerri, A Cerri, C Cerrito, L Chapman, J Chen, C Chen, YC Chertok, M Chiarelli, G Chlachidze, G Chlebana, F Cho, I Cho, K Chokheli, D Chu, ML Chuang, S Chung, JY Chung, WH Chung, YS Ciobanu, CI Ciocci, MA Clark, AG Clark, D Coca, M Connolly, A Convery, M Conway, J Cooper, B Cordelli, M Cortiana, G Cranshaw, J Cuevas, J Culbertson, R Currat, C Cyr, D Dagenhart, D Da Ronco, S D'Auria, S de Barbaro, P De Cecco, S De Lentdecker, G Dell'Agnello, S Dell'Orso, M Demers, S Demortier, L Deninno, M De Pedis, D Derwent, PF Dionisi, C Dittmann, JR Doksus, P Dominguez, A Donati, S Donega, M Donini, J D'Onofrio, M Dorigo, T Drollinger, V Ebina, K Eddy, N Ely, R Erbacher, R Erdmann, M Errede, D Errede, S Eusebi, R Fang, HC Farrington, S Fedorko, I Feild, RG Feindt, M Fernandez, JP Ferretti, C Field, RD Fiori, I Flanagan, G Flaugher, B Flores-Castillo, LR Foland, A Forrester, S Foster, GW Franklin, M Freeman, JC Frisch, H Fujii, Y Furic, I Gajjar, A Gallas, A Galyardt, J Gallinaro, M Garcia-Sciveres, M Garfinkel, AF Gay, C Gerberich, H Gerdes, DW Gerchtein, E Giagu, S Giannetti, P Gibson, A Gibson, K Ginsburg, C Giolo, K Giordani, M Giurgiu, G Glagolev, V Glenzinski, D Gold, M Goldschmidt, N Goldstein, D Goldstein, J Gomez, G Gomez-Ceballos, G Goncharov, M Gonzalez, O Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Gresele, A Griffiths, M Grosso-Pilcher, C Grundler, U Guenther, M da Costa, JG Haber, C Hahn, K Hahn, SR Halkiadakis, E Hamilton, A Han, BY Handler, R Happacher, F Hara, K Hare, M Harr, RF Harris, RM Hartmann, F Hatakeyama, K Hauser, J Hays, C Hayward, H Heider, E Heinemann, B Heinrich, J Hennecke, M Herndon, M Hill, C Hirschbuehl, D Hocker, A Hoffman, KD Holloway, A Hou, S Houlden, MA Huffman, BT Huang, Y Hughes, RE Huston, J Ikado, K Incandela, J Introzzi, G Iori, M Ishizawa, Y Issever, C Ivanov, A Iwata, Y Iyutin, B James, E Jang, D Jarrell, J Jeans, D Jensen, H Jeon, EJ Jones, M Joo, KK Jun, S Junk, T Kamon, T Kang, J Unel, MK Karchin, PE Kartal, S Kato, Y Kemp, Y Kephart, R Kerzel, U Khotilovich, V Kilminster, B Kim, DH Kim, HS Kim, JE Kim, MJ Kim, MS Kim, SB Kim, SH Kim, TH Kim, YK King, BT Kirby, M Kirsch, L Klimenko, S Knuteson, B Ko, BR Kobayashi, H Koehn, P Kong, DJ Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kotelnikov, K Kotwal, AV Kovalev, A Kraus, J Kravchenko, I Kreymer, A Kroll, J Kruse, M Krutelyov, V Kuhlmann, SE Kuznetsova, N Laasanen, AT Lai, S Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lannon, K Lath, A Latino, G Lauhakangas, R Lazzizzera, I Le, Y Lecci, C LeCompte, T Lee, J Lee, J Lee, SW Lefevre, R Leonardo, N Leone, S Lewis, JD Li, K Lin, C Lin, CS Lindgren, M Liss, TM Litvintsev, DO Liu, T Liu, Y Lockyer, NS Loginov, A Loreti, M Loverre, P Lu, RS Lucchesi, D Lujan, P Lukens, P Lungu, G Lyons, L Lys, J Lysak, R MacQueen, D Madrak, R Maeshima, K Maksimovic, P Malferrari, L Manca, G Marginean, R Martin, M Martin, A Martin, V Martinez, M Maruyama, T Matsunaga, H Mattson, M Mazzanti, P McFarland, KS McGivern, D McIntyre, PM McNamara, P NcNulty, R Menzemer, S Menzione, A Merkel, P Mesropian, C Messina, A Miao, T Miladinovic, N Miller, L Miller, R Miller, JS Miquel, R Miscetti, S Mitselmakher, G Miyamoto, A Miyazaki, Y Moggi, N Mohr, B Moore, R Morello, M Mukherjee, A Mulhearn, M Muller, T Mumford, R Munar, A Murat, P Nachtman, J Nahn, S Nakamura, I Nakano, I Napier, A Napora, R Naumov, D Necula, V Niell, F Nielsen, J Nelson, C Nelson, T Neu, C Neubauer, MS Newman-Holmes, C Nicollerat, AS Nigmanov, T Nodulman, L Norniella, O Oesterberg, K Ogawa, T Oh, SH Oh, YD Ohsugi, T Okusawa, T Oldeman, R Orava, R Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pashapour, S Patrick, J Pauletta, G Paulini, M Pauly, T Paus, C Pellett, D Penzo, A Phillips, TJ Piacentino, G Piedra, J Pitts, KT Plager, C Pompos, A Pondrom, L Pope, G Poukhov, O Prakoshyn, F Pratt, T Pronko, A Proudfoot, J Ptohos, F Punzi, G Rademacker, J Rakitine, A Rappoccio, S Ratnikov, F Ray, H Reichold, A Reisert, B Rekovic, V Renton, P Rescigno, M Rimondi, F Rinnert, K Ristori, L Robertson, WJ Robson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Rott, C Russ, J Ruiz, A Ryan, D Saarikko, H Sabik, S Safonov, A St Denis, R Sakumoto, WK Salamanna, G Saltzberg, D Sanchez, C Sansoni, A Santi, L Sarkar, S Sato, K Savard, P Savoy-Navarro, A Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scribano, A Scuri, F Sedov, A Seidel, S Seiya, Y Semeria, F Sexton-Kennedy, L Sfiligoi, I Shapiro, MD Shears, T Shepard, PF Shimojima, M Shochet, M Shon, Y Shreyber, I Sidoti, A Siegrist, J Siket, M Sill, A Sinervo, P Sisakyan, A Skiba, A Slaughter, AJ Sliwa, K Smirnov, D Smith, JR Snider, FD Snihur, R Somalwar, SV Spalding, J Spezziga, M Spiegel, L Spinella, F Spiropulu, M Squillacioti, P Stadie, H Stefanini, A Stelzer, B Stelzer-Chilton, O Strologas, J Stuart, D Sukhanov, A Sumorok, K Sun, H Suzuki, T Taffard, A Tafirout, R Takach, SF Takano, H Takashima, R Takeuchi, Y Takikawa, K Tanaka, M Tanaka, R Tanimoto, N Tapprogge, S Tecchio, M Teng, PK Terashi, K Tesarek, RJ Tether, S Thom, J Thompson, AS Thomson, E Tipton, P Tiwari, V Tkaczyk, S Toback, D Tollefson, K Tomura, T Tonelli, D Tonnesmann, M Torre, S Torretta, D Tourneur, S Trischuk, W Tseng, J Tsuchiya, R Tsuno, S Tsybychev, D Turini, N Turner, M Ukegawa, F Unverhau, T Uozumi, S Usynin, D Vacavant, L Vaiciulis, A Varganov, A Vataga, E Vejcik, S Velev, G Veszpremi, V Veramendi, G Vickey, T Vidal, R Vila, I Vilar, R Vollrath, I Volobouev, I von der Mey, M Wagner, P Wagner, RG Wagner, RL Wagner, W Wallny, R Walter, T Yamashita, T Yamamoto, K Wan, Z Wang, MJ Wang, SM Warburton, A Ward, B Waschke, S Waters, D Watts, T Weber, M Wester, WC Whitehouse, B Wicklund, AB Wicklund, E Williams, HH Wilson, P Winer, BL Wittich, P Wolbers, S Wolter, M Worcester, M Worm, S Wright, T Wu, X Wurthwein, F Wyatt, A Yagil, A Yang, UK Yao, W Yeh, GP Yi, K Yoh, J Yoon, P Yorita, K Yoshida, T Yu, I Yu, S Yu, Z Yun, JC Zanello, L Zanetti, A Zaw, I Zetti, F Zhou, J Zsenei, A Zucchelli, S AF Acosta, D Adelman, J Affolder, T Akimoto, T Albrow, MG Ambrose, D Amerio, S Amidei, D Anastassov, A Anikeev, K Annovi, A Antos, J Aoki, M Apollinari, G Arisawa, T Arguin, JF Artikov, A Ashmanskas, W Attal, A Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Badgett, W Barbaro-Galtieri, A Barker, GJ Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Behari, S Belforte, S Bellettini, G Bellinger, J Ben-Haim, E Benjamin, D Beretvas, A Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Bocci, A Bodek, A Bolla, G Bolshov, A Booth, PSL Bortoletto, D Boudreau, J Bourov, S Bromberg, C Brubaker, E Budagov, J Budd, HS Burkett, K Busetto, G Bussey, P Byrum, KL Cabrera, S Campanelli, M Campbell, M Canepa, A Casarsa, M Carlsmith, D Carron, S Carosi, R Cavalli-Sforza, M Castro, A Catastini, P Cauz, D Cerri, A Cerri, C Cerrito, L Chapman, J Chen, C Chen, YC Chertok, M Chiarelli, G Chlachidze, G Chlebana, F Cho, I Cho, K Chokheli, D Chu, ML Chuang, S Chung, JY Chung, WH Chung, YS Ciobanu, CI Ciocci, MA Clark, AG Clark, D Coca, M Connolly, A Convery, M Conway, J Cooper, B Cordelli, M Cortiana, G Cranshaw, J Cuevas, J Culbertson, R Currat, C Cyr, D Dagenhart, D Da Ronco, S D'Auria, S de Barbaro, P De Cecco, S De Lentdecker, G Dell'Agnello, S Dell'Orso, M Demers, S Demortier, L Deninno, M De Pedis, D Derwent, PF Dionisi, C Dittmann, JR Doksus, P Dominguez, A Donati, S Donega, M Donini, J D'Onofrio, M Dorigo, T Drollinger, V Ebina, K Eddy, N Ely, R Erbacher, R Erdmann, M Errede, D Errede, S Eusebi, R Fang, HC Farrington, S Fedorko, I Feild, RG Feindt, M Fernandez, JP Ferretti, C Field, RD Fiori, I Flanagan, G Flaugher, B Flores-Castillo, LR Foland, A Forrester, S Foster, GW Franklin, M Freeman, JC Frisch, H Fujii, Y Furic, I Gajjar, A Gallas, A Galyardt, J Gallinaro, M Garcia-Sciveres, M Garfinkel, AF Gay, C Gerberich, H Gerdes, DW Gerchtein, E Giagu, S Giannetti, P Gibson, A Gibson, K Ginsburg, C Giolo, K Giordani, M Giurgiu, G Glagolev, V Glenzinski, D Gold, M Goldschmidt, N Goldstein, D Goldstein, J Gomez, G Gomez-Ceballos, G Goncharov, M Gonzalez, O Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Gresele, A Griffiths, M Grosso-Pilcher, C Grundler, U Guenther, M da Costa, JG Haber, C Hahn, K Hahn, SR Halkiadakis, E Hamilton, A Han, BY Handler, R Happacher, F Hara, K Hare, M Harr, RF Harris, RM Hartmann, F Hatakeyama, K Hauser, J Hays, C Hayward, H Heider, E Heinemann, B Heinrich, J Hennecke, M Herndon, M Hill, C Hirschbuehl, D Hocker, A Hoffman, KD Holloway, A Hou, S Houlden, MA Huffman, BT Huang, Y Hughes, RE Huston, J Ikado, K Incandela, J Introzzi, G Iori, M Ishizawa, Y Issever, C Ivanov, A Iwata, Y Iyutin, B James, E Jang, D Jarrell, J Jeans, D Jensen, H Jeon, EJ Jones, M Joo, KK Jun, S Junk, T Kamon, T Kang, J Unel, MK Karchin, PE Kartal, S Kato, Y Kemp, Y Kephart, R Kerzel, U Khotilovich, V Kilminster, B Kim, DH Kim, HS Kim, JE Kim, MJ Kim, MS Kim, SB Kim, SH Kim, TH Kim, YK King, BT Kirby, M Kirsch, L Klimenko, S Knuteson, B Ko, BR Kobayashi, H Koehn, P Kong, DJ Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kotelnikov, K Kotwal, AV Kovalev, A Kraus, J Kravchenko, I Kreymer, A Kroll, J Kruse, M Krutelyov, V Kuhlmann, SE Kuznetsova, N Laasanen, AT Lai, S Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lannon, K Lath, A Latino, G Lauhakangas, R Lazzizzera, I Le, Y Lecci, C LeCompte, T Lee, J Lee, J Lee, SW Lefevre, R Leonardo, N Leone, S Lewis, JD Li, K Lin, C Lin, CS Lindgren, M Liss, TM Litvintsev, DO Liu, T Liu, Y Lockyer, NS Loginov, A Loreti, M Loverre, P Lu, RS Lucchesi, D Lujan, P Lukens, P Lungu, G Lyons, L Lys, J Lysak, R MacQueen, D Madrak, R Maeshima, K Maksimovic, P Malferrari, L Manca, G Marginean, R Martin, M Martin, A Martin, V Martinez, M Maruyama, T Matsunaga, H Mattson, M Mazzanti, P McFarland, KS McGivern, D McIntyre, PM McNamara, P NcNulty, R Menzemer, S Menzione, A Merkel, P Mesropian, C Messina, A Miao, T Miladinovic, N Miller, L Miller, R Miller, JS Miquel, R Miscetti, S Mitselmakher, G Miyamoto, A Miyazaki, Y Moggi, N Mohr, B Moore, R Morello, M Mukherjee, A Mulhearn, M Muller, T Mumford, R Munar, A Murat, P Nachtman, J Nahn, S Nakamura, I Nakano, I Napier, A Napora, R Naumov, D Necula, V Niell, F Nielsen, J Nelson, C Nelson, T Neu, C Neubauer, MS Newman-Holmes, C Nicollerat, AS Nigmanov, T Nodulman, L Norniella, O Oesterberg, K Ogawa, T Oh, SH Oh, YD Ohsugi, T Okusawa, T Oldeman, R Orava, R Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pashapour, S Patrick, J Pauletta, G Paulini, M Pauly, T Paus, C Pellett, D Penzo, A Phillips, TJ Piacentino, G Piedra, J Pitts, KT Plager, C Pompos, A Pondrom, L Pope, G Poukhov, O Prakoshyn, F Pratt, T Pronko, A Proudfoot, J Ptohos, F Punzi, G Rademacker, J Rakitine, A Rappoccio, S Ratnikov, F Ray, H Reichold, A Reisert, B Rekovic, V Renton, P Rescigno, M Rimondi, F Rinnert, K Ristori, L Robertson, WJ Robson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Rott, C Russ, J Ruiz, A Ryan, D Saarikko, H Sabik, S Safonov, A St Denis, R Sakumoto, WK Salamanna, G Saltzberg, D Sanchez, C Sansoni, A Santi, L Sarkar, S Sato, K Savard, P Savoy-Navarro, A Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scribano, A Scuri, F Sedov, A Seidel, S Seiya, Y Semeria, F Sexton-Kennedy, L Sfiligoi, I Shapiro, MD Shears, T Shepard, PF Shimojima, M Shochet, M Shon, Y Shreyber, I Sidoti, A Siegrist, J Siket, M Sill, A Sinervo, P Sisakyan, A Skiba, A Slaughter, AJ Sliwa, K Smirnov, D Smith, JR Snider, FD Snihur, R Somalwar, SV Spalding, J Spezziga, M Spiegel, L Spinella, F Spiropulu, M Squillacioti, P Stadie, H Stefanini, A Stelzer, B Stelzer-Chilton, O Strologas, J Stuart, D Sukhanov, A Sumorok, K Sun, H Suzuki, T Taffard, A Tafirout, R Takach, SF Takano, H Takashima, R Takeuchi, Y Takikawa, K Tanaka, M Tanaka, R Tanimoto, N Tapprogge, S Tecchio, M Teng, PK Terashi, K Tesarek, RJ Tether, S Thom, J Thompson, AS Thomson, E Tipton, P Tiwari, V Tkaczyk, S Toback, D Tollefson, K Tomura, T Tonelli, D Tonnesmann, M Torre, S Torretta, D Tourneur, S Trischuk, W Tseng, J Tsuchiya, R Tsuno, S Tsybychev, D Turini, N Turner, M Ukegawa, F Unverhau, T Uozumi, S Usynin, D Vacavant, L Vaiciulis, A Varganov, A Vataga, E Vejcik, S Velev, G Veszpremi, V Veramendi, G Vickey, T Vidal, R Vila, I Vilar, R Vollrath, I Volobouev, I von der Mey, M Wagner, P Wagner, RG Wagner, RL Wagner, W Wallny, R Walter, T Yamashita, T Yamamoto, K Wan, Z Wang, MJ Wang, SM Warburton, A Ward, B Waschke, S Waters, D Watts, T Weber, M Wester, WC Whitehouse, B Wicklund, AB Wicklund, E Williams, HH Wilson, P Winer, BL Wittich, P Wolbers, S Wolter, M Worcester, M Worm, S Wright, T Wu, X Wurthwein, F Wyatt, A Yagil, A Yang, UK Yao, W Yeh, GP Yi, K Yoh, J Yoon, P Yorita, K Yoshida, T Yu, I Yu, S Yu, Z Yun, JC Zanello, L Zanetti, A Zaw, I Zetti, F Zhou, J Zsenei, A Zucchelli, S CA CDF Collaboration TI Search for electroweak single-top-quark production in p(p)over-bar collisions at root s=1.96 TeV SO PHYSICAL REVIEW D LA English DT Article ID RESUMMATION; PHYSICS; QCD AB We report on a search for standard model t-channel and s-channel single-top quark production in p (p) over bar collisions at a center of mass energy of 1.96 TeV. We use a data sample corresponding to 162 pb(-1) recorded by the upgraded collider detector at Fermilab. We find no significant evidence for electroweak top quark production and set upper limits at the 95% confidence level on the production cross section, consistent with the standard model: 10.1 pb for the t-channel, 13.6 pb for the s-channel and 17.8 pb for the combined cross section of t- and s-channel. C1 Univ Florida, Gainesville, FL 32611 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Autonoma Barcelona, Inst Fis Altes Energies, E-08193 Barcelona, Spain. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Cantabria, Inst Fis Cantabria, CSIC, E-39005 Santander, Spain. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Harvard Univ, Cambridge, MA 02138 USA. Univ Helsinki, Helsinki Grp, Helsinki Inst Phys, FIN-00044 Helsinki, Finland. Univ Helsinki, Div High Energy Phys, Dept Phys Sci, FIN-00044 Helsinki, Finland. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. High Energy Accelerator Res Org, KEK, Tsukuba, Ibaraki 305, Japan. Kyungpook Natl Univ, Ctr High Energy Phys, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Liverpool, Liverpool L69 7ZE, Merseyside, England. UCL, London WC1E 6BT, England. MIT, Cambridge, MA 02139 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Inst Theoret & Expt Phys, Moscow 117259, Russia. Univ New Mexico, Albuquerque, NM 87131 USA. Northwestern Univ, Evanston, IL 60208 USA. Ohio State Univ, Columbus, OH 43210 USA. Okayama Univ, Okayama 7008530, Japan. Osaka City Univ, Osaka 588, Japan. Univ Oxford, Oxford OX1 3RH, England. Univ Padua, Ist Nazl Fis Nucl, Sez Padova Trento, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Univ Roma La Sapienza, Ist Nazl Fis Nucl, Sez Roma 1, I-00185 Rome, Italy. Rutgers State Univ, Piscataway, NJ 08855 USA. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Wayne State Univ, Detroit, MI 48201 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Univ Florida, Gainesville, FL 32611 USA. RI Prokoshin, Fedor/E-2795-2012; Introzzi, Gianluca/K-2497-2015; Gorelov, Igor/J-9010-2015; Leonardo, Nuno/M-6940-2016; Warburton, Andreas/N-8028-2013; Kim, Soo-Bong/B-7061-2014; Lysak, Roman/H-2995-2014; Gallas Torreira, Abraham Antonio/K-6508-2014; Scodellaro, Luca/K-9091-2014; Connolly, Amy/J-3958-2013; Paulini, Manfred/N-7794-2014; Russ, James/P-3092-2014; Lazzizzera, Ignazio/E-9678-2015; vilar, rocio/P-8480-2014; Cabrera Urban, Susana/H-1376-2015; Cavalli-Sforza, Matteo/H-7102-2015; ciocci, maria agnese /I-2153-2015; Lancaster, Mark/C-1693-2008; Ruiz, Alberto/E-4473-2011; Robson, Aidan/G-1087-2011; De Cecco, Sandro/B-1016-2012; Wolter, Marcin/A-7412-2012; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; manca, giulia/I-9264-2012; Amerio, Silvia/J-4605-2012; Punzi, Giovanni/J-4947-2012; messina, andrea/C-2753-2013; Annovi, Alberto/G-6028-2012; Chiarelli, Giorgio/E-8953-2012; Ivanov, Andrew/A-7982-2013 OI Prokoshin, Fedor/0000-0001-6389-5399; Introzzi, Gianluca/0000-0002-1314-2580; Gorelov, Igor/0000-0001-5570-0133; Leonardo, Nuno/0000-0002-9746-4594; Warburton, Andreas/0000-0002-2298-7315; Gallas Torreira, Abraham Antonio/0000-0002-2745-7954; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Russ, James/0000-0001-9856-9155; Lazzizzera, Ignazio/0000-0001-5092-7531; ciocci, maria agnese /0000-0003-0002-5462; Ruiz, Alberto/0000-0002-3639-0368; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Annovi, Alberto/0000-0002-4649-4398; Chiarelli, Giorgio/0000-0001-9851-4816; Ivanov, Andrew/0000-0002-9270-5643 NR 24 TC 37 Z9 37 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 012005 DI 10.1103/PhysRevD.71.012005 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300011 ER PT J AU Agashe, K Perez, G Soni, A AF Agashe, K Perez, G Soni, A TI Flavor structure of warped extra dimension models SO PHYSICAL REVIEW D LA English DT Review ID ELECTRIC-DIPOLE MOMENT; RADIATIVE B-DECAYS; CP-VIOLATION; COMPOSITE HIGGS; TOP-QUARK; GAUGE-THEORY; PHYSICS; ASYMMETRIES; MASS; COMPACTIFICATION AB We recently showed that warped extra-dimensional models with bulk custodial symmetry and few TeV Kaluza-Klein (KK) masses lead to striking signals at B factories. In this paper, using a spurion analysis, we systematically study the flavor structure of models that belong to the above class. In particular we find that the profiles of the zero modes, which are similar in all these models, essentially control the underlying flavor structure. This implies that our results are robust and model independent in this class of models. We discuss in detail the origin of the signals in B physics. We also briefly study other new physics signatures that arise in rare K decays (K-->pinunu), in rare top decays [t-->cgamma(Z,gluon)], and the possibility of CP asymmetries in D-0 decays to CP eigenstates such as K(S)pi(0) and others. Finally we demonstrate that with light KK masses, similar to3 TeV, the above class of models with anarchic 5D Yukawas has a "CP problem" since contributions to the neutron electric dipole moment are roughly 20 times larger than the current experimental bound. Using AdS/CFT correspondence, these extra-dimensional models are dual to a purely 4D strongly coupled conformal Higgs sector thus enhancing their appeal. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Brookhaven Natl Lab, High Energy Theory Grp, Upton, NY 11973 USA. RP Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. EM kagashe@pha.jhu.edu; Gperez@lbl.gov; soni@bnl.gov NR 105 TC 295 Z9 295 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 016002 DI 10.1103/PhysRevD.71.016002 PG 26 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300080 ER PT J AU Airapetian, A Akopov, N Akopov, Z Amarian, M Ammosov, VV Andrus, A Aschenauer, EC Augustyniak, W Avakian, R Avetissian, A Avetissian, E Bailey, P Baturin, V Baumgarten, C Beckmann, M Belostotski, S Bernreuther, S Bianchi, N Blok, HP Blumlein, J Bottcher, H Borissov, A Borysenko, A Bouwhuis, M Brack, J Brull, A Bryzgalov, V Capitani, GP Chiang, HC Ciullo, G Contalbrigo, M Dalpiaz, PF De Leo, R De Nardo, L De Sanctis, E Devitsin, E Di Nezza, P Duren, M Ehrenfried, M Elalaoui-Moulay, A Elbakian, G Ellinghaus, F Elschenbroich, U Ely, J Fabbri, R Fantoni, A Fechtchenko, A Felawka, L Fox, B Franz, J Frullani, S Gapienko, G Gapienko, V Garibaldi, F Garrow, K Garutti, E Gaskell, D Gavrilov, G Gharibyan, V Graw, G Grebeniouk, O Greeniaus, LG Gregor, IM Hafidi, K Hartig, M Hasch, D Heesbeen, D Henoch, M Hertenberger, R Hesselink, WHA Hillenbrand, A Hoek, M Holler, Y Hommez, B Iarygin, G Ivanilov, A Izotov, A Jackson, HE Jgoun, A Kaiser, R Kinney, E Kisselev, A Konigsmann, K Kopytin, M Korotkov, V Kozlov, V Krauss, B Krivokhijine, VG Lagamba, L Lapikas, L Laziev, A Lenisa, P Liebing, P Lindemann, T Linden-Levy, LA Lipka, K Lorenzon, W Lu, J Maiheu, B Makins, NCR Marianski, B Marukyan, H Masoli, F Mexner, V Meyners, N Mikloukho, O Miller, CA Miyachi, Y Muccifora, V Nagaitsev, A Nappi, E Naryshkin, Y Nass, A Negodaev, M Nowak, WD Oganessyan, K Ohsuga, H Pickert, N Potashov, S Potterveld, DH Raithel, M Reggiani, D Reimer, PE Reischl, A Reolon, AR Riedl, C Rith, K Rosner, G Rostomyan, A Rubacek, L Rubin, J Ryckbosch, D Salomatin, Y Sanjiev, I Savin, I Scarlett, C Schafer, A Schill, C Schnell, G Schuler, KP Schwind, A Seele, J Seidl, R Seitz, B Shanidze, R Shearer, C Shibata, TA Shutov, V Simani, MC Sinram, K Stancari, M Statera, M Steffens, E Steijger, JJM Stenzel, H Stewart, J Stosslein, U Tait, P Tanaka, H Taroian, S Tchuiko, B Terkulov, A Tkabladze, A Trzcinski, A Tytgat, M Vandenbroucke, A van der Nat, P van der Steenhoven, G Vetterli, MC Vikhrov, V Vincter, MG Vogel, C Vogt, M Volmer, J Weiskopf, C Wendland, J Wilbert, J Smit, GY Yen, S Zihlmann, B Zohrabian, H Zupranski, P AF Airapetian, A Akopov, N Akopov, Z Amarian, M Ammosov, VV Andrus, A Aschenauer, EC Augustyniak, W Avakian, R Avetissian, A Avetissian, E Bailey, P Baturin, V Baumgarten, C Beckmann, M Belostotski, S Bernreuther, S Bianchi, N Blok, HP Blumlein, J Bottcher, H Borissov, A Borysenko, A Bouwhuis, M Brack, J Brull, A Bryzgalov, V Capitani, GP Chiang, HC Ciullo, G Contalbrigo, M Dalpiaz, PF De Leo, R De Nardo, L De Sanctis, E Devitsin, E Di Nezza, P Duren, M Ehrenfried, M Elalaoui-Moulay, A Elbakian, G Ellinghaus, F Elschenbroich, U Ely, J Fabbri, R Fantoni, A Fechtchenko, A Felawka, L Fox, B Franz, J Frullani, S Gapienko, G Gapienko, V Garibaldi, F Garrow, K Garutti, E Gaskell, D Gavrilov, G Gharibyan, V Graw, G Grebeniouk, O Greeniaus, LG Gregor, IM Hafidi, K Hartig, M Hasch, D Heesbeen, D Henoch, M Hertenberger, R Hesselink, WHA Hillenbrand, A Hoek, M Holler, Y Hommez, B Iarygin, G Ivanilov, A Izotov, A Jackson, HE Jgoun, A Kaiser, R Kinney, E Kisselev, A Konigsmann, K Kopytin, M Korotkov, V Kozlov, V Krauss, B Krivokhijine, VG Lagamba, L Lapikas, L Laziev, A Lenisa, P Liebing, P Lindemann, T Linden-Levy, LA Lipka, K Lorenzon, W Lu, J Maiheu, B Makins, NCR Marianski, B Marukyan, H Masoli, F Mexner, V Meyners, N Mikloukho, O Miller, CA Miyachi, Y Muccifora, V Nagaitsev, A Nappi, E Naryshkin, Y Nass, A Negodaev, M Nowak, WD Oganessyan, K Ohsuga, H Pickert, N Potashov, S Potterveld, DH Raithel, M Reggiani, D Reimer, PE Reischl, A Reolon, AR Riedl, C Rith, K Rosner, G Rostomyan, A Rubacek, L Rubin, J Ryckbosch, D Salomatin, Y Sanjiev, I Savin, I Scarlett, C Schafer, A Schill, C Schnell, G Schuler, KP Schwind, A Seele, J Seidl, R Seitz, B Shanidze, R Shearer, C Shibata, TA Shutov, V Simani, MC Sinram, K Stancari, M Statera, M Steffens, E Steijger, JJM Stenzel, H Stewart, J Stosslein, U Tait, P Tanaka, H Taroian, S Tchuiko, B Terkulov, A Tkabladze, A Trzcinski, A Tytgat, M Vandenbroucke, A van der Nat, P van der Steenhoven, G Vetterli, MC Vikhrov, V Vincter, MG Vogel, C Vogt, M Volmer, J Weiskopf, C Wendland, J Wilbert, J Smit, GY Yen, S Zihlmann, B Zohrabian, H Zupranski, P CA HERMES Collaboration TI Quark helicity distributions in the nucleon for up, down, and strange quarks from semi-inclusive deep-inelastic scattering SO PHYSICAL REVIEW D LA English DT Article ID TO-LEADING ORDER; SMALL-X-BEHAVIOR; POLARIZED PARTON DISTRIBUTIONS; PHYSICS EVENT GENERATION; MUON PROTON-SCATTERING; INTERNAL GAS-TARGET; N-C LIMIT; FLAVOR ASYMMETRY; SPIN STRUCTURE; HERMES EXPERIMENT AB Polarized deep-inelastic scattering data on longitudinally polarized hydrogen and deuterium targets have been used to determine double-spin asymmetries of cross sections. Inclusive and semi-inclusive asymmetries for the production of positive and negative pions from hydrogen were obtained in a reanalysis of previously published data. Inclusive and semi-inclusive asymmetries for the production of negative and positive pions and kaons were measured on a polarized deuterium target. The separate helicity densities for the up and down quarks and the anti-up, anti-down, and strange sea quarks were computed from these asymmetries in a "leading order" QCD analysis. The polarization of the up-quark is positive and that of the down-quark is negative. All extracted sea quark polarizations are consistent with zero, and the light quark sea helicity densities are flavor symmetric within the experimental uncertainties. First and second moments of the extracted quark helicity densities in the measured range are consistent with fits of inclusive data. C1 Yerevan Phys Inst, Yerevan 375036, Armenia. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Ist Nazl Fis Nucl, Sez Bari, I-70124 Bari, Italy. Univ Colorado, Nucl Phys Lab, Boulder, CO 80309 USA. DESY, Deutsch Elekt Synchrotron, D-22603 Hamburg, Germany. DESY Zeuthen, D-15738 Zeuthen, Germany. Joint Inst Nucl Res, Dubna 141980, Russia. Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany. Univ Ferrara, Ist Nazl Fis Nucl, Sez Ferrara, I-44100 Ferrara, Italy. Univ Ferrara, Dipartimento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Freiburg, Fak Phys, D-79104 Freiburg, Germany. Univ Ghent, Dept Subatom & Radiat Phys, B-9000 Ghent, Belgium. Univ Giessen, Inst Phys, D-35392 Giessen, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. PN Lebedev Phys Inst, Moscow 117924, Russia. Univ Munich, Sekt Phys, D-85748 Garching, Germany. NIKHEF, NL-1009 DB Amsterdam, Netherlands. Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Inst High Energy Phys, Moscow 142281, Russia. Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. Ist Super Sanita, Ist Nazl Fis Nucl, Sez Roma 1, Grp Sanita & Phys Lab, I-00161 Rome, Italy. Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. TRIUMF, Vancouver, BC V6T 2A3, Canada. Tokyo Inst Technol, Dept Phys, Tokyo 152, Japan. Free Univ Amsterdam, Dept Phys & Astron, NL-1081 HV Amsterdam, Netherlands. Soltan Inst Nucl Studies, PL-00689 Warsaw, Poland. RP Yerevan Phys Inst, Yerevan 375036, Armenia. RI Gavrilov, Gennady/C-6260-2013; Negodaev, Mikhail/A-7026-2014; Reimer, Paul/E-2223-2013; El Alaoui, Ahmed/B-4638-2015; Kozlov, Valentin/M-8000-2015; Terkulov, Adel/M-8581-2015; OI Hoek, Matthias/0000-0002-1893-8764 NR 100 TC 223 Z9 223 U1 1 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 012003 DI 10.1103/PhysRevD.71.012003 PG 36 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300009 ER PT J AU Alexopoulos, T Andre, T Arenton, M Barbosa, RF Barker, AR Bellantoni, L Bellavance, A Blucher, E Bock, GJ Cheu, E Childress, S Coleman, R Corcoran, MD Cox, B Erwin, AR Ford, R Glazov, A Golossanov, A Graham, J Hamm, J Hanagaki, K Hsiung, YB Huang, H Jejer, V Jensen, DA Kessler, R Kobrak, HGE Kotera, K LaDue, J Ledovskoy, A McBride, PL Monnier, E Nelson, KS Nguyen, H Niclasen, R Prasad, V Qi, XR Ramberg, EJ Ray, RE Ronquest, M Santos, E Shanahan, P Shields, J Slater, W Smith, D Solomey, N Swallow, EC Toale, PA Tschirhart, R Wah, YW Wang, J White, HB Whitmore, J Wilking, M Winstein, B Winston, R Worcester, ET Yamanaka, T Zimmerman, ED AF Alexopoulos, T Andre, T Arenton, M Barbosa, RF Barker, AR Bellantoni, L Bellavance, A Blucher, E Bock, GJ Cheu, E Childress, S Coleman, R Corcoran, MD Cox, B Erwin, AR Ford, R Glazov, A Golossanov, A Graham, J Hamm, J Hanagaki, K Hsiung, YB Huang, H Jejer, V Jensen, DA Kessler, R Kobrak, HGE Kotera, K LaDue, J Ledovskoy, A McBride, PL Monnier, E Nelson, KS Nguyen, H Niclasen, R Prasad, V Qi, XR Ramberg, EJ Ray, RE Ronquest, M Santos, E Shanahan, P Shields, J Slater, W Smith, D Solomey, N Swallow, EC Toale, PA Tschirhart, R Wah, YW Wang, J White, HB Whitmore, J Wilking, M Winstein, B Winston, R Worcester, ET Yamanaka, T Zimmerman, ED CA KTeV Collaboration TI Measurements of the branching fraction and decay distributions for K-L ->pi(+/-)mu(-/+)nu gamma and K-L ->pi(+/-)e(-/+)nu gamma SO PHYSICAL REVIEW D LA English DT Article ID RADIATIVE-CORRECTIONS AB We present measurements of R(Kl3gamma)equivalent toGamma(K-L-->pi(+/-)l(-/+)nugamma;E-gamma(star)>10 MeV)/Gamma(K-L-->pi(+/-)l(-/+)nu), where l=mu or e, and E-gamma(star) is the photon energy in the kaon rest frame. These measurements are based on K-L decays collected in 1997 by the KTeV (E832) experiment at Fermilab. With samples of 1385 K-L-->pi(+/-)mu(-/+)nugamma and 14221 K-L-->pi(+/-)e(-/+)nugamma candidates, we find R-Kmu3gamma=(0.530+/-0.019)% and R-Ke3gamma=(4.942+/-0.062)%. We also examine distributions of photon energy and lepton-photon angle. C1 Univ Wisconsin, Madison, WI 53706 USA. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Colorado, Boulder, CO 80309 USA. Elmhurst Coll, Elmhurst, IL 60126 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Osaka Univ, Osaka 5600043, Japan. Rice Univ, Houston, TX 77005 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. Univ Virginia, Inst Nucl & Particle Phys, Charlottesville, VA 22901 USA. Univ Sao Paulo, Sao Paulo, Brazil. CNRS, CPP Marseille, F-75700 Paris, France. RP Alexopoulos, T (reprint author), Univ Wisconsin, Madison, WI 53706 USA. RI Moura Santos, Edivaldo/K-5313-2016 OI Moura Santos, Edivaldo/0000-0002-2818-8813 NR 14 TC 13 Z9 13 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 012001 DI 10.1103/PhysRevD.71.012001 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300007 ER PT J AU Atwood, D Soni, A AF Atwood, D Soni, A TI Pathways to a clean gamma(phi(3)): From B to super B factories SO PHYSICAL REVIEW D LA English DT Article ID CP-VIOLATION; WEAK PHASE; DECAYS; GAMMA; MODES AB The implementation of various methods for the determination of gamma through direct CP violation arising in the interference of b-->c and b-->u processes in charged as well as neutral B meson decays are considered. We show that the inclusion of D-0 resulting from D-*0-->D-0+pi(0)(gamma), say, via B-->KD*0 makes a significant difference in the attainable accuracy for gamma. Both exclusive and inclusive decays of the B+/- and B-0 to states containing D-0/(D) over bar (0) followed by both inclusive and exclusive decays of the D-0 are discussed. It is shown that with statistics which might be obtained at B factories (5-10x10(8) B pairs) a 1sigma determination of gamma to approximate to+/-8degrees may be possible, depending on the efficiency of reconstruction, backgrounds, and the details of the decay amplitudes involved. The role of data from a charm factory as well as effects of D-0 mixing are discussed. Extraction of gamma with accuracy that is roughly commensurate with the intrinsic theory error of these methods (i.e., around 0.1%), which is an important goal, will require >10(10) B pairs, namely, a super B factory. C1 Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Brookhaven Natl Lab, Theory Grp, Upton, NY 11973 USA. RP Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. NR 38 TC 12 Z9 12 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 013007 DI 10.1103/PhysRevD.71.013007 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300018 ER PT J AU Berger, EL Nadolsky, PM Olness, FI Pumplin, J AF Berger, EL Nadolsky, PM Olness, FI Pumplin, J TI Light gluino constituents of hadrons and a global analysis of hadron scattering data SO PHYSICAL REVIEW D LA English DT Article ID DEEP-INELASTIC-SCATTERING; DEUTERON STRUCTURE FUNCTIONS; HIGH STATISTICS MEASUREMENT; CURRENT CROSS-SECTIONS; P(P)OVER-BAR COLLISIONS; PROTON COLLISIONS; DELPHI DETECTOR; MUON SCATTERING; BOTTOM SQUARKS; HIGH Q2 AB Light strongly interacting supersymmetric particles may be treated as partonic constituents of nucleons in high energy scattering processes. We construct parton distribution functions for protons in which a light gluino is included along with standard model quark, antiquark, and gluon constituents. A global analysis is performed of a large set of data from deep-inelastic lepton scattering, massive lepton pair and vector boson production, and hadron jet production at large values of transverse momentum. Constraints are obtained on the allowed range of gluino mass as a function of the value of the strong coupling strength alpha(s)(M-Z) determined at the scale of the Z boson mass. We find that gluino masses as small as 10 GeV are admissible provided that alpha(s)(M-Z)greater than or equal to0.12. Current hadron scattering data are insensitive to the presence of gluinos heavier than similar to100-150 GeV. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. So Methodist Univ, Dept Phys, Dallas, TX 75275 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. RP Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. EM berger@anl.gov; nadolsky@hep.anl.gov; olness@smu.edu; pumplin@pa.msu.edu NR 58 TC 37 Z9 37 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 014007 DI 10.1103/PhysRevD.71.014007 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300026 ER PT J AU Birkedal, A Chacko, Z Nomura, Y AF Birkedal, A Chacko, Z Nomura, Y TI Relaxing the upper bound on the mass of the lightest supersymmetric Higgs boson SO PHYSICAL REVIEW D LA English DT Article ID RADIATIVE-CORRECTIONS; STANDARD MODEL; ELECTROWEAK BREAKING; WARPED GEOMETRY; SUPERGRAVITY; UNIFICATION; SPECTRUM; SCALE AB We present a class of supersymmetric models in which the lightest Higgs boson mass can be as large as a few hundred GeV (200similar to300 GeV) while the successful minimal supersymmetric standard model prediction for gauge coupling unification is preserved. The theories are formulated on a 5D warped space truncated by two branes, and a part of the Higgs sector is localized on the infrared brane. The structure of the Higgs sector in the four-dimensional effective theory below the Kaluza-Klein mass scale is essentially that of the next-to-minimal supersymmetric standard model, or related theories. However, large values of the next-to-minimal supersymmetric standard model couplings at the weak scale are now possible as these couplings are required to be perturbative only up to the infrared cutoff scale, which in general can be much lower than the unification scale. This allows the possibility of generating a large quartic coupling in the Higgs potential thereby significantly raising the Higgs boson mass bound. We present two particularly simple models. In the first model, the quark and lepton fields are localized on the ultraviolet brane, where the grand unified symmetry is broken. In the second model, the quark and lepton fields are localized on the infrared brane, and the unified symmetry is broken both on the ultraviolet and infrared branes. Our theories potentially allow the possibility of a significant reduction in the fine-tuning needed for correct electroweak symmetry breaking, although this is somewhat model dependent. C1 Univ Florida, Dept Phys, Gainesville, FL 32611 USA. Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Univ Florida, Dept Phys, Gainesville, FL 32611 USA. OI Nomura, Yasunori/0000-0002-1497-1479 NR 64 TC 55 Z9 55 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 015006 DI 10.1103/PhysRevD.71.015006 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300068 ER PT J AU Burikham, P Figy, T Han, T AF Burikham, P Figy, T Han, T TI TeV-scale string resonances at hadron colliders SO PHYSICAL REVIEW D LA English DT Article ID EXTRA-DIMENSIONS; GAUGE BOSONS; COSMIC NEUTRINOS; HIERARCHY; NUCLEON; MODELS; PHENOMENOLOGY; CONSTRAINTS; MILLIMETER; COLLISIONS AB We construct tree-level four-particle open-string amplitudes relevant to dilepton and diphoton production at hadron colliders. We expand the amplitudes into string resonance (SR) contributions and compare the total cross-section through the first SR with the Z(') search at the Tevatron. We establish a current lower bound based on the CDF Run I results on the string scale to be about 1.1-2.1 TeV, and it can be improved to about 1.5-3 TeV with 2 fb(-1). At the LHC, we investigate the properties of signals induced by string resonances in dilepton and diphoton processes. We demonstrate the unique aspects of SR-induced signals distinguishable from other new physics, such as the angular distributions and forward-backward asymmetry. A 95% C.L. lower bound can be reached at the LHC for M-S>8.2-10 TeV with an integrated luminosity of 300 fb(-1). We emphasize the generic features and profound implications of the amplitude construction. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Fermilab Natl Accelerator Lab, Dept Theoret Phys, Batavia, IL 60510 USA. Acad Sinica, Inst Theoret Phys, Beijing 100080, Peoples R China. RP Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. EM piyabut@physics.wisc.edu; terrance@physics.wisc.edu; than@physics.wisc.edu OI Han, Tao/0000-0002-5543-0716 NR 52 TC 39 Z9 39 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 016005 DI 10.1103/PhysRevD.71.016005 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300083 ER PT J AU Burns, TJ Close, FE Dudek, JJ AF Burns, TJ Close, FE Dudek, JJ TI Pentaquark implications for exotic mesons SO PHYSICAL REVIEW D LA English DT Article ID HYBRID MESONS; LATTICE QCD; ETA-PI; SYSTEMS; MASSES AB If the exotic baryon Theta(+)(1540) is a correlated udud (s) over bar with J(P)=1(+/)2, then there should exist an exotic meson Theta(+) with strangeness +2, J(P)=1(-), mass similar to1.6 GeV, decaying to (K+K0) with width O(10-100) MeV. The pi(1)(1400;1600) may be broad members of 10+/-(10) over bar in such a picture, and it is possible that vector mesons in the 1.4-1.7 GeV mass range are related to this multiplet. We suggest that dynamical correlations may limit the spectrum of J(P(C)) such that the 1(-(+/-)) states are isolated. C1 Univ Oxford, Rudolph Peierls Ctr Theoret Phys, Oxford OX1 3NP, England. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Univ Oxford, Rudolph Peierls Ctr Theoret Phys, 1 Keble Rd, Oxford OX1 3NP, England. EM burns@thphys.ox.ac.uk; f.close@physics.ox.ac.uk; dudek@jlab.org NR 32 TC 16 Z9 16 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 014017 DI 10.1103/PhysRevD.71.014017 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300036 ER PT J AU Carena, M Delgado, A Ponton, E Tait, TMP Wagner, CEM AF Carena, M Delgado, A Ponton, E Tait, TMP Wagner, CEM TI Warped fermions and precision tests SO PHYSICAL REVIEW D LA English DT Article ID RS1 AB We analyze the behavior of standard model matter propagating in a slice of AdS(5) in the presence of infrared-brane kinetic terms. Brane kinetic terms are naturally generated through radiative corrections and can also be present at tree level. The effect of the brane kinetic terms is to expel the heavy Kaluza-Klein (KK) modes from the infrared brane, and hence to reduce their coupling to the localized Higgs field. In a previous work we showed that sizable gauge kinetic terms can allow KK mode masses as low as a few TeV, compatible with present precision measurements. We study here the effect of fermion brane kinetic terms and show that they ameliorate the behavior of the theory for third generation fermions localized away from the infrared brane, reduce the contribution of the third generation quarks to the oblique correction parameters and maintain a good fit to the precision electroweak data for values of the KK masses of the order of the weak scale. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. CERN, Div TH, CH-1211 Geneva, Switzerland. Columbia Univ, Dept Phys, New York, NY 10027 USA. Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Carena, M (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. RI Ponton, Eduardo/I-4125-2013 OI Ponton, Eduardo/0000-0003-3138-1136 NR 47 TC 53 Z9 53 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 015010 DI 10.1103/PhysRevD.71.015010 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300072 ER PT J AU Cheng, HY Chua, CK Soni, A AF Cheng, HY Chua, CK Soni, A TI Final state interactions in hadronic B decays SO PHYSICAL REVIEW D LA English DT Review ID CHIRAL PERTURBATION-THEORY; ENHANCED BRANCHING RATIO; 2-BODY CHARM DECAYS; DIRECT CP VIOLATION; PI-PI DECAYS; QCD FACTORIZATION; HEAVY-QUARK; INTERACTION PHASES; MESON DECAYS; DIAGRAM AB There exist many experimental indications that final-state interactions (FSIs) may play a prominent role not only in charmful B decays but also in charmless B ones. We examine the final-state rescattering effects on the hadronic B decay rates and their impact on direct CP violation. The color-suppressed neutral modes such as B-0-->D(0)pi(0),pi(0)pi(0),rho(0)pi(0),K(0)pi(0) can be substantially enhanced by long-distance rescattering effects. The direct CP-violating partial rate asymmetries in charmless B decays to pipi/piK and rhopi are significantly affected by final-state rescattering, and their signs are generally different from that predicted by the short-distance (SD) approach. For example, direct CP asymmetry in B-0-->rho(0)pi(0) is increased to around 60% due to final-state rescattering effects whereas the short-distance picture gives about 1%. Evidence of direct CP violation in the decay (B) over bar (0)-->K(-)pi(+) is now established, while the combined BABAR and Belle measurements of (B) over bar (0)-->rho(+/-)pi(-/+) imply a 3.6sigma direct CP asymmetry in the rho(+)pi(-) mode. Our predictions for CP violation agree with experiment in both magnitude and sign, whereas the QCD factorization predictions (especially for rho(+)pi(-)) seem to have some difficulty with the data. Direct CP violation in the decay B--->pi(-)pi(0) is very small (less than or similar to1%) in the standard model even after the inclusion of FSIs. Its measurement will provide a nice way to search for new physics as in the standard model QCD penguins cannot contribute (except by isospin violation). Current data on piK modes seem to violate the isospin sum-rule relation, suggesting the presence of electroweak penguin contributions. We have also investigated whether a large transverse polarization in B-->phiK(*) can arise from the final-state rescattering of D-(*)(D) over bar ((*))(s) into phiK(*). While the longitudinal polarization fraction can be reduced significantly from short-distance predictions due to such FSI effects, no sizable perpendicular polarization is found owing mainly to the large cancellations occurring in the processes (B) over bar -->D-s(*)<(D)over bar(>)->phi<(K)over bar>(*) and (B) over bar -->D-s(D) over bar (*)-->phi(K) over bar (*), and this can be understood as a consequence of CP and SU(3) [CPS] symmetry. To fully account for the polarization anomaly (especially the perpendicular polarization) observed in B-->phiK(*), FSI from other states or other mechanism, e.g., the penguin-induced annihilation, may have to be invoked. Our conclusion is that the small value of the longitudinal polarization in VV modes cannot be regarded as a clean signal for new physics. C1 Acad Sinica, Inst Phys, Taipei 115, Taiwan. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Acad Sinica, Inst Phys, Taipei 115, Taiwan. NR 130 TC 238 Z9 239 U1 1 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 014030 DI 10.1103/PhysRevD.71.014030 PG 38 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300049 ER PT J AU Grinstein, B Grossman, Y Ligeti, Z Pirjol, D AF Grinstein, B Grossman, Y Ligeti, Z Pirjol, D TI Photon polarization in B -> X gamma in the standard model SO PHYSICAL REVIEW D LA English DT Article ID COLLINEAR EFFECTIVE THEORY; LIGHT FORM-FACTORS; TO-LEADING ORDER; MESON DECAY; B DECAYS; GAMMA; FACTORIZATION; B->X(S)GAMMA; OPERATORS AB The standard model prediction for the (B) over bar (0)-->X(s,d)gamma decay amplitude with a right-handed photon is believed to be tiny, suppressed by m(s,d)/m(b), compared to the amplitude with a left-handed photon. We show that this suppression is fictitious: In inclusive decays, the ratio of these two amplitudes is only suppressed by g(s)/(4pi), and in exclusive decays by Lambda(QCD)/m(b). The suppression is not stronger in (B) over bar (0)-->X(d)gamma decays than it is in (B) over bar (0)-->X(s)gamma. We estimate that the time dependent CP asymmetries in B-->K(*)gamma, rhogamma, K(S)pi(0)gamma, and pi(+)pi(-)gamma are of order 0.1 and that they have significant uncertainties. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. Boston Univ, Dept Phys, Boston, MA 02215 USA. Harvard Univ, Jefferson Lab Phys, Cambridge, MA 02138 USA. Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. RP Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RI Grinstein, Benjamin/H-5777-2015 OI Grinstein, Benjamin/0000-0003-2447-4756 NR 44 TC 63 Z9 63 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 011504 DI 10.1103/PhysRevD.71.011504 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300004 ER PT J AU Kolb, EW Matarrese, S Notari, A Riotto, A AF Kolb, EW Matarrese, S Notari, A Riotto, A TI Effect of inhomogeneities on the expansion rate of the universe SO PHYSICAL REVIEW D LA English DT Article ID SUPERNOVAE; CONSTANT AB While the expansion rate of a homogeneous isotropic universe is simply proportional to the square-root of the energy density, the expansion rate of an inhomogeneous universe also depends on the nature of the density inhomogeneities. In this paper we calculate to second order in perturbation variables the expansion rate of an inhomogeneous universe and demonstrate corrections to the evolution of the expansion rate. While we find that the mean correction is small, the variance of the correction on the scale of the Hubble radius is sensitive to the physical significance of the unknown spectrum of density perturbations beyond the Hubble radius. C1 Fermilab Natl Accelerator Lab, Ctr Particle Astrophys, Batavia, IL 60510 USA. Univ Chicago, Enrico Fermi Inst, Dept Astron & Astrophys, Chicago, IL 60637 USA. Univ Padua, Dipartimento Fis G Galilei, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Scuola Normale Super Pisa, I-56126 Pisa, Italy. Ist Nazl Fis Nucl, Sez Pisa, Pisa, Italy. RP Kolb, EW (reprint author), Fermilab Natl Accelerator Lab, Ctr Particle Astrophys, POB 500, Batavia, IL 60510 USA. EM rocky@fnal.gov; sabino.matarrese@pd.infn.it; alessio.notari@sns.it; antonio.riotto@pd.infn.it RI Notari, Alessio/A-2309-2017 OI Notari, Alessio/0000-0002-8854-3987 NR 15 TC 117 Z9 117 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 2 AR 023524 DI 10.1103/PhysRevD.71.023524 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893ES UT WOS:000226702700035 ER PT J AU Laiho, J Soni, A AF Laiho, J Soni, A TI Lattice extraction of K ->pi pi amplitudes to next-to-leading order in partially quenched and in full chiral perturbation theory SO PHYSICAL REVIEW D LA English DT Article ID DIRECT CP VIOLATION; FINAL-STATE INTERACTIONS; MATRIX-ELEMENTS; ONE-LOOP; DISPERSION-RELATIONS; STAGGERED FERMIONS; 2-PION AMPLITUDES; I=0 CHANNEL; DECAYS; QCD AB We show that it is possible to construct epsilon'/epsilon to next-to-leading order (NLO) using partially quenched chiral perturbation theory (PQChPT) from amplitudes that are computable on the lattice. We demonstrate that none of the needed amplitudes require 3-momentum on the lattice for either the full theory or the partially quenched theory; nondegenerate quark masses suffice. Furthermore, we find that the electro-weak penguin (DeltaI=3/2 and 1/2) contributions to epsilon'/epsilon in PQChPT can be determined to NLO using only degenerate (m(K)=m(pi)) K-->pi computations without momentum insertion. Issues pertaining to power divergent contributions, originating from mixing with lower dimensional operators, are addressed. Direct calculations of K-->pipi at unphysical kinematics are plagued with enhanced finite volume effects in the (partially) quenched theory, but in simulations when the sea quark mass is equal to the up and down quark mass the enhanced finite volume effects vanish to NLO in PQChPT. In embedding the QCD penguin left-right operator onto PQChPT an ambiguity arises, as first emphasized by Golterman and Pallante. With one version [the "PQS" (patially quenched singlet)] of the QCD penguin, the inputs needed from the lattice for constructing K-->pipi at NLO in PQChPT coincide with those needed for the full theory. Explicit expressions for the finite logarithms emerging from our NLO analysis to the above amplitudes also are given. C1 Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Brookhaven Natl Lab, Theory Grp, Upton, NY 11973 USA. RP Laiho, J (reprint author), Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. EM jlaiho@princeton.edu; soni@bnl.gov NR 55 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 014021 DI 10.1103/PhysRevD.71.014021 PG 28 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300040 ER PT J AU Lewandowski, A AF Lewandowski, A TI Wilsonian renormalization group in the Randall-Sundrum 1 scenario SO PHYSICAL REVIEW D LA English DT Article ID HOLOGRAPHIC RENORMALIZATION; ADS/CFT CORRESPONDENCE; COMPACTIFICATION; STABILIZATION; SPACETIME AB We find renormalization group transformations for the compactified Randall-Sundrum scenario by integrating out an infinitesimal slice of ultraviolet degrees of freedom near the Planck brane. Under these transformations the coefficients of operators on the Planck brane experience RG evolution. The extra-dimensional radius also scales, flowing to zero in the IR. We find an attractive fixed point in the context of a bulk scalar field theory. Calculations are simplified in the low energy effective theory as we demonstrate with the computation of a loop diagram. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. NR 43 TC 7 Z9 7 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 2 AR 024006 DI 10.1103/PhysRevD.71.024006 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893ES UT WOS:000226702700044 ER PT J AU Martin, SP AF Martin, SP TI Strong and Yukawa two-loop contributions to Higgs scalar boson self-energies and pole masses in supersymmetry SO PHYSICAL REVIEW D LA English DT Article ID EXPLICIT CP VIOLATION; RENORMALIZATION-GROUP EQUATIONS; STANDARD-MODEL; RADIATIVE-CORRECTIONS; DIFFERENTIAL-EQUATIONS; NUMERICAL EVALUATION; DIMENSIONAL REDUCTION; PROPAGATOR INTEGRALS; SYMMETRY-BREAKING; MASTER INTEGRALS AB I present results for the two-loop self-energy functions for neutral and charged Higgs scalar bosons in minimal supersymmetry. The contributions given here include all terms involving the QCD coupling, and those following from Feynman diagrams involving Yukawa couplings and scalar interactions that do not vanish as the electroweak gauge couplings are turned off. The impact of these contributions on the computation of pole masses of the neutral and charged Higgs scalar bosons is studied in a few examples. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Martin, SP (reprint author), No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. NR 87 TC 55 Z9 55 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 016012 DI 10.1103/PhysRevD.71.016012 PG 23 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300090 ER PT J AU Sterman, G Vogelsang, W AF Sterman, G Vogelsang, W TI Recoil and power corrections in high-x(T) direct photon production SO PHYSICAL REVIEW D LA English DT Article ID SMALL TRANSVERSE-MOMENTUM; ELECTROWEAK BOSON PRODUCTION; HIGH-ENERGY FACTORIZATION; HEAVY FLAVOR PRODUCTION; TO-LEADING-ORDER; CROSS-SECTIONS; PARTON DISTRIBUTIONS; HADRON COLLIDERS; HARD PROCESSES; HIGGS-BOSON AB We study a class of nonperturbative corrections to single-inclusive photon cross sections at measured transverse momentum p(T), in the large-x(T) limit. We develop an extension of the joint (threshold and transverse momentum) resummation formalism, appropriate for large x(T), in which there are no kinematic singularities associated with recoil, and for which matching to fixed-order and to threshold resummation at next-to-leading logarithm (NLL) is straightforward. Beyond NLL, we find contributions that can be attributed to recoil from initial-state radiation. Associated power corrections occur as inverse powers of p(T)(2) and are identified from the infrared structure of integrals over the running coupling. They have significant energy-dependence and decrease from typical fixed-target to collider energies. Energy conservation, which is incorporated into joint resummation, moderates the effects of perturbative recoil and power corrections for large x(T). C1 SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Sterman, G (reprint author), SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. NR 96 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 014013 DI 10.1103/PhysRevD.71.014013 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300032 ER PT J AU Young, RD Leinweber, DB Thomas, AW AF Young, RD Leinweber, DB Thomas, AW TI Leading quenching effects in the proton magnetic moment SO PHYSICAL REVIEW D LA English DT Article ID ELECTROMAGNETIC FORM-FACTORS; CHIRAL PERTURBATION-THEORY; NONPERTURBATIVE O(A) IMPROVEMENT; LATTICE QCD; FLIC FERMIONS; GAUGE-THEORIES; OCTET BARYONS; SYMMETRY; NUCLEON; EXTRAPOLATIONS AB We present the first investigation of the extrapolation of quenched nucleon magnetic moments in quenched chiral effective field theory. We utilize established techniques in finite-range regularization and incorporate finite-volume corrections to the relevant loop integrals. Finally, the contributions of dynamical sea quarks to the proton moment are estimated using a recently discovered phenomenological link between quenched and physical QCD. C1 Univ Adelaide, Special Res Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia. Univ Adelaide, Dept Phys & Math Phys, Adelaide, SA 5005, Australia. Jefferson Lab, Newport News, VA 23606 USA. RP Young, RD (reprint author), Univ Adelaide, Special Res Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia. RI Thomas, Anthony/G-4194-2012; Young, Ross/H-8207-2012; Leinweber, Derek/J-6705-2013 OI Thomas, Anthony/0000-0003-0026-499X; Leinweber, Derek/0000-0002-4745-6027 NR 60 TC 52 Z9 52 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN PY 2005 VL 71 IS 1 AR 014001 DI 10.1103/PhysRevD.71.014001 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 893EO UT WOS:000226702300020 ER PT J AU Benczik, IJ Neufeld, Z Tel, T AF Benczik, IJ Neufeld, Z Tel, T TI Multifractal spectra of chemical fields in fluid flows SO PHYSICAL REVIEW E LA English DT Article ID SIGN-SINGULAR MEASURES; OPEN CHAOTIC FLOWS; ADVECTION; TURBULENCE AB In the filamental phase of reactions embedded in fluid flows, where the concentration distribution is strongly fluctuating, we show that a chemical measure can be defined based on the absolute value of the concentration gradients. We express the generalized dimensions in terms of the roughness exponents of the structure functions as well as of the cancellation exponents of the chemical concentration. This measure is of basically different character than the natural distribution of the passive advection. It is similar to the SRB measures of dissipative systems, although the advection problem is area preserving. This approach is shown to be a useful tool in analyzing sea surface temperature anomalies. C1 Eotvos Lorand Univ, Dept Theoret Phys, H-1518 Budapest, Hungary. Max Planck Inst Phys Komplexer Syst, D-01187 Dresden, Germany. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Eotvos Lorand Univ, Dept Theoret Phys, H-1518 Budapest, Hungary. RI Neufeld, Zoltan/C-3008-2011 NR 26 TC 7 Z9 7 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD JAN PY 2005 VL 71 IS 1 AR 016208 DI 10.1103/PhysRevE.71.016208 PN 2 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 903XR UT WOS:000227459400061 PM 15697699 ER PT J AU Hansen, SB Fournier, KB Faenov, AY Magunov, AI Pikuz, TA Skobelev, IY Fukuda, Y Akahane, Y Aoyama, M Inoue, N Ueda, H Yamakawa, K AF Hansen, SB Fournier, KB Faenov, AY Magunov, AI Pikuz, TA Skobelev, IY Fukuda, Y Akahane, Y Aoyama, M Inoue, N Ueda, H Yamakawa, K TI Measurement of 21-nl ' x-ray transitions from approximate to I mu m Kr clusters irradiated by high-intensity femtosecond laser pulses SO PHYSICAL REVIEW E LA English DT Article ID PLASMAS; TARGETS; CRYSTALS; SPECTROSCOPY; GENERATION; SYSTEM; IONS; MICA; IRON AB X-ray line emission from 21-nl' transitions in Ne-like Kr and nearby ions has been observed from approximate to1 mum Kr clusters irradiated by fs-scale laser pulses at the JAERI facility in Kyoto, Japan. The incident laser intensity reached 10(19) W/cm(2), with pulse energies from 50 to 300 mJ and pulse durations from 30 to 500 fs. The dependence of the x-ray spectral features and intensity on the incident laser intensity is rather weak, indicating that the 1-2 ps cluster lifetimes limit the number of ions beyond Ne-like Kr that can be produced by collisional ionization. Lines from F- to Al-like Kr emitted from the cluster plasmas have been identified using data from the relativistic multiconfiguration flexible atomic code. A collisional-radiative model based on these data has been constructed and used to determine that the cluster plasma has electron densities near 10(22) cm(-3), temperatures of a few hundred eV, and hot electron fractions of a few percent. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. VNIIFTRI, Multicharged Ions Spectra Data Ctr, Mendeleyevsk 141570, Moscow Region, Russia. Japan Atom Energy Res Inst, Adv Photon Res Ctr, Kizu, Kyoto 6190215, Japan. RP Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 38 TC 13 Z9 13 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD JAN PY 2005 VL 71 IS 1 AR 016408 DI 10.1103/PhysRevE.71.016408 PN 2 PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 903XR UT WOS:000227459400098 PM 15697736 ER PT J AU Mazevet, S Desjarlais, MP Collins, LA Kress, JD Magee, NH AF Mazevet, S Desjarlais, MP Collins, LA Kress, JD Magee, NH TI Simulations of the optical properties of warm dense aluminum SO PHYSICAL REVIEW E LA English DT Article ID TOTAL-ENERGY CALCULATIONS; AUGMENTED-WAVE METHOD; GPA 1.4 MBAR; MOLECULAR-DYNAMICS; ELECTRICAL-CONDUCTIVITY; LIQUID DEUTERIUM; ULTRASOFT PSEUDOPOTENTIALS; HOT ALUMINUM; BASIS-SET; HYDROGEN AB Using quantum molecular dynamics simulations, we show that the optical properties of aluminum change drastically along the nonmetal metal transition observed experimentally. As the density increases and the many-body effects become important, the optical response gradually evolves from the one characteristic of an atomic fluid to the one of a simple metal. We show that quantum molecular dynamics combined with the Kubo-Greenwood formulation naturally embodies the two limits and provides a powerful too] to calculate and benchmark the optical properties of various systems as they evolve into the warm dense matter regime. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Sandia Natl Labs, Pulsed Power Sci Ctr, Albuquerque, NM 87185 USA. RP Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 67 TC 92 Z9 92 U1 0 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD JAN PY 2005 VL 71 IS 1 AR 016409 DI 10.1103/PhysRevE.71.016409 PN 2 PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 903XR UT WOS:000227459400099 PM 15697737 ER PT J AU Sanchez, R Carreras, BA van Milligen, BP AF Sanchez, R Carreras, BA van Milligen, BP TI Fluid limit of nonintegrable continuous-time random walks in terms of fractional differential equations SO PHYSICAL REVIEW E LA English DT Article ID SELF-ORGANIZED CRITICALITY; ANOMALOUS TRANSPORT; DIFFUSION; DYNAMICS; MODEL; PARADIGM; CONFINEMENT; AVALANCHES; TURBULENCE; CALCULUS AB The fluid limit of a recently introduced family of nonintegrable (nonlinear) continuous-time random walks is derived in terms of fractional differential equations. In this limit, it is shown that the formalism allows for the modeling of the interaction between multiple transport mechanisms with not only disparate spatial scales but also different temporal scales. For this reason, the resulting fluid equations may find application in the study of a large number of nonlinear multiscale transport problems, ranging from the study of self-organized criticality to the modeling of turbulent transport in fluids and plasmas. C1 Univ Carlos III Madrid, Dept Fis, Madrid 28911, Spain. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37831 USA. Asoc EURATOM CIEMAT, Lab Nacl Fus, Madrid 28040, Spain. RP Univ Carlos III Madrid, Dept Fis, Madrid 28911, Spain. EM rsanchez@fis.uc3m.es RI Sanchez, Raul/C-2328-2008; van Milligen, Boudewijn/H-5121-2015 OI van Milligen, Boudewijn/0000-0001-5344-6274 NR 64 TC 34 Z9 34 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD JAN PY 2005 VL 71 IS 1 AR 011111 DI 10.1103/PhysRevE.71.011111 PN 1 PG 10 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 903XP UT WOS:000227459200016 PM 15697584 ER PT J AU Sapozhnikov, MV Peleg, A Meerson, B Aranson, IS Kohlstedt, KL AF Sapozhnikov, MV Peleg, A Meerson, B Aranson, IS Kohlstedt, KL TI Far-from-equilibrium Ostwald ripening in electrostatically driven granular powders SO PHYSICAL REVIEW E LA English DT Article ID SUPERSATURATED SOLID SOLUTIONS; BISTABLE SYSTEMS; SELECTION; STABILITY; KINETICS AB We report an experimental study of cluster size distributions in electrostatically driven granular submonolayers. The cluster size distribution in this far-from-equilibrium process exhibits dynamic scaling behavior characteristic of the (nearly equilibrium) Ostwald ripening, controlled by the attachment and detachment of the "gas" particles. The scaled size distribution, however, is different from the classical Wagner distribution obtained in the limit of a vanishingly small area fraction of the clusters. A much better agreement is found with the theory of Conti et al. [Phys. Rev. E 65, 046117 (2002)] which accounts for the cluster merger. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Russian Acad Sci, Inst Phys Microstruct, Nizhnii Novgorod 603600, Russia. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Aranson, Igor/I-4060-2013 NR 26 TC 7 Z9 7 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD JAN PY 2005 VL 71 IS 1 AR 011307 DI 10.1103/PhysRevE.71.011307 PN 1 PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 903XP UT WOS:000227459200027 PM 15697595 ER PT J AU Anderson, SG Musumeci, P Rosenzweig, JB Brown, WJ England, RJ Ferrario, M Jacob, JS Thompson, MC Travish, G Tremaine, AM Yoder, R AF Anderson, SG Musumeci, P Rosenzweig, JB Brown, WJ England, RJ Ferrario, M Jacob, JS Thompson, MC Travish, G Tremaine, AM Yoder, R TI Velocity bunching of high-brightness electron beams SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID THOMSON-SCATTERING; SUBPICOSECOND ELECTRON; PHOTOINJECTORS; COMPRESSION; RADIATION; DYNAMICS; PULSES AB Velocity bunching has been recently proposed as a tool for compressing electron beam pulses in modern high brightness photoinjector sources. This tool is familiar from earlier schemes implemented for bunching dc electron sources, but presents peculiar challenges when applied to high current, low emittance beams from photoinjectors. The main difficulty foreseen is control of emittance oscillations in the beam in this scheme, which can be naturally considered as an extension of the emittance compensation process at moderate energies. This paper presents two scenarios in which velocity bunching, combined with emittance control, is to play a role in nascent projects. The first is termed ballistic bunching, where the changing of relative particle velocities and positions occur in distinct regions, a short high gradient linac, and a drift length. This scenario is discussed in the context of the proposed ORION photoinjector. Simulations are used to explore the relationship between the degree of bunching, and the emittance compensation process. Experimental measurements performed at the UCLA Neptune Laboratory of the surprisingly robust bunching process, as well as accompanying deleterious transverse effects, are presented. An unanticipated mechanism for emittance growth in bends for highly momentum chirped beam was identified and studied in these experiments. The second scenario may be designated as phase space rotation, and corresponds closely to the recent proposal of Ferrario and Serafini. Its implementation for the compression of the electron beam pulse length in the PLEIADES inverse Compton scattering (ICS) experiment at LLNL is discussed. It is shown in simulations that optimum compression may be obtained by manipulation of the phases in low gradient traveling wave accelerator sections. Measurements of the bunching and emittance control achieved in such an implementation at PLEIADES, as well as aspects of the use of velocity-bunched beam directly in ICS experiments, are presented. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. RP Anderson, SG (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave, Livermore, CA 94550 USA. EM anderson131@llnl.gov RI Travish, Gil/H-4937-2011 OI Travish, Gil/0000-0002-4787-0949 NR 39 TC 35 Z9 35 U1 2 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD JAN PY 2005 VL 8 IS 1 AR 014401 DI 10.1103/PhysRevSTAB.8.014401 PG 22 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 895XY UT WOS:000226899000008 ER PT J AU Bieniosek, FM Celata, CM Henestroza, E Kwan, JW Prost, L Seidl, PA Friedman, A Grote, DP Lund, SM Haber, I AF Bieniosek, FM Celata, CM Henestroza, E Kwan, JW Prost, L Seidl, PA Friedman, A Grote, DP Lund, SM Haber, I TI 2-MV electrostatic quadrupole injector for heavy-ion fusion SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID 2 MV INJECTOR; ACCELERATOR; SIMULATIONS; DIODE; BEAMS; HIF AB High current and low emittance are principal requirements for heavy-ion injection into a linac driver for inertial fusion energy. An electrostatic quadrupole injector is capable of providing these high charge density and low emittance beams. We have modified the existing 2-MV injector to reduce beam emittance and to double the pulse length. We characterize the beam delivered by the modified injector to the High Current Transport Experiment and the effects of finite rise time of the extraction voltage pulse in the diode on the beam head. We demonstrate techniques for mitigating aberrations and reducing beam emittance growth in the injector. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Heavy Ion Fus Virtual Natl Lab, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Heavy Ion Fus Virtual Natl Lab, Livermore, CA 94550 USA. Univ Maryland, Inst Res Elect & Appl Phys, College Pk, MD 20742 USA. RP Bieniosek, FM (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 22 TC 1 Z9 1 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD JAN PY 2005 VL 8 IS 1 AR 010101 DI 10.1103/PhysRevSTAB.8010101 PG 13 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 895XY UT WOS:000226899000001 ER PT J AU Luo, Y Cameron, P Della Penna, A Laster, J Lee, R Marusic, A Pilat, F Roser, T Trbojevic, D Wei, J AF Luo, Y Cameron, P Della Penna, A Laster, J Lee, R Marusic, A Pilat, F Roser, T Trbojevic, D Wei, J TI Measurement of global betatron coupling with skew quadrupole modulation SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB Measurement of the residual betatron coupling with skew quadrupole modulation is a new diagnostics technique. It was developed and tested at the Relativistic Heavy Ion Collider (RHIC) as a promising method for measuring coupling on the ramp. By modulating the strengths of skew quadrupole families, the two tunes' responses are precisely measured with the phase lock loop system. The projection ratio of the residual coupling coefficient onto the coupling modulation direction can be determined. In this article, the analytical solution to the skew quadrupole modulation is given. Dedicated beam studies were carried out in RHIC Run'04 and the results are presented. The ability to measure coupling on the ramp opens the possibility of continuously correcting coupling during acceleration. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Luo, Y (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. EM yluo@bnl.gov RI Marusic, Ana/E-7683-2013 OI Marusic, Ana/0000-0001-6272-0917 NR 9 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD JAN PY 2005 VL 8 IS 1 AR 014001 DI 10.1103/PhysRevSTAB.8.014001 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 895XY UT WOS:000226899000005 ER PT J AU Sekutowicz, J Bogacz, SA Douglas, D Kneisel, P Williams, GP Ferrario, M Ben- Zvi, I Rose, J Smedley, J Srinivasan-Rao, T Serafini, L Moller, WD Petersen, B Proch, D Simrock, S Colestock, P Rosenzweig, JB AF Sekutowicz, J Bogacz, SA Douglas, D Kneisel, P Williams, GP Ferrario, M Ben- Zvi, I Rose, J Smedley, J Srinivasan-Rao, T Serafini, L Moller, WD Petersen, B Proch, D Simrock, S Colestock, P Rosenzweig, JB TI Proposed continuous wave energy recovery operation of an x-ray free electron laser SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID PHOTOINJECTORS AB Commissioning of two large coherent light facilities (XFELs) at SLAC and DESY should begin in 2008 and 2011, respectively. In this paper we look further into the future, hoping to answer, in a very preliminary way, two questions. First: What will the next generation of XFEL facilities look like? Believing that superconducting technology offers advantages such as high quality beams with highly populated bunches, the possibility of energy recovery and higher overall efficiency than warm technology, we focus this preliminary study on the superconducting option. From this belief the second question arises: What modifications in superconducting technology and in the machine design are needed, as compared to the present DESY XFEL, and what kind of research and development program should be proposed to arrive in the next few years at a technically feasible solution with even higher brilliance and increased overall conversion of ac power to photon beam power? In this paper we will very often refer to and profit from the DESY XFEL design, acknowledging its many technically innovative solutions. C1 Thomas Jefferson Natl Accelerator Facil, JLab, Newport News, VA 23606 USA. Ist Nazl Fis Nucl, I-00044 Frascati, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. Ist Nazl Fis Nucl, I-20133 Milan, Italy. DESY, D-22603 Hamburg, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. RP Sekutowicz, J (reprint author), Thomas Jefferson Natl Accelerator Facil, JLab, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 26 TC 17 Z9 17 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD JAN PY 2005 VL 8 IS 1 AR 010701 DI 10.1103/PhysRevSTAB.8.010701 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 895XY UT WOS:000226899000002 ER PT J AU Venturini, M Warnock, R Ruth, R Ellison, JA AF Venturini, M Warnock, R Ruth, R Ellison, JA TI Coherent synchrotron radiation and bunch stability in a compact storage ring SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID EQUATION; SPACE AB We examine the effect of the collective force due to coherent synchrotron radiation (CSR) in an electron storage ring with small bending radius. In a computation based on time-domain integration of the nonlinear Vlasov equation, we find the threshold current for a longitudinal microwave instability induced by CSR alone. The model accounts for suppression of radiation at long wavelengths due to shielding by the vacuum chamber. In a calculation just above threshold, small ripples in the charge distribution build up over a fraction of a synchrotron period, but then die out to yield a relatively smooth but altered distribution with eventual oscillations in bunch length. The instability evolves from small noise on an initial smooth bunch of rms length much greater than the shielding cutoff. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. RP Venturini, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM mventurini@lbl.gov; warnock@slac.stanford.edu; rruth@slac.stanford.edu; ellison@math.unm.edu NR 44 TC 25 Z9 25 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD JAN PY 2005 VL 8 IS 1 AR 014202 DI 10.1103/PhysRevSTAB.8.014202 PG 15 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 895XY UT WOS:000226899000007 ER PT J AU Warnock, R Ruth, R Venturini, M Ellison, JA AF Warnock, R Ruth, R Venturini, M Ellison, JA TI Impedance description of coherent synchrotron radiation with account of bunch deformation SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB We are concerned with coherent longitudinal motion in a storage ring, especially with situations in which coherent synchrotron radiation (CSR) can influence stability of the beam. The collective force from CSR is usually described by an impedance or a wake function in such a way that the force depends only on the charge distribution at the present time. This description is exact only for a rigid bunch, since causality demands that the force depend on the prior history of the bunch. We show how to treat a deforming bunch by applying the "complete impedance'' Z(n, omega) a function of wave number and frequency. We derive this impedance and study its analytic properties for a special model: radiation from circular orbits shielded by parallel plates representing the metallic vacuum chamber. We analyze the corresponding collective force, obtaining the usual formula as a first approximation, plus easily computed corrections that depend on present and prior values of the time derivative of the charge density. In related papers we have applied these results in numerical simulations of instabilities induced by CSR. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. RP Warnock, R (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM warnock@slac.stanford.edu; rruth@slac.stanford.edu; mventurini@lbl.gov; ellison@math.unm.edu NR 16 TC 6 Z9 6 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD JAN PY 2005 VL 8 IS 1 AR 014402 DI 10.1103/PhysRevSTAB.8.014402 PG 11 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 895XY UT WOS:000226899000009 ER PT S AU Pocha, M Bond, T Welty, R Vernon, S Kallman, J Behymer, E AF Pocha, M Bond, T Welty, R Vernon, S Kallman, J Behymer, E BE Osinski, M Henneberger, F Amano, H TI Gain lever characterization in monolithically integrated diode lasers SO Physics and Simulation of Optoelectronic Devices XIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Physics and Simulation of Optoelectronic Devices XIII CY JAN 24-27, 2005 CL San Jose, CA SP SPIE DE gain lever; laser diode; simulation; measured; InGaAs DQW ID QUANTUM-WELL LASERS; MQW LASERS; MODULATION; NOISE AB Gain Lever, an effect for enhancing amplitude modulation (AM) efficiency in multisection laser diodes', has been characterized in InGaAs DQW edge emitting lasers that are integrated with passive waveguides. Specifically designed structures which give a range of split ratios from 1: 1 to 9:1 have been fabricated and measured to fully characterize the parameter space for operation in the gain lever mode. Additionally the experimental results are compared to a hybrid 3D simulation involving effective index method (EIM) reduction to 2-D. Gains greater than 6 dB in the AM efficiency can be achieved within the appropriate operating range, but this gain drops rapidly as the parameter range is exceeded. High speed RF modulation with significant gain is, in principle, possible if proper biasing and modulation conditions are used. This phenomenon can also be useful for high-speed digital information transmission. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Pocha, M (reprint author), Lawrence Livermore Natl Lab, POB 808,L-222, Livermore, CA 94551 USA. RI Nikolic, Rebecca/C-3618-2009 NR 13 TC 2 Z9 2 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5696-9 J9 P SOC PHOTO-OPT INS PY 2005 VL 5722 BP 288 EP 298 DI 10.1117/12.590904 PG 11 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics; Physics, Applied SC Engineering; Instruments & Instrumentation; Optics; Physics GA BCL18 UT WOS:000229828500030 ER PT S AU Winske, D Yin, L AF Winske, D Yin, L BE Li, G Zank, GP Russell, CT TI Issues tor hybrid simulations of collisionless shocks SO PHYSICS OF COLLISIONLESS SHOCKS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 4th Annual IGPP International Astrophysics Conference CY FEB 26-MAR 03, 2005 CL Palm Springs, CA SP IGPP, Univ Calif, Riverside, IGPP, Univ Calif, Los Angeles, IGPP, Los Alamos Natl Lab ID SLOW-MODE SHOCKS; MAGNETIC RECONNECTION; PRESSURE TENSOR; MAGNETOTAIL; PHYSICS AB We discuss ways in which well-known hybrid simulation methods can be extended to address ongoing issues related to the structure and properties of collisionless shocks. Focusing primarily on slow-mode shocks, we discuss how the basic physics model for the electrons can be enhanced and how kinetic models can be embedded in more global calculations. C1 Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Winske, D (reprint author), Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0268-X J9 AIP CONF PROC PY 2005 VL 781 BP 50 EP 55 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA BDG24 UT WOS:000233337400008 ER PT B AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Wakes and Impedances SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID COUPLING IMPEDANCE; HIGH-FREQUENCY; BEAM PIPE; LONGITUDINAL IMPEDANCE; ENERGY-LOSS; PARTICLES; DIFFRACTION; IONIZATION; LOSSES; MODEL C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 53 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 1 EP 36 D2 10.1142/9789812703392 PG 36 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700002 ER PT B AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Physics of Intensity Dependent Beam Instabilities Preface SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Editorial Material; Book Chapter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP VII EP IX D2 10.1142/9789812703392 PG 3 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700001 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Potential-Well Distortion SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 29 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 37 EP 87 DI 10.1142/9789812703392_0002 D2 10.1142/9789812703392 PG 51 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700003 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Betatron Tune Shifts SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID ELLIPTIC VACUUM CHAMBERS; BEAMS C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 89 EP 132 DI 10.1142/9789812703392_0003 D2 10.1142/9789812703392 PG 44 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700004 ER PT B AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Envelope Equation SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID SPACE-CHARGE; EMITTANCE; ENERGY; BEAMS C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 133 EP 158 DI 10.1142/9789812703392_0004 D2 10.1142/9789812703392 PG 26 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700005 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Longitudinal Microwave Instability for Coasting Beams SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID PARTICLE ACCELERATORS; STORAGE RING C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 159 EP 192 DI 10.1142/9789812703392_0005 D2 10.1142/9789812703392 PG 34 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700006 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Longitudinal Microwave Instability for Short Bunches SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID BEAMS C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 193 EP 239 DI 10.1142/9789812703392_0006 D2 10.1142/9789812703392 PG 47 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700007 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Beam-Loading and Robinson's Instability SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID COMPENSATION C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 241 EP 300 DI 10.1142/9789812703392_0007 D2 10.1142/9789812703392 PG 60 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700008 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Longitudinal Coupled-Bunch Instabilities SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID DOUBLE-RF SYSTEM; PARTICLE MOTION; BEAMS C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 301 EP 357 DI 10.1142/9789812703392_0008 D2 10.1142/9789812703392 PG 57 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700009 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Transverse Instabilities SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID SYNCHROTRON C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 359 EP 391 DI 10.1142/9789812703392_0009 D2 10.1142/9789812703392 PG 33 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700010 ER PT B AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Transverse Coupled-Bunch Instabilities SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 393 EP 444 DI 10.1142/9789812703392_0010 D2 10.1142/9789812703392 PG 52 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700011 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Mode-Coupling Instabilities SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 445 EP 472 DI 10.1142/9789812703392_0011 D2 10.1142/9789812703392 PG 28 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700012 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Head-Tail Instabilities SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 473 EP 497 DI 10.1142/9789812703392_0012 D2 10.1142/9789812703392 PG 25 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700013 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Landau Damping SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 499 EP 556 DI 10.1142/9789812703392_0013 D2 10.1142/9789812703392 PG 58 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700014 ER PT B AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Beam Breakup SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 557 EP 607 DI 10.1142/9789812703392_0014 D2 10.1142/9789812703392 PG 51 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700015 ER PT B AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Two-Stream Instabilities SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter ID BEAM-ION INSTABILITY; RADIATION; MOLECULES; ATOMS C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 63 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 609 EP 690 DI 10.1142/9789812703392_0015 D2 10.1142/9789812703392 PG 82 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700016 ER PT J AU Ng, KY AF Ng, K. Y. BA Ng, KY BF Ng, KY TI Instabilities Near and Across Transition SO PHYSICS OF INTENSITY DEPENDENT BEAM INSTABILITIES LA English DT Article; Book Chapter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, KY (reprint author), Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. NR 38 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81270-339-2 PY 2005 BP 691 EP 770 DI 10.1142/9789812703392_0016 D2 10.1142/9789812703392 PG 80 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BZC73 UT WOS:000301124700017 ER PT J AU Bogolyubov, NN Prykarpatsky, YA Samoilenko, AM Prykarpatsky, AK AF Bogolyubov, NN Prykarpatsky, YA Samoilenko, AM Prykarpatsky, AK TI Generalized de Rham-Hodge theory of multidimensional Delsarte transmutations of differential operators and its applications for nonlinear dynamic systems SO PHYSICS OF PARTICLES AND NUCLEI LA English DT Article; Proceedings Paper CT Bogolyubov Conference on Modern Problems of Mathematical and Theoretical Physics CY SEP 13-17, 2004 CL Kiev, UKRAINE SP UNESCO, Reg Bureau Sci Europe, Russian Fdn Basic Res, JINR Special Heisenberg-Landau & Bogolyubov Infeld Programs ID DARBOUX TRANSFORMATIONS; EQUATIONS AB The differential-geometric and topological structure of Delsarte transmutation operators, and the Gelfand-Levitan-Marchenko-type equations associated with them, are studied by using a generalized de Rham-Hodge differential complex. The relationships to spectral theory and special Berezansky-type congruence properties of Delsarte transmuted operators are stated. Some applications to multidimensional differential operators, and their multidimensional affine extensions related to integrable multidimensional dynamic systems, are discussed. C1 VA Steklov Math Inst, Moscow 117960, Russia. Natl Acad Sci Ukraine, Inst Math, Kiev, Ukraine. Brookhaven Natl Lab, CDIC, Upton, NY 11973 USA. AGH Univ Sci & Technol, Dept Appl Math, PL-30059 Krakow, Poland. RP Bogolyubov, NN (reprint author), VA Steklov Math Inst, Moscow 117960, Russia. NR 42 TC 0 Z9 0 U1 0 U2 0 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 1063-7796 J9 PHYS PART NUCLEI+ JI Phys. Part. Nuclei PY 2005 VL 36 SU 1 BP S111 EP S122 PG 12 WC Physics, Particles & Fields SC Physics GA 981IP UT WOS:000233082100020 ER PT J AU Apruzese, JP Clark, RW Kepple, PC Davis, J Sanford, TWL Nash, TJ Mock, RC Peterson, DL AF Apruzese, JP Clark, RW Kepple, PC Davis, J Sanford, TWL Nash, TJ Mock, RC Peterson, DL TI Diagnosing dynamic hohlraums with tracer absorption line spectroscopy SO PHYSICS OF PLASMAS LA English DT Article ID X-RAY SOURCE; ICF EXPERIMENTS; DENSE-PLASMAS; RADIATION; ALUMINUM; PHYSICS; DRIVEN; ARGON; POWER AB In recent dynamic hohlraum experiments on the Z facility, Al and MgF2 tracer layers were embedded in cylindrical CH2 foam targets to provide K-shell lines in the keV spectral region for diagnosing the conditions of the interior hohlraum plasma. The position of the tracers was varied: sometimes they were placed 2 mm from the ends of the foam cylinder and sometimes at the ends of the cylinder. Also varied was the composition of the tracers in the sense that pure Al layers, pure MgF2 layers, or mixtures of the elements were employed on various shots. Time-resolved K-shell spectra of both Al and Mg show mostly absorption lines. These data can be analyzed with detailed configuration atomic models of carbon, aluminum, and magnesium in which spectra are calculated by solving the radiation transport equation for as many as 4100 frequencies. We report results from shot Z1022 to illustrate the basic radiation physics and the capabilities as well as limitations of this diagnostic method. (C) 2005 American Institute of Physics. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Apruzese, JP (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 26 TC 9 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 2005 VL 12 IS 1 AR 012705 DI 10.1063/1.1834917 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 895LN UT WOS:000226864500045 ER PT J AU Catto, PJ Simakov, AN AF Catto, PJ Simakov, AN TI Evaluation of the neoclassical radial electric field in a collisional tokamak SO PHYSICS OF PLASMAS LA English DT Article ID TRANSPORT-EQUATIONS; TOROIDAL ROTATION; MAGNETIC-FIELD; ION-TRANSPORT; PLASMA; MOMENTUM; SYSTEMS; EDGE AB The neoclassical electric field in a tokamak is determined by the conservation of toroidal angular momentum. In the steady state in the absence of momentum sources and sinks it is explicitly evaluated by the condition that radial flux of toroidal angular momentum vanishes. For a collisional or Pfirsch-Schluter short mean-free path ordering with subsonic plasma flows we find that there are two limiting cases of interest. The first is the simpler case of a strongly up-down asymmetric tokamak for which the lowest order gyroviscosity does not vanish and must be balanced by the leading order collisional viscosity in order to determine the radial electric field. The second case is the more complicated case of an up-down symmetric tokamak for which the gyroviscosity must be evaluated to higher order and again balanced by the lowest order collisional viscosity to determine the radial electric field. In general, both the lowest and the next order contributions from the gyroviscosity must be retained. (C) 2005 American Institute of Physics. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Catto, PJ (reprint author), MIT, Plasma Sci & Fus Ctr, 167 Albany St, Cambridge, MA 02139 USA. NR 26 TC 41 Z9 41 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 2005 VL 12 IS 1 AR 012501 DI 10.1063/1.1819372 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 895LN UT WOS:000226864500033 ER PT J AU Ji, HT Fox, W Pace, D AF Ji, HT Fox, W Pace, D TI Study of small-amplitude magnetohydrodynamic surface waves on liquid metal SO PHYSICS OF PLASMAS LA English DT Article ID MAGNETIC-FIELD; X-RAY; INSTABILITIES; CYLINDER; GALLIUM; FUSION; FORCE AB Magnetohydrodynamic (MHD) surface waves on liquid metal are studied theoretically and experimentally in the small magnetic Reynolds number limit. A linear dispersion relation is derived when a horizontal magnetic field and a horizontal electric current is imposed. Waves always damp in the deep liquid limit with a magnetic field parallel to the propagation direction. When the magnetic field is weak, waves are weakly damped and the real part of the dispersion is unaffected, while in the opposite limit waves are strongly damped with shortened wavelengths. In a table-top experiment, planar MHD surface waves on liquid gallium are studied in detail in the regime of weak magnetic field and deep liquid. A noninvasive diagnostic accurately measures surface waves at multiple locations by reflecting an array of lasers off the surface onto a screen, which is recorded by an intensified-CCD (charge-coupled device) camera. The measured dispersion relation is consistent with the linear theory with a reduced surface tension likely due to surface oxidation. In excellent agreement with linear theory, it is observed that surface waves are damped only when a horizontal magnetic field is imposed parallel to the propagation direction. No damping is observed under a perpendicular magnetic field. The existence of strong wave damping even without magnetic field suggests the importance of the surface oxide layer. Implications to the liquid metal wall concept in fusion reactors, especially on the wave damping and a Rayleigh-Taylor instability when the Lorentz force is used to support liquid metal layer against gravity, are discussed. (C) 2005 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Texas, Inst Fus Studies, Austin, TX 78712 USA. RP Ji, HT (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. EM hji@pppl.gov NR 29 TC 9 Z9 9 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 2005 VL 12 IS 1 AR 012102 DI 10.1063/1.1822933 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 895LN UT WOS:000226864500004 ER PT J AU Lemke, RW Bailey, JE Chandler, GA Nash, TJ Slutz, SA Mehlhorn, TA AF Lemke, RW Bailey, JE Chandler, GA Nash, TJ Slutz, SA Mehlhorn, TA TI Amplitude reduction of nonuniformities induced by magnetic Rayleigh-Taylor instabilities in Z-pinch dynamic hohlraums SO PHYSICS OF PLASMAS LA English DT Article ID ARRAY Z-PINCHES; SIMULATIONS; TEMPERATURE; IMPLOSION; PLASMA; WIRES AB Z-pinch plasmas are susceptible to the magnetic Rayleigh-Taylor (MRT) instability. The Z-pinch dynamic hohlraum (ZPDH), as implemented on the Z machine at Sandia National Laboratories, is composed of an annular tungsten plasma that implodes onto a coaxial foam convertor. The collision between tungsten Z pinch and convertor launches a strong shock in the foam. Shock heating generates radiation that is trapped by the tungsten Z pinch. The radiation can be used to implode a fuel-filled, inertial confinement fusion capsule. Hence, it is important to understand the influence that the MRT instability has on shock generation. This paper presents results of an investigation to determine the affect that the MRT instability has on characteristics of the radiating shock in a ZPDH. Experiments on Z were conducted in which a 1.5 cm tall, nested array (two arrays with initial diameters of 2.0 and 4.0 cm), tungsten wire plasma implodes onto a 5 mg/cc, CH2 foam convertor to create a similar to135 eV dynamic hohlraum. X-ray pinhole cameras viewing along the ZPDH axis recorded time and space resolved images of emission produced by the radiating shock. These measurements showed that the shock remained circular to within +/- 30-60 mum as it propagated towards the axis, and that it was highly uniform along its height. The measured emission intensities are compared with synthetic x-ray images obtained by postprocessing two-dimensional, radiation magnetohydrodynamic simulations in which the amplitude of MRT perturbations is varied. These simulations accurately reproduce the measured shock trajectory and spatial profiles of the dynamic hohlraum interior emission as a function of time, even for large MRT amplitudes. Furthermore, the radiating shock remains relatively uniform in the axial direction regardless of the MRT amplitude because nonuniformities are tamped by the interaction of the tungsten Z-pinch plasma with the foam. These results suggest that inertial confinement fusion implosions driven by a ZPDH should be relatively free from random radiation symmetry variations produced by Z-pinch instabilities. (C) 2005 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lemke, RW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 23 TC 18 Z9 18 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 2005 VL 12 IS 1 AR 012703 DI 10.1063/1.1819936 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 895LN UT WOS:000226864500043 ER PT J AU Nebel, RA Stange, S Park, J Taccetti, JM Murali, SK Garcia, CE AF Nebel, RA Stange, S Park, J Taccetti, JM Murali, SK Garcia, CE TI Theoretical and experimental studies of kinetic equilibrium and stability of the virtual cathode in an electron injected inertial electrostatic confinement device SO PHYSICS OF PLASMAS LA English DT Article ID OSCILLATING PLASMA SPHERE; POTENTIAL WELL; UNIFORM-DENSITY; FUSION SYSTEMS; PENNING TRAP; FLUID; FOCUS AB This paper explores the electron-electron two-stream stability limit of a virtual cathode in spherical geometry. Previous work using a constant density slab model [R. A. Nebel and J. M. Finn, Phys. Plasmas 8, 1505 (2001)] suggested that the electron-electron two-stream would become unstable when the well depth of the virtual cathode was 14% of the applied voltage. However, experimental tests on INS-e have achieved virtual cathode fractional well depths similar to60% with no sign of instability. Here, studies with a spherical gridless particle code indicate that fractional well depths greater than 90% can be achieved without two-stream instabilities. Two factors have a major impact on the plasma stability: whether the particles are reflected and the presence of angular momentum. If the particles are reflected then they are guaranteed to be in resonance with the electron plasma frequency at some radius. This can lead to the two stream instabilities if the angular momentum is small. If the angular momentum is large enough it stabilizes the instability much the same way as finite temperature stabilizes the two-stream instability in a slab. (C) 2005 American Institute of Physics. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Nebel, RA (reprint author), Los Alamos Natl Lab, Div Theoret, MS K717, Los Alamos, NM 87545 USA. NR 28 TC 16 Z9 17 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 2005 VL 12 IS 1 AR 012701 DI 10.1063/1.1829296 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 895LN UT WOS:000226864500041 ER PT J AU Rose, HA AF Rose, HA TI Langmuir wave self-focusing versus decay instability SO PHYSICS OF PLASMAS LA English DT Article ID STIMULATED BRILLOUIN-SCATTERING; LASER HOT-SPOTS; PLASMA-OSCILLATIONS; FREQUENCY-SHIFT; RAMAN; COLLAPSE AB Electron trapping in a finite amplitude Langmuir wave (LW) leads to a frequency shift, Deltaomega(TP) < 0, and reduced Landau damping. These may lead to modulational instability. Its growth rate and damping threshold, due to escape of trapped electrons at rate v, are calculated in the short wavelength regime. If the background plasma is in thermal equilibrium, it is shown that this trapped particle modulational instability (TPMI) is not possible when klambda(D) > 0.46, while for 0.33 < klambda(D) < 0.46 TPMI requires that the fluctuation wave vector has a component perpendicular to k. the LW wave vector, with lambda(D) being the electron Debye length. Its nonlinear evolution leads to self-focusing. Comparison is made with a reevaluated LW ion acoustic decay instability (LDI): compared to classical estimates, the new linear LDI threshold is lowered by primary LW Deltaomega(TP) since frequency matching leads to wave number and hence damping reduction of the daughter LW. For parameter estimates relevant to a recent stimulated Raman scatter experiment [Kline et al., Phys. Rev. Lett. (submitted)], the LDI and TPMI thresholds cross in the range 0.29 < klambda(D) < 0.33, consistent with the observed LDI regime change. However, if v exceeds a critical value, estimated to be order 1% of the electron plasma frequency, then TPMI is not possible at any wave number. (C) 2005 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Rose, HA (reprint author), Los Alamos Natl Lab, MS-B213, Los Alamos, NM 87545 USA. EM har@lanl.gov NR 37 TC 38 Z9 38 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 2005 VL 12 IS 1 AR 012318 DI 10.1063/1.1829066 PG 14 WC Physics, Fluids & Plasmas SC Physics GA 895LN UT WOS:000226864500027 ER PT J AU Simakov, AN Catto, PJ AF Simakov, AN Catto, PJ TI Drift kinetic equation exact through second order in gyroradius expansion SO PHYSICS OF PLASMAS LA English DT Article ID PLASMA; TRANSPORT; TURBULENCE AB The drift kinetic equation of Hazeltine [R. D. Hazeltine, Plasma Phys. 15, 77 (1973)] for a magnetized plasma of arbitrary collisionality is widely believed to be exact through the second order in the gyroradius expansion. It is demonstrated that this equation is only exact through the first order. The reason is that when evaluating the second-order gyrophase dependent distribution function, Hazeltine neglected contributions from the first-order gyrophase dependent distribution function, and then used this incomplete expression to derive the equation for the gyrophase independent distribution function. Consequently, the second-order distribution function and the stress tensor derived by this approach are incomplete. By relaxing slightly Hazeltine's orderings one is able to obtain a drift kinetic equation accurate through the second order in the gyroradius expansion. In addition, the gyroviscous stress tensor for plasmas of arbitrary collisionality is obtained. (C) 2005 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. RP Simakov, AN (reprint author), Los Alamos Natl Lab, MS K717, Los Alamos, NM 87545 USA. NR 19 TC 25 Z9 25 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JAN PY 2005 VL 12 IS 1 AR 012105 DI 10.1063/1.1823414 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 895LN UT WOS:000226864500007 ER PT S AU Liliental-Weber, Z Zakharov, DN Jasinski, J Yu, KM Wu, J Ager, JW Walukiewicz, W Haller, EE Lu, H Li, SX Schaff, WJ AF Liliental-Weber, Z Zakharov, DN Jasinski, J Yu, KM Wu, J Ager, JW Walukiewicz, W Haller, EE Lu, H Li, SX Schaff, WJ BE Menendez, J VanDeWalle, CG TI Relation between structural and optical properties of InN and In-x,Ga1-xN thin films SO Physics of Semiconductors, Pts A and B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys ID INDIUM NITRIDE; BAND-GAP AB Transmission Electron Microscopy (TEM) and optical measurements obtained from InN and In1-xGaxN films (0 < x < 0.54) grown by Molecular Beam Epitaxy are presented. Energy gaps measured by absorption, PR, and PL for InN films grown on c-plane Al2O3 were in the range of 0.7 eV. No In or other inclusions were observed in these films, ruling out the possibility of a strong Mie scattering mechanism. In the In1-xGaxN films the relationship between the structural properties and the optical properties, in particular the presence or absence of a Stokes shift between absorption and PL, is discussed. TEM studies show that high quality layers do not have a Stokes shift. Some films had compositional ordering; these films also showed a shift between absorption edge and luminescence peak. C1 Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Liliental-Weber, Z (reprint author), Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Zakharov, Dmitri/F-4493-2014; Wu, Junqiao/G-7840-2011; OI Wu, Junqiao/0000-0002-1498-0148; Ager, Joel/0000-0001-9334-9751; Yu, Kin Man/0000-0003-1350-9642 NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 209 EP 210 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900081 ER PT S AU Dalpian, GM Wei, SH AF Dalpian, GM Wei, SH BE Menendez, J VanDeWalle, CG TI Stabilization of zinc-blende semiconductors through 3d impurities and holes SO Physics of Semiconductors, Pts A and B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys AB We propose a method to stabilize the cubic phase of semidconductors that have the hexagonal phase as the most stable one. Our approach consists of doping the host with 3d acceptors. The stabilization occurs because stronger p-d repulsion in the cubic phase shifts its valence band maximum higher that that in the hexagonal phase. As a result, the holes in the cubic phase have lower energy than in the hexagonal phase, thus stabilizing the cubic phase. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Dalpian, GM (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 225 EP 226 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900089 ER PT S AU Carrier, P Wei, SH AF Carrier, P Wei, SH BE Menendez, J VanDeWalle, CG TI Band structure parameters of the nitrides: The origin of the small band gap of InN SO PHYSICS OF SEMICONDUCTORS, PTS A AND B SE AIP Conference Proceedings LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys ID OPTICAL-PROPERTIES; HEXAGONAL INN; ALLOYS; ABSORPTION AB Using the full-potential linear augmented plane waves (FLAPW) method and adding Christensen's gaussian potential to the standard Kohn-Sham equations that allows to correct the band gap in the local density approximation (LDA), we study the chemical trends of the band gap variation in III-V semiconductors and predict that the band gap for InN is 0.8 (+/- 0.1 eV), which is much smaller than previous experimental value of 1.9 eV. The unusually small band gap of InN, that is even smaller than the band gap of InP, is explained in terms of the high electronegativity of nitrogen and consequently the small band gap deformation potential of InN. To understand the possible origin of the measured large band gap, we have calculated the absorption coefficients and effective masses of wurtzite InN and compared the results to the one of GaN. We show that, due to the non-parabolicity of the bands, using the standard linear interpolation scheme as in the experiments, the derived apparent band gap depends on the choice of the scale used in the measurements. The difference between the apparent band gap and the true band gap could be as large as 0.4 eV for InN, overestimating the true band gap. From the calculated effective masses we have calculated the Moss-Burstein shift of the band gap as a function of the carrier density. We find that due to the Moss-Burstein shift, the apparent band gap of InN can reach to 2.0 eV if the electron density in the conduction band is in the order of 10(20). Our observations are consistent with recent experiments, where a low band gap of 0.8 eV in InN is reported. This establishes the low value for the band gap in InN. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 26 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 287 EP 288 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900117 ER PT S AU Yu, KM Walukiewicz, W Wojtowicz, T Denlinger, J Liu, X Furdyna, K AF Yu, KM Walukiewicz, W Wojtowicz, T Denlinger, J Liu, X Furdyna, K BE Menendez, J VanDeWalle, CG TI Effects of Mn site location on the magnetic properties of III1-xMnxV semiconductors SO PHYSICS OF SEMICONDUCTORS, PTS A AND B SE AIP Conference Proceedings LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys ID CURIE-TEMPERATURE; FERROMAGNETISM; GA1-XMNXAS AB We have demonstrated that in ferromagnetic III1-xMnxV semiconductor alloys grown by low temperature molecular beam epitaxy technique, a substantial fraction of the Mn atoms reside in interstitial positions (Mn-I). The Mn, lower the Curie temperature by electrically compensating Mn-Ga acceptors and reducing magnetically active spins. Through a series of experiments that involve varying the film thickness, low temperature annealing, co-doping with Be, as well as modulation doped Al1-yGayAs/Ga1-xMnxAs/Al1-yGayAs heterostructures, we established that the fraction of Mn intersititials present in the thin film is governed by the Fermi level during the growth process itself. This Fermi-level-induced Mn interstitial formation effect imposes an upper limit to the T-C of III1-xMnxV alloys. C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Elect Mat Program, Berkeley, CA 94720 USA. RP Lawrence Berkeley Natl Lab, Div Mat Sci, Elect Mat Program, Berkeley, CA 94720 USA. RI Yu, Kin Man/J-1399-2012 OI Yu, Kin Man/0000-0003-1350-9642 NR 15 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 303 EP 306 PG 4 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900125 ER PT S AU Gao, XPA Boebinger, GS Mills, AP Ramirez, AP Pfeiffer, LN West, KW AF Gao, XPA Boebinger, GS Mills, AP Ramirez, AP Pfeiffer, LN West, KW BE Menendez, J VanDeWalle, CG TI Giant hole-phonon coupling in a strongly interacting two-dimensional (2D) hole system SO Physics of Semiconductors, Pts A and B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys ID HOT-ELECTRONS; REGIME; GAS AB We have studied the temperature dependent phonon emission rate P(7) of a strongly interacting (r(s)>= 22) dilute 2D metallic GaAs hole system through carrier heating experiment. We observe that P(7) changes from P(T) similar to T-5 to P(7) similar to T-7 above 100mK, indicating a crossover from screened piezoelectric(PZ) coupling to screened deformation potential(DP) coupling for hole-phonon scattering. Quantitative comparison with theory shows that the short range DP coupling between the low density holes and phonons is more than ten times stronger than expected in the poorly understood 2D metallic state (E. Abrahams, S.V. Kravchenko, and M.P. Sarachik, Rev. Mod. Phys. 73, 251(2001)). The long range PZ coupling between holes and phonons, however, has an expected magnitude. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Gao, XPA (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 9 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 449 EP 450 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900191 ER PT S AU Lilly, MP Bielejec, E Seamons, JA Reno, JL AF Lilly, MP Bielejec, E Seamons, JA Reno, JL BE Menendez, J VanDeWalle, CG TI Weak localization of dilute 2D electrons in undoped GaAs heterostructures SO Physics of Semiconductors, Pts A and B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys AB The temperature dependence of the resistivity and magnetoresistance of dilute 2D electrons are reported. The temperature dependence of the resistivity can be qualitatively described through phonon and ionized impurity scattering. While the temperature dependence indicates no ln(T) increase in the resistance, a sharp negative magnetoresistance feature is observed at small magnetic fields. This is shown to arise from weak localization. At very low density, we believe weak localization is still present, but cannot separate it from other effects that cause magnetoresistance in the semi-classical regime. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lilly, MP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 453 EP 454 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900193 ER PT S AU Zhao, YF Kim, YH Du, MH Zhang, SB AF Zhao, YF Kim, YH Du, MH Zhang, SB BE Menendez, J VanDeWalle, CG TI Icosahedral quantum dots and 2D quasicrystals for group IV semiconductors SO PHYSICS OF SEMICONDUCTORS, PTS A AND B SE AIP Conference Proceedings LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys AB Group IV semiconductors could have a completely new symmetry when the size is reduced to the range of several nanometers. For Si, the icosahedra are more stable than bulk-like quantum dots QDs) for d < 5 nm (or N < 2400). At a given size, the icosahedral QDs are expected to be the most atom-like QDs of all shapes. A 2D quasicrystal based on the silicon nanowires of five-fold symmetry is also proposed. C1 Natl Renewable Lab, Golden, CO 80401 USA. RP Natl Renewable Lab, Golden, CO 80401 USA. RI Du, Mao-Hua/B-2108-2010; Zhang, Shengbai/D-4885-2013 OI Du, Mao-Hua/0000-0001-8796-167X; Zhang, Shengbai/0000-0003-0833-5860 NR 6 TC 0 Z9 0 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 625 EP 626 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900276 ER PT S AU Seamons, JA Bielejec, E Lilly, MP Reno, JL Du, RR AF Seamons, JA Bielejec, E Lilly, MP Reno, JL Du, RR BE Menendez, J VanDeWalle, CG TI Ballistic to diffuse crossover in long quantum wires SO Physics of Semiconductors, Pts A and B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys AB We report a study on the; uniformity of long quantum wires in the crossover from ballistic to diffuse transport with lengths ranging from 1 gm to 20 mu m. For the 1 mu m wire we measure 15 plateaus quantized at integer values of 2e(2)/h. With increasing length we observe plateaus at conductance values suppressed below the quantized values. With nonlinear fitting to the magnetoresistances we obtain an effective width for the quantum wires. As we find no systematic variation of the effective width as a function of sublevel index for the various length wires, we conclude that we have uniform long single quantum wires up to 20 mu m. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Seamons, JA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 917 EP 918 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900420 ER PT S AU Bielejec, E Seamons, JA Lilly, MP Reno, JL AF Bielejec, E Seamons, JA Lilly, MP Reno, JL BE Menendez, J VanDeWalle, CG TI 1D-1D tunneling between vertically coupled GaAs/AlGaAs quantum wires SO Physics of Semiconductors, Pts A and B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys AB We report low-dimensional transport and tunneling in an independently contacted vertically coupled quantum wire system, with a 7.5 nm barrier between the wires. The derivative of the linear conductance shows evidence for both single wire occupation and coupling between the wires. This provides a map of the subband occupation that illustrates the control that we have over the vertically coupled double quantum wires. Preliminary tunneling results indicate a sharp 1D-1D peak in conjunction with a broad 2D-2D background signal. This 1D-1D peak is sensitively dependent on the top and bottom split gate voltage. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Bielejec, E (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 921 EP 922 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900422 ER PT S AU Kim, YH Heben, MJ Zhang, SB AF Kim, YH Heben, MJ Zhang, SB BE Menendez, J VanDeWalle, CG TI First-principles band offsets of carbon nanotubes with III-V semiconductors SO Physics of Semiconductors, Pts A and B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys AB Band offsets for carbon nanotubes assembled with III-V semiconductors are calculated within first-principles density functional formalism. It turns out that in many cases the calculated mid-gap levels of the semiconducting nanotubes, corresponding to the original graphene Fermi level, are located at 0.5310.08 eV above the valence band maximum of bulk InAs, regardless of the tube diameter and chirality. Direct calculations for the nanotube/GaAs systems confirm the applicability of the above graphene Fermi level theory, as well as the transferability of the band offsets among III-V semiconductors. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kim, YH (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 7 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 1031 EP 1032 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900477 ER PT S AU Zunger, A Dudiy, SV Kim, K Jones, WB AF Zunger, A Dudiy, SV Kim, K Jones, WB BE Menendez, J VanDeWalle, CG TI The inverse band structure approach: Find the atomic configuration that has desired electronic properties SO PHYSICS OF SEMICONDUCTORS, PTS A AND B SE AIP Conference Proceedings LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys AB In conventional band theory, one specifies first the atomic configuration, and then solves for the electronic properties. We consider the inverse process where one specifies fast some target electronic properties, and then searches for atomic configurations that have such properties. Application of the Genetic Algorithm, with additional advantages from its parallel computer implementation, significantly extends our capabilities in treating more demanding IBS problems, as illustrated by searching for the configuration of nitrogen impurity clusters in Gal? that have given properties. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 1121 EP 1122 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900517 ER PT S AU Kim, K Graf, PA Jones, WB AF Kim, K Graf, PA Jones, WB BE Menendez, J VanDeWalle, CG TI Material design via genetic algorithms for semiconductor alloys and superlattices SO Physics of Semiconductors, Pts A and B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 27th International Conference on the Physics of Semiconductors (ICPS-27) CY JUL 26-30, 2004 CL Flagstaff, AZ SP Int Union Pure & Appl Phys, Natl Sci Fdn, AF Off Sci Res, Off Naval Res, Army Res Off, Defense Adv Res Project Agcy, European Off Aerosp Res Dev, Asian Off Aerosp Res & Dev, Lawrence Berkeley Natl Lab, Natl Inst Standards & Technol, Amer Phys Soc, Forum Ind & Appl Phys AB We present an efficient and accurate method for designing materials for electronic applications. Our approach is to search an atomic configuration space by repeatedly applying a forward solver, guiding the search toward the optimal configuration using an evolutionary algorithm. We employ a hierarchical parallelism for the combined forward solver and the genetic algorithm. This enables the optimization process to run on many more processors than would otherwise be possible. We have optimized AlGaAs alloys for maximum bandgap and minimum bandgap for several given compositions. When combined with an efficient forward solver, this approach can be generalized to a wide range of applications in material design. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kim, K (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0257-4 J9 AIP CONF PROC PY 2005 VL 772 BP 1127 EP 1128 PG 2 WC Physics, Condensed Matter SC Physics GA BCQ42 UT WOS:000230723900520 ER PT J AU Melnitchouk, W Ent, R Keppel, CE AF Melnitchouk, W Ent, R Keppel, CE TI Quark-hadron duality in electron scattering SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID DEEP-INELASTIC-SCATTERING; NUCLEON STRUCTURE FUNCTIONS; ELECTROMAGNETIC FORM-FACTORS; NEUTRON SPIN STRUCTURE; QCD SUM-RULES; CHARGED-PION ELECTROPRODUCTION; DYNAMICAL PARTON DISTRIBUTIONS; VIRTUAL COMPTON-SCATTERING; STRUCTURE-FUNCTION G(1)(N); LARGE TRANSVERSE-MOMENTUM AB The duality between partonic and hadronic descriptions of physical phenomena is one of the most remarkable features of strong interaction physics. A classic example of this is in electron-nucleon scattering, in which low-energy cross sections, when averaged over appropriate energy intervals, are found to exhibit the scaling behavior expected from perturbative QCD. We present a comprehensive review of data on structure functions in the resonance region. from which the global and local aspects of duality are quantified. including its flavor. spin and nuclear medium dependence. To interpret the experimental findings, we discuss various theoretical approaches which have been developed to understand the microscopic origins of quark-hadron duality in QCD. Examples from other reactions are used to place duality in a broader context, and future experimental and theoretical challenges are identified. (C) 2004 Elsevier B.V. All rights reserved. C1 Jefferson Lab, Newport News, VA 23606 USA. Hampton Univ, Dept Phys, Hampton, VA 23668 USA. RP Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. EM wmelnitc@jlab.org NR 475 TC 118 Z9 119 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 EI 1873-6270 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD JAN PY 2005 VL 406 IS 3-4 BP 127 EP 301 DI 10.1016/j.physrep.2004.10.004 PG 175 WC Physics, Multidisciplinary SC Physics GA 892BF UT WOS:000226624000001 ER PT J AU Post, DE Votta, LG AF Post, DE Votta, LG TI Computational science demands a new paradigm SO PHYSICS TODAY LA English DT Article ID SIMULATIONS; LESSONS C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Sun Microsyst Inc, Menlo Pk, CA USA. RP Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RI Post, Douglass/L-3773-2014 OI Post, Douglass/0000-0001-9271-0023 NR 20 TC 56 Z9 55 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0031-9228 EI 1945-0699 J9 PHYS TODAY JI Phys. Today PD JAN PY 2005 VL 58 IS 1 BP 35 EP 41 DI 10.1063/1.1881898 PG 7 WC Physics, Multidisciplinary SC Physics GA 884DQ UT WOS:000226065200020 ER PT J AU Abolins, M Schellman, H Rapidis, P Stutte, L Womersley, J AF Abolins, M Schellman, H Rapidis, P Stutte, L Womersley, J TI Harry Louis Melanson SO PHYSICS TODAY LA English DT Biographical-Item C1 Michigan State Univ, E Lansing, MI 48824 USA. Northwestern Univ, Evanston, IL USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Abolins, M (reprint author), Michigan State Univ, E Lansing, MI 48824 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD JAN PY 2005 VL 58 IS 1 BP 67 EP 68 DI 10.1063/1.1881911 PG 2 WC Physics, Multidisciplinary SC Physics GA 884DQ UT WOS:000226065200027 ER PT S AU Cohen, JS AF Cohen, JS BE Yamazaki, Y Wada, M TI Energy and angular distributions of electrons emitted in capture of antiprotons by helium and neon SO Physics with Ultra Slow Antiproton Beams SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Physics with Ultra Slow Antiproton Beams CY MAR 14-16, 2005 CL Wako, JAPAN SP RIKEN, Soc Atom Collis Res DE antiproton; capture; ionization; angular distribution; helium; neon ID FERMION MOLECULAR-DYNAMICS; SEMICLASSICAL DESCRIPTION; ATOMIC-COLLISIONS; SLOW ANTIPROTONS; HYDROGEN-ATOMS; MUONS AB Using results of a previous theoretical treatment of antiproton capture by helium and neon atoms, the energies and angular distributions of the electrons emitted in the capture process are analyzed for various incident antiproton energies. The emitted electron energies are considerably higher for the neon target than for the helium target. The electron energies increase with increasing incident antiproton energies, but this dependence is fairly weak. The angular distributions of the emitted electrons are approximately isotropic. They are similar for helium and neon and depend only weakly on the antiproton energy. The angular distributions of uncaptured antiprotons at similar and somewhat higher collision energies are also presented. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Cohen, JS (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. NR 22 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0282-5 J9 AIP CONF PROC PY 2005 VL 793 BP 98 EP 107 PG 10 WC Physics, Fluids & Plasmas; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Physics GA BDJ57 UT WOS:000233835500007 ER PT J AU Crease, RP AF Crease, RP TI The king is dead. Long live the king! SO PHYSICS WORLD LA English DT Article C1 SUNY Stony Brook, Dept Philosophy, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Crease, RP (reprint author), SUNY Stony Brook, Dept Philosophy, Stony Brook, NY 11794 USA. EM rcrease@notes.cc.sunysb.edu NR 0 TC 0 Z9 0 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD JAN PY 2005 VL 18 IS 1 BP 55 EP 55 PG 1 WC Physics, Multidisciplinary SC Physics GA 895WJ UT WOS:000226894400028 ER PT S AU Cowee, MM Wang, YL Russell, CT Gurnett, DA AF Cowee, MM Wang, YL Russell, CT Gurnett, DA BE Witasse, O Shea, MA TI On the formation of Io's inner torus SO PLANETARY ATMOSPHERES, IONOSPHERES, AND MAGNETOSPHERES SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT 35th COSPAR Scientific Assembly CY JUL 18-25, 2004 CL Paris, FRANCE SP Comm Space Res DE pickup ions; Io; Jupiter; plasma torus ID PLASMA TORUS AB In December 1995 and November 2002, the Galileo spacecraft traversed the inner Io plasma torus on the J0 and A34 passes, respectively. Observations of electron density showed a steep drop off at the inner boundary located between 4.5R(j) and 5R(j) on the two passes, and a much more gradual decrease in the outer torus. The [Wang, Y.-L., Russell, C.T., Raeder, J. The Io mass loading disk: model calculations. Journal of Geophysical Research 106, 26243-26260, 2001] model of torus formation considers multiple ionization and neutralization stages for the pickup ions, and predicts an inner torus boundary location which depends on the local plasma velocity at to. For an inner torus boundary at similar to 4.7Rj,. ions are picked up into a plasma flowing at similar to 37 km/s (74 km/s is the corotation velocity at 5.9R(j)). The steepness of the boundary and the double peaked density structure seen on the two Galileo passes is not reproduced by the [Wang, Y.-L., Russell, C.T., Raeder, J. The Io mass loading disk: model calculations. Journal of Geophysical Research 106, 26243-26260, 2001] model, which considers the source of mass loading at Io to be uniformly distributed around the moon and does not include outward radial convection. Adding this convection to the model, as would be required to maintain a steady state magnetodisk, steepens the inner torus boundary, but does so over very long timescales. The different inner torus density structure observed on the JO and A34 passes is not reproduced by either the [Wang, Y.-L., Russell, C.T., Raeder, J. The lo mass loading disk: model calculations. Journal of Geophysical Research 106, 26243-26260, 2001] or outward radial convection models and indicates the possible occurrence of a large mass loading event in the 7 years between the passes or longitudinal asymmetry in the torus structure. (c) 2005 Published by Elsevier Ltd on behalf of COSPAR. C1 Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. RP Cowee, MM (reprint author), Univ Calif Los Angeles, Inst Geophys & Planetary Phys, 405 Hilgard Ave, Los Angeles, CA 90095 USA. EM mcowee@igpp.ucla.edu OI Russell, Christopher/0000-0003-1639-8298 NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD 0X5 1GB, OXON, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 2005 VL 36 IS 11 SI 2005 BP 2100 EP 2105 DI 10.1016/j.asr.2005.03.048 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BDT68 UT WOS:000235252300009 ER PT J AU Fowler, S Cook, D Thomashow, MF AF Fowler, Sarah Cook, Daniel Thomashow, Michael F. BE Jenks, MA Hasegawa, PM TI The CBF cold-response pathway SO PLANT ABIOTIC STRESS SE Biological Sciences Series LA English DT Article; Book Chapter ID INOSITOL POLYPHOSPHATE 1-PHOSPHATASE; ARABIDOPSIS-THALIANA COR15A; PLANT TRANSCRIPTION FACTORS; MEMBRANE LIPID-COMPOSITION; REGULATED GENE-EXPRESSION; LENGTH CDNA MICROARRAY; LOW-TEMPERATURE; FREEZING TOLERANCE; ABSCISIC-ACID; SIGNAL-TRANSDUCTION C1 [Fowler, Sarah; Cook, Daniel; Thomashow, Michael F.] Michigan State Univ, MSU DOE Plant Res Lab, E Lansing, MI 48824 USA. RP Fowler, S (reprint author), Michigan State Univ, MSU DOE Plant Res Lab, 310 Plant Biol Bldg, E Lansing, MI 48824 USA. NR 120 TC 7 Z9 7 U1 2 U2 4 PU BLACKWELL SCIENCE PUBL PI OXFORD PA OSNEY MEAD, OXFORD OX2 0EL, ENGLAND BN 978-0-470-98850-3 J9 BIOL SCI SER JI Biol. Sci. Ser. PY 2005 BP 71 EP 99 DI 10.1002/9780470988503.ch4 D2 10.1002/9780470988503 PG 29 WC Plant Sciences SC Plant Sciences GA BYB22 UT WOS:000297807400005 ER PT J AU Furno, I Weisen, H Carey, C Angioni, C Behn, R Fable, E Zabolotsky, A AF Furno, I Weisen, H Carey, C Angioni, C Behn, R Fable, E Zabolotsky, A CA TCV team JET-EFDA Contributors TI A new method for the inversion of interferometry data using basis functions derived from singular value decomposition of local measurements in tokamak plasmas SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID L-MODE PLASMAS; PARTICLE PINCH; ASDEX UPGRADE; TCV; JET; TRANSPORT; PROFILE; RECONSTRUCTION; CONSISTENCY; TOMOGRAPHY AB A novel method for inverting time-resolved line-integrated interferometric plasma density measurements is described. The method uses singular value decomposition of local density profiles from Thomson scattering measurements obtained at low sampling rates in the same or equivalent plasmas to determine a set of orthogonal spatial basis functions which is well adapted to the physical processes under investigation. The sought-for density profile is expanded into a limited series of these functions and a solution is calculated by using a simple least-squares fit method. The new method overcomes the difficulties encountered with other methods, such as regularization methods. which smoothen gradients and depend on the availability of accurate measurements in the plasma edge region. The small number of computations required provides for a fast algorithm. This method, which combines the high bandwidth of interferometer systems with the spatial accuracy of Thomson scattering. is applied to invert interferometer measurements in a wide variety of operational regimes in the Tokamak a Configuration Variable and Joint European. Torus (JET) tokamaks. In particular. the collisionality dependence of density peaking observed in ASDEX Upgrade is confirmed in JET H-modes using this method. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Assoc Euratom Confederat Suisse, Ctr Rech Phys Plasmas, EPFL, Lausanne, Switzerland. EURATOM, IPP, Max Planck Inst Plasmaphys, D-85748 Garching, Germany. RP Furno, I (reprint author), Los Alamos Natl Lab, MS E526, Los Alamos, NM 87545 USA. EM furno@lanl.gov NR 41 TC 13 Z9 13 U1 1 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD JAN PY 2005 VL 47 IS 1 BP 49 EP 69 DI 10.1088/0741-3335/47/1/004 PG 21 WC Physics, Fluids & Plasmas SC Physics GA 892CO UT WOS:000226627500004 ER PT S AU Jackson, BP Hopkins, WA Unrine, J Baionno, J Punshon, T AF Jackson, B. P. Hopkins, W. A. Unrine, J. Baionno, J. Punshon, T. BE Holland, G Bandura, DR TI Selenium speciation in amphibian larvae developing in a coal fly ash settling basin SO Plasma Source Mass Spectrometry: Current Trends and Future Developments SE ROYAL SOCIETY OF CHEMISTRY SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 9th International Conference on Plasma Source Mass Spectrometry CY SEP 13-17, 2004 CL Univ Durham, Durham, ENGLAND HO Univ Durham ID PLASMA-MASS SPECTROMETRY; PERFORMANCE LIQUID-CHROMATOGRAPHY; SIZE-EXCLUSION CHROMATOGRAPHY; ICP-MS; FISH; HPLC; QUANTIFICATION; IDENTIFICATION; FRACTIONATION; SEPARATION C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC USA. RP Jackson, BP (reprint author), Univ Georgia, Savannah River Ecol Lab, Aiken, SC USA. NR 32 TC 0 Z9 0 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 0260-6291 BN 0-85404-663-1 J9 ROY SOC CH PY 2005 IS 301 BP 225 EP 234 PG 10 WC Spectroscopy SC Spectroscopy GA BEK76 UT WOS:000237611600019 ER PT J AU Robertson, MP Igel, H Baertsch, R Haussler, D Ares, M Scott, WG AF Robertson, MP Igel, H Baertsch, R Haussler, D Ares, M Scott, WG TI The structure of a rigorously conserved RNA element within the SARS virus genome SO PLOS BIOLOGY LA English DT Article ID ACUTE RESPIRATORY SYNDROME; 30S RIBOSOMAL-SUBUNIT; CRYSTAL-STRUCTURE; G-QUARTET; MACROMOLECULAR MIMICRY; TRANSLATION INITIATION; ANGSTROM RESOLUTION; PROTEIN; BINDING; CORONAVIRUS AB We have solved the three- dimensional crystal structure of the stem- loop II motif ( s2m) RNA element of the SARS virus genome to 2.7- Angstrom resolution. SARS and related coronaviruses and astroviruses all possess a motif at the 39 end of their RNA genomes, called the s2m, whose pathogenic importance is inferred from its rigorous sequence conservation in an otherwise rapidly mutable RNA genome. We find that this extreme conservation is clearly explained by the requirement to form a highly structured RNA whose unique tertiary structure includes a sharp 908 kink of the helix axis and several novel longer- range tertiary interactions. The tertiary base interactions create a tunnel that runs perpendicular to the main helical axis whose interior is negatively charged and binds two magnesium ions. These unusual features likely form interaction surfaces with conserved host cell components or other reactive sites required for virus function. Based on its conservation in viral pathogen genomes and its absence in the human genome, we suggest that these unusual structural features in the s2m RNA element are attractive targets for the design of anti- viral therapeutic agents. Structural genomics has sought to deduce protein function based on three- dimensional homology. Here we have extended this approach to RNA by proposing potential functions for a rigorously conserved set of RNA tertiary structural interactions that occur within the SARS RNA genome itself. Based on tertiary structural comparisons, we propose the s2m RNA binds one or more proteins possessing an oligomer- binding- like fold, and we suggest a possible mechanism for SARS viral RNA hijacking of host protein synthesis, both based upon observed s2m RNA macromolecular mimicry of a relevant ribosomal RNA fold. C1 Univ Calif Santa Cruz, Ctr Mol Biol RNA, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Dept Chem & Biochem, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Dept Mol Cell & Dev Biol, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Howard Hughes Med Inst, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Dept Biomol Engn, Santa Cruz, CA 95064 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Scott, WG (reprint author), Univ Calif Santa Cruz, Ctr Mol Biol RNA, Santa Cruz, CA 95064 USA. EM wgscott@chemistry.ucsc.edu OI Ares, Manny/0000-0002-2552-9168; Baertsch, Robert/0000-0002-4733-2649 NR 46 TC 42 Z9 44 U1 1 U2 1 PU PUBLIC LIBRARY SCIENCE PI SAN FRANCISCO PA 185 BERRY ST, STE 1300, SAN FRANCISCO, CA 94107 USA SN 1544-9173 J9 PLOS BIOL JI PLoS. Biol. PD JAN PY 2005 VL 3 IS 1 BP 86 EP 94 AR e5 DI 10.1371/journal.pbio.0030005 PG 9 WC Biochemistry & Molecular Biology; Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics GA 899UC UT WOS:000227169800012 PM 15630477 ER PT J AU Stephenson, GB Streiffer, SK Fong, DD Murty, MVR Auciello, O Fuoss, PH Eastman, JA Munkholm, A Thompson, C AF Stephenson, G. B. Streiffer, S. K. Fong, D. D. Murty, M. V. Ramana Auciello, O. Fuoss, P. H. Eastman, J. A. Munkholm, A. Thompson, Carol BE Waser, R Bottger, U Tiedke, S TI In-Situ Synchrotron X-ray Studies of Processing and Physics of Ferroelectric Thin Films SO POLAR OXIDES: PROPERTIES, CHARACTERIZATION, AND IMAGING LA English DT Article; Book Chapter ID CHEMICAL-VAPOR-DEPOSITION; PHASE-TRANSITIONS; SURFACE; POLARIZATION; SCATTERING; PBTIO3 AB To understand the influence of epitaxial strain, depolarizing field, and intrinsic surface effects on the ferroelectric transition, we have investigated ferroelectric thin films using synchrotron x-ray scattering. Here we summarize real-time studies of epitaxial PbTiO3 film growth on SrTiO3 by metalorganic chemical vapor deposition (MOCVD), and in situ studies of the ferroelectric transition as a function of temperature and film thickness. The ability to monitor growth in real time using x-ray scattering allows us to produce films with smooth interfaces, well-defined strain states, and thicknesses controlled to sub-unit-cell accuracy. We find that the ferroelectric phase forms as 180 degrees. stripe domains in these films, with a thickness-dependent T-c. The dependence of the stripe period on film thickness is in agreement with theory. For thicker films (e.g. 40 nm), we find that T-c is elevated above the unstressed bulk value by an amount that agrees with theory for the effect of epitaxial strain. However, the observed decrease of T-c for smaller film thickness is significantly larger than that expected solely due to 180 degrees stripe domains, indicating that intrinsic surface or interface effects may also be important. C1 [Eastman, J. A.] Argonne Natl Lab, Argonne, IL 60439 USA. [Munkholm, A.] Lumileds Lighting, San Jose, CA USA. [Thompson, Carol] No Illinois Univ, De Kalb, IL 60115 USA. EM stephenson@anl.gov OI Eastman, Jeff/0000-0002-0847-4265; Thompson, Carol/0000-0003-3832-4855 NR 25 TC 0 Z9 0 U1 0 U2 1 PU BLACKWELL SCIENCE PUBL PI OXFORD PA OSNEY MEAD, OXFORD OX2 0EL, ENGLAND BN 978-3-52760-465-4 PY 2005 BP 151 EP 161 PG 11 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BZH05 UT WOS:000301591600009 ER PT J AU Kleemann, W Samara, GA Dec, J AF Kleemann, Wolfgang Samara, George A. Dec, Jan BE Waser, R Bottger, U Tiedke, S TI Relaxor Ferroelectrics - from Random Field Models to Glassy Relaxation and Domain States SO POLAR OXIDES: PROPERTIES, CHARACTERIZATION, AND IMAGING LA English DT Article; Book Chapter ID DIFFUSE PHASE-TRANSITION; LEAD MAGNESIUM NIOBATE; ISING ANTIFERROMAGNET; ORDER-PARAMETER; SBN-CE; SCATTERING; DYNAMICS; BEHAVIOR; POLARIZATION; PBMG1/3NB2/3O3 AB Substitutional charge disorder giving rise to quenched electric random-fields (RFs) is probably at the origin of the peculiar behavior of relaxor ferroelectrics, which are primarily characterized by their strong frequency dispersion of the dielectric response and by an apparent lack of macroscopic symmetry breaking at the phase transition. Spatial fluctuations of the RFs correlate the dipolar fluctuations and give rise to polar nanoregions in the paraelectric regime. The dimension of the order parameter decides upon whether the ferroelectric phase transition is destroyed (e.g. in cubic PbMg1/3Nb2/3O3, PMN) or modified towards RF Ising model behavior (e.g. in tetragonal Sr1-xBaxNb2O6, SBN, x approximate to 0.4). Frustrated interaction between the polar nanoregions in cubic relaxors gives rise to cluster glass states as evidenced by strong pressure dependence, typical dipolar slowing-down and theoretically treated within a spherical random bond-RF model. On the other hand, freezing into a domain state takes place in uniaxial relaxors. Below T-c approximate to 350K frozen-in nanodomains have been evidenced in SBN by piezoresponse force microscopy (PFM). RF pinning of the domain walls gives rise to non-Debye dielectric response, which is relaxation- and creep-like at radio- and very low frequencies, respectively. At T-c non-classical critical behavior with critical exponents gamma approximate to 1.8, beta approximate to 0.1 and alpha approximate to 0 is encountered in accordance with the RF Ising model. C1 [Kleemann, Wolfgang; Dec, Jan] Univ Duisburg Essen, Angew Phys, D-47048 Duisburg, Germany. [Samara, George A.] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Dec, Jan] Univ Silesia, Dept Phys, PL-40480 Katowice, Poland. RP Kleemann, W (reprint author), Univ Duisburg Essen, Angew Phys, D-47048 Duisburg, Germany. EM kleemann@uni-duisburg.de NR 66 TC 21 Z9 21 U1 0 U2 1 PU BLACKWELL SCIENCE PUBL PI OXFORD PA OSNEY MEAD, OXFORD OX2 0EL, ENGLAND BN 978-3-52760-465-4 PY 2005 BP 275 EP 301 PG 27 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BZH05 UT WOS:000301591600016 ER PT J AU Golas, J Kubica, B Reczynski, W Kwiatek, WM Jakubowska, M Skiba, M Stobinski, M Dutkiewiez, EM Posmyk, G Jones, KW Olko, M Gorecki, J AF Golas, J Kubica, B Reczynski, W Kwiatek, WM Jakubowska, M Skiba, M Stobinski, M Dutkiewiez, EM Posmyk, G Jones, KW Olko, M Gorecki, J TI Preliminary studies of sediments from the Dobczyce drinking water reservoir SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES LA English DT Article DE sediments; Dobczyce reservoir; trace elements; natural and artificial radionuclides ID ADSORPTION; CS-137 AB The analysis of river and lake sediments indicates that the physical, chemical, biochemical and geochemical processes that influence the fate of toxic compounds and elements in sediments are numerous and complex (for example: sorption - desorption, oxidation - reduction, ion-exchange, biological activity). Due to the above-mentioned general statement, only a long term and complex research programme can lead to satisfactory answers to the questions relating to possible changes of water and environmental quality in the future. The aim of our study consisted in physical and chemical characterisation of sediments in in-depth profiles taken from the Dobczyce reservoir in southern Poland that is a main source of drinking water for the city of Krakow. Due to morphological reasons, 7 layers of sediment samples were distinguished from the ground level to about 90 cm below (total thickness of the sediments in the sampling site). Analysis of grain size distribution and application of x-ray diffraction method, enabled mineralogical description of sediments. The use of proton-induced x-ray emission (PIXE) and atomic absorption spectrometry (AAS) revealed elemental composition of the samples (Al, P, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn). Concentrations of natural K-40 and artificial Cs-137 radionuclides were determined by the use of gamma spectrometry. The following facts were established: 1) the oldest (deepest) and newest, recently deposited layers of sediments are similar in their physical and chemical properties. It means that the inflow of contaminants and biogenic compounds to the reservoir has changed little since it was constructed and filled with water; 2) the severe flood in 1997 changed significantly sediment composition and, in fact, led to purification of sediments in the Dobczyce reservoir. C1 AGH Univ Sci & Technol, Krakow, Poland. Polish Acad Sci, Inst Nucl Phys, PL-31342 Krakow, Poland. Jagiellonian Univ, Krakow, Poland. Brookhaven Natl Lab, Upton, NY 11973 USA. Krakow Water & Sewage Co, Krakow, Poland. RP Kubica, B (reprint author), AGH Univ Sci & Technol, Krakow, Poland. EM barbara.kubica@ifj.edu.pl RI Jakubowska, Malgorzata/J-3525-2015 OI Jakubowska, Malgorzata/0000-0002-0192-4083 NR 24 TC 10 Z9 10 U1 2 U2 9 PU HARD PI OLSZTYN 5 PA POST-OFFICE BOX, 10-718 OLSZTYN 5, POLAND SN 1230-1485 J9 POL J ENVIRON STUD JI Pol. J. Environ. Stud. PY 2005 VL 14 IS 5 BP 577 EP 584 PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA 960XB UT WOS:000231625400006 ER PT S AU Song, J Bertozzi, CR AF Song, J Bertozzi, CR BE Cheng, HN Gross, RA TI Functional hydrogel-biomineral composites inspired by natural bone SO POLYMER BIOCATALYSIS AND BIOMATERIALS SE ACS SYMPOSIUM SERIES LA English DT Article; Proceedings Paper CT Symposium on Polymer Biocatalysis and Biomaterials held at the 2003 ACS National Meeting CY SEP, 2003 CL New York, NY SP Amer Chem Soc ID HYDROXYAPATITE; SEQUENCES; COATINGS AB A urea-mediated mineralization technique was developed to enable the formation of pHEMA-based hydrogel-calcium phosphate composites with excellent polymer-mineral interfacial adhesion strength that is desirable for bone mimics. This mineralization method was also applied to generate more sophisticated composites containing functional hydrogels that possess anionic groups mimicking the extracellular matrix proteins in bone. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem & Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. RP Song, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 SIXTEENTH ST NW, WASHINGTON, DC 20036 USA SN 0097-6156 BN 0-8412-3917-7 J9 ACS SYM SER PY 2005 VL 900 BP 96 EP 106 PG 11 WC Chemistry, Multidisciplinary; Materials Science, Biomaterials; Polymer Science SC Chemistry; Materials Science; Polymer Science GA BCK35 UT WOS:000229731100007 ER PT S AU Chakraborty, S Sahoo, B Teraoka I Miller, LM Gross, RA AF Chakraborty, S Sahoo, B Teraoka, I Miller, LM Gross, RA BE Cheng, HN Gross, RA TI Enzyme-catalyzed regioselective modification of starch nanoparticles SO POLYMER BIOCATALYSIS AND BIOMATERIALS SE ACS Symposium Series LA English DT Review CT Symposium on Polymer Biocatalysis and Biomaterials held at the 2003 ACS National Meeting CY SEP, 2003 CL New York, NY SP Amer Chem Soc ID RING-OPENING POLYMERIZATION; ORGANIC-SOLVENTS; RELEASE; DRUGS; AMYLOSE; WATER; CARRIER; SYSTEM AB This chapter describes the selective esterification of starch nanoparticles catalyzed by Candida antartica Lipase B (CAL-B) in its immobilized (Novozyme 435) and free (SP-525) forms. The starch nanoparticles were made accessible for acylation reactions by formation of Aerosol-OT (AOT, bis[2-ethylhexyl]sodium sulfosuccinate) stabilized microemulsions. Analysis of these particles by light scattering showed at the high and low ends of the distribution aggregates with many 40-nm nanoparticles and AOT-stabilized micelles with one or two 40 nm starch nanoparticles, respectively. Acylation of the starch nanoparticles in microemulsions at 40 degrees C for 48 h with vinyl stearate, E-caprolactone and maleic anhydride gave products with degrees of substitution (D.S.) of 0.8, 0.6 and 0.4, respectively. In all cases, substitution occurred regioselectively at the C-6 position of the glucose repeat units. The acylated particles after surfactant removal retained nanodimensions and could be redispersed in DMSO or water. Infrared microspectroscopy (IRMS) showed that AOT coated starch nanoparticles can diffuse into the outer 50 mu m shell of catalyst beads. The close proximity of the lipase and substrates promotes the modification reactions. C1 Polytech Univ, NSF, Ctr Biocatalysis & Bioprocessing Macromol, Othmer Dept chem & Biol Sci & Lab, Brooklyn, NY 11201 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. RP Gross, RA (reprint author), Polytech Univ, NSF, Ctr Biocatalysis & Bioprocessing Macromol, Othmer Dept chem & Biol Sci & Lab, 6 Metrotech Ctr, Brooklyn, NY 11201 USA. NR 31 TC 2 Z9 2 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 SIXTEENTH ST NW, WASHINGTON, DC 20036 USA SN 0097-6156 BN 0-8412-3917-7 J9 ACS SYM SER JI ACS Symp. Ser. PY 2005 VL 900 BP 246 EP 265 PG 20 WC Chemistry, Multidisciplinary; Materials Science, Biomaterials; Polymer Science SC Chemistry; Materials Science; Polymer Science GA BCK35 UT WOS:000229731100017 ER PT J AU Gillen, KT Bernstein, R Derzon, DK AF Gillen, KT Bernstein, R Derzon, DK TI Evidence of non-Arrhenius behaviour from laboratory aging and 24-year field aging of polychloroprene rubber materials SO POLYMER DEGRADATION AND STABILITY LA English DT Article DE aging; lifetime prediction; chloroprene rubber; Arrhenius extrapolation; oxygen consumption ID POLY(BUTYLENE TEREPHTHALATE); THERMAL-OXIDATION; DEGRADATION; LIFETIME; POLYMERS; EXTRAPOLATION; POLYPROPYLENE; POLYETHYLENE; TEMPERATURE; COPOLYMER AB High-temperature oven aging exposures from 110 C to 80 C have been conducted on a commercial chloroprene rublter rabie jacketing material where the time-dependent degradation at each temperature is monitored by following the ultimate tensile elongation. By time-temperature superposing the results at the lowest experimental temperature (80degreesC). empirical shift factors are first derived and then analysed using the conventional Arrhenius approach and finally extrapolated using the derived activation energy E-a of 96kJ/mol in order to make predictions at 25degreesC. To test the constant E-a assumption underlying the Arrhenius extrapolation, we conducted oxygen consumption measurements at six temperatures ranging from 25degreesC to 95degreesC and found evidence for a slow drop in E-a from similar to96 kJ/cool above 80degreesC to an average value of similar to82 kJ/mol below 80degreesC. This curvature predicts a 50% reduction in room temperature lifetime and suggests that certain higher E-a degradation proca.ses become lag important as room temperature is approached. Analyses of the production rates for CO2 show that CO2 becomes less important relative to the oxygen consumed as the temperature is lowered, evidence in accord with the above suggestion. Further evident: for a similar drop in E, (from 89 kJ/mol above 70 C to 71 kJ/mol below 70 C) comes from comparisons of accelerated aging elongation data taken similar to25 years ago on another chloroprene rubber cable jacketing material with recent elongation results taken on samples that have aged for similar to24 years at similar to24degreesC. Published by Elsevier Ltd. C1 Sandia Natl Labs, Organ Mat Dept, Albuquerque, NM 87185 USA. RP Gillen, KT (reprint author), Sandia Natl Labs, Organ Mat Dept, POB 5800, Albuquerque, NM 87185 USA. EM ktgille@sandia.gov NR 27 TC 53 Z9 56 U1 3 U2 28 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0141-3910 J9 POLYM DEGRAD STABIL JI Polym. Degrad. Stabil. PD JAN PY 2005 VL 87 IS 1 BP 57 EP 67 DI 10.1016/j.polymdegradstab.2004.06.010 PG 11 WC Polymer Science SC Polymer Science GA 879UC UT WOS:000225743400008 ER PT S AU Hsu, CH Feng, WC AF Hsu, CH Feng, WC BE Falsafi, B Vijaykumar, TN TI Effective dynamic voltage scaling through CPU-boundedness detection SO POWER-AWARE COMPUTER SYSTEMS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 4th International Workshop on Power-Aware Computer Systems CY DEC 05, 2004 CL Portland, OR AB Dynamic voltage scaling (DVS) allows a program to execute at a non-peak CPU frequency in order to reduce CPU power, and hence, energy consumption; however, it is oftentimes done at the expense of performance degradation. For a program whose execution time is bounded by peripherals' performance rather than the CPU speed, applying DVS to the program will result in negligible performance penalty. Unfortunately, existing DVS-based power-management algorithms are conservative in the sense that they overly exaggerate the impact that the CPU speed has on the execution time. We propose a new DVS algorithm that detects the CPU-boundedness of a program on the fly (via a regression method on the past MIPS rate) and then adjusts the CPU frequency accordingly. To illustrate its effectiveness, we compare our algorithm with other DVS algorithms on real systems via physical measurements. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hsu, CH (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM chunghsu@lanl.gov; feng@lanl.gov NR 21 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29790-1 J9 LECT NOTES COMPUT SC PY 2005 VL 3471 BP 135 EP 149 PG 15 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BDQ33 UT WOS:000234885200010 ER PT J AU Hale, LC Wulff, TA Sedgewick, JC AF Hale, LC Wulff, TA Sedgewick, JC TI Testing a low-influence spindle drive motor SO PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY LA English DT Article DE slotless; brushless dc motor; precision spindle; air bearing; hydrostatic; diamond turning; error motion AB Precision spindles used for diamond turning and other applications requiring low error motion generally require a drive system that ideally applies a pure torque to the rotating spindle. Frequently a frameless motor, that is, one without its own bearings, is directly coupled to the spindle to make a compact and simple system having high resonant frequencies. Although in addition to delivering drive torque, asymmetries in the motor cause it to generate disturbance loads (forces and moments) which influence the spindle error motion of the directly coupled system. This paper describes the tests and results for a particular frameless, brushless dc motor that was originally developed for military and space applications requiring very low torque ripple. Because the construction of the motor should also lead to very low disturbance loads, it was selected for use on a new diamond turning and grinding machine under developed at Lawrence Livermore National Laboratory. The level of influence for this motor-spindle combination is expected to be of order one nanometer for radial and axial error motion. (C) 2004 Elsevier Inc. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Air Corp, Dover, NH 03820 USA. RP Hale, LC (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM hale6@llnl.gov NR 3 TC 2 Z9 2 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0141-6359 J9 PRECIS ENG JI Precis. Eng.-J. Int. Soc. Precis. Eng. Nanotechnol. PD JAN PY 2005 VL 29 IS 1 BP 1 EP 10 DI 10.1016/j.precisioneng.2004.03.002 PG 10 WC Engineering, Multidisciplinary; Engineering, Manufacturing; Nanoscience & Nanotechnology; Instruments & Instrumentation SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation GA 878WR UT WOS:000225678600001 ER PT S AU Zhang, Y Gao, F Jiang, W McCready, DE Weber, WJ AF Zhang, Y Gao, F Jiang, W McCready, DE Weber, WJ BE Zhong, ZY Saka, H Kim, TH Holm, EA Han, YF Xie, XS TI Studies of damage accumulation in 4H silicon carbide by ion-channeling techniques SO PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 5th Pacific Rim International Conference on Advanced Materials and Processing CY NOV 02-05, 2004 CL Beijing, PEOPLES R CHINA SP Chinese Soc Met, Japan Inst Met, Korea Inst Met & Mat, Minerals, Met & Mat Soc DE silicon carbide; defects; ion irradiation; molecular dynamics; ion channeling ID AMORPHIZATION; DEFECTS; TEMPERATURE; IRRADIATION; ENERGETICS; RECOVERY AB Single crystal 4H-SiC was irradiated with 2 MeV Au ions at 165 K. Ion-induced defect configurations and damage accumulation were studied by ion-channeling techniques along the < 0001 >, < 4403 > and < 2201 > directions. A nonlinear dependence of damage accumulation is observed for both the Si and C sublattices along all three directions, and the relative disorder observed along the < 4403 > and < 2201 > directions is much higher than that along the < 0001 > direction. The damage accumulation can be described by a disorder accumulation model, which indicates that defect-stimulated amorphization is the primary amorphization mechanism in SiC, and the high disorder level for the large off-axis angles is attributed to particular defect configurations. Molecular dynamics (MD) simulations demonstrate that most single interstitial configurations are shielded by Si and C atoms on the lattice sites along the < 0001 > direction, which significantly reduces their contribution to the backscattering/reaction yield along the < 0001 > direction. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Zhang, Y (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM yanwen.zhang@pnl.gov; fei.gao@pnl.gov; weilin.jiang@pnl.gov; david.mccready@pnl.gov; bill.weber@pnl.gov RI Weber, William/A-4177-2008; Gao, Fei/H-3045-2012; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 14 TC 1 Z9 1 U1 0 U2 5 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-960-1 J9 MATER SCI FORUM PY 2005 VL 475-479 BP 1341 EP 1344 PN 1-5 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BBR99 UT WOS:000227494701114 ER PT S AU Weber, WJ Gao, F Devanathan, R Jiang, W Zhang, Y AF Weber, WJ Gao, F Devanathan, R Jiang, W Zhang, Y BE Zhong, ZY Saka, H Kim, TH Holm, EA Han, YF Xie, XS TI Defects and ion-solid interactions in silicon carbide SO PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 5th Pacific Rim International Conference on Advanced Materials and Processing CY NOV 02-05, 2004 CL Beijing, PEOPLES R CHINA SP Chinese Soc Met, Japan Inst Met, Korea Inst Met & Mat, Minerals, Met & Mat Soc DE silicon carbide; defects; ion implantation; amorphization ID COMPUTER-SIMULATION; INTERATOMIC POTENTIALS; MOLECULAR-DYNAMICS; DAMAGE EVOLUTION; RECOVERY; DEVICES; SI; AMORPHIZATION; EFFICIENCY; CASCADE AB Atomic-level simulations are used to determine defect production, cascade-overlap effects, and defect migration energies in SiC. Energetic C and Si collision cascades primarily produce single interstitials, mono-vacancies, antisite defects, and small defect clusters, while amorphous clusters are produced within 25% of Au cascades. Cascade overlap results in defect stimulated cluster growth that drives the amorphization process. The good agreement of disordering behavior and changes in volume and elastic modulus obtained computationally and experimentally provides atomic-level interpretation of experimentally observed features. Simulations indicate that close-pair recombination activation energies range from 0.24 to 0.38 eV, and long-range migration energies for interstitials and vacancies are determined. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM bill.weber@pnl.gov; fei.gao@pnl.gov; ram.devanathan@pnl.gov; weilin.jiang@pnl.gov; yanwen.zhang@pnl.gov RI Weber, William/A-4177-2008; Gao, Fei/H-3045-2012; Devanathan, Ram/C-7247-2008; OI Weber, William/0000-0002-9017-7365; Devanathan, Ram/0000-0001-8125-4237; Jiang, Weilin/0000-0001-8302-8313 NR 35 TC 0 Z9 0 U1 0 U2 6 PU TRANS TECH PUBLICATIONS LTD PI DURNTEN-ZURICH PA KREUZSTRASSE 10, 8635 DURNTEN-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-960-1 J9 MATER SCI FORUM PY 2005 VL 475-479 BP 1345 EP 1350 PN 1-5 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BBR99 UT WOS:000227494701115 ER PT S AU Tang, W Dennis, KW Kramer, MJ Anderson, IE McCallum, RW AF Tang, W Dennis, KW Kramer, MJ Anderson, IE McCallum, RW BE Zhong, ZY Saka, H Kim, TH Holm, EA Han, YF Xie, XS TI New YDy-based R-2(Fe,Co)(14)B melt-spun magnets (R=Y+Dy+Nd) SO PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 5th Pacific Rim International Conference on Advanced Materials and Processing CY NOV 02-05, 2004 CL Beijing, PEOPLES R CHINA SP Chinese Soc Met, Japan Inst Met, Korea Inst Met & Mat, Minerals, Met & Mat Soc DE rare earth materials and compounds; R2Fe14B phase; magnetocrystalline anisotropy; permanent magnets; melting spinning ID MAGNETIZATION; ANISOTROPY AB The effects of the ratio of Y to Dy as well as the effect of Nd and Co substitutions on magnetic properties in [Nd-x(YDy)(0.5(1-x))](2.2)Fe14-yCoyB ribbons melt-spun at 22 m/s have been systematically studied. (Y1-zDyz)(2.2)Fe14B ribbons with a ratio z of 0.25 or 0.5 simultaneously obtains a smaller temperature coefficient of remanence (alpha) and coervicity (beta) which are much smaller than those of Nd-based Nd2Fe14B ribbons. In [Nd-x(YDy)(0.5(1-x))](2.2)Fe14-yCOyB ribbons, Nd substitution (x = 0 to 0.8) can improve the maximum energy product (BH)(max) of annealed ribbons but degrades the temperature stability of the magnetic properties. The ribbons with x = 0.4 and y = 0 yield a (BH)(max) of 8.7 MGOe. For these ribbons, the alpha and beta are -0.07 and -0.31%/degrees C in the temperature range of 27 to 127 degrees C, respectively. Increasing Co (x) from 0 to 3, slightly decreases coercivity H-cj from 21.5 to 16.3 kOe, but keeps the (BH)(max) in the range of 8.6 to 10.2 MGOe. The optimal sample with x = 0.5 and y = 1.5 obtains a (BH) a of 10.2 and 5.0 MGOe at 27 and 250 degrees C, respectively. Its a and beta are -0.11 and -0.30%/degrees C, respectively. These results show that studied ribbons are very promising to develop into high temperature isotropic bonded magnets capable of operating at or above 180 degrees C. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. EM weitang@ameslab.gov NR 8 TC 9 Z9 9 U1 0 U2 1 PU TRANS TECH PUBLICATIONS LTD PI DURNTEN-ZURICH PA KREUZSTRASSE 10, 8635 DURNTEN-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-960-1 J9 MATER SCI FORUM PY 2005 VL 475-479 BP 2155 EP 2160 PN 1-5 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BBR99 UT WOS:000227494702117 ER PT S AU Liu, S Trivedi, R AF Liu, S Trivedi, R BE Zhong, ZY Saka, H Kim, TH Holm, EA Han, YF Xie, XS TI Microstructure evolution in a directional solidification process SO PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 5th Pacific Rim International Conference on Advanced Materials and Processing CY NOV 02-05, 2004 CL Beijing, PEOPLES R CHINA SP Chinese Soc Met, Japan Inst Met, Korea Inst Met & Mat, Minerals, Met & Mat Soc DE directional solidification; microstructure evolution; convection; diffusive growth ID DENDRITIC GROWTH; THIN SAMPLES; STABILITY; ALLOY AB Models and theories of the microstructure evolution in a directional solidification (DS) process will be firstly addressed. Discrepancies between theories and experiments will be presented. For the thin film sample growth in a temperature gradient stage, the geometrical constraint makes it difficult to compare the experimental primary spacing with theoretical predictions. While for a bulk sample growth, fluid flow always exists in the solidification process despite that the growth interface rejects a lighter or heavier solute. Based on these analyses, the appropriate techniques to conduct DS experiments are proposed that can be used to test models. One is the solidification in a capillary sample where a single cell/dendrite grows. While for array growth in 3 dimensions, long-duration microgravity experiments will be the only viable way to obtain meaningful results. C1 Iowa State Univ, Program Met & Engn Phys, Ames Lab, USDOE, Ames, IA 50011 USA. RP Liu, S (reprint author), Iowa State Univ, Program Met & Engn Phys, Ames Lab, USDOE, Ames, IA 50011 USA. EM shanliu@ameslab.gov; trivedi@amesiab.gov NR 16 TC 0 Z9 0 U1 1 U2 1 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-960-1 J9 MATER SCI FORUM PY 2005 VL 475-479 BP 2757 EP 2760 PN 1-5 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BBR99 UT WOS:000227494703055 ER PT S AU Lee, SM Moon, BM Fleury, E Ahn, HS Kim, DH Kim, WT Sordelet, DJ AF Lee, SM Moon, BM Fleury, E Ahn, HS Kim, DH Kim, WT Sordelet, DJ BE Zhong, ZY Saka, H Kim, TH Holm, EA Han, YF Xie, XS TI Effect of thermal spray processing techniques on the microstructure and properties of Ni-based amorphous coatings SO PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 5th Pacific Rim International Conference on Advanced Materials and Processing CY NOV 02-05, 2004 CL Beijing, PEOPLES R CHINA SP Chinese Soc Met, Japan Inst Met, Korea Inst Met & Mat, Minerals, Met & Mat Soc DE Ni amorphous coating; gas atomization; laser cladding; vacuum plasma spraying; glass forming ability; wear test; tribological properties ID ALLOYS AB Metallic amorphous materials have been widely developed thanks to the outstanding proper-ties including high chemical stability, mechanical strength, and magnetic properties. However, with the exception of a few compositions, the limiting factor is the critical cooling rate for the formation of the amorphous phase. For many applications, it is only the contact surface properties that are important, thus the use of coating techniques such as thermal sprayings has several attractive features. In this paper, we present the microstructure of Ni-based amorphous coatings prepared by laser cladding and vacuum plasma spraying. The utilization of plasma spraying to deposit atomized powder enabled the formation of fully amorphous coating, laser cladding resulted in mostly crystallized structures. Glass forming ability and wear properties of the coatings were discussed as a function of the coating microstructure. C1 Korea Inst Ind Technol, Inchon, South Korea. Korea Inst Sci & Technol, Seoul 130650, South Korea. Yonsei Univ, Ctr Noncrystalline Mat, Seoul 120749, South Korea. Chongju Univ, Div Appl Sci, Chongju, South Korea. Iowa State Univ, Ames Lab, Dept Mat Sci & Engn, Ames, IA USA. RP Korea Inst Ind Technol, Inchon, South Korea. EM smlee@kitech.re.kr; moonbm@kitech.re.kr; fIeury@kist.re.kr; hsahn@kist.re.kr; dohkim@yonsei.ac.kr; wontae@chongju.ac.kr; sordelet@iowa.arnes.ac NR 3 TC 0 Z9 0 U1 0 U2 4 PU TRANS TECH PUBLICATIONS LTD PI DURNTEN-ZURICH PA KREUZSTRASSE 10, 8635 DURNTEN-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-960-1 J9 MATER SCI FORUM PY 2005 VL 475-479 BP 2887 EP 2890 PN 1-5 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BBR99 UT WOS:000227494703084 ER PT S AU Gao, F Bylaska, EJ Weber, WJ AF Gao, F Bylaska, EJ Weber, WJ BE Zhong, ZY Saka, H Kim, TH Holm, EA Han, YF Xie, XS TI Defect properties in GaN: Ab initio and empirical potential calculations SO PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 5th Pacific Rim International Conference on Advanced Materials and Processing CY NOV 02-05, 2004 CL Beijing, PEOPLES R CHINA SP Chinese Soc Met, Japan Inst Met, Korea Inst Met & Mat, Minerals, Met & Mat Soc DE gallium nitride; defects; ab initio calculations; molecular dynamics simulations ID GALLIUM NITRIDE; NATIVE DEFECTS AB The defect properties and atomic configurations in GaN have been comparatively investigated using density functional theory (DFT) and molecular dynamics method with two representative potentials. The DIFT calculations show that the relaxation of vacancies is generally small, but the relaxation around antisite defects is large. The N interstitials, starting from any possible configurations, eventually relax into a N+-N < 1 1(2) over bar 0 > split interstitial. In the case of Ga interstitials, the most stable configuration is a Ga octahedral interstitial, but the Ga+-Ga < 1 1(2) over bar 0 > split interstitial can bridge the gap between non-bounded Ga atoms. The formation energies of vacancies and antisite defects obtained using the Stillinger-Weber potential (SW) are in reasonable agreement with those obtained by DIFT calculations, whereas the Tersoff-Brenner (TB) potential better describes the behavior of N interstitials. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gao, F (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM fei.gao@pnl.gov; eric.bylaska@pnl.gov; bill.weber@pnl.gov RI Weber, William/A-4177-2008; Gao, Fei/H-3045-2012 OI Weber, William/0000-0002-9017-7365; NR 14 TC 0 Z9 0 U1 0 U2 3 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-960-1 J9 MATER SCI FORUM PY 2005 VL 475-479 BP 3087 EP 3090 PN 1-5 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BBR99 UT WOS:000227494703128 ER PT S AU Meco, H Napolitano, RE AF Meco, H Napolitano, RE BE Zhong, ZY Saka, H Kim, TH Holm, EA Han, YF Xie, XS TI Upper-bound velocity limit for free-jet melt spinning SO PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 5th Pacific Rim International Conference on Advanced Materials and Processing CY NOV 02-05, 2004 CL Beijing, PEOPLES R CHINA SP Chinese Soc Met, Japan Inst Met, Korea Inst Met & Mat, Minerals, Met & Mat Soc DE melt spinning; rapid solidification; amorphous metals; melt-pool behavior AB The upper bound for the production of uniform amorphous ribbons during free-jet melt spinning is predicted by coupling a mass balance condition for the melt-pool with a simple boundary layer model for momentum transfer. The relationships between melt-pool length, ribbon thickness and wheel speed are investigated, and a criterion is developed for the onset of unsteady melt-pool behavior, which has previously been associated with increased surface roughness, porosity, and the formation of crystalline phases at high wheel speeds. C1 Iowa State Univ, US DOE, Ames, IA USA. RP Meco, H (reprint author), Iowa State Univ, US DOE, 104 Wilhelm Hall, Ames, IA USA. EM hmeco@iastate.edu; ralphn@iastate.edu NR 4 TC 0 Z9 0 U1 1 U2 2 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-960-1 J9 MATER SCI FORUM PY 2005 VL 475-479 BP 3371 EP 3376 PN 1-5 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BBR99 UT WOS:000227494704007 ER PT S AU Joo, HD Kim, JS Bark, CW Kim, JY Koo, YM Tamura, N AF Joo, HD Kim, JS Bark, CW Kim, JY Koo, YM Tamura, N BE Zhong, ZY Saka, H Kim, TH Holm, EA Han, YF Xie, XS TI Microdiffraction study of polycrystalline copper during uniaxial tension deformation using a synchrotron x-ray source SO PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 5th Pacific Rim International Conference on Advanced Materials and Processing CY NOV 02-05, 2004 CL Beijing, PEOPLES R CHINA SP Chinese Soc Met, Japan Inst Met, Korea Inst Met & Mat, Minerals, Met & Mat Soc DE microdiffraction; tensile axis rotation; polycrystal; local deformation; slip system AB In-situ measurement of local orientation and strain Has Been carried out for a copper-polycrystals under a uniaxial loading using a synchrotron x-ray microdiffraction method at the Advanced Light Source. The heterogeneities of deformation-induced microstructure within single grains were observed. There were differences in the selection of simultaneously acting slip systems among neighboring volume elements within a grain. C1 POSTECH, Dept Mat Sci & Engn, Pohang 790784, South Korea. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Joo, HD (reprint author), POSTECH, Dept Mat Sci & Engn, Pohang 790784, South Korea. EM matter@postech.ac.kr; jupiter@postech.ac.kr; koo@postech.ac.kr; ntamura@lbl.gov OI Bark, Chung Wung/0000-0002-9394-4240 NR 6 TC 0 Z9 0 U1 0 U2 0 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-960-1 J9 MATER SCI FORUM PY 2005 VL 475-479 BP 4149 EP 4152 PN 1-5 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BBR99 UT WOS:000227494704190 ER PT B AU Yang, WC Yeung, ES Schmerr, MJ Bodemer, W AF Yang, WC Yeung, ES Schmerr, MJ Bodemer, W BE Kitamoto, T TI Detection of the prion protein in a liquid phase capture assay using magnetic beads coupled to protein A SO Prions: Food and Drug Safety LA English DT Proceedings Paper CT International Symposium of Prion Diseases for Food and Drug Safety CY OCT 31-NOV 02, 2004 CL Sendai, JAPAN SP Japan Intractable Dis Res Fdn C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Yang, WC (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG TOKYO PI TOKYO PA 37-3, HONGO 3-CHOME BONKYO-KU, TOKYO, 113, JAPAN BN 4-431-25539-7 PY 2005 BP 199 EP 200 DI 10.1007/4-431-29402-3_27 PG 2 WC Biochemistry & Molecular Biology; Public, Environmental & Occupational Health; Infectious Diseases; Clinical Neurology; Neurosciences SC Biochemistry & Molecular Biology; Public, Environmental & Occupational Health; Infectious Diseases; Neurosciences & Neurology GA BCY14 UT WOS:000231843000027 ER PT J AU Dobson, I Carreras, BA Newman, DE AF Dobson, I Carreras, BA Newman, DE TI A loading-dependent model of probabilistic cascading failure SO PROBABILITY IN THE ENGINEERING AND INFORMATIONAL SCIENCES LA English DT Article ID RANDOM MAPPINGS; DISTRIBUTIONS; BLACKOUTS; SECURITY; SERIES AB We propose an analytically tractable model of loading-dependent cascading failure that captures some of the salient features of large blackouts of electric power transmission systems. This leads to a new application and derivation of the quasibinomial distribution and its generalization to a saturating form with an extended parameter range. The saturating quasibinomial distribution of the number of failed components has a power-law region at a critical loading and a significant probability of total failure at higher loadings. C1 Univ Wisconsin, Dept Elect & Comp Engn, Madison, WI 53706 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Alaska, Dept Phys, Fairbanks, AK 99775 USA. RP Dobson, I (reprint author), Univ Wisconsin, Dept Elect & Comp Engn, Madison, WI 53706 USA. EM dobson@engr.wisc.edu; carrerasba@ornl.gov; ffden@uaf.edu RI Dobson, Ian/C-3989-2008 OI Dobson, Ian/0000-0001-7018-5475 NR 33 TC 120 Z9 140 U1 1 U2 10 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4211 USA SN 0269-9648 J9 PROBAB ENG INFORM SC JI Probab. Eng. Inform. Sci. PY 2005 VL 19 IS 1 BP 15 EP 32 PG 18 WC Engineering, Industrial; Operations Research & Management Science; Statistics & Probability SC Engineering; Operations Research & Management Science; Mathematics GA 880QR UT WOS:000225804800002 ER PT J AU Dobson, I Carreras, BA Lynch, VE Nkei, B Newman, DE AF Dobson, I Carreras, BA Lynch, VE Nkei, B Newman, DE TI Estimating failure propagation in models of cascading blackouts SO PROBABILITY IN THE ENGINEERING AND INFORMATIONAL SCIENCES LA English DT Article; Proceedings Paper CT 8th International Conference on Probabilistic Methods Applied to Power Systems CY SEP 12-16, 2004 CL Iowa State Univ, Ames, IA HO Iowa State Univ ID SECURITY; DYNAMICS AB We compare and test statistical estimates of failure propagation in data from versions of a probabilistic model of loading-dependent cascading failure and a power system blackout model of cascading transmission line overloads. The comparisons suggest mechanisms affecting failure propagation and are an initial step toward monitoring failure propagation from practical system data. Approximations to the probabilistic model describe the forms of probability distribution of cascade sizes. C1 Univ Wisconsin, ECE Dept, Madison, WI 53706 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Alaska, Dept Phys, Fairbanks, AK 99775 USA. RP Dobson, I (reprint author), Univ Wisconsin, ECE Dept, Madison, WI 53706 USA. EM dobson@engr.wisc.edu; carrerasba@ornl.gov; ffden@uaf.edu RI Dobson, Ian/C-3989-2008; Lynch, Vickie/J-4647-2012 OI Dobson, Ian/0000-0001-7018-5475; Lynch, Vickie/0000-0002-5836-7636 NR 20 TC 19 Z9 21 U1 0 U2 4 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4211 USA SN 0269-9648 J9 PROBAB ENG INFORM SC JI Probab. Eng. Inform. Sci. PY 2005 VL 19 IS 4 BP 475 EP 488 PG 14 WC Engineering, Industrial; Operations Research & Management Science; Statistics & Probability SC Engineering; Operations Research & Management Science; Mathematics GA 972GQ UT WOS:000232442700006 ER PT B AU Lo, C Hinnerichs, T Hales, J AF Lo, Chi Hinnerichs, Terry Hales, Jason GP ASME TI Assessment of efficiency for a hybrid explicit/implicit code simulation of a multiple impact crash scenario SO Proceedings of IMECE 2005: Engineering/Technology Management LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div AB Sandia National Laboratories has developed a new explicit nonlinear transient dynamic finite element code called Presto and an associated implicit code called Adagio. This paper describes a process used to assess the ability and efficiency for sharing the computational workload of a multiple impact crash simulation between the explicit (Presto) and the implicit (Adagio) codes to minimize computation time. A numeric example of this hybrid simulation process is given that applies to a dynamic beam impact scenario. Results from simulations using each code will be compared with the hybrid simulation and discussed. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Lo, C (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. OI Hales, Jason/0000-0003-0836-0476 NR 4 TC 3 Z9 3 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4230-4 PY 2005 BP 381 EP 386 PG 6 WC Engineering, Multidisciplinary; Engineering, Mechanical SC Engineering GA BFM61 UT WOS:000243097500047 ER PT B AU Garimella, RV Dyadechko, V Swartz, BK Shashkov, MJ AF Garimella, RV Dyadechko, V Swartz, BK Shashkov, MJ BE Hanks, BW TI Interface reconstruction in multi-fluid, multi-phase flow simulations SO Proceedings of the 14th International Meshing Roundtable LA English DT Proceedings Paper CT 14th International Meshing Roundtable Meeting CY SEP 11-14, 2005 CL San Diego, CA ID LEVEL SET METHOD; TRACKING AB An advanced Volume-of-Fluid or VOF procedure for locally conservative reconstruction of multi-material interfaces based on volume fraction information in cells of an unstructured mesh is presented in this paper. The procedure employs improved neighbor definitions and topological consistency checks of the interface for computing a more accurate interface approximation. Comparison with previously published results for test problems involving severe deformation of the materials (such as vortex-in-a-box problem) show that this procedure produces more accurate results and reduces the "numerical surface tension" typically seen in VOF methods. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Garimella, RV (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 11 Z9 11 U1 0 U2 3 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-25137-5 PY 2005 BP 19 EP 32 DI 10.1007/3-540-29090-7_2 PG 14 WC Mathematics, Applied SC Mathematics GA BDH11 UT WOS:000233560500002 ER PT B AU Lipnikov, K Vassilevski, Y AF Lipnikov, K Vassilevski, Y BE Hanks, BW TI On discrete boundaries and solution accuracy in anisotropic adaptive meshing SO Proceedings of the 14th International Meshing Roundtable LA English DT Proceedings Paper CT 14th International Meshing Roundtable Meeting CY SEP 11-14, 2005 CL San Diego, CA ID OPTIMIZATION C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lipnikov, K (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RI Vassilevski, Yuri/A-6068-2016 NR 16 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-25137-5 PY 2005 BP 313 EP 324 PG 12 WC Mathematics, Applied SC Mathematics GA BDH11 UT WOS:000233560500019 ER PT B AU Verma, CS Fischer, PF Lee, SE Loth, F AF Verma, CS Fischer, PF Lee, SE Loth, F BE Hanks, BW TI An all-hex meshing strategy for bifurcation geometries in vascular flow simulation SO Proceedings of the 14th International Meshing Roundtable LA English DT Proceedings Paper CT 14th International Meshing Roundtable Meeting CY SEP 11-14, 2005 CL San Diego, CA AB We develop an automated all-hex meshing strategy for bifurcation geometries arising in subject-specific computational hemodynamics modeling. The key components of our approach are the use of a natural coordinate system, derived from solutions to Laplace's equation, that follows the tubular vessels (arteries, veins, or grafts) and the use of a tripartitioned-based mesh topology that leads to balanced high-quality meshes in each of the branches. The method is designed for situations where the required number of hexahedral elements is relatively small (similar to 1000-4000), as is the case when spectral elements are employed in simulations at transitional Reynolds numbers or when finite elements are employed in viscous dominated regimes. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Verma, CS (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 21 TC 7 Z9 7 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-25137-5 PY 2005 BP 363 EP 375 DI 10.1007/3-540-29090-7_22 PG 13 WC Mathematics, Applied SC Mathematics GA BDH11 UT WOS:000233560500022 ER PT B AU Staten, ML Owen, SJ Blacker, TD AF Staten, ML Owen, SJ Blacker, TD BE Hanks, BW TI Unconstrained paving & plastering: A new idea for all hexahedral mesh generation SO Proceedings of the 14th International Meshing Roundtable LA English DT Proceedings Paper CT 14th International Meshing Roundtable Meeting CY SEP 11-14, 2005 CL San Diego, CA DE mesh generation; hexahedra; plastering; sweeping; paving ID ALGORITHM AB Unconstrained Plastering is a new algorithm with the goal of generating a conformal all-hexahedral mesh on any solid geometry assembly. Paving[1] has proven reliable for quadrilateral meshing on arbitrary surfaces. However, the 3D corollary, Plastering [2][3][4][5], is unable to resolve the unmeshed center voids due to being over-constrained by a pre-existing boundary mesh. Unconstrained Plastering attempts to leverage the benefits of Paving and Plastering, without the over-constrained nature of Plastering. Unconstrained Plastering uses advancing fronts to inwardly project unconstrained hexahedral layers from an unmeshed boundary. Only when three layers cross, is a hex element formed. Resolving the final voids is easier since closely spaced, randomly oriented quadrilaterals do not over-constrain the problem. Implementation has begun on Unconstrained Plastering, however, proof of its reliability is still forthcoming. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Staten, ML (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 27 TC 18 Z9 18 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-25137-5 PY 2005 BP 399 EP 416 DI 10.1007/3-540-29090-7_24 PG 18 WC Mathematics, Applied SC Mathematics GA BDH11 UT WOS:000233560500024 ER PT B AU Nakajima, H Kutter, BL Ginn, TR Chang, DP Marino, MA AF Nakajima, H. Kutter, B. L. Ginn, T. R. Chang, D. P. Marino, M. A. GP MILLPRESS TI An experimental study of LNAPL lens formation using a centrifuge SO Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering, Vols 1-5: GEOTECHNOLOGY IN HARMONY WITH THE GLOBAL ENVIRONMENT LA English DT Proceedings Paper CT 16th International Conference on Soil Mechanics and Geotechnical Engineering CY 2005 CL Osaka, JAPAN SP Int Soc Soil Mech & Geotech Engn, Japanese Geotech Soc ID TRANSPORT AB Understanding movement of light non-aqueous phase liquids (LNAPLs) in a subsurface environment is important for effective remediation and recovery. Processes involving LNAPL formation of a lens shaped plume on the groundwater table is of particular interest since the LNAPL lens can act as a long-term source of groundwater contamination. In this study, two-dimensional centrifuge model tests were carried out to simulate the movement of an LNAPL plume in the vadose zone and to investigate how LNAPL accumulates and forms a lens-shaped plume above the unconfined aquifer. The model represents a point spill of an LNAPL from approximately 1 meter above the water table in prototype scale. We present a description of the centrifuge test system we developed and the results obtained from image analysis. The comparison of the centrifuge tests and the numerical simulations showed good overall agreement especially in the plume shape and propagation pattern. The shape of the LNAPL plume was observed to elongate when a sloping groundwater table was simulated in the model tests. C1 Idaho Natl Lab, Geosci Res Dept, Idaho Falls, ID 83401 USA. RP Nakajima, H (reprint author), Idaho Natl Lab, Geosci Res Dept, Idaho Falls, ID 83401 USA. NR 5 TC 1 Z9 1 U1 0 U2 2 PU MILLPRESS SCIENCE PUBLISHERS PI ROTTERDAM PA PO BOX 84118, 3009 CC ROTTERDAM, NETHERLANDS BN 978-90-5966-027-4 PY 2005 BP 2425 EP 2428 PG 4 WC Engineering, Geological; Soil Science SC Engineering; Agriculture GA BGG08 UT WOS:000246615103114 ER PT B AU Mei, JS Shadle, LJ Yue, P Monazam, ER AF Mei, Joseph S. Shadle, Lawrence J. Yue, Paul Monazam, Esmail R. GP ASME TI Hydrodynamics of a transport reactor operating in dense suspension upflow conditions for coal combustion applications SO Proceedings of the 18th International Conference on Fluidized Bed Combustion LA English DT Proceedings Paper CT 18th International Conference on Fluidized Bed Combustion CY MAY 22-25, 2005 CL Toronto, CANADA SP ASME, CANMET Energy Technol Ctr Ottawa, Alstom Power Inc, Austrian Energy & Environ AG, Greenfield Res ID FLUIDIZED-BED RISER; TRANSITION; TURBULENT AB A series of experiments were conducted in the 0.3-meter diameter, 15.45-m high cold flow circulating fluid bed (CFB) test facility at the National Energy Technology Laboratory (NETL) of the U. S. Department of Energy. Operation of the CFB demonstrated that high density conditions can be achieved throughout the entire riser with sufficiently high solid fluxes in a riser taller than what has been previously reported in the literature. Tests were conducted on Geldart type B, 60 mu m diameter, glass beads at two different gas velocities (5.1 and 7.8 m/s). The riser's axial solids fraction profile provided distinct characteristics that enabled us to differentiate between dense suspension upflow (DSU) and core annular flow regimes. The apparent solids holdup in the riser exceeded 7% when operating in DSU. A fiber optic probe was used to measure particle velocities near the wall 8.5 in above the solids entry. These measurements did not always record upward particle velocities when in DSU conditions. A number of possible reasons are identified and discussed. Solid fluxes greater than 250 kg/m(2)-s for 5.1 m/s and 350 kg/m(2)-s at 7.8 m/s appeared to be sufficient to achieve DSU conditions. The trend in the measured particle velocities near the wall was also consistent with these transitions. The transition from core annular conditions to DSU operations depended upon both gas velocity and solids flux and was in good agreement with an existing correlation found in the literature. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP Mei, JS (reprint author), US DOE, Natl Energy Technol Lab, 3601 Collins Ferry Rd, Morgantown, WV 26507 USA. OI Shadle, Lawrence/0000-0002-6283-3628 NR 11 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4698-9 PY 2005 BP 423 EP 431 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFM53 UT WOS:000243076700049 ER PT B AU Miers, SA Barna, GL Anderson, CL Blough, JR Inal, MK Ciatti, SA AF Miers, Scott A. Barna, Glen L. Anderson, Carl L. Blough, Jason R. Inal, M. Koray Ciatti, Stephen A. GP ASME TI A wireless microwave telemetry data transfer technique for reciprocating and rotating components SO Proceedings of the 2005 Fall Technical Conference of the ASME Internal Combustion Engine Division LA English DT Proceedings Paper CT Fall Technical Meeting of the ASME Internal Combustion Engine Division CY SEP 11-14, 2005 CL Ottawa, CANADA SP ASME, Internal Combust Engine Div AB Wireless microwave telemetry addresses the difficult issue of obtaining transducer outputs from reciprocating and rotating components through the use of advanced electronic components. This eliminates the requirements of a direct link between the transducer and the acquisition system. Accuracy of the transducer signal is maintained through the use of a double frequency modulation (FM) technique which provides temperature stability and a 20 point calibration of each, complete system. Multiple transmitters can be used for larger applications and multiple antennas can be used to improve the signal strength and reduce the possibility of dropouts. Examples of piston temperature and automotive torque converter measurements are provided, showing the effectiveness of the wireless measuring technique. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Miers, SA (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4736-5 PY 2005 BP 1 EP 9 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN83 UT WOS:000243375300001 ER PT B AU Ciatti, SA Miers, SA Ng, HK AF Ciatti, Stephen A. Miers, Scott A. Ng, Henry K. GP ASME TI Influence of EGR on soot/NOx production in a light-duty diesel engine SO Proceedings of the 2005 Fall Technical Conference of the ASME Internal Combustion Engine Division LA English DT Proceedings Paper CT Fall Technical Meeting of the ASME Internal Combustion Engine Division CY SEP 11-14, 2005 CL Ottawa, CANADA SP ASME, Internal Combust Engine Div AB A study to explore the effect of EGR upon combustion in a light-duty automotive style diesel engine was performed. The engine used in this study was a Mercedes 1.7L 4 cylinder, direct injected turbodiesel. with a common rail injection system. The engine was operated at 2500 RPM, 50% load, with constant rail pressure and injection duration. An endoscope imaging system built by AVL, called the VisioScopeTm, was used to acquire in-cylinder optical images of combustion events. These images were processed to extract soot radiation temperatures and soot volume fraction for each pixel. The results were compared to global engine measurements using piezo-electric pressure transducers, an emissions bench, and a scanning mobility particle sizer (SMPS) to characterize particulates. It was discovered that the optical data correlated well with the global measurements, allowing for in-depth analysis of the mechanisms of emissions formation at three different EGR levels (0%, 10%, 19%). Several conclusions were reached, including the correlation of soot radiation temperature with NO, production and the correlation of soot luminosity with engine-out PM. Each of these factors was determined as a function of EGR level. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Ciatti, SA (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. NR 9 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4736-5 PY 2005 BP 415 EP 423 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN83 UT WOS:000243375300045 ER PT B AU Edwards, KD Wagner, RM Theiss, TJ Daw, CS AF Edwards, K. Dean Wagner, Robert M. Theiss, Timothy J. Daw, C. Stuart GP ASME TI An approach for investigating adaptive control strategies to improve combustion stability under dilute operating conditions SO Proceedings of the 2005 Fall Technical Conference of the ASME Internal Combustion Engine Division LA English DT Proceedings Paper CT Fall Technical Meeting of the ASME Internal Combustion Engine Division CY SEP 11-14, 2005 CL Ottawa, CANADA SP ASME, Internal Combust Engine Div AB Dilute operation of internal combustion engines through lean fueling and/or high levels of exhaust gas recirculation (EGR) is frequently employed to increase fuel efficiency, reduce NOx emissions, and promote enhanced combustion modes such as HCCI. The maximum level of dilution is limited by the development of combustion instabilities that produce unacceptable levels of cycle-to-cycle combustion variability. These combustion instabilities are frequently stimulated by the nonlinear feedback associated with the residual and recirculated exhaust gases exchanged between successive cycles. However, with the application of adaptive control, it is possible to limit the severity of the combustion variability and regain efficiency and emission reduction benefits that would otherwise be lost. In order to better characterize the benefits of adaptive control, we have employed a two-zone phenomenological combustion model to simulate the onset of combustion instabilities under dilute operating conditions and illustrate the impact of these instabilities on emissions and fuel efficiency. The two-zone in-cylinder combustion model is coupled to a WAVE engine-simulation code, allowing rapid simulation of several hundred successive engine cycles with many external engine parametric effects included. By applying adaptive feedback control to the WAVE model, we demonstrate how mitigation of the extreme combustion events can result in improved efficiency and reduced emissions levels. We expect that this approach can be used to estimate the potential benefits of implementing adaptive control strategies on specific engine platforms to achieve further efficiency and emission-reduction gains. C1 Oak Ridge Natl Lab, Knoxville, TN 37932 USA. RP Edwards, KD (reprint author), Oak Ridge Natl Lab, 2360 Cherahala Blvd, Knoxville, TN 37932 USA. NR 16 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4736-5 PY 2005 BP 577 EP 584 PG 8 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN83 UT WOS:000243375300064 ER PT B AU Parks, JE Tassitano, J AF Parks, James E., II Tassitano, Jim GP ASME TI Natural gas partial oxidation and reforming for lean NOx trap catalysis regeneration SO Proceedings of the 2005 Fall Technical Conference of the ASME Internal Combustion Engine Division LA English DT Proceedings Paper CT Fall Technical Meeting of the ASME Internal Combustion Engine Division CY SEP 11-14, 2005 CL Ottawa, CANADA SP ASME, Internal Combust Engine Div AB Program goals for the Advanced Reciprocating Engine Systems (ARES) program of the Department of Energy include efficiency and environmental goals. Lean-bum natural gas engines offer higher efficiency than engines that operate with Stoichiometric air-to-fuel mixtures; however, the excess oxygen in the exhaust of lean engines makes NOx reduction with catalytic aftertreatment difficult. Thus, advancing efficiency via lean combustion results in challenges to meet environmental goals. The lean NOx trap catalyst technology is capable of reducing NOx in lean exhaust and, thereby, enables the potential for lean combustion to meet both efficiency and environmental goals. During lean NOx trap catalysis, NOx in oxygen-rich exhaust is trapped on the catalyst by alkali or alkaline earth-based sorbate materials; then, upon exposure to oxygen-depleted exhaust, the NOx is released and reduced to nitrogen in a process called regeneration. The regeneration process renews the catalyst for more NOx trapping; the cyclic process repeats at periods on the order of a minute. Oxygen depletion during regeneration is accomplished by temporarily operating the catalyst at rich air-to-fuel ratios; traditionally, a variety of methods have been utilized to achieve rich conditions for the catalyst. In this presentation, research of a lean NOx trap on a lean natural gas engine will be presented. Natural gas from the engine supply was used to provide the reductant for the lean NOx trap regeneration process. The natural gas is injected into the exhaust system where oxidation and reforming catalysts partially oxidize and/or reform the natural gas into reductants suitable for lean NOx trap regeneration. Studies of the natural gas oxidation and reforming processes and their relation to NOx reduction performance will be presented. C1 Oak Ridge Natl Lab, Knoxville, TN 37932 USA. RP Parks, JE (reprint author), Oak Ridge Natl Lab, 2360 Cherahala Blvd, Knoxville, TN 37932 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4736-5 PY 2005 BP 585 EP 593 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN83 UT WOS:000243375300065 ER PT B AU Tassitano, J Parks, JE AF Tassitano, Jim Parks, James E., II GP ASME TI Analysis of the rotating arc spark plug in a natural gas engine SO Proceedings of the 2005 Fall Technical Conference of the ASME Internal Combustion Engine Division LA English DT Proceedings Paper CT Fall Technical Meeting of the ASME Internal Combustion Engine Division CY SEP 11-14, 2005 CL Ottawa, CANADA SP ASME, Internal Combust Engine Div AB Large natural gas engines are durable and cost-effective generators of power for distributed energy applications. Fuel efficiency is an important aspect of distributed generation since operating costs associated with fuel consumption are the major component of energy cost on a life-cycle basis; furthermore, higher fuel efficiency results in lower CO, emissions. Leaner operation of natural gas engines can result in improved fuel efficiency; however, engine operation becomes challenging at leaner air-to-fuel ratios due to several factors. One factor in combustion control is ignition. At lean air-fuel mixtures, reliable and repeatable ignition is necessary to maintain consistent power production from the engine, and spark plug quality and durability play an important role in reliability of ignition. Here research of a novel spark plug design for lean natural gas engines is presented. The spark plug is an annular gap spark plug with a permanent magnet that produces a magnetic field that forces the spark to rotate during spark discharge. The rotating arc spark plug (RASP) has the potential to improve ignition system reliability and durability. In the study presented here, the RASP plug was operated in a small natural gas engine, and combustion stability (measured by the coefficient of variation of indicated mean effective pressure (IMEP)) was measured as a function of air-to-fuel ratio to characterize the ignition performance at lean mixtures. Comparisons were made to a standard J-plug spark plug. C1 Oak Ridge Natl Lab, Knoxville, TN 37932 USA. RP Tassitano, J (reprint author), Oak Ridge Natl Lab, 2360 Cherahala Blvd, Knoxville, TN 37932 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4736-5 PY 2005 BP 595 EP 599 PG 5 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN83 UT WOS:000243375300066 ER PT B AU Bihari, B Gupta, SB Sekar, RR Gingrich, J Smith, J AF Bihari, Bipin Gupta, Sreenath B. Sekar, Raj R. Gingrich, Jess Smith, Jack GP ASME TI Development of advanced laser ignition system for stationary natural gas reciprocating engines SO Proceedings of the 2005 Fall Technical Conference of the ASME Internal Combustion Engine Division LA English DT Proceedings Paper CT Fall Technical Meeting of the ASME Internal Combustion Engine Division CY SEP 11-14, 2005 CL Ottawa, CANADA SP ASME, Internal Combust Engine Div AB Laser ignition is considered the prime alternative to conventional coil based ignition for improving efficiency and simultaneously reducing NOx emissions in lean-bum natural gas fired stationary reciprocating engines. In this paper, Argonne's efforts towards the development of a viable laser ignition system are presented. The relative merits of various implementation strategies for laser based ignition are discussed. Finally, the performance improvements required for some of the components for successful field implementation are listed. Also reported are efforts to determine the relative merit of laser ignition over conventional Capacitance Discharge Ignition (CDI) ignition. Emissions and performance data of a large-bore single cylinder research engine are compared while running with laser ignition and the industry standard CDI system. It was primarily noticed that NOx emissions reduce by 50% under full load conditions with up to 65% reductions noticed under part load conditions. Also, the lean ignition limit was significantly extended and laser ignition improved combustion stability under all operating conditions. Other noticeable differences in combustion characteristics are also presented. Efforts wherein ignition was achieved while transmitting the high-power laser pulses through optical fibers showed performance improvements similar those achieved by using free-space laser ignition. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Bihari, B (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 0 Z9 0 U1 0 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4736-5 PY 2005 BP 601 EP 608 PG 8 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN83 UT WOS:000243375300067 ER PT B AU Flowers, DL Martinez-Frias, J Espinosa-Loza, F Killingsworth, N Aceves, SM Dibble, R Kristic, M Bining, A AF Flowers, Daniel L. Martinez-Frias, Joel Espinosa-Loza, Francisco Killingsworth, Nick Aceves, Salvador M. Dibble, Robert Kristic, Miroslav Bining, Avtar GP ASME TI Development and testing of a 6-cylinder HCCI engine for distributed generation SO Proceedings of the 2005 Fall Technical Conference of the ASME Internal Combustion Engine Division LA English DT Proceedings Paper CT Fall Technical Meeting of the ASME Internal Combustion Engine Division CY SEP 11-14, 2005 CL Ottawa, CANADA SP ASME, Internal Combust Engine Div AB This paper describes the technical approach for converting a Caterpillar 3406 natural gas spark ignited engine into HCCI mode. The paper describes all stages of the process, starting with a preliminary analysis that determined that the engine can be operated by preheating the intake air with a heat exchanger that recovers energy from the exhaust gases. This heat exchanger plays a dual role, since it is also used for starting the engine. For start-up, the heat exchanger is preheated with a natural gas burner. The engine is therefore started in HCCI mode, avoiding the need to handle the potentially difficult transition from SI or diesel mode to HCCI. The fueling system was modified by replacing the natural gas carburetor with a liquid petroleum gas (LPG) carburetor. This modification sets an upper limit for the equivalence ratio at phi similar to 0.4, which is ideal for HCCI operation and guarantees that the engine will not fail due to knock. Equivalence ratio can be reduced below 0.4 for low load operation with an electronic control valve. Intake boosting has been a challenge, as commercially available turbochargers are not a good match for the engine, due to the low HCCI exhaust temperature. Commercial introduction of HCCI engines for stationary power will therefore require the development of turbochargers designed specifically for this mode of operation. Considering that no appropriate off-the-shelf turbocharger for HCCI engines exists at this time, we are investigating mechanical supercharging options, which will deliver the required boost pressure (3 bar absolute intake) at the expense of some reduction in the output power and efficiency. An appropriate turbocharger can later be installed for improved performance when it becomes available or when a custom turbocharger is developed. The engine is now running in HCCI mode and producing power in an essentially naturally aspirated mode. Current work focuses on developing an automatic controller for obtaining consistent combustion in the 6 cylinders. The engine will then be tested for 1000 hours to demonstrate durability. This paper presents intermediate progress towards development of an HCCI engine for stationary power generation and next steps towards achieving the project goals. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Flowers, DL (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI aceves, salvador/G-9052-2011 OI aceves, salvador/0000-0001-5687-7256 NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4736-5 PY 2005 BP 643 EP 651 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN83 UT WOS:000243375300071 ER PT B AU Huang, CF Tiee, M Forst, CV AF Huang, CF Tiee, M Forst, CV GP IEEE TI Pathway optimization of biological drug response networks SO PROCEEDINGS OF THE 2005 IEEE SYMPOSIUM ON COMPUTATIONAL INTELLIGENCE IN BIOINFORMATICS AND COMPUTATIONAL BIOLOGY LA English DT Proceedings Paper CT 2nd IEEE Symposium on Computational Intelligence in Bioformatics and Computational Biology CY NOV 14-15, 2005 CL La Jolla, CA SP IEEE Computat Intelligence Soc ID MYCOBACTERIUM-TUBERCULOSIS; INSIGHTS; SYNTHASE; GENOMES AB One of the major challenges in systems biology today is to devise generally robust methods of interpreting data concerning the expression levels of the genes in an organism in a way that will shed light on the complex relationships between multiple genes and their products. The ability to better understand and predict the structures and actions of complex biological systems is of significant importance to modern drug discovery as well as our understanding of the mechanisms behind an organism's ability to react to its environment. In this paper we present a study for robust biological pathway construction through genetic algorithms. The platform is based on the construction of biological networks given different sets of interaction information and the optimization of sub-networks constrained by the gene expression data. As an application, expression data of drug response in M. tuberculosis is used to build generic response subnetworks. Subnetworks are then compared to identify the essential key components that are common to different networks. We are thus able to identify essential nodes in specific drug response. We expect that this approach will provide robust prediction of response networks and accelerate target identification for drug development in the future. C1 Los Alamos Natl Lab, Div Biosci, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Biosci, POB 1663, Los Alamos, NM 87545 USA. EM cfhuang@lanl.gov; tieem@lanl.gov; chris@lanl.gov NR 34 TC 1 Z9 1 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-9387-2 PY 2005 BP 82 EP 89 PG 8 WC Biochemical Research Methods; Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Biochemistry & Molecular Biology; Computer Science GA BDU91 UT WOS:000235518600012 ER PT B AU Klett, GM Gupta, S Bihari, B Sekar, R AF Klett, Gregory M. Gupta, Sreenath Bihari, Bipin Sekar, Raj GP ASME TI Ignition characteristics of methane-air mixtures at elevated temperatures and pressures SO Proceedings of the 2005 Spring Technical Conference of the ASME Internal Combustion Engine Division LA English DT Proceedings Paper CT Spring Technical Conference of the ASME-Internal-Combustion-Engine-Division CY APR 05-07, 2005 CL Chicago, IL SP ASME, Internal Combust Engine Div AB Lean operation of natural gas fired reciprocating engines has been the preferred mode of operation as it allows low NO, emissions and simultaneous high overall efficiencies. In such engines, the operation point is often close to where the ignition boundary and the knock limiting boundary cross-over. While knocking is, to a large extent, limited by engine design, ignition of lean-mixtures is limited by the mode of ignition. Since significant benefits can be achieved by extending the lean-ignition limits, many groups have been researching alternate ways to achieve ignition reliably. One of the methods, laser ignition, appears promising as it achieves ignition at high pressures and under lean conditions relatively easily. However, most of the current knowledge about laser ignition is based on measurements performed at room temperature. In this paper, ignition studies on methane-air mixtures under in-cylinder conditions are presented. A Rapid Compression Machine (RCM) was designed to reproduce typical in-cylinder conditions of high temperature (similar to 490 degrees C) and pressure (similar to 77 Bar) at the time of ignition. Experiments were performed comparing conventional coil based ignition (CDI) and laser ignition on methane-air mixtures while varying pressure and equivalence ratio systematically. It was observed that substantial gains are possible with the use of laser ignition as it extends the lean-ignition limit to the flammability limit, i.e., phi = 0.5. On the other hand, conventional CDI ignition could not ignite mixtures leaner than phi = 0.6. Also, faster combustion times and shorter ignition delays were observed in the case of laser ignition. Through scans performed for minimum required laser energies (MIZE), it was noted that the measured values were substantially higher than those reported elsewhere. However, the trends of these values indicate that a laser ignition system designed for phi = 0.65 will successfully operate under all other equivalence ratios of a typical lean-burn engine. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Klett, GM (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4184-7 PY 2005 BP 281 EP 287 PG 7 WC Engineering, Mechanical SC Engineering GA BFM51 UT WOS:000243075700030 ER PT B AU Macal, CM North, MJ AF Macal, CM North, MJ BE Kuhl, ME Steiger, NM Armstrong, FB Joines, JA TI Tutorial on agent-based modeling and simulation SO Proceedings of the 2005 Winter Simulation Conference, Vols 1-4 LA English DT Proceedings Paper CT 2005 Winter Simulation Conference (WSC 05) CY DEC 04-07, 2005 CL Orlando, FL SP Amer Stat Assoc, ACM SIGSIM, IEEE Comp Soc, IEEE SMC, Inst Ind Engineers, INFORMS SIM, NIST, Soc Modeling & Simulat Int ID ECONOMICS AB Agent-based modeling and simulation (ABMS) is a new approach to modeling systems comprised of autonomous, interacting agents. ABMS promises to have far-reaching effects on the way that businesses use computers to support decision-making and researchers use electronic laboratories to support their research. Some have gone so far as to contend that ABMS is a third way of doing science besides deductive and inductive reasoning. Computational advances have made possible a growing number of agent-based applications in a variety of fields. Applications range from modeling agent behavior in the stock market and supply chains, to predicting the spread of epidemics and the threat of bio-warfare, from modeling consumer behavior to understanding the fall of ancient civilizations, to name a few. This tutorial describes the theoretical and practical foundations of ABMS, identifies toolkits and methods for developing ABMS models, and provides some thoughts on the relationship between ABMS and traditional modeling techniques. C1 Argonne Natl Lab, Ctr Complex Adapt Agent Syst Simulat CAS2, Decis & Informat Sci Div, Argonne, IL 60439 USA. RP Macal, CM (reprint author), Argonne Natl Lab, Ctr Complex Adapt Agent Syst Simulat CAS2, Decis & Informat Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 51 TC 84 Z9 87 U1 2 U2 23 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-9519-0 PY 2005 BP 2 EP 15 DI 10.1109/WSC.2005.1574234 PG 14 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Operations Research & Management Science SC Computer Science; Operations Research & Management Science GA BDY77 UT WOS:000236253400001 ER PT B AU Nutaro, J AF Nutaro, J BE Kuhl, ME Steiger, NM Armstrong, FB Joines, JA TI Constructing multi-point discrete event integration schemes SO Proceedings of the 2005 Winter Simulation Conference, Vols 1-4 LA English DT Proceedings Paper CT 2005 Winter Simulation Conference (WSC 05) CY DEC 04-07, 2005 CL Orlando, FL SP Amer Stat Assoc, ACM SIGSIM, IEEE Comp Soc, IEEE SMC, Inst Ind Engineers, INFORMS SIM, NIST, Soc Modeling & Simulat Int ID SIMULATION; SYSTEMS AB The systematic study of discrete event numerical integration schemes can be greatly aided by an understanding of their general form. This paper describes the structure of DEVS models that can be used to construct multi-point discrete event integration methods. The structure is shown to be sufficient for describing two known methods. The utility of the structure is illustrated by the construction of a new, second order accurate, multi-point discrete event integrator. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Nutaro, J (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. OI Nutaro, James/0000-0001-7360-2836 NR 11 TC 3 Z9 3 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-9519-0 PY 2005 BP 267 EP 273 DI 10.1109/WSC.2005.1574260 PG 7 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Operations Research & Management Science SC Computer Science; Operations Research & Management Science GA BDY77 UT WOS:000236253400027 ER PT B AU Sanders, RL Lake, JE AF Sanders, RL Lake, JE BE Kuhl, ME Steiger, NM Armstrong, FB Joines, JA TI Training first responders to nuclear facilities using 3-D visualization technology SO Proceedings of the 2005 Winter Simulation Conference, Vols 1-4 LA English DT Proceedings Paper CT 2005 Winter Simulation Conference (WSC 05) CY DEC 04-07, 2005 CL Orlando, FL SP Amer Stat Assoc, ACM SIGSIM, IEEE Comp Soc, IEEE SMC, Inst Ind Engineers, INFORMS SIM, NIST, Soc Modeling & Simulat Int AB The development of an advanced visualization and simulation tool for first responder exercises and education is presented. This tool exploits cutting edge computer graphics, physics-based effects modeling, virtual reality, and gaming technologies to establish a system that can eventually be used for the administrative planning and training of first responders in homeland security, homeland defense, and combating terrorism communities. C1 Oak Ridge Natl Lab, Computat Sci & Engn Div, Oak Ridge, TN 37923 USA. RP Sanders, RL (reprint author), Oak Ridge Natl Lab, Computat Sci & Engn Div, Bldg 5700,Mail Stop 6085,1 Bethel Valley Rd, Oak Ridge, TN 37923 USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-9519-0 PY 2005 BP 914 EP 918 DI 10.1109/WSC.2005.1574339 PG 5 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Operations Research & Management Science SC Computer Science; Operations Research & Management Science GA BDY77 UT WOS:000236253401032 ER PT B AU Jones, DA Turnquist, MA Nozick, LK AF Jones, DA Turnquist, MA Nozick, LK BE Kuhl, ME Steiger, NM Armstrong, FB Joines, JA TI Simulation of imperfect information in vulnerability modeling for infrastructure facilities SO Proceedings of the 2005 Winter Simulation Conference, Vols 1-4 LA English DT Proceedings Paper CT 2005 Winter Simulation Conference (WSC 05) CY DEC 04-07, 2005 CL Orlando, FL SP Amer Stat Assoc, ACM SIGSIM, IEEE Comp Soc, IEEE SMC, Inst Ind Engineers, INFORMS SIM, NIST, Soc Modeling & Simulat Int AB A model of malicious intrusions in infrastructure facilities is developed that uses a network representation of the system structure together with Markov models of intruder progress and strategy. Simulation is used to analyze varying levels of imperfect information on the part of the intruders in planning their attacks. This provides an explicit mechanism to estimate the probability of successful breaches of physical security, and to evaluate potential means to reduce that probability. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jones, DA (reprint author), Sandia Natl Labs, POB 5800 MS 1138, Albuquerque, NM 87185 USA. NR 7 TC 1 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-9519-0 PY 2005 BP 965 EP 971 DI 10.1109/WSC.2005.1574346 PG 7 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Operations Research & Management Science SC Computer Science; Operations Research & Management Science GA BDY77 UT WOS:000236253401039 ER PT B AU Goodman, M AF Goodman, Maury GP Tata Inst Fundamental Res TI Neutrinos and dark matter SO Proceedings of the 29th International Cosmic Ray Conference, Vol 10 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys ID SEARCH AB There has been incredible progress in the last few years in the understanding of the neutrino, and the 2005 International Cosmic Ray Conference in Mumbai included many presentations about solar, atmospheric, reactor and accelerator neutrino experiments. At the same time, a growing community of cosmic ray physicists are preparing to study high energy neutrino astronomy with large neutrino telescopes which are being built. Searches which are still negative continue for other phenomena, such as magnetic monopoles and Weakly Interacting Massive Particles. This rapporteur report will survey these developments. C1 Argonne Natl Lab, High Energy Phys Div, Argonne, IL 60439 USA. RP Goodman, M (reprint author), Argonne Natl Lab, High Energy Phys Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 73 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 303 EP 316 PG 14 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO88 UT WOS:000243522500021 ER PT B AU Sinnis, G AF Sinnis, Gus CA Milagro Collaboration GP Tata Institute Fundamental Res TI Detection of TeV gamma ray emission from the Galactic plane SO Proceedings of the 29th International Cosmic Ray Conference, Vol 4: OG 2.1, 2.2 & 2.3 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys ID AIR-SHOWER ARRAY; SEARCH AB Diffuse gamma rays produced by interactions of cosmic rays with matter in the Galaxy have previously been detected up to 30 GeV by the EGRET instrument. Here we report the first detection of a TeV gamma-ray flux from the Galactic plane by Milagro. An excess with a significance of 4.5 standard deviations is observed from a region of Galactic longitude 1 is an element of(40 degrees,100 degrees) and latitude vertical bar b vertical bar < 5 degrees. The measured integral gamma-ray flux is phi(> 3.5 TeV) = (6.4 +/- 1.4 +/- 2.1)x10(-11) cm(-2) sec(-1) sr(-1). This flux is consistent with an extrapolation of the EGRET spectrum between 1 and 30 GeV in this region of the Galaxy. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sinnis, G (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 81 EP 84 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO98 UT WOS:000243524200022 ER PT B AU Dingus, BL AF Dingus, Brenda L. CA Milagro Collaboration GP Tata Institute Fundamental Res TI TeV observations of EGRET unidentified sources SO Proceedings of the 29th International Cosmic Ray Conference, Vol 4: OG 2.1, 2.2 & 2.3 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys ID MILAGRO AB Most of the sources detected by EGRET are not yet identified with astrophysical objects known at longer wavelengths. Some of these sources are variable and some of them may be extended. Milagro, a large field of view (similar to 2 sr), high (> 90%) duty factor, TeV gamma-ray observatory is ideal for searching for TeV emission from these sources. There are 68 unidentified EGRET sources within the declination band from. 5 to 70 degrees to which Milagro has sufficient exposure. Of these 68 sources, 29 are within 10 degrees of the Galactic plane. TeV fluxes for all 68 sources are constrained by the Milagro observations, and one of these sources, 3EG0520+2556, is consistent with one of the most significant excesses in the Milagro survey of the entire declination band from 5 to 70 degrees. The Milagro excess at this location shows evidence of being extended and when fit to a Gaussian the sigma is 0.8 +/- 0.4 degrees. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dingus, BL (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. OI Dingus, Brenda/0000-0001-8451-7450 NR 6 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 475 EP 478 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO98 UT WOS:000243524200122 ER PT B AU Dingus, BL AF Dingus, Brenda L. CA Milagro Collaboration GP Tata Institute Fundamental Res TI Search for TeV emission from galaxy clusters SO Proceedings of the 29th International Cosmic Ray Conference, Vol 4: OG 2.1, 2.2 & 2.3 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys ID RADIATION AB Galaxy clusters are predicted to be emitters of high energy gamma rays due to the relativistic particles accelerated by merger and accretion shocks. The gamma rays are produced either by inverse Compton scattering of relativistic electrons or by high energy proton cascades due to p-p collisions. Some predictions of TeV fluxes from clusters such as Coma are near the sensitivity of current detectors. In this paper we. report upper limits for TeV gamma-ray emission from clusters using data from the Milagro gamma-ray observatory. Milagro is a unique TeV gamma-ray observatory, located in the mountains above Los Alamos, NM, that has a similar to 2 sr field of view and > 90% duty factor, making it ideal for surveying the sky for new classes of TeV astrophysical sources. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dingus, BL (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. OI Dingus, Brenda/0000-0001-8451-7450 NR 7 TC 0 Z9 0 U1 0 U2 1 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 479 EP 482 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO98 UT WOS:000243524200123 ER PT B AU Sinnis, G AF Sinnis, G. CA HAWC collaboration GP Tata Institute Fundamental Res TI HAWC - A bird's eye view of the extreme universe SO Proceedings of the 29th International Cosmic Ray Conference, Vol 5: OG 2.5, 2.6 & 2.7 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys AB Recent progress in the field of very-high-energy (> 100 GeV) gamma-ray astrophysics has been remarkable. With the advent of the H.E.S.S. telescope and the upcoming launch of GLAST we can look forward to an even more exciting future. However there is a problem with the current suite of instruments planned to cover the highest energy range. Though capable of remarkable sensitivity, air Cherenkov telescopes a re best suited to study individual sources or perform surveys over a limited area of the sky. While GLAST will detect several thousand sources and the objects that emit VHE gamma rays are generally variable, no all-sky monitor in the VHE energy region is planned. Here we present plans for an all-sky VHE instrument with dramatically improved sensitivity over the current generation of such instruments. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sinnis, G (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 5 TC 0 Z9 0 U1 1 U2 1 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 435 EP 438 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO99 UT WOS:000243524500110 ER PT B AU Sinnis, G AF Sinnis, G. CA HiRes Collaboration GP Tata Inst Fundamental Res TI Search for a Galactic enhancement of the ultra-high-energy cosmic rays using the HiRes stereo data SO Proceedings of the 29th International Cosmic Ray Conference Vol 7: HE 1.4 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys ID FLYS EYE AB Previous reports from the AGASA collaboration have indicated evidence for an enhancement from the Galactic plane in a relatively narrow energy band between 1 and 2 EeV. If correct this would be the most direct evidence to date for Galactic sources of ultra-high-energy cosmic rays. Analysis of similar to 4.3 years of stereo data taken with the High Resolution Fly's Eye Experiment (HiRes) shows no indication of an enhancement from the direction corresponding to the Galactic plane. Analysis of the entire dataset also shows no indication of an enhancement from the Galactic plane. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sinnis, G (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 377 EP 380 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO91 UT WOS:000243522800096 ER PT B AU Chirkin, D AF Chirkin, D. CA IceCube Collaboration GP Tata Inst Fundamental Res TI IceCube: Initial performance SO Proceedings of the 29th International Cosmic Ray Conference Vol 8: HE 1.5 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys AB The first new optical sensors of the IceCube neutrino observatory - 60 on one string and 16 in four IceTop stations - were deployed during the austral summer of 2004-05. We present an analysis of the first few months of data collected by this configuration. We demonstrate that hit times are determined across the whole array to a precision of a few nanoseconds. We also look at coincident IceTop and deep-ice events and verify the capability to reconstruct muons with a single string. Muon events are compared to a simulation. The performance of the sensors meets or exceeds the design requirements. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Chirkin, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 303 EP 306 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO92 UT WOS:000243522900077 ER PT B AU Reil, K Huntemeyer, P AF Reil, K. Huntemeyer, P. CA FLASH Collaboration GP Tata Inst Fundamental Res TI The FLASH thin target experiment: Total and spectrally resolved air fluorescence yield measurement using 28.5 GeV electrons SO Proceedings of the 29th International Cosmic Ray Conference Vol 8: HE 1.5 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys ID PHOTON YIELDS AB To reduce the systematic uncertainty of experiments using the air fluorescence technique we have measured the fluorescence yield (photons/meter/charged particle) of 28.5 GeV electrons in air and nitrogen. The FLuorescence in Air from SHowers (FLASH) experiment was performed, in the final focus test beam (FFTB) facility at SLAC. Narrow band, wide band and spectrograph measurements are used to provide a spectrally resolved yield measurement. The effects of shower development, humidity, pressure, and varying oxygen content on the yield have also been studied. Electron shower measurements are presented separately. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94025 USA. RP Reil, K (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94025 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 323 EP 326 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO92 UT WOS:000243522900082 ER PT B AU Chirkin, D Rhode, W AF Chirkin, D. Rhode, W. GP Tata Inst Fundamental Res TI All lepton propagation Monte Carlo SO Proceedings of the 29th International Cosmic Ray Conference Vol 9: HE 2 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys AB The muon propagation Monte Carlo (MMC) is a software program originally only used for muon and tau charged lepton propagation through various media or their combinations. Introduced in 2001, it is capable of propagating leptons of energies from their rest mass to 10(20)-10(30) eV. (extrapolating known cross sections to high energies). It now takes into account a multitude of effects (LPM and dielectric suppressions, decay, Moliere scattering) and implements several bremsstrahlung and photonuclear cross section parameterizations. The program has been extended to also calculate neutrino cross sections (using native CTEQ routines) and to propagate all of the neutrinos and charged leptons. All lepton particles created during the propagation are also propagated until they exit the detector or disappear. Neutrino oscillations at low energies (nu(mu) <-> nu(tau)) are considered, and tau <-> nu(tau) oscillations are simulated. Additionally, the program now includes a phenomenological atmospheric neutrino generator, which relies on fits to CORSIKA-simulated flux of atmospheric leptons. It also implements curved atmosphere (and Earth surface for detectors at depth) treatments, and accounts for muon energy losses and decay. Although the core of the program is written in Java, its distribution now includes a c/c++ interface package. The same java executable is used in AMANDA and IceCube simulation chains, and at the MMC homepage at a demonstration applet. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Chirkin, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 20 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 93 EP 96 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO94 UT WOS:000243523100024 ER PT B AU Goodman, MC AF Goodman, Maury C. CA MINOS Collaboration GP Tata Inst Fundamental Res TI Measurement of the muon charge ratio in MINOS SO Proceedings of the 29th International Cosmic Ray Conference Vol 9: HE 2 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys AB MINOS is the first large underground detector with a magnetic field. Thus it will be the first experiment to have large statistical measurement of the charge ratio relevant to high energy (TeV) muons. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Goodman, MC (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 97 EP 97 PG 1 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO94 UT WOS:000243523100025 ER PT B AU Goodman, MC AF Goodman, Maury C. CA Soudan 2 Collaboration GP Tata Inst Fundamental Res TI Atmospheric neutrinos in Soudan 2 SO Proceedings of the 29th International Cosmic Ray Conference Vol 9: HE 2 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys ID OSCILLATIONS; MACRO AB Soudan 2 has measured neutrino oscillation parameters using atmospheric vs. We have added the upward stopping mu s and downward going v induced mu s to the oscillation fits. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Goodman, MC (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 159 EP 162 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO94 UT WOS:000243523100041 ER PT B AU Goodman, MC AF Goodman, Maury C. CA MINOS Collaboration GP Tata Inst Fundamental Res TI Neutrino beam data in the MINOS (main injector neutrino oscillation search) experiment SO Proceedings of the 29th International Cosmic Ray Conference Vol 9: HE 2 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys AB A new accelerator neutrino beam (NUMI) has been built at Fermilab. This beam is directed to the 5.4 kt MINOS detector placed 735 km away in the Soudan mine in northern Minnesota. We expect to measure the atmospheric oscillation parameters (Delta m(2) and sin(2)(2 theta)) with a precision of about 10% with this experiment. The NUMI beamline started operation in January 2005. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Goodman, MC (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 311 EP 314 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO94 UT WOS:000243523100079 ER PT B AU Goodman, MC AF Goodman, Maury C. CA Double Chooz Collaboration GP Tata Inst Fundamental Res TI Calculations of muon induced backgrounds for double Chooz SO Proceedings of the 29th International Cosmic Ray Conference Vol 9: HE 2 LA English DT Proceedings Paper CT 29th International Cosmic Ray Conference CY AUG 03-10, 2005 CL Pune, INDIA SP Forsch Zentrum Karsruhe Inst Kernphys, Univ Karlsruhe, Inst Expt Kemphys, Tata Inst Fundamental Res, Int Union Pure & Appl Phys AB A new neutrino experiment is planned at the Chooz reactor in France using two detectors to measure the parameter theta(13). Two important potential backgrounds are fast neutrons from muons hitting outside the fiducial volume, and muon induced spallation of Li-9 within the fiducial volume. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Goodman, MC (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU TATA INST FUNDAMENTAL RESEARCH PI MUMBAI PA HOMI BHABHA MARG, NAVY NAGAR, COLABA, MUMBAI, MH-400005, INDIA PY 2005 BP 315 EP 318 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Physics, Particles & Fields SC Astronomy & Astrophysics; Instruments & Instrumentation; Physics GA BFO94 UT WOS:000243523100080 ER PT B AU Hickner, MA Chen, KS AF Hickner, Michael A. Chen, Ken S. BE Shah, RK Ubong, EU Samuelsen, S TI Experimental studies of liquid water droplet growth and instability at the gas diffusion layer/gas flow channel interface SO Proceedings of the 3rd International Conference on Fuel Cell Science, Engineering, and Technology LA English DT Proceedings Paper CT 3rd International Conference on Fuel Cell Science, Engineering and Technology CY MAY 23-25, 2005 CL Ypsilanti, MI SP ASME, Nanotechnol Inst, Rochester Inst Technol ID SURFACES; VISUALIZATION AB Experimental investigations were carried out to visualize the dynamic behavior (contact angle hysteresis and droplet shape) of liquid water droplets on carbon paper gas diffusion layers that are typically employed in proton exchange membrane fuel cells (PEMFCs). The experimental technique mimicks the generation of liquid water and formation of droplets in an air shear flow at the gas diffusion layer - gas flow channel interface of a simulated PEMFC cathode. Images obtained of growing liquid water droplets yield information on the contact angle hysteresis and droplet height, which were subsequently used to map droplet "instability" diagrams. These instability diagrams provide quantitative guidance on liquid water droplet removal at the gas diffusion layer/gas flow channel interface under the conditions of interest. The experimentally mapped droplet diagrams are compared with those predicted using a simplified model based on a macroscopic force balance and reasonably good agreement is obtained. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hickner, MA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-3764-5 PY 2005 BP 65 EP 69 PG 5 WC Electrochemistry; Energy & Fuels SC Electrochemistry; Energy & Fuels GA BFO19 UT WOS:000243400200010 ER PT B AU O'Brien, JE Stoots, CM Herring, JS Hartvigsen, J AF O'Brien, J. E. Stoots, C. M. Herring, J. S. Hartvigsen, J. BE Shah, RK Ubong, EU Samuelsen, S TI Hydrogen production performance of a 10-cell planar solid-oxide electrolysis stack SO Proceedings of the 3rd International Conference on Fuel Cell Science, Engineering, and Technology LA English DT Proceedings Paper CT 3rd International Conference on Fuel Cell Science, Engineering and Technology CY MAY 23-25, 2005 CL Ypsilanti, MI SP ASME, Nanotechnol Inst, Rochester Inst Technol AB An experimental study is under way to assess the performance of solid-oxide cells operating in the steam electrolysis mode for hydrogen production over a temperature range of 800 to 900 degrees C. Results presented in this paper were obtained from a ten-cell planar electrolysis stack, with an active area of 64 cm 2 per cell. The electrolysis cells are electrolyte-supported, with scandia-stabilized zirconia electrolytes (similar to 140 mu m thick), nickel-cermet steam/hydrogen electrodes, and manganite air-side electrodes. The metallic interconnect plates are fabricated from ferritic stainless steel. The experiments were performed over a range of steam inlet mole fractions (0.1 -0.6), gas flow rates (1000 - 4000 sccm), and current densities (0 to 0.38 A/cm(2)). Steam consumption rates associated with electrolysis were measured directly using inlet and outlet dewpoint instrumentation. Cell operating potentials and cell current were varied using a programmable power supply. Hydrogen production rates up to 100 Normal liters per hour were demonstrated. Values of area-specific resistance and stack internal temperatures are presented as a function of current density. Stack performance is shown to be dependent on inlet steam flow rate. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP O'Brien, JE (reprint author), Idaho Natl Lab, Idaho Falls, ID 83415 USA. NR 7 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-3764-5 PY 2005 BP 311 EP 321 PG 11 WC Electrochemistry; Energy & Fuels SC Electrochemistry; Energy & Fuels GA BFO19 UT WOS:000243400200044 ER PT B AU Hubbard, S Chen, JS Williams, K Peterson, J Rubin, Y AF Hubbard, S Chen, JS Williams, K Peterson, J Rubin, Y BE Lambot, S Gorriti, AG TI Environmental and agricultural applications of GPR SO Proceedings of the 3rd International Workshop on Advanced Ground Penetrating Radar LA English DT Proceedings Paper CT 3rd International Workshop on Advanced Ground Penetrating Radar CY MAY 02-03, 2005 CL Delft Univ Technol, Delft, NETHERLANDS SP Univ Catholique Louvain, Dept Environm Sci & Land Use Planning, Royal Mil Acad, Signal & Imaging Ctr, Ingegneria Sistemi SPA, Geophys Survey Syst, Roadscanners, 3d Radar as, European Commiss HO Delft Univ Technol DE biostimulation; characterization; environmental remediation; heterogeneity; hydraulic conductivity; monitoring; precision agriculture; water content ID BACTERIAL TRANSPORT; OYSTER; FIELD; SITE AB It is widely recognized that natural heterogeneity and the large spatial variability of hydraulic parameters control the spread of contaminants and water in the subsurface. Similarly, hydrological and biogeochemical processes are variable over a wide range of spatial scales. The inadequacy of conventional (wellbore) approaches for characterizing or monitoring the parameters and processes at over large enough areas yet with high enough resolution hinders our ability to optimally manage our natural water resources. GPR methods hold promise for improved and minimally invasive characterization and monitoring of the subsurface. This paper will review several case studies where we have successfully used GPR for a variety of environmental and precision agricultural investigations. C1 Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Hubbard, S (reprint author), Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. RI Hubbard, Susan/E-9508-2010 NR 14 TC 15 Z9 15 U1 0 U2 1 PU TU DELFT PI DELFT PA JULIANALAAN 134, DELFT, 2628 BL, NETHERLANDS BN 90-809701-1-5 PY 2005 BP 45 EP 49 DI 10.1109/AGPR.2005.1487843 PG 5 WC Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Imaging Science & Photographic Technology SC Engineering; Geology; Imaging Science & Photographic Technology GA BDF56 UT WOS:000233273500007 ER PT B AU Bollen, J Nelson, ML Araujo, R Geisler, G AF Bollen, J Nelson, ML Araujo, R Geisler, G GP ACM TI Video recommendations for the open video project SO PROCEEDINGS OF THE 5TH ACM/IEEE JOINT CONFERENCE ON DIGITAL LIBRARIES, PROCEEDINGS LA English DT Proceedings Paper CT 5th ACM/IEEE Joint Conference on Digital Libraries CY JUN 07-11, 2005 CL Denver, CO SP ACM, IEEE Comp Soc Tech Comm Pattern Analy & Mach Intelligence, ACM SIGIR, ACM SIGWEB, IEEE Tech Comm Digital Libraries DE Digital Library; recommender system; log data AB We describe a DL multimedia recommender system implemented for the Open Video project. Recommendations are generated by a spreading activation algorithm operating on a video network created from log download sequences. We compared the system's recommendations to those generated by a collaborative filtering technique. C1 Los Alamos Natl Lab, Res Lib, Los Alamos, NM USA. EM jbollen@lanl.gov; mln@cs.odu.edu; raraujo@cs.odu.edu; gary.geisler@simmons.edu NR 3 TC 1 Z9 1 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036-9998 USA BN 1-58113-876-8 PY 2005 BP 369 EP 369 DI 10.1145/1065385.1065472 PG 1 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Information Science & Library Science SC Computer Science; Information Science & Library Science GA BCO70 UT WOS:000230429800067 ER PT B AU Petrov, AY Sand, JR Zaltash, A Fischer, J Mitchell, R Wetherington, GR AF Petrov, Andrei Yu. Sand, James R. Zaltash, Abdolreza Fischer, John Mitchell, Rick Wetherington, G. Randall GP ASME TI Performance analysis of Integrated Active Desiccant Rooftop air-conditioning system operating in heating mode SO Proceedings of the ASME Advanced Energy Systems Division SE Advanced Energy Systems Division of the American Society of Mechanical Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div AB This investigation describes the performance study of a novel Integrated Active Desiccant-Vapor Compression Hybrid Rooftop (IADR) at Oak Ridge National Laboratory (ORNL) in heating mode. The tests were performed at two different ratios of outdoor/return air. Analysis of performance characteristics under each operating mode, including heating capacity and energy efficiency ratio, are given. Results of defrost cycle are also presented. Comparison between the experimental performance of IADR unit and the calculated performance of other commercially available heat pump systems at comparable operating conditions has been conducted. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Petrov, AY (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4211-8 J9 ADV ENERGY SYST DIV PY 2005 VL 45 BP 13 EP 20 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA BFM62 UT WOS:000243098600002 ER PT B AU Martinez-Frias, J Aceves, SM Flowers, DL AF Martinez-Frias, Joel Aceves, Salvador M. Flowers, Daniel L. GP ASME TI Improving ethanol life cycle energy effciency by direct combustion of wet ethanol in HCCI engines SO Proceedings of the ASME Advanced Energy Systems Division SE Advanced Energy Systems Division of the American Society of Mechanical Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div AB Homogenous Charge Compression Ignition (HCCI) is a relatively new engine technology with fundamental differences over conventional engines. HCCI engines are intrinsically fuel flexible, and can run on low grade fuels, as long as the fuel can be evaporated and heated to the point of ignition. In particular, HCCI engines can run on wet ethanol. with high concentration of water. Considering that much of the energy required for processing the ethanol is spent in distillation and dehydration, direct use of wet ethanol in an HCCI engine considerably shifts the energy balance in favor of ethanol. The results of the paper show that an HCCI engine with efficient heat recovery can operate on a 35-65% volumetric mixture of ethanol and water, while achieving a high efficiency (38.7%) and very low NOx (1.6 parts per million, clean enough to meet any existing or oncoming emissions standards). Operation of the HCCI engine with 35% ethanol by volume reduces the energy required for distillation and dehydration from 37% to 3% of the overall energy of ethanol and coproducts. The net energy gain increases considerably, from 21% to 55% of the total energy value of the fuel and coproducts. Wet ethanol combustion in HCCI engines shows great potential for improving the ethanol energy balance, and merits more detailed analysis and experimental evaluation. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Martinez-Frias, J (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave,L-644, Livermore, CA 94551 USA. RI aceves, salvador/G-9052-2011 OI aceves, salvador/0000-0001-5687-7256 NR 25 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4211-8 J9 ADV ENERGY SYST DIV PY 2005 VL 45 BP 225 EP 234 PG 10 WC Thermodynamics; Energy & Fuels; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA BFM62 UT WOS:000243098600025 ER PT B AU Jin, H Lu, WY Chames, J Yang, N AF Jin, Helena Lu, Wei-Yang Chames, Jeff Yang, Nancy GP ASME TI Characterization of LIGA microsystems using digital image correlation technique and SEM imaging SO Proceedings of the ASME Aerospace Division LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div DE digital image correlation (DIC); scanning electron microscopy (SEM); LIGA microsystems AB A new experimental technique was developed to characterize the mechanical properties of LIGA (an acronym from German words for lithography, electroplating, and molding) materials. An advanced imaging capability, scanning electron microscopy (SEM), with an integrated loading stage allows the acquisition of in situ microstructural images at the micro scale during loading. The load is measured directly from a load cell, and the displacement field is calculated from the SEM images based on the digital image correlation (DIC) technique. The DIC technique is a full-field deformation measurement technique which obtains displacement fields by comparing random speckle patterns on the specimen surface before and after deformation. The random speckle patterns are typically generated by applying a thin layer of material with high contrast to a specimen surface. Alternatively, DIC can also be applied using the microstructural features of a surface as texture patterns for correlation. DIC technique is ideally suited to characterize the deformation field of MEMS structures without the need to generate a random speckle pattern, which can be very challenging on the micro and nanoscale. In this paper, the technique is experimentally demonstrated on a LIGA specimen. The digital images showing LIGA surface features acquired during the loading can serve as random patterns for the DIC method. Therefore, full-field displacement and strain can be obtained directly on the specimen and the errors incurred by the testing system can be eliminated. C1 Sandia Natl Labs, Microsyst & Mat Mech Dept, Livermore, CA 94551 USA. RP Jin, H (reprint author), Sandia Natl Labs, Microsyst & Mat Mech Dept, Livermore, CA 94551 USA. NR 7 TC 0 Z9 0 U1 1 U2 4 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4210-X PY 2005 BP 457 EP 461 PG 5 WC Engineering, Aerospace; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BFN49 UT WOS:000243327400051 ER PT B AU Negrut, D Anitescu, M Munson, T Zapol, P AF Negrut, Dan Anitescu, Mihai Munson, Todd Zapol, Peter GP ASME TI Simulating nanoscale processes in solids using DFT and the quasicontinuum method SO PROCEEDINGS OF THE ASME APPLIED MECHANICS DIVISION SE Applied Mechanics Division of the American Society of Mechanical Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div ID MOLECULAR-DYNAMICS; ELECTRON-GAS; ENERGY AB A framework is proposed for the investigation of chemical and mechanical properties of nanostructures. The methodology is based on a two-step approach to compute the electronic density distribution in and around a nanostructure, mid then the equilibrium configuration of its nuclei. The Electronic Problem embeds interpolation and coupled cross-domain optimization techniques through a process called electronic reconstruction. In the second stage of the solution, the Ionic Problem repositions the nuclei of the nanostructure given the electronic density in the domain. The new ionic configuration is the solution of a nonlinear system based on a first-order optimality condition when minimizing the total energy associated with the nanostructure. The overall goal is a substantial increase in the dimension of the nanostructures that can be simulated by using approaches that include accurate DFT computation. This increase stems from the fact that during the solution of the Electronic Problem expensive DFT calculations are limited to a small number of subdomains. For the Ionic Problem, computational gains result from approximating the position of the nuclei in terms of a reduced number of representative nuclei following the quasicontinuum paradigm. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Negrut, D (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM negrut@mcs.anl.gov; anitescu@mcs.anl.gov; tmunson@mcs.anl.gov; zapol@mcs.anl.gov RI Zapol, Peter/G-1810-2012 OI Zapol, Peter/0000-0003-0570-9169 NR 27 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4212-6 J9 APPL MECH DIV ASME PY 2005 VL 256 BP 89 EP 101 PG 13 WC Engineering, Mechanical SC Engineering GA BFM27 UT WOS:000243037600011 ER PT B AU Jin, H Lu, WY Scheffel, S Neilsen, MK Hinnerichs, TD AF Jin, Helena Lu, Wei-Yang Scheffel, Simon Neilsen, Michael K. Hinnerichs, Terry D. GP ASME TI Characterization of mechanical behavior of polyurethane foams using digital image correlation SO Proceedings of the ASME Applied Mechanics Division SE Applied Mechanics Division of the American Society of Mechanical Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div DE foam; Digital Image Correlation (DIC); strain concentration; modeling AB Polyurethane foams have good energy absorption properties and are effective in protecting sensitive components from damages due to impact. The foam absorbs impact energy by crushing cells and undergoing large deformation. The complex deformation of the foam needs to be modeled accurately to simulate the impact events. In this paper, the Digital Image Correlation (DIC) technique was implemented to obtain the deformation field of foam specimens under compression tests. Images of foam specimen were continuously acquired using high-speed cameras. The full field displacement and strain at each incremental step of loading were calculated from these images. The closed-cell polyurethane foam used in this investigation was nominal 0.32 kg/m(boolean AND 3) (20 pcf). In the first experiment, cubic specimens were compressed uniaxially up to 60%. The full-field displacements and strains obtained using the DIC technique provide detailed information about the inhomogeneous deformation over the area of interest during loading. In the second experiment, compression tests were conducted for a simple foam structure - cubic foam specimens with a steel cylinder inclusion. The strain concentration at the interface between steel cylinder and foam was studied to simulate the deformation of foam in a typical application. In the third experiment, the foam was loaded from the steel cylinder during the compression. The strain concentration at the interface and the displacement distribution 293 over the surface were compared for cases with and without a confinement fixture to study the effects of confinement. These experimental results demonstrate that the DIC technique can be applied to polyurethane foams to study the heterogeneous deformation. The experimental data is briefly compared with the results from modeling and simulation using a viscoplastic model for the foam. C1 Sandia Natl Labs, Livermore, CA USA. RP Jin, H (reprint author), Sandia Natl Labs, MS9409, Livermore, CA USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4212-6 J9 APPL MECH DIV ASME PY 2005 VL 256 BP 293 EP 298 PG 6 WC Engineering, Mechanical SC Engineering GA BFM27 UT WOS:000243037600031 ER PT B AU Sumali, H Massad, JE Reu, PL Chaplya, PM Martin, JW AF Sumali, Hartono Massad, Jordan E. Reu, Phillip L. Chaplya, Pavel M. Martin, Jeffrey W. GP ASME TI Analytical and experimental studies of orthotropic cornersupported plates with segmented in-plane actuators SO Proceedings of the ASME Dynamic Systems and Control Division 2005, Pts A and B LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div ID CORNER-SUPPORTED PLATES; DEFLECTION MODEL AB This paper outlines a model for a corner-supported, thin, rectangular bimorph actuated by a two-dimensional array of segmented, orthotropic PVDF laminates; it investigates the realization and measurement of such a bimorph. First, a model is derived to determine the deflected shape of an orthotropic laminate for a given distribution of voltages over the actuator array. Then, boundary conditions are realized in a laboratory setup to approach the theoretical corner-supported boundary condition. Finally, deflection measurements of actuated orthotropic PVDF laminates are performed with Electronic Speckle Pattern Interferometry and are compared to the model results. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sumali, H (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4216-4 PY 2005 BP 197 EP 202 PG 6 WC Automation & Control Systems SC Automation & Control Systems GA BFY96 UT WOS:000245508100024 ER PT B AU Cooper, MA Cote, RO O'Hern, TJ Torczynski, JR Evans, LR Cross, WM AF Cooper, Marcia A. Cote, Raymond O. O'Hern, Timothy J. Torczynski, John R. Evans, Lindsey R. Cross, William M. GP ASME TI An experimental investigation of the effect of walls on gas-liquid flows through fixed particle beds SO Proceedings of the ASME Fluids Engineering Division Summer Conference - 2005, Vol 1, Pts A and B LA English DT Proceedings Paper CT ASME Fluids Engineering Division Summer Meeting CY JUN 19-23, 2005 CL Houston, TX SP ASME, Fluids Engn Div ID PACKED-BEDS; PRESSURE-DROP; PULSING FLOW; REGIME TRANSITION; DIAMETER RATIO; LAMINAR-FLOW; TRICKLE; REACTORS; HOLDUP; DOWNFLOW AB The effect of particle diameter on downward co-current gas-liquid flow through a fixed bed of particles confined within a cylindrical column is investigated. Several hydrodynamic regimes that depend strongly on the properties of the gas stream, the liquid stream, and the packed particle bed are known to exist within these systems. This experimental study focuses on characterizing the effect of wall confinement on these hydrodynamic regimes as the diameter d of the spherical particles becomes comparable to the column diameter D (or D/d becomes orderunity). The packed bed consists of polished, solid, spherical, monodisperse particles (beads) with mean diameter in the range of 0.64-2.54 cm. These diameters yield D/d values between 15 and 3.75, so this range overlaps and extends the previously investigated range for two-phase flow. Measurements of the pressure drop across the bed and across the pulses are obtained for varying gas and liquid flow rates. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cooper, MA (reprint author), Sandia Natl Labs, Albuquerque, NM 87185 USA. NR 29 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4198-7 PY 2005 BP 815 EP 823 PG 9 WC Engineering, Mechanical SC Engineering GA BFK54 UT WOS:000242485100085 ER PT B AU Guerrero, HN Eberl, KR AF Guerrero, Hector N. Eberl, Kurt R. GP ASME TI Pulse Jet Mixing of a non-Newtonian waste slurry simulant SO Proceedings of the ASME Fluids Engineering Division Summer Conference - 2005, Vol 1, Pts A and B LA English DT Proceedings Paper CT ASME Fluids Engineering Division Summer Meeting CY JUN 19-23, 2005 CL Houston, TX SP ASME, Fluids Engn Div ID YIELD STRESS AB The mixing of radioactive waste slurries by Pulse Jet Mixers (PJM) was simulated by using non-Newtonian clay suspensions. A quarter scale mockup of a 6 PJM cluster configuration was tested with different nozzle sizes of 25.4 mm, 31.8 mm, and 38.1 min I.D., nozzle velocities of 8 -18 m/sec, and yield stresses from I I to 35 Pa. Mixing was measured by dye and ultrasonic velocity probe methods. Under PJM only operation, a well mixed region or cavern is developed which is distinct from the stagnant region. The data of cavern heights to tank diameter ratio are well correlated as a function of the product of the Yield Reynolds number to the square root power and the ratio of nozzle to tank diameter. A fully mixed tank was obtained for a nozzle diameter of 38.1 mm, nozzle velocity of 18 m/sec and yield stress of 21 Pa. An alternate mixing configuration consisting of 25.4 mm nozzles and 5 spargers at 3 scfm each, 18 m/s nozzle velocity and yield stress of 30 Pa was found also to be fully mixed using glass bead tracers which also simulated large solids. C1 Savannah River Natl Lab, Aiken, SC USA. RP Guerrero, HN (reprint author), Savannah River Natl Lab, Savannah River Site, Aiken, SC USA. NR 2 TC 1 Z9 1 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4198-7 PY 2005 BP 965 EP 971 PG 7 WC Engineering, Mechanical SC Engineering GA BFK54 UT WOS:000242485100103 ER PT B AU Duignan, MR Zamecnik, JR AF Duignan, Mark R. Zamecnik, John R. GP ASME TI Cross-flow filtration performance during the washing of a simulated radioactive waste stream SO Proceedings of the ASME Fluids Engineering Division Summer Conference - 2005, Vol 1, Pts A and B LA English DT Proceedings Paper CT ASME Fluids Engineering Division Summer Meeting CY JUN 19-23, 2005 CL Houston, TX SP ASME, Fluids Engn Div DE filtration; experiment; radioactive-waste-treatment plant; slurry washing; pilot-scale AB Bechtel National, Inc. has been contracted by the Department of Energy to design a Waste Treatment and Immobilization Plant (WTP) to stabilize liquid radioactive waste that is stored at the Hanford Site as part of the River Protection Project (RPP). Because of its experience with radioactive waste stabilization, the Savannah River National Laboratory (SRNL) of the Westinghouse Savannah River Company is working with Bechtel and Washington Group International, to help design and test certain parts of the waste treatment facility. One part of the process is the separation of radioactive solids from the liquid wastes by cross-flow ultrafiltration. To test this process a cross-flow filter was used that was prototypic in porosity, length, and diameter, along with a simulated radioactive waste slurry, made to prototypically represent the chemical and physical characteristics of a Hanford waste in tank 241-AY-102/C-106. To mimic the filtration process the waste slurry undergoes several steps, including dewatering and washing. During dewatering the concentration of undissolved solids (UDS) of the simulated AY102/C106 waste is increased from 12 wt% to at least 20 wt%. Once at the higher concentration the waste must be washed to prepare for its eventual receipt in a High Level Radioactive Waste Melter to be vitrified. This paper describes the process of washing and filtering a batch of concentrated simulated waste in two cycles, which each containing 22 washing steps that used approximately 7.7 liters of a solution of 0.01 M NaOH per step. This will be the method used by the full-scale WTP to prepare the waste for vitrification. The first washing cycle started with the simulated waste that had a solids concentration of 20 wt% UDS. This cycle began with a permeate filter flux of 0.015 gpm/ft(2) (3.68 cm/hr) at 19.6 wt% UDS with a density of 1.33 kg/L, consistency of 19.1 mPa center dot s, and yield stress of 8.5 Pa. At the end of the 22 washing steps the permeate filter flux increased to 0.023 gpm/ft(2) (5.64 cm/hr) at 20.1 wt% UDS with a density of 1.17 kg/L, consistency of 12.6 mPa center dot s, and yield stress of 10.4 Pa. The average permeate filter flux during the 7 hours of Cycle 1 washing was 0.018 gpm/ft(2) (4.41 cm/hr). During Cycle 2 the simulated waste started at a permeate filter flux of 0.025 gpm/ft(2) (6.13 cm/hr). Note that the starting flux for Cycle 2 was greater than the ending flux for Cycle 1. The period between the cycles was approximately 12 hours. While no filtering occurred during that period either solids dissolution continued and/or the filter cake was dislodged somewhat with the stopping and starting of filter operation. At the end of the second set of 22 washing steps, the permeate filter flux increased to 0.032 gpm/ft(2) (7.84 cm/hr) at 20.6 wt% UDS with a density of 1.16 kg/L, consistency of 9.0 mPa center dot s, and yield stress of 8.2 Pa. The average permeate filter flux during the 4 hours of Cycle 2 washing was 029 gpm/ft(2) (7.11 cm/hr). C1 Savannah River Natl Lab, Aiken, SC 29802 USA. RP Duignan, MR (reprint author), Savannah River Natl Lab, Aiken, SC 29802 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4198-7 PY 2005 BP 995 EP 1004 PG 10 WC Engineering, Mechanical SC Engineering GA BFK54 UT WOS:000242485100106 ER PT B AU Lee, SY AF Lee, Si Y. GP ASME TI CFD modeling of solid fluidization in a column SO Proceedings of the ASME Fluids Engineering Division Summer Conference - 2005, Vol 1, Pts A and B LA English DT Proceedings Paper CT ASME Fluids Engineering Division Summer Meeting CY JUN 19-23, 2005 CL Houston, TX SP ASME, Fluids Engn Div DE fluidized column; liquid-solid granular modeling; hydraulic simulations; resin particles AB Primary objective of the work is to model the resin particles within the column during the particle fluidization and sedimentation processes and to understand hydraulic behavior for particles within column during the resin fluidization and sedimentation processes. The modeling results will assist in interpreting experimental results, providing guidance on specific details of testing design, and establishing a basic understanding of resin particle's hydraulic behavior within the column. The model was benchmarked against the literature data and the test data conducted by Savannah River National Laboratory at Savannah River Site (SRS). A scoping analysis effort has been undertaken to address the feasibility of simulating the basic fluidization and sedimentation aspects pertinent to the resin addition/removal process considered here. The existing computational fluid dynamics (CFD) code Fluent was chosen for this effort. Both fluidization and sedimentation of granular particles (i.e., of varying sizes) were based on an Eulerian model for granular flow. A two-dimensional axial symmetrical cylindrical geometry was chosen to perform the solid-fluid simulations. The column consisted of a fluid region of 48" in diameter by 94" in height where at both the top and bottom boundaries liquid fluid could pass through, but resin particle could not (i.e., assuming screens at both ends). C1 Westinghouse Savannah River Co, Savannah River Lab, Aiken, SC 29808 USA. RP Lee, SY (reprint author), Westinghouse Savannah River Co, Savannah River Lab, Aiken, SC 29808 USA. NR 6 TC 0 Z9 0 U1 1 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4198-7 PY 2005 BP 1017 EP 1023 PG 7 WC Engineering, Mechanical SC Engineering GA BFK54 UT WOS:000242485100108 ER PT B AU Bamberger, JA Greenwood, MS AF Bamberger, Judith Ann Greenwood, Margaret S. GP ASME TI Evaluation of ultrasonic methods for in-situ real-time characterization of drilling mud SO Proceedings of the ASME Fluids Engineering Division Summer Conference, Vol 2 SE FLUIDS ENGINEERING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT ASME Fluids Engineering Division Summer Meeting CY JUN 19-23, 2005 CL Houston, TX SP ASME, Fluids Engn Div ID DENSITY; SLURRY; SENSOR; LIQUID AB A real time multi-functional ultrasonic sensor system is proposed to provide automated drilling fluid monitoring that can improve the capability and development of slimhole and microhole drilling. This type of reliable, accurate, and affordable drilling fluid monitoring will reduce the overall costs in exploration and production. It will also allow more effective drilling process automation while providing rig personnel a safer and more efficient work environment. Accurate and timely measurements of drilling fluid properties such as flow rate, density, viscosity, and solid loading are key components for characterizing rate of drill penetration, providing early warning of lost circulation, and for use in real-time well control. Continuous drilling fluid monitoring enhances drilling economics by reducing the risk of costly drilling downtime, increasing production performance, and improving well control. Investigations conducted to characterize physical properties of drilling mud indicate that ultrasound can be used to provide real-time, in-situ process monitoring and control. Three types of ultrasonic measurements were evaluated which include analysis of in wall, through wall and direct contact signals. In wall measurements provide acoustic impedance (the slurry density and speed of sound product). Through wall and direct contact measurements provide speed of sound and attenuation. This information is combined to determine physical properties such as slurry density, solids concentration and can be used to detect particle size changes and the presence of low levels of gas. The measurements showed that for the frequency range investigated in-wall measurements were obtained over the slurry density range from 1500 to 2200 kg/m(3) (10 to 17 pounds solids per gallon of drilling fluid). Other measurements were obtained at densities in the 1500 to 1800 kg/m(3) range. These promising measurement results show that ultrasound can be used for real-time in-situ characterization of the drilling process by monitoring drilling mud characteristics. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bamberger, JA (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4199-5 J9 FLUID ENG D PY 2005 BP 499 EP 504 PG 6 WC Engineering, Mechanical; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BFO76 UT WOS:000243502400071 ER PT B AU Black, AR AF Black, Amalia R. GP ASME TI Numerical predictions and experimental results for a 1M diameter methane fire SO Proceedings of the ASME Heat Transfer Division 2005, Vol 1 SE Heat Transfer Division of the American Society of Mechanical Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div DE pool fires; turbulence; combustion; methane data AB Comparisons between numerical predictions and experimental data for a methane fire have been performed. Vertical velocity and turbulent kinetic energy measurements along the centerline of the fire were used to validate the models in the SIERRA/Fuego fire code. Two different turbulence treatments, a steady RANS solution with a model for buoyancy generated turbulence, and an unsteady solution with closure models based on a temporal filter width were used. Solution sensitivity to grid size has been examined for both approaches. The results indicate strong sensitivities to the turbulence model. C1 Sandia Natl Labs, Validat & Uncertainty Quantificat Proc, Albuquerque, NM 87185 USA. RP Black, AR (reprint author), Sandia Natl Labs, Validat & Uncertainty Quantificat Proc, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4221-5 J9 HEAT TRANSF DIV ASME PY 2005 VL 376-1 BP 429 EP 435 PG 7 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA BFM38 UT WOS:000243057300053 ER PT B AU O'Brien, JE Stoots, CM Hawkes, GL AF O'Brien, J. E. Stoots, C. M. Hawkes, G. L. GP ASME TI Comparison of a one-dimensional model of a high-temperature solid-oxide electrolysis stack with CFD and experimental results SO Proceedings of the ASME Heat Transfer Division 2005, Vol 2 SE Heat Transfer Division of the American Society of Mechanical Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div AB A one-dimensional model has been developed to predict the thermal and electrochemical behavior of a high-temperature steam electrolysis stack. This electrolyzer model allows for the determination of the average Nernst potential, cell operating voltage, gas outlet temperatures, and electrolyzer efficiency for any specified inlet gas flow rates, current density, cell active area, and external heat loss or gain. The model includes a temperature-dependent area-specific resistance (ASR) that accounts for the significant increase in electrolyte ionic conductivity that occurs with increasing temperature. Model predictions are shown to compare favorably with results obtained from a fully 3-D computational fluid dynamics model. The one-dimensional model was also employed to demonstrate the expected trends in electrolyzer performance over a range of operating conditions including isothermal, adiabatic, constant steam utilization, constant flow rate, and the effects of operating temperature. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP O'Brien, JE (reprint author), Idaho Natl Lab, Idaho Falls, ID 83415 USA. OI Hawkes, Grant/0000-0003-3496-8100 NR 6 TC 0 Z9 0 U1 3 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4221-5 J9 HEAT TRANSF DIV ASME PY 2005 VL 376-2 BP 117 EP 126 PG 10 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA BFM39 UT WOS:000243059900016 ER PT B AU Bernardin, JD Mudawar, I AF Bernardin, John D. Mudawar, Issam GP ASME TI Transition boiling heat transfer of droplet streams and sprays SO Proceedings of the ASME Heat Transfer Division 2005, Vol 2 SE Heat Transfer Division of the American Society of Mechanical Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div ID TRANSFER REGIMES; WATER DROPLET; SURFACE; FILM; IMPACT AB An experimental study was performed to characterize the transition boiling heat transfer rate from a surface to a stream of impinging water droplets, and to extrapolate this information to predict the transition boiling heat transfer of a dilute spray. First, transition boiling heat transfer data was gathered for a continuous stream of monodispersed water droplets striking a polished nickel surface. From this data, empirical correlations were developed to describe the heat transfer rate and heat transfer efficiency for droplet velocities between 1.0 and 7.1 in s(-1), droplet diameters ranging from 0.250 x 10(-3) to 1.002 x 10(-3) M, and surface temperatures covering 110 to 240 degrees C. By properly accounting for the hydrodynamic differences between a spray and a single droplet stream, the empirical single droplet stream heat transfer correlations were effectively extrapolated into a model for predicting the transition boiling heat flux of dilute sprays (Q" approximate to 0.5 x 10(-3) m(3)s(-1)m(-2)). C1 Los Alamos Natl Lab, Space Sci & Applicat Grp, Los Alamos, NM 87545 USA. RP Bernardin, JD (reprint author), Los Alamos Natl Lab, Space Sci & Applicat Grp, POB 1663,MS D466, Los Alamos, NM 87545 USA. NR 21 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4221-5 J9 HEAT TRANSF DIV ASME PY 2005 VL 376-2 BP 201 EP 210 PG 10 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA BFM39 UT WOS:000243059900024 ER PT B AU Min, JY Jang, SP Choi, SUS AF Min, Jung Yim Jang, Seok Pil Choi, Stephen U. S. GP ASME TI Motion of nanoparticles in nanofluids under an electric field SO Proceedings of the ASME Heat Transfer Division 2005, Vol 2 SE Heat Transfer Division of the American Society of Mechanical Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div ID THERMAL-CONDUCTIVITIES; AC ELECTROKINETICS; ENHANCEMENT AB Nanofluids - fluids with unprecedented stability of suspension nanoparticles - have attractive features such as high thermal conductivities at very low nanoparticle concentrations, strongly temperature-dependent conductivity, and three-fold higher critical heat flux compared to base fluids. These features are not explained by traditional theories of solid/liquid suspensions, such as Maxwell's theory or other macroscale approaches. Recently, Jang and Choi's model has led to the discovery, primarily by extending Einstein's theory of Brownian motion to energy transport in nanofluids, that Brownian motion of nanoparticles at the molecular and nanoscale level is a dominant mechanism governing their thermal behavior. In this paper we describe a theoretical model for controlling the motion of nanoparticles in nanofluids by means of an electric field and an analytical solution for particle motions in nanofluids. We show that the motion of nanoparticles can be controlled by use of an AC field and that the size and zeta potential of the nanoparticles are the key parameters to control nanoparticle motion beyond Brownian motion. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Min, JY (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4221-5 J9 HEAT TRANSF DIV ASME PY 2005 VL 376-2 BP 497 EP 501 PG 5 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA BFM39 UT WOS:000243059900060 ER PT B AU Turner, CJ Crawford, RH AF Turner, Cameron J. Crawford, Richard H. GP ASME TI Selecting an appropriate metamodel: The case for NURBs metamodels SO Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, 2005, Vol 2, Pts A and B LA English DT Proceedings Paper CT ASME International Design Engineering Technical Conference/Computers and Information in Engineering Conference CY SEP 24-28, 2006 CL Long Beach, CA SP ASME, Design Engn Div, ASME, Comp & Informat Engn Div ID ADAPTIVE REGRESSION SPLINES AB Metamodels are becoming increasingly popular for representing unknown black box functions. Several metamodel classes exist, including response surfaces and spline-based models, kriging and radial basis function models, and neural networks. For an inexperienced user, selecting an appropriate metamodel is difficult due to a limited understanding of the advantages and disadvantages of each metamodel type. This paper reviews several major metamodeling techniques with respect to their advantages and disadvantages and compares several significant metamodel types for use as a black box metamodeling tool. The results make a strong case for using Non-Uniform Rational B-spline (NURBs) HyPerModels as a generic metamodeling tool. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Turner, CJ (reprint author), Los Alamos Natl Lab, POB 1663,MS J580, Los Alamos, NM 87545 USA. RI Turner, Cameron/N-7266-2014 OI Turner, Cameron/0000-0001-9546-2328 NR 31 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4739-X PY 2005 BP 759 EP 770 PG 12 WC Computer Science, Artificial Intelligence; Engineering, Manufacturing; Engineering, Mechanical SC Computer Science; Engineering GA BFI44 UT WOS:000242014000077 ER PT B AU Turner, CJ Crawford, RH AF Turner, Cameron J. Crawford, Richard H. GP ASME TI Adapting non-uniform rational B-spline fitting approaches to metamodeling SO Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference 2005, Vol 3, Pts A and B LA English DT Proceedings Paper CT ASME International Design Engineering Technical Conference/Computers and Information in Engineering Conference CY SEP 24-28, 2006 CL Long Beach, CA SP ASME, Design Engn Div, ASME, Comp & Informat Engn Div AB Modern engineering design requires the exploration of complex nonlinear design spaces that relate large numbers of design variables and performance criteria. Effective exploration and decision making requires the availability of efficient representations of high dimensional design spaces. Techniques from the field of metamodeling, which builds models of models, are often used to represent complex design relationships. We have developed an alternative, spline-based metamodeling technique that is amenable to adaptive representation of high dimensional spaces and facilitates optimization-based exploration of such spaces. This paper describes our technique for fitting Non-Uniform Rational B-splines (NURBs) to points in a design space generated from simulations or experiments. The algorithm is illustrated with examples from metamodeling and nonlinear optimization literature. The results indicate that our method achieves an average global correlation of more than 99% and an average maximum local RMS error of less than 3% of full scale. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Turner, CJ (reprint author), Los Alamos Natl Lab, POB 1663,MS J580, Los Alamos, NM 87545 USA. RI Turner, Cameron/N-7266-2014 OI Turner, Cameron/0000-0001-9546-2328 NR 27 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4740-3 PY 2005 BP 165 EP 177 PG 13 WC Computer Science, Interdisciplinary Applications; Engineering, Multidisciplinary SC Computer Science; Engineering GA BFI27 UT WOS:000241986000020 ER PT B AU Negrut, D Rampalli, R Ottarsson, G Sajdak, A AF Negrut, Dan Rampalli, Rajiv Ottarsson, Gisli Sajdak, Anthony GP ASME TI On the use of the HHT method in the context of index 3 differential algebraic equations of multibody dynamics SO PROCEEDINGS OF THE ASME INTERNATIONAL DESIGN ENGINEERING TECHNICAL CONFERENCES AND COMPUTERS AND INFORMATION IN ENGINEERING CONFERENCE, VOL 6, PTS A-C LA English DT Proceedings Paper CT 5th International Conference on Multibody Systems, Nonlinear Dynamics, and Control CY SEP 24-28, 2005 CL Long Beach, CA SP ASME, Design Engn Div, ASME, Comp & Informat Engn Div ID IMPROVED NUMERICAL DISSIPATION; STRUCTURAL DYNAMICS; TIME INTEGRATION; MECHANICAL SYSTEMS AB The paper presents theoretical and implementation aspects related to a new numerical integrator available in the 2005 version of the MSC.ADAMS/Solver C++. The starting point for the new integrator is the Hilber-Hughes-Taylor method (HHT also known as a-method) that has been widely used in the finite element community for more than two decades. The method implemented is tailored to answer the challenges posed by the numerical solution of index 3 Differential Algebraic Equations that govern the time evolution of a multi-body system. The proposed integrator was tested with more than 1,600 models prior to its release in the 2005 version of the simulation package MSC.ADAMS. In this paper an all-terrain-vehicle model with flexible chassis is used to prove the good efficiency and accuracy of the method. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Negrut, D (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM negrut@mcs.anl.gov; rajiv.rampalli@mscsoftware.com; gisli.ottarsson@mscsoftware.com; anthony.sajdak@mscsoftware.com NR 30 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4743-8 PY 2005 BP 207 EP 218 PG 12 WC Engineering, Multidisciplinary; Engineering, Mechanical; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA BFJ36 UT WOS:000242326200020 ER PT B AU Serban, R Hindmash, AC AF Serban, Radu Hindmash, Alan C. GP ASME TI CVODES, the sensitivity-enabled ODE solver in SUNDIALS SO Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Vol 6, Pts A-C LA English DT Proceedings Paper CT 5th International Conference on Multibody Systems, Nonlinear Dynamics, and Control CY SEP 24-28, 2005 CL Long Beach, CA SP ASME Design Engn Div, ASME Comp & Informat Engn Div ID DIFFERENTIAL-ALGEBRAIC SYSTEMS; EQUATIONS; SOFTWARE AB CVODES, which is part of the SUNDIALS software suite, is a stiff and nonstiff ordinary differential equation initial value problem solver with sensitivity analysis capabilities. CVODES is written in a data-independent manner, with a highly modular structure to allow incorporation of different preconditioning and/or linear solver methods. It shares with the other SUNDIALS solvers several common modules, most notably the generic kernel of vector operations and a set of generic linear solvers and preconditioners. CVODES solves the IVP by one of two methods - backward differentiation formula or Adams-Moulton - both implemented in a variable-step, variable-order form. The forward sensitivity module in CVODES implements the simultaneous corrector method, as well as two avors of staggered corrector methods. Its adjoint sensitivity module provides a combination of check-pointing and cubic Hermite interpolation for the ef cient pound generation of the forward solution during the adjoint system integration. We describe the current capabilities of CVODES, its design principles, and its user interface, and provide an example problem to illustrate the performance of CVODES. C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Serban, R (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 808,L-560, Livermore, CA 94551 USA. NR 23 TC 3 Z9 3 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4743-8 PY 2005 BP 257 EP 269 PG 13 WC Engineering, Multidisciplinary; Engineering, Mechanical; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA BFJ36 UT WOS:000242326200025 ER PT B AU Griffith, DT Turner, JD Junkins, JL AF Griffith, D. Todd Turner, James D. Junkins, John L. GP ASME TI Some applications of automatic differentiation to rigid, flexible, and constrained multibody dynamics SO Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Vol 6, Pts A-C LA English DT Proceedings Paper CT 5th International Conference on Multibody Systems, Nonlinear Dynamics, and Control CY SEP 24-28, 2005 CL Long Beach, CA SP ASME Design Engn Div, ASME Comp & Informat Engn Div AB In this paper, we discuss several applications of automatic differentiation to multibody dynamics. The scope of this paper covers the rigid, flexible, and constrained dynamical systems. Particular emphasis is placed on the development of methods for automating the generation of equations of motion and the simulation of response using automatic differentiation. We also present a new approach for generating exact dynamical representations of flexible multibody systems in a numerical sense using automatic differentiation. Numerical results will be presented to detail the efficiency of the proposed methods. C1 Sandia Natl Labs, Struct Dynam Res Dept, Albuquerque, NM 87185 USA. RP Griffith, DT (reprint author), Sandia Natl Labs, Struct Dynam Res Dept, POB 5800, Albuquerque, NM 87185 USA. RI Griffith, Daniel/C-2807-2014 OI Griffith, Daniel/0000-0002-7767-3700 NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4743-8 PY 2005 BP 271 EP 281 PG 11 WC Engineering, Multidisciplinary; Engineering, Mechanical; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA BFJ36 UT WOS:000242326200026 ER PT B AU Foster, JT Barhorst, AA Wong, CNS Bement, MT AF Foster, J. T., Jr. Barhorst, A. A. Wong, C. N. (Simon Bement, M. T. GP ASME TI Modeling and experimental verification of frictional contact impact in loose bolted joint elastic structures SO Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Vol 6, Pts A-C LA English DT Proceedings Paper CT 5th International Conference on Multibody Systems, Nonlinear Dynamics, and Control CY SEP 24-28, 2005 CL Long Beach, CA SP ASME Design Engn Div, ASME Comp & Informat Engn Div ID CONSTRAINT ADDITION DELETION; FLEXIBLE MULTIBODY SYSTEMS; BODY MECHANICAL SYSTEMS; COULOMB-FRICTION; DYNAMICS; SIMULATION; STICTION AB In this paper a dry frictional contact-impact model of two elastic beams joined by a loose bolted joint is developed and compared to experimental data. The model utilizes the concept of instantly applied non-holonomic constraints and pseudo-speeds to provide the variable structure hybrid parameter dynamical equations for the system. Simulation logic is developed and presented in outline form. An experimental apparatus is described. Simulation results and experimental results are compared and discussed. C1 Penetrator Technol, Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Barhorst, AA (reprint author), Penetrator Technol, Sandia Natl Labs, Albuquerque, NM 87123 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4743-8 PY 2005 BP 515 EP 531 PG 17 WC Engineering, Multidisciplinary; Engineering, Mechanical; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA BFJ36 UT WOS:000242326200050 ER PT B AU Weir, NA Cipra, RJ AF Weir, Nathan A. Cipra, Raymond J. GP ASME TI Modeling and analysis of a vibratory micro-pin feeder using impulse-based simulation SO PROCEEDINGS OF THE ASME INTERNATIONAL DESIGN ENGINEERING TECHNICAL CONFERENCES AND COMPUTERS AND INFORMATION IN ENGINEERING CONFERENCE, VOL 6, PTS A-C LA English DT Proceedings Paper CT 5th International Conference on Multibody Systems, Nonlinear Dynamics, and Control CY SEP 24-28, 2005 CL Long Beach, CA SP ASME, Design Engn Div, ASME, Comp & Informat Engn Div DE microassembly; micromanipulation; vibratory feeder; microparts feeding; microparts singulation; LIGA; MEMS; impulse-based simulation ID BODIES INCLUDING FRICTION; DYNAMICS; IMPACT AB A variety of methods exist for the assembly of microscale devices. One such strategy uses microscale force-fit pin insertion to assemble LIGA parts together. One of the challenges associated with this strategy is the handling of small pins which are 170 microns in diameter and with lengths ranging from 500 to 1000 microns. In preparation for insertion, a vibratory micro-pin feeder has been used to successfully singulate and manipulate the pins into a pin storage magazine. This paper presents the development of a deterministic model, simulation tool, and methodology in order to identify and analyze key performance attributes of the vibratory micro-pin feeder system. A brief parametric study was conducted to identify the effects of changing certain system parameters on the bulk behavior of the system, namely the capture rate of the pins. Results showing trends have been obtained for a few specific cases. These results indicate that different system parameters can be chosen to yield better system performance. C1 Sandia Natl Labs, Intelligent Syst & Robot Ctr, Albuquerque, NM 87185 USA. RP Weir, NA (reprint author), Sandia Natl Labs, Intelligent Syst & Robot Ctr, POB 5800,MS 1007, Albuquerque, NM 87185 USA. EM naweir@sandia.gov; cipra@purdue.edu NR 33 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4743-8 PY 2005 BP 533 EP 543 PG 11 WC Engineering, Multidisciplinary; Engineering, Mechanical; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA BFJ36 UT WOS:000242326200051 ER PT B AU Brooks, SH Magleby, SP Howell, LL AF Brooks, Scott H. Magleby, Spencer P. Howell, Larry L. GP ASME TI Grasping mechanisms with self-centering and force-balancing characteristics SO Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Vol 7, Pts A and B LA English DT Proceedings Paper CT 29th Mechanisms and Robotics Conference CY SEP 24-28, 2005 CL Long Beach, CA SP ASME Design Engn Div, ASME Comp & Informat Engn Div ID LENSES AB This paper presents grasping mechanism configurations that are self-centering with balanced reaction forces, and develops the design principles, models, and analysis methods of achieving these characteristics in compliant mechanisms. The configurations emulate the self-centering and balanced actuation force characteristics exhibited by hydraulic disc-brake systems. Purely mechanical grasping systems, in which both the mechanism and the object being grasped are rigidly attached to ground, require 2 degrees of freedom in the grasping mechanism. It is shown that compliant configurations can exhibit the balanced-force behavior as well as figid-link mechanisms. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Brooks, SH (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4744-6 PY 2005 BP 405 EP 414 PG 10 WC Robotics SC Robotics GA BFJ38 UT WOS:000242330500045 ER PT B AU Wilcox, DL Howell, LL AF Wilcox, Daniel L. Howell, Larry L. GP ASME TI Double-tensural bistable mechanisms (DTBM) with on-chip actuation and spring-like post-bistable behavior SO Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Vol 7, Pts A and B LA English DT Proceedings Paper CT 29th Mechanisms and Robotics Conference CY SEP 24-28, 2005 CL Long Beach, CA SP ASME Design Engn Div, ASME Comp & Informat Engn Div DE bistable mechanisms; compliant mechanisms; thermal on-chip actuation; microelectromechanical systems; MEMS ID BEAM; CONFIGURATIONS; INPLANE; DESIGN AB A set of mechanisms called Double Tensural Bistable Mechanisms (DTBM) is presented. DTBMs are fully compliant linear bistable mechanisms that have two bending segments that undergo tension loading. Five configurations of the DTBM are designed, fabricated using surface micromachining, and tested. Measured force and displacement are compared with finite element analysis (FEA) predictions. For two DTBM configurations, a novel post-switch, large-displacement, low-k linear spring behavior is predicted by the FEA models and verified through experimental testing. On-chip actuation of two devices is achieved using thermomechanical in-plane microactuators; (TIMs). The DTBM mechanism set explores a relatively new design space for fully compliant micromechanisms, and mechanisms from this class have promise in such applications as shutter positioning, microvalves, electrical relays, inertial sensors and g/time switches. C1 Sandia Natl Labs, Albuquerque, NM 87111 USA. RP Howell, LL (reprint author), Sandia Natl Labs, 4608 Athens Dr NE, Albuquerque, NM 87111 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4744-6 PY 2005 BP 537 EP 546 PG 10 WC Robotics SC Robotics GA BFJ38 UT WOS:000242330500060 ER PT B AU Harden, T Kapoor, C Tesar, D AF Harden, Troy Kapoor, Chelan Tesar, Delbert GP ASME TI Obstacle avoidance influence coefficients for manipulator motion planning SO PROCEEDINGS OF THE ASME INTERNATIONAL DESIGN ENGINEERING TECHNICAL CONFERENCES AND COMPUTERS AND INFORMATION IN ENGINEERING CONFERENCE, VOL 7, PTS A AND B LA English DT Proceedings Paper CT 29th Mechanisms and Robotics Conference CY SEP 24-28, 2005 CL Long Beach, CA SP ASME Design Engn Div, ASME Comp & Informat Engn Div ID REDUNDANT MANIPULATORS; DISTANCE AB Motion planning in cluttered environments is a weakness of current robotic technology. While research addressing this issue has been conducted, few efforts have attempted to use minimum distance rates of change in motion planning. Geometric influence coefficients provide extraordinary insight into the interactions between a robot and its environment. They isolate the geometry of distance functions from system inputs and make the higher-order properties of minimum distance magnitudes directly available. Knowledge of the higher order properties of minimum distance magnitudes can be used to predict the future obstacle avoidance, path planning, and/or target acquisition state of a manipulator system and aid in making intelligent motion planning decisions. Here, first and second order geometric influence coefficients for minimum distance magnitudes are rigorously developed for several simple modeling primitives. A general method for similar derivations using new primitives and an evaluation of finite difference approximations versus analytical second order coefficient calculations are presented. Two application examples demonstrate the utility of minimum distance magnitude influence coefficients in motion planning. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Harden, T (reprint author), Los Alamos Natl Lab, POB 1663,MS J580, Los Alamos, NM 87545 USA. EM harden@lanl.gov; chetan@mail.utexas.edu; tesar@mail.utexas.edu NR 40 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4744-6 PY 2005 BP 735 EP 747 PG 13 WC Robotics SC Robotics GA BFJ38 UT WOS:000242330500084 ER PT B AU Schraad, MW AF Schraad, Mark W. GP ASME TI A stochastic constitutive model and multi-field approach for modeling the dynamic response of cellular materials SO Proceedings of the ASME Materials Division SE Materials Division of the American Society of Mechanial Engineers LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 05-11, 2005 CL Orlando, FL SP ASME, Proc Ind Div, ASME, Rail Transportat Div, ASME, Noise Control & Acoust Div, ASME, Triol Div, ASME, Pressure Vessels & Piping Div, ASME, Bioengn Div, ASME, Mat Div, ASME, Appl Mech Div, ASME, Fluids Engn Div, ASME, Micro Elect Mech Syst Div, ASME, Heat Transfer Div, ASME, Nucl Engn Div, ASME, Power Div, ASME, Solar Energy Div, ASME, Safety Engn & Risk Anal Div, ASME, Technol & Soc Div, ASME, Adv Energy Syst Div, ASME, Aerosp Div, ASME, Comp & Informat Engn Div AB A multi-field approach is developed for simulating the dynamic response of cellular materials. A stochastic constitutive model is incorporated for representing the stress-strain behavior of cellular solids, however a description of the coupled response of the permeating fluids also is included. This new approach is used to study the influence of various permeating fluids and the effects of aperture size and loading rate on the continuum-scale response of such systems. Results demonstrate that the permeating fluid can play a significant role in the response of cellular materials, contributing to the load-carrying capacity and affecting rate dependence and signal propagation speeds. Furthermore, the results point to the usefulness of the multi-field formulation and provide evidence to suggest that any modeling approach developed for cellular materials provide a proper accounting of the pressure evolution and flow behavior of the fluids present in these material systems. C1 Los Alamos Natl Lab, Div Theoret, Fluid Dynam Grp, Los Alamos, NM 87545 USA. RP Schraad, MW (reprint author), Los Alamos Natl Lab, Div Theoret, Fluid Dynam Grp, POB 1663, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4234-7 J9 MATER DIV ASME PY 2005 VL 100 BP 525 EP 534 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA BFM25 UT WOS:000243036600069 ER PT B AU Biruduganti, MS Gupta, SB McConnell, S Sekar, R AF Biruduganti, Munidhar S. Gupta, Sreenath B. McConnell, Steven Sekar, Raj GP ASME TI Performance of a natural gas engine using variable air composition SO Proceedings of the ASME Power Conference 2005, Pts A and B LA English DT Proceedings Paper CT ASME Power Conference 2005 CY APR 05-07, 2005 CL Chicago, IL SP ASME AB A comparative analysis of nitrogen and oxygen enriched combustion is presented in this paper. Nitrogen enrichment of intake air is proposed as an alternative to Exhaust Gas Recirculation (EGR). NOx reduction by EGR is not very promising due to engine reliability concerns and increased maintenance costs. Air separation membrane, on the other hand, is a potential strategy for NOx reduction due to uncompromised reliability of engine performance. Oxygen-rich and nitrogen-rich streams are produced by passing air through a nonporous polymeric membrane. Nitrogen Enriched Air (NEA) reduces NO, formation by lowering in-cylinder combustion temperatures but with a compromise in Fuel Conversion Efficiency (FCE). However, advanced ignition timing improves FCE considerably. Oxygen Enriched Air (OEA), on the other hand, improves FCE due to the availability of extra oxygen for better combustion which results in 'higher bulk gas temperatures and NOx emissions. This behavior could be controlled by retarding the ignition timing. Experimental results of nitrogen and oxygen enriched combustion of a Kohler M12 generator (converted to operate with natural gas) is presented in this paper. A 68% reduction in NO, and a 0.8% drop in FCE were observed at -30 ATDC ignition timing (IT) with 2.1% N-2 enrichment (40 slpm). A 9% O-2 enrichment (40 slpm) at -30 ATDC IT improved FCE by 1% but with higher NO, emissions. The increase in NOx emissions was minimal with a 2% improvement in FCE at -10 ATDC IT and 9% O-2 enrichment (40 slpm). Some of the drawbacks encountered were engine misfire at higher concentrations of nitrogen enriched air and retarded ignition timing resulting in poor FCE. This paper discusses both the approaches and highlights the benefits of nitrogen enrichment using an air separation membrane over its counterpart for NOx reduction. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Biruduganti, MS (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4182-0 PY 2005 BP 743 EP 749 PG 7 WC Thermodynamics; Energy & Fuels; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA BFI46 UT WOS:000242015800101 ER PT B AU Tucker, D Lawson, L Gemmen, R AF Tucker, David Lawson, Larry Gemmen, Randall GP ASME TI Characterization of air flow management and control in a fuel cell turbine hybrid power system using hardware simulation SO Proceedings of the ASME Power Conference 2005, Pts A and B LA English DT Proceedings Paper CT ASME Power Conference 2005 CY APR 05-07, 2005 CL Chicago, IL SP ASME AB Air flow management and control in a fuel cell gas turbine hybrid power system is evaluated using the Hybrid Performance (Hyper) hardware simulation facility at the National Energy Technology Laboratory (NETL), U.S. Department of Energy. The Hyper facility at NETL is a hardware simulation of a fuel cell gas turbine hybrid power system capable of emulating systems in the range of 300kW to 900kW. The hardware portion is comprised of a modified single-shaft gas turbine, a high performance exhaust gas recuperator, several pressure vessels that represent the volumes and flow impedances of the fuel cell and combustors, and the associated integration piping. The simulation portion consists of a real time fuel cell model that is used to control a natural gas burner which replicates the thermal output of a solid oxide fuel cell. Thermal management in the fuel cell component of the hybrid system, especially during an imposed load transient, is improved through the control of cathode air flow. This can be accomplished in a fuel cell turbine hybrid by diverting air around the fuel cell system. Two methods for air flow control are presented in the paper. In this paper, the use of bleed air by-pass and cold air by-pass are characterized quantitatively in terms of compressor inlet flow, process limits, system efficiency and system performance. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP Tucker, D (reprint author), US DOE, Natl Energy Technol Lab, 3610 Collins Ferry Rd, Morgantown, WV 26507 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4182-0 PY 2005 BP 959 EP 967 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA BFI46 UT WOS:000242015800131 ER PT B AU Gosselin, SR Simonen, FA Carter, RG Davis, JM Stevens, GL AF Gosselin, S. R. Simonen, F. A. Carter, R. G. Davis, J. M. Stevens, G. L. GP ASME TI Enhanced asivie section XI Appendix L flaw tolerance procedure SO Proceedings of the ASME Pressure Vessels and Piping Conference - 2005, Vol 1 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code has worked since the early 1990s to develop guidelines for the nuclear power industry to evaluate the serviceability of components that are adversely subjected to fatigue stresses. Results of this work formed the basis for a non-mandatory Appendix L that became part of the 1996 Addenda to the 1995 Edition of Section XI [I]. A key part of this appendix was the introduction of a damage tolerance based examination strategy designed to assure that the component will operate reliability between subsequent inspections. Since the issuance of Appendix L, new data on the flaw detection capabilities have become available, and these data show that ultrasonic inspections can detect flaws much smaller than assumed during the original development of Appendix L. This information allows for significantly smaller sizes for initial postulated flaws. Additionally, Appendix L did not address the potential for multiple fatigue crack initiation sites for a given location on the component In 1999 the ASME Working Group on Operating Plant Criteria (WGOPC) re-established the Task Group on Operating Plant Fatigue Assessments (TGOPFA) to address these concerns. This paper summarizes the research results, supporting computations, and technical bases for TGOPFA recommended Appendix L improvements. A detailed sample calculation is presented for a PWR charging nozzle-to-pipe weld. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gosselin, SR (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4186-3 J9 PRES VES P PY 2005 BP 5 EP 16 PG 12 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO08 UT WOS:000243383200002 ER PT B AU Chopra, OK Alexandreanu, B Shack, WJ AF Chopra, Omesh K. Alexandreanu, Bogdan Shack, William J. GP ASME TI Crack growth rates of alloy 600 from the Davis-Besse reactor CRDM nozzle #3 in PWR environment SO Proceedings of the ASME Pressure Vessels and Piping Conference - 2005, Vol 1 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB Reactor-vessel internal components made of nickel-base alloys are susceptible to environmentally assisted cracking. A better understanding of the causes and mechanisms of this cracking may permit less conservative estimates of damage accumulation and requirements on inspection intervals of pressurized water reactors (PWRs). This paper presents crack growth rate (CGR) results for Alloy 600 removed from nozzle #3 of the Davis-Besse (D-B) control rod drive mechanism (CRDM). The tests were conducted on (1/)(4)-T or (1)(/2)-T compact tension specimens in simulated PWR environment, and crack extensions were determined by DC potential drop measurements. The experimental CGRs under cyclic and constant load are compared with the existing CGR data for Alloy 600 to determine the relative susceptibility of the D-B CRDM nozzle alloy to environmentally enhanced cracking. The CGRs under constant load for the nozzle material are higher than those predicted by the best-fit curve for Alloy 600 at 316 degrees C. The results also indicate significant enhancement of CGRs under cyclic loading in the PWR environment. Characterization of the material microstructure and tensile properties is described. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Chopra, OK (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 29 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4186-3 J9 PRES VES P PY 2005 BP 171 EP 180 PG 10 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO08 UT WOS:000243383200018 ER PT B AU Alexandreanu, B Chopra, O Shack, WJ AF Alexandreanu, Bogdan Chopra, Omesh Shack, Willaim J. GP ASME TI Crack growth rates of A182 and A82 alloys from the VC Summer reactor vessel nozzle-to-pipe weld SO Proceedings of the ASME Pressure Vessels and Piping Conference - 2005, Vol 1 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Alexandreanu, B (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4186-3 J9 PRES VES P PY 2005 BP 181 EP 181 PG 1 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO08 UT WOS:000243383200019 ER PT B AU Dickson, TL EricksonKirk, MT AF Dickson, T. L. EricksonKirk, M. T. GP ASME TI An overview of the pressurized thermal shock Re-evaluation Project SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 3 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB In 1999, a study sponsored by the United States Nuclear Regulatory Commission (NRC) suggested that advances in the technologies associated with the physics of pressurized-thermal-shock (PTS) events developed since the derivation of the PTS regulations (established in the early-mid eighties) had the potential to establish a technical basis that could justify a relaxation in the current PTS-related regulations. A relaxation of these regulations could have profound implications for plant license extension considerations. Subsequently, the NRC initiated the interdisciplinary PTS Re-evaluation Project. During the five year project, an updated comprehensive computational methodology evolved, within the framework established by modem probabilistic risk assessment (PRA) techniques, through interactions among experts in relevant disciplines from the NRC staff, their contractors, and representatives from the nuclear industry. During 2004, the updated computational methodology was applied to three domestic commercial pressurized water reactors (PWRs). The most recent results of the PTS Re-evaluation Project provide a technical basis to support a relaxation of the current PTS regulations while continuing to provide reasonable assurance of adequate protection to public health and safety. The details of the updated computational methodology, the mathematical models, the analysis results, key findings, and supporting information have recently been drafted in several very detailed and lengthy formal reports. These reports are currently under review at the NRC. An objective of this paper is to provide a short overview of the improved computational methodology, analysis results, and key findings of the PTS reevaluation project. To demonstrate that a technical basis has been established to support a relaxation of the current PTS regulations, it is helpful to understand the derivation of the current PTS regulations; therefore, another objective of this paper is to contrast the interpretation of the analysis results of the PTS re-evaluation to those performed in the eighties from which the current PTS regulations were derived. C1 Oak Ridge Natl Lab, Computat Sci & Engn Div, Oak Ridge, TN 37831 USA. RP Dickson, TL (reprint author), Oak Ridge Natl Lab, Computat Sci & Engn Div, POB 2008, Oak Ridge, TN 37831 USA. NR 35 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4188-X J9 PRES VES P PY 2005 VL 3 BP 347 EP 358 PG 12 WC Engineering, Mechanical SC Engineering GA BFO18 UT WOS:000243400000044 ER PT B AU Bishop, JE Voth, TE Brown, KH AF Bishop, Joseph E. Voth, Thomas E. Brown, Kevin H. GP ASME TI Semi-infinite target penetration by ogive-nose penetrators: ALEGRA/SHISM code predictions for ideal and non-ideal impacts SO PROCEEDINGS OF THE ASME PRESSURE VESSELS AND PIPING CONFERENCE 2005, VOL 4 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE oblique impact; angle of attack; penetration; ALE; SHISM; ALEGRA ID 6061-T6511 ALUMINUM TARGETS; BALLISTIC PENETRATION; STEEL PROJECTILES; SIMULATIONS AB The physics of ballistic penetration mechanics is of great interest in penetrator and counter-measure design. The phenomenology associated with these events can be quite complex and a significant number of studies have been conducted ranging from purely experimental to 'engineering' models based on empirical and/or analytical descriptions to fully-coupled penetrator/target, thermo-mechanical numerical simulations. Until recently, however, there appears to be a paucity of numerical studies considering 'non-ideal' impacts [1]. The goal of this work is to demonstrate the SHISM algorithm implemented in the ALEGRA Multi-Material ALE (Arbitrary Lagrangian Eulerian) code [13]. The SHISM algorithm models the three-dimensional continuum solid mechanics response of the target and penetrator in a fully coupled manner. This capability allows for the study of 'non-ideal' impacts (e.g. pitch, yaw and/or obliquity of the target/penetrator pair). In this work predictions using the SHISM algorithm are compared to previously published experimental results for selected ideal and non-ideal impacts of metal penetrator-target pairs. These results show good agreement between predicted and measured maximum depth-of-penetration, DOP, for ogive-nose penetrators with striking velocities in the 0.5 to 1.5 km/s range. Ideal impact simulations demonstrate convergence in predicted DOP for the velocity range considered. A theory is advanced to explain disagreement between predicted and measured DOP at higher striking velocities. This theory postulates uncertainties in angle-of-attack for the observed discrepancies. It is noted that material models and associated parameters used here, were unmodified from those in the literature. Hence, no tuning of models was performed to match experimental data. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Bishop, JE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 28 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4189-8 J9 PRES VES P PY 2005 VL 4 BP 733 EP 742 PG 10 WC Engineering, Mechanical SC Engineering GA BFO20 UT WOS:000243400300086 ER PT B AU Berg, VS Preece, DS Stofleth, JH Risenmay, MA AF Berg, Vanessa S. Preece, Dale S. Stofleth, Jerome H. Risenmay, Mathew A. GP ASME TI Kevlar and carbon composite body armor - Analysis and testing SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 4 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB Kevlar materials make excellent body armor due to their fabric-like flexibility and ultra-high tensile strength. Carbon composites are made up from many layers of carbon AS-4 material impregnated with epoxy. Fiber orientation is bidirectional, orientated at 0 degrees and 90 degrees. They also have ultra-high tensile strength but can be made into relatively hard armor pieces. Once many layers are cut and assembled they can be ergonomicically shaped in a mold during the heated curing process. Kevlar and carbon composites can be used together to produce light and effective body armor. This paper will focus on computer analysis and laboratory testing of a Kevlar/carbon composite cross-section proposed for body armor development. The carbon composite is inserted between layers of Kevlar. The computer analysis was performed with a Lagrangian transversely isotropic material model for both the Kevlar and Carbon Composite. The computer code employed is AUTODYN. Both the computer analysis and laboratory testing utilized different fragments sizes of hardened steel impacting on the armor cross-section. The steel fragments are right-circular cylinders. Laboratory testing was undertaken by firing various sizes of hardened steel fragments at square test coupons of Kevlar layers and heat cured carbon composites. The V-50 velocity for the various fragment sizes was determined from the testing. This V-50 data can be used to compare the body armor design with other previously designed armor systems. AUTODYN [1] computer simulations of the fragment impacts were compared to the experimental results and used to evaluate and guide the overall design process. This paper will include the detailed transversely isotropic computer simulations of the Kevlar/carbon composite cross-section as well as the experimental results and a comparison between the two. Conclusions will be drawn about the design process and the validity of current computer modeling methods for Kevlar and carbon composites. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Berg, VS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 1 Z9 1 U1 3 U2 12 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4189-8 J9 PRES VES P PY 2005 VL 4 BP 787 EP 795 PG 9 WC Engineering, Mechanical SC Engineering GA BFO20 UT WOS:000243400300092 ER PT B AU Howard, B Gelder, L AF Howard, Boyd Gelder, Larry GP ASME TI Digital radiography of general purpose fissile packages SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 5 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers C1 WSRC Savannah River Natl Lab, Savannah, GA USA. RP Howard, B (reprint author), WSRC Savannah River Natl Lab, Savannah, GA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4190-1 J9 PRES VES P PY 2005 VL 5 BP 121 EP 121 PG 1 WC Engineering, Mechanical; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BFO11 UT WOS:000243398000017 ER PT B AU Lam, PS Wang, JJA Scarth, D Cipolla, R Rodgers, D AF Lam, Poh-Sang Wang, John Jy-An Scarth, Douglas Cipolla, Russell Rodgers, Douglas GP ASME TI Applications of fracture mechanics in failure assessment - Introduction SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers C1 Savannah River Natl Lab, Aiken, SC USA. RP Lam, PS (reprint author), Savannah River Natl Lab, Aiken, SC USA. OI Wang, Jy-An/0000-0003-2402-3832 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 49 EP 51 PG 3 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900007 ER PT B AU Gosselin, SR Simonen, FA Heasler, PG Becker, FL Doctor, SR Carter, RG AF Gosselin, S. R. Simonen, F. A. Heasler, P. G. Becker, F. L. Doctor, S. R. Carter, R. G. GP ASME TI Performance demonstration based probability of detection (POD) curves for fatigue cracks in piping SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB This paper evaluates non-destructive examination (NDE) detection capabilities for fatigue cracks in piping. Industry performance demonstration initiative (PDI) data for fatigue crack detection were used to develop a matrix of statistically based probability of detection (POD) curves that consider various NDE performance factors. Seven primary performance factors were identified - Material, Crack Geometry/Type, NDE Examination Access, NDE Procedure, Examiner Qualification, Pipe Diameter, and Pipe Wall Thickness. A database of 16,181 NDE performance observations, with 18 fields associated with each observation, was created and used to develop statistically based POD curves for 42 stainless steel and 14 carbon steel performance cases. Subsequent comparisons of the POD fits for each of the cases showed that excellent NDE performance for fatigue cracks can be expected for ferritic materials. Very little difference was observed between the POD curves for the 14 carbon steel performance cases considered in this study and NDE performance could therefore be represented by a single POD curve. For stainless steel, very good performance can also be expected for circumferential cracks located on the same side of the weld from which the NDE examination is made. POD depended primarily on component thickness. Three POD curves for stainless steel were prepared. Best estimate and the associated 95% confidence bounds for POD versus through-wall depth logistic regression digital data are provided. Probabilistic fracture mechanics (PFM) calculations were performed to compare best estimate leak probabilities obtained from both the new performance-based POD curves and (sic). C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gosselin, SR (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 53 EP 64 PG 12 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900008 ER PT B AU Gosselin, SR Simonen, FA Carter, RG AF Gosselin, S. R. Simonen, F. A. Carter, R. G. GP ASME TI Flaw tolerance for multiple fatigue cracks SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB Appendix L of Section XI provides for serviceability assessments of piping components that are subject to fatigue stresses. This appendix introduced a damage tolerance examination strategy to assure that components perform reliably throughout operating periods between inspections. Operating periods are based on fatigue crack growth analyses of postulated pre-existing cracks. Evidence from service experience shows that fatigue cracking occurrences at operating nuclear power plants often result from mechanisms that cause cracks to initiate and then grow at multiple locations on the inside surface of a pipe, becoming longer and deeper, and eventually linking to form a single long crack. This paper documents important details of the technical bases for changes to Appendix L. Calculations identified aspect ratios for equivalent single cracks (ESQ between the extremes of a 6:1 ratio and a full circumferential crack that can be used in Appendix L flaw tolerance assessments to account for the initiation, growth, and linking of multiple fatigue cracks. Probabilistic fracture mechanics (PFM) calculations determined ESC aspect ratios that result in the same through-wall crack probability as multiple small cracks (0.02 inch depth) that initiate and coalesce. The computations considered two materials (stainless and low alloy steels), three pipe diameters, five cyclic membrane-to-gradient stress ratios and a wide range of primary loads. Subsequent deterministic calculations identified the ESC aspect ratio for the hypothetical reference flaw depth assumptions in Appendix L. This paper also describes computations that compare the Appendix L flaw tolerance allowable operating period for the ESC models with results obtained when a single default 6:1 aspect ratio reference flaw. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gosselin, SR (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 7 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 73 EP 86 PG 14 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900011 ER PT B AU Lam, PS Sindelar, RL Cheng, CM Stefek, TM Chao, YJ Elder, JB AF Lam, Poh-Sang Sindelar, Robert L. Cheng, Changmin Stefek, Tina M. Chao, Yuh J. Elder, James B., III GP ASME TI Stress corrosion cracking of carbon steel weldments SO PROCEEDINGS OF THE ASME PRESSURE VESSELS AND PIPING CONFERENCE 2005, VOL 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE GMAW; SCC; IGSCC; finite element analysis; welding simulation; residual stress; stress intensity factor; K-ISCC AB An experiment was conducted to investigate the role of weld residual stress on stress corrosion cracking in welded carbon steel plates prototypic to those used for nuclear waste storage tanks. Carbon steel specimen plates were butt-joined with Gas Metal Arc Welding technique. Initial cracks (seed cracks) were machined across the weld and in the heat affected zone. These specimen plates were then submerged in a simulated high level radioactive waste chemistry environment. Stress corrosion cracking occurred in the as-welded plate but not in the stress-relieved duplicate. A detailed finite element analysis to simulate exactly the welding process was carried out, and the resulting temperature history was used to calculate the residual stress distribution in the plate for characterizing the observed stress corrosion cracking. It was shown that the cracking can be predicted for the through-thickness cracks perpendicular to the weld by comparing the experimental K-ISCC to the calculated stress intensity factors due to the welding residual stress. The predicted crack lengths agree reasonably well with the test data. The final crack lengths appear to be dependent on the details of welding and the sequence of machining the seed cracks, consistent with the prediction. C1 Savannah River Natl Lab, Aiken, SC 29808 USA. RP Lam, PS (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 155 EP 163 PG 9 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900019 ER PT B AU Lam, PS Kim, Y Chao, YJ AF Lam, Poh-Sang Kim, Yil Chao, Yuh J. GP ASME TI Crack tip opening displacement and angle for a growing crack in carbon steel SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE CTOD; CTOA; J-R curve; J-A(2); finite element analysis; constraint effect; crack growth ID 2024-T351 ALUMINUM-ALLOY; TRIAXIALITY PARAMETER; HARDENING MATERIAL; FRACTURE; FIELDS; GROWTH; SHEET; CTOA; MICROTOPOGRAPHY; STATIONARY AB The crack tip opening displacements and angles (CTOD/CTOA) are calculated with finite element method based on the test data of a set of constraint-dependent J-R curves for A285 carbon steel. The values of the CTOD/CTOA are initially high at initiation, but rapidly decrease to a nearly constant value. When the common practice is adopted by using only the constant part of CTOD/CTOA as the fracture criterion, the crack growth behavior is shown to be severely underestimated. However, with a bilinear form of CTOD/CTCA fracture criterion which approximates the initial non-constant portion, the experimental load vs. crack extension curves can be closely predicted. Furthermore, it is demonstrated that the CTOD/CTOA is crack tip constraint dependent. The values of CTCD/CTOA for specimens with various ratios of crack length to specimen width (a/W) are reflected by the J-R curves and their slopes. C1 Savannah River Natl Lab, Aiken, SC 29808 USA. RP Lam, PS (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. NR 44 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 197 EP 204 PG 8 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900025 ER PT B AU Wang, JJA Wright, IG Lance, MJ Liu, KC AF Wang, John Jy-An Wright, Ian G. Lance, Michael J. Liu, Ken C. GP ASME TI Determination of interfacial fracture toughness for thin film coating materials SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE interface fracture toughness; thin film coating material; composite material; spiral notch; torsion test ID THERMAL BARRIER COATINGS; BIMATERIAL INTERFACES; MECHANISMS; STRESS; CRACKS; INSTABILITY; OXIDATION; STRENGTH; MODEL; OXIDE AB A material configuration of central importance in composite materials or in protective coating technology is a thin film of one material deposited onto a substrate of a different material. Fabrication of such a structure inevitably gives rise to stress in the film due to lattice mismatch, differing coefficient of thermal expansion, chemical reactions, or other physical effects. Therefore, in general, the weakest link in this composite system often resides at the interface between the thin film and substrate. In order to make multi-layered electronic devices and structural composites with long-term reliability, the fracture behavior of the material interfaces must be known. This project is intended to address the problems associated with interface fracture toughness evaluation and offers an innovative testing procedure for the determination of interface fracture toughness applicable to thin coating materials in general. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Wang, JJA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Lance, Michael/I-8417-2016; OI Lance, Michael/0000-0001-5167-5452; Wang, Jy-An/0000-0003-2402-3832 NR 38 TC 0 Z9 0 U1 0 U2 4 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 229 EP 238 PG 10 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900030 ER PT B AU Ren, WJ Rittenhouse, P AF Ren, Weiju Rittenhouse, Philip GP ASME TI Construction of web-accessible materials handbook for Generation IV nuclear reactors SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB The development of a web-accessible materials handbook in support of the materials selection and structural design for the Generation IV nuclear reactors is being planned. Background of the reactor program is briefly introduced. Evolution of materials handbooks for nuclear reactors over years is reviewed in light of the trends brought forth by the rapid advancement in information technologies. The framework, major features, contents, and construction considerations of the web-accessible Gen IV Materials Handbook are discussed. Potential further developments and applications of the handbook are also elucidated. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Ren, WJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, MS-6155,Bldg 4500-S, Oak Ridge, TN 37831 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 463 EP 467 PG 5 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900057 ER PT B AU Swindeman, RW Swindeman, MJ Ren, WJ AF Swindeman, Robert W. Swindeman, Michael. J. Ren, Weiju GP ASME TI A brief review of models representing creep of alloy 617 SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers ID BEHAVIOR; INCONEL-617; 1000-DEGREES-C; HELIUM AB Alloy 617 is being considered for the construction of components to operate in the Next Generation Nuclear Plant (NGNP). Service temperatures will range from 650 to 1000 degrees C. To meet the needs of the conceptual designers of this plant, a materials handbook is being developed that will provide information on alloy 617, as well as other materials of interest. The database for alloy 617 to be incorporated into the handbook was produced in the 1970s and 1980s, while creep and damage models were developed from the database for use in the design of high-temperature gas-cooled reactors. In the work reported here, the US database and creep models are briefly reviewed. The work reported represents progress toward a useful model of the behavior of this material in the temperature range of 650 to 1000 degrees C. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Swindeman, RW (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, MS-6155,Bldg 4500-S, Oak Ridge, TN 37831 USA. NR 35 TC 0 Z9 0 U1 0 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 469 EP 476 PG 8 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900058 ER PT B AU Ren, WJ AF Ren, Weiiju GP ASME TI Panel discussion of user requirements for the web-accessible Gen IV materials handbook SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Ren, WJ (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37830 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 477 EP 477 PG 1 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900059 ER PT B AU Marchi, CS Balch, DK Somerday, BP AF Marchi, C. San Balch, D. K. Somerday, B. P. GP ASME TI Effect of high-pressure hydrogen gas on fracture of austenitic steels SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers ID STACKING-FAULT ENERGY; STAINLESS-STEEL; EMBRITTLEMENT AB Applications requiring the containment and transport of hydrogen gas at pressures greater than 70 MPa are anticipated in the evolving hydrogen economy infrastructure. Since hydrogen is known to alter the mechanical properties of materials, data are needed to guide the selection of materials for structural components. The objective of this study is to characterize hydrogen-assisted fracture in two austenitic steels, 21Cr-6Ni-9Mn (21-6-9) and 22Cr-13Ni-5Mn (22-13-5), as well as explore the role of yield strength and small concentrations of ferrite on hydrogen-assisted fracture. The testing methodology involves exposure of uniaxial tensile specimens to high-pressure hydrogen gas in order to precharge the specimens with hydrogen, then subsequently testing the specimens to measure strength and ductility. In all cases, the alloys remained ductile despite precharging to hydrogen concentrations > 1 at%, this is substantiated by reduction in area of > 50% and fracture surfaces dominated by microvoid coalescence. Low concentrations of ferrite and moderate changes in yield strength did not affect the hydrogen-assisted fracture of 21-6-9 and 22-13-5 respectively. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Marchi, CS (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 483 EP 491 PG 9 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900062 ER PT B AU Gosselin, SR Simonen, FA Cumblidge, SE Tinsley, GA Lydell, B Anderson, MT Doctor, SR AF Gosselin, S. R. Simonen, F. A. Cumblidge, S. E. Tinsley, G. A. Lydell, B. Anderson, M. T. Doctor, S. R. GP ASME TI Assessment of ASME code examinations on regenerative, letdown and residual heat removal heat exchangers SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB Inservice inspection requirements for pressure retaining welds in the regenerative, letdown, and residual heat removal heat exchangers are prescribed in Section XI Articles IWB and IWC of the ASME Boiler and Pressure Vessel Code. Accordingly, volumetric and/or surface examinations are performed on heat exchanger shell, head, nozzle-to-head, and nozzle-to-shell welds. Inspection difficulties associated with the implementation of these Code-required examinations have forced operating nuclear power plants to seek relief from the U.S. Nuclear Regulatory Commission. The nature of these relief requests are generally concerned with metallurgical factors, geometry, accessibility, and radiation burden. Over 60% of licensee requests to the NRC identify significant radiation exposure burden as the principal reason for relief from the ASME Code examinations on regenerative heat exchangers. For the residual heat removal heat exchangers, 90% of the relief requests are associated with geometry and accessibility concerns. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gosselin, SR (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 661 EP 677 PG 17 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900082 ER PT B AU Ziomek-Moroz, M Flis, J AF Ziomek-Moroz, M. Flis, J. GP ASME TI Susceptibility of carbon steel to stress corrosion cracking in sodium hydroxide SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 6 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB Stress corrosion cracking susceptibility of carbon steel and decarburized steel was studied in 8.5 M sodium hydroxide at 100 degrees C. Potentiodynamic experiments were performed to determine the potential values to be applied in slow strain rate(ssr) experiments. Optical and scanning electron microcopy were used to investigate the surfaces of corroded samples. Severe intergranular stress corrosion cracking was observed on the carbon steel samples in comparison to the decarburized steel samples.. C1 US DOE, Albany Res Ctr, Albany, OR USA. RP Ziomek-Moroz, M (reprint author), US DOE, Albany Res Ctr, Albany, OR USA. NR 11 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4191-X J9 PRES VES P PY 2005 VL 6 BP 725 EP 728 PG 4 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BFO22 UT WOS:000243400900087 ER PT B AU Shah, VN AF Shah, V. N. (Vik) GP ASME TI Aging management and license renewal of pressure vessels, piping, components and structures - Introduction SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Shah, VN (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 3 EP 3 PG 1 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500001 ER PT B AU Clark, DT Jones, RL Valenti, LN AF Clark, D. T. Jones, R. L. Valenti, L. N. GP ASME TI Geologic and Environmental Probe System (GEOPS) SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB This paper describes the engineering design and development of a novel 2004 R&D 100 award winning probe system that is used to monitor and collect samples from within waste areas safely - without negative exposure to the environment or people. The Idaho National Laboratory (INL) has developed a multiple-use, low-cost subsurface probing system to safely sample and monitor targeted subsurface areas, from within and below abandoned or active landfills, mining areas, farms, airports, or from any of the more than 77,000 identified potentially hazardous waste sites across the U.S. The probe system uses a unique probe casing and tip system that-once placed in a zone of interest-accepts instrument inserts to provide invaluable potential contaminate transport or other data from saturated or unsaturated waste zones, or from groundwater zones. The Geologic and Environmental Probe System (GEOPS) is the newest generation of INL-developed subsurface probes. The system's robust probe casing platform is installed into or below a waste zone using direct push or sonic drill rigs, using a technique similar to pushing a needle into an apple. Subsurface conditions are not disturbed as in rotary drilling operations, cuttings are not brought to surface during installation, and workers and the surface environment are isolated from contaminants. One key to the capture of samples from the extremes of the subsurface using the GEOPS is the probe tip system. The specially designed tip utilizes a cylindrical section of sintered steel that has small pore openings and are used to filter liquid and gas samples from surrounding soil (i.e., area of interest) into the probe system. The sintered steel filter has reduced material properties, as compared to the probe casing platform and is vulnerable to high loadings, as would be experienced during probe installation. The probe tip system was specially designed to shield the filter component from large compressive and tensile loading and deliver it safely to a target depth. Once the casing is at the desired sampling depth, the instruments are placed into the platform, a vacuum is imposed on the system, and vapor and liquid subsurface samples are brought safely to surface though the sintered steel filter. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Clark, DT (reprint author), Idaho Natl Lab, 2525 N Fremont Ave,POB 1625, Idaho Falls, ID 83415 USA. NR 8 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 381 EP 389 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500051 ER PT B AU Smith, AC Gelder, LF Blanton, PS Lutz, RN AF Smith, Allen C. Gelder, Lawrence F. Blanton, Paul S. Lutz, Rex N. GP ASME TI Performance of a drum type packaging with urethane foam overpack subjected to crush and other regulatory tests SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB General Purpose Fissile Package (GPFP) prototypes of two configurations, 16 in. and 18 1/2 in. diameter drum overpacks, were subjected to the free-drop, crush, puncture, and thermal Hypothetical Accident Condition (HAC) sequential tests for 10CFR71, Type B packagings. The tests demonstrated that the prototypes are very robust, easily withstanding the structural tests. The tests also confirmed that the urethane foam-filled overpack was able to withstand the thermal test. C1 Westinghouse Savannah River Co, Savannah River Natl Lab, Aiken, SC 29808 USA. RP Smith, AC (reprint author), Westinghouse Savannah River Co, Savannah River Natl Lab, Aiken, SC 29808 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 421 EP 428 PG 8 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500056 ER PT B AU Blandford, RK Morton, DK Rahl, TE Snow, SD AF Blandford, R. K. Morton, D. K. Rahl, T. E. Snow, S. D. GP ASME TI Impact testing of stainless steel materials SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB Stainless steels are used for the construction of numerous spent nuclear fuel or radioactive material containers that may be subjected to high strains and moderate strain rates (10 to 200 per second) during accidental drop events. Mechanical characteristics of these materials under dynamic (impact) loads in the strain rate range of concern are not well documented. The goal of the work presented in this paper was to improve understanding of moderate strain rate phenomena on these materials. Utilizing a drop-weight impact test machine and relatively large test specimens (1/2-inch thick), initial test efforts focused on the tensile behavior of specific stainless steel materials during impact loading. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Blandford, RK (reprint author), Idaho Natl Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 463 EP 471 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500061 ER PT B AU Snow, SD Morton, DK Rahl, TE Blandford, RK Hill, TJ AF Snow, Spencer D. Morton, D. Keith Rahl, Tommy E. Blandford, Robert K. Hill, Thomas J. GP ASME TI Drop testing of doe spent nuclear fuel canisters SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB The National Spent Nuclear Fuel Program (NSNFP) at the Idaho National Engineering and Environmental Laboratory (INEEL) prepared four representative Department of Energy (DOE) spent nuclear fuel (SNF) canisters for the purpose of drop testing. The first two canisters represented a modified 24-inch diameter standardized DOE SNF canister and the second two canisters represented the Hanford Multi-Canister Overpack (MCO). The modified canisters and internals were constructed and assembled at the INEEL. The MCO internal weights were fabricated at the INEEL and assembled into two MCOs at Hanford and later shipped to the INEEL for drop test preparation. Drop testing of these four canisters was completed in August 2004 at Sandia National Laboratories. The modified canisters were dropped from 30 feet onto a flat, essentially unyielding surface, with the canisters oriented at 45 degrees and 70 degrees off-vertical at impact. One representative MCO was dropped from 23 feet onto the same flat surface, oriented vertically at impact. The second representative MCO was dropped onto the flat surface from 2 feet oriented at 60 degrees off-vertical. These drop heights and orientations were chosen to meet or exceed the Yucca Mountain repository drop criteria. This paper discusses the comparison of deformations between the actual dropped canisters and those predicted by pre-drop and limited post-drop finite element evaluations performed using ABAQUS/Explicit. Post-drop containment of all four canisters, demonstrated by way of helium leak testing, is also discussed. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Snow, SD (reprint author), Idaho Natl Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 473 EP 481 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500062 ER PT B AU Fix, DV Estill, JC Rebak, RB AF Fix, David V. Estill, John C. Rebak, Raul B. GP ASME TI Effect of samall variation in the composition of plates and weld filler wires on the general corrosion rate of Ni-Cr-Mo alloys SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE N06022; heat composition variability; corrosion rate; ASTM G 28A AB The ASTM standard B 575 provides the requirements for the chemical composition of Nickel-Chromium-Molybdenum (Ni-Cr-Mo) alloys such as Alloy 22 (N06022) and Alloy 686 (N06686). The compositions of each element are given in a range. For example, the content of Mo is specified from 12.5 to 14.5 weight percent for Alloy 22 and from 15.0 to 17.0 weight percent for Alloy 686. It was important to determine how the corrosion rate of welded plates of Alloy 22 using Alloy 686 weld filler metal would change if heats of these alloys were prepared using several variations in the composition of the elements even though still in the range specified in B 575. All the material used in this report were especially prepared at Allegheny Ludlum Co. Seven heats of plate were welded with seven heats of wire. Immersion corrosion tests were conducted in a boiling solution of sulfuric acid plus ferric sulfate (ASTM G 28 A) using both as-welded (ASW) coupons and solution heat-treated (SHT) coupons. Results show that the corrosion rate was not affected by the chemistry of the materials within the ranee of the standards. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Fix, DV (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave,L-631, Livermore, CA 94550 USA. OI Rebak, Raul/0000-0002-8070-4475 NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 483 EP 491 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500063 ER PT B AU Yilmaz, A Pasupathi, P Rebak, RB AF Yilmaz, Ahmet Pasupathi, Pasu Rebak, Raul B. GP ASME TI Stifling of crevice corrosion in alloy 22 during constant potential tests SO PROCEEDINGS OF THE ASME PRESSURE VESSELS AND PIPING CONFERENCE 2005, VOL 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE N06022; crevice corrosion; stifling; constant potential ID WASTE AB Artificially creviced Alloy 22 (N06022) is susceptible to crevice corrosion in presence of high chloride aqueous solution when high temperatures and high anodic potentials are applied. The presence of oxyanions in the electrolyte, especially nitrate, inhibits the nucleation and growth of crevice corrosion. Crevice corrosion may initiate when a constant potential above the crevice repassivation potential is applied. The occurrence of crevice corrosion can be divided into three characteristic domains: (1) nucleation, (2) growth and (3) stifling and arrest. That is, crevice corrosion reaches a critical stage after which growth stops and the specimens start to regain the passive behavior displayed before the nucleation of localized attack. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Yilmaz, A (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave,L-631, Livermore, CA 94550 USA. OI Yilmaz, Ahmet/0000-0001-6708-0672; Rebak, Raul/0000-0002-8070-4475 NR 24 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 493 EP 502 PG 10 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500064 ER PT B AU Yilmaz, A Fix, DV Estill, JC Rebak, RB AF Yilmaz, Ahmet Fix, David V. Estill, John C. Rebak, Raul B. GP ASME TI Correlation between two types of surface stress mitigation and the resistance to corrosion of Alloy 22 SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE stress mitigation; corrosion rate; N06022 AB When metallic plates are welded, residual tensile stresses may develop in the vicinity of the weld seam. Processes such as Low Plasticity Burnishing (LPB) and Laser Shock Peening (LSP) could be applied locally to eliminate the residual stresses produced by welding. In this study, Alloy 22 (N06022) plates were welded and then the above-mentioned surface treatments were applied to eliminate the residual tensile stresses. The aim of the current study was to compare the corrosion behavior of as-welded (ASW) plates with the corrosion behavior of plates with stress mitigated surfaces. Immersion and electrochemical tests were per-formed. Results show that the corrosion resistance of the mitigated plates was not affected by the surface treatments applied. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Yilmaz, A (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave,L-631, Livermore, CA 94550 USA. OI Yilmaz, Ahmet/0000-0001-6708-0672; Rebak, Raul/0000-0002-8070-4475 NR 17 TC 1 Z9 1 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 503 EP 509 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500065 ER PT B AU King, KJ Estill, JC Rebak, RB AF King, Kenneth J. Estill, John C. Rebak, Raul B. GP ASME TI Anodic behavior of specimens prepared from a full-diameter Alloy 22 fabricated container for nuclear waste SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE N06022; container fabrication; welding; corrosion rate; repassivation potential AB Alloy 22 (N06022) has been extensively tested for general and localized corrosion behavior both in the wrought and annealed condition and in the as-welded condition. The specimens for testing were mostly prepared from flat plates of material. It was important to determine if the process of fabricating a full diameter Alloy 22 container will affect the corrosion performance of the alloy. Specimens were prepared directly from a fabricated container and tested for corrosion resistance. Results show that both the anodic corrosion behavior and the localized corrosion resistance of specimens prepared from a welded fabricated container was the same as from flat welded plates. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP King, KJ (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave,L-631, Livermore, CA 94550 USA. OI Rebak, Raul/0000-0002-8070-4475 NR 10 TC 2 Z9 2 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 511 EP 519 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500066 ER PT B AU Aramayo, GA Ammerman, DJ Smith, JA AF Aramayo, Gustavo A. Ammerman, Douglas J. Smith, Jeffrey A. GP ASME TI Response of a dry storage spent fuel cask to hypothetical loading SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB This paper addresses the analytical methods used to determine the response of a dry storage spent fuel cask to hypothetical loading. Because of the sensitive nature of the topic under discussion, the response of the cask is described in qualitative terms, and the paper is intentionally vague on the parameters and results. This research was sponsored by the U.S. Nuclear Regulatory Commission (NRC) Spent Fuel Project Office. The work was performed under contract from the Sandia National Laboratory (SNL), Transportation Risk and Packing organization. The analytical effort was performed at the Oak Ridge National Laboratory (ORNL) facilities with loading specified by SNL. C1 Oak Ridge Natl Lab, Computat Mat Sci Grp, Oak Ridge, TN USA. RP Aramayo, GA (reprint author), Oak Ridge Natl Lab, Computat Mat Sci Grp, Oak Ridge, TN USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 527 EP 533 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500068 ER PT B AU Wu, TT Jones, WE Phifer, MA AF Wu, Tsu-te Jones, William E. Phifer, Mark A. GP ASME TI Quasi-static analysis for subsidence of stacked B-25 boxes SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB This paper presents a quasi-static technique to evaluate the structural deformation of the four stacked B-25 boxes subjected to the static loads of overlaying soil and to determine the effect of corrosion on the deformation. Although the boxes are subjected to a static load, the structural responses of the boxes vary with time. The analytical results indeed show that the deflection, buckling and post buckling of the components of the stacked boxes occur in sequence rather than simultaneously. Therefore, it is more appropriate to treat the problems considered as quasistatic rather than static; namely, the structural response of the stacked boxes are dynamic but with very long duration. Furthermore, the finite-element model has complex contact and slide conditions between the interfaces of the adjoining components, and thus its numerical solution is more tractable by using explicit time integration schemes. The analysis covers the three corrosion scenarios following various time lengths of initial burial under an interim soil cover. The results qualitatively agree with expected differences in deformation for different degrees of corrosion subsidence potential reduction that can be achieved. C1 Savannah River Natl Lab, Aiken, SC 29808 USA. RP Wu, TT (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 539 EP 544 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500070 ER PT B AU Wu, TT AF Wu, Tsu-te GP ASME TI Stress and sealing performance analysis of containment vessel SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB This paper presents a numerical technique for analyzing the containment vessel subjected to the combined loading of closure-bolt torque and internal pressure. The detailed stress distributions in the O-rings generated by both the torque load and the internal pressure can be evaluated by using this method. Consequently, the seating performance of the O-rings can be determined. The material of the O-rings can be represented by any available constitutive equation for hyperelastic material. In the numerical calculation of this paper, the form of the Mooney-Riviin strain energy potential is used. The technique treats both the preloading process of bolt tightening and the application of internal pressure as slow dynamic loads. Consequently, the problem can be evaluated using explicit numerical integration scheme. C1 Savannah River Natl Lab, Aiken, SC 29808 USA. RP Wu, TT (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 545 EP 549 PG 5 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500071 ER PT B AU Daugherty, WL Vormelker, PR AF Daugherty, W. L. Vormelker, P. R. GP ASME TI Mechanical properties of fiberboard overpack materials in the 9975 shipping package SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE cane fiberboard; compressive strength; environmental conditioning AB Many radioactive material (RAM) shipping packages incorporate cane fiberboard overpacks for thermal insulation and impact resistance. Mechanical strength (tensile and compressive) has been measured on cane fiberboard and a similar wood-based product following short-term conditioning in several temperature/humidity environments. Both products show similar trends and vary in behavior with fiber orientation, temperature and humidity. A memory effect also exists where original strength values are only partially recovered following exposure to a degrading environment and return to ambient conditions. C1 Savannah River Natl Lab, Aiken, SC 29808 USA. RP Daugherty, WL (reprint author), Savannah River Natl Lab, POB 616, Aiken, SC 29808 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 551 EP 557 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500072 ER PT B AU Vormelker, PR Daugherty, WL AF Vormelker, P. R. Daugherty, W. L. GP ASME TI Thermal properties of fiberboard overpack materials in the 9975 shipping package SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB The 9975 shipping package incorporates a cane fiberboard overpack for thermal insulation and impact resistance. Thermal properties (thermal conductivity and specific heat capacity) have been measured on cane fiberboard and a similar wood fiber-based product at several temperatures representing potential storage conditions. While the two products exhibit similar behavior, the measured specific heat capacity varies significantly from prior data. The current data are being developed as the basis to verify that this material remains acceptable over the extended storage time period. C1 Savannah River Natl Lab, Aiken, SC 29808 USA. RP Vormelker, PR (reprint author), Savannah River Natl Lab, POB 616, Aiken, SC 29808 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 559 EP 566 PG 8 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500073 ER PT B AU Etien, RA Gordon, SR Ilevbare, GO AF Etien, R. A. Gordon, S. R. Ilevbare, G. O. GP ASME TI Effect of solution annealing on critical potentials of alloy 22 SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers ID 18-8 STAINLESS STEEL AB The effect of solution annealing on localized corrosion resistance of Alloy 22 was studied in electrolytes of varying composition. The experiments were carried out on Alloy 22 specimens with the resultant thick dark brown oxide film from the solution annealing process still intact. The effect of solution annealing on the localized corrosion resistance of Alloy 22 was found to be electrolyte specific within the temperature range investigated. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Etien, RA (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave,L-631, Livermore, CA 94550 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 575 EP 582 PG 8 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500075 ER PT B AU Farmer, JC Haslam, JJ Day, SD Branagan, DJ Blue, CA Rivard, JDK Aprigliano, LF Yang, N Perepezko, JH Beardsley, MB AF Farmer, J. C. Haslam, J. J. Day, S. D. Branagan, D. J. Blue, C. A. Rivard, J. D. K. Aprigliano, L. F. Yang, N. Perepezko, J. H. Beardsley, M. B. GP ASME TI Corrosion characterization of iron-based high-performance amorphous-metal thermal-spray coatings SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers ID RESISTANCE; ALLOYS AB New corrosion-resistant, iron-based amorphous metals have been identified from published data or developed through combinatorial synthesis, and tested to determine their relative corrosion resistance. Many of these materials can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS # N06022) in some very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. One of these compositions, SAM1651, is discussed in detail to illustrate the promise of this general class of materials. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Farmer, JC (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 14 TC 5 Z9 5 U1 3 U2 6 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 583 EP 589 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500076 ER PT B AU El-Dasher, BS Torres, SG AF El-Dasher, Bassern S. Torres, Sharon G. GP ASME TI Second phase precipitation in as-welded and solution annealed alloy 22 welds SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE N06022; electron backscatter diffraction; TCP phases AB The precipitation characteristics of tetrahedrally close-packed (TCP) phases during the welding and the subsequent solution annealing process of Alloy 22 1 1/2" thick plate double-U prototypical welds are investigated. Electron backscatter diffraction (EBSD) was used to provide large scale microstructural observation of the weld cross section, and scanning electron microscopy (SEM) was used to map the location of the TCP phases. Analysis shows that TCP precipitation occurs congruent to the weld passes, with the solution annealing reducing the sizes of coarser precipitates. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP El-Dasher, BS (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave,L-631, Livermore, CA 94550 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 591 EP 595 PG 5 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500077 ER PT B AU Hafner, RS AF Hafner, Ronald S. GP ASME TI Development of US regulations for the transportation of radioactive materials: A look back over the past 40 years SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers C1 Lawrence Livermore Natl Lab, Livermore, CA USA. RP Hafner, RS (reprint author), Lawrence Livermore Natl Lab, Livermore, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 599 EP 599 PG 1 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500079 ER PT B AU Shah, VN Shelton, B Fabian, R Tam, SW Liu, YY Shuler, J AF Shah, V. N. Shelton, B. Fabian, R. Tam, S. W. Liu, Y. Y. Shuler, J. GP ASME TI Training in the application of the ASME code to transportation packaging of radioactive materials SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB The Department of Energy has established guidelines for the qualifications and training of technical experts preparing and reviewing the safety analysis report for packaging (SARP) and transportation of radioactive materials. One of the qualifications is a working knowledge of, and familiarity with the ASME Boiler and Pressure Vessel Code, referred to hereafter as the ASME Code. DOE is sponsoring a course on the application of the ASME Code to the transportation packaging of radioactive materials. The course addresses both ASME design requirements and the safety requirements in the federal regulations. The main objective of this paper is to describe the salient features of the course, with the focus on the application of Section III, Divisions 1 and 3, and Section VIII of the ASME Code to the design and construction of the containment vessel and other packaging- components used for transportation (and storage) of radioactive materials, including spent nuclear fuel and high-level radioactive waste. The training course includes the ASME Code-related topics that are needed to satisfy all Nuclear Regulatory Commission (NRC) requirements in Title 10 of the Code of Federal Regulation Part 71 (10 CFR 71). Specifically, the topics include requirements for materials, design, fabrication, examination, testing, and quality assurance for containment vessels, bolted closures, components to maintain subcriticality, and other packaging components. The design addresses thermal and pressure loading, fatigue, nonductile fracture and buckling of these components during both normal conditions of transport and hypothetical accident conditions described in 10 CFR 71. Various examples are drawn from the review of certificate applications for Type B and fissile material transportation packagings. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Shah, VN (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 601 EP 612 PG 12 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500080 ER PT B AU Fabian, R Garrison, L Shelton, B Liaw, J Shah, V Tam, SW Liu, YY Shuler, J AF Fabian, R. Garrison, L. Shelton, B. Liaw, J. Shah, V. Tam, S. W. Liu, Y. Y. Shuler, J. GP ASME TI Training in quality assurance for radioactive material transportation packaging SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB The Department of Energy (DOE) has established guidelines for qualifications and training of the technical experts preparing and reviewing the safety analysis reports for packaging (SARP) and transportation of radioactive materials. One of the qualifications is working knowledge of, and familiarity with the quality assurance (QA) requirements in Subpart H of Title 10 of the Code of Federal Regulations Part 71. DOE is sponsoring a course on quality assurance for radioactive material transportation packaging. The objective of this paper is to describe the salient features of the course, the purpose of which is to provide QA training and practical experience that are required to develop and implement a QA plan or prepare the QA chapter of a SARP for the design, fabrication, assembly, testing, maintenance, repair, modification, and use of the packaging. The applicable QA requirements from DOE orders, federal regulations, and NRC regulatory guides will be highlighted, along with a graded approach to selected QA elements from Subpart H of 10 CFR Part 71. The paper will also briefly discuss ASME NQA-1 for Type B and fissile material packaging, current issues resulting from the different emphasis between a compliance-based QA program (in Subpart H, 10 CFR 71) for packaging and a performance-based QA program for DOE nuclear facilities (based on 10 CFR 830, "Nuclear Safety Management"), and the final rule changes in 10 CFR 71 that became effective on October 1, 2004. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Fabian, R (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 613 EP 620 PG 8 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500081 ER PT B AU Ammerman, D Stevens, D Barsotti, M AF Ammerman, Doug Stevens, Dave Barsotti, Matt GP ASME TI Numerical analyses of locomotive impacts on a spent fuel truck cask and trailer SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB During the transportation of spent nuclear fuel by truck, the possibility exists that a train could run into the spent fuel cask at a grade crossing. Sandia National Laboratories has conducted a numerical study to assess the possibility of cask breach or material release in the event of a high-speed, broadside locomotive collision. A numerical approach has the advantage over conducting a physical test as was done in the 1970s [1] in that varying parameters can be examined. For example, one of the criticisms of the 1970s test was the height of the cask. In the test, the centerline of the cask was above the main frame-rails of the locomotive. In this study the position of the cask with respect to the locomotive was varied. The response of the cask and trailer in different collision scenarios was modeled numerically with LS-DYNA [2]. The simulations were performed as a collaborative endeavor between Sandia National Laboratories (SNL), Applied Research Associates, Inc. (ARA) and Foster-Miller, Inc (FMI). ARA developed the GA-4 Spent Fuel Cask and Cask Transporter models described in this report. These models were then combined with two existing FMI heavy freight locomotive finite element models to create the overall simulation scenarios. The modeling effort, results, and conclusions are presented in this paper. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ammerman, D (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 621 EP 628 PG 8 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500082 ER PT B AU Boles, JL Hafner, RS Fischer, LE AF Boles, Jason L. Hafner, Ronald S. Fischer, Larry E. GP ASME TI Neutron source strength estimates from (alpha, n) reactions in binary mixtures of actinide particles and light element particles SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers C1 Lawrence Livermore Natl Lab, Risk & Response Management Program, Livermore, CA 94550 USA. RP Boles, JL (reprint author), Lawrence Livermore Natl Lab, Risk & Response Management Program, POB 808, Livermore, CA 94550 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 629 EP 638 PG 10 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500083 ER PT B AU Fillmore, DL Winston, PL Morton, SL Hoffman, CR Van Ausdeln, LA Saegusa, T Shirai, K Hattori, T Sasahara, A AF Fillmore, Denzel L. Winston, Philip L. Morton, Sheryl L. Hoffman, Cecelia R. Van Ausdeln, Leo A. Saegusa, Toshiari Shirai, Koji Hattori, Takatoshi Sasahara, Akihiro GP ASME TI The long-term performance of concrete in nuclear applications SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 7 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers DE concrete; nuclear applications; spent nuclear fuel; VSC-17; storage AB The Idaho National Laboratory investigated long-term concrete performance for nuclear applications. Scientists searched the open literature for information on the effects of heat and radiation. They also examined the concrete shield of the Pacific Sierra Nuclear Ventilated Storage Cask (VSC-17) for concrete deterioration and loss of shieldinf. The literature search revealed that low doses, < 10(9) n/cm(2) or < 10(11) Rad gamma, of radiation over periods less than 50 years do not appear to significantly affect concrete. Exposure over 100 years was not studied. The effects of higher doses of radiation are not as clear. Generally, the threshold of degradation is 95 degrees C, and degradation increases with increasing temperature and time. In 15 years of VSC-17 use, there is no apparent effect from environment, radiation, or temperature that has adversely affected the shielding or structural functions, although there has been some minor cracking of the concrete. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Fillmore, DL (reprint author), Idaho Natl Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 8 TC 1 Z9 1 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4192-8 J9 PRES VES P PY 2005 VL 7 BP 639 EP 648 PG 10 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BFO14 UT WOS:000243398500084 ER PT B AU Xu, J Miller, C Hofmayer, C Graves, H AF Xu, J. Miller, C. Hofmayer, C. Graves, H. GP ASME TI The significance of nonlinear characteristics on the seismic induced pressures of deeply embedded NPP structures SO Proceedings of the ASME Pressure Vessels and Piping Conference 2005, Vol 8 SE PRESSURE VESSEL AND PIPING DIVISION OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 17-21, 2005 CL Denver, CO SP Amer Soc Mech Engineers AB The conventional approach for treating the soil-structure interaction (SSI) effect is to apply various linear methodologies (e.g., substructure and direct methods). In the absence of any major nonlinear effect, linear methodology is sufficient to capture the SSI response parameters. However, for situations where structures are deeply embedded and/or buried (DEB) below grade and a sizeable inertial effect must be considered, the nonlinearity induced by the interaction at the soil/structure interface may potentially influence the SSI response. This is especially true for the seismic induced soil pressures. The effect of such nonlinear characteristics on SSI methodologies should be assessed to determine the extent to which the nonlinearity associated with DEB structures needs to be modeled. Sponsored by the US Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) is carrying out a research program to develop a technical basis to support the safety evaluation of deeply embedded and/or buried (DEB) structures as proposed for advanced reactor designs. In this paper, a study of the effect of the soil/structure interface on seismic induced pressures is presented. The nonlinear effect considered includes separation or slipping along the side soil/wall interface. This paper describes various finite element models developed using the LS-DYNA computer code to study the nonlinear effect associated with the soil/structure interface interaction of DEB structures subjected to seismic motion. It is found, based on results to date, that the seismic response characteristics of DEB structures are considerably influenced by the modeling technique for soil/structure interfaces. One of the prominent effects found is the soil/structure interface separations, which modify the soil pressure distributions in both circumferential and vertical directions, as well as their frequency content. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Xu, J (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 9 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4193-6 J9 PRES VES P PY 2005 VL 8 BP 35 EP 45 PG 11 WC Engineering, Civil; Engineering, Mechanical SC Engineering GA BFO16 UT WOS:000243399500005 ER PT B AU Visher, RJ Gast, L Ellingson, WA Feuerstein, A AF Visher, Robert J. Gast, Luis Ellingson, William A. Feuerstein, Albert GP ASME TI Health monitoring and life prediction of thermal barrier coatings using a laser-based method SO Proceedings of the ASME Turbo Expo 2005, Vol 1 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers DE non-destructive testing; thermal barrier coatings; gas turbines; laser scattering AB Thermal barrier coatings (TBCs) are a critical component in low-emission gas turbines. A reliable method is required to monitor the condition of the TBC and predict coating failure. The condition of the interface between the metallic bond coat and TBC has been shown to be a potential indicator of spallation. The TBC is optically translucent; therefore, the bond coat/TBC interface can be probed using laser light with a wavelength of 0.632 microns or higher. A laser system in an optical backscatter configuration has been used to investigate several yttria-stabilized zirconia (YSZ) TBCs applied with either electron-beam physical vapor deposition (EB-PVD) or air plasma spraying (APS). The TBCs were thermally cycled for one hour increments until failure and investigated by the laser backscatter method after set numbers of thermal cycles. Correlations have been established between laser backscatter data and the number of thermal cycles, suggesting that the laser backscatter method can be used to predict failure. A theoretical model has been used to compare interface topography scatter to experimental results. This paper will discuss the laser backscatter technique and the experimental results and will compare the experimental data and theoretical scatter. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Visher, RJ (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4699-7 PY 2005 BP 259 EP 266 PG 8 WC Engineering, Aerospace; Engineering, Mechanical; Materials Science, Ceramics SC Engineering; Materials Science GA BFN84 UT WOS:000243375800031 ER PT B AU Kirby, GH Cooley, KM Armstrong, BL AF Kirby, Glen H. Cooley, Kevin M. Armstrong, Beth L. GP ASME TI Tailored rheological behavior of mullite and bsas suspensions using a cationic polyelectrolyte SO Proceedings of the ASME Turbo Expo 2005, Vol 1 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers ID ENVIRONMENTAL BARRIER COATINGS; SILICON-CARBIDE; WATER-VAPOR; MOLECULAR DIMENSIONS; STABILITY; OXIDATION; TEMPERATURE; PRESSURE AB The effects of a cationic polyelectrolyte, polyethylenimine, on the theological behavior of aqueous mullite and celsian phase, barium strontium aluminosilicate (BSAS) suspensions have been studied to optimize a dip-coating process. The surface of the ceramic particles was characterized in aqueous media using zeta potential measurements. The ionization behavior and hydrodynamic radius of polyethylenimine in aqueous media was characterized by potentiometric titration and dynamic light scattering measurements, respectively. The theological behavior of concentrated ceramic suspensions containing polyethylenimine was characterized by stress viscometry and elastic modulus measurements. Polyethylenimine imparts repulsive, electrosteric interactions between mullite and BSAS particles in aqueous suspension, resulting in shear thinning flow behavior, linear elastic moduli, and yield stress values that are minimized for suspensions with a critical PEI concentration of 0.2 mg PEI per m(2) of mullite and 0.4 mg PEI per m(2) of BSAS, respectively. The elastic moduli and yield stress of mullite and BSAS suspensions were nearly identical at equivalent fractions of their critical PEI concentration. Uniform coatings were obtained upon dipping SiC, Si3N4, and Si-metal substrates into shear-thinning suspensions containing PEI at 81-88% of the critical concentration. Dense mullite coatings were demonstrated on SiC substrates after sintering at 1400 degrees C. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Kirby, GH (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Armstrong, Beth/E-6752-2017 OI Armstrong, Beth/0000-0001-7149-3576 NR 26 TC 0 Z9 0 U1 0 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4699-7 PY 2005 BP 307 EP 313 PG 7 WC Engineering, Aerospace; Engineering, Mechanical; Materials Science, Ceramics SC Engineering; Materials Science GA BFN84 UT WOS:000243375800037 ER PT B AU Tortorelli, PF More, KL AF Tortorelli, Peter F. More, Karren L. GP ASME TI Use of very high water-vapor pressures to evaluate candidate compositions for environmental barrier coatings SO Proceedings of the ASME Turbo Expo 2005, Vol 1 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers ID SIO2 SCALE VOLATILITY; SILICON-CARBIDE; COMBUSTION CONDITIONS; RECESSION; OXIDATION; CERAMICS; MODEL AB Environmental barrier coatings (EBCs) are used to protect Si-based ceramics from accelerated oxidation and volatilization in the presence of elevated water-vapor pressures at high temperatures and high gas velocities. Previously, an analysis based on mass flux of volatilized species has shown that operating at very high H2O pressures can be used to compensate for the low gas velocities found in many laboratory exposure facilities so as to conduct first-stage screening of EBC compositions for volatility resistance. To test this prediction experimentally, a high-temperature furnace was modified to accommodate as pressures of up to 20 atm and bulk specimens of barium-strontium aluminosilicate (BSAS), barium aluminosilicate (BAS), and strontium aluminosilicate (SAS), silica (SiO2), and silicon carbide (SiC) were exposed at 1250 degrees C in 90% H2O-10% air. This set of materials provided an adequate spread in susceptibility to volatilization to evaluate the proposed approach because BSAS, BAS, and SAS are significantly more volatilization resistant in water-bearing environments than SiO2 and Si-bearing ceramics (such as SiC) that form silica under these conditions. The gravimetric results provided clear trends in volatilization resistance. The three aluminosilicates exhibited similar kinetic behavior and had significantly lower rates of mass losses than the SiO2 and SiC. These findings provided the experimental proof-of-principle for using high-pressure, low-gas-velocity exposures for qualitative differentiation of decrees of volatilization resistance among different candidate materials being developed for EBC applications. C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Tortorelli, PF (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN USA. RI More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 21 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4699-7 PY 2005 BP 363 EP 367 PG 5 WC Engineering, Aerospace; Engineering, Mechanical; Materials Science, Ceramics SC Engineering; Materials Science GA BFN84 UT WOS:000243375800043 ER PT B AU More, KL Lara-Curzio, E Tortorelli, PF Brummett, TM Szweda, A AF More, Karren L. Lara-Curzio, Edgar Tortorelli, Peter F. Brummett, Tracie M. Szweda, Andy GP ASME TI The high-temperature stability of an oxide/oxide composite at high water-vapor pressure SO Proceedings of the ASME Turbo Expo 2005, Vol 1 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers ID CERAMIC-MATRIX COMPOSITES; SURFACE-ROUGHNESS; RECESSION; OXIDATION; BEHAVIOR; EXPOSURE; FIBERS AB The microstructural and mechanical stabilities of a Nextel 720 (alumina+mullite) fiber-reinforced, alumina matrix composite were evaluated following exposure of the material to a high H2O pressure (to simulate a gas turbine combustor environment) in Oak Ridge National Laboratory's (ORNL's) high temperature, high pressure facility (Keiser Rigs). Coupons were exposed at 1135 degrees C and 1200 degrees C in a high-pressure (10 atm) furnace containing 10% water vapor for 1000, 2000. and 3000 h. Extensive microstructural characterization was conducted after each exposure to evaluate fiber and matrix stabilities as a function of exposure time and temperature. Retained tensile strengths were also measured and compared to baseline properties following each exposure. It was found that there was no significant change in the composite microstructure or tensile strength after long-term exposure in the Keiser Rig at 1135 degrees C, whereas significant Nextel 720 fiber degradation (grain growth and increased surface roughness) occurred during exposure for 3000 h at 1200 degrees C. Statistical variations in the mean strength values between the as-processed and exposed composites indicated little change in strength. however. The composite degradation was primarily thermal and the addition of H2O had little effect on changing or accelerating these effects. C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. RP More, KL (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN USA. RI More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 24 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4699-7 PY 2005 BP 369 EP 374 PG 6 WC Engineering, Aerospace; Engineering, Mechanical; Materials Science, Ceramics SC Engineering; Materials Science GA BFN84 UT WOS:000243375800044 ER PT B AU Pint, BA AF Pint, Bruce A. GP ASME TI The effect of water vapor on Cr depletion in advanced recuperator alloys SO Proceedings of the ASME Turbo Expo 2005, Vol 1 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers ID OXIDATION BEHAVIOR; CHROMIUM AB Durable alloy foils are needed for gas turbine recuperators operating at 650 degrees-700 degrees C. It has been established that water vapor in the exhaust gas causes more rapid consumption of Cr in austenitic stainless steels leading to a reduction in operating lifetime of these thin-walled components. Laboratory testing at 650 degrees-800 degrees C of commercial and model alloys is being used to develop a better understanding of the long-term rate of Cr consumption in these environments. Results are presented for commercial alloys 709. 120 and 625. After 10,000h exposures at 650 degrees and 700 degrees C in humid air, grain boundary Cr depletion was observed near the surface of all these materials. In the Fe-base alloys, 709 and 120, this depletion led to localized Fe-rich nodule formation. This information then can be used to develop low-cost alternatives to currently available candidate materials. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Pint, BA (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RI Pint, Bruce/A-8435-2008 OI Pint, Bruce/0000-0002-9165-3335 NR 26 TC 1 Z9 1 U1 0 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4699-7 PY 2005 BP 927 EP 934 PG 8 WC Engineering, Aerospace; Engineering, Mechanical; Materials Science, Ceramics SC Engineering; Materials Science GA BFN84 UT WOS:000243375800104 ER PT B AU Lara-Curzio, E Trejo, R More, KL Maziasz, PJ Pint, BA AF Lara-Curzio, Edgar Trejo, R. More, K. L. Maziasz, P. J. Pint, B. A. GP ASME TI Evaluation and characterization of iron- and nickel-based alloys for microturbine recuperators SO Proceedings of the ASME Turbo Expo 2005, Vol 1 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers AB The effects of stress, temperature and time of exposure to microturbine exhaust gases on the mechanical properties and corrosion resistance of alloys HR-1208 and 230 (R) was investigated at turbine exhaust temperatures between 620 degrees C and 760 degrees C. It was found that the ultimate tensile strength and ductility of alloy 230 (R) decreased by 30% and 60%, respectively, after 500 hours exposure at 752 degrees C. At the lowest exposure temperature of 679 degrees C the ultimate tensile strength and ductility decreased by 10% and 25%, respectively. The ultimate tensile strength and ductility of HR-1208 alloy decreased by 15% and 50%, respectively, after 500 hours exposure at 745 degrees C. At the lowest exposure temperature of 632 degrees C the ultimate tensile strength and ductility decreased by 10% and 23%. respectively. The microstructural changes associated with exposure to microturbine exhaust gases are analyzed and discussed. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Lara-Curzio, E (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RI Pint, Bruce/A-8435-2008; More, Karren/A-8097-2016; OI Pint, Bruce/0000-0002-9165-3335; More, Karren/0000-0001-5223-9097; Maziasz, Philip/0000-0001-8207-334X NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4699-7 PY 2005 BP 945 EP 961 PG 17 WC Engineering, Aerospace; Engineering, Mechanical; Materials Science, Ceramics SC Engineering; Materials Science GA BFN84 UT WOS:000243375800106 ER PT B AU Maziasz, PJ Shingledecker, JP Pint, BA Evans, ND Yamamoto, Y More, K Lara-Curzio, E AF Maziasz, Philip J. Shingledecker, John P. Pint, Bruce A. Evans, Neal D. Yamamoto, Yukinori More, Karren Lara-Curzio, Edgar GP ASME TI Overview of creep strength and oxidation of heat-resistant alloy sheets and foils for compact heat-exchangers SO Proceedings of the ASME Turbo Expo 2005, Vol 1 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers AB The Oak Ridge National Laboratory (ORNL) has been involved in research and development related to improved performance of recuperators for industrial gas turbines since about 1996, and in improving recuperators for advanced microturbines since 2000. Recuperators are compact, high efficiency heat-exchangers that improve the efficiency of smaller gas turbines and microturbines. Recuperators were traditionally made from 347 stainless steel and operated below or close to 650 degrees C, but today are being designed for reliable operation above 700 degrees C. The Department of Energy (DOE) sponsored programs at ORNL have helped defined the failure mechanisms in stainless steel foils, including creep due to fine grain size, accelerated oxidation due to moisture in the hot exhaust gas, and loss of ductility due to aging. ORNL has also been involved in selecting and characterizing commercial heat-resistant stainless alloys, like HR120 or the new AL20-25+Nb, that should offer dramatically improved recuperator capability and performance at a reasonable cost. This paper summarizes research on sheets and foils of such alloys over the last few years, and suggests the next likely stages for manufacturing recuperators with upgraded performance for the next generation of larger 200-250 kW advanced microturbines. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Maziasz, PJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RI Evans, Neal/F-5955-2011; Pint, Bruce/A-8435-2008; More, Karren/A-8097-2016; OI Pint, Bruce/0000-0002-9165-3335; More, Karren/0000-0001-5223-9097; Maziasz, Philip/0000-0001-8207-334X NR 40 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4699-7 PY 2005 BP 1011 EP 1022 PG 12 WC Engineering, Aerospace; Engineering, Mechanical; Materials Science, Ceramics SC Engineering; Materials Science GA BFN84 UT WOS:000243375800113 ER PT B AU Spadaccini, CM Peck, J Waitz, IA AF Spadaccini, C. M. Peck, J. Waitz, I. A. GP ASME TI Catalytic combustion systems for micro-scale gas turbine engines SO Proceedings of the ASME Turbo Expo 2005, Vol 2 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers AB As part of an ongoing effort to develop a micro-scale gas turbine engine for power generation and micropropulsion applications, this paper presents the design, modeling, and experimental assessment of a catalytic combustion system. Previous work has indicated that homogenous gas-phase microcombustors are severely limited by chemical reaction time-scales. Storable hydrocarbon fuels, such as propane, have been shown to blowout well below the desired mass flow rate per unit volume. Heterogeneous catalytic combustion has been identified as a possible improvement. Surface catalysis can increase hydrocarbon-air reaction rates, improve ignition characteristics, and broaden stability limits. Several radial inflow combustors were micromachined from silicon wafers using Deep Reactive Ion Etching (DRIE) and aligned fusion wafer bonding. The 191 mm(3) combustion chambers were filled with platinum coated foam materials of various porosity and surface area. For near stoichiometric propane-air mixtures, exit gas temperatures of 1100 K were achieved at mass flow rates in excess of 0.35 g/s. This corresponds to a power density of approximately 1200 MW/m(3); an 8.5-fold increase over the maximum power density achieved for gas-phase propane-air combustion in a similar geometry. Low order models including time-scale analyses and a one-dimensional steady-state plugflow reactor model, were developed to elucidate the underlying physics and to identify important design parameters. High power density catalytic microcombustors were found to be limited by the diffusion of fuel species to the active surface, while substrate porosity and surface area-to-volume ratio were the dominant design variables. C1 Lawrence Livermore Natl Lab, Ctr Micro & Nano Technol, Livermore, CA 94551 USA. RP Spadaccini, CM (reprint author), Lawrence Livermore Natl Lab, Ctr Micro & Nano Technol, POB 808,L-223,7000 East Ave, Livermore, CA 94551 USA. NR 23 TC 0 Z9 0 U1 1 U2 5 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4725-X PY 2005 BP 259 EP 274 PG 16 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN85 UT WOS:000243376400024 ER PT B AU Sidwell, T Casleton, K Straub, D Maloney, D Richards, G Strakey, P Ferguson, D Beer, S AF Sidwell, T. Casleton, K. Straub, D. Maloney, D. Richards, G. Strakey, P. Ferguson, D. Beer, S. GP ASME TI Development and operation of a pressurized optically-accessible research combustor for simulation validation and fuel variability studies SO Proceedings of the ASME Turbo Expo 2005, Vol 2 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers ID PASSIVE CONTROL; DYNAMICS AB The U.S. Department of Energy Turbines Program has established very stringent NOx emissions goals of less than 3 ppmv for future turbine power generation. These future turbine power plants may operate on hydrogen-rich fuels, such as coalderived synthesis gas (syngas), or pure hydrogen derived from shifting the syngas. Achieving these goals is expected to require improved combustor concepts which may be dramatically different than current combustor designs. Significant and costly experimental testing is usually required to assess new combustor concepts. Ideally, new concepts could be evaluated with numeric simulations to reduce development time and cost. However, current simulation capabilities are not sufficient to reliably capture the effects of fuel variations on flame extinction, emissions levels, and dynamic stability. Furthermore, very little data with controlled boundary conditions are available to check numeric predictions at actual turbine engine conditions, or simply to assess combustor performance without ambiguous boundary conditions. This paper presents a description of the development and operation of an optically-accessible research combustor, which is designed to provide fundamental combustion data at elevated pressure and inlet air temperature, and with precisely determined thermal, acoustic, and flow boundary conditions. The effects of fuel composition variations are investigated by blending of controlled quantities of hydrogen with natural gas. Recent test results-emissions data, dynamics data, and heat losses for hydrogen addition from 0 to 40% by fuel volume at two combustor pressures-and a description of future testing are also presented. The results show that the addition of hydrogen to natural gas in percentages as low as 5% of total fuel volume can significantly decrease the lean extinction limit, and promote stable operation at lower equivalence ratios while promoting lower NOx emissions. Dynamic pressures were measured, but combustion dynamics were not present due to the combustor configuration. The effect of heat losses on flame temperature and emissions were quantified. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV USA. RP Sidwell, T (reprint author), US DOE, Natl Energy Technol Lab, Morgantown, WV USA. NR 18 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4725-X PY 2005 BP 537 EP 543 PG 7 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN85 UT WOS:000243376400051 ER PT B AU Tucker, D Lawson, L Gernmen, R Dennis, R AF Tucker, David Lawson, Larry Gernmen., Randy Dennis, Richard GP ASME TI Evaluation of hybrid fuel cell turbine system startup with compressor bleed SO Proceedings of the ASME Turbo Expo 2005, Vol 5 LA English DT Proceedings Paper CT 50th ASME Turbo-Expo CY JUN 06-09, 2005 CL Reno, NV SP Amer Soc Mech Engineers ID PART-LOAD PERFORMANCE AB Current design concepts for hybrid systems call for the use of presently available turbine systems. Simply stated, the combustor of a turbine system is replaced with a high temperature fuel cell whose excess heat is used to drive the turbine. However, the startup of a turbine in such a direct fired fuel cell turbine hybrid system is made problematic through the increased pressure losses introduced by heat recuperation, and the relatively large cathode volume now present between the compressor discharge and the turbine inlet. This work evaluates the use of compressor bleed air to avoid stall and surge during the startup of a fuel cell turbine hybrid power system using the Hybrid Performance (Hyper) project hardware simulation facility at the National Energy Technology Laboratory (NETL), U.S. Department of Energy. Because integration of a fuel cell and often multiple recuperators into the compressed air stream results in a higher required pressure ratio for any given compressor inlet mass flow, a strategy must be developed to avoid compressor stall during startup. Turbine starts were attempted using the NETL Hyper project facility over a range of compressor bleed mass flows. The experimental facility at NETL makes use of a natural gas burner controlled by a real time fuel cell model to simulate the thermal output of a solid oxide fuel cell. Pressure vessels, used for simulating the cathode and post combustion volumes, and exhaust gas recuperators are integrated into the system with a modified turbine and compressor on a single shaft. The startup profiles are compared to the stall line of the compressor map to quantitatively evaluate the efficacy of the applied method in avoiding stall and surge during startup events. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP Tucker, D (reprint author), US DOE, Natl Energy Technol Lab, 3610 Collins Ferry Rd, Morgantown, WV 26507 USA. NR 23 TC 2 Z9 2 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 0-7918-4728-4 PY 2005 BP 333 EP 341 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BFN87 UT WOS:000243376900035 ER PT J AU Miller, JA Pilling, MJ Troe, E AF Miller, JA Pilling, MJ Troe, E TI Unravelling combustion mechanisms through a quantitative understanding of elementary reactions SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago ID POTENTIAL-ENERGY SURFACE; PRODUCT BRANCHING RATIO; CLASSICAL TRAJECTORY CALCULATIONS; POLYCYCLIC AROMATIC-HYDROCARBONS; TRANSITION-STATE-THEORY; TOTAL RATE-CONSTANT; RAPID COMPRESSION MACHINE; PLUS O-2 REACTIONS; PHENOMENOLOGICAL RATE COEFFICIENTS; ANGULAR-MOMENTUM J-GREATER-THAN-0 AB This review of the role of reaction kinetics in combustion chemistry traces the historical evolution and present state of qualitative and quantitative understanding of a number of reaction systems. Starting from the H(2)-O(2) system, in particular from the reaction between H and O(2), mechanisms and key reactions for soot formation, for the appearance of NO,, and for processes of peroxy radicals in hydrocarbon oxidation are illustrated. The struggle for precise rate constants on the experimental and theoretical side is demonstrated for the example of the reaction H + O(2) -> OH + O. The intrinsic complexity of complex-forming bimolecular reactions, such as observed even in this reaction, also dominates most other key reactions of the systems considered and can be unravelled only with the help of quantum-chemical methods. The multi-channel character of these reactions often also requires the combination with master equation codes. Although kinetics provides an already impressive database for quantitative modelling of simple combustion systems, considerable effort is still required to quantitatively account for the complexities of more complicated fuel oxidation processes. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Gottingen, Inst Phys Chem, D-37077 Gottingen, Germany. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Univ Leeds, Dept Chem, Leeds LS2 9JT, W Yorkshire, England. RP Troe, E (reprint author), Univ Gottingen, Inst Phys Chem, Tammannstr 6, D-37077 Gottingen, Germany. EM shoff@gwdg.de NR 429 TC 254 Z9 260 U1 5 U2 69 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1540-7489 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 43 EP 88 DI 10.1016/j.proci.2004.08.281 PN 1 PG 46 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200007 ER PT J AU Kohse-Hoinghaus, K Barlow, RS Alden, M Wolfrum, E AF Kohse-Hoinghaus, K Barlow, RS Alden, M Wolfrum, E TI Combustion at the focus: laser diagnostics and control SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago ID IN-SITU DETECTION; CAVITY RINGDOWN SPECTROSCOPY; TURBULENT PREMIXED FLAMES; HIGH-PRESSURE FLAMES; JET DIFFUSION FLAME; WAVELENGTH-MODULATION SPECTROSCOPY; POLYCYCLIC AROMATIC-HYDROCARBONS; INDUCED-FLUORESCENCE DETECTION; PARTICLE IMAGE VELOCIMETRY; LOW-TEMPERATURE COMBUSTION AB Fifty years after the foundation of the Combustion Institute and almost 150 years after Michael Faraday's famous lectures on the combustion of a candle, combustion diagnostics have come a long way from visual inspection of a flame to detailed analysis of a combustion process with a multitude of sophisticated techniques, often using lasers. The extended knowledge on combustion phenomena gained by application of these diagnostic techniques, combined with equally advanced numerical simulation of the process, has been instrumental in designing modern combustion devices with efficient performance and reduced pollutant emission. Also, similar diagnostic techniques are now employed to develop sensors for process control in combustion. This article intends to give a perspective on the potential of combustion diagnostics by highlighting selected application examples and by guiding the reader to recent literature. In particular, techniques are emphasized, which permit measurement of important features of the chemical composition, sometimes in conjunction with flow field parameters. Although a complete image of present research and applications in combustion diagnostics and control is beyond the scope of this article, this overview may be a starting place where ideas may be found to solve specific combustion problems with the aid of diagnostics. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Bielefeld, Phys Chem 1, D-33615 Bielefeld, Germany. Sandia Natl Labs, Livermore, CA 94551 USA. Lund Inst Technol, Dept Combust Phys, S-22100 Lund, Sweden. Univ Heidelberg, Inst Phys Chem, D-69120 Heidelberg, Germany. RP Kohse-Hoinghaus, K (reprint author), Univ Bielefeld, Phys Chem 1, Univ Str 25, D-33615 Bielefeld, Germany. EM kkh@pcl.chemie.uni-bielefeld.de RI Kohse-Hoinghaus, Katharina/A-3867-2012 NR 310 TC 125 Z9 132 U1 5 U2 55 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 89 EP 123 DI 10.1016/j.proci.2004.08.274 PN 1 PG 35 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200008 ER PT J AU Westbrook, CK Mizobuchi, Y Poinsot, TJ Smith, PJ Warnatz, E AF Westbrook, CK Mizobuchi, Y Poinsot, TJ Smith, PJ Warnatz, E TI Computational combustion SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago ID PREMIXED TURBULENT COMBUSTION; DIRECT NUMERICAL-SIMULATION; HIGH-TEMPERATURE OXIDATION; FLAME-WALL INTERACTION; HETEROGENEOUS PROPELLANT COMBUSTION; CONDITIONAL MOMENT CLOSURE; CHEMICAL-VAPOR-DEPOSITION; SHOCK-TUBE IGNITION; METHANE-AIR FLAMES; REACTION-MECHANISM AB Progress in the field of computational combustion over the past 50 years is reviewed. Particular attention is given to those classes of models that are common to most system modeling efforts, including fluid dynamics, chemical kinetics, liquid sprays, and turbulent flame models. The developments in combustion modeling are placed into the time-dependent context of the accompanying exponential growth in computer capabilities and Moore's law. Superimposed on this steady growth, the occasional sudden advances in modeling capabilities are identified, and their impacts are discussed. Integration of submodels into system models for spark ignition, diesel and homogeneous charge, compression ignition engines, surface and catalytic combustion, pulse combustion, and detonations are described. Finally, the current state of combustion modeling is illustrated by descriptions of a very large jet lifted 3D turbulent hydrogen flame with direct numerical simulation and 3D large eddy simulations of practical gas burner combustion devices. Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. Japan Aerosp Explorat Agcy, Ctr Informat Technol, Tokyo 1828522, Japan. Inst Natl Polytech Toulouse, ENSEEIHT, Inst Mecan Fluides, UMR,CNRS,INP UPS 5502, F-31400 Toulouse, France. Univ Utah, Dept Chem & Fuels Engn, Salt Lake City, UT 84112 USA. Heidelberg Univ, IWR, D-69120 Heidelberg, Germany. RP Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. EM westbrook1@llnl.gov NR 246 TC 107 Z9 117 U1 8 U2 52 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1540-7489 EI 1873-2704 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 125 EP 157 DI 10.1016/j.proci.2004.08.275 PN 1 PG 33 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200009 ER PT J AU Frouzakis, CE Tomboulides, AG Papas, P Fischer, PF Rais, RM Monkewitz, PA Boulouchos, K AF Frouzakis, CE Tomboulides, AG Papas, P Fischer, PF Rais, RM Monkewitz, PA Boulouchos, K TI Three-dimensional numerical simulations of cellular jet diffusion flames SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE cellular flame; diffusion flame instability ID THERMAL INSTABILITY; EXTINCTION AB Recent experimental investigations have demonstrated that the appearance of particular cellular states in circular non-premixed jet flames significantly depends on a number of parameters, including the initial mixture strength, reactant Lewis numbers, and proximity to the extinction limit (Damkohler number). For CO2-diluted H-2/O-2 jet diffusion flames, these studies have shown that a variety of different cellular patterns or states can form. For given fuel and oxidizer compositions, several preferred states were found to co-exist, and the particular state realized was determined by the initial conditions. To elucidate the dynamics of cellular instabilities, circular non-premixed jet flames are modeled with a combination of three-dimensional numerical simulation and linear stability analysis (LSA), In both formulations, chemistry is described by a single-step, finite-rate reaction, and different reactant Lewis numbers and molecular weights are specified. The three-dimensional numerical simulations show that different cellular flames can be obtained close to extinction and that different states co-exist for the same parameter values. Similar to the experiments, the behavior of the cell structures is sensitive to (numerical) noise. During the transient blow-off process, the flame undergoes transitions to structures with different number of cells, while the flame edge close to the nozzle oscillates in the streamwise direction. For conditions similar to the experiments discussed, the LSA results reveal various cellular instabilities, typically with azimuthal wavenumber m = 1-6. Consistent with previous theoretical work, the propensity for the cellular instabilities is shown to increase with decreasing reactant Lewis number and Damkohler number. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 ETH, Swiss Fed Inst Technol, Aerothermochem & Combust Syst Lab, CH-8092 Zurich, Switzerland. Aristotle Univ Thessaloniki, GR-54006 Thessaloniki, Greece. Colorado Sch Mines, Div Engn, Golden, CO 80401 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Swiss Fed Inst Technol, Fluid Mech Lab, CH-1015 Lausanne, Switzerland. RP Frouzakis, CE (reprint author), ETH, Swiss Fed Inst Technol, Aerothermochem & Combust Syst Lab, CH-8092 Zurich, Switzerland. EM frouzakis@lav.mavt.ethz.ch NR 22 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1540-7489 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 185 EP 192 DI 10.1016/j.proci.2004.08.087 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200013 ER PT J AU Vagelopoulos, CM Frank, JH AF Vagelopoulos, CM Frank, JH TI An experimental and numerical study on the adequacy of CH as a flame marker in premixed methane flames SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE laminar-experiments; heat-release rate; flame-vortex interaction ID AIR FLAMES; FLUORESCENCE; OBSERVABLES; CHEMISTRY AB The CH radical is frequently used as a flame marker because it is relatively short-lived and is present over a narrow region in flames. Discontinuities in the CH field are thus often interpreted as localized extinction of the flame. Recently, however, the adequacy of CH laser-induced fluorescence (LIF) as a flame marker was questioned by an experimental study of flame-vortex interactions in highly N-2-diluted premixed methane flames. We demonstrate both experimentally and numerically that anomalies in the transient response of CH in this earlier study were due to reactant composition variations in the vortex. In addition, we evaluate the adequacy of CH LIF as a flame marker over a much broader range of conditions. Previous numerical studies showed that heat release rate correlates reasonably well with peak [HCO] and the concentration product [OH][CH2O], but poorly with [CH], in highly N-2-diluted premixed methane flames. Here, the correlation between heat release rate and CH is investigated both experimentally, by performing simultaneous measurements of CH, OH, and CH2O LIF, and numerically. We consider undiluted and N-2-diluted premixed methane flames over a range of strain rates and stoichiometries. Results are reported for flames subjected to unsteady stretch and reactant composition variations. For all N-2-dilution levels considered, the peak CH LIF signal correlates poorly with heat release rate when the stoichiometry of the reactant mixture changes from rich to lean. However, when flames are subjected to stretch, the correlation between CH and heat release rate improves as the N2-dilution level decreases. The correlation is reasonably good for undiluted flames with equivalence ratios of 0.8 < phi < 1.2. This result is particularly encouraging, given the relevance of undiluted flames to practical applications, and it motivates further investigation of the parameter space for which difficulties may exist in using CH as a flame marker. (c) 2004 Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Vagelopoulos, CM (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM cmvagel@ca.sandia.gov NR 18 TC 20 Z9 22 U1 0 U2 6 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 241 EP 249 DI 10.1016/j.proci.2004.08.243 PN 1 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200020 ER PT J AU Amantini, G Frank, JH Gomez, A AF Amantini, G Frank, JH Gomez, A TI Experiments on standing and traveling edge flames around flame holes SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE edge flame; counterflow diffusion flames; vortex flame interaction; flame hole ID TRIPLE FLAME; MIXING LAYERS; PROPAGATION; COUNTERFLOW; DYNAMICS; STRAIN AB The behavior of edge flames surrounding an axisymmetric "hole" in CH(4)/O(2)/N(2) laminar counterflow diffusion flames is experimentally studied with appropriate spatial and temporal resolutions, using a combination of CO PLIF, OH PLIF, CO + OH reaction-rate imaging, and PIV. The experimental approach is able to capture the standing edge flame structure, identifying the trailing diffusion flame and lean premixed flame unequivocally, and the rich premixed flame less conclusively. By perturbing a steadily burning flame locally with two counter-propagating toroidal vortices injected simultaneously from opposite sides of the flame, a transient behavior is observed in detail. It encompasses the complete phenomenology from the onset of local extinction on the centerline to the opening of a "hole" in the flame and its eventual healing. Even in the extinction mode, which is the inevitable regime at the beginning of a sufficiently disruptive flame/vortex interaction, the edge flame does not exhibit a negative propagation velocity but appears to be initially advected by the mean radial flow. It then rapidly undergoes a transition from the extinction mode to the ignition mode, developing a positive propagation velocity with respect to the unburned mixture, but with values lower than the planar premixed flame speed corresponding to the composition of the mixture in the mixing layer. The propagation velocity eventually reaches a value of the order of the planar premixed flame speed and maintains such a value during the rest of the interaction, until the extinction "hole" is fully healed. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Yale Univ, Ctr Combust Studies, Dept Engn Mech, New Haven, CT 06520 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Gomez, A (reprint author), Yale Univ, Ctr Combust Studies, Dept Engn Mech, POB 208286, New Haven, CT 06520 USA. EM alessandro.gomez@yale.edu NR 16 TC 22 Z9 22 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1540-7489 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 313 EP 321 DI 10.1016/j.proci.2004.08.230 PN 1 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200028 ER PT J AU Seiser, R Frank, JH Liu, S Chen, JH Sigurdsson, RJ Sesbadri, K AF Seiser, R Frank, JH Liu, S Chen, JH Sigurdsson, RJ Sesbadri, K TI Ignition of hydrogen in unsteady nonpremixed flows SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE transient; unsteady; strain; ignition; hydrogen ID PREMIXED TURBULENT COMBUSTION; RAPID COMPRESSION MACHINE; SCALAR DISSIPATION RATE; N-HEPTANE; DIFFUSION FLAMES; AIR MIXTURES; HEATED AIR; AUTOIGNITION; COUNTERFLOW; STRAIN AB The effects of unsteady strain on hydrogen (H-2) ignition in nonpremixed flows are investigated with both experimental measurements and numerical computations. A mixing layer is established in a counter-flow configuration with a fuel stream containing N-2-diluted H-2 (X-H2 = 0.08) flowing against heated air. A reproducible ignition process is initiated by introducing atomic oxygen into the mixing layer with a pulsed ArF excimer laser, which photodissociates heated O-2 from the oxidizer stream. The temporal evolution of OH during ignition is measured by planar laser-induced fluorescence. Following the induction phase, the measured OH mole fraction increases rapidly to a super-equilibrium value that is 60% greater than the OH mole fraction in a steady diffusion flame. The peak OH mole fraction occurs at approximately 6 ms after the excimer laser pulse. To study the OH time history under transient strain, the fuel stream is pulsed at a fixed time after the initiation of ignition. The response of the ignition kernel is extremely sensitive to the time delay of the flow transient. The unsteady strain can delay the ignition time or extinguish the kernel. Comparisons between computations and experiments are made for the evolution of OH during autoignition both for steady and unsteady strain. For both steady and unsteady strain, the transient one-dimensional counterflow computations show excellent agreement with the experiment in terms of predicting ignition delays and the rate of OH accumulation during the induction period. The computations also capture the super-equilibrium OH during the transition to the formation of a steady flame, although not to the degree observed experimentally. The computations are further used to understand the influence of unsteady strain on the kernel evolution. It is found that the degree of super-equilibrium OH is sensitive to strain transients applied close to the time of thermal runaway. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Seiser, R (reprint author), Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. EM rseiser@ucsd.edu NR 34 TC 7 Z9 7 U1 0 U2 3 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 423 EP 430 DI 10.1016/j.proci.2004.08.254 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200041 ER PT J AU Hawkes, ER Chen, JH AF Hawkes, ER Chen, JH TI Evaluation of models for flame stretch due to curvature in the thin reaction zones regime SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE turbulent-combustion; thin-reaction zones regime; flame stretch; direct numerical simulation ID PREMIXED TURBULENT COMBUSTION; DIRECT NUMERICAL-SIMULATION; LARGE-EDDY SIMULATION; BURNING VELOCITY; AIR FLAMES; SURFACES; FLOWS AB Direct numerical simulation (DNS) was used to study modelling assumptions for the curvature-propagation component of flame stretch in the thin reaction zones regime of turbulent premixed combustion, a regime in which small eddies can penetrate the preheat zone but not the thinner fuel breakdown zone. Simulations of lean hydrogen-air and methane-air flames were conducted, and statistics of flame stretch due to curvature, henceforth referred to simply as stretch, were extracted from a species mass fraction iso-surface taken to represent the flame. The study focussed on investigating the modelling assumptions of Peters [J. Fluid Mech. 384 (1999) 107]. It was found that the mean stretch is dominated by stretch due to correlations of flame speed with curvature, and specifically the effects of tangential diffusion. The modelling suggestions of Peters were found to provide an improvement over the assumptions of a constant flame speed or a flame speed governed by the linear relationship with stretch at small and steady stretch. However for the conditions considered here, diffusive-thermal effects remain well into the thin reaction zones regime, and the suggestions of Peters generally over-predict the mean compressive stretch. An effective diffusivity for flame stretch was suggested and evaluated for the methane simulations. It was found that the effective diffusivity was comparable to the mass diffusivity for flames with a high ratio of flame time to eddy turnover time. The length scales contributing to stretch were investigated, and it was found that while most flame area has a radius of curvature greater than the laminar flame thickness, most stretch occurs in more tightly curved flame elements. Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Hawkes, ER (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM erhawke@ca.sandia.gov RI Hawkes, Evatt/C-5307-2012 OI Hawkes, Evatt/0000-0003-0539-7951 NR 28 TC 36 Z9 36 U1 0 U2 2 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 647 EP 655 DI 10.1016/j.proci.2004.08.106 PN 1 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200066 ER PT J AU Karpetis, AN Barlow, RS AF Karpetis, AN Barlow, RS TI Measurements of flame orientation and scalar dissipation in turbulent partially premixed methane flames SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE scalar dissipation; flame imaging; partially premixed flames; flame orientation; turbulence ID HYDROGEN DIFFUSION FLAMES; COMBUSTION AB Three turbulent flames were studied using a new experimental facility developed at Sandia National Laboratories. Line imaging of Raman and Rayleigh scattering and CO laser-induced fluorescence (LIF) yielded information on all major species, temperature, mixture fraction, and a ID surrogate measure of scalar dissipation. Simultaneously, crossed planar OH LIF imaging provided information on the instantaneous flame orientation, allowing estimation of the full 3D (flame-normal) scalar dissipation rate. The three flames studied were methane-air piloted jet flames (Sandia flames C, D, and E), which cover a range in Reynolds number from 13,400 to 33,600. The statistics of the instantaneous flame orientation are examined in the different flames, with the purpose of studying the prevailing kinematics of isoscalar contours. The 1D and 3D results for scalar dissipation rate are examined in detail, both in the form of conditional averages and in the form of probability density functions. The effect of overall strain and Reynolds number on flame suppression and eventual extinction is also investigated, by examining the doubly conditional statistics of temperature in the form of S-shaped curves. This latter analysis reveals that double conditioning of temperature on both mixture fraction and scalar dissipation does not collapse the data from these flames onto the same curve at low scalar dissipation rates, as might be expected from simple flamelet concepts. (c) 2004 Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Karpetis, AN (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. EM ankarpe@sandia.gov; barlow@ca.sandia.gov NR 17 TC 65 Z9 65 U1 2 U2 13 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 665 EP 672 DI 10.1016/j.proci.2004.08.222 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200068 ER PT J AU Barlow, RS Karpetis, AN AF Barlow, RS Karpetis, AN TI Scalar length scales and spatial averaging effects in turbulent piloted methane/air jet flames SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE turbulent flames; scalar variance; scalar dissipation; length scales; Raman scattering ID DIFFUSION FLAMES; RAMAN-SCATTERING; MIXTURE-FRACTION; DISSIPATION; HYDROGEN; COMBUSTION; SHUTTER AB The effects of spatial averaging in measurements of scalar variance and scalar dissipation in three piloted methane/air jet flames (Sandia flames C, D, and E) are investigated. Line imaging of Raman scattering, Rayleigh scattering, and laser-induced CO fluorescence is applied to obtain simultaneous single-shot measurements of temperature, the mass fractions of all major species, and mixture fraction, xi, along 7-mm segments. Spatial filters are applied to ensembles of instantaneous profiles to quantify effects of spatial averaging on the Favre mean and variance of mixture fraction and scalar dissipation at several locations in the three flames. The radial contribution to scalar dissipation, chi(r) = 2D xi(partial derivative xi/partial derivative r)(2), is calculated from the filtered instantaneous profiles. The variance of mixture fraction tends to decrease linearly with increasing filter width, while the mean and variance of scalar dissipation are observed to follow an exponential dependence. In each case, the observed functional dependence is used to extrapolate to zero filter width, yielding estimates of the "fully resolved" profiles of measured quantities. Length scales for resolution of scalar variance and scalar dissipation are also extracted from the spatial filtering analysis and compared with length scales obtained from spatial autocorrelations. These results provide new insights on the small scale structure of turbulent jet flames and on the spatial resolution requirements for measurements of scalar variance and scalar dissipation. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Barlow, RS (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. EM barlow@ca.sandia.gov NR 21 TC 29 Z9 29 U1 0 U2 7 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 673 EP 680 DI 10.1016/j.proci.2004.08.139 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200069 ER PT J AU Lachaux, T Halter, F Chauveau, C Gokalp, I Shepherd, IG AF Lachaux, T Halter, F Chauveau, C Gokalp, I Shepherd, IG TI Flame front analysis of high-pressure turbulent lean premixed methane-air flames SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE turbulent; pressure; premixed; scale; wrinkled ID COMBUSTION; MIXTURES AB An experimental study on lean turbulent premixed methane-air flames at high pressure is conducted by using a turbulent Bunsen flame configuration. A single equivalence ratio flame at (phi = 0.6 is explored for pressures ranging from atmospheric pressure to 0.9 MPa. LDA measurements of the cold flow indicate that turbulence intensities and the integral length scale are not sensitive to pressure. Due to the decreased kinematic viscosity with increasing pressure, the turbulent Reynolds numbers increase, and isotropic turbulence scaling relations indicate a large decrease of the smallest turbulence scales. Available experimental results and PREMIX code computations indicate a decrease in laminar flame propagation velocities with increasing pressure, essentially between the atmospheric pressure and 0.5 MPa. The U'/S-L ratio increases therefore accordingly. Instantaneous flame images are obtained by Mie scattering tomography. The images and their analysis show that pressure increase generates small scale flame structures. In an attempt to generalize these results, the variance of the flamelet curvatures, the standard deviation of the flamelet orientation angle, and the flamelet crossing lengths have been plotted against Re-t(1/2) which is proportional to the ratio between the integral and Taylor length scales, and which increases with pressure. These three parameters vary linearly with the ratio between large and small turbulence scales and clearly indicate the strong effect of this parameter on premixed turbulent flame dynamics and structure. An obvious consequence is the increase in flame surface density and hence burning rate with pressure, as confirmed by its direct determination from 2D tomographic images. (c) 2004 Published by Elsevier Inc. on behalf of The Combustion Institute. C1 CNRS, Lab Combust & Syst Reactifs, F-45071 Orleans, France. Lawrence Berkeley Natl Lab, Adv Energy Technol Dept, Berkeley, CA 94720 USA. RP Gokalp, I (reprint author), CNRS, Lab Combust & Syst Reactifs, F-45071 Orleans, France. EM gokalp@cnrs-orleans.fr NR 18 TC 33 Z9 33 U1 1 U2 7 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 819 EP 826 DI 10.1016/j.proci.2004.08.191 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200086 ER PT J AU Sankaran, R Im, HG Hawkes, ER Chen, JH AF Sankaran, R Im, HG Hawkes, ER Chen, JH TI The effects of non-uniform temperature distribution on the ignition of a lean homogeneous hydrogen-air mixture SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE ignition; HCCI; non-uniform temperature; reaction front; DNS AB To characterize the ignition process in homogeneous charge compression ignition engines, high fidelity simulations are performed to study the effects of different initial temperature distributions on the autoignition of a turbulent homogeneous mixture at high pressure. The effects of the initial temperature distribution on the ignition and subsequent heat release are studied by comparison of simulations with three initial random temperature fields having different skewness. It is found that the scalar mixing and turbulence have a significant influence on the initial location and further evolution of the ignition kernels. A comparison of the integrated heat release rates shows that the presence of a hot core leads to early ignition and increased duration of burning, while a cold core leads to a dormant end gas, which is consumed by slow combustion. The extent of flame fronts is quantified by a temperature gradient cut-off, revealing distinct behavior in the appearance of flame fronts for the three cases. Finally, two distinct ignition regimes, namely the spontaneous propagation and the deflagration regimes, are identified, and a predictive criterion is defined based on the spontaneous propagation speed and deflagration speed at the local mixture conditions. The predictions are found to be consistent with the observed results, suggesting a potential strategy in the modeling of HCCI combustion process. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Michigan, Dept Mech Engn, Ann Arbor, MI 48109 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Im, HG (reprint author), Univ Michigan, Dept Mech Engn, 2250 GG Brown Bldg,2350 Hayward St, Ann Arbor, MI 48109 USA. EM hgim@umich.edu RI Im, Hong/J-4317-2012; Sankaran, Ramanan/D-9254-2015; Hawkes, Evatt/C-5307-2012 OI Sankaran, Ramanan/0000-0002-5352-9915; Hawkes, Evatt/0000-0003-0539-7951 NR 17 TC 66 Z9 67 U1 0 U2 11 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 875 EP 882 DI 10.1016/j.proci.2004.08.176 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200093 ER PT J AU Senosiain, JP Klippenstein, SJ Miller, JA AF Senosiain, JP Klippenstein, SJ Miller, JA TI A complete statistical analysis of the reaction between OH and CO SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago ID POTENTIAL-ENERGY SURFACE; PHENOMENOLOGICAL RATE COEFFICIENTS; WELL MASTER EQUATION; PRESSURE-DEPENDENCE; RATE CONSTANTS; PLUS CO; KINETICS; TEMPERATURE; RADICALS; EXCHANGE AB The current investigation is an attempt to provide as complete a statistical-theoretical treatment of the title reaction as possible. We have improved the detail of the calculations of Senosiain et al. [Jnt. J. Chem. Kinet. 35 (9) (2003) 4641 and investigated the impact of variational effects and angular momentum conservation on the overall thermal rate constants. Although the magnitude of these effects is not large, they produce different (adjusted) vibrationally adiabatic reaction barriers and energy transfer parameters. More importantly, they result in nearly temperature-independent rate coefficients below 500 K, in good agreement with low temperature experiments. Reaction barriers obtained by fitting experimental data in a broad temperature and pressure range are in excellent agreement with high level electronic structure calculations (well within 1 kcal/mol). (c) 2004 Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Senosiain, JP (reprint author), Sandia Natl Labs, Combust Res Facil, POB 969,MS 9055, Livermore, CA 94551 USA. EM jpsenos@sandia.gov OI Klippenstein, Stephen/0000-0001-6297-9187 NR 32 TC 33 Z9 33 U1 0 U2 12 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 945 EP 953 DI 10.1016/j.proci.2004.07.009 PN 1 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200101 ER PT J AU Michael, JV Su, MC Sutherland, JW Harding, LB Wagner, AF AF Michael, JV Su, MC Sutherland, JW Harding, LB Wagner, AF TI Rate constants for D+C2H4 -> C2H3D+H at high temperature: implications to the high pressure rate constant for H+C2H4 -> C2H5 SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE rate constants; shock tube; RRKM theory; high-pressure limit; isotopic ratio ID CORRELATED MOLECULAR CALCULATIONS; DENSITY-FUNCTIONAL THEORY; REVERSE RATE CONSTANTS; SHOCK-TUBE TECHNIQUE; GAUSSIAN-BASIS SETS; TRANSITION-STATE; WAVE-FUNCTIONS; HYDROGEN-ATOM; AB-INITIO; PHOTOLYSIS AB The shock tube technique with H- and D-atom atomic resonance absorption spectrometry detection has been used to study the reaction, D + C2H4 -> C2H3D + H over the temperature range, 1153-1616 K. The rate constants for this reaction were found to be temperature dependent with k = (2.56 +/- 0.46) x 10(-10) exp (-2797 +/- 239K/ T) cm(3) molecule(-1) S-1 with the errors being at the one standard deviation level. The present data have been combined with earlier lower temperature determinations, and the joint database has been examined with theory that includes both an ab initio determination of the potential energy surface and an evaluation of the rate constants using the RRKM 'theory. Similar calculations have been made for the analogous all-H reaction. For both isotopic combinations, the agreement between theory and experiment is good, allowing a new estimate from theory for the high-pressure limit for H + C2H4 -> C2H5 of 0.420 x 10(-15) T-1.75 exp(-604.9 K/T) cm(3) molecule(-1) s(-1) for 200-2000 K. Since the D + C2H4 measurements reported here are the only high temperature measurements for either isotopic combination, the new high-pressure limiting estimate should be the best available at high temperatures. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Michael, JV (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM jmichael@anl.gov RI Michael, Joe/E-3907-2010 NR 38 TC 17 Z9 17 U1 3 U2 11 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 965 EP 973 DI 10.1016/j.proci.2004.08.013 PN 1 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200103 ER PT J AU Harding, LB Klippenstein, SJ Georgievskii, Y AF Harding, LB Klippenstein, SJ Georgievskii, Y TI Reactions of oxygen atoms with hydrocarbon radicals: a priori kinetic predictions for the CH3+O, C2H5+O, and C2H3+O reactions SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE kinetics; theory; CH3+O; C2H5+O; C2H3+O ID CORRELATED MOLECULAR CALCULATIONS; TRANSITION-STATE THEORY; GAUSSIAN-BASIS SETS; METHYL RADICALS; REACTION COORDINATE; RATE-CONSTANT; O(P-3) ATOMS; PRODUCT; NO; DECOMPOSITION AB The reactions of oxygen atoms with methyl, ethyl, and vinyl radicals are studied with a combination of ab initio quantum chemistry, variational transition state theory, and classical trajectory simulations. The interaction between the two radicals is examined with multi-reference configuration-interaction calculations employing augmented double zeta and augmented triple zeta basis sets. The implementation of analytic representations of the ab initio data within variable-reaction -coordinate (VRC) transition state theory (TST) yields predictions for the high-pressure limit addition rate coefficients. The dynamically corrected theoretical predictions for the CH3 + O, C2H5 + O, and C2H3 + O high-pressure rate coefficients are well reproduced by the expressions 9.20 x 10(-11) T-0.050 exp(136/RT), 5.26x 10(-11)T(0.032) exp 394/RT), and 1.71 x 10(-11)T(0.205) exp (427/RT) cm(3) molecule(-1) s(-1), respectively, where R = 1.987 cal mol(-1) K-1, for temperatures between 200 and 2500 K. For the CH3 + O reaction, these predictions are in remarkably good agreement with the extensive experimental data, while for the C2H5 + O and C2H3 + O reactions the theoretical predictions appear somewhat lower and higher, respectively, than the rather limited experimental data. VRC-TST analyses also suggest that the abstraction reactions to produce C2H4 + OH and C2H2 + OH have rate coefficients that are about 10% of the corresponding addition rate. Notably, the latter predictions have a significantly greater uncertainty, probably about a factor of 2, than do those for the addition. For comparison, the abstraction was experimentally observed to be about 21 +/- 8% of the total for C2H5 + O, but was not observed in C2H3 + O. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Harding, LB (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM harding@anl.gov NR 42 TC 36 Z9 36 U1 1 U2 20 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 985 EP 993 DI 10.1016/j.proci.2004.08.184 PN 1 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200105 ER PT J AU Zheng, XL Lu, TF Law, CK Westbrook, CK Curran, HJ AF Zheng, XL Lu, TF Law, CK Westbrook, CK Curran, HJ TI Experimental and computational study of nonpremixed ignition of dimethyl ether in counterflow SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE dimethyl ether; ignition; reduced mechanism ID DETAILED CHEMISTRY; REACTION-KINETICS; FLOW REACTORS; HEATED AIR; OXIDATION; HYDROGEN AB The ignition temperature of nitrogen-diluted dimethyl ether (DME) by heated air in counterflow was experimentally determined for DME concentration from 5.9% to 30%, system pressure from 1.5 to 3.0 atm, and pressure-weighted strain rate from 110 to 170 s(-1). These experimental data were compared with two mechanisms that were, respectively, available in 1998 and 2003, with the latter being a substantially updated version of the former. The comparison showed that while the 1998-mechanism uniformly over-predicted the ignition temperature, the 2003-mechanism yielded a surprisingly close agreement for all experimental data. Sensitivity analysis for the near-ignition state based on both mechanisms identified the deficiencies of the 1998-mechanism, in particular, the specifics of the low-temperature cool flame chemistry in effecting ignition at higher temperatures, as the fuel stream is being progressively heated from its cold boundary to the high-temperature ignition region around the hot-stream boundary. The 2003-mechanism, consisting of 79 species and 398 elementary reactions, was then systematically simplified by using the directed relation graph method to a skeletal mechanism of 49 species and 251 elementary reactions, which in turn was simplified further by using computational singular perturbation method and quasi-steady-state species assumption to a reduced mechanism consisting of 33 species and 28 lumped reactions. It was demonstrated that both the skeletal and reduced mechanisms mimicked the performance of the detailed mechanism with high accuracy. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Princeton Univ, Dept Mech & Aerosp Engn, Princeton, NJ 08540 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Natl Univ Ireland Univ Coll Galway, Dept Chem, Galway, Ireland. RP Law, CK (reprint author), Princeton Univ, Dept Mech & Aerosp Engn, Princeton, NJ 08540 USA. EM cklaw@princeton.edu RI Law, Chung /E-1206-2013; Zheng, Xiaolin/F-5231-2011; Lu, Tianfeng/D-7455-2014; OI Lu, Tianfeng/0000-0001-7536-1976; Curran, Henry/0000-0002-5124-8562 NR 22 TC 49 Z9 49 U1 4 U2 15 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1101 EP 1109 DI 10.1016/j.procl.2004.08.241 PN 1 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200118 ER PT J AU Glaude, PA Pitz, WJ Thomson, MJ AF Glaude, PA Pitz, WJ Thomson, MJ TI Chemical kinetic modeling of dimethyl carbonate in an opposed-flow diffusion flame SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE dimethyl carbonate; oxygenated fuel; opposed flow flame; chemical kinetic modeling; flame structure ID THERMODYNAMIC PROPERTIES; VIBRATIONAL FREQUENCIES; AB-INITIO; OXIDATION; ETHER; HYDROCARBONS; MECHANISM; BARRIERS AB Dimethyl carbonate (DMC) has been of interest as an oxygenate additive to diesel fuel because of its high oxygen content. In this study, a chemical kinetic mechanism for DMC was developed for the first time and used to understand its combustion under conditions in an opposed flow diffusion flame. Computed results were compared to previously published experimental results from an opposed flow diffusion flame. It was found that the decomposition rate DMC double right arrow H3COC(=O)O-center dot + CH3 in the flame was much slower than originally thought because resonance stabilization in the H3COC(=O)O-center dot radical was less than expected. Also, a new molecular elimination path for DMC is proposed, and its rate is calculated by quantum chemical methods. In the simulations of DMC in the flame, it was determined that much of the oxygen in dimethyl carbonate goes directly to CO2. This characteristic reduces the effectiveness of DMC for soot reduction in diesel engines. In an ideal oxygenate additive for diesel fuel, each oxygen atom stays bonded to one carbon atom in the products thereby preventing the formation of carbon-carbon bonds that can lead to soot. When CO2 is formed directly, two oxygen atoms are bonded to one carbon atom thereby wasting one oxygen atom in the oxygenate additive. To determine how much CO2 is formed directly, the branching ratio of the key reaction, CH3OCcenter dot=O going to the products CH3 + CO2 or CH3O + CO, was determined by ab initio methods. The A-factors of the rate constant of this reaction were found to be about 10-20 times higher than previous estimates. The new reaction rate constants obtained can be used as reaction rate rules for all oxygenates that contain the ester moiety including biodiesel. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. CNRS, Dept Chim Phys React, F-75700 Paris, France. Univ Toronto, Dept Mech & Ind Engn, Toronto, ON, Canada. RP Pitz, WJ (reprint author), Lawrence Livermore Natl Lab, POB 5508, Livermore, CA 94550 USA. EM pitz1@llnl.gov OI Glaude, Pierre-Alexandre/0000-0001-9166-8388 NR 30 TC 62 Z9 64 U1 7 U2 33 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1111 EP 1118 DI 10.1016/j.proci.2004.08.096 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200119 ER PT J AU Kiefer, JH Santhanam, S Srinivasan, NK Tranter, RS Klippenstein, SJ Oehlschlaeger, MA AF Kiefer, JH Santhanam, S Srinivasan, NK Tranter, RS Klippenstein, SJ Oehlschlaeger, MA TI Dissociation, relaxation and incubation in the high-temperature pyrolysis RRKM of ethane, and a successful modeling SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE ethane; dissociation; relaxation; chain-mechanism; RRKM ID THERMAL UNIMOLECULAR REACTIONS; 2-DIMENSIONAL MASTER EQUATION; TRANSITION-STATE THEORY; VIBRATIONAL-RELAXATION; RATE CONSTANTS; LOW-PRESSURES; COMBUSTION; DECOMPOSITION; NEOPENTANE; KINETICS AB The thermal dissociation of ethane has been examined in two complementary sets of shock-tube experiments that together cover 1400-2200 K and a pressure range of 70-5700 torr. These experiments used both laser-schlieren and UV absorption of CH3 as diagnostics. In addition, that ethane exhibits a double vibrational relaxation has been confirmed for high temperatures, demonstrating slow IVR in this molecule, and both relaxation times have been determined for 1000-1500 K. Some estimates of dissociation incubation times were possible over about 1900-2100 K. An RRKM model calculation using the earlier Klippenstein-Harding theoretical model provides a remarkably accurate description of the complete range of data with down = 120 (T/300)(0.9) cm(-1). Over 1400-2200 K, the k(infinity) from this model is 8.03 X 10(28) T-3.52 exp(-95346 cal/mol/RT) s(-1). It is suggested that the success of this model shows that there is no non-RRKM behavior in this reaction. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Illinois, Dept Chem Engn, Chicago, IL 60607 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Stanford Univ, Dept Mech Engn, Stanford, CA 94305 USA. RP Kiefer, JH (reprint author), Univ Illinois, Dept Chem Engn, Chicago, IL 60607 USA. EM kiefer@uic.edu RI Oehlschlaeger, Matthew/C-5745-2009 OI Oehlschlaeger, Matthew/0000-0003-3174-9615 NR 31 TC 53 Z9 53 U1 0 U2 15 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1129 EP 1135 DI 10.1016/j.proci.2004.08.215 PN 1 PG 7 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200121 ER PT J AU Grcar, JF Glarborg, P Bell, JB Day, MS Loren, A Jensen, AD AF Grcar, JF Glarborg, P Bell, JB Day, MS Loren, A Jensen, AD TI Effects of mixing on ammonia oxidation in combustion environments at intermediate temperatures SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE ammonia chemistry; fuel nitrogen; mixing ID NITRIC-OXIDE; FLOW REACTOR; REDUCTION; CHEMISTRY; FLAMES; CONVERSION; SYSTEMS AB Ammonia often occurs in combustion gases as a product of fuel-nitrogen. Since either NO or N-2 may predominate as the product of ammonia oxidation, there is considerable interest in understanding the factors responsible for selecting the final products. In flames, the selectivity is known to depend on whether the reaction zones are premixed or nonpremixed. This paper reports on a combined experimental and modeling investigation of ammonia chemistry in a hot combustion environment that is below flame temperatures, such as in post-combustion gases. Experiments that mix highly diluted ammonia-methane and oxygen-water streams are interpreted in terms of a plug-flow model, a simplified mixing reactor model, and a two-dimensional direct numerical simulation. The study finds that the final products of ammonia oxidation remain sensitive to mixing even at temperatures below those of self-sustaining flames. At low temperatures, ammonia oxidation occurs in a premixed reaction zone, but at sufficiently high temperatures a nonpremixed reaction zone may develop that produces significantly less NO than the equivalent premixed system. A direct numerical simulation is required to predict the behavior over the full range of conditions investigated experimentally, while a simplified mixing reactor model captures the essential features as long as the radial gradients are not too steep. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Lawrence Berkeley Natl Lab, Ctr Computat Sci & Engn, Berkeley, CA 94720 USA. Tech Univ Denmark, Dept Chem Engn, DK-2800 Lyngby, Denmark. RP Grcar, JF (reprint author), Lawrence Berkeley Natl Lab, Ctr Computat Sci & Engn, Berkeley, CA 94720 USA. EM jfgrcar@lbl.gov NR 25 TC 7 Z9 9 U1 4 U2 9 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1193 EP 1200 DI 10.1016/j.proci.2004.08.018 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200128 ER PT J AU Frenklach, M Schuetz, CA Ping, J AF Frenklach, M Schuetz, CA Ping, J TI Migration mechanism of aromatic-edge growth SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE soot; PAH; surface growth; reaction mechanisms; kinetic Monte Carlo ID UNIMOLECULAR REACTION SYSTEMS; SOOT FORMATION; ELECTRONIC-STRUCTURE; SURFACE GROWTH; MULTIPLE-WELL; SIMULATION; FLAMES; HYDROCARBONS; MOLECULES; CHEMISTRY AB A new reaction pathway is suggested for the five-member ring migration along a graphene edge. The migration sequence is initiated by H atom addition to the adsorbed cyclopenta group. The elementary steps of the migration pathway were analyzed using quantum-chemical calculations. Based on the obtained energetics, the dynamics of the system were investigated by solving the master equations. The reaction rates of the new pathway show values sufficiently high to compete with, and even dominate, other surface reactions. The kinetics results indicate that the rate-limiting step of the migration sequence is the P-scission of the five-member ring after the addition of an H atom, whereas the other steps reach partial equilibrium at higher temperatures. Employing the new migration kinetics along with adsorption, desorption, and growth steps, sterically resolved kinetic Monte Carlo simulations were carried out at conditions typical of soot growth in hydrocarbon flames. The simulation results further support the critical role of five-member ring migration in the growth of graphene layers. The evolving surface morphology and ensuing growth rate are determined by competition between the migration of five-member rings and "nucleation" of six-member rings at surface corners. An important implication of this migration phenomenon is that while five-member rings are constantly being formed on the growing edge, they do not accumulate; rather they are converted to six-member rings. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Calif Berkeley, Dept Engn Mech, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Frenklach, M (reprint author), Univ Calif Berkeley, Dept Engn Mech, Berkeley, CA 94720 USA. EM myf@me.berkeley.edu NR 33 TC 31 Z9 31 U1 0 U2 14 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1389 EP 1396 DI 10.1016/j.proci.2004.07.048 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200150 ER PT J AU Balthasar, M Frenklach, M AF Balthasar, M Frenklach, M TI Monte-Carlo simulation of soot particle coagulation and aggregation: the effect of a realistic size distribution SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE soot formation; particle aggregation; morphology; Monte-Carlo simulations ID LAMINAR PREMIXED FLAMES; LIGHT-SCATTERING; AIR-POLLUTION; COALESCENCE; MORTALITY; AEROSOL; MOMENTS AB The evolution of the morphology of primary soot particles was investigated in a laminar premixed flame with the emphasis on the effect of a realistic particle size distribution. A time-dependent Monte-Carlo method was used to calculate flame trajectories of single particles. In the nucleation zone of the flame, particles were grown by coagulation and simultaneous surface growth. The particles for coagulation were selected according to a pre-calculated size distribution obtained by solving the dynamics of the entire soot particle ensemble. In the post-nucleation zone, defined by the point of transition from coalescent to aggregate growth, only surface growth was applied to the particles. The simulation results provide further support to the notion that particle nucleation and the presence of small particles influence the morphology of primary particles and the location of transition. It is demonstrated that the mean size of subparticles comprising the primary particles is substantially smaller when using a realistic size distribution in the nucleation zone of the investigated flame. This, in turn, reduces the degree of aggregation of the primary particles at the time of transition to an extent that surface growth is able to recover their spherical shape in the post-nucleation zone. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Cambridge, Dept Chem Engn, Cambridge CB2 3RA, England. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Mech Engn, Berkeley, CA 94720 USA. RP Balthasar, M (reprint author), Univ Cambridge, Dept Chem Engn, Pembroke St, Cambridge CB2 3RA, England. EM mb404@cam.ac.uk NR 37 TC 26 Z9 31 U1 2 U2 20 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1467 EP 1475 DI 10.1016/j.proci.2004.07.035 PN 1 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200159 ER PT J AU Shaddix, CR Williams, TC Blevins, LG Schefer, RW AF Shaddix, CR Williams, TC Blevins, LG Schefer, RW TI Flame structure of steady and pulsed sooting inverse jet diffusion flames SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE soot; PAH; diffusion flame; laminar; unsteady ID PARTICLES; DYNAMICS; EXHAUST; METHANE; PLUMES; CO AB In turbulent buoyant fire plumes, local inverse diffusion flames of air injected into gaseous fuel or fuel vapors occur, but little is known about the tendency to form soot and produce thermal radiation in these flame structures. To investigate these phenomena, steady and pulsed normal and inverse jet diffusion flames of methane/air and ethylene/air have been stabilized on a slot burner, which has advantages over a coannular flame geometry for performing flame imaging measurements in sooty flames. OH and PAH laser-induced fluorescence (LIF), soot laser-induced incandescence (LII), and soot thermal emission at 850 nm have been measured in the lower flame region of steady and pulsed flames. These measurements reveal that the relative positions of these different structural features are very similar in the normal and inverse steady flames of each fuel. Also, the OH signals are nearly identical in the normal and inverse flames. The inverse flame PAH signals and soot concentrations are somewhat smaller than for the normal flames, and the near-infrared radiation is approximately 250/0 lower for the inverse flame. When the central slot is pulsed, the primary buoyant vortex roll-up occurs on the fuel-rich side of inverse flames, resulting in strongly enhanced PAH signals and soot concentrations. The near-infrared radiation also increases in the pulsed flames, but not from the soot within the vortex roll-up region. In general, enhancements in peak signals from soot and near-infrared radiation similar to those in pulsed normal diffusion flames are apparent in pulsed inverse diffusion flames. PAH signals are clearly greatest in the pulsed inverse flames. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Shaddix, CR (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. EM crshadd@sandia.gov RI Schefer, Jurg/G-3960-2012 NR 29 TC 31 Z9 31 U1 1 U2 20 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1501 EP 1508 DI 10.1016/j.proci.2004.08.244 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200163 ER PT J AU Frank, JH Settersten, TB AF Frank, JH Settersten, TB TI Two-photon LIF imaging of atomic oxygen in flames with picosecond excitation SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE planar laser-induced fluorescence; imaging diagnostics; two-photon LIF ID LASER-INDUCED FLUORESCENCE; H-ATOM; O-ATOM; GASES AB Interference-free planar laser-induced fluorescence measurements of atomic oxygen are demonstrated in steady and unsteady laminar premixed methane flames. Two-dimensional LIF measurements of atomic oxygen present a challenge because of the relatively weak two-photon absorption cross-sections and the nonlinear dependence of the LIF signal on laser intensity. Previous two-photon LIF measurements of atomic oxygen in hydrocarbon flames using nanosecond laser excitation were complicated by significant interference from photolytically produced oxygen atoms. Recent results from line-imaging studies in our laboratory indicate that CO2 is the dominant photolytic precursor. Here, we use picosecond excitation to image atomic oxygen with negligible photolytic interference. We demonstrate this capability in premixed CH4/O-2/N-2 (phi = 1-08,X-N2 = 0.63) flames with an adiabatic flame temperature of 2480 K and an estimated peak O-atom mole fraction of 0.5%. Peak single-shot signal-to-noise ratios of 9 are achieved, and the estimated detection limit is approximately 80 ppm. Quantitative O-atom LIF measurements also require knowledge of the temperature-dependent quenching cross-sections, which are not currently available. The effects of collisional quenching on the O-atom LIF are predicted using two models for the temperature dependence of quenching cross-sections, and the results indicate that O-atom LIF signals can provide accurate measurements of O-atom profiles in flames. Measurements in an acoustically forced Bunsen flame illustrate the feasibility of using O-atom LIF to investigate flow flame interactions. (c) 2004 Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Frank, JH (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM jhfrank@ca.sandia.gov RI Settersten, Thomas/B-3480-2009 OI Settersten, Thomas/0000-0002-8017-0258 NR 23 TC 16 Z9 16 U1 1 U2 21 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1527 EP 1534 DI 10.1016/j.proci.2004.08.151 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200166 ER PT J AU Cool, TA Nakajima, K Taatjes, CA McIlroy, A Westmoreland, PR Law, ME Morel, A AF Cool, TA Nakajima, K Taatjes, CA McIlroy, A Westmoreland, PR Law, ME Morel, A TI Studies of a fuel-rich propane flame with photoionization mass spectrometry SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE mass spectrometry; photoionization; premixed laminar flame ID OXIDATION; COMBUSTION; CHEMISTRY; KINETICS; MODEL AB Flame-sampling photoionization mass spectrometry, using continuously tunable synchrotron radiation, offers important advantages for studies of flame chemistry. Mole fraction profile measurements for 24 flame species are presented for a fuel-rich low-pressure premixed laminar C3H8/O-2/Ar flame. Near-threshold photoionization efficiency measurements provide selective detection of individual isomers and unambiguous identifications of other flame species of near-equal mass. The absolute molar composition of the allene and propyne isomers Of C3H4 was determined. Absolute cross-sections for photoionization of C2H2, C2H4, CH3OH, C3H4 (propyne), CH3CHO, (CH3)(2)CO, and C6H6 were used to determine molecular beam mass discrimination factors valid for ion masses ranging from 26 to 78 amu. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Univ Massachusetts, Dept Chem Engn, Amherst, MA 01003 USA. RP Cool, TA (reprint author), Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA. EM tac13@cornell.edu NR 25 TC 119 Z9 139 U1 7 U2 36 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1681 EP 1688 DI 10.1016/j.proci.2004.08.103 PN 1 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RW UT WOS:000229944200183 ER PT J AU Lawn, CJ Williams, TC Schefer, RW AF Lawn, CJ Williams, TC Schefer, RW TI The response of turbulent premixed flames to normal acoustic excitation SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE premixed; acoustically excited; burning velocity ID COMBUSTION INSTABILITIES; INTENSE TURBULENCE; DUCTED FLAME; MODEL; STRAIN; BURNER AB To model the thermo-acoustic excitation of flames in practical combustion systems, it is necessary to know how a turbulent flame front responds to an incident acoustic wave. This will depend partly on the way in which the burning velocity responds to the wave. In this investigation, the response of CH4/air and CH4/H-2/air mixtures has been observed in a novel flame stabilisation configuration, in which the premixture of fuel and air is made to decelerate under controlled conditions in a wide-angle diffuser. Control is provided by an annular wall-jet of air and by turbulence generators at the inlet. Ignition from the outlet of the diffuser allows an approximately flat flame to propagate downwards and stabilise at a height that depends on the turbulent burning velocity. When the flow is excited acoustically, the ensemble-averaged height oscillates. The fluctuations in flow velocity and flame height are monitored by phase-locked particle image velocimetry and OH-planar laser induced fluorescence, respectively. The flame stabilised against a lower incident velocity as the acoustic amplitude increased. In addition, at the lowest frequency of 52 Hz, the fluctuations in turbulent burning velocity (as represented by the displacement speed) were out-of-phase with the acoustic velocity. Thus, the rate of displacement of the flame front relative to the flow slowed as the flow accelerated, and so the flame movement was bigger than it would have been if the burning velocity had not responded to the acoustic fluctuation. With an increase in frequency to 119 Hz, the relative flame movement became even larger, although the phase-difference was reduced, so the effect on burning velocity was less dramatic. The addition of hydrogen to the methane, so as to maintain the laminar burning velocity at a lower equivalence ratio, suppressed the response at low amplitude, but at a higher amplitude, the effect was reversed. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ London Queen Mary & Westfield Coll, Dept Engn, London E1 4NS, England. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Lawn, CJ (reprint author), Univ London Queen Mary & Westfield Coll, Dept Engn, Mile End Rd, London E1 4NS, England. EM c.j.lawn@umul.ac.uk RI Schefer, Jurg/G-3960-2012 NR 15 TC 11 Z9 12 U1 0 U2 4 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1749 EP 1756 DI 10.1016/j.proci.2004.07.049 PN 2 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300006 ER PT J AU Short, M Sharpe, GJ Gorchkov, V Bdzil, JB AF Short, M Sharpe, GJ Gorchkov, V Bdzil, JB TI Self-sustaining, weakly curved, imploding pathological detonation SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE detonations; endothermic reactions; self-sustaining ID DIRECT INITIATION; SHOCK DYNAMICS; STABILITY; WAVES; CURVATURE AB We provide the first theoretical demonstration of the existence ofquasi-one-dimensional, quasi-steady, self-sustaining convergent detonation waves. These occur in systems where, in the planar wave, the rate of heat release by chemical reaction reaches a maximum at a point of incomplete reaction. The case examined in the present paper is that for a two-step sequential reaction, with the second stage endothermic. We construct detonation velocity against curvature relationships for converging waves, and compare these theoretical curves with direct numerical simulations of imploding detonations in cylindrical and spherical geometries. We also comment on the one-dimensional stability of imploding and diverging detonation fronts governed by the two-step model. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Illinois, Dept Theoret & Appl Mech, Urbana, IL 61801 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Short, M (reprint author), Univ Illinois, Dept Theoret & Appl Mech, Urbana, IL 61801 USA. EM short1@uiuc.edu NR 31 TC 1 Z9 1 U1 1 U2 5 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 1899 EP 1906 DI 10.1016/j.proci.2004.07.051 PN 2 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300022 ER PT J AU Telengator, AM Margolis, SB Williams, FA AF Telengator, AM Margolis, SB Williams, FA TI Influence of distributed solid-phase reactions on deflagrations in confined porous propellants SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago ID BOUNDARY-VALUE-PROBLEMS; ITERATED DEFERRED CORRECTIONS; ENERGETIC MATERIALS; 2-PHASE FLOW; NUMERICAL-INTEGRATION; IMPLEMENTATION; EIGENVALUE; COMBUSTION; FORMULAS; MODEL AB Combustion processes in energetic materials are often modeled by a surface gasification reaction followed by a distributed gaseous flame. However, under confinement, deflagrations in porous or granular propellants are generally accompanied by an increasing pressure difference, or overpressure, between the burned-gas region and the unburned reactants deep within the pores of the material. As the overpressure and/or the solid-phase reaction rate become sufficiently large, the gaseous and solid reaction zones tend to merge into a single multiphase reaction region. Furthermore, in certain parameter regimes, the gas flame penetrates into the porous solid, resulting in subsurface gaseous combustion. When the activation energies of the gaseous and solid-phase reactions are of the same order of magnitude and/or the overpressure becomes significant, gasification reactions may also become active within the solid, thus eliminating a distinct propellant surface and forming a distributed multiphase reaction layer. A large activation-energy analysis of this scenario is presented to study the effects of distributed solid reactions on the deflagration structure and the burning-rate response. The burning-rate eigenvalue is obtained from a numerical solution of the reaction-zone problem, and the results are calculated for various overpressures as well as different Gas-to-solid activation-energy and thermal conductivity ratios. It is observed that increasing overpressure results in a more spatially distributed solid-phase reaction and a rapidly increasing flame-propagation speed. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Univ Calif San Diego, Energy Res Ctr, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. RP Margolis, SB (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM margoli@sandia.gov NR 21 TC 4 Z9 5 U1 0 U2 2 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2087 EP 2095 DI 10.1016/j.proci.2004.07.016 PN 2 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300044 ER PT J AU Molina, A Murphy, JJ Shaddix, CR Blevins, LG AF Molina, A Murphy, JJ Shaddix, CR Blevins, LG TI The effect of potassium bromide and sodium carbonate on coal char combustion reactivity SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE char; coal; reactivity ID FLUIDIZED-BED COMBUSTION; GAS-PHASE KINETICS; FLAME INHIBITION; HYDROGEN BROMIDE; PREMIXED FLAMES; BOUNDARY-LAYER; N2O; NO; EXTINCTION; EMISSIONS AB The addition of halogens, particularly iodine, to the gas during coal char oxidation has been used in previous studies to quench gas-phase chemistry, thereby allowing one to separate the effects of homogeneous and heterogeneous reactions. Halogen addition suppresses the gas-phase radicals to near-equilibrium levels. A similar effect can be expected from other compounds with high efficiency as fire suppressants, such as alkali metals. The effectiveness of the use of additives in distinguishing homogeneous and heterogeneous reactions during char oxidation relies on the assumption that radicals are suppressed while heterogeneous reactions occurring on the char surface are not affected. The present work tests this assumption for potassium bromide (KBr) and sodium carbonate (Na2CO3) reacting with a pulverized eastern bituminous coal char during oxidation. An increase in CO and a slight reduction in particle temperature were observed with the addition of KBr, consistent with known effects of halogens on gas-phase chemistry. An increase in particle size was also observed with the KBr addition. This observation and the results of model calculations suggest that there is significant incorporation of liquid KBr on the char surface under the conditions examined. With Na2CO3 addition, the particle temperature did not change, the particle size showed a slight decrease, and CO production increased. Although the mechanisms for Na interaction with radicals at combustion conditions are not well established, char oxidation modeling suggests that a decrease in OH concentration in the particle boundary layer is the cause for the observed increase in CO production. It is concluded that Na2CO3 has clear advantages over KBr for inhibiting gas-phase chemistry without affecting char oxidation for the conditions investigated here. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Molina, A (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. EM amolina@sandia.gov NR 42 TC 9 Z9 9 U1 0 U2 16 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2187 EP 2195 DI 10.1016/j.proci.2004.08.219 PN 2 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300055 ER PT J AU Maloney, DJ Monazam, ER Casleton, KH Shaddix, CR AF Maloney, DJ Monazam, ER Casleton, KH Shaddix, CR TI Evaluation of char combustion models: measurement and analysis of variability in char particle size and density SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago ID PULVERIZED-COAL COMBUSTION; DISTRIBUTIONS; KINETICS; BURNOUT; BALANCE; MASS AB Char samples representing a range of combustion conditions and extents of burnout were obtained from a well-characterized laminar flow combustion experiment. Individual particles from the parent coal and char samples were characterized to determine distributions in particle volume, mass, and density at different extent of burnout. The data were then compared with predictions from a comprehensive char combustion model referred to as the char burnout kinetics model (CBK). The data clearly reflect the particle-to-particle heterogeneity of the parent coal and show a significant broadening in the size and density distributions of the chars resulting from both devolatilization and combustion. Data for chars prepared in a lower oxygen content environment (6% oxygen by vol.) are consistent with zone 11 type combustion behavior where most of the combustion is occurring near the particle Surface. At higher oxygen contents (12% by vol.), the data show indications of more burning occurring in the particle interior. The CBK model does a good job of predicting the general nature of the development of size and density distributions during burning but the input distribution of particle size and density is critical to obtaining good predictions. A significant reduction in particle size was observed to occur as a result of devolatilization. For comprehensive combustion models to provide accurate predictions, this size reduction phenomenon needs to be included in devolatilization models so that representative char distributions are carried through the calculations. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Natl Energy Technol Lab, Morgantown, WV USA. REM Engn, Morgantown, WV USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA USA. RP Maloney, DJ (reprint author), Natl Energy Technol Lab, Morgantown, WV USA. EM dmalon@netl.doe.gov NR 18 TC 10 Z9 10 U1 0 U2 7 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2197 EP 2204 DI 10.1016/j.proci.2004.08.093 PN 2 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300056 ER PT J AU Korobeinichev, OP Shvartsberg, VM Shmakov, AG Bolshova, TA Jayaweera, TM Melius, CF Pitz, WJ Westbrook, CK Curran, HJ AF Korobeinichev, OP Shvartsberg, VM Shmakov, AG Bolshova, TA Jayaweera, TM Melius, CF Pitz, WJ Westbrook, CK Curran, HJ TI Flame inhibition by phosphorus-containing compounds in lean and rich propane flames SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE phosphorus; inhibition; premixed flames; thermochemistry; modeling ID ADIABATIC BURNING VELOCITY; ORGANOPHOSPHORUS COMPOUNDS; DIMETHYL METHYLPHOSPHONATE; DESTRUCTION CHEMISTRY; H+OH RECOMBINATION; OXYGEN FLAMES; METHANE-AIR; COMBUSTION; HYDROGEN; DMMP AB Chemical inhibition of laminar propane flames by organophosphorus compounds has been studied experimentally and computationally using a detailed chemical kinetic reaction mechanism. Both fuel-lean and fuel-rich propane flames were studied to examine the role of equivalence ratio in flame inhibition. The experiments examined a wide variety of organophosphorus compounds. We report on experimental species flame profiles for tri-methyl phosphate (TMP) and compare them with modeled species flame profile results of TMP and di-methyl methyl phosphonate (DMMP). Both experiments and kinetic modeling indicate that inhibition efficiency is effectively the same for all of the organophosphorus compounds examined, independent of the molecular structure of the initial inhibitor molecule. Chemical inhibition is due to reactions involving small P-bearing species HOPO(2) and HOPO produced by the organophosphorus compounds (OPCs). Ratios of HOPO(2) and HOPO concentrations differ between lean and rich flames, with HOPO(2) dominant in lean flames while HOPO dominates in rich flames. Resulting HOPO(2) and HOPO species profiles do not significantly depend on the initial source of the HOPO(2) and HOPO, and thus are relatively insensitive to the initial OPC inhibitor. A more generalized form of the Twarowski mechanism is developed to account for the results observed, and new theoretical values are determined for heats of formation of the important P-containing species, using the BAC-G2 method. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Russian Acad Sci, Inst Chem Kinet & Combust, Novosibirsk 630090, Russia. Natl Univ Ireland Univ Coll Galway, Dept Chem, Galway, Ireland. RP Westbrook, CK (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. EM westbrook1@llnl.gov RI Shvartsberg, Vladimir/B-1045-2014; Shmakov, Andrey/A-9996-2014; OI Curran, Henry/0000-0002-5124-8562 NR 40 TC 9 Z9 12 U1 0 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1540-7489 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2353 EP 2360 DI 10.1016/j.proci.2004.08.095 PN 2 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300075 ER PT J AU Andac, MG Egolfopoulos, FN Campbell, CS Lee, JC AF Andac, MG Egolfopoulos, FN Campbell, CS Lee, JC TI Effects of combustible dust clouds on premixed flame extinction in normal- and micro-gravity SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE flame extinction; particles; laminar flames; two-phase flows; micro-gravity ID PARTICLE IGNITION; INERT PARTICLES; CARBON PARTICLE; LAMINAR AB An experimental and numerical study was carried out on the effects of combustible solid particles on the extinction of atmospheric, strained, laminar premixed methane/air, and propane/air flames in normal- and micro-gravity. The study was conducted in the opposed-jet configuration in which single flames were stabilized either below or above the gas stagnation plane by counter-flowing a reacting mixture against ambient-temperature air. Spherical 50-mu m glassy-carbon and 32-mu m Lycopodium particles were injected from either the mixture or the air sides, and the flame extinction states were experimentally determined. The results provided insight into the effects of fuel type, gas-phase composition, strain rate, gravity, as well as particle type, number density, and injection orientation. The combustible particles could have a negative or positive effect oil the gas-phase reactivity, depending on the prevailing strain rate and the orientation of injection. The effect of combustible particles on flame extinction was found to reverse when the orientation of the particle seeding is reversed. Experiments and simulations revealed that particle reactions that are not possible in upstream seeding become possible in downstream seeding due to differences in particle residence times and prevailing temperature fields. The effects of gravity on the particle-gas interactions were identified and explained. Gravity could notably modify the chemical response of reacting particles, which, in turn, affects the extinction behavior of the gas phase. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ So Calif, Dept Aerosp & Mech Engn, Los Angeles, CA 90089 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Andac, MG (reprint author), Univ So Calif, Dept Aerosp & Mech Engn, Los Angeles, CA 90089 USA. EM aiidac@usc.edu RI Campbell, Charles/C-3653-2008; OI Egolfopoulos, Fokion/0000-0002-7115-5304 NR 19 TC 0 Z9 0 U1 0 U2 2 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2369 EP 2377 DI 10.1016/j.proci.2004.08.256 PN 2 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300077 ER PT J AU Ahn, JM Eastwood, C Sitzki, L Ronney, PD AF Ahn, JM Eastwood, C Sitzki, L Ronney, PD TI Gas-phase and catalytic combustion in heat-recirculating burners SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE micro-combustors; micro-combustion; flameless combustion; extinction limits; catalytic combustion ID GENERATION; MIXTURES; LIMITS AB An experimental study of a spiral counterflow "Swiss roll" burner was conducted, with emphasis on the determination of extinction limits and comparison of results with and without bare-metal Pt catalyst. A wide range of Reynolds numbers (Re) were tested using propane-air mixtures. Both lean and rich extinction limits were extended with the catalyst, though rich limits were extended much further. With the catalyst, combustion could be sustained at Re as low as 1.2 with peak temperatures as low as 350 K. A heat transfer parameter characterizing the thermal performance of both gas-phase and catalytic combustion at all Re was identified. At low Re, the "lean" extinction limit was actually rich of stoichiometric, and rich-limit had equivalence ratios exceeded 40 in some cases. No corresponding behavior was observed without the catalyst. Gas-phase combustion, in general, Occurred in a "flameless" mode near the burner center. With or without catalyst, for sufficiently robust conditions (high Re, near-stoichiometric) not requiring heat recirculation, a visible flame would propagate out of the center, but this flame could only be re-centered if the catalyst were present. Gas chromatography indicated that at low Re, even in extremely rich mixtures, CO and non-propane hydrocarbons did not form. For higher Re, where both gas-phase and catalytic combustion could occur, catalytic limits were slightly broader but had much lower limit temperatures. At sufficiently high Re, catalytic and gas-phase limits merged. It is concluded that combustion at low Re in heat-recirculating burners greatly benefits from catalytic combustion with the proper choice of mixtures that are different from those preferred for gas-phase combustion. In particular, the importance of providing a reducing environment for the catalyst to enhance O-2 desorption, especially at low Re where heat losses are severe thus peak temperatures are low, is noted. (c) 2004 Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Univ So Calif, Dept Aeronaut & Mech Engn, Los Angeles, CA 90089 USA. RP Eastwood, C (reprint author), Lawrence Livermore Natl Lab, Livermore, CA USA. EM Eastwood2@llnl.gov RI Ronney, Paul/B-4007-2009 OI Ronney, Paul/0000-0002-2779-6438 NR 15 TC 148 Z9 166 U1 4 U2 56 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2463 EP 2472 DI 10.1016/j.proci.2004.08.265 PN 2 PG 10 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300085 ER PT J AU Mack, JH Flowers, DL Buchholz, BA Dibble, RW AF Mack, JH Flowers, DL Buchholz, BA Dibble, RW TI Investigation of HCCI combustion of diethyl ether and ethanol mixtures using carbon 14 tracing and numerical simulations SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE HCCI; HCCI modeling; mass spectrometry; biofuel; combustion efficiency ID OXIDATION; AMS AB Despite the rapid combustion typically experienced in homogeneous charge compression ignition (HCCI), components in fuel mixtures do not ignite in unison or burn equally. In our experiments and modeling of blends of diethyl ether (DEE) and ethanol (EtOH), the DEE led combustion and proceeded further toward completion, as indicated by C-14 isotope tracing, A numerical model of HCCI combustion of DEE and EtOH mixtures supports the isotopic findings. Although both approaches lacked information oil incompletely combusted intermediates plentiful in HCCI emissions, the numerical model and 14C tracing data agreed within the limitations of the single zone model. Despite the fact that DEE is more reactive than EtOH in HCCI engines, they are sufficiently similar that we did not observe a large elongation of energy release or significant reduction in inlet temperature required for light-off, both desired effects for the combustion event. This finding suggests that, in general, HCCI combustion of fuel blends may have preferential combustion of some of the blend components. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Calif Berkeley, Combust Anal Lab, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. RP Mack, JH (reprint author), Univ Calif Berkeley, Combust Anal Lab, Berkeley, CA 94720 USA. EM hmack@me.berkeley.edu RI Buchholz, Bruce/G-1356-2011; OI Mack, John Hunter/0000-0002-5455-8611 NR 29 TC 31 Z9 32 U1 2 U2 9 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2693 EP 2700 DI 10.1016/j.proci.2004.08.136 PN 2 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300111 ER PT J AU Sjoberg, M Dec, JE AF Sjoberg, M Dec, JE TI An investigation into lowest acceptable combustion temperatures for hydrocarbon fuels in HCCI engines SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE HCCI; CO oxidation; peak temperature ID OXIDATION AB The combustion temperatures required for complete combustion in homogeneous charge compression ignition engines have been investigated computationally and experimentally. Fuels from several different hydrocarbon classes are covered including: iso-octane, n-heptane, toluene, and methylcyclohexane. Over a wide range of conditions, it was found that the temperature requirements are well described by the peak cycle temperature. For operation with a compression ratio of 18 at an engine speed of 1200 rpm, 1500 K is needed for the CO-to-CO2 reactions to go to completion before the combustion is quenched by piston expansion. CO oxidation does not go to completion for operation with peak temperature below 1500 K since the OH level becomes too low. The required peak combustion temperature was found to be independent of fuel-type and autoignition characteristics. This occurs because the final CO oxidation process is independent of the original fuel molecule structure. Additionally, the combustion phasing relative to top-dead-center surprisingly has no influence on the required peak combustion temperature. This happens because the time spent close to the peak temperature does not change much with combustion phasing for operation that has slow, but complete, CO oxidation. The onset of CO emissions is more gradual for the experiment compared to the single-zone model. This can be attributed to an in-cylinder thermal distribution caused by crevices and a thermal boundary layer. Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Sjoberg, M (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM mgsjobe@sandia.gov NR 17 TC 58 Z9 59 U1 2 U2 5 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2719 EP 2726 DI 10.1016/j.proci.2004.08.132 PN 2 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300114 ER PT J AU Pickett, LM AF Pickett, LM TI Low flame temperature limits for mixing-controlled Diesel combustion SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE Diesel combustion; sprays; NOx; HCCI; engines AB The low flame temperature limits for mixing-controlled Diesel combustion were investigated in a constant-volume combustion chamber at well-defined ambient conditions. Flame temperatures were controlled by varying ambient oxygen concentration or by using fuel-lean mixing-controlled combustion. Pressure rise measurements show that combustion efficiency remains high for flame temperatures as low as 1500-1600 K for conditions where the ambient gas temperature was greater than 1000 K. This low flame temperature limit is less than those of propagating flame processes in engines but close to that of HCCI combustion. Chemiluminescence imaging shows that a cool flame exists prior to the quasi-steady lift-off length, suggesting that ignition processes are continuously occurring within the Diesel fuel jet as air and fuel mix upstream of the high-temperature reaction zone at the lift-off length. Published by Elsevier Inc. on behalf of The Combustion Institute. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Pickett, LM (reprint author), Sandia Natl Labs, POB 969,MS 9053, Livermore, CA 94551 USA. EM LMPicke@sandia.gov NR 13 TC 30 Z9 32 U1 0 U2 5 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2727 EP 2735 DI 10.1016/j.proci.2004.08.187 PN 2 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300115 ER PT J AU Zhu, JY Lee, KO Yozgatligil, A Choi, MY AF Zhu, JY Lee, KO Yozgatligil, A Choi, MY TI Effects of engine operating conditions on morphology, microstructure, and fractal geometry of light-duty diesel engine particulates SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago ID CARBON; GRAPHITE AB An investigation on the morphology, internal microstructure, and fractal geometry of particulate matter (PM) was conducted for a 1.7-L light-duty diesel engine. The experimental and analytical instruments used in this study include a unique thermophoretic sampling system, a high-resolution transmission electron microscope (TEM), customized digital image processing/data acquisition system, and a Raman scattering spectrometer that have been extensively used at Argonne National Laboratory. During experiments, diesel particulates were directly collected from the exhaust stream. In the morphological observations using TEM, graphitic crystallite structures were found from these light-duty diesel particulates, particularly at high engine loads. In subsequent analysis, Raman spectra revealed details of these graphitic structures quantitatively: the collected diesel PM was quite similar in atomic structures to typical graphite, and the degree of its crystalline structures increased as the engine load increased. in PM size measurements, mean primary particle diameters (d(p)) are in a range of 19.4-32.5 nm and radii of gyration (R,) in a range of 77.4-134.1 urn, respectively, across the engine operating conditions of 780-4000 rpm and 0-100%, loads. From the fractal analysis, smaller fractal dimensions (D-f) (1.46-1.70) were measured for the light-duty diesel engine used in this study, compared to those of heavy-duty diesel particulates that ranged in 1.80-1.88. This result implies that more stretched chain-like particles were produced from the light-duty engine under the diffusion-limit formation mechanism. The database on the physical dimension and fractal geometry of light-duty diesel PM obtained from this study offers data for the future standards of diesel PM sizes and development of advanced diesel PM emission control technologies. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Argonne Natl Lab, Transportat Technol R&D Ctr, Argonne, IL 60439 USA. Drexel Univ, Dept Mech Engn & Mech, Philadelphia, PA 19014 USA. RP Zhu, JY (reprint author), Argonne Natl Lab, Transportat Technol R&D Ctr, Argonne, IL 60439 USA. EM jzliu@anl.gov RI Yozgatligil, Ahmet/A-9682-2016 OI Yozgatligil, Ahmet/0000-0002-7655-7695 NR 25 TC 90 Z9 106 U1 0 U2 20 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2781 EP 2789 DI 10.1016/j.proci.2004.08.232 PN 2 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300121 ER PT J AU Johnson, MR Littlejohn, D Nazeer, WA Smith, KO Cheng, RK AF Johnson, MR Littlejohn, D Nazeer, WA Smith, KO Cheng, RK TI A comparison of the flowfields and emissions of high-swirl injectors and low-swirl injectors for lean premixed gas turbines SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE gas turbines; lean premixed; swirl; NOx; emissions ID COMBUSTION; BURNER; VELOCITY; BOILERS; FLAMES AB A new approach for low emission gas turbines was investigated by modifying a typical production high-swirl injector (HSI) for gas turbine combustors to operate in a novel low-swirl mode (LSI). This LSI (S = 0.5) was configured in the laboratory and investigated by particle image velocimetry at firing rates of 9-87 kW (1 < U-0 < 10 m/s). It was also tested at simulated gas turbine conditions of 0.08-2.2 MW (20 < U-0 < 50 m/s) at elevated combustion inlet temperatures (230 < T-0 < 430 degrees C) and pressures (6 < P-0 < 15 atm). The results were compared with those obtained with a HSI (S = 0.73). The PIV results show that the flowfields of the LSI are devoid of a large dominant recirculation zone. This is fundamentally different than the strong and large recirculation regions that dominate flowfields of the HSI. Under simulated engine conditions, the LSI has the same operating range as the HSI. Its NOx emissions were about 60% lower than the HSI, and its CO emissions were comparable. The lack of a strong recirculation zone and the shorter residence time within the LSI may provide an explanation for the NOx reduction. These results demonstrate that the LSI is a promising solution for attaining an ultra-low emissions target of < 5 ppm NOx (15% O-2) in gas turbines. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Solar Turbines Inc, Adv Combust Engn, San Diego, CA 92186 USA. RP Cheng, RK (reprint author), Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. EM RKCheng@lbl.gov RI Johnson, Matthew/F-2672-2010 OI Johnson, Matthew/0000-0002-3637-9919 NR 19 TC 76 Z9 83 U1 4 U2 30 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2867 EP 2874 DI 10.1016/j.proci.2004.07.040 PN 2 PG 8 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300131 ER PT J AU Wicksall, DM Agrawal, AK Schefer, RW Keller, JO AF Wicksall, DM Agrawal, AK Schefer, RW Keller, JO TI The interaction of flame and flow field in a lean premixed swirl-stabilized combustor operated on H-2/CH4/air SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE gas turbine engines; premixed turbulent flames; laser- induced fluorescence ID JET FLAMES; CH; VELOCITY AB The interaction of flame and flow field was studied in an enclosed lean premixed swirl-stabilized combustor operated on methane (CH4)- and hydrogen (H-2)- enriched CH4. This was accomplished by simultaneous measurements of the 2D velocity field using particle image velocimetry and planar laser induced fluorescence imaging of the hydroxyl (OH) radical. Experiments were conducted at an inlet Reynolds number of 13,500 and a theoretical swirl number of 1.5. The fuel was pure CH4 or a mixture of 60% CH4 and 40% H-2 by volume. The adiabatic flame temperature was 1350 +/- 20 degrees C for both fuels. Results show that the addition of H-2 changes the shape of the reaction zone, producing a shorter, and a more robust flame. Fuel composition also affected the location of the reaction zone, which in turn, influenced both instantaneous and time-averaged flow fields. Time-resolved measurements show vortical structures containing regions of high OH concentration around their edges. The combustion stabilized in regions of high compressive strain for the CH4 flame but not for the H-2-enriched CH4 flame. In the CH4 flame, reactions extinguished in the high velocity inlet jet region, where the H-2-enriched CH4 flame was able to sustain combustion. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Univ Oklahoma, Sch Aerosp & Mech Engn, Norman, OK 73019 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Agrawal, AK (reprint author), Univ Oklahoma, Sch Aerosp & Mech Engn, Norman, OK 73019 USA. EM aagrawal@ou.edu RI Agrawal, Ajay/B-5304-2010; Schefer, Jurg/G-3960-2012 NR 18 TC 41 Z9 42 U1 1 U2 14 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2875 EP 2883 DI 10.1016/j.proci.2004.07.021 PN 2 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300132 ER PT J AU Oefelein, JC AF Oefelein, JC TI Thermophysical characteristics of shear-coaxial LOX-H-2 flames at supercritical pressure SO PROCEEDINGS OF THE COMBUSTION INSTITUTE LA English DT Article; Proceedings Paper CT 30th International Symposium on Combustion CY JUL 25-30, 2004 CL Univ Illinois Chicago, Chicago, IL SP Combust Inst HO Univ Illinois Chicago DE turbulent combustion; cryogenic propellants; supercritical pressure; flame structure; liquid-rocket propulsion ID CORRESPONDING STATES; TRANSPORT-PROPERTIES; PREDICTION; MIXTURES; FLUIDS; COMBUSTION; INJECTION; PRINCIPLE AB The thermophysical characteristics of a liquid-oxygen-hydrogen flame at supercritical pressure are investigated, with emphasis placed on the near-field region just downstream of a shear-coaxial injector element. Results are presented from a series of hierarchical high-fidelity simulations for a condition where oxygen is injected in a cryogenic state, at a subcritical temperature and supercritical pressure, and hydrogen is injected in a supercritical state. This condition has significant technical relevance in liquid-rocket engines, but is not well understood and has not been well quantified to date. For this situation, a diffusion dominated mode of combustion occurs in the presence of exceedingly large thermophysical property gradients. The flame anchors itself in the interfacial region of high shear that exists between the liquid-oxygen core and the annular hydrogen jet, and intensifies the respective property gradients such that they approach the behavior of a contact discontinuity. Significant real-gas effects and transport anomalies coexist locally in colder regions of the flow, with ideal gas and transport characteristics occurring within the flame zone. The current analysis provides one of the first quantitative characterizations of the flame structure and associated property variations in liquid-oxygen-hydrogen flames at supercritical pressure. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Oefelein, JC (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM oefelei@sandia.gov NR 23 TC 44 Z9 44 U1 0 U2 7 PU COMBUSTION INST PI PITTSBURGH PA 5001 BAUM BOULEVARD, STE 635, PITTSBURGH, PA 15213-1851 USA SN 0082-0784 J9 P COMBUST INST JI Proc. Combust. Inst. PY 2005 VL 30 BP 2929 EP 2937 DI 10.1016/j.proci.2004.08.212 PN 2 PG 9 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 937RX UT WOS:000229944300138 ER PT S AU van Breugel, W Bajt, S Bradley, J Bringa, E Dai, Z Felter, T Graham, G Kucheyev, S Torres, D Tielens, A Baragiola, R Dukes, C Loeffler, M AF van Breugel, W Bajt, S Bradley, J Bringa, E Dai, Z Felter, T Graham, G Kucheyev, S Torres, D Tielens, A Baragiola, R Dukes, C Loeffler, M BE Wilson, A TI Star formation in high pressure, high energy density environments: Laboratory experiments of ISM dust analogs SO PROCEEDINGS OF THE DUSTY AND MOLECULAR UNIVERSE: A PRELUDE TO HERSCHEL AND ALMA SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT Conference on the Dusty and Molecular Universe CY OCT 27-29, 2004 CL Paris, FRANCE SP Minist Rech, Observ Paris, Minist Educ Natl, CNES, Inst Natl Sci Univers, CNRS, European So Observ, European Space Agcy DE interstellar medium; dust; star formation; galaxy formation; active black holes; cosmic rays; laboratory experiments. ID GRAINS; ICE AB Dust grains control the chemistry and cooling, and thus the gravitational collapse of interstellar clouds. Energetic particles, shocks and ionizing radiation can have a profound influence on the structure, lifetime and chemical reactivity of the dust, and therefore on the star formation efficiency. This would be especially important in forming galaxies, which exhibit powerful starburst (supernovae) and AGN (active galactic nucleus) activity. How dust properties are affected in such environments may be crucial for a proper understanding of galaxy formation and evolution. We present the results of experiments at LLNL which show that irradiation of the interstellar medium (ISM) dust analog forsterite (Mg2SiO4) with swift heavy ions (10 MeV Xe) and a large electronic energy deposition amorphizes its crystalline structure, without changing its chemical composition. From our data we predict that silicate grains in the ISM, even in dense and cold giant molecular clouds, can be amorphized by heavy cosmic rays (CR's). This might provide an explanation for the observed absence of crystalline dust in the ISM clouds of our Milky Way galaxy. This processing of dust by CR's would be even more important in forming galaxies and galaxies with active black holes. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP van Breugel, W (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI Bringa, Eduardo/F-8918-2011 NR 11 TC 0 Z9 0 U1 1 U2 1 PU ESA PUBLICATIONS DIVISION C/O ESTEC PI 2200 AG NOORDWIJK PA PO BOX 299, 2200 AG NOORDWIJK, NETHERLANDS SN 0379-6566 J9 ESA SP PUBL PY 2005 VL 577 BP 91 EP 92 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BBR24 UT WOS:000227350800015 ER PT S AU Pawar, RJ Zyvoloski, GA Tenma, N Sakamoto, Y Komai, T AF Pawar, RJ Zyvoloski, GA Tenma, N Sakamoto, Y Komai, T GP ISOPE TI Numerical simulation of laboratory experiments on methane hydrate dissociation SO PROCEEDINGS OF THE FIFTEENTH (2005) INTERNATIONAL OFFSHORE AND POLAR ENGINEERING CONFERENCE, VOL 1 SE International Offshore and Polar Engineering Conference Proceedings LA English DT Proceedings Paper CT 15th International Offshore and Polar Engineering Conference (ISOPE 2005) CY JUN 19-24, 2005 CL Seoul, SOUTH KOREA DE gas hydrate; methane; dissociation; reformulation; kinetics; porous media simulation; hot water injection AB We present results of numerical simulation of dissociation behavior of methane hydrates in laboratory experiments conducted at the Institute for Geo-Resources and Environment in Tsukuba, Japan. The hydrate was formed in packed sand columns and the dissociation behavior was studied under different stimulation conditions including hot-water injection and/or pressure reduction. A number of variables including amount of gas produced, temperature along the column and pressure difference across the column were monitored. A numerical model for hydrate behavior was developed, based on the FEHM (Finite Element Heat and Mass) Computer Code, the Los Alamos National Laboratory (LANL)'s in-house porous flow simulator. Capability to simulate the general behavior of hydrates in porous media was added to the simulator, including the kinetic, thermodynamic and heat transfer processes. Multiple conceptual models were used to simulate the experimental data. The simulation results indicate that incorporation of both dissociation and hydrate formation is necessary to better match the experimental data. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki, Japan. RP Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU INTERNATIONAL SOCIETY OFFSHORE& POLAR ENGINEERS PI CUPERTINO PA PO BOX 189, CUPERTINO, CA 95015-0189 USA SN 1098-6189 BN 1-880653-64-8 J9 INT OFFSHORE POLAR E PY 2005 BP 379 EP + PG 3 WC Engineering, Ocean SC Engineering GA BCZ19 UT WOS:000232029800059 ER PT B AU Ding, C Ye, JP AF Ding, Chris Ye, Jieping BE Kargupta, H Srivastava, J Kamath, C Goodman, A TI 2-Dimensional Singular Value Decomposition for 2D Maps and Images SO PROCEEDINGS OF THE FIFTH SIAM INTERNATIONAL CONFERENCE ON DATA MINING SE SIAM Proceedings Series LA English DT Proceedings Paper CT 5th SIAM International Conference on Data Mining CY APR 21-23, 2005 CL Newport Beach, CA SP SIAM, Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Amer Stat Assoc AB For a set of 1D vectors, standard singular value decomposition (SVD) is frequently applied. For a set of 2D objects such as images or weather maps, we form 2dSVD, which computes principal eigenvectors of row-row and column-column covariance matrices, exactly as in the standard SVD. We study optimality properties of 2dSVD as low-rank approximation and show that it provides a framework unifying two recent approaches. Experiments on images and weather maps illustrate the usefulness of 2dSVD. C1 [Ding, Chris] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ding, C (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM chqding@lbl.gov; jieping@cs.umn.edu NR 16 TC 32 Z9 34 U1 0 U2 1 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 978-0-89871-593-4 J9 SIAM PROC S PY 2005 BP 32 EP 43 PG 12 WC Computer Science, Artificial Intelligence SC Computer Science GA BUJ08 UT WOS:000289491000004 ER PT B AU Ding, C He, XF Simon, HD AF Ding, Chris He, Xiaofeng Simon, Horst D. BE Kargupta, H Srivastava, J Kamath, C Goodman, A TI On the Equivalence of Nonnegative Matrix Factorization and Spectral Clustering SO PROCEEDINGS OF THE FIFTH SIAM INTERNATIONAL CONFERENCE ON DATA MINING SE SIAM Proceedings Series LA English DT Proceedings Paper CT 5th SIAM International Conference on Data Mining CY APR 21-23, 2005 CL Newport Beach, CA SP SIAM, Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Amer Stat Assoc ID PARTS AB Current nonnegative matrix factorization (NMF) deals with X = FG(T) type. We provide a systematic analysis and extensions of NMF to the symmetric W = HH(T), and the weighted W = HSH(T). We show that (1) W = HH(T) is equivalent to Kernel K-means clustering and the Laplacian-based spectral clustering. (2) X = FG(T) is equivalent to simultaneous clustering of rows and columns of a bipartite graph. Algorithms are given for computing these symmetric NMFs. C1 [Ding, Chris; He, Xiaofeng; Simon, Horst D.] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ding, C (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM chqding@lbl.gov; xhe@lbl.gov; hdsimon@lbl.gov NR 15 TC 168 Z9 181 U1 2 U2 5 PU SIAM PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA BN 978-0-89871-593-4 J9 SIAM PROC S PY 2005 BP 606 EP 610 PG 5 WC Computer Science, Artificial Intelligence SC Computer Science GA BUJ08 UT WOS:000289491000070 ER PT B AU Sun, AC Moffat, HK Enos, DG Glauner, CS AF Sun, AC Moffat, HK Enos, DG Glauner, CS GP IEEE TI Pore corrosion model for gold-plated copper contacts SO Proceedings of the Fifty-First IEEE Holm Conference on Electrical Contacts LA English DT Proceedings Paper CT 51st IEEE Holm Conference on Electrical Contacts CY SEP 26-28, 2005 CL Chicago, IL SP IEEE, Components, Package, & Mfg Technol Soc DE component; corrosion; copper sulfidation; interconnects; Au-plated copper; electrical contact resistance ID SURFACES AB The research goal presented here is to model the electrical response of gold plated copper electrical contacts exposed to a mixed flowing gas stream consisting of air containing 10ppb H2S at 30 degrees C and a relative humidity of 70%. This environment accelerates the attack normally observed in a light industrial environment (similar to, but less severe than, the Battelle class 2 environment). Corrosion rates were quantified by measuring the corrosion site density, size distribution, and the electrical resistance of a probe contact with the aged surface, as a function of exposure time. A pore corrosion numerical model was used to predict both the growth of copper sulfide corrosion product which blooms through defects in the gold layer and the resulting electrical contact resistance of the aged surface. Assumptions about the distribution of defects in the noble metal plating and the mechanism for how corrosion blooms affect electrical contact resistance were needed to close the numerical model. Comparisons are made to the experimentally observed corrosion-bloom number density, bloom size distribution, and the cumulative probability distribution of the electrical contact 4 resistance. Experimentally, the bloom site density increases as a function of time, whereas the bloom size distribution remains relatively independent of time. These two effects are included in the numerical model by adding a corrosion initiation probability proportional to the surface area and a probability for bloom-growth extinction proportional to the bloom volume, due to Kirkendall voiding. The cumulative probability distribution of electrical resistance becomes skewed as exposure time increases. While the resistance increases as a function of time for a fraction of the bloom population, the median value remains relatively unchanged. In order to model this behavior, the resistance calculated for large blooms is heavily weighted by contributions from the halo region. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sun, AC (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 1 Z9 1 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-9113-6 PY 2005 BP 232 EP 237 DI 10.1109/HOLM.2005.1518249 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BDK00 UT WOS:000233937700034 ER PT B AU Dickrell, DJ Dugger, MT AF Dickrell, DJ Dugger, MT GP IEEE TI The effects of surface contamination on resistance degradation of hot-switched low-force MEMS electrical contacts SO Proceedings of the Fifty-First IEEE Holm Conference on Electrical Contacts LA English DT Proceedings Paper CT 51st IEEE Holm Conference on Electrical Contacts CY SEP 26-28, 2005 CL Chicago, IL SP IEEE, Components, Package, & Mfg Technol Soc DE MEMS; contamination; hot-switched; degradation; gold; platinum; arcing AB This work investigated the relationship between the resistance degradation in low-force metal contacts and hot-switched operational conditions representative of MEMS devices. A modified nano-indentation apparatus was used to bring electrically-biased gold and platinum surfaces into contact at a load of 100 mu N. The applied normal force and electrical contact resistance of the contact materials was measured simultaneously. The influence of parallel discharge paths for stored electrical energy in the contact circuit is discussed in relation to surface contamination decomposition and the observed resistance degradation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dickrell, DJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 14 Z9 14 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-9113-6 PY 2005 BP 255 EP 258 DI 10.1109/HOLM.2005.1518252 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BDK00 UT WOS:000233937700037 ER PT B AU Bell, JB Day, MS Beckner, VE Rendleman, CA Kuhl, A Neuwald, P AF Bell, JB Day, MS Beckner, VE Rendleman, CA Kuhl, A Neuwald, P GP IEEE Comp Soc TI Numerical simulation of shock-dispersed fuel charges SO Proceedings of the HPCMP, Users Group Conference 2005 LA English DT Proceedings Paper CT Annual Conference on High Performance Computing Modernization Program CY JUN 27, 2005-JUN 30, 2006 CL Nashville, TN SP DoD Sci & Technol Comm, User Advocacy Grp, HPCMPO Outreach Team, US Dept Defense, UGC C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Bell, JB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-2496-6 PY 2005 BP 198 EP 201 PG 4 WC Computer Science, Interdisciplinary Applications; Multidisciplinary Sciences SC Computer Science; Science & Technology - Other Topics GA BEA11 UT WOS:000236397600029 ER PT S AU Candy, JV Sullivan, EJ AF Candy, JV Sullivan, EJ GP IEEE TI Cancelling tow ship noise using an adaptive model-based approach SO PROCEEDINGS OF THE IEEE/OES EIGHTH WORKING CONFERENCE ON CURRENT MEASUREMENT TECHNOLOGY - PROCEEDINGS SE IEEE Working Conference on Current Measurement Technology LA English DT Proceedings Paper CT 8th Working Conference on Current Measurement Technology CY JUN 28-29, 2005 CL Stoughton, WI SP IEEE, OES AB Ship noise is a major contributor to towed array measurement uncertainties that can lead to large estimation errors. Many approaches ignore this problem, since they rely on inherent narrowband processing to remove these effects. The overall signal-to-noise ratio (SNR) available is therefore decreased making the signal extraction problem more difficult. In this paper we discuss the development of an adaptive model-based processor (AMBP) for signal enhancement from a set of noisy hydrophone measurements contaminated with tow ship noise. These results provide a solution to the adaptive joint cancellation/signal enhancement problem. Here we concentrate on the underlying theoretical development demonstrating the relationship between the canceller and model-based signal enhancer. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Candy, JV (reprint author), Lawrence Livermore Natl Lab, POB 808,L-156, Livermore, CA 94551 USA. EM candy1@llnl.gov; paddypriest@aol.com NR 11 TC 2 Z9 6 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1085-7990 BN 0-7803-8989-1 J9 WORK C CURR MEASUREM PY 2005 BP 14 EP 18 DI 10.1109/CCM.2005.1506325 PG 5 WC Acoustics; Instruments & Instrumentation; Remote Sensing SC Acoustics; Instruments & Instrumentation; Remote Sensing GA BCS53 UT WOS:000231050900002 ER PT B AU Berry, JW Hrozencik, D Rao, S Shen, ZZ AF Berry, JW Hrozencik, D Rao, S Shen, ZZ BE Hu, G TI Finding median set of tree structures in synchronous distributed systems SO Proceedings of the ISCA 20th International Conference on Computers and Their Applications LA English DT Proceedings Paper CT 20th International Conference on Computers and Their Applications CY MAR 16-18, 2005 CL New Orleans, LA SP Int Soc Comp & Appl DE median vertices; synchronous distributed algorithms ID ALGORITHMS; CENTERS AB \Finding the central sets, such as the median sets, of a network topology is a fundamental step in the design and analysis of general distributed systems. This paper presents an alternative synchronous distributed algorithm for finding the median set in general tree structures, based on a revision of a simple sequential algorithm. When this algorithm terminates, every vertex in the tree structure knows the median set of the whole structure, and not just whether or not itself is a median vertex. C1 Sandia Natl Labs, Discrete Math & Algorithms Grp, Livermore, CA 94550 USA. RP Berry, JW (reprint author), Sandia Natl Labs, Discrete Math & Algorithms Grp, Livermore, CA 94550 USA. OI Rao, Shrisha/0000-0003-0625-5103 NR 11 TC 0 Z9 0 U1 0 U2 0 PU INTERNATIONAL SOCIETY COMPUTER S & THEIR APPLICATIONS (ISCA) PI RALEIGH PA 8820 SIX FORKS ROAD, RALEIGH, NC 27615 USA BN 1-880843-54-4 PY 2005 BP 7 EP 12 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA BCB33 UT WOS:000228486500002 ER PT S AU Burke, JJ AF Burke, JJ BE Casa, R Viola, R TI The effect of desiccation date on tuber size distribution and processing quality parameters of four potato cultivars SO Proceedings of the Meeting of the Physiology Section of the European Association for Potato Research SE ACTA HORTICULTURAE LA English DT Proceedings Paper CT Meeting of the Physiology Section of the European-Association-for-Potato-Research CY JUN 14-16, 2004 CL Viterbo, ITALY SP Univ Degli Studi Della Tuscia, Reg Lazio, Coldiretti Viterbo, Consorz Cooperat Ortofrutticolo Alto Viterbese, Assoc Producttori Patate Lazio DE leaf chlorophyll; sucrose; reducing sugar; fry colour ID SEED SIZE; HARVEST; YIELD; CROP; VARIETIES; BULKING; PLANT; TIME AB The effect on canopy integrity, tuber bulking rate, tuber size distribution, dry matter concentration, Maillard reaction substrates and fry colour, from restricting the growing season, by advancing the desiccation date, was investigated for the potato cultivars, 'Fianna', 'Maris Piper', 'Navan' and 'Rooster' during 1996 and 1997. Haulm was desiccated on three dates, with intervals of 10-12 days between desiccations and the tubers graded into nine size categories. Rate of decline in canopy integrity over time, expressed as reduction in radiation interception or in SPAD values, was remarkably consistent between the cultivars 'Fianna', 'Maris Piper', 'Navan' and 'Rooster' over both years. Yield ranking and tuber bulking rate for the cultivars varied between years and between desiccation dates within years. Advancing the desiccation date induced the greatest reductions in yield in the 60-70 mm tuber size grade for cv. 'Maris Piper' and 'Rooster' in 1997 and in the 70-80 mm grade for cv. 'Navan' and 'Fianna'. Restricting the duration of the growing season decreased tuber dry-matter content. Sucrose concentration varied with cultivar, desiccation date and year. Reducing sugar and amino-N concentrations were not consistently effected by the applied treatments. Fry colour following storage was not consistently effected by cultivar or desiccation date and furthermore, concentrations of Maillard reaction substrates were not useful as predictors of chip fry colour following extended storage. C1 TEAGASC, Crops Res Ctr, Carlow, Ireland. RP Burke, JJ (reprint author), TEAGASC, Crops Res Ctr, Oak Pk, Carlow, Ireland. NR 20 TC 0 Z9 0 U1 0 U2 0 PU INTERNATIONAL SOCIETY HORTICULTURAL SCIENCE PI LEUVEN 1 PA PO BOX 500, 3001 LEUVEN 1, BELGIUM SN 0567-7572 BN 90-6605-668-1 J9 ACTA HORTIC PY 2005 IS 684 BP 45 EP 53 PG 9 WC Agronomy SC Agriculture GA BCY53 UT WOS:000231869000006 ER PT B AU Mueller, S Ghosal, D AF Mueller, S Ghosal, D GP IEEE Comp Soc TI Analysis of a distributed algorithm to determine multiple routes with path diversity in ad hoc networks SO PROCEEDINGS OF THE THIRD INTERNATIONAL SYMPOSIUM ON MODELING AND OPTIMIZATION IN MOBILE, AD HOC, AND WIRELESS NETWORKS LA English DT Proceedings Paper CT 3rd International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks CY APR 04-06, 2005 CL Riva del Garda, ITALY SP Create-Net, INRIA, IFIP, ACM, IEEE, ICST, euroNgi, E NEXT, intel, SIEMENS Mobile AB With multipath routing in mobile ad hoc networks (MANETs), a source can establish multiple routes to a destination for routing data. In MANETs, mulitpath routing can be used to provide route resilience, smaller end-to-end delay, and better load balancing. However, when the multiple paths are close together, transmissions of different paths may interfere with each other, causing degradation in performance. Besides interference; the physical diversity of paths also improves fault tolerance. We present a purely distributed multipath protocol based on the AODV-Multipath (AODVM) protocol called AODVM with Path Diversity (AODVM/PD) that finds multiple paths with a desired,degree of correlation between paths specified as an input parameter to the algorithm. We demonstrate through detailed simulation analysis that multiple paths with low degree of correlation determined by AODVM/PD provides both smaller end-to-end delay than AODVM in networks with low mobility and better route resilience in the presence of correlated node failures. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Sandia Natl Labs, Livermore, CA 94550 USA. EM snmuell@sandia.gov; dghosal@ucdavis.edu NR 14 TC 10 Z9 10 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-2267-X PY 2005 BP 277 EP 285 DI 10.1109/WIOPT.2005.12 PG 9 WC Telecommunications SC Telecommunications GA BCP01 UT WOS:000230463100031 ER PT S AU Stockli, MP Leitner, M Moehs, DP Keller, R Welton, RF AF Stockli, MP Leitner, M Moehs, DP Keller, R Welton, RF BE Sherman, JD Belchenko, YI TI Beam dumping ghost signals in electric sweep scanners SO Production and Neutralization of Negative Ions and Beams SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th International Symposium on Production Neutralization of Negative Ions and Beams CY SEP 14-17, 2004 CL Kiev, UKRAINE SP Natl Acad Sci, Los Alamos Natl Lab ID SPALLATION NEUTRON SOURCE; ION-SOURCE; EMITTANCE MEASUREMENTS AB Over the last 20 years many labs started to use Allison scanners to measure low-energy ion beam emittances. We show that large trajectory angles produce ghost signals due to the impact of the beamlet on the electric deflection plates. The strength of the ghost signal is proportional to the amount of beam entering the scanner. Depending on the ions and their velocity, ghost signals can have the opposite polarity as the main beam signals or the same polarity. These ghost signals are easily overlooked because they partly overlap the real signals, they are mostly below the 1% level, and they are often hidden in the noise. However, they cause significant errors in emittance estimates because they are associated with large trajectory angles. The strength of ghost signals, and the associated errors, can be drastically reduced with a simple modification of the deflection plates. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Stockli, MP (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 19 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0248-5 J9 AIP CONF PROC PY 2005 VL 763 BP 145 EP 158 PG 14 WC Physics, Fluids & Plasmas; Physics, Particles & Fields SC Physics GA BCF07 UT WOS:000228995100013 ER PT S AU Moehs, DP AF Moehs, DP BE Sherman, JD Belchenko, YI TI Sub microsecond notching of a negative hydrogen beam at low energy utilizing a magnetron ion source with a split extractor SO Production and Neutralization of Negative Ions and Beams SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th International Symposium on Production Neutralization of Negative Ions and Beams CY SEP 14-17, 2004 CL Kiev, UKRAINE SP Natl Acad Sci, Los Alamos Natl Lab AB A technique for sub-microsecond beam notching is being developed at 20 keV utilizing a Magnetron ion source with a slit extraction system and a split extractor. Each half of the extractor is treated as part of a 50 ohm transmission line which can be pulsed at +/- 700 volts creating a 1400 volt gradient. This system along with the associated electronics is electrically floated on top of a pulsed extraction voltage. A beam reduction of 95% has been observed at the end of the Fermilab 400 MeV Linac and 35% notching has recently been achieved in the Booster. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Moehs, DP (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0248-5 J9 AIP CONF PROC PY 2005 VL 763 BP 189 EP 193 PG 5 WC Physics, Fluids & Plasmas; Physics, Particles & Fields SC Physics GA BCF07 UT WOS:000228995100017 ER PT S AU Sherman, J Chacon-Golcher, E Geros, EG Jacobson, E Lara, P Meyer, BJ Naffziger, P Rouleau, G Schaller, SC Stevens, RR Zaugg, T AF Sherman, J Chacon-Golcher, E Geros, EG Jacobson, E Lara, P Meyer, BJ Naffziger, P Rouleau, G Schaller, SC Stevens, RR Zaugg, T BE Sherman, JD Belchenko, YI TI Physical insights and test stand results for the LANSCE H- surface converter source SO PRODUCTION AND NEUTRALIZATION OF NEGATIVE IONS AND BEAMS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 10th International Symposium on Production Neutralization of Negative Ions and Beams CY SEP 14-17, 2004 CL Kiev, UKRAINE SP Natl Acad Sci, Los Alamos Natl Lab ID ION-SOURCE; PLASMA SOURCES; EXTRACTION AB The Los Alamos Neutron Science Center (LANSCE) H- surface converter source upgrade project has been ongoing for several years to reach 25-40 mA current with 7(pi cm-mrad) lab emittance (95% beam fraction). The duty factor is 12% (120 Hz, 1ms pulse length). Summary test stand results and interpretations for a six filament axial extraction H- source are presented. This source did produce 40-mA H- current, but with unacceptable emittance growth. More recently a fourth modified LANSCE H- production source with radial H- extraction system has been constructed, and is presently undergoing tests. Currents up to 25mA H- have been observed with 20% emittance growth. This emittance growth may be acceptable for 800 MeV linac operations. A summary of physical principles of emittance growth mechanisms and converter physics are given. C1 Los Alamos Natl Lab, LANSCE Div, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, LANSCE Div, POB 1663, Los Alamos, NM 87545 USA. EM jsherrnan@lanl.gov NR 20 TC 11 Z9 11 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0248-5 J9 AIP CONF PROC PY 2005 VL 763 BP 254 EP 266 PG 13 WC Physics, Fluids & Plasmas; Physics, Particles & Fields SC Physics GA BCF07 UT WOS:000228995100024 ER PT S AU Welton, RF Stockli, MP Murray, SN Keller, R AF Welton, RF Stockli, MP Murray, SN Keller, R BE Sherman, JD Belchenko, YI TI Recent advances in the performance and understanding of the SNS* ion source SO Production and Neutralization of Negative Ions and Beams SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th International Symposium on Production Neutralization of Negative Ions and Beams CY SEP 14-17, 2004 CL Kiev, UKRAINE SP Natl Acad Sci, Los Alamos Natl Lab ID SPALLATION NEUTRON SOURCE AB The ion source developed for the Spallation Neutron Source* (SNS) by Lawrence Berkeley National Laboratory (LBNL), is a radio frequency, multi-cusp source designed to produce similar to 40 mA of H- with a normalized rms emittance of less than 0.2 pi mm mrad. To date, the source has been utilized in the commissioning of the SNS accelerator and has already demonstrated stable, satisfactory operation at beam currents of similar to 30 mA with duty-factors of similar to 0.1% for operational periods of several weeks. Once the SNS is fully operational in 2008, a beam current duty-factor of 6% (1 ms pulse length, 60 Hz repetition rate) will be required in order to inject the accelerator. To ascertain the capability of the source to deliver beams at this high duty-factor over sustained time periods, several experimental runs have been conducted, each similar to 1 week in length, in which the ion source was continuously operated on a dedicated test stand. The results of these tests are reported as well as a theory of the Cs release and transport processes which were derived from these data. The theory was then employed to develop a more effective source conditioning procedure as well as an improved Cs collar design. Initial results of tests employing a Cs collar with enhanced surface ionization geometry are also discussed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Welton, RF (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 23 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0248-5 J9 AIP CONF PROC PY 2005 VL 763 BP 296 EP 314 PG 19 WC Physics, Fluids & Plasmas; Physics, Particles & Fields SC Physics GA BCF07 UT WOS:000228995100029 ER PT S AU Ou, FS Saraf, LV Baer, DR AF Ou, FS Saraf, LV Baer, DR BE Brown, GJ Biefeld, RM Gmachl, C Manasreh, MO Unterrainer, K TI Site-specific formation of nanoporous silicon on micro-fabricated silicon surfaces SO PROGRESS IN COMPOUND SEMICONDUCTOR MATERIALS IV-ELECTRONIC AND OPTOELECTRONIC APPLICATIONS SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Progress in Compound Semiconductor Materials IV held at the 2004 MRS Fall Meeting CY NOV 29-DEC 03, 2004 CL Boston, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab ID POROUS SILICON AB We demonstrated an ability to control the location of the porous silicon formation during electro-chemical etching by the introduction of micro-fabricated defects. This ability may open new doors for chemical and biological applications of porous silicon. In this paper, we have focused on the experimental procedure used to form this site-specific porous silicon area on micro-fabricated silicon surface. We also compared our results with work carried out by Saraf et al[1] during the early stage of porous silicon formation in conventional electrochemical etching. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Rensselaer Polytech Inst, Dept Mat Sci & Engn, Troy, NY 12180 USA. RI Baer, Donald/J-6191-2013 OI Baer, Donald/0000-0003-0875-5961 NR 7 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOC PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-777-6 J9 MATER RES SOC SYMP P PY 2005 VL 829 BP 455 EP 459 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics; Physics, Condensed Matter SC Engineering; Materials Science; Optics; Physics GA BCF69 UT WOS:000229084900066 ER PT J AU Lefantzi, S Ray, J Kennedy, CA Najm, HN AF Lefantzi, S Ray, J Kennedy, CA Najm, HN TI A component-based toolkit for simulating reacting flows with high order spatial discretisations on structured adaptively refined meshes SO PROGRESS IN COMPUTATIONAL FLUID DYNAMICS LA English DT Article DE structured adaptive mesh refinement (SAMR); reacting flow; high performance computing; high order spatial interpolations; Common Component Architecture (CCA) ID PARTIAL-DIFFERENTIAL EQUATIONS; PROJECTION METHOD; CHEMISTRY PROBLEMS; AIR FLAMES; STIFF; SCHEMES; METHANE AB We present an innovative methodology for developing scientific and mathematical codes for computational studies of reacting flow, High-order (> 2) spatial discretisations are combined, for the first time, with multi-level block structured adaptively refined meshes (SAMR) to resolve regions of high gradients efficiently. Within the SAMR context, we use 4th order spatial discretisations to achieve the desired numerical accuracy while maintaining a shallow grid hierarchy. We investigate in detail the pairing between the order of the spatial discretisation and the order of the interpolant, and their effect on the overall order of accuracy. These new approaches are implemented in a high performance, component-based architecture (Common Component Architecture) and achieve software re-usability, flexibility and modularity. The high-order approach and the software design are demonstrated and validated on three test cases modelled as reaction-diffusion systems of increasing complexity. We also demonstrate that the 4th order SAMR approach can be computationally more economical compared to second-order approaches. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Ray, J (reprint author), Sandia Natl Labs, POB 969,MS 9056, Livermore, CA 94551 USA. EM slefant@ca.sandia.gov; jairay@ca.sandia.gov; cakenne@speakeasy.net; hnnajm@ca.sandia.gov NR 59 TC 11 Z9 11 U1 0 U2 0 PU INDERSCIENCE ENTERPRISES LTD PI GENEVA PA WORLD TRADE CENTER BLDG, 29 ROUTE DE PRE-BOIS, CASE POSTALE 856, CH-1215 GENEVA, SWITZERLAND SN 1468-4349 EI 1741-5233 J9 PROG COMPUT FLUID DY JI Prog. Comput. Fluid Dyn. PY 2005 VL 5 IS 6 BP 298 EP 315 DI 10.1504/PCFD.2005.007063 PG 18 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA 943IC UT WOS:000230345700002 ER PT J AU Goussis, DA Valorani, M Creta, F Najm, HN AF Goussis, DA Valorani, M Creta, F Najm, HN TI Reactive and reactive-diffusive time scales in stiff reaction-diffusion systems SO PROGRESS IN COMPUTATIONAL FLUID DYNAMICS LA English DT Article DE chemical kinetics; combustion; reduction methods; slow manifolds; intrinsic low-dimensional manifolds; multiple time scales; asymptotic analysis; reaction-diffusion equations ID CHEMICAL-KINETICS; MANIFOLDS AB Two different sets of time scales arising in stiff systems of reaction-diffusion PDEs are examined; the first due to the reaction term alone and the second due to the interaction of the reaction and diffusion terms, The fastest time scales of each set are responsible for the development of a low dimensional manifold, the characteristics of which depend on the set of time scales considered. The advantages and disadvantages of employing these two manifolds for the simplification of large and stiff systems of reaction-diffusion PDEs arc discussed. It is shown that the two approaches provide a non-stiff simplified system of similar accuracy. The approach based on the reaction time scales allows for a simpler construction of the simplified system, while that based on the reaction/diffusion time scales allows for a simpler time marching scheme. C1 Dipartimento Meccan & Aeronaut, I-00184 Rome, Italy. Sandia Natl Labs, Livermore, CA 94551 USA. RP Valorani, M (reprint author), Dipartimento Meccan & Aeronaut, Via Eudossiana 18, I-00184 Rome, Italy. EM dagoussi@macdagou.otenet.gr; m.valorani@dma.ing.uniroma1.it; hnnajm@ca.sandia.gov OI CRETA, Francesco/0000-0003-1923-0810; VALORANI, Mauro/0000-0002-8260-6297 NR 22 TC 26 Z9 26 U1 1 U2 4 PU INDERSCIENCE ENTERPRISES LTD PI GENEVA PA WORLD TRADE CENTER BLDG, 29 ROUTE DE PRE-BOIS, CASE POSTALE 896, CH-1215 GENEVA, SWITZERLAND SN 1468-4349 J9 PROG COMPUT FLUID DY JI Prog. Comput. Fluid Dyn. PY 2005 VL 5 IS 6 BP 316 EP 326 DI 10.1504/PCFD.2005.007064 PG 11 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA 943IC UT WOS:000230345700003 ER PT J AU Wang, L Kong, JA Ding, KH Le Toan, T Ribbes-Baillarin, F Floury, N AF Wang, L. Kong, J. A. Ding, K. H. Le Toan, T. Ribbes-Baillarin, F. Floury, N. TI Electromagetic scattering model for rice canopy based on Monte Carlo simulation SO PROGRESS IN ELECTROMAGNETICS RESEARCH-PIER LA English DT Article ID BACKSCATTERING ENHANCEMENT; BAND SAR; VEGETATION AB A scattering model for rice canopy based on Monte Carlo simulations is applied to interpret RADARSAT data and to predict the temporal response of rice growth. The model takes into account the coherent wave interactions among vegetative elements which usually occur in clusters with closely spaced elements. The model was also used to analyze the structural effect of rice fields on the scattering returns. Simulation results show a significant difference in L-band backscattering returns from rice fields with different structures, and are consistent with empirical observations from JERS-1 Campaign. Taking the ratio of HH over VV can help eliminating ambiguities in this inverse scattering problem. C1 MIT, Dept Elect Engn & Comp Sci, Cambridge, MA 02139 USA. USAF, Res Lab, AFRL SNHE, Sensors Directorate, Bedford, MA 01731 USA. Ctr Etud Spatiales BIOsphere, F-31401 Toulouse, France. Spot Image, F-31030 Toulouse 4, France. European Space Agcy, European Space Res & Technol Ctr, TEC EEP, NL-2200 AG Noordwijk, Netherlands. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wang, L (reprint author), MIT, Dept Elect Engn & Comp Sci, 77 Massachusetts Ave, Cambridge, MA 02139 USA. NR 19 TC 31 Z9 32 U1 0 U2 1 PU E M W PUBLISHING PI CAMBRIDGE PA PO BOX 425517, KENDALL SQUARE, CAMBRIDGE, MA 02142 USA SN 1559-8985 J9 PROG ELECTROMAGN RES JI Prog. Electromagn. Res. PY 2005 VL 52 BP 153 EP 171 DI 10.2528/PIER04080901 PG 19 WC Engineering, Electrical & Electronic; Physics, Applied; Telecommunications SC Engineering; Physics; Telecommunications GA 072UZ UT WOS:000239699800007 ER PT J AU Forsberg, C AF Forsberg, C TI The advanced high-temperature reactor: high-temperature fuel, liquid salt coolant, liquid-metal-reactor plant SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT 1st COE-INES International Symposium (INES-1) CY OCT 31-NOV 04, 2004 CL Tokyo, JAPAN DE high-temperature reactor; molten salt coolant; liquid salt coolant; hydrogen AB The Advanced High-Temperature Reactor is a new reactor concept that combines four existing technologies in a new way: (1) coated-particle graphite-matrix nuclear fuels (traditionally used for helium-cooled reactors), (2) Brayton power cycles, (3) passive safety systems and plant designs from liquid-metal-cooled fast reactors, and (4) low-pressure liquid-salt coolants with boiling points far above the maximum coolant temperature. The new combination of technologies enables the design of a large [2400- to 4000-MW(t)] high-temperature reactor, with reactor-coolant exit temperatures between 700 and 1000 C (depending upon goals) and passive safety systems for economic production of electricity or hydrogen. The AHTR [2400-MW(t)] capital costs have been estimated to be 49 to 61% per kilowatt (electric) relative to modular gas-cooled [600-MW(t)] and modular liquid-metal-cooled reactors [1000-MW(t)], assuming a single AHTR and multiple modular units with the same total electrical output. Because of the similar fuel, core design, and power cycles, about 70% of the required research is shared with that for high-temperature gas-cooled reactors. (C) 2005 Elsevier Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 10 TC 30 Z9 31 U1 4 U2 19 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2005 VL 47 IS 1-4 SI SI BP 32 EP 43 DI 10.1016/j.pnucene.2005.05.002 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 961PW UT WOS:000231675300006 ER PT J AU Wider, HU Carlsson, J Loewen, E AF Wider, HU Carlsson, J Loewen, E TI Renewed interest in lead cooled fast reactors SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT 1st COE-INES International Symposium (INES-1) CY OCT 31-NOV 04, 2004 CL Tokyo, JAPAN DE lead-cooled; fast reactors; LFR AB In the last few years a number of compact designs of lead-alloy cooled systems have been promoted. Moreover, in Russia a design effort was started earlier on the pure lead-cooled BREST reactor but this effort does not appear to be strongly funded any more. But now the lead cooled and compact STAR-LM reactor is promoted in the US and in the European Union there is some interest in a medium-sized lead-cooled fast reactor (LFR). It has brought some nuclear industries, a large utility, several research centers and universities together to ask the European Commission for a partial funding of design and safety efforts. A 600 MWe LFR design is proposed which would be useful for base load operation but as a fast system it could also be used for load following. Because of the possible plant simplifications and the use of pure lead, the economics of such a system should be good. Moreover, efficient fuel utilization, the burning of higher actinides and a closed fuel cycle make it a sustainable system. Whether, this larger system has the same inherent / passive safety characteristics as smaller LFRs needs to be examined. In this paper the passive emergency decay heat removal by reactor vessel air-cooling of such a larger system is investigated. Moreover an inlet blockage in a subassembly of a low power density LMR is analyzed. Furthermore, the pros and cons of lead vs. lead/bismuth coolants are discussed. (C) 2005 Published by Elsevier Ltd. C1 Commiss European Communities, Joint Res Ctr, NL-1755 ZG Petten, Netherlands. INEEL Res Ctr, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Wider, HU (reprint author), Commiss European Communities, Joint Res Ctr, Postbus 2, NL-1755 ZG Petten, Netherlands. NR 12 TC 2 Z9 2 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2005 VL 47 IS 1-4 SI SI BP 44 EP 52 DI 10.1016/j.pnucene.2005.05.003 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 961PW UT WOS:000231675300007 ER PT J AU Takahashi, H AF Takahashi, H TI Toward the 21(st) century nuclear-science technology SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT 1st COE-INES International Symposium (INES-1) CY OCT 31-NOV 04, 2004 CL Tokyo, JAPAN DE deep underground nuclear park; nanotechnology; quantum physics; weak interactions; non-proliferation AB Energy security is vital for the steady growth of the world's welfare and economy and although many novel non-nuclear energy sources are being explored, much less attention is given to nuclear energy. In developing this source, safety, environment protection, and non-proliferation are essential considerations. I have proposed establishing deep underground nuclear parks where not only energy production, but also the processing and transportation of fuel can be carried out in a well protected small area; in the near future they might be operated under international supervision to ensure non-proliferation. The quantum physics on which modern technologies such as nanotechnology, and biotechnology are based, offer a sound foundation. The mathematical and physical technologies developed in the fields of nuclear engineering will provide the fundamental educational basis for such 21(st) century science and technology. (C) 2005 Published by Elsevier Ltd. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Takahashi, H (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 9 TC 13 Z9 14 U1 3 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2005 VL 47 IS 1-4 SI SI BP 53 EP 60 DI 10.1016/j.pnucene.2005.05.004 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 961PW UT WOS:000231675300008 ER PT J AU Forsberg, C AF Forsberg, C TI Futures for hydrogen produced using nuclear energy SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT 1st COE-INES International Symposium (INES-1) CY OCT 31-NOV 04, 2004 CL Tokyo, JAPAN DE hydrogen; nuclear energy; renewables; transportation; hybrid engines AB What is the future of hydrogen (H-2) produced from nuclear energy? Assuming that economically competitive nuclear H-2 can be produced, production of H-2 may become the primary use of nuclear energy and the basis for both a nuclear-H-2 renewable (solar, wind, etc.) energy economy and a nuclear-H-2 transport system. The technical and economic bases for these conclusions are described. In a nuclear-H-2 renewable energy economy, nuclear energy is used to produce H-2 that is stored and becomes the energy-storage component of the electrical generating system. The stored H-2 replaces piles of coal and tanks of liquid fuel. Capital-intensive renewable energy sources and nuclear reactors produce electricity at their full capacity. The stored H-2 is used in fuel cells to produce the highly variable quantities of electricity needed to fill the gap between the electricity demand by the customer and the electricity generated by the rest of the electrical generating system. Hydrogen is also used to produce the liquid or gaseous transport fuels. This energy-system architecture is a consequence of the fundamental differences between the characteristics of electricity (movement of electrons) and those of H-2 (movement of atoms). Electricity can be generated, transformed, and used economically on either a small or a large scale. However, it is difficult to generate, store, and transform H-2 economically on a small scale. This distinction favors the use of large-scale nuclear systems for H-2 production. (C) 2005 Elsevier Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Forsberg, C (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 15 TC 20 Z9 20 U1 2 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2005 VL 47 IS 1-4 SI SI BP 484 EP 495 DI 10.1016/j.pnucene.2005.05.049 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 961PW UT WOS:000231675300055 ER PT J AU Loewen, EP AF Loewen, EP TI Corrosion studies in support of lead-bismuth cooled FBRs SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT 1st COE-INES International Symposium (INES-1) CY OCT 31-NOV 04, 2004 CL Tokyo, JAPAN DE lead corrosion; lead-bismuth corrosion; LBE corrosion AB The performance of structural materials in lead or lead-bismuth eutectic (LBE) systems is evaluated. The materials evaluated included several US steels (austenitic steel [316L], carbon steels [F-22, Fe-Si], ferritic/martensitic steels [HT-9 and 410]), and several experimental Fe-Si-Cr alloys that were expected to demonstrate corrosion resistance. The materials were exposed in either a dynamic corrosion cell for periods from 100 to 1,000 h at temperatures of 400, 500, 600 and 700 degrees C, depending on material and exposure location. Weight change and optical SEM or X-ray analysis of the specimen were used to characterize oxide film thickness, corrosion depth, microstructure, and composition changes. The tests conducted with stainless steels (410, 316L and HT-9) produced mass transfer of elements (e.g., Ni and Cr) into the LBE, resulting in degradation of the material. With Fe-Si alloys a Si rich layer (as SiO2) is formed on the surface during exposure to LBE from the selective dissolution of Fe. (C) 2005 Elsevier Ltd. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Loewen, EP (reprint author), Idaho Natl Engn & Environm Lab, 2525 Fremont Ave, Idaho Falls, ID 83415 USA. EM loewep@inel.gov NR 11 TC 1 Z9 1 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2005 VL 47 IS 1-4 SI SI BP 561 EP 568 DI 10.1016/j.pnucene.2005.05.075 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 961PW UT WOS:000231675300064 ER PT J AU Loewen, E AF Loewen, E TI Investigation of polonium removal systems for lead-bismuth cooled FBRs SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT 1st COE-INES International Symposium (INES-1) CY OCT 31-NOV 04, 2004 CL Tokyo, JAPAN DE polonium; lead-bismuth; lead-bismuth eutectic; alkaline extraction; heavy liquid metal; fast reactor AB The alkaline extraction method is being investigated as a method to remove polonium (Po) from a lead-bismuth (Pb-Bi) cooled reactor. Tellurium (Te) was used as a surrogate for Po for these experiments to quantify the migration from Pb-Bi to molten alkaline (NaOH). Experiments provided direct evidence that molten NaOH can effectively remove Te from Pb-Bi. A reduction of three to four orders of magnitude in the Te concentration in the metals was measured in the experiments. The experimental results also showed a higher than expected concentration of NaOH in the Pb or Pb-Bi. A comparison between experiments operated at 427 degrees C and 500 degrees C indicates that the higher operating temperature produces a higher removal rate of Te. Experiments where hot NaOH was injected into the crucible at the same temperature as the lead-bismuth eutectic (LBE) resulted in the rapid removal rate of Te and remained constant until the experiment was completed. (C) 2005 Elsevier Ltd. All rights reserved. C1 Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. RP Loewen, E (reprint author), Idaho Natl Engn Lab, 2525 Fremont Ave, Idaho Falls, ID 83415 USA. NR 20 TC 4 Z9 4 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2005 VL 47 IS 1-4 SI SI BP 586 EP 595 DI 10.1016/j.pnucene.2005.05.061 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 961PW UT WOS:000231675300067 ER PT J AU Wienke, BR AF Wienke, BR TI Transport equations in moving material - Part I: Neutrons and photons SO PROGRESS IN NUCLEAR ENERGY LA English DT Article DE neutron transport; photon transport; moving material; effective cross sections; transport approximations; relativistic dynamics; fundamental equations; frame invariance; coupled transport and hydrodynamics; diffusion ID FLUX-LIMITED DIFFUSION; CROSS-SECTIONS; ELASTIC-SCATTERING; RADIATION; HYDRODYNAMICS; SYSTEMS; NUCLEAR; FLOWS; MEDIA AB Transport equations are usually formulated against a static material background in transport applications for neutral (neutrons, photons, mesons) and charged (electrons, protons, ions) particles. When the background is moving, the equations need be modified and corrected. We discuss these modifications and corrections, in both relativistic and nonrelativistic regimes, and contrast equations across applications. Neutron, photon, electron, neutrino, and meson transport are treated in a two part series. This review collects, collates, and expands published and unpublished developments and equations for moving material transport in different particle arenas. Hopefully, such provides a useful reference and source for readers across disciplines, linking basic underlying dynamics and representations. Part I centers on neutrons and photons, and Part H deals with electrons and neutrinos, almost an historical split. While tranpsort equations for these particles share much in common, there are fundamental differences between particles that interact pointwise versus continuously, particles of zero rest mass versus nonzero rest mass, particles with relativistic energy versus nonrelativistic energy, and particles with short range versus long range. Our focuses are the fundamental equations and underlying dynamics of transport in moving backgrounds. The impacts in applications, important and legion, are detailed in the literature as cited. Accordingly, and invoking topic closure, applications are not recounted. Also, numerical techniques, developed with the emergence of supercomputing, are not treated herein. Both applications and numerical techniques are probably subjects of a separate communication Some modern transport codes dealing with moving material issues, however, are cited for reader reference. Many codes have been in existence for 25+ years, undergoing continuous updating, modification, improvement, and physical extension. For Part I, the main points of discussion and development are seen in the following Table of Contents, divided into neutron and photon moving material transport. An attempt at coverage of moving material transport with brevity is sought, and hopefully references provide details minimized, or not recounted, herein. (C) 2004 Published by Elsevier Ltd. C1 Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Wienke, BR (reprint author), Los Alamos Natl Lab, Div Appl Phys, Grp X-7, Los Alamos, NM 87545 USA. NR 86 TC 1 Z9 1 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2005 VL 46 IS 1 BP 13 EP 55 DI 10.1016/j.pnucene.2004.09.016 PG 43 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 888XB UT WOS:000226406400002 ER PT J AU Green, MA Emery, K King, DL Igari, S Warta, W AF Green, MA Emery, K King, DL Igari, S Warta, W TI Solar cell efficiency tables (version 25) SO PROGRESS IN PHOTOVOLTAICS LA English DT Article DE solar cell efficiency; photovoltaic efficiency; energy conversion efficiency AB Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since June 2004 are reviewed. Copyright (C) 2005 John Wiley Sons, Ltd. C1 Univ New S Wales, Ctr Photovolta Engn, Sydney, NSW 2052, Australia. Natl Renewable Energy Lab, Golden, CO 80401 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. AIST, RCPV, Tsukuba, Ibaraki, Japan. Fraunhofer Inst Solar Energy Syst, Dept Solar Cells Mat & Technol, D-79110 Freiburg, Germany. RP Univ New S Wales, Ctr Photovolta Engn, Sydney, NSW 2052, Australia. EM m.green@unsw.edu.au NR 47 TC 29 Z9 34 U1 4 U2 19 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1062-7995 EI 1099-159X J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD JAN PY 2005 VL 13 IS 1 BP 49 EP 54 DI 10.1002/pip.598 PG 6 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 891OX UT WOS:000226591500006 ER PT J AU Canada, S Moore, L Post, H Strachan, J AF Canada, S Moore, L Post, H Strachan, J TI Operation and maintaenance field experience for off-grid residential photovoltaic systems SO PROGRESS IN PHOTOVOLTAICS LA English DT Article DE photovoltaic systems; operation and maintenance; off-grid residential; utility photovoltaics; database; field experience AB The field performance of photovoltaic systems has been studied extensively for many applications and a number of databases exist in the United States and internationally. However, these databases focus almost exclusively on the system elecrical performance. Published information on the operation and maintenance (O&M) experience and costs for photovoltaic systems is almost nonexistent. At a time when photovoltaics is being considered as a viable option for distributed energy generation, it is critical that maintenance experience be captured to identify lifecycle costs and/or levelized energy costs for these systems, as well as to identify areas for system and component improvements. This paper addresses the data collection, analysis and results of all off-grid residential customer service program offered by the Arizona Public Service (APS) Company over a six-year period from 1997 through 2002. Standardized, packaged photovoltaic systems were offered and operated by APS through a lease arrangement with customers throughout the state of Arizona. The operation and maintenance records for these systems were carefully tracked and analyzed. The O&M costs, database development, cost drivers, lifecycle cost implications, and lessons learned are presented and discussed. Published in 2004 by John Wiley Sons, Ltd. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Arizona Publ Serv, Phoenix, AZ 85072 USA. RP Moore, L (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM lmmoore@sandia.gov NR 8 TC 5 Z9 5 U1 0 U2 4 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD JAN PY 2005 VL 13 IS 1 BP 67 EP 74 DI 10.1002/pip.573 PG 8 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 891OX UT WOS:000226591500008 ER PT B AU Silverstein, E AF Silverstein, E BE Maldacena, JM TI TASI/PiTP/ISS lectures on moduli and microphysics SO PROGRESS IN STRING THEORY: TASI 2003 LECTURE NOTES LA English DT Proceedings Paper CT Conference on Progess in String Theory CY JUN 02-27, 2003 CL Boulder, CO ID STRING WORLD SHEET; CALABI-YAU; SUPERSYMMETRY BREAKING; FIELD-THEORIES; COMPACTIFICATIONS; SUPERSTRINGS; ORBIFOLDS; FLUXES AB I review basic forces on moduli that lead to their stabilization, for example in the supercritical and KKLT models of de Sitter space in string theory, as well as an AdS(4) x S-3 x S-3 model I include which is not published elsewhere. These forces come from the classical dilaton tadpole in generic dimensionality, internal curvature, fluxes, and branes and orientifolds as well as non-perturbative effects. The resulting (A)dS solutions of string theory make detailed predictions for microphysical entropy, whose leading behavior we exhibit on the Coulomb branch of the system. Finally, I briefly review recent developments concerning the role of velocity-dependent effects in the dynamics of moduli. These lecture notes are based on material presented at various stages in the 1999 TASI, 2002 PiTP, 2003 TASI, and 2003 ISS schools. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Dept Phys, Stanford, CA 94309 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM evas@slac.stanford.edu NR 96 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 981-256-406-3 PY 2005 BP 381 EP 415 PG 35 WC Physics, Multidisciplinary; Physics, Particles & Fields SC Physics GA BDM15 UT WOS:000234252500004 ER PT B AU Silverstein, E AF Silverstein, Eva BE Maldacena, JM TI TASI/PITP/ISS LECTURES ON MODULI AND MICROPHYSICS SO PROGRESS IN STRING THEORY: TASI 2003 LECTURES NOTES LA English DT Article; Book Chapter ID STRING WORLD SHEET; CALABI-YAU; SUPERSYMMETRY BREAKING; FIELD-THEORIES; COMPACTIFICATIONS; SUPERSTRINGS; DIMENSIONS; ORBIFOLDS; FLUXES AB I review basic forces on moduli that lead to their stabilization, for example in the supercritical and KKLT models of de Sitter space in string theory, as well as an AdS(4) x S-3 x S-3 model I include which is not published elsewhere. These forces come from the classical dilaton tadpole in generic dimensionality, internal curvature, fluxes, and branes and orientifolds as well as non-perturbative effects. The resulting (A)dS solutions of string theory make detailed predictions for microphysical entropy, whose leading behavior we exhibit on the Coulomb branch of the system. Finally, I briefly review recent developments concerning the role of velocity-dependent effects in the dynamics of moduli. These lecture notes are based on material presented at various stages in the 1999 TASI, 2002 PiTP, 2003 TASI, and 2003 ISS schools. C1 [Silverstein, Eva] Stanford Univ, SLAC, Stanford, CA 94309 USA. [Silverstein, Eva] Stanford Univ, Dept Phys, Stanford, CA 94309 USA. RP Silverstein, E (reprint author), Stanford Univ, SLAC, Stanford, CA 94309 USA. NR 95 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-9-81277-510-8; 978-9-81256-406-1 PY 2005 BP 381 EP 415 D2 10.1142/9789812775108 PG 35 WC Physics, Multidisciplinary; Physics, Particles & Fields; Physics, Mathematical SC Physics GA BZF09 UT WOS:000301300800005 ER PT J AU Wang, GF Van Hove, MA Ross, PN Baskes, MI AF Wang, GF Van Hove, MA Ross, PN Baskes, MI TI Quantitative prediction of surface segregation in bimetallic Pt-M alloy nanoparticles (M = Ni, Re, Mo) SO PROGRESS IN SURFACE SCIENCE LA English DT Article DE surface segregation; modified embedded atom method; Monte Carlo method; nanoparticle; platinum; nickel; rhenium; molybdenum ID MONTE-CARLO SIMULATIONS; EMBEDDED-ATOM POTENTIALS; TRANSITION-METAL ALLOYS; 100 CRYSTAL FACES; H-2/CO MIXTURES; CATALYST NANOPARTICLES; OXYGEN REDUCTION; PARTICLES; CO; ELECTROOXIDATION AB This review addresses the issue of surface segregation in bimetallic alloy nanoparticles, which are relevant to heterogeneous catalysis, in particular for electro-catalysts of fuel cells. We describe and discuss a theoretical approach to predicting surface segregation in such nanoparticles by using the modified embedded, atom method and Monte Carlo simulations. In this manner it is possible to systematically explore the behavior of such nanoparticles as a function of component metals, composition, and particle size, among other variables. We chose to compare Pt75Ni25, Pt75Re25, and Pt80Mo20 alloys as example systems for this discussion, due to the importance of Pt in catalytic processes and its high-cost. It is assumed that the equilibrium nanoparticles of these alloys have a cubo-octahedral shape, the face-centered cubic lattice, and sizes ranging from 2.5 nm to 5.0 nm. By investigating the segregation of Pt atoms to the surfaces of the nanoparticles, we draw the following conclusions from our simulations at T = 600 K. (1) Pt75Ni25 nanoparticles form a surface-sandwich structure in which the Pt atoms are strongly enriched in the outermost and third layers while the Ni atoms are enriched in the second layer. In particular, a nearly pure Pt outermost surface layer can be achieved in those nanoparticles. (2) Equilibrium Pt75Re25 nanoparticles adopt a core-shell structure: a nearly pure Pt shell surrounding a more uniform Pt-Re core. (3) In Pt80Mo20 nanoparticles, the facets are fully occupied by Pt atoms, the Mo atoms only appear at the edges and vertices, and the Pt and Mo atoms arrange themselves in an alternating sequence along the edges and vertices. Our simulations quantitatively agree with previous experimental and theoretical results for the extended surfaces of Pt-Ni, Pt-Re, and Pt-Mo alloys. We further discuss the reasons for the different types of surface segregation found in the different alloys, and some of their implications. (c) 2005 Elsevier Ltd. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Los Alamos Natl Lab, Struct & Property Relat Grp, Los Alamos, NM 87545 USA. RP Van Hove, MA (reprint author), City Univ Hong Kong, Dept Phys & Mat Sci, Kowloon, Hong Kong, Peoples R China. EM vinhove@cityu.edu.hk RI Van Hove, Michel/A-9862-2008 OI Van Hove, Michel/0000-0002-8898-6921 NR 64 TC 77 Z9 77 U1 9 U2 82 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6816 J9 PROG SURF SCI JI Prog. Surf. Sci. PY 2005 VL 79 IS 1 BP 28 EP 45 DI 10.1016/j.progsurf.2005.09.003 PG 18 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 994TM UT WOS:000234054100003 ER PT J AU Szymanski, P Garrett-Roe, S Harris, CB AF Szymanski, P Garrett-Roe, S Harris, CB TI Time- and angle-resolved two-photon photoemission studies of electron localization and solvation at interfaces SO PROGRESS IN SURFACE SCIENCE LA English DT Review DE two-photon photoemission; image-potential states; angle-resolved photoemission; ultrafast dynamics; dielectric/metal interface; adsorbate molecular orbitals; localization; small polaron; electron solvation; spatial extent in two dimensions ID IMAGE-POTENTIAL STATES; SELF-ASSEMBLED MONOLAYERS; PUMP-PROBE SPECTROSCOPY; MOLECULAR-DYNAMICS SIMULATION; FEMTOSECOND DYNAMICS; HYDRATED ELECTRON; METAL INTERFACES; ABSORPTION SPECTROSCOPY; ULTRAFAST SOLVATION; AG(110) SURFACES AB We review recent work in the study of interfacial electronic states and electron-adsorbate interactions with time- and angle-resolved two-photon photoemission (2PPE) spectroscopy. Results for interfaces between noble-metal surfaces and organic as well as inorganic dielectric overlayers are presented. Layer structure and thickness have pronounced effects on the spatial extents, binding energies, and dynamics of image-potential states (IPS) and molecular orbitals. The transition from delocalized to localized states in the plane of the interface can also occur dynamically through electron-induced nuclear motion in the overlayer. An important example of this class of phenomenon is the formation of polaronic states from initially delocalized IPS, which occurs on sub-picosecond timescales. Dynamic energy relaxation through electron solvation by molecular dipoles, the analogue of the dynamic Stokes shift in bulk solvents, may also accompany localization on ultrafast timescales, and has become the focus of much recent experimental and theoretical interest. The interplay of a static layer structure and an evolving potential from the adsorbate creates a rich environment for interfacial electron dynamics, as evidenced by the alcohol/Ag(111), nitrile/Ag(111), and D2O/Cu(111) systems. We conclude with a discussion of recent attempts to determine the spatial extent of localization parallel to the interface for electrons following localization and solvation using experimental measurements of the photoelectron distribution in momentum space. Published by Elsevier Ltd. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, US Chem Sci Div, Berkeley, CA 94720 USA. RP Harris, CB (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM harris@socrates.berkeley.edu RI Garrett-Roe, Sean/C-6037-2011 OI Garrett-Roe, Sean/0000-0001-6199-8773 NR 141 TC 61 Z9 61 U1 10 U2 50 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6816 J9 PROG SURF SCI JI Prog. Surf. Sci. PY 2005 VL 78 IS 1 BP 1 EP 39 DI 10.1016/j.progsurf.2004.08.001 PG 39 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 910GH UT WOS:000227918300001 ER PT J AU Masuda, T Zheludev, A Sales, B Imai, S Uchinokura, K AF Masuda, T Zheludev, A Sales, B Imai, S Uchinokura, K TI Magnetic excitations in Cu2Fe2Ge4O13 SO PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT LA English DT Article; Proceedings Paper CT International Symposium on Quanturm Spin Systens CY NOV 30-DEC 03, 2004 CL Hayama, JAPAN SP Minist Educ, Culture, Sports, Sci & Technol Japan ID ANTIFERROMAGNETS; GERMANATE; CHAIN AB Magnetic excitations in the cooperative ordered state in a weakly coupled Fe chains and Cu dimers compound Cu2Fe2Ge4O13 is studied by thermal neutron scattering technique. We show that the low energy excitations up to 10 meV in wide q range are well described by spin wave theory of weakly coupled Fe chains. In higher energy range a narrow band excitation that can be associated with Cu dimers is observed at hw similar to 24 meV. Both types of excitations can be understood by treating the weak coupling between Fe chains and Cu dimers at the level of Mean Field/Random Phase Approximation. C1 Oak Ridge Natl Lab, Condensed Matter Sci Div, Oak Ridge, TN 37831 USA. Yokohama City Univ, Int Grad Sch Arts & Sci, Yokohama, Kanagawa 2360027, Japan. Univ Tokyo, Dept Adv Mat Sci, Kashiwa, Chiba 2778581, Japan. Furukawa Elect Corp Ltd, Yokohama R&D Labs, Yokohama, Kanagawa 2200073, Japan. RP Masuda, T (reprint author), Oak Ridge Natl Lab, Condensed Matter Sci Div, POB 2008, Oak Ridge, TN 37831 USA. EM tmasuda@yokohama-cu.ac.jp NR 12 TC 0 Z9 0 U1 0 U2 1 PU PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PI KYOTO PA C/O KYOTO UNIV, YUKAWA HALL, KYOTO, 606-8502, JAPAN SN 0375-9687 J9 PROG THEOR PHYS SUPP JI Prog. Theor. Phys. Suppl. PY 2005 IS 159 BP 96 EP 100 PG 5 GA 983JR UT WOS:000233228100015 ER PT J AU Hagiwara, M Regnault, LP Zheludev, A Stunault, A Metoki, N Koike, Y Kakurai, K AF Hagiwara, M Regnault, LP Zheludev, A Stunault, A Metoki, N Koike, Y Kakurai, K TI Magnetic excitation in an anisotropic bond-alternating S=1 one dimensional antiferromagnet Ni(C9D24N4)(NO2)ClO4 SO PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT LA English DT Article; Proceedings Paper CT International Symposium on Quantum Spin Systems CY NOV 30-DEC 03, 2004 CL Hayama, JAPAN SP Minist Educ, Culture, Sports, Sci & Technol Japan ID QUANTUM SPIN CHAINS; GROUND-STATE; HEISENBERG CHAIN; PHASE-DIAGRAM; DYNAMICS; FIELD AB We report the results of inelastic neutron scattering (INS) experiments on the S = 1 bond-alternating quasi-one-dimensional (ID) antiferromagnet Ni(C9D24N4)(NO2)ClO4 under magnetic fields below and above the critical field H, at which the energy gap closes. Normal field dependence of Zeeman split of the excited triplet state below H, has been observed, but the highest mode is unusually small and smears out with increasing field. This is probably explained by the highest branch buried in a magnon continuum, which was never observed in the S = 1 antiferromagnetic uniform chain. Above H-c, we observed only one excitation branch, which is completely different from the Haldane material NDMAP [A. Zheludev et al., Phys. Rev. B 68 (2003), 134438] where three gapped branches were clearly observed. C1 RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. CEA Grenoble, DRFMC SPSMS MDN, F-38054 Grenoble, France. Oak Ridge Natl Lab, Condensed Matter Sci Div, Oak Ridge, TN 37831 USA. Inst Laue Langevin, F-38042 Grenoble, France. JAERI, Adv Sci Res Ctr, Tokai, Ibaraki 3191195, Japan. RP RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. NR 18 TC 0 Z9 0 U1 0 U2 1 PU PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PI KYOTO PA C/O KYOTO UNIV, YUKAWA HALL, KYOTO, 606-8502, JAPAN SN 0375-9687 J9 PROG THEOR PHYS SUPP JI Prog. Theor. Phys. Suppl. PY 2005 IS 159 BP 101 EP 105 PG 5 GA 983JR UT WOS:000233228100016 ER PT J AU Moult, J Fidelis, K Rost, B Hubbard, T Tramontano, A AF Moult, J Fidelis, K Rost, B Hubbard, T Tramontano, A TI Critical assessment of methods of protein structure prediction (CASP) - Round 6 SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Editorial Material DE protein structure prediction; community-wide experiment; CASP ID LARGE-SCALE AB This article is an introduction to the special issue of the journal Proteins, dedicated to the sixth CASP experiment to assess the state of the art in protein structure prediction. The article describes the conduct of the experiment and the categories of prediction included, and outlines the evaluation and assessment procedures. A brief summary of progress over the decade of CASP experiments is also provided. C1 Univ Maryland, Inst Biotechnol, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. Univ Roma La Sapienza, Inst Pasteur, Fdn Cenci Bolognetti, Rome, Italy. Columbia Univ, CUBIC, Dept Biochem & Mol Biophys, New York, NY USA. RP Moult, J (reprint author), Univ Maryland, Inst Biotechnol, Ctr Adv Res Biotechnol, 9700 Gudelsky Dr, Rockville, MD 20850 USA. EM moult@umbi.umd.edu RI Hubbard, Tim/C-2567-2008; Tramontano, anna/D-5378-2009; OI Hubbard, Tim/0000-0002-1767-9318; Tramontano, anna/0000-0002-5610-3338; Moult, John/0000-0002-3012-2282 FU NIGMS NIH HHS [GM072354]; NLM NIH HHS [LM07085] NR 15 TC 99 Z9 109 U1 1 U2 4 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-3585 J9 PROTEINS JI Proteins PY 2005 VL 61 SU 7 BP 3 EP 7 DI 10.1002/prot.20716 PG 5 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 001SJ UT WOS:000234556300002 PM 16187341 ER PT J AU Kryshtafovych, A Milostan, M Szajkowski, L Daniluk, P Fidelis, K AF Kryshtafovych, A Milostan, M Szajkowski, L Daniluk, P Fidelis, K TI CASP6 data processing and automatic evaluation at the protein structure prediction center SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article; Proceedings Paper CT 6th Meeting on the Critical Assessment of Techniques for Protein Structure Prediction CY DEC 04-08, 2004 CL Gaeta, ITALY DE protein structure prediction; evaluation methods; CASP; local descriptors of protein structure AB We present a short overview of the system governing data processing and automatic evaluation of predictions in CASP6, implemented at the Livermore Protein Structure Prediction Center. The system incorporates interrelated facilities for registering participants, collecting prediction targets from crystallographers and NMR spectroscopists and making them available to the CASP6 participants, accepting predictions and providing their preliminary evaluation, and finally, storing and visualizing results. We have automatically evaluated predictions submitted to CASP6 using criteria and methods developed over the successive CASP experiments. Also, we have tested a new evaluation technique based on non-rigid-body type superpositions. Approximately the same number of predictions has been submitted to CASP6 as to all previous CASPs combined, making navigation through and understanding of the data particularly challenging. To facilitate this, we have substantially modernized all data handling procedures, including implementation of a dedicated relational database. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Fidelis, K (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. EM fidelis@llnl.gov RI Daniluk, Pawel/C-1723-2013; Milostan, Maciej/I-8408-2016 FU NLM NIH HHS [LM07085-01] NR 4 TC 12 Z9 16 U1 0 U2 6 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-3585 J9 PROTEINS JI Proteins PY 2005 VL 61 SU 7 BP 19 EP 23 DI 10.1002/prot.20718 PG 5 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 001SJ UT WOS:000234556300004 PM 16187343 ER PT J AU Eyrich, VA Kryshtafovych, A Milostan, M Fidelis, K AF Eyrich, VA Kryshtafovych, A Milostan, M Fidelis, K TI System for accepting server predictions in CASP6 SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article; Proceedings Paper CT 6th Meeting on the Critical Assessment of Techniques for Protein Structure Prediction CY DEC 04-08, 2004 CL Gaeta, ITALY DE protein structure prediction; server; CASP ID PROTEIN-STRUCTURE AB We describe the new CASP system for collecting and verifying predictions generated by servers. The system was developed to ensure reliable execution of the server assessment part of CASP, with particular emphasis on data consistency. Following the principle that predictions should not be modified by anyone but their authors and to allow a later meaningful assessment, submissions are now verified for correctness of format and contents within the strict 48 hour CASP deadlines for this type of submission. This article also provides an overview of the rules governing server participation in CASP6 and some statistics pertaining to servers in CASP6. C1 Lawrence Livermore Natl Lab, Biosci Directorate, Livermore, CA 94551 USA. Columbia Univ, CUBIC, Dept Biochem & Mol Biophys, New York, NY USA. RP Kryshtafovych, A (reprint author), Lawrence Livermore Natl Lab, Biosci Directorate, Livermore, CA 94551 USA. EM andriy@llnl.gov RI Milostan, Maciej/I-8408-2016 FU NLM NIH HHS [LM007085] NR 5 TC 1 Z9 2 U1 0 U2 2 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-3585 J9 PROTEINS JI Proteins PY 2005 VL 61 SU 7 BP 24 EP 26 DI 10.1002/prot.20719 PG 3 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 001SJ UT WOS:000234556300005 PM 16187344 ER PT J AU Kryshtafovych, A Venclovas, C Fidelis, K Moult, J AF Kryshtafovych, A Venclovas, C Fidelis, K Moult, J TI Progress over the first decade of CASP experiments SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article; Proceedings Paper CT 6th Meeting on the Critical Assessment of Techniques for Protein Structure Prediction CY DEC 04-08, 2004 CL Gaeta, ITALY DE protein structure prediction; community wide experiment; CASP ID HIDDEN MARKOV-MODELS; PROTEIN SEQUENCES; FOLD RECOGNITION; ALIGNMENT; PERFORMANCE; IMPROVEMENT; PROGRAMS AB CASP has now completed a decade of monitoring the state of the art in protein structure prediction. The quality of structure models produced in the latest experiment, CASP6, has been compared with that in earlier CASPs. Significant although modest progress has again been made in the fold recognition regime, and cumulatively, progress in this area is impressive. Models of previously unknown folds again appear to have modestly improved, and several mixed alpha/beta structures have been modeled in a topologically correct manner. Progress remains hard to detect in high sequence identity comparative modeling, but server performance in this area has moved forward. C1 Univ Maryland, Inst Biotechnol, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. Inst Biotechnol, Vilnius, Lithuania. RP Moult, J (reprint author), Univ Maryland, Inst Biotechnol, Ctr Adv Res Biotechnol, 9600 Gudelsky Dr, Rockville, MD 20850 USA. EM jmoult@tune.org OI Moult, John/0000-0002-3012-2282 FU NLM NIH HHS [LM07085-01] NR 26 TC 120 Z9 124 U1 0 U2 8 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0887-3585 J9 PROTEINS JI Proteins PY 2005 VL 61 SU 7 BP 225 EP 236 DI 10.1002/prot.20740 PG 12 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 001SJ UT WOS:000234556300026 PM 16187365 ER PT J AU Chandonia, JM Brenner, SE AF Chandonia, JM Brenner, SE TI Implications of structural genomics target selection strategies: Pfam5000, whole genome, and random approaches SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article ID HIDDEN MARKOV-MODELS; DATABASE; PREDICTION; BIOLOGY; PERSPECTIVE; PROTEOMES; EVOLUTION; PROTEINS; SEQUENCE AB Structural genomics is an international effort to determine the three-dimensional shapes of all important biological macromolecules, with a primary focus on proteins. Target proteins should be selected according to a strategy that is medically and biologically relevant, of good value, and tractable. As an option to consider, we present the "Pfam5000" strategy, which involves selecting the 5000 most important families from the Pfam database as sources for targets. We compare the Pfam5000 strategy to several other proposed strategies that would require similar numbers of targets. These strategies include complete solution of several small to moderately sized bacterial proteomes, partial coverage of the human proteome, and random selection of approximately 5000 targets from sequenced genomes. We measure the impact that successful implementation of these strategies would have upon structural interpretation of the proteins in Swiss-Prot, TrEMBL, and 131 complete proteomes (including 10 of eukaryotes) from the Proteome Analysis database at the European Bioinformatics Institute (EBI). Solving the structures of proteins from the 5000 largest Pfam families would allow accurate fold assignment for approximately 68% of all prokaryotic proteins (covering 59% of residues) and 61% of eukaryotic proteins (40% of residues). More fine-grained coverage that would allow accurate modeling of these proteins would require an order of magnitude more targets. The Pfam5000 strategy may be modified in several ways, for example, to focus on larger families, bacterial sequences, or eukaryotic sequences; as long as secondary consideration is given to large families within Pfam, coverage results vary only slightly. In contrast, focusing structural genomics on a single tractable genome would have only a limited impact in structural knowledge of other proteomes: A sig.nificant fraction (about 30-40% of the proteins and 40-60% of the residues) of each proteome is classified in small families, which may have little overlap with other species of interest. Random selection of targets from one or more genomes is similar to the Pfam5000 strategy in that proteins from larger families are more likely to be chosen, but substantial effort would be spent on small families. (C) 2004 Wiley-Liss, Inc C1 Univ Calif Berkeley, Dept Plant & Microbial Biol, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley Struct Genom Ctr, Phys Biosci Div, Berkeley, CA USA. RP Brenner, SE (reprint author), Univ Calif Berkeley, Dept Plant & Microbial Biol, 461A Koshland Hall, Berkeley, CA 94720 USA. EM brenner@compbio.berkeley.edu RI Brenner, Steven/A-8729-2008 OI Brenner, Steven/0000-0001-7559-6185 FU NHGRI NIH HHS [1-K22-HG00056]; NIGMS NIH HHS [1-P50-GM62412] NR 37 TC 40 Z9 46 U1 1 U2 4 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-3585 J9 PROTEINS JI Proteins PD JAN 1 PY 2005 VL 58 IS 1 BP 166 EP 179 DI 10.1002/prot.20298 PG 14 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 881YI UT WOS:000225905000019 PM 15521074 ER PT J AU Wang, WR Kim, R Yokota, H Kim, SH AF Wang, WR Kim, R Yokota, H Kim, SH TI Crystal structure of flavin binding to FAD synthetase of Thermotoga maritima SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article ID RAT-LIVER; PURIFICATION; PROTEIN; ADENYLYLTRANSFERASE; REVEALS; ATP C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley Struct Genom Ctr, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Kim, SH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley Struct Genom Ctr, Phys Biosci Div, Berkeley, CA 94720 USA. EM shkim@cchem.berkeley.edu FU NIGMS NIH HHS [GM 62412] NR 14 TC 25 Z9 25 U1 0 U2 1 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-3585 J9 PROTEINS JI Proteins PD JAN 1 PY 2005 VL 58 IS 1 BP 246 EP 248 DI 10.1002/prot.20207 PG 3 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 881YI UT WOS:000225905000027 PM 15468322 ER PT J AU Ahram, M Adkins, JN Auberry, DL Wunschel, DS Springer, DL AF Ahram, M Adkins, JN Auberry, DL Wunschel, DS Springer, DL TI A proteomic approach to characterize protein shedding SO PROTEOMICS LA English DT Article DE abundance; GRP78; mass spectrometry; protein shedding; Syndecan-4 ID CELL-SURFACE PROTEINS; MAMMARY EPITHELIAL-CELLS; GROWTH-FACTOR; MASS-SPECTROMETRY; MYELOMA CELLS/; FACTOR-ALPHA; MEMBRANE; IDENTIFICATION; SYNDECAN-1; ECTODOMAIN AB Shedding (i.e. proteolysis of ectodomains of membrane proteins) plays an important pathophysiological role. In order to study the feasibility of identifying shed proteins, we analyzed serum-free media of human mammary epithelial cells by mass spectrometry following induction of shedding by the phorbol ester, 4beta-phorbol 12-myristate 13-acetate (PMA). Different means of sample preparation, including biotinylation of cell surface proteins, isolation of glycosylated proteins, and preparation of crude protein fractions, were carried out to develop the optimal method of sample processing. The collected proteins were digested with trypsin and analyzed by reversed-phase capillary liquid chromatography interfaced to an ion-trap mass spectrometer. The resulting peptide spectra were interpreted using the program SEQUEST. Analyzing the sample containing the crude protein mixture without chemical modification or separation resulted in the greatest number of identifications, including putatively shed proteins. Overall, 45 membrane-associated proteins were identified including 22 that contain at least one transmembrane domain and 23 that indirectly associate with the extracellular surface of the plasma membrane. Of the 22 transmembrane proteins, 18 were identified by extracellular peptides providing strong evidence they originate from regulated proteolysis or shedding processes. We combined results from the different experiments and used a peptide count method to estimate changes in protein abundance. Using this approach, we identified two proteins, syndecan-4 and hepatoma-derived growth factor, whose abundances increased in media of cells treated with PMA. We also detected proteins whose abundances decreased after PMA treatment such as 78 kDa glucose-regulated protein and lactate dehydrogenase A. Further analysis using immunoblotting validated the abundance changes for syndecan-4 and 78 kDa glucose-regulated protein as a result of PMA treatment. These results demonstrate that tandem mass spectrometry can be used to identify shed proteins and to estimate changes in protein abundance. C1 Battelle Mem Inst, NW Natl Lab, Div Biol Sci, Richland, WA 99352 USA. Battelle Mem Inst, Pacific NW Natl Lab, NSD, Richland, WA 99352 USA. RP Springer, DL (reprint author), Battelle Mem Inst, NW Natl Lab, Div Biol Sci, Richland, WA 99352 USA. EM david.springer@pnl.gov RI Wunschel, David/F-3820-2010; Adkins, Joshua/B-9881-2013 OI Adkins, Joshua/0000-0003-0399-0700 NR 48 TC 14 Z9 14 U1 0 U2 2 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 1615-9853 J9 PROTEOMICS JI Proteomics PD JAN PY 2005 VL 5 IS 1 BP 123 EP 131 DI 10.1002/pmic.200400912 PG 9 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 894IO UT WOS:000226784800014 PM 15672459 ER PT B AU Adcock, PA Pacheco, S Brosha, E Zawodzinski, TA Uribe, FA AF Adcock, PA Pacheco, S Brosha, E Zawodzinski, TA Uribe, FA BE Murthy, M Fuller, TF VanZee, JW Gottesfeld, S TI Maximization of CO tolerance of pemfc systems using reconfigured anodes SO Proton Conducting Membrane Fuel Cells III, Proceedings SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 3rd Symposium on Proton Conducting Membrane Fuel Cells CY OCT, 2002 CL Salt Lake City, UT SP Electrochem Soc, Ind Electrolysis & Electrochem Engn Div, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys Electrochem Div ID FUEL-CELLS; OXIDATION AB The reconfigured anode (RCA) system is a small modification to the backing cloth placed on the anode side of each MEA in a PEM fuel cell stack. A catalyst layer is placed on the gas feed side of the cloth, to catalyze oxidation of CO utilizing the oxygen introduced in a small air-bleed. The purpose is to achieve a high CO-tolerance at a temperature below 100 degrees C. The development and status of this technology are described. Investigation of catalyst systems based on inexpensive transition metal oxides continues. C1 Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Adcock, PA (reprint author), Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, MST-11,MS D429, Los Alamos, NM 87545 USA. NR 14 TC 1 Z9 1 U1 1 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-455-1 J9 ELEC SOC S PY 2005 VL 2002 IS 31 BP 159 EP 173 PG 15 WC Electrochemistry SC Electrochemistry GA BCF79 UT WOS:000229108600013 ER PT B AU Bender, G Zawodzinski, TA AF Bender, G Zawodzinski, TA BE Murthy, M Fuller, TF VanZee, JW Gottesfeld, S TI Spatial distribution of the CO transient response of a PEFC SO PROTON CONDUCTING MEMBRANE FUEL CELLS III, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 3rd Symposium on Proton Conducting Membrane Fuel Cells CY OCT, 2002 CL Salt Lake City, UT SP Electrochem Soc, Ind Electrolysis & Electrochem Engn Div, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys Electrochem Div AB We report on the investigation of the current distribution of a PEFC under the influence of CO impurities in the hydrogen feed stream by application of the segmented cell system. Stepping the CO partial pressure of the anode feed stream from 0 to 100 ppm CO the current response of the cell was recorded for different stoichiometric flows. A poisoning time delay occurs along the flow path due to the anode flow rate. Also anode and cathode processes, e.g. CO turnover and oxygen mass transport limitation contribute to the time response of the cell. C1 Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Bender, G (reprint author), Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, MST-11,MS D429, Los Alamos, NM 87545 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-455-1 J9 ELEC SOC S PY 2005 VL 2002 IS 31 BP 212 EP 219 PG 8 WC Electrochemistry SC Electrochemistry GA BCF79 UT WOS:000229108600017 ER PT B AU Eickes, C Brosha, E Garzon, F Purdy, G Zelenay, P Morita, T Thompsett, D AF Eickes, C Brosha, E Garzon, F Purdy, G Zelenay, P Morita, T Thompsett, D BE Murthy, M Fuller, TF VanZee, JW Gottesfeld, S TI Electrochemical and XRD characterization of Pt-Ru blacks for DMFC anodes SO Proton Conducting Membrane Fuel Cells III, Proceedings SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 3rd Symposium on Proton Conducting Membrane Fuel Cells CY OCT, 2002 CL Salt Lake City, UT SP Electrochem Soc, Ind Electrolysis & Electrochem Engn Div, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys Electrochem Div ID METHANOL ELECTROOXIDATION; ELECTROCATALYSIS; OXIDATION; ALLOYS AB It is generally accepted that Pt-Ru alloy catalysts with an atomic Pt-to-Ru ratio of 1:1 generate the best anode performance in the direct methanol fuel cell (DMFC). However, at near-ambient cell operating temperatures, Gasteiger et al. [1] reported that a catalyst with significantly lower Ru content, similar to 10 at %, offers the highest activity towards methanol. Recently, Dinh et al. [2] demonstrated that the activity of different Pt-Ru catalysts with the same Pt-to-Ru atomic ratio in the bulk might vary depending on the actual surface composition, which is often significantly different from that in the bulk phase. In this work, we study several experimental Pt-Ru catalysts (Johnson Matthey) with Pt-to-Ru atomic ratio ranging from 9:1 to 1:2. Electrocatalytic activity of these catalysts in methanol oxidation reaction is investigated in a regular DMFC and probed using voltammetric stripping of surface CO. C1 Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM 87545 USA. RP Eickes, C (reprint author), Los Alamos Natl Lab, Mat Sci & Technol Div, MST-11, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 0 U2 3 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-455-1 J9 ELEC SOC S PY 2005 VL 2002 IS 31 BP 450 EP 467 PG 18 WC Electrochemistry SC Electrochemistry GA BCF79 UT WOS:000229108600035 ER PT B AU Pivovar, B Le Scornet, F Eickes, C Zawodzinski, C Purdy, G Wilson, M Zelenay, P AF Pivovar, B Le Scornet, F Eickes, C Zawodzinski, C Purdy, G Wilson, M Zelenay, P BE Murthy, M Fuller, TF VanZee, JW Gottesfeld, S TI A six-cell 'single-cell' stack for stack diagnostics and membrane electrode assembly evaluation SO Proton Conducting Membrane Fuel Cells III, Proceedings SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 3rd Symposium on Proton Conducting Membrane Fuel Cells CY OCT, 2002 CL Salt Lake City, UT SP Electrochem Soc, Ind Electrolysis & Electrochem Engn Div, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys Electrochem Div AB Polymer electrolyte fuel cells are promising candidates as energy conversion devices in applications from portable power to stationary applications or electric vehicles. In order to achieve practical voltage, power and energy density, stacks are employed for almost all applications. Here, we present a six-cell 'single cell' stack in which individual cells can be isolated from the stack by current carrying leads found within each of the bipolar plates. The current carrying leads allow individual cells to be isolated from the rest of the stack, so that cells can either be tested together or independently. The design of the stack, utility for specific applications, including stack diagnostics and membrane electrode assembly (MEA) testing, and some experimental results, obtained using the stack, are presented. Special focus is given in this paper to the area of direct methanol fuel cell (DMFC) stacks, however the equipment and many of the experimental results presented are appropriate for other fuel cell systems. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Pivovar, B (reprint author), Los Alamos Natl Lab, MST-11 Fuel Cells & Electrochem, Los Alamos, NM 87544 USA. NR 3 TC 1 Z9 1 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-455-1 J9 ELEC SOC S PY 2005 VL 2002 IS 31 BP 481 EP 489 PG 9 WC Electrochemistry SC Electrochemistry GA BCF79 UT WOS:000229108600037 ER PT B AU Zhu, YM Brosha, E Zelenay, P AF Zhu, YM Brosha, E Zelenay, P BE Murthy, M Fuller, TF VanZee, JW Gottesfeld, S TI Optimization of carbon-supported platinum cathode catalysts for DMFC operation SO Proton Conducting Membrane Fuel Cells III, Proceedings SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 3rd Symposium on Proton Conducting Membrane Fuel Cells CY OCT, 2002 CL Salt Lake City, UT SP Electrochem Soc, Ind Electrolysis & Electrochem Engn Div, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys Electrochem Div ID ELECTROLYTE FUEL-CELLS; LOADING ELECTRODES; METHANOL; PERFORMANCE AB In this paper, we describe performance and optimization of carbon-supported cathode catalysts at low platinum loading. We find that at a loading below 0.6 mg cm(-2) carbon-supported platinum outperforms platinum black as a DMFC cathode catalyst. A catalyst with a 1:1 volume ratio of the dry Nafion (TM) to the electronically conducting phase (platinum plus carbon support) provides the best performance in oxygen reduction reaction. Thanks to improved catalyst utilization, carbon-supported catalysts with a platinum content varying from 40 wt% to 80 wt% deliver good DMFC performance, even at relatively modest precious metal loadings investigated in this work. C1 Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM 87545 USA. RP Zhu, YM (reprint author), Los Alamos Natl Lab, Mat Sci & Technol Div, MST-11, Los Alamos, NM 87545 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-455-1 J9 ELEC SOC S PY 2005 VL 2002 IS 31 BP 490 EP 505 PG 16 WC Electrochemistry SC Electrochemistry GA BCF79 UT WOS:000229108600038 ER PT B AU Hickner, M Kim, Y McGrath, J Zelenay, P Pivovar, B AF Hickner, M Kim, Y McGrath, J Zelenay, P Pivovar, B BE Murthy, M Fuller, TF VanZee, JW Gottesfeld, S TI The effect of BPSH post treatment on DMFC performance and properties SO Proton Conducting Membrane Fuel Cells III, Proceedings SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 3rd Symposium on Proton Conducting Membrane Fuel Cells CY OCT, 2002 CL Salt Lake City, UT SP Electrochem Soc, Ind Electrolysis & Electrochem Engn Div, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys Electrochem Div ID IONOMERIC MEMBRANES; WATER AB Direct methanol fuel cells (DMFCs) are being investigated for applications ranging from milliwatt (cell phones) to kilowatt (APUs) size scales. A common pitfall for DMFCs has been the inability of the electrolyte, typically Nafion, to act as an effective methanol barrier. Methanol crossover adversely affects the cell by lowering the cell voltage due to a mixed potential at the cathode and lower fuel utilization. Improved DMFC performance was demonstrated with sulfonated poly(arylene ether sulfone) copolymer membranes (1). Another study has shown the dependence of polymer properties and morphology on the post treatment of such membranes (2). In agreement with measurements on free-standing films, the fuel cell characteristics of these membranes have been found to have a strong dependence on acidification treatment. Methanol permeability, proton conductivity, and electro-osmotic drag coefficient all were found to increase when the membranes were acidified under boiling conditions versus a low-temperature process. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Hickner, M (reprint author), Los Alamos Natl Lab, MST-11 Fuel Cells & Electrochem, Los Alamos, NM 87544 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-455-1 J9 ELEC SOC S PY 2005 VL 2002 IS 31 BP 530 EP 540 PG 11 WC Electrochemistry SC Electrochemistry GA BCF79 UT WOS:000229108600041 ER PT S AU Abdalla, M Chevassut, O Pointcheval, D AF Abdalla, M Chevassut, O Pointcheval, D BE Vaudenay, S TI One-time verifier-based encrypted key exchange SO PUBLIC KEY CRYPTOGRAPHY - PKC 2005 SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 8th International Workshop on Theory and Practice in Public Key Cryptography CY JAN 23-26, 2005 CL Les Diablerets, SWITZERLAND SP EPFL, IACR ID SECURE AB "Grid" technology enables complex interactions among computational and data resources; however, to be deployed in production computing environments "Grid" needs to implement additional security mechanisms. Recent compromises of user And server machines at Grid sites have resulted in a need for secure password-authentication key-exchange technologies. AuthA is an example of such a technology considered for standardization by the IEEE P1363.2 working group. Unfortunately in its current form AuthA does not achieve the notion of forward-secrecy in a provably-secure way nor does it allow a Grid user to log into his account using an un-trusted computer. This paper addresses this void by first proving that AuthA indeed achieves this goal, and then by modifying it in such a way that it is secure against attacks using captured user passwords or server data. C1 Ecole Normale Super, Dept Informat, F-75230 Paris, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Abdalla, M (reprint author), Ecole Normale Super, Dept Informat, F-75230 Paris, France. EM Michel.Abdalla@ens.fr; OChevassut@lbl.gov; David.Pointcheval@ens.fr RI Abdalla, Michel/H-5987-2016 OI Abdalla, Michel/0000-0002-2447-4329 NR 20 TC 39 Z9 43 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-24454-9 J9 LECT NOTES COMPUT SC PY 2005 VL 3386 BP 47 EP 64 PG 18 WC Computer Science, Theory & Methods SC Computer Science GA BBV12 UT WOS:000227984700005 ER PT J AU Barnes, L Francis, MJ Lewis, GF Linder, EV AF Barnes, L Francis, MJ Lewis, GF Linder, EV TI The influence of evolving dark energy on cosmology SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF AUSTRALIA LA English DT Review DE cosmology : theory; cosmological parameters; dark matter ID HUBBLE-SPACE-TELESCOPE; SCALAR FIELD; CONSTRAINTS; UNIVERSE; MODELS; QUINTESSENCE; CONSTANT; DENSITY AB Observational evidence indicating that the expansion of the universe is accelerating has surprised cosmologists in recent years. Cosmological models have sought to explain this acceleration by incorporating 'dark energy', of which the traditional cosmological constant is just one possible candidate. Several cosmological models involving an evolving equation of state of the dark energy have been proposed, as well as possible energy exchange to other components, such as dark matter. This paper summarizes the forms of the most prominent models and discusses their implications for cosmology and astrophysics. Finally, this paper examines the current and future observational constraints on the nature of dark energy. C1 Univ Sydney, Sch Phys, Sydney, NSW 2006, Australia. Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. RP Lewis, GF (reprint author), Univ Sydney, Sch Phys, Sydney, NSW 2006, Australia. EM gfl@physics.usyd.edu.au RI Lewis, Geraint/F-9069-2015; OI Lewis, Geraint/0000-0003-3081-9319; Barnes, Luke/0000-0002-0016-9485 NR 53 TC 10 Z9 10 U1 0 U2 2 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 1323-3580 EI 1448-6083 J9 PUBL ASTRON SOC AUST JI Publ. Astron. Soc. Aust. PY 2005 VL 22 IS 4 BP 315 EP 325 DI 10.1071/AS05031 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 029GZ UT WOS:000236550400005 ER PT S AU Fleming, GT AF Fleming, GT BE Borici, A Frommer, A Joo, B Kennedy, A Pendleton, B TI What can Lattice QCD theorists learn from NMR spectroscopists? SO QCD and Numerical Analysis III SE LECTURE NOTES IN COMPUTATIONAL SCIENCE AND ENGINEERING LA English DT Proceedings Paper CT 3rd International Workshop on Numerical Analysis and Lattice QCD CY JUN 30-JUL 04, 2003 CL Univ Edinburgh, Edinburgh, SCOTLAND HO Univ Edinburgh ID TOTAL LEAST-SQUARES; SINGULAR-VALUE DECOMPOSITION; ALGORITHM AB The Lattice QCD (LQCD) community has occasionally gone through periods of self-examination of its data analysis methods and compared them with methods used in other disciplines [22, 16, 18]. This process has shown that the techniques widely used elsewhere may also be useful in analyzing LQCD data. It seems that we are in such a period now with many groups trying what are generally called Bayesian methods such as Maximal Entropy (MEM) or constrained fitting [19, 15, 1, 7, 5, and many others]. In these proceedings we will attempt to apply this process to a comparison of data modeling techniques used in LQCD and NMR Spectroscopy to see if there are methods which may also be useful when applied to LQCD data. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Fleming, GT (reprint author), Jefferson Lab, 1200 Jefferson Ave, Newport News, VA 23606 USA. NR 28 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 1439-7358 BN 3-540-21257-4 J9 LECT NOTES COMP SCI PY 2005 VL 47 BP 143 EP 152 PG 10 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA BDB92 UT WOS:000232435500014 ER PT S AU Kumar, P Mehta, A Krstic, P Barnes, MD AF Kumar, P Mehta, A Krstic, P Barnes, MD BE Huffaker, DL Bhattacharya, PK TI Oriented semiconducting polymer nanostructures: Photon statistics and far-field dipole interactions SO Quantum Dots, Nanoparticles, and Nonoclusters II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Quantum Dots, Nanoparticles, and Nanoclusters II CY JAN 24-25, 2005 CL San Jose, CA SP SPIE DE conjugated polymers; nanostructures; single-photon sources; dipole-dipole coupling ID ROOM-TEMPERATURE; QUANTUM CRYPTOGRAPHY; SPONTANEOUS EMISSION; SINGLE MOLECULES; FLUORESCENCE AB We summarize recent experiments probing photon statistics and collective interactions amongst individual z-oriented semiconducting polymer nanostructures. We show that oriented nanostructures from single molecules of a conducting polymer act as highly robust room-temperature single-photon sources. These results suggest the feasibility of an inexpensive "push-button" technology for polymer-based single-photon sources in photonic-based quantum information processing applications. In addition, fluorescence lifetime measurements on pairs of uniformly z-oriented polymer nanostructures that reveal far-field coherent coupling persisting on a distance scale of several optical wavelengths. Farfield photonic coupling between pairs of oriented luminescent polymer nanostructures is manifested by an oscillatory modulation in the fluorescence decay rate as a function of interparticle distance (both enhancement and inhibition of spontaneous luminescence relative to isolated particles), that results from modification of the vacuum field at the position of the probe dipole by the presence of the second radiating dipole. C1 Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Barnes, MD (reprint author), Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. NR 24 TC 0 Z9 0 U1 2 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5708-6 J9 P SOC PHOTO-OPT INS PY 2005 VL 5734 BP 13 EP 18 DI 10.1117/12.597143 PG 6 WC Optics SC Optics GA BCK30 UT WOS:000229697800002 ER PT S AU Strasburg, JD Harper, WW AF Strasburg, JD Harper, WW BE Razeghi, M Brown, GJ TI Challenges in infrared remote sensing SO Quantum Sensing and Nanophotonic Devices II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Quantum Sensing and Nanophotonic Devices II CY JAN 23-27, 2005 CL San Jose, CA SP SPIE DE remote sensing; LIDAR; chemical detection AB During the last several years, Pacific Northwest National Lab has developed a remote sensing system designed to detect trace chemicals present in the atmosphere. Using Frequency Modulated Differential Absorption LIDAR (FM DIAL) techniques chemical signatures have been observed over pathlengths ranging from several hundred meters to several kilometers. Throughout the development process, we have encountered many challenges. Some of these have been overcome but others will require more novel solutions. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Strasburg, JD (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd, Richland, WA 99352 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5706-X J9 P SOC PHOTO-OPT INS PY 2005 VL 5732 BP 144 EP 151 DI 10.1117/12.598281 PG 8 WC Instruments & Instrumentation; Optics; Spectroscopy SC Instruments & Instrumentation; Optics; Spectroscopy GA BCF41 UT WOS:000229036500015 ER PT S AU Padilla, WJ Yen, TJ Fang, N Vier, DC Smith, DR Pendry, JB Zhang, X Basov, DN AF Padilla, WJ Yen, TJ Fang, N Vier, DC Smith, DR Pendry, JB Zhang, X Basov, DN BE Razeghi, M Brown, GJ TI Infrared spectroscopy and ellipsometry of magnetic metamaterials SO QUANTUM SENSING AND NANOPHOTONIC DEVICES II SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Quantum Sensing and Nanophotonic Devices II CY JAN 23-27, 2005 CL San Jose, CA SP SPIE DE THz; meta material; left handed; negative index; bianisotropy; chiral; ellipsometry ID NEGATIVE REFRACTION; CHIRAL MEDIA; LIGHT AB We present S and P polarized measurements of artificial bianisotropic magnetic metamaterials with resonant behavior at infrared frequencies. These metamaterials consist of an array of micron sized (similar to 40 mu m) copper rings fabricated upon a quartz substrate. Simulation of the reflectance is obtained through a combination of electromagnetic eigenmode simulation and Jones matrix analysis, and we find excellent agreement with the experimental data. It is shown that although the artificial magnetic materials do indeed exhibit a magnetic response, care must be taken to avoid an undesirable electric dipole resonance, due to lack of reflection symmetry in one orientation. The effects of bianisotropy on negative index are detailed and shown to be beneficial for certain configurations of the material parameters. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Padilla, WJ (reprint author), Los Alamos Natl Lab, MS K764 MST 10, Los Alamos, NM 87545 USA. RI Fang, Nicholas/A-5856-2008 OI Fang, Nicholas/0000-0001-5713-629X NR 17 TC 3 Z9 3 U1 1 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5706-X J9 PROC SPIE PY 2005 VL 5732 BP 460 EP 469 DI 10.1117/12.581787 PG 10 WC Instruments & Instrumentation; Optics; Spectroscopy SC Instruments & Instrumentation; Optics; Spectroscopy GA BCF41 UT WOS:000229036500045 ER PT S AU Awes, TC AF Awes, TC BE Brambilla, N Devoto, A Prosperi, GM DAlesio, U Maung, K Serci, S TI Direct photons as a probe of deconfinement in heavy ion collisions SO QUARK CONFINEMENT AND THE HADRON SPECTRUM VI SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th Conference on Quark Confinement and the Hadron Spectrum CY SEP 21-25, 2004 CL Villasimius, ITALY SP Inst Nazl Fis Nucl, Univ Degli Studi Milano, Dipartmento Fis, Univ Degli Studi Cagilari, Dipartmento Fis, Sezione INFN Cagiiari, Reg Sardegna ID HADRON PHASE-TRANSITION; QUARK-GLUON PLASMA; S+AU COLLISIONS; NUCLEAR COLLISIONS; SINGLE-PHOTON; 200-GEV/C; EMISSION; MOMENTUM; SPECTRA; GEV/C AB We discuss the results and conclusions to be drawn from direct photon measurements in ultra-relativistic heavy ion collisions at the CERN SPS and at RHIC. The direct photon results provide upper limits on the initial temperature of the hot-dense matter produced in central A+A collisions which imply that the system exists in a state with a large number of degrees of freedom, as expected for a deconfined Quark Gluon Plasma. At RHIC energies the preliminary direct photon results indicate that the observed hadron suppression is a final state effect, as expected due to parton energy loss in the produced matter. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37830 USA. EM awes@bnl.gov NR 36 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0241-8 J9 AIP CONF PROC PY 2005 VL 756 BP 10 EP 19 PG 10 WC Physics, Nuclear SC Physics GA BCF67 UT WOS:000229070700002 ER PT S AU Creutz, M AF Creutz, M BE Brambilla, N Devoto, A Prosperi, GM DAlesio, U Maung, K Serci, S TI Spontaneous CP violation and quark mass ambiguities SO QUARK CONFINEMENT AND THE HADRON SPECTRUM VI SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th Conference on Quark Confinement and the Hadron Spectrum CY SEP 21-25, 2004 CL Villasimius, ITALY SP Inst Nazl Fis Nucl, Univ Degli Studi Milano, Dipartmento Fis, Univ Degli Studi Cagilari, Dipartmento Fis, Sezione INFN Cagiiari, Reg Sardegna ID CHIRAL SYMMETRY; LATTICE; U(1) AB I explore the regions of quark masses where CP will be spontaneously broken in the strong interactions. The boundaries of these regions are controlled by the chiral anomaly, which manifests itself in ambiguities in the definition of non-degenerate quark masses. In particular, the concept of a single massless quark is ill defined. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM creutz@bnl.gov NR 19 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0241-8 J9 AIP CONF PROC PY 2005 VL 756 BP 143 EP 151 PG 9 WC Physics, Nuclear SC Physics GA BCF67 UT WOS:000229070700015 ER PT S AU Sugihara, T AF Sugihara, T BE Brambilla, N Devoto, A Prosperi, GM DAlesio, U Maung, K Serci, S TI Matrix product variational formulation for lattice gauge theory SO Quark Confinement and the Hadron Spectrum VI SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 6th Conference on Quark Confinement and the Hadron Spectrum CY SEP 21-25, 2004 CL Villasimius, ITALY SP Inst Nazl Fis Nucl, Univ Degli Studi Milano, Dipartmento Fis, Univ Degli Studi Cagilari, Dipartmento Fis, Sezione INFN Cagiiari, Reg Sardegna ID QUANTUM RENORMALIZATION-GROUPS AB For hamiltonian lattice gauge theory, we introduce the matrix product anzats inspired from density matrix renormalization, group. In this method, wavefunction of the target state is assumed to be a product of finite matrices. As a result, the energy becomes a simple function of the matrices, which can be evaluated using a computer. The minimum of the energy function corresponds to the vacuum state. We show that the S = 1/2 Heisenberg chain model are well described with the ansatz. The method is also applied to the two-dimensional S = 1/2 Heisenberg and U(1) plaquette chain models. C1 Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. RP Sugihara, T (reprint author), Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. NR 14 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0241-8 J9 AIP CONF PROC PY 2005 VL 756 BP 305 EP 308 PG 4 WC Physics, Nuclear SC Physics GA BCF67 UT WOS:000229070700049 ER PT S AU Bodwin, GT Lee, J Sinclair, DK AF Bodwin, GT Lee, J Sinclair, DK BE Brambilla, N Devoto, A Prosperi, GM DAlesio, U Maung, K Serci, S TI Spin correlations and velocity-scaling in NRQCD matrix elements SO Quark Confinement and the Hadron Spectrum VI SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 6th Conference on Quark Confinement and the Hadron Spectrum CY SEP 21-25, 2004 CL Villasimius, ITALY SP Inst Nazl Fis Nucl, Univ Degli Studi Milano, Dipartmento Fis, Univ Degli Studi Cagilari, Dipartmento Fis, Sezione INFN Cagiiari, Reg Sardegna ID LATTICE QCD; HEAVY QUARKONIUM; SPECTROSCOPY AB We compute spin-dependent matrix elements for decays of S-wave quarkonia in lattice NRQCD. They appear to be in approximate agreement with the velocity-scaling rules of NRQCD. C1 Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA. RP Bodwin, GT (reprint author), Argonne Natl Lab, HEP Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 16 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0241-8 J9 AIP CONF PROC PY 2005 VL 756 BP 384 EP 386 PG 3 WC Physics, Nuclear SC Physics GA BCF67 UT WOS:000229070700075 ER PT S AU Leitch, MJ AF Leitch, MJ BE Brambilla, N Devoto, A Prosperi, GM DAlesio, U Maung, K Serci, S TI Overview of charm production - J/psi's and open charm SO Quark Confinement and the Hadron Spectrum VI SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 6th Conference on Quark Confinement and the Hadron Spectrum CY SEP 21-25, 2004 CL Villasimius, ITALY SP Inst Nazl Fis Nucl, Univ Degli Studi Milano, Dipartmento Fis, Univ Degli Studi Cagilari, Dipartmento Fis, Sezione INFN Cagiiari, Reg Sardegna DE heavy quarks; J/psi; psi ' and gamma; nuclear effects; shadowing ID GLUON DISTRIBUTION-FUNCTIONS; LARGE NUCLEI; SUPPRESSION; POLARIZATION; COLLISIONS; QUARK AB Heavy quark production provides a sensitive window for the study of the gluon structure of nucleons and its modification in nuclei. It also provides a very important means of studying the hot-dense conditions created in high-energy collisions of heavy nuclei and a critical probe to look for de-confinement in this hot-dense matter. I will review, from an experimental point of view, the physics issues as seen in current experimental results for charm production and point out the remaining puzzles. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Leitch, MJ (reprint author), Los Alamos Natl Lab, P-25 MS H846, Los Alamos, NM 87544 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0241-8 J9 AIP CONF PROC PY 2005 VL 756 BP 393 EP 395 PG 3 WC Physics, Nuclear SC Physics GA BCF67 UT WOS:000229070700078 ER PT S AU Creutz, M AF Creutz, M BE Brambilla, N Devoto, A Prosperi, GM DAlesio, U Maung, K Serci, S TI The invariant measure for SU(N) SO Quark Confinement and the Hadron Spectrum VI SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 6th Conference on Quark Confinement and the Hadron Spectrum CY SEP 21-25, 2004 CL Villasimius, ITALY SP Inst Nazl Fis Nucl, Univ Degli Studi Milano, Dipartmento Fis, Univ Degli Studi Cagilari, Dipartmento Fis, Sezione INFN Cagiiari, Reg Sardegna AB I present a simple recursive relation between the invariant measure for integration over SU(N) and the product of the measure for a sphere S(2N-1) times the measure for SU(N-1). I also discuss the periodicity factor that appears in non-trivial mappings of S(2N-1) into SU(N). C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Creutz, M (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0241-8 J9 AIP CONF PROC PY 2005 VL 756 BP 466 EP 466 PG 1 WC Physics, Nuclear SC Physics GA BCF67 UT WOS:000229070700103 ER PT B AU Petelin, M Caryotakis, G Postoenko, Y Scheitrum, G Turchin, I AF Petelin, M Caryotakis, G Postoenko, Y Scheitrum, G Turchin, I BE Hirshfield, JL Petelin, MI TI Quasi-optical multiplexers for space communication and radar with synthesized frequency band SO Quasi-Optical Control of Intense Microwave Transmission SE NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Quasi-Optical Control of Intense Microwave Transmission CY FEB 17-20, 2004 CL Nizhny Novgorod, RUSSIA SP NATO, Russian Acad Sci, Inst Appl Phys DE communication; radar; signal processing; optimized algorithms; range resolution AB In radar and communication systems, a broad frequency band can be synthesized of several narrow ones. At millimeter and sub-millimeter waves, the multiplexer for combining narrow-banded channels can be composed of quasi-optical mirror cavities. However, mutual adjustment of the cavities for radar and communication should be quite different. In the radar with synthesized frequency band, an adaptive spectrum regularization algorithm provides automatic shrinkage of the range resolution scale with the target approaching. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Petelin, M (reprint author), Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RI Turchin, Ilya/E-3863-2014 OI Turchin, Ilya/0000-0002-8471-7361 NR 12 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-3636-1 J9 NATO SCI SER II MATH PY 2005 VL 203 BP 185 EP 198 PG 14 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BEA88 UT WOS:000236503900015 ER PT S AU Chew, GF AF Chew, GF BE Elitzur, A Dolev, S Kolenda, N TI Event-based quantum theory SO Quo Vadis Quantum Mechanics? SE FRONTIERS COLLECTION LA English DT Proceedings Paper CT Workshop on Philosophy of Quantum Theory CY OCT, 2002 CL Philadelphia, PA C1 Lawrence Berkeley Lab, Theoret Phys Grp, Div Phys, Berkeley, CA 94720 USA. RP Chew, GF (reprint author), Lawrence Berkeley Lab, Theoret Phys Grp, Div Phys, Berkeley, CA 94720 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 1612-3018 BN 3-540-22188-3 J9 FRONTIERS COLL PY 2005 BP 351 EP 370 DI 10.1007/3-540-26669-0_18 PG 20 WC Physics, Multidisciplinary SC Physics GA BCB99 UT WOS:000228552400018 ER PT S AU Stapp, HP AF Stapp, HP BE Elitzur, A Dolev, S Kolenda, N TI Quantum theory of the human person SO Quo Vadis Quantum Mechanics? SE FRONTIERS COLLECTION LA English DT Proceedings Paper CT Workshop on Philosophy of Quantum Theory CY OCT, 2002 CL Philadelphia, PA C1 Lawrence Berkeley Lab, Berkeley, CA 94270 USA. RP Stapp, HP (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94270 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 1612-3018 BN 3-540-22188-3 J9 FRONTIERS COLL PY 2005 BP 397 EP 404 DI 10.1007/3-540-26669-0_20 PG 8 WC Physics, Multidisciplinary SC Physics GA BCB99 UT WOS:000228552400020 ER PT S AU Doerry, AW Dubbert, DF Thompson, M Gutierrez, VD AF Doerry, AW Dubbert, DF Thompson, M Gutierrez, VD BE Trebits, RN Kurtz, JL TI A portfolio of fine resolution Ka-band SAR images: part I SO Radar Sensor Technology 1X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Radar Sensor Technology IX CY MAR 31, 2005 CL Orlando, FL SP SPIE DE SAR; radar; image; fine resolution AB Sandia National Laboratories designs and builds Synthetic Aperture Radar (SAR) systems capable of forming high-quality exceptionally fine resolution images. During the spring of 2004 a series of test flights were completed with a Ka-band testbed SAR on Sandia's DeHavilland DHC-6 Twin Otter aircraft. A large data set was collected including real-time fine-resolution images of a variety of target scenes. This paper offers a sampling of high quality images representative of the output of Sandia's Ka-band testbed radar with resolutions as fine as 4 inches. Images will be annotated with descriptions of collection geometries and other relevant image parameters. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Doerry, AW (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 1 TC 4 Z9 4 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5773-6 J9 P SOC PHOTO-OPT INS PY 2005 VL 5788 BP 13 EP 24 DI 10.1117/12.598796 PG 12 WC Instruments & Instrumentation; Imaging Science & Photographic Technology SC Instruments & Instrumentation; Imaging Science & Photographic Technology GA BCR79 UT WOS:000230961200002 ER PT S AU Doerry, AW AF Doerry, AW BE Trebits, RN Kurtz, JL TI Autofocus correction of SAR images exhibiting excessive residual migration SO RADAR SENSOR TECHNOLOGY 1X SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Radar Sensor Technology IX CY MAR 31, 2005 CL Orlando, FL SP SPIE DE SAR; radar; image; autofocus AB Relatively small motion measurement errors manifest themselves principally as a phase error in Synthetic Aperture Radar (SAR) complex data samples, and if large enough become observable as a smearing, blurring, or other degradation in the image. The phase error function can be measured and then deconvolved from the original data to compensate for the presumed motion error, ultimately resulting in a well-focused image. Techniques that do this are termed "autofocus" algorithms. A very popular autofocus algorithm is the Phase Gradient Autofocus (PGA) algorithm. The nearly universal, and typically reasonable, assumption is that the motion errors are less than the range resolution of the radar, allowing solely a phase correction to suffice. Very large relative motion measurement errors manifest themselves as an unexpected additional shifting or migration of target locations beyond any deterministic migration during the course of the synthetic aperture. Degradation in images from data exhibiting errors of this magnitude are substantial, often rendering the image completely useless. When residual range migration due to either real or apparent motion errors exceeds the range resolution, conventional autofocus algorithms fail. Excessive residual migration is increasingly encountered as resolutions become finer, less expensive inertial sensors are used, and operating ranges become longer (due to atmospheric phenomena). A new migration-correction autofocus algorithm has been developed that estimates the excessive residual migration and applies phase and frequency corrections to properly focus the image. This overcomes the conventional constraint that motion errors not exceed the SAR range resolution. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Doerry, AW (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. EM awdoerr@sandia.gov NR 6 TC 6 Z9 6 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5773-6 J9 PROC SPIE PY 2005 VL 5788 BP 34 EP 45 DI 10.1117/12.603903 PG 12 WC Instruments & Instrumentation; Imaging Science & Photographic Technology SC Instruments & Instrumentation; Imaging Science & Photographic Technology GA BCR79 UT WOS:000230961200004 ER PT S AU Doerry, AW Dubbert, DF Thompson, M Gutierrez, VD AF Doerry, AW Dubbert, DF Thompson, M Gutierrez, VD BE Trebits, RN Kurtz, JL TI Portfolio of fine resolution Ka-band SAR images: part II SO Radar Sensor Technology 1X SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Radar Sensor Technology IX CY MAR 31, 2005 CL Orlando, FL SP SPIE DE SAR; radar; image; fine resolution AB Sandia National Laboratories designs and builds Synthetic Aperture Radar (SAR) systems capable of forming high-quality exceptionally fine resolution images. During the spring of 2004 a series of test flights were completed with a Ka-band testbed SAR on Sandia's DeHavilland DHC-6 Twin Otter aircraft. A large data set was collected including real-time fine-resolution images of a variety of target scenes. This paper offers a sampling of high quality images representative of the output of Sandia's Ka-band testbed radar with resolutions as fine as 4 inches. Images will be annotated with descriptions of collection geometries and other relevant image parameters. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Doerry, AW (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 1 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5773-6 J9 P SOC PHOTO-OPT INS PY 2005 VL 5788 BP 185 EP 196 DI 10.1117/12.598799 PG 12 WC Instruments & Instrumentation; Imaging Science & Photographic Technology SC Instruments & Instrumentation; Imaging Science & Photographic Technology GA BCR79 UT WOS:000230961200020 ER PT J AU Gallmeier, FX Ferguson, PD Popova, II Iverson, EB AF Gallmeier, FX Ferguson, PD Popova, II Iverson, EB TI The Spallation Neutron Source (SNS) project: A fertile ground for radiation protection and shielding challenges SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB The Spallation Neutron Source facility presently under construction in the USA consists of a front end, a linac, an accumulator ring, a target station and a neutron instrument hall, producing pulsed neutron beams driven by a proton beam of 1 GeV energy and 1.4 NW power with a repetition rate of 60 Hz. The layout of the facility and the radiation protection and shielding concept of the facility is laid out in numerous examples in a walk from the proton beam generation to the neutron utilisation. C1 Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37831 USA. RP Gallmeier, FX (reprint author), Oak Ridge Natl Lab, Spallat Neutron Source, POB 2008,MS 6474, Oak Ridge, TN 37831 USA. EM fzgallmeier@ornl.gov OI Iverson, Erik /0000-0002-7920-705X; Popova, Irina/0000-0001-9965-9902; Ferguson, Phillip/0000-0002-7661-4223 NR 26 TC 2 Z9 2 U1 0 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 23 EP 32 DI 10.1093/rpd/nci140 PN 1 PG 10 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600005 PM 16381678 ER PT J AU Chang, GS Ambrosek, RG AF Chang, GS Ambrosek, RG TI Hardening neutron spectrum for advanced actinide transmutation experiments in the ATR SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB The most effective method for transmuting long-lived isotopes contained in spent nuclear fuel into shorter-lived fission products is in a fast neutron spectrum reactor. In the absence of a fast test reactor in the United States, initial irradiation testing of candidate fuels can be performed in a thermal test reactor that has been modified to produce a test region with a hardened neutron spectrum. Such a test facility, with a spectrum similar but somewhat softer than that of the liquid-metal fast breeder reactor (LMFBR), has been constructed in the INEEL's Advanced Test Reactor (ATR). The radial fission power distribution of the actinide fuel pin, which is an important parameter in fission gas release modelling, needs to be accurately predicted and the hardened neutron spectrum in the ATR and the LMFBR fast neutron spectrum is compared. The comparison analyses in this study are performed using MCWO, a well-developed tool that couples the Monte Carlo transport code MCNP with the isotope depletion and build-up code ORIGEN-2. MCWO analysis yields time-dependent and neutronspectrum-dependent minor actinide and Pu concentrations and detailed radial fission power profile calculations for a typical fast reactor (LMFBR) neutron spectrum and the hardened neutron spectrum test region in the ATR. The MCWO-calculated results indicate that the cadmium basket used in the advanced fuel test assembly in the ATR can effectively depress the linear heat generation rate in the experimental fuels and harden the neutron spectrum in the test region. C1 Idaho Natl Engn & Enivornm Lab, Idaho Falls, ID 83415 USA. RP Chang, GS (reprint author), Idaho Natl Engn & Enivornm Lab, POB 1625, Idaho Falls, ID 83415 USA. EM gsc@inel.gov NR 11 TC 1 Z9 1 U1 0 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 63 EP 68 DI 10.1093/rpd/nci167 PN 1 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600010 PM 16381683 ER PT J AU Hendricks, JS Finch, JP Choi, C AF Hendricks, JS Finch, JP Choi, C TI Calculation of eigenfunction fluxes in nuclear systems SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc ID CONVERGENCE AB A new Monte Carlo method is being developed to calculate eigenfunction fluxes in critical or near-critical nuclear systems. The correct estimation of fluxes is essential for radiation protection and shielding near these systems, in addition to isotope production, isotope depletion, nuclear criticality and other applications. The proposed method applies to Monte Carlo criticality eigenvalue calculations in which the fission sites in one generation are used as fission sources in subsequent generations. The usual Monte Carlo power iteration method for such problems often calculates fluxes (eigenfunctions) that are inaccurate and very different in symmetric parts of a problem geometry. The proposed method calculates flux distributions by estimating an approximate fission matrix. The way the fission matrix is estimated and used differs from other recent works. Preliminary results are promising. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Purdue Univ, Sch Nucl Engn, W Lafayette, IN 47906 USA. RP Hendricks, JS (reprint author), Los Alamos Natl Lab, D-5, Los Alamos, NM 87545 USA. EM hendricks@lanl.gov NR 10 TC 0 Z9 0 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 69 EP 72 DI 10.1093/rpd/nci190 PN 1 PG 4 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600011 PM 16381684 ER PT J AU Wilson, WB Perry, RT Charlton, WS Parish, TA Shores, EF AF Wilson, WB Perry, RT Charlton, WS Parish, TA Shores, EF TI Sources: A code for calculating (alpha,n), spontaneous fission, and delayed neutron sources and spectra SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc ID LIGHT-ELEMENTS; BOMBARDMENT; YIELDS AB SOURCES is a computer code that determines neutron production rates and spectra from (a,n) reactions, spontaneous fission and delayed neutron emission owing to the decay of radionuclides in homogeneous media, interface problems and three-region interface problems. The code is also capable of calculating the neutron production rates due to (a,n) reactions induced by a monoenergetic beam of alpha particles incident on a slab of target material. The (a,n) spectra are calculated using an assumed isotropic angular distribution in the centre-of-mass system with a library of 107 nuclide decay alpha-particle spectra, 24, sets of measured and/or evaluated (a,n) cross sections and product nuclide level branching fractions, and functional alpha particle stopping cross sections for Z < 106. Spontaneous fission sources and spectra are calculated with evaluated half-life, spontaneous fission branching and Wart spectrum parameters for 44 actinides. The delayed neutron spectra are taken from an evaluated library of 105 precursors. The code outputs the magnitude and spectra of the resultant neutron sources. It also provides an analysis of the contributions to that source by each nuclide in the problem. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Texas A&M Univ, Dept Nucl Engn, College Stn, TX 77843 USA. RP Shores, EF (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM eshores@lanl.gov NR 34 TC 10 Z9 10 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 117 EP 121 DI 10.1093/rpd/nci260 PN 1 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600022 PM 16381695 ER PT J AU Leal, LC Derrien, H Larson, NM Alpan, A AF Leal, LC Derrien, H Larson, NM Alpan, A TI Covariance and sensitivity data generation at ORNL SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB Covariance data are required to assess uncertainties in design parameters in several nuclear applications. The error estimation of calculated quantities relies on the nuclear data uncertainty information available in the basic nuclear data libraries, such as the US Evaluated Nuclear Data Library, ENDF/B. The uncertainty files in the ENDF/B library are obtained from the analysis of experimental data and are stored as variance and covariance data. In this paper we address the generation of covariance data in the resonance region done with the computer code SAMMY. SAMMY is used in the evaluation of the experimental data in the resolved and unresolved resonance energy regions. The data fitting of cross sections is based on the generalised least-squares formalism (Bayesian theory) together with the resonance formalism described by R-matrix theory. Two approaches are used in SAMMY for the generation of resonance parameter covariance data. In the evaluation process SAMMY generates a set of resonance parameters that fit the data, and, it provides the resonance parameter covariances. For resonance parameter evaluations where there are no resonance parameter covariance data available, the alternative is to use an approach called the 'retroactive' resonance parameter covariance generation. In this paper, we describe the application of the retroactive covariance generation approach for the gadolinium isotopes. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Leal, LC (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. EM leallc@ornl.gov NR 5 TC 5 Z9 5 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 133 EP 135 DI 10.1093/rpd/nci126 PN 1 PG 3 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600026 PM 16381699 ER PT J AU Ferguson, PD Gallmeier, FX Iverson, EB Popova, II AF Ferguson, PD Gallmeier, FX Iverson, EB Popova, II TI Target station shielding issues at the spallation neutron source SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB Recent spallation neutron source shielding activities in support of the neutron beam shutters and the hot cell walls are presented. Existing neutron beam shutters can be replaced with concrete at low power or with concrete and steel at similar to 500 kW of beam power. Potential voids in the hot cell walls are analysed to determine the impact on dose rates as a function of void size. A change in the type of shielding work is noted as the project moved from the early design stages as a 'green field' site to the current stage as a construction project nearing completion, where issues to be addressed are approaching retrofit-type analyses. C1 Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37830 USA. RP Ferguson, PD (reprint author), Oak Ridge Natl Lab, Spallat Neutron Source, 701 Scarboro Rd, Oak Ridge, TN 37830 USA. EM fergusonpd@ornl.gov OI Popova, Irina/0000-0001-9965-9902; Ferguson, Phillip/0000-0002-7661-4223; Iverson, Erik /0000-0002-7920-705X NR 6 TC 0 Z9 0 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 170 EP 175 DI 10.1093/nci182 PN 1 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600034 PM 16381707 ER PT J AU Rokni, SH Khater, H Liu, JC Mao, S Vincke, H AF Rokni, SH Khater, H Liu, JC Mao, S Vincke, H TI Calculations of neutron and photon source terms and attenuation profiles for the generic design of the SPEAR3 storage ring shield SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB The FLUKA Monte Carlo particle generation and transport code was used to calculate shielding requirements for the 3 GeV, 500 mA SPEAR3 storage ring at the Stanford Synchrotron Radiation Laboratory. The photon and neutron dose equivalent source term data were simulated for a 3 GeV electron beam interacting with two typical target/shielding geometries in the ring. The targets simulated are a rectangular block of 0.7 cm thick copper and a 5 cm thick iron block, both tilted at 1 degrees relative to the beam direction. Attenuation profiles for neutrons and photons in concrete and lead as a function of angle at different shield thicknesses were calculated. The first, second and equilibrium attenuation lengths of photons and neutrons in the shield materials are derived from the attenuation profiles. The source term data and the attenuation lengths were then used to evaluate the shielding requirements for the ratchet walls of all front-ends of the SPEAR3 storage ring. C1 Stanford Linear Accelerator Ctr, Radiat Protect Dept, Stanford, CA 94309 USA. RP Rokni, SH (reprint author), Stanford Linear Accelerator Ctr, Radiat Protect Dept, POB 4349, Stanford, CA 94309 USA. EM rokni@slac.stanford.edu NR 12 TC 0 Z9 0 U1 1 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 200 EP 206 DI 10.1093/rpd/nci254 PN 1 PG 7 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600039 PM 16381712 ER PT J AU Derrien, H Leal, LC Guber, KH Larson, NM AF Derrien, H Leal, LC Guber, KH Larson, NM TI Evaluation of silicon neutron resonance parameters in the thermal to 1800 keV energy range SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB Because silicon is a major constituent of concrete and soil, neutron and gamma ray information on silicon is important for reactor shielding and criticality safety calculations. Therefore, much effort was put into the ENDF/B-VI evaluation for the three stable isotopes of silicon. The neutron capture cross section of natural silicon was recently measured at the Oak Ridge Electron Linear Accelerator (ORELA) in the energy range 1-700 keV. Using the ENDF/B-VI evaluation for initial values, a new evaluation of the resonance parameters was performed by adding the results of the ORELA capture measurements to the experimental database. The computer code SAMMY was used for the analysis of the experimental data; the new version of SAMMY allows accurate calculations of the self-shielding and multiple scattering effects in the capture measurements. The accuracy of the radiative capture widths of the resonances was improved by this analysis. Accurate values of the s-, P- and d-wave neutron strength functions were also obtained. Although the resonance capture component of the present evaluation is 2-3 times smaller than that in ENDF/B-VI, the total capture cross section is much larger, at least for energies > 250 keV, because the direct capture component contributes values of the same order of magnitude as the resonance component. The direct component was not taken into account in the ENDF/B-VI evaluation and was calculated for the first time in the present evaluation. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, POB 2008,MS 6171, Oak Ridge, TN 37831 USA. EM derrienh@ornl.gov NR 13 TC 0 Z9 0 U1 0 U2 2 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 EI 1742-3406 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 227 EP 231 DI 10.1093/rpd/nci117 PN 1 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600044 PM 16381717 ER PT J AU Devine, RT AF Devine, RT TI Monte Carlo modelling of a simple accident dosemeter SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB A simple dosemeter made of a sulphur tablet, bare and cadmium-covered indium foils and a cadmium-covered copper foil has been modelled using MCNP5. Studies of the model without phantom or other confounding factors have shown that the cross sections and fluence-to-dose factors generated by the Monte Carlo method agree with those generated by analytic expressions for the high energy component. In this study, a comparison of the effect of location on phantoms and an extension to low and intermediate energies is done. The activities expected from exposure to four critical assemblies on phantom is calculated and compared with observations. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Devine, RT (reprint author), Los Alamos Natl Lab, HSR-4,POB 1663, Los Alamos, NM 87545 USA. EM devine_r@lanl.gov NR 7 TC 0 Z9 0 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 276 EP 278 DI 10.1093/rpd/nci277 PN 1 PG 3 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600055 PM 16381728 ER PT J AU Wooten, HO Dudziak, DJ Hertel, NE Kornreich, DE AF Wooten, HO Dudziak, DJ Hertel, NE Kornreich, DE TI A time-dependent dose model for glovebox processing of fissile material SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB A new modeling system for high-intensity neutral particle radiation fields is presented. The code PANDEMONIUM calculates external effective dose rates from neutrons and photons produced at specific locations within an industrial-size plutonium processing facility. The new version of PANDEMONIUM introduces time-dependent neutronics for source multiplication coupled with transient source and detector positions. The code is designed to provide quick and acceptably accurate total effective dose estimates for scenarios and facilities for which conventional methods prove to be too impractical or costly to model. The energy range of the code has also been extended to include the effects of prompt-fission photons. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Georgia Inst Technol, Neely Nucl Res Ctr, Atlanta, GA 30332 USA. RP Wooten, HO (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM hasani@lanl.gov NR 11 TC 1 Z9 1 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 350 EP 356 DI 10.1093/rpd/nci081 PN 1 PG 7 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600072 PM 16381745 ER PT J AU Popova, II AF Popova, II TI MCNPX vs. DORT for SNS shielding design studies SO RADIATION PROTECTION DOSIMETRY LA English DT Article; Proceedings Paper CT 10th International Conference on Radiation Shielding (ICRS-10)/13th ANS Topical Meeting on Radiation Protection and Shielding (RPS 2004) CY MAY 09-14, 2004 CL Funchal, PORTUGAL SP Amer Nucl Soc AB Radiation transport occurs through the 18 in long access way adjacent to the Spallation Neutron Source accelerator tunnel and the 2.2 in thick massive shielding door which closes the access way. A variety of typical materials for accelerator shielding, such as concrete and steel, were used for construction of the door to study radiation penetration. A comparison was carried out using both Monte Carlo (code MCNPX) and discrete ordinates (code DORT) methods. The beam losses during the accelerator operation are the sources for the radiation calculations. Analyses show that the results from the two methods are in good agreement. C1 Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37830 USA. RP Popova, II (reprint author), Oak Ridge Natl Lab, Spallat Neutron Source, 701 Scarboro Rd, Oak Ridge, TN 37830 USA. EM popovai@ornl.gov OI Popova, Irina/0000-0001-9965-9902 NR 7 TC 2 Z9 2 U1 0 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 115 IS 1-4 SI SI BP 559 EP 563 DI 10.1093/rpd/nci217 PN 1 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 010SQ UT WOS:000235218600113 PM 16381785 ER PT J AU Olsher, RH Frymire, A Gregoire, T AF Olsher, RH Frymire, A Gregoire, T TI An environmental-level, real-time, pulsed photon dosemeter SO RADIATION PROTECTION DOSIMETRY LA English DT Article AB Radiation sources producing short pulses of photon radiation are widespread. Such sources include electron linear accelerators and field emission impulse generators. It is often desirable to measure leakage and skyshine radiation for these sources in real time and at environmental levels as low as 0.02 mu Sv per pulse. This note provides an overview of the design and performance of a commercial, real-time, pulsed photon dosemeter (PPD) capable of single-pulse dose measurements over the range from 0.02 to 20 mu Sv. The PPD may also be operated in a multiple-pulse mode that integrates the dose from a train of pulses over a 3 s period. A pulse repetition rate of up to 300 Hz is accommodated. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. TSA Syst Ltd, Longmont, CO 80504 USA. RP Olsher, RH (reprint author), Los Alamos Natl Lab, Mail Stop J573,POB 1663, Los Alamos, NM 87545 USA. EM dick@lanl.gov NR 2 TC 0 Z9 0 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0144-8420 J9 RADIAT PROT DOSIM JI Radiat. Prot. Dosim. PY 2005 VL 113 IS 1 BP 112 EP 114 DI 10.1093/rpd/nch431 PG 3 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 918YN UT WOS:000228585600014 PM 15769803 ER PT J AU Morris, GM Coderre, JA Micca, PL Nawrocky, MM Hopewell, JW Miura, M AF Morris, GM Coderre, JA Micca, PL Nawrocky, MM Hopewell, JW Miura, M TI Porphyrin-mediated boron neutron capture therapy: A preclinical evaluation of the response of the oral mucosa SO RADIATION RESEARCH LA English DT Article ID MOUSE TONGUE EPITHELIUM; FRACTIONATED IRRADIATIONS; GLIOBLASTOMA-MULTIFORME; P-BORONOPHENYLALANINE; REPOPULATION KINETICS; RADIATION RESPONSE; BRAIN-TUMORS; NECK-CANCER; HEAD; TRIALS AB Preclinical studies are in progress to determine the potential of boron neutron capture therapy (BNCT) for the treatment of carcinomas of the head and neck. Recently, it has been demonstrated that various boronated porphyrins can target a variety of tumor types. Of the porphyrins evaluated so far, copper tetracarboranylphenyl porphyrin (CuTCPH) is potentially a strong candidate for clinical use. In the present investigation, the response of the oral mucosa to CuTCPH-mediated boron neutron capture (BNC) irradiation was assessed using the ventral surface of the tongue of adult male Fischer 344 rats, a standard rodent model. CuTCPH was administered by intravenous infusion, at a dose of 200 mg/kg body weight, over a 48-h period. Three days after the end of the administration of CuTCPH, biodistribution studies indicated very low levels of boron (<2 mug/g) in the blood. Levels of boron in tongue tissue were 39.0 +/- 3.8 mug/g at this time. This was the time selected for irradiation with single doses of thermal neutrons from the Brookhaven Medical Research Reactor. The estimated level of boron-10 in the oral mucosa was used in the calculation of the physical radiation doses from the B-10(n,alpha)Li-7 reaction. This differs from the approach using the present generation of clinical boron carriers, where boron levels in blood at the time of irradiation are used for this calculation. Dose-response curves for the incidence of mucosal ulceration were fitted using probit analysis, and the doses required to produce a 50% incidence of the effect (ED50 +/- SE) were calculated. Analysis of the dose-effect data for CuTCPH-mediated BNC irradiation, compared with those for X rays and thermal neutrons alone, gave a compound biological effectiveness (CBE) factor of similar to0.04. This very low CBE factor would suggest that there was relatively low accumulation of boron in the key target epithelial stem cells of the oral mucosa. As a consequence, with low levels of boron (<2 mug/g) in the blood, the response of the oral mucosa to CuTCPH-mediated BNCT will be governed primarily by the radiation effects of the thermal neutron beam and not from the boron neutron capture reaction [B-10(n,alpha)Li-7]. (C) 2005 by Radiation Research Society. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. MIT, Dept Nucl Engn, Boston, MA USA. Churchill Hosp, Dept Clin Oncol, Oxford OX3 7LJ, England. RP Morris, GM (reprint author), Brookhaven Natl Lab, Dept Med, Bldg 490, Upton, NY 11973 USA. NR 31 TC 3 Z9 3 U1 1 U2 2 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JAN PY 2005 VL 163 IS 1 BP 72 EP 78 DI 10.1667/RR3272 PG 7 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 882QV UT WOS:000225954300007 PM 15606309 ER PT S AU Myra, JR D'Ippolito, DA Russell, DA Berry, LA Jaeger, EF Carter, MD AF Myra, JR D'Ippolito, DA Russell, DA Berry, LA Jaeger, EF Carter, MD BE Wukitch, SJ Bonoli, PT TI Nonlinear ICRF-plasma interactions SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE nonlinear; ion cyclotron range; sheath; ponderomotive; parametric; flow; shear ID ION BERNSTEIN WAVES; SCRAPE-OFF-LAYER; FRASCATI TOKAMAK UPGRADE; INDUCED POLOIDAL FLOW; CYCLOTRON RANGE; EDGE PLASMA; RADIOFREQUENCY WAVES; IMPURITY PRODUCTION; POWER DEPOSITION; FARADAY SCREEN AB The well developed linear theory of ICRF (including FW, HHFW and IBW) interactions with plasma has enjoyed considerable success in describing antenna coupling and wave propagation, and provides a well-known framework for calculating power absorption, current drive, etc. In some situations, less well studied nonlinear effects are of interest, such as flow drive, ponderomotive forces, rf sheaths, parametric decay and related interactions with the edge plasma. Standard ICRF codes have begun to integrate this physics to achieve improved modeling capabilities. This paper concentrates on basic rf-plasma-interaction physics with illustrative applications to tokamaks. For FW antennas, the parallel electric field near launching structures is known to drive rf-sheaths which can give rise to convective cells, interaction with plasma "blobs", impurity production, and edge power dissipation. In addition to sheaths, IBW waves in the edge plasma are subject to strong ponderomotive effects and parametric decay. In the core plasma, slow waves can sometimes induce nonlinear effects. Mechanisms by which these waves can influence the radial electric field and its shear are summarized, and related to the general (reactive-ponderomotive and dissipative) force on a plasma from rf waves. It is argued that there are significant opportunities now for new predictive capabilities by advances in integrated simulation. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Myra, JR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 70 TC 5 Z9 5 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 3 EP 14 PG 12 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700001 ER PT S AU Jaeger, EF Berry, LA Harvey, RW Myra, JR Dumont, RJ Phillips, CK Smithe, DN Batchelor, DB Bonoli, PT Carter, MD D'Azevedo, E D'Ippolito, DA Wright, JC AF Jaeger, EF Berry, LA Harvey, RW Myra, JR Dumont, RJ Phillips, CK Smithe, DN Batchelor, DB Bonoli, PT Carter, MD D'Azevedo, E D'Ippolito, DA Wright, JC BE Wukitch, SJ Bonoli, PT TI Self-consistent full-wave/Fokker-Planck calculations for ion cyclotron heating in non-Maxwellian plasmas SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE full-wave; ICRF heating; Fokker-Planck; plasma simulation ID ABSORPTION; WAVE AB Self-consistent solutions for the wave electric field and particle distribution function are calculated for ion cyclotron heating in non-Maxwellian plasmas. The all-orders wave solver AORSA is generalized to treat non-thermal velocity distributions arising from fusion reactions, neutral beam injection, and wave driven diffusion in velocity space. Quasi-linear diffusion coefficients are derived directly from the wave electric fields and used to calculate velocity distribution functions with the CQL3D Fokker-Planck code. Self-consistent results are obtained by iterating the full-wave and Fokker-Planck solutions. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Jaeger, EF (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 11 TC 1 Z9 1 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 23 EP 30 PG 8 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700003 ER PT S AU Berry, LA Jaeger, EF AF Berry, LA Jaeger, EF CA SciDAC RF-Plasma Interactions BE Wukitch, SJ Bonoli, PT TI Positive quasi linear operator formulation SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE quasi linear; Fokker Planck; RF plasma interactions ID WAVE AB Expressions for the RF quasi-linear operator are biquadratic sums over the Fourier modes (or FLR equivalent) that describe the RF electric field with a kernel that is a function of the two wave vectors, (k) over right arrow (L) and (k) over right arrow (R), in the sum. As a result of either an implicit or explicit average over field lines or flux surfaces, this kernel only depends on one parallel wave vector, conventionally k(R)(0) When k(0) is an independent component of the representation for E, the sums are demonstrably positive. However, except for closed field line systems, k(0) is dependent on the local direction of the equilibrium magnetic field, and, empirically, the absorbed energy and quasi-linear diffusion coefficients are observed to have negative features. We have formally introduced an independent k(0) sum by Fourier transforming the RF electric field, (assuming straight field lines) using a field-line-length coordinate. The resulting expression is positive. We have modeled this approach by calculating the quasi linear operator for "modes" with fixed k(0). We form these modes by discretizing k(0) and then assigning all of the Fourier components with k(0) that fall within a given k(0) bin to that k(0) mode. Results will be shown as a function of the number of bins. Future work will involve implementing the expressions derived from the Fourier transform and evaluating the dependence on field line length. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Berry, LA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 42 EP 45 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700006 ER PT S AU Wilson, JR Bernabei, S Biewer, T Diem, S Hosea, J LeBlanc, B Phillips, CK Ryan, P Swain, DW AF Wilson, JR Bernabei, S Biewer, T Diem, S Hosea, J LeBlanc, B Phillips, CK Ryan, P Swain, DW BE Wukitch, SJ Bonoli, PT TI Parametric decay during HHFW on NSTX SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE RF heating; parametric decay; spherical torus ID SPHERICAL TORUS EXPERIMENT; ION BERNSTEIN WAVES; HARMONIC FAST WAVES; PLASMA; EXCITATION AB High Harmonic Fast Wave (HHFW) heating experiments on NSTX have been observed to be accompanied by significant edge ion heating (T-i >> T-e). This heating is found to be anisotropic with T-perp > T-par. Simultaneously, coherent oscillations have been detected with an edge Langmuir probe. The oscillations are consistent with parametric decay of the incident fast wave (omega > 13 omega) into ion Bernstein waves and an unobserved ion-cyclotron quasi-mode. The observation of anisotropic heating is consistent with Bernstein wave damping and the Bernstein waves should completely damp in the plasma periphery as they propagate toward a cyclotron harmonic resonance. The number of daughter waves is found to increase with if power and to increase as the incident wave's toroidal wavelength increases. The frequencies of the daughter wave are separated by the edge ion cyclotron frequency. Theoretical calculations of the threshold for this decay in uniform plasma indicate an extremely small value of incident power should be required to drive the instability. While such decays are commonly observed at lower harmonics in conventional ICRF heating scenarios they usually do not involve the loss of significant wave power from the pump wave. On NSTX an estimate of the power loss can be found by calculating the minimum power required to support the edge ion heating (presumed to come from the decay Bernstein wave). This calculation indicates at least 20-30% of the incident rf power ends up as decay waves. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Wilson, JR (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 13 TC 16 Z9 16 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 66 EP 73 PG 8 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700012 ER PT S AU Hosea, JC Bernabei, S Biewer, T LeBlanc, B Phillips, CK Wilson, JR Stutman, D Ryan, P Swain, DW AF Hosea, JC Bernabei, S Biewer, T LeBlanc, B Phillips, CK Wilson, JR Stutman, D Ryan, P Swain, DW BE Wukitch, SJ Bonoli, PT TI Electron energy confinement for HHFW heating and current drive phasing on NSTX SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE RF heating; electron energy and confinement time; spherical torus ID PLASMAS AB Thomson scattering laser pulses are synchronized relative to modulated HHFW power to permit evaluation of the electron energy confinement time during and following HHFW pulses for both heating and current drive antenna phasing. Profile changes resulting from instabilities require that the total electron stored energy, evaluated by integrating the midplane electron pressure Pe(R) over the magnetic surfaces prescribed by EFIT analysis, be used to derive the electron energy confinement time. Core confinement is reduced during a sawtooth instability but, although the electron energy is distributed outward by the sawtooth, the bulk electron energy confinement time is essentially unaffected. The radial deposition of energy into the electrons is noticeably more peaked for current drive phasing (longer wavelength excitation) relative to that for heating phasing (shorter wavelength excitation) as is expected theoretically. However, the power delivered to the core plasma is reduced considerably for the current drive phasing, indicating that surface/peripheral damping processes play a more important role for this case. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Hosea, JC (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Stutman, Dan/P-4048-2015 NR 6 TC 6 Z9 6 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 82 EP 85 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700014 ER PT S AU LeBlanc, BP Bell, RE Bernabei, S Biewer, TM Hosea, JC Wilson, JR AF LeBlanc, BP Bell, RE Bernabei, S Biewer, TM Hosea, JC Wilson, JR BE Wukitch, SJ Bonoli, PT TI Investigation of HHFW and NBI combined heating in NSTX SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE NSTX HHFWNBI ID SPHERICAL TORUS EXPERIMENT; HARMONIC FAST-WAVE; PLASMAS AB A series of experiments was conducted to investigate the combined utilization of HHFW and NBI auxiliary heating in NSTX plasmas. A modest increase of the total stored energy coincident with a near doubling of the neutron production rate is observed when NBI beating is added to HHFW in L-mode plasmas. An increase in the core electron temperature is also observed. On the other hand, essentially no stored energy augmentation nor neutron production rate enhancement is observed when applying HHFW during the "H" phase of NBI driven H-mode plasmas. Spectroscopic measurements of the edge carbon line radiation indicate an unpredicted ion temperature increase, suggesting that edge effects are reducing the amount of HHFW power reaching the plasma core. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP LeBlanc, BP (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 86 EP 89 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700015 ER PT S AU Zweben, SJ Terry, JL Bonoli, P Budny, R Chang, CS Fiore, C Hughes, J Lin, Y Perkins, R Porkolab, M Schilling, G Wukitch, S AF Zweben, SJ Terry, JL Bonoli, P Budny, R Chang, CS Fiore, C Hughes, J Lin, Y Perkins, R Porkolab, M Schilling, G Wukitch, S CA Alcator C-Mod Team BE Wukitch, SJ Bonoli, PT TI Edge minority heating experiment in Alcator C-Mod SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE lCRH; H-mode; Alcator C-Mod; minority heating AB An attempt was made to control global plasma confinement in the Alcator C-Mod tokamak by applying ICRH heating power to the plasma edge in order to deliberately create a minority ion tail loss. In theory, an edge fast ion loss could modify the edge electric field and so stabilize the edge turbulence, which might then reduce the H-mode power threshold or improve the H-mode barrier. However, the experimental result was that edge minority heating resulted in no improvement in the edge plasma parameters or global stored energy, at least at power levels of P-RF <= 5.5 MW. Some analysis of these results is presented and some ideas for improvement are discussed. C1 Princeton Plasma Phys Lab, Princeton, NJ 08540 USA. RP Zweben, SJ (reprint author), Princeton Plasma Phys Lab, Princeton, NJ 08540 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 118 EP 121 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700021 ER PT S AU Kaufman, AN Brizard, AJ Tracy, ER AF Kaufman, AN Brizard, AJ Tracy, ER BE Wukitch, SJ Bonoli, PT TI Triplicate Budden resonance in the presence of sheared flow SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE mode conversion; shear flow; tokamak ID LINEAR-MODE-CONVERSION AB In order to reduce turbulent transport in tokamaks, several groups have introduced a layer of toroidal or poloidal sheared flow. We study the influence of such a layer on the process of linear wave resonance, also known as mode conversion. Because of the local Doppler shift caused by the flow, the dispersion relations of waves are modified, and a single Budden resonance may be replaced by a triple resonance. The occurence of such triplication depends on the layer's parameters: its location, maximum flow speed, and radial width. We use a standard one-dimensional slab model, with cold-plasma response in the ion-gyrofrequency range, with the example of conversion of a magnetosonic wave to ion-hybrid waves. When triplication occurs, wave energy is converted at three locations instead of one. This possibility must be taken into account in designing conversion scenarios for heating, for current-drive, or for flow-drive. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Kaufman, AN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. OI Brizard, Alain/0000-0002-0192-6273 NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 146 EP 149 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700027 ER PT S AU Goulding, RH Baity, FW Durodie, F Fadnek, A Freudenberg, KD Hosea, JC Loesser, GD Nelson, BE Nightingale, M Rasmussen, DA Sparks, DO Walton, R AF Goulding, RH Baity, FW Durodie, F Fadnek, A Freudenberg, KD Hosea, JC Loesser, GD Nelson, BE Nightingale, M Rasmussen, DA Sparks, DO Walton, R BE Wukitch, SJ Bonoli, PT TI Status of the JET ITER-like antenna high-power prototype test program SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc AB Previous tests of a High Power Prototype (HPP) comprising one quadrant of the JET ITER-Like ICRF Antenna have indicated the need for some design modifications in order to achieve 10 s pulses coupling the full design power (7.1 MW) into the reference plasma load (R'= 4 Omega/m). These modifications have now been made to the HPP, as well as to the design of the ITER-Like Antenna itself. In particular, maximum current densities have been reduced or otherwise accommodated in key areas. New current straps for the HPP have been fabricated from stereo-lithography-based investment castings. Design modifications to the antenna enclosure have also been implemented. This work has been materially assisted through the use of CST Microwave Studio (MWS), a commercially available 3-D electromagnetic modeling package. Essentially the full engineering CAD model of the HIPP current straps and antenna enclosure has been ex-ported from ProE to MWS. Computed current density profiles have been introduced into an ANSYS thermal model. These activities will be discussed, as well as the current status of the HPP test program. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Goulding, RH (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Goulding, Richard/C-5982-2016 OI Goulding, Richard/0000-0002-1776-7983 NR 3 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 194 EP 197 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700036 ER PT S AU Schilling, G Wukitch, SJ Lin, Y Parisot, A Porkolab, M AF Schilling, G Wukitch, SJ Lin, Y Parisot, A Porkolab, M CA Alcator C-Mod Team BE Wukitch, SJ Bonoli, PT TI Initial operation of the Alcator C-Mod WRY antennas with high-Z metal antenna guards SO RADIO FREQUENCY POWER IN PLASMAS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc AB The Alcator C-Mod ICRF antennas have been operated with BN antenna guards since 2000. This modification had followed the observation that metallic impurities in the plasma increased with increasing ICRF power. Systematic improvements to the antenna structure have allowed the launched power to be raised to the 6 MW level, with good heating efficiency and few deleterious effects on the plasma. BN is inherently fragile, and disruption mechanical shocks have resulted in fracturing of the antenna tiles, exposing the supporting metal structure. Since the antennas are now electrically in reasonable shape, and one of C-Mod's goals is to study the behavior of plasmas with all-metal plasma facing components, it was decided to replace the BN tiles with molybdenum. High power operation was resumed in March, 2005, and the behavior of the antennas during the present run campaign will be reported. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 206 EP 209 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700039 ER PT S AU Carter, AD D'Ippolito, DA Myra, JR Russell, DA AF Carter, AD D'Ippolito, DA Myra, JR Russell, DA BE Wukitch, SJ Bonoli, PT TI Fusion antenna analysis using the modular oak ridge RF integration code (MORRFIC) SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc AB Nonlinear and small scale effects occur in the RF near-field region of fusion antennas, including sheaths, ponderomotive effects, and gas build-up to self-generate plasma. Integrated modules in MORRFIC can estimate the importance of, and interplay between, these various effects. Modules include a linear RF Maxwell solver with plasma variations across and along field lines. Solutions from this module can be used to estimate ponderomotive effects, sheath driving terms, and collisional dissipation. Other modules can be iterated with these solutions to study plasma transport. Transport models include SOLT, which models the effect of RF fields on turbulent radial plasma transport, and a weakly-ionized two-dimensional model of collisional transport in RF self-generated plasma. The geometry allows azimuthally symmetric perfectly conducting boundary conditions and complex dielectrics, including a local plasma dielectric tensor. 3-D antenna structures can be modeled using Fourier analysis. A sheath mask is implemented to allow different non-linear sheath models to be included, and diagnostics are available to estimate non-linear effects. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Carter, AD (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 218 EP 221 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700042 ER PT S AU Taylor, G Bers, A Bigelow, TS Carter, MD Caughman, JB Decker, J Diem, S Efthimion, PC Ershov, NM Fredd, E Harvey, RW Hosea, J Jaeger, F Preinhaelter, J Ram, AK Rasmussen, DA Smirnov, AP Wilgen, JB Wilson, JR AF Taylor, G Bers, A Bigelow, TS Carter, MD Caughman, JB Decker, J Diem, S Efthimion, PC Ershov, NM Fredd, E Harvey, RW Hosea, J Jaeger, F Preinhaelter, J Ram, AK Rasmussen, DA Smirnov, AP Wilgen, JB Wilson, JR BE Wukitch, SJ Bonoli, PT TI Electron Bernstein wave research on the national spherical torus experiment SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE spherical tokamaks; electron Bernstein waves ID CURRENT DRIVE; PLASMAS; BETA AB Off-axis electron Bernstein wave current drive (EBWCD) may be critical for sustaining non-inductive high P NSTX plasmas. Modeling results predict that the similar to 100 kA of off-axis current needed to stabilize a solenoid-free high P NSTX plasma could be generated by by 3 MW of 28 GHz EBW power. Synergy with the bootstrap current may enhance CD efficiency by similar to 10%. EBW radiometry measurements on NSTX support coupling to EBWs by launching elliptically polarized electromagnetic waves oblique to the confining magnetic field. Plans are being developed to implement a 1 MW, 28 GHz proof-of-principle EBWCD system to test the EBW coupling, heating and CD physics at high rf power densities on NSTX. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Taylor, G (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Decker, Joan/B-7779-2010; Ershov, Nikolay/E-4162-2013; Smirnov, Alexander /A-4886-2014; Preinhaelter, Josef/H-1394-2014; Caughman, John/R-4889-2016 OI Decker, Joan/0000-0003-0220-2653; Caughman, John/0000-0002-0609-1164 NR 20 TC 0 Z9 0 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 337 EP 340 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700066 ER PT S AU Ryan, PM Carter, MD Hoffman, DJ AF Ryan, PM Carter, MD Hoffman, DJ BE Wukitch, SJ Bonoli, PT TI RF power coupling and plasma transport effects in magnetized capacitive discharges SO Radio Frequency Power in Plasmas SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 16th Topical Conference on Radio Frequency Power in Plasmas CY APR 11-13, 2005 CL Park City, UT SP Amer Phys Soc DE capacitively-coupled plasma sources; plasma etch tools AB Static magnetic fields have been used to expand the operational envelope, increase power efficiency, and control processing parameters in capacitively-coupled radio frequency plasma discharges. A simple physical model has been developed to investigate the roles of the plasma dielectric tenser and plasma transport in determining the ion flux spatial profile along a wafer surface over a range of plasma density, neutral pressure and magnetic field strength and orientation. The model has been incorporated into the MORRFIC code[1] and calculations have been made for a capacitively-coupled 300-mm etch tool operating at frequencies greater than 100 MHz. A Lieberman sheath model[2] show effects that can occur when the sheath voltages are made to be consistent with the driven RF fields in the collisional unmagnefized limit; other sheath models will also be considered. A two-dimensional transport model accounts for magnetized cross-field diffusion. Results isolate magnetic field effects that are caused by modification of the plasma dielectric from transport effects that are caused by the reduced electron mobility perpendicular to the magnetic field. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Ryan, PM (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37830 USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0276-0 J9 AIP CONF PROC PY 2005 VL 787 BP 437 EP 440 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BDC31 UT WOS:000232634700085 ER PT J AU Guilderson, TP Cole, JE Southon, JR AF Guilderson, TP Cole, JE Southon, JR TI Pre-bomb Delta C-14 variability and the suess effect in Cariaco Basin surface waters as recorded in hermatypic corals SO RADIOCARBON LA English DT Article ID TROPICAL ATLANTIC; RADIOCARBON; OCEAN; AGE; VENTILATION; CALIBRATION; CYCLE; C-14; AMS AB The Delta(14)C content of surface waters in and around the Cariaco Basin was reconstructed from radiocarbon measurements on sub-annually sampled coral skeletal material. During the late 1930s to early 1940s, surface waters within and outside of the Cariaco Basin were similar. Within the Cariaeo Basin at Islas Tortugas, coral Delta(14)C averages -51.9 +/- 3.3 parts per thousand. Corals collected outside of the basin at Boca de Medio and Los Testigos have Delta(14)C values of -53.4 +/- 3.3 parts per thousand and -54.3 +/- 2.6, respectively. Additional C-14 analyses on the Isla Tortugas coral document an similar to 11 parts per thousand decrease between similar to 1905 (-40.9 +/- 4.5 parts per thousand) and similar to 1940. The implied Suess effect trend (-3 parts per thousand/decade) is nearly as large as that observed in the atmosphere over the same time period. If we assume that there is little to no fossil fuel (CO2)-C-14 signature in Cariaco surface waters in similar to 1905, the waters have an equivalent reservoir age of similar to 312 yr. C1 Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. Univ Calif Santa Cruz, Dept Ocean Sci, Santa Cruz, CA 94056 USA. Univ Arizona, Dept Geosci, Tucson, AZ 85721 USA. RP Guilderson, TP (reprint author), Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. EM tguilderson@llnl.gov NR 18 TC 10 Z9 12 U1 0 U2 4 PU UNIV ARIZONA DEPT GEOSCIENCES PI TUCSON PA RADIOCARBON 4717 E FORT LOWELL RD, TUCSON, AZ 85712 USA SN 0033-8222 J9 RADIOCARBON JI Radiocarbon PY 2005 VL 47 IS 1 BP 57 EP 65 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 956ZI UT WOS:000231338500008 ER PT J AU Angulo, RJ de Souza, MC Reimer, PJ Sasaoka, SK AF Angulo, RJ de Souza, MC Reimer, PJ Sasaoka, SK TI Reservoir effect of the southern and southeastern Brazilian coast SO RADIOCARBON LA English DT Article ID RADIOCARBON AGE CALIBRATION; MARINE SAMPLES AB A regional marine reservoir correction (Delta R) of 33 +/- 24 C-14 yr for southern Brazil was obtained from 6 marine shell samples collected in the states of Santa Catarina and Parana. This work also presents a Delta R estimation of 8 +/- 17 C-14 yr for the southern and southeastern Brazilian coast from the states of Rio de Janeiro to Santa Catarina, obtained by including 7 ages published in previous works. The high variability of R in modem and Holocene samples from the Brazilian coast is also discussed. C1 Univ Fed Parana, Dept Geol, BR-81531970 Curitiba, Parana, Brazil. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. Museu Hist Nat Capao Imbuia, BR-82810080 Curitiba, Parana, Brazil. RP Angulo, RJ (reprint author), Univ Fed Parana, Dept Geol, Cx P 19001, BR-81531970 Curitiba, Parana, Brazil. EM angulo@ufpr.br RI Souza, Maria/B-3005-2013; Angulo, Rodolfo/C-1516-2014 NR 18 TC 44 Z9 46 U1 0 U2 2 PU UNIV ARIZONA DEPT GEOSCIENCES PI TUCSON PA RADIOCARBON 4717 E FORT LOWELL RD, TUCSON, AZ 85712 USA SN 0033-8222 J9 RADIOCARBON JI Radiocarbon PY 2005 VL 47 IS 1 BP 67 EP 73 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 956ZI UT WOS:000231338500009 ER PT J AU Kennedy, MA Russell, AD Guilderson, TP AF Kennedy, MA Russell, AD Guilderson, TP TI A radiocarbon chronology of hunter-gatherer occupation from Bodega Bay, California, USA SO RADIOCARBON LA English DT Article ID AGE CALIBRATION; RESERVOIR AGES; CURRENT SYSTEM; C-14 DATA; COASTAL; PROGRAM; CHANNEL AB We present a Holocene radiocarbon chronology of hunter-gatherer occupation based on contemporaneous samples of charcoal and Mytilus californianus shell recovered from 7 archaeological sites near Bodega Bay, California, USA. A series of 127 C-14 ages reveals a chronological sequence that spans from 8940-110 cal BP (1 sigma). This sequence serves as a foundation for the interpretation of behavioral change along the northern California coast over the last 9000 yr, including the adaptive strategies used by human foragers to colonize and inhabit coastal areas of this region. These C-14 ages will also permit us to explore major dimensions of temporal change in Holocene ocean conditions (via marine reservoir corrections) and their potential effect on the resources available to ancient hunter-gatherers. C1 Univ Calif Davis, Dept Anthropol, Davis, CA 95616 USA. Univ Calif Davis, Dept Geog, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spect, Livermore, CA 94550 USA. RP Kennedy, MA (reprint author), Univ Calif Davis, Dept Anthropol, Davis, CA 95616 USA. EM makennedy@ucdavis.edu NR 36 TC 1 Z9 1 U1 1 U2 3 PU UNIV ARIZONA DEPT GEOSCIENCES PI TUCSON PA RADIOCARBON 4717 E FORT LOWELL RD, TUCSON, AZ 85712 USA SN 0033-8222 J9 RADIOCARBON JI Radiocarbon PY 2005 VL 47 IS 2 BP 265 EP 293 PG 29 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 954CY UT WOS:000231132900012 ER PT J AU Um, W Serne, RJ AF Um, W Serne, RJ TI Sorption and transport behavior of radionuclides in the proposed low-level radioactive waste disposal facility at the Hanford site, Washington SO RADIOCHIMICA ACTA LA English DT Article DE distribution coefficient; technetium; iodine; selenium; strontium ID MIGRATION; IODIDE; SEDIMENTS; MINERALS; ADSORPTION; ACTINIDES; INTERFACE; SURFACES; IODATE AB A series of batch sorption and column experiments was conducted to investigate sorption and transport behavior of Tc-99, I-129, Se-79, and Sr-90 on and through borehole sediments collected from the proposed low-level radioactive waste disposal facility at the Hanford Site (200 East Area). Batch sorption experiments were conducted on Hanford sediment using uncontaminated Hanford groundwater and simulated glass leachates spiked with individual radionuclides. Strongest sorption occurred for Sr-90, while Se-79 sorption was intermediate, and I-129 and Tc-99 showed the least sorption affinities on Hanford sediment among these radionuclides studied. The results of column experiments that measured transport behavior of these radionuclides through Hanford sediment were similar to the mobility that can be calculated from the batch sorption results, that is high mobility for Tc-99 and I-129 compared to the intermediate and strong retardation for Se-79 and Sr-90, respectively. These contaminant sorption data on sediments from below the proposed disposal facility, especially the tests using simulated glass leachate, corroborate values obtained for sediments collected in the past from near by locations and for generic solutions such as regional groundwater. These new data should provide more technical defensibility for past performance assessment predictions that did not use site-specific sediments and leachates. Further, the new data will be incorporated into future performance assessment activities that will update and improve past predictions. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Um, W (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM wooyong.um@pnl.gov NR 29 TC 22 Z9 22 U1 5 U2 20 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 1 BP 57 EP 63 DI 10.1524/ract.93.1.57.58295 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 898RM UT WOS:000227093900007 ER PT J AU Zavarin, M Roberts, SK Hakem, N Sawvel, AM Kersting, AB AF Zavarin, M Roberts, SK Hakem, N Sawvel, AM Kersting, AB TI Eu(III), Sm(III), Np(V), Pu(V), and Pu(IV) sokption to calcite SO RADIOCHIMICA ACTA LA English DT Article DE sorption; neptunium; plutonium; samarium; europium; calcite ID RARE-EARTH-ELEMENTS; COMMON MINERAL SURFACES; AQUEOUS-SOLUTIONS; SORPTION; SPECIATION; SEAWATER; MODEL; COMPLEXATION; SYSTEM; SPECTROSCOPY AB The sorption behavior of Eu(III), Sm(III), Np(V), Pu(V), and Pu(IV) in the presence of calcite and as a function of pH and carbonate alkalinity was measured by batch sorption experiments. Eu(III) and Sm(III) sorption is Similar, consistent with their observed aqueous speciation and precipitation behavior. For both rare earth elements, sorption decreases at the highest and lowest measured pHs. This is likely the result of speciation changes both of the calcite surface and the sorber. An increase in the equilibrium CO2(g) fugacity results in a shift in the sorption behavior to lower pH, consistent with a predicted aqueous speciation shift. Np(V) and Pu(V) sorption exhibited a strong pH dependence. For Np(V), K(d)s range from 0 to 217 mL/g suggesting that carbonate aqueous speciation as well as changes in the calcite surface speciation greatly affect Np(V) sorption to the calcite surface. Similar behavior was found for Pu(V). Pu(IV) sorption is also strongly pH dependent. Sorption decreases significantly at high pH as a result of Pu-carbonate complexation in solution. A surface complexation model of Sm(III), Eu(III), Np(V), Pu(V), and Pu(IV) sorption to the calcite surface was developed based on the calcite surface speciation model of Pokrovsky and Schott [1]. Sorption data were fit using one or two surface species for each sorber and could account for the effect of pH and CO2(g) fugacity on sorption. A relatively poor model fit to Pu(IV) sorption data at high pH may result from our poor understanding of Pu(IV)-carbonate aqueous speciation. While our surface complexation model may not represent a unique solution to the sorption data, it illustrates that a surface complexation modeling approach may adequately describe the sorption behavior of a number of radionuclides at the calcite surface over a range of solution conditions. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Zavarin, M (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave,L-221, Livermore, CA 94551 USA. EM zavarin1@llnl.gov NR 35 TC 47 Z9 47 U1 3 U2 48 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 2 BP 93 EP 102 DI 10.1524/ract.93.2.93.59413 PG 10 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 907MX UT WOS:000227723300004 ER PT J AU Hanson, B McNamara, B Buck, E Friese, J Jenson, E Krupka, K Arey, B AF Hanson, B McNamara, B Buck, E Friese, J Jenson, E Krupka, K Arey, B TI Corrosion of commercial spent nuclear fuel. 1. Formation of studtite and metastudtite SO RADIOCHIMICA ACTA LA English DT Article DE CSNF; hydrogen peroxide; studtite; metastudtite; air-water interface ID HYDROGEN PEROXIDE; URANIUM OXIDE; UO2; DISSOLUTION; OXIDATION; PRODUCTS; WATER AB The contact of commercial spent nuclear fuel (CSNF) with water over a 2-year period led to an unexpected corrosion phase and morphology. At short hydration times, crystallites of metaschoepite [(UO2)(8)O-2(OH)(12)](H2O)(10) were observed on the hydrated CSNF particles. Over the 2-year contact period, all evidence of metaschoepite disappeared, and the fuel particles were coated by a new alteration phase. Additionally, films of the reacted fuel were observed at the sample air-water interface of each sample. The corrosion phases on fuel powders and on the suspended films were examined by scanning electron microscopy, energy-dispersive X-ray fluorescence, and X-ray diffraction and were identified as studtite [(UO2)(O-2)(H2O)(2)](H2O)(2) and metastudtite (UO(4)center dot 2H(2)O), respectively. The reason for the partitioning of the latter phase to the sample air-water interface is unclear at this time but may be due to structural differences between the two phases. Scanning electron micrographs of the CSNF powders indicated surface corrosion along grain boundaries and fragmentation of the primary solid. The occurrence of studtite and metastudtite on CSNF could have implications for the potential attenuation of released radionuclides during oxidative corrosion of CSNF in a geologic repository. C1 Pacific NW Natl Lab, Radiochem Proc Lab, Richland, WA 99352 USA. RP McNamara, B (reprint author), Pacific NW Natl Lab, Radiochem Proc Lab, 902 Batelle Blvd, Richland, WA 99352 USA. EM bruce.mcnamara@pnl.gov RI Buck, Edgar/D-4288-2009; Buck, Edgar/N-7820-2013 OI Buck, Edgar/0000-0001-5101-9084 NR 51 TC 39 Z9 39 U1 3 U2 22 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 3 BP 159 EP 168 DI 10.1524/ract.93.3.159.61613 PG 10 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 916NL UT WOS:000228392300006 ER PT J AU McNamara, B Hanson, B Buck, E Soderquist, C AF McNamara, B Hanson, B Buck, E Soderquist, C TI Corrosion of commercial spent nuclear fuel. 2. Radiochemical analyses of metastudtite and leachates SO RADIOCHIMICA ACTA LA English DT Article DE CSNF; hydrogen peroxide; studtite; metastudtite; air-water interface; incorporation ID SOLUBILITY; WATER; UO2 AB Immersing commercial spent nuclear fuel (CSNF) in deionized water produced two corrosion products after a 2-year contact period. Suspensions of aggregates were observed to form at the air-water interface for each of five samples. These suspended aggregates were characterized by X-ray diffraction (XRD) to be metastudtite (UO(4)center dot 2H(2)O), while the corrosion present on the surface of the fuel itself was determined to be studtite [(UO2)(O-2)(H2O)(2)](H2O)(2)]. The presence of unreacted UO2 matrix was below the limits of detection by XRD for the three samples examined. The result prompted a radiochemical analysis of the solids collected from the sample air-water interface. The analysis indicated that high concentrations of Sr-90, Cs-137, and Tc-99, relative to the fuel inventory, had concentrated at the air-water interface along with the aggregates of metastudtite. Concentrations of Am-241 were at least two orders of magnitude lower than expected in these solids, and retention of Np-237 and Pu-219 into the corrosion product was observed. The combined radiochemical analyses of the air-water interface aggregates and leachate samples are a rare example of radionuclide partitioning to an alteration phase and may provide preliminary evidence for mechanisms that give rise to such noticeable departures from fuel-inventory values. The leachate radiochemical data are compared to existing data from hydration of the same CSNF. C1 Pacific NE Natl Lab, Radiochem Proc Lab, Richland, WA 99352 USA. RP McNamara, B (reprint author), Pacific NE Natl Lab, Radiochem Proc Lab, 902 Battelle Blvd, Richland, WA 99352 USA. EM bruce.mcnamara@pnl.gov RI Buck, Edgar/D-4288-2009; Buck, Edgar/N-7820-2013 OI Buck, Edgar/0000-0001-5101-9084 NR 25 TC 27 Z9 27 U1 0 U2 8 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 3 BP 169 EP 175 DI 10.1524/ract.93.3.169.61615 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 916NL UT WOS:000228392300007 ER PT J AU Wilson, RE Hu, YJ Nitsche, H AF Wilson, RE Hu, YJ Nitsche, H TI Detection and quantification of Pu(III, IV, V, and VI) using a 1.0-meter liquid core waveguide SO RADIOCHIMICA ACTA LA English DT Article DE plutonium; absorption spectroscopy; liquid core waveguide ID ABSORBENCY SPECTROSCOPY; PLUTONIUM IONS; WATER AB Detection and quantification of the aquo ions of Pu in 1 M HClO4 was carried out using a 1-meter liquid core waveguide (LCW) coupled to a fiber optic UV-Vis spectrometer. Detection limits of 7 x 10(-7) M for Pu(VI), 1.6 x 10(-5) M for Pu(V), 5 x 10(-6) M for Pu(IV) and 8 x 10(-6) M for Pu(III) were achieved. The limits of detection represent increases of 18 to 33 times those achievable using a conventional 1-cm path length. Because of the much lower detection limits of the LCW, routine identification of the oxidation states in dilute Pu solutions can be made. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Glen T Seaborg Ctr, Div Chem Sci, Berkeley, CA USA. Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA USA. RP Nitsche, H (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM HNitsche@lbl.gov RI Wilson, Richard/H-1763-2011 OI Wilson, Richard/0000-0001-8618-5680 NR 15 TC 17 Z9 17 U1 1 U2 5 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 4 BP 203 EP 206 DI 10.1524/ract.93.4.203.64075 PG 4 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 923RO UT WOS:000228927200003 ER PT J AU Zheng, ZP Wan, JM AF Zheng, ZP Wan, JM TI Release of contaminant U(VI) from soils SO RADIOCHIMICA ACTA LA English DT Article DE soil; uranium; release ID COMPLEX-FORMATION; URANIUM; CARBONATE; ADSORPTION; EXTRACTION; REDUCTION; GOETHITE; REMOVAL; PHASES; URANYL AB The retention, mobility, and bio-availability of U(VI) in contaminated soils depend strongly on release of U(VI). Laboratory batch experiments were performed to evaluate the factors (ionic strength of the extraction solution and solution volume to solid mass ratio) controlling the release of U(VI) from contaminated soil at Oak Ridge, Tennessee. Increase in ionic strength shows an evident effect on U(VI) release as indicated by the increase in release rates and associated release mass of U(VI). The ratio of solution volume to solid mass (V/M) has a significant impact on the release of U(VI). Increase in the V/M ratio shows a negligible effect on the U(VI) release over a 4-day period. However, at Day 30 and Day 120, larger V/M ratios cause greater U(VI) release. The maximum U(VI) concentrations observed in the release experiments are in the range of schoepite solubility estimated under conditions relevant to the experiments, suggesting that schoepite solubility primarily controls the U(VI) release, but that solubilization and desorption effects cannot be distinguished using macroscopic methods. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Zheng, ZP (reprint author), Lawrence Berkeley Lab, MS 70-108B, Berkeley, CA 94720 USA. EM zzuoping@lbl.gov RI Wan, Jiamin/H-6656-2014 NR 33 TC 7 Z9 7 U1 0 U2 3 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 4 BP 211 EP 217 DI 10.1524/ract.93.4.211.64071 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 923RO UT WOS:000228927200005 ER PT J AU Douglas, M Clark, SB Friese, JI Arey, BW Buck, EC Hanson, BD Utsunomiya, S Ewing, RC AF Douglas, M Clark, SB Friese, JI Arey, BW Buck, EC Hanson, BD Utsunomiya, S Ewing, RC TI Microscale characterization of uranium(VI) silicate solids and associated neptunium(V) SO RADIOCHIMICA ACTA LA English DT Article DE uranyl; solid solution; spent nuclear fuel; uranium minerals; uranophane ID SPENT NUCLEAR-FUEL; SODIUM BOLTWOODITE; OXIDIZING CONDITIONS; OXIDATIVE CORROSION; URANYL COMPOUNDS; WASTE-DISPOSAL; YUCCA MOUNTAIN; UO2; 90-DEGREES-C; PRECIPITATION AB The uranium(VI) silicate phases uranophane, Ca[(UO2)(SiO3OH)](2)(.)5H(2)O, and sodium boltwoodite, Na[(UO2)(SiO3OH)](.)1.5H(2)O, were synthesized in the presence of small, variable quantities (0.5-2.0 mol% relative to U) of pentavalent neptunium (Np(V), as NpO2+), to investigate the nature of its association with these U(VI) solid phases. Solids were characterized by X-ray powder diffraction (XRD), gamma spectrometry (GS), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM) with electron energy-loss spectroscopy (EELS). Neptunium concentration was determined in the bulk solid phases by GS and was found to range from 780-15800 mu g/g. In some cases, Np distributions between the aqueous and solid phases were monitored, and 78%-97% of the initial Np was associated with the isolated solid. Characterization of individual crystallites by TEM/EELS suggests the Np is associated with the U(VI) phase. No discrete Np phases, such as Np oxides, were observed. Because the U(VI) silicates are believed to be important solubility-controlling solids on a geologic timescale, these results suggest that the partitioning of the minor actinides to these solids must be considered when assessing the performance of a waste repository for spent nuclear fuel. C1 Washington State Univ, Dept Chem, Pullman, WA 99163 USA. Washington State Univ, Ctr Multiphase Environm Res, Pullman, WA 99163 USA. Pacific NW Natl Lab, Radiochem Sci & Engn Grp, Richland, WA 99352 USA. Univ Michigan, Nucl Engn & Radiol Sci Dept, Ann Arbor, MI 48109 USA. RP Clark, SB (reprint author), Washington State Univ, Dept Chem, Pullman, WA 99163 USA. EM s_clark@wsu.edu RI Buck, Edgar/D-4288-2009; Buck, Edgar/N-7820-2013; OI Buck, Edgar/0000-0001-5101-9084; Douglas, Matthew/0000-0001-9708-1780 NR 35 TC 23 Z9 23 U1 0 U2 13 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 5 BP 265 EP 272 DI 10.1524/ract.93.5.265.64281 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 935LP UT WOS:000229784100003 ER PT J AU Wellman, DM Catalano, JG Icenhower, JP Gamerdinger, AP AF Wellman, DM Catalano, JG Icenhower, JP Gamerdinger, AP TI Synthesis and characterization of sodium meta-autunite, Na[UO2PO4]center dot 3H(2)O SO RADIOCHIMICA ACTA LA English DT Article DE sodium-autunite; uranyl-phosphates; uranium; phosphates; mineralogy; synthesis ID URANYL PHOSPHATES AB Long-chain sodium polyphosphate compounds have been recently proposed as a "time-released" source of phosphate for precipitation of uranium-phosphate minerals. Elevated sodium concentrations presented by this technique promote the formation of sodium autunite relative to the more common calcium autunite mineral phase. In order to evaluate sodium autunite minerals as a long-term "sink" for in-situ immobilization of uranium, it is necessary to quantify their longevity under environmentally relevant conditions. This paper describes a direct method for precipitating sodium autunite and provides a comparative analysis of the structural and chemical properties of direct versus indirectly precipitated sodium autunite. Extended X-ray absorption fine structure (EXAFS) spectroscopy, chemical digestion followed by inductively-coupled plasma-optical emission spectroscopy (ICP-OES) and inductivety-coupled plasma-mass spectroscopy (ICP-MS) for elemental analyses, X-ray diffraction (XRD), scanning electron microscopy (SEM), multi point Brunauer-Emmett-Teller (BET) analyses and helium pyconometry were used to characterize the precipitate phases. Morphological differences are discussed in the context of conducting subsequent solubility and dissolution investigations. Research presented here is part of a larger effort to quantify the solubility and dissolution properties of uranium-phosphate minerals. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Washington State Univ, Dept Chem, Pullman, WA 99164 USA. Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. Univ Arizona, Dept Soil Water & Environm Sci, Tucson, AZ 85721 USA. RP Wellman, DM (reprint author), Pacific NW Natl Lab, POB 999,K6-81, Richland, WA 99352 USA. EM dawn.wellman@pnl.gov RI Icenhower, Jonathan/E-8523-2011; Catalano, Jeffrey/A-8322-2013 OI Catalano, Jeffrey/0000-0001-9311-977X NR 21 TC 14 Z9 15 U1 2 U2 18 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 7 BP 393 EP 399 DI 10.1524/ract.2005.93.7.393 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 952PI UT WOS:000231017600005 ER PT J AU Felmy, AR Xia, YX Wang, ZM AF Felmy, AR Xia, YX Wang, ZM TI The solubility product of NaUO2PO4 center dot xH(2)O determined in phosphate and carbonate solutions SO RADIOCHIMICA ACTA LA English DT Article DE sodium uranium phosphate; solubility product; pitzer ion-interaction parameters; uranium carbonate complexes; solution ID NATURAL-WATERS; PREDICTION; SYSTEM AB The solubility product of NaUO(2)PO(4)center dot xH(2)O was determined in phosphate containing solutions at low pC(H+) values in the absence of carbonate and at higher pC(H+) values in the presence of carbonate. NaUO(2)PO(4 center dot)xH(2)O exhibited very low solubilities (similar to 10(-7) M in U) over a broad range of hydrogen ion concentrations, NaNO3 concentrations and in the absence of added carbonate. Time Resolved Laser Fluorescence Spectroscopy (TRLFS) analysis of non-carbonate solutions outside of the acidic region revealed the presence of complex mixtures of aqueous U(VI) hydroxyl or phosphate species and uranium phosphate nanoparticles. The presence of the nanoparticles made it impossible to accurately calculate a solubility product for NaUO2PO4-xH(2)O in the absence of carbonate and at higher pC(H+) values. Therefore in order to increase the concentration of U(VI) in solution and thereby verify the solubility product calculated from the most acidic samples, we systematically introduced know concentrations of carbonate, which resulted in the formation of U(VI) carbonate complexes. Development of an accurate aqueous thermodynamic model for the aqueous U(VI) carbonate complexes then allowed calculation of a solubility product for NaUO(2)PO(4)center dot xH(2)O in the higher pH samples which was in good agreement with the values for the more acidic samples. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Felmy, AR (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM ar.felmy@pnl.gov RI Wang, Zheming/E-8244-2010 OI Wang, Zheming/0000-0002-1986-4357 NR 16 TC 15 Z9 15 U1 1 U2 6 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 7 BP 401 EP 408 DI 10.1524/ract.2005.93.7.401 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 952PI UT WOS:000231017600006 ER PT J AU Rai, DP Yui, M Hess, NJ Felmy, AR Moore, DA AF Rai, DP Yui, M Hess, NJ Felmy, AR Moore, DA TI Thorium reactions in borosilicate-glass/water systems SO RADIOCHIMICA ACTA LA English DT Article DE thermodynamics; thorium oxide; thorium silicate; solubility; borosilicate glass dissolution; carbonato complexes of thorium ID MULTIPLE-SCATTERING CALCULATIONS; ABSORPTION FINE-STRUCTURE; HYDROUS OXIDE; SOLUBILITY PRODUCT; NATURAL-WATERS; GLASS; TH(IV); EQUILIBRIA; PREDICTION; SPECIATION AB Studies were conducted on the dissolution of Th-doped borosilicate glass, a complex assemblage of 24 different elements in various proportions, in a wide range of pH values (0.5 to 12) and carbonate (as high as 6.2 m) and bicarbonate (as high as 1.0 m) concentrations, and as a function of time to determine whether the observed thorium concentrations exhibit an equilibrium phenomenon and to ascertain whether existing thermodynamic data can be used to interpret these results. Measurable Th concentrations were observed in either the very acidic (pH 0.5 to 4) solutions or alkaline solutions containing relatively high carbon ate/bicarbonate concentrations. Steady state Th concentrations were reached over time from both the oversaturation and undersaturation directions, indicating that Th concentrations are controlled by an equilibrium solubility phenomenon. The XRD, EXAFS, and thermodynamic analyses of solubility data failed to definitively identify the nature of the solubility-controlling solid in this complex system; however, the data suggests that the solubility-controlling solid most likely involves the Th-silicate phase and that the observed Th concentrations are up to many orders of magnitude lower than in equilibrium with ThO2(am). The solubility study also showed that existing thermodynamic data for carbonato complexes of Th can be used to reliably predict Th concentrations in relatively dilute to concentrated carbonate/ bicarbonate solutions. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Japan Nucl Cycle Dev Inst, Tokai Works, Tokai, Ibaraki, Japan. RP Rai, DP (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM dhan.rai@pnl.gov OI Hess, Nancy/0000-0002-8930-9500 NR 34 TC 2 Z9 2 U1 0 U2 4 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 8 BP 443 EP 455 DI 10.1524/ract.2005.93.8.443 PG 13 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 961YW UT WOS:000231698900002 ER PT J AU Adu-Wusu, K Hassan, NM Nash, CA Marra, JC AF Adu-Wusu, K Hassan, NM Nash, CA Marra, JC TI Removal of cesium from alkaline waste solution: Part I - Batch ion exchange study SO RADIOCHIMICA ACTA LA English DT Article DE SuperLig; resin; cesium; batch sorption; isotherm; distribution coefficient ID SILICA-GEL; SUPERLIG(R)644 RESIN; SORPTION; TEMPERATURE; SEPARATION; ADSORPTION; PHOSPHATE AB Batch ion exchange tests have been employed to evaluate the ability of SuperLig (R) 644 resin to remove Cs-137 from highly alkaline nuclear waste solution. The batch sorption data indicated the SuperLig' 644 resin has a relatively high sorption affinity for cesium with a predicted number of bed volumes required to reach 50% breakthrough in a column operation (generally known as lambda value) of similar to 400 based on an initial total cesium concentration of 12.1 mu g/mL. The sorption data also obey the Freundlich and Dubinin-Radushkevich isotherms. C1 Savannah River Natl Lab, Aiken, SC 29808 USA. RP Adu-Wusu, K (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. EM kofi.adu-wusu@srs.gov NR 29 TC 2 Z9 2 U1 0 U2 4 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 8 BP 457 EP 463 DI 10.1524/ract.2005.93.8.457 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 961YW UT WOS:000231698900003 ER PT J AU Adu-Wusu, K Hassan, NM Nash, CA Marra, JC AF Adu-Wusu, K Hassan, NM Nash, CA Marra, JC TI Removal of cesium from alkaline waste solution: Part II - Column ion exchange study SO RADIOCHIMICA ACTA LA English DT Article DE SuperLig; resin; cesium; column sorption; breakthrough curve; elution ID SILICA-GEL; SEPARATION AB Column ion exchange tests have been used to demonstrate the ability of SuperLig (R) 644 resin to remove Cs-137 from highly alkaline radioactive waste. The column test resulted in Cs-137 removal and overall decontamination factor of 99.6% (lead column) and 517000 (lag column) respectively. The concentration Of (CS)-C-137 in the lag column effluent (0.000423 mu Ci (CS)-C-137 /mL) was two orders of magnitude below the low-activity waste vitrification limit of 0.087 mu Ci Cs-137/mL. The bed volume (BV = 175) at the onset of breakthrough exceeded the requirement of 100BV at 50% breakthrough. Cesium elution with 0.5 M HNO3 was adequate with a peak BV of 3.5. C/C-0 = 0.01 occurred at 10 BV of eluant, which is less than the target of 15BV. Further, 99.99% of sorbed cesium was eluted from the resin. The residual (CS)-C-137 on the regenerated resin after the column operation was 23 mu Ci/g dry Na+ form resin. C1 Savannah River Natl Lab, Aiken, SC 29808 USA. RP Adu-Wusu, K (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. EM kofi.adu-wusu@srs.gov NR 20 TC 4 Z9 4 U1 1 U2 3 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 8 BP 465 EP 470 DI 10.1524/ract.2005.93.8.465 PG 6 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 961YW UT WOS:000231698900004 ER PT J AU Neu, MP Icopini, GA Boukhalfa, H AF Neu, MP Icopini, GA Boukhalfa, H TI Plutonium speciation affected by environmental bacteria SO RADIOCHIMICA ACTA LA English DT Article DE plutonium; actinide; speciation; biogeochemistry; bioaccumulation; bioremediation; metal-reducing bacteria; siderophore; biofilm ID CITROBACTER SP; HUMIC ACIDS; CADMIUM ACCUMULATION; BIOLOGICAL REDUCTION; STABILITY-CONSTANTS; MICROBIAL REDUCTION; SEQUESTERING AGENTS; URANIUM REDUCTION; REDUCING BACTERIA; METAL-IONS AB Plutonium has no known biological utility, yet it has the potential to interact with bacterial cellular and extracellular structures that contain metal-binding groups, to interfere with the uptake and utilization of essential elements, and to alter cell metabolism. These interactions can transform plutonium from its most common forms, solid, mineral-adsorbed, or colloidal Pu(IV), to a variety of biogeochemical species that have much different physico-chemical properties. Organic acids that are extruded products of cell metabolism can solubilize plutonium and then enhance its environmental mobility, or in some cases facilitate plutonium transfer into cells. Phosphate- and carboxylate-rich polymers associated with cell walls can bind plutonium to form mobile biocolloids or Pu-laden biofilm/mineral solids. Bacterial membranes, proteins or redox agents can produce strongly reducing electrochemical zones and generate molecular Pu(III/IV) species or oxide particles. Alternatively, they can oxidize plutonium to form soluble Pu(V) or Pu(VI) complexes. This paper reviews research on plutonium-bacteria interactions and closely related studies on the biotransformation of uranium and other metals. C1 Los Alamos Natl Lab, Div Chem, C SIC, Los Alamos, NM 87545 USA. RP Neu, MP (reprint author), Los Alamos Natl Lab, Div Chem, C SIC, POB 1663, Los Alamos, NM 87545 USA. EM mneu@lanl.gov NR 107 TC 35 Z9 35 U1 0 U2 21 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 11 BP 705 EP 714 DI 10.1524/ract.2005.93.11.705 PG 10 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 989IN UT WOS:000233666200009 ER PT J AU Hummel, W Anderegg, G Puigdomenech, I Rao, LF Tochiyama, O AF Hummel, W Anderegg, G Puigdomenech, I Rao, LF Tochiyama, O TI The OECD/NEA TDB review of selected organic ligands SO RADIOCHIMICA ACTA LA English DT Article DE thermodynamics; database; equilibrium constants; organic ligands; specific ion interaction theory ID SOLUBILITY; MONOHYDRATE AB Within the scope of the OECD Nuclear Energy Agency (NEA) Thermochemical Data Base Project (TDB) a comprehensive review of selected organic ligands has been carried out by the authors. The selected ligands are oxalate, citrate, ethyl enediaminetetraacetate (edta) and alpha-isosaccharinate (isa), and the elements considered in the review are U, Np, Pu, Am, Tc, Ni, Se and Zr, as well as the necessary basic data concerning protonation of the ligands and interactions with the major competing elements Na, K, Mg and Ca. This review on organic ligands showed that the pragmatic ionic strength correction procedure, the Specific ion Interaction Theory (SIT), chosen as the default method for all NEA TDB reviews, can be applied successfully also to organic ligands. The SIT interaction parameters derived from ligand protonation data for different media, e.g. NaCl and KCl, pass the consistency test when applied to other systems evaluated in the organics review, e.g. solubility data. Hence, the thermodynamic constants selected in this NEA TDB organics review can be used with some confidence in real world applications, provided that SIT is used in the speciation calculations. C1 Paul Scherrer Inst, Lab Waste Management, CH-5232 Villigen, Switzerland. ETH, Swiss Fed Inst Technol, CH-8092 Zurich, Switzerland. Swedish Nucl Fuel & Waste Management Co, SKB, S-10240 Stockholm, Sweden. Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. Tohoku Univ, Inst Multidisciplinary Res Adv Mat, Sendai, Miyagi 9808577, Japan. RP Hummel, W (reprint author), Paul Scherrer Inst, Lab Waste Management, CH-5232 Villigen, Switzerland. EM wolfgang.hummel@psi.ch NR 19 TC 7 Z9 7 U1 2 U2 9 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 11 BP 719 EP 725 DI 10.1524/ract.2005.93.11.719 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 989IN UT WOS:000233666200011 ER PT J AU Wang, Z Felmy, AR Xia, YX Qafoku, O Yantassee, W Cho, H AF Wang, Z Felmy, AR Xia, YX Qafoku, O Yantassee, W Cho, H TI Complexation of Cm(III)/Eu(III) with silicates in basic solutions SO RADIOCHIMICA ACTA LA English DT Article DE Cm3+; fluorescence; laser-induced time-resolved spectroscopy; nanoparticle; silicate; Eu3+ ID LASER FLUORESCENCE SPECTROSCOPY; ALKALI-METAL CATIONS; SILICIC-ACID; AQUEOUS-SOLUTIONS; NMR-SPECTROSCOPY; 25-DEGREES-C; CM(III); ALUMINUM(III); EUROPIUM(III); LUMINESCENCE AB The complexation of Cm(III) and Eu(III) with dissolved silica was studied by solubility measurement and time resolved laser fluorescence spectroscopy (TRLFS) in basic solutions over a range of total silica concentrations and ionic strengths (NaNO3)- In initial experiments on the solubility of Eu(OH)3 in silicate containing solutions we observed a rapid increase in the soluble Eu(III) concentration under basic conditions. The Eu(III)/Cm(III) silicate complexes that formed caused a significant increase of the hypersensitive D-5(0) -> F-7(2) band around 615 nm relative to the non-hypersensitive D-5(0) -> F-7(1) band at 592 nm for Eu(III). Further studies of Eu(III) and Cm(III) containing solutions showed a shift of the fluorescence spectral maximum from 594 nm to up to 607 nm for Cm(III) along with a significant increase of fluorescence intensities. The fluorescence lifetimes for Eu(III) species increased from 115 mu s to 1.8 ms in 3.0 M and 5.0 M NaNO3, corresponding to full coordination I and from 68 mu s to 202 mu s for Cm(III) in 0. 1 M NaNO3, consistent with the removal of 6-7 water molecules upon silicate complexation. The variations of the fluorescence intensity and the concentrations of the monomeric and polymeric silicates suggested that in basic silicate solutions, Eu(III)/Cm(III) mainly complexes with polysilicates. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wang, Z (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM zheming.wang@pnl.gov RI Wang, Zheming/E-8244-2010 OI Wang, Zheming/0000-0002-1986-4357 NR 26 TC 12 Z9 12 U1 2 U2 12 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2005 VL 93 IS 12 BP 741 EP 748 DI 10.1524/ract.2005.93.12.741 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 000RK UT WOS:000234479900003 ER PT J AU Asano, KG Ford, MJ Tomkins, BA Van Berkel, GJ AF Asano, KG Ford, MJ Tomkins, BA Van Berkel, GJ TI Self-aspirating atmospheric pressure chemical ionization source for direct sampling of analytes on surfaces and in liquid solutions SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID DESORPTION ELECTROSPRAY-IONIZATION; THIN-LAYER-CHROMATOGRAPHY; TANDEM MASS-SPECTROMETRY; AMBIENT CONDITIONS; HUMAN PLASMA; SEPARATIONS; DEVICE; PROBE AB A self-aspirating heated nebulizer probe is described and demonstrated for use in the direct analysis of analytes on surfaces and in liquid samples by atmospheric pressure chemical ionization (APCI) mass spectrometry. Functionality and performance of the probe as a self-aspirating APCI source is demonstrated using reserpine and progesterone as test compounds. The utility of the probe to sample analytes directly from surfaces was demonstrated first by scanning development lanes of a reversed-phase thin-layer chromatography plate in which a three-component dye mixture, viz., Fat Red 7B, Solvent Green 3, and Solvent Blue 35, was spotted and the components were separated. Development lanes were scanned by the sampling probe operated under computer control (x, y plane) while full-scan mass spectra were recorded using a quadrupole ion trap mass spectrometer. In addition, the ability to sample the surface of pharmaceutical tablets (viz., Extra Strength Tylenol(R) and Evista(R) tablets) and to detect the active ingredients (acetaminophen and raloxifene, respectively) selectively was demonstrated using tandem mass spectrometry (MS/MS). Finally, the capability to sample analyte solutions from the wells of a 384-well microtiter plate and to perform quantitative analyses using MS/MS detection was illustrated with cotinine standards spiked with cotinine-d(3) as an internal standard. Published in 2005 by John Wiley & Sons, Ltd. C1 Oak Ridge Natl Lab, Div Chem Sci, Organ & Biol Mass Spectrometry Grp, Oak Ridge, TN 37831 USA. RP Van Berkel, GJ (reprint author), Oak Ridge Natl Lab, Div Chem Sci, Organ & Biol Mass Spectrometry Grp, Oak Ridge, TN 37831 USA. EM vanberkelgj@ornl.gov RI Asano, Keiji/L-3164-2016; OI Asano, Keiji/0000-0003-2254-3586; Tomkins, Bruce/0000-0001-8520-1415 NR 18 TC 36 Z9 39 U1 4 U2 12 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 2005 VL 19 IS 16 BP 2305 EP 2312 DI 10.1002/rcm.2062 PG 8 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 954NS UT WOS:000231162400013 PM 16021617 ER PT J AU Dickson, S AF Dickson, S TI Creating tactile captions in three-dimensional computer-aided design and manufacturing SO RAPID PROTOTYPING JOURNAL LA English DT Article DE visual perception; feedback; computer aided design; computer aided manufacturing; Braille AB Purpose - This paper aims to present new work on a topic/which has received very little attention. Design/methodology/approach - Rapid prototyping technology is used to provide access to 3D computer graphics and visualization for people with visual disabilities. Software and techniques for composing DotsPlus(tm) Braille text in a three-dimensional computer-aided design (CAD) and rapid prototyping system are presented. Findings - Vision-limited people and people with cognitive or learning disabilities can benefit from casting the results of scientific computing into physical form using rapid prototyping. Research limitations/implications - Not much is known about the extent of three-dimensional spatial cognition in people with the kinds of disabilities who might benefit from this work. The argument for this application of rapid prototyping remains to be tested in a laboratory or classroom environment. The manufacturing principles in a limited test scenario are presented here. Work remains to be done to develop software in order to manufacture polygon mesh models from an arbitrary scientific visualization via rapid prototyping with tactile captions applied. Practical implications - The CAD modeling and rapid prototyping innovations suggested in this paper will create pedagogical models, which are sufficiently robust to withstand the classroom and will lower the cost of producing and distributing these models. Originality/value - Rapid prototyping has only been used on three documented occasions in the past to create experimental models of scientific information for the blind. There has been no attempt prior to now to integrate captions with these tactile models. These models have not been in general use for education of persons with visual, cognitive or learning disabilities. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Dickson, S (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. NR 14 TC 1 Z9 1 U1 0 U2 3 PU EMERALD GROUP PUBLISHING LIMITED PI BRADFORD PA 60/62 TOLLER LANE, BRADFORD BD8 9BY, W YORKSHIRE, ENGLAND SN 1355-2546 J9 RAPID PROTOTYPING J JI Rapid Prototyping J. PY 2005 VL 11 IS 5 BP 293 EP 297 DI 10.1108/13552540510623602 PG 5 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 986MQ UT WOS:000233454100005 ER PT S AU Vaniman, D Bish, D Chipera, S AF Vaniman, D Bish, D Chipera, S BE Johannesson, KH TI Lanthanide elements in alteration minerals as a guide to transport phenomena in the vadose zones of continental tuffs SO RARE EARTH ELEMENTS IN GROUNDWATER FLOW SYSTEMS SE Water Science and Technology Library LA English DT Proceedings Paper CT Annual Meeting of the Geological-Society-of-America CY NOV, 2000 CL RENO, NV SP Geol Soc Amer ID RARE-EARTH ELEMENTS; YUCCA MOUNTAIN; MANGANESE OXIDE; BANDELIER-TUFF; NEW-MEXICO; CALCITE; NEVADA; WATER; USA; GROUNDWATER C1 Los Alamos Natl Lab, Grp EES6, Los Alamos, NM 87545 USA. RP Vaniman, D (reprint author), Los Alamos Natl Lab, Grp EES6, MS D462, Los Alamos, NM 87545 USA. NR 30 TC 1 Z9 1 U1 1 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0921-092X BN 1-4020-3233-1 J9 WATER SCI TECHNOL LI PY 2005 VL 51 BP 111 EP 140 PG 30 WC Geochemistry & Geophysics; Water Resources SC Geochemistry & Geophysics; Water Resources GA BDY52 UT WOS:000236177200005 ER PT S AU Rader, DJ Gallis, MA Torczynski, JR Wagner, W AF Rader, DJ Gallis, MA Torczynski, JR Wagner, W BE Capitelli, M TI DSMC convergence behavior for Fourier flow SO RAREFIED GAS DYNAMICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 24th International Symposium on Rarefied Gas Dynamics (RGD24) CY JUL 10-16, 2004 CL Monopoli, ITALY SP Inst Metodol Inorgan Plasmi, Univ Bari & Dept Chem, USAF UK, European Off Aerosp Res & Dev, European Space Agcy, ESTEC, Grp Nazl Fis Matemat, ALTA-CENTROSPAZIO, Assessorato Turismo-Reg Puglia, Comune Alberobello, COMPULAB-Rivenditore Autozzato Apple, Fond Cassa Risparm Pugl ID SIMULATION MONTE-CARLO; BOLTZMANN-EQUATION; MOLECULAR-DYNAMICS; STATISTICAL ERROR; GAS AB The convergence behavior of Bird's Direct Simulation Monte Carlo (DSMC) method is explored for near-continuum, one-dimensional Fourier flow. An argon-like, hard-sphere gas is confined between two parallel, fully accommodating, motionless walls of unequal temperature. The simulations are performed using a one-dimensional code based on Bird's DSMC prescription. The convergence metric is taken as the ratio of the DSMC-calculated bulk thermal conductivity to the infinite-approximation, Chapman-Enskog (CE) theoretical value. The convergence rate is monitored with respect to three parameters: time step, cell size, and number of computational molecules per cell. For a sufficiently large number of computational molecules, the DSMC discretization error is observed to decrease quadratically with time step and cell size, in good agreement with previous predictions based on Green-Kubo theory. When all three parameters are finite, the observed convergence behavior is complex. As numerical errors are systematically reduced, the DSMC-calculated conductivity is shown to approach the theoretical CE value to within 0.02%, showing that the present implementation of Bird's DSMC algorithm provides an excellent representation of continuum, CE heat conduction. C1 Sandia Natl Labs, Engn Sci Ctr, POB 5800, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Engn Sci Ctr, POB 5800, Albuquerque, NM 87185 USA. NR 22 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0247-7 J9 AIP CONF PROC PY 2005 VL 762 BP 473 EP + PG 2 WC Physics, Fluids & Plasmas SC Physics GA BCQ51 UT WOS:000230775600075 ER PT S AU Torczynski, JR Gallis, MA Rader, DJ AF Torczynski, JR Gallis, MA Rader, DJ BE Capitelli, M TI DSMC Simulations of Fourier and Couette flow: Chapman-Enskog behavior and departures therefrom SO RAREFIED GAS DYNAMICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 24th International Symposium on Rarefied Gas Dynamics (RGD24) CY JUL 10-16, 2004 CL Monopoli, ITALY SP Inst Metodol Inorgan Plasmi, Univ Bari & Dept Chem, USAF UK, European Off Aerosp Res & Dev, European Space Agcy, ESTEC, Grp Nazl Fis Matemat, ALTA-CENTROSPAZIO, Assessorato Turismo-Reg Puglia, Comune Alberobello, COMPULAB-Rivenditore Autozzato Apple, Fond Cassa Risparm Pugl ID MONTE-CARLO-SIMULATION; BOLTZMANN-EQUATION AB Bird's Direct Simulation Monte Carlo (DSMC) method is used to compute the molecular velocity distribution of a nonequilibrium monatomic gas to compare with Chapman-Enskog (CE) theory. The gas is confined between two parallel, fully accommodating walls, which either are motionless and have unequal temperatures (Fourier flow) or are moving tangentially and oppositely and have equal temperatures (Couette flow). Molecules with inverse-power-law potentials from hard-sphere through Maxwell are examined. For Fourier and Couette flow with small heat-flux or shear-stress Knudsen numbers, DSMC reproduces the CE thermal conductivity, viscosity, and Sonine-polynomial coefficients outside the Knudsen layers. For Fourier flow with larger heat-flux Knudsen numbers, the thermal conductivity continues to agree with the CE value, but systematic differences in the Sonine-polynomial coefficients are observed and are quantified in terms of the heat-flux Knudsen number for hard-sphere and Maxwell interactions. Thus, DSMC can determine the state of a gas when CE theory does not apply and can be used to assess other analytical or numerical methods purporting to solve the Boltzmann equation. C1 Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. NR 10 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0247-7 J9 AIP CONF PROC PY 2005 VL 762 BP 620 EP + PG 2 WC Physics, Fluids & Plasmas SC Physics GA BCQ51 UT WOS:000230775600099 ER PT S AU Gallis, MA Boyles, KA LeBeau, GJ AF Gallis, MA Boyles, KA LeBeau, GJ BE Capitelli, M TI DSMC simulations in support of the STS-107 accident investigation SO Rarefied Gas Dynamics SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 24th International Symposium on Rarefied Gas Dynamics (RGD24) CY JUL 10-16, 2004 CL Monopoli, ITALY SP Inst Metodol Inorgan Plasmi, Univ Bari & Dept Chem, USAF UK, European Off Aerosp Res & Dev, European Space Agcy, ESTEC, Grp Nazl Fis Matemat, ALTA-CENTROSPAZIO, Assessorato Turismo-Reg Puglia, Comune Alberobello, COMPULAB-Rivenditore Autozzato Apple, Fond Cassa Risparm Pugl AB Three-dimensional Direct Simulation Monte Carlo simulations of Columbia Shuttle Orbiter flight STS-107 are presented. The aim of this work is to determine the aerodynamic and heating behavior of the Orbiter during aerobraking maneuvers and to provide piecewise integration of key scenario events to assess the plausibility of the candidate failure scenarios. The flight of the Orbiter is examined at two altitudes: 350 kft and 300 kft. The flow field around the Orbiter and the heat transfer to it are calculated for the undamaged configuration. The flow inside the wing for an assumed damage to the leading edge in the form of a 10-inch hole is studied. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Gallis, MA (reprint author), POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0247-7 J9 AIP CONF PROC PY 2005 VL 762 BP 1211 EP 1216 PG 6 WC Physics, Fluids & Plasmas SC Physics GA BCQ51 UT WOS:000230775600192 ER PT S AU Navratil, P Ormand, WE Caurier, E Bertulani, C AF Navratil, P Ormand, WE Caurier, E Bertulani, C BE Brown, BA TI No-core shell model and reactions SO REACTION MECHANISMS FOR RARE ISOTOPE BEAMS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 2nd Argonne/MSU/JINA/INT RIA Workshop CY MAR 09-12, 2005 CL E Lansing, MI SP Natl Superconducting Cyclotron Lab, Argonne Natl Lab, Joint inst Nucl Astrophys, Inst Nucl Theory DE shell model; forces in hadronic systems and effective interactions; direct reactions; spectroscopic factors; radiative capture ID MONTE-CARLO CALCULATIONS; LIGHT-NUCLEI; OPTICAL-MODEL; 1P SHELL; COULOMB; B-8; MEV/NUCLEON; SCATTERING; ENERGIES AB There has been a significant progress in ab initio approaches to the structure of light nuclei. Starting from realistic two- and three-nucleon interactions the ab initio no-core shell model (NCSM) can predict low-lying levels in p-shell nuclei. It is a challenging task to extend ab initio methods to describe nuclear reactions. In this contribution, we present a brief overview of the NCSM with examples of recent applications as well as the first steps taken toward nuclear reaction applications. In particular, we discuss cross section calculations of p+Li-6 and He-6+p scattering as well as a calculation of the astrophysically important Be-7(p,gamma)B-8 S-factor. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Navratil, P (reprint author), Lawrence Livermore Natl Lab, POB 808,L-414, Livermore, CA 94551 USA. NR 40 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0280-9 J9 AIP CONF PROC PY 2005 VL 791 BP 32 EP 39 PG 8 WC Physics, Nuclear SC Physics GA BDM64 UT WOS:000234314200004 ER PT S AU Escher, J Dietrich, FS AF Escher, J Dietrich, FS BE Brown, BA TI Determining cross sections for reactions on unstable nuclei: A consideration of indirect approaches SO Reaction Mechanisms for Rare Isotope Beams SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 2nd Argonne/MSU/JINA/INT RIA Workshop CY MAR 09-12, 2005 CL E Lansing, MI SP Natl Superconducting Cyclotron Lab, Argonne Natl Lab, Joint inst Nucl Astrophys, Inst Nucl Theory DE statistical compound-nucleus reactions; indirect methods; unstable nuclei ID ACTINIDE NUCLEI; S-FACTOR; FISSION; NORMALIZATION; STATES AB An indirect method for determining cross sections for reactions proceeding through a compound nucleus is presented. The appropriate theoretical framework for applications of this method is reviewed and theoretical and experimental challenges that need to be addressed in applications of the method are outlined. Two approximations are considered and their advantages and limitations are discussed. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Escher, J (reprint author), Lawrence Livermore Natl Lab, POB 808,L-414, Livermore, CA 94550 USA. RI Escher, Jutta/E-1965-2013 NR 25 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0280-9 J9 AIP CONF PROC PY 2005 VL 791 BP 93 EP 100 PG 8 WC Physics, Nuclear SC Physics GA BDM64 UT WOS:000234314200011 ER PT S AU Li, ST AF Li, ST BE Shi, ZC Chen, Z Tang, T Yu, D TI Adaptive mesh refinement and its application to magneto-hydrodynamics SO Recent Advances in Adaptive Computation, Proceedings SE CONTEMPORARY MATHEMATICS SERIES LA English DT Proceedings Paper CT International Conference on Recent Advances in Adaptive Computation CY MAY 24-28, 2004 CL Zhejiang Univ, Hangzhou, PEOPLES R CHINA SP Chinese Acad Sci, Inst Computat Math, Chinese Acad Sci, Int Res Team Complex Syst, Minist Sci & Technol china, Large Scale Computat Res Project HO Zhejiang Univ ID ALGORITHM; EQUATIONS AB In this paper we present three improvements over the Berger-Colella's adaptive mesh refinement (AMR) approach: adaptive clustering algorithm, conservative prolongation and restriction for cylindrical and spherical grid, and divergence-free reconstruction for AMR. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Li, ST (reprint author), Los Alamos Natl Lab, Div Theoret, MS B284, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER MATHEMATICAL SOC PI PROVIDENCE PA P.O. BOX 6248, PROVIDENCE, RI 02940 USA SN 0271-4132 BN 0-8218-3662-5 J9 CONTEMP MATH PY 2005 VL 383 BP 269 EP 283 PG 15 WC Mathematics SC Mathematics GA BDR59 UT WOS:000235105100016 ER PT S AU Geist, A AF Geist, A BE DiMartino, B Kranzlmuller, D Dongarra, J TI New directions in PVM/Harness research SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania AB The PVM development team continues to do distributed virtual machine research. Today that research revolves around the PVM project follow-on called Harness. Every three years the team chooses a new direction to explore. This year marks the beginning of a new cycle and this talk will describe the new directions and software that the PVM/Harness research team will developing over the next few years. The first direction involves the use of Harness technology in a DOE project to develop a scalable Linux OS suited to petascale computers. Harness distributed control will be leveraged to increase the fault tolerance of such an OS. The second direction involves the use of the Harness runtime environment in the new Open MPI software project. Open MPI is an integration of several previous MPI implementations, including LAM-MPI, the LA-MPI package, and the Fault Tolerant MPI from the Harness project. The third research direction is called the "Harness Workbench" and will investigate the creation of a unified and adaptive application development environment across diverse computing platforms. This research effort will leverage the dynamic plug-in technology developed in our Harness research. Each of these three research efforts will be described in detail. Finally the talk will describe the latest news on DOE's National Leadership Computing Facility, which will house a 100 TF Cray system at ORNL, and an IBM Blue Gene system at Argonne National Lab. We will describe the scientific missions of this facility and the new concept of "computational end stations" being pioneered by the Facility. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Geist, A (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. EM gst@ornl.gov NR 5 TC 0 Z9 0 U1 1 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 1 EP 3 PG 3 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700001 ER PT S AU Gropp, WD AF Gropp, WD BE DiMartino, B Kranzlmuller, D Dongarra, J TI Towards a productive MPI environment SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Gropp, WD (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM gropp@mcs.anl.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 4 EP 4 PG 1 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700002 ER PT S AU Lusk, E AF Lusk, E BE DiMartino, B Kranzlmuller, D Dongarra, J TI Components of systems software for parallel systems SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Lusk, E (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 5 EP 5 PG 1 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700003 ER PT S AU Gropp, W Lusk, E AF Gropp, W Lusk, E BE DiMartino, B Kranzlmuller, D Dongarra, J TI Using MPI-2: A problem-based approach SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM gropp@mcs.anl.gov; lusk@mcs.anl.gov NR 0 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 8 EP 8 PG 1 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700006 ER PT S AU Latham, R Ross, R Thakur, R Toonen, B AF Latham, R Ross, R Thakur, R Toonen, B BE DiMartino, B Kranzlmuller, D Dongarra, J TI Implementing MPI-IO shared file pointers without file system support SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania AB The ROMIO implementation of the MPI-IO standard provides a portable infrastructure for use on top of any number of different underlying storage targets. These targets vary widely in their capabilities, and in some cases additional effort is needed within ROMIO to support all MPI-IO semantics. The MPI-2 standard defines a class of file access routines that use a shared file pointer. These routines require communication internal to the MPI-IO implementation in order to allow processes to atomically update this shared value. We discuss a technique that leverages MPI-2 one-sided operations and can be used to implement this concept without requiring any features from the underlying file system. We then demonstrate through a simulation that our algorithm adds reasonable overhead for independent accesses and very small overhead for collective accesses. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Latham, R (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM robl@mcs.anl.gov; rross@mcs.anl.gov; thakur@mcs.anl.gov; toonen@mcs.anl.gov OI Latham, Rob/0000-0002-5285-6375 NR 12 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 84 EP 93 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700015 ER PT S AU Liao, W Coloma, K Choudhary, A Ward, L AF Liao, W Coloma, K Choudhary, A Ward, L BE DiMartino, B Kranzlmuller, D Dongarra, J TI Cooperative write-behind data buffering for MPI I/O SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania DE write behind; MPI I/O; file consistency; data buffering; I/O thread AB Many large-scale production parallel programs often run for a very long time and require data checkpoint periodically to save the state of the computation for program restart and/or tracing the progress. Such a write-only pattern has become a dominant part of an application's I/O workload and implies the importance of its optimization. Existing approaches for write-behind data buffering at both file system and MPI I/O levels have been proposed, but challenges still exist for efficient design to maintain data consistency among distributed buffers. To address this problem, we propose a buffering scheme that coordinates the compute processes to achieve the consistency control. Different from other earlier work, our design can be applied to files opened in read-write mode and handle the patterns with mixed MPI collective and independent I/O calls. Performance evaluation using BTIO and FLASH IO benchmarks is presented, which shows a significant improvement over the method without buffering. C1 Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. Sandia Natl Labs, Scalable Comp Syst Dept, Livermore, CA 94550 USA. RP Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. RI Liao, Wei-keng/B-7247-2009; Choudhary, Alok/C-5486-2009 NR 16 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 102 EP 109 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700017 ER PT S AU Thakur, R Ross, R Latham, R AF Thakur, R Ross, R Latham, R BE DiMartino, B Kranzlmuller, D Dongarra, J TI Implementing byte-range locks using MPI one-sided communication SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania ID PARALLEL FILE SYSTEM AB We present an algorithm for implementing byte-range locks using MPI passive-target one-sided communication. This algorithm is useful in any scenario in which multiple processes of a parallel program need to acquire exclusive access to a range of bytes. One application of this algorithm is for implementing MPI-IO's atomic-access mode in the absence of atomicity guarantees from the underlying file system. Another application is for implementing data sieving, a technique for optimizing noncontiguous writes by doing an atomic read-modify-write of a large, contiguous block of data. This byte-range locking algorithm can be used instead of POSIX f cntl file locks on file systems that do not support f cntl locks, on file systems where f cntl locks are unreliable, and on file systems where f cntl locks perform poorly. Our performance results demonstrate that the algorithm has low overhead and significantly outperforms f cntl locks on NFS file systems on a Linux cluster and on a Sun SMP. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM thakur@mcs.ani.gov; rross@mcs.ani.gov; robi@mcs.ani.gov OI Latham, Rob/0000-0002-5285-6375 NR 11 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 119 EP 128 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700019 ER PT S AU Falzone, C Chan, A Lusk, E Gropp, W AF Falzone, C Chan, A Lusk, E Gropp, W BE DiMartino, B Kranzlmuller, D Dongarra, J TI Collective error detection for MPI collective operations SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania DE MPI; collective; errors; datatype; hashing AB An MPI profiling library is a standard mechanism for intercepting MPI calls by applications. Profiling libraries are so named because they are commonly used to gather performance data on MPI programs. Here we present a profiling library whose purpose is to detect user errors in the use of MPI's collective operations. While some errors can be detected locally (by a single process), other errors involving the consistency of arguments passed to MPI collective functions must be tested for in a collective fashion. While the idea of using such a profiling library does not originate here, we take the idea further than it has been taken before (we detect more errors) and offer an open-source library that can be used with any MPI implementation. We describe the tests carried out, provide some details of the implementation, illustrate the usage of the library, and present performance tests. C1 Univ Penn, Edinboro, PA 16444 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Falzone, C (reprint author), Univ Penn, Edinboro, PA 16444 USA. RI Dongarra, Jack/E-3987-2014; OI Gropp, William/0000-0003-2905-3029 NR 6 TC 9 Z9 9 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 138 EP 147 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700021 ER PT S AU Buntinas, D Gropp, W AF Buntinas, D Gropp, W BE DiMartino, B Kranzlmuller, D Dongarra, J TI Designing a common communication subsystem SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania AB Communication subsystems are used in high-performance parallel computing systems to abstract the lower network layer. By using a communication subsystem, an upper middleware library or run-time system can be more easily ported to different interconnects. By abstracting the network layer, however, the designer typically makes the communication subsystem more specialized for that particular middleware library, making it ineffective for supporting middleware for other programming models. In previous work we analyzed the requirements of various programming-model middleware and the communication subsystems that support such requirements. We found that although there are no mutually exclusive requirements, none of the existing communication subsystems can efficiently support the programming model middleware we considered. In this paper, we describe our design of a common communication subsystem, called CCS, that can efficiently support various programming model middleware. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM buntinas@mcs.anl.gov; gropp@mcs.anl.gov OI Gropp, William/0000-0003-2905-3029 NR 17 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 156 EP 166 PG 11 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700023 ER PT S AU Barrett, B Squyres, JM Lumsdaine, A Graham, RL Bosilca, G AF Barrett, B Squyres, JM Lumsdaine, A Graham, RL Bosilca, G BE DiMartino, B Kranzlmuller, D Dongarra, J TI Analysis of the component architecture overhead in open MPI SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania AB Component architectures provide a useful framework for developing an extensible and maintainable code base upon which large-scale software projects can be built. Component methodologies have only recently been incorporated into applications by the High Performance Computing community, in part because of the perception that component architectures necessarily incur an unacceptable performance penalty. The Open MPI project is creating a new implementation of the Message Passing Interface standard, based on a custom component architecture - the Modular Component Architecture (MCA) - to enable straightforward customization of a high-performance MPI implementation. This paper reports on a detailed analysis of the performance overhead in Open MPI introduced by the MCA. We compare the MCA-based implementation of Open MPI with a modified version that bypasses the component infrastructure. The overhead of the MCA is shown to be low, on the order of 1%, for both latency and bandwidth microbenchmarks as well as for the NAS Parallel Benchmark suite. C1 Indiana Univ, Open Syst Lab, Bloomington, IN 47405 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Tennessee, Innovat Comp Lab, Knoxville, TN 37996 USA. RP Barrett, B (reprint author), Indiana Univ, Open Syst Lab, Bloomington, IN 47405 USA. EM brbarret@osl.iu.edu; jsquyres@osl.iu.edu; lums@osl.iu.edu; rlgraham@lanl.gov; bosilca@cs.utk.edu NR 14 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 175 EP 182 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700025 ER PT S AU Rasmussen, CE Squyres, JM AF Rasmussen, CE Squyres, JM BE DiMartino, B Kranzlmuller, D Dongarra, J TI A case for new MPI Fortran bindings SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania AB The Fortran language has evolved substantially from the Fortran 77 bindings defined in the MPI-1 (Message Passing Interface) standard. Fortran 90 introduced interface blocks (among other items); subsequently, the MPI-2 standard defined Fortran 90 bindings with explicit Fortran interfaces to MPI routines. In this paper, we describe the Open MPI implementation of these two sets of Fortran bindings and point out particular issues related to them. In particular, we note that strong typing of the Fortran 90 MPI interfaces with user-choice buffers leads to an explosion of interface declarations; each choice buffer must be expanded to all possible combinations of Fortran type, kind, and array dimension. Because of this (and other reasons outlined in this paper), we propose a new set of Fortran MPI bindings that uses the intrinsic ISO(-)C(-)BINDING module in Fortran 2003. These new bindings will allow MPI interfaces to be defined in Fortran that directly invoke their corresponding MPI C implementation routines - no additional layer of software to marshall parameters between Fortran and C is required. C1 Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. Indiana Univ, Open Syst Lab, Bloomington, IN 47405 USA. RP Rasmussen, CE (reprint author), Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. EM crasmussen@lanl.gov; jsquyres@open-mpi.org NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 183 EP 190 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700026 ER PT S AU Castain, RH Woodall, TS Daniel, DJ Squyres, JM Barrett, B Fagg, GE AF Castain, RH Woodall, TS Daniel, DJ Squyres, JM Barrett, B Fagg, GE BE DiMartino, B Kranzlmuller, D Dongarra, J TI The Open Run-Time Environment (OpenRTE): A transparent multi-cluster environment for high-performance computing SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania AB The Open Run-Time Environment (OpenRTE)-a spin-off from the Open MPI project-was developed to support distributed high-performance computing applications operating in a heterogeneous environment. The system transparently provides support for interprocess communication, resource discovery and allocation, and process launch across a variety of platforms. In addition, users can launch their applications remotely from their desktop, disconnect from them, and reconnect at a later time to monitor progress. This paper will describe the capabilities of the OpenRTE system, describe its architecture, and discuss future directions for the project. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Indiana Univ, Bloomington, IN 47405 USA. Univ Tennessee, Knoxville, TN USA. RP Castain, RH (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 225 EP 232 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700031 ER PT S AU Desai, N Lusk, E Bradshaw, R AF Desai, N Lusk, E Bradshaw, R BE DiMartino, B Kranzlmuller, D Dongarra, J TI MPISH2: Unix integration for MPI programs SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania AB While MPI is the most common mechanism for expressing parallelism, MPI programs remain poorly integrated in Unix environments. We introduce MPISH2, an MPI process manager analogous to serial Unix shells. It provides better integration capabilities for MPI programs by providing a uniform execution mechanism for parallel and serial programs, exposing return codes and standard I/O stream information. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 333 EP 342 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700044 ER PT S AU Garcia, PE Fernandez, J Petrini, F Garcia, JM AF Garcia, PE Fernandez, J Petrini, F Garcia, JM BE DiMartino, B Kranzlmuller, D Dongarra, J TI Assessing MPI performance on QsNet(II) SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania ID NETWORK AB To evaluate the communication capabilities of clusters, we must take into account not only the interconnection network but also the system software. In this paper, we evaluate the communication capabilities of a cluster based on dual-Opteron SMP nodes interconnected with QsNet(II). In particular, we study the raw network performance, the ability of MPI to overlap computation and communication, and the appropriateness of the local operating systems to support parallel processing. Experimental results show a stable system with a really efficient communication subsystem which is able to deliver 875 MB/s unidirectional bandwidth, 1.6 mu sec: unidirectional latency, and up to 99.5% CPU availability while communication is in progress. C1 Univ Murcia, Dept Ingn & Tecnol Computadores, E-30071 Murcia, Spain. Los Alamos Natl Lab, CCS 3 Modeling Algorithms & Informat, Los Alamos, NM 87545 USA. RP Garcia, PE (reprint author), Univ Murcia, Dept Ingn & Tecnol Computadores, E-30071 Murcia, Spain. EM pablo.garcia@ditec.um.es; juanf@ditec.um.es; fabrizio@lanl.gov; jmgarcia@ditec.um.es NR 9 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 399 EP 406 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700051 ER PT S AU Gropp, W Thakur, R AF Gropp, W Thakur, R BE DiMartino, B Kranzlmuller, D Dongarra, J TI An evaluation of implementation options for MPI one-sided communication SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania ID OPERATIONS; SYNCHRONIZATION AB MPI defines one-sided communication operations-put, get, and accumulate-together with three different synchronization mechanisms that define the semantics associated with the initiation and completion of these operations. In this paper, we analyze the requirements imposed by the MPI Standard on any implementation of one-sided communication. We discuss options for implementing the synchronization mechanisms and analyze the cost associated with each. An MPI implementer can use this information to select the implementation method that is best suited (has the lowest cost) for a particular machine environment. We also report on experiments we ran on a Linux cluster and a Sun SMP to determine the gap between the performance that could be achievable and what is actually achieved with MPI. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Gropp, W (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM gropp@mcs.anl.gov; thakur@mcs.anl.gov RI Dongarra, Jack/E-3987-2014; OI Gropp, William/0000-0003-2905-3029 NR 14 TC 10 Z9 10 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 415 EP 424 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700053 ER PT S AU Brightwell, R AF Brightwell, R BE DiMartino, B Kranzlmuller, D Dongarra, J TI A comparison of three MPI implementations for Red Storm SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania DE MPI; Red Storm; XT3; portals; performance AB Cray Red Storm is a new distributed memory massively parallel computing platform designed to scale to tens of thousands of nodes. Red Storm has a custom network designed around the Cray SeaStar network interface and router. In this paper, we present an evaluation of three different MPI implementations for Red Storm: the vendor-supported MPICH2 implementation, and two other implementations based on MPICH 1.2.6. We discuss the differences in these implementations and show how various implementation strategies impact performance and scalability. C1 Sandia Natl Labs, Scalable Comp Syst, Albuquerque, NM 87185 USA. RP Brightwell, R (reprint author), Sandia Natl Labs, Scalable Comp Syst, POB 5800, Albuquerque, NM 87185 USA. EM rbbrigh@sandia.gov NR 12 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 425 EP 432 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700054 ER PT S AU Trinitis, C Schulz, M AF Trinitis, C Schulz, M BE DiMartino, B Kranzlmuller, D Dongarra, J TI 4(th) International Special Session on: Current trends in numerical simulation for parallel engineering environments ParSim 2005 SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 12th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 18-21, 2005 CL Sorrento, ITALY SP Parallel Virtual Machine & Message Passing Interface Users Grp, Second Univ Naples, Dipartimento Ingegneria Informaz, HP, IBM, Intel, Microsoft, Myricom, Quadrics, NEC, Centro Competenza ICT, Reg Campania C1 Tech Univ Munich, Lehrstuhl Rechnertech & Rechnerorg, Inst Informat, D-8000 Munich, Germany. Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA USA. RP Trinitis, C (reprint author), Tech Univ Munich, Lehrstuhl Rechnertech & Rechnerorg, Inst Informat, D-8000 Munich, Germany. EM Carsten.Trinitis@in.tum.de; schulzm@llnl.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-29009-5 J9 LECT NOTES COMPUT SC PY 2005 VL 3666 BP 502 EP 503 PG 2 WC Computer Science, Theory & Methods SC Computer Science GA BDF44 UT WOS:000233236700063 ER PT S AU Leung, LR Qian, Y AF Leung, L. Ruby Qian, Yun BE Wagener, T Franks, S Gupta, HV Bogh, E Bastidas, L Nobre, C Galvao, CDO TI Hydrological response to climate variability, climate change, and climate extreme in the USA: climate model evaluation and projections SO Regional Hydrological Impacts of Climatic Change - Impact Assessment and Decision Making SE IAHS PUBLICATION LA English DT Proceedings Paper CT International Symposium on Regional Hydrological Impacts of Climatic Variability and Change CY APR 03-09, 2005 CL Foz do Iguaco, BRAZIL SP Int Assoc Hydrol Sci, ICCLAS DE climate change; climate variability; dynamical downscaling; model evaluation ID WESTERN UNITED-STATES; PRECIPITATION AB Water resources are sensitive to climate variability and change; predictions of seasonal to interannual climate variations and projections of long-term climate trends can provide significant values in managing water resources. This study examines the control (1975-1995) and future (19952100) climate simulated by a global climate model (GCM) and a regional climate simulation driven by the GCM control simulation for the USA. Comparison of the regional climate simulation with observations across 13 subregions showed that the simulation captured the seasonality and the distributions of precipitation rate quite well. The GCM control and climate change simulations showed that, as a result of a 1% increase in greenhouse gas concentrations per year, there will be a warming of 2-3 degrees C across the USA from 2000 to 2100. Although precipitation is not projected to change during this century, the warming trend will increase evapotranspiration to reduce annual basin mean runoff over five subregions along the coastal and south-central USA. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Leung, LR (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. RI qian, yun/A-5056-2010; qian, yun/E-1845-2011 NR 9 TC 1 Z9 1 U1 0 U2 5 PU INT ASSOC HYDROLOGICAL SCIENCES PI WALLINGFORD PA INST OF HYDROLOGY, WALLINGFORD OX10 8BB, ENGLAND SN 0144-7815 BN 978-1-901502-08-4 J9 IAHS-AISH P PY 2005 VL 295 BP 37 EP 44 PG 8 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BGO21 UT WOS:000248930000005 ER PT S AU Thornberg, SM Hochrein, JM Padilla, TA Abraham, IC AF Thornberg, SM Hochrein, JM Padilla, TA Abraham, IC BE Tanner, DM Ramesham, R TI Nanoliter MEMS package gas sampling to determine hermeticity SO Reliability, Packaging, Testing, and Characterization of MEMS/MOEMS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability, Packaging, Testing, and Characterization of MEMS/MOEMS IV CY JAN 24-25, 2005 CL San Jose, CA SP SPIE DE MEMS; hermetic; gas; sampling; reliability; RGA; volume; microliter; nanoliter AB Maintaining the integrity of the internal atmosphere of a hermetic device is essential for long-term component reliability because it is within this environment that all internal materials age. As MEMS package sizes decrease with miniaturization, characterization of the internal atmosphere becomes increasingly difficult. Typical transistor metal cans (e.g., TO-5 type) and large MEMS devices have internal volumes of tenths of a milliliter. Last year, gas-sampling methods for smaller-sized MEMS packages were developed and successfully demonstrated on volumes as low as 3 microliters (package outside dimensions: similar to 1 x 2 x 5 mm). This year, we present gas sampling methods and results for a much smaller MEMS package having an internal volume of 30 nanoliters, two orders of magnitude lower than the previous small package. After entirely redesigning the previous sampling manifold, several of the 30 nanoliter MEMS were gas sampled successfully and results showed the intended internal gas atmosphere of nitrogen was sealed inside the package. The technique is a radical jump from previous methods because not only were these MEMS packages sampled, but also the gas from each package was analyzed dozens of times over the course of about 20 minutes. Additionally, alternate methods for gas analyses not using helium or fluorinert will be presented. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Thornberg, SM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5690-X J9 P SOC PHOTO-OPT INS PY 2005 VL 5716 BP 36 EP 41 DI 10.1117/12.601183 PG 6 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics SC Engineering; Instruments & Instrumentation; Materials Science; Optics GA BCE35 UT WOS:000228835200008 ER PT S AU Phinney, LM Klody, KA Sackos, JT Walraven, JA AF Phinney, LM Klody, KA Sackos, JT Walraven, JA BE Tanner, DM Ramesham, R TI Damage of MEMS thermal actuators heated by laser irradiation SO RELIABILITY, PACKAGING, TESTING, AND CHARACTERIZATION OF MEMS/MOEMS IV SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Reliability, Packaging, Testing, and Characterization of MEMS/MOEMS IV CY JAN 24-25, 2005 CL San Jose, CA SP SPIE DE MEMS thermal actuators; optical actuation; laser damage of MEMS ID BEAM ELECTROTHERMAL ACTUATORS AB Optical actuation of microelectromechanical systems (MEMS) is advantageous for applications for which electrical isolation is desired. Thirty-two polycrystalline silicon opto-thermal actuators, optically-powered MEMS thermal actuators, were designed, fabricated, and tested. The design of the opto-thermal actuators consists of a target for laser illumination suspended between angled legs that expand when heated, providing the displacement and force output. While the amount of displacement observed for the opto-thermal actuators was fairly uniform for the actuators, the amount of damage resulting from the laser heating ranged from essentially no damage to significant amounts of damage on the target. The likelihood of damage depended on the target design with two of the four target designs being more susceptible to damage. Failure analysis of damaged targets revealed the extent and depth of the damage. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800,MS 1310, Albuquerque, NM 87185 USA. EM lmphinn@sandia.gov NR 18 TC 7 Z9 7 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5690-X J9 PROC SPIE PY 2005 VL 5716 BP 81 EP 88 DI 10.1117/12.594408 PG 8 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics SC Engineering; Instruments & Instrumentation; Materials Science; Optics GA BCE35 UT WOS:000228835200013 ER PT S AU Morales, AM Brazzle, JD Crocker, RW Domeier, LA Goods, EB Hachman, JT Harnett, CK Hunter, MC Mania, SS Mosier, BP Simmons, BA AF Morales, AM Brazzle, JD Crocker, RW Domeier, LA Goods, EB Hachman, JT Harnett, CK Hunter, MC Mania, SS Mosier, BP Simmons, BA BE Tanner, DM Ramesham, R TI Fabrication and characterization of polymer microfluidic devices for bioagent detection SO Reliability, Packaging, Testing, and Characterization of MEMS/MOEMS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability, Packaging, Testing, and Characterization of MEMS/MOEMS IV CY JAN 24-25, 2005 CL San Jose, CA SP SPIE DE microfluidics; bioagent; injection molding; metrology. AB Sandia and Lawrence Livermore National Laboratories are developing a briefcase-sized, broad-spectrum bioagent detection system. This autonomous instrument, the BioBriefcase, will monitor the environment and warn against bacterium, virus, and toxin based biological attacks. At the heart of this device, inexpensive polymer microfluidic chips will carry out sample preparation and analysis. Fabrication of polymer microfluidic chips involves the creation of a master in etched glass; plating of the master to produce a nickel stamp; large lot chip replication by injection molding; and thermal chip sealing. Since the performance and reliability of microfluidic chips are very sensitive to fluidic impedance and to electromagnetic fluxes, the microchannel dimensions and shape have to be tightly controlled during chip fabrication. In this talk, we will present an overview of chip design and fabrication. Metrology data collected at different fabrication steps and the dimensional deviations of the polymer chip from the original design will be discussed. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Morales, AM (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. OI Simmons, Blake/0000-0002-1332-1810 NR 5 TC 3 Z9 3 U1 0 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5690-X J9 P SOC PHOTO-OPT INS PY 2005 VL 5716 BP 89 EP 94 DI 10.1117/12.592802 PG 6 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics SC Engineering; Instruments & Instrumentation; Materials Science; Optics GA BCE35 UT WOS:000228835200014 ER PT S AU Walraven, JA Cole, EI Barr, D Anderson, RE Kilgo, A Maciel, J Morrison, R Karabudak, NN AF Walraven, JA Cole, EI Barr, D Anderson, RE Kilgo, A Maciel, J Morrison, R Karabudak, NN BE Tanner, DM Ramesham, R TI Backside preparation and failure analysis for packaged microelectromechanical systems (MEMS) SO Reliability, Packaging, Testing, and Characterization of MEMS/MOEMS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability, Packaging, Testing, and Characterization of MEMS/MOEMS IV CY JAN 24-25, 2005 CL San Jose, CA SP SPIE DE MEMS; failure analysis; MEMS backside sample preparation; TIVA AB Failure analysis tools and techniques that identify root cause failure mechanisms are key components to improving MEMS technology. Failure analysis and characterization are relatively simple at the wafer and die level where chip access is straightforward. However, analysis and characterization of packaged parts or components encapsulated with covers, caps, etc may be more cumbersome and lead to problems assessing the root cause of failure. This paper will discuss two methods used to prepare the backside of the package/device to allow for failure analysis and inspection of different MEMS components without removing the cap, cover, or lid on the device and/or the package. One method for backside preparation was grinding and polishing the package for IR inspection. This method involved backfilling the package cavity with epoxy to hold the die in place. The other method involved opening a window through the backside of the package, exposing the die for IR inspection. Failure analysis results showed both methods of backside preparation were successful in revealing the failure mechanisms on two different MEMS technologies. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Walraven, JA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 1 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5690-X J9 P SOC PHOTO-OPT INS PY 2005 VL 5716 BP 165 EP 172 DI 10.1117/12.600794 PG 8 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics SC Engineering; Instruments & Instrumentation; Materials Science; Optics GA BCE35 UT WOS:000228835200023 ER PT J AU Lamoreaux, SK AF Lamoreaux, SK TI The Casimir force: background, experiments, and applications SO REPORTS ON PROGRESS IN PHYSICS LA English DT Review ID VAN-DER-WAALS; MU-M RANGE; EVANESCENT ELECTROMAGNETIC-WAVES; ZERO-POINT ENERGY; VANDERWAALS FORCES; MICROELECTROMECHANICAL SYSTEMS; QUANTUM-MECHANICS; ATTRACTIVE FORCES; LIFSHITZ THEORY; LIQUID-HELIUM AB The Casimir force, which is the attraction of two uncharged material bodies due to modification of the zero-point energy associated with the electromagnetic modes in the space between them, has been measured with per cent-level accuracy in a number of recent experiments. A review of the theory of the Casimir force and its corrections for real materials and finite temperature are presented in this report. Applications of the theory to a number of practical problems are discussed. C1 Los Alamos Natl Lab, Div Phys P23, Los Alamos, NM 87545 USA. RP Lamoreaux, SK (reprint author), Los Alamos Natl Lab, Div Phys P23, MS H803, Los Alamos, NM 87545 USA. NR 132 TC 331 Z9 334 U1 10 U2 54 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0034-4885 J9 REP PROG PHYS JI Rep. Prog. Phys. PD JAN PY 2005 VL 68 IS 1 BP 201 EP 236 DI 10.1088/0034-4885/68/1/R04 PG 36 WC Physics, Multidisciplinary SC Physics GA 910KB UT WOS:000227928900004 ER PT S AU Liu, XM Balakireva, L Hochstenbach, P Van de Sompel, H AF Liu, XM Balakireva, L Hochstenbach, P Van de Sompel, H BE Rauber, A Christodoulakis, S Tjoa, AM TI File-based storage of digital objects and constituent datastreams: XMLtapes and Internet archive ARC files SO RESEARCH AND ADVANCED TECHNOLOGY FOR DIGITAL LIBRARIES SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 9th European Conference on Research and Advanced Technology for Digital Libraries (ECDL 2005) CY SEP 18-23, 2005 CL Vienna, AUSTRIA SP Austrian Natl Lib, Austrian Comp Soc, Vienna Univ Technol AB This paper introduces the write-once/read-many XMLtape/ARC storage approach for Digital Objects and their constituent datastreams. The approach combines two interconnected file-based storage mechanisms that are made accessible in a protocol-based manner. First, XML-based representations of multiple Digital Objects are concatenated into a single file named an XMLtape. An XMLtape is a valid XML file; its format definition is independent of the choice of the XML-based complex object format by which Digital Objects are represented. The creation of indexes for both the identifier and the creation datetime of the XML-based representation of the Digital Objects facilitates OAI-PMH-based access to Digital Objects stored in an XMLtape. Second, ARC files, as introduced by the Internet Archive, are used to contain the constituent datastreams of the Digital Objects in a concatenated manner. An index for the identifier of the datastream facilitates OpenURL-based access to an ARC file. The interconnection between XMLtapes and ARC files is provided by conveying the identifiers of ARC files associated with an XMLtape as administrative information in the XMLtape, and by including OpenURL references to constituent datastreams of a Digital Object in the XML-based representation of that Digital Object. C1 Los Alamos Natl Lab, Res Lib, Los Alamos, NM 87544 USA. Univ Ghent, Univ Lib, B-9000 Ghent, Belgium. RP Los Alamos Natl Lab, Res Lib, Los Alamos, NM 87544 USA. EM liu_x@lanl.gov; ludab@lanl.gov; Patrick.Hochstenbach@ugent.be; herbertv@lanl.gov NR 18 TC 0 Z9 0 U1 1 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-28767-1 J9 LECT NOTES COMPUT SC PY 2005 VL 3652 BP 254 EP 265 PG 12 WC Computer Science, Information Systems; Computer Science, Theory & Methods; Information Science & Library Science SC Computer Science; Information Science & Library Science GA BDJ77 UT WOS:000233890800023 ER PT S AU Nelson, ML de Sompel, HV Liu, XM Harrison, TL McFarland, N AF Nelson, ML de Sompel, HV Liu, XM Harrison, TL McFarland, N BE Rauber, A Christodoulakis, S Tjoa, AM TI mod_oai: An apache module for metadata harvesting SO RESEARCH AND ADVANCED TECHNOLOGY FOR DIGITAL LIBRARIES SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 9th European Conference on Research and Advanced Technology for Digital Libraries (ECDL 2005) CY SEP 18-23, 2005 CL Vienna, AUSTRIA SP Austrian Natl Lib, Austrian Comp Soc, Vienna Univ Technol AB We describe mod_oai, an Apache 2.0 module that implements the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH). OAI-PMH is the de facto standard for metadata exchange in digital libraries and allows repositories to expose their contents in a structured, application-neutral format with semantics optimized for accurate incremental harvesting. mod_oai differs from other OAI-PMH implementations in that it optimizes harvesting web content by building OAI-PMH capability into the Apache server. C1 Old Dominion Univ, Dept Comp Sci, Norfolk, VA 23508 USA. Los Alamos Natl Lab, Res Lab, Los Alamos, NM 87545 USA. RP Nelson, ML (reprint author), Old Dominion Univ, Dept Comp Sci, Norfolk, VA 23508 USA. EM mln@cs.odu.edu; herbertv@lanl.gov; liu_x@lanl.gov; tharriso@cs.odu.edu; mncfarl@lanl.gov OI Nelson, Michael/0000-0003-3749-8116 NR 4 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-28767-1 J9 LECT NOTES COMPUT SC PY 2005 VL 3652 BP 509 EP 510 PG 2 WC Computer Science, Information Systems; Computer Science, Theory & Methods; Information Science & Library Science SC Computer Science; Information Science & Library Science GA BDJ77 UT WOS:000233890800058 ER PT J AU Tao, J Daniele, J Hummel, E Goldheim, D Slowinski, G AF Tao, J Daniele, J Hummel, E Goldheim, D Slowinski, G TI Developing an effective strategy for managing intellectual assets SO RESEARCH-TECHNOLOGY MANAGEMENT LA English DT Article DE intellectual asset management; strategy; technology valuation AB Although many companies today are exploring ways to extract value from their patent portfolios, most use ad hoc approaches that are inefficient and lead to disappointing results. Leading firms, on the other hand, take a proactive approach and systematically tie their intellectual asset management strategy to the core strategies of the firm. A study of more than 70 firms illuminates two key aspects of this approach: how to strategically organize the firm's intellectual asset portfolio and how to extract value from that portfolio. This article describes how firms strategically organize their intellectual assets to maximize their value to the firm. A subsequent article will describe specific methods firms use to extract value from their intellectual asset portfolio. C1 Air Prod & Chem Inc, Allentown, PA USA. Acorn Technol, La Jolla, CA USA. Bell Labs, Business Dev, Murray Hill, NJ 07974 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Rutgers State Univ, Sch Business, Newark, NJ 07102 USA. RP Tao, J (reprint author), Air Prod & Chem Inc, Allentown, PA USA. EM taojc@apci.com; daniele@acorntech.com; ehummel@lucent.com; dlgoldh@sandia.gov; gene@strategicalliance.com NR 1 TC 6 Z9 6 U1 1 U2 7 PU INDUSTRIAL RESEARCH INST INC PI WASHINGTON PA 1550 M ST., NW, WASHINGTON, DC 20005 USA SN 0895-6308 J9 RES TECHNOL MANAGE JI Res.-Technol. Manage. PD JAN-FEB PY 2005 VL 48 IS 1 BP 50 EP 58 PG 9 WC Business; Engineering, Industrial; Management SC Business & Economics; Engineering GA 885AY UT WOS:000226129500012 ER PT S AU Almer, JD Swift, GA Nychka, JA Ustundag, E Clarke, DR AF Almer, JD Swift, GA Nychka, JA Ustundag, E Clarke, DR BE Denis, S Hanabusa, T He, BP Mittemeijer, E Nan, J Noyan, IC Scholtes, B Tanaka, K Xu, KW TI In situ synchrotron measurements of oxide growth strains SO RESIDUAL STRESSES VII, PROCEEDINGS SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference onResidual Strsses (ICRS-7) CY JUN 14-17, 2004 CL Xian, PEOPLES R CHINA SP Chinese Mech Engn Soc, Xian Jiaotong Univ C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Almer, JD (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. EM almer@aps.anl.gov RI Clarke, David/D-2616-2009; Ustundag, Ersan/C-1258-2009; Albe, Karsten/F-1139-2011 OI Ustundag, Ersan/0000-0002-0812-7028; NR 0 TC 1 Z9 1 U1 0 U2 3 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-969-5 J9 MATER SCI FORUM PY 2005 VL 490-491 BP 287 EP 293 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA BCN68 UT WOS:000230305200052 ER PT S AU Telschow, KL AF Telschow, KL BE Thompson, DO Chimenti, DE TI Laser acoustic imaging of film bulk acoustic resonator (FBAR) lateral mode dispersion SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines ID GUIDED-WAVES AB A laser acoustic imaging microscope has been developed that measures acoustic motion with high spatial resolution without scanning. Images are recorded at normal video frame rates and heterodyne principles are used to allow operation at any frequency from Hz to GHz. Fourier transformation of the acoustic amplitude and phase displacement images provides a direct quantitative determination of excited mode wavenumbers at any frequency. Results are presented at frequencies near the first longitudinal thickness mode (similar to 900 MHz) demonstrating simultaneous excitation of lateral modes with nonzero wavenumbers in an electrically driven AlN thin film acoustic resonator. Images combined at several frequencies form a direct visualization of lateral mode dispersion relations for the device under test allowing mode identification and a direct measure of specific lateral mode properties. Discussion and analysis of the results are presented in comparison with plate wave modeling of these devices taking account for material anisotropy and multilayer films. C1 Idaho Natl Engn & Environm Lab, Phys Grp, Idaho Falls, ID 83415 USA. RP Telschow, KL (reprint author), Idaho Natl Engn & Environm Lab, Phys Grp, Idaho Falls, ID 83415 USA. NR 11 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 251 EP 256 PG 6 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893300031 ER PT S AU Johnson, PA Sutin, A AF Johnson, PA Sutin, A BE Thompson, DO Chimenti, DE TI Nonlinear elastic wave NDE I. Nonlinear resonant ultrasound spectroscopy and slow dynamics diagnostics SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines ID ACOUSTIC HARMONIC-GENERATION; ROCK AB The nonlinear elastic response of materials (e.g., wave mixing, harmonic generation) is much more sensitive to the presence of damage than the linear response (e.g., wavespeed, dissipation). An overview of the four primary Nonlinear Elastic Wave Spectroscopy (NEWS) methods used in nonlinear damage detection are presented in this and the following paper. Those presented in this paper are Nonlinear Resonant Ultrasound Spectroscopy (NRUS), based on measurement of the nonlinear response of one or more resonant modes in a test sample, and Slow Dynamics Diagnostics (SDD), manifest by an alteration in the material dissipation and elastic modulus after application of relatively high-amplitude wave that slowly recovers in time. C1 Los Alamos Natl Lab, Geophys Grp, Los Alamos, NM 87545 USA. RP Johnson, PA (reprint author), Los Alamos Natl Lab, Geophys Grp, POB 1663, Los Alamos, NM 87545 USA. NR 17 TC 1 Z9 1 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 377 EP 384 PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893300047 ER PT S AU Sun, JG Benz, J AF Sun, JG Benz, J BE Thompson, DO Chimenti, DE TI Flash duration effect in one-sided thermal imaging SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines AB A theoretical formulation is developed for one-sided thermal imaging that utilizes an infrared camera for temperature measurement and photographic flash lamps for radiant heating of the sample surface. This formulation accounts for the radiant intensity variation of flash lamps, which typically exhibit a short rise time but a long exponential-decay time (several milliseconds). During the flash, the infrared camera receives radiation from the emission of the sample surface as well as the reflection of the flash energy. Experimental results clearly show the flash-reflection effect and the temperature response of the sample surface under finite flash durations. Theoretical and experimental data are compared and discussed. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Sun, JG (reprint author), Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 650 EP 654 PG 5 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893300083 ER PT S AU Aufderheide, MB Barty, A Martz, HE AF Aufderheide, MB Barty, A Martz, HE BE Thompson, DO Chimenti, DE TI Simulation of phase effects in imaging for mesoscale NDE SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines ID HARD X-RAYS; SYNCHROTRON-RADIATION; CONTRAST AB High energy density experiments, such as those planned at the National Ignition Facility (NIF), use mesoscale targets with the goals of studying high energy density physics, inertial confinement fusion, and the support of national security needs. Mesoscale targets are typically several millimeters in size and have complex micrometer-sized structures composed of high-density metals and low-density foams and ices. These targets are designed with exacting tolerances that are difficult to achieve at present. Deviation from these tolerances can result in compromise of experimental goals and thus it is necessary to determine as-built properties of these targets using NDE techniques. Radiography and computed tomography are being used to investigate these targets, but the mix between phase and absorption information is difficult to separate, making interpretation of results difficult. We have recently improved the HADES radiographic simulation code to include phase in simulations, as an aid for doing NDE on mesoscale targets. In this paper we report on how we extended HADES to incorporate phase effects, and compare simulations with a variety of experimental test results. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Aufderheide, MB (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 21 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 663 EP 670 PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893300085 ER PT S AU Zavaljevski, N Bakhtiari, S Miron, A Kupperman, DS Wei, TYC Marchertas, P AF Zavaljevski, N Bakhtiari, S Miron, A Kupperman, DS Wei, TYC Marchertas, P BE Thompson, DO Chimenti, DE TI Automated algorithms for eddy current array probes for steam generator inspection SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines AB Eddy current array probes have recently been introduced for the inspection of steam generator tubes. Efficient analysis of the acquired data requires automated algorithms. We describe the Automated Nondestructive Testing Array Evaluation System, a software tool for detecting and characterizing degradation of steam generator tubing from array probe data. Defect detection is based on the sequential probability ratio test and image processing algorithms. The maximum depth of each defect is determined by using nonlinear regression, the estimated amplitude and phase at selected frequencies, and a set of heuristic rules. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Zavaljevski, N (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 728 EP 735 PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893300093 ER PT S AU Jones, RW Sweterlitsch, JJ Wagner, AJ McClelland, JF Hsu, DK Polis, DL Sovinski, MF AF Jones, RW Sweterlitsch, JJ Wagner, AJ McClelland, JF Hsu, DK Polis, DL Sovinski, MF BE Thompson, DO Chimenti, DE TI FT-IR photoacoustic spectroscopy applied to the curing and aging of composites SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines AB Fourier-transform infrared photoacoustic spectroscopy has been applied to carbon-fiber composites to test whether bulk physical properties of the composites could be determined using the near-surface-sensitive photoacoustic approach. Both the cure levels of carbon fiber/cyanate ester composites and the interlaminar shear strengths of artificially aged carbon fiber/epoxy composites were successully measured. Standard errors of cross validation were 3.46% cure for a sample set ranging from 8% to 95% Cured and 1.60 MPa for aged samples with strengths ranging from 22 to 77 MPa. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Jones, RW (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 9 TC 1 Z9 1 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 1094 EP 1099 PG 6 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893301006 ER PT S AU Reverdy, F Hopkins, D AF Reverdy, F Hopkins, D BE Thompson, DO Chimenti, DE TI Inspection of spot welds using a portable ultrasonic phased-array system SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines AB Results were presented last year to demonstrate the feasibility of using an ultrasonic phased array to inspect spot welds. Analysis of the signals in the Fourier domain allows identification of satisfactory, undersized and defective welds. Signal- and image-processing techniques have been implemented with the goal of extracting the dimensions of the weld nugget. The results presented here were obtained using a portable phased-array controller. Toward developing a fully portable system, a housing for the probe is under development with an integrated mechanical scanning system. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Reverdy, F (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Rd,MS 46A-1123, Berkeley, CA 94720 USA. NR 6 TC 3 Z9 4 U1 2 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 1212 EP 1219 PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893301022 ER PT S AU Crawford, SL Pardini, AF AF Crawford, SL Pardini, AF BE Thompson, DO Chimenti, DE TI The remotely operated nondestructive examination system for examining the knuckle region of Hanford's double shell waste tanks SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines AB The Pacific Northwest National Laboratory has developed a technology to address the examination requirements associated with the knuckle region of Hanford's double shell waste tanks. This examination poses a significant technical challenge because the area that requires examination is in a confined space, high radiation region and is not accessible using conventional measurement techniques. This paper describes the development, deployment and modification of the remotely operated nondestructive examination (RONDE) system that utilizes a technique known as Synthetic Aperture Focusing (SAFT). The system detects stress corrosion cracking in the high stress region of the knuckle and characterizes the crack with tandem SAFT. PNNL has qualified the system to perform inspections on the entire knuckle region of Hanford's double she]] waste tanks. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Crawford, SL (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 1661 EP 1668 PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893301081 ER PT S AU Greenwood, MS Adamson, JD Bond, LJ AF Greenwood, MS Adamson, JD Bond, LJ BE Thompson, DO Chimenti, DE TI Measurement of the viscosity-density product using a quartz wedge SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines AB The on-line measurement of the viscosity-density product is accomplished by analyzing the multiple reflections of an ultrasonic shear horizontal (SH) wave within a quartz wedge. Many echoes are observed as the ultrasound is reflected from the two sides (inclined at a 70 degrees angle) and the quartz-liquid interface at the base of the wedge. The analysis yields a very accurate measurement of the reflection coefficient. The measurement is self-calibrating because it is not affected by changes in the pulser voltage. C1 Pacific NW Natl Lab, Richland, WA 99354 USA. RP Greenwood, MS (reprint author), Pacific NW Natl Lab, Richland, WA 99354 USA. OI Adamson, Justus/0000-0002-7868-5631 NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 1690 EP 1697 PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893301085 ER PT S AU Ridgway, P Russo, R Lafond, E Jackson, T Zhang, X AF Ridgway, P Russo, R Lafond, E Jackson, T Zhang, X BE Thompson, DO Chimenti, DE TI A sensor for laser ultrasonic measurement of elastic properties of moving paper SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines ID ONLINE MEASUREMENT; MECHANICAL-PROPERTIES; STRENGTH; WAVES AB An automated, non-contact, non-destructive sensor has been developed for measurement of sheet flexural and shear rigidity in paper manufacturing. It was tested on a pilot web handier at web speeds up to 25.4 m/s. A model equation was fitted to the frequency dependence of the phase velocity of A. mode Lamb waves. Ultrasound was generated in paper with a pulsed Nd:YAG laser and detected with a Mach-Zehnder interferometer coupled with a scanning mirror/timing system to compensate for paper motion. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ridgway, P (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd MS 70-108B, Berkeley, CA 94720 USA. NR 18 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 1698 EP 1705 PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893301086 ER PT S AU Greenwood, MS Brodsky, A Burgess, L Hamad, M Bond, LJ AF Greenwood, MS Brodsky, A Burgess, L Hamad, M Bond, LJ BE Thompson, DO Chimenti, DE TI Observing effects of particle size for a slurry using ultrasonic diffraction grating spectroscopy SO Review of Progress in Quantitative Nondestructive Evaluation, Vols 24A and 24B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 31st Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 25-30, 2004 CL Colorado Sch Mines, Golden, CO HO Colorado Sch Mines ID LIGHT-REFLECTION SPECTROSCOPY AB The ultrasonic diffraction gritting is formed by machining triangular grooves, 240 microns apart, on the flat surface of a stainless steel (SS) half-cylinder. Ultrasound from a send transducer travels through the SS and strikes the back of the grating where it is reflected to a receive transducer. A peak in the receive signal is used to determine the velocity of sound and observe effects of particle size. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Greenwood, MS (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0245-0 J9 AIP CONF PROC PY 2005 VL 760 BP 1729 EP 1736 PG 8 WC Acoustics; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Acoustics; Engineering; Materials Science; Optics GA BCE68 UT WOS:000228893301090 ER PT J AU Baer, BJ Yoo, CS AF Baer, BJ Yoo, CS TI Laser heated high density fluids probed by coherent anti-Stokes Raman spectroscopy SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID LIQUID CARBON-MONOXIDE; NITROGEN; MIXTURES; TEMPERATURES; OXYGEN AB We describe experiments integrating coherent anti-Stokes Raman spectroscopy (CARS), laser-heating and diamond-anvil cell (DAC) technologies for probing molecular vibrations of transparent molecular fluids at the pressure-temperature conditions of energetic detonation and interiors of giant planets. In these experiments, we use a microfabricated metal toroid and a cw Nd:YLF laser to conductively heat a surrounding transparent sample in a DAC. The laser is operated at a TEM01* mode to match the shape of the toroid and thus produces a uniform heating area. The CARS probe utilizes two pulsed lasers with similar cavity lengths: a commercial narrow-band mode-locked Q-switched Nd:YAG laser and a homebuilt broadband dye laser. A strong CARS signal is then produced from the sample in the central region of laser-heated metal toroid where the two laser pulses spatially and temporally coincide. In this article, we demonstrate that this technique is capable of producing high quality vibrational spectra from nitrogen fluid above 2000 K and 13 GPa, where the application of spontaneous Raman spectroscopy is limited because of intense thermal radiation. (C) 2005 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Div H, Livermore, CA 94550 USA. RP Baer, BJ (reprint author), Lawrence Livermore Natl Lab, Div H, Livermore, CA 94550 USA. NR 12 TC 3 Z9 3 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2005 VL 76 IS 1 AR 013907 DI 10.1063/1.1819874 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 893SA UT WOS:000226738300031 ER PT J AU Ham, JE Durham, B Scott, JR AF Ham, JE Durham, B Scott, JR TI Design of instrumentation for probing changes in electrospray droplets via the Stern-Volmer relationship SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID LASER-INDUCED FLUORESCENCE; RUTHENIUM(II) POLYPYRIDINE COMPLEXES; MASS-SPECTROMETRY; GAS-PHASE; ION FORMATION; PROTEINS; WATER; TRISBIPYRIDINE; SPECTROSCOPY; CHEMISTRY AB Electrospray ionization (ESI) is a proven method for introducing large intact molecules into the gas phase. However, the processes that occur within this ion source are poorly understood. We have developed instrumentation and methodology to probe the evolution of droplets within the electrospray plume. Using emission lifetime spectroscopy, excited-state lifetimes of [Ru(bpy)(3)](2+) with and without a known quencher, 2,3,5,6-tetramethyl-p-phenlyenediamine, present were observed. Lifetimes were shown to decrease as quencher concentration increased, as expected. Rate constants (with and without quencher present) were determined and correlated with quencher concentration using the Stern-Volmer relationship. Stern-Volmer plots reveal the linearity of the quenching reaction and can be used to determine the concentrations of species within the electrosprayed droplets. The evolution of the ESI droplets can be probed by comparing the concentration of a species at different locations within the plume. (C) 2005 American Institute of Physics. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Univ Arkansas, Dept Chem & Biochem, Fayetteville, AR 72701 USA. RP Scott, JR (reprint author), Idaho Natl Engn & Environm Lab, 2525 N Fremont Ave, Idaho Falls, ID 83415 USA. EM scotjr@inel.gov RI Scott, Jill/G-7275-2012 NR 38 TC 3 Z9 3 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2005 VL 76 IS 1 AR 014101 DI 10.1063/1.1823191 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 893SA UT WOS:000226738300035 ER PT J AU Partouche-Sebban, D Holtkamp, DB Rodriguez, P Stone, JB Borror, SD Kruschwitz, CA Young, JA AF Partouche-Sebban, D Holtkamp, DB Rodriguez, P Stone, JB Borror, SD Kruschwitz, CA Young, JA TI Alternative calibration techniques for high-speed pyrometers in shock experiments SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID BISMUTH AB Optical pyrometry is widely used in industry and research laboratories to perform surface temperature measurements of sample materials. These shock physics experiments are normally conducted at powder or gas gun facilities or at facilities where high explosives can be used as a shock wave source, and using high-speed pyrometers that are usually calibrated by using a blackbody source. But, electrical power, time, and space can be limiting factors in such facilities, and blackbody calibration can be difficult. Crucial parts of the experimental setup (fibers, lenses, and/or mirrors) are destroyed in such experiments, and the pyrometry system must be recalibrated before each experiment. We have developed a calibration technique using integrating-sphere sources that allows us to calibrate pyrometers more rapidly and easily than with blackbodies. Two different integrating-sphere systems are described to cover the wavelength range generally used in pyrometry studies. The characterization of these systems is fully detailed including measurements of their spectral radiances. A discussion of the advantages and drawbacks of both calibration sources is given. (C) 2005 American Institute of Physics. C1 Commissariat Energie Atom, F-91680 Bruyeres Le Chatel, France. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Los Alamos Operat, Bechtel Nevada, Los Alamos, NM 87544 USA. RP Partouche-Sebban, D (reprint author), Commissariat Energie Atom, F-91680 Bruyeres Le Chatel, France. EM david.partouche@cea.fr NR 4 TC 4 Z9 5 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2005 VL 76 IS 1 AR 013106 DI 10.1063/1.1833331 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 893SA UT WOS:000226738300006 ER PT J AU Rudakov, DL Boedo, JA Moyer, RA Stangeby, PC McLean, A Watkins, JG AF Rudakov, DL Boedo, JA Moyer, RA Stangeby, PC McLean, A Watkins, JG TI Effect of electron temperature fluctuations on slowly swept Langmuir probe measurements (vol 75, art no 4334, 2004) SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Correction C1 Univ Calif San Diego, Energy Res Ctr, La Jolla, CA 92093 USA. Univ Toronto, Inst Aerosp Studies, Toronto, ON M3H 5T6, Canada. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Rudakov, DL (reprint author), Univ Calif San Diego, Energy Res Ctr, La Jolla, CA 92093 USA. EM rudakov@fusion.gat.com NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2005 VL 76 IS 1 AR 019901 DI 10.1063/1.1849512 PG 1 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 893SA UT WOS:000226738300057 ER PT S AU Faulon, JL Visco, DP Roe, D AF Faulon, JL Visco, DP Roe, D BE Lipkowitz, KB Larter, R Cundari, TR TI Enumerating molecules SO REVIEWS IN COMPUTATIONAL CHEMISTRY, VOL 21 SE Reviews in Computational Chemistry LA English DT Article; Book Chapter ID ASSISTED STRUCTURE ELUCIDATION; AUTOMATED STRUCTURE ELUCIDATION; ACTIVITY RELATIONSHIP MODELS; COMBINATORIAL LIBRARY DESIGN; EXTENDED VALENCE SEQUENCES; NUCLEAR-MAGNETIC-RESONANCE; HARARY READ NUMBERS; DARC-EPIOS METHOD; EXHAUSTIVE GENERATION; CONSTANT NUMBER C1 Sandia Natl Labs, Computat Biol Dept, Livermore, CA 94551 USA. Tennessee Technol Univ, Dept Chem Engn, Cookeville, TN 38502 USA. Sandia Natl Labs, Biosyst Res Dept, Livermore, CA 94551 USA. RP Sandia Natl Labs, Computat Biol Dept, POB 969,MS 9951, Livermore, CA 94551 USA. NR 245 TC 27 Z9 27 U1 3 U2 15 PU WILEY-VCH, INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1069-3599 BN 0-471-68239-X J9 REV COMP CH JI Rev. Comput. Chem. PY 2005 VL 21 BP 209 EP 286 DI 10.1002/0471720895.ch3 D2 10.1002/0471720895 PG 78 WC Chemistry, Multidisciplinary SC Chemistry GA BCP94 UT WOS:000230643500003 ER PT J AU Herwig, F AF Herwig, Falk BE Roser, S TI The Second Stars SO REVIEWS IN MODERN ASTRONOMY 18: FROM COSMOLOGICAL STRUCTURES TO THE MILKY WAY LA English DT Article; Book Chapter ID ASYMPTOTIC GIANT BRANCH; INTERMEDIATE-MASS STARS; METAL-POOR STARS; S-PROCESS NUCLEOSYNTHESIS; DEFICIENT CENTRAL STARS; VERY-LOW METALLICITY; AGB STARS; CARBON STARS; STELLAR EVOLUTION; SAKURAIS OBJECT AB The ejecta of the first probably very massive stars polluted the Big Bang primordial element mix with the first heavier elements. The resulting ultra metal-poor abundance distribution provided the initial conditions for the second stars of a wide range of initial masses reaching down to intermediate and low masses. The importance of these second stars for understanding the origin of the elements in the early universe are manifold. While the massive first stars have long vanished the second stars are still around and currently observed. They are the carriers of the information about the first stars, but they are also capable of nuclear production themselves. For example, in order to use ultra or extremely metal-poor stars as a probe for the r process in the early universe a reliable model of the s process in the second stars is needed. Eventually, the second stars may provide us with important clues on questions ranging from structure formation to how the stars actually make the elements, not only in the early but also in the present universe. In particular the C-rich extremely metal-poor stars, most of which show the s-process signature, are thought to be associated with chemical yields from the evolved giant phase of intermediate mass stars. Models of such AGB stars at extremely low metallicity now exist, and comparison with observation show important discrepancies, for example with regard to the synthesis of nitrogen. This may hint at burning and mixing aspects of extremely metal-poor evolved stars that are not yet included in the standard picture of evolution, as for example the hydrogen-ingestion flash. The second stars of intermediate mass may have also played an important role in the formation of heavy elements that form through slow neutron capture reaction chains (s process). Comparison of models with observations reveal which aspects of the physics input and assumptions need to be improved. The s process is a particularly useful diagnostic tool for probing the physical processes that are responsible for the creation of elements in stars, like for example rotation. As new observational techniques and strategies continue to penetrate the field, for example the multi-object spectroscopy, or the future spectroscopic surveys, the extremely metal-poor stars will play an increasingly important role to address some of the most fundamental and challenging, current questions of astronomy. C1 Los Alamos Natl Lab, Theoret Astrophys Grp, Los Alamos, NM 87544 USA. RP Herwig, F (reprint author), Los Alamos Natl Lab, Theoret Astrophys Grp, POB 1663, Los Alamos, NM 87544 USA. EM fherwig@lanl.gov NR 87 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL SCIENCE PUBL PI OXFORD PA OSNEY MEAD, OXFORD OX2 0EL, ENGLAND BN 978-3-52760-896-6 PY 2005 BP 21 EP 47 D2 10.1002/3527608966 PG 27 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BAD00 UT WOS:000303827200003 ER PT J AU Biegon, A Schiffer, WK Ding, Y Wu, H Pareto, D Lin, K Alexoff, D Dewey, S AF Biegon, A Schiffer, WK Ding, Y Wu, H Pareto, D Lin, K Alexoff, D Dewey, S TI Non-invasive in vivo imaging of dynamic changes in NMDA receptor activation following surgical brain injury: A microPET study in rats SO REVIEWS IN THE NEUROSCIENCES LA English DT Meeting Abstract C1 Joseph Sagol Neurosci Ctr, Sheba, Israel. Brookhaven Natl Lab, Ctr Translat Neuroimaging, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FREUND & PETTMAN PUBLISHERS PI EAST YORKSHIRE PA ENHOLMES HALL, PATRINGTON, EAST YORKSHIRE HU12 OPR, ENGLAND SN 0334-1763 J9 REV NEUROSCIENCE JI Rev. Neurosci. PY 2005 VL 16 SU 1 BP S10 EP S10 PG 1 WC Neurosciences SC Neurosciences & Neurology GA 991HU UT WOS:000233804100041 ER PT J AU Deri, Y Katzav, A Chapman, J Biegon, A AF Deri, Y Katzav, A Chapman, J Biegon, A TI Sex differences and estrous cycle effects in experimental autoimmune encepahlomyelitis (EAE) in mice SO REVIEWS IN THE NEUROSCIENCES LA English DT Meeting Abstract C1 Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Brookhaven Natl Lab, Upton, NY 11973 USA. RI Katzav, Aviva/B-6702-2011; Chapman, Joab/E-4598-2010 NR 0 TC 0 Z9 0 U1 0 U2 1 PU FREUND & PETTMAN PUBLISHERS PI EAST YORKSHIRE PA ENHOLMES HALL, PATRINGTON, EAST YORKSHIRE HU12 OPR, ENGLAND SN 0334-1763 J9 REV NEUROSCIENCE JI Rev. Neurosci. PY 2005 VL 16 SU 1 BP S16 EP S16 PG 1 WC Neurosciences SC Neurosciences & Neurology GA 991HU UT WOS:000233804100067 ER PT J AU Grauer, E Spreekmeester, E Meaney, MJ Biegon, A AF Grauer, E Spreekmeester, E Meaney, MJ Biegon, A TI Long term effects of prolonged variable stress in rats treated with fluoxetine: Region dependent alterations in serotonin transporter density SO REVIEWS IN THE NEUROSCIENCES LA English DT Meeting Abstract C1 Israel Inst Biol Res, IL-70450 Ness Ziona, Israel. McGill Univ, Douglas Hosp, Res Ctr, Montreal, PQ, Canada. JSNC, Tel Hashomer, Israel. Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FREUND & PETTMAN PUBLISHERS PI EAST YORKSHIRE PA ENHOLMES HALL, PATRINGTON, EAST YORKSHIRE HU12 OPR, ENGLAND SN 0334-1763 J9 REV NEUROSCIENCE JI Rev. Neurosci. PY 2005 VL 16 SU 1 BP S26 EP S26 PG 1 WC Neurosciences SC Neurosciences & Neurology GA 991HU UT WOS:000233804100107 ER PT J AU Tsabari, R Schiffer, WK Biegon, A AF Tsabari, R Schiffer, WK Biegon, A TI Region-specific neuroinflammation and NMDA receptor changes after microdialysis probe implantation in rats. SO REVIEWS IN THE NEUROSCIENCES LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Funct Neuroimaging Ctr, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FREUND & PETTMAN PUBLISHERS PI EAST YORKSHIRE PA ENHOLMES HALL, PATRINGTON, EAST YORKSHIRE HU12 OPR, ENGLAND SN 0334-1763 J9 REV NEUROSCIENCE JI Rev. Neurosci. PY 2005 VL 16 SU 1 BP S65 EP S65 PG 1 WC Neurosciences SC Neurosciences & Neurology GA 991HU UT WOS:000233804100273 ER PT J AU Calado, VMA White, JM Muller, SJ AF Calado, VMA White, JM Muller, SJ TI Transient behavior of Boger fluids under extended shear flow in a cone-and-plate rheometer SO RHEOLOGICA ACTA LA English DT Article DE transient behavior; Boger fluids; extended shear flow; cone-and-plate rheometer; high molecular weight polymers; viscous solvents; binary solvents ID TAYLOR-COUETTE FLOW; ELASTIC INSTABILITY; POLYMER-SOLUTIONS; LINEAR-STABILITY; RHEOLOGY; TRANSITION; ENERGETICS AB Three different dilute solutions of high molecular weight polymers in viscous, binary solvents were used in experiments performed in a cone-and-plate rheometer. The solutions all fall into the class of fluids referred to as "Boger fluids" and were previously used in studies of viscoelastic Taylor-Couette instabilities. Under prolonged shearing in the cone-and-plate geometry, these fluids all exhibited a decrease of the first normal stress growth function N-1(+)(t) from an initial plateau value to a second, lower plateau value. This behavior has been previously observed, but is here reported for widely used polyisobutylene-based Boger fluids for the first time. As in earlier studies (Magda JJ, Lee C-S, Muller SJ, Larson RG (1993) Macromolecules 26:1696-1706; MacDonald M, Muller SJ (1997) J Rheol Acta 36:97-109), the time at which this decrease occurs (the decay time) is much longer than the polymer molecule's relaxation time. Here, we focus on three issues: 1) the time-temperature superposition of the first normal stress growth function N-1(+)(t), including the decay time and the value of the second plateau, 2) the sample recovery time required to reproduce the initial plateau value of N-1(+) and the decay time, and 3) the relationship between the time scales for this decay of normal stresses and the onset of viscous heating induced instabilities in the Taylor-Couette geometry. Our results suggest that shear-induced conformational changes, possibly coupled to viscous heating of the sample, may be responsible for the decrease in the first normal stress growth function during prolonged shearing. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Fed Rio de Janeiro, Escola Quim, Ctr Tecnol, BR-21990900 Rio De Janeiro, Brazil. Gen Elect Global Res, Niskayuna, NY 12309 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Muller, SJ (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. EM muller2@socrates.berkeley.edu NR 33 TC 4 Z9 4 U1 3 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0035-4511 J9 RHEOL ACTA JI Rheol. Acta PD JAN PY 2005 VL 44 IS 3 BP 250 EP 261 DI 10.1007/s00397-004-0404-5 PG 12 WC Mechanics SC Mechanics GA 887RN UT WOS:000226323300004 ER PT S AU Dale, VH Brown, S Calderon, MO Montoya, AS Martinez, RE AF Dale, VH Brown, S Calderon, MO Montoya, AS Martinez, RE BE Harmon, RS TI Projected land-use change for the Eastern Panama Canal Watershed and its potential impact SO RIO CHAGRES, PANAMA: A MULTIDISCIPLINARY PROFILE OF A TROPICAL WATERSHED SE Water Science and Technology Library LA English DT Proceedings Paper CT International Scientific Symposium on Rio Chagres Panama - A Multidisciplinary Profile of a Tropical Watershed CY FEB 24-26, 2003 CL Gamboa, PANAMA DE Panama; carbon baselines; carbon benefits; land-cover change; regional analyses; spatial projections; tropical deforestation ID FORESTS AB Human occupation of the Panama Canal Watershed has affected its land cover for the past century. A rule-based model was developed and applied to estimate changes in land use and subsequent carbon emissions over the next twenty years in the Eastern Panama Canal Watershed (EPCW). Projections show that the highest percent change in land use for the 'new-road' scenario compared to the 'business-as-usual' scenario is for urban areas, and the greatest cause of carbon emission is from deforestation. Thus, the most effective way to reduce carbon emissions to the atmosphere in the EPCW is by reducing deforestation. In addition to affecting carbon emissions, reducing deforestation would also protect the soil and water resources of the EPCW, which has important implications for the long-term sustainable operation of the Panama Canal. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Dale, VH (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 11 TC 1 Z9 1 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0921-092X BN 1-4020-3298-6 J9 WATER SCI TECHNOL LI PY 2005 VL 52 BP 337 EP 345 PG 9 WC Forestry; Soil Science; Water Resources SC Forestry; Agriculture; Water Resources GA BDE87 UT WOS:000233165300023 ER PT J AU Vassilevski, YV Dyadechko, VG Lipnikov, KN AF Vassilevski, YV Dyadechko, VG Lipnikov, KN TI Hessian-based anisotropic mesh adaptation in domains with discrete boundaries SO RUSSIAN JOURNAL OF NUMERICAL ANALYSIS AND MATHEMATICAL MODELLING LA English DT Article ID OPTIMIZATION AB Black-box methodology for generating anisotropic adaptive tetrahedral meshes in domains with discrete boundaries is described. A new high-order reconstruction method for triangular surface meshes is proposed. The performance of the method for a model convection-diffusion problem is demonstrated. C1 Russian Acad Sci, Inst Numer Math, Moscow 119991, Russia. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Vassilevski, YV (reprint author), Russian Acad Sci, Inst Numer Math, GSP 1, Moscow 119991, Russia. EM vasilevs@dodo.inm.ras.ru; vdyadechko@lanl.gov; lipnikov@lanl.gov RI Vassilevski, Yuri/A-6068-2016 NR 15 TC 3 Z9 5 U1 0 U2 0 PU VSP BV PI ZEIST PA PO BOX 346, 3700 AH ZEIST, NETHERLANDS SN 0927-6467 J9 RUSS J NUMER ANAL M JI Russ. J. Numer. Anal. Math. Model PY 2005 VL 20 IS 4 BP 391 EP 402 DI 10.1163/156939805775122307 PG 12 WC Engineering, Multidisciplinary; Mathematics, Applied SC Engineering; Mathematics GA 961IG UT WOS:000231654800007 ER PT J AU Glasser, AH Liseikin, VD Kitaeva, IA AF Glasser, AH Liseikin, VD Kitaeva, IA TI Specification of monitor metrics for generating vector field-aligned numerical grids SO RUSSIAN JOURNAL OF NUMERICAL ANALYSIS AND MATHEMATICAL MODELLING LA English DT Article AB An elliptic method based on comprehensive monitor metrics is developed for generating vector field-aligned grids. Some results of numerical experiments are demonstrated. C1 Los Alamos Natl Lab, Plasma Theory T15 Grp, Los Alamos, NM 87545 USA. Russian Acad Sci, Siberian Branch, Inst Computat Technol, Novosibirsk 630090, Russia. RP Glasser, AH (reprint author), Los Alamos Natl Lab, Plasma Theory T15 Grp, POB 1663,Mail Stop K717, Los Alamos, NM 87545 USA. NR 16 TC 4 Z9 5 U1 0 U2 0 PU VSP BV PI LEIDEN PA BRILL ACADEMIC PUBLISHERS, PO BOX 9000, 2300 PA LEIDEN, NETHERLANDS SN 0927-6467 J9 RUSS J NUMER ANAL M JI Russ. J. Numer. Anal. Math. Model PY 2005 VL 20 IS 5 BP 439 EP 461 DI 10.1163/156939805775186686 PG 23 WC Engineering, Multidisciplinary; Mathematics, Applied SC Engineering; Mathematics GA 993NR UT WOS:000233961300003 ER PT S AU Cooper, A AF Cooper, A BE Brebbia, CA Bucciarelli, T Garzia, F Guarascio, M TI A mathematically guided strategy for risk assessment and management SO Safety and Security Engineering SE WIT TRANSACTIONS ON THE BUILT ENVIRONMENT LA English DT Proceedings Paper CT 1st International Conference on Safety and Security Engineering CY JUN 13-15, 2005 CL Rome, ITALY SP Vatican City State, Senate Republic, Chamber Deputies, Presidency Council Minist Italy, CNR, Italy, Presidency Council Minist, Dept Civil Protect, Natl Inst Nucl Phys, Natl Inst Geophys & Volcanol, Minist Innovat & Technologies, Minist Commun, Univ & Res, Minist Educ, Minist Environm, Minist Hlth, Minist Infrastruct & Transport, Minist Product Activities, Natl Council Engineers, FASTIGI Consortium, WIT Transact Built Environm, Wessex Inst Technol, Univ Rome La Sapienza, Fac Engn, Natl Fire Dept DE risk analysis; assessment and management; safety engineering; latent effects; hybrid analysis AB Strategies for risk assessment and management of high consequence operations are often based on factors such as physical analysis, analysis of software and other logical processing, and analysis of statistically determined human actions. Conventional analysis methods work well for processing objective information. However, in practical situations, much or most of the data available are subjective. Also, there are potential resultant pitfalls where conventional analysis might be unrealistic, such as improperly using event tree and fault tree failure descriptions where failures or events are soft (partial) rather than crisp (binary), neglecting or misinterpreting dependence (positive, negative, correlation), and aggregating nonlinear contributions linearly. There are also personnel issues that transcend basic human factors statistics. For example, sustained productivity and safety in critical operations can depend on the morale of involved personnel. In addition, motivation is significantly influenced by "latent effects," which are pre-occurring influences. This paper addresses these challenges and proposes techniques for subjective risk analysis, latent effects risk analysis and a hybrid analysis that also includes objective risk analysis. The goal is an improved strategy for risk management. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Cooper, A (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU WIT PRESS PI SOUTHAMPTON PA ASHURST LODGE, SOUTHAMPTON SO40 7AA, ASHURST, ENGLAND SN 1746-4498 BN 1-84564-019-5 J9 WIT TRANS BUILT ENV PY 2005 VL 82 BP 105 EP 114 PG 10 WC Engineering, Multidisciplinary SC Engineering GA BCZ14 UT WOS:000232028700011 ER PT B AU Christensen, RM AF Christensen, RM BE Thomsen, OT Bozhevolnaya, E Lyckegaard, A TI A two-property yield, failure (fracture) criterion for isotropic matrix materials SO Sandwich Structures7: Advancing with Sandwich Structures and Materials LA English DT Proceedings Paper CT 7th International Conference on Sandwich Structures CY AUG 29-31, 2005 CL Aalborg Univ, Aalborg, DENMARK SP Aalborg Univ, Inst Mech Engn HO Aalborg Univ DE yield; fracture; failure criterion AB A yield/failure criterion is coordinated with a separate fracture criterion to provide a comprehensive three dimensional description of failure for isotropic materials. Two properties provide the entire calibration for the two criteria. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Christensen, RM (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 1-4020-3444-X PY 2005 BP 117 EP 120 DI 10.1007/1-4020-3848-8_11 PG 4 WC Engineering, Mechanical; Materials Science, Composites SC Engineering; Materials Science GA BDF39 UT WOS:000233234700011 ER EF