FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Oda, MN Bielicki, JK Ho, TT Berger, T Rubin, EM Forte, TM AF Oda, MN Bielicki, JK Ho, TT Berger, T Rubin, EM Forte, TM TI Paraoxonase 1 overexpression in mice and its effect on high-density lipoproteins SO BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS LA English DT Article DE paraoxonase; transgenic mice; lipid peroxidation; lecithin : cholesterol acyltransferase; highdensity lipoproteins ID CHOLESTEROL ACYLTRANSFERASE ACTIVITY; INHIBIT PLASMA LECITHIN; SERUM PARAOXONASE; LIPID HYDROPEROXIDES; OXIDIZED LDL; 3 STEPS; APOLIPOPROTEIN; PHOSPHOLIPIDS; ARYLESTERASE; PROTECTION AB Paraoxonase (PON1) is a high-density lipoprotein (HDL)-associated enzyme believed to protect against the early events of atherogenesis by its ability to hydrolyze oxidized phospholipids. A transgenic mouse overexpressing PON1 (mPON1) was developed to address the question of whether overexpression of PON1 is important in protecting HDL function during oxidative stress. Transgenic mice were obtained that have up to a 5-fold increase in mPON1 activity measured as arylesterase activity [52.7 +/- 17.3 U/ml versus 251.7 +/- 25.1 U/ml for wild-type (WT) and mPON1 high expressers, respectively]; this increase in mPON1 activity was reflected by a 5.3-fold increase in relative mass of the enzyme. Excess mPON1 was associated solely with HDL but did not alter HDL composition, size, or charge. Lecithin:cholesterol acyltransferase (LCAT) on HDL is a sensitive indicator of oxidative stress; exposure of plasmas from both WT and mPON1 overexpresser mice to 0.4 mM copper ions for 2 h showed a 30-40% protection of LCAT activity in mPON1 overexpressers compared to WT. Excess mPON1 also inhibited lipid hydroperoxide formation on HDL. These data strongly suggest that overexpression of mPON1 protects HDL integrity and function. (C) 2002 Elsevier Science (USA). C1 Lawrence Berkeley Natl Lab, Life Sci Div MS 1 220, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Anim Sci, Davis, CA 95616 USA. RP Forte, TM (reprint author), Lawrence Berkeley Natl Lab, Life Sci Div MS 1 220, 1 Cylotron Rd, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [HL07279, HL18574, HL59483] NR 30 TC 76 Z9 90 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0006-291X J9 BIOCHEM BIOPH RES CO JI Biochem. Biophys. Res. Commun. PD JAN 25 PY 2002 VL 290 IS 3 BP 921 EP 927 DI 10.1006/bbrc.2001.6295 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 517LF UT WOS:000173611500007 PM 11798161 ER PT J AU Kim, Y Kim, S Earnest, TN Hol, WGJ AF Kim, Y Kim, S Earnest, TN Hol, WGJ TI Precursor structure of cephalosporin acylase - Insights into autoproteolytic activation in a new N-terminal hydrolase family SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID 7-AMINOCEPHALOSPORANIC ACID ACYLASE; ELECTRON-DENSITY; STRAIN; MECHANISM; PROTEINS; ASPARTYLGLUCOSAMINIDASE; CLASSIFICATION; PROTEASOME; MOLSCRIPT; PROGRAM AB Autocatalytic proteolytic cleavage is a frequently observed post-translational modification in proteins. Cephalosporin acylase (CA) is a recently identified member of the N-terminal hydrolase family that is activated from an inactive precursor by autoproteolytic processing, generating a new N-terminal residue, which is either a Ser or a Thr. The N-terminal Ser or Thr becomes a nucleophilic catalytic center for intramolecular and intermolecular amide cleavages. The gene structure of the open reading frame of CAs generally consists of a signal peptide followed by the alpha-subunit, a spacer sequence, and the beta-sub-unit, which are all translated into a single polypeptide chain, the CA precursor. The precursor is post-translationally modified into an active heterodimeric enzyme with alpha- and beta-subunits, first by intramolecular cleavage and second by intermolecular cleavage. We solved the first CA precursor structure (code 1KEH) from a class I CA from Pseudomonas diminuta at a 2.5-Angstrom resolution that provides insight into the mechanism of intramolecular cleavage. A conserved water molecule, stabilized by four hydrogen bonds in unusual pseudotetrahedral geometry, plays a key role to assist the OG atom of Ser(1beta) to generate a strong nucleophile. In addition, the site of the secondary intermolecular cleavage of CA is proposed to be the carbonyl carbon of Gly(158alpha) (Kim, S., and Kim, Y., (2001) J. BioL Chem., 276,48376-48381), which is different from the situation in two other class I CAs. C1 Yeungnam Univ, Sch Chem Engn, Kyongsan 712749, South Korea. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley Ctr Struct Biol, Berkeley, CA 94720 USA. Univ Washington, Dept Biochem, Biomol struct Ctr, Seattle, WA 98195 USA. Univ Washington, Howard Hughes Med Inst, Seattle, WA 98195 USA. RP Kim, Y (reprint author), Yeungnam Univ, Sch Chem Engn, Dae Dong, Kyongsan 712749, South Korea. RI Kim, Youngsoo/D-6046-2012 NR 32 TC 47 Z9 51 U1 0 U2 3 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD JAN 25 PY 2002 VL 277 IS 4 BP 2823 EP 2829 DI 10.1074/jbc.M108888200 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 514CY UT WOS:000173421500060 PM 11706000 ER PT J AU Mihlbachler, K Jupke, A Seidel-Morgenstern, A Schmidt-Traub, H Guiochon, G AF Mihlbachler, K Jupke, A Seidel-Morgenstern, A Schmidt-Traub, H Guiochon, G TI Effect of the homogeneity of the column set on the performance of a simulated moving bed unit II. Experimental study SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT International Symposium on Preparative and Process Chromatography CY MAY 13-16, 2001 CL WASHINGTON, D.C. DE simulated moving bed chromatography; porosity; enantiomer separation; adsorption isotherms; mathematical modeling; Troger's base ID ADSORPTION SEPARATION PROCESSES; LIQUID-CHROMATOGRAPHY; POLARIMETRIC DETECTION; ENANTIOMERS; ENANTIOSEPARATION; COUNTERCURRENT; OPTIMIZATION; EQUILIBRIUM; PROFILES; ISOTHERM AB Previous studies of the simulated moving bed (SMB) process assume identical characteristics of all. the columns incorporated in a given unit. Due to the practical impossibility to manufacture identical columns, numerical applications of the theory to modeling and optimization use for each of the needed column parameter the average value for the entire column set. In this study, the effects of these simplifications on the actual productivity of the SMB process are evaluated by making exact calculations, i.e., by taking the differences in the porosity values into account. We apply a revised set of separation conditions previously introduced and derived from the eqiuilibrium theory. Earlier theoretical results are compared to experimental results obtained in the study of the enantiomeric separation of Troger's base on Chiralpak AD. Due to the nonLangmuirian character of the adsorption isotherms of these two compounds on the packing material used, the separation area cannot be determined analytically. As an alternative, a reliable numerical algorithm was used to scan a wider region and to define the separation area. The form of this area depends on the applied porosity values. A UV detector and a laser polarimeter located at one node of the SMB monitor on-line the internal concentration profiles. Excellent agreement between the calculated and the experimentally determined concentration profiles was obtained under nonlinear conditions. The influence of column-to-column variations on the performance of the SMB process was found to be more significant under nonlinear than under linear conditions. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN USA. Univ Magdeburg, Dept Chem Engn, D-39106 Magdeburg, Germany. Univ Dortmund, Dept Chem Engn, Dortmund, Germany. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, 552 Buehler Hall, Knoxville, TN 37996 USA. EM guiochon@utk.edu OI Seidel-Morgenstern, Andreas/0000-0001-8595-7810 NR 46 TC 24 Z9 24 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JAN 25 PY 2002 VL 944 IS 1-2 BP 3 EP 22 DI 10.1016/S0021-9673(01)01396-6 PG 20 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 512LT UT WOS:000173326400002 PM 11831762 ER PT J AU McCord, TB Teeter, G Hansen, GB Sieger, MT Orlando, TM AF McCord, TB Teeter, G Hansen, GB Sieger, MT Orlando, TM TI Brines exposed to Europa surface conditions SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article DE Europa; Galilean satellites; surface materials; material properties; salt minerals; hydrated minerals ID ELECTRON-STIMULATED DISSOCIATION; STRIKE-SLIP FAULTS; AMORPHOUS D2O ICE; GEOLOGICAL EVIDENCE; SUBSURFACE OCEAN; WATER ICE; SODIUM; ATMOSPHERE; SATELLITES; DESORPTION AB [1] Evidence for an ocean beneath the icy crust of Europa includes reflectance spectra of disrupted surface regions indicating hydrated materials such as salts. We simulated exposure of salty brine on the cold surface of Europa by flash-freezing sulfate and carbonate solutions. This produces materials that have near-infrared reflectance spectra distinct from those for crystalline minerals and more similar to those for Europa's non-ice regions. These new spectroscopic data, along with geophysical evidence, geochemical models, and meteorite studies, strongly suggest that the non-ice materials in the disrupted regions on Europa's surface contain large amounts of disordered and heavily hydrated MgSO(4) and perhaps Na(2)SO(4) that are endogenic in origin. C1 Univ Hawaii, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA USA. RP McCord, TB (reprint author), Univ Hawaii, Hawaii Inst Geophys & Planetol, 2525 Correa Rd, Honolulu, HI 96822 USA. EM tom@higp.hawaii.edu; thomas.orlando@chemistry.gatech.edu RI Sieger, Matthew/B-4261-2011 OI Sieger, Matthew/0000-0001-7387-3660 NR 39 TC 23 Z9 23 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD JAN 25 PY 2002 VL 107 IS E1 AR 5004 DI 10.1029/2000JE001453 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 554FZ UT WOS:000175725800004 ER PT J AU Holm, DD AF Holm, DD TI Variational principles for Lagrangian-averaged fluid dynamics SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article ID CAMASSA-HOLM EQUATIONS; MEAN-FLOW; GEOMETRY; MODELS AB The Lagrangian average (LA) of the ideal fluid equations preserves their fundamental transport structure. This transport structure is responsible for the Kelvin circulation theorem of the LA flow and, hence, for its potential vorticity convection and helicity conservation. We show that Lagrangian averaging also preserves the Euler-Poincare variational framework that implies the exact ideal fluid equations in the Eulerian representation. This is expressed in the Lagrangian-averaged Euler-Poincare (LAEP) theorem proved here. We illustrate the LAEP theorem by applying it to incompressible ideal fluids to derive the Lagrangian-averaged Euler equations and thereby recover the generalized Lagrangian mean motion equation. Finally, we discuss recent progress in applications of these equations as the basis for new LA closure models of fluid turbulence. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Holm, DD (reprint author), Los Alamos Natl Lab, Div Theoret, MS B284, Los Alamos, NM 87545 USA. OI Holm, Darryl D/0000-0001-6362-9912 NR 24 TC 10 Z9 10 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD JAN 25 PY 2002 VL 35 IS 3 BP 679 EP 688 AR PII S0305-4470(02)23713-0 DI 10.1088/0305-4470/35/3/313 PG 10 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 523PV UT WOS:000173964900015 ER PT J AU Mihaila, B Mihaila, I AF Mihaila, B Mihaila, I TI Numerical approximations using Chebyshev polynomial expansions: El-gendi's method revisited SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article ID QUANTUM-FIELD THEORY; LARGE-N EXPANSION; TIME EVOLUTION; SCALAR FIELD; DYNAMICS; THERMALIZATION; RELAXATION; SYSTEM AB We present numerical solutions for differential equations by expanding the unknown function in terms of Chebyshev polynomials and solving a system of linear equations directly for the values of the function at the extrema (or zeros) of the Chebyshev polynomial of order N (El-gendi's method). The solutions are exact at these points, apart from round-off computer errors and the convergence of other numerical methods used in solving the linear system of equations. Applications to initial value problems in time-dependent quantum field theory, and second-order boundary value problems in fluid dynamics are presented. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Coastal Carolina Univ, Dept Math & Stat, Conway, SC 29528 USA. RP Mihaila, B (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RI Mihaila, Bogdan/D-8795-2013 OI Mihaila, Bogdan/0000-0002-1489-8814 NR 54 TC 23 Z9 23 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD JAN 25 PY 2002 VL 35 IS 3 BP 731 EP 746 AR PII S0305-4470(02)27127-9 DI 10.1088/0305-4470/35/3/317 PG 16 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 523PV UT WOS:000173964900019 ER PT J AU Turner, L Pratt, J AF Turner, L Pratt, J TI Eddy-damped quasinormal Markovian closure: a closure for magnetohydrodynamic turbulence? SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article ID STATISTICAL-MECHANICS; RANDOM-PHASE; DYNAMO AB A set of nonlinear differential equations are developed that are analogous to the spectral evolution equations of incompressible magnetohydrodynamics (MHD). Because these equations possess little detail of MHD, apart from salient symmetry properties, they provide a toy model in which aspects of turbulent MHD can be understood readily. In the context of this model, the eddy-damped quasinormal Markovian (EDQNM) closure often used in Navier-Stokes turbulence is demonstrated to provide physically realizable spectra for magnetohydrodynamic turbulence, if the eddy-damping functions are chosen to satisfy certain symmetry properties. The requirements of physical realizability are more demanding in MHD than in fluid turbulence. In the absence of mean fields, this model demonstrates that the components of not only the turbulent kinetic energy spectrum, but also the magnetic energy spectra, never become negative. Another condition for realizability possessed by this model is that the components of the turbulent cross-helicity spectrum always satisfy a Schwarz inequality with respect to the corresponding components of the kinetic and magnetic energy spectra. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Turner, L (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Pratt, Jane/A-2462-2013 OI Pratt, Jane/0000-0003-2707-3616 NR 23 TC 1 Z9 1 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD JAN 25 PY 2002 VL 35 IS 3 BP 781 EP 793 AR PII S0305-4470(02)26973-5 DI 10.1088/0305-4470/35/3/320 PG 13 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 523PV UT WOS:000173964900022 ER PT J AU Nielsen, IMB Zou, SLL Bowman, JM Janssen, CL AF Nielsen, IMB Zou, SLL Bowman, JM Janssen, CL TI Characterization of the sulfur fluoride radical in the ground electronic state SO CHEMICAL PHYSICS LETTERS LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; MICROWAVE-SPECTRUM; DIPOLE-MOMENTS; SF; THERMOCHEMISTRY; ATOMS; IONS; DISSOCIATION; N=1-6 AB The (2)Pi ground electronic state of the sulfur fluoride radical has been characterized by high-level ab initio methods, employing the CCSD(T) method with large, augmented correlation-consistent basis sets including aug-cc-pVTZ, aug-cc-pwCVTZ, and aug-cc-pVQZ. Anharmonic vibrational wave functions have been computed, and previously unavailable transition moments and infrared intensities have been obtained along with dipole moments for the lower vibrational states. A refined theoretical prediction is made for the dipole moment it,. and the performance of the CCSD(T) method with the above basis sets is investigated for several other molecular constants for which experimental values are available. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Emory Univ, Dept Chem, Atlanta, GA 30322 USA. Emory Univ, Cherry L Emerson Ctr Sci Computat, Atlanta, GA 30322 USA. RP Nielsen, IMB (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. NR 23 TC 8 Z9 8 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 24 PY 2002 VL 352 IS 1-2 BP 26 EP 32 DI 10.1016/S0009-2614(01)01382-3 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 518YL UT WOS:000173695800005 ER PT J AU Harvey, SD Vucelick, ME Lee, RN Wright, BW AF Harvey, SD Vucelick, ME Lee, RN Wright, BW TI Blind field test evaluation of Raman spectroscopy as a forensic tool SO FORENSIC SCIENCE INTERNATIONAL LA English DT Article DE portable Raman analysis; reliability of Raman identification; blind field test; emergency response; identification of hazardous materials counterterrorism ID MICROPROBE SPECTROSCOPY; IDENTIFICATION; NARCOTICS AB Analytical instrumentation for Raman spectroscopy has advanced rapidly in recent years to the point where commercial field-portable instruments are available. Raman analysis with portable instrumentation is a new capability that can provide emergency response teams with on-site evaluation of hazardous materials. Before Raman analysis is accepted and implemented in the field, realistic studies applied to unknown samples need to be performed to define the reliability of this technique. Studies described herein provide a rigorous blind field test that utilizes two instruments and two operators to analyze a matrix that consists of 58 unknown samples. Samples were searched against a custom hazardous materials reference library (Hazardous Material Response Unit (HMRU) Spectral Library Database). Experimental design included a number of intentionally difficult situations including binary solvent mixtures and a variety of compounds that yield medium-quality spectra that were not contained in the HMRU library. Results showed that over 97% of the samples were correctly identified with no occurrences of false positive identifications (Compounds that were not in the library were never identified as library constituents). Statistical analysis indicated equivalent performance for both the operators and instruments. These results indicate a high level of performance that should extrapolate to actual field situations. Implementation of Raman techniques to emergency field situations should proceed with a corresponding level of confidence. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Assoc Western Univ, Grad Sch Program, Richland, WA 99352 USA. RP Harvey, SD (reprint author), Pacific NW Natl Lab, Battelle Blvd,POB 999, Richland, WA 99352 USA. NR 15 TC 40 Z9 40 U1 1 U2 9 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0379-0738 J9 FORENSIC SCI INT JI Forensic Sci.Int. PD JAN 24 PY 2002 VL 125 IS 1 BP 12 EP 21 AR PII S0379-0738(01)00615-6 DI 10.1016/S0379-0738(01)00615-6 PG 10 WC Medicine, Legal SC Legal Medicine GA 534YX UT WOS:000174618300003 PM 11852198 ER PT J AU Rack, JJ McCleskey, TM Birnbaum, ER AF Rack, JJ McCleskey, TM Birnbaum, ER TI Perturbing the sequestered water-pool in microemulsions: The role of the probe in affecting reverse micelle equilibria SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID CHARGE-TRANSFER; EXCITED-STATE; Y-ZEOLITE; PHOTOPHYSICAL PROPERTIES; SOLVATION DYNAMICS; INVERTED MICELLES; SOLUBILIZED WATER; IR INVESTIGATIONS; METAL-COMPLEXES; N-HEPTANE AB The incorporation Of [Ru(bpy)(3)](2+) within microemulsions formed from anionic (AOT, sodium bis(2-ethylhexyl)sulfosuccinate) and cationic surfactants (CTAB, cetyltrimethylammoniurn bromide) has been investigated by steady-state and time-resolved emission spectroscopy as a function of water content (3 less than or equal to w(0) less than or equal to 15; w(0) = [H2O]/[surfactant]). For anionic surfactants, [Ru(bpy)(3)](2+) is localized at the surfactant interface, and its emission is characterized by monoexponential kinetics at all w(0) values. For cationic surfactants, the emission decay is strictly monoexponential at large w(0) values. At small w(0) values (< 10), the decay is biexponential, and time-resolved emission spectra reveal two discrete emission maxima. These results are interpreted as surfactant-probe interactions driving the formation of at least two different-sized nanodroplets. C1 Los Alamos Natl Labs, Div Chem, Los Alamos, NM 87545 USA. RP McCleskey, TM (reprint author), Los Alamos Natl Labs, Div Chem, MS J514, Los Alamos, NM 87545 USA. RI McCleskey, Thomas/J-4772-2012; OI Mccleskey, Thomas/0000-0003-3750-3245 NR 38 TC 21 Z9 21 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 24 PY 2002 VL 106 IS 3 BP 632 EP 636 DI 10.1021/jp012472l PG 5 WC Chemistry, Physical SC Chemistry GA 513BE UT WOS:000173357400017 ER PT J AU Kretzschmar, I Friend, CM Sigman, ME AF Kretzschmar, I Friend, CM Sigman, ME TI Effect of coadsorbed species and temperature on competitive reaction channels for nascent radicals: c-C3H7CH2SH on Mo(110)-(6x1)-O SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID OXYGEN-PRECOVERED MO(110); LASER FLASH-PHOTOLYSIS; C-O; REACTION-MECHANISMS; METHANOL REACTION; REACTION-KINETICS; SURFACE-REACTION; COVERED MO(110); METAL-SURFACES; BOND SCISSION AB The reaction of cyclopropylmethanethiol on oxygen-modified Mo(I 10) is studied as a means of probing for radical species and their residence times on surfaces. A thiolate species and a surface hydroxyl group, OH,, form upon adsorption of cyclopropylmethanethiol on O-covered Mo(l 10). Near 200 K, homolytic cleavage of the thiolate C-S bond occurs, yielding the methylcyclopropyl radical. The radical abstracts hydrogen from OHa and desorbs without rearrangement as methylcyclopropane. Between 300 and 350 K, trapping of the ring-closed radical by surface oxygen via C-O bond formation competes efficiently because of an increasing number of free oxygen sites, resulting in a surface covered with methylcyclopropoxide species. Reactions of the cyclic alkoxide are similar to those observed for the 0 analogue hydroxymethylcyclopropane; it undergoes C-O bond scission, rearranges to the butenyl radical, and forms linear alkoxide and alkyl species between 350 and 430 K. However, the sulfur deposited by C-S bond cleavage (similar to0.2 monolayer) leads to complete suppression of nonselective decomposition. Assuming that the rate constant for rearrangement on the surface is similar to that in solution, limits are estimated for the rate constants for hydrogenation and trapping: k(hydrogenation)(200 K) > 2.5 x 10(6) s(-1), k(hydrogenation)(350 K) < 4.73 x 10(8) s(-1), k(trap)(350 K) > 4.73 x 10(8) s(-1), and k(trap)(430 K) < 30.7 x 10(8) s(-1). Comparison with reaction of cyclopropylmethanethiol on clean Mo(I 10) reveals that modification of the surface with oxygen reduces the amount of desulfurization by 35% to 40%. Further, it opens a new reaction channel, i.e., C-O bond formation, and-completely suppresses the 25% of complete decomposition observed on clean Mo(110). C1 Harvard Univ, Dept Chem, Cambridge, MA 02138 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Friend, CM (reprint author), Harvard Univ, Dept Chem, Cambridge, MA 02138 USA. NR 52 TC 8 Z9 8 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 24 PY 2002 VL 106 IS 3 BP 663 EP 672 DI 10.1021/jp013238y PG 10 WC Chemistry, Physical SC Chemistry GA 513BE UT WOS:000173357400021 ER PT J AU Zheng, F Zhan, CG Ornstein, RL AF Zheng, F Zhan, CG Ornstein, RL TI Theoretical determination of two structural forms of the active site in cadmium-containing phosphotriesterases SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID BINUCLEAR METAL CENTER; REACTION FIELD-THEORY; BACTERIAL PHOSPHOTRIESTERASE; 3-DIMENSIONAL STRUCTURE; PSEUDOMONAS-DIMINUTA; HISTIDINE; INACTIVATION; MECHANISM; BINDING; ESTERS AB Two structural forms of the active site in Cd2+-containing phosphotriesterases (PTE), i.e., Cd2+/Cd2+ -PTE and Zn2+/Cd2+-PTE, were determined by performing ab initio and density functional theory calculations on active site models. The calculated results indicate that the second bridging ligand in the active site of the recently reported high-resolution X-ray crystal structures of Cd2+/Cd2+ -PTE and Zn2+/Cd2+ -PTE should be a hydroxide ion, rather than a water molecule. The protonated active site structures of the Cd2+-containing enzymes are all significantly different from that of Zn2+/Zn2+ -PTE. In Cd2+/Cd2+-PTE and Zn2+/Cd2+- PTE, the second bridging ligand always simultaneously coordinates to the two metal ions, whether it is a hydroxide ion or a water molecule. The pK(a) values calculated for the second bridging ligand are in good agreement with the observed kinetic pK(a) values for both the Cd2+- and Zn2+-substituted enzymes. The calculated results strongly support the conclusion that the observed kinetic pK(a) is actually the pK(a) of the second bridging ligand, and strongly support the previously postulated catalytic mechanism of PTE involving a bridging hydroxide that attacks the phosphorus center of the substrate. C1 Columbia Univ, Dept Med, Coll Phys & Surg, New York, NY 10032 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Zhan, CG (reprint author), Columbia Univ, Dept Med, Coll Phys & Surg, New York, NY 10032 USA. NR 36 TC 46 Z9 47 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 24 PY 2002 VL 106 IS 3 BP 717 EP 722 DI 10.1021/jp013064k PG 6 WC Chemistry, Physical SC Chemistry GA 513BE UT WOS:000173357400027 ER PT J AU Lang, KM Madhavan, V Hoffman, JE Hudson, EW Eisaki, H Uchida, S Davis, JC AF Lang, KM Madhavan, V Hoffman, JE Hudson, EW Eisaki, H Uchida, S Davis, JC TI Imaging the granular structure of high-T-c superconductivity in underdoped Bi2Sr2CaCu2O8+delta SO NATURE LA English DT Article ID PHASE-SEPARATION; STATES; EXCITATIONS; PSEUDOGAP; DENSITY; OXIDES; MODEL AB Granular superconductivity occurs when microscopic superconducting grains are separated by non-superconducting regions; Josephson tunnelling between the grains establishes the macroscopic superconducting state(1). Although crystals of the copper oxide high-transition-temperature (high-T-c) superconductors are not granular in a structural sense, theory suggests that at low levels of hole doping the holes can become concentrated at certain locations resulting in hole-rich superconducting domains(2-5). Granular superconductivity arising from tunnelling between such domains would represent a new view of the under-doped copper oxide superconductors. Here we report scanning tunnelling microscope studies of underdoped Bi2Sr2CaCu2O8+delta that reveal an apparent segregation of the electronic structure into superconducting domains that are similar to3nm in size (and local energy gap <50 meV), located in an electronically distinct background. We used scattering resonances at Ni impurity atoms(6) as 'markers' for local superconductivity(7-9); no Ni resonances were detected in any region where the local energy gap &UDelta;>50+/-2.5 meV. These observations suggest that underdoped Bi2Sr2CaCu2O8+delta is a mixture of two different short-range electronic orders with the long-range characteristics of a granular superconductor. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Tokyo, Dept Supercond, Bunkyo Ku, Tokyo 1138656, Japan. Stanford Univ, Dept Appl Phys, Stanford, CA 94205 USA. RP Davis, JC (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Hudson, Eric/C-2746-2008; Hoffman, Jennifer/H-4334-2011 OI Hudson, Eric/0000-0001-7064-0351; Hoffman, Jennifer/0000-0003-2752-5379 NR 32 TC 594 Z9 594 U1 5 U2 56 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 24 PY 2002 VL 415 IS 6870 BP 412 EP 416 DI 10.1038/415412a PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 514HR UT WOS:000173433600045 PM 11807550 ER PT J AU Link, JM Reyes, M Yager, PM Anjos, JC Bediaga, I Gobel, C Magnin, J Massafferri, A de Miranda, JM Pepe, IM dos Reis, AC Carrillo, S Casimiro, E Cuautle, E Sanchez-Hernandez, A Uribe, C Vazquez, F Agostino, L Cinquini, L Cumalat, JP O'Reilly, B Ramirez, JE Segoni, I Butler, JN Cheung, HWK Chiodini, G Gaines, I Garbincius, PH Garren, LA Gottschalk, E Kasper, PH Kreymer, AE Kutschke, R Bianco, S Kryemadhi, A Zallo, A Cawlfield, C Kim, DY Rahimi, A Wiss, J Gardner, R Kryemadhi, A Chung, YS Kang, JS Ko, BR Kwak, JW Lee, KB Park, H Alimonti, G Barberis, S Boschini, M D'Angelo, P DiCorato, M Dini, P Edera, L Erba, S Giammarchi, M Inzani, P Leveraro, F Malvezzi, S Menasce, D Mezzadri, M Milazzo, L Moroni, L Pedrini, D Pontoglio, C Prelz, F Rovere, M Sala, S Davenport, TF Arena, V Boca, G Bonomi, G Gianini, G Liguori, G Merlo, MM Pantea, D Ratti, SP Riccardi, C Vitulo, P Hernandez, H Lopez, AM Mendez, H Mendez, L Montiel, E Olaya, D Paris, A Quinones, J Rivera, C Xiong, W Zhang, Y Wilson, JR Cho, K Handler, T Mitchell, R Engh, D Hosack, M Johns, WE Nehring, M Sheldon, PD Stenson, K Vaandering, EW Webster, M Sheaff, M AF Link, JM Reyes, M Yager, PM Anjos, JC Bediaga, I Gobel, C Magnin, J Massafferri, A de Miranda, JM Pepe, IM dos Reis, AC Carrillo, S Casimiro, E Cuautle, E Sanchez-Hernandez, A Uribe, C Vazquez, F Agostino, L Cinquini, L Cumalat, JP O'Reilly, B Ramirez, JE Segoni, I Butler, JN Cheung, HWK Chiodini, G Gaines, I Garbincius, PH Garren, LA Gottschalk, E Kasper, PH Kreymer, AE Kutschke, R Bianco, S Kryemadhi, A Zallo, A Cawlfield, C Kim, DY Rahimi, A Wiss, J Gardner, R Kryemadhi, A Chung, YS Kang, JS Ko, BR Kwak, JW Lee, KB Park, H Alimonti, G Barberis, S Boschini, M D'Angelo, P DiCorato, M Dini, P Edera, L Erba, S Giammarchi, M Inzani, P Leveraro, F Malvezzi, S Menasce, D Mezzadri, M Milazzo, L Moroni, L Pedrini, D Pontoglio, C Prelz, F Rovere, M Sala, S Davenport, TF Arena, V Boca, G Bonomi, G Gianini, G Liguori, G Merlo, MM Pantea, D Ratti, SP Riccardi, C Vitulo, P Hernandez, H Lopez, AM Mendez, H Mendez, L Montiel, E Olaya, D Paris, A Quinones, J Rivera, C Xiong, W Zhang, Y Wilson, JR Cho, K Handler, T Mitchell, R Engh, D Hosack, M Johns, WE Nehring, M Sheldon, PD Stenson, K Vaandering, EW Webster, M Sheaff, M TI Measurement of natural widths of Sigma(0)(c) and Sigma(++)(c) baryons SO PHYSICS LETTERS B LA English DT Article ID CHARMED BARYONS; QUARK-MODEL; DECAYS AB In this letter we present a measurement of the natural widths of Sigma(c)(0) and Sigma(c)(++). Using data from the FOCUS experiment, we find Gamma( Sigma(c)(0)) = 1.55(-0.37)(+0.41) +/- 0.38 MeV/c(2) and Gamma(Sigma(c)(++)) = 2.05(-0.38)(+0.41) +/- 0.38 MeV/c(2). The first errors are statistical, the second systematic. These results are obtained with a sample of 913 Sigma(c)(0) --> Lambda(c)(+)pi(-) decays and 1110 Sigma(c)(++) --> Lambda(c)(++)pi(+) decays. These results are compared with recent theoretical predictions. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Calif Davis, Davis, CA 95616 USA. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, RJ, Brazil. CINVESTAV, Mexico City 07000, DF, Mexico. Univ Colorado, Boulder, CO 80309 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Illinois, Urbana, IL 61801 USA. Indiana Univ, Bloomington, IN 47405 USA. Korea Univ, Seoul 136701, South Korea. Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Milan, Milan, Italy. Univ N Carolina, Asheville, NC 28804 USA. Dipartimento Fis Teorica & Nucl, Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Puerto Rico, Mayaguez, PR 00681 USA. Univ S Carolina, Columbia, SC 29208 USA. Univ Tennessee, Knoxville, TN 37996 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Link, JM (reprint author), Univ Calif Davis, Davis, CA 95616 USA. RI Bonomi, Germano/G-4236-2010; Kwak, Jungwon/K-8338-2012; Link, Jonathan/L-2560-2013; Gobel Burlamaqui de Mello, Carla /H-4721-2016 OI Bonomi, Germano/0000-0003-1618-9648; Link, Jonathan/0000-0002-1514-0650; Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X NR 15 TC 11 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JAN 24 PY 2002 VL 525 IS 3-4 BP 205 EP 210 DI 10.1016/S0370-2693(01)01444-7 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 513RQ UT WOS:000173393000001 ER PT J AU Abazov, VM Abbott, B Abdesselam, A Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Ahmed, SN Alexeev, GD Alton, A Alves, GA Amos, N Anderson, EW Arnoud, Y Avila, C Baarmand, MM Babintsev, VV Babukhadia, L Bacon, TC Baden, A Baldin, BB Balm, PW Banerjee, S Barberis, E Baringer, P Barreto, J Bartlett, JF Bassler, U Bauer, A Bean, A Beaudette, F Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Beuselinck, R Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blekman, F Blessing, S Boehnlein, A Bojko, NI Borcherding, F Bos, K Bose, T Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Coney, L Connolly, B Cooper, WE Coppage, D Crepe-Renaudin, S Cummings, MAC Cutts, D Davis, GA Davis, K De, K de Jong, SJ Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Doulas, S Ducros, Y Dudko, LV Duensing, S Duflot, L Dugad, SR Duperrin, A Dyshkant, A Edmunds, D Ellison, J Eltzroth, JT Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Filthaut, F Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Fox, H Frame, KC Fu, S Fuess, S Gallas, E Galyaev, AN Gao, M Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Greenwood, ZD Grinstein, S Groer, L Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinmiller, JM Heinson, AP Heintz, U Hildreth, MD Hirosky, R Hobbs, JD Hoeneisen, B Huang, Y Iashvili, I Illingworth, R Ito, AS Jaffre, M Jain, S Jesik, R Johns, K Johnson, M Jonckheere, A Jostlein, H Juste, A Kahl, W Kahn, S Kajfasz, E Kalinin, AM Karmanov, D Karmgard, D Kehoe, R Khanov, A Kharchilava, A Kim, SK Klima, B Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kothari, B Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krivkova, P Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kupco, A Kuznetsov, VE Landsberg, G Lee, WM Leflat, A Leggett, C Lehner, F Leonidopoulos, C Li, J Li, QZ Li, X Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Luo, C Maciel, AKA Madaras, RJ Malyshev, VL Manankov, V Mao, HS Marshall, T Martin, MI Mauritz, KM Mayorov, AA McCarthy, R McMahon, T Melanson, HL Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Naumann, NA Neal, HA Negret, JP Negroni, S Nunnemann, T O'Neil, D Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Papageorgiou, K Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, O Petroff, P Piegaia, R Pope, BG Popkov, E Prosper, HB Protopopescu, S Przybycien, MB Qian, J Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Ridel, M Rijssenbeek, M Rizatdinova, F Rockwell, T Roco, M Royon, C Rubinov, P Ruchti, R Rutherfoord, J Sabirov, BM Sajot, G Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sen, N Shabalina, E Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Song, Y Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stichelbaut, F Stoker, D Stolin, V Stone, A Stoyanova, DA Strang, MA Strauss, M Strovink, M Stutte, L Sznajder, A Talby, M Taylor, W Tentindo-Repond, S Tripathi, SM Trippe, TG Turcot, AS Tuts, PM Vaniev, V Van Kooten, R Varelas, N Vertogradov, LS Villeneuve-Seguier, F Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wijngaarden, DA Willis, S Wimpenny, SJ Womersley, J Wood, DR Xu, Q Yamada, R Yamin, P Yasuda, T Yatsunenko, YA Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zhang, X Zheng, H Zhou, B Zhou, Z Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A AF Abazov, VM Abbott, B Abdesselam, A Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Ahmed, SN Alexeev, GD Alton, A Alves, GA Amos, N Anderson, EW Arnoud, Y Avila, C Baarmand, MM Babintsev, VV Babukhadia, L Bacon, TC Baden, A Baldin, BB Balm, PW Banerjee, S Barberis, E Baringer, P Barreto, J Bartlett, JF Bassler, U Bauer, A Bean, A Beaudette, F Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Beuselinck, R Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blekman, F Blessing, S Boehnlein, A Bojko, NI Borcherding, F Bos, K Bose, T Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Coney, L Connolly, B Cooper, WE Coppage, D Crepe-Renaudin, S Cummings, MAC Cutts, D Davis, GA Davis, K De, K de Jong, SJ Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Doulas, S Ducros, Y Dudko, LV Duensing, S Duflot, L Dugad, SR Duperrin, A Dyshkant, A Edmunds, D Ellison, J Eltzroth, JT Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Filthaut, F Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Fox, H Frame, KC Fu, S Fuess, S Gallas, E Galyaev, AN Gao, M Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Greenwood, ZD Grinstein, S Groer, L Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinmiller, JM Heinson, AP Heintz, U Hildreth, MD Hirosky, R Hobbs, JD Hoeneisen, B Huang, Y Iashvili, I Illingworth, R Ito, AS Jaffre, M Jain, S Jesik, R Johns, K Johnson, M Jonckheere, A Jostlein, H Juste, A Kahl, W Kahn, S Kajfasz, E Kalinin, AM Karmanov, D Karmgard, D Kehoe, R Khanov, A Kharchilava, A Kim, SK Klima, B Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kothari, B Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krivkova, P Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kupco, A Kuznetsov, VE Landsberg, G Lee, WM Leflat, A Leggett, C Lehner, F Leonidopoulos, C Li, J Li, QZ Li, X Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Luo, C Maciel, AKA Madaras, RJ Malyshev, VL Manankov, V Mao, HS Marshall, T Martin, MI Mauritz, KM Mayorov, AA McCarthy, R McMahon, T Melanson, HL Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Naumann, NA Neal, HA Negret, JP Negroni, S Nunnemann, T O'Neil, D Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Papageorgiou, K Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, O Petroff, P Piegaia, R Pope, BG Popkov, E Prosper, HB Protopopescu, S Przybycien, MB Qian, J Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Ridel, M Rijssenbeek, M Rizatdinova, F Rockwell, T Roco, M Royon, C Rubinov, P Ruchti, R Rutherfoord, J Sabirov, BM Sajot, G Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sen, N Shabalina, E Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Song, Y Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stichelbaut, F Stoker, D Stolin, V Stone, A Stoyanova, DA Strang, MA Strauss, M Strovink, M Stutte, L Sznajder, A Talby, M Taylor, W Tentindo-Repond, S Tripathi, SM Trippe, TG Turcot, AS Tuts, PM Vaniev, V Van Kooten, R Varelas, N Vertogradov, LS Villeneuve-Seguier, F Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wijngaarden, DA Willis, S Wimpenny, SJ Womersley, J Wood, DR Xu, Q Yamada, R Yamin, P Yasuda, T Yatsunenko, YA Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zhang, X Zheng, H Zhou, B Zhou, Z Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A TI The inclusive jet cross section in pp collisions at root s=1.8 TeV using the k perpendicular to algorithm SO PHYSICS LETTERS B LA English DT Article ID DEEP-INELASTIC-SCATTERING; HADRON-COLLISIONS; PARTON DISTRIBUTIONS; GLOBAL ANALYSIS; COLLIDERS AB The central inclusive jet cross section has been measured using a successive-combination algorithm for reconstruction of jets. The measurement uses 87.3 pb(-1) of data collected with the DO detector at the Fermilab Tevatron p (p) over bar Collider during 1994-1995. The cross section, reported as a function of transverse momentum (p(T) > 60 GeV) in the central region of pseudorapidity (\eta\ < 0.5), exhibits reasonable agreement with next-to-leading order QCD predictions, except at low p(T) where the agreement is marginal. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Buenos Aires, Buenos Aires, DF, Argentina. Lafex, Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Univ Estado Rio De Janeiro, Rio De Janeiro, Brazil. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Los Andes, Bogota, Colombia. Charles Univ, Ctr Particle Phys, Prague, Czech Republic. Acad Sci Czech Republ, Inst Phys, Ctr Particle Phys, Prague, Czech Republic. Univ San Francisco, Quito, Ecuador. Univ Grenoble 1, Inst Sci Nucl, CNRS, IN2P3, Grenoble, France. Univ Mediterranee, CNRS, IN2P3, CPPM, Marseille, France. CNRS, IN2P3, Lab Accelerateur Lineaire, Orsay, France. Univ Paris 06, LPNHE, Paris, France. Univ Paris 07, IN2P3, CNRS, Paris, France. CEA Saclay, Serv Phys Particules, DAPNIA, Saclay, France. Univ Mainz, Inst Phys, D-6500 Mainz, Germany. Panjab Univ, Chandigarh 160014, India. Univ Delhi, Delhi 110007, India. Tata Inst Fundamental Res, Mumbai, India. Seoul Natl Univ, Seoul, South Korea. CINVESTAV, Mexico City 14000, DF, Mexico. FOM, NIKHEF, Amsterdam, Netherlands. Univ Amsterdam, NIKHEF, Amsterdam, Netherlands. Univ Nijmegen, NIKHEF, Nijmegen, Netherlands. Inst Nucl Phys, Krakow, Poland. Joint Inst Nucl Res, Dubna, Russia. Inst Theoret & Expt Phys, Moscow 117259, Russia. Moscow MV Lomonosov State Univ, Moscow, Russia. Inst High Energy Phys, Protvino, Russia. Univ Lancaster, Lancaster, England. Univ London Imperial Coll Sci & Technol, London, England. Univ Arizona, Tucson, AZ 85721 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. Calif State Univ Fresno, Fresno, CA 93740 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Florida State Univ, Tallahassee, FL 32306 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Illinois, Chicago, IL 60607 USA. No Illinois Univ, De Kalb, IL 60115 USA. Northwestern Univ, Evanston, IL 60208 USA. Indiana Univ, Bloomington, IN 47405 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Iowa State Univ, Ames, IA 50011 USA. Univ Kansas, Lawrence, KS 66045 USA. Kansas State Univ, Manhattan, KS 66506 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Maryland, College Pk, MD 20742 USA. Boston Univ, Boston, MA 02215 USA. Northeastern Univ, Boston, MA 02115 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ Nebraska, Lincoln, NE 68588 USA. Columbia Univ, New York, NY 10027 USA. Univ Rochester, Rochester, NY 14627 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Langston Univ, Langston, OK 73050 USA. Univ Oklahoma, Norman, OK 73019 USA. Brown Univ, Providence, RI 02912 USA. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. Rice Univ, Houston, TX 77005 USA. Univ Virginia, Charlottesville, VA 22901 USA. Univ Washington, Seattle, WA 98195 USA. RP Abazov, VM (reprint author), Univ Buenos Aires, Buenos Aires, DF, Argentina. RI Sznajder, Andre/L-1621-2016; Canelli, Florencia/O-9693-2016; Alves, Gilvan/C-4007-2013; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Belyaev, Alexander/F-6637-2015; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Dudko, Lev/D-7127-2012; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Yip, Kin/D-6860-2013; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013 OI Sznajder, Andre/0000-0001-6998-1108; Canelli, Florencia/0000-0001-6361-2117; Belyaev, Alexander/0000-0002-1733-4408; Kim, Sun Kee/0000-0002-0013-0775; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; NR 16 TC 37 Z9 38 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JAN 24 PY 2002 VL 525 IS 3-4 BP 211 EP 218 DI 10.1016/S0370-2693(01)01441-1 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 513RQ UT WOS:000173393000002 ER PT J AU Rakov, VS Denisov, EV Futrell, JH Ridge, DP AF Rakov, VS Denisov, EV Futrell, JH Ridge, DP TI Surface induced dissociation of chromium hexacarbonyl ion fluorinated alkanethiolate surface in ion cyclotron resonance mass spectrometer: studies of energetics of the process using recursive internal energy distribution search method SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE surface induced dissociation; ion cyclotron resonance; self-assembled monolayers; internal energy deposition; fragment kinetic energy ID ASSEMBLED MONOLAYER FILMS; POLYATOMIC IONS; THIOL MONOLAYERS; LIQUID SURFACE; MOLECULAR-IONS; COLLISIONS; SCATTERING; GOLD; FRAGMENTATION; DECOMPOSITION AB Energy transfer in ion-surface collisional activation is characterized for 0-30 eV collisions of chromium hexacarbonyl molecular cations with a monolayer of fluorinated alkanethiolate self-assembled onto a solid gold surface. This surface was mounted on the back trapping plate of the Infinity(R) cell of a Bruker BioApex 7T ion cyclotron resonance mass spectrometer on the B-field axis orthogonal to the ion beam direction. Internal energy deposition was deduced from fragmentation spectra using a recursive internal energy distribution search method. The efficiency of energy transfer into the ion slowly increases with incident ion energy to a maximum value of 20% at about 23 eV collision energy. Approximate kinetic energy distributions of the fragments were measured by deducing the dependence of ion abundance on trapping potential. From the kinetic energy dependence on mass we infer that rapid decomposition of the molecular cation occurs after it recoils from the surface. Knowledge of both internal and kinetic energy distributions of collisionally activated ions enabled us to deduce the energy deposited into the self-assembled monolayer as a function of collision energy. (C) 2002 Elsevier Science B.V. C1 Pacific NW Natl Lab, Environment Mol Sci Lab, Richland, WA 99352 USA. Univ Delaware, Newark, DE 19716 USA. RP Futrell, JH (reprint author), Pacific NW Natl Lab, Environment Mol Sci Lab, Richland, WA 99352 USA. RI Ridge, Douglas/A-7539-2013 NR 37 TC 12 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD JAN 23 PY 2002 VL 213 IS 1 BP 25 EP 44 DI 10.1016/S1387-3806(01)00505-X PG 20 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 520RU UT WOS:000173795600004 ER PT J AU Kessinger, GF Delmore, JE AF Kessinger, GF Delmore, JE TI High temperature chemistry of molten glass ion emitters SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE thermal ionization; silica gel; molten glass; isotope ratios; ion emission mechanisms ID EARLY SOLAR-SYSTEM; REDOX REACTIONS; POLYVALENT ELEMENTS; MASS-SPECTROMETRY; SURFACE IONIZATION; THERMAL IONIZATION; SELF-DIFFUSIVITY; PBO-SIO2 MELT; THERMODYNAMICS; IRON AB Thermodynamic calculations have been performed to predict the chemical behavior of ten elements in molten borosilicate glass to gain new insights into the ion formation mechanisms for this class of ion emitters. General trends identified during the computational studies include: (1) all of the analyte elements studied are reduced, at least in part, to the elemental state (which is predicted to be soluble in the molten glass); (2) a finite percentage of each of the analytes volatizes in the elemental state, with a possibility that an electron will be stripped to form a positive ion; (3) dilution of the element in the molten glass matrix tends to reduce the evaporation rate of the analyte element for a given temperature (as compared to the pure material), allowing vaporization to occur evenly and at higher temperatures; and (4) rhenium, dissolved from the supporting filament, is predicted to be present in the molten glass. This Re is probably present as an oxide, which is believed to enhance ion emission probabilities by increasing the work function of the surface. The results of this study support the hypothesis that the ion formation mechanism for the elements investigated involves the volatilization of the element as both neutral and ionic atomic species, possibly as a Saha-Langmuir type process. Other ion emission processes are probably active for those analytes that are not easily reduced to the elemental state in the molten glass matrix. (C) 2002 Elsevier Science B.V. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Delmore, JE (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 61 TC 5 Z9 5 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD JAN 23 PY 2002 VL 213 IS 1 BP 63 EP 80 DI 10.1016/S1387-3806(01)00522-X PG 18 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 520RU UT WOS:000173795600006 ER PT J AU Lipton, AS Smith, MD Adams, RD Ellis, PD AF Lipton, AS Smith, MD Adams, RD Ellis, PD TI Zn-67 solid-state and single-crystal NMR spectroscopy and X-ray crystal structure of zinc formate dihydrate SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID CD-113 SHIELDING TENSORS; CADMIUM COMPOUNDS; COMPLEXES; PROTEINS; ANALOGS; CENTERS; MODELS AB The crystal structure, quadrupole coupling parameters, and the orientation of the electric field gradient tensors for each site of zinc formate dihydrate have been determined. There are two distinct sites in the asymmetric unit: one containing four in-plane waters with two bridging formats, the other containing six bridging formates. The solid-state NMR lineshapes have been assigned to their respective sites by using isotopic labeling and cross-polarization methods. The hydrated site corresponds to the lineshape having a quadrupole coupling constant (Cq) of 9.6 MHz and the anhydrous site has a Cq of 6,2 MHz. The absence of chemical shielding contributions to the observed lineshapes has been verified with a high-field solid-state NMR experiment performed at 18.8 T. C1 Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Macromol Struct & Dynam Directorate, Richland, WA 99352 USA. Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. RP Ellis, PD (reprint author), Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Macromol Struct & Dynam Directorate, Richland, WA 99352 USA. FU NIGMS NIH HHS [GM-26295] NR 40 TC 26 Z9 26 U1 0 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 23 PY 2002 VL 124 IS 3 BP 410 EP 414 DI 10.1021/ja011701e PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA 513AZ UT WOS:000173356900018 PM 11792210 ER PT J AU Seo, DK Corbett, JD AF Seo, DK Corbett, JD TI Synthesis, structure, and bonding of BaTI3: An unusual competition between cluster and classical bonding in the thallium layers SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ZINTL PHASES AB The new BaTl3 compound has been synthesized and characterized by physical property measurements and electronic structure calculations. Its structure (Cmcm) is a new intermediate in the Ni3Sn family (P6(3)/mmc), and consists of thallium layers formed from two-center bond formation between the parallel chains of face-sharing octahedral clusters. The valence electron concentration (VEC) of the thallium layers is consistent with their two-dimensional nature, in comparison with those in other AX(3)-type compounds with one- or three-dimensional anionic networks with the same building blocks and different VECs. The unique geometric features of the anionic thallium layers bring on an unusual competition between inter- and intracluster bonds. Detailed studies of the energetics of BaTl3 reveal for the first time the important role of cation-anion interactions in the bonding competition in such an anionic substructure. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Corbett, JD (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. NR 28 TC 14 Z9 15 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 23 PY 2002 VL 124 IS 3 BP 415 EP 420 DI 10.1021/ja011728y PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA 513AZ UT WOS:000173356900019 PM 11792211 ER PT J AU Nemes, A Pestovsky, O Bakac, A AF Nemes, A Pestovsky, O Bakac, A TI Reaction of a superoxochromium(III) ion with nitrogen monoxide: Kinetics and mechanism SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TRANSITION-METAL COMPLEXES; NITRIC-OXIDE; PEROXYNITRITE DECOMPOSITION; INDUCED OXIDATION; SUPEROXIDE; CHEMISTRY; RADICALS; ACID; NO; DIOXYGEN AB The kinetics of the rapid reaction between CraqOO2+ and NO were determined by laser flash photolysis of CraqNO2+ in O-2-saturated acidic aqueous solutions, k = 7 x 10(8) M-1 s(-1) at 25degreesC. The reaction produces an intermediate, believed to be NO2, Which was scavenged with ([14]aneN(4))Ni2+. With limiting NO, the CraqOO2+/NO reaction has a 1:1 stoichiometry and produces both free NO3- and a chromium nitrato complex, CraqONO22+. In the presence of excess NO, the stoichiometry changes to [NO]/[CraqOO2+] = 3:1, and the reaction produces close to 3 mol of nitrite/mol of CraqOO2+. An intermediate, identified as a nitritochromium(III) ion, CraqONO2+, is a precursor to a portion of free NO2- In the proposed mechanism, the initially produced peroxynitrito complex, CraqOONO2+, undergoes O-O bond homolysis followed by some known and some novel chemistry of CraqO2+ and NO2. The reaction between CraqO2+ and NO generates CraqONO2+, k > 10(4) M-1 s(-1). CraqOO2+ reacts with NO2 with k = 2.3 x 10(8) M-1 s(-1). C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Bakac, A (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 49 TC 37 Z9 37 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 23 PY 2002 VL 124 IS 3 BP 421 EP 427 DI 10.1021/ja016840a PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 513AZ UT WOS:000173356900020 PM 11792212 ER PT J AU Zhou, CH Schadler, LS Beyerlein, IJ AF Zhou, CH Schadler, LS Beyerlein, IJ TI Time-dependent micromechanical behavior in graphite/epoxy composites under constant load: a combined experimental and theoretical study SO ACTA MATERIALIA LA English DT Article DE micromechanics; micro Raman spectroscopy; composites; creep ID FIBER-REINFORCED COMPOSITES; MICRO-RAMAN SPECTROSCOPY; BROKEN FIBERS; MATRIX COMPOSITES; STRESS-RELAXATION; CREEP; DEGRADATION; EVOLUTION; INTERFACE; PROFILES AB We present an integrated theoretical and experimental study on the localized creep behavior around fiber breaks in model unidirectional graphite fiber/epoxy matrix composites under constant axial stress at room temperature. Micro Raman spectroscopy (MRS) and classic composite shear-lag models were coupled to examine the time evolution of fiber and matrix strain/stress distributions around a single fiber break in planar low volume fraction graphite fiber-epoxy matrix composites. In-situ MRS micro-scale measurements show that strain redistribution around the fiber fracture is time-dependent and localized. We observe decreases in peak interfacial shear stress and concomitant increases in load recovery length and interfacial inelastic zones from the fiber fracture point. These results showing the time dependence of load transfer are related to creep tests on the monolithic matrix material at various stress levels. The translation of monolithic to in-situ matrix creep is achieved using two viscoelastic matrix composite models, a multi-fiber and a single fiber model. MRS results show that the load recovery length increases at the rate of (T/T-c)(alpha/2) and the maximum interfacial shear stress relaxes at the rate of (T/T-c)(-alpha/2), where T is time, T-c and alpha are parameters obtained from matrix creep tests. These results are in good agreement with the multi-fiber model predictions. The single fiber model gives similar results for these samples where the fiber spacing is relatively large (5similar to7 fiber diameters). (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Rensselaer Polytech Inst, Troy, NY 12180 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schadler, LS (reprint author), Rensselaer Polytech Inst, Troy, NY 12180 USA. RI Beyerlein, Irene/A-4676-2011 NR 30 TC 14 Z9 14 U1 2 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JAN 22 PY 2002 VL 50 IS 2 BP 365 EP 377 DI 10.1016/S1359-6454(01)00353-6 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 515DL UT WOS:000173480100012 ER PT J AU Herzberg, O Chen, CCH Liu, S Tempczyk, A Howard, A Wei, M Ye, DM Dunaway-Mariano, D AF Herzberg, O Chen, CCH Liu, S Tempczyk, A Howard, A Wei, M Ye, DM Dunaway-Mariano, D TI Pyruvate site of pyruvate phosphate dikinase: Crystal structure of the enzyme-phosphonopyruvate complex, and mutant analysis SO BIOCHEMISTRY LA English DT Article ID DIRECTED MUTAGENESIS; PHOSPHOENOLPYRUVATE FORMATION; PHOSPHORYLATED ENZYME; CATALYTIC SITE; BINDING SITE; LOCATION; KINASE; IDENTIFICATION; SYSTEM; MODE AB Crystals of pyruvate phosphate dikinase in complex with a substrate analogue inhibitor, phosphonopyruvate (K-i = 3 muM), have been obtained in the presence of Mg2+. The structure has been determined and refined at 2.2 Angstrom resolution, revealing that the Mg2+-bound phosphonopyruvate binds in the alpha/beta-barrel's central channel, at the C-termini of the beta-strands. The mode of binding resembles closely the previously proposed PEP substrate binding mode, inferred by the homology of the structure (but not sequence homology) to pyruvate kinase. Kinetic analysis of site-directed mutants, probing residues involved in inhibitor binding, showed that all mutations resulted in inactivation, confirming the key role that these residues play in catalysis. Comparison between the structure of the PPDK-phosphonopyruvate complex and the structures of two complexes of pyruvate kinase, one with Mg2+-bound phospholactate and the other with Mg2+-oxalate and ATP, revealed that the two enzymes share some key features that facilitate common modes of substrate binding. There are also important structural differences, most notably, the machinery for acid/base catalysis is different. C1 Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. IIT, Chicago, IL 60616 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Herzberg, O (reprint author), Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, 9600 Gudelsky Dr, Rockville, MD 20850 USA. RI ID, IMCACAT/D-5867-2014 FU NCRR NIH HHS [1P41 RR12408-01A1]; NIGMS NIH HHS [GM36260] NR 24 TC 28 Z9 28 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JAN 22 PY 2002 VL 41 IS 3 BP 780 EP 787 DI 10.1021/bi011799+ PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 513JJ UT WOS:000173374500010 PM 11790099 ER PT J AU Kumaresan, KR Hwang, M Thelen, MP Lambert, MW AF Kumaresan, KR Hwang, M Thelen, MP Lambert, MW TI Contribution of XPF functional domains to the 5 ' and 3 ' incisions produced at the site of a psoralen interstrand cross-link SO BIOCHEMISTRY LA English DT Article ID COMPLEMENTATION GROUP-A; NUCLEOTIDE EXCISION-REPAIR; DNA ENDONUCLEASE ACTIVITIES; FANCONI-ANEMIA; ESCHERICHIA-COLI; XPF-ERCC1 COMPLEX; POLYMERASE-I; RECOMBINATION; PROTEINS; NUCLEASE AB XPF forms a heterodimeric complex with ERCC1 and is required for the repair of DNA interstrand cross-links. In association with ERCC1, it is involved in production of the 5' incision at the site of a psoralen interstrand cross-link as well as the 3' incision. The present study was carried out to determine the functional domains of XPF that are important in the production of the 5' and 3' incisions that occur at a site of a psoralen interstrand cross-link. Monoclonal antibodies (mAbs) were utilized that had been generated against polypeptide fragments of XPF and affinity-mapped to specific regions of XPF. These mAbs were examined for their ability to differentially inhibit production of dual incisions in DNA by normal human chromatin-associated protein extracts that contain XPF and ERCC1. These studies show that two regions of XPF, one N-terminal region from amino acids 12-166 and one C-terminal region from amino acids 702-854, are the most important in the production of the 5' incision. The same N-terminal region and the C-terminal region from amino acids 702-916 are also involved in the 3' incision, though to a much lesser extent. Since this C-terminal region corresponds to the proposed site of interaction of ERCC1 with XPF, these results suggest that binding of ERCC1 to XPF is critical for its ability to produce the 5' and 3' incisions at the site of an interstrand cross-link. Possibly through activation or regulation of the endonucleolytic activity of the N-terminal domain of XPF. C1 Univ Med & Dent New Jersey, New Jersey Med Sch, Dept Pathol & Lab Med, Newark, NJ 07103 USA. Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Livermore, CA 94550 USA. RP Lambert, MW (reprint author), Univ Med & Dent New Jersey, New Jersey Med Sch, Dept Pathol & Lab Med, 185 S Orange Ave, Newark, NJ 07103 USA. RI Thelen, Michael/C-6834-2008; Thelen, Michael/G-2032-2014 OI Thelen, Michael/0000-0002-2479-5480; Thelen, Michael/0000-0002-2479-5480 FU NHLBI NIH HHS [HL54806]; NIGMS NIH HHS [GM52120] NR 33 TC 18 Z9 19 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JAN 22 PY 2002 VL 41 IS 3 BP 890 EP 896 DI 10.1021/bi011613z PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 513JJ UT WOS:000173374500022 PM 11790111 ER PT J AU Xu, XD Kong, RQ de Bruijn, FJ He, SY Murry, MA Newman, T Wolk, CP AF Xu, XD Kong, RQ de Bruijn, FJ He, SY Murry, MA Newman, T Wolk, CP TI DNA sequence and genetic characterization of plasmid pFQ11 from Frankia alni strain CpI1 SO FEMS MICROBIOLOGY LETTERS LA English DT Article DE pFQ11; pFQ31; plasmid pFQ11; CpI1; Frankia alni ID ACTINORHIZAL PLANTS; PROTEIN; IDENTIFICATION; EXPRESSION; PCR AB An 8551-bp plasmid. pFQ11, from Frankia alni strain CpI1 was sequenced. Its sequence was found to be very similar to that presented for pFQ31 from strain ArI3. Six potential protein-encoding open reading frames (ORFs) were identified, and transcriptional activity was shown within four of those regions of the plasmid by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. An earlier study reported that ORF E-F of pFQ31, which is nearly identical to the 3' 45% of ORF1 of pFQ11, is significantly similar to RepF. We found no such similarity. ORF2 and ORF3 predict products that are similar to a repressor protein and a partition protein, respectively. We found inverted repeats within and covering the start codon of ORF3; palindromic sequences and direct repeats between ORF3 and ORF4; and 3' from ORF3, an AT-rich sequence that extensively overlaps the promoter region of a uvrB homolog in strain ArI3. (C) 2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved. C1 Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Microbiol & Mol Genet, E Lansing, MI 48824 USA. Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA. RP Wolk, CP (reprint author), Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. NR 23 TC 4 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1097 J9 FEMS MICROBIOL LETT JI FEMS Microbiol. Lett. PD JAN 22 PY 2002 VL 207 IS 1 BP 103 EP 107 AR PII S0378-1097(01)00566-3 DI 10.1016/S0378-1097(01)00566-3 PG 5 WC Microbiology SC Microbiology GA 530EF UT WOS:000174342100018 PM 11886759 ER PT J AU Li, X Wang, LS Cannon, NA Boldyrev, AI AF Li, X Wang, LS Cannon, NA Boldyrev, AI TI Electronic structure and chemical boning in nonstoichiometric molecules: Al3X2- (X = C,Si,Ge). A photoelectron spectroscopy and ab initio study SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TETRACOORDINATE PLANAR CARBON; GAUSSIAN-BASIS SETS; ORBITAL METHODS; ANION; ATOMS; EXCHANGE AB The electronic and molecular structure of a series of nonstoichiometric pentaatomic species, Al3X2- (X = C,Si,Ge) and their corresponding neutrals. have been studied by photoelectron spectroscopy and ab initio calculations. Well-resolved photodetachment transitions were observed for all three species and were compared with the calculations. Al3C2- was found to have a C-2v((1)A(1)) global minimum with an Al- ion coordinated to the CC triple bond in a quasi-linear AlCCAl molecule. Al3Si2- and Al3Ge2- were found to be different from the isoelectronic Al3C2- anion. They each have an almost planar trapezium global minimum structure with several low-lying isomers. The quasi-planarity of Al3Si2- and Al3Ge2- was understood by comparison with the previously known SiAl4- planar molecule. (C) 2002 American Institute of Physics. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Li, X (reprint author), Washington State Univ, Dept Phys, Richland, WA 99352 USA. RI Boldyrev, Alexander/C-5940-2009 OI Boldyrev, Alexander/0000-0002-8277-3669 NR 35 TC 19 Z9 19 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2002 VL 116 IS 4 BP 1330 EP 1338 DI 10.1063/1.1429652 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 513NG UT WOS:000173384200015 ER PT J AU Yu, HG Muckerman, JT Sears, TJ AF Yu, HG Muckerman, JT Sears, TJ TI A K-dependent adiabatic approximation to the Renner-Teller effect for triatomic molecules SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID AMPLITUDE BENDING VIBRATION; ORBITAL ANGULAR-MOMENTUM; VARIATIONAL METHOD; SINGLET METHYLENE; GEOMETRIC PHASE; SPECTROSCOPY; BROMOMETHYLENE; RESONANCES; SPECTRUM; STATES AB A K-dependent adiabatic approach is suggested to study the Renner-Teller effect in triatomic molecules using a two-dimensional Hilbert space approximation in the electronic degree of freedom. The theory is developed in hyperspherical coordinates, and approximately includes the electronic spin-orbit interaction. The adiabatic Hamiltonians are expressed in terms of a K-dependent effective potential energy surface. Eigenpairs are calculated by solving the time-independent Schrodinger equation, which is represented in a mixed grid/basis set. The method is applied to the (A) over tilde <--(X) over tilde band system of bromomethylene (H/DCBr). The results obtained show that the Renner-Teller effect in this molecule is pronounced, particularly in the excited (A) over tilde (1)A" state. The results are compared to recent experimental measurements and good agreement is found. (C) 2002 American Institute of Physics. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Yu, HG (reprint author), Brookhaven Natl Lab, Dept Chem, Bldg 555A, Upton, NY 11973 USA. RI Muckerman, James/D-8752-2013; Sears, Trevor/B-5990-2013; Yu, Hua-Gen/N-7339-2015 OI Sears, Trevor/0000-0002-5559-0154; NR 42 TC 25 Z9 25 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2002 VL 116 IS 4 BP 1435 EP 1442 DI 10.1063/1.1427707 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 513NG UT WOS:000173384200027 ER PT J AU Burnham, CJ Xantheas, SS AF Burnham, CJ Xantheas, SS TI Development of transferable interaction models for water. I. Prominent features of the water dimer potential energy surface SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LIQUID WATER; MOLECULAR-DYNAMICS; AB-INITIO; BASIS-SETS; ICE IH; CLUSTERS; HYDROGEN; SPECTRUM; ATOMS; POLARIZABILITIES AB We present an analysis of the morphology of the water dimer potential energy surface (PES) obtained from ab initio electronic structure calculations and perform a quantitative comparison with the results from various water potentials. In order to characterize the morphology of the PES we have obtained minimum energy paths (MEPs) as a function of the intermolecular O-O separation by performing constrained optimizations under various symmetries (C-s, C-i, C-2, and C-2v). These constitute a primitive map of the dimer PES and aid in providing an account for some of its salient features such as the energetic stabilization of "doubly hydrogen-bonded" configurations for R(O-O)<2.66 &ANGS;. Among the various interaction potentials that are examined, it is found that the family of anisotropic site potential (ASP) models agrees better with the ab initio results in reproducing the geometries along the symmetry-constrained MEPs. It is demonstrated that the models that produce closest agreement with the morphology of the ab initio PES, tend to better reproduce the experimental data for the second virial coefficients. We finally comment on the functional forms of simple water models and discuss how effects such as charge overlap can be incorporated into such models. (C) 2002 American Institute of Physics. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Xantheas, SS (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Xantheas, Sotiris/L-1239-2015; OI Xantheas, Sotiris/0000-0002-6303-1037 NR 53 TC 107 Z9 107 U1 2 U2 15 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2002 VL 116 IS 4 BP 1479 EP 1492 DI 10.1063/1.1423940 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 513NG UT WOS:000173384200031 ER PT J AU Xantheas, SS Burnham, CJ Harrison, RJ AF Xantheas, SS Burnham, CJ Harrison, RJ TI Development of transferable interaction models for water. II. Accurate energetics of the first few water clusters from first principles SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID WAVE-FUNCTIONS; AB-INITIO; BASIS-SETS; BINDING-ENERGIES; MP2 CALCULATIONS; HYDROGEN; HEXAMER; ATOMS; DIMER; TERMS AB We report accurate energetics for the water trimer through pentamer global ring minima and four low-lying hexamer isomers (cage, prism, book, Cyclic S-6) from first principles electronic structure calculations. The family of augmented correlation-consistent orbital basis sets of double through quintuple zeta quality was used in order to estimate complete basis set (CBS) limits for the cluster total association energies at the second order perturbation (MP2) level of theory. These are -15.8 kcal/mol (trimer), -27.6 kcal/mol (tetramer), -36.3 kcal/mol (pentamer), -45.9 kcal/mol (prism hexamer), -45.8 kcal/mol (cage hexamer), -45.6 kcal/mol (book hexamer), and -44.8 kcal/mol (ring S-6 hexamer). Effects of higher correlation, estimated at the coupled cluster plus single and double with a perturbative estimate of the triple excitations [CCSD(T)] level of theory, as well as inclusion of estimates for core-valence correlation suggest that these estimates are accurate to within 0.2 kcal/mol. (C) 2002 American Institute of Physics. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Xantheas, SS (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Xantheas, Sotiris/L-1239-2015; OI Xantheas, Sotiris/0000-0002-6303-1037 NR 28 TC 299 Z9 301 U1 2 U2 28 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2002 VL 116 IS 4 BP 1493 EP 1499 DI 10.1063/1.1423941 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 513NG UT WOS:000173384200032 ER PT J AU Burnham, CJ Xantheas, SS AF Burnham, CJ Xantheas, SS TI Development of transferable interaction models for water. III. Reparametrization of an all-atom polarizable rigid model (TTM2-R) from first principles SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RADIAL-DISTRIBUTION FUNCTIONS; MOLECULAR-DYNAMICS; AB-INITIO; POTENTIAL SURFACE; HYDROGEN-BOND; ICE IH; CLUSTERS; PAIR; DIMER; DIFFRACTION AB We present a reparametrization of an all-atom polarizable rigid model for water. The model is based on the earlier "Thole-type model" [J. Chem. Phys. 110, 4566 (1999)] and consists of a reparametrization of the two-body part of its potential energy surface from ab initio data. The new parametrization of the polarizable rigid model (TTM2-R) reproduces the structural pattern and absolute binding energies of the first few (n=2-6) water clusters to an impressive (<1%) accuracy with respect to the values obtained at the complete basis set (CBS) level of the second order perturbation theory. It also yields excellent agreement with the experimental second virial coefficient over the 423-773 K temperature range. The binding energies of the n=7-21 clusters are within 2-3% of the results with the newest version of the anisotropic site potential (ASP-W4). The new model produces a diffusion constant of 2.23 x 10(-5) cm(2) s(-1) for the liquid at 300 K and average dipole moments of 2.65 and 2.86 Debye for liquid (300 K) and ice Ih (100 K), respectively. The corresponding average internal energies are -11.21 kcal/mol/molecule for the liquid (300 K) and -14.69 kcal/mol/molecule for ice (0 K). The computed liquid radial distribution functions are in excellent agreement with experiment and the lattice constants for ice Ih are within 0.02 angstrom (<0.2%) from the experimentally obtained ones. The computed densities are 1.046 g/cm(3) for liquid water (300 K) and 0.942 g/cm(3) for ice Ih (0 K). To this end, TTM2-R is an ab initio based model that accurately reproduces both the cluster energetics and structures in addition to several bulk properties for water and ice Ih. (C) 2002 American Institute of Physics. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Xantheas, Sotiris/L-1239-2015 NR 39 TC 142 Z9 143 U1 2 U2 13 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2002 VL 116 IS 4 BP 1500 EP 1510 DI 10.1063/1.1423942 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 513NG UT WOS:000173384200033 ER PT J AU Georgievskii, Y Medvedev, ES Stuchebrukhov, AA AF Georgievskii, Y Medvedev, ES Stuchebrukhov, AA TI Proton transport via coupled surface and bulk diffusion SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PH-INDICATOR DYES; BACTERIORHODOPSIN MICELLES; CYTOPLASMIC SITES; MEMBRANE-SURFACE; PURPLE MEMBRANE; MIGRATION; DYNAMICS; TRANSLOCATION; ORIENTATION; ASSOCIATION AB Translocation of protons across biological membranes is carried out by special membrane proteins, proton pumps. Surprisingly, the turnover rate of some proton pumps, such as cytochrome c oxidase (CcO), is higher than the bulk diffusion limit (i.e., the rate at which protons can be supplied to the entrance of the proton conducting channel via free bulk diffusion). It has been suggested that the diffusion of protons along the membrane surface that surrounds the entrance of the proton conducting channel can increase the supply of the protons and therefore explain the puzzling high turnover rates. Here we consider a phenomenological model of proton transport to a proton collecting channel. The model takes into account both the diffusion in the bulk and the coupled diffusion of protons along the membrane surface. In our model a homogeneous membrane surface, which mediates proton diffusion toward the channel entrance, is populated with protolytic groups that can exchange protons with a bulk solution. Equations which describe the coupled surface-bulk proton diffusion are derived and solved. The maximum (diffusion limited) rate at which protons can be delivered to the pump is examined. It is found that there are two regimes of surface-mediated proton transport, depending on the rate of proton exchange between the bulk and the surface. In both regimes proton transport is dominated by the contribution of surface diffusion. Due to two-dimensional character of the surface diffusion, the transport rate depends on the size of the channel entrance in a weak. logarithmic fashion. The theory also provides a simple expression for the maximum distance that a proton can migrate on the surface before it is fully equilibrated with the bulk. This result allows one to examine whether the chemiosmotic coupling between a proton source on a membrane surface, such as CcO, and a sink, such as ATP synthase, occurs via diffusion along the membrane, or involves equilibration with the bulk. (C) 2002 American Institute of Physics. C1 Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. Russian Acad Sci, Inst Chem Phys, Moscow 142432, Russia. RP Sandia Natl Labs, Combust Res Facil, MS9055,POB 969, Livermore, CA 94551 USA. RI Medvedev, Emile/A-1697-2009 OI Medvedev, Emile/0000-0002-4415-6926 NR 35 TC 25 Z9 26 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2002 VL 116 IS 4 BP 1692 EP 1699 DI 10.1063/1.1428350 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 513NG UT WOS:000173384200052 ER PT J AU Donley, C Dunphy, D Paine, D Carter, C Nebesny, K Lee, P Alloway, D Armstrong, NR AF Donley, C Dunphy, D Paine, D Carter, C Nebesny, K Lee, P Alloway, D Armstrong, NR TI Characterization of indium-tin oxide interfaces using X-ray photoelectron spectroscopy and redox processes of a chemisorbed probe molecule: Effect of surface pretreatment conditions SO LANGMUIR LA English DT Article ID LIGHT-EMITTING-DIODES; THIN-FILMS; ITO; PERFORMANCE; SYSTEMS; DEVICES; ANODES; OXYGEN; LAYER AB Surface characterization of indium-tin oxide (ITO) thin films has been carried out with monochromatic X-ray photoelectron spectroscopy (XPS) following various solution pretreatments, RF air plasma etching or high-vacuum argon-ion sputtering. Commercially available ITO films show high concentrations of hydrolyzed oxides and oxy-hydroxides in the near-surface region, along with stoichiometric oxide (In2O3, SnO2) and variable levels of oxygen defect sites. XPS revealed that solution and vacuum treatments changed both the relative surface coverage of the hydroxides and, to a lesser extent, the concentration of oxide defect sites in the near-surface region. These pretreatments have a significant effect on both the coverage and electron-transfer rates for chemisorbed ferrocene dicarboxylic acid (Fc(COOH)(2)), with the air-plasma-etched ITO showing the highest surface coverage of Fc(COOH)(2) and an RCA treatment showing the highest electron-transfer rates. C1 Univ Arizona, Dept Chem, Tucson, AZ 85721 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Brown Univ, Dept Mat Sci & Engn, Providence, RI USA. RP Dunphy, D (reprint author), Univ Arizona, Dept Chem, Tucson, AZ 85721 USA. NR 41 TC 194 Z9 196 U1 8 U2 99 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 22 PY 2002 VL 18 IS 2 BP 450 EP 457 DI 10.1021/la011101t PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 514DV UT WOS:000173423700020 ER PT J AU Kono, HO Narasimhan, S Song, F Smith, DH AF Kono, HO Narasimhan, S Song, F Smith, DH TI Synthesis of methane gas hydrate in porous sediments and its dissociation by depressurizing SO POWDER TECHNOLOGY LA English DT Article DE natural gas hydrate; methane gas hydrate; synthesis of MGH in sediment; dissociation of MGH by depressurizing; reaction engineering of MGH formation and dissociation; control of porous sediments ID DECOMPOSITION; KINETICS AB The clathrate compounds of methane gas hydrate (MGH) was synthesized in laboratory at a temperature of 273.5 K and at a pressure of 6.8-13.6 MPa, consisting of solid phase MGH dispersed within various custom-designed porous sediments. This synthesized MGH looks almost like the MGH made by Mother Nature in the strata in the natural gas hydrate (NGH) field. Using this synthesized MGH, the dissociation rate was measured by depressurizing method. From experimental results, the kinetic dissociation rate equation and order of the reaction were derived. It was found through experiments that the dissociation rate could be adjusted by the control of sediment properties. With respect to MGH formation reaction, the reaction rate equation and its reaction order were also derived. (C) 2002 Elsevier Science B.V. All rights reserved. C1 W Virginia Univ, Dept Chem Engn, Morgantown, WV 26505 USA. US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP Kono, HO (reprint author), W Virginia Univ, Dept Chem Engn, POB 6102, Morgantown, WV 26505 USA. NR 13 TC 53 Z9 71 U1 7 U2 30 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD JAN 22 PY 2002 VL 122 IS 2-3 SI SI BP 239 EP 246 DI 10.1016/S0032-5910(01)00420-X PG 8 WC Engineering, Chemical SC Engineering GA 515QF UT WOS:000173506300018 ER PT J AU Cheung, MS Garcia, AE Onuchic, JN AF Cheung, MS Garcia, AE Onuchic, JN TI Protein folding mediated by solvation: Water expulsion and formation of the hydrophobic core occur after the structural collapse SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID TRANSITION-STATE; SH3 DOMAIN; MULTICANONICAL ENSEMBLE; MOLECULAR-DYNAMICS; PHASE-TRANSITIONS; GLOBULAR-PROTEINS; ENERGY LANDSCAPE; FUNNELS; SIMULATION; FRUSTRATION AB The interplay between structure-search of the native structure and desolvation in protein folding has been explored using a minimalist model. These results support a folding mechanism where most of the structural formation of the protein is achieved before water is expelled from the hydrophobic core. This view integrates water expulsion effects into the funnel energy landscape theory of protein folding. Comparisons to experimental results are shown for the SH3 protein. After the folding transition, a near-native intermediate with partially solvated hydrophobic core is found. This transition is followed by a final step that cooperatively squeezes out water molecules from the partially hydrated protein core. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Los Alamos Natl Lab, Theoret Biol & Biophys Grp, Los Alamos, NM 87545 USA. RP Onuchic, JN (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. NR 53 TC 335 Z9 342 U1 8 U2 64 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD JAN 22 PY 2002 VL 99 IS 2 BP 685 EP 690 DI 10.1073/pnas.022387699 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 514PK UT WOS:000173450100029 PM 11805324 ER PT J AU Berman, BP Nibu, Y Pfeiffer, BD Tomancak, P Celniker, SE Levine, M Rubin, GM Eisen, MB AF Berman, BP Nibu, Y Pfeiffer, BD Tomancak, P Celniker, SE Levine, M Rubin, GM Eisen, MB TI Exploiting transcription factor binding site clustering to identify cis-regulatory modules involved in pattern formation in the Drosophila genome SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID ZEBRA-STRIPE EXPRESSION; GAP GENES GIANT; SEGMENTATION GENE; ORTHODENTICLE GENE; HEAD DEVELOPMENT; CAUDAL GENE; DNA; EMBRYO; PROTEIN; ENHANCER AB A major challenge in interpreting genome sequences is understanding how the genome encodes the information that specifies when and where a gene will be expressed. The first step in this process is the identification of regions of the genome that contain regulatory information. In higher eukaryotes, this cis-regulatory information is organized into modular units [cis-regulatory modules (CRMs)] of a few hundred base pairs. A common feature of these cis-regulatory modules is the presence of multiple binding sites for multiple transcription factors. Here, we evaluate the extent to which the tendency for transcription factor binding sites to be clustered can be used as the basis for the computational identification of cis-regulatory modules. By using published DNA binding specificity data for five transcription factors active in the early Drosophila embryo, we identified genomic regions containing unusually high concentrations of predicted binding sites for these factors. A significant fraction of these binding site clusters overlap known CRMs that are regulated by these factors. In addition, many of the remaining clusters are adjacent to genes expressed in a pattern characteristic of genes regulated by these factors. We tested one of the newly identified clusters, mapping upstream of the gap gene giant (gt), and show that it acts as an enhancer that recapitulates the posterior expression pattern of gt. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Dept Genome Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley Drosophila Genome Project, Berkeley, CA 94720 USA. RP Eisen, MB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Dept Genome Sci, Mailstop 84-171,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Tomancak, Pavel/C-2109-2009; Berman, Benjamin/D-5942-2014; OI Tomancak, Pavel/0000-0002-2222-9370; Eisen, Michael/0000-0002-7528-738X; Rubin, Gerald/0000-0001-8762-8703 FU NHGRI NIH HHS [P50 HG00750]; NHLBI NIH HHS [HL667201]; NIGMS NIH HHS [GM34431, R01 GM034431] NR 55 TC 420 Z9 433 U1 1 U2 15 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD JAN 22 PY 2002 VL 99 IS 2 BP 757 EP 762 DI 10.1073/pnas.231608898 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 514PK UT WOS:000173450100041 PM 11805330 ER PT J AU Rinchik, EM Carpenter, DA Johnson, DK AF Rinchik, EM Carpenter, DA Johnson, DK TI Functional annotation of mammalian genomic DNA sequence by chemical mutagenesis: A fine-structure genetic mutation map of a 1- to 2-cM segment of mouse chromosome 7 corresponding to human chromosome 11p14-p15 SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID EMBRYONIC STEM-CELLS; DILUTION P LOCUS; N-NITROSOUREA MUTAGENESIS; UNCONVENTIONAL MYOSIN-VA; LETHAL MUTATIONS; DELETION COMPLEXES; ENU MUTAGENESIS; MOLECULAR ANALYSIS; REGION MUTATIONS; MUTANT MICE AB Eleven independent, recessive, N-ethyl-N-nitrosourea-induced mutations that map to a approximate to1- to 2-cM region of mouse chromosome (Chr) 7 homologous to human Chr 11p14-p15 were recovered from a screen of 1,218 gametes. These mutations were initially identified in a hemizygous state opposite a large p-locus deletion and subsequently were mapped to finer genomic intervals by crosses to a panel of smaller p deletions. The 11 mutations also were classified into seven complementation groups by pairwise crosses. Four complementation groups were defined by seven prenatally lethal mutations, including a group (l7R3) comprised of two alleles of obvious differing severity. Two allelic mutations (at the psrt locus) result in a severe seizure and runting syndrome, but one mutation (at the fit2 locus) results in a more benign runting phenotype. This experiment has added seven loci, defined by phenotypes of presumed point mutations, to the genetic map of a small (1-2 cM) region of mouse Chr 7 and will facilitate the task of functional annotation of DNA sequence and transcription maps both in the mouse and the corresponding human 11p14-p15 homology region. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Biochem Cellular & Mol Biol, Knoxville, TN 37996 USA. RP Rinchik, EM (reprint author), Oak Ridge Natl Lab, POB 713, Holmes, NY 12531 USA. FU NHGRI NIH HHS [HG 00370] NR 45 TC 19 Z9 19 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD JAN 22 PY 2002 VL 99 IS 2 BP 844 EP 849 DI 10.1073/pnas.022628199 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 514PK UT WOS:000173450100056 PM 11792855 ER PT J AU Arking, DE Krebsova, A Macek, M Macek, M Arking, A Mian, IS Fried, L Hamosh, A Dey, S McIntosh, I Dietz, HC AF Arking, DE Krebsova, A Macek, M Macek, M Arking, A Mian, IS Fried, L Hamosh, A Dey, S McIntosh, I Dietz, HC TI Association of human aging with a functional variant of Klotho SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID TRANSCRIPTS ENCODING MEMBRANE; MOLECULAR-CLONING; ENDOTHELIAL DYSFUNCTION; ENDOPLASMIC-RETICULUM; GENE; PROTEIN; EXPRESSION; MOUSE; MUTATION; DISEASE AB Mice deficient in Klotho gene expression exhibit a syndrome resembling premature human aging. To determine whether variation in the human KLOTHO locus contributes to survival, we applied two newly characterized polymorphic microsatellite markers flanking the gene in a population-based association study. In a cohort chosen for its homogeneity, Bohemian Czechs, we demonstrated significant differences in selected marker allele frequencies between newborn and elderly individuals (P < 0.05). These results precipitated a search for functional variants of klotho. We identified an allele, termed KL-VS, containing six sequence variants in complete linkage disequilibrium, two of which result in amino acid substitutions F352V and C370S. Homozygous elderly individuals were underrepresented in three distinct populations: Bohemian Czechs, Baltimore Caucasians, and Baltimore African-Americans [combined odds ratio (OR) = 2.59, P < 0.0023]. In a transient transfection assay, secreted levels of klotho harboring V352 are reduced 6-fold, whereas extracellular levels of the S370 form are increased 2.9-fold. The V352/S370 double mutant exhibits an intermediate phenotype (1.6-fold increase), providing a rare example of intragenic complementation in cis by human single nucleotide polymorphisms. The remarkable conservation of F352 among homologous proteins suggests that it is functionally important. The corresponding substitution, F289V, in the closest human klotho paralog with a known substrate, cBGL1, completely eliminates its ability to cleave p-nitrophenyl-beta-D-glucoside. These results suggest that the KL-VS allele influences the trafficking and catalytic activity of klotho, and that variation in klotho function contributes to heterogeneity in the onset and severity of human age-related phenotypes. C1 Johns Hopkins Univ, Sch Med, Inst Med Genet, Baltimore, MD 21205 USA. Johns Hopkins Univ, Sch Med, Howard Hughes Med Inst, Baltimore, MD 21205 USA. Johns Hopkins Univ, Sch Med, Dept Med, Baltimore, MD 21205 USA. Univ Hosp Motol, Inst Biol & Med Genet, Dept Mol Genet, Cyst Fibrosis Ctr, Prague, Czech Republic. Univ Hosp Motol, Ctr Integrated Genom, Prague, Czech Republic. Charles Univ, Sch Med 2, Prague, Czech Republic. Johns Hopkins Univ, Baltimore, MD 21218 USA. Lawrence Berkeley Natl Lab, Dept Cell & Mol Biol MS 74 197, Div Life Sci, Berkeley, CA 94720 USA. RP Dietz, HC (reprint author), Johns Hopkins Univ, Sch Med, Inst Med Genet, 720 Rutland Ave,Ross Bldg,Room 858, Baltimore, MD 21205 USA. FU NHLBI NIH HHS [R37-HL25629]; NIA NIH HHS [N0I-AG-1-2112]; NIAMS NIH HHS [R01 AR044702, AR21135, AR44702] NR 28 TC 228 Z9 242 U1 0 U2 12 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD JAN 22 PY 2002 VL 99 IS 2 BP 856 EP 861 DI 10.1073/pnas.022484299 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 514PK UT WOS:000173450100058 PM 11792841 ER PT J AU Zhang, T Zhang, YC Chu, PK Brown, IG AF Zhang, T Zhang, YC Chu, PK Brown, IG TI Wall sheath and optimal bias in magnetic filters for vacuum arc plasma sources SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS; SURFACE MODIFICATION; ION SOURCES; DEPOSITION; TRANSPORT; DUCT AB A plasma diffusion model is established to determine the optimal bias and sheath patterns in a positively biased magnetic filter of a metal arc plasma source. We determine the equation for the optimal bias on the magnetic filter. According to our model, the optimal bias is related to the electron speed, ion speed, ion mass, ion charge state, and plasma density in the filter. The optimal bias increases as these variables are increased with the exception of the electron speed. Even though the magnetic field is taken into account, it is not a variable in the final equation. Our experimental results confirm that the magnetic field has almost no influence on the optimal bias. An alternate design approach is suggested that should lead to enhanced plasma transport through the filter. (C) 2002 American Institute of Physics. C1 City Univ Hong Kong, Dept Phys & Mat Sci, Kowloon, Hong Kong, Peoples R China. Beijing Normal Univ, Beijing Radiat Ctr, Inst Low Energy Nucl Phys, Beijing 100875, Peoples R China. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Chu, PK (reprint author), City Univ Hong Kong, Dept Phys & Mat Sci, 83 Tat Chee Ave, Kowloon, Hong Kong, Peoples R China. RI Chu, Paul/B-5923-2013 OI Chu, Paul/0000-0002-5581-4883 NR 18 TC 18 Z9 20 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 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 21 PY 2002 VL 80 IS 3 BP 365 EP 367 DI 10.1063/1.1431690 PG 3 WC Physics, Applied SC Physics GA 511RB UT WOS:000173278400009 ER PT J AU Wu, L Solovyov, VF Wiesmann, HJ Zhu, Y Suenaga, M AF Wu, L Solovyov, VF Wiesmann, HJ Zhu, Y Suenaga, M TI Mechanisms for hetero-epitaxial nucleation of YBa2Cu3O similar to 6.1 at the buried precursor/SrTiO3 interface in the postdeposition reaction process SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS; YBA2CU3O7 FILMS; GROWTH; SRTIO3; DEPOSITION AB The mechanisms have been identified for the hetero-epitaxial nucleation of YBa2Cu3Osimilar to6.1 (YBCO) at the buried interface between a precursor film and SrTiO3 for the so-called BaF2 process which is a postdeposition reaction process for the synthesis of epitaxial YBCO films. It is shown that the preferential nucleation of YBCO at the interface is due to (1) the strong chemical affinity of the (Y, Ba)-oxy-fluoride, an intermediate phase, to SrTiO3 and (2) the epitaxial alignment of its (111) planes with the (001) surface of the SrTiO3 which reduces the activation barrier for the formation of YBCO. In thin films (<2-3 mum) the YBCO nuclei, whose c axes are perpendicular to the SrTiO3 surface, form directly from this aligned oxy-fluoride. In thick films (5 mum), however, this oxy-fluoride decomposes into a disordered transitory cubic phase which then orders to form YBCO nuclei with three orientational variants, one with its c axis perpendicular and two with their c axes parallel to the (001) plane of SrTiO3. (C) 2002 American Institute of Physics. C1 Brookhaven Natl Lab, Energy Sci & Technol Dept, Div Mat & Chem Sci, Upton, NY 11973 USA. RP Wu, L (reprint author), Brookhaven Natl Lab, Energy Sci & Technol Dept, Div Mat & Chem Sci, Upton, NY 11973 USA. RI Solovyov, Vyacheslav/A-7724-2009 NR 13 TC 24 Z9 27 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 21 PY 2002 VL 80 IS 3 BP 419 EP 421 DI 10.1063/1.1436285 PG 3 WC Physics, Applied SC Physics GA 511RB UT WOS:000173278400027 ER PT J AU Merkulov, VI Melechko, AV Guillorn, MA Lowndes, DH Simpson, ML AF Merkulov, VI Melechko, AV Guillorn, MA Lowndes, DH Simpson, ML TI Effects of spatial separation on the growth of vertically aligned carbon nanofibers produced by plasma-enhanced chemical vapor deposition SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD-EMISSION; NANOTUBES AB Vertically aligned carbon nanofibers (VACNFs) with vastly different spacing were grown by catalytically controlled dc glow discharge chemical vapor deposition. Both densely packed VACNFs and essentially isolated VACNFs were studied using scanning electron microscopy and x-ray energy dispersive spectroscopy. The morphology and chemical composition of isolated VACNFs were found to have a strong dependence upon the growth conditions, in particular on the C2H2/NH3 gas mixture used. This is attributed to the sidewalls of isolated VACNFs being exposed to reactive species during growth. In contrast, the sidewalls of densely packed VACNFs were shielded by the neighboring VACNFs, so that their growth occurred mainly in the vertical direction, by diffusion of carbon through the catalyst nanoparticle and subsequent precipitation at the nanofiber/nanoparticle interface. These striking differences in the growth process result in the formation of flattened carbon nanostructures (carbon nanotriangles) and also are quite important for the realization of VACNF-based devices. (C) 2002 American Institute of Physics. C1 Oak Ridge Natl Lab, Mol Scale Engn & Nanoscale Technol Res Grp, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. RP Merkulov, VI (reprint author), Oak Ridge Natl Lab, Mol Scale Engn & Nanoscale Technol Res Grp, Oak Ridge, TN 37831 USA. RI Melechko, Anatoli/B-8820-2008; Simpson, Michael/A-8410-2011; OI Simpson, Michael/0000-0002-3933-3457; Baylor, Larry/0000-0002-0325-7771 NR 12 TC 40 Z9 40 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 21 PY 2002 VL 80 IS 3 BP 476 EP 478 DI 10.1063/1.1433905 PG 3 WC Physics, Applied SC Physics GA 511RB UT WOS:000173278400046 ER PT J AU Gardner, SN AF Gardner, SN TI Modeling multi-drug chemotherapy: Tailoring treatment to individuals SO JOURNAL OF THEORETICAL BIOLOGY LA English DT Article ID ADVANCED BREAST-CANCER; ADVANCED COLORECTAL-CANCER; MONOCLONAL-ANTIBODY; CELL-PROLIFERATION; DOSE INTENSITY; COMBINATION CHEMOTHERAPY; MATHEMATICAL-MODELS; CONTINUOUS-INFUSION; GENE AMPLIFICATION; PROSTATE CARCINOMA AB Background: Predicting and tailoring optimal cancer treatments presents a major challenge. Methods: A computational model (kinetically tailored treatment, or KITT model) is developed to predict drug combinations, doses, and schedules likely to be effective in reducing tumor size and prolonging patient life. Treatment strategies may be tailored to individuals based on tumor cell kinetics. The model incorporates intra-tumor heterogeneity and evolution of drug resistance, apoptotic rates, and cell division rates. Tumor growth may follow an exponential or a Gompertzian trajectory. Drug pharmacodynamic and pharmacokinetic models are used. Toxicity is modeled in several ways. Results: A key prediction of KITT is that including cytostatic drugs like tamoxifen and herceptin during treatment with cytotoxic drugs substantially increases the probability of cure and prolongs patient life. Results also suggest that altering drug scheduling may be more effective but not more toxic than dose escalation. CAF chemotherapy (cyclophosphamide, adriamycin, and 5-fluorouracil) is predicted to be more effective than CMF (cyclophosphamide, methotrexate, and 5-fluorouracil). KITT also suggests that tumors with a high proliferative index (PI) may respond better to drug combinations incorporating two cell-cycle phase-specific drugs than do tumors with a low PI. Tumors with a low PI, in contrast, are predicted to respond better to regimens involving two cell-cycle phase-non-specific drugs than do tumors with a high PI. These predictions are borne out by clinical trial results published in the literature, which are discussed. Simulated predictions of the model match well with results from a clinical trial by Silvestrini et al. (2000. Int. J. Cancer 87, 405). The results of simulating the growth of 26 896 tumors are used to construct a decision tree for prognosis to identify the key tumor and treatment variables. Conclusion: Additional tests of the model are needed in which physicians collect information on apoptotic and proliferative indices, cell-cycle times, and drug resistance from biopsies of each individual's tumor. Computational models may become important tools to help optimize and tailor cancer treatments. (C) 2002 Academic Press. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Gardner, SN (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808,L-452, Livermore, CA 94551 USA. NR 92 TC 25 Z9 25 U1 0 U2 4 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-5193 J9 J THEOR BIOL JI J. Theor. Biol. PD JAN 21 PY 2002 VL 214 IS 2 BP 181 EP 207 DI 10.1006/jtbi.2001.2459 PG 27 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA 519VL UT WOS:000173746100005 PM 11812172 ER PT J AU Breger, M Garrido, R Handler, G Wood, MA Shobbrook, RR Bischof, KM Rodler, F Gray, RO Stankov, A Martinez, P O'Donoghue, D Szabo, R Zima, W Kaye, AB Barban, C Heiter, U AF Breger, M Garrido, R Handler, G Wood, MA Shobbrook, RR Bischof, KM Rodler, F Gray, RO Stankov, A Martinez, P O'Donoghue, D Szabo, R Zima, W Kaye, AB Barban, C Heiter, U TI 29 frequencies for the delta Scuti variable BICMi: the 1997-2000 multisite campaigns SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE techniques : photometric; stars : individual : BICMi; stars : oscillations; stars : rotation; delta Scuti ID GAMMA-DORADUS STARS; CANUM-VENATICORUM; PHOTOMETRY; PULSATION; DOMAIN AB A multisite campaign of BI CMi was carried out with excellent frequency resolution and high photometric accuracy from 1997 to 2000, including two long observing seasons. 29 pulsation frequencies could be extracted from the 1024 h (177 nights) of photometry used. The detected frequencies include 20 pulsation modes in the main pulsation frequency range from 4.8 to 13.0 cycle d(-1) (55 to 150 RHz), eight linear combinations of these frequencies, and a very low frequency at 1.66 cycle d(-1). Since the value of the low frequency at 1.66 cycle d(-1) cannot be identified with a linear combination of other frequencies, g-mode pulsation is suspected, but rotational modulation of abundance spots cannot be ruled out. BI CMi, which is situated near the cool edge of the classical instability strip, may be both a delta Scuti and a gamma Doradus star. Another outstanding property of BI CMi is the presence of a number of close frequency pairs in the power spectrum with separations as small as 0.01 cycle d(-1), A rotational velocity of v sin i = 76+/-1 km s(-1) was determined from a high-dispersion spectrum. From phase differences, the dominant modes can be identified with l values from 0 to 2. The spectral type and evolutionary status of BI CMi are examined. C1 Univ Vienna, Inst Astron, A-1180 Vienna, Austria. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. S African Astron Observ, ZA-7935 Cape Town, South Africa. Florida Inst Technol, Dept Phys & Space Sci, Melbourne, FL 32901 USA. Florida Inst Technol, SARA Observ, Melbourne, FL 32901 USA. Univ Sydney, Dept Phys, Sydney, NSW 2006, Australia. Appalachian State Univ, Dept Phys & Astron, Boone, NC 28608 USA. Konkoly Observ Budapest, H-1525 Budapest, Hungary. Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. Observ Paris, DASGAL, UMR 8633, F-92105 Meudon, France. Natl Solar Observ, Tucson, AZ 85719 USA. RP Breger, M (reprint author), Univ Vienna, Inst Astron, Turkenschanzstr 17, A-1180 Vienna, Austria. NR 22 TC 27 Z9 27 U1 1 U2 1 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JAN 21 PY 2002 VL 329 IS 3 BP 531 EP 542 DI 10.1046/j.1365-8711.2002.04970.x PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 518DV UT WOS:000173652100005 ER PT J AU Scoccimarro, R Sheth, RK AF Scoccimarro, R Sheth, RK TI PTHALOS: a fast method for generating mock galaxy distributions SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE methods : numerical; large-scale structure of Universe ID DARK-MATTER HALOES; LARGE-SCALE BIAS; GRAVITATIONAL-INSTABILITY; POWER SPECTRUM; REDSHIFT-SPACE; DENSITY PROFILE; ANALYTIC MODEL; CONDENSATION; SIMULATIONS; STATISTICS AB Current models of galaxy formation applied to understanding the large-scale structure of the Universe have two parts. The first is an accurate solution of the equations of motion for the dark matter caused by gravitational clustering. The second consists of making physically reasonable approximations to the behaviour of baryons inside dark matter haloes. The first uses large, computationally intensive, N-body simulations. We argue that because the second step is, at least at present, uncertain, it is possible to obtain similar galaxy distributions without solving the first step exactly. We describe an algorithm that is several orders of magnitude faster than N-body simulations, but that is, nevertheless, rather accurate. The algorithm combines perturbation theory with virialized halo models of the non-linear density and velocity fields. For two- and three-point statistics the resulting fields are exact on large scales, and rather accurate well into the non-linear regime, particularly for two-point statistics in real and redshift space. We then show how one can use this algorithm to generate mock galaxy distributions from halo occupation numbers. As a first application, we show that it provides a good description of the clustering of galaxies in the PSCz survey. We also discuss applications to the estimation of non-Gaussian contributions to the error bars and the covariance matrix of the power spectrum, in real and redshift space, for galaxies and dark matter. The results for the latter show good agreement with simulations, supporting the use of our method for constraining cosmological parameters from forthcoming galaxy surveys. C1 NYU, Dept Phys, New York, NY 10003 USA. NASA, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. RP Scoccimarro, R (reprint author), NYU, Dept Phys, 4 Washington Pl, New York, NY 10003 USA. NR 81 TC 104 Z9 104 U1 0 U2 1 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JAN 21 PY 2002 VL 329 IS 3 BP 629 EP 640 DI 10.1046/j.1365-8711.2002.04999.x PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 518DV UT WOS:000173652100015 ER PT J AU Pandey, SU Bellwied, R Beuttenmulller, R Caines, H Chen, W DiMassimo, D Dyke, H Elliot, D Eremin, V Grau, M Hoffmann, GW Humanic, T Ilyashenko, I Kotov, I Kraner, HW Kuczewski, P Leonhardt, B Li, Z Liaw, CJ LoCurto, G Middelkamp, P Minor, R Munhoz, M Ott, G Pruneau, C Rykov, V Schambach, J Sedlmeir, J Soja, B Sugarbaker, E Takahashi, J Wilson, K Wilson, R AF Pandey, SU Bellwied, R Beuttenmulller, R Caines, H Chen, W DiMassimo, D Dyke, H Elliot, D Eremin, V Grau, M Hoffmann, GW Humanic, T Ilyashenko, I Kotov, I Kraner, HW Kuczewski, P Leonhardt, B Li, Z Liaw, CJ LoCurto, G Middelkamp, P Minor, R Munhoz, M Ott, G Pruneau, C Rykov, V Schambach, J Sedlmeir, J Soja, B Sugarbaker, E Takahashi, J Wilson, K Wilson, R TI The silicon drift vertex detector for the STAR experiment at RHIC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 5th International Conference on Position-Sensitive Detectors CY SEP 13-17, 1999 CL UNIV COLL LONDON, LONDON, ENGLAND HO UNIV COLL LONDON DE silicon; position; detector; drift; nuclear; physics AB The current status of the STAR Silicon Vertex Tracker (SVT) is presented. The performance of the Silicon Drift Detectors (SDD) is discussed, Results for a recent 15 layer SDD tracker which prototypes all components of the SVT are presented. The enhanced physics capabilities of the STAR detector due to the addition of the SVT are addressed. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Wayne State Univ, Detroit, MI 48202 USA. Ohio State Univ, Columbus, OH 43210 USA. AF Ioffe Phys Tech Inst, St Petersburg, Russia. Univ Texas, Austin, TX 78712 USA. IHEP, RU-14284 Moscow, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Sao Paulo, Sao Paulo, Brazil. RP Pandey, SU (reprint author), Brookhaven Natl Lab, BLOG-510A-STAR,POB 5000, Upton, NY 11973 USA. RI Takahashi, Jun/B-2946-2012 OI Takahashi, Jun/0000-0002-4091-1779 NR 12 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 21 PY 2002 VL 477 IS 1-3 BP 88 EP 92 AR PII S0168-9002(01)01898-8 DI 10.1016/S0168-9002(01)01898-8 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 522FV UT WOS:000173886100017 ER PT J AU Bross, A Flattum, E Lincoln, D Grunendahl, S Warchol, J Wayne, M Padley, P AF Bross, A Flattum, E Lincoln, D Grunendahl, S Warchol, J Wayne, M Padley, P TI Characterization and performance of visible light photon counters (VLPCs) for the upgraded DO detector at the Fermilab Tevatron SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 5th International Conference on Position-Sensitive Detectors CY SEP 13-17, 1999 CL UNIV COLL LONDON, LONDON, ENGLAND HO UNIV COLL LONDON AB The upgraded DO detector at the Tevatron collider will use about 100 000 pixels of Visible Light Photon Counters (VLPCs) readout for its scintillating fiber tracker and preshower detectors. VLPCs are solid state photudetectors that are operated at the temperature of a few degrees Kelvin. capable of detecting single photons. All VLPC chips were characterized in the presence of a 20 MHz background of photoelectrons. The acceptance rate was 87%. The operating bias ranges from 5.8 to 8.0 V. the gain from 20 000 to 60 000, and the threshold from 5 to 15 CC. All 8 pixels belonging to one chip have very similar efficiencies. thresholds and gains. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Rice Univ, Bonner Nucl Lab, Houston, TX 77251 USA. RP Warchol, J (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. NR 9 TC 22 Z9 22 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 21 PY 2002 VL 477 IS 1-3 BP 172 EP 178 AR PII S0168-9002(01)01884-8 DI 10.1016/S0168-9002(01)01884-8 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 522FV UT WOS:000173886100031 ER PT J AU Casagrande, L Abreu, MC Bell, WH Berglund, P de Boer, W Borchi, E Borer, K Bruzzi, M Buontempo, S Chapuy, S Cindro, V Collins, P D'Ambrosio, N Da Via, C Devine, S Dezillie, B Dimcovski, Z Eremin, V Esposito, A Granata, V Grigoriev, E Hauler, F Heijne, E Heising, S Janos, S Jungermann, L Konorov, I Li, Z Lourenco, C Mikuz, M Niinikoski, TO O'Shea, V Pagano, S Palmieri, VG Paul, S Pirollo, S Pretzl, K Rato, P Ruggiero, G Smith, K Sonderegger, P Sousa, P Verbitskaya, E Watts, S Zavrtanik, M AF Casagrande, L Abreu, MC Bell, WH Berglund, P de Boer, W Borchi, E Borer, K Bruzzi, M Buontempo, S Chapuy, S Cindro, V Collins, P D'Ambrosio, N Da Via, C Devine, S Dezillie, B Dimcovski, Z Eremin, V Esposito, A Granata, V Grigoriev, E Hauler, F Heijne, E Heising, S Janos, S Jungermann, L Konorov, I Li, Z Lourenco, C Mikuz, M Niinikoski, TO O'Shea, V Pagano, S Palmieri, VG Paul, S Pirollo, S Pretzl, K Rato, P Ruggiero, G Smith, K Sonderegger, P Sousa, P Verbitskaya, E Watts, S Zavrtanik, M TI Radiation hard cryogenic silicon detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 5th International Conference on Position-Sensitive Detectors CY SEP 13-17, 1999 CL UNIV COLL LONDON, LONDON, ENGLAND HO UNIV COLL LONDON DE cryogenic silicon detectors; Lazarus effect ID CHARGE COLLECTION EFFICIENCY; TEMPERATURES AB It has been recently observed that heavily irradiated silicon detectors, no longer functional at room temperature, "resuscitate" when operated at temperatures below 130 K. This is often referred to as the "Lazarus effect". The results presented here show that cryogenic operation represents a new and reliable solution to the problem of radiation tolerance of silicon detectors. (C) 2002 Elsevier Science B.V. All rights reserved. C1 LIP, P-1000 Lisbon, Portugal. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Helsinki Univ Technol, Low Temp Lab, FIN-02150 Espoo, Finland. Univ Karlsruhe, IEKP, D-76128 Karlsruhe, Germany. Univ Florence, Dipartimento Emerget, I-50121 Florence, Italy. Univ Bern, LHEP, CH-3012 Bern, Switzerland. Univ Naples Federico II, Dipartimento Fis, Naples, Italy. Ist Nazl Fis Nucl, I-80125 Naples, Italy. Univ Geneva, Dept Radiol, CH-1211 Geneva 4, Switzerland. JSI, Expt Particle Phys Dept, Ljubljana, Slovenia. CERN, CH-1211 Geneva 23, Switzerland. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Brookhaven Natl Lab, Upton, NY 11973 USA. AF Ioffe Phys Tech Inst, St Petersburg, Russia. Tech Univ Munich, D-8046 Garching, Germany. RP Casagrande, L (reprint author), CERN EP, CH-1211 Geneva 23, Switzerland. RI Zavrtanik, Marko/A-1524-2008; Rato Mendes, Pedro/F-8827-2010; Grigoriev, Eugene/K-6650-2013; O'Shea, Val/G-1279-2010; Verbitskaya, Elena/D-1521-2014; Bruzzi, Mara/K-1326-2015; Paul, Stephan/F-7596-2015; Paul, Stephan/K-9237-2016; OI Abreu, Maria Conceicao/0000-0003-0093-7496; Pagano, Sergio/0000-0001-6894-791X; Zavrtanik, Marko/0000-0001-5606-6912; Rato Mendes, Pedro/0000-0001-9929-0869; Grigoriev, Eugene/0000-0001-7235-9715; O'Shea, Val/0000-0001-7183-1205; Bruzzi, Mara/0000-0001-7344-8365; Paul, Stephan/0000-0002-8813-0437; Paul, Stephan/0000-0002-8813-0437; D'Ambrosio, Nicola/0000-0001-9849-8756 NR 7 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 21 PY 2002 VL 477 IS 1-3 BP 299 EP 303 AR PII S0168-9002(01)01863-0 DI 10.1016/S0168-9002(01)01863-0 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 522FV UT WOS:000173886100052 ER PT J AU Ashmanskas, W Bardi, A Bari, M Belforte, S Berryhill, J Bogdan, M Cerri, A Clark, AG Chlachidze, G Condorelli, R Culberston, R Dell'Orso, M Donati, S Frisch, HJ Galeotti, S Giannetti, P Glagolev, V Leger, A Meschi, E Morsani, F Nakaya, T Punzi, G Ristori, L Sanders, H Semenov, A Signorelli, G Shochet, M Speer, T Spinella, F Wilson, P Wu, X Zanetti, A AF Ashmanskas, W Bardi, A Bari, M Belforte, S Berryhill, J Bogdan, M Cerri, A Clark, AG Chlachidze, G Condorelli, R Culberston, R Dell'Orso, M Donati, S Frisch, HJ Galeotti, S Giannetti, P Glagolev, V Leger, A Meschi, E Morsani, F Nakaya, T Punzi, G Ristori, L Sanders, H Semenov, A Signorelli, G Shochet, M Speer, T Spinella, F Wilson, P Wu, X Zanetti, A TI The CDF silicon vertex tracker SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 5th International Conference on Position-Sensitive Detectors CY SEP 13-17, 1999 CL UNIV COLL LONDON, LONDON, ENGLAND HO UNIV COLL LONDON DE trigger; DAQ; real time pattern recognition; silicon detectors AB Real time pattern recognition is becoming a key issue in many position sensitive detector applications. The CDF collaboration is building SVT: a specialized electronic device designed to perform real time track reconstruction using the Silicon VerteX detector (SVX II). This will strongly improve the CDF capability of triggering on events containing b quarks, usually characterized by the presence of a secondary vertex. SVT is designed to reconstruct in real time charged particles trajectories using data coming from the silicon vertex detector and the central outer tracker drift chamber. The SVT architecture and algorithm have been specially tuned to minimize processing time without degrading parameter resolution. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Ist Nazl Fis Nucl, Pisa, Italy. Univ Pisa, Pisa, Italy. Joint Inst Nucl Res, Dubna, Russia. Univ Geneva, Geneva, Switzerland. Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Scuola Normale Super Pisa, Pisa, Italy. Ist Nazl Fis Nucl, Trieste, Italy. Univ Chicago, Chicago, IL 60637 USA. RP Cerri, A (reprint author), Ist Nazl Fis Nucl, San Piero Grado, I-56010 Pisa, Italy. RI Zanetti, Anna/I-3893-2012; Punzi, Giovanni/J-4947-2012; Belforte, Stefano/J-5843-2012; Signorelli, Giovanni/L-5405-2016 OI Punzi, Giovanni/0000-0002-8346-9052; Signorelli, Giovanni/0000-0001-8262-8245 NR 4 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 21 PY 2002 VL 477 IS 1-3 BP 451 EP 455 AR PII S0168-9002(01)01830-7 DI 10.1016/S0168-9002(01)01830-7 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 522FV UT WOS:000173886100079 ER PT J AU Kim, S Kaminker, P Campisi, J AF Kim, S Kaminker, P Campisi, J TI Telomeres, aging and cancer: In search of a happy ending SO ONCOGENE LA English DT Review DE antagonistic pleiotropy; cellular senescence; genomic instability; immortalization; telomerase; tumor suppression ID NORMAL HUMAN FIBROBLASTS; NORMAL HUMAN-CELLS; HUMAN TUMOR-CELLS; POLY(ADP-RIBOSE) POLYMERASE; REPLICATIVE SENESCENCE; CELLULAR SENESCENCE; LENGTH REGULATION; LIFE-SPAN; MAMMALIAN TELOMERES; MOUSE TELOMERASE AB Telomeres are distinctive structures, composed of a repetitive DNA sequence and associated proteins, that cap the ends of linear chromosomes. Telomeres are essential for maintaining the integrity and stability of eukaryotic genomes. In addition, under some circumstances, telomeres can influence cellular gene expression. In mammals, the length, structure, and function of telomeres have been proposed to contribute to cellular and organismal phenotypes associated with cancer and aging. Here, we discuss what is known about the basis for the links between telomeres, aging and cancer, and some of the known and proposed consequences of telomere dysfunction and maintenance for mammalian cells and organisms. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Mailstop 84-171,1 Cyclotron Rd, Berkeley, CA 94720 USA. EM JCAMPISI@LBL.GOV NR 105 TC 137 Z9 150 U1 2 U2 13 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0950-9232 EI 1476-5594 J9 ONCOGENE JI Oncogene PD JAN 21 PY 2002 VL 21 IS 4 BP 503 EP 511 DI 10.1038/sj.onc.1205077 PG 9 WC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity GA 513QU UT WOS:000173390500002 ER PT J AU de la Fuente, OR Zimmerman, JA Gonzalez, MA de la Figuera, J Hamilton, JC Pai, WW Rojo, JM AF de la Fuente, OR Zimmerman, JA Gonzalez, MA de la Figuera, J Hamilton, JC Pai, WW Rojo, JM TI Dislocation emission around nanoindentations on a (001) fcc metal surface studied by scanning tunneling microscopy and atomistic simulations SO PHYSICAL REVIEW LETTERS LA English DT Article ID AU(001) AB We present a combined study by scanning tunneling microscopy and atomistic simulations of the emission of dissociated dislocation loops by nanoindentation on a (001) fcc surface. The latter consist of two stacking-fault ribbons bounded by Shockley partials and a stair-rod dislocation. These dissociated loops, which intersect the surface, are shown to originate from loops of interstitial character emitted along the [110] directions and are usually located at hundreds of angstroms away from the indentation point. Simulations reproduce the nucleation and glide of these dislocation loops. C1 Univ Complutense, Dept Fis Mat, E-28040 Madrid, Spain. Sandia Natl Labs, Livermore, CA 94550 USA. Natl Taiwan Univ, Ctr Condensed Matter Sci, Taipei 106, Taiwan. RP de la Fuente, OR (reprint author), Univ Complutense, Dept Fis Mat, E-28040 Madrid, Spain. RI de la Figuera, Juan/E-7046-2010; Rodriguez, Oscar/B-7118-2011; Zimmerman, Jonathan/A-8019-2012 OI de la Figuera, Juan/0000-0002-7014-4777; Rodriguez, Oscar/0000-0002-6888-459X; NR 18 TC 114 Z9 114 U1 2 U2 18 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 21 PY 2002 VL 88 IS 3 AR 036101 DI 10.1103/PhysRevB.88.036101 PG 4 WC Physics, Multidisciplinary SC Physics GA 514UV UT WOS:000173460200026 ER PT J AU Maingi, R Bell, MG Bell, RE Bush, CE Fredrickson, ED Gates, DA Kaye, SM Kugel, HW LeBlanc, BP Menard, JE Mueller, D Sabbagh, SA Stutman, D Taylor, G Johnson, DW Kaita, R Maqueda, RJ Ono, M Paoletti, F Paul, SF Peng, YKM Roquemore, AL Skinner, CH Soukhanovskii, VA Synakowski, EJ AF Maingi, R Bell, MG Bell, RE Bush, CE Fredrickson, ED Gates, DA Kaye, SM Kugel, HW LeBlanc, BP Menard, JE Mueller, D Sabbagh, SA Stutman, D Taylor, G Johnson, DW Kaita, R Maqueda, RJ Ono, M Paoletti, F Paul, SF Peng, YKM Roquemore, AL Skinner, CH Soukhanovskii, VA Synakowski, EJ TI Characteristics of the first H-mode discharges in the National Spherical Torus Experiment SO PHYSICAL REVIEW LETTERS LA English DT Article ID PLASMAS; TOKAMAK AB We report observations of the first low-to-high (L-H) confinement mode transitions in the National Spherical Torus Experiment. The H-mode energy confinement time increased over reference discharges transiently by 100-200%, as high as similar to100 ms. This confinement time is similar to2 times higher than predicted by a multimachine scaling. Thus the confinement time of spherical tori has been extended to a record high value, leading to an eventual revision of confinement scalings. Finally, the power threshold for H-mode access is >10 X higher than predicted by an international scaling from conventional aspect-ratio tokamaks, which could lead to new understanding of H-mode transition dynamics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Columbia Univ, New York, NY USA. Johns Hopkins Univ, Baltimore, MD USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Maingi, R (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Sabbagh, Steven/C-7142-2011; Stutman, Dan/P-4048-2015 NR 21 TC 21 Z9 21 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 21 PY 2002 VL 88 IS 3 AR 035003 DI 10.1103/PhysRevB.88.035003 PG 4 WC Physics, Multidisciplinary SC Physics GA 514UV UT WOS:000173460200020 PM 11801067 ER PT J AU Minko, S Muller, M Usov, D Scholl, A Froeck, C Stamm, M AF Minko, S Muller, M Usov, D Scholl, A Froeck, C Stamm, M TI Lateral versus perpendicular segregation in mixed polymer brushes SO PHYSICAL REVIEW LETTERS LA English DT Article ID SURFACE; SEPARATION; LAYER; FILMS; THIN AB Grafting of incompatible polymers on a substrate prevents macrophase separation and the chains self-assemble laterally. Mixed brushes are exposed to different solvents and the morphology is observed via atomic force and x-ray photoemission microscopy. In a nonselective solvent the different species segregate into parallel cylinders ("ripple structure"). Upon exposure to a selective solvent, we encounter a transition to a "dimple" structure, in which the unfavored component forms clusters. Simultaneously, we observe an enhanced perpendicular segregation. The experimental observations are compared to self-consistent field calculations, where qualitative agreement is found. C1 Inst Polymerforsch Dresden EV, D-01005 Dresden, Germany. Johannes Gutenberg Univ Mainz, Inst Phys, WA 331, D-55099 Mainz, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Minko, S (reprint author), Inst Polymerforsch Dresden EV, Postfach 12 04 11, D-01005 Dresden, Germany. RI Minko, Sergiy/A-9458-2009; Muller, Marcus/B-9898-2009; Umlauf, Ursula/D-3356-2014; Scholl, Andreas/K-4876-2012 OI Minko, Sergiy/0000-0002-7747-9668; Muller, Marcus/0000-0002-7472-973X; NR 18 TC 160 Z9 160 U1 2 U2 38 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 21 PY 2002 VL 88 IS 3 AR 035502 DI 10.1103/PhysRevLett.88.035502 PG 4 WC Physics, Multidisciplinary SC Physics GA 514UV UT WOS:000173460200022 PM 11801069 ER PT J AU Singleton, J Goddard, PA Ardavan, A Harrison, N Blundell, SJ Schlueter, JA Kini, AM AF Singleton, J Goddard, PA Ardavan, A Harrison, N Blundell, SJ Schlueter, JA Kini, AM TI Test for interlayer coherence in a quasi-two-dimensional superconductor SO PHYSICAL REVIEW LETTERS LA English DT Article ID SMALL CLOSED ORBITS; HIGH MAGNETIC-FIELDS; QUASI-2-DIMENSIONAL CONDUCTORS; MAGNETORESISTANCE OSCILLATIONS; ORGANIC CONDUCTORS; LAYERED METALS; FERMI-SURFACE; KAPPA-(BEDT-TTF)(2)CU(NCS)(2); STATE AB Peaks in the magnetoresistivity of the layered superconductor kappa - (BEDT-TTF)(2)Cu(NCS)(2), measured in fields less than or equal to45 T applied within the layers, show that the Fermi surface is extended in the interlayer direction and enable the interlayer transfer integral (t(perpendicular to) approximate to0.04 meV) to be deduced. However, the quasi-particle scattering rate tau(-1) is such that (h) over bar/tau similar to 6t(perpendicular to), implying that kappa - (BEDT-TTF)(2)Cu(NCS)(2) meets the criterion used to identify interlayer incoherence. The applicability of this criterion to anisotropic materials is thus shown to be questionable. C1 LANL, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Singleton, J (reprint author), LANL, Natl High Magnet Field Lab, MS-E536, Los Alamos, NM 87545 USA. RI Kini, Aravinda/F-4467-2012; Goddard, Paul/A-8638-2015 OI Goddard, Paul/0000-0002-0666-5236 NR 30 TC 72 Z9 72 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 21 PY 2002 VL 88 IS 3 AR 037001 DI 10.1103/PhysRevB.88.037001 PG 4 WC Physics, Multidisciplinary SC Physics GA 514UV UT WOS:000173460200034 PM 11801081 ER PT J AU Smakov, J Martin, I Balatsky, AV AF Smakov, J Martin, I Balatsky, AV TI Theory of scanning tunneling microscopy measurement of single spin decoherence in a superconductor SO PHYSICAL REVIEW LETTERS LA English DT Article AB Localized spin states in conventional superconductors at low temperatures are expected to have a long decoherence time due to the strong suppression of spin relaxation channels. We propose a scanning tunneling microscopy (STM) experiment allowing the direct measurement of the decoherence time of a single spin in a conventional superconductor. The experimental setup can be readily applied to general-purpose spin-polarized STM and to local spin relaxation spectroscopy. A possible extension of the setup to a quantum information processing scheme is discussed. C1 Royal Inst Technol SCFAB, Dept Phys, SE-10691 Stockholm, Sweden. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Smakov, J (reprint author), Royal Inst Technol SCFAB, Dept Phys, SE-10691 Stockholm, Sweden. NR 14 TC 8 Z9 8 U1 1 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 21 PY 2002 VL 88 IS 3 AR 037003 DI 10.1103/PhysRevLett.88.037003 PG 4 WC Physics, Multidisciplinary SC Physics GA 514UV UT WOS:000173460200036 ER PT J AU Nieto, MM AF Nieto, MM TI Existence of bound states in continuous 0 < D < infinity dimensions SO PHYSICS LETTERS A LA English DT Article ID EXTRA DIMENSIONS; ZERO-ENERGY; GRAVITY; SUPERSYMMETRY; POTENTIALS; COULOMB AB In modern fundamental theories there is consideration of higher dimensions, often in the context of what can be written as a Schrodinger equation. Thus, the energetics of bound states in different dimensions is of interest. By considering the quantum square well in continuous D dimensions, it is shown that there is always a bound state for 0 < D less than or equal to 2. This binding is complete for D --> 0 and exponentially small for D --> 2-. For D > 2, a finite-sized well is always needed for there to be a bound state. This size grows like D-2 as D gets large. By adding the proper angular momentum tail, a volcano, zero-energy, bound state can be obtained. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Los Alamos Natl Lab, Theoret Div, Los Alamos, NM 87545 USA. RP Nieto, MM (reprint author), Los Alamos Natl Lab, Theoret Div, POB 1663 MS-B285, Los Alamos, NM 87545 USA. NR 29 TC 21 Z9 21 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD JAN 21 PY 2002 VL 293 IS 1-2 BP 10 EP 16 DI 10.1016/S0375-9601(01)00827-1 PG 7 WC Physics, Multidisciplinary SC Physics GA 518CN UT WOS:000173649200002 ER PT J AU Kasen, D Branch, D Baron, E Jeffery, D AF Kasen, D Branch, D Baron, E Jeffery, D TI A complete analytic inversion of supernova lines in the Sobolev approximation SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : formation; line : identification; line : profiles; radiative transfer; supernovae : general ID EXPANDING ATMOSPHERES; H-ALPHA; EMISSION; SPECTRUM; EJECTA; WINDS AB We show that the shape of P Cygni line profiles of photospheric-phase supernova can be analytically inverted to extract both the optical depth and the source function of the line-i.e., all the physical content of the model for the case when the Sobolev approximation is valid. Under various simplifying assumptions, we derive formulae that give S(r) and tau(r) in terms of derivatives of the line flux with respect to wavelength. The transition region between the minimum and the maximum of the line profile turns out to give especially interesting information on the optical depth near the photosphere. The formulae give insights into the relationship between line shape and physical quantities that may be useful in interpreting observed spectra and detailed numerical calculations. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. New Mexico Inst Min & Technol, Dept Phys, Socorro, NM 87801 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM dnkasen@panisse.lbl.gov; branch@mail.nhn.ou.edu; baron@mail.nhn.ou.edu; jeffery@kestrel.nmt.edu RI Baron, Edward/A-9041-2009 OI Baron, Edward/0000-0001-5393-1608 NR 20 TC 6 Z9 6 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2002 VL 565 IS 1 BP 380 EP 384 DI 10.1086/324136 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 515QP UT WOS:000173507200033 ER PT J AU Fryer, CL Holz, DE Hughes, SA AF Fryer, CL Holz, DE Hughes, SA TI Gravitational wave emission from core collapse of massive stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE black hole physics; gravitational waves; stars : neutron; supernovae : general ID ROTATING RELATIVISTIC STARS; ACCRETION-INDUCED COLLAPSE; MAGNETIC NEUTRON-STARS; R-MODE OSCILLATIONS; GAMMA-RAY BURSTS; WHITE-DWARFS; BLACK-HOLE; SUPERNOVA EXPLOSIONS; ANGULAR-MOMENTUM; IA SUPERNOVAE AB We derive estimates for the characteristics of gravitational radiation from stellar collapse, using recent models of the core collapse of Chandrasekhar-massed white dwarfs (accretion-induced collapse), core-collapse supernovae and collapsars, and the collapse of very massive stars (greater than or similar to300 M-circle dot). We study gravitational wave emission mechanisms using several estimation techniques, including two-dimensional numerical computation of quadrupole wave emission, estimates of bar-mode strength, estimates of r-mode emission, and estimates of waves from black hole ringing. We also review the rate at which the relevant collapses are believed to occur, which has a major impact on their relevance as astrophysical sources. Although the latest supernova progenitor simulations produce cores rotating much slower than those used in the past, we find that bar-mode and r-mode instabilities from core-collapse supernovae remain among the leading candidate sources for second-generation detectors at the Laser Interferometer Gravitational-Wave Observatory (LIGO II). Accretion-induced collapse (AIC) of a white dwarf could produce gravitational wave signals similar to those from core collapse. In the models that we examine, such collapses are not unstable to bar modes; we note that models recently examined by Liu & Lindblom, which have slightly more angular momentum, are certainly unstable to bar formation. Because AIC events are probably 1000 times less common than core-collapse supernovae, the typical AIC event will be much farther away, and thus the observed waves will be much weaker. In the most optimistic circumstances, we find that it may be possible to detect gravitational waves from the collapse of 300 M-circle dot Population III stars. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. EM clf@t6-serv.lanl.gov; deholz@itp.ucsb.edu; hughes@itp.ucsb.edu NR 67 TC 133 Z9 134 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2002 VL 565 IS 1 BP 430 EP 446 DI 10.1086/324034 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 515QP UT WOS:000173507200038 ER PT J AU Cruddace, RG Kowalski, MP Yentis, D Brown, CM Gursky, H Barstow, MA Bannister, NP Fraser, GW Spragg, JE Lapington, JS Tandy, JA Sanderson, B Culhane, JL Barbee, TW Kordas, JF Goldstein, W Fritz, GG AF Cruddace, RG Kowalski, MP Yentis, D Brown, CM Gursky, H Barstow, MA Bannister, NP Fraser, GW Spragg, JE Lapington, JS Tandy, JA Sanderson, B Culhane, JL Barbee, TW Kordas, JF Goldstein, W Fritz, GG TI High-resolution spectroscopy of G191-B2B in the extreme-ultraviolet SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; ISM : general; stars : individual (G191-B2B); white dwarfs ID DA WHITE-DWARFS; MODEL ATMOSPHERES; DISCOVERY; SPECTRUM; FEIGE-24; ELEMENTS AB We report a high-resolution ( R = 3000-4000) spectroscopic observation of the DA white dwarf G191-B2B in the extreme-ultraviolet band 220-245 Angstrom. A low-density, ionized He component is clearly present along the line of sight, which if completely interstellar implies a He ionization fraction considerably higher than is typical of the local interstellar medium. However, some of this material may be associated with circumstellar gas, which has been detected by analysis of the C IV absorption-line doublet in a Hubble Space Telescope/Space Telescope Imaging Spectrograph spectrum. A stellar atmosphere model assuming a uniform element distribution yields a best fit to the data that includes a significant abundance of photospheric He. The 99% confidence contour for the fit parameters excludes solutions in which photospheric He is absent, but this result needs to be tested using models allowing abundance gradients. C1 USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Lawrence Livermore Natl Lab, Livermore, CA USA. Praxis Inc, Alexandria, VA 22314 USA. RP Cruddace, RG (reprint author), USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. RI Lapington, Jon/A-7669-2012 NR 19 TC 26 Z9 26 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 20 PY 2002 VL 565 IS 1 BP L47 EP L50 DI 10.1086/339054 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 515QR UT WOS:000173507400012 ER PT J AU Tymczak, CJ Niklasson, AMN Roder, H AF Tymczak, CJ Niklasson, AMN Roder, H TI Separable and nonseparable multiwavelets in multiple dimensions SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE multiwavelets; multidimensional; lifting scheme; polynonimal interpolation ID ELECTRONIC-STRUCTURE CALCULATIONS; 2-SCALE DIFFERENCE-EQUATIONS; COMPACTLY SUPPORTED WAVELETS; ORTHONORMAL BASES; FILTER BANKS; ALGORITHMS; REGULARITY AB We report on a method of constructing multidimensional biorthogonal interpolating multiwavelets. The approach is based upon polynomial interpolation in R-d (C, de Boor and A. Ron, Math. Comput. 58, 198 (1997)) and an extension of the lifting scheme (J. Kovacevic and W. Sweldens, IEEE Trans. Image Process. 9, No. 3, 480 (2000)). The constructed wavelets have compact support, are nearly isotropic, and retain partial scale invariance leading to a fast and efficient multidimensional wavelet transform. We demonstrate an implementation for these wavelets of variable polynomial order up to four dimensions. Finally, we show that these wavelets have a much sparser representation of discontinuous functions as compared to tensor product wavelets, which allows for a more compact and efficient representation. (C) 2002 Elsevier Science (USA). C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Tymczak, CJ (reprint author), Los Alamos Natl Lab, Div Theoret, MS B221, Los Alamos, NM 87545 USA. NR 38 TC 5 Z9 7 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JAN 20 PY 2002 VL 175 IS 2 BP 363 EP 397 DI 10.1006/jcph.2001.6743 PG 35 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 520TF UT WOS:000173796900001 ER PT J AU Adib, K Camillone, N Fitts, JP Rim, KT Flynn, GW Joyce, SA Osgood, RM AF Adib, K Camillone, N Fitts, JP Rim, KT Flynn, GW Joyce, SA Osgood, RM TI CCl4 chemistry on the magnetite selvedge of single-crystal hematite: competitive surface reactions SO SURFACE SCIENCE LA English DT Article DE molecule-solid reactions; thermal desorption spectroscopy; surface chemical reaction; surface relaxation and reconstruction; iron oxide; single crystal surfaces ID SCANNING-TUNNELING-MICROSCOPY; ALPHA-FE2O3(0001) SURFACES; CARBON-TETRACHLORIDE; FE3O4(111); ADSORPTION; WATER; OXIDE; GALLIUM-ARSENIDE(110); DEPENDENCE; DESORPTION AB Temperature programmed reaction/desorption (TPR/D) studies were undertaken to characterize the surface chemistry which occurs between CCl4 and the Fe3O4 (111) selvedge of single crystal alpha-Fe2O3 (0 0 0 1). Six separate desorption events are clearly observed and four desorbing species are identified: CO4, OCCl2, C2O4 and FeCl2. It is proposed that OCCl2, CCl4 and C2O4 are produced in reactions involving the same precursor, CCl2. Three reaction paths compete for the CCl2 precursor: oxygen atom abstraction (for OCCl2,), molecular recombinative desorption (for CCl4) and associative desorption (for C2Cl4). During the TPR/D temperature ramp, the branching ratio is observed to depend upon temperature and the availability of reactive sites. The data are consistent with a rich site-dependent chemistry. (C) 2001 Published by Elsevier Science B.V. C1 Columbia Univ, Dept Appl Phys & Appl Math, Mat Sci Program, New York, NY 10027 USA. Columbia Univ, Environm Mol Sci Inst, New York, NY 10027 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Osgood, RM (reprint author), Columbia Univ, Dept Elect Engn, 530 W 120th St, New York, NY 10027 USA. RI Fitts, Jeffrey/J-3633-2012; Joyce, Stephen/Q-7804-2016 OI Joyce, Stephen/0000-0003-1330-7362 NR 38 TC 27 Z9 27 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JAN 20 PY 2002 VL 497 IS 1-3 BP 127 EP 138 DI 10.1016/S0039-6028(01)01635-1 PG 12 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 519QP UT WOS:000173737200014 ER PT J AU Yan, XM Hang, W Majidi, V Marrone, BL Yoshida, TM AF Yan, XM Hang, W Majidi, V Marrone, BL Yoshida, TM TI Evaluation of different nucleic acid stains for sensitive double-stranded DNA analysis with capillary electrophoretic separation SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE detection; electrophoresis; DNA; dyes; poly (vinylpyrrolidone); SYTOX orange; SYTO 82; SYTO 25; ethidium bromide; propidium iodide ID INDUCED FLUORESCENCE DETECTION; POLYMERASE CHAIN-REACTION; HIGH-RESOLUTION SEPARATION; TANDEM REPEAT LOCI; RESTRICTION FRAGMENTS; POLY(VINYLPYRROLIDONE) SOLUTION; ARRAY ELECTROPHORESIS; INTERCALATING DYES; REACTION PRODUCTS; FLOW-CYTOMETRY AB This paper outlines the first use of SYTOX Orange, SYTO 82 and SYTO 25 nucleic acid stains for on-column staining of double-stranded DNA dsDNA) fragments separated by capillary electrophoresis (CE). Low-viscosity, replaceable poly(v (vinylpyrrolidone) (PVP) polymer solution was used as the sieving matrix on an uncoated fused-silica capillary. The effects of PVP concentration, electric Field strength, and incorporated nucleic acid stain concentrations on separation efficiency were examined for a wide range of DNA fragment sizes. Our study was focused on using nucleic acid stains efficiently excitable at a wavelength of 532 nm. Among the five tested nucleic acid stains, SYTOX Orange stain was shown to have the best sensitivity For dsDNA detection by CE. About a 500-fold lower detection limit was obtained compared to commonly used ethidium bromide and propidium iodide. SYTOX Orange stain also provided a wide linear dynamic range for direct DNA quantitation with on-line CE detection. Use of SYTOX Orange stain can greatly improve the measurement of DNA fragments by CE, which will enable an expanded set of applications in genomics and diagnostics. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Yoshida, TM (reprint author), Los Alamos Natl Lab, Div Chem, POB 1663, Los Alamos, NM 87545 USA. NR 31 TC 17 Z9 18 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JAN 18 PY 2002 VL 943 IS 2 BP 275 EP 285 DI 10.1016/S0021-9673(01)01452-2 PG 11 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 510RV UT WOS:000173221800010 PM 11833647 ER PT J AU Kevrekidis, PG Kevrekidis, IG Malomed, BA AF Kevrekidis, PG Kevrekidis, IG Malomed, BA TI Stability of solitary waves in finite Ablowitz-Ladik lattices SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article ID EIGENVALUE PROBLEMS; DISCRETE-SYSTEMS; BOUND-STATES; EQUATIONS; PULSES; BIFURCATION; DYNAMICS; MODES AB We discuss the effects of different types of boundary conditions (b.c.) on the linear stability of a solitary wave in a finite-length dynamical lattice described by the Ablowitz-Ladik (AL) model. Types of b.c. considered are 'fixed' (Dirichlet), no-flux (Neumann) and free as well as periodic b.c. The behaviour of eigenvalues around a stationary nonlinear wave consistent with several types of b.c. is studied analytically and numerically. The translational eigenvalues are found to move away from the origin. It is shown that for b.c. of the 'fixed' type, these eigenvalues bifurcate into a neutrally stable (oscillatory) kind, while the no-flux and free b.c. lead to an exponentially weak instability. The 'rotational' eigenmodes (those related to the gauge invariance of the lattice) strictly remain at the origin, as gauge invariance is not broken by the linear homogeneous b.c. These (numerical) results are compared to the analytical and semi-analytical predictions obtained within the approximation of the images generated by the solitary wave beyond the lattice edges. A potential effect of continuous-spectrum band-edge bifurcations on stability is also evaluated, with the conclusion that that these bifurcations cannot destabilize the 'soliton', For periodic b.c., the translational invariance is preserved, and so is the Lax-pair structure, sustaining the integrable nature of the problem. The AL model was chosen so that the effects of boundary conditions are monitored in the absence of non-integrable discreteness. Finally, the possibility of the generation of multipulse configurations, due to the interplay of finiteness effects with the exponential tail-tail interaction of the pulses, is examined. C1 Univ Massachusetts, Dept Math & Stat, Amherst, MA 01003 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Princeton Univ, Dept Chem Engn, Princeton, NJ 08544 USA. Princeton Univ, Program Appl & Computat Math, Princeton, NJ 08544 USA. Tel Aviv Univ, Fac Engn, Dept Interdisciplinary Studies, IL-69978 Tel Aviv, Israel. RP Kevrekidis, PG (reprint author), Univ Massachusetts, Dept Math & Stat, Lederle Grad Res Tower, Amherst, MA 01003 USA. NR 29 TC 4 Z9 4 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD JAN 18 PY 2002 VL 35 IS 2 BP 267 EP 283 AR PII S0305-4470(02)25718-2 DI 10.1088/0305-4470/35/2/307 PG 17 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 560GX UT WOS:000176075300009 ER PT J AU Hoffman, JE Hudson, EW Lang, KM Madhavan, V Eisaki, H Uchida, S Davis, JC AF Hoffman, JE Hudson, EW Lang, KM Madhavan, V Eisaki, H Uchida, S Davis, JC TI A four unit cell periodic pattern of quasi-particle states surrounding vortex cores in Bi2Sr2CaCu2O8+delta SO SCIENCE LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; D-WAVE SUPERCONDUCTORS; ELECTRONIC-STRUCTURE; PHASE-DIAGRAM; STRIPE PHASES; MIXED-STATE; DENSITY; ORDER; MODEL; LINES AB Scanning tunneling microscopy is used to image the additional quasi-particle states generated by quantized vortices in the high critical temperature superconductor Bi2Sr2CaCu2O8+delta. They exhibit a copper-oxygen bond-oriented "checkerboard" pattern, with four unit cell (4a(o)) periodicity and a similar to30 angstrom decay length. These electronic modulations may be related to the magnetic field-induced, 8a(o) periodic, spin density modulations with decay length of similar to70 angstroms recently discovered in La1.84Sr0.16CuO4. The proposed explanation is a spin density wave localized surrounding each vortex core, General theoretical principles predict that, in the cuprates, a localized spin modulation of wavelength X should be associated with a corresponding electronic modulation of wavelength lambda/2, in good agreement with our observations. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Tokyo, Dept Superconduct, Tokyo 1138656, Japan. RP Davis, JC (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM jcdavis@socrates.berkeley.edu RI Hudson, Eric/C-2746-2008; Hoffman, Jennifer/H-4334-2011 OI Hudson, Eric/0000-0001-7064-0351; Hoffman, Jennifer/0000-0003-2752-5379 NR 32 TC 571 Z9 573 U1 9 U2 63 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 EI 1095-9203 J9 SCIENCE JI Science PD JAN 18 PY 2002 VL 295 IS 5554 BP 466 EP 469 DI 10.1126/science.1066974 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 512YG UT WOS:000173350700040 PM 11799234 ER PT J AU Jeong, B Kim, SW Bae, YH AF Jeong, B Kim, SW Bae, YH TI Thermosensitive sol-gel reversible hydrogels SO ADVANCED DRUG DELIVERY REVIEWS LA English DT Review DE aqueous polymer solution; sol-gel transition; in situ hydrogel formation; temperature; drug delivery ID BIODEGRADABLE BLOCK-COPOLYMERS; MODIFIED POLY(ACRYLIC ACID); OXIDE) TRIBLOCK COPOLYMER; DRUG-DELIVERY SYSTEMS; AQUEOUS-SOLUTIONS; CONTROLLED-RELEASE; THERMOREVERSIBLE GELATION; IN-SITU; POLY(ETHYLENE GLYCOL); LIGHT-SCATTERING AB Aqueous polymer solutions that are transformed into gels by changes in environmental conditions, such as temperature and pH, thus resulting in in situ hydrogel formation, have recently attracted the attention of many investigators for scientific interest and for practical biomedical or pharmaceutical applications. When the hydrogel is formed under physiological conditions and maintains its integrity for a desired period of time, the process may provide various advantages over conventional hydrogels. Because of the simplicity of pharmaceutical formulation by solution mixing, biocompatibility with biological systems, and convenient administration, the pharmaceutical and biomedical uses of the water-based sol-gel transition include solubilization of low-molecular-weight hydrophobic drugs, controlled release, labile biomacromolecule delivery, such as proteins and genes, cell immobilization, and tissue engineering. When the formed gel is proven to be biocompatible and biodegradable, producing non-toxic degradation products, it will provide further benefits for in vivo applications where degradation is desired. It is timely to summarize the polymeric systems that undergo sol-gel transitions, particularly due to temperature, with emphasis on the underlying transition mechanisms and potential delivery aspects. This review stresses the polymeric systems of natural or modified natural polymers, N-isopropylacrylamide copolymers, poly(ethylene oxide)/poly(propylene oxide) block copolymers, and poly(ethylene glycol)/poly(D,L-lactide-co-glycolide) block copolymers. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Utah, Dept Pharmaceut & Pharmaceut Chem, Ctr Controlled Chem Delivery, Salt Lake City, UT 84112 USA. PNNL, Richland, WA 99352 USA. RP Bae, YH (reprint author), Univ Utah, Dept Pharmaceut & Pharmaceut Chem, Ctr Controlled Chem Delivery, Salt Lake City, UT 84112 USA. EM yhbae@kjist.ac.kr NR 95 TC 874 Z9 918 U1 75 U2 648 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-409X J9 ADV DRUG DELIVER REV JI Adv. Drug Deliv. Rev. PD JAN 17 PY 2002 VL 54 IS 1 BP 37 EP 51 DI 10.1016/S0169-409X(01)00242-3 PG 15 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 517AU UT WOS:000173589600004 PM 11755705 ER PT J AU Bowman, RC Lindensmith, CA Luo, S Flanagan, TB Vogt, T AF Bowman, RC Lindensmith, CA Luo, S Flanagan, TB Vogt, T TI Degradation behavior of LaNi5-xSnxHz (x=0.20-0.25) at elevated temperatures SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2000) CY OCT 01-06, 2000 CL NOOSA HEADS, AUSTRALIA DE La-Ni-Sn alloys; CaCu5 phases; P-C isotherms; non-stoichiometric alloys; hydride degradation behavior; X-ray diffraction ID SYSTEM; ISOTHERMS; HYDRIDES; ALLOYS AB Systematic studies of the hydriding behavior of LaNi5-xSnx alloys with tin contents in the range 0.20 1000 h) at elevated temperatures and hydrogen pressure to produce further degradation in the P-C-T isotherms. The impact of alloy composition on the isotherms has been determined. The crystal lattice properties of the alloys before and after hydrogen reactions have been studied using high-resolution X-ray powder diffraction with synchrotron radiation. Changes in these X-ray diffraction patterns are correlated to various structural modifications resulting from hydride formation and degradation. (C) 2002 Elsevier Science B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Vermont, Dept Chem, Burlington, VT 05405 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Bowman, RC (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Vogt, Thomas /A-1562-2011; OI Vogt, Thomas /0000-0002-4731-2787; Bowman, Robert/0000-0002-2114-1713 NR 19 TC 32 Z9 32 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 17 PY 2002 VL 330 BP 271 EP 275 DI 10.1016/S0925-8388(01)01521-3 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 508KT UT WOS:000173087800054 ER PT J AU Majer, G Gottwald, J Peterson, DT Barnes, RG AF Majer, G Gottwald, J Peterson, DT Barnes, RG TI Model-independent measurements of hydrogen diffusivity in the yttrium dihydrides SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2000) CY OCT 01-06, 2000 CL NOOSA HEADS, AUSTRALIA DE hydrogen diffusivity; yttrium dihydrides; pulsed-field-gradient nuclear magnetic resonance ID NUCLEAR-MAGNETIC-RESONANCE; SITE OCCUPANCY; NMR; TRIHYDRIDE; SYSTEMS; H-2; YHX AB The hydrogen diffusivities D in yttrium. dihydrides YHx., have been measured by means of pulsed-field-gradient nuclear magnetic resonance (PFG-NMR) up to 920 K for x = 1.91 and up to 620 K for x = 1.95 and 2.03. The observed D values are generally significantly greater than those in the dihydrides of titanium and zirconium. The activation enthalpy H-a, obtained by fitting an Arrhenius expression to the diffusivities, decreases substantially with increasing x from H-a = 0.53 eV (x = 1.91) to H-a = 0.38 eV (x = 2.03). Measurements of the proton spin-lattice relaxation Gamma(1) have been performed on the same samples. The temperature and concentration dependences of the dipolar relaxation Gamma(1d) are consistent with the PFG results. Besides Gamma(1d) and the electronic relaxation Gamma(1e), the Gamma(1) data reveal contributions due to very small concentrations of paramagnetic impurities Gamma1p, which dominate the measured rates below about 500 K, even at impurity levels as low as 20 ppm or less. (C) 2002 Published by Elsevier Science B.V. C1 Max Planck Inst Met Res, D-70569 Stuttgart, Germany. US DOE, Ames Lab, Dept Phys, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Majer, G (reprint author), Max Planck Inst Met Res, Heisenbergstr 1, D-70569 Stuttgart, Germany. NR 26 TC 8 Z9 8 U1 1 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 17 PY 2002 VL 330 BP 438 EP 442 DI 10.1016/S0925-8388(01)01452-9 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 508KT UT WOS:000173087800090 ER PT J AU Gross, KJ Thomas, GJ Jensen, CM AF Gross, KJ Thomas, GJ Jensen, CM TI Catalyzed alanates for hydrogen storage SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2000) CY OCT 01-06, 2000 CL NOOSA HEADS, AUSTRALIA DE metal hydride; complex hydride; catalysis; NAlH4; Na3AlH6; hydrogen storage; fuel cell ID WALLED CARBON NANOTUBES; SODIUM ALUMINUM-HYDRIDE; METAL HYDRIDES; DECOMPOSITION AB The discovery that hydrogen can be reversibly absorbed and desorbed from complex hydrides (the alanates) by the addition of catalysts has created an entirely new prospect for lightweight hydrogen storage. Unlike the interstitial intermetallic hydrides, these compounds release hydrogen through a series of decomposition /recombination reactions e.g.: NaAlH(4)double left right arrow1/3Na(3)AIH(6) + 2/3Al+H(2)double left right arrowNaH+Al+3/ 2H(2). Initial work resulted in improved catalysts, advanced methods of preparation, and a better understanding of the hydrogen absorption and desorption processes. Recent studies have clarified some of the fundamental material properties, as well as the engineering characteristics of catalyst enhanced sodium alanate. Phase transitions were observed real-time through in situ X-ray powder diffraction. These measurements demonstrate that the decomposition reactions occur through long-range transport of metal species. SEM imaging and EDS analysis verified the segregation of aluminum to the surface of the material during decomposition. The equilibrium thermodynamics of decomposition have now been measured down to room temperature. They show a plateau pressure for the first reaction of I bar at 33degreesC, which suggest that, thermodynamically, this material is ideally suited to on-board hydrogen storage for fuel cell vehicles. Room temperature desorption with slow but measurable kinetics has been recorded for the first time. Studies at temperatures approaching that found in the operation of PEM fuel cells (125-165degreesC) were performed on a scaled-up test bed. The bed demonstrated surprisingly good kinetics and other positive material properties. However, these studies also pointed to the need to develop new non-alkoxide based catalysts and doping methods to increase the capacity and reduce the level of hydrocarbon impurities found in the desorbed hydrogen. For this reason, new Ti-Cl catalysts and doping processes are being developed which show higher capacities and improved kinetics. An overview of the current state-of-the-art will be presented along with our own studies and the implications for the viability of these materials in on-board hydrogen storage applications. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Analyt Mat Sci Dept, Livermore, CA 94551 USA. Univ Hawaii Manoa, Dept Chem, Honolulu, HI 96822 USA. RP Sandia Natl Labs, Analyt Mat Sci Dept, POB 695,MS 9403, Livermore, CA 94551 USA. EM kjgross@sandia.gov NR 40 TC 204 Z9 208 U1 5 U2 32 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 EI 1873-4669 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 17 PY 2002 VL 330 BP 683 EP 690 DI 10.1016/S0925-8388(01)01586-9 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 508KT UT WOS:000173087800138 ER PT J AU Gross, KJ Sandrock, G Thomas, GJ AF Gross, KJ Sandrock, G Thomas, GJ TI Dynamic in situ X-ray diffraction of catalyzed alanates SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2000) CY OCT 01-06, 2000 CL NOOSA HEADS, AUSTRALIA DE metal hydride; complex hydride; hydrogen storage; fuel cell; NaAlH4; Na(3)AIH(6) ID REVERSIBLE HYDROGEN STORAGE; SODIUM ALUMINUM-HYDRIDE AB The discovery that hydrogen can be reversibly absorbed and desorbed from NaAlH4 by the addition of catalysts has created an entirely new prospect for lightweight hydrogen storage. NaAlH4 releases hydrogen through the following set of decomposition reactions: NaAlH4 --> (1)/(3)(alpha-Na3AlH6) + (2)/Al-3 + H-2 --> NaH + Al + (3)/H-2(2) These decomposition reactions as well as the reverse recombination reactions were directly observed using time-resolved in situ X-ray powder diffraction. These measurements were performed under conditions similar to those found in PEM fuel cell operations (hydrogen absorption, 50-70degreesC, 10-15 bar H-2; hydrogen desorption, 80-110degreesC, 5-100 mbar H-2). Catalyst doping was found to dramatically improve kinetics under these conditions. In this study, the alanate was doped with a catalyst by dry ball-milling NaAlH4 with 2 mol.% solid TiCl3 X-ray diffraction clearly showed that TiCl3 reacts with NaAlH4 to form NaCl during the doping process. Partial desorption of NaAlH4 was even observed to occur during the catalyst doping process. Published by Elsevier Science B.V. C1 Sandia Natl Labs, Analyt Mat Sci Dept, Livermore, CA 94551 USA. SunaTech Inc, Ringwood, NJ 07456 USA. RP Gross, KJ (reprint author), Sandia Natl Labs, Analyt Mat Sci Dept, POB 969,MS 9403, Livermore, CA 94551 USA. NR 14 TC 74 Z9 74 U1 1 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 17 PY 2002 VL 330 BP 691 EP 695 DI 10.1016/S0925-8388(01)01463-3 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 508KT UT WOS:000173087800139 ER PT J AU Sandrock, G Gross, K Thomas, G Jensen, C Meeker, D Takara, S AF Sandrock, G Gross, K Thomas, G Jensen, C Meeker, D Takara, S TI Engineering considerations in the use of catalyzed sodium alanates for hydrogen storage SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2000) CY OCT 01-06, 2000 CL NOOSA HEADS, AUSTRALIA DE hydrogen absorbing materials; sodium alanates; NaAlH4; Na3AlH6; desorption kinetics; engineering properties ID ALUMINUM HYDRIDES AB The hydrogen storage properties of catalyzed NaAlH4 (and associated Na3AlH6) were studied in relation to various practical engineering considerations. Properties measured were cyclic capacity, charging and discharging rates, thermal effects, gaseous impurities, volume changes, low temperature plateau pressures and detailed isothermal desorption kinetics over the temperature range 23-180degreesC. Two materials were evaluated, one mechanically milled with the liquid alkoxides Ti(OBun)(4) and Zr(OPri)(4) and one milled with dry TiCl, as catalyst precursors. The alkoxide-catalyzed materials had low reversible capacities and released significant levels of hydrocarbon impurities during H-2 discharge. These problems were virtually eliminated with the inorganic TiCl3 catalyst precursor. The NaAlH4 and Na3AlH6 decomposition kinetics of TiCl3-catalyzed Na-alanate conform to Arrhenius behavior with activation energies of 79.5 and 97 kJ/mol H-2, respectively. Measured absorption and desorption kinetics were surprisingly good and it is shown that 3-4.5 wt.% H-2 can be stored and recovered in reasonable times at 100-125degreesC. It may even be ultimately possible to use the NaAlH4 decomposition reaction to provide 3 wt.% H-2 at room temperature for low-rate applications. Published by Elsevier Science B.V. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Univ Hawaii, Dept Chem, Honolulu, HI 96822 USA. SunaTech Inc, Ringwood, NJ 07456 USA. RP Sandrock, G (reprint author), Sandia Natl Labs, POB 969,MS 9402, Livermore, CA 94551 USA. RI Takara, Satoshi/A-1484-2011 NR 13 TC 127 Z9 128 U1 1 U2 18 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 17 PY 2002 VL 330 BP 696 EP 701 DI 10.1016/S0925-8388(01)01505-5 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 508KT UT WOS:000173087800140 ER PT J AU Thomas, GJ Gross, KJ Yang, NYC Jensen, C AF Thomas, GJ Gross, KJ Yang, NYC Jensen, C TI Microstructural characterization of catalyzed NaAlH4 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2000) CY OCT 01-06, 2000 CL NOOSA HEADS, AUSTRALIA DE metal hydride; complex hydride; hydrogen storage; NaAlH4; Na3AlH6; electron microscopy ID REVERSIBLE HYDROGEN STORAGE; SODIUM ALUMINUM-HYDRIDE AB A number of laboratories have now demonstrated that catalyst-assisted NaAlH4 can reversibly absorb and desorb hydrogen in the solid state at moderate temperatures. An understanding of the mechanisms by which bulk decomposition and reformation of the compound can occur in the presence of a surface catalyst is important to improving the kinetic and thermodynamic properties of alanates for use in hydrogen storage applications. Using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), we have examined the microstructure and elemental composition of Na alanate samples, doped using a liquid Ti/Zr catalyst precursor, for a number of conditions. First, microscopy and compositional analyses were performed at different stages of the decomposition process within the first desorption cycle. Second, the material was characterized after multiple absorption/desorption cycles (five cycles). Finally, the effects of the catalyst doping procedure on particle size, surface morphology and surface composition were examined. Significant changes in particle morphology and in elemental distribution were found to be induced by the desorption and cycling processes. Importantly, our measurements indicate that the initial dehydriding reactions were accompanied by significant enhancement of Al concentration toward the surface of particles and that elemental segregation occurred with repeated absorption/desorption cycles. (C) 2002 Published by Elsevier Science B.V. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Univ Hawaii, Dept Chem, Honolulu, HI 96822 USA. RP Thomas, GJ (reprint author), 537 Spirit Ridge Court, Reno, NV 89511 USA. NR 8 TC 91 Z9 95 U1 2 U2 16 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 17 PY 2002 VL 330 BP 702 EP 707 DI 10.1016/S0925-8388(01)01538-9 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 508KT UT WOS:000173087800141 ER PT J AU Hanneken, JW Baker, DB Conradi, MS Eastman, JA AF Hanneken, JW Baker, DB Conradi, MS Eastman, JA TI NMR study of the nanocrystalline palladium-hydrogen system SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2000) CY OCT 01-06, 2000 CL NOOSA HEADS, AUSTRALIA DE metals; nanostructures; nuclear resonances; grain boundaries ID DIFFUSION; PD AB Proton nuclear magnetic resonance spectra of nanocrystalline n-PdH0.7 at room temperature reveal two distinct, motionally-narrowed peaks, attributed to crystallite interstitial and interfacial hydrogen populations. In addition, proton spin-lattice relaxation measurements show enhanced relaxation rates. Both results are qualitatively consistent with a previously-observed hydrogen concentration enhancement in grain boundaries of alpha-phase n-PdHx. Magnetization recovery data for n-PdH0.7 also reveal that the separate populations of hydrogen do not exchange on time scales of up to order 0.1 s, a surprising result considering the correlation time associated with spin-lattice relaxation, of order 10(-8) s. (C) 2002 Elsevier Science B.V. All rights reserved. C1 William Jewell Coll, Dept Phys, Liberty, MO 64068 USA. Univ Memphis, Dept Phys, Memphis, TN 38152 USA. Washington Univ, Dept Phys 1105, St Louis, MO 63130 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Baker, DB (reprint author), William Jewell Coll, Dept Phys, 500 Coll Hill, Liberty, MO 64068 USA. RI Eastman, Jeffrey/E-4380-2011; OI Eastman, Jeff/0000-0002-0847-4265 NR 27 TC 15 Z9 15 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 17 PY 2002 VL 330 BP 714 EP 717 DI 10.1016/S0925-8388(01)01498-0 PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 508KT UT WOS:000173087800143 ER PT J AU Larson, EJ Cook, KJ Wermer, JR Tuggle, DG AF Larson, EJ Cook, KJ Wermer, JR Tuggle, DG TI Nitriding reactions with a Zr-Mn-Fe metal getter SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2000) CY OCT 01-06, 2000 CL NOOSA HEADS, AUSTRALIA DE intermetallics; gas-solid reactions; X-ray diffraction ID GAS STREAMS; TRITIUM; ALLOY; HYDROGEN; ZR2FE; PURIFICATION; ABSORPTION; REDUCTION; RECOVERY AB The metal getter Zr-Mn-Fe (SAES ST909) is an important component of a metal hydride-based tritium clean-up system at Los Alamos National Laboratory (LANL). The system is normally used to clean a glovebox with a helium/nitrogen atmosphere. During start-up operations, it was found that the Zr-Mn-Fe alloy exhibited an anomaly during activation, namely an exotherm upon initial exposure to nitrogen. The purpose of this work is to better understand this nitriding reaction. Nitrogen absorption studies, temperature profile experiments, and powder X-ray diffraction (XRD) were used to study the nitriding reaction. An exothermic reaction between nitrogen and ST909 was observed at similar to450degreesC only when the getter was heated for the first time. ST909 that had been previously heated without nitrogen did not produce an exotherm when heated a second time with nitrogen. Based on the XRD evidence, it was speculated that nitrogen reacts exothermically with the zirconium in the ST909 material. After heating above similar to660degreesC, the aluminum binder in the ST909 melts and may alloy with the zirconium. The resulting alloy appears to be less reactive with nitrogen and does not produce an exotherm. Published by Elsevier Science B.V. C1 Los Alamos Natl Lab, Engn Sci & Applicat Div, Tritium Sci & Engn Grp, Los Alamos, NM 87545 USA. RP Larson, EJ (reprint author), Los Alamos Natl Lab, Engn Sci & Applicat Div, Tritium Sci & Engn Grp, Mailstop C927, Los Alamos, NM 87545 USA. NR 12 TC 6 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 17 PY 2002 VL 330 BP 897 EP 901 DI 10.1016/S0925-8388(01)01499-2 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 508KT UT WOS:000173087800179 ER PT J AU Dang, LX Chang, TM AF Dang, LX Chang, TM TI Molecular mechanism of ion binding to the liquid/vapor interface of water SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Letter ID VAPOR INTERFACE; DYNAMICS; POTENTIALS AB We have carried out extensive molecular dynamics simulations to study the electrostatic surface potentials and molecular mechanism of iodide binding to the liquid/vapor interface of water using both nonpolarizable and polarizable potential models. Both simulated electrostatic surface potentials are negative with a value of about -0.50 +/- 0.01 V. The simulated results are compared to the experimental estimates of the surface potentials ranging from -1.1 V to 0.4 V. This paper contributes to a better understanding of the molecular mechanisms of ion binding to the liquid/vapor interface of water. A free energy minimum was observed near the Gibbs dividing surface for simulations that employed polarizable models. In contrast, simulations that used nonpolarizabic models provided no surface state as the iodide crossed the liquid/vapor interface of water. Corroborating observations were recently reported by Finlayson-Pitts and co-workers (Knipping, E. M.; Lakin, M. J.; Foster, K. L.; Jungwirth, P.; Tobias, D. J.; Gerber, R. B.; Daddub, D.; Finlayson-Pitts Science 2000, 301, 288) using different approaches. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Wisconsin Parkside, Dept Chem, Kenosha, WI 53141 USA. RP Dang, LX (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. NR 12 TC 223 Z9 223 U1 3 U2 29 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 17 PY 2002 VL 106 IS 2 BP 235 EP 238 DI 10.1021/jp011853w PG 4 WC Chemistry, Physical SC Chemistry GA 513BB UT WOS:000173357100002 ER PT J AU Dreger, ZA Gruzdkov, YA Gupta, YA Dick, JJ AF Dreger, ZA Gruzdkov, YA Gupta, YA Dick, JJ TI Shock wave induced decomposition chemistry of pentaerythritol tetranitrate single crystals: Time-resolved emission spectroscopy SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ORIENTATION DEPENDENCE; THERMAL-DECOMPOSITION; ELECTRONIC-STRUCTURE; NITRATE ESTERS; AB-INITIO; NITROMETHANE; SENSITIVITY; DETONATION; INITIATION; SPECTRUM AB The decomposition mechanism in shocked pentaerythritol tetranitrate (PETN) was examined using time-resolved emission spectroscopy. PETN single crystals were subjected to stepwise loading along [100] and [110] to peak stresses between 2 and 13 GPa. Due to concurrent changes in the optical transmission of PETN, emission spectra were analyzed using the absorption data acquired separately under the same loading conditions. Analyses of the corrected emission data revealed two bands in the spectra at similar to3.0 and similar to2.4 eV. Both bands were observed in every experiment regardless of stress or crystal orientation. However, their relative and absolute intensities, and temporal behavior revealed stress and orientation dependence. The emission was identified as chemiluminescence from the nitronium ion, NO(2)(+), on the basis of its electronic structure and properties. NO(2)(+) electronic structure was analyzed using ab initio calculations, which showed transition energies matching those of the emitting intermediate observed experimentally. Several chemical pathways compatible with the formation of NO(2)(+) are considered and evaluated. Finally, a four-step chemical initiation mechanism in shocked crystalline PETN is proposed and discussed in detail. C1 Washington State Univ, Inst Shock Phys, Pullman, WA 99164 USA. Washington State Univ, Dept Phys, Pullman, WA 99164 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Gupta, YA (reprint author), Washington State Univ, Inst Shock Phys, Pullman, WA 99164 USA. NR 48 TC 56 Z9 57 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 17 PY 2002 VL 106 IS 2 BP 247 EP 256 DI 10.1021/jp011682v PG 10 WC Chemistry, Physical SC Chemistry GA 513BB UT WOS:000173357100004 ER PT J AU LaVerne, JA Tandon, L AF LaVerne, JA Tandon, L TI H-2 production in the radiolysis of water on CeO2 and ZrO2 SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SILICA NANOPARTICLE/WATER INTERFACE; HYDROGEN GAS-FORMATION; MOLECULAR-HYDROGEN; HEAVY-IONS; TRANSPORT-PROPERTIES; PLUTONIUM DIOXIDE; LIQUID WATER; NUCLEAR-FUEL; ELECTRON; UO2 AB The production of H-2 in the radiolysis of water adsorbed on micron-sized particles of CeO2 and ZrO2 has been examined. Radiation chemical yields of H-2 increase substantially with decreasing number of adsorbed water layers when the yield is determined with respect to the energy deposited directly by gamma-rays to the water. These yields reached values of 20 and 150 molecules of H-2 per 100 eV for one to two water layers on CeO2 and ZrO2, respectively, compared to 0.45 molecule/100 eV in bulk liquid water. The yields of H-2 determined with respect to the total energy deposited in both the oxide and water were found to have a smaller, but observable, dependence on the amount of water adsorbed. Radiolysis of ZrO2 With gamma-rays produced about 5 times more H-2 than CeO2 for the equivalent amount of water adsorbed. The results suggest that the increase in H-2 production is due to the transfer of energy, possibly by an exciton, from the oxide to the water. O-2 production was at least an order of magnitude less than H-2. The yield of H-2 in the 5 MeV helium ion radiolysis of water on CeO2 is the same as with gamma-rays, but the results with ZrO2 are substantially lower. The H-2 yields with helium ion radiolysis may be nearly independent of the type of oxide. C1 Univ Notre Dame, Radiat Lab, Notre Dame, IN 46556 USA. Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP LaVerne, JA (reprint author), Univ Notre Dame, Radiat Lab, Notre Dame, IN 46556 USA. NR 69 TC 58 Z9 58 U1 5 U2 24 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 17 PY 2002 VL 106 IS 2 BP 380 EP 386 DI 10.1021/jp013098s PG 7 WC Chemistry, Physical SC Chemistry GA 513BB UT WOS:000173357100023 ER PT J AU Chialvo, AA Houssa, M Cummings, PT AF Chialvo, AA Houssa, M Cummings, PT TI Molecular dynamics study of the structure and thermophysical properties of model sI clathrate hydrates SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID INTERMOLECULAR POTENTIAL FUNCTIONS; VAPOR COEXISTENCE CURVE; NATURAL-GAS HYDRATE; MONTE-CARLO; THERMODYNAMIC PROPERTIES; COMPUTER-SIMULATIONS; NEUTRON-SCATTERING; LIQUID WATER; CELL THEORY; METHANE AB We performed isothermal-isobaric molecular dynamics simulations to study the effects of host-guest asymmetries on the thermophysical and structural properties of methane and carbon dioxide sI clathrate hydrates. In particular, we analyzed the effect of the strength of the host-guest interactions in realistic molecular descriptions of the host intermolecular potentials, the effect of the type of water intermolecular potential, and the degree of cage occupancy on the resulting properties of the hydrates. Finally, we used the simulation results to interpret the limitations and implications of the main assumptions behind the original vdWP theory of clathrates and its current modifications, which are used in the modeling of hydrate phase equilibria. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, High Temp Aqueous Chem Grp, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. RP Chialvo, AA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, High Temp Aqueous Chem Grp, Oak Ridge, TN 37831 USA. RI Houssa, Michel/C-9909-2011; Cummings, Peter/B-8762-2013; OI Cummings, Peter/0000-0002-9766-2216; Chialvo, Ariel/0000-0002-6091-4563 NR 58 TC 65 Z9 67 U1 1 U2 23 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 17 PY 2002 VL 106 IS 2 BP 442 EP 451 DI 10.1021/jp012735b PG 10 WC Chemistry, Physical SC Chemistry GA 513BB UT WOS:000173357100030 ER PT J AU Werner, JH Dyer, RB Fesinmeyer, RM Andersen, NH AF Werner, JH Dyer, RB Fesinmeyer, RM Andersen, NH TI Dynamics of the primary processes of protein folding: Helix nucleation SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID COIL KINETICS; FAST EVENTS; PEPTIDE; MODEL AB We report on the folding and unfolding dynamics of a.-helix nucleation in two model helical peptides. One of the peptides studied unfolds at lower temperatures (cold denatures) in solutions of 9% hexafluoroisopropanol. Laser-induced temperature jumps were used to rapidly perturb the helix/coil equilibrium in this peptide from a predominantly unfolded to a more folded ensemble. The peptide conformation was monitored through time-resolved absorption of the amide I' band. These experiments directly probe alpha-helix nucleation, as a majority of alpha-helices formed must start from a completely random coil conformation. In another alpha-helical peptide, the unfolding and folding kinetics of specific residues were monitored through the use of isotopically (C-13=O) labeled amino acids. By selectively measuring the unfolding kinetics of the middle of the helix, one can minimize the contribution of end-fraying effects and explicitly probe the crossing of a nucleation free energy barrier in the helix to coil direction. The results reveal that alpha-helix nucleation occurs on a sub-microsecond time-scale with a substantial enthalpic barrier. C1 Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Univ Washington, Dept Chem, Seattle, WA 98195 USA. RP Dyer, RB (reprint author), Los Alamos Natl Lab, Biosci Div, Mail Stop J586, Los Alamos, NM 87545 USA. NR 21 TC 71 Z9 73 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 17 PY 2002 VL 106 IS 2 BP 487 EP 494 DI 10.1021/jp0125799 PG 8 WC Chemistry, Physical SC Chemistry GA 513BB UT WOS:000173357100035 ER PT J AU Bowles, TJ AF Bowles, TJ TI Quantum effects of gravity SO NATURE LA English DT Editorial Material C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bowles, TJ (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 1 TC 7 Z9 7 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 17 PY 2002 VL 415 IS 6869 BP 267 EP 268 DI 10.1038/415267a PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 511YC UT WOS:000173293500023 PM 11796986 ER PT J AU Lake, B Ronnow, HM Christensen, NB Aeppli, G Lefmann, K McMorrow, DF Vorderwisch, P Smeibidl, P Mangkorntong, N Sasagawa, T Nohara, M Takagi, H Mason, TE AF Lake, B Ronnow, HM Christensen, NB Aeppli, G Lefmann, K McMorrow, DF Vorderwisch, P Smeibidl, P Mangkorntong, N Sasagawa, T Nohara, M Takagi, H Mason, TE TI Antiferromagnetic order induced by an applied magnetic field in a high-temperature superconductor SO NATURE LA English DT Article ID NEUTRON-SCATTERING; SPIN; INSULATOR; STRIPES; LIQUID; OXIDES; LINES; STATE AB One view of the high-transition-temperature (high-T-c) copper oxide superconductors is that they are conventional superconductors where the pairing occurs between weakly interacting quasi-particles (corresponding to the electrons in ordinary metals), although the theory has to be pushed to its limit(1). An alternative view is that the electrons organize into collective textures (for example, charge and spin stripes) which cannot be 'mapped' onto the electrons in ordinary metals. Understanding the properties of the material would then need quantum field theories of objects such as textures and strings, rather than point-like electrons(2-6). In an external magnetic field, magnetic flux penetrates type II superconductors via vortices, each carrying one flux quantum(7). The vortices form lattices of resistive material embedded in the non-resistive superconductor, and can reveal the nature of the ground state-for example, a conventional metal or an ordered, striped phase-which would have appeared had superconductivity not intervened, and which provides the best starting point for a pairing theory. Here we report that for one high-T-c superconductor, the applied field that imposes the vortex lattice also induces 'striped' antiferromagnetic order. Ordinary quasiparticle models can account for neither the strength of the order nor the nearly field-independent antiferromagnetic transition temperature observed in our measurements. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Oxford, Clarendon Lab, Dept Condensed Matter Phys, Oxford OX1 3PU, England. CEA, MDN, SPSMS, DRFMC, F-38054 Grenoble, France. Riso Natl Lab, Mat Res Dept, DK-4000 Roskilde, Denmark. APG, Niels Bohr Inst, Orsted Lab, DK-2100 Copenhagen, Denmark. NEC Res Inst, Princeton, NJ 08540 USA. Hahn Meitner Inst Berlin GmbH, BENSC, D-14109 Berlin, Germany. Univ Tokyo, Grad Sch Frontier Sci, Dept Adv Mat Sci, Bunkyo Ku, Tokyo 1138656, Japan. Spallat Neutron Source, Expt Facil Div, Oak Ridge, TN 37830 USA. RP Lake, B (reprint author), Oak Ridge Natl Lab, POB 2008 MS 6430, Oak Ridge, TN 37831 USA. RI McMorrow, Desmond/C-2655-2008; Takagi, Hidenori/B-2935-2010; NOHARA, Minoru/B-1476-2011; Christensen, Niels/A-3947-2012; Sasagawa, Takao/E-6666-2014; Mason, Thomas/M-5809-2014; Lefmann, Kim/M-9228-2014; Ronnow, Henrik/A-4953-2009; OI McMorrow, Desmond/0000-0002-4947-7788; Christensen, Niels/0000-0001-6443-2142; Sasagawa, Takao/0000-0003-0149-6696; Mason, Thomas/0000-0003-1880-3971; Lefmann, Kim/0000-0003-4282-756X; Ronnow, Henrik/0000-0002-8832-8865; Lake, Bella/0000-0003-0034-0964 NR 26 TC 424 Z9 425 U1 7 U2 61 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 17 PY 2002 VL 415 IS 6869 BP 299 EP 302 DI 10.1038/415299a PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 511YC UT WOS:000173293500037 PM 11797002 ER PT J AU Chapelle, FH O'Neill, K Bradley, PM Methe, BA Ciufo, SA Knobel, LL Lovley, DR AF Chapelle, FH O'Neill, K Bradley, PM Methe, BA Ciufo, SA Knobel, LL Lovley, DR TI A hydrogen-based subsurface microbial community dominated by methanogens SO NATURE LA English DT Article ID BASALT AQUIFERS; ECOSYSTEMS; DEEP; DIVERSITY; BACTERIA; ENERGY; MARS AB The search for extraterrestrial life may be facilitated if ecosystems can be found on Earth that exist under conditions analogous to those present on other planets or moons. It has been proposed, on the basis of geochemical and thermodynamic considerations, that geologically derived hydrogen might support subsurface microbial communities on Mars and Europa in which methanogens form the base of the ecosystem(1-5). Here we describe a unique subsurface microbial community in which hydrogen-consuming, methane-producing Archaea far outnumber the Bacteria. More than 90% of the 16S ribosomal DNA sequences recovered from hydrothermal waters circulating through deeply buried igneous rocks in Idaho are related to hydrogen-using methanogenic microorganisms. Geochemical characterization indicates that geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. These results demonstrate that hydrogen-based methanogenic communities do occur in Earth's subsurface, providing an analogue for possible subsurface microbial ecosystems on other planets. C1 US Geol Survey, Columbia, SC 29210 USA. Univ Massachusetts, Dept Microbiol, Amherst, MA 01003 USA. US Geol Survey, Idaho Falls, ID 83402 USA. RP Chapelle, FH (reprint author), US Geol Survey, Columbia, SC 29210 USA. NR 26 TC 244 Z9 269 U1 11 U2 95 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 17 PY 2002 VL 415 IS 6869 BP 312 EP 315 DI 10.1038/415312a PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 511YC UT WOS:000173293500041 PM 11797006 ER PT J AU O'Leary, CD Bentley, MA Lenzi, SM Martinez-Pinedo, G Warner, DD Bruce, AM Cameron, JA Carpenter, MP Davids, CN Fallon, P Frankland, L Gelletly, W Janssens, RVF Joss, DT Lister, CJ Regan, PH Reiter, P Rubio, B Seweryniak, D Svensson, CE Vincent, SM Williams, SJ AF O'Leary, CD Bentley, MA Lenzi, SM Martinez-Pinedo, G Warner, DD Bruce, AM Cameron, JA Carpenter, MP Davids, CN Fallon, P Frankland, L Gelletly, W Janssens, RVF Joss, DT Lister, CJ Regan, PH Reiter, P Rubio, B Seweryniak, D Svensson, CE Vincent, SM Williams, SJ TI Isovector pairing in odd-odd N=Z Mn-50 SO PHYSICS LETTERS B LA English DT Article DE gamma rays; high spine; isospin; neutron-proton pairings; shell model ID LOW-SPIN STRUCTURE; BAND TERMINATION; MIRROR SYMMETRY; NUCLEI; STATES; SHELL; CR-49; MN-49 AB High-spin states in the odd-odd N = Z nucleus Mn-50(25) have been investigated. A sequence of states up to J(pi) = 6(+) has been assigned as the T = 1 analogue of the yrast band in Cr-50(24) for the first time. The differences in energy between levels in these bands are interpreted in terms of rotational alignments and the effect they have on the Coulomb energy of the nucleus. Comparisons with shell model calculations show that the Coulomb energy difference between the T = 1 analogue structures is an important indicator of the competition between isovector pairing modes in N = Z nuclei and their isobars. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ York, Dept Phys, York YO10 5DD, N Yorkshire, England. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Univ Keele, Dept Phys, Keele ST5 5BG, Staffs, England. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Padua, Italy. Univ Basel, Dept Phys & Astron, CH-4056 Basel, Switzerland. CLRC, Daresbury Lab, Warrington WA4 4AD, Cheshire, England. Univ Brighton, Sch Engn, Brighton BN2 4GJ, E Sussex, England. McMaster Univ, Hamilton, ON L8S 4K1, Canada. Argonne Natl Lab, Argonne, IL 60439 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England. Univ Valencia, CSIC, Inst Fis Corpuscular, E-46071 Valencia, Spain. RP Univ York, Dept Phys, York YO10 5DD, N Yorkshire, England. EM cdoll@york.ac.uk RI Lenzi, Silvia/I-6750-2012; Martinez-Pinedo, Gabriel/A-1915-2013; Rubio, Berta/M-1060-2014; Carpenter, Michael/E-4287-2015; OI Martinez-Pinedo, Gabriel/0000-0002-3825-0131; Rubio, Berta/0000-0002-9149-4151; Carpenter, Michael/0000-0002-3237-5734; Bruce, Alison/0000-0003-2871-0517 NR 18 TC 32 Z9 33 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD JAN 17 PY 2002 VL 525 IS 1-2 BP 49 EP 55 DI 10.1016/S0370-2693(01)01426-5 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 511QN UT WOS:000173277200006 ER PT J AU Dumitru, A Pisarski, RD AF Dumitru, A Pisarski, RD TI Degrees of freedom and the deconfining phase transition SO PHYSICS LETTERS B LA English DT Article ID QUARK-GLUON PLASMA; LATTICE GAUGE-THEORY; RADIATIVE ENERGY-LOSS; 3-LOOP FREE-ENERGY; FINITE-TEMPERATURE; QUANTUM CHROMODYNAMICS; PERTURBATIVE QCD; CHIRAL-SYMMETRY; DEBYE MASS; THERMODYNAMICS AB There is a sharp increase in the relative number of degrees of freedom at the deconfining phase transition. Characterizing this increase using the Polyakov Loop model, we find that for three colors, where there is a nearly second order deconfining phase transition, the medium-induced energy loss turns on rapidly above T-c. As expected, energy loss increases proportional to the relative number of degrees of freedom. In addition, however, there is a logarithmic dependence upon the screening mass, which changes markedly near the would be critical point. Thus this sensitivity to the screening mass can be used to probe non-ideal, nearly critical, behavior in the quark-gluon plasma. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Dumitru, A (reprint author), Columbia Univ, Dept Phys, New York, NY 10027 USA. NR 66 TC 77 Z9 77 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JAN 17 PY 2002 VL 525 IS 1-2 BP 95 EP 100 DI 10.1016/S0370-2693(01)01424-1 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 511QN UT WOS:000173277200012 ER PT J AU Kind, H Yan, HQ Messer, B Law, M Yang, PD AF Kind, H Yan, HQ Messer, B Law, M Yang, PD TI Nanowire ultraviolet photodetectors and optical switches SO ADVANCED MATERIALS LA English DT Article ID CARBON NANOTUBES; QUANTUM WIRES; SINGLE-WALL; JUNCTIONS; FILMS AB Highly sensitive nanowire switches have been created using ZnO nanowires. The light-induced conductivity increase, which is extremely sensitive to ultraviolet light, allows the reversibly switching of the nanowires between the "OFF" and "ON" states by an optical gating phenomenon analogous to the commonly used electrical gating. The Figure shows a field-emission SEM image of a 60 nm ZnO nanowire bridging four Au electrodes. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Dept Chem, Berkeley, CA 94720 USA. RP Yang, PD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Dept Chem, Berkeley, CA 94720 USA. NR 15 TC 1530 Z9 1564 U1 49 U2 611 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0935-9648 J9 ADV MATER JI Adv. Mater. PD JAN 16 PY 2002 VL 14 IS 2 BP 158 EP + DI 10.1002/1521-4095(20020116)14:2<158::AID-ADMA158>3.0.CO;2-W PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 518VB UT WOS:000173687600020 ER PT J AU Eckert, J Draznieks, CM Cheetham, AK AF Eckert, J Draznieks, CM Cheetham, AK TI Direct observation of host-guest hydrogen bonding in the zeolite NaY/chloroform system by neutron scattering SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID RAMAN-SPECTROSCOPY; AQUEOUS-SOLUTION; NAY ZEOLITE; MONTE-CARLO; MAS NMR; ADSORPTION; CHLOROFORM; DIFFRACTION; TRICHLOROETHYLENE; HYDROFLUOROCARBON-134 C1 Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Versailles, Inst Lavoisier, F-78035 Versailles, France. RP Cheetham, AK (reprint author), Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. NR 36 TC 14 Z9 14 U1 2 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 16 PY 2002 VL 124 IS 2 BP 170 EP 171 DI 10.1021/ja011740q PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 510QH UT WOS:000173218400001 PM 11782158 ER PT J AU Hay, BP Dixon, DA Bryan, JC Moyer, BA AF Hay, BP Dixon, DA Bryan, JC Moyer, BA TI Crystallographic evidence for oxygen acceptor directionality in oxyanion hydrogen bonds SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID RECOGNITION; ENERGY C1 Battelle Mem Inst, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Hay, BP (reprint author), Battelle Mem Inst, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RI Solominow, Sonia/A-4021-2008; Moyer, Bruce/L-2744-2016 OI Moyer, Bruce/0000-0001-7484-6277 NR 29 TC 46 Z9 46 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 16 PY 2002 VL 124 IS 2 BP 182 EP 183 DI 10.1021/ja0173775 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 510QH UT WOS:000173218400007 PM 11782164 ER PT J AU Rodriguez, JA Hanson, JC Frenkel, AI Kim, JY Perez, M AF Rodriguez, JA Hanson, JC Frenkel, AI Kim, JY Perez, M TI Experimental and theoretical studies on the reaction of H-2 with NiO: Role of O vacancies and mechanism for oxide reduction SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ELECTRONIC-STRUCTURE CALCULATIONS; ABSORPTION FINE-STRUCTURE; TOTAL-ENERGY CALCULATIONS; PLANE-WAVE; POPULATION ANALYSIS; POWDER DIFFRACTION; TIO2(110) SURFACE; METAL OXIDES; CO; ADSORPTION AB Reduction of an oxide in hydrogen is a method frequently employed in the preparation of active catalysts and electronic devices, Synchrotron-based time-resolved X-ray diffraction (XRD), X-ray absorption fine structure (NEXAFS/EXAFS), photoemission, and first-principles density-functional (DF) slab calculations were used to study the reaction of H-2 with nickel oxide. In experiments with a NiO(100) crystal and NiO powders, oxide reduction is observed at atmospheric pressures and elevated temperatures (250-350degreesC), but only after an induction period. The results of in situ time-resolved XRD and NEXAFS/EXAFS show a direct NiO-->Ni transformation without accumulation of any intermediate phase, During the induction period, surface defect sites are created that provide a high efficiency for the dissociation of H-2. A perfect NiO(100) surface, the most common face of nickel oxide, exhibits a negligible reactivity toward H-2. The presence of O vacancies leads to an increase in the adsorption energy of H-2 and substantially lowers the energy barrier associated with the cleavage of the H-H bond. At the same time, adsorbed hydrogen can induce the migration of O vacancies from the bulk to the surface of the oxide. A correlation is observed between the concentration of vacancies in the NiO lattice and the rate of oxide reduction, These results illustrate the complex role played by O vacancies in the mechanism for reduction of an oxide. The kinetic models frequently used to explain the existence of an induction time during the reduction process can be important, but a more relevant aspect is the initial production of active sites for the rapid dissociation of H-2. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Yeshiva Univ, Dept Phys, New York, NY 10016 USA. Cent Univ Venezuela, Fac Ciencias, Caracas 1020A, Venezuela. RP Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. EM rodrigez@bnl.gov RI Hanson, jonathan/E-3517-2010; Frenkel, Anatoly/D-3311-2011 OI Frenkel, Anatoly/0000-0002-5451-1207 NR 79 TC 191 Z9 195 U1 10 U2 98 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 16 PY 2002 VL 124 IS 2 BP 346 EP 354 DI 10.1021/ja0121080 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 510QH UT WOS:000173218400030 PM 11782187 ER PT J AU Francoeur, S Norman, AG Hanna, MC Mascarenhas, A Reno, JL Follstaedt, DM Lee, SR AF Francoeur, S Norman, AG Hanna, MC Mascarenhas, A Reno, JL Follstaedt, DM Lee, SR TI Optical properties of self-assembled lateral superlattices in AlInAs epitaxial layers and AlAs/InAs short-period superlattices SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article; Proceedings Paper CT Spring Meeting of the European-Materials-Research-Society CY JUN 05-08, 2001 CL STRASBOURG, FRANCE SP European Mat Res Soc DE superlattices; AlInAs epitaxial layers; AlAs/InAs short-period layers; optical polarization anisotropy ID MOLECULAR-BEAM EPITAXY; COMPOSITION MODULATION; ALLOY DECOMPOSITION; ORDERED GAINP; THIN-FILMS; POLARIZATION; SURFACE; GROWTH; STRAIN; INSTABILITIES AB Characterization of self-assembled lateral superlattices in AllnAs epitaxial layers and AlAs/InAs short-period superlattices is presented. These structures are spontaneously generated during the epitaxial growth by metal-organic chemical vapor deposition and molecular beam epitaxy. Transmission electron microscopy reveals the structural details and electro-modulated reflectance is used to characterize the energy and anisotropy of the optical transitions in the lateral superlattices. We demonstrate several properties of these self-assembled structures: (a) the band gap energy can be changed by as much as 350 meV, (b) the polarization anisotropy of the lowest energy transition exceeds 90%, (c) the superlattice axis and the direction of the optical anisotropy can be oriented along two non-equivalent directions in the plane of the substrate, and (d) the valence band splitting between heavy and light-hole transitions is significant. We discuss the difference between the samples from the two growth techniques. Finally, we theoretically model the electronic states in these lateral superlattices and we demonstrate that the difference in average InAs composition between the well and barrier can be as high as 35%. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Sch Renewable Nat Resources, Golden, CO 80401 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Francoeur, S (reprint author), Sch Renewable Nat Resources, MS 3216,1617 Cole Blvd, Golden, CO 80401 USA. RI Norman, Andrew/F-1859-2010; Francoeur, Sebastien/E-6614-2011 OI Norman, Andrew/0000-0001-6368-521X; Francoeur, Sebastien/0000-0002-6129-7026 NR 28 TC 2 Z9 2 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5107 J9 MAT SCI ENG B-SOLID JI Mater. Sci. Eng. B-Solid State Mater. Adv. Technol. PD JAN 16 PY 2002 VL 88 IS 2-3 BP 118 EP 124 DI 10.1016/S0921-5107(01)00862-5 PG 7 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 517NG UT WOS:000173616300003 ER PT J AU Knight, SMG Umezawa, N Lee, HS Gellman, SH Kay, BK AF Knight, SMG Umezawa, N Lee, HS Gellman, SH Kay, BK TI A fluorescence polarization assay for the identification of inhibitors of the p53-DM2 protein-protein interaction SO ANALYTICAL BIOCHEMISTRY LA English DT Article DE combinatorial peptides; drug discovery; in vitro; microtiter plates; peptide; phage display; phosphopeptide; SH2 domain; sre ID TUMOR-SUPPRESSOR P53; MDM2 ONCOPROTEIN; AQUEOUS-SOLUTION; BETA-PEPTIDES; EXPRESSION; BINDING; PHOSPHORYLATION; APOPTOSIS; DISCOVERY; LEUKEMIA AB Improper function of the tumor suppressor protein p53 is a contributing factor in many human cancers. In normal cells, p53 acts to arrest the cell cycle in response to DNA damage or nucleotide depletion. One mechanism of regulating the amount of p53 in the cell is through the action of the Double Minute 2 protein, DM2 (also known as MDM2), which ubiquitinates p53 and targets it for proteosomal degradation. In a number of human cancers, the DM2 gene is amplified or overexpressed, leading to inadequate levels of p53 for cell cycle arrest or apoptosis. With the goal of restoring p53 function in cancers that overexpress DM2, we are developing inhibitors of the p53-DM2 protein-protein interaction that structurally mimic the N-terminal segment of p53 that binds to DM2. To assist this effort, we have devised a fluorescence polarization assay that quantifies the interaction between the N-terminal regions of both proteins in 384-well microtiter plates. Using this assay, we have demonstrated that a peptide with a nonhydrolyzable beta-amino acid substitution binds DM2 with an affinity comparable to a p53 peptide that is composed of only alpha-amino acids. (C) 2001 Elsevier Science. C1 Argonne Natl Lab, Div Biosci, Argonne, IL 60439 USA. Univ Wisconsin, Dept Pharmacol, Madison, WI 53706 USA. Univ Wisconsin, Dept Chem, Madison, WI 53706 USA. RP Kay, BK (reprint author), Argonne Natl Lab, Div Biosci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Lee, Hee-Seung/C-1627-2011; OI Umezawa, Naoki/0000-0003-3966-2303 FU NIGMS NIH HHS [GM-56414] NR 36 TC 28 Z9 29 U1 2 U2 5 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD JAN 15 PY 2002 VL 300 IS 2 BP 230 EP 236 DI 10.1006/abio.2001.5468 PG 7 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 513GZ UT WOS:000173371000016 PM 11779115 ER PT J AU Han, JY Craighead, HG AF Han, JY Craighead, HG TI Characterization and optimization of an entropic trap for DNA separation SO ANALYTICAL CHEMISTRY LA English DT Article ID FIELD CAPILLARY-ELECTROPHORESIS; ELECTRIC-FIELDS; MOLECULES; ARRAY; FRAGMENTS AB Recently, a microfabricated entropic trap array was demonstrated to be useful in separating large (5-200 kbp) DNA molecules efficiently (within similar to30 min), by dc electrophoresis, on a microchip platform without a sieving matrix. This paper reports further development of the technique, with emphasis on optimizing separation selectivity and resolution. The interaction of DNA molecules with regularly spaced entropic barriers was modeled in order to predict the effect of changing various structural parameters. The selectivity (differential mobility) was shown to be dependent on the depth of deep and shallow channel regions, applied electric field, and number of entropic barriers. Experimental data were compared with the prediction of the model. It was expected from the model that, in the low-field (severe trapping) limit, separation resolution should depend only on the number of entropic traps. However, in reality, resolution did depend on the applied field because the relaxation of DNA is not achieved at high fields. The requirement and feasibility of megabase pair DNA separation with the entropic trap array device was discussed. C1 Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA. RP Han, JY (reprint author), Sandia Natl Labs, Biosyst Res Dept, MS 9951, Livermore, CA 94551 USA. FU NHGRI NIH HHS [HG01506] NR 19 TC 123 Z9 124 U1 0 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JAN 15 PY 2002 VL 74 IS 2 BP 394 EP 401 DI 10.1021/ac0107002 PG 8 WC Chemistry, Analytical SC Chemistry GA 511XH UT WOS:000173290500012 PM 11811414 ER PT J AU Jones, RW Meglen, RR Hames, BR McClelland, JF AF Jones, RW Meglen, RR Hames, BR McClelland, JF TI Chemical analysis of wood chips in motion using thermal-emission mid-infrared spectroscopy with projection to latent structures regression SO ANALYTICAL CHEMISTRY LA English DT Article ID TRANSFORM INFRARED SPECTROMETRY; PROCESS ANALYTICAL-CHEMISTRY; DIFFUSE-REFLECTANCE FTIR; MULTIVARIATE CHARACTERIZATION; RAPID-DETERMINATION; PULP; NIR; SAMPLES; LIGNIN; LIGNOCELLULOSE AB The opacity and random surface orientation of process streams of solids complicates the application of spectroscopy to on-line analysis of solid streams. We have used a specialized form of thermal-emission mid-infrared spectroscopy, called transient infrared spectroscopy, combined with PLS regression to analyze a moving stream of wood chips for lignin, hemicellulose, glucan, and extractives content Sixty-eight softwood samples from 6 species were analyzed using one regression, and 28 hardwood samples from 14 species were analyzed with another. Root-mean-square errors of prediction for the properties varied from 0.8 to 1.9 wt %, depending on property and wood type, with lignin and hemicellulose being the most accurately determined and glucan being the least. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Jones, RW (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. EM jonesrw@ameslab.gov NR 35 TC 9 Z9 9 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JAN 15 PY 2002 VL 74 IS 2 BP 453 EP 457 DI 10.1021/ac0106445 PG 5 WC Chemistry, Analytical SC Chemistry GA 511XH UT WOS:000173290500020 PM 11811422 ER PT J AU Szanyi, J AF Szanyi, J TI The origin of haze in CVD tin oxide thin films SO APPLIED SURFACE SCIENCE LA English DT Article DE tin oxide thin films; haze; internal defects; rugosity; polishing; AFM ID GLASS AB The origin of haze was investigated in antimony-doped tin oxide thin films, and in double-stack thin films of fluorine-doped tin oxide/antimony-doped tin oxide, both deposited by chemical vapor deposition onto soda-lime-silica float glass substrates. These transparent conductive oxide thin films are of great importance in the production of solar control architectural glazing units. Therefore, understanding the origins of haze is necessary to the development of coated, IR-reflecting glass windows with low overall haze levels. Haze measurements of as-prepared and polished samples were correlated with surface roughness and concentration of internal hole defects. Surface roughnesses were evaluated by atomic force microscopy, and characterized by estimated RMS values. In thin tin oxide films (<2000 Angstrom) internal hole defects caused haze, while in thick tin oxide films (>4000 Angstrom) surface roughness was the primary source of haze. (C) 2002 Elsevier Science B.V. All rights reserved. C1 PPG Ind Inc, Glass Technol Ctr, Pittsburgh, PA 15238 USA. RP Szanyi, J (reprint author), Pacific NW Natl Lab, POB 999,K8-93, Richland, WA 99352 USA. NR 7 TC 27 Z9 30 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD JAN 15 PY 2002 VL 185 IS 3-4 BP 161 EP 171 DI 10.1016/S0169-4332(01)00554-2 PG 11 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 517RH UT WOS:000173623300002 ER PT J AU Ma, Q Walters, DR Rosenberg, RA AF Ma, Q Walters, DR Rosenberg, RA TI Electron-induced surface chemistry on TiN in ultrahigh vacuum SO APPLIED SURFACE SCIENCE LA English DT Article DE electron-induced surface chemistry; Auger; ultrahigh vacuum; carbon deposition; carbide formation; secondary electron yield ID TEMPERATURE OXIDATION BEHAVIOR; X-RAY; FILMS; SPECTROSCOPY; NITRIDE; CARBIDE AB The property of a TiN/vacuum interface in ultrahigh vacuum (<3 x 10(-9) Torr) and under electron beam irradiation was studied using Auger electron spectroscopy. Electron-beam energies ranged from I to 9 keV. Without electron irradiation, about I monolayer (ML) of oxygen adsorbs on the TiN surface and metal oxidation occurs. The characteristic of oxygen adsorption is discussed in terms of the relationship of gas-sticking probability with coverage within the first NIL regime. Under electron irradiation, carbon accumulates on the surface, in addition to oxygen adsorption, which modifies the surface chemistry to an extent that depends on the vacuum conditions, electron current density, and electron beam energy. For high-energy electron beams, electron bombardment induces TiC formation. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Ma, Q (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RI Rosenberg, Richard/K-3442-2012 NR 27 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD JAN 15 PY 2002 VL 185 IS 3-4 BP 217 EP 225 DI 10.1016/S0169-4332(01)00784-X PG 9 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 517RH UT WOS:000173623300008 ER PT J AU Oshima, J Huang, SR Pae, C Campisi, J Schiestl, RH AF Oshima, J Huang, SR Pae, C Campisi, J Schiestl, RH TI Lack of WRN results in extensive deletion at nonhomologous joining ends SO CANCER RESEARCH LA English DT Article ID WERNER-SYNDROME PROTEIN; DNA-POLYMERASE-DELTA; FUNCTIONAL INTERACTION; RETROVIRAL VECTORS; BLOOMS-SYNDROME; GENE-TRANSFER; HELICASE; CELLS; RECOMBINATION; EXONUCLEASE AB Loss of WRN causes the genomic instability progeroid syndrome, Werner syndrome. WRN encodes a multifunctional nuclear protein with 3'-->5' exonuclease and 3'-->5' helicase activities. Linear plasmids with noncompatible ends introduced to Werner syndrome cells underwent extensive deletions at nonhomologous joining ends, particularly at the 3' protruding single-stranded end. This extensive deletion phenotype was complemented by wild-type WRN. These results suggest that WRN can out-compete other exonucleases that participate in double-strand break repair or stabilize the broken DNA end. C1 Univ Washington, Dept Pathol, Seattle, WA 98195 USA. Lawrence Berkeley Natl lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Los Angeles, Dept Pathol, Los Angeles, CA 90095 USA. RP Oshima, J (reprint author), Univ Washington, Dept Pathol, Box 357470, Seattle, WA 98195 USA. FU NCI NIH HHS [CA78088, CA77852]; NIA NIH HHS [AG11658, AG14446]; NIEHS NIH HHS [ES00299, ES09519] NR 40 TC 68 Z9 69 U1 0 U2 1 PU AMER ASSOC CANCER RESEARCH PI BIRMINGHAM PA PO BOX 11806, BIRMINGHAM, AL 35202 USA SN 0008-5472 J9 CANCER RES JI Cancer Res. PD JAN 15 PY 2002 VL 62 IS 2 BP 547 EP 551 PG 5 WC Oncology SC Oncology GA 515HE UT WOS:000173488700036 PM 11809708 ER PT J AU Fuller, CC Bargar, JR Davis, JA Piana, MJ AF Fuller, CC Bargar, JR Davis, JA Piana, MJ TI Mechanisms of uranium interactions with hydroxyapatite: Implications for groundwater remediation SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID INORGANIC CATION-EXCHANGERS; SYNTHETIC HYDROXYAPATITES; LEAD IMMOBILIZATION; AQUEOUS-SOLUTION; SORPTION; COMPLEXES; DISSOLUTION; EXAFS; HYDROXYLAPATITE; NUCLEATION AB The speciation of U(VI) sorbed to synthetic hydroxyapatite was investigated using a combination of U L-III-edge XAS, synchrotron XRD, batch uptake measurements, and SEW EDS. The mechanisms of U(VI) removal by apatite were determined in order to evaluate the feasibility of apatite-based in-situ permeable reactive barriers (PRBs). In batch U(VI) uptake experiments with synthetic hydroxyapatite (HA), near complete removal of dissolved uranium (>99.5%) to <0.05 muM was observed over a range of total U(VI) concentrations up to equimolar of the total P in the suspension. XRD and XAS analyses of U(VI)-reacted HA at sorbed concentrations less than or equal to4700 ppm U(VI) suggested that uranium(VI) phosphate, hydroxide, and carbonate solids were not present at these concentrations, Fits to EXAFS spectra indicate the presence of Ca neighbors at 3.81 Angstrom. U-Ca separation, suggesting that U(VI) adsorbs to the HA surfaces as an inner-sphere complex, Uranium(VI) phosphate solid phases were not detected in HA with 4700 ppm sorbed U(VI) by backscatter SEM or EDS, in agreement with the surface complexation process. In contrast, U(VI) speciation in samples that exceeded 7000 ppm sorbed U(VI) included a crystalline uranium(VI) phosphate solid phase, identified as chernikovite by XRD. At these higher concentrations, a secondary, uranium(VI) phosphate solid was detected by SEM-EDS, consistent with chernikovite precipitation. Autunite formation occurred at total U:P molar ratios greater than or equal to0.2. Our findings provide a basis for evaluating U(VI) sorption mechanisms by commercially available natural apatites for use in development of PRBs for groundwater U(VI) remediation. C1 US Geol Survey, Menlo Pk, CA 94025 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Fuller, CC (reprint author), US Geol Survey, 345 Middlefield Rd,MS 465, Menlo Pk, CA 94025 USA. OI Fuller, Christopher/0000-0002-2354-8074 NR 42 TC 179 Z9 184 U1 12 U2 85 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD JAN 15 PY 2002 VL 36 IS 2 BP 158 EP 165 DI 10.1021/es0108483 PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 512EP UT WOS:000173308400007 PM 11827049 ER PT J AU Xiao, CB Wesolowski, DJ Palmer, DA AF Xiao, CB Wesolowski, DJ Palmer, DA TI Formation quotients of aluminum sulfate complexes in NaCF3SO3 media at 10, 25, and 50 degrees C from potentiometric titrations using a mercury/mercurous sulfate electrode concentration cell SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID SODIUM-CHLORIDE SOLUTIONS; TEMPERATURE ACIDIC WATERS; AQUEOUS-SOLUTION; ELEVATED-TEMPERATURES; NATURAL-WATERS; SULFURIC-ACID; EQUILIBRIA; SPECIATION; DISSOCIATION; SOLUBILITY AB Mercury/mercurous sulfate electrode concentration cells (with liquid junction) are employed in this study to determine the formation constants of aluminum sulfate complexes, with the principal advantage that the change in the free sulfate concentration is measured directly without the need to know the standard potential of the electrode. Potentiometric titrations were conducted at temperatures of 10, 25, and 50 degreesC and ionic strengths of approximately 0.3, 0.5, and 1.0 molal in aqueous solutions of the inert 1:1 electrolyte sodium trifluoromethanesulfonate (NaTr). Stoichiometric molal formation quotients 01 and 02, respectively, for the reactions Al3+(aq) + SO42-(aq) reversible arrow AlSO4+(aq) and Al3+(aq) + 2SO(4)(2-)(aq) reversible arrow Al(SO4)(2-)(aq) were determined. The values of log Q(1) obtained from this work in NaTr media at ionic strengths of 0.3 and 1.0 mol(.)kg(-1) and 50 degreesC (1.72 +/- 0.08 and 1.35 +/- 0.06, respectively) are in excellent agreement with the values (1.71 +/- 0.2 and 1.32 +/- 0.1) determined in NaCl media from the recent potentiometric study conducted in the same laboratory using a hydrogen electrode concentration cell by Ridley et al. (Ridley, M. K.; Wesolowski, D. J.; Palmer, D. A.; Kettler, R. M. Geochim. Cosmochim, Acta 1999, 62, 459-472). The value of log Q(2) (2.05 +/- 0.05) in 1.0 mol(.)kg(-1) from this work is smaller than the value reported by Ridley et al, (2.6 +/- 0.5) but within the combined experimental error. Empirical isothermal equations are presented to permit calculation of the equilibrium quotients as a function of ionic strength (0-1 mol(.)kg(-1)), giving log K-1 and log K-2 values at 25 degreesC and infinite dilution of 3.84 +/- 0.12 and 5.58 +/- 0.09, respectively. The value for log K-1 obtained in this study at 25 degreesC is bracketed within experimental uncertainty by values reported by Kryzhanovskii et al. (Kryzhanovskii, M. M.; Volokhov, Y. A.; Pavlov, L. N.; Eremin, N. L; Mironov, V. E Zh. Prikl. Khim. 1971, 44, 476-479) and Nishide and Tsuchiya (Nishide, T.; Tsuchiya, R. Bull. Chem. Soc. Jpn. 1965, 38, 1398-1400), namely, 3.89 and 3.73, respectively. All other literature values for the first aluminum sulfate association constant are considerably lower than these results, which is also true for the second association constant, although there are few experimental data available for the fatter. Empirical equations are also presented for calculating values of log Q(1) and log Q(2) from 0 to 1 molal ionic strength and from 10 to 125 degreesC, spanning the range of most environmental conditions at which these reactions are important. C1 Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Wesolowski, DJ (reprint author), Oak Ridge Natl Lab, Div Chem Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 44 TC 11 Z9 11 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD JAN 15 PY 2002 VL 36 IS 2 BP 166 EP 173 DI 10.1021/es001424w PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 512EP UT WOS:000173308400008 PM 11827050 ER PT J AU Riley, WJ McKone, TE Lai, ACK Nazaroff, WW AF Riley, WJ McKone, TE Lai, ACK Nazaroff, WW TI Indoor particulate matter of outdoor origin: Importance of size-dependent removal mechanisms SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID AEROSOL DEPOSITION MEASUREMENTS; PERSONAL EXPOSURE; AIRBORNE PARTICLES; FINE PARTICLES; AIR-POLLUTION; DISTRIBUTIONS; RESUSPENSION; CLEANERS; CARBON; RATES AB Adverse human health effects have been observed to correlate with levels of outdoor particulate matter (PM), even though most human exposure to PM of outdoor origin occurs indoors. In this study, we apply a model and empirical data to explore the indoor PM levels of outdoor origin for two major building types: offices and residences. Typical ventilation rates for each building type are obtained from the literature. Published data are combined with theoretical analyses to develop representative particle penetration coefficients, deposition loss rates, and ventilation-system filter efficiencies for a broad particle size range (i.e., 0.001-10 mum). We apply archetypal outdoor number, surface area, and mass PM size distributions for both urban and rural airsheds. We also use data on mass-weighted size distributions for specific chemical constituents of PM: sulfate and elemental carbon. Predictions of the size-resolved indoor proportion of outdoor particles (IPOP) for various conditions and ambient particle distributions are then computed. The IPOP depends strongly on the ambient particle size distribution, building type and operational parameters, and PM metric. We conclude that an accurate determination of exposure to particles of ambient origin requires explicit consideration of how removal processes in buildings vary with particle size. C1 EO Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Indoor Environm Dept, Berkeley, CA 94720 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. RP Riley, WJ (reprint author), EO Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Indoor Environm Dept, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Lai, Alvin/G-8409-2011; Nazaroff, William/C-4106-2008; Riley, William/D-3345-2015 OI Lai, Alvin/0000-0002-6202-1988; Nazaroff, William/0000-0001-5645-3357; Riley, William/0000-0002-4615-2304 NR 48 TC 184 Z9 189 U1 15 U2 96 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD JAN 15 PY 2002 VL 36 IS 2 BP 200 EP 207 DI 10.1021/es010723y PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 512EP UT WOS:000173308400013 PM 11831216 ER PT J AU Vulava, VM Perry, EB Romanek, CS Seaman, JC AF Vulava, VM Perry, EB Romanek, CS Seaman, JC TI Dissolved gases as partitioning tracers for determination of hydrogeological parameters SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID NONAQUEOUS PHASE LIQUID; ATLANTIC COASTAL-PLAIN; SULFUR-HEXAFLUORIDE; SHALLOW GROUNDWATER; CHLOROFLUOROCARBONS CCL3F; FLUOROBENZOATE TRACERS; NONREACTIVE TRACERS; POROUS-MEDIA; TRAPPED GAS; WATER AB In this study, dissolved Kr and SF6 gases were used to determine various hydrogeological parameters of laboratory columns under water-saturated and partially saturated conditions as a function of the flow velocity. The dissolved gases behaved conservatively in saturated columns but were significantly retarded in unsaturated conditions as a direct function of the Henry's law constant (K-H) and the ratio of column pore spaces filled with air and water (V-g/V-w). Lower aqueous diffusion coefficients for SF6 compared to that for Kr also resulted in significant rate-limited mass transport across gas-water interface. This effect was exacerbated at higher flow velocities as was indicated by the asymmetric shape of breakthrough curves, more so in the case of SF6. A nonequilibrium advective-dispersive transport model accurately described tracer breakthrough and was used to estimate parameters such as final V-g/V-w under partially saturated conditions and partitioning rates, Internally consistent model results were obtained for both dissolved gases despite the wide range in physical properties (e.g., K-H and aqueous diffusion coefficients), suggesting that dissolved Kr and SF6 may be used in conjunction to delineate and validate aquifer characteristics simultaneously from a single pulse injection of the tracer. C1 Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Aiken, SC 29802 USA. RP Vulava, VM (reprint author), Univ Tennessee, Dept Geol Sci, 1412 Circle Dr, Knoxville, TN 37996 USA. NR 53 TC 17 Z9 17 U1 4 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD JAN 15 PY 2002 VL 36 IS 2 BP 254 EP 262 DI 10.1021/es0107024 PG 9 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 512EP UT WOS:000173308400021 PM 11827060 ER PT J AU Niemann, C Tauschwitz, A Penache, D Neff, S Knobloch, R Birkner, R Presura, R Hoffmann, DHH Yu, SS Sharp, WM AF Niemann, C Tauschwitz, A Penache, D Neff, S Knobloch, R Birkner, R Presura, R Hoffmann, DHH Yu, SS Sharp, WM TI Initiation of long, free-standing z discharges by CO2 laser gas heating SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ION-BEAM-TRANSPORT; INERTIAL CONFINEMENT FUSION; PLASMA CHANNELS; Z-PINCH AB High current discharge channels can neutralize both current and space charge of very intense ion beams. Therefore, they are considered an interesting solution for final focus and beam transport in a heavy ion beam fusion reactor. At the Gesellschaft fuer Schwerionenforschung accelerator facility, 50 cm long, free-standing discharge channels were created in a 60 cm diameter metallic chamber. Discharges with currents of 45 kA in 2 to 25 mbar ammonia (NH3) gas are initiated by a CO2 laser pulse along the channel axis before the capacitor bank is triggered. Resonant absorption of the laser, tuned to the v(2) vibration of the ammonia molecule, causes strong gas heating. Subsequent expansion and rarefaction of the gas prepare the conditions for a stable discharge to fulfill the requirements for ion beam transport. The influence of an electric prepulse on the high current discharge was investigated. This article describes the laser-gas interaction and the discharge initiation mechanism. We found that channels are magnetohydrodynamic stable up to currents of 45 kA, measured by fast shutter and streak imaging techniques. The rarefaction of the laser heated gas is studied by means of a one-dimensional Lagrangian fluid code (CYCLOPS) and is identified as the dominant initiation mechanism of the discharge. (C) 2002 American Institute of Physics. C1 Tech Univ Darmstadt, D-64289 Darmstadt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Niemann, C (reprint author), Tech Univ Darmstadt, Schlossgartenstr 9, D-64289 Darmstadt, Germany. RI Hoffmann, Dieter H.H./A-5265-2008 NR 20 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 15 PY 2002 VL 91 IS 2 BP 617 EP 623 DI 10.1063/1.1426239 PG 7 WC Physics, Applied SC Physics GA 506NG UT WOS:000172978200009 ER PT J AU Yu, ACC Lo, CCH Petford-Long, AK Jiles, DC Miyazaki, T AF Yu, ACC Lo, CCH Petford-Long, AK Jiles, DC Miyazaki, T TI Lorentz transmission electron microscopy and magnetic force microscopy characterization of NiFe/Al-oxide/Co films SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Magnetization reversal process of NiFe/Al-oxide/Co junction films was observed directly using Lorentz transmission electron microscopy (LTEM) and magnetic force microscopy (MFM). In situ magnetizing experiments performed in both LTEM and MFM were facilitated by a pair of electromagnets, which were mounted on the sample stages. A two-stage magnetization reversal process for the junction film was clearly observed in LTEM with NiFe magnetization reversed first via domain wall motion followed by Co magnetization reversal via moment rotation and domain wall motion. Reversal mechanism and domain characteristics of the NiFe and Co layers showed very distinctive features. The magnetization curve of the junction film measured using alternating gradient force magnetometry showed a nonzero slope at the antiparallel magnetization configuration region, which implies that magnetization directions of the NiFe and Co layers were not exactly antiparallel due to Co moment rotation existed in that region. After the magnetization reversal of the Co was complete, MFM images revealed some magnetic contrast, which suggests that an out-of-plane magnetization component remained in the Co layer. Such magnetic contrast disappeared at higher magnetic fields when the Co moments further rotated and aligned parallel to the applied field direction. (C) 2002 American Institute of Physics. C1 Univ Oxford, Dept Mat, Oxford OX1 3PH, England. Tohoku Univ, Grad Sch Engn, Dept Appl Phys, Sendai, Miyagi 9808579, Japan. US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Yu, ACC (reprint author), Sony Corp, Recording Media Co, 3-4-1 Sakuragi, Tagajo, Miyagi 9850842, Japan. RI Miyazaki, Terunobu/E-5068-2010; Jiles, David/H-9548-2012; Petford-Long, Amanda/P-6026-2014 OI Petford-Long, Amanda/0000-0002-3154-8090 NR 12 TC 2 Z9 2 U1 1 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 15 PY 2002 VL 91 IS 2 BP 780 EP 784 DI 10.1063/1.1427142 PG 5 WC Physics, Applied SC Physics GA 506NG UT WOS:000172978200036 ER PT J AU Wang, PX Ho, YK Yuan, XQ Kong, Q Cao, N Shao, L Sessler, AM Esarey, E Moshkovich, E Nishida, Y Yugami, N Ito, H Wang, JX Scheid, S AF Wang, PX Ho, YK Yuan, XQ Kong, Q Cao, N Shao, L Sessler, AM Esarey, E Moshkovich, E Nishida, Y Yugami, N Ito, H Wang, JX Scheid, S TI Characteristics of laser-driven electron acceleration in vacuum SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID HIGH-INTENSITY LASER; COMPTON-SCATTERING; WAKEFIELD ACCELERATION; RELATIVISTIC ENERGIES; VIOLENT ACCELERATION; PLASMAS; PULSES; FIELD; BEAM; ULTRASHORT AB The interaction of free electrons with intense laser beams in vacuum is studied using a three-dimensional test particle simulation model that solves the relativistic Newton-Lorentz equations of motion in analytically specified laser fields. Recently, a group of solutions was found for very intense laser fields that show interesting and unusual characteristics. In particular, it was found that an electron can be captured within the high-intensity laser region, rather than expelled from it, and the captured electron can be accelerated to GeV energies with acceleration gradients on the order of tens of GeV/cm. This phenomenon is termed the capture and acceleration scenario (CAS) and is studied in detail in this article. The accelerated GeV electron bunch is a macropulse, with duration equal to or less than that of the laser pulse, which is composed of many micropulses that are periodic at the laser frequency. The energy spectrum of the CAS electron bunch is presented. The dependence of the energy exchange in the CAS on various parameters, e.g., a(0) (laser intensity), w(0) (laser radius at focus), tau (laser pulse duration), b(0) (the impact parameter), and theta (i) (the injection angle with respect to the laser propagation direction), are explored in detail. A comparison with diverse theoretical models is also presented, including a classical model based on phase velocities and a quantum model based on nonlinear Compton scattering. (C) 2002 American Institute of Physics. C1 Fudan Univ, Inst Modern Phys, Shanghai 200433, Peoples R China. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Grad Sch Engn, Utsunomiya, Tochigi 3218505, Japan. Univ Giessen, Inst Theoret Phys, D-35392 Giessen, Germany. RP Ho, YK (reprint author), Fudan Univ, Inst Modern Phys, Shanghai 200433, Peoples R China. NR 49 TC 53 Z9 53 U1 2 U2 12 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 15 PY 2002 VL 91 IS 2 BP 856 EP 866 DI 10.1063/1.1423394 PG 11 WC Physics, Applied SC Physics GA 506NG UT WOS:000172978200048 ER PT J AU Salve, R Wang, JSY Doughty, C AF Salve, R Wang, JSY Doughty, C TI Liquid-release tests in unsaturated fractured welded tuffs: I. Field investigations SO JOURNAL OF HYDROLOGY LA English DT Article DE vadose zone; welded tuff; fractures; seepage ID WALLED ROCK FRACTURES; POROUS-MEDIUM; RELATIVE PERMEABILITY; PREFERENTIAL FLOW; SOLUTE TRANSPORT; WATER SEEPAGE; FLUID-FLOW; MODEL; CHALK; FRONT AB Wetting-front movement, flow-field evolution, and drainage of fracture flow paths were evaluated within the Topopah Spring welded tuff at Yucca Mountain, Nevada. Equipment and techniques were developed for in situ quantification of formation intake rates, flow velocities, seepage rates, and volumes of fracture flow paths. Localized injections of liquid into a low-permeability zone (LPZ) and a high-permeability zone (HPZ) along a borehole were detected in two boreholes below the point of injection. For the LPZ tests, water did not seep into an excavated slot that defined the lower boundary of the test bed, and the liquid-intake rate under constant-head conditions was observed to steadily decrease by two orders of magnitude. In the HPZ, liquid-intake rates under constant-head conditions were significantly higher and did not exhibit a strong systematic decline. HPZ tests were also conducted under a range of constant-flow conditions. Slot seepage rates showed intermittent responses and the percentage of injected water recovered in the slot increased as each test progressed. A maximum of 80% of the injected water was recovered during high-rate injection tests. The flow path volumes were found to increase during the course of each HPZ test. The data collected during these field tests has provided useful information for developing an understanding of liquid flow in unsaturated fractured welded tuff. It has also provided a basis for quantitative comparisons with numerical simulations of liquid-release experiments, as demonstrated in a companion paper [J. Hydrol. 256 (2002)]. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Salve, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd,MS 14-116, Berkeley, CA 94720 USA. RI Doughty, Christine/G-2389-2015 NR 31 TC 20 Z9 22 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD JAN 15 PY 2002 VL 256 IS 1-2 BP 60 EP 79 DI 10.1016/S0022-1694(01)00519-4 PG 20 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 508ZN UT WOS:000173119800005 ER PT J AU Doughty, C Salve, R Wang, JSY AF Doughty, C Salve, R Wang, JSY TI Liquid-release tests in unsaturated fractured welded tuffs: II. Numerical modeling SO JOURNAL OF HYDROLOGY LA English DT Article DE hydrogeology; vadose zone; fractures; preferential flow; Yucca Mountain; numerical models ID WALLED ROCK FRACTURES; YUCCA-MOUNTAIN; POROUS-MEDIA; THERMOHYDROLOGIC CONDITIONS; RELATIVE PERMEABILITY; CAPILLARY-PRESSURE; FLOW; TRANSPORT; WATER; CONDUCTIVITY AB We have carried out a numerical modeling study in conjunction with the in situ liquid-release experiment described in Salve et al. [J. Hydrol. 257 (2001)]. The experiment site is a highly fractured welded tuff accessed from the Exploratory Studies Facility, an underground laboratory in the unsaturated zone at Yucca Mountain, Nevada. The experiment examines the effect of the rock matrix on liquid flow and transport that occurs primarily through the fracture network. The purpose of the modeling is to aid in experimental design, predict experimental results, and study the physical processes accompanying liquid flow through unsaturated fractured welded tuff. The model uses cubic elements arranged in a regular three-dimensional grid to represent a 24 m(3) block of fractured tuff. High-permeability fracture elements located deterministically preserve the connectivity of the fracture network, which is crucial to its ability to conduct fluid. Because element thickness is much greater than fracture aperture, fracture elements are assigned properties of a fracture continuum rather than of an individual fracture. The fracture network is constructed using fracture geometry data taken from a fracture map of the walls and ceiling of the alcove adjacent to the field test site. The network is then refined using the results of air-permeability tests. Model results suggest that it may not be sufficient to conceptualize the fractured tuff as consisting of high-permeability fractures embedded in a low-permeability matrix. The need to include a secondary fracture network (with distinct characteristics from the network of larger mapped fractures) is demonstrated by comparison to the liquid flow observed in the field. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd,MS 90-1116, Berkeley, CA 94720 USA. EM cadoughty@lbl.gov RI Doughty, Christine/G-2389-2015 NR 54 TC 7 Z9 8 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 EI 1879-2707 J9 J HYDROL JI J. Hydrol. PD JAN 15 PY 2002 VL 256 IS 1-2 BP 80 EP 105 DI 10.1016/S0022-1694(01)00521-2 PG 26 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 508ZN UT WOS:000173119800006 ER PT J AU Kim, YH Kulik, SP Shih, YH AF Kim, YH Kulik, SP Shih, YH TI Quantum teleportation with a complete Bell state measurement SO JOURNAL OF MODERN OPTICS LA English DT Article ID PODOLSKY-ROSEN CHANNELS; COMMUNICATION; REALIZATION; SCHEME AB By using the quantum teleportation protocol, Alice can send an unknown quantum state (e.g. the polarization of a single photon) to Bob without ever knowing about it. This paper discusses a quantum teleportation experiment in which nonlinear interactions are used for the Bell state measurement. Since the Bell state measurement is based on nonlinear interactions, all four Bell states can be distinguished. Therefore, teleportation of a polarization state can occur with certainty, in principle. Details of the theory and the experimental set-up are discussed. C1 Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. Moscow MV Lomonosov State Univ, Dept Phys, Moscow, Russia. RP Kim, YH (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Kim, Yoonho/D-2591-2012 NR 25 TC 12 Z9 12 U1 0 U2 6 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK,, ABINGDON OX14 4RN, OXON, ENGLAND SN 0950-0340 J9 J MOD OPTIC JI J. Mod. Opt. PD JAN 15 PY 2002 VL 49 IS 1-2 SI SI BP 221 EP 236 DI 10.1080/09500340110087633 PG 16 WC Optics SC Optics GA 513NK UT WOS:000173384500017 ER PT J AU Salazar, MR Thompson, SL Laintz, KE Pack, RT AF Salazar, MR Thompson, SL Laintz, KE Pack, RT TI Degradation of a poly(ester urethane) elastomer. I. Absorption and diffusion of water in Estane (R) 5703 and related polymers SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE poly(ester urethane); water solubility; water diffusion; water clusters; thermodynamics; degradation; diffusion; polyurethanes; solution properties ID SATURATED AQUEOUS-SOLUTIONS; HUMIDITY FIXED-POINTS; VAPOR; SOLUBILITY AB In preparation for studying the hydrolytic degradation of Estane(R) 5703 and related poly(ester urethane) elastomers, the absorption (solubility) and diffusion of water in these polymers have been examined experimentally and modeled theoretically. Weight gain and loss experiments have been carried out. The amount of water absorbed per gram of sample was linear at low relative humidities (RHs) but curved upward at higher RHs. This curvature was not fit by Henry's law or the Flory-Huggins equation but was easily fit by a water-cluster model. Diffusion coefficients were determined by fitting the time dependence of the sample weights, and the diffusion appeared Fickian to within experimental uncertainty. The similarity of related polymers was used to determine the approximate temperature dependence of the absorption. (C) 2001 John Wiley & Sons, Inc. C1 Los Alamos Natl Lab, Div Theoret, Grp T 12, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div DX, Grp DX 2, Los Alamos, NM 87545 USA. RP Pack, RT (reprint author), Los Alamos Natl Lab, Div Theoret, Grp T 12, MS B268, Los Alamos, NM 87545 USA. NR 34 TC 16 Z9 16 U1 1 U2 12 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD JAN 15 PY 2002 VL 40 IS 2 BP 181 EP 191 DI 10.1002/polb.10079.abs PG 11 WC Polymer Science SC Polymer Science GA 507CV UT WOS:000173010100001 ER PT J AU Salazar, MR Pack, RT AF Salazar, MR Pack, RT TI Degradation of a poly(ester urethane) elastomer. II. Kinetic modeling of the hydrolysis of a poly(butylene adipate) SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE degradation; poly(ester urethane); hydrolysis; kinetics modeling; polyurethanes; esterification AB In preparation for studying the kinetics of the hydrolysis of Estane(R) 5703, published hydrolysis data for a similar poly(butylene adipate) (herein called 63 PBA) have been modeled. Poly(ester urethanes) are known to degrade by acid-catalyzed hydrolysis of the ester links, and the data on 63 PBA show that this degradation is reversible at low relative humidities (RHs). Previous work with these data was unable to fit them with concentration-independent rate coefficients. It is shown herein that, with the water-concentration model of the preceding article and the A(AC)2 mechanism of reversible hydrolysis/esterification, the experimental kinetic data that vary across temperature, RH, and starting molecular weight can be fit with a single set of concentration-independent rate coefficients. (C) 2001 John Wiley & Sons, Inc. C1 Los Alamos Natl Lab, Div Theoret, Grp T 12, Los Alamos, NM 87545 USA. RP Pack, RT (reprint author), Los Alamos Natl Lab, Div Theoret, Grp T 12, MS B268, Los Alamos, NM 87545 USA. NR 12 TC 10 Z9 10 U1 1 U2 5 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD JAN 15 PY 2002 VL 40 IS 2 BP 192 EP 200 DI 10.1002/polb.10080 PG 9 WC Polymer Science SC Polymer Science GA 507CV UT WOS:000173010100002 ER PT J AU Kim, J Amine, K AF Kim, J Amine, K TI A comparative study on the substitution of divalent, trivalent and tetravalent metal ions in LiNi1-xMxO2 (M = Cu2+, Al3+ and Ti4+) SO JOURNAL OF POWER SOURCES LA English DT Article DE lithium nickelate; lithium battery; electrochemistry AB Stabilized lithium nickelate is receiving increased attention as a low-cost alternative to the LiCoO2 cathode now used in lithium batteries. Layered LiNi1-xMxO2 samples (M = Cu2+, Al3+ and Ti4+, where 0.025 less than or equal to x less than or equal to 0.2) were prepared by solid state reaction at 750 degreesC under an oxygen stream and subjected to powder X-ray diffraction analysis and coin-cell tests. The Cu2+ -substituted samples showed poor structural stability and electrochemical performance, while the Al3+ - and Ti4+ -substituted samples formed highly ordered and phase-pure layered compounds. Of the three compounds tested, the LiNi1-xTixO2 electrodes exhibited the highest capacity and best electrochemical reversibility. Indeed, the LiNi0.975Ti0.025O2 electrode achieved the highest reversible capacity and energy density (900 Wh/kg) of all known layered LiNiO2 or LiCoO2 electrodes. Indications are that the structural integrity of the LiNi1-xTixO2 materials was preserved because the Ti4+ ions prevented impurity Ni2+ migration into the lithium sites. The substitution of tetravalent titanium into lithium nickelate has proved to yield promising cathode materials and further studies are needed to optimize electrode composition and processing conditions. Published by Elsevier Science B.V. C1 Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, Argonne, IL 60439 USA. RP Kim, J (reprint author), Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Amine, Khalil/K-9344-2013 NR 11 TC 52 Z9 56 U1 1 U2 21 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD JAN 15 PY 2002 VL 104 IS 1 BP 33 EP 39 DI 10.1016/S0378-7753(01)00900-4 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 516HR UT WOS:000173548300005 ER PT J AU Devi, VM Benner, DC Brown, LR Smith, MAH Rinsland, CP Sams, RL Sharpe, SW AF Devi, VM Benner, DC Brown, LR Smith, MAH Rinsland, CP Sams, RL Sharpe, SW TI Multispectrum analysis of self- and N-2-broadening, shifting and line mixing coefficients in the nu(6) band of (CH3D)-C-12 SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE methane; monodeuterated methane; infrared spectra; Fourier transform infrared (FTIR) spectroscopy; spectral lineshape ID DIODE-LASER MEASUREMENTS; AIR-BROADENED WIDTH; 6-10 MU-M; TEMPERATURES RELEVANT; INFRARED-SPECTRUM; FITTING TECHNIQUE; CM(-1); INTENSITIES; (H2O)-O-16; ABSORPTION AB A multispectrum nonlinear least-squares fitting technique has been applied to determine accurate zero-pressure line center positions, Lorentz self- and N-2-broadening coefficients and self- and N-2-induced pressure shift coefficients of transitions in the nu (6) (E) perpendicular band of (CH3D)-C-12 between 1035 and 1270 cm(-1). Seventeen high-resolution (0.002-0.006 cm(-1)) room temperature absorption spectra recorded with two Fourier transform spectrometers (FTS) were analyzed together. Self-broadening coefficients for over 700 transitions and self-shift coefficients for more than 600 transitions were determined. Measurements of nitrogen-broadening coefficients for more than 480 transitions and nitrogen pressure induced shift coefficients for nearly 430 transitions were also made. The measurements include transitions with rotational quantum numbers as high as J " = 18 and K " = 15 and several forbidden transitions. The measurements were made in all six sub-bands (P-P, (P)Q, R-P, P-R, (R)Q and R-R). The measured self-broadening coefficients vary from 0.025-0.096 cm(-1) atm(-1) at 296 K and the N2-broadening coefficients from 0.02 to 0.08 cm(-1) atm(-1) at 296 K. Self-induced-shift coefficients range from -0.014 to +0.004 cm(-1) atm(-1) while the nitrogen-induced-shift coefficients vary from -0.013 to +0.008 cm(-1) atm(-1). Very few of the measured pressure-shift coefficients were positive, and the positive shift coefficients were mostly associated with the J " = K " transitions in the (P)Q sub-bands. The off-diagonal relaxation matrix element coefficients of a number of transitions with K " = 3 doublets for both self- and N-2-broadening were also obtained. The results obtained with the two different broadening gases are compared and discussed. Comparisons with previous values from the literature are also made. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NASA, Langley Res Ctr, Hampton, VA 23691 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Benner, DC (reprint author), Coll William & Mary, Dept Phys, Box 8795, Williamsburg, VA 23187 USA. NR 25 TC 20 Z9 20 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD JAN 15 PY 2002 VL 72 IS 2 BP 139 EP 191 PG 53 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 481GC UT WOS:000171510700004 ER PT J AU Mao, GM Saboungi, ML Price, DL Armand, M Mezei, F Pouget, S AF Mao, GM Saboungi, ML Price, DL Armand, M Mezei, F Pouget, S TI alpha-relaxation in PEO-LiTFSI polymer electrolytes SO MACROMOLECULES LA English DT Article ID MOLECULAR-DYNAMICS; NEUTRON-SCATTERING; GLASS-TRANSITION AB Relaxation processes in the ns time regime in deuterated pure PEO and two different concentrations of PEO-LiTFSI electrolytes show a stretched exponential behavior identifiable with translational motions of the chain segments. The time scale of the dynamics is slowed by factors of 3 and 10 as a result of adding lithium salt at EO:Li concentrations of 7.5 and 3, respectively, presumably due to the increased rigidity of the lattice caused by inter- and intrachain cross-linking by the Li ions. At the same time the stretching parameter is reduced by 35% and 50%, respectively. Measurements of the Q dependence show that both the relaxation time and the stretching parameter have a positive correlation with S(Q). C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Montreal, Dept Chem, Montreal, PQ H3C 3J7, Canada. Hahn Meitner Inst Berlin GmbH, Berlin, Germany. Inst Laue Langevin, F-38042 Grenoble, France. RP Price, DL (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Mao, Guomin/G-3933-2010; Price, David Long/A-8468-2013; Saboungi, Marie-Louise/C-5920-2013; pouget, stephanie/H-8164-2014 OI Saboungi, Marie-Louise/0000-0002-0607-4815; NR 15 TC 22 Z9 22 U1 3 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JAN 15 PY 2002 VL 35 IS 2 BP 415 EP 419 DI 10.1021/ma010108e PG 5 WC Polymer Science SC Polymer Science GA 510WE UT WOS:000173229600016 ER PT J AU Sides, SW Grest, GS Stevens, MJK AF Sides, SW Grest, GS Stevens, MJK TI Large-scale simulation of adhesion dynamics for end-grafted polymers SO MACROMOLECULES LA English DT Article ID MOLECULAR-WEIGHT; DIBLOCK COPOLYMER; INTERFACE; FRACTURE; CHAINS; MATRICES; MELT AB The adhesion between a polymer melt and substrate is studied in the presence of chemically attached chains on the substrate surface. Extensive molecular dynamics simulations have been carried out to study the effect of temperature, tethered chain areal density (Sigma), tethered chain length (N-t), chain bending energy (k(theta)), and tensile pull velocity (v) on the adhesive failure mechanisms of pullout and/or scission of the tethered chains. We observe a crossover from pure chain pullout to chain scission as N-t is increased. Below the glass transition, the value of N-t for which this crossover begins approaches the bulk entanglement length N-e. For the values of N-t and Sigma used here, no crossover to crazing is observed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sides, SW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 31 TC 38 Z9 38 U1 2 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JAN 15 PY 2002 VL 35 IS 2 BP 566 EP 573 DI 10.1021/ma0114739 PG 8 WC Polymer Science SC Polymer Science GA 510WE UT WOS:000173229600034 ER PT J AU Tomascik-Cheeseman, L Marchetti, F Lowe, X Shamanski, FL Nath, J Pedersen, RA Wyrobek, AJ AF Tomascik-Cheeseman, L Marchetti, F Lowe, X Shamanski, FL Nath, J Pedersen, RA Wyrobek, AJ TI CENP-B is not critical for meiotic chromosome segregation in male mice SO MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS LA English DT Article DE CENP-B; aneuploidy; FISH ID CENTROMERE PROTEIN-B; INNER KINETOCHORE PLATE; NULL MICE; MAMMALIAN CENTROMERE; C GENE; LOCALIZATION; DNA; DISRUPTION; COMPLEXES; SATELLITE AB Centromere protein B (CENP-B) is a constitutive protein that binds to a highly conserved 17 bp motif located at most mammalian centromeres. To determine whether disruption of this gene affects chromosome segregation in male germ cells, we evaluated the frequencies of disomic and diploid sperm in CENP-B heterozygous and homozygous null mice using the mouse epididymal sperm aneuploidy (ni-ESA) assay, a multicolor FISH method with probes for chromosomes X, Y and 8. The specificity and sensitivity of the ni-ESA assay was demonstrated using Robertsonian (2.8) translocation heterozygotes as positive controls for sperm aneuploidy. Our results show that the frequencies of disomic and diploid sperm did not differ significantly between CENP-B heterozygous and homozygous null mice (P greater than or equal to0.5) or from 129/Swiss isogenic mice (P greater than or equal to0.5) and B6C3F1 mice (P greater than or equal to0.2). These findings indicate that CENP-B does not have an essential role during chromosome segregation in male meiosis. (C) 2002 Published by Elsevier Science B.V. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. W Virginia Univ, Biol & Genet Dev Program, Morgantown, WV 26505 USA. Univ Calif San Francisco, Dept Obstet Gynecol & Reprod Sci, Reprod Genet Unit, San Francisco, CA 94143 USA. RP Wyrobek, AJ (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808,L-448, Livermore, CA 94550 USA. FU NIEHS NIH HHS [P4ZES04705, Y01-ES-10203-00, R01 ES09117-02] NR 35 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1383-5718 J9 MUTAT RES-GEN TOX EN JI Mutat. Res. Genet. Toxicol. Environ. Mutagen. PD JAN 15 PY 2002 VL 513 IS 1-2 BP 197 EP 203 DI 10.1016/S1383-5718(01)00315-1 PG 7 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 508AL UT WOS:000173064600022 PM 11719105 ER PT J AU Gabitov, IR Lushnikov, PM AF Gabitov, IR Lushnikov, PM TI Nonlinearity management in a dispersion-managed system SO OPTICS LETTERS LA English DT Article ID FIBER; TRANSMISSION AB We propose using a nonlinear phase-shift interferometric converter (NPSIC), a new device, for lumped compensation for nonlinearity in optical fibers. The NPSIC is a nonlinear analog of the Mach-Zehnder interferometer and provides a way to control the sign of the nonlinear phase shift. We investigate a potential use of the NPSIC for compensation for nonlinearity to develop a dispersion-managed system that is closer to an ideal linear system. More importantly, the NPSIC can be used to essentially improve single-channel capacity in the nonlinear regime. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. LD Landau Theoret Phys Inst, Moscow 117334, Russia. RP Gabitov, IR (reprint author), Los Alamos Natl Lab, Div Theoret, MS-B284, Los Alamos, NM 87545 USA. RI Lushnikov, Pavel/I-2304-2013 NR 13 TC 29 Z9 29 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JAN 15 PY 2002 VL 27 IS 2 BP 113 EP 115 DI 10.1364/OL.27.000113 PG 3 WC Optics SC Optics GA 511MX UT WOS:000173268700013 PM 18007729 ER PT J AU Bradley, DK Landen, OL Bullock, AB Glendinning, SG Turner, RE AF Bradley, DK Landen, OL Bullock, AB Glendinning, SG Turner, RE TI Efficient, 1-100-keV x-ray radiography with high spatial and temporal resolution SO OPTICS LETTERS LA English DT Article ID LASER-SYSTEM; NOVA; PLASMAS AB Transient x-ray radiography using laser-plasma emission is a powerful tool for diagnosing a large variety of high-energy-density phenomena. Traditional area- and point-backlighting techniques used at inertial confinement fusion facilities such as Nova and Omega cannot be extended efficiently to the future 100-times-larger National Ignition Facility. We have developed an x-ray backlighting technique that uses a backlit pinhole as a source for point-projection radiography. This method incorporates the principal advantages of point projection over traditional area backlighting in that it requires far less backlighter energy and produces data that are free from residual backlighter plasma structure. Moreover, the use of pinholes overcomes the usual disadvantages of point projection from pin targets, namely, degradation of spatial resolution and cooling due to plasma expansion. (C) 2002 Optical Society of America. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Bradley, DK (reprint author), Lawrence Livermore Natl Lab, POB 5508, Livermore, CA 94551 USA. NR 16 TC 26 Z9 28 U1 1 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JAN 15 PY 2002 VL 27 IS 2 BP 134 EP 136 DI 10.1364/OL.27.000134 PG 3 WC Optics SC Optics GA 511MX UT WOS:000173268700020 PM 18007736 ER PT J AU Gorbarenko, SA Khusid, TA Basov, IA Oba, T Southon, JR Koizumi, I AF Gorbarenko, SA Khusid, TA Basov, IA Oba, T Southon, JR Koizumi, I TI Glacial Holocene environment of the southeastern Okhotsk Sea: evidence from geochemical and palaeontological data SO PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY LA English DT Article DE Okhotsk Sea; palaeoenvironment; palaeoproductivity; benthic foraminifera ID DEEP-OCEAN CIRCULATION; BENTHIC FORAMINIFERA; NORTHWESTERN PACIFIC; CONTINENTAL-MARGIN; LEVEL RECORD; ATLANTIC; NEOGENE; CLIMATE; WATER; RATES AB Environmental conditions and productivity changes in the southeastern Okhotsk Sea have been reconstructed for the last 20 ka using planktonic and benthic foraminiferal oxygen isotope records and calcium carbonate, organic carbon and opal content data from two sediment cores. Species variability in benthic foraminiferal and diatom assemblages provides additional palaeoceanographic evidence. AMS radiocarbon dating of the sediments and oxygen isotope stratigraphy serve as the basis for the age models of the cores for the last 20 C-14 kyr and for correlation between environmental variations in the Okhotsk Sea, and regional and global climate changes. Benthic foraminiferal assemblages in the two cores (depth 1590 and 1175 m) varied with time, so that we could recognise seven zones with different species composition. Changes in the benthic foraminiferal assemblages parallel major environmental and productivity variations. During the last glaciation, fluxes of organic matter to the sea floor showed strong seasonal variations, indicated by the presence of abundant A. weddellensis and infaunal Uvigerina spp. Benthic foraminiferal assemblages changed with warming at 12.5-11 and 10(-8) C-14 kyr BP, when productivity blooms and high organic fluxes were coeval with global meltwater pulses 1A and 1B. Younger Dryas cooling caused a decline in productivity (11-10 kyr BP) affecting the benthic faunal community. Subsequent warming triggered intensive diatom production, opal accumulation and a strong oxygen deficiency, causing significant changes in benthic fauna assemblages from 5.26-4.4 kyr BP to present time. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, VI Ilichev Pacific Oceanol Inst, Far Branch, Vladivostok 690041, Russia. Russian Acad Sci, PP Shirshov Oceanol Inst, Moscow 117218, Russia. Russian Acad Sci, Inst Lithosphere, Moscow 109180, Russia. Hokkaido Univ, Grad Sch Environm Earth Sci, Sapporo, Hokkaido 060, Japan. Lawrence Livermore Natl Lab, Ctr AMS, Livermore, CA 94551 USA. Hokkaido Univ, Div Earth & Planetary Sci, Grad Sch Sci, Sapporo, Hokkaido, Japan. RP Gorbarenko, SA (reprint author), Russian Acad Sci, VI Ilichev Pacific Oceanol Inst, Far Branch, 43 Baltiyskaya Str, Vladivostok 690041, Russia. NR 80 TC 54 Z9 59 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-0182 J9 PALAEOGEOGR PALAEOCL JI Paleogeogr. Paleoclimatol. Paleoecol. PD JAN 15 PY 2002 VL 177 IS 3-4 BP 237 EP 263 AR PII S0031-0182(01)00335-2 DI 10.1016/S0031-0182(01)00335-2 PG 27 WC Geography, Physical; Geosciences, Multidisciplinary; Paleontology SC Physical Geography; Geology; Paleontology GA 523HH UT WOS:000173947600002 ER PT J AU Cheney, CP Budde, M Lupke, G Feldman, LC Tolk, NH AF Cheney, CP Budde, M Lupke, G Feldman, LC Tolk, NH TI Vibrational dynamics of isolated hydrogen in germanium SO PHYSICAL REVIEW B LA English DT Article ID ADSORBATE-SUBSTRATE VIBRATION; CRYSTALLINE SILICON; RAMAN-SCATTERING; DENSE MEDIUM; RELAXATION; LIFETIME; MODES; EXCITATIONS; EXCHANGE; MOLECULE AB Absorption line shapes associated with the stretch mode of bond-center hydrogen (H-BC((+))) at 1794 cm(-1) and the twofold degenerate mode of hydrogen near the tetrahedral site (H(-)) at 745 cm(-1) in germanium are measured with infrared-absorption spectroscopy. The H-BC((+)) line shape measured at 10 K for the case of low hydrogen concentrations gives a lifetime between 15 and 23 ps. Similar in magnitude to the 7.8+/-0.2 ps observed for the same defect in silicon [M. Budde et al, Phys. Rev. Lett. 85, 1452 (2000)], this observation indicates that the lifetime of the bond-centered mode is largely insensitive to the phonon frequency distributions of the host material. Pure dephasing dynamics of hydrogen in germanium are studied by measuring the shape of the 1794- and 745-cm(-1) lines as a function of temperature. These measurements are analyzed using a recently formulated exchange model for vibrational dephasing. The temperature dependence of the 1794-cm(-1) line shape is attributed to thermal fluctuations in the occupation number of a pseudolocalized mode at 75+/-2 cm(-1). C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Coll William & Mary, Dept Appl Sci, Williamsburg, VA 23187 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Cheney, CP (reprint author), Univ Louisville, Dept Elect & Comp Engn, Louisville, KY 40292 USA. NR 22 TC 2 Z9 2 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 15 PY 2002 VL 65 IS 3 AR 035214 DI 10.1103/PhysRevB.65.035214 PG 9 WC Physics, Condensed Matter SC Physics GA 514NX UT WOS:000173448900059 ER PT J AU Eriksson, O Cahay, M Wills, JM AF Eriksson, O Cahay, M Wills, JM TI Negative electron affinity material: LaS on InP SO PHYSICAL REVIEW B LA English DT Article ID COLD-CATHODE AB Rare-earth monosulfides are shown to offer attractive alternatives to the commonly used cesiated surfaces to reach negative electron affinity at various III-V semiconductor surfaces. This is illustrated by theoretical calculations of metallic overlayers of LaS on a semiconducting InP substrate using first-principles techniques. The combination of these materials is demonstrated to result in a very low work function (0.8 eV). The interface between the LaS overlayer/InP substrate is shown to be quite stable, and the lattice relaxation of the surface atoms and the atoms at the interface is found to be small. C1 Uppsala Univ, Dept Phys, Uppsala, Sweden. Univ Cincinnati, Dept Elect & Comp Engn & Comp Sci, Cincinnati, OH 45221 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Uppsala Univ, Dept Phys, Box 530, Uppsala, Sweden. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 14 TC 2 Z9 2 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2002 VL 65 IS 3 AR 033304 DI 10.1103/PhysRevB.65.033304 PG 4 WC Physics, Condensed Matter SC Physics GA 514NX UT WOS:000173448900011 ER PT J AU Markos, P Soukoulis, CM AF Markos, P Soukoulis, CM TI Transmission studies of left-handed materials SO PHYSICAL REVIEW B LA English DT Article ID LOW-FREQUENCY PLASMONS; PHOTONIC CRYSTALS; REFRACTION; INDEX; LIGHT AB Left-handed materials are studied numerically using an improved version of the transfer-matrix method. The transmission, reflection, phase of reflection, and absorption are calculated and compared with experiments for both single split-ring resonators with negative permeability and left-handed materials, which have both the permittivity epsilon and permeability mu negative. Our results suggest ways of positively identifying materials that have both epsilon and mu negative, from materials that have either mu or epsilon negative. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Slovak Acad Sci, Inst Phys, Bratislava 84228, Slovakia. RP Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Soukoulis, Costas/A-5295-2008 NR 23 TC 90 Z9 90 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2002 VL 65 IS 3 AR 033401 DI 10.1103/PhysRevB.65.033401 PG 4 WC Physics, Condensed Matter SC Physics GA 514NX UT WOS:000173448900023 ER PT J AU McCluskey, MD Haller, EE Becla, P AF McCluskey, MD Haller, EE Becla, P TI Carbon acceptors and carbon-hydrogen complexes in AlSb SO PHYSICAL REVIEW B LA English DT Article ID VIBRATIONAL-MODES; ABSORPTION; PAIRS; GAAS; ALAS; GAP; SE AB Aluminum antimonide (AlSb) has potential applications as a radiation detector and as a material in high-mobility heterostructures. As-grown AlSb exhibits p-type conductivity. Using infrared absorption spectroscopy, we have observed local vibrational modes (LVM's') arising from carbon impurities in n- and p-type AlSb. The first and second harmonies of the C-12 mode have frequencies of 591.6 and 1179.2 cm(-1), respectively, at liquid-helium temperatures. A peak at 572.9 cm(-1) is tentatively identified as the C-13 LVM. Carbon-hydrogen complexes were formed by annealing p-type AlSb in hydrogen gas, yielding a C-H stretch mode at 2566.6 cm(-1). Our results indicate that during the growth of bulk AlSb, carbon contamination may be an important Source of unintentional p-type doping. C1 Washington State Univ, Dept Phys, Pullman, WA 99164 USA. Washington State Univ, Inst Shock Phys, Pullman, WA 99164 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. RP McCluskey, MD (reprint author), Washington State Univ, Dept Phys, Pullman, WA 99164 USA. RI Schaff, William/B-5839-2009 NR 22 TC 10 Z9 10 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2002 VL 65 IS 4 AR 045201 DI 10.1103/PhysRevB.65.045201 PG 4 WC Physics, Condensed Matter SC Physics GA 518BP UT WOS:000173646800034 ER PT J AU Pasternak, MP Xu, WM Rozenberg, GK Taylor, RD Hearne, GR Sterer, E AF Pasternak, MP Xu, WM Rozenberg, GK Taylor, RD Hearne, GR Sterer, E TI Pressure-induced magnetic and electronic transitions in the layered Mott insulator FeI2 SO PHYSICAL REVIEW B LA English DT Article ID DIAMOND ANVIL CELL; COLLAPSE; FIELD AB Powder x-ray diffraction, electrical resistance, and Fe-57 Mossbauer spectroscopy at pressures to at least 40 GPa in diamond anvil cells have been employed to investigate the pressure evolution of the structural, electrical-transport, and magnetic properties of the antiferromagnetic insulator FeI2. Up to 18 GPa, the volume decreases by 25%, the resistivity decreases by eight orders of magnitude, T-N increases 16-fold to 150 K, and the Fe2+ moments remain parallel to the c axis. The change in the isomer shift (IS), which is negatively proportional to the change in the s-electron density at the Fe nucleus, follows the volume reduction by continuously decreasing from 1.0 to 0.8 mm/s, the quadrupole splitting (QS) increases monotonically from 0.6 mm, peaking at 0.85 mm/s by 12 GPa, and decreases to 0.75 at 18 GPa, and the magnetic hyperfine field H-hf composed of spin and orbital terms with opposite signs increases from 8 to 12 T. At similar to18 GPa the orbital term quenches, as is evident from a Mossbauer component characterized by H-hf=32T and e(2)q(zz)Q(3 cos(2) theta-1) =0, where the moments tilt to 55degrees, and T-N increases to 260 K. At 20 GPa an isostructural first-order phase transition occurs, accompanied by a discontinuous similar to5% decrease in volume and a considerably lower QS and IS. The c axis decreases by 5% with no decrease in the a axis, suggesting a considerable contraction of the Fe-I bond lengths. The high-pressure phase (HP) is diamagnetic, as characterized by a pure quadrupole-split spectrum to the lowest temperature of 5 K. The abundance of this diamagnetic phase increases with rising pressure reaching 100% by similar to38 GPa. The HP phase is also metallic, as shown by R(P,T) data. The observation of diamagnetism, metallic behavior, and the considerable reduction in volume distances establishes that-a Mott or charge-transfer transition has occurred, resulting in the total collapse of any electron correlation. The coexistence of several phases and their respective abundances were determined from the Mossbauer data. C1 Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Witwatersrand, Dept Phys, ZA-2050 Wits, South Africa. Nucl Res Ctr Negev, IL-84190 Beer Sheva, Israel. RP Pasternak, MP (reprint author), Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. NR 22 TC 6 Z9 6 U1 1 U2 11 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 15 PY 2002 VL 65 IS 3 AR 035106 DI 10.1103/PhysRevB.65.035106 PG 6 WC Physics, Condensed Matter SC Physics GA 514NX UT WOS:000173448900037 ER PT J AU Skierbiszewski, C Perlin, P Wisniewski, P Suski, T Geisz, JF Hingerl, K Jantsch, W Mars, DE Walukiewicz, W AF Skierbiszewski, C Perlin, P Wisniewski, P Suski, T Geisz, JF Hingerl, K Jantsch, W Mars, DE Walukiewicz, W TI Band structure and optical properties of InyGa1-yAs1-xNx alloys SO PHYSICAL REVIEW B LA English DT Article ID INTERBAND CRITICAL-POINTS; NITROGEN-INDUCED INCREASE; N-V ALLOYS; TEMPERATURE-DEPENDENCE; SPECTROSCOPIC ELLIPSOMETRY; SEMICONDUCTOR ALLOYS; GAAS1-XNX ALLOYS; GAP ENERGY; GAAS; ABSORPTION AB We have carried out comprehensive studies of the nitrogen-induced modifications of the electronic structure of InyGa1-yAs1-xNx alloys. Temperature- and composition-dependent optical absorption spectra have been measured on free-standing layers of InyGa1-yAs1-xNx thin films lattice matched to GaAs with 0 less than or equal to x = 3y less than or equal to 0.025 in the photon energy range 0.8-2.5 eV. The measurements provided information on the optical transitions at the Gamma point of the Brillouin zone. Spectroscopic ellipsometry measurements performed in a wide photon energy range 1.5-5.5 eV have been used to determine the energy dependence of the dielectric function as well as energies of E-1, E-0', and E-2 critical point transitions. Measurements of the plasma edge frequency for samples with different electron concentrations have been used to determine the dispersion relation for the lowest conduction band. The results show a large effect of nitrogen on the optical spectra and on the dispersion relations for the conduction band states close to the Gamma point. They can be consistently explained in terms of the recently proposed band anticrossing model. On the other hand, the observed small effect of N on the transition energies at the high-energy critical points can be well understood within a virtual crystal approximation. The insensitivity of the high-energy critical point transitions to the N content is in disagreement with the theoretical calculations predicting a large effect of N incorporation on the energies of X and L conduction band minima. C1 Polish Acad Sci, High Pressure Res Ctr, UNIPRESS, PL-01142 Warsaw, Poland. Natl Renewable Energy Lab, Golden, CO 80401 USA. Profactor GmbH, A-4400 Steyr, Austria. Johannes Kepler Univ Linz, Inst Halbleiter & Festkoerperphys, A-4040 Linz, Austria. Agilent Labs, Palo Alto, CA 94304 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Polish Acad Sci, High Pressure Res Ctr, UNIPRESS, Sokolowska 29, PL-01142 Warsaw, Poland. NR 56 TC 17 Z9 17 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2002 VL 65 IS 3 AR 035207 DI 10.1103/PhysRevB.65.035207 PG 10 WC Physics, Condensed Matter SC Physics GA 514NX UT WOS:000173448900052 ER PT J AU Soukoulis, CM Jiang, XY Xu, JY Cao, H AF Soukoulis, CM Jiang, XY Xu, JY Cao, H TI Dynamic response and relaxation oscillations in random lasers SO PHYSICAL REVIEW B LA English DT Article ID STRONGLY SCATTERING MEDIA; STIMULATED-EMISSION; GAIN MEDIA; LIGHT; GENERATION AB We experimentally investigate the dynamic response of random lasers using picosecond optical pumping. It is found that the turn-on time of a random laser is less than 100 ps. Above the lasing threshold, the emission pulse is shortened dramatically. The dynamics of each individual lasing mode is different. Lasing starts and gets to a maximum value at different times. In addition, lasing in different modes lasts for different periods of time, and the frequency of some lasing modes also shifts with time. Relaxation oscillations of lasing modes are observed for a random laser. The theoretical simulations based on the semiclassical laser theory and finite different time domain reproduce most of the experimental observations and provide an understanding of the dynamic response of a random laser. C1 Iowa State Univ Sci & Technol, Ames Lab, US DOE, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. RP Soukoulis, CM (reprint author), Iowa State Univ Sci & Technol, Ames Lab, US DOE, Ames, IA 50011 USA. RI Cao, Hui/F-4815-2012; Soukoulis, Costas/A-5295-2008 NR 20 TC 73 Z9 77 U1 1 U2 12 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 15 PY 2002 VL 65 IS 4 AR 041103 DI 10.1103/PhysRevB.65.041103 PG 4 WC Physics, Condensed Matter SC Physics GA 518BP UT WOS:000173646800003 ER PT J AU Xu, S Mikhailovsky, AA Hollingsworth, JA Klimov, VI AF Xu, S Mikhailovsky, AA Hollingsworth, JA Klimov, VI TI Hole intraband relaxation in strongly confined quantum dots: Revisiting the "phonon bottleneck" problem SO PHYSICAL REVIEW B LA English DT Article ID ENERGY-RELAXATION; SEMICONDUCTOR NANOCRYSTALS; ELECTRON; CDSE; LUMINESCENCE; SPECTROSCOPY; ABSORPTION; ASSIGNMENT; MECHANISM; DYNAMICS AB We study hole intraband relaxation in strongly confined CdSe quantum dots. We observe a dramatic reduction in the hole energy-loss rate in the final stage of hole relaxation at the bottom of the valence band. This reduction occurs because of a significantly increased inter-level spacing near the band edge, and, in particular, because of a large energy gap separating the lowest ("emitting") hole states from a dense quasi-continuum of higher lying states. A slowed population buildup of the lowest hole state indicates that the "phonon bottleneck," which is bypassed in the conduction band due to Auger-type electron-hole interactions, still plays a significant role in hole relaxation. C1 Los Alamos Natl Lab, Div Chem, PCS, Los Alamos, NM 87545 USA. RP Klimov, VI (reprint author), Los Alamos Natl Lab, Div Chem, PCS, MS-J585, Los Alamos, NM 87545 USA. NR 24 TC 65 Z9 65 U1 2 U2 16 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 15 PY 2002 VL 65 IS 4 AR 045319 DI 10.1103/PhysRevB.65.045319 PG 5 WC Physics, Condensed Matter SC Physics GA 518BP UT WOS:000173646800061 ER PT J AU Zapol, P Sternberg, M Curtiss, LA Frauenheim, T Gruen, DM AF Zapol, P Sternberg, M Curtiss, LA Frauenheim, T Gruen, DM TI Tight-binding molecular-dynamics simulation of impurities in ultrananocrystalline diamond grain boundaries SO PHYSICAL REVIEW B LA English DT Article ID NANOCRYSTALLINE DIAMOND; AMORPHOUS-CARBON; ATOMIC-STRUCTURE; CVD DIAMOND; DEFECTS; ENERGY; NITROGEN; DICARBON; FILMS; ENERGETICS AB Ultrananocrystalline diamond (UNCD) films grown from hydrogen-poor plasmas have grain sizes of 3-10 nm, resulting in a large number of grain boundaries. We report on density-functional-based tight-binding molecular-dynamics calculations of high-energy high-angle twist (100) grain boundaries in diamond as a model for the UNCD grain boundaries. About one-half of the carbons in the grain boundary are threefold coordinated and are responsible for states introduced into the band gap. Simulations were also performed for N, Si, and H impurities in (100) twist grain boundaries where substitution energies, optimized geometries, and electronic structures were calculated. Substitution energies were found to be substantially lower for the grain boundaries compared to the bulk diamond crystal. Nitrogen increases the number of threefold-coordinated carbons while hydrogen saturates dangling bonds. The electronic structure of UNCD is characterized by a large number of states in the band gap attributed to the bonding disorder and impurities in the grain boundaries. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Univ Paderborn, D-33098 Paderborn, Germany. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Zapol, P (reprint author), Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RI Zapol, Peter/G-1810-2012; Frauenheim, Thomas/C-5653-2015 OI Zapol, Peter/0000-0003-0570-9169; Frauenheim, Thomas/0000-0002-3073-0616 NR 34 TC 64 Z9 65 U1 1 U2 19 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2002 VL 65 IS 4 AR 045403 DI 10.1103/PhysRevB.65.045403 PG 11 WC Physics, Condensed Matter SC Physics GA 518BP UT WOS:000173646800070 ER PT J AU Anninos, P Rothman, T AF Anninos, P Rothman, T TI Instability of extremal relativistic charged spheres SO PHYSICAL REVIEW D LA English DT Article ID PARTICLE-EMISSION RATES; BLACK-HOLE MECHANICS; 3RD LAW; MASSLESS PARTICLES; NONTHERMAL NATURE; ENTROPY; SHELLS AB With the question "Can relativistic charged spheres form extremal black hole?" in mind, we investigate the properties of such spheres from a classical point of view. The investigation is carried out numerically by integrating the Oppenheimer-Volkov equation for relativistic charged fluid spheres and finding interior Reissner-Nordstrom solutions for these objects. We consider both constant density and adiabatic equations of state, as well as several possible charge distributions, and examine stability by both a normal mode and an energy analysis. In all cases, the stability limit for these spheres lies between the extremal (Q = M) limit and the black hole limit (R = R+). That is, we find that charged sphere, undergo gravitational collapse before they reach Q = M, suggesting that extremal Reissner-Nordstrom black holes produced by collapse are ruled out. A general proof of this statement would support a strong form of the cosmic censorship hypothesis, excluding not only stable naked singularities, but stable extremal black holes. The numerical results also indicate that although the interior mass-energy m(R) obeys the usual m/R < 4/9 stability limit for the Schwarzschild interior solution, the gravitational mass M does not. Indeed, the stability limit approaches R+ as Q --> M. In the Appendix we also argue that Hawking radiation will not lead to an extremal Reissner-Nordstrom black hole. All our results are consistent with the third law of black hole dynamics, as currently understood. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Bryn Mawr Coll, Dept Phys, Bryn Mawr, PA 19010 USA. RP Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM anninos1@llnl.gov; trothman@brynmawr.edu NR 22 TC 6 Z9 6 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 15 PY 2002 VL 65 IS 2 AR 024003 DI 10.1103/PhysRevD.65.024003 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 513WC UT WOS:000173402500039 ER PT J AU Arkani-Hamed, N Dimopoulos, S Dvali, G March-Russell, J AF Arkani-Hamed, N Dimopoulos, S Dvali, G March-Russell, J TI Neutrino masses from large extra dimensions SO PHYSICAL REVIEW D LA English DT Article ID SCALE QUANTUM-GRAVITY; SUBMILLIMETER DIMENSIONS; 3-BRANE UNIVERSE; TEV; UNIFICATION; MILLIMETER; HIERARCHY AB Recently it was proposed that the standard model (SM) degrees of freedom reside on a (3 + 1) -dimensional wall or "3-brane" embedded in a higher-dimensional spacetime. Furthermore, in this picture it is possible for the fundamental Planck mass M-* to be as small as the weak, scale M(*)similar or equal toO(TeV) and the observed weakness of gravity at long distances is due the existence of new submillimeter spatial dimensions, We show that in this picture it is natural to expect neutrino masses to occur in the 10(-1)-10(-4) eV range, despite the lack of any fundamental scale higher than M-*. Such suppressed neutrino masses are not the result of a seesaw, but have intrinsically higher-dimensional explanations. We explore two possibilities. The first mechanism identifies any massless bulk fermions as right-handed neutrinos. These give naturally small Dirac masses for the same reason that gravity is weak at long distances in this framework. The second mechanism takes advantage of the large infrared desert: the space in the extra dimensions. Here, small Majorana neutrino masses are generated by a breaking lepton number on distant branes. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. NYU, Dept Phys, New York, NY 10003 USA. ICTP, Trieste, Italy. CERN, Div Theory, CH-1211 Geneva 23, Switzerland. RP Arkani-Hamed, N (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 29 TC 246 Z9 246 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 15 PY 2002 VL 65 IS 2 AR 024032 DI 10.1103/PhysRevD.65.024032 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 513WC UT WOS:000173402500068 ER PT J AU Bettencourt, LMA Pao, K Sanderson, JG AF Bettencourt, LMA Pao, K Sanderson, JG TI Dynamical behavior of spatially inhomogeneous relativistic lambda phi(4) quantum field theory in the Hartree approximation SO PHYSICAL REVIEW D LA English DT Article ID LARGE-N; FINITE-TEMPERATURE; NONEQUILIBRIUM DYNAMICS; PHASE-TRANSITION; EARLY UNIVERSE; MEAN-FIELD; EVOLUTION; EQUILIBRIUM; RENORMALIZATION; DISSIPATION AB We study the dynamics of a spatially inhomogeneous quantum lambda phi(4) field theory in 1 + 1 dimensions in the Hartree approximation. In particular, we investigate the long-time behavior of this approximation in a variety of controlled situations, both at zero and finite temperature. The observed behavior is much richer than that in the spatially homogeneous case and, unlike the latter, shows some universality at long times. Nevertheless, we show that, within a family of Gaussian spatial profiles for the mean field, the evolution fails to thermalize in a quantum canonical sense, as expected from analogous results in closely related (mean field) transport theory. We argue that this dynamical approximation is best suited as a means to study the short-time decay of spatially inhomogeneous fields and in the dynamics of coherent quasiclassical inhomogeneous configurations (e.g, topological defects) in a background of dynamical self-consistent quantum fluctuations. C1 MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Comp & Computat Sci Div, Los Alamos, NM 87545 USA. RP Bettencourt, LMA (reprint author), MIT, Ctr Theoret Phys, Bldg 6-308,77 Massachusetts Ave, Cambridge, MA 02139 USA. NR 39 TC 20 Z9 20 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 15 PY 2002 VL 65 IS 2 AR 025015 DI 10.1103/PhysRevD.65.025015 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 513WC UT WOS:000173402500084 ER PT J AU Stompor, R Balbi, A Borrill, JD Ferreira, PG Hanany, S Jaffe, AH Lee, AT Oh, S Rabii, B Richards, PL Smoot, GF Winant, CD Wu, JHP AF Stompor, R Balbi, A Borrill, JD Ferreira, PG Hanany, S Jaffe, AH Lee, AT Oh, S Rabii, B Richards, PL Smoot, GF Winant, CD Wu, JHP TI Making maps of the cosmic microwave background: The MAXIMA example SO PHYSICAL REVIEW D LA English DT Article ID POWER SPECTRUM; SKY MAPS; LOSING INFORMATION AB This work describes cosmic microwave background (CMB) data analysis algorithms and their implementations, developed to produce a pixelized map of the sky and a corresponding pixel-pixel noise correlation matrix from time ordered data for a CMB mapping experiment. We discuss in turn algorithms for estimating noise properties from the time ordered data, techniques for manipulating the time ordered data, and a number of variants of the maximum likelihood map-making procedure. We pay particular attention to issues pertinent to real CMB data, and present ways of incorporating them within the framework of maximum likelihood map making. Making a map of the sky is shown to be not only an intermediate step rendering an image of the sky, but also an important diagnostic stage, when tests for and/or removal of systematic effects can efficiently be performed. The case under study is the MAXEMA-I data set. However, the methods discussed are expected to be applicable to the analysis of other current and forthcoming CMB experiments. C1 Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Copernicus Astron Ctr, Warsaw, Poland. Univ Roma Tor Vergata, Dipartimento Fis, I-00173 Rome, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. Univ Oxford, Oxford OX1 3RH, England. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Stompor, R (reprint author), Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. RI Jaffe, Andrew/D-3526-2009 NR 37 TC 32 Z9 32 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 15 PY 2002 VL 65 IS 2 AR 022003 DI 10.1103/PhysRevD.65.022003 PG 25 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 513WC UT WOS:000173402500008 ER PT J AU Szczepaniak, AP Swanson, ES AF Szczepaniak, AP Swanson, ES TI Coulomb gauge QCD, confinement, and the constituent representation SO PHYSICAL REVIEW D LA English DT Article ID QUANTUM-CHROMODYNAMIC VACUUM; CHIRAL SYMMETRY-BREAKING; QUARK-MODEL; COLOR CONFINEMENT; CONDENSED VACUUM; STRONG DECAYS; RENORMALIZATION; APPROXIMATION; QUANTIZATION; RESONANCES AB Quark confinement and the genesis of the constituent quark model are examined in nonperturbative QCD in Coulomb gauge. We employ a self-consistent method to construct a quasiparticle basis and to determine the quasiparticle interaction. The results agree remarkably well with lattice computations. They also illustrate the mechanism by which confinement and constituent quarks emerge, provide support for the Gribov-Zwanziger confinement scenario, clarify several perplexing issues in the constituent quark model, and permit the construction of an improved model of low energy QCD. C1 Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Indiana Univ, Ctr Nucl Theory, Bloomington, IN 47405 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. NR 50 TC 91 Z9 91 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 15 PY 2002 VL 65 IS 2 AR 025012 DI 10.1103/PhysRevD.65.025012 PG 23 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 513WC UT WOS:000173402500081 ER PT J AU Amberger, HD Jank, S Reddmann, H Edelstein, NM AF Amberger, HD Jank, S Reddmann, H Edelstein, NM TI Electron structure of highly symmetric compounds of f-elements. Part 33: First experimental derivation of crystal field parameters of a trigonal-bipyramidal lanthanide(III) complex: Pr[N(SiMe3)(2)](3)(CNR)(2) (R = Bu-t, C6H11) SO SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY LA German DT Article DE praseodymium(III); trigonal bipyramidal coordination; optical and magnetic circular dichroism spectra crystal field analysis; paramagnetic susceptibility ID ORGANOMETALLIC COMPLEXES; SPLITTING PATTERN; ETA(5)-CYCLOPENTADIENYL LIGAND; SIMULATION; TRIS(BIS(TRIMETHYLSILYL)AMIDO)NEODYMIUM(III); STRENGTH; IONS AB The absorption und magnetic circular dichroism spectra of the dissolved trigonal-bipyramidal complex Pr[N(SiMe3)(2)](3)((CNBu)-Bu-t)(2) (1) as well as the luminescence and absorption spectra of both solid 1 and solid Pr[N(SiMe3)(2)](3)(CNC6H11)(2) (2) (pellets, unoriented single crystals) were measured at ambient and low temperatures. Because of the violation of the selection rules for D-3h symmetry by both Compounds a reliable crystal field(CF) splitting pattern for the ground manifold H-3(4), but only a plausible for the f(2) configuration could be derived on the basis of these measurements. The latter could be simulated with a reduced r.m.s. deviation or 32.6 cm(-1) for 29 assignments by fitting the free parameters of a phenomenological Hamiltonian. The adequacy of the calculated wavefunctions of this fit in the low energy range is proved by the excellent agreement of calculated and experimental, eff temperature dependence of mu (2)(cff) for compound 1. The CF parameters of this fit are considered as a "master set" of CIF parameters for future CF analyses of the electronic structures of trigonal bipyramidally coordinated lanthanide(III) systems. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Hamburg, Inst Anorgan & Angew Chem, D-20146 Hamburg, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Amberger, HD (reprint author), Univ Hamburg, Inst Anorgan & Angew Chem, Martin Luther King Pl 6, D-20146 Hamburg, Germany. NR 42 TC 8 Z9 8 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1386-1425 J9 SPECTROCHIM ACTA A JI Spectroc. Acta Pt. A-Molec. Biomolec. Spectr. PD JAN 15 PY 2002 VL 58 IS 2 BP 379 EP 396 DI 10.1016/S1386-1425(01)00547-9 PG 18 WC Spectroscopy SC Spectroscopy GA 506JF UT WOS:000172965900018 PM 11811164 ER PT J AU Francoeur, S Hanna, MC Norman, AG Mascarenhas, A AF Francoeur, S Hanna, MC Norman, AG Mascarenhas, A TI Observation of large optical anisotropy and valence band splitting in AlInAs self-assembled lateral quantum wells SO APPLIED PHYSICS LETTERS LA English DT Article ID SHORT-PERIOD SUPERLATTICES; COMPOSITION MODULATION; ORDERED GAINP; THIN-FILMS; GROWTH AB Self-assembled lateral quantum wells in alloys of AlInAs, epitaxially deposited by metal-organic chemical vapor deposition on InP, are studied by transmission electron microscopy, modulation spectroscopy, and photoluminescence. Under particular growth conditions, the growth of a homogeneous layer results in the spontaneous self-assembly of a sequence of quantum wells with quantization axes oriented along the [110] direction. With respect to a homogeneous alloy of similar average composition, the band gap reduction observed is as large as 360 meV. A polarization anisotropy exceeding 90% is observed for the lowest energy transition and a large valence band splitting of 139 meV separates the heavy- and light-hole-like valence bands. (C) 2002 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Francoeur, S (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Norman, Andrew/F-1859-2010; Francoeur, Sebastien/E-6614-2011 OI Norman, Andrew/0000-0001-6368-521X; Francoeur, Sebastien/0000-0002-6129-7026 NR 16 TC 16 Z9 16 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 14 PY 2002 VL 80 IS 2 BP 243 EP 245 DI 10.1063/1.1432754 PG 3 WC Physics, Applied SC Physics GA 509NL UT WOS:000173153800027 ER PT J AU Look, DC Lu, H Schaff, WJ Jasinski, J Liliental-Weber, Z AF Look, DC Lu, H Schaff, WJ Jasinski, J Liliental-Weber, Z TI Donor and acceptor concentrations in degenerate InN SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; GROWTH STOICHIOMETRY; GAN; DISLOCATION; MOBILITY AB A formalism is presented to determine donor (N-D) and acceptor (N-A) concentrations in wurtzitic InN characterized by degenerate carrier concentration (n) and mobility (mu). The theory includes scattering not only by charged point defects and impurities, but also by charged threading dislocations, of concentration N-dis. For a 0.45-mum-thick InN layer grown on Al2O3 by molecular beam epitaxy, having N-dis=5x10(10) cm(-2), determined by transmission electron microscopy, n(20 K)=3.5x10(18) cm(-3) and mu(20 K)=1055 cm(2)/V s, determined by Hall effect measurements, the fitted values are N-D=4.7x10(18) cm(-3) and N-A=1.2x10(18) cm(-3). The identities of the donors and acceptors are not known, although a comparison of N-D with analytical data, and also with calculations of defect formation energies, suggests that a potential candidate for the dominant donor is H. (C) 2002 American Institute of Physics. C1 Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Cornell Univ, Dept Elect & Comp Engn, Ithaca, NY 14853 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. RP Look, DC (reprint author), Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. EM david.look@wpafb.af.mil RI Liliental-Weber, Zuzanna/H-8006-2012 NR 15 TC 120 Z9 121 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 14 PY 2002 VL 80 IS 2 BP 258 EP 260 DI 10.1063/1.1432742 PG 3 WC Physics, Applied SC Physics GA 509NL UT WOS:000173153800032 ER PT J AU Habermehl, S Carmignani, C AF Habermehl, S Carmignani, C TI Correlation of charge transport to local atomic strain in Si-rich silicon nitride thin films SO APPLIED PHYSICS LETTERS LA English DT Article ID LOW-STRESS AB Charge transport in Si-rich silicon nitride thin films is investigated. Over a composition range from Si3N4 to SiN0.54 the field dependent current density is observed to increase by as much as seven orders of magnitude, the residual Si-N bond strain decreases from 0.006 to -0.0026 and the Poole-Frenkel barrier height, Phi(B), decreases from 1.08 to 0.55 eV. A direct correlation between Phi(B) and the local atomic strain is observed. It is concluded that reductions in Phi(B) are a manifestation of compositionally induced strain relief at the molecular level. Reductions in Phi(B) result in increased Poole-Frenkel emission rates and consequently higher conductivities in Si-rich films. (C) 2002 American Institute of Physics. C1 Sandia Natl Labs, Microelect Dev Lab, Albuquerque, NM 87185 USA. RP Habermehl, S (reprint author), Sandia Natl Labs, Microelect Dev Lab, POB 5800, Albuquerque, NM 87185 USA. NR 15 TC 21 Z9 21 U1 2 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 14 PY 2002 VL 80 IS 2 BP 261 EP 263 DI 10.1063/1.1433167 PG 3 WC Physics, Applied SC Physics GA 509NL UT WOS:000173153800033 ER PT J AU Han, WQ Zettl, A AF Han, WQ Zettl, A TI Pyrolysis approach to the synthesis of gallium nitride nanorods SO APPLIED PHYSICS LETTERS LA English DT Article ID CRYSTAL GAN NANOWIRES; GROWTH; ATMOSPHERE; NANOTUBES; NH3 AB Herein we describe a pyrolysis route to the synthesis of gallium nitride (GaN) nanorods. GaN nanorods have been grown by the pyrolysis of gallium dimethylamide and ferrocene under an ammonia atmosphere. High-resolution transmission electron microscopy and energy dispersive x-ray spectrometer show that they are GaN single crystals, the sizes of which vary from 3 to 30 mum in length and 15 to 70 nm in diameter. Iron acts as an important catalyst for the GaN nanorod growth. (C) 2002 American Institute of Physics. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Zettl, A (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Han, WQ/E-2818-2013; Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 19 TC 101 Z9 109 U1 1 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 14 PY 2002 VL 80 IS 2 BP 303 EP 305 DI 10.1063/1.1431401 PG 3 WC Physics, Applied SC Physics GA 509NL UT WOS:000173153800047 ER PT J AU Campbell, J Mercier, HPA Franke, H Santry, DP Dixon, DA Schrobilgen, GJ AF Campbell, J Mercier, HPA Franke, H Santry, DP Dixon, DA Schrobilgen, GJ TI Syntheses, crystal structures, and density functional theory calculations of the closo-[1-M(CO)(3)(eta(4)-E-9)](4-) (E = Sn, Pb; M = Mo, W) cluster anions and solution NMR spectroscopic characterization of [1-M(CO)(3)(eta(4)-Sn-9)](4-)(M = Cr, Mo, W) SO INORGANIC CHEMISTRY LA English DT Article ID MAIN-GROUP ELEMENTS; MULTINUCLEAR MAGNETIC-RESONANCE; ELECTRON PAIR APPROACH; ZINTL ANIONS; BOND ORDERS; MOLECULAR GEOMETRIES; CHEMICAL-SHIFTS; METAL CLUSTERS; RAMAN-SPECTRA; SCF THEORY C1 McMaster Univ, Dept Chem, Hamilton, ON L8S 4M1, Canada. Snowbird Software Inc, Hamilton, ON L8S 3A1, Canada. Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP McMaster Univ, Dept Chem, 1280 Main St W, Hamilton, ON L8S 4M1, Canada. EM SCHROBIL@MCMASTER.CA NR 91 TC 72 Z9 72 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 EI 1520-510X J9 INORG CHEM JI Inorg. Chem. PD JAN 14 PY 2002 VL 41 IS 1 BP 86 EP 107 DI 10.1021/ic010695k PG 22 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 513CC UT WOS:000173359500013 PM 11782147 ER PT J AU Arndt, D Savage, MJ AF Arndt, D Savage, MJ TI Chiral corrections to matrix elements of twist-2 operators SO NUCLEAR PHYSICS A LA English DT Review ID BARYON MAGNETIC-MOMENTS; EFFECTIVE-FIELD THEORY; PERTURBATION-THEORY ANALYSIS; SU(3) SYMMETRY-BREAKING; VECTOR FORM-FACTORS; ISGUR-WISE FUNCTION; HEAVY-QUARK; ELECTROMAGNETIC POLARIZABILITIES; GENERALIZED POLARIZABILITIES; NUCLEAR-FORCES AB We compute the leading nonanalytic contributions of the form m(q) log m(q) to matrix elements of twist-2 operators in the nucleon and pion using effective field theory. Previously omitted one-loop contributions that are related to tree-level matrix elements by chiral symmetry are included. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Savage, MJ (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. NR 102 TC 79 Z9 79 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 14 PY 2002 VL 697 IS 1-2 BP 429 EP 439 DI 10.1016/S0375-9474(01)01223-4 PG 11 WC Physics, Nuclear SC Physics GA 501DQ UT WOS:000172667900021 ER PT J AU Jeon, S Koch, V Redlich, K Wang, XN AF Jeon, S Koch, V Redlich, K Wang, XN TI Fluctuations of rare particles as a measure of chemical equilibration SO NUCLEAR PHYSICS A LA English DT Article ID HEAVY-ION COLLISIONS; PLUS PB COLLISIONS; MODEL AB We calculate the time evolution of fluctuations for rare particles such as. e.g., kaons in 1 A GeV or charmed particles in 200 A GeV heavy-ion collisions. We find that these fluctuations are a very sensitive probe of the degree of chemical equilibration reached in these collisions. Furthermore, measuring the second factorial moment the size of the initial population can be determined. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Wroclaw, Inst Theoret Phys, PL-50204 Wroclaw, Poland. GSI Darmstadt, D-64291 Darmstadt, Germany. McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. Brookhaven Natl Lab, RIKEN, Res Ctr, Upton, NY 11973 USA. RP Koch, V (reprint author), Lawrence Berkeley Natl Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. OI Wang, Xin-Nian/0000-0002-9734-9967 NR 25 TC 25 Z9 25 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 14 PY 2002 VL 697 IS 1-2 BP 546 EP 562 DI 10.1016/S0375-9474(01)01228-3 PG 17 WC Physics, Nuclear SC Physics GA 501DQ UT WOS:000172667900026 ER PT J AU Bedaque, PF AF Bedaque, PF TI Color superconductivity in asymmetric matter SO NUCLEAR PHYSICS A LA English DT Article ID FINITE BARYON DENSITY; QUARK MATTER; QCD; TEMPERATURE; MODEL AB The influence on color superconductivity of the presence of unequal chemical potentials for different quark flavors is analyzed. It is found in a mean-field approximation that there is a first order transition as this asymmetry grows. This transition proceeds through the formation of bubbles of low density, flavor asymmetric normal phase inside a high density, superconducting phase that has a gap larger than the one found in the symmetric case. For small fixed asymmetries the system is normal at low densities and superconducting only above some critical density. For larger asymmetries the system stays in the mixed state for arbitrarily high densities. (C) 2002 Elsevier Science B.V.. All fights reserved. C1 Univ Washington, Inst Nucl Theory, Seattle, WA 98195 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Univ Washington, Inst Nucl Theory, Seattle, WA 98195 USA. EM bedaque@phys.washington.edu NR 30 TC 50 Z9 50 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 14 PY 2002 VL 697 IS 1-2 BP 569 EP 577 DI 10.1016/S0375-9474(01)01234-9 PG 9 WC Physics, Nuclear SC Physics GA 501DQ UT WOS:000172667900028 ER PT J AU Wick, DV Martinez, T Restaino, SR Stone, BR AF Wick, DV Martinez, T Restaino, SR Stone, BR TI Foveated imaging demonstration SO OPTICS EXPRESS LA English DT Article ID SYSTEM AB A wide field-of-view (FOV), theoretically diffraction-limited imaging system is demonstrated using a single positive lens (a singlet), a reflective liquid crystal spatial light modulator (SLM), a turning mirror and a CCD camera. The SLM is used to correct the off-axis aberrations that would otherwise limit the useful FOV of our system. Foveated imaging refers to the variation in spatial resolution across the image caused by using the SLM in this manner. (C) 2002 Optical Society of America. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. USAF, Res Lab, DEBS, Kirtland AFB, NM 87117 USA. Mission Res Corp, Dayton, OH 45430 USA. RP Wick, DV (reprint author), Sandia Natl Labs, POB 5800,MS 1188, Albuquerque, NM 87185 USA. EM dvwick@sandia.gov; ty.martinez@kirtland.af.mil; sergio.restaino@kirtland.af.mil; bstone@mrcday.com NR 8 TC 45 Z9 48 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD JAN 14 PY 2002 VL 10 IS 1 BP 60 EP U2 DI 10.1364/OE.10.000060 PG 6 WC Optics SC Optics GA 511GE UT WOS:000173255600009 PM 19424331 ER PT J AU Adcox, K Adler, SS Ajitanand, NN Akiba, Y Alexander, J Aphecetche, L Arai, Y Aronson, SH Averbeck, R Awes, TC Barish, KN Barnes, PD Barrette, J Bassalleck, B Bathe, S Baublis, V Bazilevsky, A Belikov, S Bellaiche, FG Belyaev, ST Bennett, MJ Berdnikov, Y Botelho, S Brooks, ML Brown, DS Bruner, N Bucher, D Buesching, H Bumazhnov, V Bunce, G Burward-Hoy, J Butsyk, S Carey, TA Chand, R Chang, J Chang, WC Chavez, LL Chernichenko, S Chi, CY Chiba, J Chiu, M Choudhury, RK Christ, T Chujo, T Chung, MS Chung, P Cianciolo, V Cole, BA D'Enterria, DG David, G Delagrange, H Denisov, A Deshpande, A Desmond, EJ Dietzsch, O Dinesh, BV Drees, A Durum, A Dutta, D Ebisu, K Efremenko, YV El Chenawi, K En'yo, H Esumi, S Ewell, L Ferdousi, T Fields, DE Fokin, SL Fraenkel, Z Franz, A Frawley, AD Fung, SY Garpman, S Ghosh, TK Glenn, A Godoi, AL Goto, Y Greene, SV Perdekamp, MG Gupta, SK Guryn, W Gustafsson, HA Haggerty, JS Hamagaki, H Hansen, AG Hara, H Hartouni, ER Hayano, R Hayashi, N He, X Hemmick, TK Heuser, JM Hibino, M Hill, JC Ho, DS Homma, K Hong, B Hoover, A Ichihara, T Imai, K Ippolitov, MS Ishihara, M Jacak, BV Jang, WY Jia, J Johnson, BM Johnson, SC Joo, KS Kametani, S Kang, JH Kann, M Kapoor, SS Kelly, S Khachaturov, B Khanzadeev, A Kikuchi, J Kim, DJ Kim, HJ Kim, SY Kim, YG Kinnison, WW Kistenev, E Kiyomichi, A Klein-Boesing, C Klinksiek, S Kochenda, L Kochetkov, V Koehler, D Kohama, T Kotchetkov, D Kozlov, A Kroon, RJ Kurita, K Kweon, MJ Kwon, Y Kyle, GS Lacey, R Lajoie, JG Lauret, J Lebedev, A Lee, DM Leitch, MJ Li, XH Li, Z Lim, DJ Liu, MX Liu, X Liu, Z Maguire, CF Mahon, J Makdisi, YI Manko, VI Mao, Y Mark, SK Markacs, S Martinez, G Marx, MD Masaike, A Matathias, F Matsumoto, T McGaughey, PL Melnikov, E Merschmeyer, M Messer, F Messer, M Miake, Y Miller, TE Milov, A Mioduszewski, S Mischke, RE Mishra, GC Mitchell, JT Mohanty, AK Morrison, DP Moss, JM Muhlbacher, F Muniruzzaman, M Murata, J Nagamiya, S Nagasaka, Y Nagle, JL Nakada, Y Nandi, BK Newby, J Nikkinen, L Nilsson, R Nishimura, S Nyanin, AS Nystrand, J O'Brien, E Ogilvie, CA Ohnishi, H Ojha, ID Ono, M Onuchin, V Oskarsson, A Osterman, L Otterlund, I Oyama, K Paffrath, L Palounek, APT Pantuev, VS Papavassiliou, V Pate, SF Peitzmann, T Petridis, AN Pinkenburg, C Pisani, RR Pitukhin, R Plasil, F Pollack, M Pope, K Purschke, ML Ravinovich, I Read, KF Reygers, K Riabov, V Riabov, Y Rosati, M Rose, AA Ryu, SS Saito, N Sakaguchi, A Sakaguchi, T Sako, H Sakuma, T Samsonov, V Sangster, TC Santo, R Sato, HD Sato, S Sawada, S Schlei, BR Schutz, Y Semenov, V Seto, R Shea, TK Shein, I Shibata, TA Shigaki, K Shiina, T Shin, YH Sibiriak, IG Silvermyr, D Sim, KS Simon-Gillo, J Singh, CP Singh, V Sivertz, M Soldatov, A Soltz, RA Sorensen, S Stankus, PW Starinsky, N Steinberg, R Stenlund, E Ster, A Stoll, SP Sugioka, M Sugitate, T Sullivan, JP Sumi, Y Sun, Z Suzuki, M Takagui, EM Taketani, A Tamai, M Tanaka, KH Tanaka, Y Taniguchi, E Tannenbaum, MJ Thomas, J Thomas, JH Thomas, TL Tian, W Tojo, J Torii, H Towell, RS Tserruya, I Tsuruoka, H Tsvetkov, AA Tuli, SK Tydesjo, H Tyurin, N Ushiroda, T van Hecke, HW Velissaris, C Velkovska, J Velkovsky, M Vinogradov, AA Volkov, MA Vorobyov, A Vznuzdaev, E Wang, H Watanabe, Y White, SN Witzig, C Wohn, FK Woody, CL Xie, W Yagi, K Yokkaichi, S Young, GR Yushmanov, IE Zajc, WA Zhang, Z Zhou, S AF Adcox, K Adler, SS Ajitanand, NN Akiba, Y Alexander, J Aphecetche, L Arai, Y Aronson, SH Averbeck, R Awes, TC Barish, KN Barnes, PD Barrette, J Bassalleck, B Bathe, S Baublis, V Bazilevsky, A Belikov, S Bellaiche, FG Belyaev, ST Bennett, MJ Berdnikov, Y Botelho, S Brooks, ML Brown, DS Bruner, N Bucher, D Buesching, H Bumazhnov, V Bunce, G Burward-Hoy, J Butsyk, S Carey, TA Chand, R Chang, J Chang, WC Chavez, LL Chernichenko, S Chi, CY Chiba, J Chiu, M Choudhury, RK Christ, T Chujo, T Chung, MS Chung, P Cianciolo, V Cole, BA D'Enterria, DG David, G Delagrange, H Denisov, A Deshpande, A Desmond, EJ Dietzsch, O Dinesh, BV Drees, A Durum, A Dutta, D Ebisu, K Efremenko, YV El Chenawi, K En'yo, H Esumi, S Ewell, L Ferdousi, T Fields, DE Fokin, SL Fraenkel, Z Franz, A Frawley, AD Fung, SY Garpman, S Ghosh, TK Glenn, A Godoi, AL Goto, Y Greene, SV Perdekamp, MG Gupta, SK Guryn, W Gustafsson, HA Haggerty, JS Hamagaki, H Hansen, AG Hara, H Hartouni, ER Hayano, R Hayashi, N He, X Hemmick, TK Heuser, JM Hibino, M Hill, JC Ho, DS Homma, K Hong, B Hoover, A Ichihara, T Imai, K Ippolitov, MS Ishihara, M Jacak, BV Jang, WY Jia, J Johnson, BM Johnson, SC Joo, KS Kametani, S Kang, JH Kann, M Kapoor, SS Kelly, S Khachaturov, B Khanzadeev, A Kikuchi, J Kim, DJ Kim, HJ Kim, SY Kim, YG Kinnison, WW Kistenev, E Kiyomichi, A Klein-Boesing, C Klinksiek, S Kochenda, L Kochetkov, V Koehler, D Kohama, T Kotchetkov, D Kozlov, A Kroon, RJ Kurita, K Kweon, MJ Kwon, Y Kyle, GS Lacey, R Lajoie, JG Lauret, J Lebedev, A Lee, DM Leitch, MJ Li, XH Li, Z Lim, DJ Liu, MX Liu, X Liu, Z Maguire, CF Mahon, J Makdisi, YI Manko, VI Mao, Y Mark, SK Markacs, S Martinez, G Marx, MD Masaike, A Matathias, F Matsumoto, T McGaughey, PL Melnikov, E Merschmeyer, M Messer, F Messer, M Miake, Y Miller, TE Milov, A Mioduszewski, S Mischke, RE Mishra, GC Mitchell, JT Mohanty, AK Morrison, DP Moss, JM Muhlbacher, F Muniruzzaman, M Murata, J Nagamiya, S Nagasaka, Y Nagle, JL Nakada, Y Nandi, BK Newby, J Nikkinen, L Nilsson, R Nishimura, S Nyanin, AS Nystrand, J O'Brien, E Ogilvie, CA Ohnishi, H Ojha, ID Ono, M Onuchin, V Oskarsson, A Osterman, L Otterlund, I Oyama, K Paffrath, L Palounek, APT Pantuev, VS Papavassiliou, V Pate, SF Peitzmann, T Petridis, AN Pinkenburg, C Pisani, RR Pitukhin, R Plasil, F Pollack, M Pope, K Purschke, ML Ravinovich, I Read, KF Reygers, K Riabov, V Riabov, Y Rosati, M Rose, AA Ryu, SS Saito, N Sakaguchi, A Sakaguchi, T Sako, H Sakuma, T Samsonov, V Sangster, TC Santo, R Sato, HD Sato, S Sawada, S Schlei, BR Schutz, Y Semenov, V Seto, R Shea, TK Shein, I Shibata, TA Shigaki, K Shiina, T Shin, YH Sibiriak, IG Silvermyr, D Sim, KS Simon-Gillo, J Singh, CP Singh, V Sivertz, M Soldatov, A Soltz, RA Sorensen, S Stankus, PW Starinsky, N Steinberg, R Stenlund, E Ster, A Stoll, SP Sugioka, M Sugitate, T Sullivan, JP Sumi, Y Sun, Z Suzuki, M Takagui, EM Taketani, A Tamai, M Tanaka, KH Tanaka, Y Taniguchi, E Tannenbaum, MJ Thomas, J Thomas, JH Thomas, TL Tian, W Tojo, J Torii, H Towell, RS Tserruya, I Tsuruoka, H Tsvetkov, AA Tuli, SK Tydesjo, H Tyurin, N Ushiroda, T van Hecke, HW Velissaris, C Velkovska, J Velkovsky, M Vinogradov, AA Volkov, MA Vorobyov, A Vznuzdaev, E Wang, H Watanabe, Y White, SN Witzig, C Wohn, FK Woody, CL Xie, W Yagi, K Yokkaichi, S Young, GR Yushmanov, IE Zajc, WA Zhang, Z Zhou, S CA PHENIX Collaboration TI Suppression of hadrons with large transverse momentum in central Au+Au collisions at root s(NN)=130 GeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID SPECTRA AB Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 Gev/c < P-T < 5 GeV/c have been measured by the PHENIX experiment at RHIC in Au + Au collisions at rootS(NN) = 130 GeV. At high p(T) the spectra from peripheral nuclear collisions are consistent with scaling the spectra from p + p collisions by the average number of binary nucleon-nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary-scaled p + p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear-medium effect in central nuclear collisions at RHIC energies. C1 Vanderbilt Univ, Nashville, TN 37235 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Bhabha Atom Res Ctr, Bombay 400085, Maharashtra, India. Brookhaven Natl Lab, Upton, NY 11973 USA. Banaras Hindu Univ, Dept Phys, Varanasi 221005, Uttar Pradesh, India. Univ Calif Riverside, Riverside, CA 92521 USA. China Inst Atom Energy, Beijing, Peoples R China. Univ Tokyo, Grad Sch Sci, Ctr Nucl Study, Bunkyo Ku, Tokyo 1130033, Japan. Columbia Univ, New York, NY 10027 USA. Nevis Labs, Irvington, NY 10533 USA. Florida State Univ, Tallahassee, FL 32306 USA. Georgia State Univ, Atlanta, GA 30303 USA. Hiroshima Univ, Higashihiroshima 7398526, Japan. Inst High Energy Phys, Protvino, Russia. Iowa State Univ, Ames, IA 50011 USA. High Energy Accelerator Res Org, KEK, Tsukuba, Ibaraki 3050801, Japan. Korea Univ, Seoul 136701, South Korea. Russian Res Ctr, Kurchatov Inst, Moscow, Russia. Kyoto Univ, Kyoto 606, Japan. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Lund Univ, Dept Phys, SE-22100 Lund, Sweden. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Munster, Inst Kernphys, D-48149 Munster, Germany. Myongji Univ, Yongin 449728, Kyonggido, South Korea. Nagasaki Inst Appl Sci, Nagasaki 8510193, Japan. Univ New Mexico, Albuquerque, NM 87131 USA. New Mexico State Univ, Las Cruces, NM 88003 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. PNPI, Gatchina, Russia. RIKEN, Wako, Saitama 3510198, Japan. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, Brazil. Univ Nantes, Ecole Mines Nantes, SUBATECH, CNRS,IN2P3, F-44307 Nantes 3, France. St Petersburg State Tech Univ, St Petersburg, Russia. Univ Tennessee, Knoxville, TN 37996 USA. Tokyo Inst Technol, Dept Phys, Tokyo 1528551, Japan. Univ Tokyo, Tokyo, Japan. Univ Tsukuba, Inst Phys, Tsukuba, Ibaraki 305, Japan. Vanderbilt Univ, Nashville, TN 37235 USA. Waseda Univ, Adv Res Inst Sci & Engn, Shinjuku Ku, Tokyo 1620044, Japan. Weizmann Inst Sci, IL-76100 Rehovot, Israel. Yonsei Univ, IPAP, Seoul 120749, South Korea. KFKI Res Inst Particle & Nucl Phys, Budapest, Hungary. RP Adcox, K (reprint author), Vanderbilt Univ, 221 Kirkland Hall, Nashville, TN 37235 USA. RI seto, richard/G-8467-2011; En'yo, Hideto/B-2440-2015; Hayano, Ryugo/F-7889-2012; HAMAGAKI, HIDEKI/G-4899-2014; Durum, Artur/C-3027-2014; Peitzmann, Thomas/K-2206-2012; Yokkaichi, Satoshi/C-6215-2017; Taketani, Atsushi/E-1803-2017; Semenov, Vitaliy/E-9584-2017 OI Hayano, Ryugo/0000-0002-1214-7806; Peitzmann, Thomas/0000-0002-7116-899X; Taketani, Atsushi/0000-0002-4776-2315; NR 21 TC 811 Z9 811 U1 9 U2 30 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 14 PY 2002 VL 88 IS 2 AR 022301 DI 10.1103/PhysRevLett.88.022301 PG 6 WC Physics, Multidisciplinary SC Physics GA 512YF UT WOS:000173350600008 PM 11801005 ER PT J AU Back, BB Baker, MD Barton, DS Betts, RR Bindel, R Budzanowski, A Busza, W Carroll, A Corbo, J Decowski, MP Garcia, E George, N Gulbrandsen, K Gushue, S Halliwell, C Hamblen, J Henderson, C Hicks, D Hofman, D Hollis, RS Holynski, R Holzman, B Iordanova, A Johnson, E Kane, J Katzy, J Khan, N Kucewicz, W Kulinich, P Kuo, CM Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, A Mulmenstadt, J Nouicer, R Olszewski, A Pak, R Park, IC Pernegger, H Rafelski, M Rbeiz, M Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Rosenberg, L Sagerer, J Sarin, P Sawicki, P Skulski, W Steadman, SG Steinberg, P Stephans, GSF Stodulski, M Sukhanov, A Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B AF Back, BB Baker, MD Barton, DS Betts, RR Bindel, R Budzanowski, A Busza, W Carroll, A Corbo, J Decowski, MP Garcia, E George, N Gulbrandsen, K Gushue, S Halliwell, C Hamblen, J Henderson, C Hicks, D Hofman, D Hollis, RS Holynski, R Holzman, B Iordanova, A Johnson, E Kane, J Katzy, J Khan, N Kucewicz, W Kulinich, P Kuo, CM Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, A Mulmenstadt, J Nouicer, R Olszewski, A Pak, R Park, IC Pernegger, H Rafelski, M Rbeiz, M Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Rosenberg, L Sagerer, J Sarin, P Sawicki, P Skulski, W Steadman, SG Steinberg, P Stephans, GSF Stodulski, M Sukhanov, A Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B CA PHOBOS Collaboration TI Energy dependence of particle multiplicities in central Au+Au collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; PLUS AU REACTIONS; EXCITATION-FUNCTION; CHARGED-PARTICLES; DENSITIES; K+ AB We present the first measurement of the pseudorapidity density of primary charged particles in Au + Au collisions at roots(NN) = 200 GeV. For the 6% most central collisions, we obtain dN(ch)/deta\(\eta\<1) = 650 +/- 35(syst). Compared to collisions at &RADIC;S-NN = 130 GeV, the highest energy studied previously, an increase by a factor of 1.14 +/- 0.05 at 90% confidence level, is found. The energy dependence of the pseudorapidity density is discussed in comparison with data from proton-induced collisions and theoretical predictions. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, CA Dept, Upton, NY 11973 USA. Inst Nucl Phys, Krakow, Poland. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Natl Cent Univ, Dept Phys, Chungli 32054, Taiwan. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Univ Maryland, Dept Chem, College Pk, MD 20742 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. RP Back, BB (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RI Decowski, Patrick/A-4341-2011; Mignerey, Alice/D-6623-2011; Muelmenstaedt, Johannes/K-2432-2015; OI Muelmenstaedt, Johannes/0000-0003-1105-6678; Holzman, Burt/0000-0001-5235-6314 NR 30 TC 123 Z9 124 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 14 PY 2002 VL 88 IS 2 AR 022302 DI 10.1103/PhysRevLett.88.022302 PG 4 WC Physics, Multidisciplinary SC Physics GA 512YF UT WOS:000173350600009 PM 11801006 ER PT J AU Kaindl, RA Carnahan, MA Orenstein, J Chemla, DS Christen, HM Zhai, HY Paranthaman, M Lowndes, DH AF Kaindl, RA Carnahan, MA Orenstein, J Chemla, DS Christen, HM Zhai, HY Paranthaman, M Lowndes, DH TI Far-infrared optical conductivity gap in superconducting MgB2 films SO PHYSICAL REVIEW LETTERS LA English DT Article AB We report the first study of the optical conductivity of MgG(2) covering the range of its lowest-energy superconducting gap. Terahertz time-domain spectroscopy is utilized to determine the complex, frequency-dependent conductivity sigma(omega)) of thin films. The imaginary part reveals an inductive response due to the emergence of the superconducting condensate. The real part exhibits a strong depletion of oscillator strength near 5 meV resulting from the opening of a superconducting energy gap. The gap ratio of 2Delta(0)/k(B)T(C) approximate to 1.9 is well below the weak-coupling value, pointing to complex behavior in this novel superconductor. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37931 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Christen, Hans/H-6551-2013; Orenstein, Joseph/I-3451-2015; Paranthaman, Mariappan/N-3866-2015 OI Christen, Hans/0000-0001-8187-7469; Paranthaman, Mariappan/0000-0003-3009-8531 NR 26 TC 66 Z9 67 U1 2 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 14 PY 2002 VL 88 IS 2 AR 027003 DI 10.1103/PhysRevLett.88.027003 PG 4 WC Physics, Multidisciplinary SC Physics GA 512YF UT WOS:000173350600032 PM 11801029 ER PT J AU Meldrum, A Boatner, LA Ewing, RC AF Meldrum, A Boatner, LA Ewing, RC TI Nanocrystalline zirconia can be amorphized by ion irradiation SO PHYSICAL REVIEW LETTERS LA English DT Article ID TETRAGONAL ZIRCONIA; SURFACE ENERGIES; PHASE-TRANSITION; CUBIC ZIRCONIA; STABILITY; IMPLANTATION; PLUTONIUM; PRESSURE; OXIDES; WASTE AB Nanocrystalline composites are finding applications in high-radiation environments due to their excellent mechanical and electronic properties. We show, however, that at the smallest particle sizes, radiation damage effects can be so strongly enhanced that under the right conditions, materials that have never been made amorphous can become highly susceptible to irradiation-induced amorphization. Because light-weight, high-strength nanocomposites are potential materials for spacecraft shielding and sensor systems, these fundamental results have significant implications for the design and selection of materials to be used in environments where a large ion flux will be encountered. C1 Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA. RP Meldrum, A (reprint author), Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. NR 29 TC 55 Z9 57 U1 2 U2 24 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 14 PY 2002 VL 88 IS 2 AR 025503 DI 10.1103/PhysRevLett.88.025503 PG 4 WC Physics, Multidisciplinary SC Physics GA 512YF UT WOS:000173350600027 PM 11801024 ER PT J AU Kertesz, V Dunn, NM Van Berkel, GJ AF Kertesz, V Dunn, NM Van Berkel, GJ TI Electrochemistry-electrospray-mass spectrometry study of cesium uptake in nickel hexacyanoferrate films SO ELECTROCHIMICA ACTA LA English DT Article DE cesium; hexacyanoferrates; electrodeposition; modified electrode; electrospray-mass spectrometry ID ANODIC-STRIPPING VOLTAMMETRY; QUARTZ-CRYSTAL MICROBALANCE; PRETREATMENT COUPLED ONLINE; PROBE BEAM DEFLECTION; SWITCHED ION-EXCHANGE; FLOW CELL; REDOX REACTIONS; SIGNAL ENHANCEMENT; ICP-MS; RADIOTRACER AB The electrochemically-controlled uptake and release of Cs+ by nickel hexacyanoferrate thin-film electrodes that were prepared with different counter cations (Li+, Na+, K+, Rb+, or Cs+) were examined using a thin-layer flow cell coupled on-line with electrospray-mass spectrometry (ES-MS). A potential step technique was used to control the uptake and release of the cations by the films. Performance of the different films in terms of Cs+ capacity, Cs+ uptake selectivity versus the other alkali metal ions, film stability, and the effect of a saline matrix on Cs+ uptake were examined. These results show that the electrochemistry-mass spectrometry (EC-MS) combination provides rapid, Cs+ specific information concerning the films that is similar to or complementary to that information which might be obtained using conventional electrochemical approaches. Information that cannot be obtained electrochemically (e.g. isotopic distributions of metal ions accumulated and released) might also be gathered. Any number of electrode reactions involving ion uptake and release might be studied using this approach. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Organ & Biol Mass Spectrometry Grp, Div Chem Sci, Oak Ridge, TN 37381 USA. RI Kertesz, Vilmos/M-8357-2016 OI Kertesz, Vilmos/0000-0003-0186-5797 NR 31 TC 32 Z9 32 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD JAN 11 PY 2002 VL 47 IS 7 BP 1035 EP 1042 DI 10.1016/S0013-4686(01)00828-3 PG 8 WC Electrochemistry SC Electrochemistry GA 518NJ UT WOS:000173674500003 ER PT J AU Cherrak, DE Al-Bokari, M Drumm, EC Guiochon, G AF Cherrak, DE Al-Bokari, M Drumm, EC Guiochon, G TI Behavior of packing materials in axially compressed chromatographic columns SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE column packing; axial compression; shear stress; wall effects; thiourea; phenyloctane ID SIZE-EXCLUSION CHROMATOGRAPHY; PERFORMANCE LIQUID-CHROMATOGRAPHY; CONSOLIDATION; POLYPEPTIDES AB The behavior of a packing material (Luna C-18 from Phenomenex, Torrance, CA, USA) was studied during the consolidation of a column bed under axial compression stress. The kinetics of this consolidation, the permeability and efficiency of the columns obtained, and the reproducibility of these column properties were measured under different conditions. The consolidation process and the column properties are considerably affected by the friction between the packing material in the bed and the column wall. Clear evidence of this wall effect was demonstrated. The apparent permeability of columns consolidated under the same axial stress increases with increasing column length. The apparent modulus of elasticity of the beds increases with increasing column length. The shear resistance between the packed bed and the column wall was measured for columns of different lengths. It increases rapidly with increasing bed length. The column efficiency for thiourea (unretained) and phenyloctane (retention factor, k'=1) was much poorer after recompression than after the first compression. It depended little on the compression stress. The effect of the column length was small. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Civil & Environm Engn, Knoxville, TN 37996 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. OI Drumm, Eric/0000-0001-9491-0934 NR 29 TC 5 Z9 8 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JAN 11 PY 2002 VL 943 IS 1 BP 15 EP 31 DI 10.1016/S0021-9673(01)01432-7 PG 17 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 508NE UT WOS:000173094700002 PM 11820276 ER PT J AU Faulon, JL Rintoul, MD Young, MM AF Faulon, JL Rintoul, MD Young, MM TI Constrained walks and self-avoiding walks: implications for protein structure determination SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article AB We prove that n-step walks and self-avoiding walks on the 2D honeycomb, 2D square, 3D diamond and 3D cubic lattices can be uniquely characterized (canonized) with no more than n Euclidian distances. We also demonstrate that these canonical distances can be obtained with O(n) physical measurements. Finally, while the protein-folding problem on lattices is known to be strongly NP-hard, we prove that lattice protein structures of size n matching O(n) canonical distance measurements can be determined in linear time. C1 Sandia Natl Labs, Computat Comp & Math Ctr, Livermore, CA 94551 USA. Sandia Natl Labs, Biosyst Res Dept, Livermore, CA 94551 USA. RP Faulon, JL (reprint author), Sandia Natl Labs, Computat Comp & Math Ctr, POB 969, Livermore, CA 94551 USA. NR 8 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD JAN 11 PY 2002 VL 35 IS 1 BP 1 EP 19 DI 10.1088/0305-4470/35/1/301 PG 19 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 518JZ UT WOS:000173665900003 ER PT J AU Mao, S Smith, MC Wozniak, P Udalski, A Szymanski, M Kubiak, M Pietrzynski, G Soszynski, I Zebrun, K AF Mao, S Smith, MC Wozniak, P Udalski, A Szymanski, M Kubiak, M Pietrzynski, G Soszynski, I Zebrun, K TI Optical Gravitational Lensing Experhnent OGLE-1999-BUL-32: the longest ever microlensing event - evidence for a stellar mass black hole? SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE black hole physics; gravitational lensing; Galaxy : bulge; Galaxy : centre ID DIFFERENCE IMAGE-ANALYSIS; GALACTIC BULGE; PARALLAX; SUBTRACTION; ASTROMETRY; PHOTOMETRY; PROJECT; MOTIONS; MACHOS; SEARCH AB We describe the discovery of the longest microlensing event ever observed, OGLE-1999-BUL-32, also independently identified by the MACHO collaboration as MACHO-99-BLG-22. This unique event has an Einstein radius crossing time of 640 d. The high-quality data obtained with difference image analysis shows a small but significant parallax signature. This parallax effect allows one to determine the Einstein radius projected on to the observer plane as (r) over tilde (E) approximate to 29.1 au. The transverse velocity projected on to the observer plane is about 79 km s(-1). We argue that the lens is likely to have a mass of at least a few solar masses, i.e. it could be a stellar black hole. The black hole hypothesis can be tested using the astrometric microlensing signature with the soon-to-be installed Advanced Camera for Surveys on board the Hubble Space Telescope. Deep X-ray and radio images may also be useful for revealing the nature of the object. C1 Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. Princeton Univ Observ, Princeton, NJ 08544 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Warsaw Observ, PL-00478 Warsaw, Poland. Univ Concepcion, Dept Fis, Concepcion, Chile. RP Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. EM smao@jb.man.ac.uk; msmith@jb.man.ac.uk; wozniak@lanl.gov; udalski@astrouw.edu.pl; msz@astrouw.edu.pl; mk@astrouw.edu.pl; pietrzyn@astrouw.edu.pl; soszynsk@astrouw.edu.pl; zebrun@astrouw.edu.pl NR 33 TC 54 Z9 54 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JAN 11 PY 2002 VL 329 IS 2 BP 349 EP 354 DI 10.1046/j.1365-8711.2002.04986.x PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 516ZV UT WOS:000173587400014 ER PT J AU Eremin, V Verbitskaya, E Li, Z AF Eremin, V Verbitskaya, E Li, Z TI Effect of radiation induced deep level traps on Si detector performance SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl ID RESISTIVITY SILICON DETECTORS; N-EFF; NEUTRON-IRRADIATION; TEMPERATURES; HARDNESS; DAMAGE; TCT AB The main factor. which leads to semiconductor detector degradation in high-energy physics experiments, is the introduction of lattice defects in the detector material produced by radiation. Based on the spectrum of radiation induced defects in the silicon bulk, the overview of effects and mechanisms responsible for the changes in the main detector parameters such as effective concentration of the space charge in the depleted region, space charge sign inversion, charge collection efficiency, and detector breakdown voltage are considered. Special attention is paid to the electric field distortion related with high concentration of radiation induced deep traps, which is the key question for the design of detectors operating at cryogenic temperature. In particular, the charge collection recovery at low temperature, often refereed as the Lazarus effect. and the limitation for the detection rate related to the polarization effect are considered. (C) 2002 Published by Elsevier Science B.V. C1 Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Eremin, V (reprint author), Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. RI Verbitskaya, Elena/D-1521-2014 NR 22 TC 32 Z9 32 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 537 EP 549 DI 10.1016/S0168-9002(01)01640-0 PG 13 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700002 ER PT J AU Eremin, V Verbitskaya, E Li, Z AF Eremin, V Verbitskaya, E Li, Z TI The origin of double peak electric field distribution in heavily irradiated silicon detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl ID DAMAGE AB The first observation of double peak (DP) electric field distribution in heavily neutron irradiated (> 10(14) n/cm(2)) semiconductor detectors has been published about 6 yr ago. However, this effect was not quantitatively analyzed up to now. The explanation of the DP electric field distribution presented in this paper is based on the properties of radiation induced deep levels in silicon, which act as deep traps, and on the distribution of the thermally generated free carrier concentration in the detector bulk. In the frame of this model, the earlier published considerations on the so-called "double junction (DJ) effect" are discussed as well. The comparison of the calculated electric field profiles at different temperatures with the experimental ones allows one to determine a set of deep levels. This set of deep levels, and their charge filling status are essential to the value and the distribution of space charge in the space charge region in the range of 305-240 K, which is actual temperature range for the main experiments at LHC where silicon detectors are used. This set of deep levels includes the levels located close to the midgap and does not contain the defects with the largest introduction rate -(C-i-O-i ) and (V-V). (C) 2002 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Verbitskaya, E (reprint author), Russian Acad Sci, AF Ioffe Physicotech Inst, 26 Politechnicheskaya Str, St Petersburg 194021, Russia. RI Verbitskaya, Elena/D-1521-2014 NR 11 TC 67 Z9 67 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 556 EP 564 DI 10.1016/S0168-9002(01)01642-4 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700004 ER PT J AU Niinikoski, TO Abreu, M Bell, W Berglund, P de Boer, W Borchi, E Borer, K Bruzzi, M Buontempo, S Casagrande, L Chapuy, S Cindro, V Collins, P D'Ambrosio, N Da Via, C Devine, SRH Dezillie, B Dimcovski, Z Eremin, V Esposito, A Granata, V Grigoriev, E Grohmann, S Hauler, F Heijne, E Heising, S Janos, S Jungermann, L Konorov, I Li, Z Lourenco, C Mikuz, M O'Shea, V Pagano, S Palmieri, VG Paul, S Pirollo, S Pretzl, K Mendes, PR Ruggiero, G Smith, K Sonderegger, P Sousa, P Verbitskaya, E Watts, S Zavrtanik, M AF Niinikoski, TO Abreu, M Bell, W Berglund, P de Boer, W Borchi, E Borer, K Bruzzi, M Buontempo, S Casagrande, L Chapuy, S Cindro, V Collins, P D'Ambrosio, N Da Via, C Devine, SRH Dezillie, B Dimcovski, Z Eremin, V Esposito, A Granata, V Grigoriev, E Grohmann, S Hauler, F Heijne, E Heising, S Janos, S Jungermann, L Konorov, I Li, Z Lourenco, C Mikuz, M O'Shea, V Pagano, S Palmieri, VG Paul, S Pirollo, S Pretzl, K Mendes, PR Ruggiero, G Smith, K Sonderegger, P Sousa, P Verbitskaya, E Watts, S Zavrtanik, M TI Radiation hardness of cryogenic silicon detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl ID CHARGE COLLECTION EFFICIENCY; TEMPERATURES AB We shall review test results which show that silicon detectors can withstand at 130 K temperature a fluence of 2 x 10(15)cm(-2) of 1 MeV neutrons, which is about 10 times higher than the fluence tolerated by the best detectors operated close to room temperature. The tests were carried out on simple pad devices and on microstrip detectors of different types. The devices were irradiated at room temperature using reactor neutrons, and in situ at low temperatures using high-energy protons and lead ions. No substantial difference was observed between samples irradiated at low temperature and those irradiated at room temperature. after beneficial annealing. The design of low-mass modules for low-temperature trackers is discussed briefly, together with the cooling circuits for small and large systems. (C) 2002 Elsevier Science B.V. All rights reserved. C1 CERN, CH-1211 Geneva, Switzerland. LIP, P-1000 Lisbon, Portugal. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Helsinki Univ Technol, Low Temp Lab, FI-02150 Espoo, Finland. Univ Karlsruhe, IEKP, D-76128 Karlsruhe, Germany. Univ Florence, Dipartimento Energet, I-50139 Florence, Italy. Univ Bern, LHEP, CH-3012 Bern, Switzerland. Univ Naples Federico II, Dipartimento Fis, I-80125 Naples, Italy. Ist Nazl Fis Nucl, I-80125 Naples, Italy. Univ Geneva, Dept Radiol, CH-1211 Geneva, Switzerland. Jozef Stefan Inst, Exp Particle Phys Dept, Ljubljana 1001, Slovenia. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Brookhaven Natl Lab, Upton, NY 11973 USA. Russian Acad Sci, AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. Tech Univ Munich, Phys Dept E18, D-85748 Garching, Germany. RP Niinikoski, TO (reprint author), CERN, CH-1211 Geneva, Switzerland. RI Zavrtanik, Marko/A-1524-2008; Rato Mendes, Pedro/F-8827-2010; Grigoriev, Eugene/K-6650-2013; O'Shea, Val/G-1279-2010; Verbitskaya, Elena/D-1521-2014; Bruzzi, Mara/K-1326-2015; Pagano, Sergio/C-5332-2008; Paul, Stephan/F-7596-2015; Paul, Stephan/K-9237-2016; Grohmann, Steffen/M-8671-2016 OI D'Ambrosio, Nicola/0000-0001-9849-8756; Abreu, Maria Conceicao/0000-0003-0093-7496; Zavrtanik, Marko/0000-0001-5606-6912; Rato Mendes, Pedro/0000-0001-9929-0869; Grigoriev, Eugene/0000-0001-7235-9715; O'Shea, Val/0000-0001-7183-1205; Bruzzi, Mara/0000-0001-7344-8365; Pagano, Sergio/0000-0001-6894-791X; Paul, Stephan/0000-0002-8813-0437; Paul, Stephan/0000-0002-8813-0437; Grohmann, Steffen/0000-0003-1298-5110 NR 8 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 569 EP 582 DI 10.1016/S0168-9002(01)01644-8 PG 14 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700006 ER PT J AU Ruggiero, G Abreu, M Bell, W Berglund, P de Boer, W Borer, K Buontempo, S Casagrande, L Chapuy, S Cindro, V Collins, P D'Ambrosio, N Da Via, C Devine, SRH Dezillie, B Dimcovski, Z Eremin, V Esposito, A Granata, V Grigoriev, E Grohmann, S Hauler, F Heijne, E Heising, S Janos, S Jungermann, L Konorov, I Li, Z Lourenco, C Mikuz, M Niinikoski, TO O'Shea, V Pagano, S Palmieri, VG Paul, S Pretzl, K Mendes, PR Smith, K Sonderegger, P Sousa, P Verbitskaya, E Watts, S Zavrtanik, M AF Ruggiero, G Abreu, M Bell, W Berglund, P de Boer, W Borer, K Buontempo, S Casagrande, L Chapuy, S Cindro, V Collins, P D'Ambrosio, N Da Via, C Devine, SRH Dezillie, B Dimcovski, Z Eremin, V Esposito, A Granata, V Grigoriev, E Grohmann, S Hauler, F Heijne, E Heising, S Janos, S Jungermann, L Konorov, I Li, Z Lourenco, C Mikuz, M Niinikoski, TO O'Shea, V Pagano, S Palmieri, VG Paul, S Pretzl, K Mendes, PR Smith, K Sonderegger, P Sousa, P Verbitskaya, E Watts, S Zavrtanik, M TI Silicon detectors irradiated "in situ" at cryogenic temperatures SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE cryogenics; silicon detectors ID CHARGE COLLECTION EFFICIENCY AB Though several studies have proved the radiation tolerance of silicon detectors at cryogenic temperatures, following room temperature irradiation, no previous investigation has studied the behaviour of detectors irradiated "in situ" at low temperatures. In this work, effects of irradiation of 450 GeV protons at 83 K will be presented, showing that after a dose of 1.2 x 10(15) p cm(-2) a charge collection efficiency (CCE) of 55% is reached at 200 V before the annealing. The same results were found at the end of the irradiation. after the sample has spent more then one year at room temperature, This shows that the CCE recovery by low temperature operation is not affected by the temperature of irradiation and by the reverse annealing. (C) 2002 Elsevier Science B.V. All rights reserved. C1 CERN, CH-1211 Geneva, Switzerland. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. LIP, P-1000 Lisbon, Portugal. Helsinki Univ Technol, Low Temp Lab, FI-02150 Espoo, Finland. Univ Karlsruhe, IEKP, D-76128 Karlsruhe, Germany. Univ Bern, LHEP, CH-3012 Bern, Switzerland. Univ Naples Federico II, Dipartimento Fis, I-80125 Naples, Italy. Ist Nazl Fis Nucl, I-80125 Naples, Italy. Univ Geneva, Dept Radiol, CH-1211 Geneva, Switzerland. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Brookhaven Natl Lab, Upton, NY 11973 USA. Russian Acad Sci, AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. Tech Univ Munich, Phys Dept E18, D-85748 Garching, Germany. Jozef Stefan Inst, Exp Particle Phys Dept, Ljubljana 1001, Slovenia. RP Ruggiero, G (reprint author), CERN, CH-1211 Geneva, Switzerland. RI Grohmann, Steffen/M-8671-2016; Zavrtanik, Marko/A-1524-2008; Rato Mendes, Pedro/F-8827-2010; Grigoriev, Eugene/K-6650-2013; O'Shea, Val/G-1279-2010; Verbitskaya, Elena/D-1521-2014; Pagano, Sergio/C-5332-2008; Paul, Stephan/F-7596-2015; Paul, Stephan/K-9237-2016 OI D'Ambrosio, Nicola/0000-0001-9849-8756; Grohmann, Steffen/0000-0003-1298-5110; Zavrtanik, Marko/0000-0001-5606-6912; Rato Mendes, Pedro/0000-0001-9929-0869; Grigoriev, Eugene/0000-0001-7235-9715; Abreu, Maria Conceicao/0000-0003-0093-7496; O'Shea, Val/0000-0001-7183-1205; Pagano, Sergio/0000-0001-6894-791X; Paul, Stephan/0000-0002-8813-0437; Paul, Stephan/0000-0002-8813-0437 NR 8 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 583 EP 587 DI 10.1016/S0168-9002(01)01645-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700007 ER PT J AU Li, Z Verbitskaya, E Eremin, V Dezillie, B Chen, W Bruzzi, M AF Li, Z Verbitskaya, E Eremin, V Dezillie, B Chen, W Bruzzi, M TI Radiation hard detectors from silicon enriched with both oxygen and thermal donors: improvements in donor removal and long-term stability with regard to neutron irradiation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl ID N-EFF AB Detectors made on the silicon wafers with high concentration of thermal donors (TD), which were introduced during the high temperature long time (HTLT) oxygenation procedure, have been investigated in the study of radiation hardness with regard to neutron irradiation and donor removal problems in irradiated high resistivity Si detectors. Two facts have been established as the evidence of radiation hardness improvement of HTLT(TD) Si detectors irradiated below similar to 10(14) n/cm(2) compared to detectors made on standard silicon wafers: the increase of space charge sign inversion fluence (of 1 MeV neutrons) due to lower initial Si resistivity dominated by TD, and the gain in the reverse annealing time constant tau favourable for this material. Coupled with extremely high radiation tolerance to protons observed earlier ("beta zero" behaviour in a wide range of fluence), detectors from HTLT(TD) Si may be unique for application in the experiments with multiple radiations. The changes in the effective space charge density (N-eff) in as-irradiated detectors as a function of neutron fluence have been fitted using three different models. It has been shown that a new model with a universal donor removal rate for both materials, and considering the contribution of non-removable TD to the N-eff provides good fit to the experimental data. A defect level related to TD has been observed in DLTS spectra of HTLT Si(TD) near T similar to 75K. The physics of donor removal in irradiated silicon detectors is discussed. (C) 2002 Published by Elsevier Science B.V. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 196140, Russia. CERN, Geneva, Switzerland. Univ Florence, Florence, Italy. RP Li, Z (reprint author), Brookhaven Natl Lab, Bldg 535B,POB 5000, Upton, NY 11973 USA. RI Verbitskaya, Elena/D-1521-2014; Bruzzi, Mara/K-1326-2015 OI Bruzzi, Mara/0000-0001-7344-8365 NR 13 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 628 EP 638 DI 10.1016/S0168-9002(01)01651-5 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700013 ER PT J AU Prettyman, TH Ianakiev, KD Soldner, SA Szeles, C AF Prettyman, TH Ianakiev, KD Soldner, SA Szeles, C TI Effect of differential bias on the transport of electrons in coplanar grid CdZnTe detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE cadmium zinc telluride; modeling; coplanar grid; hemispheric detector; resistivity; surface; passivation ID SEMICONDUCTOR RADIATION DETECTORS; CHARGE COLLECTION; STRIP DETECTORS; GENERATION; CD1-XZNXTE AB Segmented and pixilated electrode structures are used to compensate for poor hole transport in CdZnTe devices used for gamma-ray spectrometry and imaging. Efforts to model these structures have focused primarily on geometric effects; however, device performance also depends on the physical properties of the bulk and surface material, as well as the electrodes. In this paper, we describe experiments to characterize the electric field near the anode of a coplanar grid detector. The experiment is contrasted with a calculation that is based on an assumption commonly used to reduce the computational effort required to determine internal electric fields. Explanations for differences between the calculation and the experiment are proposed. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Los Alamos Natl Lab, Safeguards Sci & Technol Grp, Los Alamos, NM 87545 USA. eV PROD, Saxonburg, PA 16056 USA. RP Prettyman, TH (reprint author), Los Alamos Natl Lab, Safeguards Sci & Technol Grp, NIS-5,Mail Stop E540, Los Alamos, NM 87545 USA. OI Prettyman, Thomas/0000-0003-0072-2831 NR 23 TC 5 Z9 6 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 658 EP 664 DI 10.1016/S0168-9002(01)01660-6 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700017 ER PT J AU Xie, XB Cho, HS Liang, GW Huang, W Li, Z Chien, CY AF Xie, XB Cho, HS Liang, GW Huang, W Li, Z Chien, CY TI Electrical characterization of a radiation-hardened silicon pixel design for CMS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE silicon detector; pixel detector; radiation hardness; guard ring AB We have summarized our R&D on the radiation hardening and handling of high operating voltage for the CMS forward pixel detectors. More radiation-hardened silicon pixel sensors of configuration n(+)/n/p(+) with single-sided multi-guard ring structures have been developed and tested under the radiation environment expected at LHC. In the design, no guard ring is required on the n(+) side and guard rings on the p(+) side are always kept active before and after type inversion. The whole n(+) side is grounded and connected to readout-chip, which greatly simplifies detectors assembling and improves the stability of bump-bonded readout chip on the n(+) side. Samples had been irradiated to high fluence neutron and proton radiations to study the radiation hardness effects. Electrical characteristics such as leakage current, potential distributions over guard rings and full depletion voltage were measured under different temperatures. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. Yonsei Univ, Coll Hlth Sci, Dept Med Engn, Wonju 220710, South Korea. RP Xie, XB (reprint author), Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 665 EP 669 DI 10.1016/S0168-9002(01)01662-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700018 ER PT J AU Cihangir, S Kwan, S AF Cihangir, S Kwan, S TI Characterization of indium and solder bump bonding for pixel detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE pixel detectors; indium bumps; fine pitch solder bumps.; fluxless soldering AB A review of different bump-bonding processes used for pixel detectors is given. A large-scale test on daisy-chained components from two vendors has been carried out at Fermilab to characterize the yield of these processes. The vendors are Advanced Interconnect Technology Ltd. (AIT) of Hong Kong and MCNC in North Carolina, USA. C The results from this test are presented and technical challenges encountered are discussed. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Cihangir, S (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 2 TC 12 Z9 13 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 670 EP 675 DI 10.1016/S0168-9002(01)01771-5 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700019 ER PT J AU Atac, M Gobbi, B Cremaldi, L Hoffman, J AF Atac, M Gobbi, B Cremaldi, L Hoffman, J TI Radiation hardness studies of cooling fluids epoxies and capacitors for CMS pixel system SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 3rd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY JUN 28-30, 2000 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE CMS pixel tracking system AB Radiation hardness studies Of C6F14 Fluorinert (FC72) fluid, some epoxies and tantalum capacitors were studied for the Compact Muon Solenoidal (CMS) experiment at the Large Hadron Collider (LHC) of CERN. For a successful operation of Forward Silicon Pixel Tracker of the CMS, the cooling fluid. epoxies to be used and the filter capacitors of bias voltage supplies need to be radiation hard. It was also necessary to find out whether the cooling fluid would dissociate under the expected fluence and damage beryllium cooling channels of the Forward Silicon Pixel Discs. This paper is a report of our findings from the performed tests. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Northwestern Univ, Evanston, IL USA. Univ Mississippi, University, MS 38677 USA. RP Atac, M (reprint author), Fermilab Natl Accelerator Lab, POB 500,MS 222, Batavia, IL 60510 USA. NR 1 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2002 VL 476 IS 3 BP 676 EP 679 DI 10.1016/S0168-9002(01)01772-7 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 515LF UT WOS:000173496700020 ER PT J AU Rau, GH Caldeira, K AF Rau, GH Caldeira, K TI Minimizing effects of CO2 storage in oceans SO SCIENCE LA English DT Letter ID CARBONATE DISSOLUTION; DIOXIDE C1 Univ Calif Santa Cruz, Inst Marine Sci, Santa Cruz, CA 95064 USA. Lawrence Livermore Natl Lab, Climate & Carbon Cycle Modeling Grp, Livermore, CA 94550 USA. RP Rau, GH (reprint author), Univ Calif Santa Cruz, Inst Marine Sci, Santa Cruz, CA 95064 USA. RI Caldeira, Ken/E-7914-2011 NR 8 TC 8 Z9 8 U1 1 U2 4 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 11 PY 2002 VL 295 IS 5553 BP 275 EP 276 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 511RD UT WOS:000173278600023 PM 11789537 ER PT J AU De Chant, LJ AF De Chant, LJ TI A computationally implementable criterion for the solvability of boundary value problems on an infinite domain SO APPLIED MATHEMATICS AND COMPUTATION LA English DT Article DE boundary value problem; infinite domains; shooting method AB In this note we develop a simple, computationally implementable criterion to determine the solvability of boundary value problems. This criterion for solvability involves converting the boundary value problem to an initial value problem, forming an associated nonlinear boundary constraint, and computing necessary conditions for convergence using a coupled variational initial value problem. Source term and nearfield boundary condition effects are explicitly included. The solvability analysis is directly analogous to sampling convergence of a classical shooting method. Analytical and computational examples are provided which give confidence that this methodology is robust and has potentially wide applicability. Extensions to systems of equations are provided and demonstrated for a linear problem. (C) 2002 Elsevier Science Inc. All rights reserved. C1 Los Alamos Natl Lab, Hydrodynam Methods Grp, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. RP De Chant, LJ (reprint author), Los Alamos Natl Lab, Hydrodynam Methods Grp, Appl Theoret & Computat Phys Div, Mail Stop D-413, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0096-3003 J9 APPL MATH COMPUT JI Appl. Math. Comput. PD JAN 10 PY 2002 VL 125 IS 1 BP 35 EP 47 DI 10.1016/S0096-3003(00)00106-5 PG 13 WC Mathematics, Applied SC Mathematics GA 490EE UT WOS:000172036800003 ER PT J AU de Bernardis, P Ade, PAR Bock, JJ Bond, JR Borrill, J Boscaleri, A Coble, K Contaldi, CR Crill, BP de Troia, G Farese, P Ganga, K Giacometti, M Hivon, E Hristov, VV Iacoangeli, A Jaffe, AH Jones, WC Lange, AE Martinis, L Masi, S Mason, P Mauskopf, PD Melchiorri, A Montroy, T Netterfield, CB Pascale, E Piacentini, F Pogosyan, D Polenta, G Pongetti, F Prunet, S Romeo, G Ruhl, JE Scaramuzzi, F AF de Bernardis, P Ade, PAR Bock, JJ Bond, JR Borrill, J Boscaleri, A Coble, K Contaldi, CR Crill, BP de Troia, G Farese, P Ganga, K Giacometti, M Hivon, E Hristov, VV Iacoangeli, A Jaffe, AH Jones, WC Lange, AE Martinis, L Masi, S Mason, P Mauskopf, PD Melchiorri, A Montroy, T Netterfield, CB Pascale, E Piacentini, F Pogosyan, D Polenta, G Pongetti, F Prunet, S Romeo, G Ruhl, JE Scaramuzzi, F TI Multiple peaks in the angular power spectrum of the cosmic microwave background: Significance and consequences for cosmology SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; cosmological parameters; cosmology : observations ID AMERICAN TEST FLIGHT; RADIATION; UNIVERSE; FLUCTUATIONS; ANISOTROPIES; SUPERNOVAE; BOOMERANG; CLUSTERS; OMEGA AB Three peaks and two dips have been detected in the power spectrum of the cosmic microwave background by the BOOMERANG experiment, at and l = (213(-13)(+10)), (541(-32)(+20)), (845(-25)(+12)) and l = (416(-12)(+22)), (750(-750)(+20)), respectively. Using model-independent analyses, we find that all five features are statistically significant, and we measure their location and amplitude. These are consistent with the adiabatic inflationary model. We also calculate the mean and variance of the peak and dip locations and amplitudes in a large seven-dimensional parameter space of such models, which gives good agreement with the model-independent estimates. We forecast where the next few peaks and dips should be found if the basic paradigm is correct. We test the robustness of our results by comparing Bayesian marginalization techniques on this space with likelihood maximization techniques applied to a second seven-dimensional cosmological parameter space, using an independent computational pipeline, and find excellent agreement: Omega02/tot / (+0.05)(-0.06) versus 1.04 +/- 0.05, Omega(b) h(2) =0.022(-0.003)(+0.004) versus 0.019(-0.004)(+0.005), and n(s) = 0.96(-0.08)(+0.09) versus 0.90 +/- 0.08. The determination of the best fit by the maximization procedure effectively ignores nonzero optical depth of reionization tau(C) > 0, and the difference in primordial spectral index between the two methods is thus a consequence of the strong correlation of n(s) with the tau(C). C1 Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Univ London Queen Mary & Westfield Coll, London E1 4NS, England. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON, Canada. LBNL, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. CNR, IROE, I-50127 Florence, Italy. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. CALTECH, IPAC, Pasadena, CA 91125 USA. Univ Calif Berkeley, Dept Astron, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. ENEA, Frascati, Italy. Cardiff Univ, Dept Phys & Astron, Cardiff CF24 3YB, S Glam, Wales. Univ Oxford, Nucl & Astrophys Lab, Oxford OX 3RH, England. Univ Toronto, Dept Phys, Toronto, ON, Canada. Univ Toronto, Dept Astron, Toronto, ON, Canada. Ist Nazl Geofis, I-00161 Rome, Italy. RP de Bernardis, P (reprint author), Univ Roma La Sapienza, Dipartimento Fis, Piazzale Aldo Moro 2, I-00185 Rome, Italy. RI Jaffe, Andrew/D-3526-2009; OI ROMEO, Giovanni/0000-0002-5535-7803; de Bernardis, Paolo/0000-0001-6547-6446; Masi, Silvia/0000-0001-5105-1439; Polenta, Gianluca/0000-0003-4067-9196; Melchiorri, Alessandro/0000-0001-5326-6003; Piacentini, Francesco/0000-0002-5444-9327; Hivon, Eric/0000-0003-1880-2733 NR 44 TC 248 Z9 250 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2002 VL 564 IS 2 BP 559 EP 566 DI 10.1086/324298 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 509TZ UT WOS:000173166900004 ER PT J AU Drake, RP Robey, HF Hurricane, OA Zhang, Y Remington, BA Knauer, J Glimm, J Arnett, D Kane, JO Budil, KS Grove, J AF Drake, RP Robey, HF Hurricane, OA Zhang, Y Remington, BA Knauer, J Glimm, J Arnett, D Kane, JO Budil, KS Grove, J TI Experiments to produce a hydrodynamically unstable, spherically diverging system of relevance to instabilities in supernovae SO ASTROPHYSICAL JOURNAL LA English DT Article DE hydrodynamics; methods : laboratory; supernovae : general ID OMEGA-LASER-SYSTEM; FRONT TRACKING; CORE-COLLAPSE; INTENSE LASERS; DENSE-PLASMAS; NOVA LASER; ASTROPHYSICS; SN-1987A; 1987A; NUCLEOSYNTHESIS AB Results of the first spherically diverging, hydrodynamically unstable laboratory experiments of relevance to supernovae (SNe) are reported. The experiments are accomplished by using laser radiation to explode a hemispherical capsule, having a perturbed outer surface, which is embedded within a volume of low-density foam. The evolution of the experiment, like that of a supernova, is well described by the Euler equations. We have compared the experimental results to those of two-dimensional simulations using both a radiation-hydrodynamics code and a pure hydrodynamics code with front tracking. C1 Univ Michigan, Ann Arbor, MI 48109 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Drake, RP (reprint author), Univ Michigan, 2455 Hayward St, Ann Arbor, MI 48109 USA. RI Drake, R Paul/I-9218-2012 OI Drake, R Paul/0000-0002-5450-9844 NR 49 TC 40 Z9 41 U1 1 U2 14 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2002 VL 564 IS 2 BP 896 EP 908 DI 10.1086/324194 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 509TZ UT WOS:000173166900033 ER PT J AU Stanley, SA Sarkar, S Mellado, JP AF Stanley, SA Sarkar, S Mellado, JP TI A study of the flow-field evolution and mixing in a planar turbulent jet using direct numerical simulation SO JOURNAL OF FLUID MECHANICS LA English DT Article ID DEPENDENT BOUNDARY-CONDITIONS; FINITE-DIFFERENCE SCHEMES; LARGE-EDDY SIMULATION; HYPERBOLIC SYSTEMS; SHEAR LAYERS; INSTABILITY; TRANSITION AB Turbulent plane jets are prototypical free shear flows of practical interest in propulsion. combustion and environmental flows. While considerable experimental research has been performed on planar jets, very few computational studies exist. To the authors' knowledge, this is the first computational study of spatially evolving three-dimensional planar turbulent jets utilizing direct numerical simulation. Jet growth rates as well as the mean velocity, mean scalar and Reynolds stress profiles compare well with experimental data. Coherency spectra, vorticity visualization and autospectra are obtained to identify inferred structures. The development of the initial shear layer instability, as well as the evolution into the jet column mode downstream is captured well. The large- and small-scale anisotropies in the jet are discussed in detail. It is shown that, while the large scales in the flow field adjust slowly to variations in the local mean velocity gradients, the small scales adjust rapidly. Near the centreline of the jet, the small scales of turbulence are more isotropic. The mixing process is studied through analysis of the probability density functions of a passive scalar. Immediately after the rollup of vortical structures in the shear layers, the mixing process is dominated by large-scale engulfing of fluid. However, small-scale mixing dominates further downstream in the turbulent core of the self-similar region of the jet and a change from non-marching to marching PDFs is observed. Near the jet edges, the effects of large-scale engulfing of coflow fluid continue to influence the PDFs and non-marching type behaviour is observed. C1 Univ Calif San Diego, La Jolla, CA 92093 USA. RP Stanley, SA (reprint author), Lawrence Berkeley Natl Lab, 50A-1148, Berkeley, CA 94720 USA. RI Mellado, Juan Pedro/B-2000-2014 OI Mellado, Juan Pedro/0000-0001-7506-6539 NR 47 TC 101 Z9 106 U1 4 U2 25 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0022-1120 EI 1469-7645 J9 J FLUID MECH JI J. Fluid Mech. PD JAN 10 PY 2002 VL 450 BP 377 EP 407 PG 31 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 518LC UT WOS:000173669000015 ER PT J AU Szczepanski, J Banisaukas, J Vala, M Hirata, S Bartlett, RJ Head-Gordon, M AF Szczepanski, J Banisaukas, J Vala, M Hirata, S Bartlett, RJ Head-Gordon, M TI Vibrational and electronic Spectroscopy of the fluorene cation SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID DENSITY-FUNCTIONAL THEORY; AROMATIC HYDROCARBON CATIONS; MATRIX-ISOLATED NAPHTHALENE; EXCITATION-ENERGIES; EXCITED-STATES; ABSORPTION-SPECTRA; RADICAL CATIONS; CONFIGURATION-INTERACTION; INFRARED-SPECTROSCOPY; RESPONSE THEORY AB The fluorene cations, C13H10+ and C13D10+, have been formed by both electron impact ionization and vacuum ultraviolet photoionization, deposited in an argon matrix at 12K and studied via Fourier transform infrared and ultraviolet/visible absorption spectroscopy. Harmonic vibrational frequencies have been calculated using density functional theory (B3LYP/6-31G(d,p)) and vibrational band assignments made. Good agreement is found. Dramatic differences have been observed in the infrared band intensities of the cations compared to their neutral parents. Two excited electronic band systems have been observed and compared with previous photoelectron spectroscopic results. New calculations of the fluorene cation excited states have been performed using configuration interaction singles (CIS), CIS with a doubles correlation correction (CIS(D)), time-dependent Hartree-Fock (TDHF), and time-dependent density functional theory (TDDFT) with SVWN, BLYP, and B3LYP functionals. Theoretically, 12 low-lying excited states were found, six of which match closely with PES and optical band energies. Certain additional visible and IR bands, which appear only with higher electron impact ionization energies, are ascribed to the singly dehydrogenated neutral C13H9 (C13D9) fragment. TDDFT calculations on the excited states and B3LYP calculations of the infrared and Raman-active vibrations of the C13H9 (C13D9) product are consistent with this attribution. Evidence is presented for matrix-trapped cationic fragments, probably dehydrogenated species. C1 Univ Florida, Dept Chem, Gainesville, FL 32611 USA. Univ Florida, Ctr Chem Phys, Gainesville, FL 32611 USA. Univ Florida, Quantum Theory Project, Gainesville, FL 32611 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Vala, M (reprint author), Univ Florida, Dept Chem, Gainesville, FL 32611 USA. RI Bartlett, Rodney/F-6781-2011 OI Bartlett, Rodney/0000-0003-3865-9639 NR 55 TC 31 Z9 32 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 10 PY 2002 VL 106 IS 1 BP 63 EP 73 DI 10.1021/jp013059g PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 511GP UT WOS:000173256500008 ER PT J AU Takahashi, K Sawamura, S Dimitrijevic, NM Bartels, DM Jonah, CD AF Takahashi, K Sawamura, S Dimitrijevic, NM Bartels, DM Jonah, CD TI Transient negative species in supercritical carbon dioxide: Electronic spectra and reactions of CO2 anion clusters SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID COLLISIONAL CHARGE-TRANSFER; AB-INITIO; VANDERWAALS CLUSTERS; SOLID NEON; VIBRATIONAL-SPECTRA; PHOTO-DISSOCIATION; INFRARED-SPECTRA; SOLVENT DENSITY; ATTACHMENT; IONS AB Transient absorption spectra Mowing ionization of supercritical CO2 have been investigated using the pulse radiolysis technique. Absorption spectra measured from 400 to 800 nm suggest that at least two transient species absorb. We have previously reported that one species is (CO2)(2)(+). In the near UV region, we observed a transient species of which the lifetime and reactivity are different from the dimer cation. We assign this species to a dimer anion, (CO2)(2)(-), or an anion-molecule complex, (CO2-)(CO2)(x). Comparison with the photobleaching of CO2 anion clusters in solid rare gas matrixes and their reactivity with H-2 and O-2 confirm the assignment. Theoretical calculations, in which solvation is taken into account, are consistent with these assignments. It is well-established that the adiabatic electron affinity Of CO2 is negative, but the adiabatic electron affinity of CO2 dimer has been calculated to be 0.89 eV for D-2d symmetry (CO2)(2)(-) in the gas phase. The calculations predict that CO2- in a model continuum solvent is stable to autodetachment. C1 Hokkaido Univ, Div Quantum Energy Engn, Sapporo, Hokkaido 0608628, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. RP Takahashi, K (reprint author), Hokkaido Univ, Div Quantum Energy Engn, Sapporo, Hokkaido 0608628, Japan. RI Takahashi, Kenji/C-8846-2011; Takahashi, Kenji/F-4885-2014 NR 69 TC 12 Z9 12 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 10 PY 2002 VL 106 IS 1 BP 108 EP 114 DI 10.1021/jp012340s PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 511GP UT WOS:000173256500014 ER PT J AU Campbell, BJ Cheetham, AK AF Campbell, BJ Cheetham, AK TI Linear framework defects in zeolite mordenite SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SYNTHETIC MORDENITES; BETA AB Framework defect correlations are identified in zeolite mordenite that explain both X-ray powder diffraction anomalies and diffuse intensity features in previously reported electron diffraction data. The c/2 displacement of linear "chains" of framework material parallel to the main [001] channel are shown to selectively suppress and broaden the l = 2n + 1 Bragg reflections, thereby linking these framework defects to observed trends in a number of diffracted intensity ratios. At the same time, these defects are shown to produce thin sheets of diffuse scattering that are restricted to the l = 2n + 1 planes of reciprocal space, features that have been reported in electron diffraction studies of mordenite. An empirical relationship between the defect concentration and the framework aluminum content is also established. C1 Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. RP Campbell, BJ (reprint author), Argonne Natl Lab, Mat Sci Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Campbell, Branton/A-3990-2008 NR 23 TC 11 Z9 15 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 10 PY 2002 VL 106 IS 1 BP 57 EP 62 DI 10.1021/jp0128372 PG 6 WC Chemistry, Physical SC Chemistry GA 511GR UT WOS:000173256700011 ER PT J AU Wilder, JW Smith, DH AF Wilder, JW Smith, DH TI Comments on "Anomalous preservation of pure methane hydrate at 1 atm" SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ENDOTHERMIC DECOMPOSITION REACTIONS; ABNORMAL VARIATION; MECHANISM; KINETICS C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. W Virginia Univ, Dept Math, Morgantown, WV 26506 USA. W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA. RP Wilder, JW (reprint author), US DOE, Natl Energy Technol Lab, POB 880, Morgantown, WV 26507 USA. EM wilder@math.wvu.edu NR 17 TC 4 Z9 5 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 10 PY 2002 VL 106 IS 1 BP 226 EP 227 DI 10.1021/jp011450w PG 2 WC Chemistry, Physical SC Chemistry GA 511GR UT WOS:000173256700033 ER PT J AU Stern, LA Circone, S Kirby, SH Durham, WB AF Stern, LA Circone, S Kirby, SH Durham, WB TI Reply to "Comments on 'Anomalous preservation of pure methane hydrate at 1 atm'" SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article C1 US Geol Survey, Menlo Pk, CA 94025 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Stern, LA (reprint author), US Geol Survey, 345 Middlefield Rd,MS 977, Menlo Pk, CA 94025 USA. NR 3 TC 15 Z9 16 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 10 PY 2002 VL 106 IS 1 BP 228 EP 230 DI 10.1021/jp012189m PG 3 WC Chemistry, Physical SC Chemistry GA 511GR UT WOS:000173256700034 ER PT J AU Richie, ER Schumacher, A Angel, JM Holloway, M Rinchik, EM Magnuson, T AF Richie, ER Schumacher, A Angel, JM Holloway, M Rinchik, EM Magnuson, T TI The Polycomb-group gene eed regulates thymocyte differentiation and suppresses the development of carcinogen-induced T-cell lymphomas SO ONCOGENE LA English DT Article DE lymphomagenesis; Polycom-group gene; eed; thymocyte differentiation ID EXTRA SEX COMBS; METHYL-N-NITROSOUREA; MURINE THYMIC LYMPHOMAS; MOUSE CHROMOSOME-7; EVOLUTIONARY CONSERVATION; RAPID DEVELOPMENT; MICE; DROSOPHILA; PROTEIN; EXPRESSION AB The mouse Polycomb-group gene, embryonic ectoderm development (eed), appears to regulate cellular growth and differentiation in a developmental and tissue specific manner. During embryogenesis, eed regulates axial patterning, whereas in the adult eed represses proliferation of myeloid and B cell precursors. The present report demonstrates two novel functional activities of eed:alteration of thymocyte maturation and suppression of thymic lymphoma development. Mice that inherit the viable hypomorphic 17Rn5(1989SB) eed allele sustain a partial developmental block at or before the CD4(-)CD8(-)CD44(-) CD25(+) stage of thymocyte differentiation. Furthermore, mice that are homozygous or heterozygous for the hypomorphic eed allele have an increased incidence and decreased latency of N-methyl-N-nitrosourea-induced thymic lymphoma compared to wild-type littermates. These findings support the notion that Polycomb-group genes exert pleiotrophic effects dictated by developmental stage and cellular context. C1 Univ Texas, MD Anderson Canc Ctr, Dept Carcinogenesis, Sci Pk Res Div, Smithville, TX 78957 USA. Baylor Coll Med, Dept Mol & Human Genet, Houston, TX 77030 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Univ N Carolina, Dept Genet, Chapel Hill, NC 27599 USA. RP Richie, ER (reprint author), Univ Texas, MD Anderson Canc Ctr, Dept Carcinogenesis, Sci Pk Res Div, POB 389, Smithville, TX 78957 USA. FU NCI NIH HHS [CA16672]; NHGRI NIH HHS [HG00370]; NICHD NIH HHS [HD24462]; NIEHS NIH HHS [ES07784] NR 45 TC 33 Z9 33 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0950-9232 J9 ONCOGENE JI Oncogene PD JAN 10 PY 2002 VL 21 IS 2 BP 299 EP 306 DI 10.1038/sj/onc/1205051 PG 8 WC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity GA 507KG UT WOS:000173026200014 PM 11803473 ER PT J AU Trainor, TP Eng, PJ Brown, GE Robinson, IK De Santis, M AF Trainor, TP Eng, PJ Brown, GE Robinson, IK De Santis, M TI Crystal truncation rod diffraction study of the alpha-Al2O3 (1(1)over-bar-0 2) surface SO SURFACE SCIENCE LA English DT Article DE X-ray scattering, diffraction, and reflection; surface structure, morphology, roughness, and topography; aluminum oxide ID X-RAY-DIFFRACTION; ELECTRONIC-STRUCTURE; FIRST-PRINCIPLES; OXIDE SURFACES; SAPPHIRE 0001; PB(II); AL2O3; WATER; H2O; CRYSTALLOGRAPHY AB The structure of the alpha-Al2O3 (1-102) surface was examined using crystal truncation rod (CTR) diffraction. The initial surface was prepared by Ar-ion sputter and anneal cycles in O-2, which resulted in a clean (1 x 1) surface. CTR data were then collected for the clean and water-dosed surfaces (1 x 10(-8)-1.6 Torr) in a UHV diffraction chamber (base pressure approximate to1-3 x 10(-9) Torr). Water dosing had little effect on the diffraction data, suggesting that the initially prepared surface was fully oxygenated. Least-squares analysis of the CTR data resulted in two best fit models, a relaxed stoichiometric bulk termination and a relaxed bulk termination with a zero occupancy for the first layer of aluminum atoms. Crystal chemistry considerations suggest that the second model is the most plausible if the surface oxygens are protonated. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. Univ Chicago, Consortium Adv Radiat Sources, Chicago, IL 60637 USA. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. Stanford Univ, SLAC, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. CNRS, Cristallog Lab, F-38042 Grenoble, France. RP Trainor, TP (reprint author), Univ Chicago, Consortium Adv Radiat Sources, Bldg 434-A,9700 S Cass Ave, Argonne, IL 60439 USA. NR 49 TC 91 Z9 91 U1 0 U2 29 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JAN 10 PY 2002 VL 496 IS 3 BP 238 EP 250 DI 10.1016/S0039-6028(01)01617-X PG 13 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 511VK UT WOS:000173286100010 ER PT J AU Warren, S Reitzle, A Kazimirov, A Ziegler, JC Bunk, O Cao, LX Renner, FU Kolb, DM Bedzyk, MJ Zegenhagen, J AF Warren, S Reitzle, A Kazimirov, A Ziegler, JC Bunk, O Cao, LX Renner, FU Kolb, DM Bedzyk, MJ Zegenhagen, J TI A structure study of the electroless deposition of Au on Si(111): H SO SURFACE SCIENCE LA English DT Article DE electrochemical methods; X-ray standing waves; X-ray scattering, diffraction, and reflection; epitaxy; gold; silicon; single crystal surfaces; solid-liquid interfaces ID SURFACE 2ND-HARMONIC GENERATION; X-RAY; ELECTROCHEMICAL DEPOSITION; INITIAL-STAGE; AQUEOUS HF; GOLD; SILICON; GROWTH; SEMICONDUCTORS; MICROSCOPY AB Electroless deposition of gold in monolayer amounts on hydrogen terminated Si(111) was studied by a variety of structure sensitive techniques. Rutherford back scattering data revealed a linear relationship between the An coverage and the concentration of the An solution used for deposition. Atomic force microscopy and surface X-ray diffraction studies indicated cluster formation, with the Au(111) face epitaxially aligned to the Si(111):H substrate. However, Xray standing wave experiments at coverage below one monolayer suggested the formation of a gold layer. Both clusters and isolated An atoms appear to be present at all coverages, which is explained by the formation of type of Au 'wetting layer', in addition to cluster formation which increases as the coverage increases. (C) 2001 Elsevier Science B.V. All rights reserved. C1 European Synchrotron Radiat Facil, F-38043 Grenoble, France. Univ Ulm, Abt Elektrochem, D-89069 Ulm, Germany. Cornell Univ, Wilson Lab, CHESS, Ithaca, NY 14853 USA. Univ Hamburg, Inst Expt Phys 2, D-22761 Hamburg, Germany. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Northwestern Univ, Mat Res Ctr, Evanston, IL 60208 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Zegenhagen, J (reprint author), European Synchrotron Radiat Facil, Ave Jules Horowitz,BP-220, F-38043 Grenoble, France. RI Bedzyk, Michael/B-7503-2009; Bedzyk, Michael/K-6903-2013; Bunk, Oliver/B-7602-2013; Renner, Frank/G-1655-2014; OI Bunk, Oliver/0000-0001-6563-4053; Renner, Frank/0000-0003-0425-393X; Warren, Samantha/0000-0002-8525-7125 NR 26 TC 32 Z9 32 U1 2 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JAN 10 PY 2002 VL 496 IS 3 BP 287 EP 298 DI 10.1016/S0039-6028(01)01589-8 PG 12 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 511VK UT WOS:000173286100014 ER PT J AU Kamasa, P Buzin, A Pyda, M Wunderlich, B AF Kamasa, P Buzin, A Pyda, M Wunderlich, B TI The use of infra-red light-modulated temperature in DSC created by pulse-width modulation SO THERMOCHIMICA ACTA LA English DT Article DE temperature-modulated DSC; infra-red-modulated temperatures; pulse-width modulation ID DIFFERENTIAL SCANNING CALORIMETRY; HEAT-CAPACITY AB Infra-red light, generated by diodes, is applied to produce a sinusoidal temperature modulation in the standard heat-flux DSC of TA instruments. The temperature of the sample and reference are controlled by both, the original temperature controller of the instrument, and by the radiant energy generated by two high-power infra-red light-emitting diodes (LEDs). This allows for isothermal or quasi-isothermal experimentation in the standard mode of operation of the calorimeter. The additional infra-red irradiation is provided only for temperature modulation. The radiant energy transferred to the specimens is controlled by pulse-width modulation (PWM) which provides a high linearity in the temperature modulation program. This feature enables to obtain any arbitrary temperature profile with the limits of frequency set by the calorimeter response and speed of the computer. Simple electronics and a computer algorithm for the PWM control are described. The method was tested in the melting range of indium and by measurement of the heat capacity of sapphire (Al2O3) and polystyrene. The problem of frequency correction arising from a wide frequency range is analyzed and discussed. Published by Elsevier Science B. V. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Buzin, Alexander/H-5482-2011 NR 15 TC 4 Z9 4 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD JAN 10 PY 2002 VL 381 IS 2 BP 139 EP 146 DI 10.1016/S0040-6031(01)00649-9 PG 8 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 511JP UT WOS:000173261100004 ER PT J AU Wiench, JW Tischendorf, B Otaigbe, JU Pruski, M AF Wiench, JW Tischendorf, B Otaigbe, JU Pruski, M TI Structure of zinc polyphosphate glasses studied by two-dimensional solid and liquid state NMR SO JOURNAL OF MOLECULAR STRUCTURE LA English DT Article DE two-dimensional NMR methods; glass structure; zinc phosphate glasses ID NUCLEAR-MAGNETIC-RESONANCE; INTERMEDIATE-RANGE ORDER; DOUBLE-QUANTUM NMR; X-RAY-DIFFRACTION; PHOSPHATE-GLASSES; ROTATING SOLIDS; PULSE SEQUENCE; 2D NMR; SPECTROSCOPY; CRYSTALLINE AB A series of 10 binary zinc phosphate glasses with composition xZnO + (1 - x)P2O5 (0.35 less than or equal to x less than or equal to 0.80) is studied by means of two-dimensional (2D) solid and liquid state P-31 nuclear magnetic resonance (NMR). Double quantum (DQ) filtering method is used to probe P-31-P-31 connectivities through dipolar interactions in solid samples. Similar information is obtained using the correlation spectroscopy (COSY) experiment in solution. It is shown that these 2D NMR methods are capable of scrutinizing the evolution of glass structure versus x with improved precision. Varied relative concentrations of dimers, short or long branched chains and ring structures are found in glasses with different composition. Average chain length in the glasses is determined from the NMR results and compared with HPLC data and theoretical predictions. Finally, the evolution of glass structure is studied as a function of the synthesis temperature. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Pruski, M (reprint author), Iowa State Univ, Ames Lab, 230 Spedding Hall, Ames, IA 50011 USA. NR 54 TC 19 Z9 19 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2860 J9 J MOL STRUCT JI J. Mol. Struct. PD JAN 9 PY 2002 VL 602 SI SI BP 145 EP 157 AR PII S0022-2860(01)00769-4 DI 10.1016/S0022-2860(01)00769-4 PG 13 WC Chemistry, Physical SC Chemistry GA 557KU UT WOS:000175908400016 ER PT J AU Yamakov, V Wolf, D Phillpot, SR Gleiter, H AF Yamakov, V Wolf, D Phillpot, SR Gleiter, H TI Grain-boundary diffusion creep in nanocrystalline palladium by molecular-dynamics simulation SO ACTA MATERIALIA LA English DT Article DE computer simulation; nanocrystal; grain boundaries; diffusion; creep ID AMORPHOUS INTERGRANULAR FILMS; COPPER; TEMPERATURE; DEFORMATION; METALS; AU AB Molecular-dynamics (MD) simulations of fully three-dimensional (313), model nanocrystalline face-centered cubic metal microstructures are used to study grain-boundary (GB) diffusion creep, one mechanism considered to contribute to the deformation of nanocrystalline materials. To overcome the well-known limitations associated with the relatively short time interval used in our MD simulation (typically <10(-8) s), our simulations are performed at elevated temperatures where the distinct effects of GB diffusion are clearly identifiable. In order to prevent grain growth and thus to enable steady-state diffusion creep to be observed, our input microstructures were tailored to (1) have a uniform grain shape and a uniform grain size of nm dimensions and (2) contain only high-energy GBs which are known to exhibit rather fast, liquid-like self-diffusion. Our simulations reveal that under relatively high tensile stresses these microstructures. indeed. exhibit steady-state diffusion creep that is homogeneous, with a strain rate that agrees quantitatively with that given by the Coble-creep formula. The grain-size scaling of the Coble creep is found to decrease from d(-3) to d(-2) when the grain diameter becomes of the order of the GB width. For the first time a direct observation of the grain-boundary sliding as an accommodation mechanism for the Coble creep, known as Lifshitz sliding, is reported. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Forschungszentrum Karlsruhe, D-76021 Karlsruhe, Germany. RP Yamakov, V (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave,Bldg 212, Argonne, IL 60439 USA. RI Phillpot, Simon/J-9117-2012; OI Phillpot, Simon/0000-0002-7774-6535 NR 40 TC 265 Z9 274 U1 8 U2 101 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JAN 8 PY 2002 VL 50 IS 1 BP 61 EP 73 DI 10.1016/S1359-6454(01)00329-9 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 515FZ UT WOS:000173485900008 ER PT J AU Iakoucheva, LM Walker, RK van Houten, B Ackerman, EJ AF Iakoucheva, LM Walker, RK van Houten, B Ackerman, EJ TI Equilibrium and stop-flow kinetic studies of fluorescently labeled DNA substrates with DNA repair proteins XPA and replication protein A SO BIOCHEMISTRY LA English DT Article ID NUCLEOTIDE EXCISION-REPAIR; NUCLEIC-ACID INTERACTIONS; ULTRAVIOLET-DAMAGED DNA; SINGLE-STRANDED-DNA; ESCHERICHIA-COLI; ZINC METALLOPROTEIN; BINDING DOMAIN; TRP REPRESSOR; RECOGNITION; COMPLEX AB Nucleotide excision repair (NER) is a crucial pathway in the maintenance of genome stability requiring at least two dozen proteins. XPA and RPA have essential roles in the damage recognition step of NER. To better understand the mechanism of their interactions with DNA, we utilized equilibrium and stop-flow kinetic approaches with fluorescently labeled oligonucleotides. Fluorescein is a bona fide NER lesion because a circular plasmid with a single defined fluorescein was repaired by efficient extracts from Xenopus oocyte nuclei. Single-stranded and double-stranded oligonucleotides 5'-labeled with fluorescein were used in the subsequent studies. Oligonucleotide fluorescence was quenched upon specific binding to full-length recombinant Xenopus XPA (xXPA) and/or human RPA. The binding was highly sensitive to the buffer conditions. Analysis of equilibrium binding data with ds DNA and xXPA revealed a single dissociation constant (K-d) of 24.4 nM. Stopped-flow kinetic experiments were described by a first-order on-rate constant k(on) of 9.03 x 10(8) M-1 s(-1) and k(off) of 26.1 s(-1). From the ratio of off-rate to on-rate, a calculated K-d of 28.9 nM was obtained, revealing that the kinetic and equilibrium studies were consistent. The affinity of xXPA for ds undamaged DNA determined in our spectrofluorometry experiments was up to 3 orders of magnitude higher than previously reported values using different substrates, conditions, and assays [gel-shifts (EMSA), filter-binding, anisotropy, and surface plasmon resonance]. The same substrate DNA containing a 4-bp mismatch in the middle yielded a K-d five times higher (158 nM), indicating weaker binding by xXPA. The differences in Kd values for these two substrates were mainly attributable to the k(on), rather than k(off) rates. Fluorescence intensity changes upon interaction of xXPA with ss 50-mer were too low to calculate an accurate K-d. Although recombinant human RPA binding to the ds 50-mer was very weak (K-d > 1 mM), stop-flow and equilibrium measurements to ss oligonucleotide yielded K-d values of 96 and 20.3 nM, respectively, which correlated with previously reported values using gel mobility shift assays and a similarly sized poly-dT. Equilibrium and stop-flow measurements to the cognate and mismatched ds oligonucleotides using both xXPA and hRPA yielded a 2- to 3-fold increase in the K-d. C1 Pacific NW Natl Lab, PNNL, Mol Biosci Dept, Richland, WA 99352 USA. Univ Texas, Med Branch, Sealy Ctr Mol Sci, Galveston, TX 77555 USA. RP Ackerman, EJ (reprint author), Pacific NW Natl Lab, PNNL, Mol Biosci Dept, POB 999, Richland, WA 99352 USA. OI Iakoucheva, Lilia/0000-0002-4542-5219 NR 53 TC 15 Z9 15 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JAN 8 PY 2002 VL 41 IS 1 BP 131 EP 143 DI 10.1021/bi011041q PG 13 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 510PM UT WOS:000173216500015 PM 11772010 ER PT J AU Wang, XB Yang, X Wang, LS Nicholas, JB AF Wang, XB Yang, X Wang, LS Nicholas, JB TI Photodetachment and theoretical study of free and water-solvated nitrate anions, NO3-(H2O)(n) (n=0-6) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LASER-INDUCED FLUORESCENCE; PHOTOELECTRON-SPECTROSCOPY; GAS-PHASE; STATE DYNAMICS; NEGATIVE IONS; RADICAL NO3; BASIS-SETS; AB-INITIO; CLUSTERS; HYDRATION AB We investigated free and water-solvated gas phase nitrate anions, NO3-(H2O)(n) (n=0-6), by photodetachment photoelectron spectroscopy and theoretical calculations. We obtained the electronic structure and electron binding energies of the free and solvated NO3- at three detachment photon energies, 4.661, 6.424, and 7.866 eV. The ground and two low-lying electronic excited states of the NO3 radical (X (2)A(2)('),A E-2('),B E-2(')) were observed at the 6.424 and 7.866 eV photon energies. The photoelectron spectra of the solvated nitrate complexes are similar to that of the bare NO3-, except that they become broadened and diffuse due to the solvation. The spectrum of NO3-(H3O)(3) showed a resolved vibrational progression of the N-O symmetric stretching (1000 cm(-1)), suggesting the cluster possesses a high symmetry. NO3- and NO3 were calculated at various levels of theory. Based on the good agreement between density functional theory calculations and experiment for NO3- and NO3, we carried out systematic calculations for NO3-(H2O)(n) (n=1-6) using primarily density function theory methods. The calculations indicate that NO3-(H2O)(n) (n=1-3) are all planar, with the first three H2O forming the first solvation shell around NO3-, giving rise to a highly symmetric C-3h NO3-(H2O)(3). The next three waters form a second solvation shell without direct contact with NO3-. The C-3h NO3-(H2O)(3) solvation structure was observed to be rather robust and largely preserved in the larger clusters. (C) 2002 American Institute of Physics. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Genentech Inc, San Francisco, CA 94080 USA. RP Wang, XB (reprint author), Washington State Univ, Dept Phys, Richland, WA 99352 USA. NR 50 TC 60 Z9 61 U1 0 U2 19 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2002 VL 116 IS 2 BP 561 EP 570 DI 10.1063/1.1427067 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 505QH UT WOS:000172926700012 ER PT J AU Roy, S Lucht, RP Reichardt, TA AF Roy, S Lucht, RP Reichardt, TA TI Polarization spectroscopy using short-pulse lasers: Theoretical analysis SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DEGENERATE 4-WAVE-MIXING SPECTROSCOPY; QUANTITATIVE CONCENTRATION MEASUREMENTS; ATMOSPHERIC-PRESSURE FLAMES; PICOSECOND LASER; INDUCED FLUORESCENCE; OH; SATURATION AB The physics of short-pulse polarization spectroscopy (PS) and the diagnostic potential for quantitative measurements of species concentration are investigated by direct numerical integration (DNI) of the time-dependent density matrix equations for a multistate system. The effects of laser power, collision rates, and Doppler broadening on the short-pulse PS signal generation process are investigated by systematically varying these parameters in the numerical calculations. It is found that the use of a short-pulse laser (laser pulse width tau (L)< characteristic collision time tau (C)) significantly decreases the collision-rate dependence of the PS signal compared to the long-pulse laser case (tau (L)> tau (C)), even for a nonsaturating pump beam. For a saturating pump beam, the short-pulse PS signal is found to be nearly independent of collision rate. Increasing the collision rate by a factor of 100 (from 10(8) to 10(10) s(-1)), the calculated PS signal strength decreases by only a factor of 2 for a 100-ps pump laser at high intensity. This insensitivity of the PS signal to the collision rate in the medium enhances greatly the potential for quantitative application of the technique for concentration measurements in reacting flows. The underlying physics of the short-pulse PS is explored by studying the effects of collision rate, Doppler broadening, and the pump laser intensity on the temporal profile of the Zeeman state populations and the coherences between the Zeeman states. (C) 2002 American Institute of Physics. C1 Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Lucht, RP (reprint author), Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. NR 25 TC 16 Z9 16 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2002 VL 116 IS 2 BP 571 EP 580 DI 10.1063/1.1423949 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 505QH UT WOS:000172926700013 ER PT J AU Tschumper, GS Leininger, ML Hoffman, BC Valeev, EF Schaefer, HF Quack, M AF Tschumper, GS Leininger, ML Hoffman, BC Valeev, EF Schaefer, HF Quack, M TI Anchoring the water dimer potential energy surface with explicitly correlated computations and focal point analyses SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HYDROGEN-FLUORIDE DIMER; GAUSSIAN-BASIS SETS; COUPLED-CLUSTER CALCULATIONS; AB-INITIO CALCULATIONS; ELECTRON CORRELATION; WAVE-FUNCTIONS; MOLECULAR CALCULATIONS; DISSOCIATION-ENERGIES; SYSTEMATIC SEQUENCES; PERTURBATION-THEORY AB Ten stationary points on the water dimer potential energy surface have been characterized with the coupled-cluster technique which includes all single and double excitations as well as a perturbative approximation of triple excitations [CCSD(T)]. Using a triple-zeta basis set with two sets of polarization functions augmented with higher angular momentum and diffuse functions [TZ2P(f,d)+dif], the fully optimized geometries and harmonic vibrational frequencies of these ten stationary points were determined at the CCSD(T) theoretical level. In agreement with other ab initio investigations, only one of these ten stationary points is a true minimum. Of the other nine structures, three are transition structures, and the remaining are higher order saddle points. These high-level ab initio results indicate that the lowest lying transition state involved in hydrogen interchange is chiral, of C-1 symmetry rather than C-s as suggested by recently developed 6D potential energy surfaces. The one- and n-particle limits of the electronic energies of these ten stationary points were probed by systematic variation of the atomic orbital basis sets and the treatment of electron correlation within the framework of the focal-point analysis of Allen and co-workers. The one-particle limit was approached via extrapolation of electronic energies computed with the augmented correlation consistent basis sets (aug-cc-pVXZ, X=D-6), and, independently, by estimating the basis set incompleteness effect with the explicitly-correlated second-order Moller-Plesset method (MP2-R12). Electron correlation was evaluated at levels as high as the Brueckner coupled cluster method with double excitations and perturbatively treated triple and quadruple excitations [BD(TQ)]. Core correlation and relativistic effects were also assessed. Consideration of the aforementioned electronic effects as well as basis set superposition error leads to an estimate of 21.0 kJ mol(-1) for the electronic dissociation energy of (H2O)(2). (C) 2002 American Institute of Physics. C1 Univ Georgia, Ctr Computat Quantum Chem, Athens, GA 30602 USA. Univ Mississippi, Dept Chem & Biochem, University, MS 38677 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Johns Hopkins Univ, Dept Chem, Baltimore, MD 21218 USA. Georgia Inst Technol, Sch Chem & Biochem, Ctr Computat Mol Sci & Technol, Atlanta, GA 30332 USA. ETH Honggerberg, Phys Chem Lab, HCI, CH-8093 Zurich, Switzerland. RP Schaefer, HF (reprint author), Univ Georgia, Ctr Computat Quantum Chem, Athens, GA 30602 USA. RI Valeyev, Eduard/A-5313-2009; Quack, Martin/H-4457-2016; OI Valeyev, Eduard/0000-0001-9923-6256; Tschumper, Gregory/0000-0002-3933-2200 NR 89 TC 201 Z9 201 U1 1 U2 27 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2002 VL 116 IS 2 BP 690 EP 701 DI 10.1063/1.1408302 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 505QH UT WOS:000172926700023 ER PT J AU Lee, KYC Gopal, A von Nahmen, A Zasadzinski, JA Majewski, J Smith, GS Howes, PB Kjaer, K AF Lee, KYC Gopal, A von Nahmen, A Zasadzinski, JA Majewski, J Smith, GS Howes, PB Kjaer, K TI Influence of palmitic acid and hexadecanol on the phase transition temperature and molecular packing of dipalmitoylphosphatidyl-choline monolayers at the air-water interface SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID X-RAY-DIFFRACTION; PROTEIN SP-B; PULMONARY SURFACTANT; PHOSPHOLIPID MONOLAYERS; LUNG SURFACTANT; FATTY-ACID; LANGMUIR MONOLAYERS; LIPID MONOLAYERS; BEHAVIOR; FLUORESCENCE AB Palmitic acid (PA) and 1-hexadecanol (HD) strongly affect the phase transition temperature and molecular packing of dipalmitoylphosphatidylcholine (DPPC) monolayers at the air-water interface. The phase behavior and morphology of mixed DPPC/PA as well as DPPC/HD monolayers were determined by pressure-area-isotherms and fluorescence microscopy. The molecular organization was probed by synchrotron grazing incidence x-ray diffraction using a liquid surface diffractometer. Addition of PA or HD to DPPC monolayers increases the temperature of the liquid-expanded to condensed phase transition. X-ray diffraction shows that DPPC forms mixed crystals both with PA and HD over a wide range of mixing ratios. At a surface pressure (pi) of 40 mN/m, increasing the amount of the single chain surfactant leads to a reduction in tilt angle of the aliphatic chains from nearly 30 degrees for pure DPPC to almost 0 degrees in a 1:1 molar ratio of DPPC and PA or HD. At this composition we also find closest packing of the aliphatic chains. Further increase of the amount of PA or HD does not change the lattice or the tilt. (C) 2002 American Institute of Physics. C1 Univ Chicago, Dept Chem, Chicago, IL 60637 USA. Univ Chicago, Inst Biophys Dynam, Chicago, IL 60637 USA. Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA. Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, LANSCE 12, Los Alamos, NM 87545 USA. Riso Natl Lab, Dept Solid State Phys, DK-4000 Roskilde, Denmark. RP Lee, KYC (reprint author), Univ Chicago, Dept Chem, 5735 S Ellis Ave, Chicago, IL 60637 USA. RI Gopal, Ajaykumar/C-8886-2009; Lujan Center, LANL/G-4896-2012 OI Gopal, Ajaykumar/0000-0003-4632-4863; NR 55 TC 87 Z9 87 U1 2 U2 33 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2002 VL 116 IS 2 BP 774 EP 783 DI 10.1063/1.1420730 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 505QH UT WOS:000172926700032 ER PT J AU Yang, BS Lal, J Mihailescu, M Monkenbusch, M Richter, D Huang, JS Kohn, J Russel, WB Prud'homme, RK AF Yang, BS Lal, J Mihailescu, M Monkenbusch, M Richter, D Huang, JS Kohn, J Russel, WB Prud'homme, RK TI Neutron spin-echo study of dynamics of hydrophobically modified polymer-doped surfactant bilayers SO LANGMUIR LA English DT Article ID MOLECULAR-WEIGHT SAMPLE; ASSOCIATIVE BEHAVIOR; DILUTE LAMELLAR; PHASES; MEMBRANES; SYSTEM; PEG; FLUCTUATIONS; FLEXIBILITY; MODEL AB We characterize the effect of adsorbed hydrophobically modified polymers (hm-polymers) on the dynamics of surfactant bilayers by small-angle neutron scattering and neutron spin-echo spectroscopy. Two kinds of hm-polymers, (a) hydrophobically modified poly(acrylate) with tetradecyl (C(14)) sidegroups randomly grafted to the poly(acrylate) backbone and (b) poly(PEG(6k)-lysine-stearylamide) with equally spaced hydrophobes, are added to bilayers of penta(ethylene glycol) dodecyl ether (C(12)E(5)) and hexanol. Both bare and polymer-doped membranes exhibit a stretched exponential relaxation in the form of S((q) over bar ,t) 2; S((q) over bar) exp[-(Gamma(q)t)(2/3)], where S(q) is the static structure factor and Gamma(q) is the relaxation rate. The relaxation rate depends subtly on the surface coverage of polymer. At high surface coverage, polymer slows down the relaxation by 20%, whereas at low surface coverage, polymer enhances the rate relative to that of the bare membranes. Hindered flow of solvent through the adsorbed polymer layer at high coverage appears to explain the retardation. The faster dynamics at low polymer coverage may be due to stiffening of the membrane or lateral diffusion of the dilute adsorbed polymer chains. C1 Princeton Univ, Dept Chem Engn, Princeton, NJ 08544 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. Rutgers State Univ, Dept Chem, Piscataway, NJ 08854 USA. RP Russel, WB (reprint author), Princeton Univ, Dept Chem Engn, Princeton, NJ 08544 USA. RI Richter, Dieter/H-3701-2013 OI Richter, Dieter/0000-0003-0719-8470 NR 41 TC 16 Z9 17 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 8 PY 2002 VL 18 IS 1 BP 6 EP 13 DI 10.1021/la010646k PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 512UD UT WOS:000173341200002 ER PT J AU Chiarelli, PA Johal, MS Holmes, DJ Casson, JL Robinson, JM Wang, HL AF Chiarelli, PA Johal, MS Holmes, DJ Casson, JL Robinson, JM Wang, HL TI Polyelectrolyte spin-assembly SO LANGMUIR LA English DT Article ID LIGHT-EMITTING-DIODES; THIN-FILMS; POLYMER-FILMS; SOLVENT; THICKNESS; EVAPORATION; MULTILAYERS; AZOBENZENE; ADSORPTION; DEPOSITION AB Polyelectrolyte thin films composed of alternating layers were spin-assembled by sequentially dropping cationic and anionic aqueous solutions onto a spinning substrate. In this work, we show the applicability of our technique to multiple systems and present two methods for producing linear film growth. The polycations used were PEI (poly(ethylenimine), PDDA (poly(diallyldimethylammonium chloride), PAH (poly(allylamine hydrochloride), and two poly(propylenimine) dendrimers (generations 3.0 and 4.0). The polyanions used were PAZO (poly [1-[4-(3-carboxy-4-hydroxy-phenylazo)benzene sulfonamidol-1,2-ethanediyl, sodium salt]), PSS (poly(styrenesulfonate)), and PAA (poly(acrylic acid)). Layer thicknesses for all systems were determined using single-wavelength ellipsometry. UV-vis spectroscopy was used to measure deposition amounts in films containing the chromophoric polyanions PAZO and PSS. We demonstrate the ability to spin-assemble multilayered thin films up to 50 bilayers with linear increases in deposition amount between bilayers. Additionally, we show that layers of a single polyelectrolyte species can be spin-assembled with multiple deposition cycles in which consistent amounts are deposited in each cycle. In a comparison of films built from two dendrimer generations, films incorporating generation 3.0 dendrimer and PAZO show signs of higher interpenetration between layers and a more collapsed film structure than films assembled from generation 4.0 dendrimer and PAZO. Our results also suggest that a substrate effect influences the packing density of the first few bilayers, eventually dissipating around a film thickness of 50-80 Angstrom. C1 Los Alamos Natl Lab, Div Biosci, Los Alamos, NM 87545 USA. Pomona Coll, Dept Chem, Claremont, CA 91711 USA. Univ S Florida, New Coll, Div Nat Sci, Sarasota, FL 34243 USA. Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP Johal, MS (reprint author), Univ S Florida, New Coll, Div Nat Sci, Sarasota, FL 34243 USA. NR 49 TC 79 Z9 80 U1 3 U2 40 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 8 PY 2002 VL 18 IS 1 BP 168 EP 173 DI 10.1021/la011333s PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 512UD UT WOS:000173341200023 ER PT J AU McCarthy, PA Huang, JY Yang, SC Wang, HL AF McCarthy, PA Huang, JY Yang, SC Wang, HL TI Synthesis and characterization of water-soluble chiral conducting polymer nanocomposites SO LANGMUIR LA English DT Article ID COUNTERION INDUCED PROCESSIBILITY; OPTICALLY-ACTIVE POLYANILINE; ACID; RECOGNITION; COLLOIDS AB We report the template-guided synthesis of water-soluble chiral conducting polymer nanocomposites. This synthetic route is facile and can be carried out on a large, scale easily. Synthesis of water-soluble polyaniline nanocomposites is achieved by careful control of experimental parameters such as acid concentration, ionic strength, monomer/template ratio, total reagent concentration, order of reagent addition, temperature, and timing. Here, we show that a chiral polyaniline nanocomposite can be synthesized by addition of a chiral inducing agent (chiral acid) prior to polymerization and that the enantioselectivity of polyaniline can be controlled by the addition of the (+) or (-) form of the chiral acid. Further, we show that varying the chiral acid and/or salt concentration has a dramatic impact on the degree of chirality in the final polymer nanocomposite. The polyaniline nanocomposites were characterized by UV-vis, infrared (IR), circular dichroism spectroscopy, and tunneling electron microscopy. IR spectra show that the polyaniline and the template are intimately mixed at the molecular level. The strong polyaniline/template interaction results in nanocomposite chirality that. is robust through repeated doping and dedoping cycles. C1 Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Mat Sci, Los Alamos, NM 87545 USA. Univ Rhode Isl, Dept Chem, Kingston, RI 02881 USA. RP Wang, HL (reprint author), Los Alamos Natl Lab, Biosci Div, MSJ586, Los Alamos, NM 87545 USA. RI Huang, Jianyu/C-5183-2008 NR 21 TC 96 Z9 98 U1 0 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 8 PY 2002 VL 18 IS 1 BP 259 EP 263 DI 10.1021/la0111093 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 512UD UT WOS:000173341200035 ER PT J AU Kiick, KL Saxon, E Tirrell, DA Bertozzi, CR AF Kiick, KL Saxon, E Tirrell, DA Bertozzi, CR TI Incorporation of azides into recombinant proteins for chemoselective modification by the Staudinger ligation SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID TRANSFER-RNA-SYNTHETASE; MOLECULAR-ORBITAL METHODS; UNNATURAL AMINO-ACIDS; ESCHERICHIA-COLI; METHIONINE ANALOGS; GENETIC-CODE; IN-VIVO; LACTONES AB The introduction of chemically unique groups into proteins by means of non-natural amino acids has numerous applications in protein engineering and functional studies. One method to achieve this involves the utilization of a non-natural amino acid by the cell's native translational apparatus. Here we demonstrate that a methionine surrogate, azidohomoalanine, is activated by the methionyl-tRNA synthetase of Escherichia coli and replaces methionine in proteins expressed in methionine-depleted bacterial cultures. We further show that proteins containing azidohomoalanine can be selectively modified in the presence of other cellular proteins by means of Staudinger ligation with triarylphosphine reagents. Incorporation of azide-functionalized amino acids into proteins in vivo provides opportunities for protein modification under native conditions and selective labeling of proteins in the intracellular environment. C1 Univ Calif Berkeley, Ctr Adv Mat, Lawrence Berkeley Natl Lab, Ctr New Direct Organ Synth,Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ctr Adv Mat, Lawrence Berkeley Natl Lab, Ctr New Direct Organ Synth,Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Massachusetts, Dept Polymer Sci & Engn, Amherst, MA 01003 USA. Univ Calif Berkeley, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. CALTECH, Div Chem & Chem Engn, Pasadena, CA 91125 USA. RP Tirrell, DA (reprint author), Univ Calif Berkeley, Ctr Adv Mat, Lawrence Berkeley Natl Lab, Ctr New Direct Organ Synth,Dept Chem, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [R01 GM058867, GM58867-01, R37 GM058867] NR 30 TC 543 Z9 551 U1 15 U2 142 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD JAN 8 PY 2002 VL 99 IS 1 BP 19 EP 24 DI 10.1073/pnas.012583299 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 510XV UT WOS:000173233300006 PM 11752401 ER PT J AU Goldhaber, M AF Goldhaber, M TI A closer look at the elementary fermions SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID WEAK-INTERACTIONS; STANDARD MODEL; SYMMETRY AB Although there have been many experimental and theoretical efforts to measure and interpret small deviations from the standard model of particle physics, the gap that the model leaves in understanding why there are only three generations of the elementary fermions, with hierarchical masses, has not received the attention it deserves. I present here an attempt to fill this gap. Although our findings are mostly only qualitative, they nevertheless may be of heuristic value. Rules concerning the elementary fermions, some previously known and some new, lead to a number of conclusions and questions that seem worth pursuing. Some clarify the standard model, and others suggest possible modifications, the implications of which are discussed. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Goldhaber, M (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM goldhaber@bnl.gov NR 28 TC 10 Z9 10 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD JAN 8 PY 2002 VL 99 IS 1 BP 33 EP 36 DI 10.1073/pnas.221582298 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 510XV UT WOS:000173233300009 PM 11773637 ER PT J AU Wu, J Walukiewicz, W Yu, KM Ager, JW Shan, W Haller, EE Miotkowski, I Ramdas, AK Miotkowska, S AF Wu, J Walukiewicz, W Yu, KM Ager, JW Shan, W Haller, EE Miotkowski, I Ramdas, AK Miotkowska, S TI Band anticrossing effects in MgyZn1-yTe1-xSex alloys SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; V SEMICONDUCTORS; II-VI; ZNTE; GAP; CATION AB The electronic structures of MgyZn1-yTe1-xSex alloys were studied by optical absorption and photoluminescence techniques under applied hydrostatic pressure. In samples with both x and y not equal0, the band gap exhibits a strongly nonlinear pressure dependence which is similar to the effects observed previously in ZnTe1-xSex and ZnTe1-xSx ternaries and that is well explained by the anticrossing interaction of the selenium localized electronic states with the conduction band of the matrix. In contrast, the pressure dependence of the band gap in MgyZn1-yTe (i.e., x=0) is not significantly changed in form from that of ZnTe; it is concluded that the effects of alloying MgTe with ZnTe can be well understood within the virtual crystal approximation. (C) 2002 American Institute of Physics. C1 Univ Calif Berkeley, Appl Sci & Technol Grad Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. OptiWork Inc, Fremont, CA 94538 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Polish Acad Sci, Inst Phys, PL-02668 Warsaw, Poland. RP Univ Calif Berkeley, Appl Sci & Technol Grad Grp, Berkeley, CA 94720 USA. EM w_walukiewicz@lbl.gov RI Yu, Kin Man/J-1399-2012; Wu, Junqiao/G-7840-2011; OI Yu, Kin Man/0000-0003-1350-9642; Wu, Junqiao/0000-0002-1498-0148; Ager, Joel/0000-0001-9334-9751 NR 20 TC 10 Z9 10 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 7 PY 2002 VL 80 IS 1 BP 34 EP 36 DI 10.1063/1.1430853 PG 3 WC Physics, Applied SC Physics GA 507LB UT WOS:000173029000012 ER PT J AU Han, DX Yue, GZ Wang, KD Baugh, J Wu, Y Xu, YQ Wang, Q AF Han, DX Yue, GZ Wang, KD Baugh, J Wu, Y Xu, YQ Wang, Q TI Nanovoid-related large redshift of photoluminescence peak energy in hydrogenated amorphous silicon SO APPLIED PHYSICS LETTERS LA English DT Article ID SI-H AB A large redshift of the photoluminescence (PL) peak energy is found in hydrogenated amorphous silicon films prepared by hot-wire chemical-vapor deposition with a high-growth rate greater than or equal to 50 Angstrom /s. The PL intensity is as high as that in the standard film and its temperature dependence shows thermalization behavior. The origin of the redshift is clarified by employing H-1 nuclear magnetic resonance and mass density measurements. A similar to2% volume fraction of tube-like nanoscale voids is identified. The long spin-lattice relaxation time of H-2 in the nanovoids implies a negligible density of silicon dangling bonds on the nanovoid surfaces. We suggest that highly strained bonds on these surfaces form broad conduction-band tail states that are responsible for the PL redshift. (C) 2002 American Institute of Physics. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Han, DX (reprint author), Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. RI Baugh, Jonathan/F-3879-2011 NR 11 TC 9 Z9 9 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 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 7 PY 2002 VL 80 IS 1 BP 40 EP 42 DI 10.1063/1.1431396 PG 3 WC Physics, Applied SC Physics GA 507LB UT WOS:000173029000014 ER PT J AU Kong, J Cao, J Dai, HJ Anderson, E AF Kong, J Cao, J Dai, HJ Anderson, E TI Chemical profiling of single nanotubes: Intramolecular p-n-p junctions and on-tube single-electron transistors SO APPLIED PHYSICS LETTERS LA English DT Article ID WALLED CARBON NANOTUBES; DEVICES AB Electrical transport properties of intramolecular p-n-p junctions formed on individual semiconducting carbon nanotubes are reported. Chemical dopant "profiling" along the length of a nanotube divides the nanotube into two p-doped sections and a central n-doped section. The double p-n junctions formed on the nanotube dictate the electrical characteristics of the system. Well-defined and highly reproducible single-electron transistors with much smaller size than the geometrical length of the nanotube are obtained. (C) 2002 American Institute of Physics. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Kong, J (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94305 USA. NR 16 TC 89 Z9 92 U1 2 U2 15 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 7 PY 2002 VL 80 IS 1 BP 73 EP 75 DI 10.1063/1.1431402 PG 3 WC Physics, Applied SC Physics GA 507LB UT WOS:000173029000025 ER PT J AU Norton, DP Pearton, SJ Christen, HM Budai, JD AF Norton, DP Pearton, SJ Christen, HM Budai, JD TI Hydrogen-assisted pulsed-laser deposition of epitaxial CeO2 films on (001)InP SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS; GROWTH; OXIDE; MGO; SILICON; SI(100); GAAS AB We report on the growth of epitaxial CeO2 on (001) InP using hydrogen-assisted pulsed-laser deposition. Epitaxy is achieved via laser ablation of a CeO2 target in the presence of molecular hydrogen that is introduced during nucleation to reduce native In2O3 from the InP surface. X-ray diffraction scans confirm a cube-on-cube epitaxial relationship between the oxide film and the InP substrate. Rapid heating to the deposition temperature proved important in avoiding significant decomposition of the InP surface prior to film growth. This result should enable the integration of electronic oxide functionality with InP-based semiconductor technologies, and provide a means to explore InP metal-oxide-semiconductor field-effect transistor structures. (C) 2002 American Institute of Physics. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Norton, DP (reprint author), Univ Florida, Dept Mat Sci & Engn, POB 116400,Rhines Hall, Gainesville, FL 32611 USA. RI Schaff, William/B-5839-2009; Christen, Hans/H-6551-2013; Budai, John/R-9276-2016 OI Christen, Hans/0000-0001-8187-7469; Budai, John/0000-0002-7444-1306 NR 24 TC 6 Z9 6 U1 2 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 7 PY 2002 VL 80 IS 1 BP 106 EP 108 DI 10.1063/1.1431696 PG 3 WC Physics, Applied SC Physics GA 507LB UT WOS:000173029000036 ER PT J AU Henneman, AA Boer, D Mulders, PJ AF Henneman, AA Boer, D Mulders, PJ TI Evolution of transverse momentum dependent distribution and fragmentation functions SO NUCLEAR PHYSICS B LA English DT Article ID DEEP-INELASTIC-SCATTERING; SPIN PRODUCTION ASYMMETRIES; STRUCTURE-FUNCTION G2(X; HIGHER-TWIST EVOLUTION; DRELL-YAN PROCESS; N-C LIMIT; Q(2) EVOLUTION; E(+)E(-) ANNIHILATION; PARTON DISTRIBUTIONS; QUARK POLARIZATION AB We use Lorentz invariance and the QCD equations of motion to study the evolution of functions that appear at leading order in a I / Q expansion in azimuthal asymmetries. This includes the evolution equation of the Collins fragmentation function. The moments of these functions are matrix elements of known twist two and twist three operators. We present the evolution in the large N-c limit, restricting to non-singlet for the chiral-even functions. (C) 2002 Published by Elsevier Science B.V. C1 Vrije Univ Amsterdam, Div Phys & Astron, NL-1081 HV Amsterdam, Netherlands. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Henneman, AA (reprint author), Vrije Univ Amsterdam, Div Phys & Astron, De Boelelaan 1081, NL-1081 HV Amsterdam, Netherlands. RI Boer, Daniel/B-3493-2015; OI Boer, Daniel/0000-0003-0985-4662; Mulders, Piet/0000-0001-7678-6917 NR 62 TC 35 Z9 35 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD JAN 7 PY 2002 VL 620 IS 1-2 BP 331 EP 350 DI 10.1016/S0550-3213(01)00557-0 PG 20 WC Physics, Particles & Fields SC Physics GA 509CF UT WOS:000173126800013 ER PT J AU Gordon, JC Giesbrecht, GR Brady, JT Clark, DL Keogh, DW Scott, BL Watkin, JG AF Gordon, JC Giesbrecht, GR Brady, JT Clark, DL Keogh, DW Scott, BL Watkin, JG TI Observation of a significantly reduced (1)J(C-H) coupling constant in an agostic f-element complex: X-ray crystal structure of (ArO)Sm[(mu-OAr)(mu-Me)AlMe2](2) (Ar=2,6-i-Pr2C6H3) SO ORGANOMETALLICS LA English DT Article ID ANSA-LANTHANIDOCENE COMPLEXES; LN = LA; REACTIVITY; CH(SIME3)2; CHEMISTRY; LIGANDS; YTTRIUM; SM; TETRAHYDROFURAN; HYDROCARBYLS AB Reaction of [Sm(OAr)(3)](2) with 4 equiv of trimethylaluminum leads to formation of the bis-trimethylaluminum adduct (ArO)Sm[(mu-OAr)(mu-Me)AlMe2](2), which exhibits very short Sm-C(bridging) distances of 2.620(5) and 2.632(5) Angstrom. A reduced (1)J(C-H) coupling constant of 106 Hz and a low nu(C-H) stretch in the solution and solid-state IR spectrum are indicative of a strong agostic Sm...H-C interaction in solution. C1 Los Alamos Natl Lab, Chem Div C, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Nucl Mat Technol Div, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Glenn T Seaborg Inst Transactinium Sci, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Chem Div C, POB 1663, Los Alamos, NM 87545 USA. RI Clark, David/A-9729-2011; Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 38 TC 29 Z9 29 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 EI 1520-6041 J9 ORGANOMETALLICS JI Organometallics PD JAN 7 PY 2002 VL 21 IS 1 BP 127 EP 131 DI 10.1021/om0106251 PG 5 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 510VF UT WOS:000173227400018 ER PT J AU Barnes, MD Mahurin, SM Mehta, A Sumpter, BG Noid, DW AF Barnes, MD Mahurin, SM Mehta, A Sumpter, BG Noid, DW TI Three-dimensional photonic "molecules" from sequentially attached polymer-blend microparticles SO PHYSICAL REVIEW LETTERS LA English DT Article ID SIZE; PARTICLE; BEHAVIOR; MODES AB We report the observation of 3D linear or branched chains of polymer-blend microspheres generated from liquid droplets of solution where the modified surface structure of the polymer composite results in highly robust interparticle bonds. Using a linear quadrupole to precisely position particles in space, we are able to take advantage of this novel material property to actively assemble particles in programmable three-dimensional architectures. The robust interlocking nature of interparticle linkage gives rise to strongly coupled morphology-dependent resonances in bisphere and trisphere systems. suggesting the possibility of three-dimensional photonic "molecules" and microscale optical manipulation applications. 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. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 18 TC 24 Z9 24 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 7 PY 2002 VL 88 IS 1 AR 015508 DI 10.1103/PhysRevLett.88.015508 PG 4 WC Physics, Multidisciplinary SC Physics GA 509BQ UT WOS:000173124800044 PM 11800967 ER PT J AU Carter, TA Ji, H Trintchouk, F Yamada, M Kulsrud, RM AF Carter, TA Ji, H Trintchouk, F Yamada, M Kulsrud, RM TI Measurement of lower-hybrid drift turbulence in a reconnecting current sheet SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLLISIONLESS MAGNETIC RECONNECTION; FIELD LINE RECONNECTION; INSTABILITY; PLASMA; MODEL; ONSET AB We present a detailed study of fluctuations in a laboratory current sheet undergoing magnetic reconnection. The measurements reveal the presence of lower-hybrid-frequency-range fluctuations on the edge of current sheets produced in the magnetic reconnection experiment (MRX). The measured fluctuation characteristics are consistent with theoretical predictions for the lower-hybrid drift instability (LHDI). Our observations suggest that the LHDI turbulence alone cannot explain the observed fast reconnection rate in MRX. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Carter, TA (reprint author), Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. RI Carter, Troy/E-7090-2010; Yamada, Masaaki/D-7824-2015 OI Carter, Troy/0000-0002-5741-0495; Yamada, Masaaki/0000-0003-4996-1649 NR 15 TC 50 Z9 50 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 7 PY 2002 VL 88 IS 1 AR 015001 DI 10.1103/PhysRevLett.88.015001 PG 4 WC Physics, Multidisciplinary SC Physics GA 509BQ UT WOS:000173124800035 PM 11800958 ER PT J AU Erdin, S Lyuksyutov, IF Pokrovsky, VL Vinokur, VM AF Erdin, S Lyuksyutov, IF Pokrovsky, VL Vinokur, VM TI Topological textures in a ferromagnet-superconductor bilayer SO PHYSICAL REVIEW LETTERS LA English DT Article ID REGULAR ARRAY; MAGNETIC DOTS; FILMS; LATTICES AB The homogeneous state of a ferromagnet-superconductor bilayer (FSB) with the magnetization perpendicular to the layer can be unstable with respect to the formation of vortices in the superconducting layer. The developing topological instability in the FSB leads to formation of domains in which the direction of the magnetization in the magnetic film and the direction of vorticity in the superconducting film alternate together. This is a new, combined topological structure, which does not appear in isolated layers. Equilibrium domains can appear in the FSB even if the single magnetic film is in a monodomain state. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. LD Landau Theoret Phys Inst, Moscow, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. Inst Phys, UA-252028 Kiev, Ukraine. RP Erdin, S (reprint author), Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. RI Erdin, Serkan/B-4988-2008 OI Erdin, Serkan/0000-0001-6587-2625 NR 24 TC 60 Z9 61 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 7 PY 2002 VL 88 IS 1 AR 017001 DI 10.1103/PhysRevLett.88.017001 PG 4 WC Physics, Multidisciplinary SC Physics GA 509BQ UT WOS:000173124800056 PM 11800979 ER PT J AU Manley, DM Abaev, VV Allgower, CE Bekrenev, V Briscoe, WJ Clajus, M Comfort, JR Craig, K Grosnick, D Isenhower, D Knecht, N Koetke, DD Kulbardis, AA Kozlenko, NG Kruglov, S Lolos, G Lopatin, IV Manweiler, R Marusic, A McDonald, S Nefkens, BMK Olmsted, J Papandreou, Z Peaslee, DC Phaisangittisakul, N Prakhov, S Price, JW Ramirez, AF Sadler, M Shafi, A Spinka, H Stanislaus, TDS Starostin, A Staudenmaier, HM Strakovsky, II Supek, I Tippens, WB AF Manley, DM Abaev, VV Allgower, CE Bekrenev, V Briscoe, WJ Clajus, M Comfort, JR Craig, K Grosnick, D Isenhower, D Knecht, N Koetke, DD Kulbardis, AA Kozlenko, NG Kruglov, S Lolos, G Lopatin, IV Manweiler, R Marusic, A McDonald, S Nefkens, BMK Olmsted, J Papandreou, Z Peaslee, DC Phaisangittisakul, N Prakhov, S Price, JW Ramirez, AF Sadler, M Shafi, A Spinka, H Stanislaus, TDS Starostin, A Staudenmaier, HM Strakovsky, II Supek, I Tippens, WB CA Crystal Ball Collaboration TI Properties of the Lambda(1670)1/2(-) resonance SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEAR-THRESHOLD PHOTOPRODUCTION; PARTIAL-WAVE ANALYSIS; ETA-PHOTOPRODUCTION; KBARN INTERACTIONS; QUARK-MODEL; CHANNEL; MESONS; REGION; SCATTERING; AMPLITUDES AB Recently the Crystal Ball Collaboration measured precise new data for the near-threshold reaction K- p --> etaLambda, which is dominated by formation of the Lambda(1670)1(-)/2. In this Letter, we present results of a unitary, multichannel analysis that incorporates the new Crystal Ball data. For our preferred fit, we obtain mass M = 1673 +/- 2 MeV, width Gamma = 23 +/- 6 MeV, and elasticity x = 0.37 +/- 0.07. This elasticity is significantly larger than previously recognized. Resonance parameters of our preferred fit are in striking agreement with the quark-model predictions of Koniuk and Isgur. C1 Kent State Univ, Kent, OH 44242 USA. Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. George Washington Univ, Washington, DC 20052 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Arizona State Univ, Tempe, AZ 85287 USA. Valparaiso Univ, Valparaiso, IN 46383 USA. Abilene Christian Univ, Abilene, TX 79699 USA. Univ Regina, Regina, SK S4S 0A2, Canada. Univ Maryland, College Pk, MD 20742 USA. Univ Karlsruhe, D-76128 Karlsruhe, Germany. Rudjer Boskovic Inst, Zagreb 10002, Croatia. RP Manley, DM (reprint author), Kent State Univ, Kent, OH 44242 USA. NR 30 TC 10 Z9 10 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 7 PY 2002 VL 88 IS 1 AR 012002 DI 10.1103/PhysRevLett.88.012002 PG 4 WC Physics, Multidisciplinary SC Physics GA 509BQ UT WOS:000173124800013 ER PT J AU Munkholm, A Streiffer, SK Murty, MVR Eastman, JA Thompson, C Auciello, O Thompson, L Moore, JF Stephenson, GB AF Munkholm, A Streiffer, SK Murty, MVR Eastman, JA Thompson, C Auciello, O Thompson, L Moore, JF Stephenson, GB TI Antiferrodistortive reconstruction of the PbTiO3(001) surface SO PHYSICAL REVIEW LETTERS LA English DT Article ID AB-INITIO; RELAXATION; SRTIO3; BATIO3; DYNAMICS; SRO AB We present in situ x-ray scattering measurements of the surface structures of PbTiO3 (001) in equilibrium with PbO vapor. At 875 to 1025 K, a reconstruction having c(2 x 2) symmetry is present under most conditions, while a 1 x 6 reconstruction occurs under PbO-poor conditions. The atomic structure of the c(2 x 2) phase is found to consist of a single layer of an antiferrodistortive structure with oxygen cages counter-rotated by 10degrees about the titanium ions. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. RP Munkholm, A (reprint author), Lumileds Lighting, 370 W Trimble Rd, San Jose, CA 95131 USA. RI Streiffer, Stephen/A-1756-2009; Eastman, Jeffrey/E-4380-2011; OI Thompson, Carol/0000-0003-3832-4855 NR 28 TC 40 Z9 41 U1 2 U2 24 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 7 PY 2002 VL 88 IS 1 AR 016101 DI 10.1103/PhysRevLett.88.016101 PG 4 WC Physics, Multidisciplinary SC Physics GA 509BQ UT WOS:000173124800046 PM 11800969 ER PT J AU Ollivier, H Zurek, WH AF Ollivier, H Zurek, WH TI Quantum discord: A measure of the quantumness of correlations SO PHYSICAL REVIEW LETTERS LA English DT Article ID ENTROPY; DECOHERENCE; INFORMATION AB Two classically identical expressions for the mutual information generally differ when the systems involved are quantum. This difference defines the quantum discord. It can be used as a measure of the quantumness of correlations. Separability of the density matrix describing a pair of systems does not guarantee vanishing of the discord, thus showing that absence of entanglement does not imply classicality. We relate this to the quantum superposition principle, and consider the vanishing of discord as a criterion for the preferred effectively classical states of a system, i.e., the pointer states. C1 Los Alamos Natl Lab, Theoret Div T 6, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Theoret Div T 6, MS B288, Los Alamos, NM 87545 USA. NR 18 TC 1540 Z9 1587 U1 10 U2 84 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 7 PY 2002 VL 88 IS 1 AR 017901 DI 10.1103/PhysRevLett.88.017901 PG 4 WC Physics, Multidisciplinary SC Physics GA 509BQ UT WOS:000173124800063 PM 11800986 ER PT J AU Yu, HB Jiang, CS Ebert, P Wang, XD White, JM Niu, Q Zhang, ZY Shih, CK AF Yu, HB Jiang, CS Ebert, P Wang, XD White, JM Niu, Q Zhang, ZY Shih, CK TI Quantitative determination of the metastability of flat Ag overlayers on GaAs(110) SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM-WELL STATES; THIN-FILM; GROWTH; ISLANDS; PB AB Atomically flat ultrathin Ag films on GaAs(I 10) can be formed through a kinetic pathway. However, such films are metastable and will transform to 3D islands upon high temperature annealing. Using scanning tunneling microscopy, we have measured quantitatively the layer-resolved metastability of flat Ag overlayers as they evolve toward their stable state, and deduced the corresponding kinetic barrier the system has to overcome in reaching the stable state. These results indicate that the metastability of the Ag overlayer is defined by the quantum nature of the conduction electrons confined within the overlayer. C1 Univ Texas, Dept Phys, Austin, TX 78712 USA. Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA. Univ Texas, Texas Mat Inst, Austin, TX 78712 USA. Univ Texas, Ctr Nano & Mol Sci & Technol, Austin, TX 78712 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Yu, HB (reprint author), Univ Texas, Dept Phys, Austin, TX 78712 USA. RI Yu, hongbin/G-3265-2010; jiang, chun-sheng/F-7839-2012; Niu, Qian/G-9908-2013 NR 24 TC 33 Z9 34 U1 3 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 7 PY 2002 VL 88 IS 1 AR 016102 DI 10.1103/PhysRevLett.88.016102 PG 4 WC Physics, Multidisciplinary SC Physics GA 509BQ UT WOS:000173124800047 PM 11800970 ER PT J AU Stewart, RD Wilson, WE McDonald, JC Strom, DJ AF Stewart, RD Wilson, WE McDonald, JC Strom, DJ TI Microdosimetric properties of ionizing electrons in water: a test of the PENELOPE code system SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID MONTE-CARLO-SIMULATION; C3H 10T(1)/(2) CELLS; RADIATION ONCOGENESIS; LIQUID WATER; BYSTANDER; TRANSFORMATION; DISTRIBUTIONS; IRRADIATION; MICROBEAM; ALGORITHM AB The ability to simulate the tortuous path of very low-energy electrons in condensed matter is important for a variety of applications in radiobiology. Event-by-event Monte Carlo codes such as OREC, MOCA and PITS represent the preferred method of computing distributions of microdosimetric quantities. However, event-by-event Monte Carlo is computationally expensive, and the cross sections needed to transport simulations to this level of detail are usually only available for water. In the recently developed PENELOPE code system, 'hard' electron and positron interactions are simulated in a detailed way while,'soft' interactions are treated using multiple scattering theory. Using this mixed simulation algorithm, electrons and positrons can be transported down to energies as low as 100eV. To our knowledge, PENELOPE is the first widely available, general purpose Monte Carlo code system capable of transporting electrons and positrons in arbitrary media down to such low energies. The ability to transport electrons and positrons to such low energies opens up the possibility of using a general purpose Monte Carlo code system for microdosimetry. This paper presents the results of a code intercomparison study designed to test the applicability of the PENELOPE code system for microdosimetry applications. For sites comparable in size to a mammalian cell or cell nucleus, single-event distributions, site-hit probabilities and the frequency-mean specific energy per event are in reasonable agreement with those predicted using event-by-event Monte Carlo. Site-hit probabilities and the mean specific energy per event can be estimated to within about 1-10% of those predicted using event-by-event Monte Carlo. However, for some combinations of site size and source-target geometry, site-hit probabilities and the mean specific energy per event may only agree to within 25-60%. The most problematic source-target geometry is one in which the emitted electrons are very close to the tally site (e.g., a point source on the surface of it cell). Although event-by-event Monte Carlo will continue to be the method of choice for microdosimetry, PENELOPE is a useful, computationally efficient tool for some classes of microdosimetry problem. PENELOPE may prove particularly Useful for applications that involve radiation transport through materials other than water or for applications that are too computationally intensive for event-by-event Monte Carlo, such as in vivo microdosimetry of spatially complex distributions Of radioisotopes inside the human body. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Washington State Univ Tri Cities, Richland, WA 99352 USA. RP Stewart, RD (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM trebor@pnl.gov RI Stewart, Rob/A-2511-2009; Stewart, Robert/A-3609-2013 OI Stewart, Robert/0000-0001-5946-0595 NR 31 TC 50 Z9 52 U1 1 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD JAN 7 PY 2002 VL 47 IS 1 BP 79 EP 88 DI 10.1088/0031-9155/47/1/306 PG 10 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 516YE UT WOS:000173583700006 PM 11814229 ER PT J AU Liu, P Lee, SH Tracy, CE Yan, YF Turner, JA AF Liu, P Lee, SH Tracy, CE Yan, YF Turner, JA TI Preparation and lithium insertion properties of mesoporous vanadium oxide SO ADVANCED MATERIALS LA English DT Article ID MOLECULAR-SIEVES; V2O5 AEROGEL; METAL-OXIDES; INTERCALATION; ELECTRODES; FILMS C1 Natl Renewable Energy Lab, Denver, CO 80210 USA. RP Liu, P (reprint author), Natl Renewable Energy Lab, Denver, CO 80210 USA. RI Lee, Sehee/A-5989-2011 NR 23 TC 116 Z9 121 U1 6 U2 65 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0935-9648 J9 ADV MATER JI Adv. Mater. PD JAN 4 PY 2002 VL 14 IS 1 BP 27 EP 30 DI 10.1002/1521-4095(20020104)14:1<27::AID-ADMA27>3.0.CO;2-6 PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 512FL UT WOS:000173310400005 ER PT J AU Shen, XJ Kwak, H Radojevic, AM Smadici, S Mocuta, D Osgood, RM AF Shen, XJ Kwak, H Radojevic, AM Smadici, S Mocuta, D Osgood, RM TI Momentum-resolved excited-electron lifetimes on stepped Cu(775) SO CHEMICAL PHYSICS LETTERS LA English DT Article ID IMAGE-POTENTIAL STATES; SURFACE-STATE; 2-PHOTON PHOTOEMISSION; INELASTIC LIFETIMES; METAL-SURFACES; RYDBERG STATES; FERMI-SURFACE; FEMTOSECOND; DYNAMICS; CU(111) AB The lifetime of n = 1 image-state electrons on stepped on Cu(7 7 5) has been measured as a function of their translational momentum, k(parallel to). At the terrace normal this lifetime is equal to that for flat Cu(1 1 1), i.e. tau = 18 +/- 2 fs. For motion parallel to the step orientation, the lifetime decreases symmetrically about k(parallel to) = 0 and the absolute values are in close agreement with that predicted by a recent many-body theory. Contrasting data for motion perpendicular to the step edges is also presented. (C) 2002 Published by Elsevier Science B.V. C1 Columbia Univ, Columbia Radiat Lab, New York, NY 10027 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Osgood, RM (reprint author), Columbia Univ, Dept Elect Engn, 1312 SW Mudd,Mailcode 4712, New York, NY 10027 USA. NR 35 TC 20 Z9 20 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 4 PY 2002 VL 351 IS 1-2 BP 1 EP 8 DI 10.1016/S0009-2614(01)01356-2 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 511RX UT WOS:000173280300001 ER PT J AU Balasubramanian, K AF Balasubramanian, K TI Relativistic computations of the electronic states of the superheavy element 114 and 114(+) (vol 341, pg 601, 2001) SO CHEMICAL PHYSICS LETTERS LA English DT Correction C1 Univ Calif Davis, Coll Engn, Dept Appl Sci, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, Mat Sci Directorate, Livermore, CA 94550 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. RP Balasubramanian, K (reprint author), Univ Calif Davis, Coll Engn, Dept Appl Sci, Hertz Hall,Bldg 661,POB 808,L-794, Livermore, CA 94550 USA. NR 3 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 4 PY 2002 VL 351 IS 1-2 BP 161 EP 162 DI 10.1016/S0009-2614(01)01265-9 PG 2 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 511RX UT WOS:000173280300025 ER PT J AU Schafer, LL Nitschke, JR Mao, SSH Liu, FQ Harder, G Haufe, M Tilley, TD AF Schafer, LL Nitschke, JR Mao, SSH Liu, FQ Harder, G Haufe, M Tilley, TD TI Zirconocene-mediated, high-yielding macrocyclizations of silyl-terminated diynes SO CHEMISTRY-A EUROPEAN JOURNAL LA English DT Article DE alkynes; cyclodimerization; cyclophanes; cyclotrimerization; macrocycles ID AGOSTIC ALKENYLZIRCONOCENE COMPLEXES; ETA-6 COORDINATION; MACROCYCLES; EFFICIENT; POLYMERS; ALKYNES; ROUTE; <2.2.2>PARACYCLOPHANE; TRANSFORMATION; RECOGNITION AB A series of silyl-terminated diynes of varying lengths and substitution patterns have been prepared. These diynes undergo zirconocene coupling with selective formation of trimeric macrocycles from linear alkynes, while nonlinear diynes give cyclodimeric products. The length of the linear diynes can be increased the preparation of macrocycles with large nanoscale cavities. Reaction of the zirconium-containing macrocycles with acid results in the synthesis of metal-free cyclophanes. All of these macrocycles were prepared in multigram quantities, in the absence of high-dilution conditions, to give products in >75% yield that are easily purified as crystalline solids. C1 Univ Calif Berkeley, Ctr New Direct Organ Synth, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Tilley, TD (reprint author), Univ Calif Berkeley, Ctr New Direct Organ Synth, Dept Chem, Berkeley, CA 94720 USA. RI Nitschke, Jonathan/A-1664-2010 OI Nitschke, Jonathan/0000-0002-4060-5122 NR 58 TC 36 Z9 36 U1 0 U2 5 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0947-6539 J9 CHEM-EUR J JI Chem.-Eur. J. PD JAN 4 PY 2002 VL 8 IS 1 BP 74 EP 83 DI 10.1002/1521-3765(20020104)8:1<74::AID-CHEM74>3.0.CO;2-P PG 10 WC Chemistry, Multidisciplinary SC Chemistry GA 511CZ UT WOS:000173248200007 PM 11826866 ER PT J AU Fritz, JS Breadmore, MC Hilder, EF Haddad, PR AF Fritz, JS Breadmore, MC Hilder, EF Haddad, PR TI Use of ionic polymers as stationary and pseudo-stationary phases in the separation of ions by capillary electrophoresis and capillary electrochromatography SO JOURNAL OF CHROMATOGRAPHY A LA English DT Review DE reviews; ion chromatography-capillary electrophoresis; electrochromatography; stationary phases, electrochromatography; capillary electrophoresis-ion chromatography; inorganic anions; organic acids; inorganic cations ID REVERSED ELECTROOSMOTIC FLOW; EXCHANGE ELECTROKINETIC CHROMATOGRAPHY; POLYETHYLENEIMINE-COATED CAPILLARY; INORGANIC ANIONS; ZONE ELECTROPHORESIS; CATIONIC POLYMERS; ELECTROLYTE-COMPOSITION; LIQUID-CHROMATOGRAPHY; SURFACTANT MIXTURES; ISOTOPIC-SEPARATION AB One of the problems with capillary electrophoresis is a lack of versatility regarding manipulation of the separation selectivity. A new and potentially universal concept is to introduce an ion-exchange component into a separation so that the migration of analyte ions is influenced by both their electrophoretic mobilities and their chromatographic properties. This may be accomplished by use of capillaries filled with or coated with solid ion-exchange polymers, or by addition of a soluble ionic polymer to the background electrolyte to create a pseudo-stationary phase. While each of these methods achieves the same result, they are not competitive, but rather complementary as the problems associated by one approach are overcome by the others. Recent highlights in the field are used to illustrate the flexibility that this approach provides to electrophoretic separation of ions. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Univ Tasmania, Australian Ctr Res Separat Sci, Hobart, Tas 7001, Australia. RP Fritz, JS (reprint author), Iowa State Univ Sci & Technol, Dept Chem, 332 Wilhelm Hall, Ames, IA 50011 USA. RI Hilder, Emily/A-1001-2009 OI Hilder, Emily/0000-0002-4444-7870 NR 55 TC 24 Z9 24 U1 2 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JAN 4 PY 2002 VL 942 IS 1-2 BP 11 EP 32 DI 10.1016/S0021-9673(01)01403-0 PG 22 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 509AA UT WOS:000173120900002 PM 11822376 ER PT J AU Feibelman, PJ AF Feibelman, PJ TI Partial dissociation of water on Ru(0001) SO SCIENCE LA English DT Article ID ABINITIO MOLECULAR-DYNAMICS; TOTAL-ENERGY CALCULATIONS; AUGMENTED-WAVE METHOD; ULTRASOFT PSEUDOPOTENTIALS; BASIS-SET; ADSORPTION; H2O; CLUSTERS; BILAYER; METALS AB Initial water deposition on the moderately reactive precious metal surface Ru(0001) has been thought to produce an ice-like bilayer. However, calculations from first principles show that the wetting layer observed on Ru(0001) cannot be formed of undissociated water molecules. An energetically favorable alternative, consistent with the remarkable observation that the wetting layer's oxygen atoms are nearly coplanar, is a half-dissociated monolayer wherein water molecules and hydroxyl fragments are hydrogen-bonded in a hexagonal structure and hydrogen atoms bind directly to the metal. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Feibelman, PJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 31 TC 352 Z9 355 U1 10 U2 73 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 4 PY 2002 VL 295 IS 5552 BP 99 EP 102 DI 10.1126/science.1065483 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 509HV UT WOS:000173143100040 PM 11778041 ER PT J AU Mukai, T Nieh, TG Kawamura, Y Inoue, A Higashi, K AF Mukai, T Nieh, TG Kawamura, Y Inoue, A Higashi, K TI Dynamic response of a Pd40Ni40P20 bulk metallic glass in tension SO SCRIPTA MATERIALIA LA English DT Article DE bulk metallic glass; dynamic tensile loading; strain rate; shear bands ID AMORPHOUS-ALLOYS; STRAIN-RATE; FRACTURE; DEFORMATION; FLOW; MECHANISMS; TEMPERATURE; STRESS AB Tensile behavior of a bulk metallic glass Pd40Ni40P20 was characterized under both quasi-static and dynamic strain rate conditions. No major difference was observed. Multiple shear bands formed in samples tested at the dynamic strain rate. However, shear band interaction appears to have an insignificant effect on the plasticity of the alloy. (C) 2002 Acta aterialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Osaka Municipal Tech Res Inst, Joto Ku, Osaka 5368553, Japan. Kumamoto Univ, Dept Mech Engn & Mat Sci, Kumamoto 8608555, Japan. Tohoku Univ, Inst Mat Res, Aoba Ku, Sendai, Miyagi 9808577, Japan. Univ Osaka Prefecture, Coll Engn, Dept Met & Mat Sci, Sakai, Osaka 5998531, Japan. RP Mukai, T (reprint author), Lawrence Livermore Natl Lab, L-369,POB 808, Livermore, CA 94551 USA. RI Nieh, Tai-Gang/G-5912-2011; Mukai, Toshiji/F-9570-2014; Inoue, Akihisa/E-5271-2015; Totsukawa, Nobuhisa/D-2028-2017 OI Nieh, Tai-Gang/0000-0002-2814-3746; Mukai, Toshiji/0000-0002-9628-5762; NR 21 TC 160 Z9 166 U1 1 U2 29 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JAN 4 PY 2002 VL 46 IS 1 BP 43 EP 47 AR PII S1359-6462(01)01193-9 DI 10.1016/S1359-6462(01)01193-9 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 547LC UT WOS:000175333000008 ER PT J AU Namilae, S Chandra, N Nieh, TG AF Namilae, S Chandra, N Nieh, TG TI Atomistic simulation of grain boundary sliding in pure and magnesium doped aluminum bicrystals SO SCRIPTA MATERIALIA LA English DT Article DE grain boundaries; computer simulation; aluminum ID SYMMETRICAL TILT; MISORIENTATION DEPENDENCE; FRACTURE-BEHAVIOR; COPPER; SEGREGATION; DEFECTS; ALLOYS; ENERGY AB Molecular dynamics and statics simulations are used to study grain boundary sliding and energy in bicrystals with symmetric tilt grain boundaries of Al and Mg doped Al. There is an increase in grain boundary energy in Al bicrystals with the presence of Mg depending on the position of Mg atom. Simulations of sliding show a clear dependence of magnitude of sliding on grain boundary energy. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Florida State Univ, Coll Engn, FAMU, Dept Engn Mech, Tallahassee, FL 32310 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Chandra, N (reprint author), Florida State Univ, Coll Engn, FAMU, Dept Engn Mech, 2525 Pottsdamer St, Tallahassee, FL 32310 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 25 TC 33 Z9 33 U1 2 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JAN 4 PY 2002 VL 46 IS 1 BP 49 EP 54 AR PII S1359-6462(01)01195-2 DI 10.1016/S1359-6462(01)01195-2 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 547LC UT WOS:000175333000009 ER PT J AU Prime, MB Hill, MR AF Prime, MB Hill, MR TI Residual stress, stress relief, and inhomogeneity in aluminum plate SO SCRIPTA MATERIALIA LA English DT Article DE cold working; mechanical properties; structural behavior; plastic anisotropy; aluminum alloy AB Through-thickness residual-stress profiles in rolled 7050-T74 aluminum plate were measured before and after stress relief by stretching (-Tx51). Measurement required adapting the crack-compliance method to measure both in-plane stress components. Unexpected features in the profiles could be explained by through-thickness yield strength variations caused by crystallographic texture. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Los Alamos Natl Lab, Engn Sci & Applicat Div, Los Alamos, NM 87545 USA. Univ Calif Davis, Dept Mech & Aeronaut Engn, Davis, CA 95616 USA. RP Prime, MB (reprint author), Los Alamos Natl Lab, Engn Sci & Applicat Div, MS P946, Los Alamos, NM 87545 USA. RI Hill, Michael/A-2525-2016; OI Hill, Michael/0000-0002-9168-211X; Prime, Michael/0000-0002-4098-5620 NR 13 TC 98 Z9 121 U1 9 U2 26 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JAN 4 PY 2002 VL 46 IS 1 BP 77 EP 82 AR PII S1359-6462(01)01201-5 DI 10.1016/S1359-6462(01)01201-5 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 547LC UT WOS:000175333000014 ER PT J AU Mel'nikov, AS Vinokur, VM AF Mel'nikov, AS Vinokur, VM TI Mesoscopic superconductor as a ballistic quantum switch SO NATURE LA English DT Article ID STATES AB Several key experiments(1-3) have revealed a rich variety of vortex structures in mesoscopic superconductors in which only a few quanta of magnetic flux are trapped: these structures are polygon-like vortex 'molecules' and multi-quanta giant vortices. Ginzburg-Landau calculations(4) confirmed second-order phase transitions between the giant vortex states and stable molecule-like configurations(5). Here we study theoretically the electronic structure and the related phase-coherent transport properties of such mesoscopic superconductor systems. The quasiparticle excitations in the vortices form coherent quantum-mechanical states that offer the possibility of controlling the phase-coherent transport through the sample by changing the number of trapped flux quanta and their configuration. The sample conductance measured in the direction of the applied magnetic field is determined by the transparency of multi-vortex configurations, which form a set of quantum channels. The transmission coefficient for each channel is controlled by multiple Andreev reflections within the vortex cores and at the sample edge. These interference phenomena result in a stepwise behaviour of the conductance as a function of the applied magnetic field, and we propose to exploit this effect to realize a vortex-based quantum switch where the magnetic field plays the role of the gate voltage. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Russian Acad Sci, Inst Phys Microstruct, Nizhnii Novgorod 603950, Russia. RP Vinokur, VM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Mel'nikov, Alexander/E-8099-2017 OI Mel'nikov, Alexander/0000-0002-4241-467X NR 13 TC 50 Z9 50 U1 0 U2 9 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 3 PY 2002 VL 415 IS 6867 BP 60 EP 62 DI 10.1038/415060a PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 507KZ UT WOS:000173028800037 PM 11780114 ER PT J AU Coyle, JE Qamar, S Rajashankar, KR Nikolov, DB AF Coyle, JE Qamar, S Rajashankar, KR Nikolov, DB TI Structure of GABARAP in two conformations: Implications for GABA(A) receptor localization and tubulin binding SO NEURON LA English DT Article ID MICROTUBULE-ASSOCIATED PROTEINS; NICOTINIC ACETYLCHOLINE-RECEPTOR; MEMBRANE-TRANSPORT MODULATOR; TUMOR-SUPPRESSOR PROTEIN; GEPHYRIN; SUBUNIT; STOICHIOMETRY; CYTOSKELETON; NSF; IDENTIFICATION AB GABARAP recognizes and binds the gamma2 subunit of the GABA(A) receptor, interacts with microtubules and the N-ethyl maleimide sensitive factor, and is proposed to function in GABA(A) receptor trafficking and postsynaptic localization. We have determined the crystal structure of human GABARAP at 1.6 Angstrom resolution. The structure comprises an N-terminal helical subdomain and a ubiquitin-like C-terminal domain. Structure-based mutational analysis demonstrates that the N-terminal subdomain is responsible for tubulin binding while the C-terminal domain contains the binding site for the GABA(A). A second GABARAP crystal form was determined at 1.9 Angstrom resolution and documents that GABARAP can self-associate in a head-to-tail manner. The structural details of this oligomerization reveal how GABARAP can both promote tubulin polymerization and facilitate GABA(A) receptor clustering. C1 Mem Sloan Kettering Canc Ctr, Cellular Biochem & Biophys Program, New York, NY 10021 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Nikolov, DB (reprint author), Mem Sloan Kettering Canc Ctr, Cellular Biochem & Biophys Program, 1275 York Ave, New York, NY 10021 USA. NR 67 TC 94 Z9 98 U1 0 U2 2 PU CELL PRESS PI CAMBRIDGE PA 1100 MASSACHUSETTS AVE,, CAMBRIDGE, MA 02138 USA SN 0896-6273 J9 NEURON JI Neuron PD JAN 3 PY 2002 VL 33 IS 1 BP 63 EP 74 DI 10.1016/S0896-6273(01)00558-X PG 12 WC Neurosciences SC Neurosciences & Neurology GA 508TT UT WOS:000173106200010 PM 11779480 ER PT J AU Chasman, RR AF Chasman, RR TI N-P pairing in nuclei SO PHYSICS LETTERS B LA English DT Article ID PROTON AB Variational wavefunctions for treating N-P pairing in the T = I and T = 0 channels are presented. Alpha-like correlations are explicitly included in the wavefunctions and arbitrary sin.-le-particle energy level spacings are allowed. A triple projection before variation procedure is used to obtain these wavefunctions. Taking a model system with equally spaced single-particle levels, several features of nuclei near the N = Z line are calculated. A new type of multiple degeneracy is found in nuclei near the N = Z line. (C) 2002 Published by Elsevier Science B.V. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. EM chasman@theory.phy.anl.gov NR 17 TC 22 Z9 22 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD JAN 3 PY 2002 VL 524 IS 1-2 BP 81 EP 86 DI 10.1016/S0370-2693(01)01364-8 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 508AX UT WOS:000173066000010 ER PT J AU Bedaque, PF AF Bedaque, PF TI Charged kaon condensation in high density quark matter SO PHYSICS LETTERS B LA English DT Article DE quark matter; superconductivity; kaon condensation ID COLOR-FLAVOR-LOCKING; SYMMETRY BREAKING; BARYON DENSITY; QCD; SUPERCONDUCTIVITY; PHASE; MASS AB We show that at asymptotically high densities the ''color-flavor-locked + neutral kaon condensate'' phase of QCD develops a charged kaon condensate through the Coleman-Weinberg mechanism. At densities achievable in neutron stars a charged kaon condensate forms only for some (natural) values of the low energy constants describing the low-lying excitations of the ground state. (C) 2002 Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Bedaque, PF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 32 TC 12 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JAN 3 PY 2002 VL 524 IS 1-2 BP 137 EP 143 DI 10.1016/S0370-2693(01)01387-9 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 508AX UT WOS:000173066000018 ER PT J AU Buzin, AI Kamasa, P Pyda, M Wunderlich, B AF Buzin, AI Kamasa, P Pyda, M Wunderlich, B TI Application of a Wollaston wired probe for quantitative thermal analysis SO THERMOCHIMICA ACTA LA English DT Article DE local microanalysis; frequency dependence; Wollaston wire probe; heat conductivity ID MICROSCOPY; CONDUCTIVITY AB In this work, we have investigated the properties of the Wollaston wire thermal resistive probe which is frequently used for microthermal analysis. Special attention was drawn to the frequency dependence of the performance of the probe. We demonstrated that at frequencies above 5 kHz, the temperature of the Wollaston wire probe becomes increasingly insensitive to modulations of the driving current. We submerged such a probe in air and a number of liquids to measure the heat conductivities by simultaneous determination of the applied power and increase in temperature. The heat conductivities were established both by application of direct current (dc) and modulated current. The advantages and disadvantages of different techniques of thermal analysis with this type of resistive probe are discussed. A method of multifrequency analysis at a fixed location for the elimination of the effects of contact area and thermal resistance is proposed for analyses in the frequency range of 10-100 Hz. Crown Copyright (C) 2002 Published by Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Buzin, Alexander/H-5482-2011 NR 19 TC 23 Z9 23 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD JAN 3 PY 2002 VL 381 IS 1 BP 9 EP 18 DI 10.1016/S0040-6031(01)00648-7 PG 10 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 509DC UT WOS:000173128800002 ER PT J AU Shevenell, L McCarthy, JF AF Shevenell, L McCarthy, JF TI Effects of precipitation events on colloids in a karst aquifer SO JOURNAL OF HYDROLOGY LA English DT Article DE colloids; karst; turbidity; Tennessee; precipitation; chemistry ID FACILITATED TRANSPORT; MOBILIZATION; FIELD; PARTICLES; MIGRATION; FRACTURE; BACTERIOPHAGE; RELEASE; TRACERS; FINES AB The effects of precipitation events on colloid mobilization were evaluated during several storms from six wells in a karstic aquifer at the Oak Ridge Y-12 Plant in eastern Tennessee (USA). Turbidity increases and rapidly recedes following rain events. Although the magnitude of the turbidity increases are relatively small (less than or equal to4.78 NTU), the increased turbidity suggests transient increases in colloid abundance during storm versus non-storm periods. During the larger storms (> 19 mm), the increased turbidity is associated with increases in pH, total organic carbon (TOC) and temperature, and with decreases in dissolved oxygen (DO). These larger storms result in flushing of a greater proportion of higher pH, TOC (and lower DO) soil or matrix waters into the fractures and conduits than occurs during smaller storms. Smaller storms also result in increases in turbidity, but show increases in DO and decreases in pH reflecting less influence on the water chemistry from the longer residence time epikarst or and matrix waters, and greater impact from the more dilute, newly recharged waters. Due to the complexity of karst flow and temporal variations in flow and chemistry, controls on turbidity are not consistent through time and space at the wells. During smaller storms. recharge by lower ionic strength waters may promote colloid release and thus contribute to observed increases in turbidity. During larger storms, elevated turbidity may be more related to pH increases resulting from greater influx of matrix and soil waters into fractures and conduits. Chemical factors alone cannot account for the changes in turbidity observed during the various storms. Because of the complicated nature of flow and particle transport in karst aquifers, the presence of colloids during precipitation events is dictated by a complex interplay of chemical reactions and the effects of physical perturbations due to increased flow through the conduits and fractures. Simple trends in water quality parameters could not be identified, and broad generalizations cannot easily be made in karst settings, and some of the expected correlations between chemical parameters during the storms were not observed in this work. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Nevada, Nevada Bur Mines & Geol, Reno, NV 89557 USA. Oak Ridge Natl Lab, Environm Sci Div, Oak Ridge, TN 37831 USA. RP Shevenell, L (reprint author), Univ Nevada, Nevada Bur Mines & Geol, Mail Stop 178, Reno, NV 89557 USA. NR 37 TC 20 Z9 22 U1 3 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD JAN 2 PY 2002 VL 255 IS 1-4 BP 50 EP 68 DI 10.1016/S0022-1694(01)00510-8 PG 19 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 503LR UT WOS:000172800400005 ER PT J AU Bissell, MJ Le Beyec, J Anderson, RL AF Bissell, MJ Le Beyec, J Anderson, RL TI Prostate cancer in bone: Importance of context for inhibition of matrix metalloproteinases SO JOURNAL OF THE NATIONAL CANCER INSTITUTE LA English DT Editorial Material ID METASTASIS; BREAST; LEADS; CELLS C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. Peter MacCallum Canc Inst, Melbourne, Vic, Australia. RP Bissell, MJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, 1 Cyclotron Rd,MS 83-101, Berkeley, CA 94720 USA. RI Anderson, Robin/I-2306-2013 FU NCI NIH HHS [U54 CA112970-02, U54 CA143836-02, R01 CA057621-07, U54 CA126552-02, U01 CA143233, U01 CA143233-02, U54 CA112970, R01 CA064786-05, R01 CA057621, U54 CA143836, R01 CA064786, U54 CA126552] NR 23 TC 8 Z9 8 U1 0 U2 1 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 0027-8874 J9 J NATL CANCER I JI J. Natl. Cancer Inst. PD JAN 2 PY 2002 VL 94 IS 1 BP 4 EP 5 PG 2 WC Oncology SC Oncology GA 507YJ UT WOS:000173058600002 PM 11773268 ER PT B AU Fast, JD Darby, LS Banta, RM AF Fast, JD Darby, LS Banta, RM GP AMS AMS AMS TI The interaction of down-valley and canyon flows and their effect on mean vertical motions in the Salt Lake valley SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Fast, JD (reprint author), Pacific NW Natl Lab, POB 999,K9-30, Richland, WA 99352 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 2 EP 5 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700002 ER PT B AU Whiteman, CD Zhong, S Mayr, R AF Whiteman, CD Zhong, S Mayr, R GP AMS AMS AMS TI Katabatic flows on a low-angle slope in the Salt Lake valley overview of the VTMX 2000 slope experiment SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 PNNL, Richland, WA 99352 USA. RP Whiteman, CD (reprint author), PNNL, POB 999, Richland, WA 99352 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 6 EP 9 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700003 ER PT B AU Costigan, KR AF Costigan, KR GP AMS AMS AMS TI Circulations in the salt lake city basin: The influence of air exchanges with adjacent basins and canyons SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Los Alamos Natl Lab, Atmospher & Climate Sci Grp, Los Alamos, NM 87545 USA. RP Costigan, KR (reprint author), Los Alamos Natl Lab, Atmospher & Climate Sci Grp, POB 1663,EES-8 Mailstop D401, Los Alamos, NM 87545 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 10 EP 11 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700004 ER PT B AU Zhong, SY Fast, J AF Zhong, SY Fast, J GP AMS AMS AMS TI An evaluation of fine-scale MM5, RAMS, and Meso Eta simulations using VTMX field campaign data in the Salt Lake Valley SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Zhong, SY (reprint author), Pacific NW Natl Lab, POB 999,K9-30, Richland, WA 99352 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 16 EP 19 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700006 ER PT B AU Fast, JD Allwine, KJ Torcolini, JC Dietz, RN AF Fast, JD Allwine, KJ Torcolini, JC Dietz, RN GP AMS AMS AMS TI Perfluorocarbon tracer experiments during VTMX 2000 SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Fast, JD (reprint author), Pacific NW Natl Lab, POB 999,K9-30, Richland, WA 99352 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 42 EP 45 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700014 ER PT B AU Fast, JD Zhong, SY AF Fast, JD Zhong, SY GP AMS AMS AMS TI An evaluation of the sigma and step-mountain vertical coordinates in the Meso Eta model at sub-kilometer grid spacing SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Fast, JD (reprint author), Pacific NW Natl Lab, POB 999,K9-30, Richland, WA 99352 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 46 EP 49 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700015 ER PT B AU Stalker, JR AF Stalker, JR GP AMS AMS AMS TI Simulations of canyon drainage flow and its interaction with the stable air of the Salt Lake basin SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Stalker, JR (reprint author), Los Alamos Natl Lab, EES-8,Mailstop D401, Los Alamos, NM 87545 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 54 EP 56 PG 3 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700017 ER PT B AU Doran, JC AF Doran, JC GP AMS AMS AMS TI Variations in surface turbulence characteristics over the Salt-Lake valley during VTMX2002 SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Doran, JC (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 60 EP 61 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700019 ER PT B AU Zhong, SY Whiteman, CD Haiden, T AF Zhong, SY Whiteman, CD Haiden, T GP AMS AMS AMS TI How well can mesoscale models capture katabatic flows observed in a large valley SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Zhong, SY (reprint author), Pacific NW Natl Lab, POB 999,K9-30, Richland, WA 99352 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 69 EP 72 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700022 ER PT B AU Zhong, SY Bian, XD Whiteman, CD Tanrikulu, S AF Zhong, SY Bian, XD Whiteman, CD Tanrikulu, S GP AMS AMS AMS TI Thermally driven flows in California's Central valley: A comprehensive analysis using data from a dense wind profiler network SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Zhong, SY (reprint author), Pacific NW Natl Lab, POB 999,K9-30, Richland, WA 99352 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 73 EP 76 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700023 ER PT B AU Coulter, RL Pekour, MS Martin, TJ AF Coulter, RL Pekour, MS Martin, TJ GP AMS AMS AMS TI Evolution of elevated stratified layers during VTMX SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Argonne Natl Lab, Environm Res Div, Argonne, IL 60439 USA. RP Coulter, RL (reprint author), Argonne Natl Lab, Environm Res Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 77 EP 80 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700024 ER PT B AU Costigan, KR Wintercamp, JL Langley, DL Bossert, JE AF Costigan, KR Wintercamp, JL Langley, DL Bossert, JE GP AMS AMS AMS TI Multi-scale flow interactions in complex terrain SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program C1 Los Alamos Natl Lab, Atmospher & Climate Sci Grp, Los Alamos, NM 87545 USA. RP Costigan, KR (reprint author), Los Alamos Natl Lab, Atmospher & Climate Sci Grp, POB 1663,EES-8 Mailstop D401, Los Alamos, NM 87545 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 105 EP 108 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700032 ER PT B AU Shaw, WJ Hubbe, JM AF Shaw, WJ Hubbe, JM GP AMS AMS AMS TI Structure of the atmospheric boundary layer in the central Salt Lake Valley during the afternoon-to-evening transition SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program ID IMPROVED MOMENT ESTIMATION; CONVECTIVE TURBULENCE; DOPPLER SPECTRA; DECAY C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Shaw, WJ (reprint author), Pacific NW Natl Lab, POB 999,MS K9-30, Richland, WA 99352 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 112 EP 115 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700034 ER PT B AU Barnard, JC Shaw, WJ AF Barnard, JC Shaw, WJ GP AMS AMS AMS TI Direct numerical simulations of evolving turbulence using surface heat fluxes derived from VTMX measurements SO 10TH CONFERENCE ON MOUNTAIN METEOROLOGY LA English DT Proceedings Paper CT 10th Conference on Mountain Meteorology CY JUN 17-21, 2002 CL PARK CITY, UT SP Amer Meteorol Soc, Mesoscale Alpine Program ID CONVECTIVE TURBULENCE; BOUNDARY-LAYER; DECAY C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Barnard, JC (reprint author), Pacific NW Natl Lab, MSIN K9-30, Richland, WA 99352 USA. EM james.barnard@pnl.gov NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 122 EP 125 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX35S UT WOS:000185048700037 ER PT B AU Marchand, R Ackerman, T AF Marchand, R Ackerman, T GP AMS AMS TI Evaluation of radiometric measurements from the NASA multi-angle spectro-radiometer from an inhomogeneous cloud using a combination of 2D and 3D radiative transfer modeling and airborne measurements SO 11TH CONFERENCE ON ATMOSPHERIC RADIATION LA English DT Proceedings Paper CT 11th Conference on Atmospheric Radiation CY JUN 03-07, 2002 CL OGDEN, UT SP Amer Meteorol Soc C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Marchand, R (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 72 EP 75 PG 4 WC Instruments & Instrumentation; Meteorology & Atmospheric Sciences; Remote Sensing SC Instruments & Instrumentation; Meteorology & Atmospheric Sciences; Remote Sensing GA BX57X UT WOS:000185754900020 ER PT B AU Powell, DM Ackerman, TP Long, CN AF Powell, DM Ackerman, TP Long, CN GP AMS AMS TI Comparison of the modeled and measured diffuse irradiance for selected clear-sky cases at mid-latitude surfrad sites SO 11TH CONFERENCE ON ATMOSPHERIC RADIATION LA English DT Proceedings Paper CT 11th Conference on Atmospheric Radiation CY JUN 03-07, 2002 CL OGDEN, UT SP Amer Meteorol Soc ID SURFACE; ATMOSPHERE C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Powell, DM (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 8 TC 0 Z9 0 U1 1 U2 2 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 80 EP 81 PG 2 WC Instruments & Instrumentation; Meteorology & Atmospheric Sciences; Remote Sensing SC Instruments & Instrumentation; Meteorology & Atmospheric Sciences; Remote Sensing GA BX57X UT WOS:000185754900022 ER PT B AU Gardner, MK Feng, WC Fisk, M AF Gardner, MK Feng, WC Fisk, M GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Dynamic right-sizing in FTP (drsFTP): Enhancing grid performance in user-space SO 11TH IEEE INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 11th IEEE International Symposium on High Performance Distributed Computing (HPDC-11) CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP IEEE Tech Comm Distributed Processing AB With the advent of computational grids, networking performance over the wide-area network (WAN) has become a critical component in the grid infrastructure. Unfortunately, many, high-performance grid applications only use a small raction of the available bandwidth because operating systems and their associated protocol stacks are still tuned for yesterday's WAN speeds. As a result, network gurus undertake the tedious process of manually tuning system buffers to allow TCP flow control to scale to today's WAN grid environments. Although recent research has shown how to set the size of these system buffers automatically at connection set-up, the buffer sizes are only appropriate at the beginning of the connection's lifetime. To address these problems, we describe an automated and scalable technique called dynamic right-sizing. We implement this technique in user space (in particular for bulk-data transfer) so that end users do not have to modify the kernel to achieve a significant increase in throughput. C1 Los Alamos Natl Lab, Comp & Comp Sci Div, Res & Dev Adv Network Technol, Los Alamos, NM 87545 USA. RP Gardner, MK (reprint author), Los Alamos Natl Lab, Comp & Comp Sci Div, Res & Dev Adv Network Technol, POB 1663, Los Alamos, NM 87545 USA. NR 28 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 0-7695-1686-6 PY 2002 BP 42 EP 49 DI 10.1109/HPDC.2002.1029902 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BU96F UT WOS:000177508900005 ER PT B AU Gunter, D Tierney, B Jackson, K Lee, J Stoufer, M AF Gunter, D Tierney, B Jackson, K Lee, J Stoufer, M GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Dynamic monitoring of high-performance distributed applications SO 11TH IEEE INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 11th IEEE International Symposium on High Performance Distributed Computing (HPDC-11) CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP IEEE Tech Comm Distributed Processing AB Developers and users of high-performance distributed systems often observe performance problems such as unexpectedly low throughput or high latency. Determining the source of the performance problems requires detailed end-to-end instrumentation of all components, including the applications, operating systems, hosts, and networks. However, ones must be very careful to design the instrumentation to have extremely low overhead, and not affect the system being monitored. In this paper we present a very light-weight instrumentation system that can be dynamically activated to unobtrusively collect and aggregate detailed end-to-end monitoring information from distributed applications. We also show how emerging "Web Services" can be used to facilitate remote interaction with this system. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Comp Sci Directorate, Berkeley, CA 94720 USA. RP Gunter, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Comp Sci Directorate, Berkeley, CA 94720 USA. NR 26 TC 12 Z9 12 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 0-7695-1686-6 PY 2002 BP 163 EP 170 DI 10.1109/HPDC.2002.1029915 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BU96F UT WOS:000177508900017 ER PT B AU Allcock, W Bester, J Bresnahan, J Foster, I Gawor, J Insley, JA Link, JM Papka, ME AF Allcock, W Bester, J Bresnahan, J Foster, I Gawor, J Insley, JA Link, JM Papka, ME GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI GridMapper: A tool for visualizing the behavior of large-scale distributed systems SO 11TH IEEE INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 11th IEEE International Symposium on High Performance Distributed Computing (HPDC-11) CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP IEEE Tech Comm Distributed Processing ID NETWORK AB Grid applications can combine the use of compute, storage, network, and other resources. These resources are often geographically, distributed, adding to application complexity and thus the difficulty, of understanding application performance. We present GridMapper, a tool for monitoring and visualizing the behavior of such distributed systems. GridMapper builds on basic mechanisms for registering, discovering, and accessing performance information sources, as well as for mapping from domain names to physical locations. The visualization system itself then supports the automatic layout of distributed sets of such sources and animation of their activities. We use a set of examples to illustrate how the system can provide valuable insights into the behavior and performance of a range of different applications. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Allcock, W (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 18 TC 4 Z9 4 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 0-7695-1686-6 PY 2002 BP 179 EP 187 DI 10.1109/HPDC.2002.1029917 PG 9 WC Computer Science, Theory & Methods SC Computer Science GA BU96F UT WOS:000177508900019 ER PT B AU Vazhkudai, S Schopf, JM AF Vazhkudai, S Schopf, JM GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Predicting sporadic grid data transfers SO 11TH IEEE INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 11th IEEE International Symposium on High Performance Distributed Computing (HPDC-11) CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP IEEE Tech Comm Distributed Processing DE Grids; data transfer prediction; replica selection AB The increasingly common practice of replicating datasets and using resources as distributed data stores in Grid environments has led to the problem of determining which replica can be accessed most efficiently. Because of diverse performance characteristics and load variations of several components in the end-to-end path linking these various locations, selecting a replica from among many requires accurate prediction information of the data transfer times between the sources and sinks. In this paper we present a prediction system that is based on combining end-to-end application throughput observations and network load variations, capturing whole, system performance and variations in load patterns, respectively. We develop a set of regression models to derive predictions that characterize the effect of network load variations on file transfer times. We apply these techniques to the GridFTP data movement tool, part of the Globus Toolkit(TM), and observe performance gains of up to 10% in prediction accuracy when compared with approaches based on past system behavior in isolation. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. EM vazhkuda@mcs.anl.gov; jms@mcs.anl.gov NR 33 TC 22 Z9 22 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 0-7695-1686-6 PY 2002 BP 188 EP 196 DI 10.1109/HPDC.2002.1029918 PG 9 WC Computer Science, Theory & Methods SC Computer Science GA BU96F UT WOS:000177508900020 ER PT B AU Johnson, WR AF Johnson, WR GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Design and implementation of secured information services for the ASCI Grid SO 11TH IEEE INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 11th IEEE International Symposium on High Performance Distributed Computing (HPDC-11) CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP IEEE Tech Comm Distributed Processing AB Information services are an integral part of the grid architecture. It is the foundation of how resources are defined and their state known. More importantly, the user of the Grid gets a perspective of what a grid looks like, how it performs and what capabilities it has from information services. The Accelerated Strategic Computing Initiative(1) (ASCI) has designed and deployed a set of grid services within the context of the ASCI program. We deploy information services by augmenting the Globus toolkit in order to meet the unique aspects of the ASCI grid. In this paper we describe the decisions made and processes developed to run a grid information service in the ASCI grid. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800,MS 1137, Albuquerque, NM 87185 USA. EM wrjohns@sandia.gov NR 4 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 0-7695-1686-6 PY 2002 BP 209 EP 214 DI 10.1109/HPDC.2002.1029920 PG 6 WC Computer Science, Theory & Methods SC Computer Science GA BU96F UT WOS:000177508900022 ER PT B AU Weigle, E Feng, WC AF Weigle, E Feng, WC GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI A comparison of TCP automatic tuning techniques for distributed computing SO 11TH IEEE INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 11th IEEE International Symposium on High Performance Distributed Computing (HPDC-11) CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP IEEE Tech Comm Distributed Processing DE dynamic right-sizing; autotuning; high-performance networking; TCP; flow control; wide-area network AB Rather than painful, manual, static, per-connection optimization of TCP buffer sizes simply to achieve acceptable performance for distributed applications [8, 10], many researchers have proposed techniques to perform this tuning automatically [4, 7, 9, 11, 12, 14]. This paper first discusses the relative merits of the various approaches in theory, and then provides substantial experimental data concerning two competing implementations - the buffer autotuning already present in Linux 2.4.x and "Dynamic Right-Sizing." This paper reveals heretofore unknown aspects of the problem and current solutions, provides insight into the proper approach for different circumstances, and points toward ways to further improve performance. C1 Los Alamos Natl Lab, Comp & Computat Sci Div, Los Alamos, NM 87545 USA. RP Weigle, E (reprint author), Los Alamos Natl Lab, Comp & Computat Sci Div, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 4 Z9 4 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 0-7695-1686-6 PY 2002 BP 265 EP 272 DI 10.1109/HPDC.2002.1029926 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BU96F UT WOS:000177508900028 ER PT B AU von Laszewski, G Gawor, J Pena, CJ Foster, I AF von Laszewski, G Gawor, J Pena, CJ Foster, I GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI InfoGram: A grid service that supports both information queries and job execution SO 11TH IEEE INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 11th IEEE International Symposium on High Performance Distributed Computing (HPDC-11) CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP IEEE Tech Comm Distributed Processing AB The research described in this paper is performed as part of the Globus Project. It introduces a new Grid service called InfoGram that combines the ability of serving as information service and as a job execution service. Previously, both services were architected and implemented within the Globus Toolkit as two different services with different wire protocols. Our service demonstrates a significant simplification of the architecture while treating job submissions and information queries alike. The advantage of our service is that it provides backwards compatibility to existing Grid services, while at the same time providing forwards compatibility to the emerging Web services world. Part of the work conducted within this effort is already reused by the current Open Grid Services Architecture prototype implementation. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP von Laszewski, G (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 30 TC 6 Z9 6 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 0-7695-1686-6 PY 2002 BP 333 EP 342 DI 10.1109/HPDC.2002.1029933 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA BU96F UT WOS:000177508900035 ER PT B AU Corey, IR Johnson, JR Vetter, JS AF Corey, IR Johnson, JR Vetter, JS GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Local discovery of system architecture - Application parameter sensitivity: An empirical technique for adaptive grid applications SO 11TH IEEE INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE DISTRIBUTED COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT 11th IEEE International Symposium on High Performance Distributed Computing (HPDC-11) CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP IEEE Tech Comm Distributed Processing AB This study presents a technique that can significantly improve the performance of a distributed application by allowing the application to locally adapt to architectural characteristics of distinct resources in a distributed system. Application performance is sensitive to system architecture-application parameter pairings. In a distributed or Grid enabled application, a single parameter configuration for the whole application will not always be optimal for every participating resource. In particular, some configurations can significantly degrade performance. Furthermore, the behavior of a system may change during the course of the run. The technique described here provides an automated mechanism for run-time adaptation of application parameters to the local system architecture. Using a scaled-down simulation of a Monte Carlo physics code, we demonstrate that this technique can conservatively achieve speedups up to 65% on individual resources and may even provide order of magnitude speedup in the extreme case. C1 Lawrence Livermore Natl Lab, Comp Applicat & Res Dept, Livermore, CA USA. RP Corey, IR (reprint author), Lawrence Livermore Natl Lab, Comp Applicat & Res Dept, Livermore, CA USA. NR 14 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 0-7695-1686-6 PY 2002 BP 399 EP 407 DI 10.1109/HPDC.2002.1029940 PG 9 WC Computer Science, Theory & Methods SC Computer Science GA BU96F UT WOS:000177508900042 ER PT B AU Leung, LR Bian, XD Qian, Y AF Leung, LR Bian, XD Qian, Y GP AMS AMS TI Long-term regional climate simulations driven by two global reanalyses and a GCM for the western US SO 13TH SYMPOSIUM ON GLOBAL CHANGE AND CLIMATE VARIATIONS LA English DT Proceedings Paper CT 13th Symposium on Global Change and Climate Variations CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc C1 Battelle Mem Inst, Pacific NW Natl Labs, Global Environm Change, Richland, WA 99352 USA. RP Leung, LR (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, Global Environm Change, Richland, WA 99352 USA. RI qian, yun/A-5056-2010 NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 65 EP 67 PG 3 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BV58M UT WOS:000179447900025 ER PT B AU Gleckler, P Taylor, K AF Gleckler, P Taylor, K GP AMS AMS TI Implied ocean heat transports in recent AGCM simulations: Sensitivity to the surface energy budget SO 13TH SYMPOSIUM ON GLOBAL CHANGE AND CLIMATE VARIATIONS LA English DT Proceedings Paper CT 13th Symposium on Global Change and Climate Variations CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc C1 Lawrence Livermore Natl Lab, Program Climate Model Diagnost & Intercomparison, Livermore, CA 94550 USA. RP Gleckler, P (reprint author), Lawrence Livermore Natl Lab, Program Climate Model Diagnost & Intercomparison, Mail Code L-264,7000 E Ave, Livermore, CA 94550 USA. NR 2 TC 0 Z9 0 U1 1 U2 2 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 68 EP 69 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BV58M UT WOS:000179447900026 ER PT B AU Scott, D Blasing, TJ Kaiser, D AF Scott, D Blasing, TJ Kaiser, D GP AMS AMS TI Evidence for a recent advance in the timing of a surface-air warming SO 13TH SYMPOSIUM ON GLOBAL CHANGE AND CLIMATE VARIATIONS LA English DT Proceedings Paper CT 13th Symposium on Global Change and Climate Variations CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc ID UNITED-STATES; HEIGHT FIELD; TEMPERATURE C1 Oak Ridge Natl Lab, Carbon Dioxide Informat Anal Ctr, Oak Ridge, TN 37831 USA. RP Blasing, TJ (reprint author), Oak Ridge Natl Lab, Carbon Dioxide Informat Anal Ctr, Mail Stop 6335,Bldg 1509, Oak Ridge, TN 37831 USA. RI Blasing, T/B-9498-2012 NR 16 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 73 EP 76 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BV58M UT WOS:000179447900028 ER PT B AU Gleckler, P Taylor, K AF Gleckler, P Taylor, K GP AMS AMS TI The atmospheric model intercomparison project (AMIP): Progress and plans SO 13TH SYMPOSIUM ON GLOBAL CHANGE AND CLIMATE VARIATIONS LA English DT Proceedings Paper CT 13th Symposium on Global Change and Climate Variations CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc C1 Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercompar, Livermore, CA 94550 USA. RP Gleckler, P (reprint author), Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercompar, Mail Code L-264,7000 East Ave, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 214 EP 215 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BV58M UT WOS:000179447900080 ER PT B AU Covey, C AchutaRao, KM Gleckler, PJ Taylor, KE Wehner, MF AF Covey, C AchutaRao, KM Gleckler, PJ Taylor, KE Wehner, MF GP AMS AMS TI Coupled ocean-atmosphere vs. prescribed-SST simulations: Effect of a "perfect ocean" SO 13TH SYMPOSIUM ON GLOBAL CHANGE AND CLIMATE VARIATIONS LA English DT Proceedings Paper CT 13th Symposium on Global Change and Climate Variations CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc C1 Lawrence Livermore Natl Lab, Program Climate Model Diagnost & Intercompar, Livermore, CA 94550 USA. RP Covey, C (reprint author), Lawrence Livermore Natl Lab, Program Climate Model Diagnost & Intercompar, Mail Code L-264,700 East Ave, Livermore, CA 94550 USA. NR 3 TC 0 Z9 0 U1 0 U2 2 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 216 EP 217 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BV58M UT WOS:000179447900081 ER PT B AU Weber, AH Buckley, RL Parker, MJ Brown, ME AF Weber, AH Buckley, RL Parker, MJ Brown, ME GP AMS AMS TI Wind speed and direction analyses for a group of southeast surface stations SO 13TH SYMPOSIUM ON GLOBAL CHANGE AND CLIMATE VARIATIONS LA English DT Proceedings Paper CT 13th Symposium on Global Change and Climate Variations CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc C1 Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Weber, AH (reprint author), Savannah River Technol Ctr, Bldg 773A, Aiken, SC 29808 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 245 EP 247 PG 3 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BV58M UT WOS:000179447900093 ER PT B AU Foster, I Vockler, J Wilde, M Zhao, Y AF Foster, I Vockler, J Wilde, M Zhao, Y BE Kennedy, J TI Chimera: A virtual data system for representing, querying, and automating data derivation SO 14TH INTERNATIONAL CONFERENCE ON SCIENTIFIC AND STATISTICAL DATABASE MANAGEMENT, PROCEEDINGS LA English DT Proceedings Paper CT 14th International Conference on Scientific and Statistical Database Management CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP Napier Univ, Edinburgh Univ, Heriot Watt Univ, VLDB Endowment, Int Assoc Stat Comp ID ARCHITECTURE AB Much scientific data is not obtained from measurements but rather derived from other data by the application of computational procedures. We hypothesize that explicit representation of these procedures can enable documentation of data provenance, discovery of available methods, and on-demand data generation (so-called "virtual data"). To explore this idea, we have developed the Chimera virtual data system, which combines a virtual data catalog, for representing data derivation procedures and derived data, with a virtual data language interpreter that translates user requests into data definition and query operations on the database. We couple the Chimera system with distributed "Data Grid" services to enable on-demand execution of computation schedules constructed from database queries. We have applied this system to two challenge problems, the reconstruction of simulated collision event data from a high-energy physics experiment, and the search of digital sky survey data for galactic clusters, with promising results. C1 Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. RP Foster, I (reprint author), Argonne Natl Lab, Math & Comp Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 32 TC 80 Z9 84 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 0-7695-1632-7 PY 2002 BP 37 EP 46 DI 10.1109/SSDM.2002.1029704 PG 10 WC Computer Science, Information Systems; Statistics & Probability SC Computer Science; Mathematics GA BV05L UT WOS:000177691100007 ER PT B AU Wu, KS Otoo, EJ Shoshani, A AF Wu, KS Otoo, EJ Shoshani, A BE Kennedy, J TI Compressing bitmap indexes for faster search operations SO 14TH INTERNATIONAL CONFERENCE ON SCIENTIFIC AND STATISTICAL DATABASE MANAGEMENT, PROCEEDINGS LA English DT Proceedings Paper CT 14th International Conference on Scientific and Statistical Database Management CY JUL 24-26, 2002 CL EDINBURGH, SCOTLAND SP Napier Univ, Edinburgh Univ, Heriot Watt Univ, VLDB Endowment, Int Assoc Stat Comp AB In this paper we study the effects of compression on bitmap indexes. The main operations on the bitmaps during query, processing are bitwise logical operations such as AND, OR, NOT etc. Using, the general purpose compression schemes, such as gzip, the logical operations on the compressed bitmaps are much slower than on the uncompressed bitmaps. Specialized compression schemes, like the byte-aligned bitmap code (BBC), are usually faster in performing logical operations than the general purpose schemes, but in many cases they are still orders of magnitude slower than the uncompressed scheme. To make the compressed bitmap indexes operate more efficiently, we designed a CPU-friendly scheme which we refer to as the word-aligned hybrid code (WAH). Tests on both synthetic and real application data show that the new scheme significantly outperforms well-known compression schemes at a modest increase in storage space. Compared to BBC, a scheme well-known for its operational efficiency, WAH performs logical operations about 12 times faster and uses only 60% more space. Compared to the uncompressed scheme, in most test cases WAH is faster while still using less space. We further verified with additional tests that the improvement in logical operation speed translates to similar improvement in query processing speed. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Wu, KS (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 28 TC 2 Z9 2 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 0-7695-1632-7 PY 2002 BP 99 EP 108 DI 10.1109/SSDM.2002.1029710 PG 10 WC Computer Science, Information Systems; Statistics & Probability SC Computer Science; Mathematics GA BV05L UT WOS:000177691100013 ER PT B AU Stevens, D AF Stevens, D GP AMS AMS TI Effects of domain size and numerical resolution on the simulation of shallow cumulus convection SO 15TH SYMPOSIUM ON BOUNDARY LAYERS AND TURBULENCE LA English DT Proceedings Paper CT 15th Symposium on Boundary Layers and Turbulence CY JUL 15-19, 2002 CL WAGENINGEN, NETHERLANDS SP Amer Meteorol Soc, Wageningen Univ, Dept Meteorol & Air Qual C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Stevens, D (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, 7000 East Ave, Livermore, CA 94550 USA. NR 6 TC 0 Z9 0 U1 0 U2 2 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 108 EP 111 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX63B UT WOS:000185937700031 ER PT B AU Zhong, S Jiang, GF Yang, E Tanrikulu, S AF Zhong, S Jiang, GF Yang, E Tanrikulu, S GP AMS AMS TI The impact of forecast errors in boundary layer wind and temperature fields on predictions of surface ozone concentrations SO 15TH SYMPOSIUM ON BOUNDARY LAYERS AND TURBULENCE LA English DT Proceedings Paper CT 15th Symposium on Boundary Layers and Turbulence CY JUL 15-19, 2002 CL WAGENINGEN, NETHERLANDS SP Amer Meteorol Soc, Wageningen Univ, Dept Meteorol & Air Qual C1 Pacific NW Natl Lab, Richland, WA USA. RP Zhong, S (reprint author), POB 999,K9-30, Richland, WA 99352 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 362 EP 363 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX63B UT WOS:000185937700106 ER PT B AU Shaw, WJ Barnard, JC AF Shaw, WJ Barnard, JC GP AMS AMS TI Scales of turbulence decay from observations and direct numerical simulation SO 15TH SYMPOSIUM ON BOUNDARY LAYERS AND TURBULENCE LA English DT Proceedings Paper CT 15th Symposium on Boundary Layers and Turbulence CY JUL 15-19, 2002 CL WAGENINGEN, NETHERLANDS SP Amer Meteorol Soc, Wageningen Univ, Dept Meteorol & Air Qual ID IMPROVED MOMENT ESTIMATION; CONVECTIVE TURBULENCE; DOPPLER SPECTRA C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, POB 999,MS K9-30, Richland, WA 99352 USA. EM will.shaw@pnl.gov NR 9 TC 0 Z9 0 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 398 EP 401 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX63B UT WOS:000185937700116 ER PT B AU Barnard, JC Riley, JJ AF Barnard, JC Riley, JJ GP AMS AMS TI Direct numerical simulations of intermittent turbulence in the very stable Ekman layer SO 15TH SYMPOSIUM ON BOUNDARY LAYERS AND TURBULENCE LA English DT Proceedings Paper CT 15th Symposium on Boundary Layers and Turbulence CY JUL 15-19, 2002 CL WAGENINGEN, NETHERLANDS SP Amer Meteorol Soc, Wageningen Univ, Dept Meteorol & Air Qual ID ATMOSPHERIC BOUNDARY-LAYERS; INSTABILITY; BREAKDOWN; WAVES C1 Pacific NW Natl Lab, MSIN, Richland, WA 99352 USA. RP Pacific NW Natl Lab, MSIN, K9-30, Richland, WA 99352 USA. EM james.barnard@pnl.gov NR 17 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 424 EP 427 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX63B UT WOS:000185937700123 ER PT B AU Cederwall, RT Street, RL AF Cederwall, RT Street, RL GP AMS AMS TI Investigation of episodic enhancement of turbulence in the stable boundary layer using large-eddy simulation SO 15TH SYMPOSIUM ON BOUNDARY LAYERS AND TURBULENCE LA English DT Proceedings Paper CT 15th Symposium on Boundary Layers and Turbulence CY JUL 15-19, 2002 CL WAGENINGEN, NETHERLANDS SP Amer Meteorol Soc, Wageningen Univ, Dept Meteorol & Air Qual C1 Lawrence Livermore Natl Lab, Atmospher Sci Div L103, Livermore, CA 94551 USA. RP Cederwall, RT (reprint author), Lawrence Livermore Natl Lab, Atmospher Sci Div L103, POB 808, Livermore, CA 94551 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 469 EP 472 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX63B UT WOS:000185937700135 ER PT B AU Zhong, SY Fast, J AF Zhong, SY Fast, J GP AMS AMS TI An evaluation of boundary layer and land surface parameterizations using data from the VTMX Field Campaign in the Salt Lake Valley SO 15TH SYMPOSIUM ON BOUNDARY LAYERS AND TURBULENCE LA English DT Proceedings Paper CT 15th Symposium on Boundary Layers and Turbulence CY JUL 15-19, 2002 CL WAGENINGEN, NETHERLANDS SP Amer Meteorol Soc, Wageningen Univ, Dept Meteorol & Air Qual C1 Pacific NW Natl Lab, Richland, WA USA. RP Zhong, SY (reprint author), POB 999,K9-30, Richland, WA 99352 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 560 EP 563 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX63B UT WOS:000185937700159 ER PT B AU Fast, JD Shaw, WJ AF Fast, JD Shaw, WJ GP AMS AMS TI Observed and simulated turbulence kinetic energy and dissipation profiles in an urban valley during VTMX 2000 SO 15TH SYMPOSIUM ON BOUNDARY LAYERS AND TURBULENCE LA English DT Proceedings Paper CT 15th Symposium on Boundary Layers and Turbulence CY JUL 15-19, 2002 CL WAGENINGEN, NETHERLANDS SP Amer Meteorol Soc, Wageningen Univ, Dept Meteorol & Air Qual ID IMPROVED MOMENT ESTIMATION; DOPPLER SPECTRA C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Fast, JD (reprint author), Pacific NW Natl Lab, POB 999,k9-30, Richland, WA 99352 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 638 EP 641 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX63B UT WOS:000185937700183 ER PT B AU Whiteman, CD Clements, CB Horel, JD AF Whiteman, CD Clements, CB Horel, JD GP AMS AMS TI Turbulent and radiative flux divergences in cold pools that form within a high-elevation basin SO 15TH SYMPOSIUM ON BOUNDARY LAYERS AND TURBULENCE LA English DT Proceedings Paper CT 15th Symposium on Boundary Layers and Turbulence CY JUL 15-19, 2002 CL WAGENINGEN, NETHERLANDS SP Amer Meteorol Soc, Wageningen Univ, Dept Meteorol & Air Qual C1 PNNL, Richland, WA 99352 USA. RP Whiteman, CD (reprint author), PNNL, POB 999, Richland, WA 99352 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 662 EP 665 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BX63B UT WOS:000185937700191 ER PT B AU Choi, SE Hendriks, EA Minnich, RG Sottile, MJ Marks, AJ AF Choi, SE Hendriks, EA Minnich, RG Sottile, MJ Marks, AJ GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Life with Ed: A case study of a LinuxBIOS/BProc cluster SO 16TH ANNUAL INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE COMPUTING SYSTEMS AND APPLICATIONS, PROCEEDINGS LA English DT Proceedings Paper CT 16th Annual International Symposium on High Performance Computing Systems and Applications CY JUN 16-19, 2002 CL MONCTON, CANADA SP Atlantic Canada Opportunities Agcy, Business New Brunswick, C3 ca Assoc Inc, City Moncton, COMPAQ Canada, IBM Canada, IEEE Comp Soc Tech Comm Comp Architecture, IEEE New Brunswick, Natl Res Council, Univ Moncton, Univ New Brunswick AB In this paper, we describe experiences with our 127-mode/161-processor Alpha cluster testbed, Ed. Ed is unique for two distinct reasons. First, we have replaced the standard BIOS on the cluster nodes with the LinuxBIOS which loads Linux directly from non-volatile memory (Flash RAM). Second, the operating system provides a single-system image of the entire cluster, much like a traditional supercomputer. We will discuss the advantages of such a cluster, including time to boot (101 seconds for 100 nodes), upgrade (same as time to boot), and start processes (2.4 seconds for 15,000 processes). Additionally, we have discovered that certain predictions about the nature of terascale clusters, such as the need for hierarchical structure, are false. Finally, we argue that to achieve true scalability, terascale clusters must be built in the way of Ed. C1 Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. RP Choi, SE (reprint author), Los Alamos Natl Lab, Adv Comp Lab, POB 1663, Los Alamos, NM 87545 USA. NR 14 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 0-7695-1626-2 PY 2002 BP 35 EP 41 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BU84H UT WOS:000177164000005 ER PT B AU Choi, SE Deitz, SJ AF Choi, SE Deitz, SJ GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Compiler support for automatic checkpointing SO 16TH ANNUAL INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE COMPUTING SYSTEMS AND APPLICATIONS, PROCEEDINGS LA English DT Proceedings Paper CT 16th Annual International Symposium on High Performance Computing Systems and Applications CY JUN 16-19, 2002 CL MONCTON, CANADA SP Atlantic Canada Opportunities Agcy, Business New Brunswick, C3 ca Assoc Inc, City Moncton, COMPAQ Canada, IBM Canada, IEEE Comp Soc Tech Comm Comp Architecture, IEEE New Brunswick, Natl Res Council, Univ Moncton, Univ New Brunswick AB Checkpointing is a key technology for applications on large cluster computer systems. As cluster sizes grow, component failures will become a normal part of operation, and applications will have to deal more directly with repeated failures during program runs. In this paper, we describe automatic checkpointing in the ZPL compiler and its advantages over traditional library- or system-based approaches that have no information about application behavior. We show that even naive compiler-inserted checkpoints can significantly reduce the size of the checkpoint recovery data, up to 73% in our application suite. We also introduce the notion of checkpoint ranges, a range of code where processors can perform a local checkpoint at any time during the range. The compiler guarantees that these local checkpoints form a globally consistent checkpoint without global coordination by ensuring that there are no in-flight messages during the checkpoint range. Checkpoint ranges help further alleviate any additional network congestion caused by checkpointing. C1 Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. RP Choi, SE (reprint author), Los Alamos Natl Lab, Adv Comp Lab, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 1 Z9 1 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 0-7695-1626-2 PY 2002 BP 213 EP 220 DI 10.1109/HPCSA.2002.1019157 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BU84H UT WOS:000177164000031 ER PT B AU Buckley, RL Weber, AH Weber, JH AF Buckley, RL Weber, AH Weber, JH GP AMS AMS TI Statistical comparison of forecast meteorology with observations using the regional atmospheric modeling system SO 16TH CONFERENCE ON PROBABILITY AND STATISTICS IN THE ATMOSPHERIC SCIENCES LA English DT Proceedings Paper CT 16th Conference on Probability and Statistics in the Atmospheric Sciences CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc ID MESOSCALE MODEL; RAMS C1 Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Buckley, RL (reprint author), Savannah River Technol Ctr, Bldg 773A, Aiken, SC 29808 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 55 EP 60 PG 6 WC Meteorology & Atmospheric Sciences; Statistics & Probability SC Meteorology & Atmospheric Sciences; Mathematics GA BV55E UT WOS:000179335800010 ER PT B AU Weber, AH Parker, MJ Weber, JH AF Weber, AH Parker, MJ Weber, JH GP AMS AMS TI Surface wind gust statistics at the Savannah River Site SO 16TH CONFERENCE ON PROBABILITY AND STATISTICS IN THE ATMOSPHERIC SCIENCES LA English DT Proceedings Paper CT 16th Conference on Probability and Statistics in the Atmospheric Sciences CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc C1 Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Weber, AH (reprint author), Savannah River Technol Ctr, Bldg 773A, Aiken, SC 29808 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 120 EP 125 PG 6 WC Meteorology & Atmospheric Sciences; Statistics & Probability SC Meteorology & Atmospheric Sciences; Mathematics GA BV55E UT WOS:000179335800023 ER PT S AU Yang, Q Parvin, B AF Yang, Q Parvin, B BE Kasturi, R Laurendeau, D Suen, C TI Harmonic cut and regularized centroid transform for localization of subcellular structures SO 16TH INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION, VOL I, PROCEEDINGS SE INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION LA English DT Proceedings Paper CT 16th International Conference on Pattern Recognition (ICPR) CY AUG 11-15, 2002 CL QUEBEC CITY, CANADA SP Int Assoc Pattern Recognit, Canadian Image Processing & Pattern Recognit Soc, Ctr Rech Informat Montreal, Matrox Imaging, Ind & Commerce Quebec, Rech, Sci & Technol Quebec, Microsoft Res, Bell, Lab Vis & Syst Numer, Comp Vis & Syst Lab, Ctr Pattern Recognit & Machine Intelligence, Ctr Etudes Reconnaissance Formes & Intelligence Artificielle, Scribers, Coreco Imaging, Precarn DE segmentation; scale-space; regularization; vector field ID CELL IMAGE SEGMENTATION AB Two novel computational techniques, harmonic cut and regularized centroid transform, are developed for segmentation of cells and their corresponding substructures observed with an epi-fluorescence microscope. Harmonic cut detects small regions that correspond to subcellular structures. These regions also affect the accuracy of the overall segmentation. They are detected, removed, and interpolated to ensure continuity within each region. We show that interpolation within each region (subcellular compartment) is equivalent to solving the Laplace equation on a multi-connected domain with irregular boundaries. The second technique, referred to as the regularized centroid transform, aims to separate touching compartments. This is achieved by, adopting a quadratic model for the shape of the object and relaxing it for final segmentation. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Yang, Q (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 8 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 SN 1051-4651 BN 0-7695-1695-X J9 INT C PATT RECOG PY 2002 BP 788 EP 791 PG 4 WC Computer Science, Artificial Intelligence; Engineering, Biomedical; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology SC Computer Science; Engineering; Imaging Science & Photographic Technology GA BV11L UT WOS:000177847900190 ER PT S AU Yang, Q Parvin, B AF Yang, Q Parvin, B BE Kasturi, R Laurendeau, D Suen, C TI High-resolution reconstruction of sparse data from dense low-resolution spatio-temporal data SO 16TH INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION, VOL II, PROCEEDINGS SE INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION LA English DT Proceedings Paper CT 16th International Conference on Pattern Recognition (ICPR) CY AUG 11-15, 2002 CL QUEBEC CITY, CANADA SP Int Assoc Pattern Recognit, Canadian Image Processing & Pattern Recognit Soc, Ctr Rech Informat Montreal, Matrox Imaging, Ind & Commerce Quebec, Rech, Sci & Technol Quebec, Microsoft Res, Bell, Lab Vis & Syst Numer, Comp Vis & Syst Lab, Ctr Pattern Recognit & Machine Intelligence, Ctr Etudes Reconnaissance Formes & Intelligence Artificielle, Scribers, Coreco Imaging, Precarn ID OPTICAL-FLOW AB A novel approach for reconstruction of sparse high-resolution data from lower-resolution dense spatio-temporal data is introduced. The basic idea is to compute the dense feature velocities from lower-resolution data and project them to the corresponding high-resolution data for computing the missing data. In this context, the basic flow equation is solved for intensity, as opposed to feature velocities at high resolution. Although the proposed technique is generic, we have applied our approach to sea surface temperature (SST) data at 18 km (low-resolution dense data) for computing the feature velocities and at 4 km (high-resolution sparse data) for interpolating the missing data. At low resolution, computation of flow field is regularized and uses the incompressibility constraints for tracking fluid motion. At high resolution, computation of intensity is regularized for continuity across multiple frames. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Yang, Q (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 5 TC 0 Z9 0 U1 5 U2 5 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1051-4651 BN 0-7695-1695-X J9 INT C PATT RECOG PY 2002 BP 261 EP 264 PG 4 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology SC Computer Science; Engineering; Imaging Science & Photographic Technology GA BV12P UT WOS:000177886900065 ER PT S AU Yang, Q Parvin, B AF Yang, Q Parvin, B BE Kasturi, R Laurendeau, D Suen, C TI CHEF: Convex hull of elliptic features for 3D blob detection SO 16TH INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION, VOL II, PROCEEDINGS SE INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION LA English DT Proceedings Paper CT 16th International Conference on Pattern Recognition (ICPR) CY AUG 11-15, 2002 CL QUEBEC CITY, CANADA SP Int Assoc Pattern Recognit, Canadian Image Processing & Pattern Recognit Soc, Ctr Rech Informat Montreal, Matrox Imaging, Ind & Commerce Quebec, Rech, Sci & Technol Quebec, Microsoft Res, Bell, Lab Vis & Syst Numer, Comp Vis & Syst Lab, Ctr Pattern Recognit & Machine Intelligence, Ctr Etudes Reconnaissance Formes & Intelligence Artificielle, Scribers, Coreco Imaging, Precarn DE convex hull; blob detection; cell segmentation ID SEGMENTATION; ALGORITHM; IMAGES AB We present an efficient protocol for robust detection of 3D blobs from volumetric datasets. The approach has three steps. The first step of the process detects elliptic features by classifying the Hessian of the scale space representation of the volume data. These features are then grouped into 3D connected components, which are subsequently partitioned by computing a convex hull of each connected component. The proposed framework has been applied to a database of multicellular systems for detailed quantitative analysis. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Yang, Q (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 12 TC 4 Z9 4 U1 1 U2 2 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1051-4651 BN 0-7695-1695-X J9 INT C PATT RECOG PY 2002 BP 282 EP 285 PG 4 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology SC Computer Science; Engineering; Imaging Science & Photographic Technology GA BV12P UT WOS:000177886900071 ER PT B AU Klaus, CM McCollum, T Vernon, E Andrew, K Mace, GG Bahrmann, CP AF Klaus, CM McCollum, T Vernon, E Andrew, K Mace, GG Bahrmann, CP GP AMS AMS TI Educational and research applications of the NSDL/AVC SO 18TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY, AND HYDROLOGY LA English DT Proceedings Paper CT 18th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography and Hydrology CY JAN 13-17, 2002 CL ORLANDO, FL SP Amer Meteorol Soc C1 ANL, Austin, TX 78758 USA. RP Klaus, CM (reprint author), ANL, 11915 Stonehollow Dr,837B, Austin, TX 78758 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2002 BP 169 EP 170 PG 2 WC Computer Science, Information Systems; Computer Science, Software Engineering; Meteorology & Atmospheric Sciences SC Computer Science; Meteorology & Atmospheric Sciences GA BV55B UT WOS:000179335200064 ER PT B AU Loesser, GD Rushinski, J Bernabei, S Hosea, JC Wilson, JR AF Loesser, GD Rushinski, J Bernabei, S Hosea, JC Wilson, JR GP IEEE IEEE TI Design and engineering of the alcator C-Mod lower hybrid current drive system SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The PSFC group of MIT and PPPL are jointly developing a Lower Hybrid Current Drive (LHCD) system for installation on the Alcator C-Mod tokamak, with the primary goal of driving plasma current. Twelve Klystrons will feed a coupler with an input power of 3 MW at 4.6 GHz and a pulse length of 5 seconds. The coupler is composed of 4 arrays, each with 24 wave-guides (96 total) which are stacked poloidally and are symmetric about both the vertical and horizontal planes. The four-stacked arrays are installed through a single equatorial port and can be axially adjusted to provide optimum plasma coupling. Material selections and spatial limitations required innovative design solutions that will be described. C1 Princeton Univ, PPPL, Princeton, NJ 08544 USA. RP Loesser, GD (reprint author), Princeton Univ, PPPL, Princeton, NJ 08544 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 20 EP 22 DI 10.1109/FUSION.2002.1027632 PG 3 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100004 ER PT B AU Kugel, HW Neilson, H Reiersen, W Zarnstorff, M AF Kugel, HW Neilson, H Reiersen, W Zarnstorff, M GP IEEE IEEE TI Neutral beam injection requirements and design issues for the national compact stellarator experiment SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB NCSX will require 6 MW of 50 keV Neutral Beam Injection with initial pulse lengths of 500 msec and upgradeable to pulse lengths of 1.5 sec. This paper discusses the NCSX NBI requirements and design issues, and shows how these are provided by the candidate PBX-M NBI system. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kugel, HW (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 68 EP 71 DI 10.1109/FUSION.2002.1027644 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100016 ER PT B AU Ramakrishnan, S Neumeyer, C Hatcher, R Marsala, R Baker, E Schneider, H Reiersen, W AF Ramakrishnan, S Neumeyer, C Hatcher, R Marsala, R Baker, E Schneider, H Reiersen, W GP IEEE IEEE TI NCSX electrical power systems SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The National Compact Stellarator Experiment (NCSX) is being designed to be built in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). The design of the NCSX electrical power system is tailored to suit the available Infrastructure and electrical equipment on site. The equipment at PPPL is located primarily in two sites called C-Site and D-Site. D-Site houses the majority of electrical equipment. Most of the equipment being used for the currently operating National Spherical Torus Experiment (NSTX) located in D-Site and the earlier Fusion Experimental devices in C-Site, are proposed to be used with suitable modifications to reflect NCSX needs. The NCSX is proposed to be located in C- Site, based on the available Neutral Beam equipment and a Test Cell to house the device. Thus NSTX and NCSX will share some of the available power supplies. The number of circuits and the location of the NCSX device In the C-Site, drove the major changes in the Power system hardware. Only the D-Site power supplies can meet the time response and energy requirements of NCSX. DC power will be transmitted from D-Site to C-Site. The NCSX has a total of nine (9) circuits to be fed from D-Site. Three of the nine circuits are bipolar and the rest are unipolar. Two circuits known as Trim Coils will be fed from the available thyristor power supplies in C-Site. Additional power supplies are available for two more circuits. The hardware needs to be modified to address the requirements of NCSX power loops. The aim is to make the changes in the most cost-effective manner without compromising technical requirements. This paper describes the design changes and addition to the Electrical Power System components for the NCSX magnet system. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Ramakrishnan, S (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 72 EP 75 DI 10.1109/FUSION.2002.1027645 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100017 ER PT B AU Combs, SK Foust, CR Baylor, LR Cole, MJ Fehling, DT Fisher, PW AF Combs, SK Foust, CR Baylor, LR Cole, MJ Fehling, DT Fisher, PW GP IEEE IEEE TI Compact flexible pellet injection system for plasma fueling experiments SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID HIGH-FIELD-SIDE; TECHNOLOGY AB A compact pellet injection system has been designed and constructed at the Oak Ridge National Laboratory to provide a flexible fueling system for studies in in a confinement fusion devices. The system, referred to as a "pellet injector in a suitcase," is a pipe gun device with a four-barrel capability (1- to 4-mm bore), and it uses a cryogenic refrigerator for In-situ hydrogen pellet formation. The injector design allows for simple change-out of barrel sizes and different pellet acceleration options, Including mechanical punches and/or propellant valves to provide speeds in the range of similar to100 to 1500 m/s. The stand-alone instrumentation and controls, as well as the data acquisition system, are personal-computer-based and housed in one standard instrument cabinet. The portable system has been developed to provide a flexible, low-cost fueling system that can be used on a number of plasma confinement experiments with minimal installation and operation costs. The prototype will initially be installed on the Madison Symmetric Torus (MST) at the University of Wisconsin. For the MST application, the pellet sizes will be in the range of 1 to 1.8 mm. C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Combs, SK (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN USA. NR 10 TC 6 Z9 6 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 76 EP 79 DI 10.1109/FUSION.2002.1027646 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100018 ER PT B AU Brunkhorst, C AF Brunkhorst, C GP IEEE IEEE TI Models for automated tube performance calculations SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB High power RF systems, as typically used in fusion research devices, utilize vacuum tubes. Evaluation of vacuum tube performance involves data taken from tube operating curves. The acquisition of data from such graphical sources is a tedious process. A simple modeling method is presented that will provide values of tube currents for a given set of element voltages. These models may be used as subroutines in iterative solutions of amplifier operating conditions for a specific loading impedance. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Brunkhorst, C (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 95 EP 98 DI 10.1109/FUSION.2002.1027651 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100023 ER PT B AU Greenough, N DePasquale, S LaFrance, D AF Greenough, N DePasquale, S LaFrance, D GP IEEE IEEE TI A multi-channel phase detector using programmable logic devices SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB Recent developments in programmable logic devices have led to in-system programming capabilities for FPGA (Field Programmable Logic Array) and CPLD (Complex Programmable Logic Device) devices using inexpensive programming heads and PC-type computers. This development has major advantages for electronic equipment used in a research setting. Many of the devices are electrically erasable and re-programmable hundreds or thousands of times, allowing fast in-system circuit changes or error-correction in the field. This paper describes the successful application of a programmable logic device to a Multi-channel Phase Detector for the HHFW RF systems on NSTX. The Multi-channel Phase Detector is part of a closed-loop phase-control system designed to hold the antenna phase constant regardless of plasma reflections or antenna tuning. The Multi-channel Phase Detector Is a twelve-channel phase measuring device for the High-Harmonic Fast Wave (HHFW) antennas. It is implemented on a circuit board with a CPLD logic device, twelve analog line drivers and optical inputs. Multiple styles of phase detectors have been implemented within the CPLD and their characteristics studied for application to the NSTX HHFW system. Results are shown for a closed-loop phase test using the Multi-channel Phase Detector. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Greenough, N (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 99 EP 102 DI 10.1109/FUSION.2002.1027652 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100024 ER PT B AU Lumia, ME Gentile, CA AF Lumia, ME Gentile, CA GP IEEE IEEE TI Industrial hygiene concerns during the decontamination and decommissioning of the Tokamak Fusion Test Reactor SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB A significant industrial hygiene concern during the Decontamination and Decommissioning (D&D) of the Tokamak Fusion Test Reactor (TFTR) was the oxidation of the lead bricks' surface, which were utilized for radiation shielding. This presented both airborne exposure and surface contamination issues for the workers in the field removing this material. This paper will detail the various protection and control methods tested and implemented to protect the workers including those technologies deployed to decontaminate the work surfaces. In addition, those techniques employed to recycle the lead for additional use at the site will be discussed. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Lumia, ME (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 111 EP 113 DI 10.1109/FUSION.2002.1027655 PG 3 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100027 ER PT B AU Sauthoff, N Navratil, G Bangerter, R AF Sauthoff, N Navratil, G Bangerter, R GP IEEE IEEE TI Snowmass 2002: The fusion energy sciences Summer Study SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The Fusion Summer Study 2002 will be a forum for the critical technical assessment of major next-steps in the fusion energy sciences program, and will provide crucial community input to the long-range planning activities undertaken by the DOE and the FESAC. It will be an ideal place for a broad community of scientists to examine goals and proposed initiatives in burning plasma science in magnetic fusion energy and integrated research experiments in inertial fusion energy. This meeting is open to every member of the fusion energy science community and significant international participation is encouraged. The objectives of the Fusion Summer Study are three: 1. Review scientific issues in burning plasmas to establish the basis for the following two objectives and to address the relations of burning plasma in tokamaks to innovative magnetic ftision energy (MFE) confinement concepts and of ignition in inertial fusion energy (IFE) to integrated research facilities. 2. Provide a forum for critical discussion and review of proposed MFE burning plasma experiments (e.g., IGNITOR, FIRE, and ITER) and assess the scientific and technological research opportunities and prospective benefits of these approaches to the study of burning plasmas. 3. Provide a forum for the IFE community to present plans for prospective integrated research facilities assess present status of the technical base for each, and establish a timetable and technical progress necessary to proceed for each. Based on significant preparatory work by the fusion community prior to the July Snowmass meeting, the Snowmass working groups will prepare a draft report that documents the scientific and technological benefits of studies of burning plasmas. The report will also include criteria by which the benefits of each approach to fusion science, fusion engineering/technology, and the fusion development path can be assessed. Finally, the report will present a uniform technical assessment of the benefits of the three approaches. The draft report will be presented and extensively discussed during the July meeting, leading to a final report. This report will provide critical fusion community input to the decision process of FESAC and DOE in 2002-2003, and to the review of burning plasma science by the National Academy of Sciences called for by FESAC and Energy Legislation which was passed by the House of Representatives [H. R. 4]. Members of the fusion community are encouraged to participate in the Snowmass working groups. C1 Princeton Plasma Phys Lab, DOE, Princeton, NJ USA. RP Sauthoff, N (reprint author), Princeton Plasma Phys Lab, DOE, Princeton, NJ USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 156 EP 158 DI 10.1109/FUSION.2002.1027665 PG 3 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100037 ER PT B AU Gentile, CA Parker, JJ Guttadora, GL Ciebiera, LP AF Gentile, CA Parker, JJ Guttadora, GL Ciebiera, LP GP IEEE IEEE TI Oxidative tritium decontamination system SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The Princeton Plasma Physics Laboratory, Tritium Systems Group has developed and fabricated an Oxidative Tritium Decontamination System (OTDS), which is designed to reduce tritium surface contamination on various components and items. The system is configured to introduce gaseous ozone into a reaction chamber containing tritiated items that require a reduction in tritium surface contamination. Tritium surface contamination (on components and items in the reaction chamber) is removed by chemically reacting elemental tritium to tritium oxide via oxidation, while purging the reaction chamber effluent to a gas holding tank or negative pressure HVAC system. Implementing specific concentrations of ozone along with catalytic parameters [1], the system is able to significantly reduce surface tritium contamination on an assortment of expendable and non-expendable items. This paper will present the results of various experimentation Involving employment of this system [2]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Gentile, CA (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 159 EP 163 DI 10.1109/FUSION.2002.1027666 PG 5 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100038 ER PT B AU Davis, W Roney, P Carroll, T Gibney, T Mastrovito, D AF Davis, W Roney, P Carroll, T Gibney, T Mastrovito, D GP IEEE IEEE TI Web interfaces to MDSplus Data SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The MDSplus Data Acquisition System has been used successfully on NSTX at PPPL since early 1999. While the X-window-based tools supplied with MDSplus are powerful, and both the IDL programming language and the supplied TDI language are effective for complex and specialized analyses, some users prefer the convenience of applications that can be run in a Web browser. Web users don't need to know about X-windows, or even have accounts or privileges on server computers. The MDSplots page reads MDSplus "Scope" setup files and plots MDSplus signals with overlays. It uses a PerI script to open a pipe to an IDL subprocess. The TreeScarch page provides several options for finding information in MDSplus trees. The MDSshots page lists shots where the maximum for a specified signal is above or below a specified value. A variety of information in an MS-SQL database is also accessible from a Web browser. These utilities could be used at other sites which keep data In MDSplus. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Davis, W (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. OI Davis, William/0000-0003-0666-7247 NR 7 TC 2 Z9 2 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 176 EP 179 DI 10.1109/FUSION.2002.1027670 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100042 ER PT B AU Brown, T Nelson, B AF Brown, T Nelson, B GP IEEE IEEE TI Fusion ignition research experiment system integration SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The Fusion Ignition Research Experiment, FIRE, is a high field (10T), relatively modest size tokamak intended to investigate the physics of burning plasmas. The design has been altered in size (slightly), increasing the major radius to 2.14 m from its reference baseline dimension of 2.0 m. The general arrangement and details of the components are not expected to change, but there will be some subtle alterations to address the change in the radial build dimensions of a lower aspect ratio device. The configuration still retains sixteen wedged TF coils that surround a free standing central solenoid, a double wall vacuum vessel and internal plasma facing components that are segmented for maintenance through horizontal ports. Large rings located outside the TF coils are used to obtain a load balance between wedging of the intercoil case structure and wedging at the upper/lower inboard corners of the TF coil winding. The magnets are liquid nitrogen cooled and the entire device is surrounded by a thermal enclosure. The double wall vacuum vessel integrates cooling and shielding in a shape that maximizes shielding of ex-vessel components. First wall tiles are attached directly to inboard and outboard vacuum vessel walls. The divertor is designed for a high triangularity, double-null plasma with a short inner null point-to-wall distance and near vertical outer divertor flux line. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Brown, T (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 188 EP 191 DI 10.1109/FUSION.2002.1027673 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100045 ER PT B AU Young, KM AF Young, KM GP IEEE IEEE TI Challenges for plasma diagnostics in a next step device (FIRE) SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID ITER AB The physics program of any next step tokamak such as FIRE sets demands for plasma measurement which are at least as comprehensive as on present tokamaks, with the additional capabilities needed for control of the plasma and for understanding the effects of the alpha-particles. The diagnostic instrumentation must be able to provide the fine spatial and temporal resolution required for the advanced tokamak plasma scenarios. It must also be able to overcome the effects of neutron- and gamma-induced electrical noise in ceramic components or detectors, and fluorescence and absorption in optical components. There are practical engineering issues of minimizing radiation streaming while providing essential diagnostic access to the plasma. Many diagnostics will require components at or close to the first wall, e.g. ceramics and MI cable for magnetic diagnostics and mirrors for optical diagnostics; these components must be mounted to operate, and survive, in fluxes which require special material selection. A better set of diagnostics of alpha-particles than that available for TFTR is essential; it must be qualified well before moving into D-T experiments. A start has been made to assessing the potential Implementation of key diagnostics for the FIRE device. The present status is described. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Young, KM (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 16 TC 2 Z9 2 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 192 EP 195 DI 10.1109/FUSION.2002.1027674 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100046 ER PT B AU Blanchard, WR Gernhardt, RC Kugel, HW LaMarche, PH AF Blanchard, WR Gernhardt, RC Kugel, HW LaMarche, PH GP IEEE IEEE TI Boronization on NSTX using deuterated trimethylboron SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID DISCHARGE AB Boronization on the National Spherical Torus Experiment (NSTX) has proved to be quite beneficial with increases in confinement and density and decreases in impurities observed in the plasma. The boron has been applied to the interior surfaces of NSTX, about every 2 to 3 weeks of plasma operation, by producing a glow discharge in the vacuum vessel using deuterated trimethylboron (TMB) in a 10% mixture with helium. Special NSTX requirements restricted the selection of the candidate boronization method to the use of deuterated boron compounds. Deuterated TMB met these requirements but is a hazardous gas and special care in the execution of the boronization process is required. This paper describes the existing GDC, Gas Injection, and Torus Vacuum Pumping System hardware used for this process, the glow discharge process, and the automated control system that allows for remote operation to maximize both the safety and efficacy of applying the boron coating. The administrative requirements and the detailed procedure for the setup, operation and shutdown of the process are also described. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Blanchard, WR (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 9 TC 3 Z9 3 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 226 EP 229 DI 10.1109/FUSION.2002.1027681 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100054 ER PT B AU Kalish, M Cropper, M Neumeyer, C Parsells, R Dudek, L Klink, A Morris, L AF Kalish, M Cropper, M Neumeyer, C Parsells, R Dudek, L Klink, A Morris, L GP IEEE IEEE TI Design of the NSTX heating and cooling system SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB NSTX requires that its internal plasma facing components (PFCs) reach 350degreesC during "bakeout" conditioning of the vacuum vessel. This paper describes a helium system designed to meet this requirement as well as provide cooling during plasma operations. The NSTX vacuum vessel's PFCs were designed to be heated or cooled by flowing a fluid medium through tubing attached to the PFC's copper backing plates. The heating / cooling system must move enough fluid at a sufficient rate with a high enough heat capacity through these restrictive paths. After the evaluation of several approaches including the use of heat transfer oils and steam, a compressed helium system was determined to be the optimal choice. The helium system utilizes a blower operating inside of a pressure vessel. This arrangement allows the base pressure to be raised to 20 atmospheres. With the system pressure elevated, the helium blower need only provide the motive force for overcoming 28 psi of friction losses and is not encumbered with compressing the gas. At 20 atmospheres the density of the helium is high enough to provide the heat capacity necessary to meet the NSTX requirements of 66 kW for heating and 82 KW for cooling. The paper will detail the unique design problems associated with a high pressure high temperature helium system as well as review the overall design, and modes of operation. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kalish, M (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 230 EP 233 DI 10.1109/FUSION.2002.1027682 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100055 ER PT B AU Mastrovito, D Blanchard, W Dong, J Gernhardt, R Kugel, H Oliaro, G Provost, T AF Mastrovito, D Blanchard, W Dong, J Gernhardt, R Kugel, H Oliaro, G Provost, T GP IEEE IEEE TI Residual gas analysis hardware and software data acquisition system at NSTX SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The National Spherical Torus Experiment (NSTX) is the first step in an investigation of the physics principles of low-aspect-ratio Spherical Tori (ST) designed to study non-inductive start-up, current sustainability, current profile control, confinement, transport, pressure limits, stability and disruption resilience, as well as unique scrape-off layer (SOL) and Divertor characteristics. NSTX started plasma operations in February 1999. During the first extended period of experiments, plasma discharge reproducibility and performance were strongly affected by impurity control and wall conditions. During this time, Residual Gas Analyzer (RGA) data has been used during non-operating periods and between discharges to measure contributions to the vessel base-pressure (2-3E(-8) Torr) that resulted from impurity gases evolving from internal surfaces. The RGA is a quadrupole mass spectrometer (QMS) with a Faraday Cup and electron multiplier. Recently, a second RGA system was installed to monitor fast changes in impurity gas production during and immediately after plasma discharges, which are indicative of changing conditions. In order to achieve the required response time, scan rates were increased by limiting the range of masses scanned. A data acquisition board was used to drive the new RGA system in concurrence with the NSTX shot cycle. Specialized interactive software to put acquired data into MDSplus, control data acquisition and assist in data analysis was written in Visual Basic and IDL. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Mastrovito, D (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 234 EP 237 DI 10.1109/FUSION.2002.1027683 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100056 ER PT B AU Roney, P Tindall, K Davis, S AF Roney, P Tindall, K Davis, S GP IEEE IEEE TI Computer and network infrastructure of the National Spherical Torus Experiment SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The National Spherical Torus Experiment (NSTX) began acquiring data in February 1999. From the beginning it utilized a heterogeneous collection of computer platforms for control, data acquisition, analysis and security. Computer processing, data acquisition and storage, and network capacity have been subsequently increased. The variety of platforms used for data acquisition and analysis, as well as the number of protocols used on the Ethernet, have also increased. Network capacity has been added to support a growing load of Ethernet-based data acquisition hardware, to handle increased firewall traffic, and to provide bandwidth for visualization of analysis results. Networked video provides broadcast views of the control room and meetings. Four-party video conferencing in the control room allows communication among the members of the national team. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Roney, P (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 238 EP 241 DI 10.1109/FUSION.2002.1027684 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100057 ER PT B AU Sengupta, S Oliaro, G AF Sengupta, S Oliaro, G GP IEEE IEEE TI The NSTX Trouble Reporting System SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB An online Trouble Reporting System (TRS) has been introduced at NSTX. The TRS is used by NSTX operators to report problems that affect NSTX operations. The purpose of the TRS is to enhance NSTX reliability and maintainability by Identifying components, occurrences, and trends that contribute to machine downtime. All NSTX personnel have access to the TRS. The user interface is via a web browser, such as Netscape or Internet Explorer. This web-based feature permits any X-terminal, PC, or MAC access to the TRS. The TRS is based upon a trouble reporting system developed at the DIII-D Tokamak, at General Atomics Technologies [1]. This paper will provide a detailed description of the TRS software architecture, user Interface, MS SQL server interface and operational experiences. In addition, sample data from the TRS database will be summarized and presented. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Sengupta, S (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 242 EP 244 DI 10.1109/FUSION.2002.1027685 PG 3 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100058 ER PT B AU Sichta, P Dong, J AF Sichta, P Dong, J GP IEEE IEEE TI Status of the experimental physics and industrial control system at NSTX SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The NSTX achieved first plasma in 1999. The Experimental Physics and Industrial Control System (EPICS) is used to provide data-integration services for monitoring and control of all NSTX engineering subsystems. EPICS is a set of software initially developed at US DOE laboratories. It is currently used and maintained through a global collaboration of hundreds of scientists and engineers. This paper will relate some of our experiences using and supporting the EPICS software. Topics include reliability and maintainability, lessons learned, recently added engineering subsystems, new EPICS software tools, and a review of our first EPICS software upgrade. Steps to modernize the technical infrastructure of EPICS to ensure effective support for NSTX will also be described. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Sichta, P (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 4 TC 2 Z9 2 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 245 EP 247 DI 10.1109/FUSION.2002.1027686 PG 3 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100059 ER PT B AU Nelson, BE Benson, RD Berry, LA Brooks, AB Cole, MJ Fogarty, PJ Goranson, PL Heitzenroeder, P Hirshman, SP Jones, GH Lyon, JF Mioduszewski, PK Monticello, DA Spong, DA Strickler, DJ Ware, AS Williamson, DE AF Nelson, BE Benson, RD Berry, LA Brooks, AB Cole, MJ Fogarty, PJ Goranson, PL Heitzenroeder, P Hirshman, SP Jones, GH Lyon, JF Mioduszewski, PK Monticello, DA Spong, DA Strickler, DJ Ware, AS Williamson, DE GP IEEE IEEE TI Design of the Quasi-Poloidal Stellarator Experiment (QPS) SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The engineering design status of the Quasi-Poloidal Stellarator Experiment (QPS) is presented. The purpose, configuration, and possible manufacturing and assembly techniques of the various components of the core are described. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Nelson, BE (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. RI Spong, Donald/C-6887-2012 OI Spong, Donald/0000-0003-2370-1873 NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 248 EP 251 DI 10.1109/FUSION.2002.1027687 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100060 ER PT B AU Sheffield, J Batchelor, D Zinkle, S AF Sheffield, J Batchelor, D Zinkle, S GP IEEE IEEE TI Reference scenario for an advanced deuterium power plant system SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID ION-CYCLOTRON RANGE; WAVES AB The proposal is to make large deuterium (D-D) magnetic fusion power plants in which some (most) of the tritium produced by fusion is removed and stored. This tritium will ultimately decay to helium-3 that will be recycled to supplement the helium-3 produced by fusion. Thus the dominant fusion becomes that of deuterium and helium-3. The level of neutron damage is reduced very substantially from that for a DT power plant. C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Sheffield, J (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN USA. OI Zinkle, Steven/0000-0003-2890-6915 NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 252 EP 255 DI 10.1109/FUSION.2002.1027688 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100061 ER PT B AU Sichta, P Oliaro, G Sengupta, S AF Sichta, P Oliaro, G Sengupta, S GP IEEE IEEE TI Upgrade to the tritium remote control and monitoring system for TFTR D&D SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB Since 1988, the Tritium Remote Control and Monitoring System (TRECAMS)[1] has performed crucial functions in support of D-T operations of the Tokamak Fusion Test Reactor (TFTR) [2] at the Princeton Plasma Physics Laboratory (PPPL). Although plasma operations on TFTR were completed in 1907, the need for TRECAMS continued. During this period TRECAMS supported the TFTR tritium systems, the TFTR's Shutdown and Safing phase, and the TFTR Decontamination and Decommissioning (D&D) project. The most critical function of the TRECAMS in the post-TFTR era has been to provide a real-time indication of the airborne tritium levels in the tritium areas and the (HVAC) stacks. TRECAMS Is a critical tool in conducting safe TFTR D&D tritium-line breaks and other tritium-related work activities. Beginning in 1998, the failure rate of the system's hardware sharply increased. Furthermore, the specialized knowledge required to maintain the original software and hardware was diminishing. It soon became apparent that a failure of the TRECAMS could significantly impact the TFTR D&D project's cost and schedule. To preclude this, the TRECAMS hardware and software was upgraded in the year 2000 to use modern components. This paper will describe that successful upgrade, including a review of the engineering processes and our operating experiences with the upgraded system. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Sichta, P (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 260 EP 263 DI 10.1109/FUSION.2002.1027690 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100063 ER PT B AU Kung, C Bernabei, S Gumbas, J Greenough, N Fredd, E AF Kung, C Bernabei, S Gumbas, J Greenough, N Fredd, E GP IEEE IEEE TI Compact probe design for power monitoring from the narrow side of the reduced height waveguide SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID HYBRID AB Due to confined space in a stack of reduced height waveguides, power detection of the incident and reflected wave In the reduced height waveguide is extremely difficult. A new compact probe to monitor the incident and reflected wave from the narrow side of the reduced height waveguide has been developed. This compact probe consists of 2 current loops, a directional coupler, and a small trimmer capacitor. The two current loops are placed on the narrow side of the waveguide with a quarter guide wavelength (lambda(g)/4) spacing. The outputs of the current loops are connected to the directional coupler. In order to optimize phase adjustment, a trimmer capacitor is attached in series with one of the current loops. Test results show that more than 30 dB directivity at 4.6 GHz is achieved by using this compact probe. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kung, C (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 268 EP 271 DI 10.1109/FUSION.2002.1027692 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100065 ER PT B AU Nelson, B Berry, L Brooks, A Brown, T Cole, M Chrznowski, J Dahlgren, F Fan, HM Fogarty, P Goranson, P Heitzenroeder, P Hirshman, S Jones, G Lyon, J Neilson, H Strickler, D Reiersen, WT Williamson, D AF Nelson, B Berry, L Brooks, A Brown, T Cole, M Chrznowski, J Dahlgren, F Fan, HM Fogarty, P Goranson, P Heitzenroeder, P Hirshman, S Jones, G Lyon, J Neilson, H Strickler, D Reiersen, WT Williamson, D GP IEEE IEEE TI Design of the National Compact Stellarator Experiment (NCSX) core SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The design status of the stellarator core for the National Compact Stellarator Experiment (NCSX) is presented. The purpose, configuration, and possible manufacturing and assembly techniques of the various components of the core are described. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Nelson, B (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 285 EP 289 DI 10.1109/FUSION.2002.1027696 PG 5 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100069 ER PT B AU Heitzenroeder, PJ Thome, RJ AF Heitzenroeder, PJ Thome, RJ CA FIRE Engn Team GP IEEE IEEE TI Engineering status and plans for the fusion ignition research experiment (FIRE) SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The FIRE project is being pursued as a possible option for the next step in the US magnetic fusion energy program. Its goal is to develop a compact, high field, highly shaped tokamak with the following parameters: major radius, R, of 2.14 m; minor radius, a, of 0.595 m.; a toroidal field on axis of 10T; a plasma current of 7.7 MA, a flat top time of approximately 20 s, and fusion power of 150 MW. FIRE utilizes liquid nitrogen pre-cooled copper TF and PF magnets. An important goal is a project cost of approximately $1.2B. Initial cost estimates have been produced which indicate FIRE can achieve this cost goal. More detailed cost estimates are planned in FY 02. This paper will give an overview of FIRE's design, discuss the most significant design choices and the background for these choices, and summarizes FIRE's cost estimates and RD plans. C1 Princeton Plasma Phys Lab, Princeton, NJ USA. RP Heitzenroeder, PJ (reprint author), Princeton Plasma Phys Lab, Princeton, NJ USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 296 EP 299 DI 10.1109/FUSION.2002.1027698 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100071 ER PT B AU Kessel, CE Ignat, D Mau, TK AF Kessel, CE Ignat, D Mau, TK GP IEEE IEEE TI Advanced Tokamak scenarios for the FIRE burning plasma experiment SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID NEOCLASSICAL TEARING MODES; HYBRID CURRENT DRIVE; STABILIZATION; STABILITY; SHEAR AB The Advanced Tokamak capability of the FIRE burning plasma experiment is examined with OD systems analysis, equilibrium and ideal MHD stability, RF current drive analysis, and full discharge dynamic simulations. These analyses have identified the required parameters for attractive burning AT plasmas, and indicate that these are feasible with the present progress on existing experimental tokamaks. C1 Princeton Plasma Phys Lab, Princeton, NJ 08534 USA. RP Kessel, CE (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08534 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 301 EP 304 DI 10.1109/FUSION.2002.1027699 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100072 ER PT B AU Schmidt, JA AF Schmidt, JA GP IEEE IEEE TI Fusion implementation SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB If a fusion DEMO reactor can be brought into operation during the first half of this century, fusion power production can have a significant impact on carbon dioxide production during the latter half of the century. An assessment of fusion implementation scenarios shows that the resource demands and waste production associated with these scenarios are manageable factors. If fusion is implemented during the latter half of this century it will be one element of a portfolio of (hopefully) carbon dioxide limiting sources of electrical power. It is time to assess the regional Implications of fusion power implementation. An important attribute of fusion power is the wide range of possible regions of the country, or countries in the world, where power plants can be located. Unlike most renewable energy options, fusion energy will function within a local distribution system and not require costly, and difficult, long distance transmission systems. For example, the East Coast of the United States is a prime candidate for fusion power deployment by virtue of its distance from renewable energy sources. As fossil fuels become less and less available as an energy option, the transmission of energy across bodies of water will become very expensive. On a global scale, fusion power will be particularly attractive for regions separated from sources of renewable energy by oceans. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Schmidt, JA (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 3 TC 0 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 321 EP 323 DI 10.1109/FUSION.2002.1027702 PG 3 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100075 ER PT B AU Majeski, R Antar, G Boaz, M Buchenauer, D Cadwallader, L Causey, R Conn, RW Doerner, R Efthimion, P Finkenthal, M Hoffman, D Jones, B Kaita, R Kugel, H Luckhardt, S Maingi, R Maiorano, M Munsat, T Raftopoulos, S Rognlein, T Spaleta, J Soukhanovskii, V Stutman, D Taylor, G Timberlake, J Ulrickson, M Whyte, D AF Majeski, R Antar, G Boaz, M Buchenauer, D Cadwallader, L Causey, R Conn, RW Doerner, R Efthimion, P Finkenthal, M Hoffman, D Jones, B Kaita, R Kugel, H Luckhardt, S Maingi, R Maiorano, M Munsat, T Raftopoulos, S Rognlein, T Spaleta, J Soukhanovskii, V Stutman, D Taylor, G Timberlake, J Ulrickson, M Whyte, D GP IEEE IEEE TI A toroidal liquid lithium limiter for CDX-U SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB Attention has focused recently on flowing liquid lithium as a first wall for a reactor because of its potentially attractive physics and engineering features. In order to test the suitability of liquid lithium as a plasma facing component, the Current Drive eXperiment - Upgrade (CDX-U) at the Princeton Plasma Physics Laboratory has recently installed a fully toroidal liquid lithium limiter. CDX-U is a compact (R=34cm, a=22 cm, B-toroidal = 2 kG, I-p =100 kA, T-c(0)similar to100 eV, n(c)(0)similar to 5 X 10(19) m(-3)) short-pulse (<25 msec) spherical torus (ST) with extensive diagnostics. The limiter, which consists of a shallow circular stainless steel tray of radius 34 cm and width 10 cm, is filled with lithium to a depth of a few millimeters, and forms the lower limiting surface for the discharge. Heating elements beneath the tray are used to liquefy the lithium (melting point = 180.5degrees C) prior to the experiment. The total area of liquid lithium exposed to the plasma is approximately 2000 cm(2). The design of the limiter, modifications to CDX-U to accommodate in-vessel inventories of approximately 1 liter of liquid lithium, techniques for loading lithium onto the limiter, and other preparations will be described. CDX-U has previously been successfully operated with a smaller area (300 cm(2)) liquid lithium rail limiter. Diagnostics specific to lithium operations include muItichord spectrometry of the 135 Angstrom LiIII line in the core plasma, monitors for neutral lithium light at the lithium limiter, and a fast (10,000 frame per second) camera which monitors motion of the liquid during the discharge. First results of plasma operations with the toroidal liquid lithium limiter will also be given. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. RP Majeski, R (reprint author), Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. RI Stutman, Dan/P-4048-2015 NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 341 EP 344 DI 10.1109/FUSION.2002.1027707 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100080 ER PT B AU Nygren, RE Youchison, DL Kim, J Im, KH Kim, KS Park, HC AF Nygren, RE Youchison, DL Kim, J Im, KH Kim, KS Park, HC GP IEEE IEEE TI High heat flux tests of carbon composites for KSTAR and NSTX SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID TOKAMAK AB Uncooled samples of various carbon fiber composites (CFCs), nominally 2.50 cm square and 1.00 cm in height were exposed in the Electron Beam Test System (EBTS) to heat fluxes up to similar to100MW/m(2) for shots typically of 1.5s. The heat flux was focused on a square I x I cm at the center of the sample. For NSTX (National Spherical Torus Experiment), five samples of Allied Signal 2-D CFC Type 865-19-4 were tested with 1.5s shots at heat fluxes to 120MW/m(2). For KSTAR (Korean Superconducting Tokamak Advanced Research) Project, a total of 37 samples of 29 various CFCs were tested. Duplicates samples with thermocouples were used to measure the absorbed heat and to calculate the fraction of the beam power absorbed. The samples were tested to 100MW/m(2) with 1.5s shots and then selected samples were tested at 60MW/m(2) for shots up to 3.5s. The most basic results from all of these tests is that, as expected, none of the samples fractured. For the KSTAR test, some samples achieved higher heat fluxes than others while their surface temperatures remained below a threshold of 2800degreesC. Other observations presented in the paper are based on post-test examinations of the surface morphologies. The paper was presented in poster form at SOFE99 but not published there and is represented here. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Nygren, RE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. OI Youchison, Dennis/0000-0002-7366-1710 NR 4 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 345 EP 347 DI 10.1109/FUSION.2002.1027708 PG 3 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100081 ER PT B AU Youchison, DL Nygren, RE O'Dell, JS McDonald, JM Lutz, TJ AF Youchison, DL Nygren, RE O'Dell, JS McDonald, JM Lutz, TJ GP IEEE IEEE TI Advances in tungsten-armored plasma facing components SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB High-Z armor is appropriate for use on plasma facing components (pfcs) subjected to very high heat loads and low plasma edge temperatures. During the past several years much progress was made on the development of tungsten rod armor bonded to water-cooled heatsinks. These pfcs can endure heat fluxes near 25 MW/m(2) typical of high density burning plasmas without thermal stress cracking, melting or debonding of the armor. Tungsten rod armor is considered for use on portions of the ITER-FEAT divertor and is the reference design for the FIRE divertor. This year, three 40-cm-long, dual-channel, water-cooled, tungsten rod-armored pfc mock-ups were fabricated by Plasma Processes, Inc. and tested at the Plasma Materials Test Facility at Sandia National Laboratories. The 32 mm-wide armor was fabricated by plasma spraying copper onto the back of a hexagonal close-packed array of 3-mm-diameter tungsten welding rods with an exposed height of 10 mm. In one of the mock-ups, designated PW-8, the armor was joined to a copper heat sink by hot isostatic pressing using a Ni interlayer. In another type of mock-up, designated PW-14, full-penetration electron beam welding was used to join the tungsten and plasma-sprayed copper substrate to the heatsink. The mock-ups were tested with 4 MPa, 20 degreesC water at 15 m/s using a rastered electron beam system. The highest absorbed heat flux, 24 MW/m(2) over a 10-cm heated length, brought the rod ends to the melting point. Fabrication issues, thermal fatigue performance at 20 MW/m(2), and the results of surface analyses of the rods also are reported. These test results help qualify the pfc design for use in the FIRE divertor. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Youchison, DL (reprint author), Sandia Natl Labs, POB 5800,MS-1129, Albuquerque, NM 87185 USA. OI Youchison, Dennis/0000-0002-7366-1710 NR 11 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 364 EP 367 DI 10.1109/FUSION.2002.1027713 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100086 ER PT B AU Kaita, R Jardin, S Jones, B Kessel, C Majeski, R Spaleta, J Woolley, R Zakharov, L Nelson, B Ulrickson, M AF Kaita, R Jardin, S Jones, B Kessel, C Majeski, R Spaleta, J Woolley, R Zakharov, L Nelson, B Ulrickson, M GP IEEE IEEE TI Modeling of spherical torus Plasmas for liquid lithium wall experiments SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID TOKAMAKS AB Liquid metal walls have the potential solve to first-waIl problems for fusion reactors, such as heat load and erosion of dry walls, neutron damage and activation, and tritium inventory and breeding. In the near term, such walls can serve as the basis for schemes to stabilize magnetohydrodynamic (MHD) modes. Furthermore, the low recycling characteristics of lithium walls can be used for particle control. Liquid lithium experiments have already begun in the Current Drive eXperiment-Upgrade (CDX-U). Plasmas limited with a toroidally localized limiter have been investigated, and experiments with a fully toroidal lithium limiter are in progress. A liquid surface module (LSM) has been proposed for the National Spherical Torus Experiment (NSTX). In this larger ST, plasma currents are in excess of 1 MA and a typical discharge radius is about 68 cm. The primary motivation for the LSM is particle control, and options for mounting it on the horizontal midplane or in the divertor region are under consideration. A key consideration is the magnitude of the eddy currents at the location of a liquid lithium surface. During plasma start up and disruptions, the force due to such currents and the magnetic field can force a conducting liquid off of the surface behind it. The Tokamak Simulation Code (TSC) has been used to estimate the magnitude of this effect. This program is a two dimensional, time dependent, free boundary simulation code that solves the MHD equations for an axisymmetric toroidal plasma. From calculations that match actual ST equilibria, the eddy current densities can be determined at the locations of the liquid lithium. Initial results have shown that the effects could be significant, and ways of explicitly treating toroidally local structures are under investigation. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. RP Kaita, R (reprint author), Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. NR 9 TC 1 Z9 1 U1 1 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 368 EP 371 DI 10.1109/FUSION.2002.1027714 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100087 ER PT B AU Bromberg, L Brown, T Dahlgren, F Heitzenroeder, P AF Bromberg, L Brown, T Dahlgren, F Heitzenroeder, P GP IEEE IEEE TI ARIES-AT magnet systems SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB This paper presents a conceptual design of the magnet systems for an advanced tokamak fusion reactor (ARIES-AT). The main emphasis of the paper is the extrapolation of the current state-of-the-art in high temperature superconductors and coil design, and their implementation in an advanced commercial fusion reactor concept. A conceptual design of both the poloidal field coils and toroidal field coils is presented. The current design point is described and supported with a preliminary structural analysis and a discussion of the merits, performance, and economics of high temperature vs. low temperature superconductors in an advanced fusion reactor design. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Bromberg, L (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 404 EP 408 DI 10.1109/FUSION.2002.1027723 PG 5 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100096 ER PT B AU Neumeyer, C Heitzenroeder, P Kessel, C Ono, M Peng, M Schmidt, J Woolley, R Zatz, I AF Neumeyer, C Heitzenroeder, P Kessel, C Ono, M Peng, M Schmidt, J Woolley, R Zatz, I GP IEEE IEEE TI Spherical torus center stack design SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The low aspect ratio spherical torus (ST) configuration requires that the center stack design be optimized within a limited available space, using materials within their established allowables. This paper presents certer stack design methods developed by the National Spherical Torus Experiment (NSTX) Project Team during the initial design of NSTX, and more recently for studies of a possible next step ST (NSST) device. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08544 USA. RP Neumeyer, C (reprint author), Princeton Univ, Plasma Phys Lab, Princeton, NJ 08544 USA. NR 8 TC 1 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 413 EP 417 DI 10.1109/FUSION.2002.1027725 PG 5 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100098 ER PT B AU Williamson, D Brooks, A Cole, M Fan, HM Fogarty, P Nelson, B Strickler, D Reiersen, W AF Williamson, D Brooks, A Cole, M Fan, HM Fogarty, P Nelson, B Strickler, D Reiersen, W GP IEEE IEEE TI Design and analysis of the modular coils for the National Compact Stellarator Experiment (NCSX) SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The National Compact Stellarator Experiment (NCSX) is proposed as a test of a low aspect ratio, quasi-axisymmetric plasma configuration that exhibits high beta and good confinement in a disruption-free environment. The experiment will be built at Princeton Plasma Physics Laboratory (PPPL) and utilize some ancillary equipment. The NCSX stellarator core is a complex assembly of four coil systems which provide magnetic field for plasma shaping and position control, inductive current drive, and field error correction. The primary magnets are the modular coils, which provide up to 2-T at an average major radius of 1.4-m. Other magnets include toroidal field (TF) coils, poloidal field (PF) coils, and trim coils, which can be used to control resonant field errors. The magnets are supported by an integral shell structure, which also serves as the winding form for the modular coils. The coils and structure have been evaluated for thermal stress and electromagnetic loads during normal operating conditions. The results indicate that the performance of the modular coil system is acceptable. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Williamson, D (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 418 EP 421 DI 10.1109/FUSION.2002.1027726 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100099 ER PT B AU Raftopoulos, S Barnes, G Chrzanowski, J DiMattia, J Fedder, R Gallagher, D Gilsenan, E Gettelfinger, G Jakober, R Laneski, J LaMarche, P Lindenberg, R Parsells, R Perry, E Rule, K Semler, J Stacy, J Viola, M Zatz, I Zimmer, W AF Raftopoulos, S Barnes, G Chrzanowski, J DiMattia, J Fedder, R Gallagher, D Gilsenan, E Gettelfinger, G Jakober, R Laneski, J LaMarche, P Lindenberg, R Parsells, R Perry, E Rule, K Semler, J Stacy, J Viola, M Zatz, I Zimmer, W GP IEEE IEEE TI Overview of the TFTR D&D program SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The Tokamak Fusion Test Reactor (TFTR) operated for 15 years, from 1982 to 1997. From November 1993 to April 1997 a mixture of Deuterium-Tritium (D-T) was used to fuel experiments, leaving the reactor system in an activated and contaminated state. In this condition, the removal of the TFTR and its subsystems is greatly complicated. In 1999, PPPL commenced the TFTR Decontamination and Decommissioning (D&D) Project. The objectives of the D&D projects are to completely remove the TFTR in a safe, efficient and cost effective manner. To date all diagnostics, structural components and ancillary systems have been removed, and the tokamak is in the process of being sectioned into smaller pieces. This paper will describe the criteria, the methods employed and the successes of the DD Project. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Raftopoulos, S (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 465 EP 468 DI 10.1109/FUSION.2002.1027736 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100109 ER PT B AU Skinner, CH Gentile, CA Hassanein, A AF Skinner, CH Gentile, CA Hassanein, A GP IEEE IEEE TI High heat flux interactions and tritium removal from plasma facing components by a scanning laser SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID INSTABILITIES; EROSION AB A new technique for studying high heat flux interactions with plasma facing components is presented. The beam from a continuous wave 300 W neodymium laser was focussed to 80 W/mm(2) and scanned at high speed over the surface of carbon tiles. These tiles were previously used in the TFTR inner limiter and have a surface layer of amorphous hydrogenated carbon that was codeposited during plasma operations. Laser scanning released up to 84% of the coideposited tritium. The temperature rise of the codeposit on the tiles was significantly higher than that of the manufactured material. In one experiment, the codeposit surface temperature rose to 1,770 degreesC while for the same conditions, the manufactured surface increased to only 1,080 degreesC. The peak temperature did not follow the usual square-root dependence on heat pulse duration. Durations of order 100 ms resulted in brittle destruction and material loss from the surface, while a duration of approximate to10 ms showed minimal change. A digital microscope imaged the codeposit before, during and after the interaction with the laser and revealed hot spots on a 100-micron scale. These results will be compared to analytic modeling and are relevant to the response of plasma facing components to disruptions and vertical displacement events (VDEs) in next-step magnetic fusion devices. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Skinner, CH (reprint author), Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. NR 25 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 473 EP 476 DI 10.1109/FUSION.2002.1027738 PG 4 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100111 ER PT B AU Zinkle, SJ Kohyama, A AF Zinkle, SJ Kohyama, A GP IEEE IEEE TI Advanced materials for fusion energy SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE/NPSS Symposium on Fusion Engineering CY JAN 21-25, 2001-2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc ID CHROMIUM-TUNGSTEN STEELS; RESEARCH-AND-DEVELOPMENT; VANADIUM ALLOYS; FRACTURE-TOUGHNESS; SIC/SIC COMPOSITES; STRUCTURAL APPLICATIONS; NEUTRON-IRRADIATION; CRITICAL-ISSUES; BASE ALLOYS; SYSTEMS AB An overview is given regarding recent work on the development of advanced structural and nonstructural materials for fusion reactors. In particular, research highlights are presented on advanced ferritic/martensitic steels, V alloys, Mo alloys, and Sic composites, which are candidate structural materials for fusion systems. The potential for developing improved high-strength, high-conductivity Cu alloys for normal conducting magnets and divertor structures is assessed. The current status of several key nonstructural materials systems (including insulators and optical materials) is also summarized. C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Zinkle, SJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN USA. OI Zinkle, Steven/0000-0003-2890-6915 NR 45 TC 4 Z9 4 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 477 EP 483 DI 10.1109/FUSION.2002.1027739 PG 7 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100112 ER PT B AU Waldron, W Logan, B Ahle, L Sabbi, G AF Waldron, W Logan, B Ahle, L Sabbi, G GP IEEE IEEE TI Engineering and enabling technology development for heavy ion fusion drivers SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The Heavy Ion Fusion Virtual National Laboratory is a collaboration among LBNL, LLNL, and PPPL. The engineering and technology development activities are closely aligned with the major experimental areas, which include injectors, beam transport, and final focus. High current density ion sources to produce a more compact multiple beam injector are a major focus of the current activities. There are several collaborations with insulator manufacturers to achieve higher gradients while lowering the manufacturing cost and maintaining high vacuum compatibility. Solid-state pulser technology is being pursued through an SBIR contract to provide reliable pulsers with agile waveform control, a required capability to compress the beam and correct for space charge effects. Ferromagnetic material development is continuing to look at low-loss, high flux swing material that is affordable. The testing of prototype pulsed and superconducting magnets over the last year has provided the basis for developing both of these magnet systems for the present single beam experiments. A heavy ion fusion driver will require continued technology development in these areas to meet the required performance goals and remain economically feasible. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Waldron, W (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 484 EP 486 DI 10.1109/FUSION.2002.1027740 PG 3 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100113 ER PT B AU Moses, EI AF Moses, EI GP IEEE IEEE TI The national ignition facility: Status and plans for laser fusion and high-energy-density experimental studies SO 19TH IEEE/NPSS SYMPOSIUM ON FUSION ENGINEERING, PROCEEDINGS LA English DT Proceedings Paper CT 19th Symposium on Fusion Engineering (SOFE) CY JAN 21, 2001-JAN 25, 2002 CL ATLANTIC CITY, NJ SP IEEE, Nucl & Plasma Sci Soc AB The National Ignition Facility (NIF), currently under construction at the University of California's Lawrence Livermore National Laboratory is a $2.2513 stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, 351-nm laser system. NIF is being built by the National Nuclear Security Agency and when completed will be the world's largest laser system, providing a national center to study inertial confinement fusion and the physics of extreme energy densities and pressures. In NIF up to 192 energetic laser beams will compress small fusion targets to conditions where they will ignite and burn, liberating more energy than is required to initiate the fusion reactions. NIF experiments will allow the study of physical processes at temperatures approaching 100 million K and 100 billion times atmospheric pressure. These conditions exist naturally only in the interior of stars and in nuclear weapons explosions. In the course of designing the world's most energetic laser system, a number of significant technology breakthroughs have been achieved. Research is also underway to develop a shorter pulse capability on NIF for high power applications. We discuss here the technology challenges and solutions that have made NIF possible along with enhancements to NIF's design that could lead to exawatt power levels. C1 Lawrence Livermore Natl Lab, Livermore, CA USA. RP Moses, EI (reprint author), Lawrence Livermore Natl Lab, Livermore, CA USA. NR 0 TC 1 Z9 1 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7073-2 PY 2002 BP 487 EP 492 DI 10.1109/FUSION.2002.1027741 PG 6 WC Nuclear Science & Technology; Physics, Fluids & Plasmas SC Nuclear Science & Technology; Physics GA BV03T UT WOS:000177665100114 ER PT B AU Rivetta, C Allongue, B Berger, G Faccio, F Hajdas, W AF Rivetta, C Allongue, B Berger, G Faccio, F Hajdas, W GP IEEE IEEE TI Single event burnout in DC-DC converters for the LHC experiments SO 2001 6TH EUROPEAN CONFERENCE ON RADIATION AND ITS EFFECTS ON COMPONENTS AND SYSTEMS LA English DT Proceedings Paper CT 6th European Conference on Radiation and Its Effects on Components and Systems CY SEP 10-14, 2001 CL GRENOBLE, FRANCE SP Techn Informat & Microelectr Comp Architecture Lab, RADECS Assoc, IEEE Nucl & Plasma Sci Soc ID POWER MOSFETS; MECHANISM AB High voltage transistors in DC-DC converters are prone to catastrophic Single Event Burnout in the LHC radiation environment. This paper presents a systematic methodology to analyze single event effects sensitivity in converters and proposes solutions based on de-rating input voltage and output current or voltage. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Rivetta, C (reprint author), Fermilab Natl Accelerator Lab, POB 500,MS222, Batavia, IL 60510 USA. EM rivetta@fnal.gov; andre.allongue@cern.ch; Federico.Faccio@cern.ch NR 16 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7313-8 PY 2002 BP 315 EP 322 DI 10.1109/RADECS.2001.1159300 PG 8 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Nuclear Science & Technology; Optics SC Engineering; Instruments & Instrumentation; Nuclear Science & Technology; Optics GA BV99V UT WOS:000180627900050 ER PT S AU Drozda, M AF Drozda, M GP IEEE IEEE IEEE IEEE TI Electric power exchanges with sensitivity matrices - An experimental analysis SO 2001 IEEE INTERNATIONAL CONFERENCE ON SYSTEMS, MAN, AND CYBERNETICS, VOLS 1-5: E-SYSTEMS AND E-MAN FOR CYBERNETICS IN CYBERSPACE SE IEEE INTERNATIONAL CONFERENCE ON SYSTEMS, MAN, AND CYBERNETICS, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Systems, Man and Cybernetics (SMC) CY OCT 07-10, 2001 CL TUCSON, AZ SP IEEE, Raytheon AB We describe a fast incremental method for power flows computation tailored for electric power markets. Fast in the sense that it can be used for real time power flows computation, and incremental in the sense that it computes any additional increase/decrease in line congestion caused by a particular (n-lateral) contract. Incremental methods offer a powerful way of dealing with congestion contingency, improve information flows among market entities, and are easy to understand. In this document we provide basic scaling properties for electric power markets using this method, and compare it with methods using (linearized) power flow code. The author is in the process of obtaining a patent on methods, algorithms, and procedures described in this paper. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Drozda, M (reprint author), Los Alamos Natl Lab, POB 1663,MS M997, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1062-922X BN 0-7803-7087-2 J9 IEEE SYS MAN CYBERN PY 2002 BP 1942 EP 1947 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BU92K UT WOS:000177404200338 ER PT S AU Wilson, DG Robinett, RD AF Wilson, DG Robinett, RD GP IEEE IEEE IEEE IEEE TI Robust adaptive backstepping control for a nonholonomic mobile robot SO 2001 IEEE INTERNATIONAL CONFERENCE ON SYSTEMS, MAN, AND CYBERNETICS, VOLS 1-5: E-SYSTEMS AND E-MAN FOR CYBERNETICS IN CYBERSPACE SE IEEE International Conference on Systems Man and Cybernetics Conference Proceedings LA English DT Proceedings Paper CT IEEE International Conference on Systems, Man and Cybernetics (SMC) CY OCT 07-10, 2001 CL TUCSON, AZ SP IEEE, Raytheon DE mobile robots; robust adaptive control; backstepping ID TRACKING CONTROL AB This paper introduces a robust adaptive control architecture for nonholonomic mobile robots. The concept of backstepping provides a bridge between the kinematics and dynamics. In previous work normally only the vehicle steering, dependent upon the kinematics are considered for vehicle control. Improved tracking performance is achieved by including vehicle dynamics and robustness compensation for variances in parameters. Numerical simulations demonstrate the effectiveness of the robust adaptive control algorithm. C1 Sandia Natl Labs, Intelligent Syst Sensors & Controls Dept, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Intelligent Syst Sensors & Controls Dept, MS 1003, Albuquerque, NM 87185 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1062-922X BN 0-7803-7087-2 J9 IEEE SYS MAN CYBERN PY 2002 BP 3241 EP 3245 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BU92K UT WOS:000177404200571 ER PT S AU Bebek, C Groom, D Holland, S Karcher, A Kolbe, W Lee, J Levi, M Palaio, N Turko, B Uslenghi, M Wagner, M Wang, G AF Bebek, C Groom, D Holland, S Karcher, A Kolbe, W Lee, J Levi, M Palaio, N Turko, B Uslenghi, M Wagner, M Wang, G BE Seibert, JA TI Proton radiation damage in p-channel CCDs fabricated on high-resistivity silicon. SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc DE CCD; high resistivity silicon; radiation damage AB P-channel, backside illuminated silicon CCDs were developed and fabricated on high-resistivity n-type silicon. Devices have been exposed up to 1 x 10(11) protons/cm(2) at 12 MeV. The charge transfer efficiency and dark curent were measured as a function of radiation dose. These CCDs were found to be significantly more radiation tolerant than conventional n-channel devices. This could prove to be a major benefit for long duration space missions. C1 Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Bebek, C (reprint author), Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Holland, Stephen/H-7890-2013 NR 10 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 72 EP 75 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800016 ER PT S AU Hall, BK Appel, JA Cardoso, G Christian, D Hoff, J Kwan, S Mekkaoui, A Yarema, R Zimmermann, S AF Hall, BK Appel, JA Cardoso, G Christian, D Hoff, J Kwan, S Mekkaoui, A Yarema, R Zimmermann, S BE Seibert, JA TI Development of a readout technique for the high data rate BTeV pixel detector at Fermilab SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB The pixel detector for the BTeV experiment at Fermilab provides digitized data from approximately 22 million silicon pixel channels. Portions of the detector are six millimeters from the beam providing a substantial hit rate and high radiation dose. The pixel detector data will be employed by the lowest level trigger system for track reconstruction every beam crossing. These requirements impose a considerable constraint on the readout scheme. This paper presents a readout technique that provides the bandwidth that is adequate for high hit rates, minimizes the number of radiation hard components, and satisfies all other design constraints. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Hall, BK (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 90 EP 93 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800020 ER PT S AU Kim, JG Dardin, SM Jackson, KH Kadel, RW Kadyk, JA Peskov, V Wenzel, WA AF Kim, JG Dardin, SM Jackson, KH Kadel, RW Kadyk, JA Peskov, V Wenzel, WA BE Seibert, JA TI Studies of electron avalanche behavior in liquid argon SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID CHAMBER; XENON AB Electron avalanching in liquid argon is being studied as a function of voltage, pressure, radiation intensity, and the concentrations of certain additives, especially xenon. The avalanches produced in an intense electric field at the tip of a tungsten needle are initiated by ionization from a moveable americium (Am-241) gamma ray source. Photons from xenon excimers are detected as photomultiplier signals in coincidence with the current pulse from the needle. In pure liquid argon the avalanche behavior is erratic, but the addition of even a small amount of xenon (less than or equal to100ppm) stabilizes the performance. Similar attempts with neon (30%) as an additive to argon have been unsuccessful. Tests with higher energy gamma rays (Co-57) yield spectra and other performance characteristics quite similar to those using the Am-241 source. Two types of signal pulses are commonly observed: a set of pulses that are sensitive to ambient pressure, and a set of somewhat smaller pulses that are not pressure dependent. C1 Lawrence Berkeley Natl Lab, Phys Div, Berkeley, CA 94720 USA. RP Kim, JG (reprint author), Lawrence Berkeley Natl Lab, Phys Div, Berkeley, CA 94720 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 119 EP 123 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800027 ER PT S AU De Geronimo, G Kandasamy, A O'Connor, P AF De Geronimo, G Kandasamy, A O'Connor, P BE Seibert, JA TI Analog peak detector and derandomizer for high rate spectroscopy SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID HOLD CIRCUIT; CMOS AB A compact and accurate readout system has been developed for high-rate spectroscopy with multi-element detectors. The fully self-triggered system multiplexes the signals from 32 detectors into a novel peak detector, which also serves as a derandomizer. The captured pulse heights are stored as analog samples before being presented to the ADC along with the corresponding channel addresses. The peak detector incorporates a new two-phase configuration that cancels offsets and other errors found in conventional designs. Offset cancellation gives the peak detector rail-to-rail sensing and driving capability, and permits two or more peak detectors to be operated in parallel to serve as a data-driven analog memory. First experimental results on the new peak detector and derandomizer (PDD) circuit, fabricated in 0.35 mum CMOS technology, include a 0.2 % absolute accuracy for pulses with 500 ns peaking time, 2.7 V linear input range, 3.5 mW power dissipation, 250 mV/s droop rate, and negligible dead time. We have tested the system with 32 CZT detectors and a Am-241 source. The spectra collected from the 32-channel system show that the noise performance of the preamp/shaper is not degraded by the multiplexing, peak detecting, and derandomizing operations. C1 Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. RP De Geronimo, G (reprint author), Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 147 EP 150 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800033 ER PT S AU Li, Z Abreu, M Eremin, V Granata, V Mariano, J Mendes, PR Niinikoski, TO Sousa, P Verbitskaya, E Zhang, W AF Li, Z Abreu, M Eremin, V Granata, V Mariano, J Mendes, PR Niinikoski, TO Sousa, P Verbitskaya, E Zhang, W BE Seibert, JA TI Electrical and TCT characterization of edgeless Si detectors diced with different methods SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID SILICON DETECTORS AB High-resistivity p(+)/n/n(+) Si pad detectors (0.25 cm(2)) were diced, using different dicing tools and methods, into a shape having on one edge no dead space ("edgeless detectors"). The dicing was extended into the sensitive area of the front p(+) implant. Two different dicing tools were used: laser cutting and scribing. Dicing methods included cutting from the front p(+) side and from the back n(+) side. It was found that, with no chemical or aging treatment of edges cut in this way, all the detectors (diced with different tools and methods) suffered from a very high leakage current of hundreds of muA's to mA at full depletion voltage (V-fd), as compared with a few nA before dicing, when measured the same day after dicing. All such detectors showed breakdown just at or near Vfd similar to 80-100 V. However, after one day of room temperature aging in air, the leakage currents at V-fd improved dramatically to 1-2 muA if diced (laser cutting and scribing) from the backside. Also there was no breakdown up to 500 V. There was little improvement over time if the sensor was diced from the front side. After at least one day of aging, detectors diced from the backside showed normal C-V and charge collection behavior. Nevertheless, the remaining leakage seems to be dominated by surface current and shows little improvement at temperatures down to 130 K. Chemical treatment, though, is promising for further reduction of the surface current < 1 muA at V-fd and < 10 muA at 500 V. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Li, Z (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Rato Mendes, Pedro/F-8827-2010; Verbitskaya, Elena/D-1521-2014 OI Rato Mendes, Pedro/0000-0001-9929-0869; NR 5 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 202 EP 206 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800045 ER PT S AU Burks, MT Amman, M Boggs, SE Hull, EL Luke, PN Madden, NW Riot, VJ Ziock, KP AF Burks, MT Amman, M Boggs, SE Hull, EL Luke, PN Madden, NW Riot, VJ Ziock, KP BE Seibert, JA TI A germanium gamma ray imager with 3-D position sensitivity SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB A germanium based gamma ray imager with 3-D position sensitivity is being developed. The imager will detect gamma rays in the range of similar to10 keV to 1.5 MeV and locate their interactions in the germanium to within 2 mm in X, Y and Z. The instrument is segmented into 39 orthogonal strips in both the X and Y directions with a 2 mm pitch. Each channel is separately instrumented with a miniature low-noise charge-sensitive preamplifier followed by shaping and timing electronics. Germanium based imagers with 2-D position sensitivity have recently been developed and fully instrumented by our group. The current instrument adds the capability for determining the Z position (depth of interaction). The Z coordinate is found by looking at the relative timing of the signals induced by the drifting electrons and holes. A relatively simple analog approach for determining the depth of interaction was implemented. Some of the intended applications for this type of instrument include balloon based imaging experiments and field portable devices for environmental remediation. Therefore, much of the effort was concentrated on developing a detector and electronics scheme that was simple, compact, and low power. The instrument is described with emphasis on the technique used for measuring the Z coordinate. Results obtained from spectroscopy as well as z position measurements are shown. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Burks, MT (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Boggs, Steven/E-4170-2015 OI Boggs, Steven/0000-0001-9567-4224 NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 223 EP 225 PG 3 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800050 ER PT S AU Aryaeinejad, R Reber, EL Spencer, DF AF Aryaeinejad, R Reber, EL Spencer, DF BE Seibert, JA TI Handheld device for simultaneous monitoring of fast neutrons and gamma rays SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID DISCRIMINATION AB Currently at the INEEL, a handheld device is being developed to measure fast neutrons and gamma rays using a single detector instead of a previous two detector system. The handheld detection system presented here uses a single 1/2 inch (diameter) by 1/2 inch (long) liquid scintillator detector (BC501). This means the detection system can be made smaller, lighter, less expensive, and is expected to be more sensitive than the original system. A smaller and lighter device makes it possible to be used in several applications such as customs inspection, border security, environmental radiation monitoring, and so on. The use of only one detector requires that the neutrons and gamma rays be distinguished by the shape of their pulses in the detector. Two methods of pulse shape discrimination (PSD) are: presented here, charge integration and crossover timing. Figures of merit were calculated for both methods for a threshold energy range of 50 to 600 keV. Results show that the crossover method gives much better PSD for electron energy of 100 keV and lower, whereas the charge integration method leads to better separation above 100 keV. However, the neutrons and gamma rays are totally separated for energies of 100 keV and above in both techniques. We are currently designing a miniaturized electronic system to be incorporated in the handheld device. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Aryaeinejad, R (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 385 EP 388 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800086 ER PT S AU Rawool-Sullivan, MW Sullivan, JP Koster, JE Rooney, BD AF Rawool-Sullivan, MW Sullivan, JP Koster, JE Rooney, BD BE Seibert, JA TI Validity and limitations of the three plane Compton imaging technique via simulations SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID CAMERA; TELESCOPE AB Gamma imaging based on Compton scattering was first proposed approximately 25 years ago as a replacement for mechanically collimated imaging systems. The advantages of such instruments over mechanically collimated systems are a wider field of view, higher efficiency (more source photons are used in the image construction), source localization, use in high-background environments, and non-tomographic three-dimensional imaging of near-field sources. One can also image multi-energy photons by selecting events based on the summed energy deposited in multiple detectors. The traditional example of such imaging systems is a Compton camera. Until recently, limitations with associated hardware have resulted in Compton imaging seeing few applications. However, with advances in high spatial resolution detectors, and further developments in the physical principles there has been a renewed interest in gamma imaging based on Compton scattering in many areas including astronomy and nuclear medicine. In this paper we present an evaluation of a three plane Compton imaging concept referred to in this paper as the three plane Compton imaging technique. Such a technique, if valid, could lead to many useful applications. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Rawool-Sullivan, MW (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 389 EP 393 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800087 ER PT S AU Ahn, SK Kim, JG Perez-Mendez, V Chang, S Jackson, KH Kadyk, JA Wenzel, WA Cho, G AF Ahn, SK Kim, JG Perez-Mendez, V Chang, S Jackson, KH Kadyk, JA Wenzel, WA Cho, G BE Seibert, JA TI GEM-type detectors using LIGA and etchable glass technologies SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID GAS AB Gas electron multipliers (GEMS) have been made by a deep X-ray lithography technique (LIGA process) using synchrotron radiation on polymethylmethacrylate (PMMA) and by UV processes using a UV etchable glass. Gain, stability and rate capability for these detectors are described. The LIGA detectors described consist of PMMA sheets of various thicknesses, 125mum to 350mum, and have 150mum x 150mum square holes spaced with a pitch of 300mum. Thin copper electrodes are plated on the top and bottom surfaces using a Damascene method, followed by electroless plating of the copper onto a palladium-tin base layer. For various thicknesses of PMMA measurements have been made of absolute gain vs. voltage, time stability of gain, and rate capability. The operating gas mixture was usually Ar/CO2 (70/30) gas, but some tests were also done using P10 gas. We also made GEM-like detectors using the UV etchable glass called Foturan, patterned by exposure to UV light and subsequent etching. A few measurements using these detectors will be reported, including avalanche gain and time stability. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. RP Ahn, SK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 467 EP 471 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800104 ER PT S AU Aalseth, CE Bowyer, SM Reeder, PL AF Aalseth, CE Bowyer, SM Reeder, PL BE Seibert, JA TI Radiation discrimination in LiBaF3 scintillator using digital signal processing techniques SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID THERMAL-NEUTRON SCINTILLATOR; CRYSTALS AB Pulse analysis techniques with the scintillator LiBaF3:Ce allow very clean separation of densely ionizing radiation (protons, deuterons, tritons, alphas, etc.) from less densely ionizing radiation (electrons). Consequently, pulse height spectra for each type of radiation can be obtained simultaneously. The pulse discrimination is based on the presence or absence of sub-nanosecond core-valence luminescence and in crystals doped with Ce 3 the presence or absence of Ce luminescence having a (-)35 ns lifetime. We are developing a pulse discrimination technique based on digital signal processing (DSP) using a CAMAC based module from XIA, Inc. Discrimination between electrons (gammas) and the light charged particles is based on the ratio of signal amplitude in the first 50 ns to signal amplitude at a longer time interval. We are evaluating more complicated algorithms to determine whether discrimination between hydrogen isotopes and alpha particles can be achieved. These techniques may allow determination of pulse height spectra for thermal neutron capture events, fast neutron capture events, fast-neutron-induced nuclear reactions, alpha events from Ra impurities in the scintillator, and gamma events simultaneously using a single scintillator. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Aalseth, CE (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 501 EP 505 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800111 ER PT S AU Coluccia, MR Appel, JA Chiodini, G Christian, DC Kwan, S AF Coluccia, MR Appel, JA Chiodini, G Christian, DC Kwan, S BE Seibert, JA TI Characterization of prototype BTeV silicon pixel sensors before and after irradiation SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE Nuclear Science Symposium Conference Record LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID DETECTORS AB We report on measurements performed on silicon pixel sensor prototypes exposed to a 200 MeV proton beam at the Indiana University Cyclotron Facility. The sensors are of n(+)/n/p(+) type with multi-guard ring structures and p-stop electrode isolation. Electrical characterization of such devices was performed before and after irradiation up to proton fluence of 4 x 10(14) P cm(-2). We tested pixel sensors fabricated from normal and oxygen-enriched silicon wafers and with two different p-stop isolation layouts: common p-stop and individual P-stop. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 578 EP 583 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800127 ER PT S AU Mandelli, E Blanquart, L Denes, P Einsweiler, K Marchesini, R Meddeler, G Ackers, M Fisher, P Comes, G Peric, I AF Mandelli, E Blanquart, L Denes, P Einsweiler, K Marchesini, R Meddeler, G Ackers, M Fisher, P Comes, G Peric, I BE Seibert, JA TI Digital column readout architecture for the ATLAS pixel 0.25 mu m front end IC SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE Nuclear Science Symposium Conference Record LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB A fast, low noise, limited power, radiation-hard front-end chip was developed for reading out the Atlas Pixel Silicon Detector. As in the past prototypes, every chip is used to digitize and read out charge and time information from hits on each one of its 2880 inputs. The basic column readout architecture idea was adopted and modified in order to allow a safe transition to quarter micron technology and overcome any possible situation where single point defects and charge deposited by heavy ions in the silicon could have lead to unpredicted forbidden states. Moreover, the smaller feature sizes and the higher speed of these processes allowed us to enhance the design of the basic blocks and adopt a fail safe, design for testability approach. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM emandelli@lbl.gov NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 600 EP 603 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800131 ER PT S AU Popov, V Majewski, S Wojtsekhowski, B Guerin, D AF Popov, V Majewski, S Wojtsekhowski, B Guerin, D BE Seibert, JA TI A simple method to increase effective PMT gain by amplifier circuit powered from voltage divider SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB A novel concept is introduced of additional effective signal amplification by employing a dedicated circuit to process anode or dynode signal prior to sending it through a standard 50 Ohm line/cable. The circuit is entirely powered by the current flowing through the base voltage divider. Additional gain factors of 2-10 were easily achieved with preserved operation speed and rate capability up to several MHz. This additional signal boost can be used in many applications where higher gain and/or lower PMT operational voltages are desirable. For example, in the case of PMT employed in a low input light signal (such as Cherenkov counter) this technique will permit operation at a lower voltage and, therefore, will result in better operational PMT stability and longer PMT lifetime. Presently two experimental setups at Jefferson Lab are using PMT bases using this concept. C1 Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA 23606 USA. RP Popov, V (reprint author), Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA 23606 USA. NR 1 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 634 EP 637 DI 10.1109/NSSMIC.2001.1009642 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800138 ER PT S AU Anghinolfi, F Bialas, W Busek, N Ciocio, A Cosgrove, D Fadeyev, V Flacco, C Gilchriese, M Grillo, AA Haber, C Kaplon, J Lacasta, C Murray, W Niggli, H Pritchard, T Rosenbaum, F Spieler, H Stezelberger, T Vu, C Wilder, M Yaver, H Zetti, F AF Anghinolfi, F Bialas, W Busek, N Ciocio, A Cosgrove, D Fadeyev, V Flacco, C Gilchriese, M Grillo, AA Haber, C Kaplon, J Lacasta, C Murray, W Niggli, H Pritchard, T Rosenbaum, F Spieler, H Stezelberger, T Vu, C Wilder, M Yaver, H Zetti, F BE Seibert, JA TI ASIC wafer test system for the ATLAS Semiconductor Tracker front-end chip SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB An ASIC wafer test system has been developed to provide comprehensive production screening of the ATLAS Semiconductor Tracker front-end chip (ABCD3T). The ABCD3T[l] features a 128-channel analog front-end, a digital pipeline, and communication circuitry, clocked at 40 MHz, which is the bunch crossing frequency at the LHC (Large Hadron Collider). The tester measures values and tolerance ranges of all critical IC parameters, including DC parameters, electronic noise, time resolution, clock levels and clock timing. The tester is controlled by an FPGA (ORCA3T) programmed to issue the input commands to the IC and to interpret the output data. This allows the high-speed wafer-level IC testing necessary to meet the production schedule. To characterize signal amplitudes and phase margins, the tester utilizes pin-driver, delay, and DAC chips, which control the amplitudes and delays of signals sent to the IC under test. Output signals from the IC under test go through window comparator chips to measure their levels. A probe card has been designed specifically to reduce pick-up noise that can affect the measurements. The system can operate at frequencies up to 100 MHz to study the speed limits of the digital circuitry before and after radiation damage. Testing requirements and design solutions are presented. C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Anghinolfi, F (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 650 EP 654 DI 10.1109/NSSMIC.2001.1009645 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800141 ER PT S AU Beche, JF Bucher, JJ Fabris, L Riot, VJ Shuh, DK AF Beche, JF Bucher, JJ Fabris, L Riot, VJ Shuh, DK BE Seibert, JA TI High-speed nuclear quality Pulse Height Analyzer for synchrotron-based applications SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB A high throughput Pulse Height Analyzer system for synchrotron-based applications requiring high resolution, high processing speed and low dead time has been developed. The system is comprised of a 120ns 12-bit nuclear quality Analog to Digital Converter with a self-adaptive fast peak detector-stretcher and a custom-made fast histogramming memory module that records and processes the digitized data. The histogramming module is packaged in a VME/VXI compatible interface. Data is transferred through a fast optical link from the memory interface to a computer. A dedicated data acquisition program matches the hardware characteristics of the histogramming memory module. The data acquisition system allows for different data collection modes. The system can acquire data in synchronization with an external trigger or operate as a standard Pulse Height Analyzer. Acquisition can be performed on several channels simultaneously. A two-channel prototype has been demonstrated at the Stanford Synchrotron Radiation Laboratory accelerator in conjunction with a fluorescence X-ray Absorption Fine Structure Spectroscopy experiment. A detailed description of the entire system is given and experimental data shown. C1 EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Beche, JF (reprint author), EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Fabris, Lorenzo/E-4653-2013 OI Fabris, Lorenzo/0000-0001-5605-5615 NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 689 EP 692 DI 10.1109/NSSMIC.2001.1009653 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800149 ER PT S AU Spencer, DF Aryaeinejad, R Reber, EL AF Spencer, DF Aryaeinejad, R Reber, EL BE Seibert, JA TI Using the Cockroft-Walton Voltage Multiplier design in handheld devices SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB A variation of the basic Cockroft-Walton (C-W) Voltage Multiplier circuit design may be used to generate multiple voltages at sufficient currents to drive the dynodes of a photomultiplier tube. In a battery-operated handheld device, the current draw on the batteries must be kept to a minimum. Several other parameters must be considered carefully during the design as well. Components must be chosen based on size restrictions, expected load current, expected output voltage range, and the maximum allowable ripple in the output voltage. A prototype surface mount C-W board was designed and tested to power two photomultipliers. The whole system, including the detectors, draws less than 15mA of supply current with the outputs at 1000VDC. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Spencer, DF (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 746 EP 749 DI 10.1109/NSSMIC.2001.1009666 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800162 ER PT S AU Ziock, KP Madden, N Hull, E Craig, W Lavietes, T Cork, C AF Ziock, KP Madden, N Hull, E Craig, W Lavietes, T Cork, C BE Seibert, JA TI A germanium-based, coded aperture imager SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID ARRAYS AB We describe a coded-aperture based, gamma-ray imager that uses a unique hybrid germanium detector system. A planar, germanium strip detector, 11 mm thick is followed by a coaxial detector. The 19 x 19 strip detector (2 turn pitch) is used to determine the location and energy of low energy events. The location of high energy events are determined from the location of the Compton scatter in the planar detector and the energy is determined from the sum of the coaxial and planar energies. With this geometry, we obtain useful quantum efficiency in a position-sensitive mode out to 500 keV. The detector is used with a 19 x 17 URA coded aperture to obtain spectrally resolved images in the gamma-ray band. We discuss the performance of the planar detector, the hybrid system and present images taken of laboratory sources. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ziock, KP (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 9 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 864 EP 868 DI 10.1109/NSSMIC.2001.1009692 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800188 ER PT S AU Yarritu, A Spanier, S Va'vra, J AF Yarritu, A Spanier, S Va'vra, J BE Seibert, JA TI Photon background in DIRC fused silica bars SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB The DIRC (acronym for Detection of Internally Reflected Cherenkov radiation) is the ring imaging Cherenkov detector of the BABAR detector at the Pep-II ring of SLAC. The Cherenkov radiators consist of 4.9 m long rectangular fused silica bars each glued together from four equal pieces. The photon detector is a water tank equipped with an array of 10,752 conventional photomultipliers. The current study attempts to identify sources of photonic background generated in the DIRC bars. A conclusion of this work is that there are two major sources: one such component consists of photons created by the delta-ray electrons in the fused silica, which in turn can produce Cherenkov light. The second component comes from the reflections of photons from the EPOTEK-301-2 glue-fused silica interface while they are traveling in the bars. The reflection occurs because of a slight mismatch of the refraction indices. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Yarritu, A (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 892 EP 896 DI 10.1109/NSSMIC.2001.1009699 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800195 ER PT S AU Chen, W De Geronimo, G Li, Z O'Connor, P Radeka, V Rehak, P Smith, GC Yu, B AF Chen, W De Geronimo, G Li, Z O'Connor, P Radeka, V Rehak, P Smith, GC Yu, B BE Seibert, JA TI Active Pixel Sensors on high resistivity silicon and their readout SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID AMORPHOUS-SILICON; DETECTORS AB The concept of X-ray Active Matrix Pixel Sensor (XAMPS) is introduced. XAMPSs are direct illumination, position sensitive X-ray detectors with about one million pixels. They count the number of diffracted X-rays in each pixel by measuring the total charge released by converted X-rays in the body of the sensor. Readout is accomplished with a relatively small number of channels equal to the square root of the number of pixels. The estimated readout time is about 1 ms. Noise of the readout electronics can be so low that practically no additional fluctuations in the number of incident X-rays per pixel are added and therefore the XAMPS performance is very close to that of an ideal detector for X-ray crystallography. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Chen, W (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 11 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 980 EP 985 DI 10.1109/NSSMIC.2001.1009718 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800214 ER PT S AU Erickson, SA AF Erickson, SA BE Seibert, JA TI Detector requirements to curb nuclear smuggling SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB The problem of stopping nuclear smuggling of terrorist nuclear devices is a complex one, owing to the variety of pathways by which such a device can be transported. To fashion new detection systems that improve the chances of detecting such a device, it is important to know the various requirements and conditions that would be imposed on them by both the types of devices that might be smuggled and by the requirement that it not overly interfere with the transportation of legitimate goods. Requirements vary greatly from low-volume border crossings to high-volume industrial container ports, and the design of systems for them is likely to be quite different. There is also a further need to detect these devices if they are brought into a country via illicit routes, i.e., those which do not pass through customs posts, but travel overland though open space or to a smaller, unguarded airport or seaport. This paper describes some generic uses of detectors, how they need to be integrated into customs or other law enforcement systems, and what the specifications for such detectors might be. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Erickson, SA (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1028 EP 1031 DI 10.1109/NSSMIC.2001.1009728 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800224 ER PT S AU Qi, JY Kuo, CC Huesman, RH Klein, GJ Moses, WW Reutter, BW AF Qi, JY Kuo, CC Huesman, RH Klein, GJ Moses, WW Reutter, BW BE Seibert, JA TI Comparison of rectangular and dual-planar positron emission mammography scanners SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID MAP RECONSTRUCTION; BREAST-CANCER; PET; OBSERVERS AB Breast imaging using dedicated positron emission tomography (PEM) has gained much interest in the medical imaging field. In this paper, we compare the performance between rectangular PEM and parallel dual-planar PEM. Both designs are studied with DOI detectors (detectors capable of measuring the depth of interaction) and non-DOI detectors. We compare the Fisher information matrix, lesion detectability using a prewhitening observer, and quantitation of the four systems. Results show that the rectangular system with DOI has the highest signal-to-noise ratio for lesion detection and the lowest bias for quantitation for any given noise level. It also shows that for small lesions the parallel dual-planar system with DOI detectors outperforms the rectangular system with non-DOI detectors, while the rectangular system with non-DOI detectors can outperform parallel dual-planar system with DOI detectors for large lesions. This indicates that a high detector resolution is essential for small lesions, while complete sampling may be more important for large lesions. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. RP Qi, JY (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. RI Qi, Jinyi/A-1768-2010 OI Qi, Jinyi/0000-0002-5428-0322 NR 10 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1246 EP 1250 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800270 ER PT S AU Schueller, MJ Mulnix, TL Christian, BT Jensen, M Holm, S Oakes, TR Roberts, AD Dick, DW Martin, CC Nickles, RJ AF Schueller, MJ Mulnix, TL Christian, BT Jensen, M Holm, S Oakes, TR Roberts, AD Dick, DW Martin, CC Nickles, RJ BE Seibert, JA TI Addressing the third gamma problem in PET SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB PET brings the promise of quantitative imaging of the in-vivo distribution of any positron emitting nuclide, a list with hundreds of candidates. All but a few of these, the "pure positron" emitters, have isotropic, coincident gamma rays that give rise to misrepresented events in the sinogram and in the resulting reconstructed image. Of particular interest are C-10, O-14, K-38, Mn-52m Cu-60, Cu-61, Tc-94m, and I-124, each having high-energy gammas that are Compton-scattered down into the 511 keV window. The problems arising from the "third gamma," and its accommodation by standard scatter correction algorithms, were studied empirically, employing three scanner models (CTI 933/04, CTI HR+, and GE Advance), imaging three phantoms (line source, NEMA scatter, and contrast/detail), with F-18 or K-38 and As-72 mimicking O-14 and C-10, respectively, in 2D and 3D modes. Five findings emerge directly from the image analysis. The third gamma: (1) does, obviously, tax the single event rate of the PET scanners, particularly in the absence of septa, from activity outside of the axial field of view; (2) does, therefore, tax the random rate, which is second order in singles, although the gamma is a prompt coincidence partner; (3) does enter the sinogram as an additional flat background, like randoms, but unlike scatter; (4) is not seriously misrepresented by the scatter algorithm which fits the correction to the wings of the sinogram and (5) does introduce additional statistical noise from the subsequent subtraction, but does not seriously compromise the detectability of lesions as seen in the contrast/detail phantom. As a safeguard against the loss of accuracy in image quantitation, fiducial sources of known activity are included in the field of view alongside of the subject. With this precaution, a much wider selection of imaging agents can enjoy the advantages of positron emission tomography. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Schueller, MJ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Jensen, Mikael/I-8358-2012 OI Jensen, Mikael/0000-0002-9109-2187 NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1286 EP 1289 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800279 ER PT S AU Reutter, BW Gullberg, GT AF Reutter, BW Gullberg, GT BE Seibert, JA TI Effects of temporal modeling on the statistical uncertainty of spatiotemporal distributions estimated directly from dynamic SPECT projections SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE Nuclear Science Symposium Conference Record LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID RECONSTRUCTION; TOMOGRAPHY; PERFORMANCE AB Artifacts can result when reconstructing a dynamic image sequence from inconsistent single photon emission computed tomography (SPECT) projection data acquired by a slowly rotating gantry. The artifacts can lead to biases in kinetic parameters estimated from time-activity curves generated by overlaying volumes of interest on the images. To overcome these biases in conventional image based dynamic data analysis, we have been investigating the estimation of time-activity curves and kinetic model parameters directly from dynamic SPECT projection data by modeling the spatial and temporal distribution of the radiopharmaceutical throughout the projected field of view. In the present work, we perform Monte Carlo simulations to study the effects of the temporal modeling on the statistical variability of the reconstructed spatiotemporal distributions. The simulations utilize computationally efficient methods for fully four-dimensional (4-D) direct estimation of spatiotemporal distributions and their statistical uncertainties, using a spatial segmentation and temporal B-splines. The simulation results suggest that there is benefit in modeling higher orders of temporal spline continuity. In addition, the accuracy of the time modeling can be increased substantially without unduly increasing the statistical uncertainty, by using relatively fine initial time sampling to capture rapidly changing activity distributions. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1341 EP 1345 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800292 ER PT S AU Bergmann, U Ivanovic, M Glatzel, P Cramer, SP AF Bergmann, U Ivanovic, M Glatzel, P Cramer, SP BE Seibert, JA TI High-resolution x-ray imaging using rowland-circle Bragg optics SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID SPECT AB A new approach to high-resolution imaging of radio-labeled agents based on Rowland circle x-ray optics is presented. Perfect-crystal Bragg optics is widely used in x-ray research due to its high reflectivity and excellent energy resolution. The nature of Bragg reflections directly correlates energy and spatial resolution, therefore yielding good imaging properties. Applied in a one to one focusing Rowland geometry, an array of spherically bent Bragg crystals can provide a large solid angle acceptance required for efficient imaging. The potential advantage over e.g. SPECT is twofold. First, focusing optics provides a 'virtual' pinhole' which can effectively be inside the object under investigation and does not suffer from edge effects and scattering. Second, Bragg optics has an energy resolution of a few eV and discriminates against inelastic Compton scattering, a common source for image blurring. Studies using Fe-55 and (95)mTc phantoms are presented, where a spatial resolution of less than 1 mm and 2 mm was achieved respectively. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Bergmann, U (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Glatzel, Pieter/E-9958-2010 OI Glatzel, Pieter/0000-0001-6532-8144 NR 12 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1481 EP 1483 PG 3 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800323 ER PT S AU Weisenberger, AG Majewski, S Popov, V Wojcik, R AF Weisenberger, AG Majewski, S Popov, V Wojcik, R BE Seibert, JA TI High resolution detector modules based on NaI(Tl) arrays for small animal imaging SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE Nuclear Science Symposium Conference Record LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID GAMMA-CAMERA AB We are developing high spatial resolution detector modules based on recently available NaI(Tl) crystal scintillator arrays that are capable of detecting photons over a range of energies. We report on the testing of an array with individual elemet sizes of 1mm x 1mm arrays over the energy range of 28 keV to 511 keV. It is anticipated that these detector modules could be applied to small animal imaging utilizing single photon emitters such as iodine-125 (28-35 keV) and technetium-99m (140 keV); and also positron emitters such as fluorine-18. The performance of a 5cm square array o NaI(Tl) crystal scintillators in which each element is 1mm 1mm x 5mm in dimension was measured. The NaI(Tl) array manufactured by Saint-Gobain was coupled to Hamamatsu position sensitive photomultiplier tubes and tested over a range of photon energies. In particular, we tested the NaI(Tl) array with the Hamamatsu model R2487 position sensitive photomultilier tube and the new Hamamatsu model 8500 flat panel position sensitive photomultiplier tube. Though the NaI(Tl) module performed best for the single photon emitters its use in positron emission tomography applications for small animal imaging could be possible even though resulting sensitivity is not ideal. C1 Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA USA. RP Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA USA. EM drew@jlab.org; majewski@jlab.org; vpopov@jlab.org; wojcik@jlab.org NR 8 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1540 EP 1544 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800336 ER PT S AU Vaska, P Schlyer, DJ Woody, CL Stoll, SP Radeka, V Volkow, N AF Vaska, P Schlyer, DJ Woody, CL Stoll, SP Radeka, V Volkow, N BE Seibert, JA TI Imaging the unanesthetized rat brain with PET: A feasibility study SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID MICROPET; SCANNER AB The current requirement of anesthesia in PET imaging of animals has undesirable effects on the study of neurological systems and limits the types of studies that can be performed. To enable functional studies of the unanesthetized rat brain, the feasibility of a miniaturized PET tomograph that is secured directly to the head of the rat while allowing collective motion of the head and scanner, has been investigated. The proposed geometry is a septa-less, 4 cm-diameter ring tomograph with an axial extent of 2 em, that fits between the eyes and ears of a typical laboratory rat, positioning nearly the entire brain within the field of view. This geometry allows a normal posture and can be affixed with techniques currently used to secure microdialysis probes in the rat brain. The proposed detectors are state-of-the-art, but commercially available arrays of 2x2x10 mm(3) LSO crystals and matching avalanche photodiode arrays. A realistic mockup of the scanner weighing 125 g was tested on a rat and tolerated well. Studies have been carried out to estimate the performance characteristics of the proposed scanner, which are compared to those of the rodent microPET systems (UCLA prototype and commercial Concorde scanners). The parallax contribution to the spatial resolution at the edge of the brain can be reduced to microPET levels by using 2 layers of 5 mm-long crystals. Sensitivity, deadtime/countrate capability, scatter, and randoms from activity outside the field of view are estimated to be comparable to the microPET systems as well. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Vaska, P (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1569 EP 1571 PG 3 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800342 ER PT S AU Smith, MF Majewski, S Meikle, SR Weisenberger, AG Popov, V Wojcik, RF AF Smith, MF Majewski, S Meikle, SR Weisenberger, AG Popov, V Wojcik, RF BE Seibert, JA TI Design of high sensitivity, high resolution compact single photon imaging devices for small animal and dedicated breast imaging SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID ULTRA-HIGH-RESOLUTION; PINHOLE SPECT; SCINTIMAMMOGRAPHY; COLLIMATORS; SYSTEM AB Imaging the biodistribution of single photon emitting radiotracers in small animals and in the breast with high resolution and high sensitivity is an important challenge. Recent work has shown that single photon emission computed tomography (SPECT) imaging of small objects with coded aperture collimators and iterative image reconstruction may provide an order of magnitude increase in sensitivity yet maintain high spatial resolution. We propose a new system design with compact detectors for single photon small animal and breast imaging. Key features are 1) multipinhole masks for improved sensitivity, 2) pixellated NaI(TI) scintillator arrays with small crystals for high resolution and 3) flat panel or flangeless compact position sensitive photomultiplier tubes. Analyses for a small animal device with four 10 cm x 20 cm detectors and 1.5 mm detector resolution show that 0.9-1.3 mm resolution in image space could be achieved with high sensitivity for pinholes with 0.5-0.8 mm effective diameters. A design for a breast imager incorporates larger multipinhole masks, 20 cm x 20 cm pixellated detectors and lower magnification. Predicted image resolution in the center of the field of view is 1.9 mm for 0.8 mm pinholes. Additional modeling, iterative image reconstruction tests and device component tests are desirable to optimize device specifications prior to detector construction. C1 Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA 23606 USA. RP Smith, MF (reprint author), Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA 23606 USA. RI Meikle, Steven/A-5470-2009 OI Meikle, Steven/0000-0001-7397-0364 NR 22 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1592 EP 1596 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800348 ER PT S AU Wojcik, R Majewski, S Kross, B Popov, V Weisenberger, AG AF Wojcik, R Majewski, S Kross, B Popov, V Weisenberger, AG BE Seibert, JA TI Optimized readout of small gamma cameras for high resolution single gamma and positron emission imaging SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID MULTICHANNEL PMT; BREAST; SCINTIMAMMOGRAPHY; CARCINOMA; DETECTOR; PSPMT AB Using a novel resistive readout scheme and off-the-shelf PCI ADC data acquisition cards, a compact readout and control system for mini gamma cameras based on position sensitive photomultiplier tubes (PMTs) has been developed. This economical resistive readout incorporates a special fractional subtraction technique to greatly expand the useful field of view of the PMTs to the very edges of their active area as compared to standard resistive readout methods such as charge division or Anger logic. This allows one to obtain the same quality images as those obtained with much more expensive and bulky individual wire readout data acquisition systems. The four output signals from the readout circuit can be digitized by a PCI ADC card in a computer to achieve high counting rates. Results will be shown for this readout applied to a dual modality breast biopsy system currently undergoing clinical trials and an ultra high resolution single gamma small animal imaging system for studies on mice and rats. C1 Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA USA. RP Wojcik, R (reprint author), Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA USA. NR 13 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1821 EP 1825 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800400 ER PT S AU Weisenberger, AG Wojcik, R Bradley, EL Brewer, P Majewski, S Qian, J Ranck, A Saha, MS Smith, K Smith, MF Welsh, RE AF Weisenberger, AG Wojcik, R Bradley, EL Brewer, P Majewski, S Qian, J Ranck, A Saha, MS Smith, K Smith, MF Welsh, RE BE Seibert, JA TI SPECT-CT system for small animal imaging SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE Nuclear Science Symposium Conference Record LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID GAMMA-CAMERA; EMISSION AB The Detector Group at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) and the Biology, Physics and Applied Sciences Departments at the College of William and Mary are collaborating on the development of a miniature dual modality SPECT-CT system for mouse imaging. The detector heads of the SPECT subsystem are capable of imaging the gamma- and x-ray emissions (28-35 keV) of the radioactive isotope iodine-125 (le 125). Two different sets of I-125 imaging detectors ar-configured on a gantry that has an open-barrel type design. One set of detector heads is based on the 1 inch square Hamamatsu R5900-M64 position sensitive photomultiplier tube coupled to crystal scintillator arrays. The other detector heads configured on the gantry are two 5-inch diameter Hamamatsu R3292-based compact gamma cameras. The x-ray radiographic projections will be obtained using a LIXI Inc. model LF-85-503-OS x-ray imaging system that has an active area of 5.5cm in diameter. The open-barrel shaped gantry facilitates the positioning of various mini gamma-ray imaging detectors and the x-ray system. The data acquisition and gantry control is interfaced through a Macintosh G3 workstation. SPECT reconstruction results using the R5900 based detector are presented. C1 Jefferson Lab, Detector Grp, Newport News, VA USA. RP Jefferson Lab, Detector Grp, Newport News, VA USA. EM drew@jlab.org RI Qian, Jianguo/B-3663-2010 NR 21 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1840 EP 1844 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800404 ER PT S AU Popov, V Majewski, S Weisenberger, AG Wojcik, R AF Popov, V Majewski, S Weisenberger, AG Wojcik, R BE Seibert, JA TI Analog readout system with charge division type output SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB Charge division readout provides a relatively simple electronic solution for data readout of position sensitive radiation detectors. Conventional charge division usually consists of some charge division media connected to the detector outputs to provide proportional charge division between two division chain outputs. Although offering some advantages such as simplicity and the reduction of the number of analog outputs, it reduces the detector spatial resolution and image quality, because of signal to noise reduction from the attenuation of the signal before reaching the amplifiers. An analog readout system with functionally the same output as common charge division, but without a division chain connected to the detector outputs before signal amplification was designed and evaluated. This readout system operates as a multi-channel analog signal converter which converts signals from multi-channel output position sensitive devices such as multianode PMTs or gamma cameras built of PSPMT arrays etc. to two per coordinate analog outputs with same amplitude correlation as common charge division position readout. C1 Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA 23606 USA. RP Popov, V (reprint author), Thomas Jefferson Natl Accelerator Facil, Jefferson Lab, Newport News, VA 23606 USA. NR 1 TC 0 Z9 0 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1937 EP 1940 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800425 ER PT S AU Abbott, DJ Weisenberger, A Majewski, S Kieper, D Kross, B Popov, V Wojick, R Raylman, RR AF Abbott, DJ Weisenberger, A Majewski, S Kieper, D Kross, B Popov, V Wojick, R Raylman, RR BE Seibert, JA TI A high-performance VME-based acquisition system for positron emission mammography SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID BREAST-CANCER AB A prototype for a practical and economical breast imaging system for cancer detection is currently under development at Jefferson Lab. The latest advances in bright, fast, crystal scintillators, compact position-sensitive photomultipliers (PSPMT), and high-performance digitizing and readout electronics are being used to develop a compact imager based on Positron Emission Tomography (PET). To facilitate the performance demands of the detector as well as the high number of readout channels, the data acquisition system is built around an intelligent, self-contained, VME form-factor. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA USA. RP Abbott, DJ (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 1947 EP 1951 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800427 ER PT S AU Woody, CL Stoll, SP Schyler, DJ Gerasimov, M Vaska, P Shokouhi, S Volkow, N Fowler, JS Dewey, SL AF Woody, CL Stoll, SP Schyler, DJ Gerasimov, M Vaska, P Shokouhi, S Volkow, N Fowler, JS Dewey, SL BE Seibert, JA TI A study of scintillation beta microprobes SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB Several types of scintillation microprobes have recently been developed to directly measure positron activity from radiotracers in live animals. These probes consist of either a small LSO crystal or plastic scintillator coupled to an optical fiber which is read out with a photomultiplier tube operated in a single photon counting mode. Each type of probe has certain advantages and disadvantages in its ability to detect positrons and reject background gamma rays due to their different relative conversion probabilities and light output of each scintillator. In this paper, a comparison has been made of the relative detection efficiency of these two types of probes for positrons and gamma rays, and in their ability to localize positron decays using pulse height discrimination. Results are also given on the use of the microprobe on live laboratory animals. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Woody, CL (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 2002 EP 2007 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800439 ER PT S AU Klein, GJ Sitek, A Gullberg, GT Huesman, RH AF Klein, GJ Sitek, A Gullberg, GT Huesman, RH BE Seibert, JA TI Tracking cardiac twist in gated PET imagery SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID TAGGED MR-IMAGES; MOTION; PERFUSION; HEART; SPECT AB Traditional clinical techniques for imaging heart function, like gated SPECT and PET, have shown that the motion of the left ventricle during the cardiac cycle can be described by relatively global parameters such as ejection fraction, longitudinal shortening, radial contraction and wall thickening. Despite the poor spatial and temporal resolution of these datasets, a number of techniques are now available which can accurately measure these global parameters. Recently, phase contrast and tagged MRI techniques have shown that in addition to the global components, the left ventricle also exhibits considerable local twist during the cardiac cycle. We present a validation study to investigate whether this torsion can be detected and tracked in gated cardiac PET imagery. Data were acquired with 40 msec gating intervals from six normal subjects using retrospectively gated list mode PET and tagged MRI. The MRI data were analyzed using the Findtags software package and custom software to determine the ground truth motion fields. A four-dimensional deformable motion algorithm based on optical flow was then used to estimate the motion from the PET dataset. Results indicate that though the estimation algorithm can quite accurately determine the component of motion normal to the ventricular surfaces, the torsion component is considerably more difficult to track. C1 Lawrence Berkeley Natl Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. RP Klein, GJ (reprint author), Lawrence Berkeley Natl Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. OI Sitek, Arkadiusz/0000-0002-0677-4002 NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 2040 EP 2044 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800447 ER PT S AU Qi, JY Fluesman, RH AF Qi, JY Fluesman, RH BE Seibert, JA TI Lesion detection and quantitation of Positron Emission Mammography SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID MAXIMUM-LIKELIHOOD; IMAGE QUALITY; BREAST-CANCER; RECONSTRUCTION; PET; NOISE AB A Positron Emission Mammography (PEW scanner dedicated to breast imaging is being developed at our laboratory. We have developed a fist mode likelihood reconstruction algorithm for this scanner. Here we theoretically study the lesion detection and quantitation. The lesion detectabitity is studied theoretically using computer observers. We found that for the zero-order quadratic prior, the region of interest observer can achieve the performance of the prewhitening observer with a properly selected smoothing parameter. We also study the lesion quantitation using the test statistic of the region of interest observer. The theoretical expressions for the bias, variance, and ensemble mean squared error of the quantitation are derived. Computer simulations show that the theoretical predictions are in good agreement with the Monte Carlo results for both lesion detection and quantitation. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Functional Imaging, Berkeley, CA 94720 USA. RP Qi, JY (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Functional Imaging, Berkeley, CA 94720 USA. RI Qi, Jinyi/A-1768-2010 OI Qi, Jinyi/0000-0002-5428-0322 NR 17 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 2248 EP 2252 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800492 ER PT S AU Smith, MF Majewski, S Weisenberger, AG Kieper, DA Raylman, RR Turkington, TG AF Smith, MF Majewski, S Weisenberger, AG Kieper, DA Raylman, RR Turkington, TG BE Seibert, JA TI Analysis of factors affecting positron emission mammography (PEM) image formation SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID BREAST-CANCER; FDG AB Image reconstruction for positron emission mammography (PEM) with the breast positioned between two parallel, planar detectors is usually performed by backprojection to image planes. Three important factors affecting PEM image reconstruction by backprojection are investigated: 1) image uniformity (flood) corrections, 2) image sampling (pixel size) and 3) count allocation methods. An analytic expression for uniformity correction is developed that incorporates factors for spatial-dependent detector sensitivity and geometric effects from acceptance angle limits on coincidence events. There is good agreement between experimental floods from a PEM system with a pixellated detector and numerical simulations. The analytic uniformity corrections are successfully applied to image reconstruction of compressed breast phantoms and reduce the necessity for flood scans at different image planes. Experimental and simulated compressed breast phantom studies show that lesion contrast is improved when the image pixel size is half of, rather than equal to, the detector pixel size, though this occurs at the expense of some additional image noise. In PEM reconstruction counts usually are allocated to the pixel in the image plane intersected by the line of response (LOR) between the centers of the detection pixels. An alternate count allocation method is investigated that distributes counts to image pixels in proportion to the area of the tube of response (TOR) connecting the detection pixels that they overlay in the image plane. This TOR method eliminates some image artifacts that occur with the LOR method and increases tumor signal-to-noise ratios at the expense of a slight decrease in tumor contrast. Analysis of image uniformity, image sampling and count allocation methods in PEM image reconstruction points to ways of improving image formation. Further work is required to optimize image reconstruction parameters for particular detection or quantitation tasks. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Smith, MF (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 2253 EP 2257 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800493 ER PT S AU Luke, PN Lee, JS Amman, M Yu, KM AF Luke, PN Lee, JS Amman, M Yu, KM BE Seibert, JA TI Noise reduction in CdZnTe coplanar-grid detectors SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc AB Noise measurements on CdZnTe detectors show that the main sources of detector-related noise are shot noise due to bulk leakage current and 1/f noise due to the detector surfaces. The magnitude of surface leakage current appears to have little or no effect on the detector noise. Measurements on guard-ring devices fabricated using gold-evaporated contacts show that the contacts behave as Schottky barriers, and the bulk current at typical operating voltages is likely dependent on the contact properties rather than directly on the material's bulk resistivity. This also suggests that the level of shot noise is affected by the detector contacts and not necessarily by the material's bulk resistivity. A significant reduction in the noise of coplanar-grid detectors has been obtained using a modified contact fabrication process. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Luke, PN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. OI Yu, Kin Man/0000-0003-1350-9642 NR 4 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 2272 EP 2275 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800497 ER PT S AU Fabris, L Manfredi, P AF Fabris, L Manfredi, P BE Seibert, JA TI Optimization of front-end design in imaging and spectrometry applications with room temperature semiconductor detectors SO 2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 SE IEEE NUCLEAR SCIENCE SYMPOSIUM - CONFERENCE RECORD LA English DT Proceedings Paper CT IEEE Nuclear Science Symposium CY NOV 04-10, 2001 CL SAN DIEGO, CA SP IEEE, Nucl Plasma Sci Soc ID SUBMICRON CMOS TECHNOLOGIES; LHC EXPERIMENTS; PIXEL DETECTOR; PREAMPLIFIERS; ELECTRONICS; CRYSTALLOGRAPHY; MOSFETS; SYSTEM AB This paper addresses the optimization of front-end design in position sensing, imaging and high resolution energy dispersive analysis with room temperature semiconductor detectors. The focus is on monolithic solutions able to meet the requirements of high functional densities set by multielectrode, finely segmented detectors. Front-end architectures featuring additional functions besides charge measurements, as demanded by the need of acquiring and processing multiparametric information associated with the detector signals will be discussed. Noise will be an issue of dominant importance in all the foregoing analysis. The advent of CMOS processes featuring submicron gate length and gate oxide thicknesses in the few nm region is overturning some of the classical criteria in the choice of the front-end device. The achievement of the limits in resolution requires a strict control of the noise contribution from the current amplifier which ordinarily follows the front-end element in the charge-sensitive loop. This aspect becomes more crucial in designing front-end systems with submicron processes. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Fabris, L (reprint author), Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Fabris, Lorenzo/E-4653-2013 OI Fabris, Lorenzo/0000-0001-5605-5615 NR 37 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1082-3654 BN 0-7803-7324-3 J9 IEEE NUCL SCI CONF R PY 2002 BP 2363 EP 2371 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Nuclear Science & Technology; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BV30L UT WOS:000178495800517 ER PT B AU Quinn, H AF Quinn, H BE Masiero, A Senjanovic, G Smirnov, AY Thompson, G TI B physics and CP violation SO 2001 SUMMER SCHOOL ON PARTICLE PHYSICS SE ICTP LECTURE NOTES SERIES LA English DT Proceedings Paper CT Summer School on Particle Physics CY JUN 18-JUL 06, 2001 CL TRIESTE, ITALY SP Abdus Salam Int Ctr Theoret Phys ID QCD FACTORIZATION; HEAVY-QUARK; DECAYS; NONCONSERVATION; ASYMMETRIES; MODEL; MESON; MASS AB These lectures provide a basic overview of topics related to the study of CP Violation in B decays. In the first lecture, I review the basics of discrete symmetries in field theories, the quantum mechanics of neutral but flavor-non-trivial mesons, and the classification of three types of CP violation [1]. The actual second lecture which I gave will be separately published as it is my Dirac award lecture and is focussed on the separate topic of strong CP Violation. In Lecture 2 here, I cover the Standard Model predictions for neutral B decays, and in particular discuss some channels of interest for CP Violation studies. Lecture 3 reviews the various tools and techniques used to deal with the hadronic physics effects. In Lecture 4, I briefly review the present and planned experiments that can study B decays. I cannot teach all the details of this subject in this short course, so my approach is instead to try to give students a grasp of the relevant concepts and an overview of the available tools. The level of these lectures is introductory. I will provide some references to more detailed treatments and current literature, but this is not a review article so I do not attempt to give complete references to all related literature. By now there are some excellent textbooks that cover this subject in great detail [1]. I refer students to these for more details and for more complete references to the original literature. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA. RP Quinn, H (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA. EM quinn@slac.stanford.edu NR 41 TC 2 Z9 2 U1 1 U2 1 PU INT CENTRE THEORETICAL PHYSICS PI TRIESTE PA POB 586, 34100 TRIESTE, ITALY BN 92-95003-13-6 J9 ICTP LECT NOTES PY 2002 VL 10 BP 1 EP + PG 53 WC Physics, Particles & Fields SC Physics GA BY48H UT WOS:000189346500001 ER PT B AU Liliental-Weber, Z Jasinski, J Washburn, J AF Liliental-Weber, Z Jasinski, J Washburn, J BE Breza, J Dubecky, F ZatKo, B TI Differences and similarities between structural properties of GaN grown by different growth methods SO 2002 12TH INTERNATIONAL CONFERENCE ON SEMICONDUCTING & INSULATING MATERIALS LA English DT Proceedings Paper CT 12th International Semicoducting and Insulating Materials Conference (SIMC-XII2002) CY JUN 30-JUL 05, 2002 CL SMOLENICE, SLOVAKIA SP IEE, Slovak Acad Sci, IEEE Elect Devices Soc, CMK Ltd, Engn Control Syst ID PRESSURE; NITRIDES AB In this paper, defects formed in GaN grown by different methods are reviewed. The crystal growth direction and growth rate play important roles. For bulk crystals grown under high pressure the highest growth rates are for planes perpendicular to the c-axis. Only planar defects formed on c-planes are observed in these crystals. There are no threading dislocations or nanotubes in the c-direction. However, polarity of the growth direction plays a role in the surface roughness and the distribution of planar defects. For the growth of homo-epitaxial and hetero-epitaxial layers, the growth is forced to take place in the much slower c-direction. As a result, defects related to the purity of constituents used for the growth are formed such as nanotubes and pinholes. In addition, threading dislocations and dislocations that accommodate lattice and thermal expansion mismatch are formed. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Liliental-Weber, Z (reprint author), Lawrence Berkeley Lab, 62-203, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 6 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7418-5 PY 2002 BP 70 EP 75 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA BX93E UT WOS:000186888700015 ER PT B AU Kucheyev, SO Jagadish, C Williams, JS Deenapanray, PNK Yano, M Koike, K Sasa, S Inoue, M Ogata, K AF Kucheyev, SO Jagadish, C Williams, JS Deenapanray, PNK Yano, M Koike, K Sasa, S Inoue, M Ogata, K BE Breza, J Dubecky, F ZatKo, B TI Electrical isolation of ZnO by ion irradiation SO 2002 12TH INTERNATIONAL CONFERENCE ON SEMICONDUCTING & INSULATING MATERIALS LA English DT Proceedings Paper CT 12th International Semicoducting and Insulating Materials Conference (SIMC-XII2002) CY JUN 30-JUL 05, 2002 CL SMOLENICE, SLOVAKIA SP IEE, Slovak Acad Sci, IEEE Elect Devices Soc, CMK Ltd, Engn Control Syst ID DAMAGE; GAN AB We demonstrate the formation of highly resistive single-crystal ZnO epilayers as a result of irradiation with MeV Li, O, and Si ions. Results show that the ion doses necessary for electrical isolation close-to-inversely depend oil the number of ion-beam-generated atomic displacements. However, in all the cases studied, defect-induced electrical isolation of ZnO is unstable to rapid thermal annealing at temperatures above about 300degreesC No significant improvement of thermal stability is found by varying ion mass, dose, and irradiation temperature (up to 350degreesC). Finally, a comparison of implant isolation in ZnO with that in GaN is presented. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kucheyev, SO (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7418-5 PY 2002 BP 143 EP 146 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA BX93E UT WOS:000186888700030 ER PT B AU Chang, SL Zhou, CQ AF Chang, SL Zhou, CQ BE Pierson, E Jackson, WD TI Impacts of radiation heat transfer on NOx calculation furnaces SO 2002 37TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE (IECEC) LA English DT Proceedings Paper CT 37th Intersociety Energy Conversion Engineering Conference (IECEC) CY JUL 29-31, 2002 CL Washington, DC SP IEEE, AIAA, ASME, ANS, AIChe, SAE AB A computational glass furnace model was developed for the glass industry to evaluate the glass furnace performance. GFM simulates the major flow and heat transfer characteristics in both the combustion space and glass melter of the furnace, including fluid mixing, combustion, soot/NOx formation and transport, radiation heat transfer, batch melting, and glass flow. A computational fluid dynamics code is used to simulate the combustion space flow including NOx formation and transport, and spectral radiation heat transfer from soot, gaseous species, and walls. Major features of the model include the time-integral lumped oxy-fuel combustion model and direct integral solution of spectral radiation transport equation. The furnace model has been validated with experimental data from commercial glass furnaces. Radiation heat transfer in a furnace includes three major components: emission from soot and gaseous species, absorption of these species, and emission/reflection of the surrounding walls. The results of a parametric sensitivity study show that the radiation heat transfer components have significant impacts on the calculation of the gas temperature and NOx. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Chang, SL (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7296-4 PY 2002 BP 485 EP 490 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA BBC67 UT WOS:000224865700107 ER PT B AU Moreno, J Rawlinson, S Andraka, C Cordeiro, P Mehos, M Bohn, M Corey, J AF Moreno, J Rawlinson, S Andraka, C Cordeiro, P Mehos, M Bohn, M Corey, J BE Pierson, E Jackson, WD TI Dish/Stirling hybrid-heat-pipe-receiver design and test results SO 2002 37TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE (IECEC) LA English DT Proceedings Paper CT 37th Intersociety Energy Conversion Engineering Conference (IECEC) CY JUL 29-31, 2002 CL Washington, DC SP IEEE, AIAA, ASME, ANS, AIChe, SAE AB A 75-kW(t) hybrid receiver, intended for dish/Stirling application, has been designed, fabricated, and tested. The receiver is a 6-x scale-up of our earlier successful bench-scale hybrid concept. It is a major extension of the bench-scale concept to a compact package comprising a fully integrated solar absorber, gas-fired surface, heat pipe, combustor, and recuperator. The device is built around a sodium heat pipe having a spherical-dome solar absorber and a pin-fin-studded, cylindrical-sidewall, gas-fired surface. The combustion system uses a metal-matrix burner, with pre-mixed air and natural gas. The recuperator is a folded-membrane design. The receiver is designed for simultaneous solar and gas-fired heating, with a nominal throughput of 75 kW(t). The nominal operating (sodium vapor) temperature is 750C. The receiver has been ground tested (gas only) at throughput power levels from 18 to 75 kW(t) and output temperatures up to 750C. It was tested in four different orientations, corresponding to sun elevations of 12, 22, 45 and 80 degrees. The tests have established several landmarks at the 75 kW(t) power level, including: (1) preheat of fuel/air mixtures above 600C without pre-ignition, (2) internal wall temperatures over 800C with minimal warping, particularly at critical internal seals, and (3) 68% thermal efficiency including parasitics. We believe the efficiency could be boosted to 75% by the addition of an external insulation package. Our tests also verified smooth ignition, as well as the absence thermocouples, differential pressure gauges on all major flow elements, and calorimetry. Some non-fatal problems occurred during the tests, including occasional transient leakage at an internal seal, and warping of the burner matrix. Late in the scheduled tests, a hot spot developed on the heat-pipe gas-fired surface. This behavior is believed to be the result of a wick flaw; it has been seen in other heat pipes, and has been the subject of an ongoing separate effort. Design details and rationale will be presented, along with test data illustrating the behavior of the receiver, and demonstrating its efficiency. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Moreno, J (reprint author), Sandia Natl Labs, POB 5800 Ms 0703, Albuquerque, NM 87185 USA. NR 16 TC 0 Z9 0 U1 0 U2 5 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7296-4 PY 2002 BP 556 EP 564 PG 9 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA BBC67 UT WOS:000224865700118 ER PT B AU Joslyn, C Helton, JC AF Joslyn, C Helton, JC BE Keller, J Nasraoui, O TI Bounds on belief and plausibility of functionally propagated random sets SO 2002 ANNUAL MEETING OF THE NORTH AMERICAN FUZZY INFORMATION PROCESSING SOCIETY PROCEEDINGS LA English DT Proceedings Paper CT Annual Meeting of the North-American-Fuzzy-Information-Processing-Society CY JUN 27-29, 2002 CL TULANE UNIV, NEW ORLEANS, LA SP N Amer Fuzzy Informat Proc Soc, IEEE Syst, Man & Cybernet Soc HO TULANE UNIV DE random sets; Dempster-Shafer theory; Monte Carlo sampling ID FUZZY RANDOM-VARIABLES; FINITE POPULATIONS; EXPECTED VALUE AB We are interested in improving risk and reliability analysis of complex systems where our knowledge of system performance is provided by large simulation codes, and where moreover input parameters are known only imprecisely. Such imprecision lends itself to interval representations of parameter values, and thence to quantifying our uncertinay through Dempster-Shafer or Probability Bounds representations on the input space. In this context, the simulation code acts as a large "black box" function f, transforming one input Dempster-Shafer structure on the line (also known as a random interval A) into an output random interval f(A). Our quantification of output uncertainty is then based on this output random interval. If some properties of f (perhaps monotonicity or other analytical properties) are known, then some information about f(A) can be determined. But when f is a pure black box, we must resort to sampling approaches. In this paper, we present the basic formalism of a Monte Carlo approach to sampling a functionally propagated general random set, as opposed to a random interval. We show that the results of straightforward formal definitions are mathematically coherent, in the sense that bounding and convergence properties are achieved. C1 Los Alamos Natl Lab, Distributed Knowledge Syst & Modeling Team, Modeling Algorithms & Informat Grp CCS3, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Distributed Knowledge Syst & Modeling Team, Modeling Algorithms & Informat Grp CCS3, Mail Stop B265, Los Alamos, NM 87545 USA. EM joslyn@lanl.gov; jchelto@sandia.gov NR 23 TC 7 Z9 9 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7461-4 PY 2002 BP 412 EP 417 DI 10.1109/NAFIPS.2002.1018095 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA BU82T UT WOS:000177134800074 ER PT B AU Pace, MO Sauers, I James, DR Ellis, AR AF Pace, MO Sauers, I James, DR Ellis, AR GP IEEE IEEE IEEE TI Aging of lapped tape insulated model cables at cryogenic temperature SO 2002 ANNUAL REPORT CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA LA English DT Proceedings Paper CT Annual Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) CY OCT 20-24, 2002 CL CANCUN, MEXICO SP IEEE Dielectr & Electr Insulat Soc AB High temperature superconducting (HTS) power cables are generally divided into two generic designs, cold dielectric and warm dielectric. In the cold dielectric design lapped tape insulation and liquid nitrogen are used in combination to provide the electrical insulation between the conductor and the ground shield of a HTS cable. Using non HTS conductors, lapped tape insulated model cables have been tested at high voltage, including AC breakdown, negative impulse breakdown, and long term aging under AC stress. Two high voltage cryostats have been built for short and long term aging studies that permit testing model cables under the combined conditions of high electric stress, cryogenic temperature and elevated pressures up to 15 bar. A log-log plot of electric stress versus time-to-breakdown has yielded a linear curve having an "n" value indicative of cable life performance. For data obtained thus far, aging experiments (ranging from a few minutes in duration to several weeks) have yielded an n value of 26.2. Since aging at cryogenic temperatures is not expected to have a thermal cause, dielectric wear in HTS cables reduces to partial discharge as the primary cause. Phase and amplitude resolved partial discharge data of model cable in liquid nitrogen will also be presented. C1 Oak Ridge Natl Lab, High Voltage & Dielect Appl Superconduct Grp, Oak Ridge, TN 37831 USA. RP Pace, MO (reprint author), Oak Ridge Natl Lab, High Voltage & Dielect Appl Superconduct Grp, Oak Ridge, TN 37831 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7502-5 PY 2002 BP 27 EP 30 PG 4 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BV54Y UT WOS:000179333500004 ER PT B AU James, DR Sauers, I Pace, MO Ellis, AR AF James, DR Sauers, I Pace, MO Ellis, AR GP IEEE IEEE IEEE TI High voltage breakdown of solid epoxies at room temperature and in liquid nitrogen SO 2002 ANNUAL REPORT CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA LA English DT Proceedings Paper CT Annual Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) CY OCT 20-24, 2002 CL CANCUN, MEXICO SP IEEE Dielectr & Electr Insulat Soc ID INSULATION; POLYMERS AB With the development of high temperature superconductors (HTS) in flexible tape form, work has rapidly moved toward high voltage power applications such as HTS power cables, transformers, and fault current limiters. Generic to the design of these devices is the use of solid dielectric material that can hold off high voltages in combination with either vacuum or liquid nitrogen. Several types of epoxies have been screened by subjecting them to "dunk" tests in liquid nitrogen to determine which materials would not crack after immersion. Materials that survived the dunk tests were further tested for dielectric strength at room temperature and at 77 K. Stycast(R) 2850 FT/24 LV catalyst was found to decrease slightly in strength at 77 K while the Araldite(R) CY 5808/HY 5808 hardener and Stycast(R)2850 KT/11 catalyst significantly increased. These materials are found to follow a Weibull distribution. C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. RP James, DR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7502-5 PY 2002 BP 542 EP 545 PG 4 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BV54Y UT WOS:000179333500129 ER PT B AU Lehr, JM Corley, JP Elizondo, JE Corcoran, P Johnson, DL Maenchen, JM Mazarakis, M McDaniel, DH Smith, ID Kincy, M Kitterman, DL Wakefield, P Struve, K AF Lehr, JM Corley, JP Elizondo, JE Corcoran, P Johnson, DL Maenchen, JM Mazarakis, M McDaniel, DH Smith, ID Kincy, M Kitterman, DL Wakefield, P Struve, K GP IEEE IEEE IEEE TI Multi-megavolt switching in water: Considerations for the Z-R machine SO 2002 ANNUAL REPORT CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA LA English DT Proceedings Paper CT Annual Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) CY OCT 20-24, 2002 CL CANCUN, MEXICO SP IEEE Dielectr & Electr Insulat Soc AB Sandia's Z machine used water as both an insulator in power storage components as well as a switching media. The anomalously high energy density, coupled with its high dielectric strength, allow f(1)or a significant reduction in size over a gas insulated design. Moreover, the high currents required to produce ICF demand a low inductance design, which is aided by the high electrical breakdown strength of water. The inductance introduced by the spark channel is a significant source of inductance. The new design will also increase the charge voltage on the water switches and introduces serious concerns regarding the physics of electrical breakdown in water in general and the scaling of water switches in particular. A major concern is the losses associated with water switching in the multi-megavolt regime. In such large pulsed power machines, accurate estimations of switch losses are necessary for new high efficiency pulsed power the switch losses constitute a major portion of the total energy loss. Previous underestimating of energy losses have caused over predicting the accelerator outputs. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lehr, JM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7502-5 PY 2002 BP 554 EP 557 PG 4 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BV54Y UT WOS:000179333500132 ER PT B AU Sauers, I James, DR Pace, MO Ellis, AR AF Sauers, I James, DR Pace, MO Ellis, AR GP IEEE IEEE IEEE TI Surface flashover of fiberglass reinforced plastic in vacuum at cryogenic temperature SO 2002 ANNUAL REPORT CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA LA English DT Proceedings Paper CT Annual Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) CY OCT 20-24, 2002 CL CANCUN, MEXICO SP IEEE Dielectr & Electr Insulat Soc AB We have examined two fiberglass reinforced plastic (FRP) materials G-10 and G-11 in vacuum at room temperature and at 90K and compared the flashover strength with breakdown of the pure vacuum gap for a parallel plane geometry as a function of gap length. The breakdown strength for the bridged vacuum gap is lowered considerably from a pure vacuum gap, where the bridged gap exhibits a cube root dependence on the gap length. Lowering the temperature of FRP has little effect on the surface flashover strength and, if anything, tends to lower the strength slightly. This may be due to electron impact desorption of condensed gases from the dielectric surface during the conditioning process. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sauers, I (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 17 TC 1 Z9 1 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7502-5 PY 2002 BP 818 EP 821 PG 4 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BV54Y UT WOS:000179333500196 ER PT B AU Esherick, P Serkland, DK Geib, KM Peake, GM Crawford, MH Alford, WJ Allerman, AA AF Esherick, P Serkland, DK Geib, KM Peake, GM Crawford, MH Alford, WJ Allerman, AA GP IEEE IEEE TI Intracavity frequency-doubled electrically-injected VECSEL SO 2002 DIGEST OF THE LEOS SUMMER TOPICAL MEETINGS LA English DT Proceedings Paper CT Summer Topical Meeting of the Lasers-and-Electro-Optics-Society CY JUL 15-17, 2002 CL MT TREMBLANT, CANADA SP IEEE Lasers & Electro Opt Soc, IEEE C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Esherick, P (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7378-2 PY 2002 BP C7 EP C8 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BV01Q UT WOS:000177603700072 ER PT S AU Geib, PL Cox, DD Tomasi, AM AF Geib, PL Cox, DD Tomasi, AM GP IEEE IEEE TI Payload state of health monitoring design for next generation satellite constellations SO 2002 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 09-16, 2002 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc, Aerosp Corp, AstroExpo com, Circle Mt Co, GEB Software Technologies, Jet Propulsion Lab, Opt Energies Technologies Inc, Profet Enterprises AB The authors have developed a Payload State of Health (PSOH) application that monitors the State of Health (SOH) of a non-homogeneous set of payloads in a satellite constellation. This application is part of a satellite ground station that processes sensor data from payloads and monitors the SOH of the ground station itself. The first payload of the constellation was launched in 2001. The PSOH application was used successfully for Early Orbit Turn-on (EOT) testing, and it is currently processing data autonomously. The PSOH application was developed with three types of users in mind. It accommodates the needs of payload designers who predominately use it during EOT. It uses a highly intuitive graphical Human Computer Interface (HCI) that allows a non-expert ground station operator to monitor all payloads of the constellation with a minimal chance of human error. It generates messages that provide a persistent record of any anomalies for use by the sensor data analyst. This paper shows how early development of the ground station PSOH application can benefit the three main users the sensor designer, the operator, and the data analyst. C1 Sandia Natl Labs, Adv Informat Architectures Dept 6532, Albuquerque, NM 87185 USA. RP Geib, PL (reprint author), Sandia Natl Labs, Adv Informat Architectures Dept 6532, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-7231-X J9 AEROSP CONF PROC PY 2002 BP 205 EP 214 PG 10 WC Engineering, Aerospace SC Engineering GA BV66P UT WOS:000179697800019 ER PT S AU Eilers, DL Esfahani, SS Leatherwood, MJ Otts, SL Perea, WL Smith, PA AF Eilers, DL Esfahani, SS Leatherwood, MJ Otts, SL Perea, WL Smith, PA GP IEEE IEEE TI Intel architecture for military and space applications SO 2002 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 09-16, 2002 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc, Aerosp Corp, AstroExpo com, Circle Mt Co, GEB Software Technologies, Jet Propulsion Lab, Opt Energies Technologies Inc, Profet Enterprises AB Sandia National Laboratories, in partnership with NASA, the National Reconnaissance Office, and the Air Force Research Laboratory, is developing a radiation-hardened emulation of the popular Pentium(R) Architecture for use in military and space applications. This interagency program addresses the critical need for high performance computing in military and space applications. Support, affordability, and risk are being,addressed by migrating commercial designs, debugged and supported by the high-volume consumer marketplace, into military and space applications. Preserving the investment that the consumer marketplace has made in supporting and debugging these chips is accomplished by creating an exact emulation of the Pentium(R) architecture. Using the Intel-supplied design source code, Sandia is creating a clock-cycle-by-clock-cycle accurate radiation-hardened implementation of the Pentium(R). The original Intel design was obtained through a licensing agreement 3 between Sandia National Laboratories and Intel Corporation. The provisions of this license agreement address the specific needs of the United States government military and space applications as well as other potential markets not served by the commercial sector. To complement the radiation-hardened implementation of the Pentium(R) microprocessor, Sandia is also creating a radiation-hardened Integrated Bridge Chip (IBC) that is based on the Intel 430HX(R) chipset. In addition to being radiation-hardened this bridge chip design is being designed specifically for embedded applications. The Radiation-Hardened Processor (RHP) and IBC designs will be fabricated on a radiation-hardened 0.35mum CMOS/SOI process at Sandia's integrated circuit foundry in Albuquerque, New Mexico. The chipset will be hardened for total dose, dose ,rate, and single event effects (SEE). Sandia's SOI technology hardness levels will enable the RHP and IBC implementations to be used in both strategic weapon and space environments. First silicon for the radiation-hardened processor and IBC is scheduled for March 2002 and June 2002, respectively. Flight quality parts will be available in March 2003. While initially these chips will be fabricated and sold by Sandia National Laboratories, the licensing agreement provides for a manufacturing database transfer to the commercial sector. Such a transfer will be considered when the demand for the chips and industry interest in manufacturing dictate. Individual microprocessor and bridge chip integrated circuits will be available for purchase by all system and sub-system developers subject only to federal export control regulations and market restrictions set forth in the Intel license agreement. This paper provides the reader with a brief introduction to the issues involved in migrating commercial technology to military and space applications. The paper starts with the basic technological need, describes the issues involved in obtaining a licensing agreement, discusses the technical designs involved, and concludes with performance specifications and availability of chips to final users. While the treatment is brief, the reader should gain a good appreciation for why migrating complex commercial designs to the military market place is a non-trivial undertaking. Government readers should also come away with an understanding of the risks involved in such a transfer as well as some of the risk mitigation approaches crafted into this particular program. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Eilers, DL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-7231-X J9 AEROSP CONF PROC PY 2002 BP 1843 EP 1854 PG 12 WC Engineering, Aerospace SC Engineering GA BV66P UT WOS:000179697800179 ER PT S AU McBrayer, JD AF McBrayer, JD GP IEEE IEEE TI An overview of Sandia National Laboratories' MEMS activities SO 2002 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 09-16, 2002 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc, Aerosp Corp, AstroExpo com, Circle Mt Co, GEB Software Technologies, Jet Propulsion Lab, Opt Energies Technologies Inc, Profet Enterprises AB Sandia National Laboratories has a substantial effort in development of microelectromechanical system (MEMS) technologies. This miniaturization capability can lead to low-cost, small, high-performance, "systems-on-achip", and have many applications ranging from advanced military space systems to large-volume commercial markets like automobiles, rf or land-based communication networks and equipment, or commercial electronics. One of the key challenges in realization of the microsystem is integration of several technologies including digital electronics; analog and rf electronics, optoelectronics, sensors, and actuators, and advanced packaging technologies. This paper will provide an overview of Sandia's MEMS activities. Microscopic devices such as gears, transmissions, pop-up mirrors (such as those planned for the next generation telescope), and shutters, fabricated using silicon surface micromachining, techniques will be presented. Various sensors and the technology details used to create them will also be described. Such devices and technologies should provide aerospace system designers with a new set of tools for creating the next generation of space hardware. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP McBrayer, JD (reprint author), Sandia Natl Labs, POB 5800,MS-1078, Albuquerque, NM 87185 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-7231-X J9 AEROSP CONF PROC PY 2002 BP 2019 EP 2024 PG 6 WC Engineering, Aerospace SC Engineering GA BV66P UT WOS:000179697800196 ER PT S AU Plyasunov, S Arkin, AP AF Plyasunov, S Arkin, AP GP IEEE IEEE TI Motifs and modules in cellular signal processing SO 2002 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, VOLS I-IV, PROCEEDINGS SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech, and Signal Processing CY MAY 13-17, 2002 CL ORLANDO, FL SP IEEE Signal Proc Soc ID DISTRIBUTIONS; CONSTRUCTION; NETWORKS; KINETICS AB Bacterial and animal cells are dynamic machines whose internal chemical networks perform hundreds of complex control and signal processing tasks to govern cellular development over time and in response to deterministic and stochastic signals from the environment. A central challenge in post-genomic biology is to discover the complete physical nature of these networks and to determine if there are principles of control and signal processing by which these cell operate and evolve. If such principles exist then they are handles by which cellular engineers can determine the best placement of external signals (such as pharmaceuticals) to cause a cell to move from an undesired state to a desired state. Here, initial attempts at determining the principles of control, the possible modular structure and the nature of signal flow in cellular networks are briefly introduced. C1 Univ Calif Berkeley, EO Lawrence Berkeley natl Lab, Phys Biosci Div, Dept Phys, Berkeley, CA 94720 USA. RP Plyasunov, S (reprint author), Univ Calif Berkeley, EO Lawrence Berkeley natl Lab, Phys Biosci Div, Dept Phys, 1 Cyclotron Rd MS 3-144, Berkeley, CA 94720 USA. RI Arkin, Adam/A-6751-2008 OI Arkin, Adam/0000-0002-4999-2931 NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-7402-9 J9 INT CONF ACOUST SPEE PY 2002 BP 4032 EP 4035 PG 2 WC Acoustics; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology SC Acoustics; Computer Science; Engineering; Imaging Science & Photographic Technology GA BU96P UT WOS:000177510401009 ER PT B AU Sottile, MJ Minnich, RG AF Sottile, MJ Minnich, RG BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Supermon: A high-speed cluster monitoring system SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp AB Supermon is a flexible set of tools for high speed, scalable cluster monitoring. Node behavior can be monitored much faster than with other commonly used methods (e.g., rstatd). In addition, Supermon uses a data protocol based on symbolic expressions (S-expressions) at all levels of Supermon, from individual nodes to entire clusters. This contributes to Supermon's scalability and allows it to function in a heterogeneous environment. This paper presents the Supermon architecture and discuss initial performance measurements on a cluster of heterogeneous Alpha-processor based nodes. C1 Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. RP Sottile, MJ (reprint author), Los Alamos Natl Lab, Adv Comp Lab, MS-B287, Los Alamos, NM 87545 USA. NR 8 TC 9 Z9 11 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 0-7695-1745-5 PY 2002 BP 39 EP 46 DI 10.1109/CLUSTR.2002.1137727 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400004 ER PT B AU Evard, R Desai, N Navarro, JP Nurmi, D AF Evard, R Desai, N Navarro, JP Nurmi, D BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Clusters as large-scale development facilities SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp AB In this paper, we describe the use of a cluster as a generalized facility for development. A development facility is a system used primarily for testing and development activities while being operated reliably for many users. We are in the midst of a project to build and operate a large-scale development facility. We discuss our motivation for using clusters in this way and compare the model with a classic computing facility. We describe our experiences and findings from the first phase of this project. Many of these observations are relevant to the design of standard clusters and to future development facilities. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Evard, R (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 6 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1745-5 PY 2002 BP 54 EP 63 DI 10.1109/CLUSTR.2002.1137729 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400006 ER PT B AU Alexeev, Y Schmidt, MW Windus, TL Gordon, MS Kendall, RA AF Alexeev, Y Schmidt, MW Windus, TL Gordon, MS Kendall, RA BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Performance and implementation of distributed data CPHF and SCF algorithms SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp ID COMPUTATIONAL CHEMISTRY AB This paper describes a novel distributed data parallel Self Consistent Field (SCF) algorithm and the distributed data Coupled Perturbed Hartree-Fock (CPHF) step of an analytic Hessian algorithm. The distinguishing features of these algorithms are: (a) columns of density and Fock matrices are distributed among processors, (b) pair-wise dynamic load balancing and an efficient static load balancer were developed to achieve a good workload, (c) network communication time is minimized via careful analysis of data flow in the SCF and CPHF algorithms. By using a shared memory model, novel work load balancers, and improved analytic Hessian steps, we have developed codes that achieve superb performance. The performance of the CPHF code is demonstrated on a large biological system. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Gordon, MS (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. EM mark@si.fi.ameslab.gov NR 16 TC 2 Z9 2 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1745-5 PY 2002 BP 135 EP 142 DI 10.1109/CLUSTR.2002.1137738 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400015 ER PT B AU Turner, D Chen, XH AF Turner, D Chen, XH BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Protocol-dependent message-passing performance on Linux clusters SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp AB In a Linux cluster, as in any multi-processor System, the inter-processor communication rate is the major limiting factor to its general usefulness. This research is geared toward improving the communication performance by identifying where the inefficiencies lie and trying to understand their cause. The NetPIPE utility is being used to compare the latency and throughput of all current message-passing libraries and the native software layers they run upon for a variety of hardware configurations. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Turner, D (reprint author), Iowa State Univ, Ames Lab, 327 Wilhelm Hall, Ames, IA 50011 USA. NR 12 TC 12 Z9 13 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 0-7695-1745-5 PY 2002 BP 187 EP 194 DI 10.1109/CLUSTR.2002.1137746 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400020 ER PT B AU Wu, MS Aluru, S Kendall, RA AF Wu, MS Aluru, S Kendall, RA BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Mixed mode matrix multiplication SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp AB In modem clustering environments where the memory hierarchy has many layers (distributed memory, shared memory layer cache,...), an important question is how to fully utilize all available resources and identify the most dominant layer in certain computation. When combining algorithms on all layers together what would be the best method to get the best performance out of all the resources we have? Mixed mode programming model that uses thread programming on the shared memory layer and message passing programming on the distributed memory, layer is a method that many researchers are using to utilize the memory resources. In this paper we take an algorithmic approach that uses matrix multiplication as a tool to show how cache algorithms affect the performance of both shared memory, and distributed memory algorithms. We show that with good underlying cache algorithm, overall performance is stable. When underlying cache algorithm is bad, superlinear speedup may occur and increasing number of threads may also improve performance. C1 US DOE, Ames Lab, Dept Elect & Comp Engn, Scalable Comp Lab, Ames, IA 50011 USA. RP Wu, MS (reprint author), US DOE, Ames Lab, Dept Elect & Comp Engn, Scalable Comp Lab, Ames, IA 50011 USA. NR 15 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 0-7695-1745-5 PY 2002 BP 195 EP 203 DI 10.1109/CLUSTR.2002.1137747 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400021 ER PT B AU Pedretti, K Brightwell, R Williams, J AF Pedretti, K Brightwell, R Williams, J BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Cplant (TM) runtime system support for multi-processor and heterogeneous compute nodes SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp DE commodity cluster; runtime system; multiprocessor; heterogeneous computing ID PERFORMANCE AB In this paper, we describe additions and modifications to the Computational Plant (Cplant(TM)) system software to support multi-processor compute nodes and to support heterogeneous node types. We describe how these capabilities have been incorporated into our scalable runtime system and how these changes affect the interface seen by end users and application developers. We also discuss several important operating system and networking issues that can directly impact application performance. We present some initial performance metrics that indicate how our current implementation scales when multiple processes are running on a single node. C1 Sandia Natl Labs, Scalable Comp Syst Dept, Albuquerque, NM 87185 USA. RP Pedretti, K (reprint author), Sandia Natl Labs, Scalable Comp Syst Dept, POB 5800, Albuquerque, NM 87185 USA. NR 14 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 0-7695-1745-5 PY 2002 BP 207 EP 214 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400022 ER PT B AU Navarro, JP Evard, R Nurmi, D Desai, N AF Navarro, JP Evard, R Nurmi, D Desai, N BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Scalable cluster administration - Chiba city I approach and lessons learned SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp AB Systems administrators of large clusters often need to perform the same administrative task hundreds or thousands of times. Administrators have traditionally performed some time-consuming tasks, such as operating system installation, configuration, and maintenance, manually. By combining network services such as DHCP, TFTP, FTP, HTTP, and NFS with remote hardware control and scripted installation, configuration, and maintenance techniques, cluster administrators can automate these administrative tasks. Scalable cluster administration addresses this challenge: What hardware and software design techniques can cluster builders use to automate cluster administration on very large clusters? We describe the approach used in the Mathematics and Computer Science Division of Argonne National Laboratory on Chiba City 1, a 314-node Linux cluster; and we analyze the scalability, flexibility, performance and reliability benefits and limitations from that approach. C1 Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. RP Navarro, JP (reprint author), Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. NR 4 TC 2 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1745-5 PY 2002 BP 215 EP 221 DI 10.1109/CLUSTR.2002.1137749 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400023 ER PT B AU Feng, W Warren, M Weigle, E AF Feng, W Warren, M Weigle, E BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI The Bladed Beowulf: A cost-effective alternative to traditional Beowulfs SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp DE Beowulf; cluster; blade server; RLX; Trans-meta; code morphing; VLIW; price-performance ratio; performance-power ratio; performance-space ratio; ToPPeR AB We present a new twist to the Beowulf cluster - the Bladed Beowulf In contrast to traditional Beowulfs which typically use Intel or AMD processors, our Bladed Beowulf uses Trans-meta processors in order to keep thermal power dissipation low and reliability and density high while still achieving comparable performance to Intel- and AMD-based clusters. Given the ever increasing complexity of traditional super-computers and Beowulf clusters; the issues of size, reliability, power consumption, and ease of administration and use will be "the" issues of this decade for high-performance computing. Bigger and faster machines are simply not good enough anymore. To illustrate, we present the results of performance benchmarks on our Bladed Beowulf and introduce two performance metrics that contribute to the total cost of ownership (TCO) of a computing system - performance/power and performance/space. C1 Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. RP Feng, W (reprint author), Los Alamos Natl Lab, Adv Comp Lab, POB 1663, Los Alamos, NM 87545 USA. EM feng@lanl.gov; msw@lanl.gov; ehw@lanl.gov NR 17 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1745-5 PY 2002 BP 245 EP 254 DI 10.1109/CLUSTR.2002.1137753 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400027 ER PT B AU Gropp, W Lusk, E AF Gropp, W Lusk, E BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Goals guiding design: PVM and MPI SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp AB PVM and MPI, two systems for programming clusters, are often compared. The comparisons usually start with the unspoken assumption that PVM and MPI represent different solutions to the same problem. In this paper we show that, in fact, the two systems often are solving different problems. In cases where the problems do match but the solutions chosen by PVM and MPI are different, we explain the reasons for the differences. Usually such differences can be traced to explicit differences in the goals of the two systems, their origins, or the relationship between their specifications and their implementations. For example, we show that the requirement for portability and performance across many platforms caused MPI to choose approaches different from those made by PVM, which is able to exploit the similarities of network-connected systems. 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; lusk@mcs.anl.gov NR 28 TC 1 Z9 2 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 0-7695-1745-5 PY 2002 BP 257 EP 265 DI 10.1109/CLUSTR.2002.1137754 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400028 ER PT B AU Laros, JH Ward, L Dauchy, NW Brightwell, R Hudson, T Klundt, R AF Laros, JH Ward, L Dauchy, NW Brightwell, R Hudson, T Klundt, R BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI An extensible, portable, scalable cluster management software architecture SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp DE cluster management; commodity clusters; cluster architecture; commercial off the shelf (COTS) AB This paper describes an object-oriented software architecture for cluster integration and management that enables extensibility, portability, and scalability. This architecture has been successfully implemented and deployed on several large-scale production clusters at Sandia National Laboratories, the largest of which is currently 1861 nodes. This paper discusses the key features of the architecture that allow for easily extending the range of supported hardware devices and network topologies. We also describe in detail how the object-oriented structure that represents the hardware components can be used to implement scalable and portable cluster management tools. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Laros, JH (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 1 TC 1 Z9 1 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1745-5 PY 2002 BP 287 EP 295 DI 10.1109/CLUSTR.2002.1137757 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400031 ER PT B AU Leung, VJ Arkin, EM Bender, MA Bunde, D Johnston, J Lal, A Mitchell, JSB Phillips, C Seiden, SS AF Leung, VJ Arkin, EM Bender, MA Bunde, D Johnston, J Lal, A Mitchell, JSB Phillips, C Seiden, SS BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI Processor allocation on Cplant: Achieving general processor locality using one-dimensional allocation strategies SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp ID DYNAMIC STORAGE-ALLOCATION; BIN PACKING; CURVES; COMPRESSION; ALGORITHMS; BOUNDS AB The Computational Plant or Cplant is a commodity-based supercomputer under development at Sandia National Laboratories. This paper describes resource-allocation strategies to achieve processor locality for parallel jobs in Cplant and other supercomputers. Users of Cplant and other Sandia supercomputers submit parallel jobs to a job queue. When a job is scheduled to run, it is assigned to a set of processors. To obtain maximum throughput, jobs should be allocated to localized clusters of processors to minimize communication costs and to avoid bandwidth contention caused by overlapping jobs. This paper introduces new allocation strategies and performance metrics based on space-filling curves and one dimensional allocation strategies. These algorithms are general and simple, Preliminary simulations and Cplant experiments indicate that both space-filling curves and one-dimensional packing improve processor locality compared to the sorted free list strategy previously used on Cplant. These new allocation strategies are implemented in the new release of the Cplant System Software, Version 2.0, phased into the Cplant systems(1) at Sandia by May 2002. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, MS 1110, Albuquerque, NM 87185 USA. EM vjleung@sandia.gov; estie@ams.sunysb.edu; bender@cs.sunysb.edu; bunde@uiuc.edu; jjohnst@sandia.gov; alal@eecs.tufts.edu; sbml@ams.sunysb.edu; caphill@sandia.gov; sseiden@acm.org NR 46 TC 28 Z9 28 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 0-7695-1745-5 PY 2002 BP 296 EP 304 DI 10.1109/CLUSTR.2002.1137758 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400032 ER PT B AU Gan, ZT Alexeev, Y Kendall, RA Gordon, MS AF Gan, ZT Alexeev, Y Kendall, RA Gordon, MS BE Gropp, B Pennington, R Reed, D Baker, M Brown, M Buyya, R TI A distributed data implementation of parallel full CI program SO 2002 IEEE INTERNATIONAL CONFERENCE ON CLUSTER COMPUTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Cluster Computing CY SEP 23-26, 2002 CL CHICAGO, IL SP IEEE Comp Soc, Task Force Cluster Comp ID CONFIGURATION-INTERACTION METHOD; ALGORITHM AB A distributed data parallel full CI program is described The implementation of the FCI algorithm is organized in a combined Cl driven approach With extra computation we were able to avoid redundant communication, and convert the collective communication into more efficient point-to-point communication. The network performance is further optimized by improved DDI library. Examples show very good speedup performance on 16 node PC clusters. The application of the code is also demonstrated. C1 US DOE, Ames Lab, Scalable Comp Lab, Ames, IA 50011 USA. RP Gan, ZT (reprint author), US DOE, Ames Lab, Scalable Comp Lab, Ames, IA 50011 USA. NR 8 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 0-7695-1745-5 PY 2002 BP 476 EP 479 DI 10.1109/CLUSTR.2002.1137786 PG 4 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV34X UT WOS:000178628400055 ER PT B AU Grimmell, WC Rao, NSV AF Grimmell, WC Rao, NSV GP IEEE IEEE TI Computing path-tables of quickest paths under different routing mechanisms SO 2002 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, VOLS 1-5, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Communications CY APR 28-MAY 02, 2002 CL NEW YORK, NY SP IEEE Commun Soc, ICC GLOBECOM, IEEE, AT&T Labs, Avaya Labs, Nippon Telegraph & Telephone, Nokia, Polytech Univ, Verizon Commun DE end-to-end delay; quickest paths; path-tables; quality of service ID ALGORITHMS AB Several recent transport methods employ routing at a level such as the datagram, TCP stream, or application level in order to address quality of service in wide-area networks. The quickest path problem deals with the transmission of a message from a source to a destination with the minimum end-to-end delay over a network with delay and bandwidth constraints on the links. The minimum end-to-end delay path depends on the routing mechanism used for transport in addition to the message size and the link bandwidths and delays. We present algorithms for computing the path-table that specifies the minimum end-to-end delay path as a function of message size for six routing modes reflecting mechanisms such as circuit switching, Internet protocol, and their combinations. These algorithms have polynomial time complexity in some cases, and in others achieve polynomial time complexity when the set of link bandwidths is suitably bounded. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Grimmell, WC (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. OI Rao, Nageswara/0000-0002-3408-5941 NR 7 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7400-2 PY 2002 BP 2318 EP 2324 PG 7 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BV10L UT WOS:000177818300446 ER PT B AU Ding, C He, XF AF Ding, C He, XF BE Kumar, V Tsumoto, S Zhong, N Yu, PS Wu, XD TI Cluster merging and splitting in hierarchical clustering algorithms SO 2002 IEEE INTERNATIONAL CONFERENCE ON DATA MINING, PROCEEDINGS LA English DT Proceedings Paper CT 2nd IEEE International Conference on Data Mining CY DEC 09-12, 2002 CL MAEBASHI CITY, JAPAN SP IEEE Comp Soc Tech Comm Pattern Anal & Machine Intelligence, IEEE Comp Soc Tech Comm Computat Intelligence, Maebashi Convent Bur, Maebashi City Govt, Gunmma Prefecture Govt, Maebashi Inst Technol, AdIn Res Inc, Japan Res Inst Ltd, Support Ctr Adv Telecommun Technol Res, US AFOSR, AOARD, AROFE, SAS Inst Japan, SPSS Japan Inc, Kankodo, Syst Alpha Inc, GCC Inc, Yamato Inc, Daiei Dream Co Ltd AB Hierarchical clustering constructs a hierarchy of clusters by either repeatedly merging two smaller clusters into a larger one or splitting a larger cluster into smaller ones. The crucial step is how to best select the next cluster(s) to split or merge. Here we provide a comprehensive analysis of selection methods and propose several new methods. We perform extensive clustering experiments to test 8 selection methods, and find that the average similarity is the best method in divisive clustering and the MinMax linkage is the best in agglomerative clustering. Cluster balance is a key factor to achieve good performance. We also introduce the concept of objective function saturation and clustering target distance to effectively assess the quality of clustering. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC Div, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC Div, Berkeley, CA 94720 USA. EM chqding@lbl.gov; xhe@lbl.gov NR 10 TC 26 Z9 29 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1754-4 PY 2002 BP 139 EP 146 DI 10.1109/ICDM.2002.1183896 PG 8 WC Computer Science, Artificial Intelligence SC Computer Science GA BV87U UT WOS:000180274000018 ER PT B AU Ding, C He, XF Zha, HY Simon, HD AF Ding, C He, XF Zha, HY Simon, HD BE Kumar, V Tsumoto, S Zhong, N Yu, PS Wu, XD TI Adaptive dimension reduction for clustering high dimensional data SO 2002 IEEE INTERNATIONAL CONFERENCE ON DATA MINING, PROCEEDINGS LA English DT Proceedings Paper CT 2nd IEEE International Conference on Data Mining CY DEC 09-12, 2002 CL MAEBASHI CITY, JAPAN SP IEEE Comp Soc Tech Comm Pattern Anal & Machine Intelligence, IEEE Comp Soc Tech Comm Computat Intelligence, Maebashi Convent Bur, Maebashi City Govt, Gunmma Prefecture Govt, Maebashi Inst Technol, AdIn Res Inc, Japan Res Inst Ltd, Support Ctr Adv Telecommun Technol Res, US AFOSR, AOARD, AROFE, SAS Inst Japan, SPSS Japan Inc, Kankodo, Syst Alpha Inc, GCC Inc, Yamato Inc, Daiei Dream Co Ltd AB It is well-known that for high dimensional data clustering, standard algorithms such as EM and the K-means are often trapped in local minimum. Many initialization methods were proposed to tackle this problem, but with only limited success. In this paper we propose a new approach to resolve this problem by repeated dimension reductions such that K-means or EM are performed only in very low dimensions. Cluster membership is utilized as a bridge between the reduced dimensional sub-space and the original space, providing flexibility and ease of implementation. Clustering analysis performed on highly overlapped Gaussians, DNA gene expression profiles and internet newsgroups demonstrate the effectiveness of the proposed algorithm. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC Div, Berkeley, CA 94720 USA. RP Ding, C (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC Div, Berkeley, CA 94720 USA. NR 29 TC 36 Z9 39 U1 0 U2 5 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1754-4 PY 2002 BP 147 EP 154 DI 10.1109/ICDM.2002.1183897 PG 8 WC Computer Science, Artificial Intelligence SC Computer Science GA BV87U UT WOS:000180274000019 ER PT B AU Dixon, WE Zergeroglu, E Fang, Y Dawson, DM AF Dixon, WE Zergeroglu, E Fang, Y Dawson, DM GP IEEE IEEE IEEE TI Object tracking by a robot manipulator: A robust cooperative visual servoing approach SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc ID HAND-EYE COORDINATION; SYSTEMS AB In this paper, we utilize a Lyapunov-based design approach to construct a visual servoing controller for a robot manipulator that ensures uniformly ultimately bounded (UUB) end-effector position tracking performance despite parametric uncertainty throughout the entire robot/camera system. The UUB end-effector tracking result exploits information from both a fixed camera and a camera-in-hand, although both cameras contain parametric uncertainty in the calibration parameters (e.g., focal length, image center, scaling factors, and camera position and orientation). The advantages of the cooperative camera configuration are that: (i) the fixed camera can be mounted so that a large robot workspace is visible, (ii) the camera-in hand is mounted so that a high resolution, close-up view of an object is achieved, facilitating the potential for more precise robotic motion. and (iii) the fixed camera provides a mechanism for treating the problem of determining the relative velocity of the robot end-effector with respect to the object for the camera-in-hand object tracking problem when the camera is uncalibrated. C1 Oak Ridge Natl Lab, Engn Sci & Technol Div Robot, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Engn Sci & Technol Div Robot, Oak Ridge, TN 37831 USA. EM dixonwe@ornl.gov; ezerger@ofsoptics.com; yfang@ces.clemson.edu; ddawson@ces.clemson.edu NR 32 TC 12 Z9 13 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 211 EP 216 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200034 ER PT B AU Madhavan, R Fregene, K Parker, LE AF Madhavan, R Fregene, K Parker, LE GP IEEE IEEE IEEE TI Distributed heterogeneous outdoor multi-robot localizationt SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc DE multi-robot localization; heterogeneous sensing; distributed state estimation; cooperative navigation AB An Extended Kalman Filter-based algorithm for the localization of a team of robots is described in this paper. The distributed EKF localization scheme is straightforward in that the individual robots maintain a pose estimate using EKFs that are local-to every robot. We then show how these results can be extended to perform heterogeneous cooperative localization in the absence or degradation of absolute sensors aboard the team members. The proposed algorithms are implemented using field data obtained from a team, of ATRV-Mini robots traversing on uneven outdoor terrain. C1 Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. RP Madhavan, R (reprint author), Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Comp Sci & Math Div, POB 2008, Oak Ridge, TN 37831 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 374 EP 381 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200060 ER PT B AU Xavier, PG AF Xavier, PG GP IEEE IEEE IEEE TI Implicit convex-hull distance of finite-screw-swept volumes SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc ID COLLISION DETECTION; POLYHEDRA; ALGORITHM; OBJECTS AB dThe need for collision detection arises in several robotics areas, including motion-planning, online collision avoidance, and simulation. At the heart of most current methods are algorithms for interference detection and/or distance computation. In [34] we presented an implemented technique for doing exact numerical distance computation and interference detection for translationally-swept bodies and approximate techniques for bodies swept under finite screw motion. Here, we extend the Enhanced GJK and Gilbert-Foo algorithms to obtain exact numerical distance computation and interference detection between the convex hulls of the volumes swept by two convex polyhedra under finite screw motions. This algorithm enables conservative distance and collision computations that are both tighter and more efficient than the previous result. It has been integrated into a bounding-volume hierarchy distance/interference code to extend the result to facetted non-convex rigid bodies. C1 Sandia Natl Labs, Intelligent Syst Principles, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Intelligent Syst Principles, POB 5800, Albuquerque, NM 87185 USA. EM pgxavie@sandia.gov NR 34 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 847 EP 854 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200134 ER PT B AU Varma, VK Dixon, WE AF Varma, VK Dixon, WE GP IEEE IEEE IEEE TI Design of a piezoelectric meso-scale mobile robot: A compliant amplification approach SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc ID ACTUATORS; MICROMETER AB In this paper, the development of a novel piezoelectric-based locomotion design for a meso-scale mobile robot is described. The design exploits a compliant mechanical structure that enables piezoelectric forces to be amplified and transmitted to "legs" that propel the robot through a lift and pull scheme. The lift and pull design contrasts with typical slip/stick approaches that assume the inertia effects of the robot will allow the robot to slip on a smooth surface. By eliminating the slipping assumption, the potential surfaces that the proposed robot can traverse is significantly extended. Discussions are provided regarding the proposed locomotion method, kinematic modeling and system constraints, mechanical optimization, and control of the meso-scale robot. C1 Oak Ridge Natl Lab, Nucl Sci & Technol Div Remote Syst, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Nucl Sci & Technol Div Remote Syst, Oak Ridge, TN 37831 USA. EM varmavk@orul.gov; dixonwe@orul.gov NR 21 TC 4 Z9 5 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 1137 EP 1142 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200179 ER PT B AU Fregene, K Madhavan, R Parker, LE AF Fregene, K Madhavan, R Parker, LE GP IEEE IEEE IEEE TI Incremental multiagent robotic mapping of outdoor terrains SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc DE multirobot mapping; terrain mapping; depth-from-motion; robot vision AB We describe a scheme for building terrain maps of realistic outdoor environments by having multiple robotic agents navigate in them. The terrain-map combines vision-based depth information of environmental features with an elevation gradient created by fusing vertical displacements obtained from inclinometer pitch angles with DGPS altitude data. Experimental results are presented to illustrate the practical application of this scheme. C1 Oak Ridge Natl Lab, Ctr Engn Sci & Adv Res, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. RP Fregene, K (reprint author), Oak Ridge Natl Lab, Ctr Engn Sci & Adv Res, Comp Sci & Math Div, POB 2008, Oak Ridge, TN 37831 USA. NR 13 TC 10 Z9 10 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 1339 EP 1346 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200211 ER PT B AU Guo, Y Parker, LE AF Guo, Y Parker, LE GP IEEE IEEE IEEE TI A distributed and optimal motion planning approach for multiple mobile robots SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc DE multi robots; motion planning; performance index; cost function; coordination diagram ID 2 ROBOTS; TIME; OBJECTS AB We propose a distributed and optimal motion planning algorithm for multiple robots. The computationally expensive problem is decomposed into two modules - path planning and velocity planning. The D* search method is applied in both modules, based on either geometric formulation or schedule formulation. Optimization is achieved at the individual robot level by defining cost functions to minimize, and also at the team level by a global measurement function reflecting performance indices of interest as a team. Contrary to our knowledge of previous results on multi-robot motion planning that either obtain optimal solutions through centralized and exhaustive computing, or achieve distributed implementations without considering any optimization issues, our approach combines these two features and explicitly optimizes performance functions through a distributed implementation. It is also one of the few that is capable of handling outdoor rough terrain environments and real time replanning. Simulations are shown on a Mars-like rough terrain using a 3D vehicle planner and control simulator. The algorithm was also implemented and successfully run on a group of Nomad 200 indoor robots. C1 Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. EM guoy@ornl.gov; parkerle@ornl.gov NR 29 TC 9 Z9 9 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 2612 EP 2619 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200412 ER PT B AU Dixon, WE de Queiroz, MS Dawson, DM AF Dixon, WE de Queiroz, MS Dawson, DM GP IEEE IEEE IEEE TI Adaptive racking and regulation of a wheeled mobile robot with controller/update law modularity SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc ID RIGID-LINK; MANIPULATORS; TRACKING; STABILIZATION; PASSIVITY; SYSTEMS; DESIGN AB In this paper, we develop an adaptive torque control input for Wheeled Mobile Robots (WMRs) that can be utilized in a modular manner with parameter estimate update laws to enable unified tracking and regulation. That is, provided a prediction error-based update law ensures the parameter estimate vector is bounded, all of the signals are proven to be bounded. An additional stability analysis is provided to prove that if the adaptive update law is designed such that the prediction error is square-integrable and the estimated inertia matrix is positive-definite, the WMR tracking and regulation errors are globally asymptotically forced to a control term that can be made arbitrarily small. C1 Oak Ridge Natl Lab, Engn Sci & Technol Div Robot, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Engn Sci & Technol Div Robot, Oak Ridge, TN 37831 USA. EM dixonwe@ornl.gov; dequeiroz@alpha2.eng.lsu.edu; ddawson@ces.clemson.edu NR 27 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 2620 EP 2625 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200413 ER PT B AU Moorehead, SJ AF Moorehead, SJ GP IEEE IEEE IEEE TI Autonomous exploration of cliff faces using multiple information metrics SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc AB Recent evidence that water flowed down the faces of some Martian cliffs has created an interest in the scientific community to explore these cliffs more thoroughly, perhaps using robots. This paper presents a technique for autonomous exploration that considers multiple forms of information while exploring. The method is applied to the problem of autonomously exploring cliffs. The exploring robot seeks out unknown terrain and identifies any cliffs in the environment. Men a cliff is found, the robot finds a way to the bottom to view the face of the cliff where signs of water run off may be present. Results from experiments in simulation and in the field are presented. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Moorehead, SJ (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 2668 EP 2673 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200421 ER PT B AU Gleason, SS Abidi, MA Sari-Sarraf, H AF Gleason, SS Abidi, MA Sari-Sarraf, H GP IEEE IEEE IEEE TI Probabilistic shape and appearance model for scene segmentation SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc AB Effective image segmentation of a digitized scene into a set of recognizable objects requires the development of sophisticated scene analysis algorithms. Progress in this area has been made through the development of a statistical-based deformable model that improves upon existing point distribution models (PDMs) for boundary-based object segmentation. Existing PDM boundary finding techniques often suffer from the shortcoming that global shape and gray-level information are treated independently during boundary optimization. A new deformable model algorithm is under development in which the objective function used during optimization of the boundary encompasses several important characteristics. Most importantly the objective function includes both shape and gray-level characteristics, so optimization occurs with respect to both pieces of information simultaneously. This new algorithm has been applied to geometric test images and a simple industrial-type scene for which results are presented. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Gleason, SS (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 2982 EP 2987 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200471 ER PT B AU Noakes, MW Love, LJ Lloyd, PD AF Noakes, MW Love, LJ Lloyd, PD GP IEEE IEEE IEEE TI Telerobotic planning and control for DOE D&D operations SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc AB The purpose of this paper is to describe the development of a telerobotic system focused on addressing the complex tasks found in real-world deactivation and decommissioning (D&D) activities for the Department of Energy. Because of the large gap between the conditions and constraints required to implement robotic systems and the conditions encountered in in situ D&D work, nearly all D&D activities that are too hazardous for direct human contact are presently executed using purely teleoperated remote systems. However, teleoperation is slow, expensive, and skill-intensive compared to hands-on task execution. Various model-based schemes and sensor-based enhancements have been previously tried to improve remote systems efficiencies or to permit robotic deployment; however, none meet the capability requirements necessary, other than very narrow task deployment due to restricted ability to operate in the complex unstructured real world. Advances in capability and efficiency can be achieved by developing new telerobotic control methodologies that integrate tasks ideally suited for robotic control with task definitions provided by more traditional teleoperated control. The objectives are to reduce task execution time, reduce the required operator skill level, and to enable the use of tools that are not suited for purely teleoperated control. C1 Oak Ridge Natl Lab, Engn Sci & Technol Div, Oak Ridge, TN 37831 USA. RP Noakes, MW (reprint author), Oak Ridge Natl Lab, Engn Sci & Technol Div, Oak Ridge, TN 37831 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 3485 EP 3492 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200551 ER PT B AU Madhavan, R Durrant-Whyte, H Dissanayake, G AF Madhavan, R Durrant-Whyte, H Dissanayake, G GP IEEE IEEE IEEE TI Natural landmark-based autonomous navigation using curvature scale space SO 2002 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS I-IV, PROCEEDINGS LA English DT Proceedings Paper CT 19th IEEE International Conference on Robotics and Automation (ICRA) CY MAY 11-15, 2002 CL WASHINGTON, DC SP IEEE Robot & Automat Soc DE landmark extraction; extended Kalman filter; scale space; outdoor localization AB This paper describes a terrain-aided navigation system that employs points of maximum curvature extracted from laser scan data as primary landmarks. A scale space method is used to extract points of maximum curvature from laser range scans of unmodified outdoor environments. This information is then fused with odometric information to provide localization information for an outdoor vehicle. The method described is invariant to the size and orientation of the range images under consideration (with respect to rotation and translation), is robust to noise, and can reliably detect and localize naturally occurring landmarks in the operating environment. The algorithm is demonstrated in the application of a road vehicle in an unmodified operating domain. C1 Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Comp Sci & Math Div, POB 2008, Oak Ridge, TN 37831 USA. EM raj_madhavan@yahoo.com; hugh@acfr.usyd.edu.au; dissa@acfr.usyd.edu.au OI Dissanayake, Gamini/0000-0002-7992-0680 NR 6 TC 6 Z9 6 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7272-7 PY 2002 BP 3936 EP 3941 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Engineering, Mechanical; Robotics SC Automation & Control Systems; Computer Science; Engineering; Robotics GA BV31M UT WOS:000178573200623 ER PT B AU Ericson, MN Rochelle, JM Bobrek, M Britton, CL Bobrek, A Blalock, BJ Schultz, R Moore, JA AF Ericson, MN Rochelle, JM Bobrek, M Britton, CL Bobrek, A Blalock, BJ Schultz, R Moore, JA GP IEEE IEEE TI 2(nd)- and 4(th)-Order Sigma Delta Modulators Fabricated in 3.3V 0.5 mu m SOS-CMOS for High-Temperature Applications(psi) SO 2002 IEEE INTERNATIONAL SOI CONFERENCE, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International SOI Conference CY OCT 07-10, 2002 CL WILLIAMSBURG, VA SP IEEE Electron Devices Soc AB A SigmaDelta modulator fabricated in 0.5mum SOS-CMOS is reported. The design incorporates two 2(nd)-order loops allowing reconfigurability as either a 2nd-order single loop or a 4(th)-order 2-2 cascade. Test results of the both modulator configurations over a temperature range of 25degreesC-200degreesC are presented. The modulator achieves an effective resolution of 15.5 bits resolution at 25degreesC and 13.5 bits at 200degreesC (both at 2KS/s). Design details pertaining to topological selection and device sizing is presented with an emphasis on temperature tolerance. Results of modulator noise analysis is presented along with techniques for improving the modulator noise performance. This paper reports the first 4(th)-order SigmaDelta modulator fabricated in an SOI/SOS process. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ericson, MN (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7439-8 PY 2002 BP 75 EP 77 PG 3 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Condensed Matter SC Engineering; Instruments & Instrumentation; Physics GA BV40Q UT WOS:000178854400027 ER PT B AU Qi, JY Huesman, RH AF Qi, JY Huesman, RH GP IEEE IEEE TI List mode reconstruction for PET with motion compensation: A simulation study SO 2002 IEEE INTERNATIONAL SYMPOSIUM ON BIOMEDICAL IMAGING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Symposium on Biomedical Imaging CY JUL 07-10, 2002 CL WASHINGTON, D.C. SP IEEE Signal Processing Sco, Engn Med & Biol Soc ID SYSTEM AB Motion artifacts can be a significant factor that limits the image quality in high-resolution PET. Surveillance systems have been developed to track the movements of the subject during a scan. Development of reconstruction algorithms that are able to compensate for the subject motion will increase the potential of PET. In this paper we present a list mode likelihood reconstruction algorithm with the ability of motion compensation. The subject motion is explicitly modeled in the likelihood function. The detections of each detector pair are modeled as a Poisson process with time-varying rate function. The proposed method has several advantages over the existing methods. It uses all detected events and does not introduce any interpolation error. Computer simulations show that the proposed method can compensate simulated subject movements and that the reconstructed images have no visible motion artifacts. C1 Lawrence Berkeley Natl Lab, Dept Funct Imaging, Berkeley, CA 94720 USA. RP Qi, JY (reprint author), Lawrence Berkeley Natl Lab, Dept Funct Imaging, Berkeley, CA 94720 USA. RI Qi, Jinyi/A-1768-2010 OI Qi, Jinyi/0000-0002-5428-0322 NR 11 TC 1 Z9 1 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7584-X PY 2002 BP 413 EP 416 PG 4 WC Engineering, Biomedical; Engineering, Electrical & Electronic; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA BV15G UT WOS:000178000400104 ER PT B AU Holtom, GR Colson, SD Thrall, BD AF Holtom, GR Colson, SD Thrall, BD GP IEEE IEEE TI Locating molecules using optical microscopy: 3-D imaging by Coherent Anti-Stokes Raman Scattering SO 2002 IEEE INTERNATIONAL SYMPOSIUM ON BIOMEDICAL IMAGING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Symposium on Biomedical Imaging CY JUL 07-10, 2002 CL WASHINGTON, D.C. SP IEEE Signal Processing Sco, Engn Med & Biol Soc AB Most microscopy methods do not directly reveal the chemical identity responsible for image formation. Fluorescence imaging, resulting from either intrinsic species or added dyes, is molecule specific but generally does not reveal bulk species. All chemical species have a characteristic Raman spectrum. We demonstrate a nonlinear microscopy method that provides a new solution to the problems of signal level and background fluorescence present in Raman microscopy. Signal production is due to vibrational, not electronic, resonances. Unlike fluorescence microscopy, Coherent Anti-Stokes Raman Scattering, or CARS, is resistant to photobleaching. Live cell imaging is performed routinely. Like other multiphoton microscopy methods, 3-D images are created by scanning the focal region of the laser beams through the sample. C1 Battelle Mem Inst, Pacific NW Natl Labs, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Holtom, GR (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, Environm Mol Sci Lab, Richland, WA 99352 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7584-X PY 2002 BP 781 EP 784 PG 4 WC Engineering, Biomedical; Engineering, Electrical & Electronic; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA BV15G UT WOS:000178000400196 ER PT B AU Daly, DS Wind, RA Majors, PD Anderson, KK Holtom, GR Ackerman, EJ AF Daly, DS Wind, RA Majors, PD Anderson, KK Holtom, GR Ackerman, EJ GP IEEE IEEE TI An integrated confocal and magnetic resonance microscope for observing living cells SO 2002 IEEE INTERNATIONAL SYMPOSIUM ON BIOMEDICAL IMAGING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Symposium on Biomedical Imaging CY JUL 07-10, 2002 CL WASHINGTON, D.C. SP IEEE Signal Processing Sco, Engn Med & Biol Soc ID IMAGE FUSION AB We have combined a confocal fluorescence optical microscope and a magnetic resonance microscope into one instrument, to image simultaneously a living cell system. The high spatial resolution confocal and high spectral resolution magnetic resonance microscope produces a set of closely linked, complementary images. To enhance the value of this image set, we have also developed a statistical method, local linear modeling, to predict a high spatial resolution magnetic resonance image from the confocal optical and magnetic resonance image pair. This high spatial, high spectral resolution image offers insights not available in images obtained from separate studies, nor available in the viewing the image pair as is. This paper presents first results from application of this instrument and local linear modeling, a statistical prediction technique, to a calibration phantom and a Xenopus laevis oocyte cluster. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Daly, DS (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, 902 Battelle Blvd, Richland, WA 99352 USA. OI Anderson, Kevin/0000-0001-5613-5893 NR 14 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7584-X PY 2002 BP 801 EP 804 PG 4 WC Engineering, Biomedical; Engineering, Electrical & Electronic; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA BV15G UT WOS:000178000400201 ER PT B AU George, J Rector, D Kenyon, G Schmidt, D Travis, B Wood, CC AF George, J Rector, D Kenyon, G Schmidt, D Travis, B Wood, CC GP IEEE IEEE TI Dynamic imaging of brain function: Toward convergence with neural network simulation SO 2002 IEEE INTERNATIONAL SYMPOSIUM ON BIOMEDICAL IMAGING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Symposium on Biomedical Imaging CY JUL 07-10, 2002 CL WASHINGTON, D.C. SP IEEE Signal Processing Sco, Engn Med & Biol Soc ID IN-VIVO; LIGHT; MAGNETOENCEPHALOGRAPHY; CORTEX AB Dynamic neuroimaging techniques allow measurement of neural population responses that reflect integrated activity of the underlying networks. A range of available methods provide spatial resolution and coverage from subcellular to whole head, and the ability to probe both fast and slow processes of neural activation. We have recently imaged intrinsic optical signals that are tightly coupled to the processes of neuronal activation. We observed slow optical responses corresponding to metabolic and/or hemodynamic processes. Other, faster response components closely tracked the dynamics of electro-physiological responses. We have employed fast optical signals to visualize expected spatial patterns of physiological activation of rat somato-sensory "barrel" cortex. Optical signals showed evidence of high frequency structure correlated with synchronous oscillatory activity observed in simultaneous electrical recordings. In order to account for interesting neural dynamic behavior, we are developing simulation tools that allow us to predict experimentally observable responses of neural populations. We will use these capabilities to generate testable hypotheses, and to optimize network models that account for observed dynamic responses. C1 Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM 87545 USA. RP George, J (reprint author), Los Alamos Natl Lab, Biophys Grp, Mail Stop D454, Los Alamos, NM 87545 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7584-X PY 2002 BP 1059 EP 1062 PG 4 WC Engineering, Biomedical; Engineering, Electrical & Electronic; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA BV15G UT WOS:000178000400268 ER PT S AU Omenetto, FG Efimov, A Taylor, AJ Knight, JC Wadsworth, WJ Arriaga, J Russell, PSJ AF Omenetto, FG Efimov, A Taylor, AJ Knight, JC Wadsworth, WJ Arriaga, J Russell, PSJ GP IEEE IEEE TI Ultrafast nonlinear optics in conventional and photonic crystal fibers SO 2002 IEEE/LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 15th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society CY NOV 10-14, 2002 CL GLASGOW, SCOTLAND SP IEEE Lasers & Electro Opt Soc AB Nonlinear effects play a central role in the propagation of ultrafast pulses in optical fibers. Various effects occurring during femtosecond pulse propagation in telecommunications and photonic crystal fibers will be addressed. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Omenetto, FG (reprint author), Los Alamos Natl Lab, MST-10,MS K764, Los Alamos, NM 87545 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-7500-9 J9 IEEE LEOS ANN MTG PY 2002 BP 17 EP 18 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BV68X UT WOS:000179772700008 ER PT S AU Smith, AV Armstrong, DJ AF Smith, AV Armstrong, DJ GP IEEE IEEE TI Design and performance of an image-rotating, nanosecond optical parametric oscillator SO 2002 IEEE/LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 15th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society CY NOV 10-14, 2002 CL GLASGOW, SCOTLAND SP IEEE Lasers & Electro Opt Soc AB Our goal is an efficient, high pulse energy, nanosecond optical parametric oscillator with good beam quality. We find that including 90degrees image rotation in the cavity helps achieve this performance. C1 Sandia Natl Labs, Dept 1118, Albuquerque, NM 87185 USA. RP Smith, AV (reprint author), Sandia Natl Labs, Dept 1118, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-7500-9 J9 IEEE LEOS ANN MTG PY 2002 BP 149 EP 150 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BV68X UT WOS:000179772700073 ER PT S AU Maitland, DJ Wilson, T Schumann, DL Baer, G AF Maitland, DJ Wilson, T Schumann, DL Baer, G GP IEEE IEEE TI Laser-activated shape memory polymer microactuators for treating stroke SO 2002 IEEE/LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 15th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society CY NOV 10-14, 2002 CL GLASGOW, SCOTLAND SP IEEE Lasers & Electro Opt Soc ID RHEOLYTIC CATHETER; THROMBECTOMY AB We present interventional devices for treating ischemic stroke. The development and testing of two complementary devices is proposed: a mechanical clot extraction system and a neurovascular stent. These devices are laser-activated shape memory polymer microactuators. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Maitland, DJ (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-7500-9 J9 IEEE LEOS ANN MTG PY 2002 BP 359 EP 360 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BV68X UT WOS:000179772700179 ER PT S AU Colston, B Visuri, S McBride, M Rao, R Richards, J Chuang, F Chang, J Carlson, J Derlet, R AF Colston, B Visuri, S McBride, M Rao, R Richards, J Chuang, F Chang, J Carlson, J Derlet, R GP IEEE IEEE TI Microbead immunoassay dipstick system (MIDS) SO 2002 IEEE/LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 15th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society CY NOV 10-14, 2002 CL GLASGOW, SCOTLAND SP IEEE Lasers & Electro Opt Soc C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Colston, B (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-7500-9 J9 IEEE LEOS ANN MTG PY 2002 BP 363 EP 364 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BV68X UT WOS:000179772700181 ER PT S AU Carter, JC Wilson, TS Clarey, M Stefan, P Brown, SB Alvis, RM McBride, MT Langry, K Maitland, DJ Colston, BW AF Carter, JC Wilson, TS Clarey, M Stefan, P Brown, SB Alvis, RM McBride, MT Langry, K Maitland, DJ Colston, BW GP IEEE IEEE TI M.i.DAS (Micro-Dot array sensor): Toward a rapid, in-vivo, reproducible, multianalyte biosensor using inkjet printing technology SO 2002 IEEE/LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 15th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society CY NOV 10-14, 2002 CL GLASGOW, SCOTLAND SP IEEE Lasers & Electro Opt Soc AB The Microdot Array Sensor platform for making optical fiber-based sensors using inkjet printing technology is a paradigm shifting technology for delivering low cost, rapid, in-vivo, reproducible, multianalyte biosensors. A fast-response, reproducible, pH sensor is demonstrated. C1 Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94550 USA. RP Carter, JC (reprint author), Lawrence Livermore Natl Lab, Med Technol Program, 7000 E Ave,Mailstop L-174, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-7500-9 J9 IEEE LEOS ANN MTG PY 2002 BP 365 EP 366 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BV68X UT WOS:000179772700182 ER PT S AU Vawter, GA AF Vawter, GA GP IEEE IEEE TI Adiabatic tapered mode converter for selectively-oxidized waveguide devices SO 2002 IEEE/LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 15th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society CY NOV 10-14, 2002 CL GLASGOW, SCOTLAND SP IEEE Lasers & Electro Opt Soc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Vawter, GA (reprint author), Sandia Natl Labs, MS 0603,POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-7500-9 J9 IEEE LEOS ANN MTG PY 2002 BP 546 EP 547 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BV68X UT WOS:000179772700272 ER PT S AU DiMauro, LF AF DiMauro, LF GP IEEE IEEE TI The scaling of an intense field nonlinear interaction SO 2002 IEEE/LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2 SE IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting LA English DT Proceedings Paper CT 15th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society CY NOV 10-14, 2002 CL GLASGOW, SCOTLAND SP IEEE Lasers & Electro Opt Soc C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP DiMauro, LF (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1092-8081 BN 0-7803-7500-9 J9 IEEE LEOS ANN MTG PY 2002 BP 782 EP 782 PG 1 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BV68X UT WOS:000179772700389 ER PT S AU Hurley, R Sloan, G AF Hurley, R Sloan, G BE Hamilton, R TI An L-Band, LTCC frequency doubler using embedded lumped element filters SO 2002 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-3 SE IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE MTT-S International Microwave Symposium CY JUN 02-07, 2002 CL SEATTLE, WA SP IEEE, MTTS AB We have demonstrated an L-Band frequency doubler (1.5 GHZ, 33% BW) using an LTCC (Low Temperature Co-fired Ceramic) substrate. Lumped element filters were embedded in an LTCC carrier, providing greater than 10:1 footprint reduction over a previous single-layer hybrid implementation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hurley, R (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-645X BN 0-7803-7239-5 J9 IEEE MTT-S PY 2002 BP 1549 EP 1552 PG 4 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA BV24N UT WOS:000178310900362 ER PT B AU Renner, JL AF Renner, JL GP IEEE IEEE TI Geothermal energy in the United States SO 2002 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, VOLS 1-3, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 21-25, 2002 CL CHICAGO, IL SP IEEE Power Engn Soc C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. RP Renner, JL (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. NR 0 TC 0 Z9 0 U1 2 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7518-1 PY 2002 BP 12 EP 14 PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA BW77J UT WOS:000183129700005 ER PT B AU Nix, RG AF Nix, RG GP IEEE IEEE TI Geothermal conversion plant - An engineer's perspective SO 2002 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, VOLS 1-3, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 21-25, 2002 CL CHICAGO, IL SP IEEE Power Engn Soc C1 Natl Renewable Energy Lab, Golden, CO USA. RP Nix, RG (reprint author), Natl Renewable Energy Lab, Golden, CO USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7518-1 PY 2002 BP 17 EP 18 PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA BW77J UT WOS:000183129700007 ER PT B AU Boenig, HJ Mielke, CH Burley, BL Chen, H Waynert, JA Willis, JO AF Boenig, HJ Mielke, CH Burley, BL Chen, H Waynert, JA Willis, JO GP IEEE IEEE TI The bridge-type fault current controller - A new FACTS controller SO 2002 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, VOLS 1-3, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 21-25, 2002 CL CHICAGO, IL SP IEEE Power Engn Soc DE current controller; FACTS Controller; fault current limiter; solid-state ac circuit breaker; variable inductor AB The operation of a novel current controller, which can also function as a fault current limiter and as a solid-state ac circuit breaker, is presented. The controller, which consists of a thyristor bridge, an inductor, and an optional bias power supply, is installed in series with the voltage source and the load. For load current values smaller than a preset value, the inductor of the current controller presents no impedance to the ac current flow. For values higher than the preset current value, the inductor is switched automatically into the ac circuit and limits the amount of current flow. Theoretical results in the form of circuit simulations and experimental results with a single-phase unit, operating on a 13.7 kV three-phase system with peak short-circuit currents of 3140 Arms, are presented. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Boenig, HJ (reprint author), Los Alamos Natl Lab, MS E536, Los Alamos, NM 87545 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7518-1 PY 2002 BP 455 EP 460 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA BW77J UT WOS:000183129700111 ER PT B AU Overholt, PN AF Overholt, PN GP IEEE IEEE TI A consortium for electric reliability technology research under competition SO 2002 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, VOLS 1-3, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 21-25, 2002 CL CHICAGO, IL SP IEEE Power Engn Soc C1 US DOE, Washington, DC 20585 USA. RP Overholt, PN (reprint author), US DOE, Washington, DC 20585 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7518-1 PY 2002 BP 1716 EP 1717 PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA BW77J UT WOS:000183129700383 ER PT B AU Marnay, C AF Marnay, C GP IEEE IEEE TI The California climate action registry SO 2002 IEEE POWER ENGINEERING SOCIETY WINTER MEETING, VOLS 1 AND 2, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Winter Meeting of the IEEE-Power-Engineering-Society CY JAN 27-31, 2002 CL NEW YORK, NY SP IEEE Power Engn Soc C1 Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Marnay, C (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7322-7 PY 2002 BP 111 EP 112 PG 2 WC Energy & Fuels; Engineering, Multidisciplinary SC Energy & Fuels; Engineering GA BV37Q UT WOS:000178748500020 ER PT B AU Elliott, D AF Elliott, D GP IEEE IEEE TI Assessing the world's wind resources SO 2002 IEEE POWER ENGINEERING SOCIETY WINTER MEETING, VOLS 1 AND 2, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Winter Meeting of the IEEE-Power-Engineering-Society CY JAN 27-31, 2002 CL NEW YORK, NY SP IEEE Power Engn Soc C1 Natl Renewable Energy Lab, Golden, CO USA. RP Elliott, D (reprint author), Natl Renewable Energy Lab, Golden, CO USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7322-7 PY 2002 BP 346 EP 347 PG 2 WC Energy & Fuels; Engineering, Multidisciplinary SC Energy & Fuels; Engineering GA BV37Q UT WOS:000178748500066 ER PT B AU Dougherty, P AF Dougherty, P GP IEEE IEEE TI Wind powering America SO 2002 IEEE POWER ENGINEERING SOCIETY WINTER MEETING, VOLS 1 AND 2, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Winter Meeting of the IEEE-Power-Engineering-Society CY JAN 27-31, 2002 CL NEW YORK, NY SP IEEE Power Engn Soc C1 US DOE, Wind Powering Amer Initiat, Washington, DC 20585 USA. RP Dougherty, P (reprint author), US DOE, Wind Powering Amer Initiat, Washington, DC 20585 USA. NR 0 TC 0 Z9 0 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7322-7 PY 2002 BP 350 EP 351 PG 2 WC Energy & Fuels; Engineering, Multidisciplinary SC Energy & Fuels; Engineering GA BV37Q UT WOS:000178748500068 ER PT B AU Vizkelethy, G Doyle, BL McDaniel, FD Rossi, P Dodd, PE AF Vizkelethy, G Doyle, BL McDaniel, FD Rossi, P Dodd, PE GP IEEE IEEE TI High LET radiation effects microscopy for ICS SO 2002 IEEE RADIATION EFFECTS DATA WORKSHOP, WORKSHOP RECORD LA English DT Proceedings Paper CT IEEE Radiation Effects Data Workshop held in Conjunction with IEEE Nuclear and Space Radiation Effects Conference (NSREC 2002) CY JUL 15-19, 2002 CL PHOENIX, AZ SP IEEE Nucl & Plasma Sci Soc, Inst Elect Engineers Inc AB Radiation Effects Microscopy (IREM) has been used at Sandia National Laboratories (SNL) for several years to study radiation hard ICs. As ICs become more radiation hardened, ions with larger linear energy transfer (LET) are needed to study their response to radiation. This higher LET can be achieved by using high energy, heavy ions. To carry out REM on ICs, the ion beam has to be focused to a submicron spot, which is very problematic for these ions. A new high LET system was developed at SNL, which combines two entirely new concepts in accelerator physics and nuclear microscopy. A Radio Frequency Quadrupole (RFQ) Linac is used to boost the energy of ions accelerated by a conventional Tandem Van de Graaff Pelletron to velocities of 1.9 MeV/amu. To circumvent the problem of focusing high-energy ions, we invented Ion-Electron Emission Microscopy (IEEM). Instead of focusing the ion beam and scanning it over the device under test (DUT), the positions of the ion hits are determined by projecting ion-induced secondary electrons at high magnification onto a single-electron position sensitive detector (PSD). Then, the two position signals (x and y) are recorded in coincidence with each REM event. Details of the RFQ booster and the IEEM system are given with initial results on Sandia manufactured radiation hardened ICs. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Vizkelethy, G (reprint author), Sandia Natl Labs, POB 5800,MS-1056, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7544-0 PY 2002 BP 165 EP 170 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Physics, Applied; Physics, Nuclear SC Engineering; Nuclear Science & Technology; Physics GA BV56D UT WOS:000179347500025 ER PT B AU McCready, SS Harlow, TH Heger, AS Holbert, KE AF McCready, SS Harlow, TH Heger, AS Holbert, KE GP IEEE IEEE TI Piezoresistive micromechanical transducer operation in a pulsed neutron and gamma ray environment SO 2002 IEEE RADIATION EFFECTS DATA WORKSHOP, WORKSHOP RECORD LA English DT Proceedings Paper CT IEEE Radiation Effects Data Workshop held in Conjunction with IEEE Nuclear and Space Radiation Effects Conference (NSREC 2002) CY JUL 15-19, 2002 CL PHOENIX, AZ SP IEEE Nucl & Plasma Sci Soc, Inst Elect Engineers Inc DE piezoresistive; transducer; accelerometer; pressure; temperature; microelectromechanical; MEMS; radiation ID ACCELEROMETER; MEMS; RADIATION AB We completed the third in a series of experiments using commercially available, piezoresistive microelectromechanical system (MEMS) transducers to instrument articles exposed to the intense, pulsed neutron and gamma ray radiation environment of Sandia National Laboratories' Annular Core Research Reactor. Based on analyzing the survival of pressure transducers and accelerometers in the first two experiments, we identified candidate piezoresistive, MEMS transducers and then tested them by exposure to pulses, each with 10(15) neutrons/cm' and 10(4) Gy (1 Mrad) of gamma radiation. Simultaneous measurement of temperature indicates that the pressure transducers retain their calibrations and may provide a means of quickly identifying temperature-induced offset shifts of accelerometer calibrations. Comparison to other sensors that do not survive in this environment and implications for using these transducers to instrument test articles are also presented. C1 Los Alamos Natl Lab, WR, ESA, Los Alamos, NM 87545 USA. RP McCready, SS (reprint author), Los Alamos Natl Lab, WR, ESA, Los Alamos, NM 87545 USA. NR 11 TC 1 Z9 1 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7544-0 PY 2002 BP 181 EP 186 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology; Physics, Applied; Physics, Nuclear SC Engineering; Nuclear Science & Technology; Physics GA BV56D UT WOS:000179347500028 ER PT S AU Telschow, KL Deason, VA Cottle, DL Larson, JD AF Telschow, KL Deason, VA Cottle, DL Larson, JD BE Yuhas, DE Schneider, SC TI Full-field Imaging of acoustic motion at nanosecond time and micron length scales SO 2002 IEEE ULTRASONICS SYMPOSIUM PROCEEDINGS, VOLS 1 AND 2 SE ULTRASONICS SYMPOSIUM LA English DT Proceedings Paper CT IEEE International Ultrasonic Symposium CY OCT 08-11, 2002 CL MUNICH, GERMANY SP IEEE Ultrason, Ferroelect & Frequency Control Soc ID INTERFEROMETER; WAVES AB A full-field view laser ultrasonic imaging method has been developed that measures acoustic motion at a, surface without scanning. Images are recorded at normal video frame rates by employing dynamic holography using photorefractive interferometric detection. By extending the approach to ultra high frequencies, an acoustic microscope has been developed capable of operation on the nanosecond time and micron length scales. Both acoustic amplitude and phase are recorded allowing full calibration and determination of phases to within a single arbitrary constant. Results are presented of measurements at frequencies at 800-900 MHz illustrating a multitude of normal mode behavior in electrically driven thin film acoustic resonators. :Coupled with microwave electrical impedance measurements, this imaging mode provides an exceptionally fast method for evaluation of electric to acoustic coupling and performance of these devices. Images of 256x240 pixels are recorded at 18Hz rates synchronized to obtain both in-phase and quadrature detection of the acoustic motion. Simple averaging provides sensitivity to the subnanometer level calibrated over the image using interferometry. Identification of specific acoustic modes and their relationship to electrical impedance characteristics show the advantages and overall high speed of the technique. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Telschow, KL (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 6 TC 3 Z9 3 U1 0 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1051-0117 BN 0-7803-7582-3 J9 ULTRASON PY 2002 BP 601 EP 604 DI 10.1109/ULTSYM.2002.1193474 PG 4 WC Acoustics; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Acoustics; Engineering; Instruments & Instrumentation GA BW47M UT WOS:000182111700132 ER PT B AU Hammond, S AF Hammond, S GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI The role of computational science in energy efficiency and renewable energy SO 2002 INTERNATIONAL CONFERENCE ON PARALLEL ARCHITECTURES AND COMPILATION TECHNIQUES, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel Architectures and Compilation Techniques CY SEP 22-25, 2002 CL CHARLOTTESVILLE, VA SP IEEE Comp Soc, Tech Comm Comp Architecture, IEEE Comp Soc, Tech Comm Parallel Processing, ACM Special Interest Grp Comp Architecture, IFIP WG 10 3, IBM, Microsoft Res, Univ Virginia, Dept Comp Sci C1 Natl Renewable Energy Lab, Sci & Technol Directorate, Golden, CO 80401 USA. RP Hammond, S (reprint author), Natl Renewable Energy Lab, Sci & Technol Directorate, Golden, CO 80401 USA. NR 0 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 0-7695-1620-3 PY 2002 BP 117 EP 117 PG 1 WC Computer Science, Hardware & Architecture SC Computer Science GA BV36Q UT WOS:000178711200011 ER PT S AU Feng, W Warren, M Weigle, E AF Feng, W Warren, M Weigle, E BE Abdelrahman, TS TI Honey, I shrunk the Beowulf! SO 2002 INTERNATIONAL CONFERENCE ON PARALLEL PROCESSING, PROCEEDING SE Proceedings of the International Conference on Parallel Processing LA English DT Proceedings Paper CT 31st International Conference on Parallel Processing (ICPP 2002) CY AUG 18-21, 2002 CL VANCOUVER, CANADA SP Int Assoc Comp & Commun, Ohio State Univ, IBM Res, Microsoft Res, James Madison Univ, CISC DE Beowulf; cluster; blade server; RLX; Trans-meta; code morphing; VLIW; NAS benchmarks; price-performance ratio; ToPPeR; performance-space ratio; performance-power ratio; n-body code; treecode AB In this paper we present a novel twist on the Beowulf cluster - the Bladed Beowulf Designed by RLX Technologies and integrated and configured at Los Alamos National Laboratory, our Bladed Beowulf consists of compute nodes made from commodity off-the-shelf parts mounted on motherboard blades measuring 14.7" x 4.7" x 0.58". Each motherboard blade (node) contains a 633-MHz Transmeta TM5600(TM) CPU, 256-MB memory, 10-GB hard disk, and three 100-Mb/s Fast Ethernet network interfaces. Using a chassis provided by RLX, twenty-four such nodes mount side-by-side in a vertical orientation to fit in a rack-mountable 3 U space, i.e., 19" in width and 5.25" in height. A Bladed Beowulf can reduce the total cost of ownership (TCO) of a traditional Beowulf by a factor of three while providing Beowulf-like performance. Accordingly, rather than use the traditional definition of price-performance ratio where price is the cost of acquisition, we introduce a new metric called ToPPeR: Total Price-Performance Ratio, where total price encompasses TCO. We also propose two related (but more concrete) metrics: performance-space ratio and performance-power ratio. C1 Los Alamos Natl Lab, Comp & Computat Sci Div, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Comp & Computat Sci Div, Los Alamos, NM 87545 USA. EM feng@lanl.gov; msw@lanl.gov; ehw@lanl.gov NR 11 TC 1 Z9 1 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 SN 0190-3918 BN 0-7695-1677-7 J9 PROC INT CONF PARAL PY 2002 BP 141 EP 148 DI 10.1109/ICPP.2002.1040868 PG 8 WC Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV03Y UT WOS:000177666900015 ER PT S AU Van de Sompel, H Bergmark, D AF Van de Sompel, H Bergmark, D BE Olariu, S TI A distributed registry for OpenURL metadata schemas with an OAI-PMH conformant central repository SO 2002 INTERNATIONAL CONFERENCE ON PARALLEL PROCESSING, PROCEEDINGS OF THE WORKSHOPS SE International Conference on Parallel Processing Workshops LA English DT Proceedings Paper CT 31st International Conference on Parallel Processing (ICPP 2002) CY AUG 18-21, 2002 CL VANCOUVER, CANADA SP Int Assoc Comp & Commun, Ohio State Univ, IBM Res, Microsoft Res, James Madison Univ, CISC AB This paper describes a distributed registry of XML Schemas in which a central facility uses the Open Archives Protocol for Metadata Harvesting (OAI-PMH) as a communication mechanism between registrars and parties that need to remain up-to-date regarding registration, updating and deregistration of those Schemas. This novel application of the OAI-PMH is described in the context of registration of XML Schema for usage in OpenURL applications, It suggests the applicability of the protocol in areas that go well beyond resource discovery, and that may actually reach into the realm of synchronization of administrative networked processes, and digital preservation. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. EM herbertv@lanl.gov; bergmark@cs.cornell.edu NR 5 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 SN 1530-2016 BN 0-7695-1680-7 J9 INT CONF PARA PROC PY 2002 BP 469 EP 472 DI 10.1109/ICPPW.2002.1039767 PG 4 WC Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV03Z UT WOS:000177667600061 ER PT S AU Chanchio, K Sun, XH AF Chanchio, K Sun, XH BE Olariu, S TI SNOW: Software systems for process migration in high-performance, heterogeneous distributed environments SO 2002 INTERNATIONAL CONFERENCE ON PARALLEL PROCESSING, PROCEEDINGS OF THE WORKSHOPS SE International Conference on Parallel Processing Workshops LA English DT Proceedings Paper CT 31st International Conference on Parallel Processing (ICPP 2002) CY AUG 18-21, 2002 CL VANCOUVER, CANADA SP Int Assoc Comp & Commun, Ohio State Univ, IBM Res, Microsoft Res, James Madison Univ, CISC AB This paper reports our experiences on the Scalable Network of Workstation (SNOW) project, which implements a novel methodology to support user-level process migration for traditional stack-based languages such as C and Fortran in heterogeneous distributed environments. Our methodology addresses the three outstanding problems of transferring execution state, memory state, and communication state. The concepts of migration point analysis and buffered data transfer mechanism are proposed for execution state migration. A memory space representation model is introduced to obtain the machine-independent format of the underlying data structures for memory state migration. Finally, process migration and communication protocols are developed to migrate the communication state and maintain the functionality and correctness of data communication. A coordinated software system consisting of compilation and runtime systems has been developed based on these new mechanisms. The runtime systems include a runtime library and communication protocols. Sequential and parallel programs with different data structures and computing requirements are tested. Experimental results confirm our design analysis. They advocate the value of the migration methodology for distributed network computing. C1 Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37819 USA. RP Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37819 USA. EM chanchiok@ornl.gov; sun@cs.iit.edu NR 15 TC 1 Z9 1 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 SN 1530-2016 BN 0-7695-1680-7 J9 INT CONF PARA PROC PY 2002 BP 589 EP 596 DI 10.1109/ICPPW.2002.1039781 PG 8 WC Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV03Z UT WOS:000177667600075 ER PT B AU Witzke, EL Tarman, TD Ghosh, S Woodard, G AF Witzke, EL Tarman, TD Ghosh, S Woodard, G GP IEEE IEEE TI A novel scaleable architecture for intrusion detection and mitigation in switched networks SO 2002 MILCOM PROCEEDINGS, VOLS 1 AND 2: GLOBAL INFORMATION GRID - ENABLING TRANSFORMATION THROUGH 21ST CENTURY COMMUNICATIONS LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 2002) CY OCT 07-10, 2002 CL ANAHEIM, CA SP IEEE Commun Soc, AFCEA AB High-speed switched networks present scalability challenges to a network intrusion detection system, both in terms of the volume of data that must be analyzed, and the extent to which sensors must be inserted into the switched network to achieve comprehensive visibility. An architecture that uses a single point for intrusion assessment would quickly become overwhelmed with incoming event data from intrusion sensors that are deployed on even a moderate number of high-speed links. This is particularly true if an earnest,attack (generating many events in a short period of time) is underway. The authors propose a novel architecture that hierarchically distributes the assessment function into two assessment categories -- tactical assessment, and strategic assessment. The tactical assessment,function provides low-level event correlation and decision making,for a small sub-network (e.g:, a department LAN, an ATM switch peer group, etc.), and is capable of providing fast, real-time response when millisecond response times are required due to network attacks. The strategic assessment,function, on the other hand, implements high-level event correlation, which is useful when a larger view, of the network is required (e.g., for low intensity or distributed attacks). The tactical assessment engines interface to the strategic assessment engine by filtering and summarizing low-level events, ensuring that the strategic assessment engine's workload remains manageable. This paper describes the distributed intrusion assessment architecture in more detail, presents a few application scenarios that benefit from hierarchical attack assessment, and summarizes ongoing work in developing prototype components for this architecture. C1 Sandia Natl Labs, Adv Networking Integrat Dept, Albuquerque, NM 87185 USA. RP Witzke, EL (reprint author), Sandia Natl Labs, Adv Networking Integrat Dept, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7625-0 PY 2002 BP 395 EP 399 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BW09Y UT WOS:000180880500071 ER PT B AU Feng, WC AF Feng, WC GP IEEE IEEE TI Securing wireless communication in heterogeneous environments SO 2002 MILCOM PROCEEDINGS, VOLS 1 AND 2: GLOBAL INFORMATION GRID - ENABLING TRANSFORMATION THROUGH 21ST CENTURY COMMUNICATIONS LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 2002) CY OCT 07-10, 2002 CL ANAHEIM, CA SP IEEE Commun Soc, AFCEA AB With the convergence of mobile devices and the Internet, ubiquitous computing promises to revolutionize the way that we access services and run applications. However, ubiquitous computing environments, in particular, mobile and wireless environments interfaced with the Internet, currently possess security vulnerabilities that are ripe for attack from cyber-threats. Thus, this paper discusses the limitations of current security mechanisms in ubiquitous (but heterogeneous) computing environments and presents a general-purpose infrastructure that addresses these limitations, thus allowing heterogeneous environments to communicate in a secure manner. These heterogeneous environments of the future will be interoperable and will include environments such as wireless sensor networks, mobile communication, and computational grids. C1 Los Alamos Natl Lab, Comp & Computat Sci Div, RADIANT, Los Alamos, NM 87545 USA. RP Feng, WC (reprint author), Los Alamos Natl Lab, Comp & Computat Sci Div, RADIANT, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7625-0 PY 2002 BP 1101 EP 1106 PG 6 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BW09Y UT WOS:000180880500201 ER PT B AU Buckner, M Crutcher, R Moore, MR Whitus, B AF Buckner, M Crutcher, R Moore, MR Whitus, B GP IEEE IEEE TI MICLOG RFID tag program enables total asset visibility SO 2002 MILCOM PROCEEDINGS, VOLS 1 AND 2: GLOBAL INFORMATION GRID - ENABLING TRANSFORMATION THROUGH 21ST CENTURY COMMUNICATIONS LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 2002) CY OCT 07-10, 2002 CL ANAHEIM, CA SP IEEE Commun Soc, AFCEA AB RFID tagging and tracking efforts sponsored by DLA under the MICLOG program(1) will support total asset visibility for the military. This system can be used to provide programs such as FCS with persistent knowledge of the location and status of every asset. This will provide commanders the assurance they need to verify logistics and plan missions. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Buckner, M (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7625-0 PY 2002 BP 1422 EP 1426 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BW09Y UT WOS:000180880500261 ER PT S AU Folta, JA Kearney, PA Larson, CC Crosley, MK Fisch, E Racette, KC AF Folta, JA Kearney, PA Larson, CC Crosley, MK Fisch, E Racette, KC BE Grenon, BJ Kimmel, KR TI Low-defect EUVL multilayers on standard format mask blanks SO 22ND ANNUAL BACUS SYMPOSIUM ON PHOTOMASK TECHNOLOGY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 22nd Annual BACUS Symposium on Photomask Technology CY OCT 01-04, 2002 CL MONTEREY, CA SP BACUS, SPIE, Int Tech Grp DE Extreme Ultraviolet Lithography; EUVL; next generation lithography; NGL; mask; blank; multilayer; defect ID EXTREME-ULTRAVIOLET LITHOGRAPHY AB Fabrication of low defect density mask blanks remains as one of the key challenges to commercialization of Extreme Ultraviolet Lithography (EUVL). A low defect deposition process for EUV-reflective Mo/Si multilayers has been developed on 200mm silicon substrates because of the availability of sensitive, fast defect inspection tools for wafers. A defect level of 0.05 defects/cm(2) at 90 nm defect size detection threshold can now be achieved repeatedly on wafers. We upgraded the low defect multilayer deposition (LDD) system to allow coating of standard format, 152mm square mask blanks. Mask blank defect inspection was performed at IBM with a typical sensitivity of 100 nm PSL equivalent. We used the single reticle SMIF pod (RSP) standard both for clean, automated handling and for shipping of the mask substrates and blanks. The added defect level during shipping was improved to 0.02 2 defects/cm2. We achieved a process-added defect density of 0.38 defects/cm(2) on a lot of 5 blanks; which was the same defect level as on wafers coated before and after the blanks. We also improved the reflectance and thickness control on blanks to achieve 66.5% EUV reflectance, and a thickness uniformity of 0.07% P-V or 0.04% rms. The improved reflectance and uniformity meet the SEMI P38 specifications for EUVL mask blanks. We have discovered no differences in defect levels or film quality in the coating of standard square format as compared to silicon wafers. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Folta, JA (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 12 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 0-8194-4675-0 J9 P SOC PHOTO-OPT INS PY 2002 VL 4889 BP 374 EP 381 DI 10.1117/12.467478 PN 1&2 PG 8 WC Optics SC Optics GA BV98U UT WOS:000180592500039 ER PT S AU Barty, A Taylor, JS Hudyma, R Spiller, E Sweeney, DW Shelden, G Urbach, JP AF Barty, A Taylor, JS Hudyma, R Spiller, E Sweeney, DW Shelden, G Urbach, JP BE Grenon, BJ Kimmel, KR TI Aerial image microscopes for the inspection of defects in EUV masks SO 22ND ANNUAL BACUS SYMPOSIUM ON PHOTOMASK TECHNOLOGY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 22nd Annual BACUS Symposium on Photomask Technology CY OCT 01-04, 2002 CL MONTEREY, CA SP BACUS, SPIE, Int Tech Grp DE EUV lithography; aerial image monitor; defect inspection and review C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Barty, A (reprint author), Lawrence Livermore Natl Lab, L-395,POB 808, Livermore, CA 94550 USA. NR 2 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 0-8194-4675-0 J9 P SOC PHOTO-OPT INS PY 2002 VL 4889 BP 1073 EP 1084 DI 10.1117/12.467918 PN 1&2 PG 12 WC Optics SC Optics GA BV98U UT WOS:000180592500116 ER PT B AU Maghribi, M Hamilton, J Polla, D Rose, K Wilson, T Krulevitch, P AF Maghribi, M Hamilton, J Polla, D Rose, K Wilson, T Krulevitch, P BE Dittmar, A Beebe, D TI Stretchable micro-electrode array SO 2ND ANNUAL INTERNATIONAL IEEE-EMBS SPECIAL TOPIC CONFERENCE ON MICROTECHNOLOGIES IN MEDICINE & BIOLOGY, PROCEEDINGS SE IEEE Engineering in Medicine and Biology Society Annual Conference (EMBS) LA English DT Proceedings Paper CT 2nd Annual International IEEE/EMBS Conference on Microtechnologies in Medicine and Biology CY MAY 02-04, 2002 CL MADISON, WI SP IEEE/Engn Med & Biol Soc, Natl Inst Hlth, Defense Adv Res Project Agcy, Motorola, NimbleGen Syst Inc, PanVera Corp, Dow Chem Co, GWC Instruments, Venture Invest LLC, Univ Wisconsin-Madison, Dept Biomed Engn, IEEE/Robot & Automat Soc, Promega DE retinal prosthesis; PDMS metalization; residual stress; stretchable micro-electrode array ID HIGH-RESOLUTION; LITHOGRAPHY AB This paper focuses on the design considerations, fabrication processes, and preliminary testing of a retinal prosthesis that has the potential to aid in vision restoration to millions of blind patients. We are developing an implantable, stretchable micro-electrode array using polymer-based microfabrication techniques. The device will serve as the interface between an electronic imaging system and the human eye, directly stimulating retinal neurons via thin film conducting traces and electroplated electrodes. The metal features are embedded within a thin (similar to50 mum) substrate fabricated using poly (dimethylsiloxane) (PDMS), a biocompatible elastomeric material that has high oxygen permeability and low water permeability. The conformable nature of PDMS is critical for ensuring uniform contact with the curved surface of the retina. To fabricate the device, we developed unique processes for metalizing PDMS to produce robust traces capable of maintaining conductivity when stretched (strain = 7%, SD 1), and for selectively passivating the conductive elements. An in situ substrate curvature measurement taken while curing the PDMS revealed a tensile residual strain of 10%, explaining the stretchable nature of the thin metalized devices. C1 Lawrence Livermore Natl Lab, Ctr Microtechnol, Livermore, CA USA. RP Maghribi, M (reprint author), Lawrence Livermore Natl Lab, Ctr Microtechnol, Livermore, CA USA. NR 13 TC 21 Z9 21 U1 1 U2 9 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7480-0 J9 ENG MED BIOL SOC ANN PY 2002 BP 80 EP 83 DI 10.1109/MMB.2002.1002269 PG 4 WC Biochemical Research Methods; Engineering, Biomedical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Biochemistry & Molecular Biology; Engineering; Instruments & Instrumentation GA BU48A UT WOS:000176123400016 ER PT B AU Pizarro, SA Schoeniger, JS VanderNoot, VA AF Pizarro, SA Schoeniger, JS VanderNoot, VA BE Dittmar, A Beebe, D TI Capillary-based separation microtechnologies for pattern profiling of phosphoproteins involved in T cell signaling SO 2ND ANNUAL INTERNATIONAL IEEE-EMBS SPECIAL TOPIC CONFERENCE ON MICROTECHNOLOGIES IN MEDICINE & BIOLOGY, PROCEEDINGS SE IEEE Engineering in Medicine and Biology Society Annual Conference (EMBS) LA English DT Proceedings Paper CT 2nd Annual International IEEE/EMBS Conference on Microtechnologies in Medicine and Biology CY MAY 02-04, 2002 CL MADISON, WI SP IEEE/Engn Med & Biol Soc, Natl Inst Hlth, Defense Adv Res Project Agcy, Motorola, NimbleGen Syst Inc, PanVera Corp, Dow Chem Co, GWC Instruments, Venture Invest LLC, Univ Wisconsin-Madison, Dept Biomed Engn, IEEE/Robot & Automat Soc, Promega DE phosphorylation; T lymphocyte activation; capillary electrophoresis ID PHOSPHORYLATION AB Current methods of determining pathogen exposure are bound by the proliferation of the pathogens within the bloodstream, by antibody production, or by the appearance of symptoms as the disease progresses. It is therefore advantageous in treatment, or containment, to have a technique that can detect exposure at an earlier stage. Because protein phosphorylation is an integral part of cell signaling, and one of the earliest indicators of immune system activation, phosphoproteins are an attractive target. We have used sensitive micro-analytical separation techniques, such as capillary gel electrophoresis (CGE) coupled to laser induced fluorescence detection, to probe differences in phosphoprotein populations extracted from immune cells. Using both general and specific modes of activation, we have consistently been able to differentiate between profiles or 'fingerprints' from resting and activated T cells. Further experiments are underway to determine the robustness of the method. Development of this application may lead to a tool for rapid determination of immune system activation, which can be beneficial to the medical and biological research communities. C1 Sandia Natl Labs, Biosyst Res Dept, Livermore, CA 94551 USA. RP Pizarro, SA (reprint author), Sandia Natl Labs, Biosyst Res Dept, POB 969 MS 9951, Livermore, CA 94551 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7480-0 J9 ENG MED BIOL SOC ANN PY 2002 BP 433 EP 436 DI 10.1109/MMB.2002.1002363 PG 4 WC Biochemical Research Methods; Engineering, Biomedical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Biochemistry & Molecular Biology; Engineering; Instruments & Instrumentation GA BU48A UT WOS:000176123400090 ER PT B AU Visuri, SR Ness, K Dzenitis, J Benett, B Bettencourt, K AF Visuri, SR Ness, K Dzenitis, J Benett, B Bettencourt, K BE Dittmar, A Beebe, D TI Microfluidic tools for biological sample preparation SO 2ND ANNUAL INTERNATIONAL IEEE-EMBS SPECIAL TOPIC CONFERENCE ON MICROTECHNOLOGIES IN MEDICINE & BIOLOGY, PROCEEDINGS SE IEEE Engineering in Medicine and Biology Society Annual Conference (EMBS) LA English DT Proceedings Paper CT 2nd Annual International IEEE/EMBS Conference on Microtechnologies in Medicine and Biology CY MAY 02-04, 2002 CL MADISON, WI SP IEEE/Engn Med & Biol Soc, Natl Inst Hlth, Defense Adv Res Project Agcy, Motorola, NimbleGen Syst Inc, PanVera Corp, Dow Chem Co, GWC Instruments, Venture Invest LLC, Univ Wisconsin-Madison, Dept Biomed Engn, IEEE/Robot & Automat Soc, Promega DE microfluidic; dielectrophoresis; acoustic; sample preparation; nucleic acid; immnunoassay AB Researchers at Lawrence Livermore National Laboratory are developing means to collect and identify fluid-based biological pathogens in the forms of proteins, viruses, and bacteria. To support detection instruments, we are developing a flexible fluidic sample preparation unit. The overall goal of this Microfluidic Module is to input a fluid sample, containing background particulates and potentially target compounds, and deliver a processed sample for detection. We are developing techniques for sample purification, mixing, and filtration that would be useful to many applications including immunologic and nucleic acid assays. Sample preparation functions are accomplished with acoustic radiation pressure, dielectrophoresis, and solid phase extraction. We are integrating these technologies into packaged systems with pumps and valves to control fluid flow and investigating small-scale detection methods. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Visuri, SR (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 7 TC 1 Z9 1 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7480-0 J9 ENG MED BIOL SOC ANN PY 2002 BP 556 EP 559 DI 10.1109/MMB.2002.1002410 PG 4 WC Biochemical Research Methods; Engineering, Biomedical; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Biochemistry & Molecular Biology; Engineering; Instruments & Instrumentation GA BU48A UT WOS:000176123400116 ER PT B AU Sharpe, SW Sams, RL Johnson, TJ AF Sharpe, SW Sams, RL Johnson, TJ BE Schaefer, DH TI The PNNL quantitative IR database for infrared remote sensing and hyperspectral imaging SO 31ST APPLIED IMAGERY PATTERN RECOGNITION WORKSHOP, PROCEEDINGS LA English DT Proceedings Paper CT 31st Applied Imagery Pattern Recognition Workshop CY OCT 16-18, 2002 CL WASHINGTON, D.C. SP IEEE Comp Soc ID ARTIFACTS AB Pacific Northwest National Laboratory (PNNL) is presently compiling a quantitative, high spectral resolution (0.10 cm(-1)) set of infrared reference data that are specifically designed for atmospheric monitoring, remote sensing, and hyperspectral imaging. The final list of target compounds will contain nearly 500 gas phase species, whereby each species is reported as a composite reference spectrum at 25degreesC with most species also having reference data for 5degreesC and 50degreesC. Each composite spectrum is a quantitative Beer's law fit to typically 10 or more individual infrared measurements, whereby each individual spectrum corresponds to a different partial pressure of the sample that has been pressurized to 760 Torr with N-2 so as to emulate atmospheric pressure broadening. Details of the data acquisition protocol and spectral analysis are discussed. C1 Pacific NW Natl Lab, Richland, WA USA. RP Sharpe, SW (reprint author), Pacific NW Natl Lab, Richland, WA USA. NR 9 TC 3 Z9 3 U1 0 U2 4 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1863-X PY 2002 BP 45 EP 48 PG 4 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Spectroscopy SC Computer Science; Engineering; Spectroscopy GA BW45Z UT WOS:000182079100006 ER PT B AU Becker, NM Brumby, S David, NA Irvine, JM AF Becker, NM Brumby, S David, NA Irvine, JM BE Schaefer, DH TI Analysis of multispectral imagery and modeling contaminant transport SO 31ST APPLIED IMAGERY PATTERN RECOGNITION WORKSHOP, PROCEEDINGS LA English DT Proceedings Paper CT 31st Applied Imagery Pattern Recognition Workshop CY OCT 16-18, 2002 CL WASHINGTON, D.C. SP IEEE Comp Soc AB A significant concern in the monitoring of hazardous waste is the potential for contaminants to migrate into locations where their presence poses greater environmental risks. The transport modeling performed in this study demonstrates the joint use of remotely sensed multispectral imagery and mathematical modeling to assess the surface migration of contaminants. KINEROS, an event-driven model of surface runoff and sediment transport, was used to assess uranium transport for various rain events. The model inputs include parameters related to the size and slope of watershed components, vegetation, and soil conditions. One distinct set of model inputs was derived from remotely sensed imagery data and another from site-specific knowledge. To derive the parameters of the KINEROS model from remotely sensed data, classification analysis was performed on IKONOS four-band multispectral imagery of the watershed. A system known as GENIE, developed by Los Alamos National Laboratory, employs genetics algorithms to evolve classifiers based on small, user-selected training samples. The classification analysis derived by employing GENIE provided insight into the correct KINEROS parameters for various sub-elements of the watershed. The model results offer valuable information about portions of the watershed that contributed the most to contaminant transport. These methods are applicable to numerous sites where possible transport of waste materials poses an environmental risk. Because the approach rests on the analysis of remote sensing data, the techniques can be used to monitor inaccessible waste sites, as well as reduce the amount of data that would need to be collected for model calibration. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Becker, NM (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 1 U2 2 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-1863-X PY 2002 BP 71 EP 77 PG 7 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Spectroscopy SC Computer Science; Engineering; Spectroscopy GA BW45Z UT WOS:000182079100010 ER PT S AU Holmes, VP Kleban, SD Miller, DJ Pavlakos, C Poore, CA Vandewart, RL Crowley, CP AF Holmes, VP Kleban, SD Miller, DJ Pavlakos, C Poore, CA Vandewart, RL Crowley, CP GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI An architecture and implementation to support large-scale data access in scientific simulation environments SO 35TH ANNUAL SIMULATION SYMPOSIUM, PROCEEDINGS SE PROCEEDINGS OF THE ANNUAL SIMULATION SYMPOSIA LA English DT Proceedings Paper CT 35th Annual Simulation Symposium CY APR 14-18, 2002 CL SAN DIEGO, CA SP Soc Comp Simulat Int AB At Sandia National Laboratories, a Data Services system has been developed to provide web-based access to high-performance computing clusters that host a set Of post-processing applications for very large-scale data manipulation and visualization. A three-tier architecture provides a meta-framework for a collection of smaller frameworks, each of which satisfies a particular aspect of the overall system, including frameworks for a common data model, distributed resource management, component-based software on the cluster, and security. A prototype implementation has been completed which demonstrates the use of all of these frameworks in an integrated environment to provide end users the ability to manage and understand simulation results for very large, complex problems. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Holmes, VP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 21 TC 0 Z9 0 U1 1 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1080-241X BN 0-7695-1552-5 J9 PROC ANNU SIMUL SYMP PY 2002 BP 169 EP 176 DI 10.1109/SIMSYM.2002.1000149 PG 8 WC Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BU39D UT WOS:000175881500020 ER PT B AU Smith, GJ AF Smith, GJ BE Sanson, LD TI The center for civil force protection SO 36TH ANNUAL 2002 INTERNATIONAL CARNAHAN CONFERENCE ON SECURITY TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual International Carnahan Conference on Security Technology CY OCT 20-24, 2002 CL ATLANTIC CITY, NJ SP IEEE Lexington Sect, IEEE Aerosp & Electr Syst Soc, Chung Shan Inst Sci & Technol, Natl Chiao Tung Univ, Transportat Secur Adm AB This paper describes the Center for Civil Force Protection (CCFP) which is operated by Sandia National Laboratories (SNL) to provide technical assistance to governmental organizations and communities to improve their ability to resist terrorist attacks before they occur. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Smith, GJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7436-3 PY 2002 BP 17 EP 18 DI 10.1109/CCST.2002.1049218 PG 2 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Computer Science; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA BV49P UT WOS:000179163100001 ER PT B AU Bowser, GH Piechowski, CJ Pocratsky, CA Sparks, MH AF Bowser, GH Piechowski, CJ Pocratsky, CA Sparks, MH BE Sanson, LD TI "US Department of Energy security technologies" SO 36TH ANNUAL 2002 INTERNATIONAL CARNAHAN CONFERENCE ON SECURITY TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual International Carnahan Conference on Security Technology CY OCT 20-24, 2002 CL ATLANTIC CITY, NJ SP IEEE Lexington Sect, IEEE Aerosp & Electr Syst Soc, Chung Shan Inst Sci & Technol, Natl Chiao Tung Univ, Transportat Secur Adm AB For over 40 years, the U.S. Department of Energy (DOE) has maintained a program that develops technologies to support safeguards and security policies in the protection of nuclear weapons facilities. Basic security system engineering concepts are still valid, the details of the systems at DOE facilities must constantly be updated to respond to the emerging terrorist threat and capabilities and the need to replace aging components and systems. The mission of the Technology Development Program (TDP) is overwhelmingly diverse, as it must be, to protect a wide array of critical assets such as nuclear weapons, special nuclear material in various forms, components of nuclear weapons, classified nuclear weapons design information, nuclear facilities, national laboratories, cyber systems, and U.S. energy infrastructure. Considering the fact that the nuclear weapons complex consist of dozens of facilities that are located in various regions all over the United States; and that no two facilities are alike, the TDP fulfills a very challenging role. C1 US DOE, Off Secur, Germantown, MD 20874 USA. RP Bowser, GH (reprint author), US DOE, Off Secur, Germantown, MD 20874 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7436-3 PY 2002 BP 19 EP 24 DI 10.1109/CCST.2002.1049219 PG 6 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Computer Science; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA BV49P UT WOS:000179163100002 ER PT B AU Tarman, TD Witzke, EL Pierson, LG Campbell, PL AF Tarman, TD Witzke, EL Pierson, LG Campbell, PL BE Sanson, LD TI On the use of trusted objects to enforce isolation between processes and data SO 36TH ANNUAL 2002 INTERNATIONAL CARNAHAN CONFERENCE ON SECURITY TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual International Carnahan Conference on Security Technology CY OCT 20-24, 2002 CL ATLANTIC CITY, NJ SP IEEE Lexington Sect, IEEE Aerosp & Electr Syst Soc, Chung Shan Inst Sci & Technol, Natl Chiao Tung Univ, Transportat Secur Adm DE trusted objects; faithful execution; execution correctness; encryption; encrypted objects AB This paper highlights the problem of run-time execution correctness of high-consequence applications in conventional Von Neumann computer architectures. It proposes an approach -- trusted objects -- in which the application program and data are cryptographically encapsulated in their own environment. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Tarman, TD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7436-3 PY 2002 BP 115 EP 119 DI 10.1109/CCST.2002.1049235 PG 5 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Computer Science; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA BV49P UT WOS:000179163100018 ER PT B AU Tanner, DM Walraven, JA Mani, SS Swanson, SE AF Tanner, DM Walraven, JA Mani, SS Swanson, SE GP IEEE IEEE IEEE IEEE TI Pin-joint design effect on the reliability of a polysilicon microengine SO 40TH ANNUAL PROCEEDINGS: INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM SE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM LA English DT Proceedings Paper CT 40th Annual IEEE International Reliability Physics Symposium CY APR 07-11, 2002 CL DALLAS, TX SP IEEE Electron Devices Soc, IEEE Reliabil Soc DE MicroElectroMechanical System; MEMS reliability; MEMS wear ID SURFACE MICROMACHINED MICROENGINE; PERFORMANCE AB Accelerated stress experiments were performed on a class of pin joints to determine reliability. We varied parameters that affected the area of the rubbing surfaces and the gap between those surfaces. Most of the pin joints failed due to seizure. We observed bimodal failure distributions where the lower distribution was associated with an adhesion event with no observable wear debris. The upper distribution of failures was associated with agglomerations of wear debris, which may have seized the pin joint. The effect of surface coatings was also studied. We found that for supercritical carbon dioxide (SCCO2) dried microengines; the largest effect was due to gap spacing. For microengines with a self-assembled monolayer coating (SAMS), we observed minimal difference in the lifetimes of failed devices. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Tanner, DM (reprint author), Sandia Natl Labs, POB 5800,M-S 1081, Albuquerque, NM 87185 USA. NR 23 TC 1 Z9 1 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7352-9 J9 INT REL PHY PY 2002 BP 122 EP 129 DI 10.1109/RELPHY.2002.996623 PG 8 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BU45H UT WOS:000176016400019 ER PT B AU Sexton, FW Dodd, PE Shaneyfelt, MR Schwank, JR AF Sexton, FW Dodd, PE Shaneyfelt, MR Schwank, JR GP IEEE IEEE IEEE IEEE TI Effects of e-beam mail sanitizing process on commercial electronics SO 40TH ANNUAL PROCEEDINGS: INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM SE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM LA English DT Meeting Abstract CT 40th Annual IEEE International Reliability Physics Symposium CY APR 07-11, 2002 CL DALLAS, TX SP IEEE Electron Devices Soc, IEEE Reliabil Soc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sexton, FW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7352-9 J9 INT REL PHY PY 2002 BP 376 EP 376 DI 10.1109/RELPHY.2002.996664 PG 1 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BU45H UT WOS:000176016400060 ER PT B AU Dabestani, R Ivanov, IN Sands, JM AF Dabestani, R Ivanov, IN Sands, JM BE Rasmussen, BM Pilato, LA Kliger, HS TI Application of time-resolved pulse radiolysis technique in the investigation of the mechanism of epoxy resins cationic polymerization SO 47TH INTERNATIONAL SAMPE SYMPOSIUM AND EXHIBITION, VOL 47, BOOKS 1 AND 2: AFFORDABLE MATERIALS TECHNOLOGY-PLATFORM TO GLOBAL VALUE AND PERFORMANCE LA English DT Proceedings Paper CT 47th International SAMPE Symposium and Exhibition CY MAY 12-16, 2002 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE electron beam; pulse radiolysis; transients; electron paramagnetic resonance ID TRIFLUORIDE-AMINE COMPLEXES; ELECTRON; UV AB E-beam induced cationic polymerization of epoxy resins is of great interest to industry because it offers many advantages over thermal curing methods. Despite good thermal properties epoxy-based composites prepared using E-beam curable resins exhibit low compression strength, poor interlaminar shear strength, and low fracture toughness. We have initiated a comprehensive study to investigate the mechanism of cationic polymerization of epoxy resins in an attempt to identify the factors that are responsible for these shortcomings associated with E-beam curable resins. The objective of this investigation is to use pulse radiolysis technique as a tool to identify the reactive intermediates involved in the polymerization process. We have employed pulse radiolysis in conjunction with optical detection and Electron Paramagnetic Resonance (EPR) spectroscopy to elucidate spectral features and the identity of reactive intermediates produced during the cationic polymerization of epoxy resins. The ultimate goal of this study is to identify the parameters that give rise to improved thermal and mechanical properties of the final composite prepared by electron beam curing. C1 Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Dabestani, R (reprint author), Oak Ridge Natl Lab, Div Chem Sci, POB 2008, Oak Ridge, TN 37831 USA. RI ivanov, ilia/D-3402-2015 OI ivanov, ilia/0000-0002-6726-2502 NR 19 TC 1 Z9 1 U1 0 U2 1 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA BN 0-938994-92-1 PY 2002 BP 51 EP 64 PG 14 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites SC Materials Science GA BU92A UT WOS:000177401800006 ER PT B AU Frame, BJ Wrenn, GE Janke, CJ AF Frame, BJ Wrenn, GE Janke, CJ BE Rasmussen, BM Pilato, LA Kliger, HS TI Results of electron beam prepreg debulking study SO 47TH INTERNATIONAL SAMPE SYMPOSIUM AND EXHIBITION, VOL 47, BOOKS 1 AND 2: AFFORDABLE MATERIALS TECHNOLOGY-PLATFORM TO GLOBAL VALUE AND PERFORMANCE LA English DT Proceedings Paper CT 47th International SAMPE Symposium and Exhibition CY MAY 12-16, 2002 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE electron beam curing; hand lay-up; laminates AB Electron beam curing of composites is a non-autoclave process, and consolidation pressure during cure has therefore been limited to that which may be provided by vacuum bagging the part, or by the application of direct mechanical force. Tooling to apply mechanical force tends to be limited to simple geometric shapes and may also block (shadow) the electron beam's path to the composite. Vacuum bagging is readily adapted to most complex three-dimensional parts but the applied consolidation is limited to roughly atmospheric pressure and therefore cannot be relied on to collapse the expansion of volatiles during cure of the electron beam cured laminate. Preventive measures are therefore needed to reduce the factors that cause voids. A critical opportunity to reduce voids in the cured laminate is to minimize air entrapment between plies during lay-up, This paper reports the results of process trials conducted with IM7-GP-12K/3K and IM7-GP-12K/8HM unidirectional prepreg tapes to evaluate vacuum debulking and other parameters on the reduction of voids in electron beam cured laminates. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Frame, BJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Janke, Christopher/E-1598-2017 OI Janke, Christopher/0000-0002-6076-7188 NR 6 TC 0 Z9 0 U1 0 U2 0 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA BN 0-938994-92-1 PY 2002 BP 65 EP 77 PG 13 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites SC Materials Science GA BU92A UT WOS:000177401800007 ER PT B AU Frame, BJ Hansen, JGR AF Frame, BJ Hansen, JGR BE Rasmussen, BM Pilato, LA Kliger, HS TI Fire resistant composite materials for energy absorption applications SO 47TH INTERNATIONAL SAMPE SYMPOSIUM AND EXHIBITION, VOL 47, BOOKS 1 AND 2: AFFORDABLE MATERIALS TECHNOLOGY-PLATFORM TO GLOBAL VALUE AND PERFORMANCE LA English DT Proceedings Paper CT 47th International SAMPE Symposium and Exhibition CY MAY 12-16, 2002 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE energy absorption; fire resistance; organic fiber AB Oak Ridge National Laboratory is evaluating lightweight composite materials for use in ballistic and blast mitigation applications. Processing of advanced composite materials has been developed to combine energy absorbing fibers with fire resistant resin matrices. The most promising combinations include Zylon poly(p-phenylene-2,6-berizobisoxazole) (PBO) fiber in phenolic-based and cyanate ester resins. These composite materials are being evaluated in fire and smoke tests to demonstrate their ability to meet government agency fire testing requirements. The composites are also evaluated using a ballistic screening test to determine the material's ability to absorb mechanical energy at high strain rate. A summary of the processing experience, fire test and ballistic test results to-date is presented. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Frame, BJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA BN 0-938994-92-1 PY 2002 BP 542 EP 555 PG 14 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites SC Materials Science GA BU92A UT WOS:000177401800048 ER PT B AU Chaiko, DJ AF Chaiko, DJ BE Rasmussen, BM Pilato, LA Kliger, HS TI The colloid chemistry of organoclays SO 47TH INTERNATIONAL SAMPE SYMPOSIUM AND EXHIBITION, VOL 47, BOOKS 1 AND 2: AFFORDABLE MATERIALS TECHNOLOGY-PLATFORM TO GLOBAL VALUE AND PERFORMANCE LA English DT Proceedings Paper CT 47th International SAMPE Symposium and Exhibition CY MAY 12-16, 2002 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE layered clay; nanocomposites; elastorriers/rubber ID NANOCOMPOSITES AB The delamination and dispersion of organoclays in hydrophobic polymeric systems involves a complex balancing of surface chemical interactions between the basal and edge surfaces of the organoclay and the polymer matrix, The proper design of surfactant coatings used to make organoclays remains a critical technical/economic obstacle to the commercial production of engineered plastics for high volume applications. At a minimum, modification of the clay surface is needed to satisfy wetting requirements, but the literature is replete with examples showing that surface wetting alone is insufficient to ensure exfoliation. This difficulty has led to the use of oligomeric compatibilizers but this approach is both expensive and inefficient. The thermodynamic factors which effect organoclay swelling and dispersion will be discussed and a basis for the design of self-dispersing organoclays will be presented. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Chaiko, DJ (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA BN 0-938994-92-1 PY 2002 BP 1064 EP 1073 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Materials Science, Composites SC Materials Science GA BU92A UT WOS:000177401800092 ER PT B AU Raybourn, EM Davies, J Kings, NJ AF Raybourn, EM Davies, J Kings, NJ BE Callaos, N HernandezEncinas, L Yetim, F TI Future directions in supporting virtual communities of practice: Designing tacit culture in adaptive collaborative knowledge sharing environments SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL I, PROCEEDINGS: INFORMATION SYSTEMS DEVELOPMENT I LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE culture; design; collaborative knowledge sharing; virtual communities of practice; intelligent software agents; WWW; computer-mediated communication AB Jasper II and Contact Space constitute a WWW-based knowledge sharing environment comprised of a system of intelligent software agents that support explicit and tacit knowledge sharing. Jasper II agents adaptively learn their user's interests by observing the user's behavior, while Contact Space agents dynamically move avatars to designated locations in a virtual space in order to support real time communication. In this paper we describe how this system facilitates and encourages the sharing of informal information by encouraging people to interact asynchronously and in real time where there are mutual concerns or interests. We present design scenarios for incorporating cultural and organizational cues into the knowledge sharing environment in order to offer enhanced support for communication among remote, mobile workers. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Raybourn, EM (reprint author), Sandia Natl Labs, POB 5800,MS 0839, Albuquerque, NM 87185 USA. NR 11 TC 0 Z9 0 U1 0 U2 2 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 408 EP 413 PG 6 WC Computer Science, Information Systems; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV42E UT WOS:000178906800074 ER PT B AU Hoza, M Bower, JC Stoops, LR Downing, TR Carter, RJ Millard, WD AF Hoza, M Bower, JC Stoops, LR Downing, TR Carter, RJ Millard, WD BE Callaos, N Leng, T Sanchez, B TI Architecture for a generalized emergency management software system SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL V, PROCEEDINGS: COMPUTER SCI I LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE architecture; component; emergency management; hazard analysis; models; object-oriented AB The Federal Emergency Management Information System (FEMIS) was originally developed by Pacific Northwest National Laboratory (PNNL) for the Chemical Stockpile Emergency Preparedness Program (CSEPP). It has evolved from a CSEPP-specific emergency management software system to a general-purpose system that supports multiple types of hazards. The latest step in the evolution is the adoption of a hazard analysis architecture that enables the incorporation of hazard models for each of the hazards such that the model is seamlessly incorporated into the FEMIS hazard analysis subsystem. This paper describes that new architecture. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Hoza, M (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, 902 Battelle Blvd, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 287 EP 290 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV59D UT WOS:000179459500052 ER PT B AU Luethke, B Scott, SL AF Luethke, B Scott, SL BE Callaos, N Leng, T Sanchez, B TI C3 power tools SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL V, PROCEEDINGS: COMPUTER SCI I LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE cluster; administration; federated-cluster; multi-cluster AB Through the administration and use of eXtremeTORC, HighTORC, TORC and the various other HPC clusters at Oak Ridge National Laboratory (ORNL), it quickly became apparent that a solution for the administration of federated clusters, or "clusters of clusters," was needed. While a few cluster tools did exist when this work was started, there were none with the vision to handle multiple clusters as a single cohesive computing enviromment. These other tools also required that the administrator or user be directly logged into a user account on one of the clustered machines. This resulted in at least one duplicate operation for each cluster being addressed. It is obvious that this process does not scale. Thus a solution was needed whereby an administrator or general HPC user could perform duplicate operations across multiple clusters, and portions thereof, in a scalable and secure fashion from a single location not necessarily one where the user is logged in. Thus was the drive for the development of version 3.0 of the Cluster Command and Control (3.0) power tools. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37830 USA. RP Luethke, B (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37830 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 382 EP 387 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV59D UT WOS:000179459500069 ER PT B AU Naughton, T Scott, SL Barrett, B Squyres, J Lumsdaine, A Fang, YC AF Naughton, T Scott, SL Barrett, B Squyres, J Lumsdaine, A Fang, YC BE Callaos, N Leng, T Sanchez, B TI The penguin in the pail - OSCAR cluster installation tool SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL V, PROCEEDINGS: COMPUTER SCI I LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada AB The Open Source Cluster Application Resources (OSCAR) project grew from the need for cluster tools to build, configure and manage the pile-of-PC clusters, which axe continuing to grow in popularity. The current "best cluster practices" axe leveraged to enable users to install and configure a working cluster in a timely fashion. The current release offers a number of popular tools, as well as improvements to the installation process for a cluster. As OSCAR has evolved, new research and development has been explored to extend the current practices. This paper discusses the status of the OSCAR project and its goals and objectives. The current development is discussed as OSCAR heads toward a newly designed OSCAR 2.0 infrastructure. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Naughton, T (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 388 EP 392 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV59D UT WOS:000179459500070 ER PT B AU Hathorn, BC Sumpter, BG Noid, DW AF Hathorn, BC Sumpter, BG Noid, DW BE Callaos, N Hammoud, R Xia, D Li, HS Klovsky, D TI Simulation of soft nanoparticles with hard surfaces. SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL XIV, PROCEEDINGS: IMAGE, ACOUSTIC, SPEECH AND SIGNAL PROCESSING III LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada ID MOLECULAR-DYNAMICS SIMULATIONS; COMPUTER AB Using recently developed techniques for large scale polymer nanoparticle simulations, the interactions of polymer nanoparticles; with graphite sheets is studied. The simulations are meant to describe newly evolving techniques for experimental construction and manipulation of nanoparticles in a variety of environments. The particles are comprised of flexible polymer chains-"soft matter" and undergo significant deformations during the course of the simulations, whereas the graphite sheet is composed of a rigid atomic structure. The molecular dynamics simulation incorporating a rigid surface greatly diminishes the computation time while retaining many of the fundamental physical properties of the system. Evolution of the particle is followed under a variety of conditions, in particular under rolling and sliding. Rolling conditions consist of particles with an initial angular velocity which are in contact with the fixed graphite surface and sliding particles consist of particles with an initial component of linear momentum parallel to the surface. During the course of the simulation it is observed that there is a ready transfer of energy to the surface. Such a transfer is expected to do the effective infinite mass of the surface atoms. A number of characteristic physical deformations are observed during the course of the simulations. The minimization of the potential energy is accomplished by minimizing the exposed surface area of the particles. The particles tend to reconfigure to a flattened configuration on the surface. The mechanisms for the reconfiguration are slightly different, however, with sliding particles deforming to accommodate the surface, while rolling particles are observed to "unpeel" with the particle losing local integrity and the exterior chains becoming affixed to the surface. C1 Oak Ridge Natl Lab, Div Comp Sci & Math, Oak Ridge, TN 37831 USA. RP Hathorn, BC (reprint author), Oak Ridge Natl Lab, Div Comp Sci & Math, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 13 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 40 EP 44 PG 5 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV42B UT WOS:000178906400008 ER PT B AU Hathorn, BC Sumpter, BG Noid, DW Barnes, MD AF Hathorn, BC Sumpter, BG Noid, DW Barnes, MD BE Callaos, N Hammoud, R Xia, D Li, HS Klovsky, D TI Vibrational normal modes of polymer nanoparticle systems using the time averaged normal coordinate analysis method. SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL XIV, PROCEEDINGS: IMAGE, ACOUSTIC, SPEECH AND SIGNAL PROCESSING III LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada ID MOLECULAR MECHANICS CALCULATIONS; MACROMOLECULAR SYSTEMS; DYNAMICS SIMULATIONS; PARTICLES; CRYSTALS AB In recent experiments using a nano-droplet method pioneered at Oak Ridge National Laboratory, it has been demonstrated that well-defined structures can be constructed from individual polymer nanoparticles. These structures are persistent for long timescales and are currently being investigated for their useful material properties. In an attempt to understand properties of these structures on a theoretical basis, simulated nanoparticle dimers have been generated by coupling two independent polymer nanoparticles. Similar to the experimental systems, the simulated particles show stability with respect to particle agglomeration due to decreased mobility of the individual monomer units caused by the extensive linkage in the polymer chains. The time averaged normal coordinate analysis method is employed to investigate the normal modes of the polymer nanoparticle dimers. In addition to providing accurate calculations of vibrational frequencies and vibrational displacements in dimerized nanoparticles, calculations have found classes of normal modes which are apparent in a wide variety of nanoparticle structures. While an approximate "dimer vibration" mode is evident, it appears to be strongly coupled to internal particle elasticity of the particles. Characteristic vibrations which correspond to coupled particle rotations appear to be substantially independent of much of the internal elasticity of the particles. We also observe large numbers of so-called spectator modes in which most of the vibrational motion is constrained to one of the particles in the dimer system. C1 Oak Ridge Natl Lab, Div Comp Sci & Math, Oak Ridge, TN 37831 USA. RP Hathorn, BC (reprint author), Oak Ridge Natl Lab, Div Comp Sci & Math, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 21 TC 0 Z9 0 U1 0 U2 1 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 45 EP 52 PG 8 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV42B UT WOS:000178906400009 ER PT B AU D'Antonio, PE AF D'Antonio, PE BE Callaos, N Ebisuzaki, T Starr, B Abe, JM Lichtblau, D TI A risk-based approach to reducing systems accidents SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL XVI, PROCEEDINGS: COMPUTER SCIENCE III LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE system safety; air transportation safety; accidents; risk; high consequence; red thinking; blue thinking AB This paper describes a risk-based strategy for meeting the challenge of reducing system accident rates using air transportation as an example, with particular emphasis on the oversight role. The strategy is based on decades of systems engineering progress in assuring the safety, security and reliability of the U.S. nuclear weapons stockpile. The strategy initially introduces basic system safety techniques into a reduced set of complementary modeling approaches that represent a portion of the system under consideration. Over time, the strategy is to gradually expand the scope to include additional elements of the system. As the scope expands, new hazards are introduced and addressed, new interactions are defined, and new system behaviors described. This paper describes how complementary models and analysis, based on a unique concept called Red and Blue Thinking, can facilitate the development of an improved risk management system that would enhance the ability to both assess system compliance with existing regulations and identify additional prioritized improvement opportunities that have the potential for reducing accident rates. A Red-Blue Thinking approach integrated into a top-down to bottoms-up decision-making process also assures that positive strides to continually improve system safety can be made while minimizing the risk that remedial measures may actually degrade safety. The strategy offers greater flexibility, improved defensibility, and improved understanding of the system risks, thus enabling a cost-effective systemic approach to reducing system accident rates. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP D'Antonio, PE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 179 EP 185 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BV62L UT WOS:000179558300033 ER PT B AU Raufeisen, J AF Raufeisen, J BE Callaos, N He, Y PerezPeraza, JA TI QCD coherence effects in high energy reactions with nuclei SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL XVII, PROCEEDINGS: INDUSTRIAL SYSTEMS AND ENGINEERING III LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE deep inelastic scattering; Drell-Yan process; QCD; nuclear effects; coherence effects; multiple scattering ID DEEP-INELASTIC SCATTERING; DRELL-YAN PROCESS; DIFFRACTION; DEPENDENCE; SATURATION; Q(2); DIS AB We investigate QCD coherence effects in deep inelastic scattering (DIS) off nuclei and in Drell-Yan (DY) dilepton production in proton-nucleus collisions within the light-cone color-dipole approach. The physical mechanisms underlying the nuclear effects become very transparent in this approach and are explained in some detail. We present numerical calculations of nuclear shadowing in DIS and DY and compare to data. Nuclear effects in the DY transverse momentum distribution are calculated as well. The dipole approach is the only known way to calculate the Cronin effect without introducing additional parameters for nuclear targets. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Raufeisen, J (reprint author), Los Alamos Natl Lab, MS H846, Los Alamos, NM 87545 USA. NR 33 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 95 EP 100 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Industrial SC Automation & Control Systems; Computer Science; Engineering GA BV43N UT WOS:000178929300017 ER PT B AU Cooper, JA AF Cooper, JA BE Callaos, N Zhao, R Sanchez, B Lesso, W TI A risk management decision analysis approach SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL XVIII, PROCEEDINGS: INFORMATION SYSTEMS, CONCEPTS AND APPLICATIONS OF SYSTEMICS, CYBERNETICS AND INFORMATICS LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE safety; risk; decisions; latent effects; trends; lessons learned AB Modem critical operation systems have grown in complexity, leading to a need for effective risk management decision tools. Such tools can help rank alternatives, assist in allocating resources, and can be used for defensible certification of critical operations. Existing methods are generally inefficient in accommodating changing environments and personnel threats. They are generally not intended to handle hard-to-quantify, subjective data, and most do not realistically estimate uncertainty. In this paper we discuss a mathematically structured approach that utilizes latent effects modeling and a strategic decomposition and aggregation approach to address these weaknesses. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cooper, JA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 19 EP 23 PG 5 WC Computer Science, Information Systems; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV43K UT WOS:000178929000004 ER PT B AU Burke, JS Danielson, GR Schulz, DA Vail, LW AF Burke, JS Danielson, GR Schulz, DA Vail, LW BE Callaos, N Zhao, R Sanchez, B Lesso, W TI Parallel computing for automated model calibration SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL XVIII, PROCEEDINGS: INFORMATION SYSTEMS, CONCEPTS AND APPLICATIONS OF SYSTEMICS, CYBERNETICS AND INFORMATICS LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE model calibration; distributed computing; null-cycle computing AB The calibration of computational models places a significant burden on computing and staff resources. Most assessments must consider multiple calibration objectives (e.g., magnitude and timing of stream flow peak). An automated model calibration process is needed that enables real-time updating of data/models, allowing scientists to focus their efforts on model improvements, not calibration details. Pacific Northwest National Laboratory (PNNL) is building a multi-objective calibration tool capable of efficiently processing multiple models using null-cycle computing. We have developed a generic parallel processing and calibration architecture, though our current focus has been on demonstrating its use for calibration of natural resources models. Our current results show these models to be friendly to parallel calibration efforts because they require no inter-process communication, need only a small amount of input data, and output only a small amount of statistical information for each calibration run. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Battelle Mem Inst, Pacific NW Natl Labs, 902 Battelle Blvd, Richland, WA 99352 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 424 EP 429 PG 6 WC Computer Science, Information Systems; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV43K UT WOS:000178929000077 ER PT B AU Millard, WD Carter, RJ AF Millard, WD Carter, RJ BE Callaos, N Zhao, R Sanchez, B Lesso, W TI Information sharing challenges for large multi-jurisdiction issues SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL XVIII, PROCEEDINGS: INFORMATION SYSTEMS, CONCEPTS AND APPLICATIONS OF SYSTEMICS, CYBERNETICS AND INFORMATICS LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE emergency management; multi-jurisdiction; decision support; information sharing; distributed databases; policy; and decision making AB Decision makers and scientists are becoming moremore aware that the major issues facing our society are very complex and often intricately interwoven. Large multi-jurisdictional problems are very difficult to solve. It is no longer appropriate for a single group to have unilateral control over making a decision. Rather, decision-making has become a collaborative process where multiple representatives must balance the needs of multiple issues across multiple jurisdictions to reach a consensus. In order for decision-makers to effectively handle the complexity of these issues, automation tools must be provided that can operate effectively in a multi-jurisdictional environment. Decision support systems that span multiple users, agencies, and jurisdictions should provide users with the information needed to make decisions and the ability to disseminate those decisions. To do so, such systems need the capability to control the ownership of information control how information is shared dynamic geographic information from multiple jurisdictions disseminate dynamic status information between jurisdictions notify appropriate users across jurisdictions of changes to decisions and information. The Pacific Northwest National Laboratory (PNNL) has developed a multi-jurisdiction decision support architecture that provides an answer to each of these automation challenges. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Millard, WD (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 449 EP 454 PG 6 WC Computer Science, Information Systems; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV43K UT WOS:000178929000081 ER PT B AU Thurman, DA Peterson, TS Frodge, J AF Thurman, DA Peterson, TS Frodge, J BE Callaos, N Zhao, R Sanchez, B Lesso, W TI Defining requirements for an integrated water resource modeling system SO 6TH WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL XVIII, PROCEEDINGS: INFORMATION SYSTEMS, CONCEPTS AND APPLICATIONS OF SYSTEMICS, CYBERNETICS AND INFORMATICS LA English DT Proceedings Paper CT 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002)/8th International Conference on Information Systems Analysis and Synthesis (ISAS 2002) CY JUL 14-18, 2002 CL ORLANDO, FL SP Int Inst Informat & System, World Org System & Cybernet, Ctr Syst Studies, Syst Soc Poland, Soc Appl Syst Res, Slovenian Artificial Intelligence Soc, Simon Bolivar Univ, Polish Syst Soc, Italian Soc System, Int Soc Syst Sci, Int Syst Inst, Int Federat Syst Res, Cybernet & Human Knowing, Journal Second Order Cybernet & Cybersemiot, Blaise Pascal Univ, Engineer Sci Inst, CUST, Univ Las Palmas Gran Canaria, Concurrency & Architecture Grp, Telemat Engn Dept, Tunisian Sci Soc, Acad Non Linear Sci, San Luis Natl Univ, Lab Res Computat Intelligence, Dept Informat, Amer Soc Cybernet (Canada), Wolfram Res Inc, IEEE Comp Soc, Venezuela Chapter, Steacie Inst Molec Sci, Natl Res Council Canada DE requirements analysis; system design; integrated modeling AB This paper describes the process used to define requirements for an integrated water resource modeling capability useful to users with varying backgrounds and needs. The project team completed a five-step process to take into account the needs and interests of users representing many different parts of a natural resource management agency. This paper presents steps of the process, the results of each step, and a summary of results. C1 Pacific NW Natl Lab, Seattle, WA 98105 USA. RP Thurman, DA (reprint author), Pacific NW Natl Lab, Seattle, WA 98105 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU INT INST INFORMATICS & SYSTEMICS PI ORLANDO PA 14269 LORD BARCLAY DR, ORLANDO, FL 32837 USA PY 2002 BP 474 EP 479 PG 6 WC Computer Science, Information Systems; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV43K UT WOS:000178929000086 ER PT B AU Talou, P Chadwick, MB Young, PG AF Talou, P Chadwick, MB Young, PG BE Herman, M Paver, N Stanculescu, A TI Recent developments in nuclear data for ADS SO ACCELERATOR DRIVEN SYSTEMS FOR ENERGY PRODUCTION AND WASTE INCINERATION: PHYSICS, DESIGN AND RELATED NUCLEAR DATA SE ICTP LECTURE NOTES SERIES LA English DT Proceedings Paper CT Workshop on Hybrid Nuclear Systems for Energy Production, Utilisation of Actinides and Transmutation of Long-Lived Radioactive Waste/Workshop on Nuclear Data for Science and Technology CY SEP, 2001 CL Trieste, ITALY SP Abdus Salam Int Ctr Theoret Phys ID ACCELERATOR-DRIVEN SYSTEMS; CROSS-SECTIONS; ANGULAR-DISTRIBUTIONS; MULTISTEP COMPOUND; NEUTRON-PRODUCTION; PARTICLE SPECTRA; HIGH-RESOLUTION; PROTONS; ENERGIES; MODEL AB Modern particle accelerators offer new opportunities to dramatically reshape the way we think about nuclear energy, and challenge some of the thorniest problems linked to its industrial use, e.g. nuclear waste. A powerful proton accelerator driving a sub-critical fission reactor could be used for producing energy more safely and burning up the extra spent fuel which so far has been stored in geological repositories. Although large R&D efforts are required to successfully implement such Accelerator Driven Systems (ADS), an important theoretical effort is also required to extend the nuclear data libraries, originally developed for existing nuclear reactors needs. The energies and isotopes involved in ADS do not necessarily overlap the range covered by the current nuclear reactors, and therefore there is a strong and urgent need to review and complement the nuclear cross sections databases to efficiently and safely build these ADS. In this workshop, we will review some of the strength and deficiencies in the existing nuclear data libraries, for applications to ADS projects. A major step forward to extend these libraries has been achieved recently by the release of the LA150 cross section library [M.B. Chadwick et al., NSE 131, 293 (1999)], evaluating reactions cross sections for different materials important for ADS, up to 150 MeV incident energies. We will devote a rather large fraction of theses lectures to present the latest developments in LA150. We will also present various numerical simulations performed in order to test and benchmark this new data library. Such evaluations rely on nuclear reaction calculations performed with the GNASH code, and on available experimental data. We will therefore briefly review the physical models used in these calculations and present their importance in the GNASH code. Another part in developing accurate nuclear data library consists in the evaluation of available experimental data, as an attempt to significantly reduce the systematic uncertainties which always affect experimental results. We will present the Bayesian inference scheme as a powerful tool to achieve this goal, and will illustrate this concept with the example of the evaluation of Pu-239 (n,f), recently assessed in the context of the ATW/AAA(1) program in Los Alamos. C1 Los Alamos Natl Lab, Div Theoret, Nucl Phys Grp, Los Alamos, NM USA. RP Talou, P (reprint author), Los Alamos Natl Lab, Div Theoret, Nucl Phys Grp, T-16, Los Alamos, NM USA. NR 62 TC 0 Z9 0 U1 4 U2 5 PU INT CENTRE THEORETICAL PHYSICS PI TRIESTE PA POB 586, 34100 TRIESTE, ITALY BN 92-95003-17-9 J9 ICTP LECT NOTES PY 2002 VL 12 BP 419 EP 475 PG 57 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BY52Z UT WOS:000189401100010 ER PT J AU Wozniak, PR Udalski, A Szymanski, M Kubiak, M Pietrzynski, G Soszynski, I Zebrun, K AF Wozniak, PR Udalski, A Szymanski, M Kubiak, M Pietrzynski, G Soszynski, I Zebrun, K TI Difference image analysis of the OGLE-II bulge data. III. Catalog of 200 000 candidate variable stars SO ACTA ASTRONOMICA LA English DT Article DE Galaxy : center; Catalogs; Stars : variables : general ID GRAVITATIONAL LENSING EXPERIMENT; LARGE-MAGELLANIC-CLOUD; DENSE STELLAR REGIONS; MICROLENSING EVENTS; GALACTIC BULGE; BVI MAPS; PROJECT; SUBTRACTION; CEPHEIDS AB We present the first edition of a catalog of variable stars from OGLE-II Galactic bulge data covering 3 years: 1997-1999. Typically 200-3001 band data points are available in 49 fields between -11 and 11 degrees in galactic longitude, totaling roughly 11 square degrees in sky coverage. Photometry was obtained using the Difference Image Analysis (DIA) software and tied to the OGLE data base with the DOPHOT package. The present version of the catalog comprises 221 801 light curves. In this preliminary work the level of contamination by spurious detections is still about 10%. Parts of the catalog. have only crude calibration, insufficient for distance determinations. The next, fully calibrated, edition will include the data collected in year 2000. The data is accessible via FTP. Due to the data volume, we also distribute DAT tapes upon request. C1 Princeton Univ Observ, Princeton, NJ 08544 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Warsaw Observ, PL-00478 Warsaw, Poland. Univ Concepcion, Dept Fis, Concepcion, Chile. RP Wozniak, PR (reprint author), Princeton Univ Observ, Peyton Hall, Princeton, NJ 08544 USA. EM wozniak@lanl.gov; udalski@astrouw.edu.pl; msz@astrouw.edu.pl; mk@astrouw.edu.pl; pietrzyn@astrouw.edu.pl; soszynsk@astrouw.edu.pl; zebrun@astrouw.edu.pl NR 23 TC 76 Z9 76 U1 0 U2 2 PU COPERNICUS FOUNDATION POLISH ASTRONOMY PI WARSAW PA AL UJAZDOWSKIE 4, 00-478 WARSAW, POLAND SN 0001-5237 J9 ACTA ASTRONOM JI Acta Astron. PY 2002 VL 52 IS 2 BP 129 EP 142 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 577JE UT WOS:000177057100002 ER PT J AU Udalski, A Szymanski, M Kubiak, M Pietrzynski, G Soszynski, I Wozniak, P Zebrun, K Szewczyk, O Wyrzykowski, L AF Udalski, A Szymanski, M Kubiak, M Pietrzynski, G Soszynski, I Wozniak, P Zebrun, K Szewczyk, O Wyrzykowski, L TI The optical gravitational lensing experiment. BVI maps of dense stellar regions. III. The Galactic bulge SO ACTA ASTRONOMICA LA English DT Article DE Galaxy : bulge; surveys; catalogs; techniques : photometric ID LARGE-MAGELLANIC-CLOUD; PHOTOMETRY; EXTINCTION; CATALOG; STARS AB We present the VI photometric maps of the Galactic bulge. They contain VI photometry and astrometry of about 30 million stars from 49 fields of 0.225 square degree each in the Galactic center region. The data were collected during the second phase of the OGLE microlensing project. We discuss,the accuracy of data and present color-magnitude diagrams of selected fields observed by OGLE in the Galactic bulge. The VI maps of the Galactic bulge are accessible electronically for the astronomical community from the OGLE Internet archive. C1 Univ Warsaw Observ, PL-00478 Warsaw, Poland. Univ Concepcion, Dept Fis, Concepcion, Chile. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Udalski, A (reprint author), Univ Warsaw Observ, Al Ujazdowskie 4, PL-00478 Warsaw, Poland. EM udalski@astrouw.edu.pl; msz@astrouw.edu.pl; mk@astrouw.edu.pl; pietrzyn@astrouw.edu.pl; soszynsk@astrouw.edu.pl; wozniak@lanl.gov; zebrun@astrouw.edu.pl; szewczyk@astrouw.edu.pl; wyrzykow@astrouw.edu.pl NR 17 TC 83 Z9 83 U1 0 U2 1 PU COPERNICUS FOUNDATION POLISH ASTRONOMY PI WARSAW PA AL UJAZDOWSKIE 4, 00-478 WARSAW, POLAND SN 0001-5237 J9 ACTA ASTRONOM JI Acta Astron. PY 2002 VL 52 IS 3 BP 217 EP 240 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 603JR UT WOS:000178556300002 ER PT J AU Soszynski, I Udalski, A Szymanski, M Kubiak, M Pietrzynski, G Wozniak, P Zebrun, K Szewczyk, O Wyrzykowski, L AF Soszynski, I Udalski, A Szymanski, M Kubiak, M Pietrzynski, G Wozniak, P Zebrun, K Szewczyk, O Wyrzykowski, L TI The optical gravitational lensing experiment. Catalog of RR Lyr stars from the Small Magellanic Cloud SO ACTA ASTRONOMICA LA English DT Article DE stars : variables : RR Lyr Magellanic Clouds; catalogs ID DIFFERENCE IMAGE-ANALYSIS; GALACTIC GLOBULAR-CLUSTERS; MAIN-SEQUENCE TURNOFF; VARIABLE-STARS; CCD PHOTOMETRY; SMC DATA; LMC; SUBTRACTION; PROJECT; MAPS AB We present the catalog of RR Lyrae stars from 2.4 square degrees of central parts of the Small Magellanic Cloud (SMC). The photometric data were collected during four years of the OGLE-H microlensing survey. Photometry of each star was obtained using the Difference Image Analysis (DIA) method. The catalog contains 571 objects, including 458 RRab, 56 RRc variables, and 57 double mode RR Lyr stars (RRd). Additionally we attach a list of variables with periods between 0.18-0.26 days, which are probably delta Sct stars. Period, BVI photometry, astrometry, amplitude, and parameters of the Fourier decomposition of the I-band light curve are provided for each object. We also present the Petersen diagram for double mode pulsators. We found that the SMC RR Lyr stars are fairly uniformly distributed over the studied area, with no clear correlation to any location. The most preferred periods for RRab and RRc stars are 0.589 and 0.357 days, respectively. We noticed significant excess of stars with periods of about 0.29 days, which might be second-overtone RR Lyr stars (RRe). The mean extinction free magnitudes derived for RRab stars are 18.97, 19.45 and 19.73 mag for the 1, V and B-band, respectively. All presented data, including individual BVI observations, are available from the OGLE INTERNET archive. C1 Univ Warsaw Observ, PL-00478 Warsaw, Poland. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Concepcion, Dept Fis, Concepcion, Chile. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Soszynski, I (reprint author), Univ Warsaw Observ, Al Ujazdowskie 4, PL-00478 Warsaw, Poland. EM soszynsk@astrouw.edu.pl; udalski@astrouw.edu.pl; msz@astrouw.edu.pl; mk@astrouw.edu.pl; pietrzyn@astrouw.edu.pl; wozniak@lanl.gov; zebrun@astrouw.edu.pl; szewczyk@astrouw.edu.pl; wyrzykow@astrouw.edu.pl NR 38 TC 38 Z9 38 U1 0 U2 1 PU COPERNICUS FOUNDATION POLISH ASTRONOMY PI WARSAW PA AL UJAZDOWSKIE 4, 00-478 WARSAW, POLAND SN 0001-5237 J9 ACTA ASTRONOM JI Acta Astron. PY 2002 VL 52 IS 4 BP 369 EP 396 PG 28 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 636EY UT WOS:000180442700003 ER PT J AU Grosse-Kunstleve, RW Adams, PD AF Grosse-Kunstleve, RW Adams, PD TI Algorithms for deriving crystallographic spacegroup information. II. Treatment of special positions SO ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES LA English DT Article AB Algorithms for the treatment of special positions in three-dimensional crystallographic space groups are presented. These include an algorithm for the determination of the site-symmetry group given the coordinates of a point, an algorithm for the determination of the exact location of the nearest special position, an algorithm for the assignment of a Wyckoff letter given the site-symmetry group, and an alternative algorithm for the assignment of a Wyckoff letter given the coordinates of a point directly. All algorithms are implemented in ISO C++ and are integrated into the Computational Crystallography Toolbox. The source code is freely available. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Grosse-Kunstleve, RW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,Mail Stop 4-230, Berkeley, CA 94720 USA. EM rwgrosse-kunstleve@lbl.gov RI Adams, Paul/A-1977-2013 OI Adams, Paul/0000-0001-9333-8219 FU NIGMS NIH HHS [1P50 GM 62412] NR 12 TC 9 Z9 9 U1 0 U2 6 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 2053-2733 J9 ACTA CRYSTALLOGR A JI Acta Crystallogr. Sect. A PD JAN PY 2002 VL 58 BP 60 EP 65 DI 10.1107/S0108767301016658 PN 1 PG 6 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 505QJ UT WOS:000172926800010 PM 11752765 ER PT J AU Moon, RM Smith, HG AF Moon, RM Smith, HG TI Clifford Glenwood Shull 1915-2001 - Obituary SO ACTA CRYSTALLOGRAPHICA SECTION A LA English DT Biographical-Item C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Moon, RM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 0 TC 0 Z9 0 U1 0 U2 4 PU BLACKWELL MUNKSGAARD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7673 J9 ACTA CRYSTALLOGR A JI Acta Crystallogr. Sect. A PD JAN PY 2002 VL 58 BP 1 EP 3 PN 1 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 505QJ UT WOS:000172926800001 ER PT J AU Cobessi, D Huang, LS Ban, M Pon, NG Daldal, F Berry, EA AF Cobessi, D Huang, LS Ban, M Pon, NG Daldal, F Berry, EA TI The 2.6 angstrom resolution structure of Rhodobacter capsulatus bacterioferritin with metal-free dinuclear site and heme iron in a crystallographic 'special position' SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID ESCHERICHIA-COLI; PROGRAM AB Bacterioferritin from Rhodobacter capsulatus was crystallized and its structure was solved at 2.6 Angstrom resolution. This fit structure of a bacterioferritin from a photosynthetic organism is a spherical particle of 24 subunits displaying 432 point-group symmetry like ferritin and bacterioferritin from Escherichia coli. Crystallized in the I422 space group, its structural analysis reveals for the fit time the non-symmetric heme molecule located on a twofold crystallographic symmetry axis. Other hemes of the protomer are situated on twofold noncrystallographic axes. Apparently, both types of sites bind heme in two orientations, leading to an average structure consisting of a symmetric 50:50 mixture, thus satisfying the crystallographic and noncrystallographic symmetry of the crystal. Five water molecules are situated close to the heme, which is bound in a hydrophobic pocket and axially coordinated by two crystallographic or noncrystallographically related methionine residues. Its ferroxidase center, in which Fe-II is oxidized to Fe-III, is empty or fractionally occupied by a metal ion. Two positions are observed for the coordinating Glu18 side chain instead of one in the E. coli enzyme in which the site is occupied. This result suggests that the orientation of the Glu18 side chain could be constrained by this interaction. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Penn, Dept Biol, Inst Plant Sci, Philadelphia, PA 19104 USA. RP Berry, EA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NCRR NIH HHS [P41 RR001209]; NIDDK NIH HHS [DK44842, R01 DK044842]; NIGMS NIH HHS [GM62563, R01 GM038237, R01 GM062563] NR 20 TC 32 Z9 33 U1 0 U2 0 PU BLACKWELL MUNKSGAARD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD JAN PY 2002 VL 58 BP 29 EP 38 PN 1 PG 10 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 504JG UT WOS:000172853100004 PM 11752777 ER PT J AU Garcia, E Back, BB Baker, MD Barton, DS Betts, RR Bindel, R Budzanowski, A Busza, W Carroll, A Decowski, MP George, N Gulbrandsen, K Gushue, S Halliwell, C Heintzelman, GA Henderson, C Hofman, DJ Holynski, R Holzman, B Johnson, E Kane, JL Katzy, J Khan, N Kucewicz, W Kulinich, P Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, AC Mulmenstadt, J Nouicer, R Olszewski, A Pak, R Park, IC Pernegger, H Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Rosenberg, L Sarin, P Sawicki, P Skulski, W Steadman, SG Steinberg, P Stephans, GSF Stodulski, M Sukhanov, A Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B AF Garcia, E Back, BB Baker, MD Barton, DS Betts, RR Bindel, R Budzanowski, A Busza, W Carroll, A Decowski, MP George, N Gulbrandsen, K Gushue, S Halliwell, C Heintzelman, GA Henderson, C Hofman, DJ Holynski, R Holzman, B Johnson, E Kane, JL Katzy, J Khan, N Kucewicz, W Kulinich, P Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, AC Mulmenstadt, J Nouicer, R Olszewski, A Pak, R Park, IC Pernegger, H Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Rosenberg, L Sarin, P Sawicki, P Skulski, W Steadman, SG Steinberg, P Stephans, GSF Stodulski, M Sukhanov, A Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B CA PHOBOS Collaboration TI The PHOBOS experiment at RHIC SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 4th Latin American Symposium on Nuclear Physics CY SEP 24-28, 2001 CL COLEGIO NACL, MEXICO CITY, MEXICO HO COLEGIO NACL DE heavy-ion collisions; charged particle multiplicity; centrality dependence; antiparticle to particle ratio ID PLUS AU COLLISIONS; ROOT-S(NN)=130 GEV AB Since June 2000, the Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory has delivered the first collisions between Au nuclei at the highest center of mass energies achieved in the laboratory to date. PHOBOS is one of four experiments studying the Au+Au interactions at RHIC. In this paper we will describe the PHOBOS experiment, and discuss some of the current physics results obtained for Au+Au collisions at roots(NN) = 56 and 130 and 200 GeV. They include the study of the charged particle multiplicity as a function of pseudo-rapidity and centrality, and the measurements of the anti-particles to particles ratios. The observed charged particle densities near mid-rapidity are higher than previously measured in any nuclear collisions. Also the rate of increase of the mid-rapidity particle density with energy is faster than that for nucleon-nucleon collisions at comparable beam energies. Finally, the antiparticle to particle ratios indicate the creation of a nearly baryon free zone at mid-rapidity. C1 Univ Illinois, Chicago, IL 60607 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Inst Nucl Phys, Krakow, Poland. MIT, Cambridge, MA 02139 USA. Natl Cent Univ, Chungli 32054, Taiwan. Univ Maryland, College Pk, MD 20742 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Rochester, Rochester, NY 14627 USA. RP Garcia, E (reprint author), Univ Illinois, Chicago, IL 60607 USA. RI Decowski, Patrick/A-4341-2011; Mignerey, Alice/D-6623-2011; Muelmenstaedt, Johannes/K-2432-2015 OI Muelmenstaedt, Johannes/0000-0003-1105-6678 NR 9 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 16 IS 1-4 BP 153 EP 161 DI 10.1556/APH.16.2002.1-4.17 PG 9 WC Physics, Nuclear SC Physics GA 623QL UT WOS:000179714300017 ER PT J AU Randrup, J AF Randrup, J TI Correlated charged pions from chiral dynamics in high-energy nuclear collisions SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 4th Latin American Symposium on Nuclear Physics CY SEP 24-28, 2001 CL COLEGIO NACL, MEXICO CITY, MEXICO HO COLEGIO NACL DE relativistic heavy-ion collisions; chiral symmetry; pion production ID LINEAR SIGMA-MODEL; FIELD TREATMENT; CONDENSATE; DCC; SIMULATION AB It is expected that chiral symmetry is approximately restored in the very excited matter produced in a high-energy nuclear collision and that the chiral order parameter will thereafter quickly relax towards its aligned vacuum value. This non-equilibrium evolution of the environment endows the pionic degrees of freedom with a time-dependent effective mass and this agency, in turn, may create correlated soft pions that could provide specific observable signatures of the chiral dynamics that are based solely on charged pions. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. NR 16 TC 0 Z9 0 U1 0 U2 1 PU AKADEMIAI KIADO RT PI BUDAPEST PA PRIELLE K U 19, PO BOX 245,, H-1117 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 16 IS 1-4 BP 169 EP 180 DI 10.1556/APH.16.2002.1-4.19 PG 12 WC Physics, Nuclear SC Physics GA 623QL UT WOS:000179714300019 ER PT J AU McCormick, K AF McCormick, K CA Jefferson Lab Hall A Collaboration TI Few-body form factor measurements in Hall A of JLab SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 4th Latin American Symposium on Nuclear Physics CY SEP 24-28, 2001 CL COLEGIO NACL, MEXICO CITY, MEXICO HO COLEGIO NACL DE deuteron; helium 3; helium 4 ID ELECTRON-DEUTERON SCATTERING; HIGH MOMENTUM-TRANSFER; ELASTIC-SCATTERING; EQUATIONS AB There is an active program of few-body form factor measurements in Hall A of Thomas Jefferson National Accelerator Facility (Jefferson Laboratory). Recent measurements of the deuteron elastic electric, A(Q(2)), and magnetic, B(Q(2)), structure functions will be presented. Planned measurements of the form factors of He-3 and He-4 will also be discussed. C1 Kent State Univ, Kent, OH 44242 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP McCormick, K (reprint author), Kent State Univ, Kent, OH 44242 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 16 IS 1-4 BP 181 EP 186 DI 10.1556/APH.16.2002.1-4.20 PG 6 WC Physics, Nuclear SC Physics GA 623QL UT WOS:000179714300020 ER PT J AU Smith, ES AF Smith, ES TI Searching for gluonic excitations - The Hall D Project at JLab SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 4th Latin American Symposium on Nuclear Physics CY SEP 24-28, 2001 CL COLEGIO NACL, MEXICO CITY, MEXICO HO COLEGIO NACL DE gluonic excitations; hybrid mesons; coherent bremsstrahlung AB Hybrid mesons are produced when the gluonic degrees of freedom are excited within normal mesons. A large fraction of these gluonic excitations can be identified using unique combinations of spin, parity and charge conjugation (J(PC)) quantum numbers which are not allowed for ordinary q (q) over bar bound states. Photon beams are expected to be particularly favorable for the production of such states, which are required by the quark confining mechanism of QCD. Mapping out the spectrum and decay modes of these hybrid mesons is the necessary first step in understanding the nature of confinement. Plans are underway at Jefferson Lab to upgrade the energy of the electron accelerator to 12 GeV. With 12 GeV electrons, a 9 GeV linearly polarized photon beam will be produced using the coherent bremsstrahlung technique. Along with this energy upgrade, a hermetic detector housed in new experimental hall (Hall D) will be used to collect data on photoproduced mesons with unprecedented statistics. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Smith, ES (reprint author), Jefferson Lab, Newport News, VA 23606 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 16 IS 1-4 BP 187 EP 192 DI 10.1556/APH.16.2002.1-4.21 PG 6 WC Physics, Nuclear SC Physics GA 623QL UT WOS:000179714300021 ER PT J AU Liang, JF AF Liang, JF TI Study of nuclear reactions with radioactive F-17 at HRIBF SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 4th Latin American Symposium on Nuclear Physics CY SEP 24-28, 2001 CL COLEGIO NACL, MEXICO CITY, MEXICO HO COLEGIO NACL DE radioactive beams; resonance; breakup ID ION-BEAMS; RESONANT REACTIONS; COULOMB BARRIER; HALO NUCLEI; EMISSION; FUSION; SCATTERING; BREAKUP; NE-18 AB Radioactive F-17 beams were produced at the Holifield Radioactive Ion Beam Facility (HRIBF) using the Isotope Separator On-Line ISOL) technique. Two of the experiments using accelerated F-17 beams to study reaction mechanisms are presented: the simultaneous emission of two protons from a resonance in Ne-18 and the breakup of F-17 by Pb-208. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37830 USA. RP Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37830 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO RT PI BUDAPEST PA PRIELLE K U 19, PO BOX 245,, H-1117 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 16 IS 1-4 BP 213 EP 221 DI 10.1556/APH.16.2002.1-4.24 PG 9 WC Physics, Nuclear SC Physics GA 623QL UT WOS:000179714300024 ER PT J AU Amos, K Karataglidis, S AF Amos, K Karataglidis, S TI Predictions of a microscopic model of p-A scattering SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 4th Latin American Symposium on Nuclear Physics CY SEP 24-28, 2001 CL COLEGIO NACL, MEXICO CITY, MEXICO HO COLEGIO NACL DE optical potential; total reaction cross section; angular distributions ID REACTION CROSS-SECTIONS; NUCLEON-NUCLEUS SCATTERING; ENERGIES AB Proton scattering from nuclei can be predicted using optical potentials formed by full folding an effective two-nucleon interaction with detailed nuclear structure. Excellent results are found in comparison with measured total reaction as well as with measured differential cross sections. C1 Univ Melbourne, Sch Phys, Melbourne, Vic 3010, Australia. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Univ Melbourne, Sch Phys, Melbourne, Vic 3010, Australia. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO RT PI BUDAPEST PA PRIELLE K U 19, PO BOX 245,, H-1117 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 16 IS 1-4 BP 327 EP 336 DI 10.1556/APH.16.2002.1-4.35 PG 10 WC Physics, Nuclear SC Physics GA 623QL UT WOS:000179714300035 ER PT J AU Fachini, P AF Fachini, P CA STAR Collaboration TI Resonance studies at STAR SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE RHIC; resonance; particle production ID COLLISIONS; EXTRACTION AB Preliminary results from measurements of resonances (K*(0)(892), (K*(0)) over bar (892), Phi(1020), and rho(770)) and weakly decaying particles (Lambda(1116), (&ULambda;) over bar (1116), and K-S(0)(498)) are presented. The measurements are performed at mid-rapidity by the STAR detector in roots(NN) = 130 GeV Au-Au collisions at RHIC. The ratios K*(0)/h(-), (K*(0)) over bar and (&ULambda;) over bar/Lambda are compared to measurements at different energies and colliding systems. Estimates of thermal parameters, such as temperature and baryon chemical potential, are also presented. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Fachini, P (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 24 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 195 EP 204 DI 10.1556/APH.15.2002.3-4.3 PG 10 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200003 ER PT J AU Back, BB Baker, MD Barton, DS Betts, RR Bindel, R Budzanowski, A Busza, W Carroll, A Decowski, MP Garcia, E George, N Gulbrandsen, K Gushue, S Halliwell, C Heintzelman, GA Henderson, C Hofman, DJ Holynski, R Holzman, B Johnson, E Kane, JL Katzy, J Khan, N Kucewicz, W Kulinich, P Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, AC Mulmenstadt, J Nouicer, R Olszewski, A Pak, R Park, IC Pernegger, H Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Rosenberg, L Sarin, P Sawicki, P Skulski, W Steadman, SG Steinberg, P Stephans, GSF Stodulski, M Sukhanov, A Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B AF Back, BB Baker, MD Barton, DS Betts, RR Bindel, R Budzanowski, A Busza, W Carroll, A Decowski, MP Garcia, E George, N Gulbrandsen, K Gushue, S Halliwell, C Heintzelman, GA Henderson, C Hofman, DJ Holynski, R Holzman, B Johnson, E Kane, JL Katzy, J Khan, N Kucewicz, W Kulinich, P Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, AC Mulmenstadt, J Nouicer, R Olszewski, A Pak, R Park, IC Pernegger, H Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Rosenberg, L Sarin, P Sawicki, P Skulski, W Steadman, SG Steinberg, P Stephans, GSF Stodulski, M Sukhanov, A Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B CA PHOBOS Collaboration TI Results from the PHOBOS experiment at RHIC SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE relativistic heavy-ion collisions; charged particle multiplicity; elliptic flow; antiparticle-particle ratio ID PLUS AU COLLISIONS; NUCLEAR COLLISIONS AB Au+Au collisions have been studied at center-of-mass energies of roots(NN) = 56 and 130 GeV using the PHOBOS detector at RHIC. Charged particle multiplicities have been measured as a function of center-of-mass energy, centrality and pseudo-rapidity, eta. A total of 4100 +/- 400 charged particles are observed in the pseudo-rapidity range -5.4 < η < 5.4 for the most central collisions. A strong elliptic flow signal is seen in peripheral collisions at eta = 0. The measurement of an antiprotons to protons ratio of (p) over bar /p = 0.60 +/- 0.04(stat) +/- 0.06(syst) indicates that a nearly baryon-free region is created at midrapidity. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Inst Phys Nucl, Krakow, Poland. MIT, Cambridge, MA 02139 USA. Natl Cent Univ, Chungli, Taiwan. Univ Illinois, Chicago, IL 60607 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Rochester, Rochester, NY 14627 USA. RP Back, BB (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Decowski, Patrick/A-4341-2011; Mignerey, Alice/D-6623-2011; Muelmenstaedt, Johannes/K-2432-2015 OI Muelmenstaedt, Johannes/0000-0003-1105-6678 NR 12 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 225 EP 235 DI 10.1556/APH.15.2002.3-4.6 PG 11 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200006 ER PT J AU Johnson, I AF Johnson, I CA STAR Collaboration TI Photon production in Au plus Au collisions at root(NN)-N-S=130 GeV SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE heavy ion physics; photons; neutral pions ID QUARK-GLUON PLASMA; LEPTONS; PSIONS AB We report raw photon, neutral pion and eta measurements at RHIC. Photons in the energy range from 100MeV - 4GeV were detected by reconstructing e(+)e(-) pair production, gamma + Z --> e(+) + e(-) + Z, with the STAR Time Projection Chamber (TPC). Along with the photon detection technique we discuss the purity of the photon candidates and measurements of hadronic decays via their electromagnetic decay channels. The pi(0) --> gammagamma and eta --> gammagamma decay channels are addressed. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. RP Johnson, I (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Johnson, Ian/I-2439-2013 NR 7 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 247 EP 255 DI 10.1556/APH.15.2002.3-4.8 PG 9 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200008 ER PT J AU Videbaek, F AF Videbaek, F TI Stopping in relativistic heavy ion reactions - From SIS to RHIC SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE nuclear stopping; baryon distributions ID PLUS AU COLLISIONS; ROOT-S(NN)=130 GEV; AU+AU COLLISIONS; RAPIDITY; MIDRAPIDITY; RATIOS; FLOW AB The status of stopping in heavy ion reactions is reviewed by comparing available data in pp, pA and AA systems over the energy regime roots(NN) approximate to 2.5-130 GeV. The data consist of average rapidity losses, anti-proton over proton ratios, and net-baryon values at mid-rapidity. The overall features of nuclear stopping are reasonably well described by simple extrapolations of pp and pA collisions to AA. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Videbaek, F (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 30 TC 3 Z9 3 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 303 EP 313 DI 10.1556/APH.15.2002.3-4.13 PG 11 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200013 ER PT J AU Sanders, SJ Bearden, IG Beavis, D Besliu, C Blyakhman, Y Brzychczyk, J Budick, B Boggild, H Chasman, C Christensen, CH Christiansen, P Cibor, J Debbe, R Gaardhoje, JJ Grotowski, K Hagel, K Hansen, O Holm, A Holme, AK Ito, H Jakobsen, E Jipa, A Jordre, JI Jundt, F Jorgensen, CE Keutgen, T Kim, EJ Kozik, T Larsen, TM Lee, JH Lee, YK Lovhoiden, G Majka, Z Makeev, A McBreen, B Murray, M Natowitz, J Nielsen, BS Olchanski, K Olness, J Ouerdane, D Planeta, R Rami, F Rohrich, D Samset, BH Sheetz, RA Sosin, Z Staszel, P Thorsteinsen, TF Tveter, TS Videbaek, F Wada, R Wieloch, A Zgura, IS AF Sanders, SJ Bearden, IG Beavis, D Besliu, C Blyakhman, Y Brzychczyk, J Budick, B Boggild, H Chasman, C Christensen, CH Christiansen, P Cibor, J Debbe, R Gaardhoje, JJ Grotowski, K Hagel, K Hansen, O Holm, A Holme, AK Ito, H Jakobsen, E Jipa, A Jordre, JI Jundt, F Jorgensen, CE Keutgen, T Kim, EJ Kozik, T Larsen, TM Lee, JH Lee, YK Lovhoiden, G Majka, Z Makeev, A McBreen, B Murray, M Natowitz, J Nielsen, BS Olchanski, K Olness, J Ouerdane, D Planeta, R Rami, F Rohrich, D Samset, BH Sheetz, RA Sosin, Z Staszel, P Thorsteinsen, TF Tveter, TS Videbaek, F Wada, R Wieloch, A Zgura, IS CA BRAHMS Collaboration TI Charged particle multiplicities at BRAHMS SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE charged particle densities ID CENTRALITY DEPENDENCE; AU COLLISIONS; ENERGIES AB Charged particle pseudorapidity densities are presented for the Au-197 + Au-197 reaction at roots(NN) = 130 GeV. These densities provide an essential characterization of the underlying reactions mechanisms for ultra-relativistic heavy-ion collisions. This talk details how the global charged particle yields are measured at BRAHMS and presents some preliminary results from the analysis of data taken during the first year of the RHIC experimental program. C1 Univ Kansas, Lawrence, KS 66049 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Strasbourg 1, Strasbourg, France. Inst Rech Subatom, Strasbourg, France. Inst Nucl Phys, Krakow, Poland. Jagiellonian Univ, Krakow, Poland. Johns Hopkins Univ, Baltimore, MD 21218 USA. NYU, New York, NY 10003 USA. Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Texas A&M Univ, College Stn, TX 77843 USA. Univ Bergen, Dept Phys, Bergen, Norway. Univ Bucharest, Bucharest, Romania. Univ Oslo, Dept Phys, Oslo, Norway. RP Sanders, SJ (reprint author), Univ Kansas, Lawrence, KS 66049 USA. RI Bearden, Ian/M-4504-2014; Christensen, Christian Holm/A-4901-2010; Christensen, Christian/D-6461-2012; OI Bearden, Ian/0000-0003-2784-3094; Christensen, Christian Holm/0000-0002-1850-0121; Christensen, Christian/0000-0002-1850-0121; Gaardhoje, Jens-Jorgen/0000-0001-6122-4698 NR 11 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 315 EP 326 PG 12 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200014 ER PT J AU Norbeck, E Onel, Y Penzo, A White, S AF Norbeck, E Onel, Y Penzo, A White, S TI Polarized pp physics with internal jet targets at RHIC SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE gas jet target; polarized proton scattering; polarization measurements ID COULOMB-NUCLEAR INTERFERENCE; PROTON AB The physics scope of RHIC could be extended to include fixed target experiments by the addition of a gas jet target. Two applications stand out among many possibilities. RHIC is the first accelerator to provide polarized proton beams with energy above 30 GeV. Extensive studies of pp colliding beams are planned for RHIC, but these will not cover the energy range covered with a fixed target, where the scattering of polarized protons from protons has not been adequately studied. Another important application is the possible use of a hydrocarbon jet to obtain a rapid and precise measurement of the polarization of the RHIC proton beams. A gas jet target with associated recoil detectors, electronics, and vacuum pumps is available and can be installed with low incremental costs on a short time scale. C1 Univ Iowa, Iowa City, IA 52242 USA. Ist Nazl Fis Nucl, Trieste, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Norbeck, E (reprint author), Univ Iowa, Iowa City, IA 52242 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 327 EP 335 DI 10.1556/APH.15.2002.3-4.15 PG 9 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200015 ER PT J AU Bertulani, CA AF Bertulani, CA TI One- and two-photon physics with relativistic heavy ions SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE peripheral collisions; heavy ions ID POSITRON PAIR PRODUCTION; IMPACT-PARAMETER DEPENDENCE; COHERENT BREMSSTRAHLUNG; COULOMB DISSOCIATION; DIRAC-EQUATION; ELECTROMAGNETIC PRODUCTION; PERIPHERAL COLLISIONS; PARTICLE-PRODUCTION; ELECTRON-CAPTURE; CROSS-SECTION AB The physics of peripheral collisions with relativistic heavy ions (PCRHI) is reviewed. One- and two-photon processes are discussed. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Bertulani, CA (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 92 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 359 EP 368 DI 10.1556/APH.15.2002.3-4.18 PG 10 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200018 ER PT J AU Klein, S AF Klein, S CA STAR Collaboration TI Observation of Au+Au -> Au+Au+rho(0) and Au+Au -> Au*+Au*+rho(0) with STAR SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE relativistic heavy ions; vector mesons ID HEAVY-ION COLLISIONS; VECTOR-MESON PRODUCTION; PHYSICS AB We report the first observation of the reactions Au + Au --> Au + Au + rho(0) and Au + Au --> Au* + Au + rho(0) with the STAR detector. The rho are produced at small perpendicular momentum, as expected if they couple coherently to both nuclei. We discuss models of vector meson production and the correlation with nuclear breakup, and present a fundamental test of quantum mechanics that is possible with the system. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Klein, S (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 369 EP 379 DI 10.1556/APH.15.2002.3-4.19 PG 11 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200019 ER PT J AU Plasil, F AF Plasil, F CA ORLaND Project CoNDOR Collaboration TI ORLaND - Oak Ridge Laboratory for Neutrino Detectors SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE neutrinos; spallation AB The proposed Oak Ridge Laboratory for Neutrino Detectors (ORLaND), to be located adjacent to the Spallation Neutron Source (SNS), is described. ORLaND will take advantage of the fact that the SNS will be the world's best intermediate-energy pulsed neutrino source in the world. A broad range of neutrino measurements is contemplated by means of a number of detectors, including the large CoNDOR detector. Specifics of neutrino oscillation investigations, and of the possible impact of certain neutrino measurements on our understanding of supernova, explosions, are discussed. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Plasil, F (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 381 EP 390 DI 10.1556/APH.15.2002.3-4.20 PG 10 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200020 ER PT J AU Panitkin, SY AF Panitkin, SY TI Particle interferometry - Recent results from RHIC and SPS SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE heavy ion collisions; two-particle correlations ID HEAVY-ION COLLISIONS; PION INTERFEROMETRY AB We give an overview of the latest results of HBT studies in heavy ion collisions. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Panitkin, SY (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 26 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 401 EP 406 DI 10.1556/APH.15.2002.3-4.22 PG 6 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200022 ER PT J AU Verde, G Brown, DA Danielewicz, P Gelbke, CK Lynch, WG Tsang, MB AF Verde, G Brown, DA Danielewicz, P Gelbke, CK Lynch, WG Tsang, MB TI New approach to imaging of two-proton source functions SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 17th Winter Workshop on Nuclear Dynamics CY MAR 10-17, 2001 CL PARK CITY, UTAH DE two-proton correlation functions; imaging of emitting sources; heavy ion collision at intermediate energies ID SPACE-TIME EVOLUTION; HEAVY-ION REACTIONS; INTENSITY INTERFEROMETRY; COLLISIONS AB The influence of protons emitted from both fast and slow emission mechanisms in 2-proton correlations measured in heavy ion collisions at intermediate energies is discussed. The size of the fast emitting source is found to be determined mainly by the width of the correlation peak at 20 MeV/c, rather than by its magnitude. To illustrate the new analysis technique, the total momentum dependence of p-p correlations measured in N-14+(197) An reactions at E/A = 75 MeV is studied with an imaging analysis. The extracted results and the basic ideas behind the proposed analysis technique provide new tools for using particle-partcile correlation measurements as a probe of nuclear reactions. C1 Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Verde, G (reprint author), Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. RI Verde, Giuseppe/J-3609-2012; Lynch, William/I-1447-2013 OI Lynch, William/0000-0003-4503-176X NR 10 TC 0 Z9 0 U1 0 U2 1 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2002 VL 15 IS 3-4 BP 407 EP 416 DI 10.1556/APH.15.2002.3-4.23 PG 10 WC Physics, Nuclear SC Physics GA 563LM UT WOS:000176257200023 ER PT J AU Barrett, BR Navratil, P Ormand, WE Vary, JP AF Barrett, BR Navratil, P Ormand, WE Vary, JP TI Ab initio large-basis no-core shell model and its application to light nuclei SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 27th Mazurian Lakes School of Physics CY SEP 02-09, 2001 CL KRZYZE, POLAND SP Warsaw Univ, Andrzej Soltan Inst Nucl Studies ID CROSS-SECTIONS; ALPHA-PARTICLE; SYSTEMS; STATE AB We discuss the ab initio No-Core Shell Model (NCSM). In this method the effective Hamiltonians are derived microscopically from realistic nucleon-nucleon (NN) potentials, such as the CD-Bonn and the Argonne AV18 NN potentials, as a function of the finite Harmonic Oscillator (HO) basis space. We present converged results, i.e., up to 50hOhm? and 18hOhm HO excitations, respectively, for the A = 3 and 4 nucleon systems. Our results for these light systems are in agreement with results obtained by other exact methods. We also calculate properties of Li-6 and He-6 in model spaces up to 10hOhm? and of C-12 up to 6hOhm. Binding energies, rms radii, excitation spectra and electromagnetic properties are discussed. The favorable comparison with available data is a consequence of the underlying NN interaction rather than a phenomenological fit. C1 Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Barrett, BR (reprint author), Univ Arizona, Dept Phys, POB 210081, Tucson, AZ 85721 USA. NR 34 TC 11 Z9 11 U1 0 U2 1 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD JAN PY 2002 VL 33 IS 1 BP 297 EP 311 PG 15 WC Physics, Multidisciplinary SC Physics GA 527GX UT WOS:000174179300018 ER PT S AU Hogan, MJ Barnes, CD Clayton, CE O'Connell, C Decker, FJ Deng, S Emma, P Huang, C Iverson, R Johnson, DK Joshi, C Katsouleas, T Krejcik, P Lu, W Marsh, KA Mori, WB Muggli, P Siemann, RH Walz, D AF Hogan, MJ Barnes, CD Clayton, CE O'Connell, C Decker, FJ Deng, S Emma, P Huang, C Iverson, R Johnson, DK Joshi, C Katsouleas, T Krejcik, P Lu, W Marsh, KA Mori, WB Muggli, P Siemann, RH Walz, D BE Clayton, CE Muggli, P TI Acceleration and focusing of electrons and positrons using a 30 GeV drive beam SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID WAKEFIELD AB A series of plasma wakefield acceleration (PWFA) experiments are being conducted with a 30 GeV drive beam from the Stanford Linear Accelerator Center (SLAC). These experiments continue to address the application of meter-scale plasmas to focus and accelerate electrons and positrons in the context of future applications to high-energy accelerators. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Hogan, MJ (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RI Lu, Wei/F-2504-2016 NR 17 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 3 EP 10 PG 8 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300001 ER PT S AU Colby, ER AF Colby, ER BE Clayton, CE Muggli, P TI EM structure based and vacuum acceleration SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID COMB AB Physical and technical issues governing structure-based and vacuum acceleration of charged particles are reviewed, with emphasis on practical aspects. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Colby, ER (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd,MS 07, Menlo Pk, CA 94025 USA. NR 20 TC 3 Z9 3 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 39 EP 46 PG 8 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300004 ER PT S AU Conde, ME AF Conde, ME BE Clayton, CE Muggli, P TI Wakefield acceleration in structures SO ADVANCED ACCELERATOR CONCEPTS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB Wakefield acceleration in dielectric loaded structures is discussed in this paper. We present a description of the dielectric wakefield accelerator concept, comparing some features of the collinear and the two beam accelerator configurations. The Argonne Wakefield Accelerator Facility (AWA) is discussed in detail, including major upgrades that are presently taking place. The basic features and capabilities of the facility are presented, and the dielectric wakefield acceleration results are briefly summarized. Possible variants of the two beam accelerator configuration are discussed, and work on planar dielectric structures in various institutions is presented. We conclude this report mentioning prospective achievements of dielectric wakefield accelerating structures. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave,Bldg 362, Argonne, IL 60439 USA. EM conde@anl.gov NR 8 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 63 EP 70 PG 8 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300007 ER PT S AU Friedman, A AF Friedman, A BE Clayton, CE Muggli, P TI Overview of heavy ion fusion accelerator research in the US SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB This article provides an overview of current U.S. research on accelerators for Heavy Ion Fusion, that is, inertial fusion driven by intense beams of heavy ions with the goal of energy production. The concept, beam requirements, approach, and major issues are introduced. An overview of a number of new experiments is presented. These include: the High Current Experiment now underway at Lawrence Berkeley National Laboratory; studies of advanced injectors (and in particular an approach based on the merging of multiple beamlets), being investigated experimentally at Lawrence Livermore National Laboratory); the Neutralized (chamber) Transport Experiment being assembled at Lawrence Berkeley National Laboratory; and smaller experiments at the University of Maryland and at Princeton Plasma Physics Laboratory. The comprehensive program of beam simulations and theory is outlined. Finally, prospects and plans for further development of this promising approach to fusion energy are discussed. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Friedman, A (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 14 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 106 EP 117 PG 12 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300011 ER PT S AU Hogan, MJ Barov, N AF Hogan, MJ Barov, N BE Clayton, CE Muggli, P TI Summary report of working group 4: Electron Beam Driven Concepts SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB Although the title "Electron Beam Driven Concepts" can in principle cover a broad range of advanced accelerator schemes, in the context of this workshop and the various other working groups, working group 4 discussions centered primarily around the many active investigations of the electron or positron beam driven plasma wakefield accelerator. The past year has seen advances along three main fronts: experiment, simulation and theory. This paper will give a brief summary of the various talks presented to the group, summarize group discussions and conclude with a few comments on future directions. C1 Stanford Linear Accelerator Ctr, Accelerator Res Dept B, Menlo Pk, CA 94025 USA. RP Hogan, MJ (reprint author), Stanford Linear Accelerator Ctr, Accelerator Res Dept B, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. NR 0 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 147 EP 155 PG 9 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300015 ER PT S AU Power, JG Kimura, WD AF Power, JG Kimura, WD BE Clayton, CE Muggli, P TI Summary report on Working Group 5: Electromagnetic structure-based acceleration SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID ELECTRON AB Recent progress and new developments in Electromagnetic Structure-Based Acceleration were presented in this Working Group (WG). The presentations made to the WG were separated into two categories: slow-wave and fast-wave accelerating structures. The slow-wave talks included a theoretical study of accelerators at optical frequencies that showed there are important and surprising differences between optical structures and traditional microwave accelerators. Practical issues for dielectric loaded accelerators were also addressed including a novel method for frequency tuning of dielectric structures and, in a joint session with the mm-wave sources WG, dielectric high power test results were presented. Theory and simulation results were presented for both laser-driven and beam-driven (i.e., wakefield) novel structures including cylindrical and planar dielectric devices and photonic band gap (PBG) devices including a scheme to mimic a plasma channel with a PBG. In the fast-wave talks, progress in developing highly-tapered inverse free electron lasers (IFEL), staging IFELs for monoenergetic laser acceleration, and generating attosecond electron pulses were presented. New designs and applications of cyclotron-based devices driven by laser or RF energy were also discussed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Power, JG (reprint author), Argonne Natl Lab, 9700 S Cass Ave,Bldg 362, Argonne, IL 60439 USA. NR 15 TC 10 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 156 EP 164 PG 9 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300016 ER PT S AU Wang, XJ Kishek, R AF Wang, XJ Kishek, R BE Clayton, CE Muggli, P TI Beam generation, conditioning and monitoring: Working group VII report SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID FREE-ELECTRON-LASER; ACCELERATORS; INJECTION; PULSES AB The work presented at the working group VII: Beam Generation, Conditioning and Monitoring, is briefly summarized in this report. The challenges of the working group VII is to produce and preserve the high-brightness electron beam suitable for future second generation laser and other advanced accelerators. Topics presented in the working group covered wide range of subjects; facilities for high-intensity beam physics and X-ray generation, high-brightness femto-second beam generation, coherent transition radiation (CSR) and micro-bunch instability in the magnetic chicane bunch compressor, beam instrumentation for both transverse and longitudinal phase space characterization are the major topics discussed in the working group. C1 Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. RP Wang, XJ (reprint author), Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. NR 28 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 175 EP 183 PG 9 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300018 ER PT S AU Fubiani, G Dugan, G Leemans, W Esarey, E Bobin, JL AF Fubiani, G Dugan, G Leemans, W Esarey, E Bobin, JL BE Clayton, CE Muggli, P TI Semi-analytical 6D space charge model for dense electron bunches with large energy spreads SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID COLLIDING LASER-PULSES; ACCELERATION; WAKEFIELD; GENERATION AB Laser driven accelerators are capable of producing multi nC, multi MeV electron beams with transverse and longitudinal sizes on the order of microns. To investigate the transport of such electron bunches, a fast and fully relativistic space charge code which can handle beams with arbitrarily large energy spread has been developed. A 6-D macroparticle model for the beam is used to calculate the space charge fields at each time step. The collection of macroparticles is divided into longitudinal momentum bins, each with a small spread in relative momentum. The macroparticle distribution in each momentum bin is decomposed into ellipsoidal shells in position space. For each shell, an analytical expression for the electrostatic force in the bin rest frame is used. The total space charge force acting on one macroparticle in the lab frame is then the vector sum of the Lorentz-transformed forces from all the momentum bins. We have used this code to study the evolution of typical beams emerging from the plasma in the two most popular schemes, i.e., the self-modulated laser-wakefield-accelerator, where the laser pulse size is many times the plasma wavelength (L much greater than lambda(p)), and the colliding pulse laser-wakefield-accelerator regime where L similar to lambda(p) and two counterpropagationg laser pulses are used to inject electrons into the wakefield. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Fubiani, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. NR 15 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 203 EP 212 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300021 ER PT S AU Chen, YJ McCarrick, JF Guethlein, G Caporaso, GJ Chambers, F Falabella, S Lauer, E Richardson, R Sampayan, S Weir, J AF Chen, YJ McCarrick, JF Guethlein, G Caporaso, GJ Chambers, F Falabella, S Lauer, E Richardson, R Sampayan, S Weir, J BE Clayton, CE Muggli, P TI High intensity beam and x-ray converter target interactions and mitigation SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID ELECTRON-BEAM AB Ions extracted from a solid surface or plasma by impact of an high intensity and high current electron beam can partially neutralize the beam space charge and change the focusing system. We have investigated ion emission computationally and experimentally. By matching PIC simulation results with available experimental data, our finding suggests that if a mix of ion species is available at the emitting surface, protons dominate the backstreaming ion effects, and that, unless there is surface flashover, ion emission is source limited. We have also investigated mitigation, such as e-beam cleaning, laser cleaning and ion trapping with a foil barrier. The temporal behavior of beam spot size with a foil barrier and a focusing scheme to improve foil barrier performance are discussed. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Chen, YJ (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 17 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 240 EP 254 PG 15 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300026 ER PT S AU Barnes, CD Colby, ER Plettner, T AF Barnes, CD Colby, ER Plettner, T BE Clayton, CE Muggli, P TI LEAP phase II, net energy gain from laser fields in vacuum SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB The current Laser Electron Acceleration Program (LEAP) seeks to modulate the energy of an electron bunch by interaction of the electrons with a copropagating pair of crossed laser beams at 800 tun. We present an optical injector design for a LEAP cell so that it can be used to give net energy gain to an electron bunch. Unique features of the design are discussed which will allow this net energy gain and which will also provide a robust signature for the LEAP interaction. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Barnes, CD (reprint author), Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. NR 9 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 294 EP 299 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300032 ER PT S AU Cowan, B AF Cowan, B BE Clayton, CE Muggli, P TI Microfabrication of laser-driven accelerator structures SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB We discuss the potential for using microfabrication techniques for laser-driven accelerator construction. We introduce microfabrication processes in general, and then describe our investigation of a particular trial process. We conclude by considering the issues microfabrication raises for possible future structures. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Cowan, B (reprint author), Stanford Linear Accelerator Ctr, Mail Stop 7,2575 Sand Hill Rd, Menlo Pk, CA 94025 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 324 EP 330 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300035 ER PT S AU Liu, WM Gai, W AF Liu, WM Gai, W BE Clayton, CE Muggli, P TI Design of dielectric accelerator using TE-TM mode converter SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB A new design for X band dielectric accelerator using a TE-TM mode converter has been proposed and studied. It first converts RF from TE to TM mode in a pure metal section, then a tapered transition section is used for high efficiency transmission to the dielectric accelerator section. Because there is no dielectrics near the RF coupler, this scheme has potential to overcome RF breakdown problems near the coupling holes in the dielectric based accelerators, as it happened in the older designs. A detailed design study shows that high conversion efficiency (similar to100%) can be achieved for both single and dual coupling ports and it is less sensitive to machine errors than previous designs. Another advantage of this design is that it can be made to different modules thus greatly reduce the RD cycles. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Liu, WM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 469 EP 475 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300051 ER PT S AU Xiao, LL Jing, CU Gai, W Wong, T AF Xiao, LL Jing, CU Gai, W Wong, T BE Clayton, CE Muggli, P TI Wakefields in dielectric-loaded rectangular waveguide accelerating structures SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB Employing modal analysis, an accurate formulation to represent the electromagnetic wakefields generated by an electron charge bunch traveling along an off-center axis in a dielectric loaded rectangular waveguide accelerating structure is presented. The resulting x-dipole and y-dipole modes are described in detail. Specific analytical results were obtained for the dispersion characteristics, the transverse force, and the longitudinal wakefields. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Xiao, LL (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 542 EP 555 PG 14 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300057 ER PT S AU Power, JG Gai, W Jing, CG Konecny, R Gold, SH Kinkead, AK AF Power, JG Gai, W Jing, CG Konecny, R Gold, SH Kinkead, AK BE Clayton, CE Muggli, P TI High power testing of ANL X-band dielectric-loaded accelerating structures SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB A program is underway at Argonne National Laboratory to develop RF-driven dielectric-loaded accelerating (DLA) structures with the ultimate goal of demonstrating a compact, high-gradient linear accelerator based on this technology. In the first part of this program, as previously reported on, DLA structures were successfully designed, numerically modeled, constructed, vacuum tested, and cold tested with a network analyzer. In this paper, we report on the next stage of the program, the recent results of high power tests carried out on two DLA prototypes at the 11.424-GHz magnicon facility at the Naval Research Laboratory. The purpose of these tests was to study the DLA structure under high power conditions in order to look for signs of dielectric breakdown, a fundamental issue for this technology. In two separate series of experiments, the magnicon powered both a traveling-wave and standing-wave DLA structure. A discussion of results and future directions for this program will be presented. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Power, JG (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 TC 7 Z9 8 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 556 EP 564 PG 9 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300058 ER PT S AU Toth, C Faure, J van Tilborg, J Geddes, CGR Schroeder, CB Esarey, E Leemans, WP AF Toth, C Faure, J van Tilborg, J Geddes, CGR Schroeder, CB Esarey, E Leemans, WP BE Clayton, CE Muggli, P TI Shape-control of ultrashort laser pulses for optimal electron acceleration in plasmas SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID PHASE AB The temporal shape of 50-100 femtosecond Ti:sapphire laser pulses has been controlled by appropriate choice of the higher order spectral phase coefficients, and used for optimization of a plasma wake-field electron accelerator. C1 Lawrence Berkeley Lab, LOASIS Grp, Div Accelerator & Fus Res, Berkeley, CA 94720 USA. RP Toth, C (reprint author), Lawrence Berkeley Lab, LOASIS Grp, Div Accelerator & Fus Res, Bldg 71R0259,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 10 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 674 EP 680 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300070 ER PT S AU Faure, J Lefebvre, E Malka, V Marques, JR Amiranoff, F Solodov, A Mora, P AF Faure, J Lefebvre, E Malka, V Marques, JR Amiranoff, F Solodov, A Mora, P BE Clayton, CE Muggli, P TI Electron acceleration mechanisms in the interaction of ultrashort laser pulses with underdense plasmas: Experiments and simulations SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID TENUOUS PLASMAS; SCATTERING; CHANNELS; INTENSE; WAVES; BEAM AB An experiment investigating the production of relativistic electrons from the interaction of ultrashort multi-terawatt laser pulses with an underdense plasma is presented. Electrons were accelerated to tens of MeV and the maximum electron energy increased as the plasma density decreased. Simulations have been performed in order to model the experiment. They show a good agreement with the trends observed in the experiment and the spectra of accelerated electrons could be reproduced successfully. The simulations have been used to study the relative contribution of the different acceleration mechanisms: plasma wave acceleration, direct laser acceleration and stochastic heating. The results show that in the low density case (1% of the critical density), acceleration by plasma waves dominates whereas in the high density case (10% of the critical density) acceleration by the laser is the dominant mechanism. The simulations at high density also suggest that direct laser acceleration is more efficient than stochastic heating. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Ecole Polytech, Lab Utilisat Lasers Intenses, F-91128 Palaiseau, France. CEA, Dam Ile France, Dept Phys Theor & Appl, F-91680 Bruyeres Le Chatel, France. ENSTA, Lab Opt Appl, F-91128 Palaiseau, France. Ecole Polytech, Ctr Phys Theor, F-91128 Palaiseau, France. RP Faure, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Lefebvre, Erik/B-9835-2009; Malka, Victor/F-5260-2010 NR 27 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 717 EP 726 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300075 ER PT S AU Schroeder, CB Esarey, E Shadwick, BA Leemans, WP AF Schroeder, CB Esarey, E Shadwick, BA Leemans, WP BE Clayton, CE Muggli, P TI Raman forward scattering of high-intensity chirped laser pulses SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID ELECTRON ACCELERATION; TENUOUS PLASMAS; INSTABILITIES; PROPAGATION; IONIZATION; GENERATION AB Raman forward scattering of a high-intensity, short-duration, frequency-chirped laser pulse propagating in an underdense plasma is examined. The growth of the direct forward scattered light is calculated for a laser pulse with a linear frequency chirp in various spatiotemporal regimes. This includes a previously undescribed regime of strongly-coupled four-wave nonresonant interaction, which is important for relativistic laser intensities. In all regimes of forward scattering, it is shown that the growth rate increases (decreases) for positive (negative) frequency chirp. The effect of chirp on the growth rate is relatively minor, i.e., a few percent chirp yields few percent changes in the growth rates. Relation of these results to recent experiments is discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Schroeder, CB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. NR 27 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 737 EP 750 PG 14 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300077 ER PT S AU Sharma, P Shvets, G AF Sharma, P Shvets, G BE Clayton, CE Muggli, P TI New effects in relativistic Thomson scattering SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID PLASMAS; WAVES AB We discuss two essential features of high intensity laser-plasma interactions: time retardation and nonlinear figure-eight motion. we focus on the fundamental and 2-nd harmonic emission in the direction of laser polarization, and make two theoretical predictions. First, the intensity of 2-nd harmonic (n = 2) radiation in the polarization direction varies nonmonotonically with laser field intensity, and even vanishes for laser intensities near a (0) = 2.2. Second, there is a non-vanishing radiation at the fundamental (n = 1) harmonic in the polarization direction. These two effects are enabled by simultaneous occurrence of figure-eight motion and time retardation. We argue that the most effective way of detecting relativistic effects is by observing n = 1, 2 harmonics in the direction of polarization. Suggestions for the optimal acceptance angle of such a detector are also given. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Sharma, P (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 9 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 760 EP 769 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300079 ER PT S AU Geddes, CGR Catravas, PE Faure, J Toth, C VanTilborg, J Leemans, WP AF Geddes, CGR Catravas, PE Faure, J Toth, C VanTilborg, J Leemans, WP BE Clayton, CE Muggli, P TI Accelerator optimization using a network control and acquisition system SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE ID LASER-PULSES AB Accelerator optimization requires detailed study of many parameters, indicating the need for remote control and automated data acquisition systems. A control and data acquisition system based on a network of commodity PCs and applications with standards based interapplication communication is being built for the FOASIS accelerator facility. This system allows synchronous acquisistion of data at high (> 1Hz) rates and remote control of the accelerator at low cost, allowing detailed study of the acceleration process. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, LOASIS Grp, Berkeley, CA 94720 USA. RP Geddes, CGR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, LOASIS Grp, Berkeley, CA 94720 USA. NR 5 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 796 EP 801 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300082 ER PT S AU Brown, WJ Hartemann, FV Tremaine, AM Springer, PT Le Sage, GP Barty, CPJ Rosenzweig, JB Crane, JK Cross, RR Fittinghoff, DN Gibson, DJ Slaughter, DR Anderson, S AF Brown, WJ Hartemann, FV Tremaine, AM Springer, PT Le Sage, GP Barty, CPJ Rosenzweig, JB Crane, JK Cross, RR Fittinghoff, DN Gibson, DJ Slaughter, DR Anderson, S BE Clayton, CE Muggli, P TI Electron beam production and characterization for the PLEIADES Thomson x-ray source SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB We report on the performance of an S-band RF photocathode electron gun and accelerator for operation with the PLEIADES Thomson x-ray source at LLNL. Simulations of beam production, transport, and focus are presented. It is shown that a 1 ps, 500 pC electron bunch with a normalized emittance of less than 5 pimm-mrad can be delivered to the interaction point. Initial electron measurements are presented. Calculations of expected x-ray flux are also performed, demonstrating an expected peak spectral brightness Of 1 020 photons/s/mm(2) /mrad(2)/0.1% bandwidth. Effects of RF phase jitter are also presented, and planned phase measurements and control methods are discussed. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Brown, WJ (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave, Livermore, CA 94550 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 830 EP 838 PG 9 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300086 ER PT S AU Loos, H Carr, GL Doyuran, A Graves, WS Johnson, ED Krinsky, S Rose, J Sheehy, B Shaftan, TV Skaritka, J Yu, LH AF Loos, H Carr, GL Doyuran, A Graves, WS Johnson, ED Krinsky, S Rose, J Sheehy, B Shaftan, TV Skaritka, J Yu, LH BE Clayton, CE Muggli, P TI Electron bunch compression and coherent effects at the SDL SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB The DUVFEL accelerator in the Source Development Lab of NSLS/BNL generates a high brightness electron beam from a laser driven electron source and a magnetic bunch compressor. This beam is used for different FEL experiments in SASE and future HGHG configurations. The compression of the electron beam to high peak current while preserving the transverse properties is of great importance to the performance goals of these FELs. In this paper we report on the experimental methods to characterize the longitudinal properties of the electron beam and the measured results for various settings of the DUVFEL accelerator. The observed effects on the electron beam spectra and time profiles during compression are most likely due to coherent effects while their exact origin is still subject of ongoing investigation. C1 Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Loos, H (reprint author), Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RI Shaftan, Timur/A-8443-2009 NR 13 TC 3 Z9 3 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 849 EP 857 PG 9 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300088 ER PT S AU Wangler, TP Qiang, J AF Wangler, TP Qiang, J BE Clayton, CE Muggli, P TI Los alamos beam halo experiment: Comparing theory, simulation, and experiment SO ADVANCED ACCELERATOR CONCEPTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th Workshop on Advanced Accelerator Concepts CY JUN 22-28, 2002 CL MANDALAY BEACH, CA SP US DOE AB We compare macroparticle simulations with measurements from a proton beam-halo experiment in a 52-quadrupole periodic-focusing channel. In the simulations, three different initial distributions with the same Courant-Snyder parameters and emittances, but different shapes, predict different mismatched-beam profiles in the transport system. Input distributions with greater population in the tails produce larger rates of emittance growth, a result that is qualitatively consistent with the particle-core model of halo formation in mismatched beams. The simulations underestimate the emittance growth rate for mismatched beams. Better agreement between simulations and experiment for mismatched beams may require an input distribution that represents more accurately the tails of the real input beam. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Wangler, TP (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 9 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 0-7354-0102-0 J9 AIP CONF PROC PY 2002 VL 647 BP 878 EP 883 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Fluids & Plasmas SC Engineering; Physics GA BV93U UT WOS:000180453300091 ER PT S AU DiMasi, E Gower, LB AF DiMasi, E Gower, LB BE Moss, SC TI Synchrotron X-ray observations of a monolayer template for mineralization SO ADVANCED BIOMATERIALS-CHARACTERIZATION, TISSUE ENGINEERING AND COMPLEXITY SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposia on Physical Characterization of Biological Materials and Systems/Polymeric Biomaterials for Tissue Engineering/BioInspired Materials-Moving Toward Complexity CY NOV 26-29, 2001 CL BOSTON, MA SP Mat Res Soc ID DIRECTED INORGANIC CRYSTALLIZATION; LANGMUIR MONOLAYERS; CALCIUM-CARBONATE; ORIENTED NUCLEATION; ACID MONOLAYERS; FILMS AB Mineral nucleation at a Langmuir film interface has been studied by synchrotron x-ray scattering. Diluted calcium bicarbonate solutions were used as, subphases for arachidic and stearic acid monolayers, compressed in a Langmuir trough. Self-assembly of the monolayer template is observed directly, and subsequent crystal growth monitored in-situ. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP DiMasi, E (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 11 TC 4 Z9 4 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-647-8 J9 MATER RES SOC SYMP P PY 2002 VL 711 BP 301 EP 306 PG 6 WC Engineering, Biomedical; Materials Science, Biomaterials SC Engineering; Materials Science GA BU92B UT WOS:000177402200044 ER PT B AU Young, KM AF Young, KM BE Stott, PE Wootton, A Gorini, G Sindoni, E Batani, D TI Alpha-particle measurements needed for burning plasma experiments SO ADVANCED DIAGNOSTICS FOR MAGNETIC AND INERTIAL FUSION LA English DT Proceedings Paper CT International Conference on Advanced Diagnostics for Magnetic and Inertial Fusion CY SEP 03-07, 2001 CL VARENNA, ITALY SP Int Ctr Promot Sci, Int Sch Plasma Phys, CNR, Ist Fis Plasma ID TOKAMAK PLASMAS; JET; EMISSION C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Young, KM (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Gorini, Giuseppe/H-9595-2016 OI Gorini, Giuseppe/0000-0002-4673-0901 NR 17 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-306-47297-X PY 2002 BP 59 EP 66 PG 8 WC Instruments & Instrumentation; Optics; Physics, Fluids & Plasmas; Spectroscopy SC Instruments & Instrumentation; Optics; Physics; Spectroscopy GA BV10Z UT WOS:000177840700009 ER PT B AU Izumi, N Lerche, RA Moran, MJ Phillips, TW Sangster, TC Schmid, GJ Stoyer, MA Disdier, L Bourgade, JL Rouyer, A Fisher, RK Berggren, RR Caldwell, SE Faulkner, JR Mack, JM Oertel, JA Young, CS Glebov, VY Jaanimagi, PA Meyerhofer, DD Soures, JM Stoeckl, C Frenje, JA Li, CK Petrasso, RD AF Izumi, N Lerche, RA Moran, MJ Phillips, TW Sangster, TC Schmid, GJ Stoyer, MA Disdier, L Bourgade, JL Rouyer, A Fisher, RK Berggren, RR Caldwell, SE Faulkner, JR Mack, JM Oertel, JA Young, CS Glebov, VY Jaanimagi, PA Meyerhofer, DD Soures, JM Stoeckl, C Frenje, JA Li, CK Petrasso, RD BE Stott, PE Wootton, A Gorini, G Sindoni, E Batani, D TI Nuclear diagnostics of ICF SO ADVANCED DIAGNOSTICS FOR MAGNETIC AND INERTIAL FUSION LA English DT Proceedings Paper CT International Conference on Advanced Diagnostics for Magnetic and Inertial Fusion CY SEP 03-07, 2001 CL VARENNA, ITALY SP Int Ctr Promot Sci, Int Sch Plasma Phys, CNR, Ist Fis Plasma ID INERTIAL CONFINEMENT FUSION; NATIONAL-IGNITION-FACILITY; NEUTRON; ENERGIES; TARGETS; OMEGA C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Izumi, N (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI IZUMI, Nobuhiko/J-8487-2016; Gorini, Giuseppe/H-9595-2016 OI IZUMI, Nobuhiko/0000-0003-1114-597X; Gorini, Giuseppe/0000-0002-4673-0901 NR 17 TC 0 Z9 0 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-306-47297-X PY 2002 BP 99 EP 106 PG 8 WC Instruments & Instrumentation; Optics; Physics, Fluids & Plasmas; Spectroscopy SC Instruments & Instrumentation; Optics; Physics; Spectroscopy GA BV10Z UT WOS:000177840700015 ER PT B AU Skinner, CH Federici, G AF Skinner, CH Federici, G BE Stott, PE Wootton, A Gorini, G Sindoni, E Batani, D TI Tritium issues in next step devices SO ADVANCED DIAGNOSTICS FOR MAGNETIC AND INERTIAL FUSION LA English DT Proceedings Paper CT International Conference on Advanced Diagnostics for Magnetic and Inertial Fusion CY SEP 03-07, 2001 CL VARENNA, ITALY SP Int Ctr Promot Sci, Int Sch Plasma Phys, CNR, Ist Fis Plasma ID JET C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Skinner, CH (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 23 TC 5 Z9 5 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-306-47297-X PY 2002 BP 277 EP 284 PG 8 WC Instruments & Instrumentation; Optics; Physics, Fluids & Plasmas; Spectroscopy SC Instruments & Instrumentation; Optics; Physics; Spectroscopy GA BV10Z UT WOS:000177840700051 ER PT B AU Glenzer, SH AF Glenzer, SH BE Stott, PE Wootton, A Gorini, G Sindoni, E Batani, D TI Thomson scattering in inertial confinement fusion research SO ADVANCED DIAGNOSTICS FOR MAGNETIC AND INERTIAL FUSION LA English DT Proceedings Paper CT International Conference on Advanced Diagnostics for Magnetic and Inertial Fusion CY SEP 03-07, 2001 CL VARENNA, ITALY SP Int Ctr Promot Sci, Int Sch Plasma Phys, CNR, Ist Fis Plasma ID HOHLRAUM PLASMAS; LASER-PLASMA; WAVES; DRIVEN; NOVA C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Glenzer, SH (reprint author), Lawrence Livermore Natl Lab, POB 808,L-399, Livermore, CA 94551 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-306-47297-X PY 2002 BP 303 EP 310 PG 8 WC Instruments & Instrumentation; Optics; Physics, Fluids & Plasmas; Spectroscopy SC Instruments & Instrumentation; Optics; Physics; Spectroscopy GA BV10Z UT WOS:000177840700055 ER PT B AU Leeper, RJ Asay, JR Bailey, JE Bennett, GR Carlson, AL Chandler, A Cooper, GW Cuneo, M Deeney, C Dunham, G Fehl, DL Hanson, D Hall, CA Hurst, MJ Jobe, D Knudson, A Lake, P Lazier, SE McGurn, JS Mock, RC Moore, T Nash, TJ Nielsen, D Olson, RE Porter, J Pyle, J Rochau, GA Ruggles, LE Ruiz, CL Sanford, TWL Seamen, JF Seamen, JJ Simpson, WW Smelser, R Spielman, RB Stygar, WA Torres, JA Wenger, DF AF Leeper, RJ Asay, JR Bailey, JE Bennett, GR Carlson, AL Chandler, A Cooper, GW Cuneo, M Deeney, C Dunham, G Fehl, DL Hanson, D Hall, CA Hurst, MJ Jobe, D Knudson, A Lake, P Lazier, SE McGurn, JS Mock, RC Moore, T Nash, TJ Nielsen, D Olson, RE Porter, J Pyle, J Rochau, GA Ruggles, LE Ruiz, CL Sanford, TWL Seamen, JF Seamen, JJ Simpson, WW Smelser, R Spielman, RB Stygar, WA Torres, JA Wenger, DF BE Stott, PE Wootton, A Gorini, G Sindoni, E Batani, D TI Target diagnostic system for sandia national laboratories' Z facility SO ADVANCED DIAGNOSTICS FOR MAGNETIC AND INERTIAL FUSION LA English DT Proceedings Paper CT International Conference on Advanced Diagnostics for Magnetic and Inertial Fusion CY SEP 03-07, 2001 CL VARENNA, ITALY SP Int Ctr Promot Sci, Int Sch Plasma Phys, CNR, Ist Fis Plasma ID RAY; LASER C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Leeper, RJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 18 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-306-47297-X PY 2002 BP 355 EP 362 PG 8 WC Instruments & Instrumentation; Optics; Physics, Fluids & Plasmas; Spectroscopy SC Instruments & Instrumentation; Optics; Physics; Spectroscopy GA BV10Z UT WOS:000177840700064 ER PT B AU Johnson, D Efthimion, P Foley, J Jones, B Mazzucato, E Park, H Taylor, G Levinton, F Luhmann, N AF Johnson, D Efthimion, P Foley, J Jones, B Mazzucato, E Park, H Taylor, G Levinton, F Luhmann, N BE Stott, PE Wootton, A Gorini, G Sindoni, E Batani, D TI Diagnosis of st plasmas in NSTX - Challenges and opportunities SO ADVANCED DIAGNOSTICS FOR MAGNETIC AND INERTIAL FUSION LA English DT Proceedings Paper CT International Conference on Advanced Diagnostics for Magnetic and Inertial Fusion CY SEP 03-07, 2001 CL VARENNA, ITALY SP Int Ctr Promot Sci, Int Sch Plasma Phys, CNR, Ist Fis Plasma C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08540 USA. RP Johnson, D (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08540 USA. RI Gorini, Giuseppe/H-9595-2016 OI Gorini, Giuseppe/0000-0002-4673-0901 NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-306-47297-X PY 2002 BP 375 EP 378 PG 4 WC Instruments & Instrumentation; Optics; Physics, Fluids & Plasmas; Spectroscopy SC Instruments & Instrumentation; Optics; Physics; Spectroscopy GA BV10Z UT WOS:000177840700067 ER PT S AU Martin, M Wullschleger, S Garten, C AF Martin, M Wullschleger, S Garten, C BE VoDinh, T Buttgenbach, S TI Laser-induced breakdown spectroscopy for environmental monitoring of soil carbon and nitrogen SO ADVANCED ENVIRONMENTAL SENSING TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced Environmental Sensing Technology II CY OCT 31-NOV 01, 2001 CL NEWTON, MA SP SPIE DE laser-induced breakdown spectroscopy; LIBS of soils; LIBS for detection of soil carbon and nitrogen ID ENHANCED RAMAN-SPECTRA; HUMIC ACIDS; FULVIC-ACID; C-13; FLUORESCENCE; ELECTRODES; FRACTIONS; H-1; NMR AB Carbon reservoirs at the earth's surface comprise the plant and microbial, biomass, and organic and inorganic carbon in soils, lakes, rivers, and oceans. These reservoirs interact with the atmosphere and affect its CO2 content. Soil organic carbon (SOC) is an essential constituent in all ecosystems that can be enhanced by manipulating agricultural and forest lands. A successful strategy is the determination of the amount (quantity) and the chemical composition (quality) of carbon and nitrogen stored within the soil profile. The need for rapid analysis of both the soil quantity and quality is an essential part of determining the techniques of choice for measuring SOC. We have successfully demonstrated the technique of laser-induced breakdown spectroscopy (LEBS) in the determination of the total concentration of carbon and nitrogen in soils and have also been successful in the development of electrochemical-surface enhanced Raman spectroscopy (Electro-SERS), the results for which will be reported in another article. In this article we will focus on the data obtained using the LEBS technique. Our preliminary results suggest that LEBS method can be used for developing a field deployable instrument that can be used for in situ, real time monitoring of total carbon and nitrogen in soil. We have determined the total concentration of carbon in 15 soil samples and have obtained a calibration curve for them. C1 Oak Ridge Natl Lab, Environm Sci Div, Oak Ridge, TN 37831 USA. RP Martin, M (reprint author), Oak Ridge Natl Lab, Environm Sci Div, Oak Ridge, TN 37831 USA. RI Martin, Madhavi/A-5268-2011; Wullschleger, Stan/B-8297-2012; OI Wullschleger, Stan/0000-0002-9869-0446; Martin, Madhavi/0000-0002-6677-2180 NR 19 TC 12 Z9 12 U1 0 U2 6 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4304-2 J9 P SOC PHOTO-OPT INS PY 2002 VL 4576 BP 188 EP 195 DI 10.1117/12.456956 PG 8 WC Engineering, Environmental; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BU23F UT WOS:000175418200022 ER PT S AU Cullum, BM Mobley, J Wintenberg, AL Maples, RA Stokes, DL Vo-Dinh, T AF Cullum, BM Mobley, J Wintenberg, AL Maples, RA Stokes, DL Vo-Dinh, T BE VoDinh, T Buttgenbach, S TI Field-portable AOTF-based monitor technology for environmental sensing SO ADVANCED ENVIRONMENTAL SENSING TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced Environmental Sensing Technology II CY OCT 31-NOV 01, 2001 CL NEWTON, MA SP SPIE DE Raman spectroscopy; battery-operated; field-portable; environmental monitoring; AOTF; Acousto-optic tunable filter ID INDUCED BREAKDOWN SPECTROSCOPY; ENHANCED RAMAN SPECTROMETRY; BIOSENSOR; SENSORS; FILTER; METALS; PROBE; FIBER AB The development of a field-portable Raman instrument for environmental analyses is described. It is based on the use of a near-infrared frequency-stabilized diode laser for excitation, an acousto-optic tunable filter for wavelength selection, and an avalanche photodiode for detection. Evaluation of this instrument for the monitoring of environmentally important species will be discussed as well as its ability to be operated in room light without significantly increasing the background signal. In addition, we will also describe a baseline removal procedure based on second derivative approach that simplifies and increases the accuracy of the instrument's automated identification algorithm. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Vo-Dinh, T (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 37 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 0-8194-4304-2 J9 P SOC PHOTO-OPT INS PY 2002 VL 4576 BP 244 EP 254 DI 10.1117/12.456965 PG 11 WC Engineering, Environmental; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BU23F UT WOS:000175418200028 ER PT S AU Vestrand, WT Borozdin, K Brumby, S Casperson, D Fenimore, E Galassi, M McGowan, K Perkins, S Priedhorsky, W Starr, D White, R Wozniak, P Wren, J AF Vestrand, WT Borozdin, K Brumby, S Casperson, D Fenimore, E Galassi, M McGowan, K Perkins, S Priedhorsky, W Starr, D White, R Wozniak, P Wren, J BE Kibrick, RL TI The RAPTOR experiment: A system for monitoring the optical sky in real time SO ADVANCED GLOBAL COMMUNICATIONS TECHNOLOGIES FOR ASTRONOMY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced Global Communications Technologies for Astronomy II CY AUG 22-23, 2002 CL WAIKOLOA, HI SP SPIE DE optical transients; Sky monitoring; real-time processing; data mining; robotic telescopes; distributed sensors ID EARTH AB The Rapid Telescopes for Optical Response (RAPTOR) experiment is a spatially distributed system of autonomous robotic telescopes that is designed to monitor the sky for optical transients. The core of the system is composed of two telescope arrays, separated by 38 kilometers, that stereoscopically view the same 1500 square-degree field with a wide-field imaging array and a central 4 square-degree field with a more sensitive narrow-field "fovea" imager. Coupled to each telescope array is a real-time data analysis pipeline that is designed to identify interesting transients on timescales of seconds and, when a celestial transient is identified, to command the rapidly slewing robotic mounts to point the narrow-field "fovea" imagers at the transient. The two narrow-field telescopes then image the transient with higher spatial resolution and at a faster cadence to gather light curve information. Each "fovea" camera also images the transient through a different filter to provide color information. This stereoscopic monitoring array is supplemented by a rapidly slewing telescope with a low resolution spectrograph for follow-up observations of transients and a sky patrol telescope that nightly monitors about 10,000 square-degrees for variations, with timescales of a day or longer, to a depth about 100 times fainter. In addition to searching for fast transients, we will use the data stream from RAPTOR as a real-time sentinel for recognizing important variations in known sources. All of the data will be publically released through a virtual observatory called SkyDOT (Sky Database for Objects in the Time Domain) that we are developing for studying variability of the optical sky. Altogether, the RAPTOR project aims to construct a new type of system for discovery in optical astronomy-one that explores the time domain by "mining the sky in real time". C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Vestrand, WT (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. OI Priedhorsky, William/0000-0003-0295-9138 NR 25 TC 39 Z9 41 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 0-8194-4624-6 J9 P SOC PHOTO-OPT INS PY 2002 VL 4845 BP 126 EP 136 DI 10.1117/12.459515 PG 11 WC Engineering, Aerospace; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BV91R UT WOS:000180380200015 ER PT S AU Wren, J Borozdin, K Brumby, S Casperson, D Galassi, M McGowan, K Starr, D Vestrand, WT White, R Wozniak, P AF Wren, J Borozdin, K Brumby, S Casperson, D Galassi, M McGowan, K Starr, D Vestrand, WT White, R Wozniak, P BE Kibrick, RL TI A distributed control system for rapid astronomical transient detection SO ADVANCED GLOBAL COMMUNICATIONS TECHNOLOGIES FOR ASTRONOMY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced Global Communications Technologies for Astronomy II CY AUG 22-23, 2002 CL WAIKOLOA, HI SP SPIE DE RAPTOR; robotic; automated; telescope AB The Rapid Telescope for Optical Response (RAPTOR) program consists of a network of robotic telescopes dedicated to the search for fast optical transients. The pilot project is composed of three observatories separated by approximately 38 kilometers located near Los Alamos, New Mexico. Each of these observatories is composed of a telescope, mount, enclosure, and weather station, all operating robotically to perform individual or coordinated transient searches. The telescopes employ rapidly slewing mounts capable of slewing a 250 pound load 180 degrees in under 2 seconds with arcsecond precision. Each telescope consists of wide-field cameras for transient detection and a narrow-field camera with greater resolution and sensitivity. The telescopes work together by employing a closed-loop system for transient detection and follow-up. Using the combined data from simultaneous observations, transient alerts are generated and distributed via the Internet. Each RAPTOR telescope also has the capability of rapidly responding to external transient alerts received over the Internet from a variety of ground-based and satellite sources. Each observatory may be controlled directly, remotely, or robotically while providing state-of-health and observational results to the client and the other RAPTOR observatories. We discuss the design and implementation of the spatially distributed RAPTOR system. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Wren, J (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 5 TC 1 Z9 1 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 0-8194-4624-6 J9 P SOC PHOTO-OPT INS PY 2002 VL 4845 BP 156 EP 163 DI 10.1117/12.459507 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BV91R UT WOS:000180380200018 ER PT B AU Walters, LC Graham, J AF Walters, LC Graham, J GP OECD OECD TI The need to preserve nuclear fuels and materials knowledge SO ADVANCED REACTORS WITH INNOVATIVE FUELS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 2nd Workshop on Advanced Reactors with Innovative Fuels CY OCT 22-24, 2001 CL CHESTER, ENGLAND SP British Nucl Fuels Ltd AB The demand for nuclear power will likely substantially increase in this century. Developing countries are already including new nuclear plants as an important part of their mix of energy generators. The energy shortage in the United States coupled with the recent improvements in the economic competitiveness of nuclear power is causing a re-evaluation of the nuclear power enterprise. Even more important is the growing concern over CO2 emissions from fossil fuel combustion, the curbing of which could increase the price of the coal option still further. Nuclear energy reduces the CO2 burden directly by displacing fossil energy generation of electricity. In the future, the contribution of nuclear energy to the climate change problem may be even greater if nuclear energy is used for hydrogen generation in the transportation sector. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Walters, LC (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-19847-4 PY 2002 BP 35 EP 40 PG 6 WC Energy & Fuels; Nuclear Science & Technology SC Energy & Fuels; Nuclear Science & Technology GA BV20K UT WOS:000178154700002 ER PT B AU Chigrinov, SE Kiyavitskaya, HI Serafimovich, IG Rakhno, IL Rutkovskaia, CK Fokov, Y Khilmanovich, AM Marstinkevich, BA Bournos, VV Korneev, SV Mazanik, SE Kulikovskaya, AV Korbut, TP Voropaj, NK Zhouk, IV Kievec, MK AF Chigrinov, SE Kiyavitskaya, HI Serafimovich, IG Rakhno, IL Rutkovskaia, CK Fokov, Y Khilmanovich, AM Marstinkevich, BA Bournos, VV Korneev, SV Mazanik, SE Kulikovskaya, AV Korbut, TP Voropaj, NK Zhouk, IV Kievec, MK GP OECD OECD TI Experimental investigations of the accelerator-driven transmutation technologies at the subcritical facility "Yalina" SO ADVANCED REACTORS WITH INNOVATIVE FUELS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 2nd Workshop on Advanced Reactors with Innovative Fuels CY OCT 22-24, 2001 CL CHESTER, ENGLAND SP British Nucl Fuels Ltd AB The investigations on accelerator-driven transmutation technologies (ADTT) focus on the reduction of the amount of long-lived wastes and the physics of a subcritical system driven with an external neutron source. This paper presents the experimental facility "Yalina" which was designed and created at the Radiation Physics and Chemistry Problems Institute of the National Academy of Sciences of Belarus in the framework of the ISTC project #B-070 to study the peculiarities of ADTT in thermal spectrum. A detailed description of the assembly, neutron generator and a preliminary analysis of some calculated and experimental data (multiplication factor, neutron flux density distribution in the assembly, transmutation rates of some long-lived fission products and minor actinides) are presented. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Chigrinov, SE (reprint author), Fermilab Natl Accelerator Lab, MS 220,POB 500, Batavia, IL 60510 USA. NR 6 TC 0 Z9 0 U1 1 U2 1 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-19847-4 PY 2002 BP 413 EP 420 PG 8 WC Energy & Fuels; Nuclear Science & Technology SC Energy & Fuels; Nuclear Science & Technology GA BV20K UT WOS:000178154700037 ER PT S AU Hinoki, T Snead, LL Taguchi, T Igawa, N Yang, W Nozawa, T Katoh, Y Kohyama, A AF Hinoki, T Snead, LL Taguchi, T Igawa, N Yang, W Nozawa, T Katoh, Y Kohyama, A BE Kohyama, A Singh, M Lin, HT Katoh, Y TI Optimization and characterization of chemical vapor infiltrated SiC/SiC composites SO ADVANCED SIC/SIC CERAMIC COMPOSITES: DEVELOPMENTS AND APPLICATIONS IN ENERGY SYSTEMS SE CERAMIC TRANSACTIONS LA English DT Proceedings Paper CT International Symposium on SiC/SiC Composite Materials Research and Development and Its Application to Advanced Energy Systems CY MAY 20-22, 2002 CL KYOTO, JAPAN SP CREST ID SINTERED SIC FIBER; MECHANICAL-PROPERTIES; CERAMIC COMPOSITES AB SiC/SiC composites were fabricated by the forced-flow, thermal gradient chemical vapor infiltration (FCVI) method at the Oak Ridge National Laboratory (ORNL) and by the iso-thermal chemical vapor infiltration (ICVI) method at the Japanese National Institute for Materials Science (NIMS). The FCVI approach can fabricate relatively large composites in relatively short time, while the ICVI has significant controllability of fiber/matrix interphase formation. Fiber types included the near stoichiometric Tyranno SA and Hi-Nicalon Type-S. SiC/SiC composites 12.5 mm in thickness with either75 or 300 mm in diameter were fabricated at ORNL. SiC/SiC composites with 40 mm in diameter and 1.5similar to3.0 mm in thickness were fabricated at NIMS. The microstructure of these materials was studied using SEM with EDS and TEM while their mechanical properties were evaluated by tensile, flexural and single fiber push-out testing. Density, the uniformity of fiber/matrix interphase and mechanical properties improved by increasing fiber volume fraction, optimizing processing conditions for both the FCVI and the ICVI processes. Porosity was decreased to approximately 15%. The effect of the interphase on mechanical properties and fracture behavior were studied. Tensile strength of 2D composites reinforced with Tyranno SA fibers and with optimized multilayer SiC/C interphase was approximately 300 MPa. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hinoki, T (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Katoh, Yutai/0000-0001-9494-5862 NR 16 TC 7 Z9 7 U1 0 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-162-5 J9 CERAM TRANS PY 2002 VL 144 BP 55 EP 67 PG 13 WC Energy & Fuels; Materials Science, Ceramics; Materials Science, Characterization & Testing; Materials Science, Composites SC Energy & Fuels; Materials Science GA BX28G UT WOS:000184831400004 ER PT S AU Lara-Curzio, E AF Lara-Curzio, E BE Kohyama, A Singh, M Lin, HT Katoh, Y TI Development of test standards for continuous fiber ceramic composites in the United States SO ADVANCED SIC/SIC CERAMIC COMPOSITES: DEVELOPMENTS AND APPLICATIONS IN ENERGY SYSTEMS SE CERAMIC TRANSACTIONS LA English DT Proceedings Paper CT International Symposium on SiC/SiC Composite Materials Research and Development and Its Application to Advanced Energy Systems CY MAY 20-22, 2002 CL KYOTO, JAPAN SP CREST ID PARAMETERS; STRENGTHS AB The development of standardized test methods for the mechanical evaluation of ceramic matrix composites in the United States is reviewed. In particular, the activities of sub-committee C28.07 on Ceramic Matrix Composites of the American Society for Testing and Materials (ASTM) are reported. Efforts for international harmonization of test methods for these materials and their constituents are also discussed. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lara-Curzio, E (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 15 TC 0 Z9 0 U1 1 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-162-5 J9 CERAM TRANS PY 2002 VL 144 BP 191 EP 205 PG 15 WC Energy & Fuels; Materials Science, Ceramics; Materials Science, Characterization & Testing; Materials Science, Composites SC Energy & Fuels; Materials Science GA BX28G UT WOS:000184831400017 ER PT S AU Lin, HT Singh, M AF Lin, HT Singh, M BE Kohyama, A Singh, M Lin, HT Katoh, Y TI Evaluation of lifetime performance of Hi-Nicalon (TM) fiber-reinforced melt-infiltrated SiC ceramic composites SO ADVANCED SIC/SIC CERAMIC COMPOSITES: DEVELOPMENTS AND APPLICATIONS IN ENERGY SYSTEMS SE CERAMIC TRANSACTIONS LA English DT Proceedings Paper CT International Symposium on SiC/SiC Composite Materials Research and Development and Its Application to Advanced Energy Systems CY MAY 20-22, 2002 CL KYOTO, JAPAN SP CREST ID BORON-NITRIDE; ELEVATED-TEMPERATURES; MATRIX COMPOSITES; STRESS-RUPTURE; AIR; OXIDATION; STABILITY; CARBON AB Evaluation of lifetime performance of Hi-Nicalon(TM) fiber-reinforced SiC ceramic composites was carried out in four-point bending over a temperature range of 700degrees to 1300degreesC in air. The effects of number of harness and type of coating on the lifetime response were also evaluated in the present study. The composites consisted of similar to40 vol. % Hi-Nicalon(TM) fiber (8 or 5 harness satin weave) with a 0.5 mum BN (or C) fiber coating and a melt-infiltration SiC ceramic matrix. Lifetime results indicated that the Hi-Nicalon/MI SiC composites exhibited a stress-dependent lifetime at stress levels above an apparent fatigue limit, similar to the trend observed in CG-Nicalon(TM) fiber-reinforced CVI SiC matrix composites. The observed stress-dependent lifetime behavior was independent upon the number of harness and type of coating employed. However, results indicated that the lifetime performance of Hi-Nicalon/MI SiC composites could be greatly enhanced via the use of a higher number of harness satin weave and/or BN fiber coating. For SiC composites with BN fiber coating at temperatures less than or equal to 950degreesC, the lifetimes of Hi-Nicalon/MI SiC composites decreased with increases in applied stress level and test temperature. However, the lifetimes were extended as test temperature increased from 950degrees to 1150degreesC as a result of surface crack sealing due to a rapid SiO2 formation by the oxidation of MI SiC matrix. At temperatures > 1150degreesC the lifetime performance of SiC composites was limited by the onset of creep of Hi-Nicalon(TM) fibers. The lifetime governing processes in an oxidizing environment were generally attributed to the progressive oxidation of fiber coatings and subsequent formation of glassy phase(s), which formed a strong bond between fiber and matrix, resulting in embrittlement of the composite with time. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Lin, HT (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 29 TC 1 Z9 1 U1 1 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-162-5 J9 CERAM TRANS PY 2002 VL 144 BP 207 EP 220 PG 14 WC Energy & Fuels; Materials Science, Ceramics; Materials Science, Characterization & Testing; Materials Science, Composites SC Energy & Fuels; Materials Science GA BX28G UT WOS:000184831400018 ER PT S AU Lara-Curzio, E AF Lara-Curzio, E BE Kohyama, A Singh, M Lin, HT Katoh, Y TI A new standard test method for the tensile evaluation of ceramic fibers SO ADVANCED SIC/SIC CERAMIC COMPOSITES: DEVELOPMENTS AND APPLICATIONS IN ENERGY SYSTEMS SE CERAMIC TRANSACTIONS LA English DT Proceedings Paper CT International Symposium on SiC/SiC Composite Materials Research and Development and Its Application to Advanced Energy Systems CY MAY 20-22, 2002 CL KYOTO, JAPAN SP CREST DE fiber; testing; standard; strength; weibull; distribution; Monte carlo. ASTM; ceramic; composite; CFCC ID COMPOSITES AB In 1997 the jurisdiction of the former ASTM Standard Test Method D3379 "Standard Test Method for Tensile Strength and Young's Modulus for High-Modulus Single-Filament Materials" was transferred from ASTM committee D30 on High Modulus Fibers and Their Composites to committee C28 on Advanced Ceramics. One year later this document was withdrawn, in part because it was demonstrated that using the average of the cross-sectional area of a collection of fibers for the calculation of individual fiber strengths, as recommended by the standard, was inappropriate. This paper reviews the draft of a new ASTM test method for the tensile evaluation of single fibers, which incorporates provisions for addressing the deficiencies of the previous ASTM standard test method. At the time of this publication this test method was currently evolving through the internal ASTM balloting process on its way to becoming a standard. 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, POB 2008, Oak Ridge, TN 37831 USA. NR 11 TC 1 Z9 1 U1 1 U2 5 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-162-5 J9 CERAM TRANS PY 2002 VL 144 BP 233 EP 244 PG 12 WC Energy & Fuels; Materials Science, Ceramics; Materials Science, Characterization & Testing; Materials Science, Composites SC Energy & Fuels; Materials Science GA BX28G UT WOS:000184831400020 ER PT S AU Beach, RJ Feit, MD Brasure, LAD Payne, SA Mead, RW AF Beach, RJ Feit, MD Brasure, LAD Payne, SA Mead, RW BE Fermann, ME Marshall, LR TI Constant refractive index multi-core fiber laser SO ADVANCED SOLID-STATE LASERS, PROCEEDINGS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid-State Lasers CY FEB 03-06, 2002 CL Quebec City, CANADA SP Opt Soc Amer, IEEE Lasers & Electro Opt Soc AB A scalable fiber laser approach is described based on phase-locking multiple gain cores in an antiguided structure. The waveguide is comprised of periodic sequences of gain-and no-gain-loaded segments having uniform index, within the cladding region. Initial experimental results are presented. (C) 2002 Optical Society of America. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Beach, RJ (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. RI Feit, Michael/A-4480-2009 NR 2 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-697-4 J9 OSA TRENDS OPT PHOTO PY 2002 VL 68 BP 10 EP 15 PG 6 WC Optics; Physics, Applied SC Optics; Physics GA BAH79 UT WOS:000222298600003 ER PT S AU Bayramian, AJ Beach, RJ Behrendt, W Bibeau, C Ebbers, CA Freitas, BL Kanz, VK Payne, SA Schaffers, KI Skulina, KM Smith, LK Tassano, JB Van Lue, D AF Bayramian, AJ Beach, RJ Behrendt, W Bibeau, C Ebbers, CA Freitas, BL Kanz, VK Payne, SA Schaffers, KI Skulina, KM Smith, LK Tassano, JB Van Lue, D BE Fermann, ME Marshall, LR TI Initial experiments on Mercury, a 100 J 10 ns 10 Hz 10% efficiency diode pumped solid-state laser SO ADVANCED SOLID-STATE LASERS, PROCEEDINGS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid-State Lasers CY FEB 03-06, 2002 CL Quebec City, CANADA SP Opt Soc Amer, IEEE Lasers & Electro Opt Soc AB We report the activation of four 80 kW diode arrays, fabrication of four full aperture (4 x 6 x 0.75 cm) S-FAP slabs, an average power Pockels cell, transmitted wavefront, and gain measurements on the Mercury laser system. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Bayramian, AJ (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave,L-482, Livermore, CA 94550 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-697-4 J9 OSA TRENDS OPT PHOTO PY 2002 VL 68 BP 139 EP 143 PG 5 WC Optics; Physics, Applied SC Optics; Physics GA BAH79 UT WOS:000222298600033 ER EF