FN Thomson Reuters Web of Science™ VR 1.0 PT B AU Wangler, TP AF Wangler, TP GP OECD OECD OECD TI Reliable linac design for accelerator-driven subcritical reactor systems SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB Accelerator reliability corresponding to a very low frequency of beam interrupts is an important new accelerator requirement for accelerator-driven subcritical reactor systems. In this paper we review typical accelerator-reliability requirements and discuss possible methods for meeting these goals with superconducting proton-linac technology. 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 12 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 92-64-10211-6 PY 2003 BP 49 EP 58 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600004 ER PT B AU Maloy, SA James, MR Willcutt, G Sommer, WF Sokolov, M Snead, LL Hamilton, ML Garner, F AF Maloy, SA James, MR Willcutt, G Sommer, WF Sokolov, M Snead, LL Hamilton, ML Garner, F GP OECD OECD OECD TI The mechanical properties of 316L/304L stainless steels, Alloy 718 and Mod 9Cr-1Mo after irradiation in a spallation environment SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab DE tensile testing; radiation effects; accelerator production of tritium (APT); stainless steel; Alloy 718; Mod 9Cr-1Mo AB The accelerator production of tritium (APT) project proposes to use a 1.0 GeV, 100 mA proton beam to produce neutrons via spallation. reactions in a tungsten target. The neutrons are multiplied and moderated in a lead/aluminium/water blanket and then captured in 3 He to form tritium. The materials in the target and blanket region are exposed to protons and neutrons with energies into the GeV range. The effect of irradiation on the tensile and fracture toughness properties of candidate APT materials, 316L and 304L stainless steel (annealed), modified (Mod) 9Cr-1Mo steel, and Alloy 718 (precipitation hardened), was measured on tensile and fracture toughness specimens irradiated at the Los Alamos Neutron Science Center accelerator, which operates at an energy of 800 MeV and a current of 1 mA. The irradiation temperatures ranged from 50-164degreesC, prototypic of those expected in the APT target/blanket. The maximum achieved proton fluence was 4.5X10(21) p/cm(2) for the materials in the centre of the beam. This maximum exposure translates to a dpa of 12 and the generation of 10 000 appm H and 1000 appm He for the type 304L stainless steel tensile specimens. Specimens were tested at the irradiation temperature of 50-164degreesC. Less than 1 dpa of exposure reduced the uniform elongation of the Alloy 718 (precipitation hardened) and mod 9Cr-1Mo to less than 2%. This same dose reduced the fracture toughness by 50%. Approximately 4 dpa of exposure was required to reduce the uniform elongation of the austenitic stainless steels (304L and 316L) to less than 2%. The yield stress of the austenitic steels increased to more than twice its non-irradiated value after less than I dpa. The fracture toughness reduced significantly by 4 dpa to similar to100 MPa.m(1/2). These results are discussed and compared with results of similar materials irradiated in fission reactor environments. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Maloy, SA (reprint author), Los Alamos Natl Lab, MS H809, Los Alamos, NM 87545 USA. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 13 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 92-64-10211-6 PY 2003 BP 105 EP 124 PG 20 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600008 ER PT B AU Callaway, NT Ryder, RD AF Callaway, NT Ryder, RD GP OECD OECD OECD TI Beam reliability and equipment downtime tracking - How LANSCE closes the loop SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Callaway, NT (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-10211-6 PY 2003 BP 145 EP 150 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600011 ER PT B AU Valdiviez, R Schrage, D Shen, S Kishiyama, K AF Valdiviez, R Schrage, D Shen, S Kishiyama, K GP OECD OECD OECD TI The use of NEG vacuum pumps on the LEDA RFQ SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB The low energy demonstration accelerator (LEDA) radio frequency quadrupole (RFQ) accelerator utilises non-evaporable Getter (NEG) vacuum pumps on each of the six vacuum waveguides that couple RF power into the RFQ. The RFQ produces a 6.7 MeV proton beam at 100 mA under a CW condition. The peak RF power consumption of the RFQ is in the neighbourhood of 2.2 MW for 100 mA, CW beam operation [1]. The RF power is divided approximately equally amongst six waveguides, with each waveguide conducting a peak of approximately 367 kW of RF power. Each waveguide incorporates a vacuum pumping package that consists mainly of a NEG pump and a turbo pump. The NEG is the main pumping unit with a hydrogen pumping speed of about 1300 liters/sec. The performance of the NEG pumping units has been found to be very reliable at maintaining a waveguide vacuum level of approximately 2.0E-7 Torr under full power operating conditions. RFQ conditioning and operational tasks have been supported well by this vacuum pumping design. This paper will discuss the details of the waveguide vacuum pumping design, the NEG testing conducted to support the design, and the operational experience with the NEG pumping units. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Valdiviez, R (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-10211-6 PY 2003 BP 167 EP 174 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600014 ER PT B AU Lillard, RS Chandler, GT Ferguson, PD Gac, FD James, MR Maloy, SA Paciotti, MA Waters, LS Willcutt, GJ AF Lillard, RS Chandler, GT Ferguson, PD Gac, FD James, MR Maloy, SA Paciotti, MA Waters, LS Willcutt, GJ GP OECD OECD OECD TI Corrosion measurements on apt prototypic materials in the LANSCE high-power proton beam and applicability to other systems SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB The corrosion rates of several "corrosion resistant" materials behave in a similar manner even under the intense radiation of the LANSCE high-power beam. A second observation was made, showing that the corrosion rates saturated under high instantaneous radiation intensity in corrosion experiments conducted for the accelerator production of tritium (APT) programme. The LANSCE H+ beam is not prototypic of the proposed APT production plant in several respects. The instantaneous proton flux in the APT production plant beam is about 10 times that of the LANSCE beam. The small transverse APT beam spot is rastered to spread the power density over the area of the target, and as the beam rasters, it creates a pulsed character to the beam at a specific location. In order to develop correlations that would enable extrapolation of the corrosion data to the proposed APT production plant, the experimental programme included measurements over a range of average beam currents, measurements at high and low instantaneous beam current, and measurements at various combinations of pulse width and repetition rate. The correlations that were developed are based on an approximately linear dependence of corrosion rate on average beam current (average radiation intensity) and the saturation effect observed at high instantaneous radiation intensity. For a given transverse beam profile and for the same average beam current, the correlations predict the highest corrosion rate in a dc beam and the lowest corrosion rate in the lowest duty cycle beams. In the case of the APT extrapolation, the predicted corrosion rates were a factor of 5 lower than for a dc beam depositing the same average power density. The measured corrosion rates and the formulated extrapolations are applicable to water-cooled targets and components in proton beams. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lillard, RS (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 8 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-10211-6 PY 2003 BP 175 EP 192 PG 18 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600015 ER PT B AU James, MR Klann, RT Morgan, GL Pitcher, EJ Paciotti, MA Oostens, JM AF James, MR Klann, RT Morgan, GL Pitcher, EJ Paciotti, MA Oostens, JM GP OECD OECD OECD TI Preliminary measurements from a thick lead-bismuth target using 800 MeV protons SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB One of the major environmental issues facing the world is the safe, long-term storage of large amounts of plutonium and other actinides from retired weapons and the nuclear power industry. An accelerator-driven subcritical assembly is being explored as a way to bum these wastes. Such a system would use a beam of high-energy protons impinging on a target of lead-bismuth liquid eutectic for neutron production. Proper calculation of the neutron yield from such a target is required for the design of a surrounding subcritical assembly. To gather data on the neutron production, we irradiated a thick (10 cm radius, 50 cm length) target of lead-bismuth in the "Blue Room" facility at the Los Alamos Neutron Science Center. The target was irradiated with a 24 nA beam of 800 MeV protons, and the neutron spectra was measured at various locations along the target using both time-of-flight spectroscopy and activation foils. In addition, activation foils were placed downstream of a tungsten target (target 4) in a well-characterised neutron environment to establish the spectral unfolding technique. The experimental configuration and some preliminary results of these experiments are presented in the current work. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP James, MR (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-10211-6 PY 2003 BP 193 EP 200 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600016 ER PT B AU Haight, RC Devlin, M AF Haight, RC Devlin, M GP OECD OECD OECD TI Gas production cross-section measurements at LANSCE SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB We are measuring the production cross sections for hydrogen and helium production by neutrons from threshold to 100 MeV on structural materials of importance to the advanced accelerator application programme. Our approach is to measure the isotopes of hydrogen and helium as they are emitted in the nuclear reactions such as (n,xp), (n,xd), and (n,xalpha). The data include not only the production cross-sections but also the angular distributions and energy spectra of the emitted particles. These benchmark data also test nuclear reaction model calculations. Progress to date is reported. C1 Los Alamos Neutron Sci Ctr, Los Alamos, NM USA. RP Haight, RC (reprint author), Los Alamos Neutron Sci Ctr, Los Alamos, NM USA. RI Devlin, Matthew/B-5089-2013 OI Devlin, Matthew/0000-0002-6948-2154 NR 3 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-10211-6 PY 2003 BP 201 EP 208 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600017 ER PT B AU Cahalan, JE Eriksson, M AF Cahalan, JE Eriksson, M GP OECD OECD OECD TI Active and passive safety control performance in subcritical, accelerator-driven nuclear reactors SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB Traditional safety performance requirements for nuclear reactors have been developed for critical reactors, whose kinetics characteristics differ significantly from subcritical, accelerator-driven nuclear reactors. In a critical nuclear reactor, relatively small amounts of reactivity (negative or positive) can produce large changes in the fission rate. In subcritical reactors, the self-multiplication (k) decreases as the subcriticality (1-k) increases, and the responsiveness to small reactivity changes decreases. This makes subcritical nuclear reactors less responsive to positive reactivity insertions than critical reactors. Also, larger negative reactivity insertions are needed in subcritical reactors to shut down the fission chain if the neutron source remains. This paper presents the results from a computational analysis of the safety performance of subcritical, accelerator-driven nuclear reactors. Coupled kinetics and thermal-hydraulics models are used to quantify the effectiveness of traditional protection and control system designs in subcritical reactors. The analyses also quantify the role of inherent, passive reactivity feedback mechanisms in subcritical reactors. Computational results are used to develop conclusions regarding the most favourable and effective means for reactor control and protection in subcritical, accelerator-driven nuclear reactors. C1 Argonne Natl Lab, Reactor Anal & Engn Div, Argonne, IL 60439 USA. RP Cahalan, JE (reprint author), Argonne Natl Lab, Reactor Anal & Engn Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-10211-6 PY 2003 BP 237 EP 257 PG 21 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600020 ER PT B AU Boyack, BE Cappiello, MW Pasamehmetoglu, KO AF Boyack, BE Cappiello, MW Pasamehmetoglu, KO GP OECD OECD OECD TI Safe shutdown of accelerator-driven systems SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB Accelerator-driven systems have been and are being considered for several applications in which a spallation target is coupled to a subcritical multiplier or high-powered blanket. Examples are the accelerator production of tritium and accelerator transmutation of waste. Of primary importance for any accelerator-driven system is the need to demonstrate the safe shutdown of the system. In the United States, insights regarding the evolving design and regulatory requirements for the safe shutdown of accelerator-driven systems can be developed by considering the safety philosophies and approaches of the US Department of Energy (DOE) and the US Nuclear Regulatory Commission (NRC). Both the DOE and NRC approaches to safety emphasise the use of multiple layers of protection to prevent or mitigate the unintended release of radioactive material to the environment. In addition, however, there is a clear movement to employing simplified, inherent, and passive, means to accomplish safety functions in new reactor designs. In general, the use of inherent or passive safety features assures that the response to any upset condition is controlled by basic, inherent, physical processes, such as the expansion of metals with increasing temperature rather than the functioning of engineered components. In this changing design and regulatory environment, the challenge is to identify and employ basic, inherent, and passive physical processes to ensure the safe shutdown of accelerator-driven systems. In this paper we review the design and regulatory environment and explore several design approaches featuring both the functioning of engineered components and inherent features to produce the safe shutdown of accelerator-driven systems. C1 Los Alamos Natl Lab, Adv Accelerator Applicat Technol Dev Off, Los Alamos, NM 87545 USA. RP Boyack, BE (reprint author), Los Alamos Natl Lab, Adv Accelerator Applicat Technol Dev Off, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 1 U2 3 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-10211-6 PY 2003 BP 289 EP 298 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600022 ER PT B AU Dunn, FE AF Dunn, FE GP OECD OECD OECD TI Thermal response of the multiplier of an accelerator-driven system to beam interruptions SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB Thermal response of the multiplier of an accelerator-driven system to beam trips has been calculated for sodium cooled and lead-bismuth cooled multipliers. The temperature transients caused by a beam trip lead to thermal fatigue in structural components, and restoring the beam causes an additional temperature transient that adds to thermal fatigue. Design lifetimes for various multiplier components are calculated, based on the frequency of beam interruptions and on the thermal fatigue per interruption. Mitigation strategies to increase design lifetimes are discussed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Dunn, FE (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 5 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 92-64-10211-6 PY 2003 BP 345 EP 358 PG 14 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600026 ER PT B AU Cappiello, M Pasamehmetoglu, K Pitcher, E Guffee, R Chaves, W Willcutt, G AF Cappiello, M Pasamehmetoglu, K Pitcher, E Guffee, R Chaves, W Willcutt, G GP OECD OECD OECD TI Accelerator-driven test facility: Modular target and multiplier system concept design description SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB The accelerator-driven test facility (ADTF) modular design concept is a target/multiplier configuration that provides optimum flexibility in operation, and testing. The configuration proposed is based on demonstrated technologies and methods that are currently used in existing facilities. It consists of a centrally located target/multiplier experimental cell surrounded by shielding and three adjacent hot-cells. The experimental cell contains the neutron spallation source and two multiplier segments on either side. When assembled the system closely resembles a central spallation target with a surrounding multiplier in cylindrical geometry. At the completion of an irradiation cycle, target and multiplier components are moved into and out of the experimental cell horizontally from the adjoining hot-cells. All primary heat-removal equipment resides in the hot-cells providing for safe operation and maintenance. Scoping calculations show that reasonably high neutron flux levels are achievable over sufficient volume to meet the goals set for transmutation proof of performance tests. Using a safety by design strategy, a combination of active and passive safety features provide diverse and redundant beam shutdown and decay heat removal. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cappiello, M (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 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 92-64-10211-6 PY 2003 BP 359 EP 371 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600027 ER PT B AU Gohar, Y Finck, P Hanson, A Herceg, J Koploy, M Krajtl, L Mijatovic, P Pointer, WD Saiveau, J Sofu, T Todosow, M AF Gohar, Y Finck, P Hanson, A Herceg, J Koploy, M Krajtl, L Mijatovic, P Pointer, WD Saiveau, J Sofu, T Todosow, M GP OECD OECD OECD TI Lead-bismuth spallation target design of the accelerator-driven test facility (ADTF) SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB A design methodology for the lead-bismuth eutectic (LBE) spallation target has been developed and applied for the accelerator-driven test facility (ADTF) target. This methodology includes the target interface with the subcritical multiplier (SCM) of the ADTF and the different engineering aspects of the target design, physics, heat-transfer, hydraulics, structural, radiological, and safety analyses. Several design constrains were defined and utilised for the target design process to satisfy different engineering requirements and to minimise the time and the cost of the design development. Interface requirements with the subcritical multiplier were defined based on target performance parameters and material damage issues to enhance the lifetime of the target structure. Different structural materials were considered to define the most promising candidate based on the current database including radiation effects. The developed target design has a coaxial geometrical configuration to minimise the target footprint and it is installed vertically along the SCM axis. LBE is the target material and the target coolant with ferritic steel (HT-9 Alloy) structural material. The proton beam has 8.33 mA current uniformly distributed and 8.14 cm beam radius resulting in a current density of 40 muA/cm(2). The beam power is 5 MW and the proton energy is 600 MeV. The beam tube has 10 cm radius to accommodate the halo current. A hemi-spherical geometry is used for the target window, which is connected to the beam tube. The beam tube is enclosed inside two coaxial tubes to provide inlet and outlet manifolds for the LBE coolant. The inlet and the outlet coolant manifolds and the proton beam are entered from the top above the SCM. The paper describes the design criteria, engineering constraints, and the developed target design for the ADTF. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Gohar, Y (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT PI PARIS PA 2, RUE ANDRE PASCAL, CEDEX 16, 75775 PARIS, FRANCE BN 92-64-10211-6 PY 2003 BP 373 EP 383 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600028 ER PT B AU Tcharnotskaia, V Ammerman, C Woloshun, K AF Tcharnotskaia, V Ammerman, C Woloshun, K GP OECD OECD OECD TI Results from the initial operation of the LANL DELTA loop SO UTILISATION AND RELIABILITY OF HIGH POWER PROTON ACCELERATORS, WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 3rd Workshop on Utilisation and Reliability of High Power Proton Accelerators CY MAY 12-16, 2002 CL SANTA FE, NM SP OECD Nucl Energy Agcy, Nucl Sci Comm, Los Alamos Natl Lab AB This paper summarises results from the initial operation and shakedown testing of the recently constructed DELTA (development of lead-bismuth target applications) loop at Los Alamos National Laboratory. The DELTA loop was designed to study the long-term corrosive effects of liquid lead-bismuth eutectic (LBE) on structural materials at temperatures up to 500degreesC. The DELTA loop can also be used to study thermal and hydraulic properties of LBE flow in future spallation target designs. The first run of DELTA loop took place on 5 December 2001. Since then, several hours of shakedown testing have been performed. These tests include calibration of the magnetic flow meter; pump operation with flow velocities up to 4 m/s in the test section, natural convection operation at velocities up to 0.5m/s in the test section, isothermal flow operation at temperatures up to 375degreesC, and heat exchanger operation at different capacities. The loop is scheduled to be ready for long-term, unattended operation early this summer followed directly by a planned, 1000 hour material test. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Tcharnotskaia, V (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 3 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 92-64-10211-6 PY 2003 BP 385 EP 395 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BX09N UT WOS:000184283600029 ER PT S AU Hazen, TC Tien, AJ Worsztynowicz, A Altman, DJ Ulfig, K Manko, T AF Hazen, TC Tien, AJ Worsztynowicz, A Altman, DJ Ulfig, K Manko, T BE Sasek, V Glaser, JA Baveye, P TI Biopiles for remediation of petroleum-contaminated soils: A Polish case study - Polish Refinery biopile SO UTILIZATION OF BIOREMEDIATION TO REDUCE SOIL CONTAMINATION: PROBLEMS AND SOLUTIONS SE NATO Science Series IV-Earth and Environmental Sciences LA English DT Proceedings Paper CT NATO Advanced Research Workshop on the Utilization of Bioremediation to Reduce Soil Contamination CY JUN 14-19, 2000 CL PRAGUE, CZECH REPUBLIC SP NATO ID BIODEGRADATION AB The US Department of Energy and the Institute for Ecology of Industrial Areas of Poland demonstrated bioremediation techniques for the cleanup of acidic petroleum sludge impacted soils at an oil refinery in southern Poland. The waste was composed of high-molar mass paraffinic and polynuclear aromatic hydrocarbons. Benzo(a)pyrene and BTEX compounds were identified as the contaminants of concern. Approximately 3 300 m(3) of contaminated soil (TPH similar to 30 000 ppm) was targeted for treatment. A biopile design which employed a combination of passive and active aeration in conjunction with nutrient and surfactant application was used to increase the biodegradation of the contaminants of concern. Over the 20 month project, more than 81 % (120 metric tons) of petroleum hydrocarbons were biodegraded. Despite the fact that the material treated was highly weathered and very acidic, biodegradation rates of 121 mg per kg soil per day in the actively aerated side (82 mg per kg soil per day in the passive side) were achieved in this biopile. Microbial counts and dehydrogenase measurements gave the best correlation with the biodegradation rates. Costs were competitive or significantly lower when compared with other ex situ treatment processes. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Hazen, TC (reprint author), Lawrence Berkeley Lab, MS 70A-3317,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Hazen, Terry/C-1076-2012 OI Hazen, Terry/0000-0002-2536-9993 NR 27 TC 1 Z9 1 U1 3 U2 6 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1568-1238 BN 1-4020-1141-5 J9 NATO SCI S SS IV EAR JI NATO Sci. Series IV Earth Environ. Sciences PY 2003 VL 19 BP 229 EP 246 PG 18 WC Engineering, Environmental; Environmental Sciences; Soil Science; Toxicology SC Engineering; Environmental Sciences & Ecology; Agriculture; Toxicology GA BW49V UT WOS:000182216400021 ER PT S AU Bebek, C Akerlof, C Aldering, G Amanullah, R Astier, P Baltay, C Barrelet, E Basa, S Bercovitz, J Bergstrom, L Berstein, G Bester, M Bohlin, R Bonissent, A Bower, C Campbell, M Carithers, W Commins, E Day, C Deustua, S DiGennaro, R Ealet, A Ellis, R Emmett, W Eriksson, M Fouchez, D Fruchter, A Genat, JF Goldhaber, G Goobar, A Groom, D Heetderks, H Holland, S Huterer, D Johnston, W Kadel, R Karcher, A Kim, A Kolbe, W Lafever, R Lamoureaux, J Lampton, M Lefevre, O Levi, M Levin, D Linder, E Loken, S Malina, R Mazure, A McKay, T McKee, S Miquel, R Morgan, N Mortsell, E Mostek, N Mufson, S Musser, J Roe, N Nugent, P Oluseyi, H Pain, R Palaio, N Pankow, D Perlmutter, S Prieto, E Rabinowitz, D Refregier, A Rhodes, J Schubnell, M Sholl, M Smadja, G Smith, R Smoot, G Snyder, J Spadafora, A Szymkowiak, A Tarle, G Taylor, K Tilquin, A Tomasch, A Vincent, D von der Lippe, H Walder, JP Wang, G AF Bebek, C Akerlof, C Aldering, G Amanullah, R Astier, P Baltay, C Barrelet, E Basa, S Bercovitz, J Bergstrom, L Berstein, G Bester, M Bohlin, R Bonissent, A Bower, C Campbell, M Carithers, W Commins, E Day, C Deustua, S DiGennaro, R Ealet, A Ellis, R Emmett, W Eriksson, M Fouchez, D Fruchter, A Genat, JF Goldhaber, G Goobar, A Groom, D Heetderks, H Holland, S Huterer, D Johnston, W Kadel, R Karcher, A Kim, A Kolbe, W Lafever, R Lamoureaux, J Lampton, M Lefevre, O Levi, M Levin, D Linder, E Loken, S Malina, R Mazure, A McKay, T McKee, S Miquel, R Morgan, N Mortsell, E Mostek, N Mufson, S Musser, J Roe, N Nugent, P Oluseyi, H Pain, R Palaio, N Pankow, D Perlmutter, S Prieto, E Rabinowitz, D Refregier, A Rhodes, J Schubnell, M Sholl, M Smadja, G Smith, R Smoot, G Snyder, J Spadafora, A Szymkowiak, A Tarle, G Taylor, K Tilquin, A Tomasch, A Vincent, D von der Lippe, H Walder, JP Wang, G BE Siegmund, OHW TI SNAP satellite focal plane development SO UV/EUV AND VISIBLE SPACE INSTRUMENTATION FOR ASTRONOMY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on UV/EUV and Visible Space Instrumentation for Astronomy II CY AUG 07, 2003 CL SAN DIEGO, CA SP SPIE DE ASIC; CCD; optical filters; focal plane detectors; HgCdTe; InGaAs; spectrograph ID HIGH-RESISTIVITY SILICON; SUPERNOVAE AB The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R&D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to advance our preparedness for mission proposal in the areas of detectors and electronics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Bebek, C (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. OI malina, roger/0000-0003-3399-3865 NR 23 TC 4 Z9 4 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 0-8194-5037-5 J9 P SOC PHOTO-OPT INS PY 2003 VL 5164 BP 74 EP 83 DI 10.1117/12.505232 PG 10 WC Engineering, Aerospace; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BY24Y UT WOS:000188421200008 ER PT S AU Lampton, M Sholl, M Krim, M Besuner, R Akerlof, C Aldering, G Amanullah, R Astier, P Baltay, C Barrelet, E Basa, S Bebek, C Bercovitz, J Bergstrom, L Berstein, G Bester, M Bohlink, R Bonissent, A Bower, C Campbell, M Carithers, W Commins, E Day, C Deustua, S DiGennaro, R Ealet, A Ellis, R Emmett, W Eriksson, M Fouchez, D Fruchter, A Genat, JF Goldhaber, G Goobar, A Groom, D Heetderks, H Holland, S Huterer, D Johnston, W Kadel, R Karcher, A Kim, A Kolbe, W Lafever, R Lamoureaux, J Lefevre, O Levi, M Levin, D Linder, E Loken, S Malina, R Mazure, A McKay, T McKee, S Miquel, R Morgan, N Mortsell, E Mostek, N Mufson, S Musser, J Nugent, P Oluseyi, H Pain, R Palaio, N Pankow, D Perlmutter, S Prieto, E Rabinowitz, D Refregier, A Rhodes, J Roe, N Schubnell, M Smadja, G Smith, R Smoot, G Snyder, J Spadafora, A Szymkowiak, A Tarle, G Taylor, K Tilquim, A Tomasch, A Vincent, D von der Lippe, H Walder, JP Wang, G AF Lampton, M Sholl, M Krim, M Besuner, R Akerlof, C Aldering, G Amanullah, R Astier, P Baltay, C Barrelet, E Basa, S Bebek, C Bercovitz, J Bergstrom, L Berstein, G Bester, M Bohlink, R Bonissent, A Bower, C Campbell, M Carithers, W Commins, E Day, C Deustua, S DiGennaro, R Ealet, A Ellis, R Emmett, W Eriksson, M Fouchez, D Fruchter, A Genat, JF Goldhaber, G Goobar, A Groom, D Heetderks, H Holland, S Huterer, D Johnston, W Kadel, R Karcher, A Kim, A Kolbe, W Lafever, R Lamoureaux, J Lefevre, O Levi, M Levin, D Linder, E Loken, S Malina, R Mazure, A McKay, T McKee, S Miquel, R Morgan, N Mortsell, E Mostek, N Mufson, S Musser, J Nugent, P Oluseyi, H Pain, R Palaio, N Pankow, D Perlmutter, S Prieto, E Rabinowitz, D Refregier, A Rhodes, J Roe, N Schubnell, M Smadja, G Smith, R Smoot, G Snyder, J Spadafora, A Szymkowiak, A Tarle, G Taylor, K Tilquim, A Tomasch, A Vincent, D von der Lippe, H Walder, JP Wang, G BE MacEwen, HA TI SNAP telescope: an update SO UV/OPTICAL/IR SPACE TELESCOPES: INNOVATIVE TECHNOLOGIES AND CONCEPTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on UV/Optical/IR Space Telescopes CY AUG 03-05, 2003 CL San Diego, CA SP SPIE DE three-mirror telescopes; space astronomy; wide-field imaging ID 3-MIRROR TELESCOPES; SUPERNOVAE AB We present the baseline telescope design for the telescope for the SuperNova/Acceleration Probe (SNAP) space mission. SNAP's purpose is to determine expansion history of the Universe by measuring the redshifts, magnitudes, and spectral classifications of thousands of supernovae with unprecedented accuracy. Discovering and measuring these supemovae demand both a wide optical field and a high sensitivity throughout the visible and near IR wavebands. We have adopted the annular-field three-mirror anastigmat (TMA) telescope configuration, whose classical aberrations (including chromatic) are zero. We show a preliminary optmechanical design that includes important features for stray light control and on-orbit adjustment and alignment of the optics. We briefly discuss stray light and tolerance issues, and present a preliminary wavefront error budget for the SNAP Telescope. We conclude by describing some of the design tasks being carried out during the current SNAP research and development phase. C1 Lawrence Berkeley Lab, Berkeley, CA USA. RP Lampton, M (reprint author), Lawrence Berkeley Lab, Berkeley, CA USA. NR 13 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5039-1 J9 P SOC PHOTO-OPT INS PY 2003 VL 5166 BP 113 EP 123 PG 11 WC Engineering, Aerospace; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BY61H UT WOS:000189421200012 ER PT S AU Early, A Hyde, R Baron, B AF Early, A Hyde, R Baron, B BE MacEwen, HA TI Twenty meter space telescope based on diffractive Fresnel lens SO UV/OPTICAL/IR SPACE TELESCOPES: INNOVATIVE TECHNOLOGIES AND CONCEPTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on UV/Optical/IR Space Telescopes CY AUG 03-05, 2003 CL San Diego, CA SP SPIE AB Diffractive lenses offer two potential advantages for very large aperture space telescopes; very loose surface-figure tolerances and physical implementation as thin, flat optical elements. In order to actually realize these advantages one must be able to build large diffractive lenses with adequate optical precision and also to compactly stow the lens for launch and then fully deploy it in space. We will discuss the recent fabrication and assembly demonstration of a 5m glass diffractive Fresnel lens at LLNL. Optical performance data from smaller full telescopes with diffractive lens and corrective optics show diffraction limited performance with broad bandwidths. A systems design for a 20m space telescope will be presented. The primary optic can be rolled to fit inside of the standard fairings of the Delta IV vehicle. This configuration has a simple deployment and requires no orbital assembly. A twenty meter visible telescope could have a significant impact in conventional astronomy with eight times the resolution of Hubble and over sixty times the light gathering capacity. If the light scattering is made acceptable, this telescope could also be used in the search for terrestrial planets. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Early, A (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 7 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 0-8194-5039-1 J9 P SOC PHOTO-OPT INS PY 2003 VL 5166 BP 148 EP 156 PG 9 WC Engineering, Aerospace; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BY61H UT WOS:000189421200016 ER PT S AU Geib, KM Serkland, DK Allerman, AA Hargett, TW Choquette, KD AF Geib, KM Serkland, DK Allerman, AA Hargett, TW Choquette, KD BE Thienpont, H Danckaert, J TI High density interleaved VCSEL-RCPD arrays for optical information processing SO VCSELS AND OPTICAL INTERCONNECTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on VCSELs and Optical Interconnects CY OCT 30-NOV 01, 2002 CL BRUGGE, BELGIUM SP SPIE, European Opt Soc, IEE, TIMA Lab, COST270 DE VCSEL arrays; integrated VCSELs and detectors ID SURFACE-EMITTING LASER AB Vertical-cavity surface-emitting lasers (VCSELs) are uniquely suited for massively parallel interconnects and scannerless imaging applications due to their small size, high efficiency and amiability to formation of high-density 2-dimensional arrays. We have successfully fabricated 4096 element arrays (64x64) containing alternating rows of selectively-oxidized 850 run VCSELs and resonant-cavity photodetectors (RCPDs) on a 55 micron pitch monolithically integrated on semi-insulating GaAs substrates. We employ a matrix addressable architecture to reduce the input and output electrical connections to the array, where all the VCSELs (or RCPDs) in each row are connected by a common metal trace at the base of their mesas. The columns are connected by metal traces that bridge from mesa top to mesa top, connecting every other row (i.e., only VCSELs or only RCPDs). The design, fabrication and performance of these arrays is discussed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Geib, KM (reprint author), Sandia Natl Labs, POB 5800,MS 0603, Albuquerque, NM 87185 USA. NR 9 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 0-8194-4737-4 J9 P SOC PHOTO-OPT INS PY 2003 VL 4942 BP 207 EP 212 DI 10.1117/12.476226 PG 6 WC Optics SC Optics GA BW66N UT WOS:000182719600021 ER PT S AU Brislawn, CM Wohlberg, BE Percus, AG AF Brislawn, CM Wohlberg, BE Percus, AG BE Ebrahimi, T Sikora, T TI Resolution scalability for arbitrary wavelet transforms in the JPEG-2000 standard SO VISUAL COMMUNICATIONS AND IMAGE PROCESSING 2003, PTS 1-3 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Visual Communications and Image Processing 2003 CY JUL 08-11, 2003 CL LUGANO, SWITZERLAND SP SPIE, Soc Imaging Sci & Technol, IEEE Circuits & Syst Soc, European Assoc Signal Speech & Image Proc DE JPEG 2000; wavelet transform; lifting; filter bank; boundary conditions; image coding; resolution scalability AB A new set of boundary-handling algorithms has been developed for discrete wavelet transforms in the ISO/IEC JPEG-2000 Still Image Coding Standard. Two polyphase component extrapolation policies are specified: a constant extension policy and a symmetric extension policy. Neither policy requires any computations to generate the extrapolation. The constant extension policy is a low-complexity option that buffers just one sample from each end of the input being extrapolated. The symmetric extension policy has slightly higher memory and conditional-logic requirements but is mathematically equivalent to whole-sample symmetric pre-extension when used with whole-sample symmetric filter banks. Both policies can be employed with arbitrary lifted filter banks, and both policies preserve resolution scalability and reversibility. These extension policies will appear in Annex H, "Transformation of images using arbitrary wavelet transformations," in Part 2 ("Extensions") of the JPEG-2000 standard. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Brislawn, CM (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Wohlberg, Brendt/M-7764-2015 OI Wohlberg, Brendt/0000-0002-4767-1843 NR 16 TC 5 Z9 5 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 0-8194-5023-5 J9 P SOC PHOTO-OPT INS PY 2003 VL 5150 BP 774 EP 784 DI 10.1117/12.503231 PN 1-3 PG 11 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BX16A UT WOS:000184462900077 ER PT S AU Wohlberg, B Brislawn, C AF Wohlberg, B Brislawn, C BE Ebrahimi, T Sikora, T TI Reversible integer-to-integer transforms and symmetric extension of even-length filter banks SO VISUAL COMMUNICATIONS AND IMAGE PROCESSING 2003, PTS 1-3 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Visual Communications and Image Processing 2003 CY JUL 08-11, 2003 CL LUGANO, SWITZERLAND SP SPIE, Soc Imaging Sci & Technol, IEEE Circuits & Syst Soc, European Assoc Signal Speech & Image Proc DE lossless coding; JPEG2000; integer transform; wavelet transform; lifting; filter bank; reversible transform ID WAVELET TRANSFORMS AB The recent JPEG2000 image coding standard includes a lossless coding mode based on reversible integer to integer filter banks, which are constructed by inserting rounding operations into the filter bank lifting factorisation. The baseline (Part 1) of the JPEG2000 standard supports a single reversible filter bank, the finite length input to which is symmetrically extended to avoid difficulties at the boundaries. While designing support for arbitrary filter banks for Part 2 of the standard, we discovered that reversibility is not always possible for even length integer to integer filter banks combined with symmetric pre-extension. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Wohlberg, B (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Wohlberg, Brendt/M-7764-2015 OI Wohlberg, Brendt/0000-0002-4767-1843 NR 6 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-5023-5 J9 P SOC PHOTO-OPT INS PY 2003 VL 5150 BP 1709 EP 1718 DI 10.1117/12.503222 PN 1-3 PG 10 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BX16A UT WOS:000184462900169 ER PT S AU Edlund, KM Caudell, TP AF Edlund, KM Caudell, TP BE Erbacher, RF Chen, PC Roberts, JC Grohn, MT Borner, K TI A quantitative image-level evaluation of multi-resolution 3D texture-based volume rendering SO VISUALIZATION AND DATA ANALYSIS 2003 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 10th Annual Conference on Visualization and Data Analysis CY JAN 21-22, 2003 CL SANTA CLARA, CA SP Soc Imaging Sci & Technol, SPIE DE volume rendering; multi-resolution; image-level evaluation; normalized mutual information ID MUTUAL INFORMATION; SPECIFICATIONS; MAXIMIZATION; METRICS AB This research focuses on a quantitative evaluation of images produced by multi-resolution 3D texture-based volume rendering methods. Volume rendering techniques utilize nearly all the data in a volumetric data set to construct an image, so using coarser versions of the original data may negatively impact the display quality of the images produced. The trade-offs between a more efficient use of memory space needed to store a multi-resolution representation versus the potential sacrifice of image quality are characterized by visual inspection and by two image quality measurements: root mean square error (RMSE) and normalized mutual information (NMI). RMSE is a traditional image quality measurement and NMI is a recent technique used in image processing and human vision research that incorporates image entropies into a concise, intuitive information-based measurement to quantify information content. Using image entropy as a measure of information can help determine if there is some kind of structural artifact in the image, so it may compliment RMSE, which is often used to identify random error. The analysis of images produced from multi-resolution volume rendering experiments indicates that there is additional merit in looking at information-based measurements of image quality as well as using traditional measurements to identify and quantitatively evaluate regions of mismatch. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Edlund, KM (reprint author), Los Alamos Natl Lab, MS-B287, Los Alamos, NM 87545 USA. NR 34 TC 0 Z9 0 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 0-8194-4809-5 J9 P SOC PHOTO-OPT INS PY 2003 VL 5009 BP 133 EP 144 DI 10.1117/12.477529 PG 12 WC Computer Science, Information Systems; Imaging Science & Photographic Technology SC Computer Science; Imaging Science & Photographic Technology GA BX07E UT WOS:000184179600014 ER PT B AU Malladi, R Ravve, I AF Malladi, R Ravve, I BE Hege, HC Polthier, K TI Fast difference schemes for edge enhancing Beltrami flow and subjective surfaces SO VISUALIZATION AND MATHEMATICS III LA English DT Proceedings Paper CT 3rd International Workshop on Visualization and Mathematics CY MAY 22-25, 2002 CL BERLIN, GERMANY SP DFG Sonderforschungsbereich 288 DE Beltrami flow; subjective surfaces; unconditionally stable scheme; segmentation ID CURVATURE; ALGORITHMS; DIFFUSION AB Numerical integration of space-scale PDE is one of the most time consuming operation of image processing. The scale step is limited by conditional stability of explicit schemes. In this work, we introduce the uncondition ally stable semi-implicit linearized difference scheme for the Beltrami flow. The Beltrami flow [14, 15] is one of the most effective denoising algorithms in image processing. For gray-level images, we show that the Beltrami flow equation can be arranged in a reaction-diffusion form. This reveals the edge-enhancing properties of the equation and suggests the application of additive operator split (AOS) methods [4, 5] for faster convergence. As we show with numerical simulations, the AOS method results in an unconditionally stable semi-implicit linearized difference scheme in 2D and 3D. The values of the edge indicator function are used front the previous step in scale, while the pixel values of the next step are used to approximate the flow. The optimum ratio between the reaction and diffusion counterparts of the governing PDE is studied. We then apply this approach to fast subjective surface computation. The computational time decreases by a factor of 20 and more, as compared to the explicit scheme. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Comp Sci, Berkeley, CA 94720 USA. RP Malladi, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Comp Sci, Mail Stop 50A-1148,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-01295-8 PY 2003 BP 287 EP 302 PG 16 WC Computer Science, Software Engineering; Mathematics SC Computer Science; Mathematics GA BX40U UT WOS:000185177300015 ER PT B AU Hendricks, TJ AF Hendricks, TJ GP PEP PEP TI Multi-variable optimization of electrically-driven vehicle air-conditioning systems using transient performance analysis SO VTMS 6: VEHICLE THERMAL MANAGEMENT SYSTEMS LA English DT Proceedings Paper CT 6th Vehicle Thermal Management Systems Conference CY MAY 18-21, 2003 CL BRIGHTON, ENGLAND SP IMechE, SAE Int, Behr GmbH & Co KG, Valeo Engine Cooling, Air Int US Inc, MIRA, DANA Corp, Ricardo, Delphi Harrison, Solvay Fluor & Derivate GmbH AB The National Renewable Energy Laboratory (NREL) and U.S. Department of Energy (DOE) are interested in developing more efficient vehicle air conditioning (A/C) systems to reduce fuel consumption in advanced vehicle designs. Vehicle A/C systems utilizing electrically-driven compressors are one possible system design approach to increasing A/C system performance over various drive cycle conditions. NREL's transient A/C system model was used to perform multivariable design optimization of electrically-driven compressor A/C systems, in which five to seven system design variables were simultaneously optimized to maximize A/C system performance. Design optimization results demonstrate that significant improvements in system COP are possible, particularly system COP > 3, in a properly optimized system design with dynamically-controlled operation. System optimization analyses investigated dynamic A/C system design strategies employing dual-compressor-speeds in electrically-driven systems to evaluate their effects on system performance. A system optimization methodology was developed which can systematically quantify impacts on A/C system design and performance resulting from varying degrees of design influence being given to widely different design objectives. The technique is based upon formulating optimization objective functions from linear combinations of critical design performance parameters that characterize independent design goals. It was demonstrated here by giving varying degrees of design influence to maximizing system COP and maximizing evaporator cooling capacity over SC03 and US06 drive cycles. C1 Natl Renewable Energy Lab, Ctr Transportat Technol & Syst, Golden, CO USA. RP Hendricks, TJ (reprint author), Natl Renewable Energy Lab, Ctr Transportat Technol & Syst, Golden, CO USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU PROFESSIONAL ENGINEERING PUBLISHING LTD PI WESTMINISTER PA 1 BIRDCAGE WALK, WESTMINISTER SW1H 9JJ, ENGLAND BN 1-86058-418-7 PY 2003 BP 135 EP 148 PG 14 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BW88J UT WOS:000183458900011 ER PT B AU Rugh, JP AF Rugh, JP GP PEP PEP TI Application of an integrated modelling process to evaluate an automotive climate control system SO VTMS 6: VEHICLE THERMAL MANAGEMENT SYSTEMS LA English DT Proceedings Paper CT 6th Vehicle Thermal Management Systems Conference CY MAY 18-21, 2003 CL BRIGHTON, ENGLAND SP IMechE, SAE Int, Behr GmbH & Co KG, Valeo Engine Cooling, Air Int US Inc, MIRA, DANA Corp, Ricardo, Delphi Harrison, Solvay Fluor & Derivate GmbH DE integrated modeling; distributed HVAC; CFD; thermal comfort; auxiliary load reduction AB Automobile auxiliary loads significantly impact the fuel use of conventional and advanced vehicles. Improving the method for delivering conditioned air to the vehicle occupants is an effective way to reduce the amount of fuel used for climate control. A potential system for improved delivery of conditioned air is a distributed HVAC system consisting of under-seat heat and cooling units and ducting system. The goal at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is to assess thermal comfort, fuel economy, and emissions by using an integrated modeling approach composed of CAD, computational fluid dynamics (CFD), and thermal comfort tools. This paper presents the results of applying NREL's vehicle integrated modeling process to the distributed HVAC system. C1 Natl Renewable Energy Lab, Golden, CO USA. RP Rugh, JP (reprint author), Natl Renewable Energy Lab, Golden, CO USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU PROFESSIONAL ENGINEERING PUBLISHING LTD PI WESTMINISTER PA 1 BIRDCAGE WALK, WESTMINISTER SW1H 9JJ, ENGLAND BN 1-86058-418-7 PY 2003 BP 303 EP 312 PG 10 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BW88J UT WOS:000183458900026 ER PT J AU Brown, GS Barton, LL Thomson, BM AF Brown, GS Barton, LL Thomson, BM TI Permanganate oxidation of sorbed polycyclic aromatic hydrocarbons SO WASTE MANAGEMENT LA English DT Article ID OZONATION AB The polycyclic. aromatic hydrocarbons (PAH) that contaminate soils at many industrial and government sites are resistant to natural biotic and abiotic degradation processes. The recalcitrant nature of these compounds may require aggressive chemical treatment to effectively remediate these sites. This study was conducted to assess the viability of permanganate oxidative treatment as a method to reduce PAH concentration in contaminated soils. Study results demonstrated a reduction in soil sorbed concentration for a mixture of six PAHs that included anthracene, benzo(a)pyrene, chrysene, fluoranthene, phenanthrene, and pyrene by potassium permanganate (KMnO4) oxidative treatment. The greatest reduction in soil concentration was observed for benzo(a)pyrene, pyrene, phenanthrene, and anthracene at 72.1, 64.2, 56.2, and 53.8%, respectively, in 30 min at a KMnO4 concentration of 160 mM. Minimal reductions in fluoranthene and chrysene concentration were observed at 13.4 and 7.8%, respectively, under the same conditions. A relative chemical reactivity order of benzo(a)pyrene > pyrene > phenanthrene > anthracene > fluoranthene > chrysene towards permanganate ion was observed. Aromatic sextet theory was applied to the degradation results to explain the highly variable and compound-specific chemical reactivity order. (C) 2002 Elsevier Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Biol, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Civil Engn, Albuquerque, NM 87131 USA. RP Brown, GS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 15 TC 45 Z9 56 U1 9 U2 38 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0956-053X J9 WASTE MANAGE JI Waste Manage. PY 2003 VL 23 IS 8 BP 737 EP 740 AR PII S0956-053X(02)00119-8 DI 10.1016/S0956-053X(02)00119-8 PG 4 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 733QN UT WOS:000186012300007 PM 14522192 ER PT J AU Green, FB Lundquist, TJ Quinn, NWT Zarate, MA Zubieta, IX Oswald, WJ AF Green, FB Lundquist, TJ Quinn, NWT Zarate, MA Zubieta, IX Oswald, WJ TI Selenium and nitrate removal from agricultural drainage using the AIWPS (R) technology SO WATER SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 5th International IWA Conference on Waste Stabilisation Ponds CY APR 02-05, 2002 CL AUCKLAND, NEW ZEALAND SP IWA DE AIWPS((R)) technology; algal-bacterial; irrigation drainage; nitrate; selenium ID SAN-JOAQUIN VALLEY; DIMETHYL SELENIDE; WATER; IRRIGATION; PLANTS AB Monthly Maximum Discharge Limits (MMDL) have been established for selenium in irrigation drainage by the State of California and the U.S. Environmental Protection Agency following observations of avian teratogenesis at the Kesterson Reservoir in the San Joaquin Valley of California. As a result of these and other adverse effects, farmers and drainage districts on the western side of the San Joaquin Valley must reduce selenium concentrations in irrigation, drainage discharged to the San Joaquin River. Drainage treatment will be required in the near future to meet existing MMDL and future Total Maximum Discharge Limits (TMDL) for the San Joaquin River. A 0.4-hectare Algal Bacterial Selenium Removal (ABSR) Facility was designed and constructed at the Panoche Drainage District in 1995 and 1996 using the Advanced Integrated Wastewater Pond Systems(R) or AIWPS(R) Technology. Each of two physically identical systems combined a Reduction Pond (RP) with a shallow, peripheral algal High Rate Pond (HRP). A Dissolved Air Flotation (DAF) unit and a slow sand filter were used to remove particulate selenium from the effluent of each system. The two systems were operated under different modes of operation and the bacterial substrate varied in each system. The rates of nitrate and selenium removal were compared. Microalgae were harvested using DAF and used as a carbon-rich substrate for nitrate- and selenate-reducing bacteria. Mass removals of total soluble selenium of 77% or greater were achieved over a three-year period. Nitrate and selenate were removed by assimiliatory and dissimiliatory bacterial reduction, and nitrate was also removed by algal assimilation. The final removal of particulate selenium is the focus of ongoing investigations. The removal of particulate selenium is expected to increase the overall removal of selenium to greater than 90% and would allow farmers and drainage districts to discharge irrigation drainage in compliance with regulatory discharge limits. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Earth Sci, Hydroecol Engn & Adv Decis Support Grp,Ctr Enviro, Berkeley, CA 94720 USA. RP Green, FB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Earth Sci, Hydroecol Engn & Adv Decis Support Grp,Ctr Enviro, 1 Cyclotron Rd,MS 70A-3317, Berkeley, CA 94720 USA. RI Quinn, Nigel/G-2407-2015 OI Quinn, Nigel/0000-0003-3333-4763 NR 27 TC 12 Z9 12 U1 0 U2 5 PU I W A PUBLISHING PI LONDON PA ALLIANCE HOUSE, 12 CAXTON ST, LONDON SW1H0QS, ENGLAND SN 0273-1223 J9 WATER SCI TECHNOL JI Water Sci. Technol. PY 2003 VL 48 IS 2 BP 299 EP 305 PG 7 WC Engineering, Environmental; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA 724UH UT WOS:000185504700039 PM 14510224 ER PT J AU Tadesse, I Isoaho, SA Green, FB Puhakka, JA AF Tadesse, I Isoaho, SA Green, FB Puhakka, JA TI Removal of organics and nutrients from tannery effluent by advanced integrated wastewater pond systems (R) technology SO WATER SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 5th International IWA Conference on Waste Stabilisation Ponds CY APR 02-05, 2002 CL AUCKLAND, NEW ZEALAND SP IWA DE AIWPS (R) technology; fermentation pit; organics; nutrients; tannery effluent ID RATE OXIDATION PONDS; RATE ALGAL PONDS; STABILIZATION PONDS; PERFORMANCE; WASTEWATERS AB In this study, a pilot-scale experiment was carried out on a pre-settled combined tannery effluent from Modjo tannery, Ethiopia, to evaluate the feasibility of the Advanced Integrated Wastewater Pond Systems(R) or AIWPS(R) Technology, for the treatment of tannery effluent. The pilot-scale AIWPS(R) Facility was comprised of an Advanced Facultative Pond (AFP), Secondary Facultative Pond (SFP) and Maturation Pond (MP) all arranged in series. Three feed phases with low, moderate and overloading organic loading rates were applied to assess the organics and nutrients removal performances of the AlWPS(R) reactors. The overall organics removal performance of the AIWPS(R) Process was high, with removal efficiencies in the range of 90-98% for BOD5 and 86-92% for COD. Among the AIWPS(R) reactors, the AFP attained the highest organics removal efficiency with a BOD5 removal of 70-89%. BOD5 removal efficiencies of the SFP and MP were 34-65% and 30-40%, respectively. The AFP was also able to withstand a much higher volumetric organic loading rate (70% more) than the conventional open anaerobic ponds. The drop in BOD5 removal efficiency of the AFP at the overloading condition was only 7%, while the corresponding drop in the SFP was 29%. AIWPS(R) reactors achieved a cumulative ammonia removal efficiency of 85%. The highest ammonia removal (50-60%) occurred in the SFP, followed by the MP with removal efficiency of 20-26%. At the overloading condition the overall ammonia removal efficiency of the AIWPS(R) Facility decreased by 50%, while the BOD5, organics removal dropped by only 6%, signifying the higher vulnerability of ammonia removal mechanism to high loading conditions than the organics removal. The phosphorus removal in the AIWPS(R) Facility was erratic, with highest removal (up to 75%) occurring in the AFP. The lack of H2S odour nuisance from the AFP was mainly due to the proliferation of sulphide oxidizing anoxygenic photosynthetic pink bacteria of the genera: Thiocystis, Rhodobacter, Rhodospirillum and Rhodopseudomonas in the upper solar illuminated water layers of the AFP. C1 Tampere Univ Technol, Inst Environm Engn & Biotechnol, FIN-33101 Tampere, Finland. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Tadesse, I (reprint author), Tampere Univ Technol, Inst Environm Engn & Biotechnol, POB 541, FIN-33101 Tampere, Finland. RI Puhakka, Jaakko/G-4220-2014 NR 37 TC 12 Z9 14 U1 1 U2 9 PU I W A PUBLISHING PI LONDON PA ALLIANCE HOUSE, 12 CAXTON ST, LONDON SW1H0QS, ENGLAND SN 0273-1223 J9 WATER SCI TECHNOL JI Water Sci. Technol. PY 2003 VL 48 IS 2 BP 307 EP 314 PG 8 WC Engineering, Environmental; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA 724UH UT WOS:000185504700040 PM 14510225 ER PT S AU Bourgeat, P Meriaudeau, F Kenneth, WTA Gorria, P AF Bourgeat, P Meriaudeau, F Kenneth, WTA Gorria, P BE Truchetet, F TI Comparison of texture features for segmentation of patterned wafers SO WAVELET APPLICATIONS IN INDUSTRIAL PROCESSING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Wavelet Applications in Industrial Processing CY OCT 28-29, 2003 CL Providence, RI SP SPIE DE wafer inspection; wavelet transform; Gabor filtering; digital holography; segmentation ID FILTERS; RADAR AB In the last decade, the accessibility of inexpensive and powerful computers has allowed true digital holography to be used for industrial inspection using microscopy. This technique allows capturing a complex image of a scene, and reconstructing the phase and magnitude information. Digital holograms give a new dimension to texture analysis since the topology information can be used as an additional way to extract features. This new technique can be used to extend previous work on image segmentation of patterned wafers for defect detection. This paper presents a comparison between the features obtained using Gabor filtering on complex (i.e. containing magnitude and phase) images under illumination and focus variations. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Bourgeat, P (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Bourgeat, Pierrick/A-1419-2010 OI Bourgeat, Pierrick/0000-0002-2605-4766 NR 13 TC 0 Z9 0 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 0-8194-5154-1 J9 P SOC PHOTO-OPT INS PY 2003 VL 5266 BP 179 EP 190 PG 12 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BY76T UT WOS:000189458200018 ER PT S AU Barrett, CL Drozda, M Marathe, A Marathe, MV AF Barrett, CL Drozda, M Marathe, A Marathe, MV GP IEEE IEEE TI Analyzing interaction between network protocols, topology and traffic in wireless radio networks SO WCNC 2003: IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE RECORD, VOLS 1-3 SE IEEE Wireless Communications and Networking Conference LA English DT Proceedings Paper CT IEEE Wireless Communications and Networking Conference CY MAR 16-20, 2003 CL NEW ORLEANS, LA SP NTT Do Co Mo, Motorola, Nokia, Verizon, Ericsson, IEEE, IEEE Commun Soc DE ad-hoc networks; statistical analysis; interactions; ANOVA; MAC layer; routing layer AB We study the interaction between communication protocols, network topology and packet traffic in wireless static radio networks. A particular interest is to empirically characterize the effect of interaction between the routing layer and the MAC layer on overall system performance. Three well known MAC protocols: 802.11, CSMA, and MACA are considered. Similarly three recently proposed routing protocols: AODV, DSR and LAR scheme 1 are considered. The performance of the protocols is measured with regard to three important parameters: (i) number of packets received (ii) average latency of each packet and (iii) long term fairness. We use a simple statistical technique based on ANOVA (Analysis of Variance), to characterize the effect of interaction between protocols and various input parameters on network performance. This technique is of independent interest and can be utilized in other simulation studies. Using our methodology, we conclude that different combinations of routing and MAC protocols yield varying performance under varying network topology and traffic situations. Our results show that no combination of routing protocol and MAC protocol is the best over all situations. An important implication of the study is that the performance analysis of protocols at a given level in the protocol stack needs to be studied not locally in isolation but as a part of the complete protocol stack. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663,MS M997, Los Alamos, NM 87545 USA. NR 28 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1525-3511 BN 0-7803-7700-1 J9 IEEE WCNC PY 2003 BP 1760 EP 1766 PG 7 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BW67R UT WOS:000182770600310 ER PT J AU Vitek, JM David, SA Hinman, CR AF Vitek, JM David, SA Hinman, CR TI Improved ferrite number prediction model that accounts for cooling rate effects - Part 1: Model development - Details of a prediction model based on a neural network system of analysis are described SO WELDING JOURNAL LA English DT Article; Proceedings Paper CT 83rd Annual Meeting of the American-Welding-Society CY MAR 04-07, 2002 CL CHICAGO, ILLINOIS SP Amer Welding Soc DE ferrite number; neural network; duplex stainless steel; austenitic stainless steel; ferrite content; cooling rate; alloy composition; constitution diagram ID STEEL WELD METAL; AUSTENITIC STAINLESS-STEELS; SOLIDIFICATION; ALLOYS AB A new model, ORFN (Oak Ridge Ferrite Number), has been developed for predicting ferrite content in stainless steel welds. For the first time, ferrite content is predicted quantitatively as a function of alloy composition and cooling rate. The model is based on a neural network analysis of existing data supplemented with newly generated data. This paper describes the details of the model development. The procedure used to calculate the cooling rate in a simple but effective manner is presented. This paper also describes the necessary procedures that were used to convert volume percent ferrite measurements to Ferrite Number. Finally, the procedures used to identify the optimum neural network architecture are outlined. Results from the model, as well as an assessment of the prediction accuracy and comparison with predictions of other models are presented in a companion paper (Part 2). The model is equally valid for austenitic stainless steels and duplex stainless steels, as well as for both conventional arc welding and high cooling rate conditions prevalent during high energy beam welding such as laser beam welding and high-speed arc welding. C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Vitek, JM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 33 TC 25 Z9 25 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA 550 N W LEJEUNE RD, MIAMI, FL 33126 USA SN 0043-2296 J9 WELD J JI Weld. J. PD JAN PY 2003 VL 82 IS 1 BP 10S EP 17S PG 8 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 746VG UT WOS:000186767900016 ER PT J AU Murray, PE AF Murray, PE TI Commentary on GMAW parameter selection paper - Untitled SO WELDING JOURNAL LA English DT Editorial Material C1 Bechtel BWXT Idaho LLC, Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. RP Murray, PE (reprint author), Bechtel BWXT Idaho LLC, Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA 550 N W LEJEUNE RD, MIAMI, FL 33126 USA SN 0043-2296 J9 WELD J JI Weld. J. PD JAN PY 2003 VL 82 IS 1 BP 90 EP 91 PG 2 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 746VG UT WOS:000186767900011 ER PT J AU Hansen, LA Mathews, NE Hansen, RW Vander Lee, BA Lutz, RS AF Hansen, LA Mathews, NE Hansen, RW Vander Lee, BA Lutz, RS TI Genetic structure in striped skunks (Mephitis mephitis) on the Southern High Plains of Texas SO WESTERN NORTH AMERICAN NATURALIST LA English DT Article DE DNA fingerprinting; genetic structure; Mephitis mephitis; population genetics; striped skunks ID DNA FINGERPRINT ANALYSIS; POPULATION; MICROSATELLITE; POLYMORPHISM; VARIABILITY; DYNAMICS; RANGE; LOCI AB Genetic variation within populations reflects population-level social and demographic processes and influences how a population behaves as an evolutionary unit. We examined partitioning of genetic variation in striped skunks (Mephitis mephitis) from the Southern High Plains of Texas during 1994-1995. Sixty-nine male and 35 female skunks were sampled on four 12.8-km(2) study plots. Plot centers ranged from 17.6 to 61.6 km apart. We used multi-locus DNA fingerprinting with 2 probes, pV47 and CTTxAGG, to test 3 hypotheses: (1) females are more genetically similar to other females than males are to other males on the same plot (indicating greater female philopatry than male philopatry), (2) genetic similarity is greater within plots than among plots (indicating partitioning of genetic variation in space), and (3) genetic similarity of males decreases as the distance separating males increases (indicating geographic distance affects rates of gene flow). In general, males on a plot had lower average genetic similarity than females. Genetic similarity within plots was not different from genetic similarity among plots for males or for females. Genetic similarity of males did not decrease with increasing distance among plots. The lack of geographical genetic structure in striped skunks suggests at the scale of this study (<60 km) that gene flow of biparentally inherited genes is not distance-mediated. However, the higher similarity values for females than for males on the same plot supports an effect of male-biased dispersal and female philopatry on partitioning of genetic variation between sexes. C1 Texas Tech Univ, Dept Range & Wildlife Management, Lubbock, TX 79409 USA. US Geol Survey, Texas Cooperat Fish & Wildlife Res Unit, Biol Resources Div, Lubbock, TX 79404 USA. New Mexico Dept Game & Fish, Santa Fe, NM 87504 USA. RP Hansen, LA (reprint author), Los Alamos Natl Lab, Box 1663,MS M887, Los Alamos, NM 87544 USA. NR 35 TC 4 Z9 4 U1 2 U2 5 PU BRIGHAM YOUNG UNIV PI PROVO PA 290 LIFE SCIENCE MUSEUM, PROVO, UT 84602 USA SN 1527-0904 J9 WEST N AM NATURALIST JI West. North Am. Naturalist PD JAN PY 2003 VL 63 IS 1 BP 80 EP 87 PG 8 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 642CN UT WOS:000180786900010 ER PT S AU Tajima, H Kamae, T Uno, S Nakamoto, T Fukazawa, Y Mitanic, T Takahashi, T Nakazawa, K Okada, Y Nomachi, M AF Tajima, H Kamae, T Uno, S Nakamoto, T Fukazawa, Y Mitanic, T Takahashi, T Nakazawa, K Okada, Y Nomachi, M BE Trumper, JE Tananbaum, HD TI Low noise double-sided silicon strip detector for multiple-compton gamma-ray telescope SO X-RAY AND GAMMA-RAY TELESCOPES AND INSTRUMENTS FOR ASTRONOMY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on X-Ray and Gamma-Ray Telescopes and Instruments for Astronomy CY AUG 24-28, 2002 CL WAIKOLOA, HI SP SPIE DE gamma-ray; Compton telescope; Silicon Strip Detector; SSD; semiconductor detector ID READOUT AB A Semiconductor Multiple-Compton Telescope (SMCT) is being developed to explore the gamma-ray universe in an energy band 0.1-20 MeV, which is not well covered by the present or near-future gamma-ray telescopes. The key feature of the SMCT is the high energy resolution that is crucial for high angular resolution and high background rejection capability. We have developed prototype modules for a low noise Double-sided Silicon Strip Detector (DSSD) system which is an essential element of the SMCT. The geometry of the DSSD is optimized to achieve the lowest noise possible. A new front-end VLSI device optimized for low noise operation is also developed. We report on the design and test results of the prototype system. We have reached an energy resolution of 1.3 keV (FWHM) for 60 keV and 122 keV at 0degreesC. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Tajima, H (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 12 TC 33 Z9 33 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 0-8194-4630-0 J9 P SOC PHOTO-OPT INS PY 2003 VL 4851 BP 875 EP 884 DI 10.1117/12.461511 PN 1&2 PG 10 WC Astronomy & Astrophysics; Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology SC Astronomy & Astrophysics; Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology GA BW45N UT WOS:000182073600086 ER PT S AU Beiersdorfer, P Beck, B Becker, JA Lepson, JK Reed, KJ AF Beiersdorfer, P Beck, B Becker, JA Lepson, JK Reed, KJ BE Bianconi, A Marcelli, A Saini, NL TI X-ray emission from highly charged ions colliding with a relativistic electron beam in the SuperEBIT electron beam ion trap SO X-RAY AND INNER-SHELL PROCESSES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 19th International Conference on X-Ray and Inner-Shell Processes CY JUN 24-28, 2002 CL ROME, ITALY SP Univ Roma La Sapienza, Lab Nazl Frascati, ENEA, INRM ID EXCITATION CROSS-SECTIONS; 1S2S S-3(1) LEVEL; DIELECTRONIC-RECOMBINATION; LAMB SHIFT; 2S(1/2)-2P(3/2) LEVELS; LIFETIME MEASUREMENT; URANIUM IONS; FE-XXV; SPECTROMETER; POLARIZATION AB The high-energy electron beam ion trap SuperEBIT at the Lawrence Livermore National Laboratory allows the study of the x-ray emission from highly charged ions interacting with electrons with energy in excess of 200 keV. Radiation from ions as highly charged as Cf96+ has been produced this way. The facility is being used to investigate the contributions from quantum electrodynamics in heavy ions. Here the focus is lithiumlike ions, especially U89+, which provide the opportunity for the most accurate test of QED in highly charged ions. We have also used the facility to measure the degree of x-ray line polarization as a function of the energy of the electron collision energy. For example, we have studied the linear polarization of the K-shell emission lines of Fe24+ for electron-impact energies high as 120 keV. A new area of research is the investigation of nuclear excitation by electronic transitions. This is the inverse process of internal conversion, where an atomic x ray is absorbed by the nucleus resulting in an excited nuclear state. We are planning to study this process in Os-189 using 217 keV atomic x rays generated in the interaction with a 196 keV electron beam. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Beiersdorfer, P (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Bianconi, Antonio/J-3997-2013 OI Bianconi, Antonio/0000-0001-9795-3913 NR 48 TC 8 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0111-X J9 AIP CONF PROC PY 2003 VL 652 BP 131 EP 140 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Optics; Physics GA BW52R UT WOS:000182316700014 ER PT S AU Krassig, B Dunford, RW Kanter, EP Southworth, SH Young, L AF Krassig, B Dunford, RW Kanter, EP Southworth, SH Young, L BE Bianconi, A Marcelli, A Saini, NL TI Nondipolar photoionization of atoms SO X-RAY AND INNER-SHELL PROCESSES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 19th International Conference on X-Ray and Inner-Shell Processes CY JUN 24-28, 2002 CL ROME, ITALY SP Univ Roma La Sapienza, Lab Nazl Frascati, ENEA, INRM ID ANGULAR-DISTRIBUTION PARAMETERS; HELIUM; RESONANCE; ENERGIES AB Results of the nondipolar angular distribution parameter gamma are presented for two cases of photoionization with substantially different photon energies, Kr is in the hard x-ray regime, and He is in the vuv regime. The nondipolar asymmetries are apparent even at low energies. The presence of dipole and quadrupole resonances strongly modifies the energy dependence of the nondipolar asymmetry parameter gamma. Measurements of gamma can be used as a spectroscopic tool to characterize quadrupole resonances that are not accessible in photoabsorption measurements. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Krassig, B (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 19 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 0-7354-0111-X J9 AIP CONF PROC PY 2003 VL 652 BP 145 EP 152 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Optics; Physics GA BW52R UT WOS:000182316700016 ER PT S AU Southworth, SH Dunford, RW Kanter, EP Krassig, B Young, L Armen, GB Levin, JC Chen, MH Ederer, DL AF Southworth, SH Dunford, RW Kanter, EP Krassig, B Young, L Armen, GB Levin, JC Chen, MH Ederer, DL BE Bianconi, A Marcelli, A Saini, NL TI Double K-vacancy production by X-ray photoionization SO X-RAY AND INNER-SHELL PROCESSES SE AIP Conference Proceedings LA English DT Proceedings Paper CT 19th International Conference on X-Ray and Inner-Shell Processes CY JUN 24-28, 2002 CL ROME, ITALY SP Univ Roma La Sapienza, Lab Nazl Frascati, ENEA, INRM ID ELECTRON-IMPACT; CROSS-SECTIONS; HELIUM; IONIZATION; SINGLE; RANGE; STATE; SHELL; NEON; S-1 AB We have studied double K-shell photoionization of Ne and Mo (Z = 10 and 42) at the Advanced Photon Source. Double K-vacancy production in Ne was observed by recording the KK-KLL Auger hypersatellite spectrum. Comparison is made with calculations using the multiconfiguration Dirac-Fock method. For Mo, double K-vacancy production was observed by recording the Kalpha,beta fluorescence hypersatellite and satellite x rays in coincidence. From the intensities of the Auger or x-ray hypersatellites relative to diagram lines, the probabilities for double K-vacancy production relative to single K-vacancies were determined. These results, along with reported measurements on other atoms, are compared with Z-scaling calculations of the high-energy limits of the double-to-single K-shell photoionization ratio. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Southworth, SH (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 21 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 0-7354-0111-X J9 AIP CONF PROC PY 2003 VL 652 BP 188 EP 194 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Optics; Physics GA BW52R UT WOS:000182316700022 ER PT S AU Gemmell, DS AF Gemmell, DS BE Bianconi, A Marcelli, A Saini, NL TI Nuclear transitions induced by synchrotron x-rays SO X-RAY AND INNER-SHELL PROCESSES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 19th International Conference on X-Ray and Inner-Shell Processes CY JUN 24-28, 2002 CL ROME, ITALY SP Univ Roma La Sapienza, Lab Nazl Frascati, ENEA, INRM ID ELECTRON TRANSITION; 31-YR ISOMER; ACCELERATED EMISSION; GAMMA-RAYS; EXCITATION; HF-178; IRRADIATION; AUGER AB We discuss two rare but interesting processes by which synchrotron x-rays with energies up to about 100 keV may be used to induce nuclear transitions. In the NEET (Nuclear Excitation by Electronic Transition) process, an intense x-ray beam is employed to make vacancies, e.g. K-holes, in the atoms of a specific nuclear isotope. When a vacancy is filled by an electronic transition from a higher atomic level, there is some probability that instead of the usual x-ray or Auger emission, the nucleus of the atom itself will be excited. This is then followed by a nuclear decay exhibiting characteristic gamma-rays or other types of radiation, with time delays typical of the nuclear states involved. The probability for NEET increases when the energies of the atomic and the nuclear transitions become close. We address some theoretical aspects of the process and describe experimental efforts to observe it in Os-189 and Au-197. The second process to be discussed is the possibility of "triggering" the decay of a nuclear isomer by irradiation with an x-ray beam. We focus on the case of the 31-year, 2.4-MeV, 16+ isomer of Hf-178. There has been speculation that if one could isolate gram quantities, say, of this isomer and then have the capability to accelerate its decay in a controlled way, one would have a powerful triggerable source of enormous energy. This could be used to generate explosions, for rapid irradiations, or for more general energy-storage applications, depending on the rate of energy release. We describe attempts to observe this process. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Gemmell, DS (reprint author), Argonne Natl Lab, Div Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 35 TC 3 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 0-7354-0111-X J9 AIP CONF PROC PY 2003 VL 652 BP 239 EP 249 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Optics; Physics GA BW52R UT WOS:000182316700027 ER PT S AU Singh, A Baur, K Brennan, S Homma, T Kubo, N Pianetta, P AF Singh, A Baur, K Brennan, S Homma, T Kubo, N Pianetta, P BE Bianconi, A Marcelli, A Saini, NL TI Detection and characterization of trace element contamination on silicon wafers SO X-RAY AND INNER-SHELL PROCESSES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 19th International Conference on X-Ray and Inner-Shell Processes CY JUN 24-28, 2002 CL ROME, ITALY SP Univ Roma La Sapienza, Lab Nazl Frascati, ENEA, INRM ID SURFACE AB Increasing the speed and complexity of semiconductor integrated circuits requires advanced processes that put extreme constraints on the level of metal contamination allowed on the surfaces of silicon wafers. Such contamination degrades the performance of the ultrathin SiO2 gate dielectrics that form the heart of the individual transistors. Ultimately, reliability and yield are reduced to levels that must be improved before new processes can be put into production. It should be noted that much of this metal contamination occurs during the wet chemical etching and rinsing steps required for the manufacture of integrated circuits and industry is actively developing new processes that have already brought the metal contamination to levels beyond the measurement capabilities of conventional analytical techniques. The measurement of these extremely low contamination levels has required the use of synchrotron radiation total reflection x-ray fluorescence (SR-TXRF) where sensitivities 100 times better than conventional techniques have been achieved. This has resulted in minimum detection limits for transition metals of 8x10(7) atoms/cm(2). SR-TXRF studies of the amount of metal contamination deposited on a silicon surface as a function of pH and oxygen content of the etching solutions have provided insights into the mechanisms of metal deposition from solutions containing trace amounts of metals ranging from parts per trillion to parts per billion. Furthermore, by using XANES to understand the chemical state of the metal atoms after deposition, it has been possible to develop chemical models for the deposition processes. Examples will be provided for copper deposition from ultra pure water and acidic solutions. C1 Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Singh, A (reprint author), Stanford Synchrotron Radiat Lab, 2575 Sand Hill Rd, Stanford, CA 94309 USA. NR 7 TC 1 Z9 1 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 0-7354-0111-X J9 AIP CONF PROC PY 2003 VL 652 BP 472 EP 480 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Optics; Physics GA BW52R UT WOS:000182316700053 ER PT J AU Tran, CQ Barnea, Z de Jonge, MD Dhal, BB Paterson, D Cookson, DJ Chantler, CT AF Tran, CQ Barnea, Z de Jonge, MD Dhal, BB Paterson, D Cookson, DJ Chantler, CT TI Quantitative determination of major systematics in synchrotron x-ray experiments: seeing through harmonic components SO X-RAY SPECTROMETRY LA English DT Article ID RADIATION; MONOCHROMATORS; DIFFRACTION; ATTENUATION; CRYSTALS AB In line with an ongoing programme to determine accurately x-ray attenuation coefficients, we have developed a method for the quantitative determination of the effect on experimental results of monochromator harmonic components in a synchrotron beam. The technique can be adapted to suit a wide variety of experiments, and is of particular interest because it determines the effect of the harmonic components directly. This avoids the necessity for modelling and is therefore robust. Results of a direct determination of the effect of harmonic components illustrate the power of the technique. We extended the technique to quantify the effects of dark current-induced errors. Copyright (C) 2003 John Wiley Sons, Ltd. C1 Univ Melbourne, Sch Phys, Melbourne, Vic 3010, Australia. Argonne Natl Lab, Chem Mat CARS CAT, Argonne, IL 60439 USA. Argonne Natl Lab, SRI CAT, Argonne, IL 60439 USA. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. RP Tran, CQ (reprint author), Univ Melbourne, Sch Phys, Melbourne, Vic 3010, Australia. RI de Jonge, Martin/C-3400-2011; Chantler, Christopher/D-4744-2013; Tran, Chanh/M-7868-2015 OI Chantler, Christopher/0000-0001-6608-0048; NR 19 TC 31 Z9 31 U1 1 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0049-8246 J9 X-RAY SPECTROM JI X-Ray Spectrom. PD JAN-FEB PY 2003 VL 32 IS 1 BP 69 EP 74 DI 10.1002/xrs.630 PG 6 WC Spectroscopy SC Spectroscopy GA 642NV UT WOS:000180811200013 ER PT J AU Proffen, T Billinge, SJL Egami, T Louca, D AF Proffen, T Billinge, SJL Egami, T Louca, D TI Structural analysis of complex materials using the atomic pair distribution function - a practical guide SO ZEITSCHRIFT FUR KRISTALLOGRAPHIE LA English DT Article ID X-RAY-DIFFRACTION; RANDOM SEMICONDUCTOR ALLOYS; JAHN-TELLER DISTORTION; POWDER DIFFRACTION; LOCAL-STRUCTURE; HIGH-RESOLUTION; DIFFUSE-SCATTERING; LENGTH MISMATCH; RANGE ORDER; DISORDER AB Modem materials and their properties are often characterized by varying degrees of disorder. Routine crystallographic structure solution only reveals the average structure. The study of Bragg and diffuse scattering yields the local atomic arrangements holding the key to understanding increasingly complex materials. In this paper we review the pair distribution function technique used to unravel the local structure. We aim to give a practical overview and make this method easily accessible to the wider scientific community. C1 Los Alamos Natl Lab, LANSCE 12, Los Alamos, NM 87545 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP Proffen, T (reprint author), Los Alamos Natl Lab, LANSCE 12, MS H805, Los Alamos, NM 87545 USA. EM tproffen@lanl.gov RI Lujan Center, LANL/G-4896-2012; Proffen, Thomas/B-3585-2009 OI Proffen, Thomas/0000-0002-1408-6031 NR 54 TC 123 Z9 123 U1 7 U2 70 PU WALTER DE GRUYTER GMBH PI BERLIN PA GENTHINER STRASSE 13, D-10785 BERLIN, GERMANY SN 0044-2968 J9 Z KRISTALLOGR JI Z. Kristall. PY 2003 VL 218 IS 2 BP 132 EP 143 DI 10.1524/zkri.218.2.132.20664 PG 12 WC Crystallography SC Crystallography GA 656XW UT WOS:000181637200008 ER PT J AU Hertweck, B Libowitzky, E Schultz, AJ AF Hertweck, B Libowitzky, E Schultz, AJ TI The hydrogen bond system of Mn-leonite: neutron diffraction results in comparison with IR spectroscopic data SO ZEITSCHRIFT FUR KRISTALLOGRAPHIE LA English DT Article ID PHASE-TRANSITIONS; MINERALS; K2MN(SO4)2.4H2O AB Single-crystal Time-Of-Flight (TOF) neutron diffraction data of Mn-leonite, K2Mn(SO4)(2) . 4 H2O, were obtained at 110, 185 and 295 K. Two reversible phase transitions at low temperatures have been previously confirmed by optical, calorimetric, and X-ray data. The cause for the phase transitions of Mn-leonite is a dynamic disorder of sulphate groups at room temperature (C2/m), that freeze to an ordered structure (I2/a) at 205(l) K. At 169(l) K the crystal structure switches to another ordered phase (P21/a). In general. the investigation by neutron diffraction confirms the structures of the three phases and, in addition, reveals the changes of the hydrogen bond configurations which influence the cooperative arrangement of the tetrahedra during, the two successive phase transitions observed in Mn-leonite. IR spectroscopic measurements in the range of the O-H stretching frequencies yield a broad absorption band at similar to3200 cm(-1) that can only be resolved at low temperatures. A distance-frequency plot, calculated from the experimental data of low temperature neutron diffraction and IR spectroscopy is in agreement with correlation data from literature. C1 Univ Vienna, Inst Mineral & Kristallog, Geozenturm, A-1090 Vienna, Austria. Argonne Natl Lab, IPNS Div, Argonne, IL 60439 USA. RP Libowitzky, E (reprint author), Univ Vienna, Inst Mineral & Kristallog, Geozenturm, Althanstr 14, A-1090 Vienna, Austria. NR 14 TC 3 Z9 3 U1 0 U2 3 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0044-2968 J9 Z KRISTALLOGR JI Z. Kristall. PY 2003 VL 218 IS 6 BP 403 EP 412 DI 10.1524/zkri.218.6.403.20724 PG 10 WC Crystallography SC Crystallography GA 698PQ UT WOS:000184008300004 ER PT J AU Nellis, WJ Chau, R Edwards, PP Winter, R AF Nellis, WJ Chau, R Edwards, PP Winter, R TI The transition to the metallic state in alkali and low-Z fluids SO ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS LA English DT Article DE Mott transition; caesium; rubidium; hydrogen; nitrogen; oxygen ID GPA 1.4 MBAR; ELECTRICAL-CONDUCTIVITY; NONMETAL TRANSITION; HYDROGEN; OXYGEN AB We review here experiments that investigate how the electronic properties of five chemically dissimilar fluid elements, hydrogen, nitrogen, oxygen, rubidium and caesium, vary with density beyond their critical points. Remarkably, all five elements in their metallic regime have essentially the same electrical conductivities, close to the predicted minimum metallic conductivity of a high-temperature, disordered metallic fluid. The large differences in their respective metal-nonmetal transition densities are rationalized in terms of each chemical element's unique atomic properties of size (radial extent of electronic wave function, N. E Mott [1]) and electronic polarizability (K. F. Herzfeld and D. A. Goldhammer [2]). These experiments thereby highlight the pivotal role of atomic properties in dictating the metallic or nonmetallic status of chemical elements of the periodic classification. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Birmingham, Sch Chem, Birmingham B15 2TT, W Midlands, England. Univ Birmingham, Inst Met & mat Sci, Birmingham B15 2TT, W Midlands, England. Univ Dortmund, Dept Chem, D-44227 Dortmund, Germany. RP Nellis, WJ (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. OI Winter, Roland/0000-0002-3512-6928 NR 21 TC 5 Z9 5 U1 0 U2 0 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0942-9352 J9 Z PHYS CHEM JI Z. Phys. Chemie-Int. J. Res. Phys. Chem. Chem. Phys. PY 2003 VL 217 IS 7 BP 795 EP 802 DI 10.1524/zpch.217.7.795.20394 PG 8 WC Chemistry, Physical SC Chemistry GA 702NT UT WOS:000184230500004 ER PT S AU Finch, RJ Hanchar, JM AF Finch, RJ Hanchar, JM BE Hanchar, JM Hoskin, PWO TI Structure and chemistry of zircon and zircon-group minerals SO ZIRCON SE Reviews in Mineralogy & Geochemistry LA English DT Review CT Short Course on Zircon Related Research CY APR 03-04, 2003 CL FREIBURG, GERMANY SP Mineral Soc Amer ID RARE-EARTH ELEMENTS; HIGH-PRESSURE; CRYSTAL-STRUCTURE; CONTINENTAL-CRUST; THERMAL-EXPANSION; YTTRIUM VANADATE; HYDROTHERMAL SYNTHESIS; BRILLOUIN-SCATTERING; SCHEELITE TRANSITION; BISMUTH VANADATE C1 Argonne Natl Lab, Argonne, IL 60439 USA. George Washington Univ, Dept Earth & Environm Sci, Washington, DC 20006 USA. RP Argonne Natl Lab, 9500 S Cass Ave, Argonne, IL 60439 USA. RI Finch, Robert/D-9553-2013 OI Finch, Robert/0000-0001-9342-5574 NR 135 TC 142 Z9 146 U1 8 U2 52 PU MINERALOGICAL SOC AMER PI CHANTILLY PA 3635 CONCORDE PKWY STE 500, CHANTILLY, VA 20151-1125 USA SN 1529-6466 BN 0-93995-065-0 J9 REV MINERAL GEOCHEM JI Rev. Mineral. Geochem. PY 2003 VL 53 BP 1 EP 25 DI 10.2113/0530001 PG 25 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA BY41Q UT WOS:000189199900001 ER PT S AU Ewing, RC Meldrum, A Wang, LM Weber, WJ Corrales, LR AF Ewing, RC Meldrum, A Wang, LM Weber, WJ Corrales, LR BE Hanchar, JM Hoskin, PWO TI Radiation effects in zircon SO ZIRCON SE Reviews in Mineralogy & Geochemistry LA English DT Review CT Short Course on Zircon Related Research CY APR 03-04, 2003 CL FREIBURG, GERMANY SP Mineral Soc Amer ID IRRADIATION-INDUCED AMORPHIZATION; BEAM-INDUCED AMORPHIZATION; ALPHA-DECAY DAMAGE; MOLECULAR-DYNAMICS SIMULATION; RADIOACTIVITY-INDUCED DAMAGE; EXPERIMENTAL HYDROTHERMAL CONDITIONS; COMPLEX SILICATE STRUCTURES; HEAVY-ION BOMBARDMENT; METAMICT ZIRCON; NATURAL ZIRCON C1 Univ Michigan, Dept Geol Sci, Dept Nucl Engn & Radiol Sci, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Univ Michigan, Dept Geol Sci, Dept Nucl Engn & Radiol Sci, Dept Mat Sci & Engn, 1006 CC Little Bldg, Ann Arbor, MI 48109 USA. RI Weber, William/A-4177-2008 OI Weber, William/0000-0002-9017-7365 NR 152 TC 127 Z9 133 U1 7 U2 28 PU MINERALOGICAL SOC AMER PI CHANTILLY PA 3635 CONCORDE PKWY STE 500, CHANTILLY, VA 20151-1125 USA SN 1529-6466 BN 0-93995-065-0 J9 REV MINERAL GEOCHEM JI Rev. Mineral. Geochem. PY 2003 VL 53 BP 387 EP 425 DI 10.2113/0530387 PG 39 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA BY41Q UT WOS:000189199900014 ER PT J AU Heller, WT Abusamhadneh, E Finley, N Rosevear, PR Trewhella, J AF Heller, WT Abusamhadneh, E Finley, N Rosevear, PR Trewhella, J TI The solution structure of a cardiac troponin C-troponin I-troponin T complex shows a somewhat compact troponin c interacting with an extended troponin I-Troponin T component SO BIOCHEMISTRY LA English DT Article ID X-RAY-SCATTERING; SMALL-ANGLE SCATTERING; LIGHT-CHAIN KINASE; REGULATORY DOMAIN; SKELETAL-MUSCLE; NEUTRON-SCATTERING; CONFORMATIONAL-CHANGES; INHIBITORY PEPTIDE; BINDING; RESOLUTION AB We have investigated the structure of the cTnC-cTnI-cTnT(198-298) calcium-saturated, ternary cardiac troponin complex by small-angle scattering with contrast variation. Shape restoration was also applied to the scattering information resulting from the deuterated cTnC subunit, the unlabeled cTnI-cTnT(198-298) subunits, and the entire complex. The experimental results and modeling indicate that cTnC adopts a partially collapsed conformation, while the cTnI-cTnT(198-298) components have an extended, rod-like structure. Shape restoration applied to the X-ray scattering data and the entire contrast variation series suggest that cTnC and the cTnI-cTnT(198-298) component lie with their long axes roughly parallel to one another with a relatively small surface area for interaction. Our findings indicate that the nature of the interactions between TnC and the TnI-TnT component differs significantly between the cardiac and skeletal isoforms as evidenced by the different degrees of compactness between the cardiac TnC and skeletal TnC in their respective ternary complexes and the fact that the cTnC subunit is not highly intertwined with the other subunits, as observed in the binary complex of the skeletal isoforms. C1 Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Univ Cincinnati, Coll Med, Dept Mol Genet Biochem & Microbiol, Cincinnati, OH 45267 USA. RP Heller, WT (reprint author), Los Alamos Natl Lab, Biosci Div, POB 1663, Los Alamos, NM 87545 USA. OI Trewhella, Jill/0000-0002-8555-6766 FU NIAMS NIH HHS [AR 44324]; NIGMS NIH HHS [GM 40528] NR 69 TC 48 Z9 48 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 DEC 31 PY 2002 VL 41 IS 52 BP 15654 EP 15663 DI 10.1021/bi026687c PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 631MP UT WOS:000180171800022 PM 12501194 ER PT J AU Bowen, ME Engelman, DM Brunger, AT AF Bowen, ME Engelman, DM Brunger, AT TI Mutational analysis of synaptobrevin transmembrane domain oligomerization SO BIOCHEMISTRY LA English DT Article ID INTEGRAL MEMBRANE-PROTEIN; SYNAPTIC VESICLE; FUSION; EXOCYTOSIS; SYNAPTOPHYSIN; DIMERIZATION; MACHINERY; MECHANISM; SNARES; BRAIN AB Synaptobrevin 2 is thought to facilitate fusion of synaptic vesicles with the presynaptic membrane through formation of a soluble NSF attachment protein receptor complex (SNARE) with syntaxin la and a synaptosomal associated protein of 25 kDa (SNAP-25). Previous reports have described a homodimer of synaptobrevin that is dependent on the transmembrane domain. However, these reports disagree about the magnitude of dimerization, which makes it difficult to assess the biological relevance of this interaction. We used SDS-PAGE and the TOXCAT genetic assay to reexamine the homodimerization of the synaptobrevin transmembrane domain in detergents and the Escherichia coli inner membrane, respectively. To gauge the magnitude of synaptobrevin homodimerization, we used the well-characterized glycophorin A homodimer as a positive standard. In contrast to previous studies, we found synaptobrevin homodimerization in E. coli is very weak when compared to glycophorin A. Recombinant synaptobrevin forms a small amount of dimer and higher order oligomers in detergents that are highly dependent on solublization conditions. We estimate a dissociation constant of 10 mM for synaptobrevin dimerization in detergent. Thus, the dimerization of synaptobrevin in membranes is very weak, questioning any possible functional role for this association in vivo. C1 Stanford Univ, Howard Hughes Med Inst, Stanford, CA 94305 USA. Stanford Univ, Dept Mol & Cellular Physiol, Stanford, CA 94305 USA. Stanford Univ, Dept Neurol, Stanford, CA 94305 USA. Stanford Univ, Dept Neurol Sci, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Yale Univ, Dept Mol Biophys & Biochem, New Haven, CT 06520 USA. RP Brunger, AT (reprint author), Stanford Univ, Howard Hughes Med Inst, Stanford, CA 94305 USA. OI Brunger, Axel/0000-0001-5121-2036 FU NIMH NIH HHS [R01 MH 63105-01] NR 26 TC 35 Z9 36 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD DEC 31 PY 2002 VL 41 IS 52 BP 15861 EP 15866 DI 10.1021/bi0269411 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 631MP UT WOS:000180171800044 PM 12501216 ER PT J AU Gifford, AN Makriyannis, A Volkow, ND Gatley, SJ AF Gifford, AN Makriyannis, A Volkow, ND Gatley, SJ TI In vivo imaging of the brain cannabinoid receptor SO CHEMISTRY AND PHYSICS OF LIPIDS LA English DT Article; Proceedings Paper CT Symposium on Cannabinoids: Chemistry and Biology CY AUG 16-17, 2001 CL BETHESDA, MARYLAND SP Natl Inst Hlth DE cannabinoid receptors; positron emission tomography; PET; imaging ID I-123 LABELED AM251; CB1 RECEPTORS; MOUSE-BRAIN; IN-VIVO; BIODISTRIBUTION; ANALOGS; RADIOLIGAND; POTENT; BINDS; PET AB The CBI cannabinoid receptor is expressed in the brain at levels sufficient to serve as potential target for in vivo imaging using positron emission tomography (PET) or single photon emission computed tomography methodology. To date, the most promising radioligands for the in vivo imaging of this receptor have structures based on that of the cannabinoid antagonist, SR141716A. Rodent data obtained using these in vivo radiotracers has demonstrated that both the behavioral and neurochemical effects of cannabinoids occur at very low levels of receptor occupancy. More recently, an agonist radiotracer based on the structure of aminoalkylindole cannabinoids has also been examined for in vivo labeling of CBI receptors. Although rodent studies have indicated that in vivo imaging of CBI receptors is feasible, at the present time this receptor has still to be successful imaged in a human PET study. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Univ Connecticut, Dept Pharmaceut Sci, Storrs, CT 06269 USA. RP Gifford, AN (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. FU NIDA NIH HHS [DA12412] NR 17 TC 21 Z9 21 U1 0 U2 4 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0009-3084 J9 CHEM PHYS LIPIDS JI Chem. Phys. Lipids PD DEC 31 PY 2002 VL 121 IS 1-2 BP 65 EP 72 AR PII S0009-3084(02)00148-2 DI 10.1016/S0009-3084(02)00148-2 PG 8 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 642VU UT WOS:000180826800007 PM 12505691 ER PT J AU Reed, RN Shine, R Shetty, S AF Reed, RN Shine, R Shetty, S TI Sea Kraits (squamata : laticauda spp.) as a useful bioassay for assessing local diversity of eels (muraenidae, congridae) in the western Pacific Ocean SO COPEIA LA English DT Article ID BODY-SIZE; PROBABILITY; HABITS; SNAKES AB Collection of eels of the families Muraenidae and Congridae is often hampered by logistical and procedural difficulties. Sea kraits of the genus Laticauda may be useful bioassays for moray and conger eels in the western Pacific Ocean. Some widely distributed species of Laticauda appear to prey exclusively on eels, and these eels are readily palpated from snakes after they return to land to digest their prey. We removed 79 eels from 276 snakes on the island of Efate, Republic of Vanuatu, during November and December of 2000. Species diversity inferred from these eels was markedly different From the diversity inferred from eels from Vanuatu deposited in the Australian Museum, perhaps reflecting differential abilities of snakes and humans to capture certain eel species. This bioassay technique is inexpensive and logistically simple and may prove complementary to more traditional collecting methods. C1 Univ Sydney, Dept Biol Sci A08, Sydney, NSW 2006, Australia. Nanyang Technol Univ, Natl Inst Educ, Singapore 637616, Singapore. RP Reed, RN (reprint author), Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. RI Shine, Richard/B-8711-2008 NR 14 TC 19 Z9 19 U1 2 U2 3 PU AMER SOC ICHTHYOLOGISTS HERPETOLOGISTS PI CHARLESTON PA UNIV CHARLESTON, GRICE MARINE LABORATORY, 205 FORT JOHNSON RD, CHARLESTON, SC 29412 USA SN 0045-8511 J9 COPEIA JI Copeia PD DEC 31 PY 2002 IS 4 BP 1098 EP 1101 PG 4 WC Zoology SC Zoology GA 632TF UT WOS:000180238400023 ER PT J AU Feely, RA Sabine, CL Lee, K Millero, FJ Lamb, MF Greeley, D Bullister, JL Key, RM Peng, TH Kozyr, A Ono, T Wong, CS AF Feely, RA Sabine, CL Lee, K Millero, FJ Lamb, MF Greeley, D Bullister, JL Key, RM Peng, TH Kozyr, A Ono, T Wong, CS TI In situ calcium carbonate dissolution in the Pacific Ocean SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article DE CaCO(3) dissolution; anthropogenic CO(2); Pacific Ocean; aragonite saturation; calcite saturation; carbonate lysocline ID COCCOLITHOPHORE EMILIANIA-HUXLEYI; ANTHROPOGENIC CO2; ARAGONITE SATURATION; NORTH PACIFIC; ATMOSPHERIC CARBON; PARTICULATE MATTER; CHEMICAL LYSOCLINE; ORGANIC-MATTER; PANAMA BASIN; INDIAN-OCEAN AB Over the past several years researchers have been working to synthesize the WOCE/JGOFS global CO(2) survey data to better understand carbon cycling processes in the oceans. The Pacific Ocean data set has over 35,000 sample locations with at least two carbon parameters, oxygen, nutrients, CFC tracers, and hydrographic parameters. In this paper we estimate the in situ CaCO(3) dissolution rates in the Pacific Ocean water column. Calcium carbonate dissolution rates ranging from 0.01-1.1 mumol kg(-1) yr(-1) are observed in intermediate and deepwater beginning near the aragonite saturation horizon. In the North Pacific Intermediate Water between 400 and 800 m, CaCO(3) dissolution rates are more than 7 times faster than observed in middle and deep water depths (average=0.051 m mol kg(-1) yr(-1)). The total amount of CaCO(3) that is dissolved within the Pacific is determined by integrating excess alkalinity throughout the water column. The total inventory of CaCO(3) added by particle dissolution in the Pacific Ocean, north of 40degreesS, is 157 Pg C. This amounts to an average dissolution rate of approximately 0.31 Pg C yr(-1). This estimate is approximately 74% of the export production of CaCO(3) estimated for the Pacific Ocean. These estimates should be considered to be upper limits for in situ carbonate dissolution in the Pacific Ocean, since a portion of the alkalinity increase results from inputs from sediments. C1 NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Princeton Univ, Atmospher & Ocean Sci Program, Princeton, NJ 08544 USA. Oak Ridge Natl Lab, Carbon Dioxide Informat Anal Ctr, Oak Ridge, TN 37831 USA. Pohang Univ Sci & Technol, Sch Environm Sci & Engn, Pohang, South Korea. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. Hokkaido Natl Fisheries Res Inst, Kushiro 0850802, Japan. NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. NOAA, Pacific Marine Environm Lab, Univ Washington, Joint Inst Study Atmosphere & Oceans, Seattle, WA 98115 USA. Inst Ocean Sci, Sidney, BC V8L 4B2, Canada. RP Feely, RA (reprint author), NOAA, Pacific Marine Environm Lab, 7600 Sand Point Way NE, Seattle, WA 98115 USA. EM Richard.A.Feely@noaa.gov; Sabine@pmel.noaa.gov; ktl@postech.ar.kr; fmillero@rsmas.miami.edu; Roberts@pmel.noaa.gov; Greeley@pmel.noaa.gov; johnb@pmel.noaa.gov; key@princeton.edu; Tsung-Hung.Peng@noaa.gov; kozyr@ornl.gov; tono@fra.affrc.go.jp; wongcs@pac.dfo-mpo.gc.ca RI Lee, Kitack/G-7184-2015 NR 60 TC 88 Z9 89 U1 7 U2 44 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD DEC 31 PY 2002 VL 16 IS 4 AR 1144 DI 10.1029/2002GB001866 PG 12 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 649RQ UT WOS:000181222100002 ER PT J AU Van Wagoner, TM Crosson, RS Creager, KC Medema, G Preston, L Symons, NP Brocher, TM AF Van Wagoner, TM Crosson, RS Creager, KC Medema, G Preston, L Symons, NP Brocher, TM TI Crustal structure and relocated earthquakes in the Puget Lowland, Washington, from high-resolution seismic tomography SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article DE tomography; structure; Puget; earthquakes ID SOUTHERN VANCOUVER-ISLAND; CASCADIA FORE-ARC; WESTERN WASHINGTON; SEATTLE FAULT; VELOCITY STRUCTURE; SUBDUCTION COMPLEX; SOUND; STATE; ZONE; EVOLUTION AB The availability of regional earthquake data from the Pacific Northwest Seismograph Network (PNSN), together with active source data from the Seismic Hazards Investigation in Puget Sound (SHIPS) seismic experiments, has allowed us to construct a new high-resolution 3-D, P wave velocity model of the crust to a depth of about 30 km in the central Puget Lowland. In our method, earthquake hypocenters and velocity model are jointly coupled in a fully nonlinear tomographic inversion. Active source data constrain the upper 10-15 km of the model, and earthquakes constrain the deepest portion of the model. A number of sedimentary basins are imaged, including the previously unrecognized Muckleshoot basin, and the previously incompletely defined Possession and Sequim basins. Various features of the shallow crust are imaged in detail and their structural transitions to the mid and lower crust are revealed. These include the Tacoma basin and fault zone, the Seattle basin and fault zone, the Seattle and Port Ludlow velocity highs, the Port Townsend basin, the Kingston Arch, and the Crescent basement, which is arched beneath the Lowland from its surface exposure in the eastern Olympics. Strong lateral velocity gradients, consistent with the existence of previously inferred faults, are observed, bounding the southern Port Townsend basin, the western edge of the Seattle basin beneath Dabob Bay, and portions of the Port Ludlow velocity high and the Tacoma basin. Significant velocity gradients are not observed across the southern Whidbey Island fault, the Lofall fault, or along most of the inferred location of the Hood Canal fault. Using improved earthquake locations resulting from our inversion, we determined focal mechanisms for a number of the best recorded earthquakes in the data set, revealing a complex pattern of deformation dominated by general arc-parallel regional tectonic compression. Most earthquakes occur in the basement rocks inferred to be the lower Tertiary Crescent formation. The sedimentary basins and the eastern part of the Olympic subduction complex are largely devoid of earthquakes. Clear association of hypocenters and focal mechanisms with previously mapped or proposed faults is difficult; however, seismicity, structure, and focal mechanisms associated with the Seattle fault zone suggest a possible high-angle mode of deformation with the north side up. We suggest that this deformation may be driven by isostatic readjustment of the Seattle basin. C1 US Geol Survey, Menlo Pk, CA 94025 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Washington, Dept Earth & Space Sci, Seattle, WA 98195 USA. RP ChevronTexaco N Amer Upstream, 935 Gravier St, New Orleans, LA 70112 USA. EM thmv@chevrontexaco.com; crosson@u.washington.edu NR 54 TC 26 Z9 26 U1 1 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD DEC 31 PY 2002 VL 107 IS B12 AR 2381 DI 10.1029/2001JB000710 PG 23 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 649VM UT WOS:000181228700002 ER PT J AU Li, WG McCarthy, PA Liu, DG Huang, JY Yang, SC Wang, HL AF Li, WG McCarthy, PA Liu, DG Huang, JY Yang, SC Wang, HL TI Toward understanding and optimizing the template-guided synthesis of chiral polyaniline nanocomposites SO MACROMOLECULES LA English DT Article ID MOLECULAR-WEIGHT POLYANILINE; OPTICALLY-ACTIVE POLYANILINE; CONDUCTING POLYMERS; COLLOIDAL DISPERSIONS; POLY(ACRYLIC ACID); POLYMERIZATION; POLYPYRROLE; RECOGNITION; ABSORPTION; OXIDATION AB Previously we reported synthesis and characterization of water-soluble chiral conducting polymer nanocomposites via template-guided synthesis. Experimental procedures and parameters need to be carefully controlled to achieve synthesis of water-soluble nanocomposites. Here, we describe a modified synthetic procedure with higher molecular weight poly(acrylic acid) (PAA) (MW similar to 250 000) as a template. This new system allows synthesis of chiral water-soluble nanocomposites over a more broad range of conditions making the synthesis more reproducible and easier to carry out at large scale. Another objective of this work is to further understand the underlying formation mechanism of chiral polyaniline nanocomposites. We carried out a detailed study of how temperature, template, and solvent affect the final morphology and properties of these nanocomposites. We found that the extent of interaction and stability of the template/monomer/acid adduct (nanocomposite precursor) and population density of monomer surrounding the template are crucial in determining the degree of nanocomposite chirality. Detailed characterization of the nanocomposites and their precursors was carried out by circular dichroism (CD), UV-vis, FTIR, NMR, and TEM spectroscopy. On the basis of experimental results and synthetic procedures, a simplified model for the formation mechanism of chiral polyaniline nanocomposite is proposed. 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 32 TC 56 Z9 57 U1 0 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 31 PY 2002 VL 35 IS 27 BP 9975 EP 9982 DI 10.1021/ma020915t PG 8 WC Polymer Science SC Polymer Science GA 630CC UT WOS:000180089100018 ER PT J AU Acosta, D Affolder, T Akimoto, H Albrow, MG Ambrose, D Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Artikov, A Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Badgett, W Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Behari, S Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berryhill, J Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A Bromberg, C Brozovic, M Brubaker, E Bruner, N Budagov, J Budd, HS Burkett, K Busetto, G Byrum, KL Cabrera, S Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Castro, A Cauz, D Cerri, A Chan, AW Chang, PS Chang, PT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Chung, JY Chung, WH Chung, YS Ciobanu, CI Clark, AG Coca, M Colijn, AP Connolly, A Convery, M Conway, J Cordelli, M Cranshaw, J Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demers, S Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Dominguez, A Donati, S D'Onofrio, M Dorigo, T Dunietz, I Eddy, N Einsweiler, K Engels, E Erbacher, R Errede, D Errede, S Fan, Q Fang, HC Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Flores-Castillo, LR Foster, GW Franklin, M Freeman, J Friedman, J Frisch, HJ Fukui, Y Furic, I Galeotti, S Gallas, A Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Gerstein, E Giannetti, P Giolo, K Giordani, M Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gomez, G Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hahn, SR Hall, C Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hocker, A Hoffman, KD Hollebeek, R Holloway, L Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Ivanov, A Iwai, J Iwata, Y James, E Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Unel, MK Karr, K Kartal, S Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kilminster, B Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kondo, K Konigsberg, J Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Krutelyov, V Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lath, A Latino, G LeCompte, T Le, Y Lee, K Lee, SW Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, T Liu, YC Litvintsev, DO Lobban, O Lockyer, NS Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Manca, G Mariotti, M Martignon, G Martin, M Martin, A Martin, V Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P Menguzzato, M Menzione, A Merkel, P Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Miyazaki, Y Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nagaslaev, V Nahn, S Nakada, H Nakano, I Napora, R Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Nigmanov, T Niu, H Nodulman, L Nomerotski, A Oh, SH Oh, YD Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Onyisi, PUE Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Partos, D Patrick, J Pauletta, G Paulini, M Pauly, T Paus, C Pellett, D Pescara, L Phillips, TJ Piacentino, G Piedra, J Pitts, KT Pompos, A Pondrom, L Pope, G Pratt, T Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Rademacker, J Rakitine, A Ratnikov, F Reher, D Reichold, A Renton, P Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Rott, C Roy, A Ruiz, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Savoy-Navarro, A Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Sedov, A Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Sidoti, A Siegrist, J Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Snider, FD Solodsky, A Spalding, J Speer, T Spezziga, M Sphicas, P Spinella, F Spiropulu, M Spiegel, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Tecchio, M Tesarek, RJ Teng, PK Terashi, K Tether, S Thompson, AS Thomson, E Thurman-Keup, R Tipton, P Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Tonelli, D Tonnesmann, M Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Tsybychev, D Turini, N Ukegawa, F Vaiciulis, T Valls, J Vataga, E Vejcik, S Velev, G Veramendi, G Vidal, R Vila, I Vilar, R Volobouev, I von der Mey, M Vucinic, D Wagner, RG Wagner, RL Wagner, W Wallace, NB Wan, Z Wang, C Wang, MJ Wang, SM Ward, B Waschke, S Watanabe, T Waters, D Watts, T Weber, M Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkes, T Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Wu, X Wyss, J Yang, UK Yao, W Yeh, GP Yeh, P Yi, K Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Yun, JC Zanetti, A Zetti, F Zucchelli, S AF Acosta, D Affolder, T Akimoto, H Albrow, MG Ambrose, D Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Artikov, A Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Badgett, W Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Behari, S Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berryhill, J Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A Bromberg, C Brozovic, M Brubaker, E Bruner, N Budagov, J Budd, HS Burkett, K Busetto, G Byrum, KL Cabrera, S Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Castro, A Cauz, D Cerri, A Chan, AW Chang, PS Chang, PT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Chung, JY Chung, WH Chung, YS Ciobanu, CI Clark, AG Coca, M Colijn, AP Connolly, A Convery, M Conway, J Cordelli, M Cranshaw, J Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demers, S Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Dominguez, A Donati, S D'Onofrio, M Dorigo, T Dunietz, I Eddy, N Einsweiler, K Engels, E Erbacher, R Errede, D Errede, S Fan, Q Fang, HC Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Flores-Castillo, LR Foster, GW Franklin, M Freeman, J Friedman, J Frisch, HJ Fukui, Y Furic, I Galeotti, S Gallas, A Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Gerstein, E Giannetti, P Giolo, K Giordani, M Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gomez, G Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hahn, SR Hall, C Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hocker, A Hoffman, KD Hollebeek, R Holloway, L Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Ivanov, A Iwai, J Iwata, Y James, E Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Unel, MK Karr, K Kartal, S Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kilminster, B Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kondo, K Konigsberg, J Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Krutelyov, V Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lath, A Latino, G LeCompte, T Le, Y Lee, K Lee, SW Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, T Liu, YC Litvintsev, DO Lobban, O Lockyer, NS Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Manca, G Mariotti, M Martignon, G Martin, M Martin, A Martin, V Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P Menguzzato, M Menzione, A Merkel, P Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Miyazaki, Y Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nagaslaev, V Nahn, S Nakada, H Nakano, I Napora, R Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Nigmanov, T Niu, H Nodulman, L Nomerotski, A Oh, SH Oh, YD Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Onyisi, PUE Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Partos, D Patrick, J Pauletta, G Paulini, M Pauly, T Paus, C Pellett, D Pescara, L Phillips, TJ Piacentino, G Piedra, J Pitts, KT Pompos, A Pondrom, L Pope, G Pratt, T Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Rademacker, J Rakitine, A Ratnikov, F Reher, D Reichold, A Renton, P Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Rott, C Roy, A Ruiz, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Savoy-Navarro, A Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Sedov, A Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Sidoti, A Siegrist, J Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Snider, FD Solodsky, A Spalding, J Speer, T Spezziga, M Sphicas, P Spinella, F Spiropulu, M Spiegel, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Tecchio, M Tesarek, RJ Teng, PK Terashi, K Tether, S Thompson, AS Thomson, E Thurman-Keup, R Tipton, P Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Tonelli, D Tonnesmann, M Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Tsybychev, D Turini, N Ukegawa, F Vaiciulis, T Valls, J Vataga, E Vejcik, S Velev, G Veramendi, G Vidal, R Vila, I Vilar, R Volobouev, I von der Mey, M Vucinic, D Wagner, RG Wagner, RL Wagner, W Wallace, NB Wan, Z Wang, C Wang, MJ Wang, SM Ward, B Waschke, S Watanabe, T Waters, D Watts, T Weber, M Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkes, T Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Wu, X Wyss, J Yang, UK Yao, W Yeh, GP Yeh, P Yi, K Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Yun, JC Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Limits on extra dimensions and new particle production in the exclusive photon and missing energy signature in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID PARTON DISTRIBUTIONS; COLLIDER DETECTOR; HADRON COLLIDERS; GAMMA PRODUCTION; QCD CORRECTIONS; EVENTS; GRAVITINO; COUPLINGS; FERMILAB AB The exclusive gammais not an element of(T) signal has a small standard model cross section and is thus a channel sensitive to new physics. This signature is predicted by models with a superlight gravitino or with large extra spatial dimensions. We search for such signals at the Collider Detector at Fermilab, using 87 pb(-1) of data at roots = 1.8 TeV, and extract 95% C.L. limits on these processes. A limit of 221 GeV is set on the scale \F\(1/2) in supersymmetric models. For 4, 6, and 8 extra dimensions, model-dependent limits on the fundamental mass scale M-D of 0.55, 0.58, and 0.60 TeV, respectively, are found. We also specify a "pseudo-model-independent" method of comparing the results to theoretical predictions. C1 Univ Florida, Gainesville, FL 32611 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, CSIC, Inst Fis Cantabria, E-39005 Santander, Spain. Carnegie Mellon Univ, Pittsburgh, PA 15218 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Kyungpook Natl Univ, Ctr High Energy Phys, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Northwestern Univ, Evanston, IL 60208 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Oxford, Oxford OX1 3RH, England. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Toronto, Inst Particle Phys, Toronto, ON M5S 1A7, Canada. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Acosta, D (reprint author), Univ Florida, Gainesville, FL 32611 USA. RI Gallas Torreira, Abraham Antonio/K-6508-2014; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; Cabrera Urban, Susana/H-1376-2015; Introzzi, Gianluca/K-2497-2015; Gorelov, Igor/J-9010-2015; Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Ruiz, Alberto/E-4473-2011; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; manca, giulia/I-9264-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Ivanov, Andrew/A-7982-2013; Prokoshin, Fedor/E-2795-2012; Kim, Soo-Bong/B-7061-2014 OI Gallas Torreira, Abraham Antonio/0000-0002-2745-7954; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Gorelov, Igor/0000-0001-5570-0133; Ruiz, Alberto/0000-0002-3639-0368; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Ivanov, Andrew/0000-0002-9270-5643; Prokoshin, Fedor/0000-0001-6389-5399; NR 25 TC 38 Z9 38 U1 3 U2 21 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 DEC 31 PY 2002 VL 89 IS 28 AR 281801 DI 10.1103/PhysRevLett.89.281801 PG 7 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900008 PM 12513133 ER PT J AU Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Zghiche, A Palano, A Pompili, A Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Ofte, I Stugu, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Charles, E Gill, MS Gritsan, AV Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kolomensky, YG Kral, JF LeClerc, C Levi, ME Lynch, G Mir, LM Oddone, PJ Orimoto, TJ Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Harrison, TJ Hawkes, CM Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Lewandowski, B Peters, K Schmuecker, H Steinke, M Barlow, NR Bhimji, W Boyd, JT Chevalier, N Clark, PJ Cottingham, WN Mackay, C Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Blinov, VE Bukin, AD Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AP Serednyakov, SI Skovpen, YI Yushkov, AN Best, D Chao, M Kirkby, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DP Buchanan, C Chun, S Hadavand, HK Hill, EJ MacFarlane, DB Paar, H Prell, S Rahatlou, S Raven, G Schwanke, U Sharma, V Berryhill, JW Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Mazur, MA Richman, JD Verkerke, W Beringer, J Eisner, AM Grothe, M Heusch, CA Lockman, WS Pulliam, T Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GP Dvoretskii, A Hitlin, DG Porter, FC Ryd, A Samuel, A Yang, S Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Ford, WT Nauenberg, U Olivas, A Rankin, P Roy, J Smith, JG van Hoek, WC Zhang, L Harton, JL Hu, T Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Altenburg, D Brandt, T Brose, J Colberg, T Dickopp, M Dubitzky, RS Hauke, A Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Lavin, D Muheim, F Playfer, S Swain, JE Tinslay, J Falbo, M Borean, C Bozzi, C Piemontese, L Sarti, A Treadwell, E Anulli, F Baldini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Lo Vetere, M Macri, M Monge, MR Passaggio, S Pastore, FC Patrignani, C Robutti, E Santroni, A Tosi, S Bailey, S Morii, M Bartoldus, R Grenier, GJ Mallik, U Cochran, J Crawley, HB Lamsa, J Meyer, WT Rosenberg, EI Yi, J Davier, M Grosdidier, G Hocker, A Lacker, HM Laplace, S Le Diberder, F Lepeltier, V Lutz, AM Petersen, TC Plaszczynski, S Schune, MH Tantot, L Trincaz-Duvoid, S Wormser, G Bionta, RM Brigljevic, V Lange, DJ van Bibber, K Wright, DM Bevan, AJ Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Morton, GW Nash, JA Sanders, P Smith, D Taylor, GP Back, JJ Bellodi, G Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Cowan, G Flaecher, HU George, S Green, MG Kurup, A Marker, CE McMahon, TR Ricciardi, S Salvatore, F Vaitsas, G Winter, MA Brown, D Davis, CL Allison, J Barlow, RJ Forti, AC Jackson, F Lafferty, GD Lyon, AJ Savvas, N Weatherall, JH Williams, JC Farbin, A Jawahery, A Lillard, V Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Koptchev, VB Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Palombo, F Bauer, JM Cremaldi, L Eschenburg, V Kroeger, R Reidy, J Sanders, DA Summers, DJ Hast, C Taras, P Nicholson, H Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, P Piccolo, D Sciacca, C LoSecco, JM Alsmiller, JRG Gabriel, TA Brau, J Frey, R Iwasaki, M Potter, CT Sinev, NB Strom, D Torrence, E Colecchia, F Dorigo, A Galeazzi, F Margoni, M Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Voci, C Benayoun, M Briand, H Chauveau, J David, P de la Vaissiere, C Del Buono, L Hamon, O Leruste, P Ocariz, J Pivk, M Roos, L Stark, J Manfredi, PF Re, V Speziali, V Gladney, L Guo, QH Panetta, J Angelini, C Batignani, G Bettarini, S Bondioli, M Bucci, F Calderini, G Campagna, E Carpinelli, M Forti, F Giorgi, MA Lusiani, A Marchiori, G Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Danielson, N Elmer, P Lu, C Miftakov, V Olsen, J Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Bellini, F Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Wagner, G Waldi, R Adye, T De Groot, N Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R Emery, S Gaidot, A Giraud, PF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Schott, G Serfass, B Vasseur, G Yeche, C Zito, M Purohit, MV Weidemann, AW Yumiceva, FX Adam, I Aston, D Berger, N Boyarski, AM Convery, MR Coupal, DP Dong, D Dorfan, J Dunwoodie, W Field, RC Glanzman, T Gowdy, SJ Grauges, E Haas, T Hadig, T Halyo, V Himel, T Hryn'ova, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Muller, DR O'Grady, CP Ozcan, VE Perazzo, A Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Roodman, A Salnikov, AA Schietinger, T Schindler, RH Schwiening, J Simi, G Snyder, A Soha, A Spanier, SM Stelzer, J Su, D Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weaver, M Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, PR Cheng, CH Meyer, TI Roat, C Henderson, R Bugg, W Cohn, H Izen, JM Kitayama, I Lou, XC Bianchi, F Bona, M Gamba, D Bosisio, L Della Ricca, G Dittongo, S Lanceri, L Poropat, P Vitale, L Vuagnin, G Panvini, RS Banerjee, SW Brown, CM Fortin, D Jackson, PD Kowalewski, R Roney, JM Band, HR Dasu, S Datta, M Eichenbaum, AM Hu, H Johnson, JR Liu, R Di Lodovico, F Mohapatra, A Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, J Wu, SL Yu, Z Neal, H AF Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Zghiche, A Palano, A Pompili, A Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Ofte, I Stugu, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Charles, E Gill, MS Gritsan, AV Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kolomensky, YG Kral, JF LeClerc, C Levi, ME Lynch, G Mir, LM Oddone, PJ Orimoto, TJ Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Harrison, TJ Hawkes, CM Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Lewandowski, B Peters, K Schmuecker, H Steinke, M Barlow, NR Bhimji, W Boyd, JT Chevalier, N Clark, PJ Cottingham, WN Mackay, C Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Blinov, VE Bukin, AD Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AP Serednyakov, SI Skovpen, YI Yushkov, AN Best, D Chao, M Kirkby, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DP Buchanan, C Chun, S Hadavand, HK Hill, EJ MacFarlane, DB Paar, H Prell, S Rahatlou, S Raven, G Schwanke, U Sharma, V Berryhill, JW Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Mazur, MA Richman, JD Verkerke, W Beringer, J Eisner, AM Grothe, M Heusch, CA Lockman, WS Pulliam, T Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GP Dvoretskii, A Hitlin, DG Porter, FC Ryd, A Samuel, A Yang, S Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Ford, WT Nauenberg, U Olivas, A Rankin, P Roy, J Smith, JG van Hoek, WC Zhang, L Harton, JL Hu, T Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Altenburg, D Brandt, T Brose, J Colberg, T Dickopp, M Dubitzky, RS Hauke, A Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Lavin, D Muheim, F Playfer, S Swain, JE Tinslay, J Falbo, M Borean, C Bozzi, C Piemontese, L Sarti, A Treadwell, E Anulli, F Baldini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Lo Vetere, M Macri, M Monge, MR Passaggio, S Pastore, FC Patrignani, C Robutti, E Santroni, A Tosi, S Bailey, S Morii, M Bartoldus, R Grenier, GJ Mallik, U Cochran, J Crawley, HB Lamsa, J Meyer, WT Rosenberg, EI Yi, J Davier, M Grosdidier, G Hocker, A Lacker, HM Laplace, S Le Diberder, F Lepeltier, V Lutz, AM Petersen, TC Plaszczynski, S Schune, MH Tantot, L Trincaz-Duvoid, S Wormser, G Bionta, RM Brigljevic, V Lange, DJ van Bibber, K Wright, DM Bevan, AJ Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Morton, GW Nash, JA Sanders, P Smith, D Taylor, GP Back, JJ Bellodi, G Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Cowan, G Flaecher, HU George, S Green, MG Kurup, A Marker, CE McMahon, TR Ricciardi, S Salvatore, F Vaitsas, G Winter, MA Brown, D Davis, CL Allison, J Barlow, RJ Forti, AC Jackson, F Lafferty, GD Lyon, AJ Savvas, N Weatherall, JH Williams, JC Farbin, A Jawahery, A Lillard, V Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Koptchev, VB Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Palombo, F Bauer, JM Cremaldi, L Eschenburg, V Kroeger, R Reidy, J Sanders, DA Summers, DJ Hast, C Taras, P Nicholson, H Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, P Piccolo, D Sciacca, C LoSecco, JM Alsmiller, JRG Gabriel, TA Brau, J Frey, R Iwasaki, M Potter, CT Sinev, NB Strom, D Torrence, E Colecchia, F Dorigo, A Galeazzi, F Margoni, M Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Voci, C Benayoun, M Briand, H Chauveau, J David, P de la Vaissiere, C Del Buono, L Hamon, O Leruste, P Ocariz, J Pivk, M Roos, L Stark, J Manfredi, PF Re, V Speziali, V Gladney, L Guo, QH Panetta, J Angelini, C Batignani, G Bettarini, S Bondioli, M Bucci, F Calderini, G Campagna, E Carpinelli, M Forti, F Giorgi, MA Lusiani, A Marchiori, G Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Danielson, N Elmer, P Lu, C Miftakov, V Olsen, J Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Bellini, F Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Wagner, G Waldi, R Adye, T De Groot, N Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R Emery, S Gaidot, A Giraud, PF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Schott, G Serfass, B Vasseur, G Yeche, C Zito, M Purohit, MV Weidemann, AW Yumiceva, FX Adam, I Aston, D Berger, N Boyarski, AM Convery, MR Coupal, DP Dong, D Dorfan, J Dunwoodie, W Field, RC Glanzman, T Gowdy, SJ Grauges, E Haas, T Hadig, T Halyo, V Himel, T Hryn'ova, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Muller, DR O'Grady, CP Ozcan, VE Perazzo, A Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Roodman, A Salnikov, AA Schietinger, T Schindler, RH Schwiening, J Simi, G Snyder, A Soha, A Spanier, SM Stelzer, J Su, D Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weaver, M Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, PR Cheng, CH Meyer, TI Roat, C Henderson, R Bugg, W Cohn, H Izen, JM Kitayama, I Lou, XC Bianchi, F Bona, M Gamba, D Bosisio, L Della Ricca, G Dittongo, S Lanceri, L Poropat, P Vitale, L Vuagnin, G Panvini, RS Banerjee, SW Brown, CM Fortin, D Jackson, PD Kowalewski, R Roney, JM Band, HR Dasu, S Datta, M Eichenbaum, AM Hu, H Johnson, JR Liu, R Di Lodovico, F Mohapatra, A Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, J Wu, SL Yu, Z Neal, H CA BABAR Collaboration TI Measurements of branching fractions and CP-violating asymmetries in B-0 ->pi(+)pi(-), K+ pi(-), K+K- decays SO PHYSICAL REVIEW LETTERS LA English DT Article AB We present measurements of branching fractions and CP-violating asymmetries for two-body neutral (B) over bar meson decays to charged pions and kaons based on a sample of about 88x10(6) Y(4S)-->B (B) over bar decays. From a time-independent fit we measure the charge-averaged branching fractions B(B-0-->pi(+)pi(-))=(4.7+/-0.6+/-0.2)x10(-6), B(B-0-->K(+)pi(-))=(17.9+/-0.9+/-0.7)x10(-6), and the direct CP-violating charge asymmetry A(Kpi)=-0.102+/-0.050+/-0.016 [-0.188,-0.016], where the ranges in square brackets indicate the 90% confidence intervals. From a time-dependent fit we measure the B-0-->pi(+)pi(-) CP-violating parameters S-pipi=0.02+/-0.34+/-0.05 [-0.54,+0.58] and C-pipi=-0.30+/-0.25+/-0.04 [-0.72,+0.12]. C1 Phys Particules Lab, F-74941 Annecy Le Vieux, France. Univ Bari, Dipartmento Fis, I-70126 Bari, Italy. Ist Nazl Fis Nucl, I-70126 Bari, Italy. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Bergen, Inst Phys, N-5007 Bergen, Norway. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Ruhr Univ Bochum, Inst Expt Phys 1, D-44780 Bochum, Germany. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ British Columbia, Vancouver, BC V6T 1Z1, Canada. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. CALTECH, Pasadena, CA 91125 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Colorado, Boulder, CO 80309 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Tech Univ Dresden, Inst Kern & Teilchenphys, D-01062 Dresden, Germany. Ecole Polytech, LLR, F-91128 Palaiseau, France. Univ Edinburgh, Edinburgh EH9 3JZ, Midlothian, Scotland. Elon Univ, Elon, NC 27244 USA. Univ Ferrara, Dipartmento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, I-44100 Ferrara, Italy. Florida A&M Univ, Tallahassee, FL 32307 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy. Ist Nazl Fis Nucl, I-16146 Genoa, Italy. Harvard Univ, Cambridge, MA 02138 USA. Univ Iowa, Iowa City, IA 52242 USA. Iowa State Univ, Ames, IA 50011 USA. Lab Accelerateur Lineaire, F-91898 Orsay, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Univ London Imperial Coll Sci Technol & Med, London SW7 2BW, England. Queen Mary Univ London, London E1 4NS, England. Univ London Royal Holloway & Bedford New Coll, Egham TW20 0EX, Surrey, England. Univ Louisville, Louisville, KY 40292 USA. Univ Manchester, Manchester M13 9PL, Lancs, England. Univ Maryland, College Pk, MD 20742 USA. Univ Massachusetts, Amherst, MA 01003 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Mississippi, University, MS 38677 USA. Univ Montreal, Lab Rene JA Levesque, Montreal, PQ H3C 3J7, Canada. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Naples Federico II, Dipartimento Sci Fisiche, I-80126 Naples, Italy. Ist Nazl Fis Nucl, I-80126 Naples, Italy. Univ Notre Dame, Notre Dame, IN 46556 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Paris 06 & 07, Lab Phys Nucl HE, F-75252 Paris, France. Univ Pavia, Dipartimento Elettron, I-27100 Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Scuola Normale Super Pisa, I-56010 Pisa, Italy. Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Prairie View A&M Univ, Prairie View, TX 77446 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Rostock, D-18051 Rostock, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CEA Saclay, DAPNIA, F-91191 Gif Sur Yvette, France. Univ S Carolina, Columbia, SC 29208 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Stanford, CA 94305 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Tennessee, Knoxville, TN 37996 USA. Univ Texas, Richardson, TX 75083 USA. Univ Turin, Dipartimento Fis Sperimentale, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Victoria, Victoria, BC V8W 3P6, Canada. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. Univ Perugia, I-06100 Perugia, Italy. RP Aubert, B (reprint author), Phys Particules Lab, F-74941 Annecy Le Vieux, France. RI Cavallo, Nicola/F-8913-2012; Roe, Natalie/A-8798-2012; Peters, Klaus/C-2728-2008; de Groot, Nicolo/A-2675-2009; Lista, Luca/C-5719-2008; Bellini, Fabio/D-1055-2009; Schaffner, Stephen/D-1189-2011; Neri, Nicola/G-3991-2012; Forti, Francesco/H-3035-2011; Rotondo, Marcello/I-6043-2012; de Sangro, Riccardo/J-2901-2012; Bagnasco, Stefano/J-4324-2012; Sarti, Alessio/I-2833-2012; Patrignani, Claudia/C-5223-2009; Monge, Maria Roberta/G-9127-2012; Kravchenko, Evgeniy/F-5457-2015; Mir, Lluisa-Maria/G-7212-2015; Martinez Vidal, F*/L-7563-2014; Kolomensky, Yury/I-3510-2015; Lo Vetere, Maurizio/J-5049-2012; Lusiani, Alberto/N-2976-2015; Lusiani, Alberto/A-3329-2016; Morandin, Mauro/A-3308-2016; Della Ricca, Giuseppe/B-6826-2013; Di Lodovico, Francesca/L-9109-2016; Calcaterra, Alessandro/P-5260-2015; Frey, Raymond/E-2830-2016 OI Peters, Klaus/0000-0001-7133-0662; Bellini, Fabio/0000-0002-2936-660X; Neri, Nicola/0000-0002-6106-3756; Forti, Francesco/0000-0001-6535-7965; Rotondo, Marcello/0000-0001-5704-6163; de Sangro, Riccardo/0000-0002-3808-5455; Sarti, Alessio/0000-0001-5419-7951; Patrignani, Claudia/0000-0002-5882-1747; Monge, Maria Roberta/0000-0003-1633-3195; Mir, Lluisa-Maria/0000-0002-4276-715X; Martinez Vidal, F*/0000-0001-6841-6035; Kolomensky, Yury/0000-0001-8496-9975; Lo Vetere, Maurizio/0000-0002-6520-4480; Lusiani, Alberto/0000-0002-6876-3288; Lusiani, Alberto/0000-0002-6876-3288; Morandin, Mauro/0000-0003-4708-4240; Della Ricca, Giuseppe/0000-0003-2831-6982; Di Lodovico, Francesca/0000-0003-3952-2175; Calcaterra, Alessandro/0000-0003-2670-4826; Frey, Raymond/0000-0003-0341-2636 NR 25 TC 137 Z9 136 U1 0 U2 22 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 DEC 31 PY 2002 VL 89 IS 28 AR 281802 DI 10.1103/PhysRevLett.89.281802 PG 7 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900009 PM 12513134 ER PT J AU Frenkel, AI Kolobov, AV Robinson, IK Cross, JO Maeda, Y Bouldin, CE AF Frenkel, AI Kolobov, AV Robinson, IK Cross, JO Maeda, Y Bouldin, CE TI Direct separation of short range order in intermixed nanocrystalline and amorphous phases SO PHYSICAL REVIEW LETTERS LA English DT Article ID ABSORPTION FINE-STRUCTURE; GE; SCATTERING; SIO2; SPECTRA; FILMS AB Diffraction anomalous fine-structure (DAFS) and extended x-ray absorption fine-structure (EXAFS) measurements were combined to determine short range order (SRO) about a single atomic type in a sample of mixed amorphous and nanocrystalline phases of germanium. EXAFS yields information about the SRO of all Ge atoms in the sample, while DAFS determines the SRO of only the ordered fraction. We determine that the first-shell distance distribution is bimodal; the nanocrystalline distance is the same as the bulk crystal, to within 0.01(2) Angstrom, but the mean amorphous Ge-Ge bond length is expanded by 0.076(19) Angstrom. This approach can be applied to many systems of mixed amorphous and nanocrystalline phases. C1 Yeshiva Univ, Dept Phys, New York, NY 10016 USA. Natl Inst Adv Ind Sci & Technol, Joint Res Ctr Atom Technol, Tsukuba, Ibaraki 3058562, Japan. Natl Inst Adv Ind Sci & Technol, Lab Adv Opt Technol, Tsukuba, Ibaraki 3058562, Japan. Univ Illinois, Dept Phys, Loomis Lab, Urbana, IL 61801 USA. Argonne Natl Lab, PNCCAT, Argonne, IL 60439 USA. Univ Osaka Prefecture, Osaka 5998531, Japan. Natl Inst Stand & Technol, Div Ceram, Gaithersburg, MD 20899 USA. RP Frenkel, AI (reprint author), Yeshiva Univ, Dept Phys, New York, NY 10016 USA. RI Frenkel, Anatoly/D-3311-2011 OI Frenkel, Anatoly/0000-0002-5451-1207 NR 18 TC 31 Z9 31 U1 1 U2 7 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 DEC 31 PY 2002 VL 89 IS 28 AR 285503 DI 10.1103/PhysRevLett.89.285503 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900032 PM 12513157 ER PT J AU Habib, S Heitmann, K Jungman, G Molina-Paris, C AF Habib, S Heitmann, K Jungman, G Molina-Paris, C TI The inflationary perturbation spectrum SO PHYSICAL REVIEW LETTERS LA English DT Article ID DENSITY PERTURBATIONS; COSMOLOGICAL PERTURBATIONS; UNIVERSE; FLUCTUATIONS; RADIATION AB Motivated by the prospect of testing inflation from precision cosmic microwave background observations, we present analytic results for scalar and tensor perturbations in single-field inflation models, based on the application of uniform approximations. This technique is systematically improvable, possesses controlled error bounds, and does not rely on assuming the slow-roll parameters to be constant. We provide closed form expressions for the power spectra and the corresponding scalar and tensor spectral indices. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Warwick, Inst Math, Coventry CV4 7AL, W Midlands, England. RP Habib, S (reprint author), Los Alamos Natl Lab, Div Theoret, MS B285, Los Alamos, NM 87545 USA. NR 23 TC 48 Z9 48 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 31 PY 2002 VL 89 IS 28 AR 281301 DI 10.1103/PhysRevLett.89.281301 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900006 PM 12513131 ER PT J AU Holian, BL Germann, TC Maillet, JB White, CT AF Holian, BL Germann, TC Maillet, JB White, CT TI Atomistic mechanism for hot spot initiation SO PHYSICAL REVIEW LETTERS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS AB We propose a picture of the role of shock-wave interactions with microscopic voids that leads to significant heating, sufficient to thermally initiate chemical reactions in solid explosives, or phase transitions in metals. The key ingredients to this dramatic overshoot in temperature are: (i) a strong enough shock wave to cause vaporization of material into the void; (ii) the stagnation of low-density vapor (for a wide enough gap) at the far side; and (iii) recompression of the gas (pressure-volume work) from low density back to the original shocked density. We explore dependencies on both shock strength and one-dimensional gap width in atomistic simulations of a two-dimensional unreactive Lennard-Jones solid, comparing observed thermal overshoot with a straightforward model, to show how hot spots can be generated under shock-wave conditions. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Comml Energia Atom, F-91680 Bruyeres Le Chatel, France. USN, Res Lab, Washington, DC 20375 USA. RP Holian, BL (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 9 TC 54 Z9 61 U1 6 U2 31 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 31 PY 2002 VL 89 IS 28 AR 285501 DI 10.1103/PhysRevLett.89.285501 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900030 PM 12513155 ER PT J AU Jaime, M Kim, KH Jorge, G McCall, S Mydosh, JA AF Jaime, M Kim, KH Jorge, G McCall, S Mydosh, JA TI High magnetic field studies of the hidden order transition in URu2Si2 SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRON SUPERCONDUCTOR URU2SI2; FERMION SYSTEM URU2SI2; COMPOUND URU2SI2; SI-29 NMR; PRESSURE; EXCITATIONS; HEAT AB We studied in detail the low temperature/high magnetic field phases of URu2Si2 single crystals with specific heat, magnetocaloric effect, and magnetoresistance in magnetic fields up to 45 T. Data obtained down to 0.5 K, and extrapolated to T=0, show a suppression of the hidden-order phase at H-0(0)=35.9+/-0.35 T and the appearance of a new phase for magnetic fields in excess of H-1(0)=36.1+/-0.35 T observed only at temperatures lower than 6 K. In turn, complete suppression of this high field state is attained at a critical magnetic field H-2(0)=39.7+/-0.35 T. No phase transitions are observed above 40 T. We discuss our results in the context of itinerant versus localized f electrons. C1 Los Alamos Natl Lab, NHMFL, Los Alamos, NM 87545 USA. Univ Buenos Aires, Dept Fis, Buenos Aires, DF, Argentina. Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Leiden Univ, Kamerlingh Onnes Lab, NL-2300 RA Leiden, Netherlands. Max Planck Inst Chem Phys Solids, Dresden, Germany. RP Los Alamos Natl Lab, NHMFL, Los Alamos, NM 87545 USA. RI McCall, Scott/G-1733-2014; Jaime, Marcelo/F-3791-2015 OI McCall, Scott/0000-0002-7979-4944; Jaime, Marcelo/0000-0001-5360-5220 NR 34 TC 75 Z9 75 U1 5 U2 30 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 DEC 31 PY 2002 VL 89 IS 28 AR 287201 DI 10.1103/PhysRevLett.89.287201 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900050 PM 12513175 ER PT J AU Lauritsen, T Janssens, RVF Carpenter, MP Fallon, P Herskind, B Jenkins, DG Khoo, TL Kondev, FG Lopez-Martens, A Macchiavelli, AO Ward, D Abu Saleem, K Ahmad, I Clark, RM Cromaz, M Dossing, T Heinz, AM Korichi, A Lane, G Lister, CJ Seweryniak, D AF Lauritsen, T Janssens, RVF Carpenter, MP Fallon, P Herskind, B Jenkins, DG Khoo, TL Kondev, FG Lopez-Martens, A Macchiavelli, AO Ward, D Abu Saleem, K Ahmad, I Clark, RM Cromaz, M Dossing, T Heinz, AM Korichi, A Lane, G Lister, CJ Seweryniak, D TI Octupole vibration in superdeformed Dy-152(66)86 SO PHYSICAL REVIEW LETTERS LA English DT Article ID EXCITATION-ENERGIES; QUADRUPOLE-MOMENTS; EXCITED BANDS; LIFETIME MEASUREMENTS; ROTATIONAL BANDS; NUCLEI; STATES; HG-190; YRAST; SPINS AB Nine transitions of dipole character have been identified linking an excited superdeformed (SD) band in Dy-152 to the yrast SD band. As a result, the excitation energy of the lowest level in the excited SD band has been measured to be 14238 keV. This corresponds to a 1.3 MeV excitation above the SD ground state. The levels in this band have tentatively been determined to be of negative parity and odd spin. The measured properties are consistent with an interpretation in terms of a rotational band built on a collective octupole vibration. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Niels Bohr Inst, DK-2100 Copenhagen, Denmark. CNRS, IN2P3, CSNSM, F-91405 Orsay, France. RP Lauritsen, T (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Lane, Gregory/A-7570-2011; Heinz, Andreas/E-3191-2014; Carpenter, Michael/E-4287-2015 OI Lane, Gregory/0000-0003-2244-182X; Carpenter, Michael/0000-0002-3237-5734 NR 41 TC 30 Z9 30 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 31 PY 2002 VL 89 IS 28 AR 282501 DI 10.1103/PhysRevLett.89.282501 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900011 PM 12513136 ER PT J AU Lu, ZY Nicklaw, CJ Fleetwood, DM Schrimpf, RD Pantelides, ST AF Lu, ZY Nicklaw, CJ Fleetwood, DM Schrimpf, RD Pantelides, ST TI Structure, properties, and dynamics of oxygen vacancies in amorphous SiO2 SO PHYSICAL REVIEW LETTERS LA English DT Article ID INITIO MOLECULAR-DYNAMICS; HOLE ANNEALING PROCESS; BORDER TRAPS; SILICON DIOXIDE; VITREOUS SIO2; E' CENTER; OXIDE; DEFECTS; MODEL; MECHANISMS AB Oxygen vacancies in SiO2 have long been regarded as bistable, forming a Si-Si dimer when neutral and a puckered configuration when positively charged. We report first-principles calculations of O vacancies in amorphous SiO2 supercells that unveil significantly more complex behavior. We find that the vast majority of O vacancies do not pucker after capture of a hole, but are shallow traps. The remaining vacancies exhibit two distinct types of puckering. Upon capturing an electron, one type forms a metastable dipole, while the other collapses to a dimer. A statistical distribution of O vacancies is obtained, and the implications for charge transport and trapping in SiO2 are discussed. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Lu, ZY (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RI 上官, 敏慧/E-8964-2012; Schrimpf, Ronald/L-5549-2013 OI Schrimpf, Ronald/0000-0001-7419-2701 NR 30 TC 107 Z9 109 U1 1 U2 38 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 DEC 31 PY 2002 VL 89 IS 28 AR 285505 DI 10.1103/PhysRevLett.89.285505 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900034 PM 12513159 ER PT J AU Mahendiran, R Maignan, A Hebert, S Martin, C Hervieu, M Raveau, B Mitchell, JF Schiffer, P AF Mahendiran, R Maignan, A Hebert, S Martin, C Hervieu, M Raveau, B Mitchell, JF Schiffer, P TI Ultrasharp magnetization steps in perovskite manganites SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHASE-SEPARATION; DOPED MANGANITES; METAMAGNETISM; TRANSITIONS; CR; ANISOTROPY; METAL AB We report a detailed study of steplike metamagnetic transitions in polycrystalline Pr0.5Ca0.5Mn0.95Co0.05O3. The steps have a sudden onset below a critical temperature, are extremely sharp (width <2x10(-4) T), and occur at critical fields which are linearly dependent on the absolute value of the cooling field in which the sample is prepared. Similar transitions are also observed at low temperature in non-Co doped manganites, including single crystal samples. These data show that the steps are an intrinsic property, qualitatively different from either previously observed higher temperature metamagnetic transitions in the manganites or metamagnetic transitions observed in other materials. C1 Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Penn State Univ, Inst Mat Res, University Pk, PA 16802 USA. ISMRA Univ Caen, Lab CRISMAT, F-14050 Caen, France. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Mahendiran, R (reprint author), Penn State Univ, Dept Phys, 104 Davey Lab, University Pk, PA 16802 USA. RI Schiffer, Peter/F-3227-2011; Mahendiran, R/G-1123-2012 NR 30 TC 155 Z9 158 U1 0 U2 21 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 DEC 31 PY 2002 VL 89 IS 28 AR 286602 DI 10.1103/PhysRevLett.89.286602 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900044 PM 12513169 ER PT J AU Militzer, B Pollock, EL AF Militzer, B Pollock, EL TI Lowering of the kinetic energy in interacting quantum systems SO PHYSICAL REVIEW LETTERS LA English DT Article ID MOMENTUM DISTRIBUTION; EQUATION; STATE AB Interactions never lower the ground state kinetic energy of a quantum system below the noninteracting value. However, at nonzero temperature, where the system occupies a thermal distribution of states, interactions can reduce the kinetic energy. This can be demonstrated from a first order weak coupling expansion. Simulations (both variational and restricted path integral Monte Carlo) of the electron gas model and dense hydrogen confirm this and show that in contrast to the ground state case, at nonzero temperature the population of low momentum states can be increased relative to the free Fermi distribution. This effect is not seen in simulations of liquid He-3. C1 Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94550 USA. RP Militzer, B (reprint author), Lawrence Livermore Natl Lab, Dept Phys, Livermore, CA 94550 USA. NR 17 TC 10 Z9 10 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 31 PY 2002 VL 89 IS 28 AR 280401 DI 10.1103/PhysRevLett.89.280401 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900001 PM 12513126 ER PT J AU Zhu, JX Balatsky, AV AF Zhu, JX Balatsky, AV TI Quantum electronic transport through a precessing spin SO PHYSICAL REVIEW LETTERS LA English DT Article ID RESONANCE; SILICON; STM AB The conductance through a local nuclear spin precessing in a magnetic field is studied by using the equations-of-motion approach. The characteristics of the conductance is determined by the tunneling matrix and the position of equilibrium chemical potential. We find that the spin-flip coupling between the electrons on the spin site and the leads produces the conductance oscillation. When the spin is precessing in the magnetic field at Larmor frequency (omega(L)), the conductance develops the oscillation with the frequency of both omega(L) and 2omega(L) components, the relative spectrum weight of which can be tuned by the chemical potential and the spin-flip coupling. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Zhu, JX (reprint author), Los Alamos Natl Lab, Div Theoret, MS B262, Los Alamos, NM 87545 USA. NR 22 TC 37 Z9 38 U1 0 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 DEC 31 PY 2002 VL 89 IS 28 AR 286802 DI 10.1103/PhysRevLett.89.286802 PG 4 WC Physics, Multidisciplinary SC Physics GA 634AM UT WOS:000180317900046 PM 12513171 ER PT J AU Stump, BW Hedlin, MAH Pearson, DC Hsu, V AF Stump, BW Hedlin, MAH Pearson, DC Hsu, V TI Characterization of mining explosions at regional distances: Implications with the international monitoring system SO REVIEWS OF GEOPHYSICS LA English DT Review DE regional; monitoring; seismology; detection; location; characterization ID QUARRY BLASTS; CHEMICAL EXPLOSIONS; SEISMIC SIGNALS; UNITED-STATES; RG WAVES; EARTHQUAKES; DISCRIMINATION; IDENTIFICATION; PROPAGATION; PHASE AB [1] The International Monitoring System (IMS) being constructed in support of the Comprehensive Nuclear-Test-Ban Treaty introduces new opportunities to nuclear test monitoring by providing open access to global data from seismic, hydroacoustic, infrasonic, and radionuclide sensors. These sensors will detect myriad natural and man-made events and can be used to identify those that have explosive characteristics and therefore might be clandestine nuclear tests. Detection and identification of seismic events must be conducted at a lower magnitude threshold (m(b) = 3.5 and lower) than has been previously considered. Concomitant with the lower monitoring threshold will be an increased number of events that must be scrutinized. This collection will be largely composed of regional observations in which the seismic waves have traversed complex geological structures. High-fidelity regional, geophysical models will be needed to support accurate location and source identification. Source identification will not be limited to the separation of single-fired nuclear explosions from earthquakes as in previous testing treaties. The lower-magnitude threshold and increased reliance on regional observations assures that mining explosions will be detected by the monitoring system. It is important that the signals from mining explosions are properly identified to avoid false alarms of the monitoring system. Cooperation with the mining industry, including deployment of close-in instrumentation and extensive documentation of the explosions, provides critical information for interpreting the performance of regional discriminants. Linkage of these observations to appropriate physical models of the blasting process is also enhanced through this cooperative research effort. A number of discriminants for characterizing mining explosions have been identified including P to L(g) ratios at high and low frequencies, surface wave to high-frequency body wave amplitudes, R(g) at short distances, high- and low-frequency time-independent spectral modulations, signal correlation, and temporal clustering. Variable performance of individual discriminants results from such factors as mine-specific blasting practices and the complexity of the regional wave propagation. This variability attests to the need for a suite of region-specific discriminants. Regional calibration with modest-size, single-fired contained chemical explosions can provide a basis for developing region-specific procedures. Broadband data provide the basis for the most robust set of discriminants. The inclusion of infrasonic data as part of the IMS introduces a potential for the combined use of seismic and infrasonic data for the identification of near-surface explosions. The generation and, to a greater extent, the propagation of mining explosion infrasonic signals is not well understood, but empirical data attest to its future utility. Evidence for the accidental, near-simultaneous detonation of a large amount of explosives during standard delay-fired explosions is presented. Events such as these have single-fired characteristics and may prove to be problematic in discrimination analysis. C1 So Methodist Univ, Dept Geol Sci, Dallas, TX 75275 USA. Univ Calif San Diego, Inst Geophys & Planetary Phys, La Jolla, CA 92093 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. AF Tech Applicat Ctr, Patrick AFB, FL 32925 USA. RP Stump, BW (reprint author), So Methodist Univ, Dept Geol Sci, POB 750395, Dallas, TX 75275 USA. EM stump@passion.isem.smu.edu; hedlin@epicenter.ucsd.edu; cpearson@lanl.gov; vindell@tt.aftac.gov NR 91 TC 16 Z9 16 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 8755-1209 J9 REV GEOPHYS JI Rev. Geophys. PD DEC 31 PY 2002 VL 40 IS 4 AR 1011 DI 10.1029/1998RG000048 PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 649MX UT WOS:000181213500001 ER PT J AU Scanlon, BR Christman, M Reedy, RC Porro, I Simunek, J Flerchinger, GN AF Scanlon, BR Christman, M Reedy, RC Porro, I Simunek, J Flerchinger, GN TI Intercode comparisons for simulating water balance of surficial sediments in semiarid regions SO WATER RESOURCES RESEARCH LA English DT Article DE hydrologic budget; soil moisture; unsaturated zone; water balance modeling ID SOIL HYDRAULIC-PROPERTIES; CHARACTERISTIC CURVE; UNSATURATED SOILS; DAILY RAINFALL; MODEL; CONDUCTIVITY; RETENTION; ZONE; DISAGGREGATION; TEMPERATURE AB Near-surface water balance modeling is often used to evaluate land-atmosphere interactions, deep drainage, and groundwater recharge. The purpose of this study was to compare water balance simulation results from seven different codes, HELP, HYDRUS-1D, SHAW, SoilCover, SWIM, UNSAT-H, and VS2DTI, using 1-3 year water balance monitoring data from nonvegetated engineered covers (3 m deep) in warm (Texas) and cold (Idaho) desert regions. Simulation results from most codes were similar and reasonably approximated measured water balance components. Simulation of infiltration-excess runoff was a problem for all codes. Annual drainage was estimated to within +/-64% by most codes. Outliers result from the modeling approach (storage routing versus Richards' equation), upper boundary condition during precipitation, lower boundary condition (seepage face versus unit gradient), and water retention function (van Genuchten versus Brooks and Corey). A unique aspect of the code comparison study was the ability to explain the outliers by incorporating the simulation approaches (boundary conditions or hydraulic parameters) used in the outlying codes in a single code and comparing the results of the modified and unmodified code. This approach overcomes the criticism that valid code comparisons are infeasible because of large numbers of differences among codes. The code comparison study identified important factors for simulating the near-surface water balance. C1 Univ Texas, Bur Econ Geol, Austin, TX 78758 USA. Geosyntec Consultants, Austin, TX 78701 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. George E Brown Jr Salin Lab, Riverside, CA 92507 USA. ARS, USDA, REE, PWA,WMR, Boise, ID 83712 USA. RP Scanlon, BR (reprint author), Univ Texas, Bur Econ Geol, 10100 Burnet Rd, Austin, TX 78758 USA. RI Simunek, Jiri/F-3196-2011; Scanlon, Bridget/A-3105-2009 OI Scanlon, Bridget/0000-0002-1234-4199 NR 71 TC 64 Z9 66 U1 3 U2 29 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 31 PY 2002 VL 38 IS 12 AR 1323 DI 10.1029/2001WR001233 PG 16 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 650ET UT WOS:000181250400003 ER PT J AU Hwang, JH Schaff, WJ Eastman, LF Bradley, ST Brillson, LJ Look, DC Wu, J Walukiewicz, W Furis, M Cartwright, AN AF Hwang, JH Schaff, WJ Eastman, LF Bradley, ST Brillson, LJ Look, DC Wu, J Walukiewicz, W Furis, M Cartwright, AN TI Si doping of high-Al-mole fraction AlxGa1-xN alloys with rf plasma-induced molecular-beam-epitaxy SO APPLIED PHYSICS LETTERS LA English DT Article ID GAN; ALGAN; ACCEPTOR; DONOR AB Very high levels of n-type doping of AlxGa1-xN alloys were recently achieved by rf plasma-induced molecular-beam epitaxy on sapphire substrates and Si as a do-pant. Electron concentrations were obtained up to 1.25 x 10(20) cm(-3) when the Al mole fraction was 50%, and 8.5 x 10(19) cm(-3) electrons were measured even when the Al mole fraction was 80%. Other material properties were determined by optical absorption, photoluminescence, cathodoluminescence, x-ray diffraction, and atomic force microscopy measurements and high optical and morphological qualities were shown. (C) 2002 American Institute of Physics. [DOI: 10.1063/1.1534395]. C1 Cornell Univ, Dept Elect & Comp Engn, Ithaca, NY 14853 USA. Ohio State Univ, Dept Elect Engn, Columbus, OH 43210 USA. Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. SUNY Buffalo, Dept Elect Engn, Buffalo, NY 14260 USA. RP Hwang, JH (reprint author), Cornell Univ, Dept Elect & Comp Engn, Ithaca, NY 14853 USA. RI Wu, Junqiao/G-7840-2011; Cartwright, Alexander/C-4380-2008; Furis, Madalina/F-8090-2015 OI Wu, Junqiao/0000-0002-1498-0148; Cartwright, Alexander/0000-0002-0921-8036; Furis, Madalina/0000-0001-9007-5492 NR 17 TC 22 Z9 23 U1 0 U2 9 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 30 PY 2002 VL 81 IS 27 BP 5192 EP 5194 DI 10.1063/1.1534395 PG 3 WC Physics, Applied SC Physics GA 631GY UT WOS:000180160800032 ER PT J AU Kalinin, SV Bonnell, DA Freitag, M Johnson, AT AF Kalinin, SV Bonnell, DA Freitag, M Johnson, AT TI Tip-gating effect in scanning impedance microscopy of nanoelectronic devices SO APPLIED PHYSICS LETTERS LA English DT Article ID FORCE MICROSCOPY; PROBE MICROSCOPY; CARBON NANOTUBES; TRANSISTORS AB Electronic transport in semiconducting single-walled carbon nanotubes is studied by combined scanning gate microscopy and scanning impedance microscopy (SIM). Depending on the probe potential, SIM can be performed in both invasive and noninvasive modes. High-resolution imaging of the defects is achieved when the probe acts as a local gate and simultaneously as an electrostatic probe of local potential. A class of weak defects becomes observable even if they are located in the vicinity of strong defects. The imaging mechanism of tip-gating scanning impedance microscopy is discussed. (C) 2002 American Institute of Physics. [DOI: 10.1063/.1.1531833]. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Univ Penn, Res Struct Matter Lab, Philadelphia, PA 19104 USA. RP Bonnell, DA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Kalinin, Sergei/I-9096-2012 OI Kalinin, Sergei/0000-0001-5354-6152 NR 12 TC 27 Z9 27 U1 0 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 DEC 30 PY 2002 VL 81 IS 27 BP 5219 EP 5221 DI 10.1063/1.1531833 PG 3 WC Physics, Applied SC Physics GA 631GY UT WOS:000180160800041 ER PT J AU Meunier, V Nardelli, MB Bernholc, J Zacharia, T Charlier, JC AF Meunier, V Nardelli, MB Bernholc, J Zacharia, T Charlier, JC TI Intrinsic electron transport properties of carbon nanotube Y-junctions SO APPLIED PHYSICS LETTERS LA English DT Article ID HETEROJUNCTIONS; RECTIFICATION; CONDUCTANCE; DEVICES; SINGLE AB The electron transport properties of three-terminal carbon-nanotube junctions are investigated within the Landauer theory of quantum conductance. Using a realistic tight-binding Hamiltonian, we demonstrate that the experimentally observed rectifying behavior is not an intrinsic property of the junction, but rather of the contact geometry. When semiconducting nanotubes are connected to metallic leads, nontransmitting states are induced at the nanotube-metal interface, leading to asymmetric transmission curves and potentially rectifying behavior of the nanodevice. (C) 2002 American Institute of Physics. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Oak Ridge Natl Lab, Comp & Computat Sci Directorate, Oak Ridge, TN 37831 USA. Univ Catholique Louvain, PCPM, B-1348 Louvain, Belgium. Univ Catholique Louvain, CERMIN, B-1348 Louvain, Belgium. RP Meunier, V (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RI Buongiorno Nardelli, Marco/C-9089-2009; Meunier, Vincent/F-9391-2010; OI Meunier, Vincent/0000-0002-7013-179X; Zacharia, Thomas/0000-0001-6463-5425 NR 35 TC 61 Z9 61 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 DEC 30 PY 2002 VL 81 IS 27 BP 5234 EP 5236 DI 10.1063/1.1533842 PG 3 WC Physics, Applied SC Physics GA 631GY UT WOS:000180160800046 ER PT J AU Acharya, BR Baldwin, KW MacHarrie, RA Rogers, JA Huang, CC Pindak, R AF Acharya, BR Baldwin, KW MacHarrie, RA Rogers, JA Huang, CC Pindak, R TI In-fiber nematic liquid crystal optical modulator based on in-plane switching with microsecond response time SO APPLIED PHYSICS LETTERS LA English DT Article ID MODE AB We describe a simple method and device design that enables fast in-plane electro-optic modulation in conventional nematic liquid crystal. (NLC).,devices. When combined with optimized NLC materials, this approach yields rotational speeds of 1degrees/mus (independent of rotation angle, over a wide range) at a moderately low voltage. The observed rotational dynamics indicate that even these high speeds may not represent fundamental physical limits. We demonstrate these ideas in a compact tunable. NLC waveplate that uses microelectrodes patterned directly on the tips of optical fibers. These devices offer fast, continuously tunable optic axis with low insertion loss and good performance in the near infrared. Modulators that use this design have promising potential applications for polarization control and analysis in optical communication systems. (C) 2002 American Institute of Physics. C1 Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Univ Minnesota, Dept Phys & Astron, Minneapolis, MN 55455 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Acharya, BR (reprint author), Bell Labs, Lucent Technol, 600 Mt Ave, Murray Hill, NJ 07974 USA. NR 11 TC 28 Z9 28 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 DEC 30 PY 2002 VL 81 IS 27 BP 5243 EP 5245 DI 10.1063/1.1532532 PG 3 WC Physics, Applied SC Physics GA 631GY UT WOS:000180160800049 ER PT J AU Shan, XP Ellern, A Espenson, JH AF Shan, XP Ellern, A Espenson, JH TI Methyloxorhenium(V) complexes with two bidentate ligands: Syntheses and reactivity studies SO INORGANIC CHEMISTRY LA English DT Article ID RHENIUM-CATALYZED OXIDATION; OXYGEN-ATOM TRANSFER; STRUCTURAL CHARACTERIZATION; PHOSPHINE-LIGANDS; CRYSTAL-STRUCTURE; NUCLEAR-MEDICINE; KINETICS; MONOMERIZATION; SULFOXIDE; OXIDES AB Four new methyloxorhenium(V) complexes were synthesized: MeReO(PA)(2) (1), MeReO(HQ)(2) (2), MeReO(MQ)(2) (3), and MeReO(diphenylphosphinobenzoate)(2) (4) (in which PAH = 2-picolinic acid, HQH = 8-hydroxyquinoline, and MQH = 8-mercaptoquinoline). Although only one geometric structure has been identified crystallographically for 1, 2, and 3, two isomers of 3 and 4 in solution were detected by NMR spectroscopy. These compounds catalyze the sulfoxidation of thioethers by pyridine N-oxides and sulfoxides. The rate law for the reaction between pyridine N-oxides and thioethers, catalyzed by 1, shows a first-order dependence on the concentrations of pyridine N-oxide and 1. The second-order rate constants of a series of para-substituted pyridine N-oxides fall in the range of 0.27-7.5 L mol(-1) s(-1). Correlation of these rate constants by the Hammett LFER method gave a large negative reaction constant, p = -5.2. The next and rapid step does not influence the kinetics, but it could be explored with competition experiments carried out with a pair of methyl aryl sulfides, MeSC6H4-p-Y. The value of each rate was expressed relative to the reference compound that has Y = H. A Hammett analysis of k(Y)/k(H) gave p = -1.9. Oxygen-18 labeled 1 was used in a single turnover experiment for 4-picoline N-oxide and dimethyl sulfide. No O-18-labeled DMSO was found. We suggest that the reaction proceeds by way of two intermediates that were not observed during the reaction. The first intermediate contains an opened PA-chelate ring; this allows the pyridine N-oxide to access the primary coordination sphere of rhenium. The second intermediate is a cis-dioxorhenium(VII) species, which the thioether then attacks. Oxygen-18 experiments were used to show that the two oxygens of this intermediate are not equivalent; only the new oxygen is attacked by, and transferred to, SR2. Water inhibits the reaction because it hydrolyzes the rhenium(VII) intermediate. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 47 TC 22 Z9 22 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 30 PY 2002 VL 41 IS 26 BP 7136 EP 7142 DI 10.1021/ic025952f PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 630HX UT WOS:000180102400029 PM 12495355 ER PT J AU Adler, C Ahammed, Z Allgower, C Amonett, J Anderson, BD Anderson, M Averichev, GS Balewski, J Barannikova, O Barnby, LS Baudot, J Bekele, S Belaga, VV Bellwied, R Berger, J Bichsel, H Bland, LC Blyth, CO Bonner, BE Boucham, A Brandin, A Bravar, A Cadman, RV Caines, H Sanchez, MCD Cardenas, A Carroll, J Castillo, J Castro, M Cebra, D Chaloupka, P Chattopadhyay, S Chen, Y Chernenko, SP Cherney, M Chikanian, A Choi, B Christie, W Coffin, JP Cormier, TM Cramer, JG Crawford, HJ Deng, WS Derevschikov, AA Didenko, L Dietel, T Draper, JE Dunin, VB Dunlop, JC Eckardt, V Efimov, LG Emelianov, V Engelage, J Eppley, G Erazmus, B Fachini, P Faine, V Filimonov, K Finch, E Fisyak, Y Flierl, D Foley, KJ Fu, J Gagliardi, CA Gagunashvili, N Gans, J Gaudichet, L Germain, M Geurts, F Ghazikhanian, V Grachov, O Grigoriev, V Guedon, M Gushin, E Hallman, TJ Hardtke, D Harris, JW Henry, TW Heppelmann, S Herston, T Hippolyte, B Hirsch, A Hjort, E Hoffmann, GW Horsley, M Huang, HZ Humanic, TJ Igo, G Ishihara, A Ivanshin, YI Jacobs, P Jacobs, WW Janik, M Johnson, I Jones, PG Judd, EG Kaneta, M Kaplan, M Keane, D Kiryluk, J Kisiel, A Klay, J Klein, SR Klyachko, A Konstantinov, AS Kopytine, M Kotchenda, L Kovalenko, AD Kramer, M Kravtsov, P Krueger, K Kuhn, C Kulikov, AI Kunde, GJ Kunz, CL Kutuev, RK Kuznetsov, AA Lakehal-Ayat, L Lamont, MAC Landgraf, JM Lange, S Lansdell, CP Lasiuk, B Laue, F Lebedev, A Lednicky, R Leontiev, VM LeVine, MJ Li, Q Lindenbaum, SJ Lisa, MA Liu, F Liu, L Liu, Z Liu, QJ Ljubicic, T Llope, WJ LoCurto, G Long, H Longacre, RS Lopez-Noriega, M Love, WA Ludlam, T Lynn, D Ma, J Majka, R Margetis, S Markert, C Martin, L Marx, J Matis, HS Matulenko, YA McShane, TS Meissner, F Melnick, Y Meschanin, A Messer, M Miller, ML Milosevich, Z Minaev, NG Mitchell, J Moiseenko, VA Moore, CF Morozov, V de Moura, MM Munhoz, MG Nelson, JM Nevski, P Nikitin, VA Nogach, LV Norman, B Nurushev, SB Nystrand, J Odyniec, G Ogawa, A Okorokov, V Oldenburg, M Olson, D Paic, G Pandey, SU Panebratsev, Y Panitkin, SY Pavlinov, AI Pawlak, T Perevoztchikov, V Peryt, W Petrov, VA Planinic, M Pluta, J Porile, N Porter, J Poskanzer, AM Potrebenikova, E Prindle, D Pruneau, C Putschke, J Rai, G Rakness, G Ravel, O Ray, RL Razin, SV Reichhold, D Reid, JG Retiere, F Ridiger, A Ritter, HG Roberts, JB Rogachevski, OV Romero, JL Roy, C Rykov, V Sakrejda, I Salur, S Sandweiss, J Saulys, AC Savin, I Schambach, J Scharenberg, RP Schmitz, N Schroeder, LS Schuttauf, A Schweda, K Seger, J Seliverstov, D Seyboth, P Shahaliev, E Shestermanov, KE Shimanskii, SS Shvetcov, VS Skoro, G Smirnov, N Snellings, R Sorensen, P Sowinski, J Spinka, HM Srivastava, B Stephenson, EJ Stock, R Stolpovsky, A Strikhanov, M Stringfellow, B Struck, C Suaide, AAP Sugarbaker, E Suire, C Sumbera, M Surrow, B Symons, TJM de Toledo, AS Szarwas, P Tai, A Takahashi, J Tang, AH Thomas, JH Thompson, M Tikhomirov, V Tokarev, M Tonjes, MB Trainor, TA Trentalange, S Tribble, RE Trofimov, V Tsai, O Ullrich, T Underwood, DG Van Buren, G VanderMolen, AM Vasilevski, IM Vasiliev, AN Vigdor, SE Voloshin, SA Wang, F Ward, H Watson, JW Wells, R Westfall, GD Whitten, C Wieman, H Willson, R Wissink, SW Witt, R Wood, J Xu, N Xu, Z Yakutin, AE Yamamoto, E Yang, J Yepes, P Yurevich, VI Zanevski, YV Zborovsky, I Zhang, H Zhang, WM Zoulkarneev, R Zubarev, AN AF Adler, C Ahammed, Z Allgower, C Amonett, J Anderson, BD Anderson, M Averichev, GS Balewski, J Barannikova, O Barnby, LS Baudot, J Bekele, S Belaga, VV Bellwied, R Berger, J Bichsel, H Bland, LC Blyth, CO Bonner, BE Boucham, A Brandin, A Bravar, A Cadman, RV Caines, H Sanchez, MCD Cardenas, A Carroll, J Castillo, J Castro, M Cebra, D Chaloupka, P Chattopadhyay, S Chen, Y Chernenko, SP Cherney, M Chikanian, A Choi, B Christie, W Coffin, JP Cormier, TM Cramer, JG Crawford, HJ Deng, WS Derevschikov, AA Didenko, L Dietel, T Draper, JE Dunin, VB Dunlop, JC Eckardt, V Efimov, LG Emelianov, V Engelage, J Eppley, G Erazmus, B Fachini, P Faine, V Filimonov, K Finch, E Fisyak, Y Flierl, D Foley, KJ Fu, J Gagliardi, CA Gagunashvili, N Gans, J Gaudichet, L Germain, M Geurts, F Ghazikhanian, V Grachov, O Grigoriev, V Guedon, M Gushin, E Hallman, TJ Hardtke, D Harris, JW Henry, TW Heppelmann, S Herston, T Hippolyte, B Hirsch, A Hjort, E Hoffmann, GW Horsley, M Huang, HZ Humanic, TJ Igo, G Ishihara, A Ivanshin, YI Jacobs, P Jacobs, WW Janik, M Johnson, I Jones, PG Judd, EG Kaneta, M Kaplan, M Keane, D Kiryluk, J Kisiel, A Klay, J Klein, SR Klyachko, A Konstantinov, AS Kopytine, M Kotchenda, L Kovalenko, AD Kramer, M Kravtsov, P Krueger, K Kuhn, C Kulikov, AI Kunde, GJ Kunz, CL Kutuev, RK Kuznetsov, AA Lakehal-Ayat, L Lamont, MAC Landgraf, JM Lange, S Lansdell, CP Lasiuk, B Laue, F Lebedev, A Lednicky, R Leontiev, VM LeVine, MJ Li, Q Lindenbaum, SJ Lisa, MA Liu, F Liu, L Liu, Z Liu, QJ Ljubicic, T Llope, WJ LoCurto, G Long, H Longacre, RS Lopez-Noriega, M Love, WA Ludlam, T Lynn, D Ma, J Majka, R Margetis, S Markert, C Martin, L Marx, J Matis, HS Matulenko, YA McShane, TS Meissner, F Melnick, Y Meschanin, A Messer, M Miller, ML Milosevich, Z Minaev, NG Mitchell, J Moiseenko, VA Moore, CF Morozov, V de Moura, MM Munhoz, MG Nelson, JM Nevski, P Nikitin, VA Nogach, LV Norman, B Nurushev, SB Nystrand, J Odyniec, G Ogawa, A Okorokov, V Oldenburg, M Olson, D Paic, G Pandey, SU Panebratsev, Y Panitkin, SY Pavlinov, AI Pawlak, T Perevoztchikov, V Peryt, W Petrov, VA Planinic, M Pluta, J Porile, N Porter, J Poskanzer, AM Potrebenikova, E Prindle, D Pruneau, C Putschke, J Rai, G Rakness, G Ravel, O Ray, RL Razin, SV Reichhold, D Reid, JG Retiere, F Ridiger, A Ritter, HG Roberts, JB Rogachevski, OV Romero, JL Roy, C Rykov, V Sakrejda, I Salur, S Sandweiss, J Saulys, AC Savin, I Schambach, J Scharenberg, RP Schmitz, N Schroeder, LS Schuttauf, A Schweda, K Seger, J Seliverstov, D Seyboth, P Shahaliev, E Shestermanov, KE Shimanskii, SS Shvetcov, VS Skoro, G Smirnov, N Snellings, R Sorensen, P Sowinski, J Spinka, HM Srivastava, B Stephenson, EJ Stock, R Stolpovsky, A Strikhanov, M Stringfellow, B Struck, C Suaide, AAP Sugarbaker, E Suire, C Sumbera, M Surrow, B Symons, TJM de Toledo, AS Szarwas, P Tai, A Takahashi, J Tang, AH Thomas, JH Thompson, M Tikhomirov, V Tokarev, M Tonjes, MB Trainor, TA Trentalange, S Tribble, RE Trofimov, V Tsai, O Ullrich, T Underwood, DG Van Buren, G VanderMolen, AM Vasilevski, IM Vasiliev, AN Vigdor, SE Voloshin, SA Wang, F Ward, H Watson, JW Wells, R Westfall, GD Whitten, C Wieman, H Willson, R Wissink, SW Witt, R Wood, J Xu, N Xu, Z Yakutin, AE Yamamoto, E Yang, J Yepes, P Yurevich, VI Zanevski, YV Zborovsky, I Zhang, H Zhang, WM Zoulkarneev, R Zubarev, AN CA STAR Collaboration TI Coherent rho(0) production in ultraperipheral heavy-ion collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID VECTOR-MESON PRODUCTION; PHOTON; PHOTOPRODUCTION; SPECTRA; PHYSICS; HERA AB The STAR Collaboration reports the first observation of exclusive rho(0) photoproduction, AuAu-->AuAurho(0), and rho(0) production accompanied by mutual nuclear Coulomb excitation, AuAu-->Au(star)Au(star)rho(0), in ultraperipheral heavy-ion collisions. The rho(0) have low transverse momenta, consistent with coherent coupling to both nuclei. The cross sections at s(NN)=130 GeV agree with theoretical predictions treating rho(0) production and Coulomb excitation as independent processes. C1 Univ Frankfurt, D-6000 Frankfurt, Germany. Joint Inst Nucl Res Dubna, Particle Phys Lab, Dubna, Russia. Indiana Univ, Bloomington, IN 47408 USA. Inst Rech Subatom, Strasbourg, France. Kent State Univ, Kent, OH 44242 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Max Planck Inst Phys & Astrophys, D-80805 Munich, Germany. Michigan State Univ, E Lansing, MI 48824 USA. Moscow Phys Engn Inst, Moscow, Russia. Cuny City Coll, New York, NY 10031 USA. Ohio State Univ, Columbus, OH 43210 USA. Penn State Univ, University Pk, PA 16802 USA. Inst High Energy Phys, Protvino, Russia. Purdue Univ, W Lafayette, IN 47907 USA. Rice Univ, Houston, TX 77251 USA. Univ Sao Paulo, Sao Paulo, Brazil. SUBATECH, Nantes, France. Texas A&M Univ, College Stn, TX 77843 USA. Univ Texas, Austin, TX 78712 USA. Warsaw Univ Technol, Warsaw, Poland. Univ Washington, Seattle, WA 98195 USA. Wayne State Univ, Detroit, MI 48201 USA. HZNU, CCNU, Inst Particle Phys, Wuhan 430079, Peoples R China. Yale Univ, New Haven, CT 06520 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Birmingham, Birmingham, W Midlands, England. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Creighton Univ, Omaha, NE 68178 USA. Joint Inst Nucl Res Dubna, Lab High Energy, Dubna, Russia. RP Adler, C (reprint author), Univ Frankfurt, D-6000 Frankfurt, Germany. RI Skoro, Goran/F-3642-2010; Sumbera, Michal/O-7497-2014; Barnby, Lee/G-2135-2010; Takahashi, Jun/B-2946-2012; Chen, Yu/E-3788-2012; Planinic, Mirko/E-8085-2012; Witt, Richard/H-3560-2012; Castillo Castellanos, Javier/G-8915-2013; Voloshin, Sergei/I-4122-2013; Johnson, Ian/I-2439-2013; Lednicky, Richard/K-4164-2013; Zborovsky, Imrich/G-7964-2014; Skoro, Goran/P-1229-2014; Strikhanov, Mikhail/P-7393-2014; Kisiel, Adam/O-8754-2015; Tikhomirov, Vladimir/M-6194-2015; Chaloupka, Petr/E-5965-2012; Suaide, Alexandre/L-6239-2016 OI Sumbera, Michal/0000-0002-0639-7323; Barnby, Lee/0000-0001-7357-9904; Takahashi, Jun/0000-0002-4091-1779; Castillo Castellanos, Javier/0000-0002-5187-2779; Skoro, Goran/0000-0001-7745-9045; Strikhanov, Mikhail/0000-0003-2586-0405; Kisiel, Adam/0000-0001-8322-9510; Tikhomirov, Vladimir/0000-0002-9634-0581; Suaide, Alexandre/0000-0003-2847-6556 NR 32 TC 84 Z9 84 U1 0 U2 13 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 30 PY 2002 VL 89 IS 27 AR 272302 DI 10.1103/PhysRevLett.89.272302 PG 6 WC Physics, Multidisciplinary SC Physics GA 627RX UT WOS:000179949600013 PM 12513197 ER PT J AU Coldea, AI Blundell, SJ Steer, CA Mitchell, JF Pratt, FL AF Coldea, AI Blundell, SJ Steer, CA Mitchell, JF Pratt, FL TI Spin freezing and magnetic inhomogeneities in bilayer manganites SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLOSSAL MAGNETORESISTANCE; LAYERED MANGANITES; PHASE-SEPARATION; CHARGE; MUON; LA2-2XSR1+2XMN2O7; ANTIFERROMAGNETISM; LA1-XCAXMNO3; LA2-XSRXCUO4; LASR2MN2O7 AB We have performed a muon spin rotation study on polycrystalline samples of electron-doped layered manganites, La2-2xSr1+2xMn2O7 (0.4less than or equal tox<1), in order to investigate the local magnetic structure and spin dynamics. Our results provide evidence for phase separation into A-type antiferromagnetic and charge-ordered phases for x=0.52 and spin freezing at low temperatures (T<100 K) for 0.52less than or equal tox<0.75. A new phase diagram which includes this spin-freezing region is proposed. C1 Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. RP Coldea, AI (reprint author), Univ Oxford, Clarendon Lab, Parks Rd, Oxford OX1 3PU, England. RI Coldea, Amalia/C-1106-2013 NR 25 TC 16 Z9 16 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 DEC 30 PY 2002 VL 89 IS 27 AR 277601 DI 10.1103/PhysRevLett.89.277601 PG 4 WC Physics, Multidisciplinary SC Physics GA 627RX UT WOS:000179949600056 PM 12513240 ER PT J AU Eschrig, M Norman, MR AF Eschrig, M Norman, MR TI Dispersion anomalies in bilayer cuprates and the odd symmetry of the magnetic resonance SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEUTRON-SCATTERING; OVERDOPED BI2SR2CACU2O8+DELTA; SUPERCONDUCTING STATE; GAP ANISOTROPY; PHOTOEMISSION; EXCITATIONS; YBA2CU3O7; BANDS AB We demonstrate that recent angle resolved photoemission data in bilayer cuprate superconductors imply that scattering of electrons between bonding and antibonding bands is strong compared to scattering within these bands. As a consequence, the resulting data can be reproduced only by a model which assumes that the electrons are interacting with a bosonic mode that is odd with respect to the layer indices. This odd symmetry is a unique property of the magnetic resonance observed by inelastic neutron scattering. C1 Univ Karlsruhe, Inst Theoret Festkorperphys, D-76128 Karlsruhe, Germany. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Eschrig, M (reprint author), Univ Karlsruhe, Inst Theoret Festkorperphys, Kaiserstr 12, D-76128 Karlsruhe, Germany. RI Eschrig, Matthias/B-4786-2009; Norman, Michael/C-3644-2013; OI Eschrig, Matthias/0000-0003-4954-5549 NR 21 TC 46 Z9 46 U1 2 U2 7 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 DEC 30 PY 2002 VL 89 IS 27 AR 277005 DI 10.1103/PhysRevLett.89.277005 PG 4 WC Physics, Multidisciplinary SC Physics GA 627RX UT WOS:000179949600052 PM 12513236 ER PT J AU Hudson, SR Monticello, DA Reiman, AH Boozer, AH Strickler, DJ Hirshman, SP Zarnstorff, MC AF Hudson, SR Monticello, DA Reiman, AH Boozer, AH Strickler, DJ Hirshman, SP Zarnstorff, MC TI Eliminating islands in high-pressure free-boundary stellarator magnetohydrodynamic equilibrium solutions SO PHYSICAL REVIEW LETTERS LA English DT Article ID FIELDS AB Magnetic islands in free-boundary stellarator equilibria are suppressed using a procedure that iterates the plasma equilibrium equations and, at each iteration, adjusts the coil geometry to cancel resonant fields produced by the plasma. The coils are constrained to satisfy certain measures of engineering acceptability and the plasma is constrained to ensure kink stability. As the iterations continue, the coil geometry and the plasma simultaneously converge to an equilibrium in which the island content is negligible. The method is applied with success to a candidate plasma and coil design for the National Compact Stellarator Experiment [Phys. Plasmas10.1063/1.1351826 8, 2083 (2001)]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Columbia Univ, New York, NY 10027 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hudson, SR (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Hudson, Stuart/H-7186-2013 OI Hudson, Stuart/0000-0003-1530-2733 NR 20 TC 18 Z9 18 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 30 PY 2002 VL 89 IS 27 AR 275003 DI 10.1103/PhysRevLett.89.275003 PG 4 WC Physics, Multidisciplinary SC Physics GA 627RX UT WOS:000179949600028 PM 12513212 ER PT J AU Morris, CL Anaya, JM Bowles, TJ Filippone, BW Geltenbort, P Hill, RE Hino, M Hoedl, S Hogan, GE Ito, TM Kawai, T Kirch, K Lamoreaux, SK Liu, CY Makela, M Marek, LJ Martin, JW Mortensen, RN Pichlmaier, A Saunders, A Seestrom, SJ Smith, D Teasdale, W Tipton, B Utsuro, M Young, AR Yuan, J AF Morris, CL Anaya, JM Bowles, TJ Filippone, BW Geltenbort, P Hill, RE Hino, M Hoedl, S Hogan, GE Ito, TM Kawai, T Kirch, K Lamoreaux, SK Liu, CY Makela, M Marek, LJ Martin, JW Mortensen, RN Pichlmaier, A Saunders, A Seestrom, SJ Smith, D Teasdale, W Tipton, B Utsuro, M Young, AR Yuan, J TI Measurements of ultracold-neutron lifetimes in solid deuterium SO PHYSICAL REVIEW LETTERS LA English DT Article ID INELASTICALLY SCATTERED NEUTRONS; ELECTRIC-DIPOLE MOMENT; COLD NEUTRONS; SUPERFLUID-HELIUM; STORAGE; RATES; UCN AB We present the first measurements of the survival time of ultracold neutrons (UCNs) in solid deuterium (SD2). This critical parameter provides a fundamental limitation to the effectiveness of superthermal UCN sources that utilize solid ortho-deuterium as the source material. These measurements are performed utilizing a SD2 source coupled to a spallation source of neutrons, providing a demonstration of UCN production in this geometry and permitting systematic studies of the influence of thermal up-scatter and contamination with para-deuterium on the UCN survival time. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CALTECH, Kellogg Radiat Lab, Pasadena, CA 91125 USA. Inst Max Von Laue Paul Langevin, F-3804 Grenoble, France. Kyoto Univ, Kyoto 6068501, Japan. Princeton Univ, Princeton, NJ 08544 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. N Carolina State Univ, Raleigh, NC 27695 USA. RP Morris, CL (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Yuan, Junhua/C-7923-2009; Kirch, Klaus/A-4601-2010; Anaya, Juan-Manuel/J-1960-2016 OI Anaya, Juan-Manuel/0000-0002-6444-1249 NR 26 TC 36 Z9 36 U1 0 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 30 PY 2002 VL 89 IS 27 AR 272501 DI 10.1103/PhysRevLett.89.272501 PG 4 WC Physics, Multidisciplinary SC Physics GA 627RX UT WOS:000179949600014 PM 12513198 ER PT J AU Murayama, H Pierce, A AF Murayama, H Pierce, A TI Realistic Dirac leptogenesis SO PHYSICAL REVIEW LETTERS LA English DT Article ID CP VIOLATION; BARYOGENESIS; NEUTRINOS AB We present a model of leptogenesis that preserves lepton number. The model maintains the important feature of more traditional leptogenesis scenarios: The decaying particles that provide the CP violation necessary for baryogenesis also provide the explanation for the smallness of the neutrino Yukawa couplings. This model clearly demonstrates that, contrary to conventional wisdom, neutrinos need not be Majorana in nature in order to help explain the baryon asymmetry of the universe. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Murayama, Hitoshi/A-4286-2011 NR 25 TC 50 Z9 50 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 30 PY 2002 VL 89 IS 27 AR 271601 DI 10.1103/PhysRevLett.89.271601 PG 4 WC Physics, Multidisciplinary SC Physics GA 627RX UT WOS:000179949600007 PM 12513191 ER PT J AU Ogasawara, H Brena, B Nordlund, D Nyberg, M Pelmenschikov, A Pettersson, LGM Nilsson, A AF Ogasawara, H Brena, B Nordlund, D Nyberg, M Pelmenschikov, A Pettersson, LGM Nilsson, A TI Structure and bonding of water on Pt(111) SO PHYSICAL REVIEW LETTERS LA English DT Article ID RAY-ABSORPTION SPECTRA; FUNDAMENTAL-ASPECTS; SOLID-SURFACES; CORE-LEVEL; ADSORPTION; ICE; H2O; MOLECULES; RU(001); BILAYER AB We address the adsorption of water on Pt(111) using x-ray absorption, x-ray emission, and x-ray photoelectron spectroscopy along with calculations in the framework of density functional theory. Using the direct relationship between the electronic structure and adsorbate geometry, we show that in the first layer all the molecules bind directly to the surface and to each other through the in-layer H bonds without dissociation, creating a nearly flat overlayer. The water molecules are adsorbed through alternating metal-oxygen (M-O) and metal-hydrogen (M-HO) bonds. C1 Stockholm Univ, Albanova Univ Ctr, FYSIKUM, S-10691 Stockholm, Sweden. Uppsala Univ, Dept Phys, S-75121 Uppsala, Sweden. Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RP Ogasawara, H (reprint author), Stockholm Univ, Albanova Univ Ctr, FYSIKUM, S-10691 Stockholm, Sweden. RI Nilsson, Anders/E-1943-2011; Pettersson, Lars/F-8428-2011; Nordlund, Dennis/A-8902-2008; Pettersson, Lars/J-4925-2013; Brena, Barbara/C-5909-2014; Ogasawara, Hirohito/D-2105-2009 OI Nilsson, Anders/0000-0003-1968-8696; Nordlund, Dennis/0000-0001-9524-6908; Pettersson, Lars/0000-0003-1133-9934; Ogasawara, Hirohito/0000-0001-5338-1079 NR 24 TC 327 Z9 330 U1 5 U2 100 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 DEC 30 PY 2002 VL 89 IS 27 AR 276102 DI 10.1103/PhysRevLett.89.276102 PG 4 WC Physics, Multidisciplinary SC Physics GA 627RX UT WOS:000179949600037 PM 12513221 ER PT J AU Tegze, M Faigel, G Marchesini, S AF Tegze, M Faigel, G Marchesini, S TI Comment on "X-ray absorption holography" SO PHYSICAL REVIEW LETTERS LA English DT Editorial Material C1 Res Inst Solid State Phys & Opt, H-1525 Budapest, Hungary. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Tegze, M (reprint author), Res Inst Solid State Phys & Opt, POB 49, H-1525 Budapest, Hungary. RI Marchesini, Stefano/A-6795-2009 NR 6 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 30 PY 2002 VL 89 IS 27 AR 279601 DI 10.1103/PhysRevLett.89.279601 PG 1 WC Physics, Multidisciplinary SC Physics GA 627RX UT WOS:000179949600068 PM 12513252 ER PT J AU Volkow, ND Wang, GJ Maynard, L Fowler, JS Jayne, B Telang, F Logan, J Ding, YS Gatley, SJ Hitzemann, R Wong, C Pappas, N AF Volkow, ND Wang, GJ Maynard, L Fowler, JS Jayne, B Telang, F Logan, J Ding, YS Gatley, SJ Hitzemann, R Wong, C Pappas, N TI Effects of alcohol detoxification on dopamine D2 receptors in alcoholics: a preliminary study SO PSYCHIATRY RESEARCH-NEUROIMAGING LA English DT Article DE positron emission tomography; raclopride; addiction; predisposition; GABA cells; striatum; reward ID TAQI A1 ALLELE; DEPENDENT SUBJECTS; NUCLEUS-ACCUMBENS; PREFERRING RATS; NO ASSOCIATION; INBRED STRAINS; HUMAN-BRAIN; GENE; BINDING; METABOLISM AB Imaging studies in patients with Type II alcohol dependence have revealed significant reductions in dopamine (DA) D2 receptor availability. Here we assessed the effects of alcohol detoxification in DA D2 receptors in alcoholic subjects. We evaluated 14 patients with Type II alcohol dependence tested within 6 weeks of detoxification and then re-tested 1-4 months later while alcohol free. The comparison group comprised 11 healthy controls. PET was used with [C-11]raclopride to measure DA D2 receptors. Eight alcoholics and all control subjects were tested with a CTI 931 PET scanner and six alcoholics with a Siemens HR+ PET scanner. Data were analyzed separately for the studies done in the different scanners. Comparisons between early and late alcohol detoxification showed no significant changes in DA D2 receptor availability (B-max/K-d) for the studies done with the CTI and the HR+ scanners. Comparison with controls showed lower DA D2 receptor levels in caudate and putamen in alcoholics tested during early detoxification and in caudate during late detoxification. These studies replicate previous findings of lower striatal DA D2 receptors in alcoholics than in controls and absence of significant recovery during alcohol detoxification. These findings suggest that low DA D2 receptor availability in alcoholics is not due to alcohol withdrawal and may reflect a predisposing factor. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Dept Med, Bldg 490, Upton, NY 11973 USA. FU NIAAA NIH HHS [AA09481] NR 62 TC 100 Z9 103 U1 7 U2 11 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0925-4927 J9 PSYCHIAT RES-NEUROIM JI Psychiatry Res. Neuroimaging PD DEC 30 PY 2002 VL 116 IS 3 BP 163 EP 172 AR PII S0925-4927(02)00087-2 DI 10.1016/S0925-4927(02)00087-2 PG 10 WC Clinical Neurology; Neuroimaging; Psychiatry SC Neurosciences & Neurology; Psychiatry GA 637WB UT WOS:000180535800003 PM 12477600 ER PT J AU Mishin, EV Foster, JC Potekhin, AP Rich, FJ Schlegel, K Yumoto, K Taran, VI Ruohoniemi, JM Friedel, R AF Mishin, EV Foster, JC Potekhin, AP Rich, FJ Schlegel, K Yumoto, K Taran, VI Ruohoniemi, JM Friedel, R TI Global ULF disturbances during a stormtime substorm on 25 September 1998 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE ULF stormtime disturbances; solar wind drivers ID INTERPLANETARY MAGNETIC-FIELD; SOLAR-WIND; IONOSPHERIC CONVECTION; LINE RESONANCES; INNER MAGNETOSPHERE; ELECTRIC-FIELDS; ION DRIFTS; POLAR-CAP; DAYSIDE; INJECTIONS AB Quasiperiodic perturbations of ionospheric plasma with similar to10 min occurrence periods were observed by incoherent scatter radars (ISR) in high-latitude and midlatitude ionosphere after the onset of a stormtime substorm. The latter occurred during a period of complex dynamical activity and had a number of unusual characteristics. The perturbations indicate ultralow frequency (ULF) electric field enhancements over the Northern Hemisphere. Specifically, strong subauroral electric fields are associated with the ring current-related polarization jet (PJ). These perturbations correlate with magnetic variations in high-latitude and midlatitude regions spanning similar to21 hours in magnetic local time (MLT). The radar and ground magnetometer data are supported by simultaneous observations from the DMSP and geostationary satellites. As a result of the onset, the preexisting PJ shifted equatorward to Lsimilar to2.5. Similar periodicities in the solar wind dynamic pressure and interplanetary magnetic field (IMF) appear to be natural sources of the ULF perturbations observed at high and middle latitudes. C1 Boston Coll, Inst Sci Res, Chestnut Hill, MA 02467 USA. MIT, Haystack Observ, ASG, Westford, MA 01886 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RAS, Inst Solar Terr Phys, Irkutsk, Russia. USAF, Res Lab, VSBX, Hanscom AFB, MA 01731 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Max Planck Inst Aeron, D-37191 Lindau, Germany. NAS & ME, Inst Ionenphys, Kharkov, Ukraine. Kyushu Univ 33, Fukuoka 8128581, Japan. RP Mishin, EV (reprint author), Boston Coll, Inst Sci Res, 402 St Clements Hall,140 Commonwealth Ave, Chestnut Hill, MA 02467 USA. RI Friedel, Reiner/D-1410-2012 OI Friedel, Reiner/0000-0002-5228-0281 NR 55 TC 19 Z9 19 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 28 PY 2002 VL 107 IS A12 AR 1486 DI 10.1029/2002JA009302 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 650BT UT WOS:000181243000003 ER PT J AU Neugebauer, M Liewer, PC Smith, EJ Skoug, RM Zurbuchen, TH AF Neugebauer, M Liewer, PC Smith, EJ Skoug, RM Zurbuchen, TH TI Sources of the solar wind at solar activity maximum SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE solar wind sources; solar active regions; coronal holes ID ION COMPOSITION SPECTROMETER; STREAM INTERFACES; MAGNETIC-FIELD; HELIOGRAPHIC LATITUDES; PLASMA OBSERVATIONS; ULYSSES PLASMA; REGIONS; MODELS; HOLES; CORONA AB The photospheric sources of solar wind observed by the Ulysses and ACE spacecraft from 1998 to early 2001 are determined through a two-step mapping process. Solar wind speed measured at the spacecraft is used in a ballistic model to determine a foot point on a source surface at a solar distance of 2.5 solar radii. A potential-field source-surface model is then used to trace the field and flow from the source surface to the photosphere. Comparison of the polarity of the measured interplanetary field with the polarity of the photospheric source region shows good agreement for spacecraft latitudes equatorward of 60degrees. At higher southern latitudes, the mapping predicts that Ulysses should have observed only outward directed magnetic fields, whereas both polarities were observed. A detailed analysis is performed on four of the solar rotations for which the mapped and observed polarities were in generally good agreement. For those rotations, the solar wind mapped to both coronal holes and active regions. These findings for a period of high solar activity differ from the findings of a similar study of the solar wind in 1994-1995 when solar activity was very low. At solar minimum the fastest wind mapped to the interior of large polar coronal holes while slower wind mapped to the boundaries of those holes or to smaller low-latitude coronal holes. For the data examined in the present study, neither spacecraft detected wind from the small polar coronal holes when they existed and the speed was never as high as that observed by Ulysses at solar minimum. The principal difference between the solar wind from coronal holes and from active regions is that the O7+/O6+ ion ratio is lower for the coronal hole flow, but not as low as in the polar coronal hole flow at solar minimum. Furthermore, the active-region flows appear to be organized into several substreams unlike the more monolithic structure of flows from coronal holes. The boundaries between plasma flows from neighboring sources are marked by large magnetic holes, plasma sheets, and low entropy, independent of whether the sources have the same or opposite magnetic polarities. The evolution of solar wind properties between 1 AU and the 1.6-5.4 AU solar distance of Ulysses is also briefly discussed. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Michigan, Space Phys Res Lab, Ann Arbor, MI 48109 USA. RP Neugebauer, M (reprint author), Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. NR 41 TC 76 Z9 77 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 28 PY 2002 VL 107 IS A12 AR 1488 DI 10.1029/JA000306 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 650BT UT WOS:000181243000001 ER PT J AU Yin, L Winske, D AF Yin, L Winske, D TI Simulations of current sheet thinning and reconnection SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE magnetic reconnection; current sheet; numerical simulation studies ID COLLISIONLESS MAGNETIC RECONNECTION; SPACE PLASMAS; GROWTH-PHASE; MAGNETOTAIL; HYBRID; SUBSTORM; TAIL; CONFIGURATIONS; DISSIPATION; CONVECTION AB Thin current sheet structures with a thickness comparable to the ion gyro-radius have been inferred from spacecraft observations during substorms. This study presents two-dimensional hybrid and Hall-MHD simulations of current sheet thinning and reconnection that include electron pressure tensor effects. Results demonstrate that reconnection occurs due to the electron pressure tensor effects as the sheet is compressed by the application of an out-of-plane electric field on the lobe boundaries. Results from hybrid and Hall-MHD calculations for the current sheet thinning process are compared. During the thinning period, the out-of-plane ion velocity from the hybrid simulation shows an enhancement at the edge of the sheet and a reduction at the sheet center. As reconnection proceeds, it becomes peaked along the Earth-tail direction away from the X point. In contrast, the out-of-plane ion velocity from the Hall-MHD simulation remains peaked at the center of the simulation. The ion off-diagonal pressure tensor effects are considered as the cause of the differing particle-ion and fluid-ion dynamics. The dynamics of current sheet thinning and reconnection is also modeled using a new integrated approach in which Hall-MHD calculations are embedded inside an MHD simulation. It is shown that the embedded simulation can provide smooth transitions of plasma and field quantities between the two regions, and the small-scale physics in the compressed current sheet and in the near-X-point region are well represented. C1 Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Yin, L (reprint author), Los Alamos Natl Lab, Div Appl Phys, Mail Stop B259, Los Alamos, NM 87545 USA. NR 36 TC 12 Z9 13 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 28 PY 2002 VL 107 IS A12 AR 1485 DI 10.1029/2002JA009507 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 650BT UT WOS:000181243000005 ER PT J AU Assink, RA Celina, M Minier, LM AF Assink, RA Celina, M Minier, LM TI Condition monitoring of a by H-1-NMR T-2 relaxation solvent-swelled samples thermally aged elastomer measurements of SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE ageing; polybutadiene; degradation; NMR; solution properties ID TERMINATED POLYBUTADIENE HTPB; DECOMPOSITION; EXTRAPOLATION; DEGRADATION; ARRHENIUS; DYNAMICS; RUBBER; NMR AB The aging of polymers is often monitored by mechanical property measurements such as those of Young's modulus or tensile elongation at break; new methods are required, however, in situations where traditional mechanical methods cannot be employed. A hydroxy-terminated polybutadiene/isophorone diisocyanate elastomer is commonly used as a propellant binder. The thermal degradation of the binder is believed to be an important parameter governing the performance of the propellant. Classical mechanical methods cannot be used to monitor the condition of this material when it has been aged in situ as a highly dispersed binder. In this study, the H-1-NMR spin-spin relaxation times, T-2, of solvent-swelled samples decreased substantially as thermally induced oxidation led to additional crosslinking. A time-temperature superposition analysis of the relaxation times was performed on samples that had been aged at temperatures ranging from 50 to 125degreesC. The acceleration factors derived from the relaxation measurements agreed with those reported earlier for tensile elongation at break and oxygen consumption. The dependence of T-2 on tensile elongation at break was independent of the temperature at which the sample was aged. A shortened version of the experiment, requiring only two spin-echo delay times, is presented. (C) 2002 Wiley Periodicals, Inc. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Assink, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 14 TC 8 Z9 9 U1 0 U2 6 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD DEC 27 PY 2002 VL 86 IS 14 BP 3636 EP 3641 DI 10.1002/app.11289 PG 6 WC Polymer Science SC Polymer Science GA 612JM UT WOS:000179071100022 ER PT J AU Morrow, JA Hatters, DM Lu, B Hochtl, P Oberg, KA Rupp, B Weisgraber, KH AF Morrow, JA Hatters, DM Lu, B Hochtl, P Oberg, KA Rupp, B Weisgraber, KH TI Apolipoprotein E4 forms a molten globule - A potential basis for its association with disease SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID TRANSFORM INFRARED-SPECTROSCOPY; RECEPTOR-RELATED PROTEIN; AMINO-TERMINAL DOMAIN; ALZHEIMERS-DISEASE; NEURITE OUTGROWTH; MYOCARDIAL-INFARCTION; LIPID-BINDING; E ISOFORMS; CONFORMATIONAL-CHANGES; AQUEOUS-SOLUTION AB The amino-terminal domain of apolipoprotein (apo) E4 is less susceptible to chemical and thermal denaturation than the apoE3 and apoE2 domains. We compared the urea denaturation curves of the 22-kDa amino-terminal domains of the apoE isoforms at pH 7.4 and 4.0. At pH 7.4, apoE3 and apoE4 reflected an apparent two-state denaturation. The midpoints of denaturation were 5.2 and 4.3 M urea, respectively. At pH 4.0, a pH value known to stabilize folding intermediates, apoE4 and apoE3 displayed the same order of denaturation but with distinct plateaus, suggesting the presence of a stable folding intermediate. In contrast, apoE2 proved the most stable and lacked the distinct plateau observed with the other two isoforms and could be fitted to a two-state unfolding model. Analysis of the curves with a three-state unfolding model (native, intermediate, and unfolded) showed that the apoE4 folding intermediate reached its maximal concentration (approximate to90% of the mixture) at 3.75 M, whereas the apoE3 intermediate was maximal at 4.75 M (approximate to80%). These results are consistent with apoE4 being more susceptible to unfolding than apoE3 and apoE2 and more prone to form a stable folding intermediate. The structure of the apoE4 folding intermediate at pH 4.0 in 3.75 m urea was characterized using pepsin proteolysis, Fourier transform infrared spectroscopy, and dynamic light scattering. From these studies, we conclude that the apoE4 folding intermediate is a single molecule with the characteristics of a molten globule. We propose a model of the apoE4 molten globule in which the four-helix bundle of the amino-terminal domain is partially opened, generating a slightly elongated structure and exposing the hydrophobic core. Since molten globules have been implicated in both normal and abnormal physiological function, the differential abilities of the apoE isoforms to form a molten globule may contribute to the isoform-specific effects of apoE in disease. C1 Gladstone Inst Cardiovasc Dis, San Francisco, CA 94141 USA. Gladstone Inst Neurol Dis, San Francisco, CA 94141 USA. Univ Calif San Francisco, Dept Pathol, San Francisco, CA 94143 USA. Univ Calif San Francisco, Inst Cardiovasc Res, San Francisco, CA 94143 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Allecure Inc, Los Angeles, CA 91355 USA. RP Weisgraber, KH (reprint author), Gladstone Inst Cardiovasc Dis, POB 419100, San Francisco, CA 94141 USA. OI Hatters, Danny/0000-0002-9965-2847 FU NINDS NIH HHS [NS35939] NR 55 TC 127 Z9 131 U1 2 U2 8 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 DEC 27 PY 2002 VL 277 IS 52 BP 50380 EP 50385 DI 10.1074/jbc.M204898200 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 631QD UT WOS:000180177700023 PM 12393895 ER PT J AU Thrall, KD Gies, RA Muniz, J Woodstock, AD Higgins, G AF Thrall, KD Gies, RA Muniz, J Woodstock, AD Higgins, G TI Route-of-entry and brain tissue partition coefficients for common Superfund contaminants SO JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A LA English DT Article ID PHYSIOLOGICAL PHARMACOKINETIC MODELS; VOLATILE ORGANIC-CHEMICALS; RAT-BLOOD; COMPONENTS; PREDICTION; EXPOSURES; MIXTURES; WATER AB Various organic solvents may be encountered in contaminated water supplies at U.S. Environmental Protection Agency-designated Superfund sites. Human exposure to these environmental contaminants may occur by oral, dermal, or inhalation routes. The estimation of human health risk associated with exposure to these solvents can be improved through the use of physiologically based pharmacokinetic (PBPK) models to describe the absorption, tissue distribution, metabolism, and elimination of the compounds following any route of exposure. However, development of these PBPK models requires information on the relative solubility, or partition coefficient, of each compound in blood and various tissues. A number of investigators have provided partition coefficient information on different tissues in various species; however, the data for route of entry organs (i.e., skin, lung, stomach) and brain tissue are not complete. Therefore, the objective of this work was to replicate partition coefficient studies for several commonly encountered environmental contaminants using an in vitro gas-phase vial equilibration technique and to include tissues to evaluate brain, lung, stomach, and skin. A comparison of the partition coefficient values determined here with values reported in the literature, where available, showed good agreement in nearly all cases. An additional study was conducted to compare the liver-to-air partition coefficient values for toluene, benzene, and o-xylene introduced as single chemicals to partition coefficient values determined with the chemicals introduced as a mixture of all three compounds. The similarities of the resulting values suggest that both labor and laboratory resources may be reduced when partition coefficients are determined as chemical mixtures. C1 Pacific NW Natl Lab, Mol Biosci Dept, Fundamental Sci Div, Richland, WA 99352 USA. Oregon Hlth & Sci Univ, Ctr Res Occupat & Environm Toxicol, Portland, OR USA. RP Thrall, KD (reprint author), Pacific NW Natl Lab, Mol Biosci Dept, Fundamental Sci Div, 902 Battelle Blvd,Mail Stop P7-59, Richland, WA 99352 USA. FU NIEHS NIH HHS [1-P42-ES10338-01] NR 23 TC 20 Z9 20 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1528-7394 J9 J TOXICOL ENV HEAL A JI J. TOXICOL. ENV. HEALTH PT A PD DEC 27 PY 2002 VL 65 IS 24 BP 2075 EP 2086 DI 10.1080/00984100290071838 PG 12 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 623NY UT WOS:000179710800002 PM 12515587 ER PT J AU Thrall, KD Woodstock, AD AF Thrall, KD Woodstock, AD TI Evaluation of the dermal absorption of aqueous toluene in F344 rats using real-time breath analysis and physiologically based pharmacokinetic modeling SO JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A LA English DT Article ID CHLOROFORM; EXPOSURE; WATER AB Toluene is a ubiquitous chemical that is commonly used for its solvent properties in industry and manufacturing, and is a component of many paint products. Because of its widespread use, there is potential for both occupational and nonoccupational dermal exposure to toluene. To understand the significance of these exposures, the dermal bioavailability of toluene was assessed in F344 male rats using a combination of real-time exhaled breath analysis and physiologically based pharmacokinetic (PBPK) modeling. Animals were exposed to toluene at 0.5 or 0.2 mg/ml aqueous concentration (0.05% or 0.02%) using a 2.5-cm-diameter occluded glass patch system attached to a clipper-shaved area on the back of the rat. Immediately following exposure, individual animals were placed in a glass off-gassing chamber and exhaled breath was monitored as chamber concentration in real time using an ion-trap mass spectrometer (MS/MS). The real-time exhaled breath profile clearly demonstrated the rapid absorption of toluene, with peak chamber concentrations observed within 1 h from the start of exposure. The PBPK model describing the exposure and off-gassing chamber was used to estimate a dermal permeability coefficient (K-p) to describe each set of exhaled breath data. Regardless of exposure level, a single K-p value of 0.074 +/- 0.005 cm/h provided a good fit to all data sets. These rat studies using aqueous toluene will form the basis for comparing the dermal bioavailability of toluene in various paint products and may ultimately aid in understanding human health risk under a variety of exposure scenarios. C1 Pacific NW Natl Lab, Mol Biosci Dept, Fundamental Sci Div, Richland, WA 99352 USA. RP Thrall, KD (reprint author), Pacific NW Natl Lab, Mol Biosci Dept, Fundamental Sci Div, 902 Battelle Blvd,Mail Stop P7-59, Richland, WA 99352 USA. FU NIOSH CDC HHS [1-R01-OH03658-01A2] NR 17 TC 8 Z9 8 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1528-7394 J9 J TOXICOL ENV HEAL A JI J. TOXICOL. ENV. HEALTH PT A PD DEC 27 PY 2002 VL 65 IS 24 BP 2087 EP 2100 DI 10.1080/00984100290071540 PG 14 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 623NY UT WOS:000179710800003 PM 12515588 ER PT J AU Christian, AT AF Christian, AT TI A cytogenetic footprint for mammary carcinomas induced by PhIP in rats SO TOXICOLOGY LA English DT Article; Proceedings Paper CT 9th International Congress of Toxicology (ICT IX) CY JUL 08-12, 2001 CL QUEENSLAND, AUSTRALIA DE cytogenetic footprinting; mammary carcinomas; PhIP ID ROLLING-CIRCLE AMPLIFICATION; MEDIATED CDNA CAPTURE; PADLOCK PROBES; HYBRIDIZATION; CHROMOSOMES AB 2-Amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP), a mutagen/carcinogen belonging to the class of heterocyclic amines (HCAs) found in cooked meats, is a mammary gland carcinogen in rats and has been implicated in the etiology of certain human cancers including breast cancer. To gain insight into the genomic alterations associated with PhIP-induced mammary gland carcinogenesis, we used comparative genomic hybridization (CGH) to examine chromosomal abnormalities in rat mammary carcinomas induced by PhIP, and for comparison, by DMBA (7, 12-dimethylbenz[a]anthracene), a potent experimental mammary carcinogen. There was a consistent and characteristic pattern of chromosome-region loss in PhIP-induced carcinomas that clearly distinguished them from carcinomas induced by DMBA. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Christian, AT (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808,L-452, Livermore, CA 94551 USA. NR 17 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0300-483X J9 TOXICOLOGY JI Toxicology PD DEC 27 PY 2002 VL 181 BP 95 EP 97 AR PII S0300-483X(02)00261-5 DI 10.1016/S0300-483X(02)00261-5 PG 3 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA 639TX UT WOS:000180646400016 PM 12505291 ER PT J AU Baker, DN Peterson, WK Eriksson, S Li, X Blake, JB Burch, JL Daly, PW Dunlop, MW Korth, A Donovan, E Friedel, R Fritz, TA Frey, HU Mende, SB Roeder, J Singer, HJ AF Baker, DN Peterson, WK Eriksson, S Li, X Blake, JB Burch, JL Daly, PW Dunlop, MW Korth, A Donovan, E Friedel, R Fritz, TA Frey, HU Mende, SB Roeder, J Singer, HJ TI Timing of magnetic reconnection initiation during a global magnetospheric substorm onset SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CLUSTER; MISSION; SHEET; FIELD AB [1] We have used a unique constellation of Earth-orbiting spacecraft and ground-based measurements in order to study a relatively isolated magnetospheric substorm event on August 27, 2001. Global ultraviolet images of the northern auroral region established the substorm expansion phase onset at 0408: 19 (+/-1 min) UT. Concurrent measurements from the GOES-8, POLAR, LANL, and CLUSTER spacecraft allow us to construct a timeline which is consistent with magnetic reconnection on the closed field lines of the central plasma sheet near X-GSM similar to -18 R-E some 7 minutes prior to the near-earth and auroral region times of substorm expansion phase onset. This suggests that magnetic reconnection (i.e., the substorm neutral line) in this case formed in the mid-tail region substantially before current disruption, field dipolarization near geostationary orbit, or auroral substorm onsets occurred. Thus, the magnetic reconnection process is interpreted as the causative driver of dissipation in this well-observed case. C1 Univ Colorado, LASP, Boulder, CO 80309 USA. Aerosp Corp, El Segundo, CA 90245 USA. SW Res Inst, San Antonio, TX 78284 USA. Max Planck Inst, Katlenberg, Lindau, Germany. Univ London Imperial Coll Sci Technol & Med, London SW7 2AZ, England. Univ Calgary, Calgary, AB T2N 1N4, Canada. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. Univ Calif Berkeley, Space Phys Lab, Berkeley, CA 94720 USA. NOAA, Space Environm Ctr, Boulder, CO 80307 USA. RP Baker, DN (reprint author), Univ Colorado, LASP, 1234 Innovat Dr, Boulder, CO 80309 USA. RI Friedel, Reiner/D-1410-2012; Peterson, WK/A-8706-2009 OI Friedel, Reiner/0000-0002-5228-0281; Peterson, WK/0000-0002-1513-6096 NR 11 TC 71 Z9 72 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 26 PY 2002 VL 29 IS 24 AR 2190 DI 10.1029/2002GL015539 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 649WG UT WOS:000181230500001 ER PT J AU Wood, TR Nicholl, MJ Glass, RJ AF Wood, TR Nicholl, MJ Glass, RJ TI Fracture intersections as integrators for unsaturated flow SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB [1] A simple experiment finds that fracture intersections can act to integrate unsaturated flows, such that regular, low flows entering the intersection from above are transformed into large, less frequent pulses below. At low flows, our simple intersection forms two capillary barriers. Water from above pools at the intersection until sufficient pressure builds to breach the barriers and discharge stored fluid. The barriers then reform and the process is repeated. At low flows, the volume discharged from the intersection remains relatively uniform across a range of flow rates. At higher flows, discharge volume is highly variable, and a viscous stabilized non-pulsating regime occurs at the highest flow rate that we considered. C1 INEEL, Idaho Falls, ID 83415 USA. Univ Idaho, Dept Mat Met Min & Geol Engn, Moscow, ID 83844 USA. Sandia Natl Labs, Flow Visualizat & Proc Lab, Albuquerque, NM 87185 USA. RP INEEL, POB 1625,MS 2107, Idaho Falls, ID 83415 USA. EM rjglass@sandia.gov; mnicholl@uidaho.edu; tqw@inel.gov NR 3 TC 16 Z9 16 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 26 PY 2002 VL 29 IS 24 AR 2191 DI 10.1029/2002GL015551 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 649WG UT WOS:000181230500002 ER PT J AU Heavner, MJ Smith, DA Jacobson, AR Sheldon, RJ AF Heavner, MJ Smith, DA Jacobson, AR Sheldon, RJ TI LF/VLF and VHF lightning fast-stepped leader observations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE lightning; leader processes; VHF lightning; VLF lightning; leader velocity ID FORTE OBSERVATIONS; OPTICAL-EMISSIONS; STROKES AB [1] This paper reports multiplatform observations of leader radiation preceding initial cloud-to-ground lightning return strokes by <6 ms. Specifically, we present multistation ground-based LF/VLF recordings of events with large-amplitude leader activity (comparable in amplitude to the return stroke amplitude). The events were selected for their coincidence with VHF observations by the FORTE satellite. Some FORTE VHF leader step observations have obvious direct and ground reflection components. For these steps, which temporally correspond to specific features in the ground LF/VLF field change records, we calculate a source height based on event satellite geometry. We determine source heights between 4.0 and 5.5 km. For FORTE records with multiple reflected events we calculate vertical leader propagation velocities on the order of 10 6 m/s. The determined vertical leader propagation speeds are an order of magnitude greater than those reported as typical values for stepped leader velocities associated with initial return strokes. C1 Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. RP Heavner, MJ (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci Grp, NIS-1,MS D466, Los Alamos, NM 87545 USA. EM heavner@lanl.gov; smithda@lanl.gov; ajacobson@lanl.gov; ricki@lanl.gov NR 17 TC 11 Z9 11 U1 6 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 26 PY 2002 VL 107 IS D24 AR 4791 DI 10.1029/2001JD001290 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 650JA UT WOS:000181258800004 ER PT J AU Cline, J Takahashi, K Marin, TW Jonah, CD Bartels, DM AF Cline, J Takahashi, K Marin, TW Jonah, CD Bartels, DM TI Pulse radiolysis of supercritical water. 1. Reactions between hydrophobic and anionic species SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID SOLVENT DENSITY INHOMOGENEITIES; DIFFUSION-CONTROLLED REACTIONS; COMPRESSIBLE DIELECTRIC FLUID; APPARENT MOLAR VOLUMES; LONG-RANGE STRUCTURE; CHARGED HARD-SPHERE; HYDRATED ELECTRON; LIQUID WATER; TEMPERATURE-DEPENDENCE; INFINITE DILUTION AB Reaction rates of solvated electrons with oxygen and with sulfur hexafluoride were measured in hydrothermal and supercritical water using transient absorption spectroscopy and electron pulse radiolysis. Under alkaline conditions, the reaction of hydrogen atoms with hydroxide ions to generate solvated electrons was also observed in the presence of the SF6 scavenger. At temperatures below 300 degreesC, the rate constants for scavenging by O-2 or SF6 follow Arrhenius behavior but become increasingly dependent on water density (pressure) at higher temperatures. Above 100 degreesC, the rate constant for the H reaction with OH- falls well below the numbers extrapolated from the Arrhenius behavior in the one atmosphere liquid. At a fixed temperature above the water critical temperature (380 degreesC, T/T-c = 1.01), rate constants for all three reactions reach a distinct minimum near 0.45 g/cm(3). We propose an explanation for this behavior in terms of the potential of mean force separating an ion (OH- or (e-)(aq)) from a hydrophobic species (H, O-2, or SF6) in the compressible fluid. The data also reveal an increasing initial yield of atomic hydrogen relative to solvated electrons as water density decreases. The initial yield of H appears to surpass that of solvated electrons when the water density is below 0.6 g/cm(3) at 380 degreesC. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Hokkaido Univ, Div Quantum Energy Engn, Sapporo, Hokkaido 0608628, Japan. RP Bartels, DM (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Marin, Timothy/E-3446-2010; Takahashi, Kenji/C-8846-2011; Takahashi, Kenji/F-4885-2014 NR 66 TC 40 Z9 40 U1 2 U2 14 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 DEC 26 PY 2002 VL 106 IS 51 BP 12260 EP 12269 DI 10.1021/jp0270250 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 628GN UT WOS:000179984900011 ER PT J AU Marin, TW Cline, JA Takahashi, K Bartels, DM Jonah, CD AF Marin, TW Cline, JA Takahashi, K Bartels, DM Jonah, CD TI Pulse radiolysis of supercritical water. 2. Reaction of nitrobenzene with hydrated electrons and hydroxyl radicals SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID SOLVENT STRUCTURE; TEMPERATURE-DEPENDENCE; AQUEOUS-SOLUTION; MIXED-SOLVENTS; SOLVATED ELECTRON; RATE CONSTANTS; ENERGY; DIFFUSION; MOLECULES; HYDROGEN AB The rate constants for the reactions of nitrobenzene with the hydroxyl radical (OH.) and hydrated electron in water have been measured from room temperature to 400 degreesC using electron pulse radiolysis and transient absorption spectroscopy. The diffusion-limited reaction of nitrobenzene with (e(-))(aq) exhibits temperature-insensitive activation energy up to 300 degreesC, indicating that the activation energy for electron diffusion remains high over this range. The (e(-))(aq) reactivity is explained as a long-range electron transfer, and the results are interpreted in terms of extended Marcus theory and Smoluchowski relationships. At 380 degreesC, the rate constant has a density dependence similar to that previously reported for other (e(-))(aq) scavenging reactions. The reaction rate of nitrobenzene with OH. is very insensitive to temperature from room temperature up to 300 degreesC, in agreement with previous studies. Above 300 degreesC, the rate constant increases as the critical temperature is approached and exceeded. Time-resolved electronic absorption spectra of the nitrobenzene radiolysis transients reveal complex kinetics involving multiple absorbing species. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Bartels, DM (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Marin, Timothy/E-3446-2010; Takahashi, Kenji/C-8846-2011; Takahashi, Kenji/F-4885-2014 NR 60 TC 28 Z9 28 U1 1 U2 10 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 DEC 26 PY 2002 VL 106 IS 51 BP 12270 EP 12279 DI 10.1021/jp026812u PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 628GN UT WOS:000179984900012 ER PT J AU Mays, DC Faybishenko, BA Finsterle, S AF Mays, DC Faybishenko, BA Finsterle, S TI Information entropy to measure temporal and spatial complexity of unsaturated flow in heterogeneous media SO WATER RESOURCES RESEARCH LA English DT Article DE unsaturated flow; information entropy; complexity ID IMMISCIBLE FLUIDS; 2-PHASE FLOW; VADOSE ZONE; UNCERTAINTY; FRACTURES; BEHAVIOR; PHYSICS; MODELS; CHALK AB [1] Geologic heterogeneity, coupled with the nonlinear interplay of gravity, capillarity, and applied pressure gradients, results in a rich variety of flow behaviors in unsaturated fractured rocks and porous media. In this paper, we evaluate the complexity of these behaviors using information entropy. We create an empirical probability distribution function directly from a data set, then apply Shannon's definition of information entropy to quantify the complexity of the data. As an example, we use information entropy to evaluate the temporal and spatial complexity of simulated flow processes invoked by infiltration into heterogeneous porous media. Our analysis shows that the complexity of this unsaturated flow process depends on both geologic heterogeneity and uncertainty arising from the flow dynamics. Finally, we investigate the marginal value of additional data collection using randomly selected "virtual wells.'' These calculations demonstrate that computed information entropy increases with additional virtual wells, but the rate of increase declines. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. RP Mays, DC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Bldg 90,Room 1116,1 Cyclotron Rd, Berkeley, CA 94720 USA. EM dcmays@lbl.gov; bafaybishenko@lbl.gov; safinsterle@lbl.gov RI Finsterle, Stefan/A-8360-2009; Mays, David/D-9366-2016; Faybishenko, Boris/G-3363-2015 OI Finsterle, Stefan/0000-0002-4446-9906; Mays, David/0000-0002-5218-1670; Faybishenko, Boris/0000-0003-0085-8499 NR 27 TC 18 Z9 21 U1 2 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 26 PY 2002 VL 38 IS 12 AR 1313 DI 10.1029/2001WR001185 PG 11 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 650EC UT WOS:000181248800001 ER PT J AU Giometti, CS Reich, C Tollaksen, S Babnigg, G Lim, HJ Zhu, WH Yates, J Olsen, G AF Giometti, CS Reich, C Tollaksen, S Babnigg, G Lim, HJ Zhu, WH Yates, J Olsen, G TI Global analysis of a "simple" proteome: Methanococcus jannaschii SO JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES LA English DT Article DE proteomics; Methanococcus jannaschii; two-dimensional gel electrophoresis ID RESOLUTION 2-DIMENSIONAL ELECTROPHORESIS; GEL-ELECTROPHORESIS; TISSUE PROTEINS; CELL FRACTIONS; QUANTITATION; SERUM AB The completed genome of Methanococcus jannaschii, including the main chromosome and two extra-chromosomal elements, predicts a proteome comprised of 1783 proteins. How many of those proteins are expressed at any given time and the relative abundance of the expressed proteins, however, cannot be predicted solely from the genome sequence. Two-dimensional gel electrophoresis coupled with peptide mass spectrometry is being used to identify the proteins expressed by M. jannaschii cells grown under different conditions as part of an effort to correlate protein expression with regulatory mechanisms. Here we describe the identification of 170 of the most abundant proteins found in total lysates of M. jannaschii grown under optimal fermentation conditions. To optimize the number of proteins detected, two different protein specific stains (Coomassie Blue R250 or silver nitrate) and two different first dimension separation methods (isoelectric focusing or nonequilibrium pH gradient electrophoresis) were used. Thirty-two percent of the proteins identified are annotated as hypothetical (21% conserved hypothetical and 11% hypothetical), 21% are enzymes involved in energy metabolism, 12% are proteins required for protein synthesis, and the remainder include proteins necessary for intermediary metabolism, cell division, and cell structure. Evidence of post-translational modification of numerous M. jannaschii proteins has been found, as well as indications of incomplete dissociation of protein-protein complexes. These results demonstrate the complexity of proteome analysis even when dealing with a relatively simple genome. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. Univ Illinois, Dept Biochem, Urbana, IL 61801 USA. Scripps Inst, Mass Spectrometry Grp, La Jolla, CA USA. RP Giometti, CS (reprint author), Argonne Natl Lab, Biosci Div, 9700 S Cass Ave,Bldg B117, Argonne, IL 60439 USA. NR 15 TC 32 Z9 33 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1570-0232 J9 J CHROMATOGR B JI J. Chromatogr. B PD DEC 25 PY 2002 VL 782 IS 1-2 BP 227 EP 243 AR PII S1570-0232(02)00568-8 DI 10.1016/S1570-0232(02)00568-8 PG 17 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 624WR UT WOS:000179785100018 PM 12458009 ER PT J AU He, Y Zhong, WW Yeung, ES AF He, Y Zhong, WW Yeung, ES TI Multiplexed on-column protein digestion and capillary electrophoresis for high-throughput comprehensive peptide mapping SO JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES LA English DT Article DE protein digestion; peptide mapping ID PERFORMANCE LIQUID-CHROMATOGRAPHY; IONIZATION MASS-SPECTROMETRY; ZONE ELECTROPHORESIS; RECOMBINANT PROTEINS; IDENTIFICATION; DESORPTION; MALDI; LEVEL; MIXTURES; TRYPSIN AB A novel scheme based on multiplexed capillary electrophoresis (CE) has been developed for high-throughput, low-cost and comprehensive peptide mapping. Orthogonal peptide maps of the protein of interest were obtained by using multiple reaction conditions with three different enzymes (trypsin, pepsin, and chymotrypsin), and multiple separation conditions with six zone electrophoresis buffers and two micellar electrokinetic chromatography (MEKC) buffers. Fifteen nanoliters of two protein samples (beta-lactoglobulin A and beta-lactoglobulin B) were separately mixed on-column and digested independently at 37 degreesC for 10 min to produce peptides in a 20-capillary system. The resulting peptides were detected simultaneously at 214 nm by a photodiode array detector. The overall analysis time from reaction to detection was about 40 min. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), Iowa State Univ, US DOE, Ames Lab, 332 Wilhelm Hall, Ames, IA 50011 USA. NR 44 TC 16 Z9 16 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1570-0232 J9 J CHROMATOGR B JI J. Chromatogr. B PD DEC 25 PY 2002 VL 782 IS 1-2 BP 331 EP 341 AR PII S1570-0232(02)00698-0 DI 10.1016/S1570-0232(02)00698-0 PG 11 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 624WR UT WOS:000179785100025 PM 12458016 ER PT J AU Fu, RW Yoshizawa, N Dresselhaus, MS Dresselhaus, G Satcher, JH Baumann, TF AF Fu, RW Yoshizawa, N Dresselhaus, MS Dresselhaus, G Satcher, JH Baumann, TF TI XPS study of copper-doped carbon aerogels SO LANGMUIR LA English DT Article ID SURFACE-CHEMISTRY; ACTIVATED CARBONS AB Copper-doped carbon aerogels were investigated by X-ray photoelectron spectroscopy to determine the chemical nature and distribution of the copper species in the aerogel framework. The Cu2p spectra of both the organic and carbon aerogels show a fairly uniform distribution of copper species in the aerogel network, with a slight increase in copper content going from the edge to the center of the monolith. The O1s spectra of the copper-doped organic aerogel indicate that both the carboxyl and hydroxyl groups of the aerogel framework are involved in chelation of the copper ions. After carbonization, the content of the copper detected by XPS decreases significantly as the copper ions are reduced into metallic copper nanoparticles. These nanoparticles are difficult to detect by XPS because they are coated by a thin carbon layer and migrate into the carbon matrix. The carbon skeleton of the copper-doped carbon aerogels is mainly composed of a uniform micro-graphite-like crystalline network, and no copper-carbon bonds were detectable in the aerogel. C1 MIT, Cambridge, MA 02139 USA. Zhongshan Univ, PCFM Lab, Guangzhou 510275, Peoples R China. Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki 3058569, Japan. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Dresselhaus, MS (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. NR 25 TC 46 Z9 51 U1 8 U2 49 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 24 PY 2002 VL 18 IS 26 BP 10100 EP 10104 DI 10.1021/la020556v PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 628CE UT WOS:000179973800010 ER PT J AU Yoon, SJ Helmke, PA Amonette, JE Bleam, WF AF Yoon, SJ Helmke, PA Amonette, JE Bleam, WF TI X-ray absorption and magnetic studies of trivalent lanthanide ions sorbed on pristine and phosphate-modified boehmite surfaces SO LANGMUIR LA English DT Article ID BOND-VALENCE PARAMETERS; LEAD IMMOBILIZATION; AQUEOUS-SOLUTION; INTERFACE; SORPTION; ELEMENTS; APATITE; PRECIPITATION; SPECTROSCOPY; RESONANCE AB The feasibility of immobilizing radionuclides on mineral surfaces was examined in the absence and the presence of phosphate anions, using trivalent lanthanide ions (Eu3+, Gd3+, and Dy3+) as chemical analogues of trivalent actinide radionuclides. The amount of lanthanide ions (Ln(3+)) sorbed on boehmite (gamma-AlOOH) surfaces dramatically increased in the presence of phosphate below pH 5. The structure of the sorbed lanthanide was determined by X-ray absorption spectroscopy, magnetic susceptibility measurements, and electron paramagnetic resonance spectroscopy. We proved Dy3+ forms precipitates on boehmite surfaces in the presence of phosphate, and Gd3+ both in the presence and the absence of phosphate. In the presence of phosphate, however, these rare-earth cations react to form ultrafine particles of LnPO(4) surface precipitates on boehmite surfaces. C1 Univ Wisconsin, Dept Soil Sci, Madison, WI 53706 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Yoon, SJ (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Bldg 901A, Upton, NY 11973 USA. NR 53 TC 7 Z9 7 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 24 PY 2002 VL 18 IS 26 BP 10128 EP 10136 DI 10.1021/la0202226 PG 9 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 628CE UT WOS:000179973800015 ER PT J AU Liu, P Bandara, J Lin, Y Elgin, D Allard, LF Sun, YP AF Liu, P Bandara, J Lin, Y Elgin, D Allard, LF Sun, YP TI Formation of nanocrystalline titanium dioxide in perfluorinated ionomer membrane SO LANGMUIR LA English DT Article ID INTEGRATED CHEMICAL-SYSTEMS; SEMICONDUCTOR PARTICLES; META-PHENOXYTOLUENE; NAFION MEMBRANES; TIO2; CDS; PHOTOCATALYSIS; NANOPARTICLES; STATE; FILMS AB The formation of crystalline titanium dioxide (TiO2) nanoparticles in Nafion membrane structure was investigated. The X-ray powder diffraction and high-resolution transmission electron microscopy (TEM) results show that these nanoparticles are pure anatase TiO2. The TEM results also show that the crystalline TiO2 nanoparticles are ellipse in shape, with an estimated average aspect ratio (long axis/short axis) of 1.4. The average size of the TiO2 nanoparticles, which is independent of the loading of titanium, is similar to the estimated dimensions of the hydrophilic cavities in Nafion membrane in terms of the ion cluster model. However, there is no evidence for any TiO2 nanoparticles in the proposed channels that connect the hydrophilic cavities. The fact that the TiO2 nanoparticles are distributed homogeneously throughout the Nafion membrane structure suggests that the nanoparticles-embedded membrane still maintains a certain degree of porosity. The properties and potential applications of the Nafion-supported crystalline TiO2 nanoparticles are discussed. C1 Clemson Univ, Howard L Hunter Chem Lab, Dept Chem, Clemson, SC 29634 USA. Clemson Univ, Howard L Hunter Chem Lab, Ctr Adv Engn Fibers & Films, Clemson, SC 29634 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Sun, YP (reprint author), Clemson Univ, Howard L Hunter Chem Lab, Dept Chem, Clemson, SC 29634 USA. NR 40 TC 61 Z9 64 U1 0 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 24 PY 2002 VL 18 IS 26 BP 10398 EP 10401 DI 10.1021/la0204621 PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 628CE UT WOS:000179973800050 ER PT J AU Liu, LZ Wan, Q Liu, TB Hsiao, BS Chu, B AF Liu, LZ Wan, Q Liu, TB Hsiao, BS Chu, B TI Salt-induced polymer gelation and formation of nanocrystals in a polymer-salt system SO LANGMUIR LA English DT Article ID MICROPHASE SEPARATION; INORGANIC SALTS; INDUCED CRYSTALLIZATION; COPOLYMER; BEHAVIOR; MIXTURES; COMPLEX AB Salt-induced polymer gelation and nanocrystal fabrication in a polymer-salt system of Pluronic surfactant L35 (E11P16E11) and saturated CdCl2 aqueous solution were studied by means of small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAYD), and transmission electron microscopy (TEM). The symbols Ell and P-16 denote the ethylene oxide end block with 11 segments and the propylene oxide middle block with 16 segments, respectively. The L35 surfactant started to form a gel-like polymer network with only 2 wt % of the saturated CdCl2 solution (weight ratio of CdCl2:H2O = 50:50) in the system. When the amount of salt solution was further increased to 5 wt %, nanocrystals composed mainly of CdCl2 were formed in the gel matrix. In this system, the minimized water content was not the driving force for polymer gelation and microphase separation. The poly(ethylene oxide) (PEO) block in the EPE surfactant could not crystallize by itself, but it could be strongly bonded with salt. The formation of uniform nanocrystals with 3-dimensional ordered packing could be achieved in the presence of soft polymer networks. On the basis of the TEM results, the nanocrystals were found to undergo morphological changes from cubic to rodlike structures, depending on the amount of saturated salt solution. C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11793 USA. RP Chu, B (reprint author), SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RI Liu, Tianbo/D-8915-2017 OI Liu, Tianbo/0000-0002-8181-1790 NR 13 TC 10 Z9 10 U1 3 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 24 PY 2002 VL 18 IS 26 BP 10402 EP 10406 DI 10.1021/la0204803 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 628CE UT WOS:000179973800051 ER PT J AU Rydberg, B Game, J AF Rydberg, B Game, J TI Excision of misincorporated ribonucleotides in DNA by RNase H (type 2) and FEN-1 in cell-free extracts SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID SACCHAROMYCES-CEREVISIAE; ESCHERICHIA-COLI; SUBSTRATE-SPECIFICITY; REVERSE-TRANSCRIPTASE; POLYMERASE-BETA; REPAIR; REPLICATION; SUGAR; DEOXYRIBONUCLEOTIDES; RECOMBINATION AB Misincorporated ribonucleotides in DNA will cause DNA backbone distortion and may be targeted by DNA repair enzymes. Using double-stranded oligonuclecitide probes containing a single ribose, we demonstrate a robust activity in human, yeast, and Escherichia coli cell-free extracts that nicks 5' of the ribose. The human and yeast extracts also make a subsequent cut 3' of the ribonucleotide releasing a ribonucleotide monophosphate. The resulting 1-nt gap is an ideal substrate for polymerase and ligase to complete a proposed repair sequence that effectively replaces the ribose with deoxyribose. Screening of yeast deletion mutant cells reveals that the initial nick is made by RNase H(35), a RNase H type 2 enzyme, and the second cut is made by Rad27p, the yeast homologue of human FEN-1 protein. RNase H type 2 enzymes are present in all kingdoms of life and are evolutionarily well conserved. We knocked out the corresponding rnhb gene in E. coli and show that extracts from this strain lack the nicking activity. Conversely, a highly purified archaeal RNase HLL type 2 protein has a pronounced activity. To study substrate specificity, extracts were made from a yeast double mutant lacking the other main RNase H enzymes [RNase H1 and RNase H(70)], while maintaining RNase H(35). It was found that a single ribose is preferred as substrate over a stretch of riboses, further strengthening a proposed role of this enzyme in the repair of misincorporated ribonucleotides rather than (or in addition to) processing RNA/DNA hybrid molecules. C1 Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Rydberg, B (reprint author), Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NCI NIH HHS [CA80207]; NIGMS NIH HHS [GM599701] NR 30 TC 115 Z9 118 U1 2 U2 8 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 DEC 24 PY 2002 VL 99 IS 26 BP 16654 EP 16659 DI 10.1073/pnas.262591699 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 630HN UT WOS:000180101600029 PM 12475934 ER PT J AU Strausberg, RL Feingold, EA Grouse, LH Derge, JG Klausner, RD Collins, FS Wagner, L Shenmen, CM Schuler, GD Altschul, SF Zeeberg, B Buetow, KH Schaefer, CF Bhat, NK Hopkins, RF Jordan, H Moore, T Max, SI Wang, J Hsieh, F Diatchenko, L Marusina, K Farmer, AA Rubin, GM Hong, L Stapleton, M Soares, MB Bonaldo, MF Casavant, TL Scheetz, TE Brownstein, MJ Usdin, TB Toshiyuki, S Carninci, P Prange, C Raha, SS Loquellano, NA Peters, GJ Abramson, RD Mullahy, SJ Bosak, SA McEwan, PJ McKernan, KJ Malek, JA Gunaratne, PH Richards, S Worley, KC Hale, S Garcia, AM Gay, LJ Hulyk, SW Villalon, DK Muzny, DM Sodergren, EJ Lu, XH Gibbs, RA Fahey, J Helton, E Ketteman, M Madan, A Rodrigues, S Sanchez, A Whiting, M Madan, A Young, AC Shevchenko, Y Bouffard, GG Blakesley, RW Touchman, JW Green, ED Dickson, MC Rodriguez, AC Grimwood, J Schmutz, J Myers, RM Butterfield, YSN Kryzywinski, MI Skalska, U Smailus, DE Schnerch, A Schein, JE Jones, SJM Marra, MA AF Strausberg, RL Feingold, EA Grouse, LH Derge, JG Klausner, RD Collins, FS Wagner, L Shenmen, CM Schuler, GD Altschul, SF Zeeberg, B Buetow, KH Schaefer, CF Bhat, NK Hopkins, RF Jordan, H Moore, T Max, SI Wang, J Hsieh, F Diatchenko, L Marusina, K Farmer, AA Rubin, GM Hong, L Stapleton, M Soares, MB Bonaldo, MF Casavant, TL Scheetz, TE Brownstein, MJ Usdin, TB Toshiyuki, S Carninci, P Prange, C Raha, SS Loquellano, NA Peters, GJ Abramson, RD Mullahy, SJ Bosak, SA McEwan, PJ McKernan, KJ Malek, JA Gunaratne, PH Richards, S Worley, KC Hale, S Garcia, AM Gay, LJ Hulyk, SW Villalon, DK Muzny, DM Sodergren, EJ Lu, XH Gibbs, RA Fahey, J Helton, E Ketteman, M Madan, A Rodrigues, S Sanchez, A Whiting, M Madan, A Young, AC Shevchenko, Y Bouffard, GG Blakesley, RW Touchman, JW Green, ED Dickson, MC Rodriguez, AC Grimwood, J Schmutz, J Myers, RM Butterfield, YSN Kryzywinski, MI Skalska, U Smailus, DE Schnerch, A Schein, JE Jones, SJM Marra, MA CA Mammalian Gene Collection MGC Pro TI Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID HUMAN GENOME; CLONES; RESOURCES; PROGRAMS AB The National Institutes of Health Mammalian Gene Collection (MGC) Program is a multiinstitutional effort to identify and sequence a cDNA clone containing a complete ORF for each human and mouse gene. ESTs were generated from libraries enriched for full-length cDNAs and analyzed to identify candidate full-ORF clones, which then were sequenced to high accuracy. The MGC has currently sequenced and verified the full ORF for a nonredundant set of >9,000 human and >6,000 mouse genes. Candidate full-ORF clones for an additional 7,800 human and 3,500 mouse genes also have been identified. All MGC sequences and clones are available without restriction through public databases and clone distribution networks (see http://mgc.nci.nih.gov). C1 NCI, NIH, Bethesda, MD 20892 USA. NHGRI, NIH, Bethesda, MD 20892 USA. Natl Ctr Biotechnol Informat, Natl Lib Med, NIH, Bethesda, MD 20894 USA. NCI, Ctr Bioinformat, Rockville, MD 20892 USA. Frederick Inc, SAIC, NCI, Frederick, MD 21702 USA. Invitrogen Corp, Carlsbad, CA 92008 USA. BD Biosci CLONTECH, Palo Alto, CA 94303 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Iowa, Iowa City, IA 52242 USA. NIMH, NIH, Cell Biol Lab, Bethesda, MD 20892 USA. RIKEN, Genome Sci Lab, Genom Sci Lab, Wako, Saitama 3510198, Japan. Lawrence Livermore Natl Lab, IMAGE Consortium, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Incyte Genom Inc, Palo Alto, CA 94304 USA. Agencourt Biosci Corp, Beverly, MA 01915 USA. Baylor Coll Med, Baylor Human Genome Sequencing Ctr, Dept Mol & Human Genet, Houston, TX 77030 USA. Inst Syst Biol, Seattle, WA 98103 USA. NIH, Intramural Sequencing Ctr, Gaithersburg, MD 20877 USA. Stanford Univ, Stanford Human Genome Ctr, Dept Genet, Sch Med, Palo Alto, CA 94304 USA. Univ British Columbia, Genome Sci Ctr, British Columbia Canc Agcy, Vancouver, BC V5Z 4E6, Canada. RP Strausberg, RL (reprint author), NCI, NIH, 31 Ctr Dr,Room 10A07, Bethesda, MD 20892 USA. RI Tang, Macy/B-9798-2014; Carninci, Piero/K-1568-2014; Schein, Jacquie/G-3674-2015; Jones, Steven/C-3621-2009; Marra, Marco/B-5987-2008; OI Carninci, Piero/0000-0001-7202-7243; McKernan, Kevin/0000-0002-3908-1122; Rubin, Gerald/0000-0001-8762-8703 FU NHGRI NIH HHS [U54 HG003273] NR 18 TC 1220 Z9 1335 U1 4 U2 62 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 DEC 24 PY 2002 VL 99 IS 26 BP 16899 EP 16903 DI 10.1073/pnas.242603899 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 630HN UT WOS:000180101600071 PM 12477932 ER PT J AU Lee, DR Choi, Y You, CY Lang, JC Haskel, D Srajer, G Metlushko, V Ilic, B Bader, SD AF Lee, DR Choi, Y You, CY Lang, JC Haskel, D Srajer, G Metlushko, V Ilic, B Bader, SD TI Magnetization reversal measurements in Gd/Fe multilayer antidot arrays by vector magnetometry using x-ray magnetic circular dichroism SO APPLIED PHYSICS LETTERS LA English DT Article ID PERMALLOY ARRAYS; DOMAIN FORMATION AB Fe K-edge x-ray magnetic circular dichroism (XMCD) was used as vector magnetometry to measure the magnetization rotation while field cycling Gd/Fe multilayer antidot arrays through a hysteresis loop. The measured XMCD hysteresis curves were then compared quantitatively with micromagnetic calculations to reconstruct the microscopic magnetization configurations. The best fit reveals the existence of three, types of characteristic domains: two that rotate coherently during magnetization reversal and one that is strongly pinned. The behavior is explained by a simple three-domain, energy model, including a phenomenological ansatz for a shape-induced demagnetization energy contribution. (C) 2002 American Institute of Physics. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Inha Univ, Dept Phys, Inchon 402751, South Korea. Univ Illinois, Dept Elect & Comp Engn, Chicago, IL 60607 USA. Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14858 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Lee, DR (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RI You, Chun-Yeol/B-1734-2010; Bader, Samuel/A-2995-2013; Ilic, Rob/N-1359-2014 OI You, Chun-Yeol/0000-0001-9549-8611; NR 13 TC 12 Z9 12 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 23 PY 2002 VL 81 IS 26 BP 4997 EP 4999 DI 10.1063/1.1532552 PG 3 WC Physics, Applied SC Physics GA 628VY UT WOS:000180018300035 ER PT J AU Han, WQ Zettl, A AF Han, WQ Zettl, A TI GaN nanorods coated with pure BN SO APPLIED PHYSICS LETTERS LA English DT Article ID BORON-NITRIDE NANOTUBES; CARBON NANOTUBES; NANOWIRES; GROWTH AB We report a method to efficiently synthesize gallium nitride (GaN) nanorods coated with insulating boron nitride (BN) layers. The GaN core is crystalline (with either a cubic zincblende or hexagonal wurtzite structure) and has diameters ranging from 10 to 85 nm and lengths up to 60 mum. The outer encapsulating BN shells with typical thicknesses less than 5 nm extend fully over, and adhere well to, the entire nanorod surface. (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 21 TC 58 Z9 61 U1 6 U2 18 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 DEC 23 PY 2002 VL 81 IS 26 BP 5051 EP 5053 DI 10.1063/1.1531836 PG 3 WC Physics, Applied SC Physics GA 628VY UT WOS:000180018300053 ER PT J AU Averitt, RD Taylor, AJ AF Averitt, RD Taylor, AJ TI Ultrafast optical and far-infrared quasiparticle dynamics in correlated electron materials SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Review ID TIME-DOMAIN SPECTROSCOPY; TEMPERATURE-GROWN GAAS; COLOSSAL-MAGNETORESISTANCE MANGANITES; TERAHERTZ PULSE SPECTROSCOPY; SUPERCONDUCTING THIN-FILMS; DOUBLE-EXCHANGE; FEMTOSECOND SPECTROSCOPY; CARRIER DYNAMICS; SPIN DYNAMICS; NONEQUILIBRIUM SUPERCONDUCTIVITY AB We review the application of ultrafast optical spectroscopy in the study of correlated electron materials. The emphasis is on all-optical pump-probe and optical pump-far-infrared probe experiments on (a) colossal-magnetoresistance manganites and (b) high-temperature superconductors. The experimental techniques are discussed followed by a brief review of ultrafast electron dynamics in conventional wide-band metals which serves as a starting point in understanding the dynamics in more complex metallic systems. In the half-metallic manganites, the quasiparticle dynamics in the ferromagnetic metallic state can be understood in terms of a dynamic transfer of spectral weight which is influenced by the lattice and spin degrees of freedom. For the high-temperature superconductors,, ultrafast quasiparticle dynamics are sensitive to the order parameter and superconducting pair recovery occurs on a picosecond timescale. These results show that, in general, ultrafast optical spectroscopy provides a sensitive method to probe the dynamics of quasiparticles at the Fermi level. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Averitt, RD (reprint author), Los Alamos Natl Lab, MST 10, Los Alamos, NM 87544 USA. NR 118 TC 141 Z9 143 U1 6 U2 60 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 23 PY 2002 VL 14 IS 50 BP R1357 EP R1390 AR PII S0953-8984(02)33363-0 DI 10.1088/0953-8984/14/50/203 PG 34 WC Physics, Condensed Matter SC Physics GA 716GL UT WOS:000185020400004 ER PT J AU John, KD Michalczyk, R Hernandez, G Green, JC Martin, RL Baker, RT Sattelberger, AP AF John, KD Michalczyk, R Hernandez, G Green, JC Martin, RL Baker, RT Sattelberger, AP TI The remarkable structure and dynamics of tris(allyl)rhodium and -iridium as determined by theory and experiment SO ORGANOMETALLICS LA English DT Article ID M = RH; ALLYL COMPLEXES; REACTIVITY; CHEMISTRY; CHROMIUM; LIGANDS; SILICA; ENERGY; METAL; IR AB The molecular geometries and electronic structures of M(eta(3)-allyl)(3) [M = Rh, Ir] have been calculated by both hybrid and gradient-corrected density functional theory (DFT). Hybrid DFT (B3LYP) calculations predict a global minimum of C, symmetry for both species. For Ir(allyl)(3) a local minimum of C-3h symmetry was also located ca. 3 kcal/mol above the C-1 ground state. These two minima are related by a a-allyl transition state with a barrier of ca. 21 kcal/mol. The C-1 symmetry global minimum contains two basal allyls and an apical. allyl ligand that can rotate about its axis through a concerted motion involving two distinct transition states of C-s symmetry (activation energy DeltaE(double dagger) similar or equal to 10 kcal/mol). Variable-temperature C-13 NMR analysis of the Ir analogue confirms the C, ground state and validates the predicted activation energy experimentally (9.9 +/- 1.4 kcal/mol). Additional evidence for the C-1 ground state comes from the good agreement of the calculated B3LYP Raman spectrum with experiment. Dynamic H-1 and C-13 NMR spectra of Rh(allyl)(3) provide evidence for three different fluxional processes, corresponding to the three transition states discussed above. Finally, the electronic structure of both complexes has been studied both experimentally and theoretically using photoelectron spectroscopy (PES) and gradient-corrected DFT calculations using the C-1 symmetry geometry obtained from hybrid DFT methods. C1 Los Alamos Natl Lab, Div Chem, Los Alamos Catalysis Initiat, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Univ Oxford, Inorgan Chem Lab, Oxford OX1 3QR, England. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Chem, Los Alamos Catalysis Initiat, MS J514, Los Alamos, NM 87545 USA. OI Michalczyk, Ryszard/0000-0001-8839-6473; John, Kevin/0000-0002-6181-9330 NR 31 TC 4 Z9 4 U1 1 U2 3 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 DEC 23 PY 2002 VL 21 IS 26 BP 5757 EP 5766 DI 10.1021/om020632p PG 10 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 627KN UT WOS:000179932500009 ER PT J AU Chen, JB Young, VG Angelici, RJ AF Chen, JB Young, VG Angelici, RJ TI Syntheses, structures, and reactions of eta(6) complexes of iridathiabenzene with chromium, molybdenum, and tungsten carbonyls SO ORGANOMETALLICS LA English DT Article ID SULFUR BOND-CLEAVAGE; THIOPHENE COORDINATION; METAL-COMPLEXES; HOMOGENEOUS HYDRODESULFURIZATION; REACTIVITY; BENZOTHIOPHENE; CHEMISTRY; DESULFURIZATION; HYDROGENATION; LIGANDS AB The iridathiabenzene analogues [eta(6)-Cp*lr(C,S-2,5-Me2T)M(CO)(3), where M = Cr (3), Mo (5), W (7), of (eta(6)-arene)M(CO)(3) are prepared from M(CO)(3)(NCMe)(3) and Cp*Ir(C,S-2,5-Me2T) (2), where C,S-2,5-Me2T is ring-opened 2,5-dimethylthiophene. The high reactivity and coordination flexibility of the eta(6)-Cp*Ir(C,S-2,5-Me2T) ligand leads to a variety of products upon reaction with phosphine ligands. The reaction of 3 with PEt3 leads to PEt3 adduct formation at the Ir in the product [eta(5)-Cp*Ir(PEt3)(C,S-2,5-Me2T)] [Cr(CO)(3)] (17). On the other hand, reaction of the analogous tungsten complex 7 with PEt3 yields the adduct [eta(4)-Cp*Ir(C,S-2,5-Me2T)]W(CO)(2)(PEt3)(mu-CO) (19), in which PEt3 adds to the W atom. These and other studies show that the iridathiabenzene ligand is capable of coordination to Cr, Mo, or W through one, four, five, or six of its ring atoms. When 7 is reacted with CF3SO3H, protonation occurs at the tungsten, as occurs in the protonation of the analogous arene complex (,eta(6)-C6Me6)W(CO)(3). -Structures of four of the complexes were established by X-ray studies. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Chinese Acad Sci, Shanghai Inst Organ Chem, Shanghai 200032, Peoples R China. RP Angelici, RJ (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. NR 52 TC 7 Z9 7 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD DEC 23 PY 2002 VL 21 IS 26 BP 5951 EP 5961 DI 10.1021/om020636u PG 11 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 627KN UT WOS:000179932500032 ER PT J AU Kiplinger, JL Morris, DE Scott, BL Burns, CJ AF Kiplinger, JL Morris, DE Scott, BL Burns, CJ TI Convenient synthesis, structure, and reactivity of (C5Me5)U(CH2C6H5)(3): a simple strategy for the preparation of monopentamethylcyclopentadienyl uranium(IV) complexes SO ORGANOMETALLICS LA English DT Article ID ORGANO-METALLIC COMPOUNDS; MOLECULAR-STRUCTURE; SUPPORTED ORGANOACTINIDES; SOLVENT PURIFICATION; CRYSTAL-STRUCTURE; CHEMISTRY; DERIVATIVES; DYNAMICS; HYDROCARBYLS; HYDRIDES AB A high-yield one-pot synthesis of (C5Me5)U(CH2C6H5)(3) has been developed and applied to the synthesis of a new organouranium complex possessing a (pentamethyleyelopentadienyl)bis(cyclopentadienyl) ligand framework, (C5Me5)(C5H5)(2)U(CH2C6H5). Both complexes have been structurally characterized. We also report herein an improved and safer synthesis for the popular uranium starting material UCl4. C1 Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP Kiplinger, JL (reprint author), Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RI Morris, David/A-8577-2012; Kiplinger, Jaqueline/B-9158-2011; Scott, Brian/D-8995-2017 OI Kiplinger, Jaqueline/0000-0003-0512-7062; Scott, Brian/0000-0003-0468-5396 NR 53 TC 61 Z9 61 U1 4 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD DEC 23 PY 2002 VL 21 IS 26 BP 5978 EP 5982 DI 10.1021/om0206610 PG 5 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 627KN UT WOS:000179932500035 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 Anderson, EW Arnoud, Y Avila, C Babintsev, VV Babukhadia, L Bacon, TC Baden, A Baldin, B Balm, PW Banerjee, S Barberis, E Baringer, P Barreto, J Bartlett, JF Bassler, U Bauer, D 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 Bolton, TA 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 Claes, D Clark, AR Coney, L Connolly, B Cooper, WE Coppage, D Crepe-Renaudin, S Cummings, MAC Cutts, D Davis, GA De, K de Jong, SJ 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 Fein, D Ferbel, T Filthaut, F Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Fox, H 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 Goncharov, PI Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N 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 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 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 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 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 Mutaf, YD Nagy, E Nang, F Narain, M Narasimham, VS Naumann, NA Neal, HA Negret, JP Nomerotski, A Nunnemann, T O'Neil, D Oguri, V Olivier, B Oshima, N Padley, P Papageorgiou, K Parashar, N Partridge, R Parua, N Patwa, A Peters, O Petroff, P Piegaia, R Pope, BG Popkov, E Prosper, HB Protopopescu, S Przybycien, MB Qian, J Raja, R Rajagopalan, S 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 Shabalina, E Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Sirotenko, V Slattery, P 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 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 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 Anderson, EW Arnoud, Y Avila, C Babintsev, VV Babukhadia, L Bacon, TC Baden, A Baldin, B Balm, PW Banerjee, S Barberis, E Baringer, P Barreto, J Bartlett, JF Bassler, U Bauer, D 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 Bolton, TA 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 Claes, D Clark, AR Coney, L Connolly, B Cooper, WE Coppage, D Crepe-Renaudin, S Cummings, MAC Cutts, D Davis, GA De, K de Jong, SJ 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 Fein, D Ferbel, T Filthaut, F Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Fox, H 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 Goncharov, PI Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N 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 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 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 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 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 Mutaf, YD Nagy, E Nang, F Narain, M Narasimham, VS Naumann, NA Neal, HA Negret, JP Nomerotski, A Nunnemann, T O'Neil, D Oguri, V Olivier, B Oshima, N Padley, P Papageorgiou, K Parashar, N Partridge, R Parua, N Patwa, A Peters, O Petroff, P Piegaia, R Pope, BG Popkov, E Prosper, HB Protopopescu, S Przybycien, MB Qian, J Raja, R Rajagopalan, S 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 Shabalina, E Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Sirotenko, V Slattery, P 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 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 Zanabria, M Zhang, X Zheng, H Zhou, B Zhou, Z Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A CA D0 Collaboration TI Search for the production of single sleptons through R-parity violation in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID TEVATRON RUN-II; HADRON COLLIDERS; SUPERSYMMETRY; PYTHIA-5.7; STATES; WEAK AB We report the first search for supersymmetric particles via s-channel production and decay of smuons or muon sneutrinos at hadronic colliders. The data for the two-muon and two-jets final states were collected by the D0 experiment and correspond to an integrated luminosity of 94+/-5 pb(-1). Assuming that R parity is violated via the single coupling lambda(211)('), the number of candidate events is in agreement with expectation from the standard model. Exclusion contours are given in the (m(0),m(1/2)) and (m((χ) over bar),m((ν) over bar)) planes for lambda(211)(')=0.09, 0.08, and 0.07. C1 Joint Inst Nucl Res, Dubna, Russia. Univ Buenos Aires, Buenos Aires, DF, Argentina. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. Univ Estado Rio de Janeiro, Rio De Janeiro, Brazil. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Los Andes, Bogota, Colombia. Charles Univ, Ctr Particle Phys, Prague, Czech Republic. Acad Sci Czech Republ, Inst Phys, Ctr Particle Phys, Prague, Czech Republic. Univ San Francisco Quito, Quito, Ecuador. Univ Grenoble 1, CNRS, IN2P3, Inst Nucl Sci, Grenoble, France. Univ Mediterranee, CNRS, IN2P3, CPPM, Marseille, France. CNRS, IN2P3, Lab Accelerateur Lineaire, F-91405 Orsay, France. Univ Paris 06, LPNHE, Paris, France. Univ Paris 07, CNRS, IN2P3, Paris, France. CEA, 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. NIKHEF H, FOM Inst, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, NIKHEF, Amsterdam, Netherlands. Univ Nijmegen, NIKHEF, Nijmegen, Netherlands. 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 & Med, London, England. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, 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), Joint Inst Nucl Res, Dubna, Russia. RI Chekulaev, Sergey/O-1145-2015; Canelli, Florencia/O-9693-2016; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Nomerotski, Andrei/A-5169-2010; Shivpuri, R K/A-5848-2010; Oguri, Vitor/B-5403-2013; Gutierrez, Phillip/C-1161-2011; Dudko, Lev/D-7127-2012; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Yip, Kin/D-6860-2013; Kim, Sun Kee/G-2042-2015 OI Canelli, Florencia/0000-0001-6361-2117; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kim, Sun Kee/0000-0002-0013-0775 NR 21 TC 10 Z9 10 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 DEC 23 PY 2002 VL 89 IS 26 AR 261801 DI 10.1103/PhysRevLett.89.261801 PG 6 WC Physics, Multidisciplinary SC Physics GA 626NC UT WOS:000179878200006 PM 12398658 ER PT J AU Audebert, P Shepherd, R Fournier, KB Peyrusse, O Price, D Lee, R Springer, P Gauthier, JC Klein, L AF Audebert, P Shepherd, R Fournier, KB Peyrusse, O Price, D Lee, R Springer, P Gauthier, JC Klein, L TI Heating of thin foils with a relativistic-intensity short-pulse laser SO PHYSICAL REVIEW LETTERS LA English DT Article ID CONTROLLED PREFORMED PLASMA; SOLID-DENSITY; STREAK-CAMERA; FEMTOSECOND; SPECTROSCOPY; SIMULATION; ELECTRONS; ALUMINUM; TARGETS; DRIVEN AB K-shell x-ray spectroscopy of sub-100 nm Al foils irradiated by high contrast, spatially uniform, 150 fs, Ilambda(2)=2x10(18) W mum(2)/cm(2), laser pulses is obtained with 500 fs time resolution. Two distinct phases occur: At less than or equal to500 fs a broad feature comparable to the resonance transitions occurs due to satellites, and at greater than or equal to500 fs the resonance transitions dominate. Initial satellites arise from a large area, high density, low temperature (similar to100 eV) plasma created by fast electrons. Thus, contrary to predictions, a short, high intensity laser incident on a thin foil does not create a uniform, hot dense plasma. C1 Univ Paris 06, Ecole Polytech, CEA, CNRS,UMR 7605,LULI, F-91128 Palaiseau, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Comm Energie Atom, F-91680 Bruyeres Le Chatel, France. Howard Univ, Dept Phys & Astron, Washington, DC 20059 USA. RP Audebert, P (reprint author), Univ Paris 06, Ecole Polytech, CEA, CNRS,UMR 7605,LULI, F-91128 Palaiseau, France. RI Frank, David/E-8213-2012 NR 34 TC 44 Z9 44 U1 1 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 DEC 23 PY 2002 VL 89 IS 26 AR 265001 DI 10.1103/PhysRevLett.89.265001 PG 4 WC Physics, Multidisciplinary SC Physics GA 626NC UT WOS:000179878200023 PM 12484827 ER PT J AU Bardayan, DW Batchelder, JC Blackmon, JC Champagne, AE Davinson, T Fitzgerald, R Hix, WR Iliadis, C Kozub, RL Ma, Z Parete-Koon, S Parker, PD Shu, N Smith, MS Woods, PJ AF Bardayan, DW Batchelder, JC Blackmon, JC Champagne, AE Davinson, T Fitzgerald, R Hix, WR Iliadis, C Kozub, RL Ma, Z Parete-Koon, S Parker, PD Shu, N Smith, MS Woods, PJ TI Strength of the F-18(p,alpha)O-15 resonance at E-c.m.=330 keV SO PHYSICAL REVIEW LETTERS LA English DT Article ID POSITRON-ANNIHILATION; NOVAE; NUCLEOSYNTHESIS; ENERGIES AB Production of the radioisotope F-18 in novae is severely constrained by the rate of the F-18(p,alpha)O-15 reaction. A resonance at E-c.m.=330 keV may strongly enhance the F-18(p,alpha)O-15 reaction rate, but its strength has been very uncertain. We have determined the strength of this important resonance by measuring the F-18(p,alpha)O-15 cross section on and off resonance using a radioactive F-18 beam at the ORNL Holifield Radioactive Ion Beam Facility. We find that its resonance strength is 1.48+/-0.46 eV, and that it dominates the F-18(p,alpha)O-15 reaction rate over a significant range of temperatures characteristic of ONeMg novae. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Oak Ridge Associated Univ, INIRIB, Oak Ridge, TN 37831 USA. Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Univ Edinburgh, Dept Phys & Astron, Edinburgh EH9 3JZ, Midlothian, Scotland. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Tennessee Technol Univ, Dept Phys, Cookeville, TN 38505 USA. Yale Univ, AW Wright Nucl Struct Lab, New Haven, CT 06520 USA. Chinese Inst Atom Energy, Beijing 102413, Peoples R China. RP Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RI Hix, William/E-7896-2011; Fitzgerald, Ryan/H-6132-2016 OI Hix, William/0000-0002-9481-9126; NR 23 TC 65 Z9 65 U1 0 U2 6 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 DEC 23 PY 2002 VL 89 IS 26 AR 262501 DI 10.1103/PhysRevLett.89.262501 PG 4 WC Physics, Multidisciplinary SC Physics GA 626NC UT WOS:000179878200007 PM 12484811 ER PT J AU Gu, JY You, CY Jiang, JS Pearson, J Bazaliy, YB Bader, SD AF Gu, JY You, CY Jiang, JS Pearson, J Bazaliy, YB Bader, SD TI Magnetization-orientation dependence of the superconducting transition temperature in the ferromagnet-superconductor-ferromagnet system: CuNi/Nb/CuNi SO PHYSICAL REVIEW LETTERS LA English DT Article ID MULTILAYERS; BILAYERS AB The superconducting critical temperature (T-c) of ferromagnet-superconductor-ferromagnet systems has been predicted to exhibit a dependence on the magnetization orientation of the ferromagnetic layers such that T-c(AP)>T-c(P) for parallel (P) and antiparallel (AP) configurations of the two ferromagnetic layers. We have grown CuNi/Nb/CuNi films via magnetron sputtering and confirmed the theoretical prediction by measuring the resistance of the system as a function of temperature and magnetic field. We find an similar to25% resistance drop occurs near T-c in Cu0.47Ni0.53(5 nm)/Nb(18)/CuNi(5) when the two CuNi layers change their magnetization directions from parallel to antiparallel, whereas there is no corresponding resistance change in the normal state. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Gu, JY (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI You, Chun-Yeol/B-1734-2010; Bader, Samuel/A-2995-2013 OI You, Chun-Yeol/0000-0001-9549-8611; NR 24 TC 215 Z9 218 U1 1 U2 20 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 DEC 23 PY 2002 VL 89 IS 26 AR 267001 DI 10.1103/PhysRevLett.89.267001 PG 4 WC Physics, Multidisciplinary SC Physics GA 626NC UT WOS:000179878200047 PM 12484851 ER PT J AU Kaganovich, ID AF Kaganovich, ID TI Anomalous capacitive sheath with deep radio-frequency electric-field penetration SO PHYSICAL REVIEW LETTERS LA English DT Article ID PRESSURE RF DISCHARGE; GLOW-DISCHARGES AB A novel nonlinear effect of anomalously deep penetration of an external radio-frequency electric field into a plasma is described. A self-consistent kinetic treatment reveals a transition region between the sheath and the plasma. Because of the electron velocity modulation in the sheath, bunches in the energetic electron density are formed in the transition region adjacent to the sheath. The width of the region is of order V-T/omega, where V-T is the electron thermal velocity, and omega is the frequency of the electric field. The presence of the electric field in the transition region results in a collisionless cooling of the energetic electrons and an additional heating of the cold electrons. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kaganovich, ID (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 17 TC 62 Z9 62 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 DEC 23 PY 2002 VL 89 IS 26 AR 265006 DI 10.1103/PhysRevLett.89.265006 PG 4 WC Physics, Multidisciplinary SC Physics GA 626NC UT WOS:000179878200028 PM 12484832 ER PT J AU Kudin, KN Scuseria, GE Martin, RL AF Kudin, KN Scuseria, GE Martin, RL TI Hybrid density-functional theory and the insulating gap of UO2 SO PHYSICAL REVIEW LETTERS LA English DT Article ID CRYSTAL-STRUCTURES; URANIUM-OXIDES; BAND-STRUCTURE; HARTREE-FOCK; EXCHANGE; ENERGY; PHOTOEMISSION; ELECTRONS; ACTINIDES AB We report the first calculations carried out with a periodic boundary condition code capable of examining hybrid density-functional theory (DFT) for f-element solids. We apply it to the electronic structure of the traditional Mott insulator UO2, and find that it correctly yields an antiferromagnetic insulator as opposed to the ferromagnetic metal predicted by the local spin density and generalized gradient approximations. The gap, density of states, and optimum lattice constant are all in good agreement with experiment. We stress that this results from the functional and the variational principle alone. We compare our results with the more traditional approximations. C1 Rice Univ, Dept Chem, Houston, TX 77005 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Rice Univ, Dept Chem, POB 1892, Houston, TX 77005 USA. RI Kudin, Konstantin/A-7723-2008; Scuseria, Gustavo/F-6508-2011 NR 45 TC 184 Z9 185 U1 5 U2 45 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 DEC 23 PY 2002 VL 89 IS 26 AR 266402 DI 10.1103/PhysRevLett.89.266402 PG 4 WC Physics, Multidisciplinary SC Physics GA 626NC UT WOS:000179878200038 PM 12484842 ER PT J AU Yu, HG Muckerman, JT AF Yu, HG Muckerman, JT TI Quantum dynamics of the photoinitiated unimolecular dissociation of HOCO SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CO REACTANT COMPLEX; FILTER-DIAGONALIZATION; TRANS-HOCO; OH+CO->CO2+H REACTION; MAGNETIC-RESONANCE; PLANAR ACETYLENE; CO2-HI COMPLEXES; TIME; OH; SPECTROSCOPY AB The photodissociation dynamics of HOCO in the overtone nu(OH)=3 are studied using a time-dependent wave packet dynamics approach. The dynamics calculations are carried out using a four-dimensional planar model in which the terminal C=O bond (spectator) is fixed at its equilibrium bond distance in the trans-HOCO conformer based on an empirical potential energy surface for HOCO fit to accurate ab initio calculations of the stationary point energies. The branching fraction into the H+CO2 products, and the resonance states associated with nu(OH)=3 are investigated in detail. (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, Upton, NY 11973 USA. RI Muckerman, James/D-8752-2013; Yu, Hua-Gen/N-7339-2015 NR 52 TC 24 Z9 24 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 22 PY 2002 VL 117 IS 24 BP 11139 EP 11145 DI 10.1063/1.1522711 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 624RD UT WOS:000179774000021 ER PT J AU Manaa, MR Ross, AJ Martin, F Crozet, P Lyyra, AM Li, L Amiot, C Bergeman, T AF Manaa, MR Ross, AJ Martin, F Crozet, P Lyyra, AM Li, L Amiot, C Bergeman, T TI Spin-orbit interactions, new spectral data, and deperturbation of the coupled b (3)Pi(u) and A (1)Sigma(+)(u) states of K-2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TRIPLE-RESONANCE SPECTROSCOPY; LASER-INDUCED FLUORESCENCE; CS-2 ULTRACOLD MOLECULES; OPTICAL DOUBLE-RESONANCE; POLARIZATION SPECTROSCOPY; INTERCOMBINATION BANDS; THEORETICAL TREATMENT; ELECTRONIC STATES; 3-PI-U STATES; EXCITED RB-2 AB We report calculations of the spin-orbit energy as a function of internuclear distance R within the b (3)Pi(u) state of K-2, and between the b (3)Pi(0u) and A (1)Sigma(u)(+) states, together with new spectroscopic data on the b state and previously unpublished data on the A state. Both the new data and previous data are fitted to Hamiltonian parameters using the discrete variable representation (DVR) method. The DVR matrix includes nonrelativistic Born-Oppenheimer potentials and spin-orbit interactions, which are scaled to match the known asymptotic limits and to best fit the experimental data. We report fitted Dunham coefficients that yield the A and b state potentials by means of the Rydberg-Klein-Rees method. These parameters thus take into account second-order spin-orbit perturbation shifts (from the vibrational levels of these two states) which are normally not considered in band-by-band fits to spectroscopic data. (C) 2002 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Energet Mat Ctr, Livermore, CA 94551 USA. Univ Lyon 1, Spectrometrie Ion & Mol Lab, CNRS, UMR 5579, F-69622 Villeurbanne, France. Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. Tsing Hua Univ, Dept Phys, Beijing 10084, Peoples R China. Tsing Hua Univ, Key Lab Atom & Mol Nanosci, Beijing 10084, Peoples R China. CNRS 2, Aime Cotton Lab, F-91405 Orsay, France. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. RP Manaa, MR (reprint author), Lawrence Livermore Natl Lab, Energet Mat Ctr, L-282, Livermore, CA 94551 USA. NR 70 TC 40 Z9 40 U1 0 U2 9 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 22 PY 2002 VL 117 IS 24 BP 11208 EP 11215 DI 10.1063/1.1522716 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 624RD UT WOS:000179774000029 ER PT J AU Viecelli, JA Glosli, JN AF Viecelli, JA Glosli, JN TI Carbon cluster coagulation and fragmentation kinetics in shocked hydrocarbons SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DETONATION PROPERTIES; MOLECULAR-DYNAMICS; SYNTHETIC URANUS; PLANETARY ICES; TEMPERATURE; PRESSURE; METHANE; EXPLOSIVES; PARTICLES; DISSOCIATION AB Molecular dynamics simulations of the dissociation of methane, ethylene, and benzene at 50 GPa show that thermally activated carbon-carbon bond breaking produces a stationary n(-5/2) distribution of short-lived n-atom carbon chains. Chain fragmentation rates follow an Arrhenius law in temperature, and the fraction of carbon existing as small chains increases with increasing temperature, ultimately approaching 1 at some critical temperature. Mean-field coagulation theory with added fragmentation terms yields the stationary n(-5/2) distribution and shows that the rate of carbon coagulation to bulk material slows down with increasing temperature, approaching zero at the critical temperature. (C) 2002 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM viecelli1@llnl.gov NR 33 TC 9 Z9 9 U1 1 U2 10 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 DEC 22 PY 2002 VL 117 IS 24 BP 11352 EP 11358 DI 10.1063/1.1522395 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 624RD UT WOS:000179774000046 ER PT J AU Agarwal, R Prall, BS Rizvi, AH Yang, M Fleming, GR AF Agarwal, R Prall, BS Rizvi, AH Yang, M Fleming, GR TI Two-color three pulse photon echo peak shift spectroscopy (vol 116, pg 6243, 2002) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Correction C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Agarwal, R (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 1 TC 1 Z9 1 U1 1 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 DEC 22 PY 2002 VL 117 IS 24 BP 11404 EP 11404 DI 10.1063/1.1521149 PG 1 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 624RD UT WOS:000179774000052 ER PT J AU Ofman, L Gary, SP Vinas, A AF Ofman, L Gary, SP Vinas, A TI Resonant heating and acceleration of ions in coronal holes driven by cyclotron resonant spectra SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE ion cyclotron waves; heating; coronal holes; hybrid simulations; solar wind; minor ions ID SPEED SOLAR-WIND; MODEL; WAVES; CONSTRAINTS; ANISOTROPY; UVCS AB Recent observations and models suggest that the resonant absorption of ion cyclotron waves heats and accelerates the ions in the solar wind. Velocity distributions of minor ions derived from SOHO Ultraviolet Cronagraph Spectrometer (UVCS) observations in coronal holes indicate that the minor ion temperature anisotropy is T-perpendicular to/T-parallel to>10 and that outflow speeds are higher than those of the solar wind protons. Here one-dimensional hybrid simulations of initially homogeneous, collisionless plasmas are used to study a model of coronal plasmas including kinetic protons, a tenuous component of oxygen ions, and massless fluid electrons. Spectra of ion cyclotron resonant Alfven waves are imposed on the system to study the resultant heating of both ion species. We investigate the effects of various power spectra of the form f(-1) or f(-5/3) and vary the input frequency range. We find that the ion heating strongly depends on the power contained in the frequency range of the input spectrum that can resonate with the ions. The minor O5+ ions are easily heated and become anisotropic due to various forms of the spectra. The protons remain nearly isotropic and are weakly heated in most cases in this study. We investigate the self-consistent fluctuation spectrum generated by the response of the ions and the non-Maxwellian features in the velocity distribution. C1 Catholic Univ Amer, Washington, DC 20064 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Catholic Univ Amer, Washington, DC 20064 USA. EM Leon.Ofman@gsfc.nasa.gov; pgary@lanl.gov; vinas@unamuno.gsfc.nasa.gov NR 31 TC 37 Z9 38 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 21 PY 2002 VL 107 IS A12 AR 1461 DI 10.1029/2002JA009432 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 650AR UT WOS:000181240600002 ER PT J AU Zhang, T Chu, PK Fu, RKY Brown, IG AF Zhang, T Chu, PK Fu, RKY Brown, IG TI Plasma transport in magnetic duct filter SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID VACUUM-ARC PLASMAS; CHARGE-STATE DISTRIBUTIONS; CATHODIC ARC; FIELDS AB A cathodic arc plasma source equipped with a curved magnetic duct to filter macro-particles was used to study plasma transport through the duct. The optimal duct bias, at which the magnetic duct produces the maximum plasma output, for titanium cathodic arc plasma at 50, 100 and 150 A arc current was determined and the parametric effects of the arc current and guiding magnetic field on the optimal duct bias were investigated. The optimal bias decreased as the guiding magnetic field increased from 100 to 400 G and was almost independent of the guiding magnetic field when it was between 400 and 600 G, the upper limit for our equipment. The optimal duct bias at 400 G guiding magnetic field decreased with increasing arc current: Our results indicate that the optimal duct bias is related not only to the structure of the plasma source, but is also influenced by many other factors including cathode material and other plasma properties. 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, Dept Mat Sci, 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 9 Z9 9 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD DEC 21 PY 2002 VL 35 IS 24 BP 3176 EP 3180 AR PII S0022-3727(02)38203-2 DI 10.1088/0022-3727/35/24/305 PG 5 WC Physics, Applied SC Physics GA 633EW UT WOS:000180270400005 ER PT J AU Preece, RD Briggs, MS Giblin, TW Mallozzi, RS Pendleton, GN Paciesas, WS Band, DL AF Preece, RD Briggs, MS Giblin, TW Mallozzi, RS Pendleton, GN Paciesas, WS Band, DL TI On the consistency of gamma-ray burst spectral indices with the synchrotron shock model SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; radiation mechanisms : nonthermal; shock waves ID BATSE OBSERVATIONS; X-RAY; EMISSION MECHANISMS; MAGNETIC-FIELDS; INTERNAL SHOCKS; FIREBALL MODEL; GRB 970508; EVOLUTION; SPECTROSCOPY; CONSTRAINTS AB The current scenario for gamma-ray bursts (GRBs) involves internal shocks for the prompt GRB emission phase and external shocks for the afterglow phase. Assuming optically thin synchrotron emission from isotropically distributed energetic shocked electrons, GRB spectra observed with a low-energy power-law spectral index greater than -2/3 (for positive photon number indices E-alpha) indicate a problem with this model. For spectra that do not violate this condition, additional tests of the shock model can be made by comparing the low-and high-energy spectral indices, on the basis of the model's assertion that synchrotron emission from a single power-law distribution of electrons is responsible for both the low-energy and the high-energy power-law portions of the spectra. We find in most cases that the inferred relationship between the two spectral indices of observed GRB spectra is inconsistent with the constraints from the simple optically thin synchrotron shock emission model. In this sense, the prompt burst phase is different from the afterglow phase, and this difference may be related to anisotropic distributions of particles or to their continual acceleration in shocks during the prompt phase. C1 Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. OI Preece, Robert/0000-0003-1626-7335 NR 45 TC 63 Z9 64 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 DEC 20 PY 2002 VL 581 IS 2 BP 1248 EP 1255 DI 10.1086/344252 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 627DA UT WOS:000179914300040 ER PT J AU Jimenez-Garate, MA Raymond, JC Liedahl, DA AF Jimenez-Garate, MA Raymond, JC Liedahl, DA TI The structure and X-ray recombination emission of a centrally illuminated accretion disk atmosphere and corona SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; atomic processes; instabilities; line : formation; X-rays : binaries ID ACTIVE GALACTIC NUCLEI; HELIUM-LIKE IONS; GRATING SPECTROMETER; THERMAL-INSTABILITY; PHOTOELECTRIC ABSORPTION; MAGNETIC RECONNECTION; PHOTOIONIZED PLASMA; VERTICAL STRUCTURE; LINE-INTENSITIES; CROSS-SECTIONS AB We model an accretion disk atmosphere and corona photoionized by a central X-ray continuum source. We calculate the opacity and one-dimensional radiation transfer for an array of disk radii to obtain the two-dimensional structure of the disk and its X-ray recombination emission. The atmospheric structure is extremely insensitive to the viscosity alpha. We find a feedback mechanism between the disk structure and the central illumination, which expands the disk and increases the solid angle subtended by the atmosphere. We apply the model to the disk of a neutron star X-ray binary. The model is in agreement with the similar to12degrees disk half-angle measured from optical light curves. We map the temperature, density, and ionization structure of the disk, and we simulate high-resolution spectra expected from the Chandra and XMM-Newton grating spectrometers. X-ray emission lines from the disk atmosphere are detectable, especially for high-inclination binary systems. The grating observations of two classes of X-ray binary systems already reveal important spectral similarities with our models. The model spectrum is dominated by double-peaked lines of H-like and He-like ions plus weak Fe L. The line flux is proportional to the luminosity and is dominated by the outer radii. Species with a broad range of ionization levels coexist at each radius, from Fe XXVI in the hot corona to C VI at the base of the atmosphere. The line spectrum is very sensitive to the temperature, ionization, and emission measure of each atmospheric layer, and it probes the heating mechanisms in the disk. We assume a hydrostatic disk dominated by gas pressure, in thermal balance, and in ionization equilibrium. As boundary conditions, we take a Compton temperature corona and an underlying Shakura-Sunyaev disk. The choice of thermally stable solutions strongly affects the spectrum since a thermal instability is present in the regime where X-ray recombination emission is most intense. C1 MIT, Ctr Space Res, Cambridge, MA 02139 USA. Ctr Astrophys, Cambridge, MA 02138 USA. Lawrence Livermore Natl Lab, Dept Phys & Adv Technol, Livermore, CA 94550 USA. RP MIT, Ctr Space Res, 70 Vassar St,NE80-6009, Cambridge, MA 02139 USA. EM mario@alum.mit.edu; raymond@cfa.harvard.edu; liedahl1@llnl.gov NR 88 TC 36 Z9 36 U1 1 U2 6 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 DEC 20 PY 2002 VL 581 IS 2 BP 1297 EP 1327 PN 1 PG 31 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 627DA UT WOS:000179914300046 ER PT J AU Roe, HG de Pater, I Macintosh, BA McKay, CP AF Roe, HG de Pater, I Macintosh, BA McKay, CP TI Titan's clouds from Gemini and Keck adaptive optics imaging SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : solar system; instrumentation : adaptive optics; planets and satellites : individual (Titan) ID SATURN SYSTEM; FIRST LIGHT; ATMOSPHERE; IMAGES; HST; TROPOSPHERE; TELESCOPE; ASYMMETRY; SURFACE; MODELS AB Using adaptive optics on the Gemini and Keck II telescopes, we found a thin haze and discrete clouds in Titan's south polar troposphere. The discrete clouds vary on timescales of a few hours. We propose a seasonal mechanism to explain the formation of this spring polar tropospheric haze. Assuming that the clouds are located in or above the haze, we suggest that convection within this haze layer triggers methane condensation; subsequent latent heat release leads to vigorous convection and formation of transient clouds. Our results have significant implications for planning the Cassini mission flybys of Titan. C1 Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Roe, HG (reprint author), Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. NR 39 TC 93 Z9 93 U1 0 U2 4 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 DEC 20 PY 2002 VL 581 IS 2 BP 1399 EP 1406 DI 10.1086/344403 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 627DA UT WOS:000179914300053 ER PT J AU Liu, CX Gorby, YA Zachara, JM Fredrickson, JK Brown, CF AF Liu, CX Gorby, YA Zachara, JM Fredrickson, JK Brown, CF TI Reduction kinetics of Fe(III), Co(III), U(VI) Cr(VI) and Tc(VII) in cultures of dissimilatory metal-reducing bacteria SO BIOTECHNOLOGY AND BIOENGINEERING LA English DT Article DE kinetics; metal; metal-reducing bacteria; bio-reduction; biogenic precipitate ID MICROBIAL REDUCTION; SHEWANELLA-PUTREFACIENS; BIOCHEMICAL NETWORKS; ELECTRON-TRANSFER; AQUEOUS-SOLUTIONS; URANIUM; IRON; TRANSPORT; MANGANESE; OXIDE AB The reduction kinetics of Fe(III)citrate, Fe(III)NTA, Co(III)EDTA(-), U(VI)O-2(2+), Cr(VI)O-4(2-), and Tc(VII)O-4(-) were studied in cultures of dissimilatory metal reducing bacteria (DMRB): Shewanella alga strain BrY, Shewanella putrefaciens strain CN32, Shewanella oneidensis strain MR-1, and Geobacter metallireducens strain GS-15. Reduction rates were metal specific with the following rate trend: Fe(III)citrate : Fe(III)NTA > Co(III)EDTA(-) much greater than UO22+ > CrO42- > TcO4-, except for CrO42- when H-2 was used as electron donor. The metal reduction rates were also electron donor dependent with faster rates observed for H-2 than lactate(-) for all Shewanella species despite higher initial lactate (10 mM) than H-2 (0.48 mM). The bioreduction of CrO42- was anomalously slower compared to the other metals with H-2 as an electron donor relative to lactate and reduction ceased before all the CrO42- had been reduced. Transmission electron microscopic (TEM) and energy-dispersive spectroscopic (EDS) analyses performed on selected solids at experiment termination found precipitates of reduced U and Tc in association with the outer cell membrane and in the periplasm of the bacteria. The kinetic rates of metal reduction were correlated with the precipitation of reduced metal phases and their causal relationship discussed. The experimental rate data were well described by a Monod kinetic expression with respect to the electron acceptor for all metals except CrO42-, for which the Monod model had to be modified to account for incomplete reduction. However, the Monod models became statistically over-parametrized, resulting in large uncertainties of their parameters. A first-order approximation to the Monod model also effectively described the experimental results, but the rate coefficients exhibited far less uncertainty, The more precise rate coefficients of the first-order model provided a better means than the Monod parameters, to quantitatively compare the reduction rates between metals, electron donors, and DMRB species. (C) 2002 Wiley Periodicals, Inc. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Liu, CX (reprint author), Pacific NW Natl Lab, POB 999,MSIN K8-96, Richland, WA 99352 USA. RI Liu, Chongxuan/C-5580-2009 NR 63 TC 179 Z9 186 U1 12 U2 99 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0006-3592 J9 BIOTECHNOL BIOENG JI Biotechnol. Bioeng. PD DEC 20 PY 2002 VL 80 IS 6 BP 637 EP 649 DI 10.1002/bit.10430 PG 13 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 614PA UT WOS:000179197500005 PM 12378605 ER PT J AU Baisden, WT Amundson, R Brenner, DL Cook, AC Kendall, C Harden, JW AF Baisden, WT Amundson, R Brenner, DL Cook, AC Kendall, C Harden, JW TI A multiisotope C and N modeling analysis of soil organic matter turnover and transport as a function of soil depth in a California annual grassland soil chronosequence SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article DE terrestrial ecosystem biogeochemistry model; soil organic matter dynamics; radiocarbon; carbon; nitrogen; soil chronosequence ID CHEMICAL-WEATHERING RATES; N-15 NATURAL-ABUNDANCE; BIOGEOCHEMICAL THEORY; TEMPERATE FORESTS; CARBON; NITROGEN; PHOSPHORUS; NUTRIENT; CLIMATE; FLUXES AB We examine soil organic matter (SOM) turnover and transport using C and N isotopes in soil profiles sampled circa 1949, 1978, and 1998 (a period spanning pulse thermonuclear (14)C enrichment of the atmosphere) along a 3-million-year annual grassland soil chronosequence. Temporal differences in soil Delta(14)C profiles indicate that inputs of recently living organic matter (OM) occur primarily in the upper 20-30 cm but suggest that OM inputs can occur below the primary rooting zone. A three-pool SOM model with downward transport captures most observed variation in Delta(14)C, percentages of C and N, delta(13)C, and delta(15)N, supporting the commonly accepted concept of three distinct SOM pools. The model suggests that the importance of the decadal SOM pool in N dynamics is greatest in young and old soils. Altered hydrology and possibly low pH and/or P dynamics in highly developed old soils cause changes in soil C and N turnover and transport of importance for soil biogeochemistry models. C1 Univ Calif Berkeley, Dept ESPM, Ecosyst Sci Div, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. US Geol Survey, Menlo Pk, CA 94025 USA. RP Baisden, WT (reprint author), Massey Univ, Private Bag 11052, Palmerston North, New Zealand. EM BaisdenT@landcare.cri.nz RI Baisden, Troy/B-9831-2008; Amundson, Ronald /E-2654-2015 OI Baisden, Troy/0000-0003-1814-1306; NR 82 TC 68 Z9 69 U1 4 U2 54 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD DEC 20 PY 2002 VL 16 IS 4 AR 1135 DI 10.1029/2001GB001823 PG 26 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 649LC UT WOS:000181209000001 ER PT J AU Chan, RS Sakash, JB Macol, CP West, JA Tsuruta, H Kantrowitz, ER AF Chan, RS Sakash, JB Macol, CP West, JA Tsuruta, H Kantrowitz, ER TI The role of intersubunit interactions for the stabilization of the T state of Escherichia coli aspartate transcarbamoylase SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID CONCERTED ALLOSTERIC TRANSITION; CATALYTIC CHAIN; DOMAIN CLOSURE; HETEROTROPIC INTERACTIONS; REGULATORY CHAIN; HOMOTROPIC COOPERATIVITY; RESIDUES 230-245; R-STATE; BINDING; CARBAMOYLTRANSFERASE AB Homotropic cooperativity in Escherichia coli aspartate transcarbamoylase results from the substrate-induced transition from the T to the R state. These two alternate states are stabilized by a series of interdomain and intersubunit interactions. The salt link between Lys-143 of the regulatory chain and Asp-236 of the catalytic chain is only observed in the T state. When Asp-236 is replaced by alanine the resulting enzyme exhibits full activity, enhanced affinity for aspartate, no cooperativity, and no heterotropic interactions. These characteristics are consistent with an enzyme locked in the functional R state. Using small angle x-ray scattering, the structural consequences of the D236A mutant were characterized. The unliganded D236A holoenzyme appears to be in a new structural state that is neither T, R, nor a mixture of T and R states. The structure of the native D236A holoenzyme is similar to that previously reported for another mutant holoenzyme (E239Q) that also lacks intersubunit interactions. A hybrid version of aspartate transcarbamoylase in which one catalytic subunit was wild-type and the other had the D236A mutation was also investigated. The hybrid holoenzyme, with three of the six possible interactions involving Asp-236, exhibited homotropic cooperativity, and heterotropic interactions consistent with an enzyme with both T and R functional states. Small angle x-ray scattering analysis of the unligated hybrid indicated that the enzyme was in a new structural state more similar to the T than to the R state of the wild-type enzyme. These data suggest that three of the six intersubunit interactions involving D236A are sufficient to stabilize a T-like state of the enzyme and allow for an allosteric transition. C1 Boston Coll, Dept Chem, Merkert Chem Ctr, Chestnut Hill, MA 02467 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Kantrowitz, ER (reprint author), Boston Coll, Dept Chem, Merkert Chem Ctr, Chestnut Hill, MA 02467 USA. FU NCRR NIH HHS [P41 RR 01209]; NIGMS NIH HHS [GM 26237] NR 39 TC 10 Z9 10 U1 0 U2 0 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 DEC 20 PY 2002 VL 277 IS 51 BP 49755 EP 49760 DI 10.1074/jbc.M208919200 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 629AU UT WOS:000180028900087 PM 12399459 ER PT J AU Csaszar, AG Szalay, PG Leininger, ML AF Csaszar, AG Szalay, PG Leininger, ML TI The enthalpy of formation of (2)Pi CH SO MOLECULAR PHYSICS LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; ENERGY CORRECTIONS; HEATS; MODEL; APPROXIMATION; EXCITATION; HYDROXYL; SPECTRA; PURSUIT AB The standard enthalpy of formation, Delta(f)H(o), of (2)Pi CH has been determined at converged levels of ab initio electronic structure theory, including high order coupled cluster and full configuration interaction benchmarks. The atomic Gaussian basis sets employed include the (aug)cc-p(C)VXZ family with X = 3,4,5 and 6. Extrapolations to the complete one-particle basis set and the full configuration interaction limits, where appropriate, have been performed to reduce remaining computational errors. Additional improvements in the enthalpy of formation of (2)Pi, CH were achieved by appending the valence-only treatment with core-valence correlation, relativistic effects including spin-orbit correlation, and the diagonal Born-Oppenheimer correction. The recommended values for Delta(f)H(0)(o) and Delta(f)H(298)(o) Of (2)Pi CH are 592.48(-0.56)(+0.47) kJ mol(-1) and 595.93(-0.56)(+0.47) kJ mol(-1), respectively. C1 Eotvos Lorand Univ, Dept Theoret Chem, H-1518 Budapest 112, Hungary. Sandia Natl Labs, Livermore, CA USA. RP Csaszar, AG (reprint author), Eotvos Lorand Univ, Dept Theoret Chem, POB 32, H-1518 Budapest 112, Hungary. EM csaszar@chem.elte.hu RI Csaszar, Attila/A-5241-2009; Szalay, Peter/C-8879-2015 OI Szalay, Peter/0000-0003-1885-3557 NR 41 TC 23 Z9 23 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0026-8976 EI 1362-3028 J9 MOL PHYS JI Mol. Phys. PD DEC 20 PY 2002 VL 100 IS 24 BP 3879 EP 3883 DI 10.1080/0026897021000016684 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 633RX UT WOS:000180297200013 ER PT J AU Rudenko, G Henry, L Henderson, K Ichtchenko, K Brown, MS Goldstein, JL Deisenhofer, J AF Rudenko, G Henry, L Henderson, K Ichtchenko, K Brown, MS Goldstein, JL Deisenhofer, J TI Structure of the LDL receptor extracellular domain at endosomal pH SO SCIENCE LA English DT Article ID LOW-DENSITY-LIPOPROTEIN; DEPENDENT LIGAND DISSOCIATION; CYSTEINE-RICH REPEAT; FAMILIAL HYPERCHOLESTEROLEMIA; APOLIPOPROTEIN-B; 3-DIMENSIONAL STRUCTURE; BACKBONE DYNAMICS; CALCIUM-BINDING; NMR STRUCTURE; MODULES AB The low-density lipoprotein receptor mediates cholesterol homeostasis through endocytosis of lipoproteins. It discharges its ligand in the endosome at pH<6. In the crystal structure at pH=5.3, the ligand-binding domain (modules R2 to R7) folds back as an arc over the epidermal growth factor precursor homology domain (the modules A, B, beta propeller, and C). The modules R4 and R5, which are critical for lipoprotein binding, associate with the beta propeller via their calcium-binding loop. We propose a mechanism for lipoprotein release in the endosome whereby the beta propeller functions as an alternate substrate for the ligand-binding domain, binding in a calcium-dependent way and promoting lipoprotein release. C1 Univ Texas, SW Med Ctr, Dept Biochem, Dallas, TX 75390 USA. Univ Texas, SW Med Ctr, Dept Mol Genet, Dallas, TX 75390 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley Ctr Struct Biol, Berkeley, CA 94720 USA. RP Deisenhofer, J (reprint author), Univ Texas, SW Med Ctr, Dept Biochem, 5323 Harry Hines Blvd Y4-206, Dallas, TX 75390 USA. EM Johann.Deisenhofer@UTSouthwestern.edu OI Ichtchenko, Konstantin/0000-0002-2198-1325 FU NHLBI NIH HHS [HL20948] NR 48 TC 278 Z9 283 U1 2 U2 16 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 DEC 20 PY 2002 VL 298 IS 5602 BP 2353 EP 2358 DI 10.1126/science.1078124 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 627DG UT WOS:000179915900046 PM 12459547 ER PT J AU Liu, XY Daw, MS Kress, JD Hanson, DE Arunachalam, V Coronell, DG Liu, CL Voter, AF AF Liu, XY Daw, MS Kress, JD Hanson, DE Arunachalam, V Coronell, DG Liu, CL Voter, AF TI Ion solid surface interactions in ionized copper physical vapor deposition SO THIN SOLID FILMS LA English DT Article DE copper; molecular dynamics ID MOLECULAR-DYNAMICS SIMULATIONS; FILM GROWTH; CU; BOMBARDMENT; ATOMS; CU(111); YIELDS; AR AB A thorough understanding of ion-solid surface interactions is important for the predictive modeling of ionized metal plasma (IMP) Cu physical vapor deposition (PVD) at feature scales. Besides sticking coefficients and sputter yields, characterizations such as angular distributions of sputtered and reflected particles, and thermal-accommodation coefficients are also needed as inputs for a feature scale process simulator. Molecular dynamic (MD) simulations have been used to provide pertinent information and physical insights. MD results for Ar+/Cu and Cu+/Cu systems as a function of hyperthermal ion energies and incidence angles are reported. The issue of integrating different sticking coefficients for different surface roughness is addressed, based on ion travel distance analysis. We have found that the angular distribution of sputtered particles is not cosine, but can be described by a simple Gaussian-like formula. Ion reflection characteristics are also analyzed. (C) 2002 Elsevier Science B.V. All tights reserved. C1 Motorola Inc, Phys Sci Res Labs, Computational Nanosci Grp, Los Alamos, NM 87545 USA. Motorola Inc, Digital DNA Labs, Austin, TX 78721 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Liu, XY (reprint author), Motorola Inc, Phys Sci Res Labs, Computational Nanosci Grp, Los Alamos, NM 87545 USA. NR 32 TC 14 Z9 14 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 20 PY 2002 VL 422 IS 1-2 BP 141 EP 149 AR PII S0040-6090(02)00870-2 DI 10.1016/S0040-6090(02)00870-2 PG 9 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 626ZN UT WOS:000179903800024 ER PT J AU Jeong, BS Budai, JD Norton, DP AF Jeong, BS Budai, JD Norton, DP TI Epitaxial stabilization of single crystal anatase films via reactive sputter deposition SO THIN SOLID FILMS LA English DT Article DE epitaxy; oxides; sputtering; titanium oxide ID THIN-FILMS; OPTICAL-PROPERTIES; TITANIUM-DIOXIDE; TIO2 FILMS; GROWTH; TEMPERATURE; RUTILE AB Single crystal-like TiO2 films possessing the anatase crystal structure have been realized on (001) LaAlO3 using reactive sputter deposition. The anatase polymorph could be epitaxially stabilized over a wide range of deposition temperatures and oxygen pressures. Both in-plane and out-of-plane X-ray diffraction measurements reflect a high degree of crystallinity for the deposited films. Thickness oscillations in the X-ray diffraction intensity and atomic force microscopy measurements indicate that the films are remarkably smooth, with surface morphology that is limited by that of the substrate. This result illustrates the effectiveness for epitaxy in stabilizing metastable phases, in particular for anatase, through matching of lattice spacing and nucleation chemistry. (C) 2002 Elsevier Science B.V. All rights reserved. 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, 100 Rhines Hall,POB 116400, Gainesville, FL 32611 USA. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 24 TC 30 Z9 30 U1 0 U2 17 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 20 PY 2002 VL 422 IS 1-2 BP 166 EP 169 AR PII S0040-6090(02)00719-8 DI 10.1016/S0040-6090(02)00719-8 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 626ZN UT WOS:000179903800028 ER PT J AU Kalish, ML Korber, BT Pillai, S Robbins, KE Leo, YS Saekhou, A Verghese, I Gerrish, P Goh, CL Lupo, D Tan, BH Brown, TM Chan, R AF Kalish, ML Korber, BT Pillai, S Robbins, KE Leo, YS Saekhou, A Verghese, I Gerrish, P Goh, CL Lupo, D Tan, BH Brown, TM Chan, R TI The sequential introduction of HIV-1 subtype B and CRF01_AE in Singapore by sexual transmission: Accelerated V3 region evolution in a subpopulation of Asian CRF01 viruses SO VIROLOGY LA English DT Article DE HIV-1; Singapore; CRF01_AE; V3 loop; envelope sequences; diversity; glycosylation sites; risk group; evolution; Asia ID HUMAN-IMMUNODEFICIENCY-VIRUS; N-LINKED GLYCOSYLATION; INJECTING DRUG-USERS; DEFICIENCY SYNDROME AIDS; AMINO-ACID SUBSTITUTION; LANGERHANS CELL TROPISM; ENVELOPE GLYCOPROTEIN; PHYLOGENETIC ANALYSIS; NORTHERN THAILAND; GENETIC DIVERSITY AB The rapid spread of the human immunodeficiency virus type 1 (HIV-1) circulating recombinant form (CRF) 01_AE throughout Asia demonstrates the dynamic nature of emerging epidemics. To further characterize the dissemination of these strains regionally, we sequenced 58 strains from Singapore and found that subtype B and CRF01 were introduced separately, by homosexual and heterosexual transmission, respectively. Protein similarity scores of the Singapore CRF01, as well as all Asian strains, demonstrated a complex distribution of scores in the V3 loop-some strains had very similar V3 loop sequences, while others were highly divergent. Furthermore, we found a strong correlation between the loss of a V3 glycosylation site and the divergent strains. This suggests that loss of this glycosylation site may make the V3 loop more susceptible to immune surveillance. The identification of a rapidly evolving population of CRF01_AE variants should be considered when designing new candidate vaccines and when evaluating breakthrough strains from current vaccine trials. (C) 2002 Elsevier Science (USA). C1 Ctr Dis Control & Prevent, Atlanta, GA 30333 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Communicable Dis Ctr, Singapore 308205, Singapore. Natl Skin Ctr, Singapore 1130, Singapore. RP Kalish, ML (reprint author), Ctr Dis Control & Prevent, 1600 Clifton Rd,Mailstop G19, Atlanta, GA 30333 USA. OI Gerrish, Philip/0000-0001-6393-0553; Korber, Bette/0000-0002-2026-5757 NR 84 TC 13 Z9 13 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0042-6822 J9 VIROLOGY JI Virology PD DEC 20 PY 2002 VL 304 IS 2 BP 311 EP 329 DI 10.1006/viro.2002.1691 PG 19 WC Virology SC Virology GA 629QM UT WOS:000180060400017 PM 12504572 ER PT J AU Alumbaugh, D Chang, PY Paprocki, L Brainard, JR Glass, RJ Rautman, CA AF Alumbaugh, D Chang, PY Paprocki, L Brainard, JR Glass, RJ Rautman, CA TI Estimating moisture contents in the vadose zone using cross-borehole ground penetrating radar: A study of accuracy and repeatability SO WATER RESOURCES RESEARCH LA English DT Article DE GPR; vadose zone; moisture content ID TIME-DOMAIN REFLECTOMETRY; SOIL-WATER CONTENT; LABORATORY CALIBRATION; SATURATION AB [1] Experiments have been conducted to demonstrate the accuracy and precision of moisture content estimates derived from cross-borehole ground penetrating radar (XBGPR) measurements made within the vadose zone. Both numerical simulations and field data demonstrate that although a certain amount of image smearing occurs under ideal conditions the general trends in the spatial variation of the moisture content can be estimated by a simple empirical transformation from images of electromagnetic (EM) wave velocity. The field results are verified by comparing the radar-derived images of volumetric moisture content to neutron log derived values. When an appropriate site-specific conversion from radar wave velocity to moisture content is applied, a root mean square (RMS) error of 2.0-3.1% volumetric moisture content exists between the two sets. Further comparison of the two different data sets along with analysis of plots of the ray density through each cell indicates that regions of high moisture content are better resolved than regions of low moisture and that most of the discrepancy between radar-derived and neutron-derived moisture contents occurs in regions of high moisture content. Better spatial resolution can be provided if dense station spacing is used. However, the amount of extra time required to acquire the extra data may limit the usefulness of the method. Repeatability measurements made with five data sets demonstrate that the precision error of the data acquisition system employed averages about 0.54 ns, which translates to about a 0.5% error in moisture content estimation. C1 New Mexico Inst Min & Technol, Socorro, NM 87801 USA. Univ Wisconsin, Geol Engn Program, Madison, WI 53706 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Alumbaugh, D (reprint author), Univ Wisconsin, Geol Engn Program, 2258 Engn Hall,1415 Engn Dr, Madison, WI 53706 USA. NR 29 TC 63 Z9 66 U1 2 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 20 PY 2002 VL 38 IS 12 AR 1309 DI 10.1029/2001WR000754 PG 12 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 650DB UT WOS:000181246200001 ER PT J AU Holt, RM Wilson, JL Glass, RJ AF Holt, RM Wilson, JL Glass, RJ TI Spatial bias in field-estimated unsaturated hydraulic properties SO WATER RESOURCES RESEARCH LA English DT Article DE unsaturated zone; geostatistics; spatial bias; measurement error; inversion model error; hydraulic property measurement ID STOCHASTIC-ANALYSIS; TENSION INFILTROMETERS; HETEROGENEOUS SOILS; DISC INFILTROMETERS; STRATIFIED SOILS; FLOW; CONDUCTIVITY; VARIABILITY; MEDIA; INFILTRATION AB [1] We use a Monte Carlo approach to explore the potential impact of observation and inversion model errors on the spatial statistics of field-estimated unsaturated hydraulic properties. For this analysis we simulate tension infiltrometer measurements in a series of idealized realities, each consisting of spatially correlated random property fields. We consider only simple measurement errors that can be easily modeled. We show that estimated hydraulic properties are strongly biased by small, simple observation and inversion model errors. This bias can lead to order-of-magnitude errors in spatial statistics and artificial cross correlation between measured properties. The magnitude of bias varies with the true mean of the property field, the type of error considered, and the type of spatial statistic. We find no unique indicators of bias as property values may appear reasonable and spatial statistics may look realistic. Our results suggest new concerns for geostatisticians, stochastic modelers, and unsaturated zone practitioners who are unaware of the potential impact of spatial bias in field-estimated properties. C1 Univ Mississippi, Dept Geol & Geol Engn, University, MS 38677 USA. Sandia Natl Labs, Flow Visualizat & Proc Lab, Albuquerque, NM 87185 USA. New Mexico Inst Min & Technol, Dept Earth & Environm Sci, Socorro, NM 87801 USA. RP Holt, RM (reprint author), Univ Mississippi, Dept Geol & Geol Engn, University, MS 38677 USA. NR 35 TC 2 Z9 2 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 20 PY 2002 VL 38 IS 12 AR 1311 DI 10.1029/2002WR001336 PG 11 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 650DB UT WOS:000181246200004 ER PT J AU Moridis, GJ AF Moridis, GJ TI Semianalytical solutions of radioactive or reactive solute transport in variably fractured layered media SO WATER RESOURCES RESEARCH LA English DT Article DE radioactive tracers; solute transport; layered fractured rocks; matrix-fracture systems; semianalytical solutions ID CONTAMINANT TRANSPORT; POROUS-MEDIA; BOUNDARY-CONDITIONS; SINGLE FRACTURE; DIFFUSION; MODEL; ROCKS AB [1] In this paper, semianalytical solutions are developed for the problem of transport of radioactive or reactive solute tracers through a layered system of heterogeneous fractured media with misaligned fractures. The tracer transport equations in the nonflowing matrix account for (1) diffusion, (2) surface diffusion, (3) mass transfer between mobile and immobile water fractions, (4) linear kinetic or equilibrium physical, chemical, or combined sorption or colloid filtration, and (5) radioactive decay or first-order chemical reactions. The tracer transport equations in the fractures account for the same processes, in addition to advection and hydrodynamic dispersion. Any number of radioactive decay daughter products (or products of a linear, first-order reaction chain) can be tracked. The solutions, which are analytical in the Laplace space, are numerically inverted to provide the solution in time and can accommodate any number of fractured and/or porous layers. The solutions are verified using analytical and numerical solutions for limiting cases of solute and colloid transport through fractured and porous media. The effect of important parameters on the transport of H-3, Tc-99, Np-237, and Pu-239 (and its daughters) is investigated in several test problems involving layered geological systems of varying complexity. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Moridis, GJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd,MS 90-1116, Berkeley, CA 94720 USA. NR 30 TC 7 Z9 7 U1 1 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 20 PY 2002 VL 38 IS 12 AR 1310 DI 10.1029/2001WR001028 PG 24 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 650DB UT WOS:000181246200003 ER PT J AU Walvoord, MA Plummer, MA Phillips, FM Wolfsberg, AV AF Walvoord, MA Plummer, MA Phillips, FM Wolfsberg, AV TI Deep arid system hydrodynamics - 1. Equilibrium states and response times in thick desert vadose zones SO WATER RESOURCES RESEARCH LA English DT Article DE modeling; vapor flow; chloride; matric potential ID CHLORIDE-MASS-BALANCE; SOIL-WATER MOVEMENT; UNSATURATED ZONE; ENVIRONMENTAL TRACERS; NATURAL RECHARGE; GREAT-BASIN; FLOW; FLUX; PALEORECHARGE; DIFFUSION AB [1] Quantifying moisture fluxes through deep desert soils remains difficult because of the small magnitude of the fluxes and the lack of a comprehensive model to describe flow and transport through such dry material. A particular challenge for such a model is reproducing both observed matric potential and chloride profiles. We propose a conceptual model for flow in desert vadose zones that includes isothermal and nonisothermal vapor transport and the role of desert vegetation in supporting a net upward moisture flux below the root zone. Numerical simulations incorporating this conceptual model match typical matric potential and chloride profiles. The modeling approach thereby reconciles the paradox between the recognized importance of plants, upward driving forces, and vapor flow processes in desert vadose zones and the inadequacy of the downward-only liquid flow assumption of the conventional chloride mass balance approach. Our work shows that water transport in thick desert vadose zones at steady state is usually dominated by upward vapor flow and that long response times, of the order of 10(4)-10(5) years, are required to equilibrate to existing arid surface conditions. Simulation results indicate that most thick desert vadose zones have been locked in slow drying transients that began in response to a climate shift and establishment of desert vegetation many thousands of years ago. C1 Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. New Mexico Inst Min & Technol, Earth & Environm Sci Dept, Socorro, NM 87801 USA. RP Walvoord, MA (reprint author), US Geol Survey, Denver Fed Ctr, Box 25046,MS 413, Lakewood, CO 80225 USA. NR 58 TC 52 Z9 54 U1 1 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 20 PY 2002 VL 38 IS 12 AR 1308 DI 10.1029/2001WR000824 PG 15 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 650DB UT WOS:000181246200002 ER PT J AU Light, TEL Jacobson, AR AF Light, TEL Jacobson, AR TI Characteristics of impulsive VHF lightning signals observed by the FORTE satellite SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE lightning; narrow bipolar events; optical emissions; VHF emissions; satellite observations ID TRANSIONOSPHERIC PULSE PAIRS; OPTICAL-EMISSIONS; PHENOMENOLOGY; RADIATION; FREQUENCY; CLOUDS AB [1] We study very high frequency (VHF) and optical emissions from lightning, observed by the FORTE satellite, differentiating between impulsive (transionospheric pulse pairs (TIPPs)) and nonimpulsive events. TIPPs are seen to constitute 47% of the FORTE VHF data but only 32% of the optically coincident data. The median peak optical irradiance of the optical emission associated with TIPPs is 916 muW/m(2) at FORTE and for non-TIPPs is 195 muW/m(2). The median effective pulse width of the optical signal from TIPPs is 658 mus, and it is 548 mus for non-TIPPs. In the VHF, both event types have similar observed peak powers (0.086 mV(2)/m(2) and 0.089 mV(2)/m(2), for TIPPs and non-TIPPs, respectively). The optically coincident lightning (of either type) is weaker in peak VHF emission than is the lightning that lacks coincident optical signals, although for non-TIPPs, the stronger the VHF peak, the more likely the event is to have a coincident optical signal. For TIPPs, however, this is true only for events with peak E-2 < 0.1 mV(2)/m(2). Above that threshold, TIPPs are increasingly less likely to show coincident optical emission with increasing VHF peak E-2. For both TIPPs and non-TIPPs, the peak current reported by the U. S. National Lightning Detection Network(TM) and peak VHF power reported by FORTE are statistically proportional. The nature of the proportionality appears to depend upon the polarity of the discharge but not upon the event type. We also find that only 11% of TIPPs are associated with negative-polarity discharges, compared to 75% of non-TIPPs. Finally, we find that TIPPs arise from events with altitudes of 6-15 km, although we see optical coincidence only for those TIPPs occurring above similar to 10 km. C1 Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. RP Light, TEL (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci Grp, NIS-1,Mail Stop D46, Los Alamos, NM 87545 USA. EM tlavezzi@lanl.gov; ajacobson@lanl.gov NR 24 TC 33 Z9 36 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 19 PY 2002 VL 107 IS D24 AR 4756 DI 10.1029/2001JD001585 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 650FZ UT WOS:000181253700013 ER PT J AU Hache, JJ Laskin, J Futrell, JH AF Hache, JJ Laskin, J Futrell, JH TI Relative proton affinities from kinetic energy release distributions for dissociation of proton-bound dimers SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ION-CYCLOTRON RESONANCE; GAS-PHASE BASICITIES; THERMAL KINETICS; ALCOHOLS; DEPENDENCE; ENTROPIES; MOLECULE; METHANOL; AMINES AB Kinetic energy release distributions (KERDs) upon dissociation of proton-bound dimers are utilized along with finite heat bath theory analysis to obtain relative proton affinities of monomeric species composing the dimer. The proposed approach allows accurate measurement of relative proton affinities based on KERD measurements for the compound with unknown thermochemical properties vs a single reference base. It also allows distinguishing the cases when dissociation of proton-bound dimers is associated with a reverse activation barrier, for which both our approach and the kinetic method become inapplicable. Results are reported for the n-butanol-n-propanol dimer, for which there is no significant difference in entropy effects for two reactions, and for the pyrrolidine-1,2-ethylenediamine dimer, which is characterized by a significant difference in entropy effects for the two competing reactions. Relative protonation affinities of -1.0 +/- 0.3 kcal/mol for the n-butanol-n-propanol pair and 0.27 +/- 0.10 kcal/mol for the pyrrolidine-1,2-ethylenediamine pair are in good agreement with literature values. Relative reaction entropies were extracted from the branching ratio and KERD measurements. Good correspondence was found between the relative reaction entropies for the n-butanol-n-propanol dimer (Delta(DeltaS(double dagger)) = -0.3 +/- 1.5 cal/mol K) and the relative protonation entropy for the two monomers (Delta(DeltaS(p)) = 0). However, the relative reaction entropy for the pyrrolidine-1,2-ethylenediamine dimer is higher than the difference in protonation entropies (Delta(DeltaS(double dagger)) = 8.2 +/- 0.5 cal/mol K vs Delta(DeltaS(p)) = 5 cal/mol K). C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Laskin, J (reprint author), Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, POB 999 K8-96, Richland, WA 99352 USA. RI Laskin, Julia/H-9974-2012 OI Laskin, Julia/0000-0002-4533-9644 NR 34 TC 11 Z9 11 U1 0 U2 2 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 DEC 19 PY 2002 VL 106 IS 50 BP 12051 EP 12057 DI 10.1021/jp026515p PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 627EV UT WOS:000179921000009 ER PT J AU Liu, SH Miller, AD Gaffney, KJ Szymanski, P Garrett-Roe, S Bezel, I Harris, CB AF Liu, SH Miller, AD Gaffney, KJ Szymanski, P Garrett-Roe, S Bezel, I Harris, CB TI Direct observation of two-dimensional electron solvation at alcohol/Ag(111) interfaces SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID FEMTOSECOND DYNAMICS; 2-PHOTON PHOTOEMISSION; HYDRATED ELECTRON; SOLVENT DYNAMICS; METAL-SURFACES; IMAGE STATES; SPECTROSCOPY; RELAXATION; LOCALIZATION; ADSORPTION AB Time-resolved two-photon photoemission was used to investigate the two-dimensional electron solvation by methanol, 1-propanol, 1-butanol, and 1-pentanol overlayers on a Ag(111) surface. For each system at coverages higher than one monolayer, several image potential state series with time-dependent energies were observed by using two-photon photoemission indicating that multiple time-dependent local work functions can originate from multiple coverages. The time-dependent energy relaxation seen is attributed to the rotation of the adsorbate molecular dipoles to solvate the electron. This rotation lowers the electron-layer interaction energy,causing a dynamic reduction of the local work function which is a signature of the solvation of the electron by the adsorbate layer. A classical electron-disk dipole model supports the conclusion that the dynamic variation in the image potential state energies results from a local work function effect and indicates that the evolution of the energy results from the time-dependent projection of the molecular dipole onto the surface normal on the femtosecond time scale. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Harris, CB (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Garrett-Roe, Sean/C-6037-2011 OI Garrett-Roe, Sean/0000-0001-6199-8773 NR 44 TC 27 Z9 27 U1 1 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 DEC 19 PY 2002 VL 106 IS 50 BP 12908 EP 12915 DI 10.1021/jp025772r PG 8 WC Chemistry, Physical SC Chemistry GA 627EW UT WOS:000179921100010 ER PT J AU Vener, MV Leontyev, IV Dyakov, YA Basilevsky, MV Newton, MA AF Vener, MV Leontyev, IV Dyakov, YA Basilevsky, MV Newton, MA TI Application of the linearized MD approach for computing equilibrium solvation free energies of charged and dipolar solutes in polar solvents SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; IONIC HYDRATION; THERMODYNAMIC INTEGRATION; ELECTROSTATIC POTENTIALS; BROMIDE ION; MONTE-CARLO; AB-INITIO; WATER; MODEL; TRUNCATION AB The linearized MD technique is developed in order to. treat systematically free energies of simple charged and dipolar solutes in water. The solvent electrostatic response field in the solute region is modeled by averaging instantaneous fields found in a MD computation for solvent configurations confined within a cavity that conforms to the real shape of the solute particle. At this stage, all electrostatic interactions are explicitly treated inside the cavity. The solvent in the external region (outside the cavity) is modeled in terms of a standard continuum theory. For nonspherical cavities, the present approach is more accurate than the field computation employed at the preceding MD stage, where spherically truncated Coulomb potentials are modified by the reaction field corrections. We considered two different linearization schemes based on a computation of either the average response field or of its fluctuations. Only the first algorithm proved to be successful. For a series of single-charged monatomic cations and anions, it provides free energies that deviate by few percent from those found in full MD computations. The results are stable relative to a separation of the whole space occupied by the solvent into explicit solvent region (inside the cavity) and the continuum region (outside the cavity). The two-site dipolar dumbbell system was also studied in the range of intersite separation D within 2 Angstrom < D < 10 Angstrom. At the stage of the field computation, three different types of its solvation shell were considered: spherical and bispherical cavities and periodic solvent environment monitored in terms of Ewald method. Free solvation energies are the same (within 1 kcal/mol) for all three models. A smooth dependence of the mean field potential is observed as a function of separation D but its asymptotic value differs by 4 kcal/mol from the free energy computed for the isolated ion pair. The results generally agree with those obtained in the literature in terms of full MD simulations. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Karpov Inst Phys Chem, Moscow 105064, Russia. RP Basilevsky, MV (reprint author), Brookhaven Natl Lab, Dept Chem, POB 5000, Upton, NY 11973 USA. RI Leontyev, Igor/B-6981-2013; Dyakov, Yuri/M-4619-2013 NR 60 TC 30 Z9 31 U1 0 U2 5 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 DEC 19 PY 2002 VL 106 IS 50 BP 13078 EP 13088 DI 10.1021/jp021396z PG 11 WC Chemistry, Physical SC Chemistry GA 627EW UT WOS:000179921100030 ER PT J AU Cullum, J Zhang, T AF Cullum, J Zhang, T TI Two-sided Arnoldi and nonsymmetric Lanczos algorithms SO SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS LA English DT Article DE two-sided Arnoldi; nonsymmetric Lanczos; equivalences; relationships; iterative methods; reduced-order systems; eigenvalues; model reduction ID EIGENVALUE PROBLEMS; MATRICES AB We introduce new two-sided Arnoldi recursions and use them to de ne a model reduction procedure for large, linear, time-invariant, multi-input/multi-output differential algebraic systems. We prove that this procedure has desirable moment matching properties. We de ne a corresponding model reduction procedure which is based on a band nonsymmetric Lanczos recursion and prove that if the deflation is exact and there are no breakdowns in the recursions, then these two model reduction procedures generate identical reduced-order systems. We prove similar equivalences for corresponding eigenelement procedures. We concentrate on the theoretical properties of the new algorithms. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. IBM Corp, Thomas J Watson Res Ctr, Yorktown Hts, NY 10598 USA. RP Cullum, J (reprint author), Los Alamos Natl Lab, MS B250, Los Alamos, NM 87545 USA. NR 19 TC 19 Z9 19 U1 0 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0895-4798 J9 SIAM J MATRIX ANAL A JI SIAM J. Matrix Anal. Appl. PD DEC 19 PY 2002 VL 24 IS 2 BP 303 EP 319 AR PII S0895479898339013 DI 10.1137/S0895479898339013 PG 17 WC Mathematics, Applied SC Mathematics GA 639QL UT WOS:000180640700001 ER PT J AU Amestoy, PR Puglisi, C AF Amestoy, PR Puglisi, C TI An unsymmetrized multifrontal LU factorization SO SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS LA English DT Article DE sparse linear equations; unsymmetric matrices; Gaussian elimination; multifrontal methods; elimination tree ID LINEAR-EQUATIONS; SPARSE-MATRIX; ELIMINATION AB A well-known approach to computing the LU factorization of a general unsymmetric matrix A is to build the elimination tree associated with the pattern of the symmetric matrix A + A(T) and use it as a computational graph to drive the numerical factorization. This approach, although very efficient on a large range of unsymmetric matrices, does not capture the unsymmetric structure of the matrices. We introduce a new algorithm which detects and exploits the structural asymmetry of the submatrices involved during the processing of the elimination tree. We show that with the new algorithm, significant gains, both in memory and in time, to perform the factorization can be obtained. C1 ENSEEIHT, IRIT, F-31071 Toulouse, France. Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RP Amestoy, PR (reprint author), ENSEEIHT, IRIT, 2 Rue Camichel, F-31071 Toulouse, France. NR 27 TC 37 Z9 37 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0895-4798 J9 SIAM J MATRIX ANAL A JI SIAM J. Matrix Anal. Appl. PD DEC 19 PY 2002 VL 24 IS 2 BP 553 EP 569 AR PII S0895479800375370 DI 10.1137/S0895479800375370 PG 17 WC Mathematics, Applied SC Mathematics GA 639QL UT WOS:000180640700016 ER PT J AU Kajii, Y Kato, S Streets, DG Tsai, NY Shvidenko, A Nilsson, S McCallum, I Minko, NP Abushenko, N Altyntsev, D Khodzer, TV AF Kajii, Y Kato, S Streets, DG Tsai, NY Shvidenko, A Nilsson, S McCallum, I Minko, NP Abushenko, N Altyntsev, D Khodzer, TV TI Boreal forest fires in Siberia in 1998: Estimation of area burned and emissions of pollutants by advanced very high resolution radiometer satellite data SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE Siberian forest fires; estimation by AVHRR ID CARBON-MONOXIDE; RUSSIAN FORESTS; IMPACT; OZONE; JAPAN; ASIA; TRANSPORT; ISLAND; FLUXES; CHINA AB The NOAA 12 advanced very high resolution radiometer detected extensive forest fires in boreal Siberia and northern Mongolia during April through October 1998, a year of extremely dry weather, in particular, in the Russian Far East. Analysis of the satellite data has been carried out to estimate the area burned and gaseous emissions to the atmosphere from the point of view of ozone precursors. The fires started in western and eastern Siberia and moved eastward during the summer, until they were concentrated in the Russian Far East, near Sakhalin Island, in the period of July to October. Satellite observations for the fire season and detailed characteristics of terrestrial vegetation in the form of multilayer geographic information systems were used along with published emission factors from similar fires to calculate the gaseous emissions. The total area burned is estimated to be 1.1x10(7) ha with 350 Tg of biomass consumed and 176 Tg of carbon released into the atmosphere. The carbon released into the atmosphere is calculated to contribute 516 Tg of CO2, 50 Tg of CO, 1.6 Tg of CH4, 1.1 Tg of NMHC, and 9.5 Tg of C particles as smoke. In addition, we estimate that 1.8 Tg of NOx (as NO2) were released. C1 Univ Tokyo, Adv Sci & Technol Res Ctr, Tokyo, Japan. Argonne Natl Lab, Decis & Informat Sci Div, Argonne, IL 60439 USA. Int Inst Appl Syst Anal, A-2361 Laxenburg, Austria. Russian Acad Sci, Siberian Div, Space Monitoring Ctr, Inst Solar Terr Phys, Irkutsk 664033, Russia. Russian Acad Sci, Limnol Inst, Siberian Branch, Irkutsk 666016, Russia. RP Kajii, Y (reprint author), Tokyo Metropolitan Univ, Dept Appl Chem, 1-1 Minami Osawa, Tokyo 1920397, Japan. EM kajii@atmchem.apchem.metro-u.ac.jp; shungo@atmchem.apchem.metro-u.ac.jp; dstreets@anl.gov; shvidenk@iiasa.ac.at; nickolai.minko@exicom.co.nz; alt@iszf.irk.ru RI Shvidenko, Anatoly/I-1505-2016 OI Shvidenko, Anatoly/0000-0001-7640-2151 NR 38 TC 52 Z9 55 U1 0 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 18 PY 2002 VL 107 IS D24 AR 4745 DI 10.1029/2001JD001078 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 650FV UT WOS:000181253200002 ER PT J AU Chevrel, SD Pinet, PC Daydou, Y Maurice, S Lawrence, DJ Feldman, WC Lucey, PG AF Chevrel, SD Pinet, PC Daydou, Y Maurice, S Lawrence, DJ Feldman, WC Lucey, PG TI Integration of the Clementine UV-VIS spectral reflectance data and the Lunar Prospector gamma-ray spectrometer data: A global-scale multielement analysis of the lunar surface using iron, titanium, and thorium abundances SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article DE Clementine; Lunar Prospector; mare basalts; lunar highlands; KREEP materials; South Pole-Aitken basin ID POLE-AITKEN BASIN; IMPACT-MELT BRECCIAS; COMPOSITIONAL UNITS; MOON; TIO2; FEO; VOLCANISM; NEUTRONS; ORIGIN; MANTLE AB We present a statistical analysis, based on a systematic clustering method, of a data set integrating the global abundances maps of iron, titanium, and thorium derived from Clementine and Lunar Prospector. Homogeneous geological units are compositionally characterized and spatially defined in relation to the major rock types sampled on the Moon. With the lowest abundances in Fe, Ti, and Th found on the Moon, the lunar highlands terrains are quite homogeneous with two major large feldspathic units, one being slightly more mafic than the other. Two distinct regions with unique compositions are unambiguously identified: the Procellarum KREEP Terrane (PKT) and the South Pole-Aitken (SPA). The PKT, which includes all the units with Th abundances higher than 3.5 ppm (KREEP-rich materials), is delimited by an almost continuous ring-like unit. In particular, it includes the western nearside maria, except for Mare Humorum. Within the PKTa Th-rich unit, corresponding to the highest Th concentrations found on the Moon, may represent KREEP volcanic deposits excavated from relatively shallow depth. With concentrations in Fe, Ti, and Th enhanced relative to the surrounding highlands, the South Pole-Aitken basin floor represents a large mafic anomaly on the farside, suggesting wide deposits of lower crust and possible mantle materials. However, due to indirect residual latitude effects in the Clementine spectral reflectance measurements, iron abundances might have been overestimated in SPA, thus implying that crustal materials, rather than mantle materials, might represent the dominant contributor to the mafic component exposed on the basin floor. C1 Observ Midi Pyrenees, Grp Rech Geodesie Spatiale, UMR5562, F-31400 Toulouse, France. Observ Midi Pyrenees, UMR5572, F-31400 Toulouse, France. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Hawaii, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. RP Chevrel, SD (reprint author), Observ Midi Pyrenees, Grp Rech Geodesie Spatiale, UMR5562, 14 Ave Edouard Belin, F-31400 Toulouse, France. EM Serge.Chevrel@cnes.fr RI Lawrence, David/E-7463-2015 OI Lawrence, David/0000-0002-7696-6667 NR 64 TC 13 Z9 13 U1 1 U2 4 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 DEC 18 PY 2002 VL 107 IS E12 AR 5132 DI 10.1029/2000JE001419 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 649PP UT WOS:000181217400001 ER PT J AU Saxon, E Luchansky, SJ Hang, HC Yu, C Lee, SC Bertozzi, CR AF Saxon, E Luchansky, SJ Hang, HC Yu, C Lee, SC Bertozzi, CR TI Investigating cellular metabolism of synthetic azidosugars with the Staudinger ligation SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ACETYLNEURAMINIC ACID BIOSYNTHESIS; BIFUNCTIONAL ENZYME CATALYZES; ACYL SIDE-CHAIN; FIRST 2 STEPS; SIALIC-ACID; 2-EPIMERASE/N-ACETYLMANNOSAMINE KINASE; RAT-LIVER; CELLS; GLYCOSYLATION; EXPRESSION AB The structure of sialic acid on living cells can be modulated by metabolism of unnatural biosynthetic precursors. Here we investigate the conversion of a panel of azide-functionalized mannosamine and glucosamine derivatives into cell-surface sialosides. A key tool in this study is the Staudinger ligation, a highly selective reaction between modified triarylphosphines and azides that produces an amide-linked product. A preliminary study of the mechanism of this reaction, and refined conditions for its in vivo execution, are reported. The reaction provided a means to label the glycoconjugate-bound azidosugars with biochemical probes. Finally, we demonstrate that the cell-surface Staudinger ligation is compatible with hydrazone formation from metabolically introduced ketones. These two strategies provide a means to selectively modify cell-surface glycans with exogenous probes. C1 Univ Calif Berkeley, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. RP Bertozzi, CR (reprint author), Univ Calif Berkeley, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. EM bertozzi@cchem.berkeley.edu FU NIGMS NIH HHS [GM 58867] NR 39 TC 167 Z9 168 U1 1 U2 44 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 DEC 18 PY 2002 VL 124 IS 50 BP 14893 EP 14902 DI 10.1021/ja027748x PG 10 WC Chemistry, Multidisciplinary SC Chemistry GA 625LB UT WOS:000179817000032 PM 12475330 ER PT J AU Wilds, CJ Pattanayek, R Pan, CL Wawrzak, Z Egli, M AF Wilds, CJ Pattanayek, R Pan, CL Wawrzak, Z Egli, M TI Selenium-assisted nucleic acid crystallography: Use of phosphoroselenoates for MAD phasing of a DNA structure SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID CRYSTAL-STRUCTURES; SELENOMETHIONYL PROTEINS; PHOSPHOROTHIOATE ANALOGS; ATOMIC-RESOLUTION; OLIGODEOXYRIBONUCLEOTIDES; OLIGONUCLEOTIDES; SEPARATION; HYDRATION AB The combination of synchrotron radiation and a variety of atoms or ions (either covalently attached to the biomolecule prior to crystallization or soaked into crystals) that serve as anomalous scatterers constitutes a powerful tool in the X-ray crystallographer's repertoire of structure determination techniques. Phosphoroselenoates in which one of the nonbridging phosphate oxygens in the backbone is replaced by selenium offer a simplified means for introducing an anomalous scatterer into oligonucleotides by conventional solid-phase synthesis. Unlike other methods that are used to derivatize DNA or RNA by covalent attachment of a heavy atom (i.e., bromine at the C5 position of pyrimidines), tedious synthesis of specialized nucleosides is not required. Introduction of selenium is readily accomplished in solid-phase oligonucleotide synthesis by replacing the standard oxidation agent with a solution of potassium selenocyanide. This results in a diastereomeric mixture of phosphoroselenoates that can be separated by strong anion-exchange HPLC. As a test case, all 10 DNA hexamers of the sequence CGCGCG containing a single phosphoroselenoate linkage (PSe) were prepared. Crystals were grown for a subset of them, and the structure of [d(C-PSe-GCGCG)](2) was determined by the multiwavelength anomalous dispersion technique and refined to 1.1 Angstrom resolution. C1 Vanderbilt Univ, Dept Biol Sci, Nashville, TN 37235 USA. Argonne Natl Lab, DND CAT Synchrotron Res Ctr, Adv Photon Source, Argonne, IL 60439 USA. RP Egli, M (reprint author), Vanderbilt Univ, Dept Biol Sci, 221 Kirkland Hall, Nashville, TN 37235 USA. RI Pan, Chongle/C-6960-2008; Wilds, Christopher/K-4012-2013 OI Wilds, Christopher/0000-0002-0336-4753 FU NIGMS NIH HHS [GM 55237] NR 36 TC 61 Z9 61 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 DEC 18 PY 2002 VL 124 IS 50 BP 14910 EP 14916 DI 10.1021/ja021058b PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 625LB UT WOS:000179817000034 PM 12475332 ER PT J AU Brennaman, MK Alstrum-Acevedo, JH Fleming, CN Jang, P Meyer, TJ Papanikolas, JM AF Brennaman, MK Alstrum-Acevedo, JH Fleming, CN Jang, P Meyer, TJ Papanikolas, JM TI Turning the [Ru(bpy)(2)dppz](2+) light-switch on and off with temperature SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID EXCITED-STATES; RUTHENIUM(II) COMPLEXES; POLYPYRIDYL COMPLEXES; CHARGE-TRANSFER; DNA; LIGAND; (2+); DEPENDENCE; RU(PHEN)(2)DPPZ(2+); PHOTOCHEMISTRY AB We report temperature-dependent excited-state lifetime measurements on [Ru(bpy)(2)dppz](2+) in both protic and aprotic solvents. These experiments yield a unifying picture of the excited-state photophysics that accounts for observations in both types of solvent. Our measurements support the notion of bpy-like and phz-like states associated with the dppz ligand and show that the ligand orbital associated with the bright state is similar in size to the corresponding orbital in the (MLCT)-M-3 state of [Ru(bpy)(3)](2+). In contrast to the current thinking, the experiments presented here indicate that the light-switch effect is not driven by a state reversal. Rather, they suggest that the dark state is always lowest in energy, even in aprotic solvents, and that the light-switch behavior is the result of a competition between energetic factors that favor the dark state and entropic factors that favor the bright (bpy) state. C1 Univ N Carolina, Dept Chem, Venable & Kenan Labs, Chapel Hill, NC 27599 USA. RP Meyer, TJ (reprint author), Los Alamos Natl Lab, MS A127, Los Alamos, NM 87545 USA. NR 31 TC 136 Z9 137 U1 1 U2 32 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 DEC 18 PY 2002 VL 124 IS 50 BP 15094 EP 15098 DI 10.1021/ja0279139 PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA 625LB UT WOS:000179817000057 PM 12475355 ER PT J AU Pagani, M Freeman, KH Ohkouchi, N Caldeira, K AF Pagani, M Freeman, KH Ohkouchi, N Caldeira, K TI Comparison of water column [CO2aq] with sedimentary alkenone-based estimates: A test of the alkenone- CO2 proxy SO PALEOCEANOGRAPHY LA English DT Article DE alkenones; delta C-13; carbon dioxide; Pacific Ocean ID CARBON-ISOTOPE FRACTIONATION; SEA-ICE FORMATION; EMILIANIA-HUXLEYI; GEPHYROCAPSA-OCEANICA; MASS-SPECTROMETRY; ATMOSPHERIC CO2; CENTRAL PACIFIC; TEMPERATURE; RATIO; DISTRIBUTIONS AB [1] The stable carbon isotopic compositions of alkenones have been used to interpret the long-term history of the partial pressure of atmospheric carbon dioxide ( pCO(2)). Although extensive water column and culture studies document the potential utility and limitations of this approach, to date the accuracy of pCO(2) values derived from sedimentary alkenones remains untested. For this study we establish Holocene-aged, alkenone-based CO2aq estimates ([CO2aq](alk)) from 20 sites along a central Pacific Ocean transect and compare them against both observed modern water column CO2aq and estimated preindustrial concentrations at the depth of alkenone production at each site. Although the [CO2aq](alk) track measured water column values, they are conspicuously lower than modern values across the subtropics. This offset likely reflects the contributions of anthropogenic CO2 in modern surface waters relative to preindustrial concentrations at the time of alkenone production. When a model-based estimate of anthropogenic CO2 is removed from the modern observed values, a majority (84%) of [CO2aq](alk) falls within 20% of modeled preindustrial values. Consistency between the modeled and alkenone-based estimates of preindustrial CO2 levels points to the relative accuracy of the alkenone-CO2 method across a wide range of ocean and biogeographic regimes, provided that phosphate concentrations, at the depth of haptophyte production, are reasonably constrained. It further suggests that light-limited growth and/or active carbon uptake, if they occur, have a negligible effect on reconstructed [CO2aq]. C1 Yale Univ, Dept Geol & Geophys, New Haven, CT 06520 USA. Penn State Univ, Dept Geosci, University Pk, PA 16872 USA. Woods Hole Oceanog Inst, Dept Marine Chem & Geochem, Woods Hole, MA 02543 USA. Lawrence Livermore Natl Lab, Climate & Carbon Cycle Grp, Livermore, CA 94550 USA. RP Pagani, M (reprint author), Yale Univ, Dept Geol & Geophys, POB 6666, New Haven, CT 06520 USA. EM mark.pagani@yale.edu; kate@essc.psu.edu; nohkouchi@whoi.edu; ekenc@LLNL.gov RI Caldeira, Ken/E-7914-2011; Freeman, Katherine/H-5140-2011; Pagani, Mark/B-3233-2008; Ohkouchi, Naohiko/B-2071-2008 OI Freeman, Katherine/0000-0002-3350-7671; NR 53 TC 18 Z9 18 U1 0 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0883-8305 EI 1944-9186 J9 PALEOCEANOGRAPHY JI Paleoceanography PD DEC 18 PY 2002 VL 17 IS 4 AR 1069 DI 10.1029/2002PA000756 PG 12 WC Geosciences, Multidisciplinary; Oceanography; Paleontology SC Geology; Oceanography; Paleontology GA 649ND UT WOS:000181214100001 ER PT J AU Park, WI Yi, GC Kim, MY Pennycook, SJ AF Park, WI Yi, GC Kim, MY Pennycook, SJ TI ZnO nanoneedles grown vertically on Si substrates by non-catalytic vapor-phase epitaxy SO ADVANCED MATERIALS LA English DT Article ID PHOTOLUMINESCENT PROPERTIES; THIN-FILMS; NANOWIRES; EMISSION C1 Pohang Univ Sci & Technol, Dept Mat Sci & Engn, Pohang 790784, Kyungbuk, South Korea. Samsung Adv Inst Sci & Technol, Suwon 440600, South Korea. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Yi, GC (reprint author), Pohang Univ Sci & Technol, Dept Mat Sci & Engn, Pohang 790784, Kyungbuk, South Korea. EM gcyi@postech.ac.kr RI Yi, Gyu-Chul/F-1326-2011; Park, Won Il/A-8362-2013; Kim, Miyoung/C-8316-2012 OI Park, Won Il/0000-0001-8312-4815; NR 17 TC 469 Z9 486 U1 6 U2 66 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 DEC 17 PY 2002 VL 14 IS 24 BP 1841 EP 1843 DI 10.1002/adma.200290015 PG 3 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 631QP UT WOS:000180178700014 ER PT J AU Agron, PG Sobecky, P Andersen, GL AF Agron, PG Sobecky, P Andersen, GL TI Establishment of uncharacterized plasmids in Escherichia coli by in vitro transposition SO FEMS MICROBIOLOGY LETTERS LA English DT Article DE in vitro transposition; pGT5; plasmid rescue; plasmid isolation; plasmid recovery; Pyrococcus abyssi ID GRAM-NEGATIVE BACTERIA; DNA-SEQUENCE; TN5; MUTAGENESIS; INSERTION; SYSTEM; GENE AB We present a simple approach that permits any circular plasmid, such as uncharacterized plasmids from diverse prokaryotes, to be established in Escherichia coli, thereby facilitating subsequent structural and functional studies. An in vitro transposition reaction is used to introduce a well-characterized replicon and selectable marker into purified plasmids, which are then used to transform E. coli. The approach was demonstrated using a small 3.4-kb archaeal plasmid and a large 60-kb uncharacterized plasmid from a Gram-negative bacterium. Replicon function in E coli was tested for each plasmid, and direct sequencing of the large plasmid revealed similarity to restriction-modification systems. (C) 2002 Published by Elsevier Science B.V. on behalf of the Federation of European Microbiological Societies. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Georgia Inst Technol, Sch Biol, Atlanta, GA 30332 USA. RP Andersen, GL (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, L-441,7000 E Ave, Livermore, CA 94550 USA. RI Andersen, Gary/G-2792-2015 OI Andersen, Gary/0000-0002-1618-9827 NR 16 TC 8 Z9 8 U1 0 U2 2 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 DEC 17 PY 2002 VL 217 IS 2 BP 249 EP 254 AR PII S0378-1097(02)01090-X DI 10.1111/j.1574-6968.2002.tb11483.x PG 6 WC Microbiology SC Microbiology GA 626QM UT WOS:000179884500018 PM 12480112 ER PT J AU Yim, H Kent, MS Matheson, A Stevens, MJ Ivkov, R Satija, S Majewski, J Smith, GS AF Yim, H Kent, MS Matheson, A Stevens, MJ Ivkov, R Satija, S Majewski, J Smith, GS TI Adsorption of sodium poly(styrenesulfonate) to the air surface of water by neutron and X-ray reflectivity and surface tension measurements: Polymer concentration dependence SO MACROMOLECULES LA English DT Article ID POLYELECTROLYTE CONCENTRATION-DEPENDENCE; BOVINE SERUM-ALBUMIN; HIGH IONIC-STRENGTH; LIGHT-SCATTERING; AQUEOUS-SOLUTIONS; MULTIMOLECULAR AGGREGATION; POLYSTYRENE SULFONATE; ELECTROLYTE SOLUTIONS; AIR/WATER INTERFACE; MONONUCLEOSOMAL DNA AB The adsorption of the strong polyelectrolyte sodium poly(styrenesulfonate) (NaPSS) to the air surface of water was investigated as a function of polymer concentration from the dilute regime to the beginning of the semidilute regime. Detailed segment profiles of the deuterated polymer were determined by neutron reflection (NR). Data were obtained for 0.67 and 2.50 M KCl. For two samples differing widely in molecular weight (1150 and 56.1 kg(mol), we find that with increasing polymer concentration the adsorbed amount first increases, reaches a maximum, and then decreases strongly. The PSS concentration at which the maximum is reached is dependent on both the molecular weight and the salt concentration in a manner that correlates with the chain overlap concentration. Regarding the segment profiles, at low polymer concentration the profiles are composed of a thin layer of high concentration at the air surface (trains), followed by a distinct second layer of much lower segment concentration that extends to larger depths into the liquid (loops and tails). Complementary X-ray reflection MR) revealed a localization of ions about 101 below the surface for dilute PSS concentration. This layer becomes more diffuse at higher PSS concentration, in conjunction with the decrease in PSS adsorbed amount measured by NR. This surprising behavior of the adsorbed amount with polymer concentration is not explained by current SCF theory treating the adsorption of strong polyelectrolytes to neutral surfaces. We discuss a few possible explanations for this desorption transition. Finally, we observe that the surface tension decreases monotonically with increasing concentration of PSS in bulk solution but is not correlated with the adsorbed amount of PSS at the surface. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Natl Inst Stand & Technol, Gaithersburg, MD USA. Los Alamos Natl Lab, LANSCE, Los Alamos, NM USA. RP Kent, MS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Lujan Center, LANL/G-4896-2012; Ivkov, Robert/A-3902-2015 OI Ivkov, Robert/0000-0002-2930-5276 NR 57 TC 35 Z9 35 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 17 PY 2002 VL 35 IS 26 BP 9737 EP 9747 DI 10.1021/ma0200468 PG 11 WC Polymer Science SC Polymer Science GA 626HB UT WOS:000179864800019 ER PT J AU Pralle, MU Moelders, N McNeal, MP Puscasu, I Greenwald, AC Daly, JT Johnson, EA George, T Choi, DS El-Kady, I Biswas, R AF Pralle, MU Moelders, N McNeal, MP Puscasu, I Greenwald, AC Daly, JT Johnson, EA George, T Choi, DS El-Kady, I Biswas, R TI Photonic crystal enhanced narrow-band infrared emitters SO APPLIED PHYSICS LETTERS LA English DT Article ID EXTRAORDINARY OPTICAL-TRANSMISSION; SUBWAVELENGTH HOLE ARRAYS AB We have experimentally and theoretically developed a unique thermally stimulated midinfrared source that emits radiation within a narrow range of wavelengths (deltalambda/lambdaless than or equal to0.2). The emission wavelengths are defined by the periodicity of a metal coated silicon-air photonic crystal etched into the emitter surface. The lattice of the holes in the metal mediate the coupling of light into discrete surface plasmon states. This yields surfaces with spectrally nonuniform infrared reflection properties where over much of the IR 90+% of photons are reflected yet, in a narrow spectral region, 90% absorption is observed. Transfer matrix calculations simulate well the position and strength of the absorption features. This technology will afford tunable infrared emitters with high power in a narrow spectral band that are critical for sensing, spectroscopy, and thermophotovoltaic applications. (C) 2002 American Institute of Physics. C1 Ion Opt Inc, Waltham, MA 02452 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Iowa State Univ, Ames Lab, Dept Phys, Ames, IA 50011 USA. Iowa State Univ, Microelect Res Ctr, Ames, IA 50011 USA. RP Pralle, MU (reprint author), Ion Opt Inc, Waltham, MA 02452 USA. RI El-Kady, Ihab/D-2886-2013; Choi, Daniel/A-8181-2017 OI El-Kady, Ihab/0000-0001-7417-9814; NR 23 TC 158 Z9 164 U1 6 U2 54 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 DEC 16 PY 2002 VL 81 IS 25 BP 4685 EP 4687 DI 10.1063/1.1526919 PG 3 WC Physics, Applied SC Physics GA 623YB UT WOS:000179731000001 ER PT J AU Leonard, F Tersoff, J AF Leonard, F Tersoff, J TI Dielectric response of semiconducting carbon nanotubes SO APPLIED PHYSICS LETTERS LA English DT Article AB The dielectric response of semiconducting carbon nanotubes is studied within a tight-binding theory. We focus on "zigzag" tubes, finding that the induced charge exhibits large oscillations within the unit cell. The spatial extent of the response function is roughly equal to the nanotube radius, for any radius. We point out that the dielectric constant of undoped tubes (or any low-dimensional semiconductor) is 1. Our results are confirmed by direct numerical calculations. (C) 2002 American Institute of Physics. C1 Sandia Natl Labs, Livermore, CA 94551 USA. IBM Corp, Div Res, TJ Watson Res Ctr, Yorktown Hts, NY 10598 USA. RP Leonard, F (reprint author), Sandia Natl Labs, MS 9161, Livermore, CA 94551 USA. NR 5 TC 52 Z9 52 U1 1 U2 9 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 16 PY 2002 VL 81 IS 25 BP 4835 EP 4837 DI 10.1063/1.1530373 PG 3 WC Physics, Applied SC Physics GA 623YB UT WOS:000179731000051 ER PT J AU Sui, GD Orbulescu, J Mabrouki, M Leblanc, RM Liu, SG Gregg, BA AF Sui, GD Orbulescu, J Mabrouki, M Leblanc, RM Liu, SG Gregg, BA TI Two-dimensional self-assembly of liquid-crystalline perylene diimide derivatives at the air/water interface SO CHEMPHYSCHEM LA English DT Article DE epifluorescence; liquid crystals; self-assembly; surface chemistry; thin films ID LANGMUIR-BLODGETT-FILMS C1 Univ Miami, Dept Chem, Coral Gables, FL 33124 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Leblanc, RM (reprint author), Univ Miami, Dept Chem, 1301 Mem Dr, Coral Gables, FL 33124 USA. RI MABROUKI, Mustapha/B-2421-2012; Orbulescu, Jhony/D-7829-2012 OI MABROUKI, Mustapha/0000-0001-8975-9803; Orbulescu, Jhony/0000-0001-9408-9787 NR 10 TC 8 Z9 8 U1 1 U2 7 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 1439-4235 J9 CHEMPHYSCHEM JI ChemPhysChem PD DEC 16 PY 2002 VL 3 IS 12 BP 1041 EP 1044 DI 10.1002/cphc.200290008 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 630MR UT WOS:000180112300010 PM 12516217 ER PT J AU Deivanayagam, CCS Wann, ER Chen, W Carson, M Rajashankar, KR Hook, M Narayana, SVL AF Deivanayagam, CCS Wann, ER Chen, W Carson, M Rajashankar, KR Hook, M Narayana, SVL TI A novel variant of the immunoglobulin fold in surface adhesins of Staphylococcus aureus: crystal structure of the fibrinogen-binding MSCRAMM, clumping factor A SO EMBO JOURNAL LA English DT Article DE adhesins; clumping factor A; crystal structure; immunoglobulin fold; Staphylococcus aureus ID PROTEIN-DRIVEN CRYSTALLIZATION; GAMMA-CHAIN; 3-DIMENSIONAL STRUCTURE; SECONDARY STRUCTURE; INTEGRIN-BINDING; LIGAND-BINDING; ALPHA-CHAIN; DOMAIN; RECEPTOR; SITE AB We report here the crystal structure of the minimal ligand-binding segment of the Staphylococcus aureus MSCRAMM, clumping factor A. This fibrinogen-binding segment contains two similarly folded domains. The fold observed is a new variant of the immunoglobulin motif that we have called DE-variant or the DEv-IgG fold. This subgroup includes the ligand-binding domain of the collagen-binding S.aureus MSCRAMM CNA, and many other structures previously classified as jelly rolls. Structure predictions suggest that the four fibrinogen-binding S.aureus MSCRAMMs identified so far would also contain the same DEv-IgG fold. A systematic docking search using the C-terminal region of the fibrinogen gamma-chain as a probe suggested that a hydrophobic pocket formed between the two DEv-IgG domains of the clumping factor as the ligand-binding site. Mutagenic substitution of residues Tyr256, Pro336, Tyr338 and Lys389 in the clumping factor, which are proposed to contact the terminal residues (408)AGDV(411) of the gamma-chain, resulted in proteins with no or markedly reduced affinity for fibrinogen. C1 Univ Alabama, Sch Optometry, Ctr Biophys Sci & Engn, CBSE 244, Birmingham, AL 35294 USA. Texas A&M Univ Syst, Hlth Sci Ctr, Ctr Extracellular Matrix Biol, Inst Biosci & Technol, Houston, TX 77030 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Narayana, SVL (reprint author), Univ Alabama, Sch Optometry, Ctr Biophys Sci & Engn, CBSE 244, 1025 18th St S, Birmingham, AL 35294 USA. FU NIAID NIH HHS [1AI20624, R01 AI020624, R56 AI020624] NR 61 TC 104 Z9 107 U1 0 U2 5 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0261-4189 J9 EMBO J JI Embo J. PD DEC 16 PY 2002 VL 21 IS 24 BP 6660 EP 6672 DI 10.1093/emboj/cdf619 PG 13 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 627TJ UT WOS:000179952000004 PM 12485987 ER PT J AU Schreckenbach, G AF Schreckenbach, G TI NMR shielding calculations across the periodic table: Diamagnetic uranium compounds. 2. Ligand and metal NMR SO INORGANIC CHEMISTRY LA English DT Article ID DENSITY-FUNCTIONAL THEORY; INCLUDING ATOMIC ORBITALS; NUCLEAR-MAGNETIC-RESONANCE; REGULAR 2-COMPONENT HAMILTONIANS; INHOMOGENEOUS ELECTRON-GAS; CHEMICAL-SHIFTS; HARTREE-FOCK; VIBRATIONAL FREQUENCIES; CORRELATION-ENERGY; ACTINIDE COMPOUNDS AB In this and a previous article (J. Phys. Chem. A 2000, 104, 8244), the range of application for relativistic density functional theory (DFT) is extended to the calculation of nuclear magnetic resonance (NMR) shieldings and chemical shifts in diamagnetic actinide compounds. Two relativistic DFT methods are used, ZORA ("zeroth-order regular approximation") and the quasirelativistic (QR) method. In the given second paper, NMR shieldings and chemical shifts are calculated and discussed for a wide range of compounds. The molecules studied comprise uranyl complexes, [UO2Ln](+/-q); UF6; inorganic UF6 derivatives, UF6-nCln, n = 0-6; and organometallic UF6 derivatives, UF6-n(OCH3)(n), n = 0-5. Uranyl complexes include [UO2F4](2-), [UO2Cl4](2-), [UO2(OH)(4)](2-), [UO2(CO3)(3)](4-), and [UO2(H2O)(5)](2+). For the ligand NMR, moderate (e.g., F-19 NMR chemical shifts in UF6-nCln) to excellent agreement [e,g., 19F chemical shift tensor in UF6 or H-1 NMR in UF6-n(OCH3)(n)] has been found between theory and experiment. The methods have been used to calculate the experimentally unknown U-235 NMR chemical shifts. A large chemical shift range of at least 21000 ppm has been predicted for the U-235 nucleus. ZORA spin-orbit appears to be the most accurate method for predicting actinide metal chemical shifts. Trends in the U-235 NMR chemical shifts of UF6-nLn molecules are analyzed and explained in terms of the calculated electronic structure. It is argued that the energy separation and interaction between occupied and virtual orbitals with f-character are the determining factors. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Seaborg Inst Transactinium Sci, Los Alamos, NM 87545 USA. RP Concordia Univ, Dept Chem & Biochem, 1455 Maisonneuve Blvd W, Montreal, PQ H3G 1M8, Canada. EM schrecke@alcor.concordia.ca NR 95 TC 23 Z9 23 U1 1 U2 11 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 DEC 16 PY 2002 VL 41 IS 25 BP 6560 EP 6572 DI 10.1021/ic020370j PG 13 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 625BU UT WOS:000179797700007 PM 12470051 ER PT J AU Kadish, KM Lin, M Van Caemelbecke, E De Stefano, G Medforth, CJ Nurco, DJ Nelson, NY Krattinger, B Muzzi, CM Jaquinod, L Xu, Y Shyr, DC Smith, KM Shelnutt, JA AF Kadish, KM Lin, M Van Caemelbecke, E De Stefano, G Medforth, CJ Nurco, DJ Nelson, NY Krattinger, B Muzzi, CM Jaquinod, L Xu, Y Shyr, DC Smith, KM Shelnutt, JA TI Influence of electronic and structural effects on the oxidative behavior of nickel porphyrins SO INORGANIC CHEMISTRY LA English DT Article ID PARA-SUBSTITUTED TETRAPHENYLPORPHYRIN; PI-ANION RADICALS; NONPLANAR PORPHYRINS; ELECTROCHEMICAL PROPERTIES; SPECTROSCOPIC PROPERTIES; METAL DEPENDENCE; RESONANCE RAMAN; MESO-TETRAPHENYLPORPHYRINS; CONFORMATIONAL FLEXIBILITY; MOLECULAR-STRUCTURE AB With the aim of better understanding the electronic and structural factors which govern electron-transfer processes in porphyrins the electrochemistry of 29 nickel(II) porphyrins has been examined in dichloromethane containing either 0.1 M tetra-n-butylammonium perchlorate (TBAP) or tetra-n-butylammonium hexafluorophosphate (TBAPF(6)) as supporting electrolyte. Half-wave potentials for the first oxidation and first reduction are only weakly dependent on the supporting electrolyte, but E-1/2 for the second oxidation varies considerably with the type of supporting electrolyte. E-1/2 values for the first reduction to give a porphyrin pi-anion radical are effected in large part by the electronic properties of the porphyrin macrocycle substituents, while half-wave potentials for the first oxidation to give a pi-cation radical are affected by the substituents as well as by nonplanar deformations of the porphyrin macrocycle. The potential difference between the first and second oxidations (Delta\Ox(2) - Ox(1)\) is highly variable among the 29 investigated compounds and ranges from 0 mV (two overlapped oxidations) to 460 mV depending on the macrocycle substituents and the anion of the supporting electrolyte. The magnitude of Delta\Ox(2) - Ox(1)\ is generally smaller for compounds with very electron-withdrawing substituents and when TBAP is used as the supporting electrolyte. This behavior is best explained in terms of differences in the binding strengths of anions from the supporting electrolyte (ClO4- or PF6-) to the doubly oxidized species. A closer analysis suggests two factors which are important in modulating Delta\Ox(2) - Ox(1)\ and thus the binding affinity of the anion to the porphyrin dication. One is the type of T-cation radical (a proxy for the charge distribution in the dication), and the other is the conformation of the porphyrin macrocycle (either planar or nonplanar). These findings imply that the redox behavior of porphyrins can be selectively tuned to display separate or overlapped oxidation processes. C1 Univ Houston, Dept Chem, Houston, TX 77204 USA. Houston Baptist Univ, Dept Chem, Houston, TX 77074 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. Sandia Natl Labs, Biomol Mat & Interfaces Dept, Albuquerque, NM 87185 USA. Univ Georgia, Dept Chem, Athens, GA 30602 USA. RP Kadish, KM (reprint author), Univ Houston, Dept Chem, Houston, TX 77204 USA. RI Shelnutt, John/A-9987-2009; Medforth, Craig/D-8210-2013; REQUIMTE, FMN/M-5611-2013; REQUIMTE, UCIBIO/N-9846-2013 OI Shelnutt, John/0000-0001-7368-582X; Medforth, Craig/0000-0003-3046-4909; FU NHLBI NIH HHS [HL 22252] NR 86 TC 65 Z9 66 U1 0 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 16 PY 2002 VL 41 IS 25 BP 6673 EP 6687 DI 10.1021/ic0200702 PG 15 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 625BU UT WOS:000179797700018 PM 12470062 ER PT J AU Bean, AC Xu, YW Danis, JA Albrecht-Schmitt, TE Scott, BL Runde, W AF Bean, AC Xu, YW Danis, JA Albrecht-Schmitt, TE Scott, BL Runde, W TI Aqueous reactions of U(VI) at high chloride concentrations: Syntheses and structures of new uranyl chloride polymers SO INORGANIC CHEMISTRY LA English DT Article ID BOND-VALENCE PARAMETERS; CRYSTAL-STRUCTURE; COMPLEXES; IODATES; URANIUM AB The reactions of UO3 with acidic aqueous chloride solutions resulted in the formation of two new polymeric U(VI) compounds. Single crystals Of Cs-2[(UO2)(3)Cl-2(IO3)(OH)O-2].2H(2)O (1) were formed under hydrothermal conditions with HlO(3) and CsCl, and Li(H2O)(2)[(UO2)(2)Cl-3(O)(H2O)] (2) was obtained from acidic LiCl solutions under ambient temperature and pressure. Both compounds contain pentagonal bipyramidal coordination of the uranyl dication, UO22+. The structure of 1 consists of infinite [(UO2)(3)Cl-2(IO3)(mu(3)-OH)(mu(3)-O)(2)](2-) ribbons that run down the b axis that are formed from edge-sharing pentagonal bipyramidal [UO6Cl] and [UO5Cl2] units. The Cs+ cations separate the chains from one another and form long ionic contacts with terminal oxygen atoms from iodate ligands, uranyl oxygen atoms, water molecules, and chloride anions. In 2, edge-sharing [UO3Cl4] and [UO5Cl2] units build up tetranuclear [(UO2)(4)(mu-Cl)(6)(mu(3)-O)(2)(H2O)(2)](2-) anions that are bridged by chloride to form one-dimensional chains. These chains are connected in a complex network of hydrogen bonds and interactions of uranyl oxygen atoms with Li+ cations. Crystal data: 1, orthorhombic, space group Prima, a = 8.2762(4) Angstrom, b = 12.4809(6) Angstrom, c 17.1297(8) Angstrom, Z = 4; 2, triclinic, space group P (1) over bar, a = 8.110(1) Angstrom, b = 8.621 (1) Angstrom, c = 8.740(1) Angstrom, Z = 2. C1 Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Auburn Univ, Dept Chem, Auburn, AL 36849 USA. RP Runde, W (reprint author), Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 20 TC 39 Z9 39 U1 2 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 16 PY 2002 VL 41 IS 25 BP 6775 EP 6779 DI 10.1021/ic020177p PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 625BU UT WOS:000179797700030 PM 12470074 ER PT J AU Beckman, SP Xu, X Specht, P Weber, ER Kisielowski, C Chrzan, DC AF Beckman, SP Xu, X Specht, P Weber, ER Kisielowski, C Chrzan, DC TI Ab initio prediction of the structure of glide set dislocation cores in GaAs SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT Conference on Extended Defects in Semiconductors (EDS 2002) CY JUN 01-06, 2002 CL BOLOGNA, ITALY ID 90-DEGREES PARTIAL DISLOCATION; TRANSMISSION ELECTRON-MICROSCOPY; TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; RECONSTRUCTION; SEMICONDUCTORS; RESOLUTION; SILICON; PSEUDOPOTENTIALS; ELEMENTS AB The structures of the glide set partial dislocations in GaAs are predicted using an ab initio electronic structure total energy method employing ultrasoft pseudopotentials. The single- and double-period reconstructions of the 90degrees partial dislocations are found to be nearly degenerate in energy. The structure of the 30degrees beta-dislocation is found to agree qualitatively with an experimentally determined structure. C1 Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Chrzan, DC (reprint author), Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. NR 34 TC 17 Z9 17 U1 2 U2 10 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 16 PY 2002 VL 14 IS 48 BP 12673 EP 12680 AR PII S0953-8984(02)54141-2 DI 10.1088/0953-8984/14/48/302 PG 8 WC Physics, Condensed Matter SC Physics GA 630CZ UT WOS:000180091100003 ER PT J AU Hull, R Gray, J Wu, CC Atha, S Floro, JA AF Hull, R Gray, J Wu, CC Atha, S Floro, JA TI Interaction between surface morphology and misfit dislocations as strain relaxation modes in lattice-mismatched heteroepitaxy SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT Conference on Extended Defects in Semiconductors (EDS 2002) CY JUN 01-06, 2002 CL BOLOGNA, ITALY ID GEXSI1-X/SI(100) HETEROSTRUCTURES; SI1-XGEX/SI HETEROSTRUCTURES; EPITAXIAL MULTILAYERS; GROWTH; NUCLEATION; GE; TRANSITION; EVOLUTION; KINETICS; PYRAMIDS AB We show how strained layer heteroepitaxial systems can serve as model systems for the study of dislocation energetics and kinetics in semiconductors through the introduction of strain-relieving misfit dislocation arrays. Such structures allow fundamental dislocation properties to be studied at carefully controlled stresses in the range 10(7)-10(9) Pa. A parallel strain relaxation mode in strained heterostructures is via coherent islanding or surface roughening of the epitaxial layer. This mechanism acts both in competition and in cooperation with injection of misfit dislocations. and provides a further degree of control for study of the fundamental energetic and kinetic properties of dislocations. Using ultra-sensitive in situ wafer curvature measurements of stress during molecular beam epitaxy growth of GexSi1-x/Si heterostructures, the relative contributions of surface roughening and dislocation injection to strain relaxation may be qualitatively and quantitatively assessed. In addition, a new strain-stabilized morphology, 'quantum fortresses', comprising cooperative island nucleation around shallow strain-relieving pits, is identified during Ge0.3Si0.7/Si(100) heteroepitaxy. This configuration has potential application to nanoelectronic device architectures. C1 Univ Virginia, Dept Mat Sci, Charlottesville, VA 22902 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hull, R (reprint author), Univ Virginia, Dept Mat Sci, 116 Engineers Way, Charlottesville, VA 22902 USA. NR 31 TC 21 Z9 21 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 16 PY 2002 VL 14 IS 48 BP 12829 EP 12841 AR PII S0953-8984(02)54034-0 DI 10.1088/0953-8984/14/48/323 PG 13 WC Physics, Condensed Matter SC Physics GA 630CZ UT WOS:000180091100024 ER PT J AU Vyvenko, OF Buonassisi, T Istratov, AA Weber, ER Kittler, M Seifert, W AF Vyvenko, OF Buonassisi, T Istratov, AA Weber, ER Kittler, M Seifert, W TI Application of synchrotron-radiation-based x-ray microprobe techniques for the analysis of recombination activity of metals precipitated at Si/SiGe misfit dislocations SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT Conference on Extended Defects in Semiconductors (EDS 2002) CY JUN 01-06, 2002 CL BOLOGNA, ITALY ID SILICON; SEMICONDUCTOR; CONTAMINATION AB In this study we report application of synchrotron-radiation-based x-ray microprobe techniques (the x-ray-beam-induced current (XBIC) and x-ray fluorescence (mu-XRF) methods) to the analysis of the recombination activity and space distribution of copper and iron in the vicinity of dislocations in silicori/silicon-germanium structures. A combination of these two techniques enables one to study the chemical nature of the defects and impurities and their recombination activity in situ and to map metal clusters with a micron-scale resolution. XRF analysis revealed that copper formed clearly distinguishable precipitates along the misfit dislocations. A proportional dependence between the XBIC contrast and the number of copper atoms in the precipitates was established. In hydrogen-passivated iron-contaminated samples we observed clusters of iron precipitates which had no recombination activity detectable by the XBIC technique as well as iron clusters which were not completely passivated. C1 Univ Calif Berkeley, LBNL, Berkeley, CA 94720 USA. IHP, D-15236 Frankfurt, Germany. RP Vyvenko, OF (reprint author), Univ Calif Berkeley, LBNL, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Buonassisi, Tonio/J-2723-2012; Vyvenko, Oleg/I-6539-2013 OI Vyvenko, Oleg/0000-0001-6077-3679 NR 14 TC 18 Z9 18 U1 2 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 16 PY 2002 VL 14 IS 48 BP 13079 EP 13086 AR PII S0953-8984(02)54062-5 DI 10.1088/0953-8984/14/48/353 PG 8 WC Physics, Condensed Matter SC Physics GA 630CZ UT WOS:000180091100054 ER PT J AU Look, DC Jones, RL Sun, XL Brillson, LJ Ager, JW Park, SS Han, JH Molnar, RM Maslar, JE AF Look, DC Jones, RL Sun, XL Brillson, LJ Ager, JW Park, SS Han, JH Molnar, RM Maslar, JE TI Electrical and optical properties of GaN/Al2O3 interfaces SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT Conference on Extended Defects in Semiconductors (EDS 2002) CY JUN 01-06, 2002 CL BOLOGNA, ITALY ID VAPOR-PHASE EPITAXY; ELECTRONIC-STRUCTURE; GAN; FILMS; LUMINESCENCE; DISLOCATION AB Hall-effect, photoluminescence (PL), cathodoluminescence (CL), and Raman scattering measurements have been used to characterize the Ga (top) and N (bottom) faces of free-standing GaN layers grown by hydride vapour phase epitaxy on Al2O3. The material near the bottom has higher carrier concentration, lower mobility, larger PL linewidths, brighter CL emission, and stronger Raman plasmon-phonon lines than the material near the top. All results are consistent with the diffusion of O from the Al2O3 substrate, sometimes covering a distance of several tens of micrometres. The O donor is compensated by Ga vacancy acceptors, known to exist from positron annihilation experiments. However, Raman and CL profiling show that the poor interface region ends rather abruptly, giving excellent material near the top (Ga) face. C1 USAF, Res Lab, MLPS, Wright Patterson AFB, OH 45433 USA. Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. Ohio State Univ, Dept Elect Engn, Columbus, OH 43210 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Samsung Adv Inst Technol, Suwon 440600, South Korea. MIT, Lincoln Lab, Lexington, MA 02420 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Look, DC (reprint author), USAF, Res Lab, MLPS, Wright Patterson AFB, OH 45433 USA. OI Ager, Joel/0000-0001-9334-9751 NR 16 TC 18 Z9 18 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 16 PY 2002 VL 14 IS 48 BP 13337 EP 13344 AR PII S0953-8984(02)54171-0 DI 10.1088/0953-8984/14/48/386 PG 8 WC Physics, Condensed Matter SC Physics GA 630CZ UT WOS:000180091100087 ER PT J AU Servant, G Tait, TMP AF Servant, G Tait, TMP TI Elastic scattering and direct detection of Kaluza-Klein dark matter SO NEW JOURNAL OF PHYSICS LA English DT Article ID EXTRA DIMENSIONS; BREAKING; SYMMETRY AB Recently a new dark-matter candidate has been proposed as a consequence of universal compact extra dimensions. It was found that to account for cosmological observations, the masses of the first Kaluza-Klein (KK) modes (and thus the approximate size of the extra dimension) should be in the range 600-1200 GeV when the lightest Kaluza-Klein particle (LKP) corresponds to the hypercharge boson and in the range 1-1.8 TeV when it corresponds to a neutrino. In this paper, we compute the elastic scattering cross sections between KK dark matter and nuclei both when the LKP is a KK mode of a weak gauge boson, and when it is a neutrino. We include nuclear form factor effects which are important to take into account due to the large LKP masses favoured by estimates of the relic density. We present both differential and integrated rates for present and proposed germanium, NaI and xenon detectors. Observable rates at current detectors are typically less than one event per year, but the next generation of detectors can probe a significant fraction of the relevant parameter space. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. EM servant@theory.uchicago.edu; tait@fnal.gov NR 29 TC 142 Z9 142 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 1367-2630 J9 NEW J PHYS JI New J. Phys. PD DEC 16 PY 2002 VL 4 AR 99 DI 10.1088/1367-2630/4/1/399 PG 19 WC Physics, Multidisciplinary SC Physics GA 627DE UT WOS:000179914900001 ER PT J AU Bertulani, CA Hammer, HW van Kolck, U AF Bertulani, CA Hammer, HW van Kolck, U TI Effective field theory for halo nuclei: shallow p-wave states SO NUCLEAR PHYSICS A LA English DT Article DE effective field theory; shallow p-wave states; halo nuclei ID BIG-BANG NUCLEOSYNTHESIS; SHORT-RANGE INTERACTIONS; CHIRAL LAGRANGIANS; DEUTERON SCATTERING; FORCES; COULOMB; ENERGY; SYSTEM AB Halo nuclei are a promising new arena for studies based on effective field theory (EFT). We develop an EFT for shallow p-wave states and discuss the application to elastic nalpha scattering. In contrast to the s-wave case, both the scattering length and effective range enter at leading order. We also discuss the prospects of using EFT in the description of other halos, such as the three-body halo nucleus He-6. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. RP Bertulani, CA (reprint author), Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. NR 44 TC 116 Z9 116 U1 0 U2 2 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 DEC 16 PY 2002 VL 712 IS 1-2 BP 37 EP 58 AR PII S0375-9474(02)01270-8 DI 10.1016/S0375-9474(02)01270-8 PG 22 WC Physics, Nuclear SC Physics GA 615YG UT WOS:000179274500004 ER PT J AU Magas, VK Csernai, LP Strottman, D AF Magas, VK Csernai, LP Strottman, D TI Effective string rope model for the initial stages of ultra-relativistic heavy ion collisions SO NUCLEAR PHYSICS A LA English DT Article DE ultra-relativistic heavy ion collisions; initial state; string ropes; RHIC; third flow ID NUCLEUS-NUCLEUS COLLISIONS; QUARK-GLUON PLASMA; FREEZE-OUT MODELS; ELLIPTIC FLOW; TRANSVERSE ENERGY; CENTRALITY DEPENDENCE; AU+AU COLLISIONS; PHASE-TRANSITION; PARTICLE DISTRIBUTIONS; FLUID-DYNAMICS AB Different approaches to describe initial stages of relativistic heavy ion collisions are discussed qualitatively and quantitatively. An effective string rope model is presented for heavy ion collisions at RHIC energies. Our model takes into account baryon recoil for both target and projectile, arising from the acceleration of partons in an effective field, F-munu, produced in the collision. The typical field strength (string tension) for RHIC energies is about 5-12 GeV/fm, what allows us to talk about "string ropes". The results show that a QGP forms a tilted disk, such that the direction of the largest pressure gradient stays in the reaction plane, but deviates from both the beam and the usual transverse flow directions. The produced initial state can be used as an initial condition for further hydrodynamical calculations. Such initial conditions lead to the creation of third flow component. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Inst Super Tecn, Ctr Phys Fundamental Interact, Dept Phys, P-1049001 Lisbon, Portugal. Univ Bergen, Dept Phys, Sect Theoret & Computat Phys, N-5007 Bergen, Norway. KFKI, Res Inst Particle & Nucl Phys, H-1525 Budapest, Hungary. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87454 USA. RP Magas, VK (reprint author), Inst Super Tecn, Ctr Phys Fundamental Interact, Dept Phys, Av Rovisco Pais, P-1049001 Lisbon, Portugal. RI Magas, Volodymyr/J-8599-2016 OI Magas, Volodymyr/0000-0003-3701-8362 NR 98 TC 47 Z9 47 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 DEC 16 PY 2002 VL 712 IS 1-2 BP 167 EP 204 AR PII S0375-9474(02)01073-4 DI 10.1016/S0375-9474(02)01073-4 PG 38 WC Physics, Nuclear SC Physics GA 615YG UT WOS:000179274500010 ER PT J AU Demos, SG Staggs, M Minoshima, K Fujimoto, J AF Demos, SG Staggs, M Minoshima, K Fujimoto, J TI Characterization of laser induced damage sites in optical components SO OPTICS EXPRESS LA English DT Article ID LIGHT-SCATTERING TOMOGRAPHY; VISIBLE PHOTOLUMINESCENCE; COHERENCE TOMOGRAPHY; SILICA; SURFACE; GLASS; DIELECTRICS; IRRADIATION; CLUSTERS; CRYSTALS AB Optical components for large-aperture laser systems may contain a number of defect ( damage) sites formed as a result of exposure to the propagating laser beam. When exposed to high-power laser irradiation, a number of damage sites tend to grow. In this work, we explore fluorescence microscopy and optical coherence tomography for the characterization of such defect sites. Fluorescence microscopy demonstrates the presence of a layer of highly emissive, and therefore absorbing, modified material. Optical coherence tomography can image the network of cracks formed around the core of the damage site. This information may be useful for the application of a mitigation process to prevent damage growth. (C) 2002 Optical Society of America. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. MIT, Dept Elect Engn & Comp Sci, Cambridge, MA 02139 USA. MIT, Elect Res Lab, Cambridge, MA 02139 USA. RP Demos, SG (reprint author), Lawrence Livermore Natl Lab, POB 808,L-411, Livermore, CA 94551 USA. EM Demos1@llnl.gov; Staggs3@llnl.gov; k.minoshima@aist.go.jp; jgfuji@MIT.EDU RI Minoshima, Kaoru/G-1435-2013 NR 26 TC 52 Z9 53 U1 1 U2 16 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 DEC 16 PY 2002 VL 10 IS 25 BP 1444 EP 1450 DI 10.1364/OE.10.001444 PG 7 WC Optics SC Optics GA 626CT UT WOS:000179855300001 PM 19461677 ER PT J AU Kumar, VVRK George, AK Reeves, WH Knight, JC Russell, PS Omenetto, FG Taylor, AJ AF Kumar, VVRK George, AK Reeves, WH Knight, JC Russell, PS Omenetto, FG Taylor, AJ TI Extruded soft glass photonic crystal fiber for ultrabroad supercontinuum generation SO OPTICS EXPRESS LA English DT Article ID ANOMALOUS-DISPERSION; OPTICAL-FIBER AB We report the fabrication and properties of soft glass photonic crystal fibers (PCF's) for supercontinuum generation. The fibers have zero or anomalous group velocity dispersion at wavelengths around 1550 nm, and approximately an order of magnitude higher nonlinearity than attainable in comparable silica fibers. We demonstrate the generation of an ultrabroad supercontinuum spanning at least 350 nm to 2200 nm using a 1550 nm ultrafast pump source. (C) 2002 Optical Society of America. C1 Univ Bath, Dept Phys, Optoelect Grp, Bath BA2 7AY, Avon, England. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kumar, VVRK (reprint author), Univ Bath, Dept Phys, Optoelect Grp, Claverton Down, Bath BA2 7AY, Avon, England. EM pysrkk@bath.ac.uk; omenetto@lanl.gov RI Knight, Jonathan/D-3879-2011; Russell, Philip/G-5132-2012 OI Knight, Jonathan/0000-0002-0802-8804; Russell, Philip/0000-0002-8972-2477 NR 11 TC 160 Z9 166 U1 2 U2 23 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 DEC 16 PY 2002 VL 10 IS 25 BP 1520 EP 1525 DI 10.1364/OE.10.001520 PG 6 WC Optics SC Optics GA 626CT UT WOS:000179855300011 PM 19461687 ER PT J AU Gao, JB Tung, WW Rao, N AF Gao, JB Tung, WW Rao, N TI Noise-induced Hopf-bifurcation-type sequence and transition to chaos in the Lorenz equations SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIRECT DYNAMICAL TEST; STOCHASTIC RESONANCE; TIME-SERIES; COEXISTING ATTRACTORS; DETERMINISTIC CHAOS; VISUAL-PERCEPTION; SYSTEM; LASER; MODEL; MULTISTABILITY AB We study the effects of noise on the Lorenz equations in the parameter regime admitting two stable fixed point solutions and a strange attractor. We show that noise annihilates the two stable fixed point attractors and evicts a Hopf-bifurcation-like sequence and transition to chaos. The noise-induced oscillatory motions have very well defined period and amplitude, and this phenomenon is similar to stochastic resonance, but without a weak periodic forcing. When the noise level exceeds certain threshold value but is not too strong, the noise-induced signals enable an objective computation of the largest positive Lyapunov exponent, which characterize the signals to be truly chaotic. C1 Univ Florida, Dept Elect & Comp Engn, Gainesville, FL 32611 USA. Univ Calif Los Angeles, Dept Atmospher Sci, Los Angeles, CA 90095 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Gao, JB (reprint author), Univ Florida, Dept Elect & Comp Engn, EB 559, Gainesville, FL 32611 USA. NR 36 TC 28 Z9 28 U1 1 U2 10 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 DEC 16 PY 2002 VL 89 IS 25 AR 254101 DI 10.1103/PhysRevLett.89.254101 PG 4 WC Physics, Multidisciplinary SC Physics GA 622ZT UT WOS:000179678900021 PM 12484887 ER PT J AU Keblinski, P Nayak, SK Zapol, P Ajayan, PM AF Keblinski, P Nayak, SK Zapol, P Ajayan, PM TI Charge distribution and stability of charged carbon nanotubes SO PHYSICAL REVIEW LETTERS LA English DT Article ID DENSITY; ACCURATE AB Density-functional calculations of charge distribution on negatively and positively charged nanotubes result in charge density profiles characterized by a significant increase of charge density at the tube ends. These results are in quantitative agreement with classical electrostatic analysis, which assumes constant electrostatic potential on the conductive tube surface. At high charging levels, the tube ends are observed to be unstable due to Coulomb repulsion. By combining ab initio calculations with classical electrostatics, we determine, as a function of tube length and geometry of the tube end, the critical voltage beyond which nanotubes are unstable. C1 Rensselaer Polytech Inst, Dept Mat Sci & Engn, Troy, NY 12180 USA. Rensselaer Polytech Inst, Dept Phys, Troy, NY 12180 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Keblinski, P (reprint author), Rensselaer Polytech Inst, Dept Mat Sci & Engn, Troy, NY 12180 USA. RI Zapol, Peter/G-1810-2012 OI Zapol, Peter/0000-0003-0570-9169 NR 20 TC 54 Z9 54 U1 1 U2 14 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 DEC 16 PY 2002 VL 89 IS 25 AR 255503 DI 10.1103/PhysRevLett.89.255503 PG 4 WC Physics, Multidisciplinary SC Physics GA 622ZT UT WOS:000179678900030 PM 12484896 ER PT J AU Muramatsu, H Richichi, SJ Severini, H Skubic, P Dytman, SA Mueller, JA Nam, S Savinov, V Chen, S Hinson, JW Lee, J Miller, DH Pavlunin, V Shibata, EI Shipsey, IPJ Cronin-Hennessy, D Lyon, AL Park, CS Park, W Thorndike, EH Coan, TE Gao, YS Liu, F Maravin, Y Narsky, I Stroynowski, R Artuso, M Boulahouache, C Bukin, K Dambasuren, E Khroustalev, K Mountain, R Nandakumar, R Skwarnicki, T Stone, S Wang, JC Mahmood, AH Csorna, SE Danko, I Bonvicini, G Cinabro, D Dubrovin, M McGee, S Bornheim, A Lipeles, E Pappas, SP Shapiro, A Sun, WM Weinstein, AJ Asner, DM Mahapatra, R Nelson, HN Briere, RA Chen, GP Ferguson, T Tatishvili, G Vogel, H Adam, NE Alexander, JP Berkelman, K Blanc, F Boisvert, V Cassel, DG Drell, PS Duboscq, JE Ecklund, KM Ehrlich, R Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hsu, L Jones, CD Kandaswamy, J Kreinick, DL Magerkurth, A Mahlke-Kruger, H Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Pivarski, J Riley, D Sadoff, AJ Schwarthoff, H Shepherd, MR Thayer, JG Urner, D Valant-Spaight, B Viehhauser, G Warburton, A Weinberger, M Athar, SB Avery, P Breva-Newell, L Potlia, V Stoeck, H Yelton, J Brandenburg, G Kim, DYJ Wilson, R Benslama, K Eisenstein, BI Ernst, J Gollin, GD Hans, RM Karliner, I Lowrey, N Marsh, MA Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Ammar, R Besson, D Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Li, SZ Poling, R Smith, A Stepaniak, CJ Urheim, J Metreveli, Z Seth, KK Tomaradze, A Zweber, P Ahmed, S Alam, MS Jian, L Saleem, M Wappler, F Eckhart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Thayer, JB von Toerne, E Wilksen, T Zoeller, MM AF Muramatsu, H Richichi, SJ Severini, H Skubic, P Dytman, SA Mueller, JA Nam, S Savinov, V Chen, S Hinson, JW Lee, J Miller, DH Pavlunin, V Shibata, EI Shipsey, IPJ Cronin-Hennessy, D Lyon, AL Park, CS Park, W Thorndike, EH Coan, TE Gao, YS Liu, F Maravin, Y Narsky, I Stroynowski, R Artuso, M Boulahouache, C Bukin, K Dambasuren, E Khroustalev, K Mountain, R Nandakumar, R Skwarnicki, T Stone, S Wang, JC Mahmood, AH Csorna, SE Danko, I Bonvicini, G Cinabro, D Dubrovin, M McGee, S Bornheim, A Lipeles, E Pappas, SP Shapiro, A Sun, WM Weinstein, AJ Asner, DM Mahapatra, R Nelson, HN Briere, RA Chen, GP Ferguson, T Tatishvili, G Vogel, H Adam, NE Alexander, JP Berkelman, K Blanc, F Boisvert, V Cassel, DG Drell, PS Duboscq, JE Ecklund, KM Ehrlich, R Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hsu, L Jones, CD Kandaswamy, J Kreinick, DL Magerkurth, A Mahlke-Kruger, H Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Pivarski, J Riley, D Sadoff, AJ Schwarthoff, H Shepherd, MR Thayer, JG Urner, D Valant-Spaight, B Viehhauser, G Warburton, A Weinberger, M Athar, SB Avery, P Breva-Newell, L Potlia, V Stoeck, H Yelton, J Brandenburg, G Kim, DYJ Wilson, R Benslama, K Eisenstein, BI Ernst, J Gollin, GD Hans, RM Karliner, I Lowrey, N Marsh, MA Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Ammar, R Besson, D Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Li, SZ Poling, R Smith, A Stepaniak, CJ Urheim, J Metreveli, Z Seth, KK Tomaradze, A Zweber, P Ahmed, S Alam, MS Jian, L Saleem, M Wappler, F Eckhart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Thayer, JB von Toerne, E Wilksen, T Zoeller, MM CA CLEO Collaboration TI Dalitz analysis of D-0 -> K-S(0)pi(+)pi(-) SO PHYSICAL REVIEW LETTERS LA English DT Article ID -> PI(-)PI(+)PI(+) DECAY; NONLEPTONIC DECAYS; 2-BODY DECAYS; CHARM MESONS; DETECTOR AB In e(+)e(-) collisions using the CLEO detector, we have studied the decay of the D-0 to the final state K(S)(0)pi(+)pi(-) with the initial flavor of the D-0 tagged by the decay D*+-->D(0)pi(+). We use the Dalitz technique to measure the resonant substructure in this final state and clearly observe ten different contributions by fitting for their amplitudes and relative phases. We observe a K-*(892)(+)pi(-) component which arises from doubly Cabibbo suppressed decays or D-0-(D-0) over bar mixing. C1 Univ Oklahoma, Norman, OK 73019 USA. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Univ Texas Pan Amer, Edinburg, TX 78539 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Toronto, ON M5S 1A7, Canada. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. Northwestern Univ, Evanston, IL 60208 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Muramatsu, H (reprint author), Univ Oklahoma, Norman, OK 73019 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014; Vogel, Helmut/N-8882-2014; Ferguson, Thomas/O-3444-2014 OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039; Vogel, Helmut/0000-0002-6109-3023; Ferguson, Thomas/0000-0001-5822-3731 NR 25 TC 103 Z9 104 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 DEC 16 PY 2002 VL 89 IS 25 AR 251802 DI 10.1103/PhysRevLett.89.251802 PG 5 WC Physics, Multidisciplinary SC Physics GA 622ZT UT WOS:000179678900008 PM 12484874 ER PT J AU Kelly, JJ Chernov, BK Tovstanovsky, I Mirzabekov, AD Bavykin, SG AF Kelly, JJ Chernov, BK Tovstanovsky, I Mirzabekov, AD Bavykin, SG TI Radical-generating coordination complexes as tools for rapid and effective fragmentation and fluorescent labeling of nucleic acids for microchip hybridization SO ANALYTICAL BIOCHEMISTRY LA English DT Article DE DNA; RNA; labeling; fragmentation; radicals; 1,10-phenanthroline-Cu; Fe-EDTA; coordination complexes ID DENSITY OLIGONUCLEOTIDE ARRAYS; PROTEIN CROSS-LINKING; GENE-EXPRESSION; DNA ARRAYS; HYDROGEN ABSTRACTION; CHEMICAL NUCLEASES; MUTATION DETECTION; STRAND SCISSION; IN-VITRO; IDENTIFICATION AB DNA microchip technology is a rapid, high-throughput method for nucleic acid hybridization reactions. This technology requires random fragmentation and fluorescent labeling of target nucleic acids prior to hybridization. Radical-generating coordination complexes, such as 1,10-phenanthroline-Cu(II) (OP-Cu) and Fe(II)-EDTA (Fe-EDTA), have been commonly used as sequence nonspecific "chemical nucleases" to introduce single-strand breaks in nucleic acids. Here we describe a new method based on these radical-generating complexes for random fragmentation and labeling of both single- and double-stranded forms of RNA and DNA. Nucleic acids labeled with the OP-Cu and the Fe-EDTA protocols revealed high hybridization specificity in hybridization with DNA microchips containing oligonucleotide probes selected for identification of 16S rRNA sequences of the Bacillus group microorganisms. We also demonstrated cDNA- and cRNA-labeling and fragmentation with this method. Both the OP-Cu and Fe-EDTA fragmentation and labeling procedures are quick and inexpensive compared to other commonly used methods. A column-based version of the described method does not require centrifugation and therefore is promising for the automation of sample preparations in DNA microchip technology as well as in other nucleic acid hybridization studies. (C) 2002 Elsevier Science (USA). All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Northwestern Univ, Dept Civil Engn, Evanston, IL 60208 USA. VA Engelhardt Mol Biol Inst, Moscow 117984, Russia. RP Bavykin, SG (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Kelly, John/0000-0002-0894-137X NR 52 TC 25 Z9 29 U1 0 U2 3 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 DEC 15 PY 2002 VL 311 IS 2 BP 103 EP 118 AR PII S0003-2697(02)00388-3 DI 10.1016/S0003-2697(02)00388-3 PG 16 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 625PL UT WOS:000179824800001 PM 12470669 ER PT J AU Wahl, KL Wunschel, SC Jarman, KH Valentine, NB Petersen, CE Kingsley, MT Zartolas, KA Saenz, AJ AF Wahl, KL Wunschel, SC Jarman, KH Valentine, NB Petersen, CE Kingsley, MT Zartolas, KA Saenz, AJ TI Analysis of microbial mixtures by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID RAPID IDENTIFICATION; BACTERIA AB Many different laboratories are currently developing mass-spectrometric techniques to analyze and identify microorganisms. However, minimal work has been done with mixtures of bacteria. To demonstrate that microbial mixtures could be analyzed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), mixed bacterial cultures were analyzed in a double-blind fashion. Nine different bacterial species currently in our MALDI-MS fingerprint library were used to generate 50 different simulated mixed bacterial cultures similar to that done for an initial blind study previously reported (Jarman, K. H.; Cebula, S. T.; Saenz, A. J.; Petersen, C. E.; Valentine, N. B.; Kingsley, M. T.; Wahl, K. L. Anal. Chem. 2000, 72, 1217-1223). The samples were analyzed by MALDI-MS with automated data extraction and analysis algorithms developed in our laboratory. The components present in the sample were identified correctly to the species level in all but one of the samples. However, correctly eliminating closely related organisms was challenging for the current algorithms, especially in differentiating Serratia marcescens, Escherichia coli, and Yersinia enterocolitica, which have some similarities in their MALDI-MS fingerprints. Efforts to improve the specificity of the algorithms are in progress. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wahl, KL (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 10 TC 100 Z9 103 U1 2 U2 17 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 DEC 15 PY 2002 VL 74 IS 24 BP 6191 EP 6199 DI 10.1021/ac0203847 PG 9 WC Chemistry, Analytical SC Chemistry GA 628AG UT WOS:000179969000009 PM 12510738 ER PT J AU Van Berkel, GJ Sanchez, AD Quirke, JME AF Van Berkel, GJ Sanchez, AD Quirke, JME TI Thin-layer chromatography and electrospray mass spectrometry coupled using a surface sampling probe SO ANALYTICAL CHEMISTRY LA English DT Article ID LASER-DESORPTION IONIZATION; PLANAR CHROMATOGRAPHY; SEPARATIONS; MS AB A combined surface sampling probe/electrospray emitter was used for the direct readout of thin-layer chromatography plates by electrospray mass spectrometry. The technique was demonstrated with reversed-phase C18 plates using a three-dye mixture composed of methylene blue, crystal violet, and rhodamine 6G for positive ion mode detection and a separate dye mixture containing fluorescein, naphthol blue black, and fast green FCF for negative ion mode detection. Acquisition of mass spectra of components of individual bands on the plate was shown by manual stepping to and sampling from specific locations within the bands. Computer-controlled scanning of development lanes on the plate was illustrated by using multiple ion monitoring in both positive and negative ion modes. Commercial TLC plates were used and no post-separation processing other than drying of the plates was required prior to mass spectrometric analysis. Readout resolution, the limits of scan speed, detection levels, TLC phase, and eluting solvents were investigated and discussed. C1 Oak Ridge Natl Lab, Div Chem Sci, Organ & Biol Mass Spectrometry Grp, Oak Ridge, TN 37831 USA. Florida Int Univ, Dept Chem, Miami, FL 33199 USA. RP Van Berkel, GJ (reprint author), Oak Ridge Natl Lab, Div Chem Sci, Organ & Biol Mass Spectrometry Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 21 TC 104 Z9 105 U1 4 U2 45 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 DEC 15 PY 2002 VL 74 IS 24 BP 6216 EP 6223 DI 10.1021/ac020540+ PG 8 WC Chemistry, Analytical SC Chemistry GA 628AG UT WOS:000179969000012 PM 12510741 ER PT J AU Chiarappa-Zucca, ML Dingley, KH Roberts, ML Velsko, CA Love, AH AF Chiarappa-Zucca, ML Dingley, KH Roberts, ML Velsko, CA Love, AH TI Sample preparation for quantitation of tritium by accelerator mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID PHARMACEUTICAL RESEARCH; BIOLOGICAL SAMPLES; AMS; EXPOSURE; HYDROGEN; SYSTEM AB The capability to prepare samples accurately and reproducibly for analysis of tritium (H-3) content by accelerator mass spectrometry (AMS) greatly facilitates isotopic tracer studies in which attomole levels of H-3 can be measured in milligram-sized samples. A method has been developed to convert the hydrogen of organic samples to a solid, titanium hydride, which can be analyzed by AMS. Using a two-step process, the sample is first oxidized to carbon dioxide and water. In the second step, the water is transferred within a heated manifold into a quartz tube, reduced to hydrogen gas using zinc, and reacted with titanium powder. The H-3/H-1 ratio of the titanium hydride is measured by AMS and normalized to standards whose ratios were determined by decay counting to calculate the amount of H-3 in the original sample. Water, organic compounds, and biological samples with H-3 activities measured by liquid scintillation counting were utilized to develop and validate the method. The H-3/H-1 ratios were quantified in samples that spanned 5 orders of magnitude, from 10(-10) to 10(-15), with a detection limit of 3.0 x 10(-15), which is equivalent to 0.02 dpm tritium/mg of material. Samples smaller than 2 mg were analyzed following addition of 2 mg of a tritium-free-hydrogen carrier. Preparation of organic standards containing both C-14 and H-3 in 2-mg organic samples demonstrated that this sample preparation methodology can also be applied to quantify both of these isotopes from a single sample. C1 Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. Woods Hole Oceanog Inst, Natl Ocean Sci AMS Facil, Woods Hole, MA 02543 USA. Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. RP Chiarappa-Zucca, ML (reprint author), Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. FU NCRR NIH HHS [RR13461] NR 19 TC 16 Z9 16 U1 1 U2 13 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 DEC 15 PY 2002 VL 74 IS 24 BP 6285 EP 6290 DI 10.1021/ac020295u PG 6 WC Chemistry, Analytical SC Chemistry GA 628AG UT WOS:000179969000021 PM 12510750 ER PT J AU Kang, SH Yeung, ES AF Kang, SH Yeung, ES TI Dynamics of single-protein molecules at a liquid/solid interface: Implications in capillary electrophoresis and chromatography SO ANALYTICAL CHEMISTRY LA English DT Article ID DNA-MOLECULES; R-PHYCOERYTHRIN; FLUORESCENCE MICROSCOPY; ZONE-ELECTROPHORESIS; INDIVIDUAL MOLECULES; SURFACE-DIFFUSION; AQUEOUS-SOLUTION; SUPERCOILED DNA; ADSORPTION; OLIGONUCLEOTIDES AB The behavior of individual molecules of R-phycoerythrin (RPE) was monitored by fluorescence imaging at various pHs and ionic strengths within the evanescent-field layer (EFL) at a water/fused-silica interface. Above the isoelectric point (pI), the individual protein molecules moved between exposures with random motion. As the pH approached the pI of the protein, the RPE molecules were partially adsorbed onto the fused-silica surface. The residence time and the number of molecules within the EFL also increased near the pI. Below the pI, the protein molecules were completely and permanently adsorbed onto the surface. However, the observed number of distinct molecule spots was decreased somewhat because of aggregation. At a given buffer condition, plots of residence times and molecule numbers exhibit asymmetry nearly identical to the corresponding elution peaks of the proteins in capillary electrophoresis and capillary liquid chromatography. These results provide insights into the fundamental interactions for the adsorption/desorption of proteins at the liquid/solid interface. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. NR 50 TC 55 Z9 56 U1 1 U2 17 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 DEC 15 PY 2002 VL 74 IS 24 BP 6334 EP 6339 DI 10.1021/ac0261202 PG 6 WC Chemistry, Analytical SC Chemistry GA 628AG UT WOS:000179969000027 PM 12510756 ER PT J AU Lipert, RJ Shinar, R Vaidya, B Pris, AD Porter, MD Liu, GJ Grabau, TD Dilger, JP AF Lipert, RJ Shinar, R Vaidya, B Pris, AD Porter, MD Liu, GJ Grabau, TD Dilger, JP TI Thin films of block copolymer blends for enhanced performance of acoustic wave-based chemical sensors SO ANALYTICAL CHEMISTRY LA English DT Article ID THICKNESS-SHEAR MODE; QUARTZ-CRYSTAL MICROBALANCE; ATOMIC-FORCE MICROSCOPY; TRIBLOCK COPOLYMERS; RESONATORS; MODULUS; MORPHOLOGY; MASS; VISCOELASTICITY; OSCILLATORS AB The performance of quartz crystal oscillator-based volatile organic compound (VOC) sensors has been enhanced by using coatings made from poly(styrene-block-ethylene-co-butylene-block-styrene) block copolymers blended with resins and homopolymers. Enhanced performance is characterized by a wider operational temperature range (-10 to +50 degreesC) over which the sensors displayed, concurrently, an analyte sensitivity of >0.2 Hz/ppm toluene, minimal energy loss (resistance < 120 ohm), and response times of <20 min (time required to reach 90% of full response). Atomic force microscopy images are consistent with a process in which the additive associates with the polystyrene portions of the microphase-separated block copolymer. This association reinforces the rigidity of the polystyrene network while allowing the rapid uptake of VOCs by the softer polyethylene/butylene phase. C1 Iowa State Univ, Dept Chem, Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Fisher Controls Int Inc, Marshalltown, IA 50158 USA. RP Lipert, RJ (reprint author), Iowa State Univ, Dept Chem, Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. EM blipert@porter1.ameslab.gov RI Lipert, Robert/A-8571-2009 NR 40 TC 10 Z9 10 U1 0 U2 5 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 DEC 15 PY 2002 VL 74 IS 24 BP 6383 EP 6391 DI 10.1021/ac0260490 PG 9 WC Chemistry, Analytical SC Chemistry GA 628AG UT WOS:000179969000034 PM 12510763 ER PT J AU Shroll, RM Straatsma, TP AF Shroll, RM Straatsma, TP TI Molecular structure of the outer bacterial membrane of Pseudomonas aeruginosa via classical simulation SO BIOPOLYMERS LA English DT Article DE outer bacterial membrane; Pseudomonas aeruginosa; parameterized classical simulation model; structural analysis; ligands; calcium ion coordination ID B-BAND LIPOPOLYSACCHARIDE; SEROTYPE O5; METAL-BINDING; STRAIN PAO1; A-BAND; ADHESION; REMOVAL; SURFACE; AK1401; WATER AB A detailed structural analysis has been performed of the outer bacterial membrane of Pseudomonas aeruginosa using a parameterized classical simulation model (R. D. Lins and T. P. Straatsma, Biophysical Journal, 2001, Vol. 81, pp. 1037-1046) with modest modifications. The structural analysis of the membrane is presented and newly discovered characteristics of the membrane are discussed. Simulations indicate that the relative contribution of different ligands to calcium ion coordination varies across the membrane, while maintaining a constant average coordination number of 6.1. Water penetrates the surface of the membrane to a depth of about 30 A. The hydration of ions and phosphate groups is shown to depend on location within the membrane. A measure of saccharide residue orientation is defined and average orientations are presented. Saccharide residues possess varying degrees of motion with a trend of greater mobility at the membrane surface. However, their motion is limited and even in the membrane outer core region the average structure appears fairly rigid over a period of 1 ns. (C) 2002 Wiley Periodicals, Inc. C1 Pacific NW Natl Lab, Computat Biochem Biophys & Biol Grp, Theory Modeling & Simulat Environm Mol Sci Lab, Richland, WA 99352 USA. RP Straatsma, TP (reprint author), Pacific NW Natl Lab, Computat Biochem Biophys & Biol Grp, Theory Modeling & Simulat Environm Mol Sci Lab, Richland, WA 99352 USA. NR 37 TC 29 Z9 29 U1 0 U2 2 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0006-3525 J9 BIOPOLYMERS JI Biopolymers PD DEC 15 PY 2002 VL 65 IS 6 BP 395 EP 407 DI 10.1002/bip.10279 PG 13 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 618FJ UT WOS:000179407800003 PM 12434428 ER PT J AU Rauf, S Ventzek, PLG Abraham, IC Hebner, GA Woodworth, JR AF Rauf, S Ventzek, PLG Abraham, IC Hebner, GA Woodworth, JR TI Charged species dynamics in an inductively coupled Ar/SF6 plasma discharge SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ELECTRON-IMPACT IONIZATION; CROSS-SECTIONS; RF DISCHARGES; SF6; MIXTURES; KINETICS; SILICON; FLUOROCARBON; DISSOCIATION; DENSITIES AB The chemistry of high-density SF6 plasma discharges is not well characterized. In this article, a combination of computational modeling and experimental diagnostics has been utilized to understand charged species dynamics in an inductively coupled Ar/SF6 plasma discharge. The model is based on the two-dimensional Hybrid Plasma Equipment Model with a detailed plasma chemical mechanism for Ar/SF6. In the experiments, absolute electron density and total negative ion density have been measured using microwave interferometry and laser photodetachment, respectively. In addition, we have also utilized prior measurements of mass and energy resolved ion fluxes by Goyette [J. Vac. Sci. Technol. A 19, 1294 (2001)]. Computational results show that all SFx+(x=0-5) ions are present in the plasma discharge. Important negative ions include SF6-, SF5-, and F-. Electron and positive ion densities increase with coil power due to enhanced ionization. However, negative ion densities decrease with coil power as the main negative ion precursor, SF6, is lost through neutral dissociation. An increase in SF6 concentration in the Ar/SF6 gas mixture decreases electron density due to enhanced electron loss through (dissociative) attachment, which enhances negative ion densities. RF bias power does not have an appreciable impact on the ion and electron densities for the parameter range of interest. Experiments show that electron density decreases with gas pressure while the total negative ion density increases up to 25 mTorr. This is due to a decrease in electron temperature, which enhances electron loss through (dissociative) attachment. Although the model is able to capture most of the experimentally observed trends, there are discrepancies regarding the impact of gas pressure on electron density and relative flux of large positive ions. (C) 2002 American Institute of Physics. C1 Motorola Inc, Adv Prod Res & Dev Lab, Semicond Prod Sector, Austin, TX 78721 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Motorola Inc, Adv Prod Res & Dev Lab, Semicond Prod Sector, 3501 Ed Bluestein Blvd,MD K-10, Austin, TX 78721 USA. EM shahid.rauf@motorola.com NR 45 TC 28 Z9 28 U1 0 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 2002 VL 92 IS 12 BP 6998 EP 7007 DI 10.1063/1.1519950 PG 10 WC Physics, Applied SC Physics GA 619UD UT WOS:000179495100007 ER PT J AU Zhao, ZB Yalisove, SM Rek, ZU Bilello, JC AF Zhao, ZB Yalisove, SM Rek, ZU Bilello, JC TI Evolution of anisotropic microstructure and residual stress in sputtered Cr films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID THIN-FILMS; PREFERRED ORIENTATION; X-RAY; TEXTURE; GROWTH; STRAIN; GLASS; MEDIA AB A series of Cr films with varying thicknesses have been prepared using a multiple moving substrate deposition geometry. These films have been investigated with several experimental techniques, including synchrotron x-ray scattering, pole figures, electron microscope, and double crystal diffraction topography. It was found that the in-plane stresses are highly anisotropic in these Cr films. The anisotropic stresses, characterized by two principal stresses in two characteristic directions defined by the deposition geometry, are quantified based on a methodology given in the Appendix. The plan view transmission electron microscopy observations reveal that the Cr films develop well-organized microstructures. The grains, which are elongated along the radial direction, are crystallographically aligned as well. The development of crystallographic texture in the Cr films, further revealed by pole figures and azimuthal (phi) x-ray scans, depends on both the deposition geometry and the film thickness. The preferential orientation of film growth is [110] for thinner films (<1.6 mum), and then becomes [111] for thicker films. Correspondingly, the in-plane texture varies in a conformal manner. In the former case, [100] and [110] directions of grains preferentially align along the radial direction and the direction of platen rotation, respectively. In the latter case, the preferential orientation of grains in the radial direction becomes [112], while that in the direction of rotation remains to be [110]. The occurrence of the anisotropic stresses and their dependence on film thickness is related to the evolution of the anisotropic structure and in-plane texture. The correlation is discussed in terms of the modulus effect associated with in-plane texture, the stress relief at intercolumnar voids, and the texture transition. (C) 2002 American Institute of Physics. C1 Delphi Res Labs, Shelby Township, MI 48315 USA. Univ Michigan, Dept Mat Sci & Engn, Ctr Nanomat Sci, Ann Arbor, MI 48109 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Zhao, ZB (reprint author), Delphi Res Labs, 51786 Shelby Pkwy, Shelby Township, MI 48315 USA. NR 29 TC 19 Z9 19 U1 3 U2 13 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 DEC 15 PY 2002 VL 92 IS 12 BP 7183 EP 7192 DI 10.1063/1.1521791 PG 10 WC Physics, Applied SC Physics GA 619UD UT WOS:000179495100034 ER PT J AU Long, GJ Mahieu, B Sales, BC Hermann, RP Grandjean, F AF Long, GJ Mahieu, B Sales, BC Hermann, RP Grandjean, F TI Electronic structure of thallium filled skutterudites studied by x-ray absorption and Mossbauer spectroscopy SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TEMPERATURE TRANSPORT-PROPERTIES; P-TYPE COSB3; FIRST-PRINCIPLES; YBFE4SB12 AB Thallium L-III-edge x-ray absorption and iron-57 and tin-119 Mossbauer spectral measurements have been carried out to probe the electronic structure of the three sites in the filled skutterudite TlxCo4-yFeySb12 and TlxCo4Sb12-zSnz compounds with a range of x, y, and z values. The thallium L-III-edge x-ray absorption spectra are independent of x, y, and z and are well reproduced by full multiple scattering calculations with a cluster with a radius of 8.5 Angstrom centered on thallium. The iron-57 Mossbauer spectra consist of two doublets and the major component is assigned to iron on the cobalt sublattice in view of its hyperfine parameters. The origin of the minor component is uncertain and is tentatively assigned to either iron with thallium vacancies as next nearest neighbors or to iron in the voids. The tin-119 Mossbauer spectral hyperfine parameters clearly indicate that tin substitutes for antimony in the skutterudite structure. Further, the tin electronic configuration is very similar to that of antimony and is insensitive to the thallium content. (C) 2002 American Institute of Physics. C1 Univ Missouri, Dept Chem, Rolla, MO 65409 USA. Catholic Univ Louvain, CSTR, Dept Chem, B-1348 Louvain, Belgium. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Liege, Dept Phys, B-4000 Sart Tilman Par Liege, Belgium. RP Univ Missouri, Dept Chem, Rolla, MO 65409 USA. EM glong@umr.edu; fgrandjean@ulg.ac.be RI Hermann, Raphael/F-6257-2013 OI Hermann, Raphael/0000-0002-6138-5624 NR 31 TC 9 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 2002 VL 92 IS 12 BP 7236 EP 7241 DI 10.1063/1.1525069 PG 6 WC Physics, Applied SC Physics GA 619UD UT WOS:000179495100042 ER PT J AU Seager, CH Myers, SM Wright, AF Koleske, DD Allerman, AA AF Seager, CH Myers, SM Wright, AF Koleske, DD Allerman, AA TI Drift, diffusion, and trapping of hydrogen in p-type GaN SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TRANSITION-STATE THEORY; GALLIUM NITRIDE; ACCEPTORS; SILICON AB Using capacitance-voltage measurements we have measured both the diffusion and the field-induced drift of H in GaN p/n(+) diodes grown by metalorganic vapor phase epitaxy. Our data are well described by a computational model which simulates all of the important electronic processes as well as the drift, diffusion, and trapping of hydrogen in the GaN lattice. The experimental data demonstrate that H exists in the positive charge state; they also suggest that hydrogen diffusivity is anisotropic in this hexagonal material. In the temperature range from similar to200 to 310 degreesC we have determined that the sum of the activation energies for diffusion and binding of H+ to magnesium acceptors is 2.03 eV. This is similar to0.6 eV larger than previous density functional theory estimates of this quantity. We present first-principles calculations which demonstrate the observed diffusion anisotropy and which suggest possible reasons why previous treatments underestimate the barrier for hydrogen diffusive motion. (C) 2002 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 29 TC 40 Z9 40 U1 1 U2 18 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 2002 VL 92 IS 12 BP 7246 EP 7252 DI 10.1063/1.1520719 PG 7 WC Physics, Applied SC Physics GA 619UD UT WOS:000179495100044 ER PT J AU Yan, YF Al-Jassim, MM AF Yan, YF Al-Jassim, MM TI Carbon impurities in MgB2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SUPERCONDUCTING MGB2; ELECTRONIC-STRUCTURE; ART.; PSEUDOPOTENTIALS; TRANSITION; BORON AB The structural and electronic properties of carbon impurities in MgB2 are investigated by first-principles total-energy calculations. We find that high concentration of C impurities could be incorporated in MgB2 due to their low-formation energies. Substitutional C impurities have lower formation energies than interstitial C. Thus, the majority of C impurities in MgB2 should be substitutional, which results in a lattice parameter decrease in the a-b plane. C impurities are found to reduce the density of states of MgB2 around the Fermi energy, and therefore, may cause a decrease in critical temperature T-c. (C) 2002 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. EM yanfa_yan@nrel.gov NR 20 TC 15 Z9 15 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 2002 VL 92 IS 12 BP 7687 EP 7689 DI 10.1063/1.1524011 PG 3 WC Physics, Applied SC Physics GA 619UD UT WOS:000179495100120 ER PT J AU Peterson, KA Dunning, TH AF Peterson, KA Dunning, TH TI Accurate correlation consistent basis sets for molecular core-valence correlation effects: The second row atoms Al-Ar, and the first row atoms B-Ne revisited SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GAUSSIAN-BASIS SETS; POLARIZATION POTENTIALS; ALUMINUM; ENERGIES; BORON; N-2; SPECTROSCOPY; FREQUENCIES; ARGON; BCL AB Correlation consistent basis sets for accurately describing core-core and core-valence correlation effects in atoms and molecules have been developed for the second row atoms Al-Ar. Two different optimization strategies were investigated, which led to two families of core-valence basis sets when the optimized functions were added to the standard correlation consistent basis sets (cc-pVnZ). In the first case, the exponents of the augmenting primitive Gaussian functions were optimized with respect to the difference between all-electron and valence-electron correlated calculations, i.e., for the core-core plus core-valence correlation energy. This yielded the cc-pCVnZ family of basis sets, which are analogous to the sets developed previously for the first row atoms [D. E. Woon and T. H. Dunning, Jr., J. Chem. Phys. 103, 4572 (1995)]. Although the cc-pCVnZ sets exhibit systematic convergence to the all-electron correlation energy at the complete basis set limit, the intershell (core-valence) correlation energy converges more slowly than the intrashell (core-core) correlation energy. Since the effect of including the core electrons on the calculation of molecular properties tends to be dominated by core-valence correlation effects, a second scheme for determining the augmenting functions was investigated. In this approach, the exponents of the functions to be added to the cc-pVnZ sets were optimized with respect to just the core-valence (intershell) correlation energy, except that a small amount of core-core correlation energy was included in order to ensure systematic convergence to the complete basis set limit. These new sets, denoted weighted core-valence basis sets (cc-pwCVnZ), significantly improve the convergence of many molecular properties with n. Optimum cc-pwCVnZ sets for the first-row atoms were also developed and show similar advantages. Both the cc-pCVnZ and cc-pwCVnZ basis sets were benchmarked in coupled cluster [CCSD(T)] calculations on a series of second row homonuclear diatomic molecules (Al-2, Si-2, P-2, S-2, and Cl-2), as well as on selected diatomic molecules involving first row atoms (CO, SiO, PN, and BCl). For the calculation of core correlation effects on energetic and spectroscopic properties, the cc-pwCVnZ basis sets are recommended over the cc-pCVnZ ones. (C) 2002 American Institute of Physics. C1 Washington State Univ, Dept Chem, Pullman, WA 99164 USA. Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Tennessee, Oak Ridge Natl Lab, Joint Inst Computat Sci, Oak Ridge, TN 37831 USA. RP Peterson, KA (reprint author), Washington State Univ, Dept Chem, Pullman, WA 99164 USA. NR 29 TC 931 Z9 931 U1 4 U2 56 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 DEC 15 PY 2002 VL 117 IS 23 BP 10548 EP 10560 DI 10.1063/1.1520138 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 619UC UT WOS:000179495000015 ER PT J AU Lee, SJE Chakraborty, AK AF Lee, SJE Chakraborty, AK TI Sequence dependence of polymer dynamics in quenched disordered media: Weak attraction facilitates transport SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RANDOM HETEROPOLYMERS; STATISTICAL-MECHANICS; TRANSLOCATION; ADSORPTION; REPTATION; CHAIN; MODEL AB We study the dynamics of polymers in a random disordered medium of fixed obstacles using kinetic Monte Carlo methods. The polymers can have monomers which have attractive (A-type), repulsive (R-type) or neutral (H-type) interactions with the fixed obstacles that comprise the disordered medium. Several classes of homopolymers and heteropolymers with diverse sequences have been studied. Our most noteworthy result is that, above a threshold temperature, polymer bearing monomers that are attracted to the disordered medium translocate faster through the medium than those bearing neutral or repulsive monomers. We discuss how a delicate balance between energetic and entropic factors leads to this counterintuitive outcome. By examining heteropolymers with different sequences, we also find that the dependence of mobility on average composition is stronger than that on higher order correlations characterizing the sequence distribution. Connections between our results and experiments with synthetic and biological systems are noted. (C) 2002 American Institute of Physics. C1 Univ Calif Berkeley, Biophys Grad Grp, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Biophys Grad Grp, Berkeley, CA 94720 USA. NR 27 TC 5 Z9 5 U1 0 U2 1 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 DEC 15 PY 2002 VL 117 IS 23 BP 10869 EP 10876 DI 10.1063/1.1519838 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 619UC UT WOS:000179495000047 ER PT J AU Dessauer, HC Glenn, TC Densmore, LD AF Dessauer, HC Glenn, TC Densmore, LD TI Studies on the molecular evolution of the crocodylia: Footprints in the sands of time SO JOURNAL OF EXPERIMENTAL ZOOLOGY LA English DT Article; Proceedings Paper CT 2nd International Crocodilian DNA Workshop CY NOV, 2001 CL SAN DIEGO, CALIFORNIA ID ALLIGATOR-MISSISSIPPIENSIS; MITOCHONDRIAL GENOMES; AMERICAN ALLIGATOR; SEX DETERMINATION; ORDER CROCODILIA; TEMPERATURE; SYSTEMATICS; PHYLOGENY; PHYSIOLOGY; POPULATION AB A reasonably large number of studies focusing on the molecular evolution of crocodilians have been completed during the past 100 years. Proteins were initially studied before DNA was known to carry the genetic information of cells and organisms, and were subsequently studied to infer changes at the DNA level. More recently, studies on the DNA itself have been completed. We have had the pleasure of taking part in or facilitating many studies conducted over the past 50 years, especially several of the earliest studies done using newly developed molecular techniques. We provide a review of the molecular genetic studies on crocodilians, summarizing the findings of these studies as well as the context in which they were undertaken. This review is a personal look at the history of molecular studies on the evolutionary biology of crocodilians. Our excuse for this focus is that our professors, our students and we have had the opportunity to be among the first to apply many new techniques to studies of crocodilians since 1950, when one of us (HCD) was a graduate student of Roland Coulson and Tom Hernandez. Although we will review much of the material in this subject area, we do not claim that it is complete. Instead, we focus our presentation on work in which we have participated or with which we are particularly familiar. We especially focus on materials relevant to the research presented at the 2(nd) International Crocodilian DNA Workshop, 7-9 November, 2001, at the San Diego Zoo. Thus, the following review also stands as a tribute to our mentors, students, and colleagues. (C) 2002 Wiley-Liss, Inc. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ S Carolina, Dept Biol Sci, Columbia, SC 29208 USA. Louisiana State Univ, Hlth Sci Ctr, Dept Biochem & Mol Biol, New Orleans, LA 70119 USA. Texas Tech Univ, Dept Biol Sci, Lubbock, TX 79409 USA. RP Glenn, TC (reprint author), Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. RI Glenn, Travis/A-2390-2008 NR 81 TC 5 Z9 7 U1 0 U2 19 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0022-104X J9 J EXP ZOOL JI J. Exp. Zool. PD DEC 15 PY 2002 VL 294 IS 4 BP 302 EP 311 DI 10.1002/jez.10208 PG 10 WC Zoology SC Zoology GA 621JL UT WOS:000179585200002 PM 12461810 ER PT J AU Glenn, TC Staton, JL Vu, AT Davis, LM Bremer, JRA Rhodes, WE Brisbin, IL Sawyer, RH AF Glenn, TC Staton, JL Vu, AT Davis, LM Bremer, JRA Rhodes, WE Brisbin, IL Sawyer, RH TI Low mitochondrial DNA variation among American alligators and a novel non-coding region in crocodilians SO JOURNAL OF EXPERIMENTAL ZOOLOGY LA English DT Article; Proceedings Paper CT 2nd International Crocodilian DNA Workshop CY NOV, 2001 CL SAN DIEGO, CALIFORNIA ID POPULATION-GENETICS; NONEQUILIBRIUM MODELS; PHYLOGEOGRAPHY; SEQUENCES; TURTLE; CONSERVATION; GENOMES; VARIABILITY; BOTTLENECK; EVOLUTION AB We analyzed 1317-1823 base pairs (bp) of mitochondrial DNA sequence beginning in the 5' end of cytochrome b (cyt b) and ending in the central domain of the control region for 25 American alligators (Alligator mississippiensis) and compared these to a homologous sequence from a Chinese alligator (A. sinensis). Both species share a non-coding spacer between cyt b and tRNA(Thr). Chinese alligator cyt b differs from that of the American alligator by 17.5% at the nucleotide level and 13.8% for inferred amino acids, which is consistent with their presumed ancient divergence. Only two cyt b haplotypes were detected among the 25 American alligators (693-1199 by surveyed), with one haplotype shared among 24 individuals. One alligator from Mississippi differed from all other alligators by a single silent substitution. The control region contained only slightly more variation among the 25 American alligators, with two variable positions (624 by surveyed), yielding three haplotypes with 22, two, and one individuals in each of these groups. Previous genetic studies examining allozymes and the proportion of variable microsatellite DNA loci also found low levels of genetic diversity in American alligators. However, in contrast with allozymes, microsatellites, and morphology, the mtDNA data shows no evidence of differentiation among populations from the extremes of the species range. These results suggest that American alligators underwent a severe population bottleneck in the late Pleistocene, resulting in nearly homogenous mtDNA among all American alligators today. (C) 2002 Wiley-Liss, Inc. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ S Carolina, Dept Biol Sci, Columbia, SC 29208 USA. Univ S Carolina, Belle W Baruch Inst Marine & Coastal Res, Columbia, SC 29208 USA. S Carolina Dept Nat Resources, Dennis Wildlife Res Ctr, Bonneau, SC 29431 USA. RP Glenn, TC (reprint author), Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. RI Glenn, Travis/A-2390-2008 NR 74 TC 27 Z9 29 U1 1 U2 17 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0022-104X J9 J EXP ZOOL JI J. Exp. Zool. PD DEC 15 PY 2002 VL 294 IS 4 BP 312 EP 324 DI 10.1002/jez.10206 PG 13 WC Zoology SC Zoology GA 621JL UT WOS:000179585200003 PM 12461811 ER PT J AU Davis, LM Glenn, TC Strickland, DC Guillette, LJ Elsey, RM Rhodes, WE Dessauer, HC Sawyer, RH AF Davis, LM Glenn, TC Strickland, DC Guillette, LJ Elsey, RM Rhodes, WE Dessauer, HC Sawyer, RH TI Microsatellite DNA analyses support an east-west phylogeographic split of American alligator populations SO JOURNAL OF EXPERIMENTAL ZOOLOGY LA English DT Article; Proceedings Paper CT 2nd International Crocodilian DNA Workshop CY NOV, 2001 CL SAN DIEGO, CA ID JUVENILE ALLIGATORS; FLORIDA LAKES; FRESH-WATER; MISSISSIPPIENSIS; LOCI; RATTLESNAKE; PATERNITY; DISTANCES; MARKERS; TURTLES AB We examined the population genetic structure of American alligators (Alligator mississippiensis) sampled from 12 localities across the southeastern United States. The primary goal of this study was to determine the extent of population differentiation among alligators from four Florida lakes using eight microsatellite loci and compare the results to additional sites located at varying distances from them. Analyses of population structure revealed little differentiation (F-ST=0.039; Rho=0.012) among the four Florida lakes, Apopka, Griffin, Orange and Woodruff, which are all located in the St. John's River watershed in north-central Florida. Further, there was little differentiation among these samples and samples collected from the Everglades National Park (F-ST=0.044; Rho=0.009) and south Georgia (F-ST=0.045; Rho=0.032). Therefore, these six samples were pooled together as a "FL/sGA group." Similarly, samples collected in the western extent of the range, Anahuac National Wildlife Refuge in Texas and Salvador Wildlife Management Area, Marsh Island Wildlife Refuge and Rockefeller Wildlife Refuge in Louisiana, also lacked population structure (F-ST=0.024; R-ST=0.040). These four populations were pooled into the "TX/LA group." Comparisons of these two groups with samples taken from the Santee Coastal Reserve in South Carolina and Mobile, Alabama yielded three to four times more differentiation among groups (F-ST=0.131; Rho=0.187). These and other analyses support the hypothesis of an east-west phylogeographic split in American alligator populations and are consistent with studies of many freshwater fish and aquatic and terrestrial turtles distributed throughout this same geographic region. (C) 2002 Wiley-Liss, Inc. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ S Carolina, Dept Biol Sci, Columbia, SC 29208 USA. Univ Florida, Dept Zool, Gainesville, FL 32611 USA. Louisiana Dept Wildlife & Fisheries, Rockefeller Wildlife Refuge, Grand Chenier, LA 70643 USA. S Carolina Dept Nat Resources, Dennis Wildlife Res Ctr, Bonneau, SC 29431 USA. Louisiana State Univ, Med Ctr, Dept Biochem & Mol Biol, New Orleans, LA 70119 USA. RP Glenn, TC (reprint author), Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. EM Travis.Glenn@sc.edu RI Glenn, Travis/A-2390-2008 NR 59 TC 33 Z9 36 U1 1 U2 17 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0022-104X J9 J EXP ZOOL JI J. Exp. Zool. PD DEC 15 PY 2002 VL 294 IS 4 BP 352 EP 372 DI 10.1002/jez.10189 PG 21 WC Zoology SC Zoology GA 621JL UT WOS:000179585200007 PM 12461815 ER PT J AU Xu, K Wongpreedee, K Russell, AM AF Xu, K Wongpreedee, K Russell, AM TI Microstructure and strength of a deformation processed Al-20%Sn in situ composite SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID POWDER-METALLURGY; ALLOYS; TITANIUM; YTTRIUM AB An Al-20 vol% Sn metal-metal composite was deformation processed by extrusion, swaging, and wire drawing to a total true strain of 7.4, resulting in a microstructure with Sn filaments in an Al matrix. Both the size and spacing of the Sn filaments decreased as deformation processing progressed. The strength of these composites increased exponentially with the reduction in spacing of the Sn filaments. Immediately after deformation, the Sn second phase showed a convoluted, ribbon-shaped filamentary morphology, but the Sn filaments spheroidized during prolonged storage at room temperature. A thermodynamic assessment is presented for this spheroidization phenomenon. (C) 2002 Kluwer Academic Publishers. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Xu, K (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. OI Russell, Alan/0000-0001-5264-0104 NR 22 TC 4 Z9 5 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD DEC 15 PY 2002 VL 37 IS 24 BP 5209 EP 5214 DI 10.1023/A:1021092001147 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 615BV UT WOS:000179226700006 ER PT J AU Wilson, BK Hrma, P Alton, J Plaisted, TJ Vienna, JD AF Wilson, BK Hrma, P Alton, J Plaisted, TJ Vienna, JD TI The effect of composition on spinel equilibrium and crystal size in high-level waste glass SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB The equilibrium concentration (C-o) of spinel was measured in 16 high-level waste (HLW) glasses as a function of temperature (T). Glasses were formulated by increasing or decreasing concentrations of Al2O3, Cr2O3, Fe2O3, Li2O, MgO, Na2O, or NiO, one-at-a-time, from a baseline composition. Data were fitted using the quasi-ideal-solution relationship between C-o and T. The coefficients of this relationship were expressed as functions of glass composition using first-order approximation. All glass components had an effect on liquidus temperature (T-L), but only NiO and Fe2O3 had a significant impact on spinel concentration below T-L. The temperature at which Co had a given value was also expressed as a function of glass composition. These results can be used to optimize a HLW glass formulation to meet a constraint of either no spinel or a limited spinel fraction in the melter. In addition, the measurement of the size of spinel crystals and subsequent calculation of crystal number density (n) showed that Cr2O4 and Al2O3 increase n. (C) 2002 Kluwer Academic Publishers. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wilson, BK (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 11 TC 4 Z9 4 U1 1 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD DEC 15 PY 2002 VL 37 IS 24 BP 5327 EP 5331 DI 10.1023/A:1021081126162 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 615BV UT WOS:000179226700022 ER PT J AU McCleskey, TM Ehler, DS Young, JS Pesiri, DR Jarvinen, GD Sauer, NN AF McCleskey, TM Ehler, DS Young, JS Pesiri, DR Jarvinen, GD Sauer, NN TI Asymmetric membranes with modified gold films as selective gates for metal ion separations SO JOURNAL OF MEMBRANE SCIENCE LA English DT Article DE composite membranes; facilitated transport; inorganic membranes; liquid membranes; microporous; porous membranes ID SUPPORTED LIQUID MEMBRANES; POROUS ALUMINA MEMBRANES; FACILITATED TRANSPORT; CATION-TRANSPORT; GAS SEPARATION AB Thin layers of gold (700 A) were deposited on manufactured alumina pourous supports to yield nanopores with openings of <7 nm. A self-assembled monolayer (SAM) of alkyl thiols was then attached to provide a hydrophobic support for trialkyl phosphine oxide-based metal ion carriers. The resulting gated membranes provided a barrier to ions including H+, and Ca2+, NO3-, and CH3COO-. When an aqueous feed solution of 4.2 mM uranyl nitrate and I M lithium nitrate pH 4, and a receiving solution of I M sodium acetate pH 5.5 were used 100% of the metal was transported across the membrane by facilitated transport via the phosphate or phosphine oxide carrier. The thin gates transported metal ions as neutral nitrate complexes with fluxes high enough to be limited by the alumina support. The flux rates of 200,000 metal ions per pore per second are only a factor of 5 below that observed for the potassium channel. High selectivity of U over Eu is observed until the [U] is <0.84 mM in the feed solution, despite the fact the Eu actually transports faster when U is not present. This work demonstrates that selectivity can be added without impeding transport by using thin selective layers. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP McCleskey, TM (reprint author), Los Alamos Natl Lab, MS J514, Los Alamos, NM 87545 USA. RI McCleskey, Thomas/J-4772-2012; OI Mccleskey, Thomas/0000-0003-3750-3245 NR 24 TC 14 Z9 14 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0376-7388 J9 J MEMBRANE SCI JI J. Membr. Sci. PD DEC 15 PY 2002 VL 210 IS 2 BP 273 EP 278 AR PII S0376-7388(02)00387-3 DI 10.1016/S0376-7388(02)00387-3 PG 6 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA 620UY UT WOS:000179551900007 ER PT J AU Bansil, R Nie, HF Konak, C Helmstedt, M Lal, J AF Bansil, R Nie, HF Konak, C Helmstedt, M Lal, J TI Structure and dynamics of solutions of a polystyrene-polybutadiene pentablock copolymer in a styrene-selective solvent SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Physical-Society CY MAR, 2002 CL INDIANAPOLIS, INDIANA SP Amer Phys Soc, Div Polymer Phys DE dynamic light scattering; neutron scattering; block copolymers; solution properties; aggregation ID ABA BLOCK COPOLYMER; TRIBLOCK COPOLYMERS; LIGHT-SCATTERING; SEMIDILUTE SOLUTIONS; A-BLOCK; MULTIBLOCK COPOLYMERS; DIBLOCK COPOLYMERS; B-BLOCK; BEHAVIOR; DEPENDENCE AB We have examined solutions of a polystyrene-polybutadiene pentablock copolymer in 1,4-dioxane, a slightly selective solvent for polystyrene and a theta solvent for polybutadiene, with static light scattering (SLS), dynamic light scattering (DLS), and small-angle neutron scattering (SANS). The SANS data have been analyzed with the Percus-Yevick model to represent the scattering from interacting cores, approximated as hard spheres, and with a Lorentzian function to represent the scattering from unassociated and associated polymer chains. The SANS data at 25 degreesC clearly reveal interacting domains, approximately 6 nm in radius, formed by the association of the insoluble polybutadiene block in the 20% sample. The 4% sample does not show such domains, whereas the 7% sample represents an intermediate situation, with both unassociated polymer and associated polymer. At higher temperatures, the domains dissolve. The DLS data for samples with concentrations of 2-22% show two diffusive modes: a fast mode corresponding to the cooperative dynamics of concentration fluctuations and a slow mode corresponding to the diffusion of clusters. The large length-scale heterogeneities, indicated by the strong angular dependence of SLS, implies that the small microdomains of about 10-15 polybutadiene blocks are bridged by the polystyrene chains, forming large aggregates with randomly distributed crosslinks on length scales much larger than the domain size. (C) 2002 Wiley Periodicals, Inc. C1 Boston Univ, Ctr Polymer Studies, Boston, MA 02215 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Acad Sci Czech Republ, Inst Macromol Chem, Prague, Czech Republic. Univ Leipzig, Fak Phys & Geowissenschaften, D-04103 Leipzig, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. RP Bansil, R (reprint author), Boston Univ, Ctr Polymer Studies, Boston, MA 02215 USA. RI Konak, Cestmir/H-7177-2014 NR 36 TC 4 Z9 4 U1 0 U2 4 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 DEC 15 PY 2002 VL 40 IS 24 BP 2807 EP 2816 DI 10.1002/polb.10332 PG 10 WC Polymer Science SC Polymer Science GA 618WW UT WOS:000179441200007 ER PT J AU Fernandez-Gonzalez, R Jones, A Garcia-Rodriguez, E Chen, PY Idica, A Lockett, SJ Barcellos-Hoff, MH Ortiz-de-Solorzano, C AF Fernandez-Gonzalez, R Jones, A Garcia-Rodriguez, E Chen, PY Idica, A Lockett, SJ Barcellos-Hoff, MH Ortiz-de-Solorzano, C TI System for combined three-dimensional morphological and molecular analysis of thick tissue specimens SO MICROSCOPY RESEARCH AND TECHNIQUE LA English DT Article DE computer assisted microscopy; 3D reconstruction; assisted histopathology; JAVA ID NUCLEI; SEGMENTATION AB We present a new system for simultaneous morphological and molecular analysis of thick tissue samples. The system is composed of a computer-assisted microscope and a JAVA-based image display, analysis, and visualization program that allows acquisition, annotation, meaningful storage, three-dimensional reconstruction, and analysis of structures of interest in thick sectioned tissue specimens. We describe the system in detail and illustrate its use by imaging, reconstructing, and analyzing two complete tissue blocks that were differently processed and stained. One block was obtained from a ductal carcinoma in situ (DCIS) lumpectomy specimen and stained alternatively with Hematoxilyn and Eosin (H&E), and with a counterstain and fluorescence in situ hybridization (FISH) to the ERB-B2 gene. The second block contained a fully sectioned mammary gland of a mouse, stained for histology with H&E. We show how the system greatly reduces the amount of interaction required for the acquisition and analysis and is, therefore, suitable for studies that require morphologically driven, wide-scale (e.g., whole gland) analysis of complex tissue samples or cultures. Published 2002 Wiley-Liss, Inc.(dagger). C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Ortiz-de-Solorzano, C (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, 1 Cyclotron Rd, MS 84-171, Berkeley, CA 94720 USA. RI Ortiz de Solorzano, Carlos/G-3278-2010; Fernandez-Gonzalez, Rodrigo/F-6145-2012 OI Ortiz de Solorzano, Carlos/0000-0001-8720-0205; NR 9 TC 21 Z9 23 U1 0 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1059-910X J9 MICROSC RES TECHNIQ JI Microsc. Res. Tech. PD DEC 15 PY 2002 VL 59 IS 6 BP 522 EP 530 DI 10.1002/jemt.10233 PG 9 WC Anatomy & Morphology; Biology; Microscopy SC Anatomy & Morphology; Life Sciences & Biomedicine - Other Topics; Microscopy GA 629DF UT WOS:000180034600010 PM 12467029 ER PT J AU Naulleau, PP Sweatt, WC Tichenor, DA AF Naulleau, PP Sweatt, WC Tichenor, DA TI Theoretical efficiency analysis of a condenser-embedded grating-based spectral purity filter for EUV lithography SO OPTICS COMMUNICATIONS LA English DT Article DE extreme ultraviolet; lithography; monochromator; multilayer; grating ID EXTREME-ULTRAVIOLET LITHOGRAPHY; NM AB Being based on reflective optics, extreme ultraviolet (EUV) lithography systems are, in principle, relatively immune to chromatic errors. However, illumination bandwidth control is still required for EUV lithography. For example, appreciable amounts of UV power, combined with resist sensitivity to this wavelength band, would decrease image contrast. Also, appreciable amounts of IR power would place unacceptable thermal loads on the projection optics. A practical method for spectral filtering, widely used in short-wavelength synchrotron applications, is the grating monochromator. Here we present the theoretical performance analysis, of a,grating-based spectral purity filter integrated into an EUV lithography condenser system. Although the specific examples presented here are geared towards a specific condenser design, it should be noted that the methods described are generally applicable to a variety of condenser designs as might be found in future EUV lithography systems. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Naulleau, PP (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, 1 Cycltoron Rd, Berkeley, CA 94720 USA. NR 18 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD DEC 15 PY 2002 VL 214 IS 1-6 BP 31 EP 38 AR PII S0030-4018(02)02169-7 DI 10.1016/S0030-4018(02)02169-7 PG 8 WC Optics SC Optics GA 626QV UT WOS:000179885500005 ER PT J AU Dodin, IY Fisch, NJ AF Dodin, IY Fisch, NJ TI Dynamic volume holography and optical information processing by Raman scattering SO OPTICS COMMUNICATIONS LA English DT Article DE holography; Raman scattering; 3D pulses ID STORAGE; LIGHT AB A method of producing holograms of three-dimensional (3D) optical pulses is proposed. It is shown that both the amplitude and the phase profile of 3D optical pulse can be stored in dynamic perturbations of a Raman medium, such as plasma. By employing Raman scattering in a nonlinear medium, information carried by a laser pulse can be captured in the form of a slowly propagating low-frequency wave that persists for a time large compared with the pulse duration. If such a hologram is then probed with a short laser pulse, the information stored in the medium can be retrieved in a second scattered electromagnetic wave. The recording and retrieving processes can conserve robustly the pulse shape, thus enabling the recording and retrieving with fidelity of information stored in optical signals. While storing or reading the pulse structure, the optical information can be processed as an analog or digital signal, which allows simultaneous transformation of 3D continuous images or computing discrete arrays of binary data. By adjusting the phase fronts of the reference pulses, one can also perform focusing, redirecting, and other types of transformation of the output pulses. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Princeton Univ, Princeton Plasma Phys Lab, Dept Astrophys Sci, Princeton, NJ 08543 USA. RP Dodin, IY (reprint author), Princeton Univ, Princeton Plasma Phys Lab, Dept Astrophys Sci, POB 451, Princeton, NJ 08543 USA. EM idodin@pppl.gov NR 20 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 EI 1873-0310 J9 OPT COMMUN JI Opt. Commun. PD DEC 15 PY 2002 VL 214 IS 1-6 BP 83 EP 98 AR PII S0030-4018(02)02144-2 DI 10.1016/S0030-4018(02)02144-2 PG 16 WC Optics SC Optics GA 626QV UT WOS:000179885500011 ER PT J AU Taubman, MS Myers, TL Cannon, BD Williams, RM Capasso, F Gmachl, C Sivco, DL Cho, AY AF Taubman, MS Myers, TL Cannon, BD Williams, RM Capasso, F Gmachl, C Sivco, DL Cho, AY TI Frequency stabilization of quantum-cascade lasers by use of optical cavities SO OPTICS LETTERS LA English DT Article ID DISTRIBUTED-FEEDBACK LASERS; ABSORPTION-SPECTROSCOPY; SEMICONDUCTOR-LASERS; LINEWIDTH; NOISE; BAND AB We report a heterodyne beat with a linewidth of 5.6 +/- 0.6 Hz between two cavity-stabilized quantum-cascade lasers operating at 8.5 mum. We also present a technique for measuring this beat that avoids the need for extreme isolation of the optical cavities from the environment, that of employing a third servo loop with low bandwidth to force one cavity to track the slow drifts and low-frequency fluctuations of the other. Although it is not fully independent, this technique greatly facilitates heterodyne beat measurements for evaluating the performance of cavity-locked lasers above the bandwidth of the third loop. (C) 2002 Optical Society of America. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. RP Taubman, MS (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 22 TC 41 Z9 41 U1 0 U2 10 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 DEC 15 PY 2002 VL 27 IS 24 BP 2164 EP 2166 DI 10.1364/OL.27.002164 PG 3 WC Optics SC Optics GA 625AR UT WOS:000179795000006 PM 18033470 ER PT J AU Moeser, J Gabitov, I Jones, CKRT AF Moeser, J Gabitov, I Jones, CKRT TI Pulse stabilization by high-order dispersion management SO OPTICS LETTERS LA English DT Article ID 3RD-ORDER DISPERSION; SOLITON PROPAGATION; TRANSMISSION; SYSTEMS; FIBER AB The stabilizing effects of dispersion management (DM) at second and third order are studied for both single-channel and wavelength-division multiplexed (WDM) systems. We first derive a model for the slow evolution of a pulse in an optical fiber with high-order dispersion management (HODM). For single-channel systems, in contrast with conventional DM with constant third-order dispersion, this equation possesses a stable solution, the ground state for its associated Hamiltonian, which propagates nearly periodically under direct numerical simulation. Improved performance for WDM systems is also observed, as complicated pulse interactions, which can lead to undesirable effects such as frequency shift, are prevented by HODM. (C) 2002 Optical Society of America. C1 Univ Colorado, Boulder, CO 80309 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ N Carolina, Chapel Hill, NC 27599 USA. RP Moeser, J (reprint author), Univ Colorado, Boulder, CO 80309 USA. NR 16 TC 5 Z9 5 U1 0 U2 0 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 DEC 15 PY 2002 VL 27 IS 24 BP 2206 EP 2208 DI 10.1364/OL.27.002206 PG 3 WC Optics SC Optics GA 625AR UT WOS:000179795000020 PM 18033484 ER PT J AU Windt, DL Gullikson, EM Walton, CC AF Windt, DL Gullikson, EM Walton, CC TI Normal-incidence reflectance of optimized W/B4C x-ray multilayers in the range 1.4 nm < lambda < 2.4 nm SO OPTICS LETTERS LA English DT Article AB We have fabricated W/B4C multilayers having periods in the range d = 0.8-1.2 run and measured their soft-x-ray performance near normal incidence in the wavelength range 1.4 < lambda < 2.4 nm. By adjusting the fractional layer thickness of W we have produced structures having interface widths sigma similar to 0.29 nm (i.e., as determined from normal-incidence reflectometry), thus having optimal soft-x-ray performance. We describe our results and discuss their implications, particularly with regard to the development of short-wavelength normal-incidence x-ray optics. (C) 2002 Optical Society of America. C1 Columbia Astrophys Lab, New York, NY 10027 USA. Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Windt, DL (reprint author), Columbia Astrophys Lab, 550 W 120th St, New York, NY 10027 USA. NR 10 TC 20 Z9 22 U1 0 U2 3 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 DEC 15 PY 2002 VL 27 IS 24 BP 2212 EP 2214 DI 10.1364/OL.27.002212 PG 3 WC Optics SC Optics GA 625AR UT WOS:000179795000022 PM 18033486 ER PT J AU Lorenz, B Lenzi, J Cmaidalka, J Meng, RL Sun, YY Xue, YY Chu, CW AF Lorenz, B Lenzi, J Cmaidalka, J Meng, RL Sun, YY Xue, YY Chu, CW TI Superconductivity in the C32 intermetallic compounds AAl(2-x)Si(x),with A = Ca and Sr, and 0.6 < x < 1.2 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article DE CaAlSi; SrAlSi; BaAlSi; superconductivity; Seebeck coefficient ID MGB2 AB The intermetallic compounds AAl(2-x)Si(x), where A = Ca, Sr or Ba, crystallize in the C32 structure, same as the recently discovered MgB2 with a high superconducting transition temperature of 39 K. For x = 1, superconductivity has been observed in AAlSi with A = Ca and Sr, but not with A = Ba. The transition temperatures are 7.8 and 5.1 K, respectively for CaAlSi and SrAlSi. The CaAl2-xSix compound system display a T-c-peak at x = 1, a possible x-induced electronic transition at x similar to 0.75 and a possible miscibility gap near x similar to 1.1 which results in a very broad superconducting transition. The Seebeck coefficients of AAlSi indicate that their carriers are predominantly electrons in nature, in contrast to the holes in MgB2. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Houston, Texas Ctr Supercond, Houston, TX 77204 USA. Univ Houston, Dept Phys, Houston, TX 77204 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Hong Kong Univ Sci & Technol, Hong Kong, Hong Kong, Peoples R China. RP Univ Houston, Texas Ctr Supercond, Houston, TX 77204 USA. EM blorenz@uh.edu NR 10 TC 67 Z9 68 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD DEC 15 PY 2002 VL 383 IS 3 BP 191 EP 196 AR PII S0921-4534(02)02056-7 DI 10.1016/S0921-4534(02)02056-7 PG 6 WC Physics, Applied SC Physics GA 617LK UT WOS:000179363000001 ER PT J AU Je, JH You, H Cullen, WG Maroni, VA Ma, B Koritala, RE Thieme, C AF Je, JH You, H Cullen, WG Maroni, VA Ma, B Koritala, RE Thieme, C TI Detection of a Pd-Ni interlayer at the Pd/Ni interface of an epitaxial Pd film on cube textured nickel (001) SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article DE Pd/Ni; buffer layer; biaxial texture; cube-textured Ni substrates ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; COATED CONDUCTORS; BUFFER LAYERS; GROWTH; EVAPORATION; DEPOSITION; OXIDE AB We studied the microstructure of a Pd overlayer deposited on a cube textured Ni(0 0 1) substrate using synchrotron X-ray scattering. We find the existence of an epitaxial Pd-Ni interlayer between the epitaxial Pd layer and the Ni substrate. The Pd-Ni interlayer, which is compressively strained in a manner similar to the Pd overlayer, seemingly acts to relieve the strain at the Pd/Ni interface caused by the Pd-Ni lattice mismatch. The Ni mosaic distribution of our samples is multiply spiked with a rocking angle spread of similar to16degrees, which reconciles the previously reported observation of saw tooth peaks on top of a Gaussian distribution for a similarly prepared I'd on Ni specimen. The observed sharpening of the mosaic distributions for the Pd(0 0 2) grains (full-width at half-maximum (FWHM) = 1.95degrees) and for the (0 0 2) grains of Pd-Ni interlayer (FWHM = 3.0degrees) indicates that the Pd and Pd-Ni(0 0 2) layers conform to the surface morphology instead of to the (0 0 1) crystallographic planes of Ni-substrate grains. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. POSTECH, Dept Mat Sci & Engn, Pohang 790784, South Korea. Amer Supercond, Westborough, MA 01581 USA. RP Je, JH (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Koritala, Rachel/F-1774-2011; Ma, Beihai/I-1674-2013; You, Hoydoo/A-6201-2011 OI Ma, Beihai/0000-0003-3557-2773; You, Hoydoo/0000-0003-2996-9483 NR 13 TC 3 Z9 3 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD DEC 15 PY 2002 VL 383 IS 3 BP 241 EP 246 AR PII S0921-4534(02)01325-4 DI 10.1016/S0921-4534(02)01325-4 PG 6 WC Physics, Applied SC Physics GA 617LK UT WOS:000179363000008 ER PT J AU Batzill, M Katsiev, K Gaspar, DJ Diebold, U AF Batzill, M Katsiev, K Gaspar, DJ Diebold, U TI Variations of the local electronic surface properties of TiO2(110) induced by intrinsic and extrinsic defects SO PHYSICAL REVIEW B LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; NB-DOPED TIO2; RESONANT PHOTOEMISSION; OXIDE SURFACES; GAP STATES; OXYGEN; RUTILE; STM; VISUALIZATION; SPECTROSCOPY AB Variation of the local electronic structure at rutile TiO2(110) surfaces was studied by scanning tunneling spectroscopy (STS). Structural surface features such as step edges, (1x2) reconstructed strands, and their terminations were correlated to changes in tunneling spectra. In particular, band-gap states, associated with a reduced surface, showed characteristic variations. In addition, electronic variations due to extrinsic defects are discussed. Nanometer wide protrusions in constant current scanning tunneling microscopy images were identified in STS as local electronic alterations. These features are interpreted to be due to local band bending induced by individual, charged impurity atoms. C1 Tulane Univ, Dept Phys, New Orleans, LA 70118 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Tulane Univ, Dept Phys, New Orleans, LA 70118 USA. EM diebold@tulane.edu RI Diebold, Ulrike/A-3681-2010; Gaspar, Dan/H-6166-2011; Batzill, Matthias/J-4297-2014; OI Diebold, Ulrike/0000-0003-0319-5256; Batzill, Matthias/0000-0001-8984-8427; Gaspar, Daniel/0000-0002-8089-810X NR 61 TC 52 Z9 52 U1 5 U2 49 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 DEC 15 PY 2002 VL 66 IS 23 AR 235401 DI 10.1103/PhysRevB.66.235401 PG 10 WC Physics, Condensed Matter SC Physics GA 633JL UT WOS:000180279400092 ER PT J AU Bronold, FX Martin, I Saxena, A Smith, DL AF Bronold, FX Martin, I Saxena, A Smith, DL TI Magnetic-field dependence of electron spin relaxation in n-type semiconductors SO PHYSICAL REVIEW B LA English DT Article ID GAAS; ANISOTROPY AB We present a theoretical investigation of the magnetic-field dependence of the longitudinal (T-1) and transverse (T-2) spin-relaxation times of conduction-band electrons in n-type III-V semiconductors. We find that the interplay between the Dyakonov-Perel process and an additional spin-relaxation channel, which originates from the electron wave-vector dependence of the electron g factor, yields a maximal T-2 at a finite magnetic field. We compare our results with existing experimental data on n-type GaAs and make specific additional predictions for the magnetic-field dependence of electron-spin lifetimes. C1 Ernst Moritz Arndt Univ Greifswald, Inst Phys, D-17487 Greifswald, Germany. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Ernst Moritz Arndt Univ Greifswald, Inst Phys, D-17487 Greifswald, Germany. NR 18 TC 47 Z9 48 U1 0 U2 8 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 DEC 15 PY 2002 VL 66 IS 23 AR 233206 DI 10.1103/PhysRevB.66.233206 PG 4 WC Physics, Condensed Matter SC Physics GA 633JL UT WOS:000180279400013 ER PT J AU Evans, JW Bartelt, MC AF Evans, JW Bartelt, MC TI Island sizes and capture zone areas in submonolayer deposition: Scaling and factorization of the joint probability distribution SO PHYSICAL REVIEW B LA English DT Article ID THIN-FILM GROWTH; EPITAXIAL-GROWTH; ADATOM CAPTURE; NUCLEATION; AGGREGATION AB The joint probability distribution (JPD) for island sizes, s, and capture zone areas, A, provides extensive information on the distribution of islands formed during submonolayer deposition. For irreversible island formation via homogeneous nucleation, this JPD is shown to display scaling of the type F(s/s(av),A/A(av)), where "av" denotes average values. The form of F reflects both a broad monomodal distribution of island sizes, and a significant spread of capture zone areas for each island size. A key ingredient determining this scaling behavior is the impact of each nucleation event on existing capture zone areas, which we quantify by kinetic Monte Carlo simulations. Combining this characterization of the spatial aspects of nucleation with a simplified but realistic factorization ansatz for the JPD, we provide a concise rate equation formulation for the variation of both the capture zone area and the island density with island size. This is achieved by analysis of the first two moments of the evolution equations for the JPD. C1 Iowa State Univ, Dept Math, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. RP Evans, JW (reprint author), Iowa State Univ, Dept Math, Ames, IA 50011 USA. NR 25 TC 45 Z9 46 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 DEC 15 PY 2002 VL 66 IS 23 AR 235410 DI 10.1103/PhysRevB.66.235410 PG 12 WC Physics, Condensed Matter SC Physics GA 633JL UT WOS:000180279400101 ER PT J AU Gilbert, B Frazer, BH Zhang, H Huang, F Banfield, JF Haskel, D Lang, JC Srajer, G De Stasio, G AF Gilbert, B Frazer, BH Zhang, H Huang, F Banfield, JF Haskel, D Lang, JC Srajer, G De Stasio, G TI X-ray absorption spectroscopy of the cubic and hexagonal polytypes of zinc sulfide SO PHYSICAL REVIEW B LA English DT Article ID NEAR-EDGE STRUCTURE; ELECTRONIC-STRUCTURE; FINE-STRUCTURE; K-EDGE; ZNS; SEMICONDUCTORS; NANOCRYSTALS; SIZE; CDS; DENSITIES AB We investigate the sensitivity of x-ray absorption spectroscopy to cubic-hexagonal polytypism in which nearest-neighbor positions are virtually unchanged. Experimental spectra and multiple-scattering calculations are reported at the major absorption edges in the zinc-blende and wurtzite modifications of ZnS. We demonstrate that d-like unoccupied bands are preferentially affected, as only L-edge absorption is sensitive to this structural transition. The results allow near-edge x-ray absorption spectroscopy to be evaluated as a detection method for crystal structure modifications in nano-scale systems. C1 Univ Wisconsin, Dept Phys, Stoughton, WI 53589 USA. Univ Wisconsin, Ctr Synchrotron Radiat, Stoughton, WI 53589 USA. Ecole Polytech Fed Lausanne, Inst Phys Appl, CH-1015 Lausanne, Switzerland. Univ Wisconsin, Dept Geol & Geophys, Madison, WI 53706 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Gilbert, B (reprint author), Univ Calif Berkeley, Dept Earth & Planetary Sci, 455 McCone Hall, Berkeley, CA 94720 USA. RI Gilbert, Benjamin/E-3182-2010; Gilbert, Pupa/A-6299-2010 OI Gilbert, Pupa/0000-0002-0139-2099 NR 32 TC 61 Z9 63 U1 1 U2 28 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 DEC 15 PY 2002 VL 66 IS 24 AR 245205 DI 10.1103/PhysRevB.66.245205 PG 6 WC Physics, Condensed Matter SC Physics GA 634BB UT WOS:000180319200034 ER PT J AU Ismail Hofmann, P Baddorf, AP Plummer, EW AF Ismail Hofmann, P Baddorf, AP Plummer, EW TI Thermal expansion at a metal surface: A study of Mg(0001) and Be(10(1)over-bar0) SO PHYSICAL REVIEW B LA English DT Article ID ENERGY ION-SCATTERING; AL(110) SURFACE; TEMPERATURE-DEPENDENCE; MULTILAYER RELAXATION; LATTICE-RELAXATION; CONTRACTION; LEED; NI(110); PHONONS; AG(111) AB Quantitative low-energy electron diffraction current-voltage measurements have been utilized to determine the thermal expansion of the Mg(0001) and Be(10 (1) over bar0) surfaces. The close-packed Mg(0001) surface exhibits a small thermal expansion while the more open Be(10 (1) over bar0) surface has a dramatic thermal contraction in the first interlayer spacing, accompanied by an expansion in the second interlayer spacing. A comparison of this data with all other measurements of the low-temperature thermal expansion reveals a quite striking difference for open surfaces of different metals. Significant negative thermal contraction at the surface occurs only on open faces of light mass metals. A simple force constant model indicates that this behavior correlates with the ratio of thermal motion parallel and perpendicular to the surface. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Aarhus, Inst Storage Ring Facilities, DK-8000 Aarhus C, Denmark. RP Ismail (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RI Hofmann, Philip/B-5938-2008; Baddorf, Arthur/I-1308-2016 OI Hofmann, Philip/0000-0002-7367-5821; Baddorf, Arthur/0000-0001-7023-2382 NR 50 TC 3 Z9 4 U1 1 U2 6 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 DEC 15 PY 2002 VL 66 IS 24 AR 245414 DI 10.1103/PhysRevB.66.245414 PG 9 WC Physics, Condensed Matter SC Physics GA 634BB UT WOS:000180319200073 ER PT J AU Lee, TL Kumpf, C Kazimirov, A Lyman, PF Scherb, G Bedzyk, MJ Nielsen, M Feidenhans'l, R Johnson, RL Fimland, BO Zegenhagen, J AF Lee, TL Kumpf, C Kazimirov, A Lyman, PF Scherb, G Bedzyk, MJ Nielsen, M Feidenhans'l, R Johnson, RL Fimland, BO Zegenhagen, J TI Structural analysis of the indium-stabilized GaAs(001)-c(8x2) surface SO PHYSICAL REVIEW B LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; MOLECULAR-BEAM EPITAXY; QUANTUM-WELLS; 001 SURFACES; INAS; GROWTH; GAAS; RECONSTRUCTION; HETEROSTRUCTURES; (001)-SURFACES AB The indium-stabilized GaAs(001)-c(8x2) surface was investigated by surface x-ray diffraction and x-ray standing waves. We find that the reconstruction closely resembles the c(8x2) structure described by the recently proposed unified model for clean III-V semiconductor surfaces [Kumpf , Phys. Rev. Lett. 86, 3586 (2001)]. Consistent with this unified model, no In dimers are found for the present surface. Instead, for coverages less than 0.25 monolayers, the In adatoms adsorb at the initially unoccupied hollow sites to form In rows along the [110] direction. Between the In rows, surface and subsurface Ga dimers are found to coexist in the trench areas. Above 0.25 monolayers, the additional In adatoms fill the trenches and replace the surface Ga atoms. The final structure of the surface layer is essentially identical to the InAs clean surface, except that the In heights are substantially different due to the lateral strain induced by the lattice mismatch. This structural difference explains why the ladder-type pattern observed previously by scanning tunneling microscopy only appears for the In/GaAs(001) and InAs/GaAs(001) surfaces, but not for the InAs clean surface. The structural model we propose for the In-stabilized GaAs(001)-c(8x2) surface, which fully agrees with the scanning tunneling microscopy results, should therefore generally apply to strained InAs(001) surfaces. C1 Northwestern Univ, Dept Mat Sci, Evanston, IL 60208 USA. Northwestern Univ, Mat Res Ctr, Evanston, IL 60208 USA. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Univ Wurzburg, D-97074 Wurzburg, Germany. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Riso Natl Lab, Condensed Matter Phys & Chem Dept, DK-4000 Roskilde, Denmark. Univ Hamburg, Inst Expt Phys 2, D-22761 Hamburg, Germany. Norwegian Univ Sci & Technol, N-7491 Trondheim, Norway. European Synchrotron Radiat Facil, F-38043 Grenoble, France. RP Lee, TL (reprint author), Northwestern Univ, Dept Mat Sci, Evanston, IL 60208 USA. RI Bedzyk, Michael/B-7503-2009; Kumpf, Christian/K-3624-2013; Bedzyk, Michael/K-6903-2013 OI Kumpf, Christian/0000-0003-3567-5377; NR 28 TC 8 Z9 8 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 2002 VL 66 IS 23 AR 235301 DI 10.1103/PhysRevB.66.235301 PG 9 WC Physics, Condensed Matter SC Physics GA 633JL UT WOS:000180279400068 ER PT J AU Lei, C Bauer, M Read, K Tobey, R Liu, Y Popmintchev, T Murnane, MM Kapteyn, HC AF Lei, C Bauer, M Read, K Tobey, R Liu, Y Popmintchev, T Murnane, MM Kapteyn, HC TI Hot-electron-driven charge transfer processes on O-2/Pt(111) surface probed by ultrafast extreme-ultraviolet pulses SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-OXYGEN; METAL-SURFACES; LASER-PULSES; PT(111); FEMTOSECOND; SPECTROSCOPY; DESORPTION; ADSORPTION; O-2; CO AB We use ultrafast extreme-ultraviolet photoelectron spectroscopy to directly monitor the electron dynamics and the characteristic valence-band photoelectron spectra associated with a hot-electron mediated surface chemical reaction. By adsorbing molecular oxygen onto a Pt(111) surface and exciting it with an ultrafast laser pulse, charge transfer induced changes in the platinum-oxygen bond were observed on femtosecond time scales. By simultaneously monitoring both the hot-electron distribution at the Fermi edge and the valence-band photoemission spectra, it was determined that the thermalization of the hot-electron gas precedes significant changes in the O-2/Pt bond. C1 Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Kaiserslautern, Fachbereich Phys, D-67663 Kaiserslautern, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RP Lei, C (reprint author), Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RI Popmintchev, Tenio/B-6715-2008; Kapteyn, Henry/H-6559-2011; Bauer, Michael/G-5111-2016 OI Popmintchev, Tenio/0000-0002-2023-2226; Kapteyn, Henry/0000-0001-8386-6317; Bauer, Michael/0000-0002-4391-9899 NR 45 TC 25 Z9 25 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 2002 VL 66 IS 24 AR 245420 DI 10.1103/PhysRevB.66.245420 PG 10 WC Physics, Condensed Matter SC Physics GA 634BB UT WOS:000180319200079 ER PT J AU Li, ZY AF Li, ZY TI Modified thermal radiation in three-dimensional photonic crystals SO PHYSICAL REVIEW B LA English DT Article ID SPONTANEOUS EMISSION AB Thermal radiation from an empty blackbody cavity follows the conventional Wien's displacement law. At a temperature T=2500 K, the maximum monochromatic radiation intensity lies at a wavelength of 1.16 mum, and radiation into the visible band occupies only 3% of the total radiation energy. In this paper, we show that when the cavity is filled with a three-dimensional photonic crystal, a strong thermal radiation band can appear in the visible regime, significantly improving the luminescence efficiency. This is attributed to the redistribution of photon density of states (DOS) in different frequency ranges in the photonic crystal leading to orders-of-magnitude enhancement of DOS in the visible wavelength over that in the infrared wavelengths. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Li, ZY (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 8 TC 19 Z9 19 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 2002 VL 66 IS 24 AR 241103 DI 10.1103/PhysRevB.66.241103 PG 4 WC Physics, Condensed Matter SC Physics GA 634BB UT WOS:000180319200003 ER PT J AU List, EJW Scherf, U Mullen, K Graupner, W Kim, CH Shinar, J AF List, EJW Scherf, U Mullen, K Graupner, W Kim, CH Shinar, J TI Direct evidence for singlet-triplet exciton annihilation in pi-conjugated polymers SO PHYSICAL REVIEW B LA English DT Article ID LIGHT-EMITTING-DIODES; POLY(PARA-PHENYLENE)-TYPE LADDER POLYMERS; DETECTED MAGNETIC-RESONANCE; ENERGY-TRANSFER; SPECTROSCOPY; POLARONS; GAP; ELECTROLUMINESCENCE; PHOTOLUMINESCENCE; PHOSPHORESCENCE AB A blend of two conjugated polymers with different optical band gaps and different triplet exciton (TE) magnetic resonance features was studied by means of photoinduced absorption (PA) and photoluminescence detected magnetic resonance. From the latter we find that a reduction of TE's on either of the two polymers enhances the radiative singlet exciton (SE) decay on both polymers nearly identically. The PA results rule out other possible mechanisms to yield this signal, except one: a long-range SE-TE annihilation due to a dipole-dipole transfer mechanism. Based on this finding, we calculate the transfer radius and quantify the annihilation process for this system and for other conjugated polymers. C1 Graz Univ Technol, Inst Solid State Phys, Christian Doppler Lab Adv Funct Mat, A-8010 Graz, Austria. Inst Nanostruct Mat & Photon, A-8160 Weiz, Austria. Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. Univ Potsdam, Inst Phys & Theoret Chem, D-14476 Golm, Germany. Max Planck Inst Polymer Res, Mainz, Germany. Virginia Tech, Dept Phys, Blacksburg, VA 24060 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP List, EJW (reprint author), Graz Univ Technol, Inst Solid State Phys, Christian Doppler Lab Adv Funct Mat, A-8010 Graz, Austria. RI Scherf, Ullrich/G-1552-2012; List-Kratochvil, Emil/M-5312-2013 NR 32 TC 33 Z9 33 U1 1 U2 9 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 2002 VL 66 IS 23 AR 235203 DI 10.1103/PhysRevB.66.235203 PG 5 WC Physics, Condensed Matter SC Physics GA 633JL UT WOS:000180279400059 ER PT J AU Miyake, T Aryasetiawan, F Kotani, T van Schilfgaarde, M Usuda, M Terakura, K AF Miyake, T Aryasetiawan, F Kotani, T van Schilfgaarde, M Usuda, M Terakura, K TI Total energy of solids: An exchange and random-phase approximation correlation study SO PHYSICAL REVIEW B LA English DT Article ID GENERALIZED GRADIENT APPROXIMATION; DER-WAALS FORCES; DENSITY-FUNCTIONAL THEORY; BODY PERTURBATION-THEORY; ELECTRON-GAS; SELF-ENERGY; BAND-GAPS; SEMICONDUCTORS; INSULATORS AB Total energies of solids are calculated by an ab initio method based on the Green's-function theory. Green's function is constructed from one-body wave functions and eigenvalues obtained in the local-density approximation (LDA) to density-functional theory, and the correlation energy is estimated within the random-phase approximation. The scheme is applied to Na and Si. In both cases, the equilibrium lattice constants are in reasonable agreement with experiments. The role of the exchange-correlation energy in the total-energy curve is discussed in detail in comparison with the LDA. C1 Tokyo Inst Technol, Dept Phys, Meguro Ku, Tokyo 1528551, Japan. AIST, Res Inst Computat Sci, Tsukuba Cent 2, Tsukuba, Ibaraki 3058568, Japan. Osaka Univ, Dept Phys, Toyonaka, Osaka 5600043, Japan. Sandia Natl Labs, Livermore, CA 94551 USA. Tokyo Univ Sci, Fac Sci & Technol, Dept Phys, Noda, Chiba 2788510, Japan. RP Tokyo Inst Technol, Dept Phys, Meguro Ku, 2-12-1 Oh Okayama, Tokyo 1528551, Japan. RI kotani, takao/G-4355-2011 OI kotani, takao/0000-0003-1693-7052 NR 42 TC 61 Z9 61 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 2002 VL 66 IS 24 AR 245103 DI 10.1103/PhysRevB.66.245103 PG 4 WC Physics, Condensed Matter SC Physics GA 634BB UT WOS:000180319200022 ER PT J AU Paggel, JJ Wei, CM Chou, MY Luh, DA Miller, T Chiang, TC AF Paggel, JJ Wei, CM Chou, MY Luh, DA Miller, T Chiang, TC TI Atomic-layer-resolved quantum oscillations in the work function: Theory and experiment for Ag/Fe(100) SO PHYSICAL REVIEW B LA English DT Article ID THIN METAL-FILMS; BAND-STRUCTURE; CRYSTALLINE; WELLS; AG AB The work function of atomically uniform Ag films grown on Fe(100) is measured as a function of film thickness. It shows layer-resolved variations as a result of quantum confinement of the valence electrons. A first-principles calculation reproduces the observed variations except for very thin films (one and two monolayers), and the differences can be attributed, in part, to strain effects caused by the lattice mismatch between Ag and Fe. These results illustrate the close interaction between interface effects and surface properties. C1 Free Univ Berlin, Inst Expt Phys, D-14195 Berlin, Germany. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Frederick Seitz Mat Res Lab, Urbana, IL 61801 USA. RP Paggel, JJ (reprint author), Free Univ Berlin, Inst Expt Phys, D-14195 Berlin, Germany. RI LUH, DAH-AN/B-3921-2008; Chiang, Tai/H-5528-2011; Wei, Ching-Ming/F-7931-2012; Chou, Mei-Yin/D-3898-2012 NR 20 TC 63 Z9 63 U1 1 U2 12 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 DEC 15 PY 2002 VL 66 IS 23 AR 233403 DI 10.1103/PhysRevB.66.233403 PG 4 WC Physics, Condensed Matter SC Physics GA 633JL UT WOS:000180279400030 ER PT J AU Pomeroy, JM Jacobsen, J Hill, CC Cooper, BH Sethna, JP AF Pomeroy, JM Jacobsen, J Hill, CC Cooper, BH Sethna, JP TI Kinetic Monte Carlo-molecular dynamics investigations of hyperthermal copper deposition on Cu(111) SO PHYSICAL REVIEW B LA English DT Article ID BEAM-ASSISTED DEPOSITION; THIN-FILMS; INTRINSIC STRESS; ION; NUCLEATION; PT(111); GROWTH; MORPHOLOGY; SIMULATION AB Detailed kinetic Monte Carlo-molecular dynamics (KMC-MD) simulations of hyperthermal energy (10-100 eV) copper homoepitaxy reveal a reentrant layer-by-layer growth mode at low temperatures (50 K) and reasonable fluxes (1 ML/s. where ML stands for monolayer). This growth mode is the result of atoms with hyperthermal kinetic energies becoming inserted into islands when the impact site is near a step edge. The yield for atomic insertion as calculated with molecular dynamics near (111) step edges reaches a maximum near 18 eV. KMC-MD simulations of growing films find a minimum in the rms roughness as a function of energy near 25 eV. We find that the rms roughness saturates just beyond 0.5 ML of coverage in films grown with energies greater than 25 eV due to the onset of adatom-vacancy formation near 20 eV. Adatom-vacancy pairs increase the island nuclei density and the step-edge density, which increase the number of sites available to insert atoms. Smoothest growth in this regime is achieved by maximizing island and step-edge densities, which consequently reverses the traditional roles of temperature and flux: low temperatures and high fluxes produce the smoothest surfaces in these films. Dramatic increases in island densities are found to persist at room temperature, where island densities increase an order of magnitude from 20 to 150 eV. C1 Cornell Univ, Cornell Ctr Mat Res, Ithaca, NY 14853 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Haldor Topsoe Res Labs, DK-2800 Lyngby, Denmark. Gene Network Sci, Ithaca, NY 14850 USA. RP Pomeroy, JM (reprint author), Cornell Univ, Cornell Ctr Mat Res, Ithaca, NY 14853 USA. NR 31 TC 56 Z9 56 U1 1 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 2002 VL 66 IS 23 AR 235412 DI 10.1103/PhysRevB.66.235412 PG 8 WC Physics, Condensed Matter SC Physics GA 633JL UT WOS:000180279400103 ER PT J AU Wu, YZ Won, CY Rotenberg, E Zhao, HW Toyoma, F Smith, NV Qiu, ZQ AF Wu, YZ Won, CY Rotenberg, E Zhao, HW Toyoma, F Smith, NV Qiu, ZQ TI Dispersion of quantum well states in Cu/Co/Cu(001) SO PHYSICAL REVIEW B LA English DT Article ID BAND-STRUCTURE; PHOTOEMISSION; COPPER; SYSTEM; FILMS; OVERLAYERS; AG AB Quantum well states (QWS's) in Cu thin films grown on Co/Cu(001) were studied using angle-resolved photoemission spectroscopy. For the normal photoemission, QWS's from both lower and higher energy bands relative to the vacuum level were measured, and explained by phase accumulation method. QWS's from the lower band were studied in detail as a function of the in-plane momentum k(parallel to). We found that the QWS dispersion depends on the Cu film thickness. From the experimental data, we deduced the quantized perpendicular momentum k(perpendicular to) and the energy as a function of k(parallel to). Our results show that the in-plane effective mass can not be obtained by a simple parabolic fitting of the E vs k(parallel to) due to the dependence of k(perpendicular to) on k(parallel to). C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Chinese Acad Sci, Inst Phys, Int Ctr Quantum Struct, Beijing 100080, Peoples R China. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Wu, YZ (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Rotenberg, Eli/B-3700-2009; wu, YiZheng/O-1547-2013; Wu, yizheng/P-2395-2014; Qiu, Zi Qiang/O-4421-2016 OI Rotenberg, Eli/0000-0002-3979-8844; Wu, yizheng/0000-0002-9289-1271; Qiu, Zi Qiang/0000-0003-0680-0714 NR 20 TC 24 Z9 24 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 DEC 15 PY 2002 VL 66 IS 24 AR 245418 DI 10.1103/PhysRevB.66.245418 PG 5 WC Physics, Condensed Matter SC Physics GA 634BB UT WOS:000180319200077 ER PT J AU Abrams, D Akerib, DS Armel-Funkhouser, MS Baudis, L Bauer, DA Bolozdynya, A Brink, PL Bunker, R Cabrera, B Caldwell, DO Castle, JP Chang, CL Clarke, RM Crisler, MB Dixon, R Driscoll, D Eichblatt, S Gaitskell, RJ Golwala, SR Haller, EE Hellmig, J Holmgren, D Huber, ME Kamat, S Lu, A Mandic, V Martinis, JM Meunier, P Nam, SW Nelson, H Perera, TA Isaac, MCP Rau, W Ross, RR Saab, T Sadoulet, B Sander, J Schnee, RW Shutt, T Smith, A Sonnenschein, AH Spadafora, AL Wang, G Yellin, S Young, BA AF Abrams, D Akerib, DS Armel-Funkhouser, MS Baudis, L Bauer, DA Bolozdynya, A Brink, PL Bunker, R Cabrera, B Caldwell, DO Castle, JP Chang, CL Clarke, RM Crisler, MB Dixon, R Driscoll, D Eichblatt, S Gaitskell, RJ Golwala, SR Haller, EE Hellmig, J Holmgren, D Huber, ME Kamat, S Lu, A Mandic, V Martinis, JM Meunier, P Nam, SW Nelson, H Perera, TA Isaac, MCP Rau, W Ross, RR Saab, T Sadoulet, B Sander, J Schnee, RW Shutt, T Smith, A Sonnenschein, AH Spadafora, AL Wang, G Yellin, S Young, BA CA CDMS Collaboration TI Exclusion limits on the WIMP-nucleon cross section from the cryogenic dark matter search SO PHYSICAL REVIEW D LA English DT Article ID LOW-RADIOACTIVITY; PHONON PRODUCTION; 25 MK; IONIZATION; DETECTOR; GERMANIUM; VOLTAGE; CRYSTAL AB The Cryogenic Dark Matter Search (CDMS) employs low-temperature Ge and Si detectors to search for weakly interacting massive particles (WIMPs) via their elastic-scattering interactions with nuclei while discriminating against interactions of background particles. For recoil energies above 10 keV, events due to background photons are rejected with >99.9% efficiency, and surface events are rejected with >95% efficiency. The estimate of the background due to neutrons is based primarily on the observation of multiple-scatter events that should all be neutrons. Data selection is determined primarily by examining calibration data and vetoed events. Resulting efficiencies should be accurate to similar to10%. Results of CDMS data from 1998 and 1999 with a relaxed fiducial-volume cut (resulting in 15.8 kg days exposure on Ge) are consistent with an earlier analysis with a more restrictive fiducial-volume cut. Twenty-three WIMP candidate events are observed, but these events are consistent with a background from neutrons in all ways tested. Resulting limits on the spin-independent WIMP-nucleon elastic-scattering cross section exclude unexplored parameter space for WIMPs with masses between 10-70 GeV/c(2). These limits border, but do not exclude, parameter space allowed by supersymmetry models and accelerator constraints. Results are compatible with some regions reported as allowed at 3sigma by the annual-modulation measurement of the DAMA Collaboration. However, under the assumptions of standard WIMP interactions and a standard halo, the results are incompatible with the DAMA most likely value at >99.9% confidence level (C.L.), and are incompatible with the model-independent annual-modulation signal of DAMA at 99.99% C.L. in the asymptotic limit. C1 Case Western Reserve Univ, Dept Phys, Cleveland, OH 44106 USA. Brown Univ, Dept Phys, Providence, RI 02912 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Santa Clara Univ, Dept Phys, Santa Clara, CA 95053 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Univ Colorado, Dept Phys, Denver, CO 80217 USA. RP Schnee, RW (reprint author), Case Western Reserve Univ, Dept Phys, Cleveland, OH 44106 USA. RI Huber, Martin/B-3354-2011; OI Holmgren, Donald/0000-0001-6701-7737; Baudis, Laura/0000-0003-4710-1768 NR 74 TC 98 Z9 99 U1 1 U2 4 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 DEC 15 PY 2002 VL 66 IS 12 AR 122003 DI 10.1103/PhysRevD.66.122003 PG 35 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 634AL UT WOS:000180317800006 ER PT J AU Albuquerque, IFM Lamoureux, J Smoot, GF AF Albuquerque, IFM Lamoureux, J Smoot, GF TI Neutrino telescopes' sensitivity to dark matter SO PHYSICAL REVIEW D LA English DT Article ID MASSIVE PARTICLES; OSCILLATIONS; ENERGIES; LIMITS; EARTH; SUN AB The nature of the dark matter of the Universe is yet unknown and most likely is connected with new physics. The search for its composition is underway through direct and indirect detection. Fundamental physical aspects such as energy threshold, geometry and location are taken into account to investigate proposed neutrino telescopes of km(3) volume sensitivities to dark matter. These sensitivities are just sufficient to test a few weakly interacting massive particle scenarios. Telescopes of km(3) volume, such as IceCube, can definitely discover or exclude superheavy (M>10(10) GeV) strong interacting massive particles (simpzillas). Smaller neutrino telescopes such as ANTARES, AMANDA-II and NESTOR can probe a large region of simpzilla parameter space. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. EM IFAlbuquerque@lbl.gov; JILamoureux@lbl.gov; GFSmoot@lbl.gov RI Albuquerque, Ivone/H-4645-2012 OI Albuquerque, Ivone/0000-0001-7328-0136 NR 46 TC 4 Z9 4 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 2002 VL 66 IS 12 AR 125006 DI 10.1103/PhysRevD.66.125006 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 634AL UT WOS:000180317800055 ER PT J AU Kallosh, R Linde, A Prokushkin, S Shmakova, M AF Kallosh, R Linde, A Prokushkin, S Shmakova, M TI Supergravity, dark energy, and the fate of the universe SO PHYSICAL REVIEW D LA English DT Article ID HIGH-REDSHIFT SUPERNOVAE; COSMOLOGICAL CONSTANT; SUPERSYMMETRY BREAKING; ENTROPY CRISIS; SCALAR FIELD; QUINTESSENCE; MODELS; POTENTIALS; MANIFOLDS; GAUGINGS AB We propose a description of dark energy and acceleration of the universe in extended supergravities with de Sitter (dS) solutions. Some of them are related to M theory with noncompact internal spaces. Masses of ultralight scalars in these models are quantized in units of the Hubble constant: m(2)=nH(2). If the dS solution corresponds to a minimum of the effective potential, the universe eventually becomes dS space. If the dS solution corresponds to a maximum or a saddle point, which is the case in all known models based on N=8 supergravity, the flat universe eventually stops accelerating and collapses to a singularity. We show that in these models, as well as in the simplest models of dark energy based on N=1 supergravity, the typical time remaining before the global collapse is comparable to the present age of the universe, t=O(10(10)) yr. We discuss the possibility of distinguishing between various models and finding our destiny using cosmological observations. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Stanford Univ, Dept Phys, Stanford, CA 94305 USA. NR 67 TC 66 Z9 67 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 DEC 15 PY 2002 VL 66 IS 12 AR 123503 DI 10.1103/PhysRevD.66.123503 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 634AL UT WOS:000180317800016 ER PT J AU Kaloper, N Kleban, M Lawrence, A Shenker, S AF Kaloper, N Kleban, M Lawrence, A Shenker, S TI Signatures of short distance physics in the cosmic microwave background SO PHYSICAL REVIEW D LA English DT Article ID 11-DIMENSIONAL SUPERGRAVITY; INFLATIONARY PERTURBATIONS; SUBMILLIMETER DIMENSIONS; DENSITY PERTURBATIONS; SUPERSTRING MODELS; NATURAL INFLATION; QUANTUM-GRAVITY; STRING DUALITY; 11 DIMENSIONS; ONE-LOOP AB We systematically investigate the effect of short distance physics on the spectrum of temperature anisotropies in the cosmic microwave background produced during inflation. We present a general argument-assuming only low-energy locality-that the size of such effects is of order H-2/M-2, where H is the Hubble parameter during inflation and M is the scale of the high-energy physics. We evaluate the strength of such effects in a number of specific string and M theory models. In weakly coupled field theory and string theory models, the effects are far too small to be observed. In phenomenologically attractive Horava-Witten compactifications, the effects are much larger but still unobservable. In certain M theory models, for which the fundamental Planck scale is several orders of magnitude below the conventional scale of grand unification, the effects may be on the threshold of detectability. However, observations of both the scalar and tensor fluctuation contributions to the cosmic microwave background power spectrum-with a precision near the cosmic variance limit-are necessary in order to demonstrate unambiguously the existence of these signatures of high-energy physics. This is a formidable experimental challenge. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. SLAC Theory Grp, Menlo Pk, CA 94025 USA. RP Kaloper, N (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. OI Kleban, Matthew/0000-0002-1889-2487; Lawrence, Albion/0000-0003-4116-045X NR 78 TC 147 Z9 147 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 2002 VL 66 IS 12 AR 123510 DI 10.1103/PhysRevD.66.123510 PG 21 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 634AL UT WOS:000180317800023 ER PT J AU Gardner, EL Schiffer, WK Horan, BA Highfield, D Dewey, SL Brodie, JD Ashby, CR AF Gardner, EL Schiffer, WK Horan, BA Highfield, D Dewey, SL Brodie, JD Ashby, CR TI Gamma-vinyl GABA, an irreversible inhibitor of GABA transaminase, alters the acquisition and expression of cocaine-induced sensitization in male rats SO SYNAPSE LA English DT Article DE gamma-vinyl GABA; cocaine; sensitization; locomotion; stereotypy ID VENTRAL TEGMENTAL AREA; EXCITATORY AMINO-ACIDS; 5-HT3 RECEPTOR ANTAGONIST; MEDIAL PREFRONTAL CORTEX; BEHAVIORAL SENSITIZATION; BRAIN GABA; NUCLEUS-ACCUMBENS; 4-AMINO-HEX-5-ENOIC ACID; B RECEPTORS; DOPAMINE AB We examined the effect of (+/-)-gamma-vinyl GABA (GVG, Vigabatrin), an irreversible inhibitor of the enzyme GABA transaminase, on the acquisition and expression of cocaine-induced sensitization in albino male Sprague-Dawley rats. Animals received a single injection of 1 ml/kg i.p. of 0.9% saline or 15 mg/kg i.p. of (-)-cocaine and locomotor activity was assessed using automated locomotor cages and stereotyped behaviors were scored using a 4-point rating scale (Day 1). Subsequently, animals were given 15 mg/kg i.p. of cocaine every 48 h in their home cage for 1 week (Days 3, 5, and 7) and then given no treatment for 1 week. A challenge injection of 15 mg/kg i.p. of cocaine, but not vehicle, produced a significant increase in locomotor activity and stereotyped behaviors on Day 15 compared to animals that received cocaine on Day 1. Administration of 75 mg/kg i.p. of GVG 2.5 h before the cocaine injections did not significantly alter the acquisition of cocaine-induced locomotor sensitization. However, 150 mg/kg i.p. of GVG significantly attenuated the acquisition of cocaine-induced locomotor sensitization. Administration of 150 mg/kg i.p. of GVG 2.5 h before the cocaine challenge injection on Day 15 significantly attenuated the expression of cocaine-induced locomotor sensitization. Acquisition and expression of cocaine-induced sensitization of stereotypy was also significantly attenuated by 150 mg/kg i.p. of GVG. Since sensitization may be one of the factors involved in relapse to drug use, the present results, in combination with previous findings that GVG blocks the rewarding and incentive motivating effects of cocaine, suggest that GVG might prove useful in the treatment of cocaine addiction. (C) 2002 Wiley-Liss, Inc. C1 St Johns Univ, Coll Pharm & Allied Hlth Profess, Dept Pharmaceut Hlth Sci, Jamaica, NY 11439 USA. NIDA, Intramural Res Program, NIH, Baltimore, MD 21224 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NYU, Sch Med, Dept Psychiat, New York, NY 10016 USA. RP Ashby, CR (reprint author), St Johns Univ, Coll Pharm & Allied Hlth Profess, Dept Pharmaceut Hlth Sci, 8000 Utopia Pkwy, Jamaica, NY 11439 USA. OI Brodie, Jonathan/0000-0002-2254-8654 NR 77 TC 27 Z9 28 U1 0 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-4476 J9 SYNAPSE JI Synapse PD DEC 15 PY 2002 VL 46 IS 4 BP 240 EP 250 DI 10.1002/syn.10138 PG 11 WC Neurosciences SC Neurosciences & Neurology GA 608GQ UT WOS:000178838200004 PM 12373739 ER PT J AU Kleinman, LI Daum, PH Lee, YN Nunnermacker, LJ Springston, SR Weinstein-Lloyd, J Rudolph, J AF Kleinman, LI Daum, PH Lee, YN Nunnermacker, LJ Springston, SR Weinstein-Lloyd, J Rudolph, J TI Ozone production efficiency in an urban area SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE ozone production efficiency; urban plume; urban photochemistry; photochemistry; Phoenix ID POWER-PLANT PLUMES; ATMOSPHERIC CHEMISTRY; NITROGEN-OXIDES; UNITED-STATES; RURAL SITE; HYDROCARBONS; TROPOSPHERE; TENNESSEE; NASHVILLE; PHOTOOXIDATION AB [1] Ozone production efficiency can be defined as the number of molecules of oxidant (O-3 +NO2) produced photochemically when a molecule of NOx (NO +NO2) is oxidized. It conveys information about the conditions under which O-3 is formed and is an important parameter to consider when evaluating impacts from NOx emission sources. We present calculational and observational results on ozone production efficiency based on measurements made from aircraft flights in the Phoenix metropolitan area in May and June of 1998. Constrained steady state box model calculations are used to relate a ratio of O-3 production rate to NOx consumption rate (i.e., P(O-3)/ P(NOz)) to a VOC to NO2 ratio of OH reactivity. Lagrangian calculations show how this ratio generally increases with time due to oxidation chemistry and plume dilution. City to city differences in ozone production efficiency can be attributed to corresponding differences in VOC to NO2 reactivity ratio which in turn reflect emission patterns. Ozone production efficiencies derived from aircraft measurements in 20 plumes show a dependence on NOx concentration similar to that calculated for P(O-3)/ P(NOz). Calculations are based on data from a single location but are believed to be applicable to a wide range of plumes from different areas. C1 Brookhaven Natl Lab, Div Atmospher Sci, Upton, NY 11973 USA. SUNY Coll Old Westbury, Dept Chem Phys, Old Westbury, NY 11568 USA. York Univ, Dept Chem, Toronto, ON M3J 1P3, Canada. York Univ, Ctr Atmospher Res, Toronto, ON M3J 1P3, Canada. RP Kleinman, LI (reprint author), Brookhaven Natl Lab, Div Atmospher Sci, Upton, NY 11973 USA. EM kleinman@bnl.gov; phdaum@bnl.gov; ynlee@bnl.gov; lindan@bnl.gov; srs@bnl.gov; jlloyd@bnl.gov; rudolphj@yorku.ca NR 43 TC 43 Z9 47 U1 4 U2 27 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 14 PY 2002 VL 107 IS D23 AR 4733 DI 10.1029/2002JD002529 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 648UN UT WOS:000181169100013 ER PT J AU Turcotte, S Wimmer-Schweingruber, RF AF Turcotte, S Wimmer-Schweingruber, RF TI Possible in situ tests of the evolution of elemental and isotopic abundances in the solar convection zone SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article DE helioseismology; abundances; solar wind; fractionation; isotopic ratios; Sun ID SYSTEM ABUNDANCES; LITHIUM DEPLETION; LUNAR REGOLITH; CORONAL HOLE; WIND; FRACTIONATION; MODELS; CONSTRAINTS; METEORITES; DIFFUSION AB Helioseismology has shown that the chemical composition of the Sun has changed over its lifetime. The surface abundance of helium and heavy elements is believed to have decreased by up to 10% in relation to their initial values. However, this reduction is too small to be tested by direct observations of the photospheric chemical composition. Here we compare the predicted variations in the solar photospheric composition with precise measurements of abundances in meteorites and the solar wind composition. Although elemental composition ratios can vary by roughly a percent (e.g., for Ca/Mg and Ca/Fe) over the Sun's lifetime, their measurements are rife with uncertainties related to uncertainties in the interpretation of meteoritic measurements, photospheric determinations, and the complex fractionation processes occurring between the upper photosphere and lower chromosphere and the corona. On the other hand, isotopic ratios can be measured much more accurately and are not expected to be affected as much by extrasolar processes, although more work is required to quantify their effect. As the isotopic ratios evolve in the Sun proportionally to the mass ratios of the isotopes, light elements yield the highest variations in isotopic ratios. They are predicted to reach as high as 0.6% for O-18/O-16 and are only slightly lower in the cases of Mg-26/Mg-24 and Si-30/Si-28. Such a value should be well within the sensitivity of new missions such as Genesis. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Bern, Inst Phys, CH-3012 Bern, Switzerland. RP Lawrence Livermore Natl Lab, L-413,POB 808, Livermore, CA 94551 USA. EM sturcotte@igpp.ucllnl.org; robert.wimmer@phim.unibe.ch NR 57 TC 22 Z9 22 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 14 PY 2002 VL 107 IS A12 AR 1442 DI 10.1029/2002JA009418 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 649AU UT WOS:000181185400002 ER PT J AU Knapp, A Walter, M Weber, T Landers, AL Schossler, S Jahnke, T Schoffler, M Nickles, J Kammer, S Jagutzki, O Schmidt, LPH Osipov, T Rosch, J Prior, MH Schmidt-Bocking, H Cocke, CL Feagin, J Dorner, R AF Knapp, A Walter, M Weber, T Landers, AL Schossler, S Jahnke, T Schoffler, M Nickles, J Kammer, S Jagutzki, O Schmidt, LPH Osipov, T Rosch, J Prior, MH Schmidt-Bocking, H Cocke, CL Feagin, J Dorner, R TI Energy sharing and asymmetry parameters for photo double ionization of helium 100 eV above threshold in single-particle and Jacobi coordinates SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID DIFFERENTIAL CROSS-SECTIONS; DOUBLE PHOTOIONIZATION; ANGULAR-DISTRIBUTIONS; RECOIL-ION AB We present a joint experimental and theoretical study of the double differential cross section for the double ionization of helium by absorption of one 179 eV linear polarized photon (100 eV above threshold). We show the energy sharing and the asymmetry parameters in both single-particle coordinates and in Jacobi coordinates. An asymmetric sharing of the electron excess energy and a breakup of the electron pair preferentially parallel to the polarization axis is found. This marks a deviation from the propensity rule favouring perpendicular relative electron motion which has been observed to hold at energies closer to the double-ionization threshold. C1 Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. Univ Freiburg, Fak Phys, D-7800 Freiburg, Germany. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Calif State Univ Fullerton, Dept Phys, Fullerton, CA 92834 USA. RP Knapp, A (reprint author), Univ Frankfurt, Inst Kernphys, August Euler Str 6, D-60486 Frankfurt, Germany. RI Schoeffler, Markus/B-6261-2008; Walter, Michael/D-7984-2011; Doerner, Reinhard/A-5340-2008; Landers, Allen/C-1213-2013; Weber, Thorsten/K-2586-2013 OI Schoeffler, Markus/0000-0001-9214-6848; Walter, Michael/0000-0001-6679-2491; Doerner, Reinhard/0000-0002-3728-4268; Weber, Thorsten/0000-0003-3756-2704 NR 20 TC 25 Z9 25 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD DEC 14 PY 2002 VL 35 IS 23 BP L521 EP L526 AR PII S0953-4075(02)53345-9 DI 10.1088/0953-4075/35/23/103 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 635CT UT WOS:000180381000003 ER PT J AU Wei, CF Kotamarthi, VR Ogunsola, OJ Horowitz, LW Walters, S Wuebbles, DJ Avery, MA Blake, DR Browell, EV Sachse, GW AF Wei, CF Kotamarthi, VR Ogunsola, OJ Horowitz, LW Walters, S Wuebbles, DJ Avery, MA Blake, DR Browell, EV Sachse, GW TI Seasonal variability of ozone mixing ratios and budgets in the tropical southern Pacific: A GCTM perspective SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CHEMICAL-TRANSPORT MODEL; PEM-WEST-A; NONMETHANE HYDROCARBONS; EXPLORATORY MISSION; NORTH PACIFIC; CLIMATE-MODEL; PARAMETERIZATION; DISTRIBUTIONS; MOZART AB Significant seasonal variations in the concentrations of several trace gases were observed in the southern tropical Pacific during the Pacific Exploratory Mission (PEM) TROPICS-A (PT-A, September/October 1996) and PEM TROPICS-B (PT-B, March/April 1999) campaigns. The objective of this study is to evaluate the relationship between the measured and modeled seasonal variabilities through comparisons of these observations with model calculations. A three-dimensional (3-D) global-scale chemical transport model was employed to (1) evaluate the seasonal variations in ozone and CO mixing ratios; (2) calculate an ozone budget and identify its controlling factors; (3) evaluate the effectiveness of atmospheric transport barriers in the model, such as the Intertropical Convergence Zone (ITCZ); and (4) test the sensitivity of ozone over the tropical south Pacific to biomass-burning emissions. The model reproduces the main features of the observed seasonal variation in ozone and CO. According to the model calculation, the ozone burden during the PT-A was larger due to the transport of ozone into the central pacific middle troposphere from the west, whereas a net outflow of ozone from this region to the east resulted in a reduction of ozone burden during the PT-B period. Transport of ozone from the Northern Hemisphere into this region was found to be much larger during the PT-B period compared with the PT-A period. The in situ production and loss of ozone calculated in the model agreed with that derived from measurements. The gradients in the model for selected trace gases across the ITCZ were shown to be qualitatively similar to measurements. C1 Univ Illinois, Dept Atmospher Sci, Urbana, IL 61801 USA. Argonne Natl Lab, Argonne, IL 60439 USA. GFDL, Princeton, NJ USA. NCAR, Boulder, CO USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. Univ Calif Irvine, Irvine, CA USA. RP Wei, CF (reprint author), Univ Illinois, Dept Atmospher Sci, 105 S Gregory Ave, Urbana, IL 61801 USA. EM vrkotamarthi@anl.gov RI Horowitz, Larry/D-8048-2014 OI Horowitz, Larry/0000-0002-5886-3314 NR 40 TC 1 Z9 1 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 13 PY 2002 VL 108 IS D2 AR 8235 DI 10.1029/2001JD00772 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 648VG UT WOS:000181171000001 ER PT J AU Lawrence, DJ Feldman, WC Elphic, RC Little, RC Prettyman, TH Maurice, S Lucey, PG Binder, AB AF Lawrence, DJ Feldman, WC Elphic, RC Little, RC Prettyman, TH Maurice, S Lucey, PG Binder, AB TI Iron abundances on the lunar surface as measured by the Lunar Prospector gamma-ray and neutron spectrometers SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article DE Moon; iron abundances; gamma-ray spectroscopy; neutron spectroscopy; composition ID POLE AITKEN-BASIN; EPITHERMAL NEUTRONS; THORIUM ABUNDANCES; CLEMENTINE DATA; MOON; TIO2; FEO; MINERALOGY; IMAGES; FLUXES AB Global measurements of iron abundances on the lunar surface are presented using data from the Lunar Prospector (LP) Gamma-Ray Spectrometer (GRS) and Neutron Spectrometer (NS). In this study, we derive relative iron abundances from the low-altitude, high spatial resolution (similar to(45 km)(2)) LP data using the 7.6 MeV neutron capture gamma-ray doublet. As part of the LP-GRS analysis, we demonstrate the importance of accounting for variations in neutron number density across the lunar surface by measuring neutron fluxes using LP-NS data. In a first step of comparing the LP-GRS data with previously published iron abundances inferred from Clementine Spectral Reflectance (CSR) data, we show that the existing CSR FeO data are nonlinear with respect to the LP relative iron abundances. We use the LP data to linearize the relationship between the CSR and the relative iron values then recalibrate the CSR data to iron abundance using returned soil abundances. We then correlate the CSR data, except for major anomalies, with the LP relative iron measurements to convert the LP data to absolute iron abundances. When we compare the LP-GRS and revised CSR data sets, we find a very good correspondence. There are two locations (Mare Tranquillitatis and South Pole-Aitken (SPA) basin) that show major discrepancies, suggesting that the CSR data are locally overestimating iron abundances. In both these regions, the discrepancies identified by the LP-GRS/CSR comparison are possibly explained by mineralogical differences that are not accounted for in the CSR to FeO calibration. In regards to our understanding of the Moon, the LP data have found the following: (1) There exist large expanses of mare basalt in the western mare regions that have very high iron abundances (22-23 wt.% FeO) that are underrepresented but not absent from the returned sample collection and are highly unusual for mare soils, which typically contain a significant amount of highlands contamination. (2) The low iron abundances in the lunar highlands (similar to5 FeO wt.%) are consistent with a previous analysis using thermal and epithermal neutrons and with the idea that the lunar crust formed by a relatively simple magma ocean process. (3) The comparison of LP and CSR derived iron abundances suggests that the material within SPA basin is similar to a norite-type rock without an enriched mantle FeO signature. (4) A comparison of LP and CSR data at Tycho Crater shows a large discrepancy such that the CSR data show moderate iron abundances of 89 wt.% FeO while the LP data show very low iron abundances of 3-4 wt.% FeO. This discrepancy cannot yet be easily explained by any known process. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Observ Midi Pyrenees, F-31400 Toulouse, France. Univ Hawaii, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. Lunar Res Inst, Tucson, AZ 85747 USA. RP Lawrence, DJ (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Lawrence, David/E-7463-2015 OI Lawrence, David/0000-0002-7696-6667 NR 74 TC 118 Z9 122 U1 2 U2 8 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 DEC 13 PY 2002 VL 107 IS E12 AR 5130 DI 10.1029/2001JE001530 PG 26 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 648WP UT WOS:000181174200001 ER PT J AU Huttunen, KEJ Koskinen, HEJ Pulkkinen, TI Pulkkinen, A Palmroth, M Reeves, EGD Singer, HJ AF Huttunen, KEJ Koskinen, HEJ Pulkkinen, TI Pulkkinen, A Palmroth, M Reeves, EGD Singer, HJ TI April 2000 magnetic storm: Solar wind driver and magnetospheric response SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ELEMENTARY CURRENT SYSTEMS; CORONAL MASS EJECTIONS; INTERPLANETARY SHOCKS; GEOMAGNETIC STORMS; DISTURBANCES; ASSOCIATION; SUBSTORMS; DST; INJECTIONS; ORIGIN AB [1] On 4 April 2000, a coronal mass ejection (CME) took place close to the western limb of the Sun. The shock front of the CME hit the Earth's magnetosphere on 6 April. A strong interplanetary southward B-Z event in the sheath region caused a magnetic storm that was the second strongest in the year 2000 if quantified by the peak of the Dst index. We have analyzed this sequence of events using observations of several spacecraft in the solar wind and at geostationary orbit as well as recordings from more than 80 magnetometer stations at latitudes higher than 40 degreesN. In the sheath region behind the shock, the interplanetary magnetic field had an intense and long-sustained southward magnetic field orientation, and the solar wind magnetic pressure was very large, which compressed the dayside magnetopause inside geostationary orbit for a period of more than 6 hours. We conclude that it was the fluctuating but strongly southward field accompanied by the high pressure that allowed for the exceptionally strong driving of magnetospheric activity. During the main phase of the storm, the magnetosphere and ionosphere were in highly perturbed states, with several activations all around the auroral region. Detailed analysis shows that many of these activations were not substorms, in the sense that they were not associated with poleward and westward electrojet/auroral enhancement or geostationary particle injections, but were directly driven perturbations due to variations in the solar wind features. In fact, it was found that the development of the entire storm was quite independent of substorm activations and injections. Instead, the ring current development was driven by the strong convection enhancements. During the storm, the geomagnetically induced currents were strongly enhanced during several periods. While some activations were associated with substorm onsets or electrojet enhancements, others were caused by extremely localized and short-lived electrojet activations. C1 Univ Helsinki, Dept Phys Sci, Div Theoret Phys, FIN-00014 Helsinki, Finland. Finnish Meteorol Inst, FIN-00101 Helsinki, Finland. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NOAA, Space Environm Ctr, Boulder, CO 80303 USA. RP Huttunen, KEJ (reprint author), Univ Helsinki, Dept Phys Sci, Div Theoret Phys, POB 64, FIN-00014 Helsinki, Finland. RI Kilpua, Emilia/G-8994-2012; Reeves, Geoffrey/E-8101-2011; Pulkkinen, Tuija/D-8403-2012; Koskinen, Hannu/B-4971-2017 OI Reeves, Geoffrey/0000-0002-7985-8098; Pulkkinen, Tuija/0000-0002-6317-381X; Koskinen, Hannu/0000-0003-3839-6461 NR 44 TC 27 Z9 27 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 13 PY 2002 VL 107 IS A12 AR 1440 DI 10.1029/2001JA009154 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 649AP UT WOS:000181185000001 ER PT J AU Pawley, NH Koide, S Nicholson, LK AF Pawley, NH Koide, S Nicholson, LK TI Backbone dynamics and thermodynamics of Borrelia outer surface protein A SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE NMR; anisotropy; chemical exchange; dynamics; thermodynamics ID LAYER BETA-SHEET; ANISOTROPIC ROTATIONAL DIFFUSION; CC-CHEMOKINE EOTAXIN; BURGDORFERI OSPA; NMR-SPECTROSCOPY; CHEMICAL-EXCHANGE; TEMPERATURE-DEPENDENCE; IXODES-SCAPULARIS; HYDROPHOBIC CORE; SPIN RELAXATION AB Nuclear spin relaxation experiments performed at 298 K, 308 K and 318 K are used to characterize the intramolecular dynamics and thermodynamics of outer surface protein A (OspA), a key protein in the life-cycle of Borrelia burgdorferi, the causative agent of Lyme disease. It has recently been demonstrated that OspA specifically binds to the gut of the intermediate tick host (Ixodes scapularis), and that this interaction is mediated, at least in part, by residues in the C-terminal domain of OspA and Biophysics that are largely inaccessible to solvent in all X-ray structures of this protein. Our analysis of N-15 relaxation parameters in OspA shows that Medical Center, Rochester the putative-binding region contains and is surrounded by flexible residues, which could facilitate accessibility to solvent and ligands. In addition, residues with similar activation energies are clustered in a manner that suggests locally collective motions. We have used molecular modeling to show that these collective motions are consistent with a hinge-bending mechanism that exposes residues implicated in binding. Characteristic temperatures describing the energy landscape of the OspA backbone are derived from the temperature dependence of the N-H bond vector order parameters, and a comparison is made between the N and C-terminal globular domains and the unusual single-layer beta-sheet connecting them. The average characteristic temperatures in the three regions indicate that, with an increase in temperature, a larger increase in accessible conformational states occurs for N-H bond vectors in the single-layer central beta-sheet than for bond vectors in the globular N and C-terminal domains. These conformational states are accessible without disruption of hydrogen bonds, providing. a conformational entropic gain, upon increase in temperature, without a significant enthalpic penalty. This increase in heat capacity may help to explain the unexpected thermal stability of the unusual single-layer beta-sheet. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 Cornell Univ, Dept Mol Biol & Genet, Ithaca, NY 14853 USA. Univ Rochester, Dept Biochem & Biophys, Med Ctr, Rochester, NY 14642 USA. RP Nicholson, LK (reprint author), Los Alamos Natl Lab, Biosci Div, POB 1663, Los Alamos, NM 87545 USA. FU NIGMS NIH HHS [R01-GM57215] NR 55 TC 14 Z9 14 U1 0 U2 1 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD DEC 13 PY 2002 VL 324 IS 5 BP 991 EP 1002 DI 10.1016/S0022-2836(02)01146-4 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 627WW UT WOS:000179960200008 PM 12470954 ER PT J AU Alnajjar, MS Zhang, XM Gleicher, GJ Truksa, SV Franz, JA AF Alnajjar, MS Zhang, XM Gleicher, GJ Truksa, SV Franz, JA TI Equilibrium acidities and homolytic bond dissociation energies of acidic C-H bonds in alpha-arylacetophenones and related compounds SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID RADICAL STABILIZATION ENERGIES; OXIDATION POTENTIALS; DIMETHYL-SULFOXIDE; ALKYL-GROUPS; CATIONS; STABILITIES; ANIONS; VOLTAMMETRY; CARBANIONS; ENTHALPIES AB The equilibrium acidities (pK(AH)s) and the oxidation potentials of the congugate anions {E-ox(A(-))s} were determined in dimethyl sulfoxide (DMSO) for eight ketones of the structure GCOCH(3) and 20 of the structure RCOCH(2)G, (where R = alkyl, phenyl and G = alkyl, aryl). The homolytic bond dissociation energies (BDEs) for the acidic C-H bonds of the ketones were estimated using the equation BDEAH = 1.37pK(AH) + 23.1E(ox)(A(-)) + 73.3. While the equilibrium acidities of GCOCH(3) were found to be dependent on the remote substituent G, the BDE values for the C-H bonds remained essentially invariant (93.5 +/- 0.5 kcal/mol). A linear correlation between pK(AH) values and {E-ox(A(-))s} was found for the ketones. For RCOCH2G ketones, both pKAH and BDE values for the adjacent C-H bonds are sensitive to the nature of the substituent G. However, the steric bulk of the aryl group tends to exert a leveling effect on BDEs. The BDE of alpha-9-anthracenylacetophenone is higher than that of alpha-2-anthracenylacetophenone by 3 kcal/mol, reflecting significant steric inhibition of resonance in the 9-substituted system. A range of 80.7-84.4 kcal/mol is observed for RCOCH2G ketones. The results are discussed in terms of solvation, steric, and resonance effects. Ab initio density functional theory (DFT) calculations are employed to illustrate the effect of steric interactions on radical and anion geometries. The DFT results parallel the trends in the experimental BDEs of alpha-arylacetophenones. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Oregon State Univ, Dept Chem, Corvallis, OR 97330 USA. RP Alnajjar, MS (reprint author), Pacific NW Natl Lab, POB 99, Richland, WA 99352 USA. NR 55 TC 9 Z9 9 U1 1 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD DEC 13 PY 2002 VL 67 IS 25 BP 9016 EP 9022 DI 10.1021/jo020275s PG 7 WC Chemistry, Organic SC Chemistry GA 624AC UT WOS:000179736300044 PM 12467424 ER PT J AU Radike, M Warshawsky, D Caruso, J Goth-Goldstein, R Reilman, R Collins, T Yaeger, M Wang, JS Vela, N Olsen, L Schneider, J AF Radike, M Warshawsky, D Caruso, J Goth-Goldstein, R Reilman, R Collins, T Yaeger, M Wang, JS Vela, N Olsen, L Schneider, J TI Distribution and accumulation of a mixture of arsenic, cadmium, chromium, nickel, and vanadium in mouse small intestine, kidneys, pancreas, and femur following oral administration in water or feed SO JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A-CURRENT ISSUES LA English DT Article ID DRINKING-WATER; RAT ORGANS; MICE; TISSUES; COAL AB Manufactured gas plant (MCP) sites are contaminated with coal tar and may contain metals such as arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), and vanadium (V). These metals are known to cause cancer or other adverse health conditions in humans, and the extent and cost of remediating MCP sites may be influenced by the presence of these metals. Studies assessed the distribution of these metals in female B6C3F1 mice ingesting (1) a metal mixture in water or (2) an MGP mixture in NIH-31 feed. The highest metal levels were measured in the small intestine and kidneys of mice receiving the metal mixture in water. For mice receiving the metal mixture in water, levels of As, Cd, and Cr, in the small intestine, levels of As, Cd, Cr, and V in the kidneys, levels of As and Cd in the pancreas, and levels of Cr and V in the femur were significantly greater than controls at 4, 8, 72, 16, and 24 wk. Except for Ni levels in the small intestine and femur and Cr levels in the kidneys, levels of metals were much lower in mice administered the MCP mixture in feed. The highest concentrations of metals in mice ingesting the MCP mixture in feed were found in the small intestine and kidneys, but few were significantly greater than controls. Levels of As in the small intestine at 6 and 18 wk and levels of Cr in the kidneys at 12, 78, and 24 wk were significantly greater than in controls. The data suggest that tissue burdens in small intestine, kidneys, pancreas, and femur of arsenic, cadmium, chromium, and vanadium are less when metals are present as an MCP mixture in feed than as a mixture in water. The reduced distribution and accumulation of metals in the organs of mice ingesting the MCP mixture in feed compared to the levels in organs of mice ingesting the metal mixture in water suggests that metals may be less likely to accumulate in humans ingesting MCP mixtures, thereby presenting a lower overall human health risk. The data presented indicate that the matrix in which metals are present will affect the uptake of individual metals and the organ specificity. C1 Univ Cincinnati, Med Ctr, Dept Environm Hlth, Cincinnati, OH 45267 USA. Univ Cincinnati, Dept Chem, Cincinnati, OH 45267 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Warshawsky, D (reprint author), Univ Cincinnati, Med Ctr, Dept Environm Hlth, POB 670056, Cincinnati, OH 45267 USA. EM warshad@uc.edu FU NIEHS NIH HHS [5P42 ES04908-11] NR 32 TC 16 Z9 16 U1 1 U2 8 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1528-7394 J9 J TOXICOL ENV HEAL A JI J. Toxicol. Env. Health Part A PD DEC 13 PY 2002 VL 65 IS 23 BP 2029 EP 2052 DI 10.1080/00984100290071324 PG 24 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 619XN UT WOS:000179503000007 PM 12490046 ER PT J AU Dehal, P Satou, Y Campbell, RK Chapman, J Degnan, B De Tomaso, A Davidson, B Di Gregorio, A Gelpke, M Goodstein, DM Harafuji, N Hastings, KEM Ho, I Hotta, K Huang, W Kawashima, T Lemaire, P Martinez, D Meinertzhagen, IA Necula, S Nonaka, M Putnam, N Rash, S Saiga, H Satake, M Terry, A Yamada, L Wang, HG Awazu, S Azumi, K Boore, J Branno, M Chin-bow, S DeSantis, R Doyle, S Francino, P Keys, DN Haga, S Hayashi, H Hino, K Imai, KS Inaba, K Kano, S Kobayashi, K Kobayashi, M Lee, BI Makabe, KW Manohar, C Matassi, G Medina, M Mochizuki, Y Mount, S Morishita, T Miura, S Nakayama, A Nishizaka, S Nomoto, H Ohta, F Oishi, K Rigoutsos, I Sano, M Sasaki, A Sasakura, Y Shoguchi, E Shin-i, T Spagnuolo, A Stainier, D Suzuki, MM Tassy, O Takatori, N Tokuoka, M Yagi, K Yoshizaki, F Wada, S Zhang, C Hyatt, PD Larimer, F Detter, C Doggett, N Glavina, T Hawkins, T Richardson, P Lucas, S Kohara, Y Levine, M Satoh, N Rokhsar, DS AF Dehal, P Satou, Y Campbell, RK Chapman, J Degnan, B De Tomaso, A Davidson, B Di Gregorio, A Gelpke, M Goodstein, DM Harafuji, N Hastings, KEM Ho, I Hotta, K Huang, W Kawashima, T Lemaire, P Martinez, D Meinertzhagen, IA Necula, S Nonaka, M Putnam, N Rash, S Saiga, H Satake, M Terry, A Yamada, L Wang, HG Awazu, S Azumi, K Boore, J Branno, M Chin-bow, S DeSantis, R Doyle, S Francino, P Keys, DN Haga, S Hayashi, H Hino, K Imai, KS Inaba, K Kano, S Kobayashi, K Kobayashi, M Lee, BI Makabe, KW Manohar, C Matassi, G Medina, M Mochizuki, Y Mount, S Morishita, T Miura, S Nakayama, A Nishizaka, S Nomoto, H Ohta, F Oishi, K Rigoutsos, I Sano, M Sasaki, A Sasakura, Y Shoguchi, E Shin-i, T Spagnuolo, A Stainier, D Suzuki, MM Tassy, O Takatori, N Tokuoka, M Yagi, K Yoshizaki, F Wada, S Zhang, C Hyatt, PD Larimer, F Detter, C Doggett, N Glavina, T Hawkins, T Richardson, P Lucas, S Kohara, Y Levine, M Satoh, N Rokhsar, DS TI The draft genome of Ciona intestinalis: Insights into chordate and vertebrate origins SO SCIENCE LA English DT Article ID GENE-EXPRESSION PROFILES; ASCIDIAN EMBRYOS; HOMEOBOX GENES; EVOLUTION; CLUSTER; SYSTEM; DROSOPHILA; SEQUENCE; BIOLOGY; PLANT AB The first chordates appear in the fossil record at the time of the Cambrian explosion, nearly 550 million years ago. The modern ascidian tadpole represents a plausible approximation to these ancestral chordates. To illuminate the origins of chordate and vertebrates, we generated a draft of the protein-coding portion of the genome of the most studied ascidian, Ciona intestinalis. The Ciona genome contains similar to16,000 protein-coding genes, similar to the number in other invertebrates, but only half that found in vertebrates. Vertebrate gene families are typically found in simplified form in Ciona, suggesting that ascidians contain the basic ancestral complement of genes involved in cell signaling and development. The ascidian genome has also acquired a number of lineage-specific innovations, including a group of genes engaged in cellulose metabolism that are related to those in bacteria and fungi. C1 US DOE, Joint Genome Inst, Walnut Creek, CA 94598 USA. Kyoto Univ, Grad Sch Sci, Dept Zool, Kyoto 6068502, Japan. Marine Biol Labs, Woods Hole, MA 02543 USA. Serono Reprod Biol Inst, Rockland, MA 02370 USA. Univ Queensland, Dept Zool & Entomol, Brisbane, Qld 4072, Australia. Stanford Univ, Sch Med, Dept Pathol, Stanford, CA 93950 USA. Univ Calif Berkeley, Dept Mol & Cellular Biol, Div Genet, Berkeley, CA 94720 USA. McGill Univ, Montreal Neurol Inst, Montreal, PQ H3A 2T5, Canada. Natl Inst Genet, Mishima, Shizuoka 4118540, Japan. Kyoto Univ, Inst Chem Res, Bioinformat Ctr, Kyoto 6110011, Japan. IBDM, LGPD, F-13288 Marseille 09, France. Dalhousie Univ, Life Sci Ctr, Halifax, NS B3H 4J1, Canada. Univ Tokyo, Grad Sch Sci, Dept Biol Sci, Tokyo 1130033, Japan. Tokyo Metropolitan Univ, Grad Sch Sci, Dept Biol Sci, Tokyo 1920397, Japan. Tohoku Univ, Inst Dev Aging & Canc, Dept Mol Immunol, Aoba Ku, Sendai, Miyagi 9808575, Japan. H Lee Moffitt Canc Ctr & Res Inst, Drug Discovery Program, Tampa, FL 33612 USA. Hokkaido Univ, Grad Sch Pharmaceut Sci, Dept Biochem, Sapporo, Hokkaido 0600812, Japan. Stn Zool Anton Dohrn, I-80121 Naples, Italy. IBM Corp, Thomas J Watson Res Ctr, Yorktown Hts, NY 10598 USA. Tohoku Univ, Grad Sch Sci, Asamushi Marine Biol Stn, Asamushi, Aomori 0393501, Japan. Univ Maryland, College Pk, MD 20742 USA. Univ Calif San Francisco, Dept Biochem & Biophys, Programs Dev Biol Genet & Human Genet, San Francisco, CA 94143 USA. Univ Edinburgh, Inst Cell & Mol Biol, Wellcome Trust Ctr Cell Biol, Edinburgh EH9 3JR, Midlothian, Scotland. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Ctr Integrat Genom, Berkeley, CA 94720 USA. RP Natl Inst Genet, Mishima, Shizuoka 4118540, Japan. EM ykohara@lab.nig.ac.jp; mlevine@uclink4.berkeley.edu; satoh@ascidian.zool.kyoto-u.ac.jp; dsrokhsar@lbl.gov RI Kawashima, Takeshi/M-4510-2015; Satou, Yutaka/K-7131-2012; Putnam, Nicholas/B-9968-2008; Satoh, Nori/C-4123-2009; Di Gregorio, Anna/C-4766-2008; Lemaire, Patrick/D-4237-2009; Lemaire, Patrick/B-5560-2012; Campbell, Robert/G-4112-2012; NONAKA, MASARU/G-4929-2014; Wang, Hong-Gang/A-3018-2015; Francino, M. Pilar/H-9090-2015; Matassi, Giorgio/G-6301-2014 OI Satou, Yutaka/0000-0001-5193-0708; Putnam, Nicholas/0000-0002-1315-782X; Lemaire, Patrick/0000-0003-4925-2009; Francino, M. Pilar/0000-0002-4510-5653; Matassi, Giorgio/0000-0003-4923-226X FU NICHD NIH HHS [HD-37105] NR 90 TC 1104 Z9 1141 U1 9 U2 104 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 DEC 13 PY 2002 VL 298 IS 5601 BP 2157 EP 2167 DI 10.1126/science.1080049 PG 11 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 624RA UT WOS:000179773700039 PM 12481130 ER PT J AU Comstock, JM Ackerman, TP Mace, GG AF Comstock, JM Ackerman, TP Mace, GG TI Ground-based lidar and radar remote sensing of tropical cirrus clouds at Nauru Island: Cloud statistics and radiative impacts SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE tropical cirrus; tropical tropopause; lidar remote sensing ID STRATOSPHERIC WATER-VAPOR; OPTICAL-PROPERTIES; MICROPULSE LIDAR; WESTERN PACIFIC; WARM POOL; TROPOPAUSE; THIN; PARAMETERIZATION; MIDLATITUDE; ANVILS AB [1] Ground-based active and passive remote sensing instrumentation are combined to derive radiative and macrophysical properties of tropical cirrus clouds. Eight months of cirrus observations at the Department of Energy Atmospheric Radiation Measurement site located on Nauru Island provide independent retrieval of cloud height and visible optical depth using lidar and radar techniques. Comparisons reveal the millimeter cloud radar does not detect 13% of cirrus clouds with a cloud base higher than 15 km that are detected by the lidar. Lidar and radar cloud heights demonstrate good agreement when the cloud lies below 15 km. Radar and lidar retrievals of visible optical depth also compare well for all but the optically thinnest clouds. Cloud occurrence at Nauru as measured by lidar reveal clear-sky conditions, low clouds, and high clouds occur on average 40%, 16%, and 44% of the time, respectively. Analysis of observed cirrus macrophysical and radiative properties suggests that two different types of cirrus exist in the tropical western Pacific: high, thin, laminar cirrus with cloud base higher than 15 km, and lower, physically thicker, more structured cirrus clouds. Differences in cirrus types are probably linked to their formation mechanisms. Radiosonde profiles of temperature and equivalent potential temperature near the tropical tropopause show a clear transition between neutrally stable and stable air at similar to 15 km, which may also explain the presence of two distinct cirrus types. Radiative heating rate and cloud forcing calculations for specific cirrus cases reveal the impact of tropical cirrus clouds on the Earth's radiation budget. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. RP Comstock, JM (reprint author), Pacific NW Natl Lab, POB 999,MSIN K9-24, Richland, WA 99352 USA. EM jennifer.comstock@pnl.gov; ackerman@pnl.gov; mace@met.utah.edu NR 42 TC 144 Z9 148 U1 2 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 12 PY 2002 VL 107 IS D23 AR 4714 DI 10.1029/2002JD002203 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 647VA UT WOS:000181113700002 ER PT J AU Shkrob, IA Sauer, MC Jonah, CD Takahashi, K AF Shkrob, IA Sauer, MC Jonah, CD Takahashi, K TI Ionic and neutral species in pulse radiolysis of supercritical CO2. 1. Transient absorption spectroscopy, electric field effect, and charge dynamics SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID HIGH-MOBILITY IONS; GAS-PHASE ION; CARBON-DIOXIDE; CROSS-SECTIONS; PHOTOELECTRON-SPECTROSCOPY; PHOTODISSOCIATION DYNAMICS; SOLVENT ANIONS; AB-INITIO; CLUSTER; SPECTRA AB Transient absorption spectroscopy was used to study the mechanism for radiolysis of dense, liquidlike supercritical (SO CO2 (T = 41 degreesC, rho = 0.84 g/cm(3)). The 350-1500 nm spectra are decomposed into. the contributions from the solvent radical cation, solvent radical anion, and a long-lived neutral product that we associate with singlet carbon trioxide, CO3((1)A(1)). These three species are characterized by their optical spectra, chemical behavior, kinetics, and the response of these kinetics to external electric field. The following mechanism for radiolysis Of sc CO2 is suggested: Ionization of the solvent yields 5 pairs per 100 eV. Most of these pairs are comprised of the solvent hole and a thermalized quasifree electron; the prompt yield of CO3- is <3% of the total ion yield. The electrons are trapped by the solvent in <200 ps. Because of high election mobility, most, of this trapping occurs after the charges escape each other's Coulomb field. Because of cross recombination of the electrons with nongeminate solvent holes,. the lifetime of the quasifree electrons is further reduced. A theoretical model that accounts for these dynamics is suggested. It is shown that di- and triatomic molecules donate an electron to the solvent hole, and the resulting solute cations polymerize. Exotic ion species, such as (N2O)(2)(+) and (CO)(n)(+), can be produced this way. Using SC CO2 provides an opportunity to study such multimer cations in liquid solution. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Hokkaido Univ, Div Quantum Energy Engn, Grad Sch Engn, Sapporo, Hokkaido 0608628, Japan. RP Shkrob, IA (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Takahashi, Kenji/C-8846-2011; Takahashi, Kenji/F-4885-2014 NR 85 TC 20 Z9 20 U1 3 U2 16 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 DEC 12 PY 2002 VL 106 IS 49 BP 11855 EP 11870 DI 10.1021/jp021494k PG 16 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 623YG UT WOS:000179732000002 ER PT J AU Shkrob, IA AF Shkrob, IA TI Ionic species in pulse radiolysis of supercritical carbon dioxide. 2. Ab initio studies on the structure and optical properties of (CO2)(n)(+), (CO2)(2)(-), and CO3- ions SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID GAS-PHASE ION; PHOTOELECTRON-SPECTROSCOPY; PHOTODISSOCIATION DYNAMICS; PHOTO-DISSOCIATION; INFRARED-SPECTRA; NEGATIVE-IONS; SOLID NEON; CLUSTER; THERMOCHEMISTRY; RESONANCE AB Gas-phase (CO2)(2-4)(+) cations and (CO2)(2)(-), CO3-, CO3-.H2O and CO3-.CO2 anions have been examined using density functional theory calculations. It is shown that the lowest energy (CO2)(n)(+) cations are C-2h symmetric "ladder" structures with complete delocalization of charge and spin between the monomer units. These cations absorb in the visible due to a charge resonance band that involves their lowest B-2(u) and (2)A(g) states. The "ladder" structure accounts for several trends observed in the photodestruction spectra of the (CO2)(n)(+) cations. For the (CO2)(2)(+) dimer cation; the energy and the oscillator strength of the charge resonance band compare favorably with these parameters for the solvent radical cation in supercritical (SC) CO2. A close similarity between the VIS spectra of the (N2O)(2)(+) dimer cation (in sc CO2) and the solvent cation suggests that the latter has the (CO2)(2)(+) dimer cation as the chromophore core. It is demonstrated that optical, Raman, and magnetic resonance spectra of the carbonate radical anion, CO3-, can be consistently accounted for by a C-2nu symmetric structure with the unique O-C-O angle of approximate to113degrees (in water) to approximate to 100degrees (in carbonate minerals). The oscillator strength of the A (2)A(1) <-- X B-2(2) transition in the visible correlates with this O-C-O angle. In aqueous CO3-, the trigonal distortion is due to hydrogen bonding to a single water molecule. In SC CO2 (and other nonpolar liquids), the trigonal distortion is weak, and CO3- should be a poor light absorber. This may be the reason no dissociative electron capture in,sc CO2 has been observed,by optical spectroscopy. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Shkrob, IA (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 72 TC 17 Z9 17 U1 4 U2 24 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 DEC 12 PY 2002 VL 106 IS 49 BP 11871 EP 11881 DI 10.1021/jp0214918 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 623YG UT WOS:000179732000003 ER PT J AU Caldeira, K AF Caldeira, K TI What has posterity done for us? It's not the point SO NATURE LA English DT Letter C1 Lawrence Livermore Natl Lab, Climate & Carbon Cycle Grp, Livermore, CA 94550 USA. RP Caldeira, K (reprint author), Lawrence Livermore Natl Lab, Climate & Carbon Cycle Grp, 7000 E Ave,L-103, Livermore, CA 94550 USA. RI Caldeira, Ken/E-7914-2011 NR 1 TC 0 Z9 0 U1 0 U2 1 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD DEC 12 PY 2002 VL 420 IS 6916 BP 605 EP 605 DI 10.1038/420605c PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 624GK UT WOS:000179751800017 PM 12478262 ER PT J AU West, GB Enquist, BJ Brown, JH AF West, GB Enquist, BJ Brown, JH TI Ontogenetic growth - Modelling universality and scaling - Reply SO NATURE LA English DT Editorial Material ID GENERAL-MODEL C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Santa Fe Inst, Santa Fe, NM 87501 USA. Univ Arizona, Dept Ecol & Evolutionary Biol, Tucson, AZ 85721 USA. Univ New Mexico, Dept Biol, Albuquerque, NM 87131 USA. RP West, GB (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 4 TC 12 Z9 12 U1 0 U2 8 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD DEC 12 PY 2002 VL 420 IS 6916 BP 626 EP 627 DI 10.1038/420626b PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 624GK UT WOS:000179751800033 ER PT J AU Gilman, AG Simon, MI Bourne, HR Harris, BA Long, R Ross, EM Stull, JT Taussig, R Bourne, HR Arkin, AP Cobb, MH Cyster, JG Devreotes, PN Ferrell, JE Fruman, D Gold, M Weiss, A Stull, JT Berridge, MJ Cantley, LC Catterall, WA Coughlin, SR Olson, EN Smith, TF Brugge, JS Botstein, D Dixon, JE Hunter, T Lefkowitz, RJ Pawson, AJ Sternberg, PW Varmus, H Subramaniam, S Sinkovits, RS Li, J Mock, D Ning, YH Saunders, B Sternweis, PC Hilgemann, D Scheuermann, RH DeCamp, D Hsueh, R Lin, KM Ni, Y Seaman, WE Simpson, PC O'Connell, TD Roach, T Simon, MI Choi, S Eversole-Cire, P Fraser, I Mumby, MC Zhao, YM Brekken, D Shu, HJ Meyer, T Chandy, G Do Heo, W Liou, J O'Rourke, N Verghese, M Mumby, SM Han, HP Brown, HA Forrester, JS Ivanova, P Milne, SB Casey, PJ Harden, TK Arkin, AP Doyle, J Gray, ML Meyer, T Michnick, S Schmidt, MA Toner, M Tsien, RY Natarajan, M Ranganathan, R Sambrano, GR AF Gilman, AG Simon, MI Bourne, HR Harris, BA Long, R Ross, EM Stull, JT Taussig, R Bourne, HR Arkin, AP Cobb, MH Cyster, JG Devreotes, PN Ferrell, JE Fruman, D Gold, M Weiss, A Stull, JT Berridge, MJ Cantley, LC Catterall, WA Coughlin, SR Olson, EN Smith, TF Brugge, JS Botstein, D Dixon, JE Hunter, T Lefkowitz, RJ Pawson, AJ Sternberg, PW Varmus, H Subramaniam, S Sinkovits, RS Li, J Mock, D Ning, YH Saunders, B Sternweis, PC Hilgemann, D Scheuermann, RH DeCamp, D Hsueh, R Lin, KM Ni, Y Seaman, WE Simpson, PC O'Connell, TD Roach, T Simon, MI Choi, S Eversole-Cire, P Fraser, I Mumby, MC Zhao, YM Brekken, D Shu, HJ Meyer, T Chandy, G Do Heo, W Liou, J O'Rourke, N Verghese, M Mumby, SM Han, HP Brown, HA Forrester, JS Ivanova, P Milne, SB Casey, PJ Harden, TK Arkin, AP Doyle, J Gray, ML Meyer, T Michnick, S Schmidt, MA Toner, M Tsien, RY Natarajan, M Ranganathan, R Sambrano, GR CA Alliance Cellular Signaling TI Overview of the Alliance for Cellular Signaling SO NATURE LA English DT Editorial Material AB The Alliance for Cellular Signaling is a large-scale collaboration designed to answer global questions about signalling networks. Pathways will be studied intensively in two cells-B lymphocytes (the cells of the immune system) and cardiac myocytes-to facilitate quantitative modelling. One goal is to catalyse complementary research in individual laboratories; to facilitate this, all alliance data are freely available for use by the entire research community. C1 Univ Texas, SW Med Ctr, Dept Pharmacol, Dallas, TX 75390 USA. Univ Texas, SW Med Ctr, Dept Physiol, Dallas, TX 75390 USA. Univ Texas, SW Med Ctr, Dept Pathol, Dallas, TX 75390 USA. Univ Texas, SW Med Ctr, Dept Biochem, Dallas, TX 75390 USA. Univ Texas, SW Med Ctr, Dept Mol Biol & Oncol, Dallas, TX 75390 USA. CALTECH, Div Biol, Pasadena, CA 91125 USA. CALTECH, Howard Hughes Med Inst, Dept Biol, Pasadena, CA 91125 USA. Univ Calif San Francisco, Dept Mol & Cellular Pharmacol, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Microbiol & Immunol, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Med, San Francisco, CA 94143 USA. Univ Calif San Francisco, Inst Cardiovasc Res, San Francisco, CA 94143 USA. Aventis Pharmaceut, Bridgewater, NJ 08807 USA. NIGMS, Pharmacol Physiol & Biol Chem Div, NIH, Bethesda, MD 20892 USA. Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Dept Bioengn, Berkeley, CA 94720 USA. Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Dept Chem, Berkeley, CA 94720 USA. Johns Hopkins Univ, Dept Cell Biol & Anat, Baltimore, MD 21205 USA. Stanford Univ, Sch Med, Ctr Clin Sci Res, Stanford, CA 94305 USA. Stanford Univ, Sch Med, Dept Genet, Stanford, CA 94305 USA. Stanford Univ, Sch Med, Dept Mol Pharmacol, Stanford, CA 94305 USA. Univ Calif Irvine, Dept Mol Biol & Biochem, Irvine, CA 92697 USA. Univ British Columbia, Dept Microbiol & Immunol, Vancouver, BC V6T 1Z3, Canada. Babraham Inst, Cambridge CB2 4AT, England. Harvard Univ, Sch Med, Beth Israel Deaconess Med Ctr, Dept Cell Biol, Boston, MA 02215 USA. Harvard Univ, Sch Med, Beth Israel Deaconess Med Ctr, Dept Med, Boston, MA 02215 USA. Univ Washington, Sch Med, Dept Pharmacol, Seattle, WA 98195 USA. Harvard Univ, Sch Med, Dept Cell Biol, Boston, MA 02115 USA. Boston Univ, BMERC, Boston, MA 02215 USA. Univ Michigan, Sch Med, Dept Biol Chem, Ann Arbor, MI 48109 USA. Salk Inst Biol Studies, San Diego, CA 92186 USA. Duke Univ, Med Ctr, Howard Hughes Med Inst, Durham, NC 27710 USA. Duke Univ, Med Ctr, Dept Pharmacol & Canc Biol, Durham, NC 27710 USA. Mt Sinai Hosp, Toronto, ON M5G 1X5, Canada. Mem Sloan Kettering Canc Ctr, New York, NY 10021 USA. Univ Calif San Diego, San Diego Supercomp Ctr, La Jolla, CA 92037 USA. Vet Affairs Med Ctr, Dept Rheumatol, San Francisco, CA 94121 USA. Vet Affairs Med Ctr, Dept Cardiol, San Francisco, CA 94121 USA. Vanderbilt Univ, Dept Pharmacol, Nashville, TN 37232 USA. Univ N Carolina, Sch Med, Dept Pharmacol, Chapel Hill, NC 27599 USA. MIT, Harvard MIT Div Hlth Sci & Technol, Dept Elect & Med Engn, Cambridge, MA 02139 USA. MIT, Dept Elect Engn & Comp Sci, Dept Elect & Med Engn, Cambridge, MA 02139 USA. Univ Montreal, Dept Biochem, Montreal, PQ H3C 3J7, Canada. Shriners Burn Hosp, Boston, MA 02114 USA. Univ Calif San Diego, Howard Hughes Med Inst, La Jolla, CA 92093 USA. RP Gilman, AG (reprint author), Univ Texas, SW Med Ctr, Dept Pharmacol, Dallas, TX 75390 USA. RI Arkin, Adam/A-6751-2008; Brekken, Deirdre/I-7999-2012; Ivanova, Pavlina/K-8307-2012; Cantley, Lewis/D-1800-2014; O'Connell, Timothy/D-5048-2013; OI Arkin, Adam/0000-0002-4999-2931; Cantley, Lewis/0000-0002-1298-7653; Brekken, Deirdre/0000-0003-2790-0108; Natarajan, Madhusudan/0000-0003-1607-2917; Cobb, Melanie/0000-0003-0833-5473 FU NCI NIH HHS [T32 CA121938] NR 0 TC 343 Z9 346 U1 2 U2 24 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD DEC 12 PY 2002 VL 420 IS 6916 BP 703 EP 706 DI 10.1038/nature01304 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 624GK UT WOS:000179751800054 PM 12478301 ER PT J AU Bai, JZ Ban, Y Bian, JG Blum, I Cai, X Chang, JF Chen, HF Chen, HS Chen, J Chen, J Chen, JC Chen, YB Chi, SP Chu, YP Cui, XZ Dai, YS Dong, LY Du, ZZ Dunwoodie, W Fang, J Fang, SS Fu, HY Fu, LP Gao, CS Gao, YN Gong, MY Gratton, P Gu, SD Guo, YN Guo, YQ Guo, ZJ Han, SW Harris, FA He, J He, KL He, M He, X Heng, YK Hong, T Hu, HM Hu, T Huang, GS Huang, XP Izen, JM Ji, XB Jiang, CH Jiang, XS Jin, DP Jin, S Jin, Y Jones, BD Ke, ZJ Kong, D Lai, YF Li, G Li, HH Li, J Li, JC Li, QJ Li, RY Li, W Li, WG Li, XQ Liu, CF Liu, F Liu, HM Liu, JP Liu, RG Liu, TR Liu, Y Liu, ZA Liu, Z Lou, XC Lowery, B Lu, GR Lu, F Lu, HJ Lu, JG Lu, ZJ Luo, XL Ma, EC Ma, FC Ma, JM Malchow, R Mao, ZP Meng, XC Mo, XH Nie, J Nie, ZD Olsen, SL Paluselli, D Pan, LJ Panetta, J Peng, HP Porter, F Qi, ND Qian, CD Qiu, JF Rong, G Shen, DL Shen, H Shen, XY Sheng, HY Shi, F Standifird, J Sun, HS Sun, SS Sun, YZ Tang, X Tian, D Toki, W Tong, GL Varner, GS Wang, J Wang, JZ Wang, L Wang, LS Wang, M Wang, M Wang, P Wang, PL Wang, WF Wang, YF Wang, Y Wang, Z Wang, Z Wang, Z Weaver, M Wei, CL Wu, N Xia, XM Xie, XX Xu, GF Xu, Y Xue, ST Yan, ML Yan, WB Yang, CY Yang, GA Yang, H Ye, MH Ye, SW Ye, YX Ying, J Yu, CS Yu, GW Yuan, CZ Yuan, JM Yuan, Y Yue, Q Zeng, Y Zhang, BX Zhang, BY Zhang, CC Zhang, DH Zhang, HY Zhang, J Zhang, JW Zhang, L Zhang, LS Zhang, QJ Zhang, SQ Zhang, XY Zhang, YY Zhang, YY Zhang, ZP Zhao, D Zhao, JW Zhao, JW Zhao, PP Zhao, WR Zhao, YB Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhong, XC Zhou, BQ Zhou, GM Zhou, L Zhu, KJ Zhu, QM Zhu, YC Zhu, YS Zhu, ZA Zhuang, BA Zou, BS AF Bai, JZ Ban, Y Bian, JG Blum, I Cai, X Chang, JF Chen, HF Chen, HS Chen, J Chen, J Chen, JC Chen, YB Chi, SP Chu, YP Cui, XZ Dai, YS Dong, LY Du, ZZ Dunwoodie, W Fang, J Fang, SS Fu, HY Fu, LP Gao, CS Gao, YN Gong, MY Gratton, P Gu, SD Guo, YN Guo, YQ Guo, ZJ Han, SW Harris, FA He, J He, KL He, M He, X Heng, YK Hong, T Hu, HM Hu, T Huang, GS Huang, XP Izen, JM Ji, XB Jiang, CH Jiang, XS Jin, DP Jin, S Jin, Y Jones, BD Ke, ZJ Kong, D Lai, YF Li, G Li, HH Li, J Li, JC Li, QJ Li, RY Li, W Li, WG Li, XQ Liu, CF Liu, F Liu, HM Liu, JP Liu, RG Liu, TR Liu, Y Liu, ZA Liu, Z Lou, XC Lowery, B Lu, GR Lu, F Lu, HJ Lu, JG Lu, ZJ Luo, XL Ma, EC Ma, FC Ma, JM Malchow, R Mao, ZP Meng, XC Mo, XH Nie, J Nie, ZD Olsen, SL Paluselli, D Pan, LJ Panetta, J Peng, HP Porter, F Qi, ND Qian, CD Qiu, JF Rong, G Shen, DL Shen, H Shen, XY Sheng, HY Shi, F Standifird, J Sun, HS Sun, SS Sun, YZ Tang, X Tian, D Toki, W Tong, GL Varner, GS Wang, J Wang, JZ Wang, L Wang, LS Wang, M Wang, M Wang, P Wang, PL Wang, WF Wang, YF Wang, Y Wang, Z Wang, Z Wang, Z Weaver, M Wei, CL Wu, N Xia, XM Xie, XX Xu, GF Xu, Y Xue, ST Yan, ML Yan, WB Yang, CY Yang, GA Yang, H Ye, MH Ye, SW Ye, YX Ying, J Yu, CS Yu, GW Yuan, CZ Yuan, JM Yuan, Y Yue, Q Zeng, Y Zhang, BX Zhang, BY Zhang, CC Zhang, DH Zhang, HY Zhang, J Zhang, JW Zhang, L Zhang, LS Zhang, QJ Zhang, SQ Zhang, XY Zhang, YY Zhang, YY Zhang, ZP Zhao, D Zhao, JW Zhao, JW Zhao, PP Zhao, WR Zhao, YB Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhong, XC Zhou, BQ Zhou, GM Zhou, L Zhu, KJ Zhu, QM Zhu, YC Zhu, YS Zhu, ZA Zhuang, BA Zou, BS TI A measurement of psi (2S) resonance parameters SO PHYSICS LETTERS B LA English DT Article ID RADIATIVE-CORRECTIONS; BHABHA SCATTERING; E+E ANNIHILATION; CROSS-SECTION; DECAY; DISTRIBUTIONS; J/PSI; PSI(2S)->PI(+)PI(-)J/PSI; ENERGY AB Cross sections for e(+)e(-) --> hadrons, pi(+)pi(-)J/psi, and mu(+)mu(-) have been measured in the vicinity of the psi(2S) resonance using the BESII detector operated at the BEPC. The psi(2S) total width; partial widths to hadrons, pi(+)pi(-)J/psi, leptons; and corresponding branching fractions have been determined to be Gamma(t) = 264 +/- 27 keV; Gamma(h) = 258 +/- 26 keV, Gamma(pi+pi-J/psi) = 85.4 +/- 18.7 keV, and Gamma(l) = 2.44 +/- 0.21 keV; and B-h = (97.79 +/- 0.15)%, Bpi+pi-J/psi (32.3 +/- 1.4)%, and B-l = (0.93 +/- 0.08)%, respectively. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Inst High Energy Phys, Beijing 100039, Peoples R China. CALTECH, Pasadena, CA 91125 USA. China Ctr Adv Sci & Technol, Beijing 100080, Peoples R China. Colorado State Univ, Ft Collins, CO 80523 USA. Henan Normal Univ, Xinxiang 453002, Peoples R China. Huazhong Normal Univ, Wuhan 430079, Peoples R China. Hunan Univ, Changsha 410082, Peoples R China. Liaoning Univ, Shenyang 110036, Peoples R China. Nankai Univ, Tianjin 300071, Peoples R China. Peking Univ, Beijing 100871, Peoples R China. Shandong Univ, Jinan 250100, Peoples R China. Shanghai Jiao Tong Univ, Shanghai 200030, Peoples R China. Sichuan Univ, Chengdu 610064, Peoples R China. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Tsing Hua Univ, Beijing 100084, Peoples R China. Univ Hawaii, Honolulu, HI 96822 USA. Univ Sci & Technol China, Hefei 230026, Peoples R China. Univ Texas, Richardson, TX 75083 USA. Wuhan Univ, Wuhan 430072, Peoples R China. Zhejiang Univ, Hangzhou 310028, Peoples R China. RP Bai, JZ (reprint author), Inst High Energy Phys, Beijing 100039, Peoples R China. RI Chen, Jie/H-6210-2011 NR 36 TC 33 Z9 34 U1 0 U2 9 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 DEC 12 PY 2002 VL 550 IS 1-2 BP 24 EP 32 AR PII S0370-2693(02)02909-X DI 10.1016/S0370-2693(02)02909-X PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 624UE UT WOS:000179779300004 ER PT J AU Ginosar, DM Coates, K Thompson, DN AF Ginosar, DM Coates, K Thompson, DN TI The effects of supercritical propane on the alkylation of toluene with ethylene over USY and sulfated zirconia catalysts SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID NEAR-CRITICAL REGIONS; PARA-SELECTIVITY; REFORMING CATALYST; REACTION MIXTURES; ETHYLATION; DEPOSITION; SILYLATION; SURFACE; HZSM-5; COKING AB The alkylation of toluene with ethylene over microporous USY zeolite and mesoporous sulfated zirconia (S/ZrO2) catalysts was explored at liquid, near-critical liquid, and supercritical conditions using propane as the supercritical cosolvent. Liquid, near-critical liquid, and supercritical conditions were examined for their effects on product selectivity and catalyst activity maintenance. The S/ZrO2 catalyst demonstrated alkylation activity almost exclusively, whereas the USY catalyst demonstrated both alkylation and cracking/disproportionation activities. Near-critical and supercritical reaction conditions improved product selectivity with the USY catalyst through the suppression of disproportionation reactions and enhanced ortho- and paraethyltoluene selectivity. However, the addition of the supercritical cosolvent resulted in increased deactivation for both the S/ZrO2 and USY catalysts, with deactivation increasing with propane mole fraction. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Ginosar, DM (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. RI Ginosar, Daniel/C-2357-2017 OI Ginosar, Daniel/0000-0002-8522-1659 NR 23 TC 12 Z9 12 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD DEC 11 PY 2002 VL 41 IS 25 BP 6537 EP 6545 DI 10.1021/ie0202569 PG 9 WC Engineering, Chemical SC Engineering GA 623QX UT WOS:000179715300036 ER PT J AU Kassianov, EI Kogan, YL AF Kassianov, EI Kogan, YL TI Spectral dependence of radiative horizontal transport in stratocumulus clouds and its effect on near-IR absorption SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE radiative horizontal transport; cloud inhomogeneity; spectral and broadband absorption ID EDDY SIMULATION-MODEL; AIRCRAFT MEASUREMENTS; SOLAR-RADIATION; EXPLICIT MICROPHYSICS; ATMOSPHERE; FLUXES; INHOMOGENEITY AB [1] The spectral dependence of the radiative horizontal transport (the horizontal transport of radiative energy) E and its effect on the accuracy of spectral and broadband absorption retrieval in the near-infrared (IR) wavelength range was investigated using a large-eddy simulation (LES) cloud model with explicit microphysics and a three-dimensional Monte Carlo radiative transfer model. Two typical types of marine clouds representing inhomogeneous overcast and broken stratocumulus clouds have been simulated. We demonstrate that (1) the basic statistics (e. g., variance and correlation function) of the horizontal transport are wavelength-dependent and (2) the estimates of spectral and broadband absorption with a given accuracy (e. g., rmse similar to4%) may require the use of different spatial resolutions. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Oklahoma, Cooperat Inst Mesoscale Meteorol Studies, Norman, OK 73019 USA. RP Pacific NW Natl Lab, 902 Battelle Blvd,POB 999, Richland, WA 99352 USA. EM evgueni.kassianov@dpnl.gov NR 37 TC 11 Z9 11 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 11 PY 2002 VL 107 IS D23 AR 4712 DI 10.1029/2002JD002103 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 647UZ UT WOS:000181113600005 ER PT J AU Liu, NG Yu, K Smarsly, B Dunphy, DR Jiang, YB Brinker, CJ AF Liu, NG Yu, K Smarsly, B Dunphy, DR Jiang, YB Brinker, CJ TI Self-directed assembly of photoactive hybrid silicates derived from an azobenzene-bridged silsesquioxane SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID FILMS C1 Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87106 USA. Univ New Mexico, Ctr Microengineered Mat, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Brinker, CJ (reprint author), Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87106 USA. EM cjbrink@sandia.gov RI Smarsly, Bernd/G-8514-2011; ye, bin/K-7828-2012; 牛, 开心/C-3081-2014 NR 13 TC 95 Z9 96 U1 0 U2 31 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 DEC 11 PY 2002 VL 124 IS 49 BP 14540 EP 14541 DI 10.1021/ja027991w PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 622RP UT WOS:000179661000017 PM 12465956 ER PT J AU Zhan, CG Zheng, F Dixon, DA AF Zhan, CG Zheng, F Dixon, DA TI Electron affinities of Al-n clusters and multiple-fold aromaticity of the square Al-4(2-) structure SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; ALUMINUM CLUSTERS; TRIPLE EXCITATIONS; WAVE-FUNCTIONS; SPECTROSCOPY; ENERGIES; POTENTIALS; SPECTRA; STATE AB The concept of aromaticity was first invented to account for the unusual stability of planar organic molecules with 4n + 2 delocalized pi electrons. Recent photoelectron spectroscopy experiments on all-metal MAI(4)(-) systems with an approximate square planar Al-4(2-) unit and an alkali metal led to the suggestion that Al-4(2-) is aromatic. The square Al-4(2-) structure was recognized as the prototype of a new family of aromatic molecules. High-level ab initio calculations based on extrapolating CCSD(T)/aug-cc-pVxZ (x = D, T, and Q) to the complete basis set limit were used to calculate the first electron affinities of Al-n, = 0-4. The calculated electron affinities, 0.41 eV (n = 0), 1.51 eV (n = 1), 1.89 eV (n = 3), and 2.18 eV (n = 4), are all in excellent agreement with available experimental data. On the basis of the high-level ab initio quantum chemical calculations, we can estimate the resonance energy and show that it is quite large, large enough to stabilize Al-4(2-) with respect to Al-4. Analysis of the calculated results shows that the aromaticity of Al-4(2-) is unusual and different from that of C6H6, Particularly, compared to the usual (1-fold) pi aromaticity in C6H6, which may be represented by two Kekule structures sharing a common a bond framework, the square Al-4(2-) structure has an unusual "multiple-fold" aromaticity determined by three independent delocalized (pi and sigma) bonding systems, each of which satisfies the 4n + 2 electron counting rule, leading to a total of 4 x 4 x 4 = 64 potential resonating Kekule-like structures without a common a frame. We also discuss the 2-fold aromaticity (pi plus sigma) of the Al-3(-) anion, which can be represented by 3 x 3 = 9 potential resonating Kekule-like structures, each with two localized chemical bonds. These results lead us to suggest a general approach (applicable to both organic and inorganic molecules) for examining delocalized chemical bonding. The possible electronic contribution to the aromaticity of a molecule should not be limited to only one particular delocalized bonding system satisfying a certain electron counting rule of aromaticity. More than one independent delocalized bonding system can simultaneously satisfy the electron counting rule of aromaticity, and therefore, a molecular structure could have multiple-fold aromaticity. C1 Columbia Univ, Coll Phys & Surg, Dept Med, New York, NY 10032 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Washington State Univ, Dept Comp Sci & Engn, Richland, WA 99352 USA. RP Zhan, CG (reprint author), Columbia Univ, Coll Phys & Surg, Dept Med, New York, NY 10032 USA. NR 59 TC 145 Z9 146 U1 2 U2 19 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 DEC 11 PY 2002 VL 124 IS 49 BP 14795 EP 14803 DI 10.1021/ja021026o PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 622RP UT WOS:000179661000054 PM 12465993 ER PT J AU Jeon, D Merminga, L Krafft, G Yunn, B Sundelin, R Delayen, J Kim, S Doleans, M AF Jeon, D Merminga, L Krafft, G Yunn, B Sundelin, R Delayen, J Kim, S Doleans, M TI Cumulative beam break-up study of the spallation neutron source superconducting linac SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE cumulative; beam breakup; superconducting linac; instability; HOM AB Beam instabilities due to High Order Modes (HOMs) are a concern to superconducting (SC) linacs such as the Spallation Neutron Source (SNS) linac. The effects of pulsed mode operation on transverse and longitudinal beam breakup instability are studied for H- beam in a consistent manner for the first time. Numerical simulation indicates that cumulative transverse beam breakup instabilities are not a concern in the SNS SC linac, primarily due to the heavy mass of H- beam and the HOM frequency spread resulting from manufacturing tolerances. As little as +/-0.1 MHz HOM frequency spread stabilizes all the instabilities from both transverse HOMs, and also acts to stabilize the longitudinal HOMs. Such an assumed frequency spread of +/-0.1 MHz HOM is small, and hence conservative compared with measured values of sigma = 0.00109(f(HOM) - f(0))/f(0) obtained from Cornell and the Jefferson Lab Free Electron Laser cavities. However, a few cavities may hit resonance lines and generate a high heat load. It is therefore prudent to have HOM dampers to avoid the danger of quenching a cavity. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, SNS Project, Oak Ridge, TN 37830 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Jeon, D (reprint author), Oak Ridge Natl Lab, SNS Project, 701 Scarboro Rd, Oak Ridge, TN 37830 USA. RI Jeon, Dong-O/S-2137-2016; OI Jeon, Dong-O/0000-0001-6482-5878; KIM, SANG-HO/0000-0001-5190-9909; doleans, marc/0000-0003-4542-8724 NR 10 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 2002 VL 495 IS 2 BP 85 EP 94 AR PII S0168-9002(02)01576-0 DI 10.1016/S0168-9002(02)01576-0 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 622BY UT WOS:000179627700001 ER PT J AU Chouffani, K Wells, D Harmon, F Jones, J Lancaster, G AF Chouffani, K Wells, D Harmon, F Jones, J Lancaster, G TI Laser-Compton scattering from a 20 MeV electron beam SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE laser; Compton scattering; X-ray; linear accelerator ID HARD X-RAYS; RELATIVISTIC ELECTRONS; CHANNELING RADIATION; BACKSCATTERING; ANGIOGRAPHY; GENERATION; CRYSTALS AB Laser-Compton scattering (LCS) experiments were carried out at the Idaho Accelerator Center. A 20 MeV electron beam was brought to a head-on collision with a 100 MW 7 ns Nd:YAG laser. We observed clear narrow LCS X-ray spectral peaks resulting from the interaction of the electron beam with the two Nd:YAG laser photon lines of 1064 and 532 nm. The LCS X-ray energy lines and widths were measured as a function of the electron beam energy and energy spread, respectively. The results recorded showed good agreement with. the predicted values. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Idaho Accelerator Ctr, Pocatello, ID 83209 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Chouffani, K (reprint author), Idaho Accelerator Ctr, 1500 Alvin Riken Dr, Pocatello, ID 83209 USA. NR 29 TC 20 Z9 21 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 DEC 11 PY 2002 VL 495 IS 2 BP 95 EP 106 AR PII S0168-9002(02)01580-2 DI 10.1016/S0168-9002(02)01580-2 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 622BY UT WOS:000179627700002 ER PT J AU Selim, FA Wells, DP Harmon, JF Kwofie, J Spaulding, R Erickson, G Roney, T AF Selim, FA Wells, DP Harmon, JF Kwofie, J Spaulding, R Erickson, G Roney, T TI Bremsstrahlung-induced highly penetrating probes for nondestructive assay and defect analysis SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE X-ray fluorescence; positron annihilation; nuclear isomers; defects; chemical assay ID POSITRONS; RADIATION; FILMS AB Nondestructive assay and defect analysis probes based on bremsstrahlung-induced processes have been developed to identify elements and probe defects in large volume samples. Bremsstrahlung beams from (electron accelerators) with end-point energies both above and below neutron emission threshold have been used. Below neutron emission threshold these beams (from 6 MeV small pulsed linacs), which exhibit high penetration, create positrons via pair production inside the material and produce X-ray fluorescence (XRF) radiation. Chemical assays of heavy elements in thick samples up to 10 g/cm(2) thick are provided by energy dispersive XRF measurements. The pair-produced positrons annihilate within the material, thereby emitting 511 keV gamma radiation. Doppler broadening spectroscopy of the 511 keV radiation can be performed to characterize the material and measure defects in samples of any desired thickness. This technique has successfully measured induced strain due to tensile stress in steel samples of 0.64 cm thick. Bremsstrahlung beams above neutron emission threshold, from a 20 MeV pulsed electron linac, have also been used to produce residual nuclei in excited states via photonuclear reactions allowing the detection of heavy elements via their characteristic gamma-rays. This can be developed into a technique to trace some heavy metals in large rocks and soils for environmental applications. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Idaho State Univ, Idaho Accelerator Ctr, Pocatello, ID 83209 USA. Boise State Univ, Boise, ID 83725 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Selim, FA (reprint author), Idaho State Univ, Idaho Accelerator Ctr, Campus Box 8263, Pocatello, ID 83209 USA. RI Selim, Farida/N-8077-2016 NR 15 TC 19 Z9 19 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 2002 VL 495 IS 2 BP 154 EP 160 AR PII S0168-9002(02)01575-9 DI 10.1016/S0168-9002(02)01575-9 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 622BY UT WOS:000179627700008 ER PT J AU Stein, OR LaTray, DA AF Stein, OR LaTray, DA TI Experiments and modeling of head cut migration in stratified soils SO WATER RESOURCES RESEARCH LA English DT Article DE scour; erosion; rill; gully; knickpoint; free overfall ID CONCENTRATED FLOWS; SCOUR DOWNSTREAM; EROSION; ADVANCE; GROWTH; AREAS; RIVER; USA AB A two-dimensional model is developed to predict head cut migration rate for the specific case of a relatively erosion-resistant soil layer overlying a deep, relatively erosive base soil. For this geometry, head cut migration can occur as a series of discrete mass failures of the surface layer caused by undercutting in a plunge pool formed immediately downstream. The length scale of one failure episode is modeled as a cantilevered slab failing in bending. The timescale for each failure episode is controlled by the rate and geometry of base layer scour, which is modeled independently of cantilevered slab properties. An integration of the two model components for the case of steady flow and uniform soil properties predicts linear upstream head cut migration with time, occurring in discrete steps bounded by successive mass failure events. The model is calibrated and tested in a series of flume experiments representing ideal conditions of different initial geometries and flow conditions. Head cut migration occurred by the proposed mechanism in a nearly linear rate. Average error between the observed and predicted retreat rate is 40%, most of this error is attributable to prediction of the scour hole shape. C1 Montana State Univ, Dept Civil Engn, Bozeman, MT 59717 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Stein, OR (reprint author), Montana State Univ, Dept Civil Engn, Bozeman, MT 59717 USA. NR 38 TC 18 Z9 19 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 11 PY 2002 VL 38 IS 12 AR 1284 DI 10.1029/2001WR001166 PG 12 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 649BU UT WOS:000181187700002 ER PT J AU Chang, C Naulleau, P Anderson, E Rosfjord, K Attwood, D AF Chang, C Naulleau, P Anderson, E Rosfjord, K Attwood, D TI Diffractive optical elements based on Fourier optical techniques: a new class of optics for extreme ultraviolet and soft x-ray wavelengths SO APPLIED OPTICS LA English DT Article AB A diffractive optical element, based on Fourier optics techniques, for use in extreme ultraviolet/soft x-ray experiments has been fabricated and demonstrated. This diffractive optical element, when illuminated by a uniform plane wave, will produce two symmetric off-axis first-order foci suitable for interferometric experiments. The efficiency of this optical element and its use in direct interferometric determination of optical constants are also discussed. Its use in direct interferometric determination of optical constants is also referenced. Its use opens a new era in the use of sophisticated optical techniques at short wavelengths. (C) 2002 Optical Society of America. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. EM cnchang@lbl.gov NR 5 TC 16 Z9 17 U1 1 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD DEC 10 PY 2002 VL 41 IS 35 BP 7384 EP 7389 DI 10.1364/AO.41.007384 PG 6 WC Optics SC Optics GA 625FC UT WOS:000179805400002 PM 12502293 ER PT J AU Patience, J White, RJ Ghez, AM McCabe, C McLean, IS Larkin, JE Prato, L Kim, SS Lloyd, JP Liu, MC Graham, JR Macintosh, BA Gavel, DT Max, CE Bauman, BJ Olivier, SS Wizinowich, P Acton, DS AF Patience, J White, RJ Ghez, AM McCabe, C McLean, IS Larkin, JE Prato, L Kim, SS Lloyd, JP Liu, MC Graham, JR Macintosh, BA Gavel, DT Max, CE Bauman, BJ Olivier, SS Wizinowich, P Acton, DS TI Stellar companions to stars with planets SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : general; planetary systems; stars : individual (HD 114762, tau Bootis, 16 Cygni B); techniques : high angular resolution ID ADAPTIVE OPTICS SYSTEM; KECK-II-TELESCOPE; SUN-LIKE STARS; FORMING REGIONS; INFRARED CAMERA; ACCRETION DISK; BINARY-SYSTEMS; IMAGING SURVEY; BROWN DWARF; TAU-BOOTIS AB A combination of high-resolution and wide-field imaging reveals two binary stars and one triple star system among the sample of the first 11 stars with planets detected by radial velocity variations. High-resolution speckle or adaptive optics (AO) data probe subarcsecond scales down to the diffraction limit of the Keck 10 m or the Lick 3 m, and direct images or AO images are sensitive to a wider field, extending to 10" or 38", depending on the camera. One of the binary system-HD 114762 was not previously known to be a spatially resolved multiple system; additional data taken with the combination of Keck adaptive optics and NIRSPEC are used to characterize the new companion. The second binary system-tau Boo-was a known multiple with two conflicting orbital solutions; the current data will help constrain the discrepant estimates of periastron time and separation. Another target-16 Cyg B-was a known common proper motion binary, but the current data resolve a new third component, close to the wide companion 16 Cyg A. Both the HD 114762 and 16 Cyg B systems harbor planets in eccentric orbits, while the Boo binary contains an extremely close planet in a tidally circularized orbit. Although the sample is currently small, the proportion of binary systems is comparable to that measured in the field over a similar separation range. Incorporating the null result from another companion search project lowers the overall fraction of planets in binary systems, but the detections in our survey reveal that planets can form in binaries separated by less than 50 AU. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. CARA, WM Keck Observ, Kamuela, HI 96743 USA. Univ Calif Los Angeles, IGPP, Los Angeles, CA 90095 USA. RP Patience, J (reprint author), Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, L-413, Livermore, CA 94550 USA. RI Kim, Sungsoo/A-8601-2011; OI Kim, Sungsoo/0000-0002-5570-2160; Max, Claire/0000-0003-0682-5436 NR 63 TC 97 Z9 97 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 2002 VL 581 IS 1 BP 654 EP 665 DI 10.1086/342982 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 623AU UT WOS:000179681500048 ER PT J AU Moon, YJ Choe, GS Wang, HM Park, YD Gopalswamy, N Yang, G Yashiro, S AF Moon, YJ Choe, GS Wang, HM Park, YD Gopalswamy, N Yang, G Yashiro, S TI A statistical study of two classes of coronal mass ejections SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : coronal mass ejections ( CMEs); Sun : filaments; Sun : flares ID LASCO; ACCELERATION; SPEEDS; FLARES AB A comprehensive statistical study is performed to address the question of whether two classes of coronal mass ejections (CMEs) exist. A total of 3217 CME events observed by SOHO/LASCO in 1996 2000 have been analyzed. We have examined the distributions of CMEs according to speed and acceleration, respectively, and investigated the correlation between speed and acceleration of CMEs. This statistical analysis is conducted for two subsets containing those CMEs that show a temporal and spatial association either with GOES X-ray solar flares or with eruptive laments. We have found that CMEs associated with flares have a higher median speed than those associated with eruptive laments and that the median speed of CMEs associated with strong flares is higher than that of weak-flare-associated CMEs. The distribution of CME acceleration shows a conspicuous peak near zero, not only for the whole data set, but also for the two subsets associated either with solar flares or with eruptive laments. However, we have confirmed that the CMEs associated with major flares tend to be more decelerated than the CMEs related to eruptive laments. The fraction of flare-associated CMEs has a tendency to increase with the CME speed, whereas the fraction of eruptive-filament associated CMEs tends to decrease with the CME speed. This result supports the concept of two CME classes. We have found a possibility of two components in the CME speed distribution for both the CME data associated with flares larger than M1 class and the CME data related with limb flares. Our results suggest that the apparent single-peak distribution of CME speed can be attributed to the projection effect and possibly to abundance of small flares too. We also note that there is a possible correlation between the speed of CMEs and the time-integrated X-ray flux of the CME-associated limb flares. C1 NJIT, Big Bear Solar Observ, Big Bear City, CA 92314 USA. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Catholic Univ Amer, Ctr Solar Phys & Space Weather, Washington, DC 20064 USA. RP Moon, YJ (reprint author), NJIT, Big Bear Solar Observ, 40386 N Shore Lane, Big Bear City, CA 92314 USA. RI Gopalswamy, Nat/D-3659-2012; Moon, Yong-Jae/E-1711-2013; Choe, Gwangson/E-2366-2013; OI Gopalswamy, Nat/0000-0001-5894-9954 NR 25 TC 119 Z9 125 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 DEC 10 PY 2002 VL 581 IS 1 BP 694 EP 702 DI 10.1086/344088 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 623AU UT WOS:000179681500051 ER PT J AU Sivaramakrishnan, A Lloyd, JP Hodge, PE Macintosh, BA AF Sivaramakrishnan, A Lloyd, JP Hodge, PE Macintosh, BA TI Speckle decorrelation and dynamic range in speckle noise-limited imaging SO ASTROPHYSICAL JOURNAL LA English DT Article DE instrumentation : adaptive optics; methods : analytical; methods : numerical; space vehicles : instruments; techniques : image processing ID ADAPTIVE OPTICS; EXTRASOLAR PLANETS; DARK SPECKLES; EXO-PLANETS; CORONAGRAPHY AB The useful dynamic range of an image in the diffraction-limited regime is usually limited by speckles caused by residual phase errors in the optical system forming the image. The technique of speckle decorrelation involves introducing many independent realizations of additional phase error into a wave front during one speckle lifetime, changing the instantaneous speckle pattern. A commonly held assumption is that this results in the speckles being "moved around" at the rate at which the additional phase screens are applied. The intention of this exercise is to smooth the speckles out into a more uniform background distribution during their persistence time, thereby enabling companion detection around bright stars to be photon noise limited rather than speckle limited. We demonstrate analytically why this does not occur and confirm this result with numerical simulations. We show that the original speckles must persist and that the technique of speckle decorrelation merely adds more noise to the original speckle noise, thereby degrading the dynamic range of the image. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP Sivaramakrishnan, A (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. NR 14 TC 67 Z9 68 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 2002 VL 581 IS 1 BP L59 EP L62 DI 10.1086/345826 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 623BB UT WOS:000179682200014 ER PT J AU Trudolyubov, SP Borozdin, KN Priedhorsky, WC Osborne, JP Watson, MG Mason, KO Cordova, FA AF Trudolyubov, SP Borozdin, KN Priedhorsky, WC Osborne, JP Watson, MG Mason, KO Cordova, FA TI The discovery of a 2.78 hour periodic modulation of the X-ray flux from globular cluster source Bo 158 in M31 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (M31); galaxies : star clusters; stars : individual (Bo 158); X-rays : stars ID PHOTON IMAGING CAMERA; XMM-NEWTON; CENTRAL REGION; HARD TAIL; M-31; ABSORPTION; INTENSITY; BINARIES; SPECTRUM; DIPS AB We report the discovery of periodic intensity dips in the X-ray source XMMU J004314.1+410724, in the globular cluster Bo 158 in M31. The X-ray flux was modulated by similar to83% at a period of 2.78 hr (10,017 s) in an XMM-Newton observation taken 2002 January 6-7. The X-ray intensity dips show no energy dependence. We detected weaker dips with the same period in observations taken 2000 June 25 (XMM-Newton) and 1991 June 26 (ROSAT/PSPC). The amplitude of the modulation has been found to be anticorrelated with source X-ray flux: it becomes lower when the source intensity rises. The energy spectrum of Bo 158 was stable from observation to observation, with a characteristic cutoff at similar to4-6 keV. The photoelectric absorption was consistent with the Galactic foreground value. No significant spectral changes were seen in the course of the dips. If the 2.78 hr cycle is the binary period of Bo 158, the system is highly compact, with a binary separation of similar to10(11) cm. The association of the source with a globular cluster, together with spectral parameters consistent with Galactic neutron star sources, suggests that X-rays are emitted by an accreting neutron star. The properties of Bo 158 are somewhat reminiscent of the Galactic X-ray sources exhibiting diplike modulations. We discuss two possible mechanisms explaining the energy-independent modulation observed in Bo 158: (1) the obscuration of the central source by highly ionized material that scatters X-rays out of the line of sight and (2) the partial covering of an extended source by an opaque absorber that occults varying fractions of the source. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Russian Acad Sci, Space Res Inst, Moscow 117810, Russia. RP Trudolyubov, SP (reprint author), Los Alamos Natl Lab, POB 1663,Mail Stop D436,NIS-2, Los Alamos, NM 87545 USA. OI Priedhorsky, William/0000-0003-0295-9138 NR 24 TC 22 Z9 22 U1 0 U2 1 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 DEC 10 PY 2002 VL 581 IS 1 BP L27 EP L31 DI 10.1086/345786 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 623BB UT WOS:000179682200007 ER PT J AU Smith, JD DeSain, JD Taatjes, CA AF Smith, JD DeSain, JD Taatjes, CA TI Infrared laser absorption measurements of HCl(upsilon=1) production in reactions of Cl atoms with isobutane, methanol, acetaldehyde, and toluene at 295 K SO CHEMICAL PHYSICS LETTERS LA English DT Article ID BOND-DISSOCIATION ENERGIES; RATE COEFFICIENTS; ELIMINATION-REACTIONS; CHEMICAL-DYNAMICS; CHLORINE ATOMS; HCL PRODUCTION; GAS-PHASE; ABSTRACTION; CHEMISTRY; CHEMILUMINESCENCE AB Absolute rate coefficients and branching ratios for production of HCl(v = 1) are measured for the reactions of Cl with (CH3)(3)CH, CH3OH, CH3CHO, and C6H5CH3. The fractions of HCl(v = 1) produced (f = HCl(v = 1)/HCl (total)) are f ((CH3)(3)CH) = 0.03 +/- 0.02, f (CH3OH) = 0.12 +/- 0.02, f (CH3CHO) = 0.54 +/- 0.04, and f(C6H5CH3) = 0.47 +/- 0.03; a significant fraction of the exothermicity appears in HCl vibration. Rate coefficients at 295 K are k((CH3)(3)CH) (1.49 +/- 0.02) x 10(-11), k(CH3OH) = (5.6 +/- 0.2) x 10(-11), k(CH3CHO) = (8.3 +/- 0.1) x 10(-11), and k(C6H5CH3) (6.1 +/- 0.2) x 10-11 cm(3) molecule(-1) s(-1). (C) 2002 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Taatjes, CA (reprint author), Sandia Natl Labs, Combust Res Facil, MS 9055, Livermore, CA 94551 USA. NR 35 TC 19 Z9 19 U1 0 U2 8 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 DEC 10 PY 2002 VL 366 IS 3-4 BP 417 EP 425 AR PII S0009-2614(02)01621-4 DI 10.1016/S0009-2614(02)01621-4 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 616YX UT WOS:000179332400034 ER PT J AU Sessler, JL Gorden, AEV Seidel, D Hannah, S Lynch, V Gordon, PL Donohoe, RJ Tait, CD Keogh, DW AF Sessler, JL Gorden, AEV Seidel, D Hannah, S Lynch, V Gordon, PL Donohoe, RJ Tait, CD Keogh, DW TI Characterization of the interactions between neptunyl and plutonyl cations and expanded porphyrins SO INORGANICA CHIMICA ACTA LA English DT Article DE actinides; macrocyclic ligand complexes; macrocycles; porphyrins; plutonium; neptunium ID CENTERED TEMPLATE REACTIONS; X-RAY CHARACTERIZATION; CROWN ETHER COMPLEXES; STRUCTURAL CHARACTERIZATION; TRIVALENT URANIUM; EXTRACTION PROPERTIES; URANYL COMPLEX; CHEMISTRY; ION; DERIVATIVES AB The synthesis of a new hexapyrrolic expanded porphyrin, hexaphyrin (1.0.1.0.0.0) (1), that was found to form unique complexes of the actinide cations neptunyl (NpO2+) and uranyl (UO22+) was recently reported (Sessler et al., Angew. Chem.. Int. Ed. Engl. 40 (2001) 591). The present study was undertaken in an effort to generalize these findings and involves an analysis of the neptanyl (NpO2+) and plutonyl, (PuO2+) coordination chemistry of several other expanded porphyrin systems. including those previously reported as having formed uranyl (UO22+) cation complexes, in particular amethyrin ([24]hexaphyrin(1.0.0. 1.0.0), 2), pentaphyrin, ([22]pentaphyrin(1.1.1.1.1), 4), and the Schiff base macrocycle, alaskaphyrin (5). This study was broadened to include the Schiff base ligand 6 (grandephyrin) and its previously unreported uranyl (UO22+) complex. Within moments of addition of a neptunium(VI) source to methanol solutions of the expanded porphyrins 1, 2, 4, 5 and 6, dramatic changes in the UV-Vis spectra are observed that are consistent with formation of a neptunyl complex and, in several cases, oxidation of the macrocycle. Similar changes were also observed when hexaphyrin (1), pentaphyrin (4), alaskaphyrin (5), and grandephyrin (6) were exposed to PuO22+. Corroborative changes are also observed in the associated H-1 NMR spectra and in those portions of the electronic spectrum associated with the actinide cations. Although the formation of the proposed neptunyl and plutonyl complexes could not be substantiated by X-ray diffraction methods, the solid-state structure of the uranyl complex formed from 6 was elucidated and is presented in this report. Published by Elsevier Science B.V. C1 Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA. Univ Texas, Inst Mol & Cellular Biol, Austin, TX 78712 USA. Los Alamos Natl Lab, Div Chem, GT Seaborg Inst Transactinium Sci, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Nucl Mat Technol, GT Seaborg Inst Transactinium Sci, Los Alamos, NM 87545 USA. RP Sessler, JL (reprint author), Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA. RI Gorden, Anne/D-2477-2011 OI Gorden, Anne/0000-0001-6623-9880 NR 56 TC 41 Z9 41 U1 1 U2 42 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0020-1693 J9 INORG CHIM ACTA JI Inorg. Chim. Acta PD DEC 10 PY 2002 VL 341 BP 54 EP 70 AR PII S0020-1693(02)01202-1 DI 10.1016/S0020-1693(02)01202-1 PG 17 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 624HP UT WOS:000179754500009 ER PT J AU Stevens, DE Chan, ST Gresho, P AF Stevens, DE Chan, ST Gresho, P TI An approximate projection method for incompressible flow SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS LA English DT Article ID NAVIER-STOKES EQUATIONS; FEM SOLUTIONS; MODEL; CURE AB This paper presents an approximate projection method for incompressible flows. This method is derived from Galerkin orthogonality conditions using equal-order piecewise linear elements for both velocity and pressure, hereafter Q1Q1. By combining an approximate projection for the velocities with a variational discretization of the continuum pressure Poisson equation, one eliminates the need to filter either the velocity or pressure fields as is often needed with equal-order element formulations. This variational approach extends to multiple types of elements; examples and results for triangular and quadrilateral elements are provided. This method is related to the method, of Almgren et al. (SIAM J. Sci. Comput. 2000; 22:1139-1159) and the PISO method of Issa (J Comput. Phys. 1985; 62:40-65). These methods use a combination of two elliptic solves, one to reduce the divergence of the velocities and another to approximate the pressure Poisson equation. Both Q1Q1 and the method of Almgren et al solve the second Poisson equation with a weak error tolerance to achieve more computational efficiency. A Fourier analysis of Q1Q1 shows that a consistent mass matrix has a positive effect on both accuracy and mass conservation. A numerical comparison with the widely used Q1Q0 (piecewise linear velocities, piecewise constant pressures) on a periodic test case with an analytic solution verifies this analysis. Q1Q1 is shown to have comparable accuracy as Q1Q0 and good agreement with experiment for flow over an isolated cubic obstacle and dispersion of a point source in its wake. Copyright (C) 2002 John Wiley Sons, Ltd. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Stevens, DE (reprint author), Lawrence Livermore Natl Lab, L-98,POB 808, Livermore, CA 94551 USA. NR 19 TC 2 Z9 2 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0271-2091 J9 INT J NUMER METH FL JI Int. J. Numer. Methods Fluids PD DEC 10 PY 2002 VL 40 IS 10 BP 1303 EP 1325 DI 10.1002/fld.419 PG 23 WC Computer Science, Interdisciplinary Applications; Mathematics, Interdisciplinary Applications; Mechanics; Physics, Fluids & Plasmas SC Computer Science; Mathematics; Mechanics; Physics GA 622KN UT WOS:000179646400003 ER PT J AU Vay, JL AF Vay, JL TI Asymmetric perfectly matched layer for the absorption of waves SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE perfectly matched layer; PML; absorbing boundary condition; ABC; finite-difference time domain; FDTD; wave equation; electromagnetics; Maxwell ID BOUNDARY-CONDITION; EQUATION AB The perfectly matched layer (PML) has become a standard for comparison in the techniques that have been developed to close the system of Maxwell equations (more generally, wave equations) when simulating an open system. The original Berenger PML formulation relies on a split version of Maxwell equations, with numerical electric and magnetic conductivities. We present here an extension of this formulation, which introduces counterparts of the electric and magnetic conductivities affecting the term which is spatially differentiated in the equations. The phase velocity along each direction is also multiplied by an additional coefficient. We show that under certain constraints on the additional numerical coefficients, this "medium" does not generate any reflection at any angle or any frequency and is thus a perfectly matched layer. Technically it is a superset of Berenger's PML to which it reduces for a specific set of parameters, and like it, it is anisotropic. However, unlike the PML, it introduces some asymmetry in the absorption rate and is therefore labeled an APML, for asymmetric perfectly matched layer. We present here the numerical considerations that have led us to introduce such a medium as well as its theory. Several finite-difference numerical implementations are derived (in one, two, and three dimensions) and the performance of the APML is contrasted with that of the PML in one and two dimensions. Using plane wave analysis, we show that our APML implementations lead to higher absorption rates than the considered PML implementations. Although we have considered in this paper the finite-difference discretization of Maxwell-like equations only, the APML system of equations may be used with other discretization schemes, such as finite elements, and may be applied to other equations, for applications beyond electromagnetics. (C) 2002 Elsevier Science (USA). C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Accelerator & Fus Res, Berkeley, CA 94720 USA. RP Vay, JL (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Accelerator & Fus Res, Berkeley, CA 94720 USA. NR 13 TC 13 Z9 14 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 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD DEC 10 PY 2002 VL 183 IS 2 BP 367 EP 399 DI 10.1006/jcph.2002.7175 PG 33 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 630MF UT WOS:000180111100002 ER PT J AU Ocko, BM Kelley, MS Nikova, AT Schwartz, DK AF Ocko, BM Kelley, MS Nikova, AT Schwartz, DK TI Structure and phase behavior of mixed monolayers of saturated and unsaturated fatty acids SO LANGMUIR LA English DT Article ID X-RAY-DIFFRACTION; BREWSTER-ANGLE MICROSCOPY; LANGMUIR MONOLAYERS; FLUORESCENCE MICROSCOPY; TRANSITIONS; DIAGRAMS; SURFACE; WATER; FILMS AB Grazing incidence X-ray diffraction (GIXD) and Brewster angle microscopy (BAM) were used to study the miscibility and phase behavior of Langmuir monolayers composed of a mixture of a saturated (stearic) and a trans-monounsaturated (elaidic) fatty acid. In contrast with suggestions from previous thermodynamic measurements, these compounds were poorly miscible in monolayers, and phase separation was always observed between domains of a liquid crystalline stearic acid-rich phase and a disordered elaidic acid-rich phase. The molecular packing density inside the ordered domains of mixed monolayers was within 2% of the density of pure stearic acid monolayers at the same surface pressure, suggesting that this phase contained at most a very small fraction of the larger elaidic acid molecules. However, the presence of this small concentration of unsaturated chains depressed the L-2 to Ov phase transition by similar to7 mN/m. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Tulane Univ, Dept Chem, New Orleans, LA 70118 USA. RP Ocko, BM (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Schwartz, Daniel/H-5153-2012; OI Kelley, Michael/0000-0002-6702-7676 NR 26 TC 16 Z9 16 U1 1 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 10 PY 2002 VL 18 IS 25 BP 9810 EP 9815 DI 10.1021/la026079y PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 623TU UT WOS:000179719600030 ER PT J AU Mallick, P Weiss, R Eisenberg, D AF Mallick, P Weiss, R Eisenberg, D TI The directional atomic solvation energy: An atom-based potential for the assignment of protein sequences to known folds SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID HIDDEN MARKOV-MODELS; 3-DIMENSIONAL STRUCTURE; SECONDARY STRUCTURE; PSI-BLAST; RECOGNITION; PROFILES; IDENTIFICATION; CONFORMATIONS; INFORMATION; PREDICTIONS AB The Directional Atomic Solvation EnergY (DASEY) is an atom-based description of the environment of an amino acid position within a known 3D protein structure. The DASEY has been developed to align and score a probe amino acid sequence to a library of template protein structures for fold assignment. DASEY is computed by summing the atomic solvation parameters of atoms failing within a tetrahedral sector, or petal, extending 16 A along each of the four bond axes of each a-carbon atom of the protein. The DASEY discriminates between pairs of structurally equivalent positions and random pairs in protein structures sharing a fold but belonging to different superfamilies, unlike some previous descriptors of protein environments, such as buried area. Furthermore, the DASEY values have characteristic patterns of residue replacement, an essential feature of a successful fold assignment method. Benchmarking fold assignment with DASEY achieves coverage of 56% of sequences with 90% accuracy when probe sequences are matched to protein structural templates belonging to the same fold but to a different superfamily, an improvement of greater than 200% over a previous method. C1 Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Howard Hughes Med Inst, Inst Mol Biol, DOE,Ctr Genomics & Prote, Los Angeles, CA 90095 USA. RP Eisenberg, D (reprint author), Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. NR 48 TC 21 Z9 24 U1 1 U2 3 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 DEC 10 PY 2002 VL 99 IS 25 BP 16041 EP 16046 DI 10.1073/pnas.252626399 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 624VY UT WOS:000179783400041 PM 12461172 ER PT J AU Fenimore, PW Frauenfelder, H McMahon, BH Parak, FG AF Fenimore, PW Frauenfelder, H McMahon, BH Parak, FG TI Slaving: Solvent fluctuations dominate protein dynamics and functions SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID X-RAY-DIFFRACTION; LIGAND-BINDING; CONFORMATIONAL DYNAMICS; CARBONMONOXY-MYOGLOBIN; ENERGY LANDSCAPE; MOSSBAUER-SPECTROSCOPY; DIELECTRIC-RELAXATION; HORSE MYOGLOBIN; ENZYME-ACTIVITY; CYTOCHROME-C AB Protein motions are essential for function. Comparing protein processes with the dielectric fluctuations of the surrounding solvent shows that they fall into two classes: nonslaved and slaved. Nonslaved processes are independent of the solvent motions; their rates are determined by the protein conformation and vibrational dynamics. Slaved processes are tightly coupled to the solvent; their rates have approximately the same temperature dependence as the rate of the solvent fluctuations, but they are smaller. Because the temperature dependence is determined by the activation enthalpy, we propose that the solvent is responsible for the activation enthalpy, whereas the protein and the hydration shell control the activation entropy through the energy landscape. Bond formation is the prototype of nonslaved processes; opening and closing of channels are quintessential slaved motions. The prevalence of slaved motions highlights the importance of the environment in cells and membranes for the function of proteins. C1 Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Theoret Biophys Grp, Los Alamos, NM 87545 USA. Tech Univ Munich, Fac Phys, D-85747 Garching, Germany. RP Frauenfelder, H (reprint author), Los Alamos Natl Lab, Ctr Nonlinear Studies, MS B258, Los Alamos, NM 87545 USA. NR 67 TC 417 Z9 418 U1 2 U2 61 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 DEC 10 PY 2002 VL 99 IS 25 BP 16047 EP 16051 DI 10.1073/pnas.212637899 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 624VY UT WOS:000179783400042 PM 12444262 ER PT J AU van Gastel, R Somfai, E van Albada, SB van Saarloos, W Frenken, JWM AF van Gastel, R Somfai, E van Albada, SB van Saarloos, W Frenken, JWM TI Vacancy diffusion in the Cu(001) surface I: an STM study SO SURFACE SCIENCE LA English DT Article DE scanning tunneling microscopy; surface diffusion; copper; indium; surface defects ID SCANNING-TUNNELING-MICROSCOPY; ATOMIC MECHANISMS; TERRACE DIFFUSION; CU(100) SURFACE; BROWNIAN-MOTION; ALLOY FORMATION; METAL-SURFACES; SELF-DIFFUSION; STEP DYNAMICS; AG(111) AB We have used the indium/copper surface alloy to study the dynamics of surface vacancies on the Cu(001) surface. Individual indium atoms that are embedded within the first layer of the crystal, are used as probes to detect the rapid diffusion of surface vacancies. STM measurements show that these indium atoms make multi-lattice-spacing jumps separated by long time intervals. Temperature dependent waiting time distributions show that the creation and diffusion of thermal vacancies form an Arrhenius type process with individual long jumps being caused by one vacancy only. The length of the long jumps is shown to depend on the specific location of the indium atom and is directly related to the lifetime of vacancies at these sites on the surface. This observation is used to expose the role of step edges as emitting and absorbing boundaries for vacancies. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Leiden Univ, Kamerlingh Onnes Lab, NL-2300 RA Leiden, Netherlands. Leiden Univ, Inst Lorentz, NL-2300 RA Leiden, Netherlands. RP van Gastel, R (reprint author), Sandia Natl Labs, Surface & Interface Sci Dept, POB 5800,Mail Stop 1415, Albuquerque, NM 87185 USA. RI Somfai, Ellak/A-9277-2009 OI Somfai, Ellak/0000-0002-2218-8855 NR 36 TC 37 Z9 37 U1 1 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 DEC 10 PY 2002 VL 521 IS 1-2 BP 10 EP 25 AR PII S0039-6028(02)02250-1 DI 10.1016/S0039-6028(02)02250-1 PG 16 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 621CQ UT WOS:000179571300007 ER PT J AU Somfai, E van Gastel, R van Albada, SB van Saarloos, W Frenken, JWM AF Somfai, E van Gastel, R van Albada, SB van Saarloos, W Frenken, JWM TI Vacancy diffusion in the Cu(001) surface II: Random walk theory SO SURFACE SCIENCE LA English DT Article DE surface diffusion; copper; indium ID ATOMIC SLIDE-PUZZLE; TRACER PARTICLE; LATTICE GAS; METALS AB We develop a version of the vacancy mediated tracer diffusion model, which follows the properties of the physical system of In atoms diffusing within the top layer of Cu(001) terraces. This model differs from the classical tracer diffusion problem in that (i) the lattice is finite, (ii) the boundary is a trap for the vacancy, and (iii) the diffusion rate of the vacancy is different, in our case strongly enhanced, in the neighborhood of the tracer atom. A simple continuum solution is formulated for this problem, which together with the numerical solution of the discrete model compares well with our experimental results. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Leiden Univ, Inst Lorentz, NL-2300 RA Leiden, Netherlands. Leiden Univ, Kamerlingh Onnes Lab, NL-2300 RA Leiden, Netherlands. RP Somfai, E (reprint author), Sandia Natl Labs, Dept Surface & Interface Sci, POB 5800,Mail Stop, Albuquerque, NM 87185 USA. RI Somfai, Ellak/A-9277-2009 OI Somfai, Ellak/0000-0002-2218-8855 NR 10 TC 23 Z9 24 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD DEC 10 PY 2002 VL 521 IS 1-2 BP 26 EP 33 AR PII S0039-6028(02)02251-3 DI 10.1016/S0039-6028(02)02251-3 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 621CQ UT WOS:000179571300008 ER PT J AU Jenks, CJ Ross, AR Lograsso, TA Whaley, JA Bastasz, R AF Jenks, CJ Ross, AR Lograsso, TA Whaley, JA Bastasz, R TI Angle-resolved low-energy ion scattering studies of quasicrystalline Al-Pd-Mn SO SURFACE SCIENCE LA English DT Article DE low energy ion scattering (LEIS); aluminum; palladium; manganese; surface structure; morphology; roughness and topography ID TRANSITION-METAL ALLOYS; 5-FOLD PLANE SURFACE; X-RAY-DIFFRACTION; QUASI-CRYSTAL; ELECTRON DIFFRACTION; ICOSAHEDRAL PHASE; FIVEFOLD SURFACE; ALPDMN; AL70PD21MN9; SEGREGATION AB We present angle-resolved low-energy ion scattering data that provide information about the composition of the topmost surface layers and atomic arrangement for a clean, 5-fold surface of a single-grain of icosahedral Al-Pd-Mn. The results show that the surface of this material has 5-fold periodicity and has a surface composition with a higher Al content than the bulk material (Al-86, Pd-13, Mn-1 versus Al-71, Pd-20, Mn-9 atom%). A predominant neighbor atom distance of 7.6 +/- 0.5 Angstrom is calculated from the results, consistent with scanning probe measurements and bulk models of Al Pd-Mn quasicrystals. We calculate a nearest neighbor distance of 3.0 +/- 0.2 Angstrom. We also find that a Pd-rich layer exists just below an Al-rich outer layer, in agreement with dynamical low-energy electron diffraction calculations. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Iowa State Univ, Dept Chem, Ames, IA 50011 USA. EM cjenks@iastate.edu NR 48 TC 19 Z9 19 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 EI 1879-2758 J9 SURF SCI JI Surf. Sci. PD DEC 10 PY 2002 VL 521 IS 1-2 BP 34 EP 42 AR PII S0039-6028(02)02276-8 DI 10.1016/S0039-6028(02)02276-8 PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 621CQ UT WOS:000179571300009 ER PT J AU Heske, C Groh, U Weinhardt, L Fuchs, O Holder, B Umbach, E Bostedt, C Terminello, LJ Zweigart, S Niesen, TP Karg, F AF Heske, C Groh, U Weinhardt, L Fuchs, O Holder, B Umbach, E Bostedt, C Terminello, LJ Zweigart, S Niesen, TP Karg, F TI Damp-heat induced sulfate formation in Cu(In,Ga)(S,Se)(2)-based thin film solar cells SO APPLIED PHYSICS LETTERS LA English DT Article ID X-RAY FLUORESCENCE; HETEROJUNCTION; SPECTROSCOPY; MODULES AB To investigate the impact of damp heat treatments on the electronic and chemical structure of Cu(In,Ga)(S,Se)(2)-based thin film solar cells, we have performed a detailed soft x-ray emission study of the ZnO/CuIn(S,Se)(2) and ZnO/CdS/CuIn(S,Se)(2) interfaces. By comparing the sulfur L-2,L-3 emission spectra of pristine and damp-heat treated samples, we find a sulfate formation at the ZnO/CuIn(S,Se)(2) and the ZnO/CdS interface. The intensity behavior as a function of ZnO film thickness further reveals a diffusion of sulfur atoms into the ZnO film, leading to the formation of zinc sulfate in the ZnO window layer of damp-heat-treated Cu(In,Ga)(S,Se)(2)-based solar cells. (C) 2002 American Institute of Physics. C1 Univ Wurzburg, D-97074 Wurzburg, Germany. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Shell Solar GmbH, D-81739 Munich, Germany. RP Heske, C (reprint author), Univ Wurzburg, D-97074 Wurzburg, Germany. RI Weinhardt, Lothar/G-1689-2013 NR 14 TC 19 Z9 19 U1 1 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 DEC 9 PY 2002 VL 81 IS 24 BP 4550 EP 4552 DI 10.1063/1.1525884 PG 3 WC Physics, Applied SC Physics GA 621VM UT WOS:000179611800018 ER PT J AU Jia, QX Foltyn, SR Arendt, PN Groves, JR Holesinger, TG Hawley, ME Lu, P AF Jia, QX Foltyn, SR Arendt, PN Groves, JR Holesinger, TG Hawley, ME Lu, P TI Role of SrRuO3 buffer layers on the superconducting properties of YBa2Cu3O7 films grown on polycrystalline metal alloy using a biaxially oriented MgO template SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS; CONDUCTIVE SRRUO3; ELECTRODES; DEPOSITION AB A SrRuO3 (SRO) buffer layer has been developed for growth of superconducting YBa2Cu3O7 (YBCO) thick films on polycrystalline metal substrates where a biaxially oriented MgO layer-produced by ion-beam-assisted deposition (IBAD)-was used as a template. By using such an architecture, we have routinely deposited YBCO films with an in-plane mosaic spread in the range of 3degrees-6degrees in full width at half maximum. A critical current density of 3.0x10(6) A/cm(2) in self-field at 75 K for a film thickness of over 1.3 mum has been achieved. We believe that the SRO buffer layer plays a significant role in the much improved performance of YBCO conductors built on IBAD MgO. The features of SRO, such as good lattice match with both MgO and YBCO, excellent thermal stability in an oxidizing environment, and planarization of growing surface, make it the ideal choice as the buffer layer for high-performance superconductor coatings. (C) 2002 American Institute of Physics. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. New Mexico Inst Min & Technol, Dept Mat Sci & Engn, Socorro, NM 87801 USA. RP Jia, QX (reprint author), Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 12 TC 38 Z9 38 U1 0 U2 9 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 9 PY 2002 VL 81 IS 24 BP 4571 EP 4573 DI 10.1063/1.1527699 PG 3 WC Physics, Applied SC Physics GA 621VM UT WOS:000179611800025 ER PT J AU Savvate'ev, V Chen-Esterlit, Z Aylott, JW Choudhury, B Kim, CH Zou, L Friedl, JH Shinar, R Shinar, J Kopelman, R AF Savvate'ev, V Chen-Esterlit, Z Aylott, JW Choudhury, B Kim, CH Zou, L Friedl, JH Shinar, R Shinar, J Kopelman, R TI Integrated organic light-emitting device/fluorescence-based chemical sensors SO APPLIED PHYSICS LETTERS LA English DT Article ID OXYGEN; ELECTROLUMINESCENCE; LUMINESCENCE; DEVICES AB A fluorescent chemical sensor platform, integrating an organic light-emitting device (OLED) light-source with a fluorescent probe, is demonstrated for a subsecond-fast oxygen sensor. The integration results in strong light coupling and negligible heating of the sensor film or analyte. The potential in vivo operation of compact, stand-alone, battery-powered, OLED-based miniaturized sensor arrays for chemical and biological applications is discussed. (C) 2002 American Institute of Physics. C1 Iowa State Univ Sci & Technol, Ames Lab, US DOE, Dept Phys, Ames, IA 50011 USA. Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. Iowa State Univ Sci & Technol, Microelect Res Ctr, Ames, IA 50011 USA. RP Kopelman, R (reprint author), Iowa State Univ Sci & Technol, Ames Lab, US DOE, Dept Phys, Ames, IA 50011 USA. RI Aylott, Jonathan/D-2237-2009 OI Aylott, Jonathan/0000-0003-1520-5490 NR 24 TC 49 Z9 49 U1 1 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 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 9 PY 2002 VL 81 IS 24 BP 4652 EP 4654 DI 10.1063/1.1518154 PG 3 WC Physics, Applied SC Physics GA 621VM UT WOS:000179611800052 ER PT J AU Sattelberger, AP Robinson, JM Currier, RP AF Sattelberger, AP Robinson, JM Currier, RP TI Inadvertent production and explosion of liquid chlorine dioxide SO CHEMICAL & ENGINEERING NEWS LA English DT Letter C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sattelberger, AP (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0009-2347 J9 CHEM ENG NEWS JI Chem. Eng. News PD DEC 9 PY 2002 VL 80 IS 49 BP 4 EP 5 PG 2 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 624HV UT WOS:000179755000002 ER PT J AU Cicero, JA Dorgan, JR Janzen, J Garrett, J Runt, J Lin, JS AF Cicero, JA Dorgan, JR Janzen, J Garrett, J Runt, J Lin, JS TI Supramolecular morphology of two-step, melt-spun poly(lactic acid) fibers SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE fibers; melt; morphology ID POLY(L-LACTIC ACID); BIODEGRADABLE FIBERS; RESORBABLE MATERIALS AB Fibers of poly(lactic acid) produced by two-step melt spinning have been studied. The morphology is elucidated with respect to the thermal and mechanical properties of fibers produced at cold-draw ratios of 1-8. With atomic force microscopy and small-angle X-ray scattering, a fibrillar morphology is found, with microfibril diameters ranging from 30 to 60 nm. Shrinkage properties indicate that, with increasing draw ratio, the fibers undergo a transition from class 2 to class 1 within the classification proposed by Keller. A supramolecular model for the morphology of the fibers is presented that entails a highly oriented skin with a core consisting of microfibrils. The orientation of the crystalline blocks within the microfibrils is similar to what has been reported for nylon fibers. (C) 2002 Wiley Periodicals, Inc. C1 Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA. Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Dorgan, JR (reprint author), Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA. RI He, Yong/F-8752-2012 NR 26 TC 41 Z9 41 U1 2 U2 15 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD DEC 9 PY 2002 VL 86 IS 11 BP 2828 EP 2838 DI 10.1002/app.11267 PG 11 WC Polymer Science SC Polymer Science GA 603GU UT WOS:000178551300026 ER PT J AU Cicero, JA Dorgan, JR Garrett, J Runt, J Lin, JS AF Cicero, JA Dorgan, JR Garrett, J Runt, J Lin, JS TI Effects of molecular architecture on two-step, melt-spun poly(lactic acid) fibers SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE fibers; melt; morphology ID POLY(L-LACTIC ACID); BIODEGRADABLE FIBERS; RESORBABLE MATERIALS; POLYLACTIDE; RHEOLOGY AB Fibers of poly(lactic acid) (PLA) produced by two-step melt spinning have been studied. The PLA resins used contain a 96:04 ratio of L:D stereochemical centers; however, one of the materials is branched by a peroxide treatment. The thermal, mechanical, and morphological properties of the fibers are compared for the two different molecular architectures. In the branched material, at least some of the branches exceed the entanglement molecular weight. The branched material is accordingly characterized by greater shear and extensional viscosity than the linear material. Fiber properties are highly influenced by the draw ratio; both branched and linear materials reach a plateau of about 35% crystallinity. The branched polymer reaches the plateau at a lower draw ratio, and this is indicative of faster crystallization kinetics. Both materials shrink in boiling water, and the amount of shrinkage decreases with increasing draw ratio. At an intermediate draw ratio of 6, the branched material is characterized by significantly larger shrinkage. With small-angle X-ray scattering and atomic force microscopy, the morphology is found to be fibrillar. Microfibril diameters range from approximately 20 to 30 run and are almost identical for the two molecular architectures studied. (C) 2002 Wiley Periodicals, Inc. C1 Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA. Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Dorgan, JR (reprint author), Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA. RI He, Yong/F-8752-2012 NR 28 TC 49 Z9 51 U1 3 U2 18 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD DEC 9 PY 2002 VL 86 IS 11 BP 2839 EP 2846 DI 10.1002/app.11268 PG 8 WC Polymer Science SC Polymer Science GA 603GU UT WOS:000178551300027 ER PT J AU Anastasiou, C Melnikov, K AF Anastasiou, C Melnikov, K TI Higgs boson production at hadron colliders in NNLO QCD SO NUCLEAR PHYSICS B LA English DT Article ID INELASTIC STRUCTURE FUNCTIONS; DIFFERENTIAL-EQUATIONS METHOD; SINGLET WILSON OPERATORS; LOW-ENERGY THEOREMS; FREE GAUGE-THEORIES; LEADING ORDER; ANOMALOUS DIMENSION; VIRTUAL CORRECTIONS; FEYNMAN-INTEGRALS; PARTON DENSITIES AB We compute the total cross-section for direct Higgs boson production in hadron collisions at NNLO in perturbative QCD. A new technique which allows us to perform an algorithmic evaluation of inclusive phase-space integrals is introduced, based on the Cutkosky rules, integration by parts and the differential equation method for computing master integrals. Finally, we discuss the numerical impact of the O(alpha(2)(s)) QCD corrections to the Higgs boson production cross-section at the LHC and the Tevatron. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Anastasiou, C (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 53 TC 570 Z9 570 U1 1 U2 7 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 DEC 9 PY 2002 VL 646 IS 1-2 BP 220 EP 256 AR PII S0550-3213(02)00837-4 DI 10.1016/S0550-3213(02)00837-4 PG 37 WC Physics, Particles & Fields SC Physics GA 620VG UT WOS:000179552700010 ER PT J AU Wang, WD Ellern, A Guzei, IA Espenson, JH AF Wang, WD Ellern, A Guzei, IA Espenson, JH TI Preparation, properties, and reactions of five-coordinate Re(VII) dioxo and diimido complexes SO ORGANOMETALLICS LA English DT Article ID MAIN-GROUP ELEMENTS; TRANSITION-METALS; MULTIPLE BONDS; CONDENSATION-REACTIONS; ALKYLRHENIUM OXIDES; METHYLTRIOXORHENIUM(VII); RHENIUM AB The reactions of aliphatic and aromatic 1,2-diamines, diols, and dithiols with CH3ReO3 (1), {CH3Re(NAr)(2)O}(2) (2, Ar = 2,6-diisopropylphenyl), and {CH3Re(NAr)(2)S}(2) (3) have been studied. Two of the reaction products, [CH3Re(O)(2){1,2-(NH)(2)C6H4}](2){mu-1,2-(NH2)(2)C6H4} (4a') and CH3Re(NAr)(2)(SCH2CH2S) (5c), have been structurally characterized. The former is a binuclear species in which each rhenium is six-coordinate with a pseudo-octahedral structure. The bridging phenylenediamine ligand can be replaced by pyridine and its derivatives. Unlike the known catecholato complex CH3ReVII(O)(2)(1,2-O2C6H4)(Py), the Re-V-benzoquinonediimine resonance form contributes noticeably to the overall structure of 4a'. The five-coordinate diimido complex 5c does not interact with coordinating ligands such as pyridines. The initial reactions of 2 with catechol and ethylene glycol lead to CH3Re(NAr)(2)(1,2-O2C6H4) (5b') and CH3Re(NAr)(2)(OCH2CH2O) (5b), respectively. Further hydrolysis of 5b affords CH3Re(NAr)(O)(OCH2CH2O) (6b). Compound 3, a sulfur analogue of 2, condenses only with dithiols. The high reactivity of 2 is likely due to the presence of a four-coordinate monomeric form in solution and the formation of H2O with strong O-H bonds as a byproduct. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. EM espenson@iastate.edu NR 16 TC 3 Z9 3 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD DEC 9 PY 2002 VL 21 IS 25 BP 5576 EP 5582 DI 10.1021/om020184l PG 7 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 623RU UT WOS:000179717300015 ER PT J AU Amarian, M Auerbach, L Averett, T Berthot, J Bertin, P Bertozzi, W Black, T Brash, E Brown, D Burtin, E Calarco, JR Cates, GD Chai, Z Chen, JP Choi, S Chudakov, E Cisbani, E de Jager, CW Deur, A DiSalvo, R Dieterich, S Djawotho, P Finn, M Fissum, K Fonvieille, H Frullani, S Gao, H Gao, J Garibaldi, F Gasparian, A Gilad, S Gilman, R Glamazdin, A Glashausser, C Goldberg, E Gomez, J Gorbenko, V Hansen, JO Hersman, FW Holmes, R Huber, GM Hughes, EW Humensky, TB Incerti, S Iodice, M Jensen, S Jiang, X Jones, C Jones, GM Jones, M Jutier, C Ketikyan, A Kominis, I Korsch, W Kramer, K Kumar, KS Kumbartzki, G Kuss, M Lakuriqi, E Laveissiere, G Lerose, J Liang, M Liyanage, N Lolos, G Malov, S Marroncle, J McCormick, K McKeown, R Meziani, ZE Michaels, R Mitchell, J Papandreou, Z Pavlin, T Petratos, GG Pripstein, D Prout, D Ransome, R Roblin, Y Rowntree, D Rvachev, M Sabatie, F Saha, A Slifer, K Souder, PA Saito, T Strauch, S Suleiman, R Takahashi, K Teijiro, S Todor, L Tsubota, H Ueno, H Urciuoli, G Van der Meer, R Vernin, P Voskanian, H Wojtsekhowski, B Xiong, F Xu, W Yang, JC Zhang, B Zolnierczuk, P AF Amarian, M Auerbach, L Averett, T Berthot, J Bertin, P Bertozzi, W Black, T Brash, E Brown, D Burtin, E Calarco, JR Cates, GD Chai, Z Chen, JP Choi, S Chudakov, E Cisbani, E de Jager, CW Deur, A DiSalvo, R Dieterich, S Djawotho, P Finn, M Fissum, K Fonvieille, H Frullani, S Gao, H Gao, J Garibaldi, F Gasparian, A Gilad, S Gilman, R Glamazdin, A Glashausser, C Goldberg, E Gomez, J Gorbenko, V Hansen, JO Hersman, FW Holmes, R Huber, GM Hughes, EW Humensky, TB Incerti, S Iodice, M Jensen, S Jiang, X Jones, C Jones, GM Jones, M Jutier, C Ketikyan, A Kominis, I Korsch, W Kramer, K Kumar, KS Kumbartzki, G Kuss, M Lakuriqi, E Laveissiere, G Lerose, J Liang, M Liyanage, N Lolos, G Malov, S Marroncle, J McCormick, K McKeown, R Meziani, ZE Michaels, R Mitchell, J Papandreou, Z Pavlin, T Petratos, GG Pripstein, D Prout, D Ransome, R Roblin, Y Rowntree, D Rvachev, M Sabatie, F Saha, A Slifer, K Souder, PA Saito, T Strauch, S Suleiman, R Takahashi, K Teijiro, S Todor, L Tsubota, H Ueno, H Urciuoli, G Van der Meer, R Vernin, P Voskanian, H Wojtsekhowski, B Xiong, F Xu, W Yang, JC Zhang, B Zolnierczuk, P CA Jefferson Lab E94010 Collaboratio TI Q(2) evolution of the generalized Gerasimov-Drell-Hearn integral for the neutron using a He-3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID DEEP-INELASTIC SCATTERING; SPIN STRUCTURE FUNCTIONS; SUM-RULE; POLARIZED LEPTONS; NUCLEI AB We present data on the inclusive scattering of polarized electrons from a polarized He-3 target at energies from 0.862 to 5.06 GeV, obtained at a scattering angle of 15.5degrees. Our data include measurements from the quasielastic peak, through the nucleon resonance region, and beyond, and were used to determine the virtual photon cross-section difference sigma(1/2)-sigma(3/2). We extract the extended Gerasimov-Drell-Hearn integral for the neutron in the range of four-momentum transfer squared Q(2) of 0.1-0.9 GeV2. C1 Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. CALTECH, Pasadena, CA 91125 USA. Chungnam Natl Univ, Taejon 305764, South Korea. Hampton Univ, Hampton, VA 23668 USA. Univ Clermont Ferrand, CNRS, IN2P3, LPC, F-63170 Clermont Ferrand, France. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Kent State Univ, Kent, OH 44242 USA. Univ Kentucky, Lexington, KY 40506 USA. Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. Univ Maryland, College Pk, MD 20742 USA. MIT, Cambridge, MA 02139 USA. Univ Massachusetts, Amherst, MA 01003 USA. Univ New Hampshire, Durham, NH 03824 USA. Old Dominion Univ, Norfolk, VA 23529 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Regina, Regina, SK S4S 0A2, Canada. Rutgers State Univ, Piscataway, NJ 08855 USA. CEA Saclay, DAPNIA SPhN, F-91191 Gif Sur Yvette, France. Syracuse Univ, Syracuse, NY 13244 USA. Temple Univ, Philadelphia, PA 19122 USA. Tohoku Univ, Sendai, Miyagi 980, Japan. Univ Virginia, Charlottesville, VA 22904 USA. Coll William & Mary, Williamsburg, VA 23187 USA. Yerevan Phys Inst, Yerevan 375036, Armenia. RP Amarian, M (reprint author), Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. RI Kominis, Iannis/C-5515-2011; Averett, Todd/A-2969-2011; Gao, Haiyan/G-2589-2011; Kuss, Michael/H-8959-2012; Sabatie, Franck/K-9066-2015 OI Sabatie, Franck/0000-0001-7031-3975 NR 38 TC 85 Z9 86 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 DEC 9 PY 2002 VL 89 IS 24 AR 242301 DI 10.1103/PhysRevLett.89.242301 PG 6 WC Physics, Multidisciplinary SC Physics GA 619PG UT WOS:000179484700008 PM 12484938 ER PT J AU Bennett, GR Cuneo, ME Vesey, RA Porter, JL Adams, RG Aragon, RA Caird, JA Landen, OL Rambo, PK Rovang, DC Ruggles, LE Simpson, WW Smith, IC Wenger, DF AF Bennett, GR Cuneo, ME Vesey, RA Porter, JL Adams, RG Aragon, RA Caird, JA Landen, OL Rambo, PK Rovang, DC Ruggles, LE Simpson, WW Smith, IC Wenger, DF TI Symmetric inertial-confinement-fusion-capsule implosions in a double-Z-pinch-driven hohlraum SO PHYSICAL REVIEW LETTERS LA English DT Article ID RAY-IMAGING SYSTEMS; LASER; DESIGN AB An inertial-confinement-fusion (ICF) concept using two 60-MA Z pinches to drive a cylindrical hohlraum to 220 eV has been recently proposed. The first capsule implosions relevant to this concept have been performed at the same physical scale with a lower 20-MA current, yielding a 70+/-5 eV capsule drive. The capsule shell shape implies a polar radiation symmetry, the first high-accuracy measurement of this type in a pulsed-power-driven ICF configuration, within a factor of 1.6-4 of that required for scaling to ignition. The convergence ratio of 14-21 is to date the highest in any pulsed-power ICF system. C1 Ktech Corp Inc, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Bennett, GR (reprint author), Ktech Corp Inc, 2201 Buena Vista SE,Suite 400, Albuquerque, NM 87106 USA. NR 16 TC 41 Z9 41 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 DEC 9 PY 2002 VL 89 IS 24 AR 245002 DI 10.1103/PhysRevLett.89.245002 PG 4 WC Physics, Multidisciplinary SC Physics GA 619PG UT WOS:000179484700021 PM 12484951 ER PT J AU Fishman, RS Liu, SH AF Fishman, RS Liu, SH TI Local symmetry breaking by impurities and mode splitting in doped SmS SO PHYSICAL REVIEW LETTERS LA English DT Article ID VALENCE SEMICONDUCTORS; NEUTRON-SCATTERING; STATE; TRANSITION; SMB6 AB We introduce the idea of local symmetry breaking by impurities to explain the recently observed splitting of the J = 0 --> 1 propagating excitation in doped Sm1-xYxS. While preserving the global cubic symmetry of the crystal, Y impurities change the local crystal-field environment of each Sm ion from cubic to tetragonal, thereby splitting the J = 1 triplet into a m(i) . J = 0 level with energy Delta(1) and a m(i) . J = +/-1 doublet with energy Delta(2)>Delta(1). A model with a randomly oriented quantization axis m(i) fits not only the observed mode frequencies but also their intensities, which strongly depends on the wave vector. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Fishman, Randy/C-8639-2013 NR 21 TC 4 Z9 4 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 9 PY 2002 VL 89 IS 24 AR 247203 DI 10.1103/PhysRevLett.89.247203 PG 4 WC Physics, Multidisciplinary SC Physics GA 619PG UT WOS:000179484700049 PM 12484979 ER PT J AU Hayes, AB Cline, D Wu, CY Simon, MW Teng, R Gerl, J Schlegel, C Wollersheim, HJ Macchiavelli, AO Vetter, K Napiorkowski, P Srebrny, J AF Hayes, AB Cline, D Wu, CY Simon, MW Teng, R Gerl, J Schlegel, C Wollersheim, HJ Macchiavelli, AO Vetter, K Napiorkowski, P Srebrny, J TI Coulomb excitation paths of high-K isomer bands in Hf-178 SO PHYSICAL REVIEW LETTERS LA English DT Article ID ROTATIONAL BAND; STATES AB Three distinctly different mechanisms are shown to populate the K-pi=6(+) (t(1/2)=77 ns), 16(+) (31 yr), and 8(-) (4 s) isomer bands of Hf-178 by Coulomb excitation. High spin states of the three isomer bands were populated by Coulomb excitation of a hafnium target with a 650 MeV Xe-136 beam. Although direct population of high-K bands is highly K-forbidden, isomer bands in Hf-178 were populated up to spins 13(K=6)(+), 20(K=16)(+), and 14(K=8)(-) with in-band gamma yields of similar to10(-4) of the ground state band. The data are consistent with a rapid increase in K mixing with increasing spin in the isomer bands. C1 Univ Rochester, Dept Phys, Nucl Struct Res Lab, Rochester, NY 14627 USA. Gesell Schwerionenforsch mbH, GSI, D-64291 Darmstadt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Warsaw Univ, Heavy Ion Lab, Warsaw, Poland. Warsaw Univ, Inst Expt Phys, Warsaw, Poland. RP Hayes, AB (reprint author), Univ Rochester, Dept Phys, Nucl Struct Res Lab, 601 Elmwood Ave, Rochester, NY 14627 USA. RI Gerl, Juergen/A-3255-2011 NR 22 TC 26 Z9 29 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 DEC 9 PY 2002 VL 89 IS 24 AR 242501 DI 10.1103/PhysRevLett.89.242501 PG 4 WC Physics, Multidisciplinary SC Physics GA 619PG UT WOS:000179484700009 PM 12484939 ER PT J AU Kolesnichenko, YI Lutsenko, VV Marchenko, VS White, RB AF Kolesnichenko, YI Lutsenko, VV Marchenko, VS White, RB TI Effect of trapped energetic ions on MHD activity in spherical tori SO PHYSICS LETTERS A LA English DT Article ID FISHBONE MODE; INTERNAL KINK; TOKAMAKS; STABILIZATION; TRANSPORT; SAWTEETH; PLASMAS AB It is shown that the increase of beta (the ratio of plasma pressure to the magnetic field pressure) may change the character of the influence of trapped energetic ions on MHD stability in spherical tori. Namely, the energetic ions, which stabilize MHD modes (such as the ideal kink mode, collisionless tearing mode and semi-collisional tearing mode) at low beta, have a destabilizing influence at high beta unless the radial distribution of the energetic ions is very peaked. (C) 2002 Elsevier Science B.V All rights reserved. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Natl Acad Sci Ukraine, Nucl Res Inst, UA-03680 Kiev, Ukraine. RP White, RB (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 16 TC 1 Z9 1 U1 0 U2 4 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 DEC 9 PY 2002 VL 305 IS 5 BP 245 EP 250 AR PII S0375-9601(02)01451-2 DI 10.1016/S0375-9601(02)01451-2 PG 6 WC Physics, Multidisciplinary SC Physics GA 624YU UT WOS:000179790500006 ER PT J AU Frischknecht, AL Weinhold, JD Salinger, AG Curro, JG Frink, LJD McCoy, JD AF Frischknecht, AL Weinhold, JD Salinger, AG Curro, JG Frink, LJD McCoy, JD TI Density functional theory for inhomogeneous polymer systems. I. Numerical methods SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SELF-CONSISTENT-FIELD; THERMODYNAMIC PERTURBATION-THEORY; SYMMETRICAL DIBLOCK COPOLYMERS; NONUNIFORM POLYATOMIC SYSTEMS; INTEGRAL-EQUATION THEORY; STATE ALKANE MELT; MICROPHASE SEPARATION; SLIT PORE; HARD-WALL; IMMISCIBLE POLYMERS AB We present a new real space Newton-based computational approach to computing the properties of inhomogeneous polymer systems with density functional theory (DFT). The DFT is made computationally efficient by modeling the polymers as freely jointed chains and obtaining direct correlation functions from polymer reference interaction site model calculations. The code we present can solve the DFT equations in up to three dimensions using a parallel implementation. In addition we describe our implementation of an arc-length continuation algorithm, which allows us to explore the phase space of possible solutions to the DFT equations. These numerical tools are applied in this paper to hard chains near hard walls and briefly to block copolymer systems. The method is shown to be accurate and efficient. Arc-length continuation calculations of the diblock copolymer systems illustrate the care required to obtain a complete understanding of the structures that may be found with this polymer-DFT approach. (C) 2002 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. New Mexico Inst Min & Technol, Dept Mat & Met Engn, Socorro, NM 87801 USA. RP Frischknecht, AL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI McCoy, John/B-3846-2010; Frischknecht, Amalie/N-1020-2014 OI McCoy, John/0000-0001-5404-1404; Frischknecht, Amalie/0000-0003-2112-2587 NR 72 TC 36 Z9 36 U1 0 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 2002 VL 117 IS 22 BP 10385 EP 10397 DI 10.1063/1.1518685 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 617BP UT WOS:000179340600050 ER PT J AU Frischknecht, AL Curro, JG Frink, LJD AF Frischknecht, AL Curro, JG Frink, LJD TI Density functional theory for inhomogeneous polymer systems. II. Application to block copolymer thin films SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SELF-CONSISTENT-FIELD; MONTE-CARLO SIMULATIONS; SYMMETRICAL DIBLOCK COPOLYMERS; NONUNIFORM POLYATOMIC SYSTEMS; SURFACE-INDUCED ORIENTATION; MICROPHASE SEPARATION; PHASE-TRANSITIONS; MICROSCOPIC APPROACH; MELTS; THERMODYNAMICS AB We use polymer reference interaction site model (PRISM)-based density functional theory (DFT) to study the structures and morphologies of block copolymer thin films. The polymers are modeled as freely jointed chains, allowing numerical solution of the nonlinear DFT equations. The use of PRISM with DFT allows the inclusion of compressibility and local packing effects due to the finite size of the monomers. We also employ a pseudo-arclength continuation algorithm to locate phase transitions and new morphologies. We study symmetric diblock copolymers confined between two parallel surfaces which both attract one component of the diblock, for two different values of AB segregation strength and for various surface interactions. The predicted equilibrium morphologies are in good qualitative agreement with previous self-consistent field calculations and are consistent with experiment. We are able to resolve the detailed packing structure near the surfaces. We find that packing effects enhance the stability of the perpendicular morphologies. (C) 2002 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Frischknecht, AL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Frischknecht, Amalie/N-1020-2014 OI Frischknecht, Amalie/0000-0003-2112-2587 NR 46 TC 47 Z9 47 U1 0 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 2002 VL 117 IS 22 BP 10398 EP 10411 DI 10.1063/1.1518686 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 617BP UT WOS:000179340600051 ER PT J AU Chalmers, G AF Chalmers, G TI Cosmological constant in broken maximal supergravities SO CLASSICAL AND QUANTUM GRAVITY LA English DT Letter ID YANG-MILLS THEORY; SUPERSYMMETRY; BREAKING AB We examine the form of the cosmological constant in the loop expansion of broken maximally supersymmetric supergravity theories, and after embedding, within superstring and M-theory. Supersymmetry breaking at the TeV scale generates values of the cosmological constant that are in agreement with current astrophysical data. The form of perturbative quantum effects in the loop expansion is consistent with this parameter regime. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Chalmers, G (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 17 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD DEC 7 PY 2002 VL 19 IS 23 BP L193 EP L198 AR PII S0264-9381(02)52335-2 DI 10.1088/0264-9381/19/23/101 PG 6 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 631ZC UT WOS:000180197300001 ER PT J AU Delsanto, PP Johnson, PA Scalerandi, M TenCate, JA AF Delsanto, PP Johnson, PA Scalerandi, M TenCate, JA TI LISA simulations of time-reversed acoustic and elastic wave experiments SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID CONNECTION MACHINE SIMULATION; FOURIER MIGRATION METHOD; ULTRASONIC PULSES; MULTIPLE-SCATTERING; SHALLOW-WATER; PROPAGATION; OPERATOR; GUIDE AB Several experiments in the last decade have demonstrated the enormous potential of time-reversed acoustic (TRA) and elastic (TRE) waves for applications in many fields, such as medicine, materials characterization and oceanography. In the present contribution, we demonstrate the applicability of the local interaction simulation approach (LISA) to simulate, by means of virtual experiments, both TRA and TRE and to reproduce the relevant features of both techniques. C1 Politecn Torino, Dipartimento Fis, INFM, I-10129 Turin, Italy. Los Alamos Natl Lab, Geophys Grp, Los Alamos, NM 87545 USA. RP Delsanto, PP (reprint author), Politecn Torino, Dipartimento Fis, INFM, Corso Duca Abruzzi 24, I-10129 Turin, Italy. OI SCALERANDI, MARCO/0000-0003-0809-9976 NR 26 TC 9 Z9 9 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD DEC 7 PY 2002 VL 35 IS 23 BP 3145 EP 3152 AR PII S0022-3727(02)36207-7 DI 10.1088/0022-3727/35/23/316 PG 8 WC Physics, Applied SC Physics GA 631PU UT WOS:000180176800016 ER PT J AU Glass, RJ Nicholl, MJ Pringle, SE Wood, TR AF Glass, RJ Nicholl, MJ Pringle, SE Wood, TR TI Unsaturated flow through a fracture-matrix network: Dynamic preferential pathways in mesoscale laboratory experiments SO WATER RESOURCES RESEARCH LA English DT Article DE preferential flow; fracture network; vadose zone; unsaturated flow ID POROUS-MEDIA; WATER-FLOW; PHYSICS; CHALK; ROCK AB [1] We conducted two laboratory experiments at the meter scale in which water was applied to the top of an initially dry, uncemented wall composed of porous bricks. One experiment (Experiment 1) encouraged evaporation and resulting mineral precipitation, while the other (Experiment 2) was designed to minimize these processes. In both cases, processes acting within the fracture network controlled early time behavior, forming discrete pathways and demonstrating fractures to act as both flow conductors and capillary barriers. At a later time, evaporation-mineral precipitation in Experiment 1 constrained flow, strengthening some pathways and starving others. In Experiment 2, the wetted structure took on the appearance of a diffuse plume; however, individual pathways persisted within the wetted structure and interacted, displaying erratic outflow over a wide range of timescales, including switching between pathways. Thus, under conditions of constant supply and both with and without evaporation-mineral precipitation, unsaturated flow through fractured rock can create dynamic preferential pathways. C1 Sandia Natl Labs, Geohyrol Dept, Flow Visualizat & Proc Lab, Albuquerque, NM 87185 USA. Univ Idaho, Dept Mat Met Min & Geol Engn, Moscow, ID 83843 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Glass, RJ (reprint author), Sandia Natl Labs, Geohyrol Dept, Flow Visualizat & Proc Lab, Mail Stop 0735, Albuquerque, NM 87185 USA. NR 20 TC 24 Z9 25 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 7 PY 2002 VL 38 IS 12 AR 1281 DI 10.1029/2001WR001002 PG 17 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 646EC UT WOS:000181021000002 ER PT J AU Baisden, WT Amundson, R Cook, AC Brenner, DL AF Baisden, WT Amundson, R Cook, AC Brenner, DL TI Turnover and storage of C and N in five density fractions from California annual grassland surface soils SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article DE soil organic matter turnover; density fractionation; radiocarbon; stable isotopes; decomposition ID ORGANIC-MATTER FRACTIONS; NMR-SPECTROSCOPY; CARBON; DYNAMICS; NITROGEN; CULTIVATION; FOREST; SEQUESTRATION; TILLAGE; RATES AB [1] We measured (14)C/(12)C in density fractions from soils collected before and after atmospheric thermonuclear weapons testing to examine soil organic matter (SOM) dynamics along a 3 million year California soil chronosequence. The mineral- free particulate organic matter (FPOM; <1.6 g cm(-3)) mainly contains recognizable plant material, fungal hyphae, and charcoal. Mineral- associated light fractions (1.6- 2. 2 g cm 3) display partially or completely humified fine POM, while the dense fraction (> 2.2 g cm(-3)) consists of relatively OM- free sand and OM- rich clays. Three indicators of decomposition (C: N, delta(13)C, and delta(15)N) all suggest increasing SOM decomposition with increasing fraction density. The Delta(14)C- derived SOM turnover rates suggest that greater than or equal to90% of FPOM turns over in <10 years. The four mineral- associated fractions contain 69- 86% " stabilized'' (decadal) SOM with the remainder assumed to be " passive'' (millenial) SOM. Within each soil, the four mineral- associated fractions display approximately the same residence time (34- 42 years in 200 kyr soil, 29- 37 years in 600 kyr soil, and 18- 26 years in 1- 3 Myr soils), indicating that a single stabilized SOM " pool'' exists in these soils and may turn over primarily as a result of soil disruption. C1 Univ Calif Berkeley, Dept ESPM, Ecosyst Sci Div, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. RP Baisden, WT (reprint author), Massey Univ, Campus,Private Bag 11052, Palmerston North, New Zealand. EM BaisdenT@landcare.cri.nz RI Baisden, Troy/B-9831-2008; Amundson, Ronald /E-2654-2015 OI Baisden, Troy/0000-0003-1814-1306; NR 53 TC 86 Z9 89 U1 4 U2 62 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD DEC 6 PY 2002 VL 16 IS 4 AR 1117 DI 10.1029/2001GB001822 PG 16 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 646YB UT WOS:000181062900001 ER PT J AU West, JM Tsuruta, H Kantrowitz, ER AF West, JM Tsuruta, H Kantrowitz, ER TI Stabilization of the R allosteric structure of Escherichia coli aspartate transcarbamoylase by disulfide bond formation SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID HETEROTROPIC INTERACTIONS; HOMOTROPIC COOPERATIVITY; QUATERNARY STRUCTURE; KINETIC MECHANISM; CATALYTIC CHAIN; DOMAIN CLOSURE; TRANSITION; CARBAMOYLTRANSFERASE; MODEL; CONSEQUENCES AB Here we report the first use of disulfide bond formation to stabilize the R allosteric structure of Escherichia coli aspartate transcarbamoylase. In the R allosteric state, residues in the 240s loop from two catalytic chains of different subunits are close together, whereas in the T allosteric state they are far apart. By substitution of Ala-241 in the 240s loop of the catalytic chain with cysteine, a disulfide bond was formed between two catalytic chains of different subunits. The cross-linked enzyme did not exhibit cooperativity for aspartate. The maximal velocity was increased, and the concentration of aspartate required to obtain one-half the maximal velocity, [Asp](0.5), was reduced substantially. Furthermore, the allosteric effectors ATP and CTP did not alter the activity of the cross-linked enzyme. When the disulfide bonds were reduced by the addition of 1,4-dithio-DL-threitol the resulting enzyme had kinetic parameters very similar to those observed for the wild-type enzyme and regained the ability to be activated by ATP and inhibited by CTP. Small-angle x-ray scattering was used to verify that the cross-linked enzyme was structurally locked in the R state and that this enzyme after reduction with 1,4-dithio-DL-threitol could undergo an allosteric transition similar to that of the wild-type enzyme. The complete abolition of homotropic and heterotropic regulation from stabilizing the 240s loop in its closed position in the R state, which forms the catalytically competent active site, demonstrates the significance that the quaternary structural change and closure of the 240s loop has in the functional mechanism of aspartate transcarbamoylase. C1 Boston Coll, Merkert Chem Ctr, Dept Chem, Chestnut Hill, MA 02467 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RP Kantrowitz, ER (reprint author), Boston Coll, Merkert Chem Ctr, Dept Chem, Chestnut Hill, MA 02467 USA. FU NCRR NIH HHS [P41RR01209]; NIGMS NIH HHS [GM26237] NR 40 TC 7 Z9 7 U1 0 U2 1 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 DEC 6 PY 2002 VL 277 IS 49 BP 47300 EP 47304 DI 10.1074/jbc.M209913200 PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 622TT UT WOS:000179663700060 PM 12359710 ER PT J AU He, Y Yeung, ES Chan, KC Issaq, HJ AF He, Y Yeung, ES Chan, KC Issaq, HJ TI Two dimensional mapping of cancer cell extracts by liquid chromatography-capillary electrophoresis with ultraviolet absorbance detection SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 15th international Symposium on Microscale Separations and Analysis (HPCE 2002) CY APR, 2002 CL STOCKHOLM, SWEDEN DE two-dimensional mapping; cancer cell extracts ID VOLUME SAMPLE STACKING; ZONE-ELECTROPHORESIS; PROTEINS; SEPARATION; PROTEOMICS; DRUGS AB A two-dimensional liquid chromatography/capillary electrophoresis technique was developed for rapid and comprehensive mapping of cell extracts. The cell extracts were first separated by reversed-phase HPLC based on hydrophobicity. Fractions of the effluent from the HPLC system were collected into 96-well microtiter plates and dried under vacuum. The fractions were reconstituted with deionized water, separated by capillary array electrophoresis based on charge-to-size ratio, and detected by UV absorption at 214 nm. Prior to analysis by multiplexed capillary electrophoresis, the reconstituted fractions were concentrated on-column using large volume sample stacking with polarity switching. In this way, high-resolution analysis of even the minor components in the complicated mixture was possible. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Ames Lab, USDOE, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. NCI Frederick, SAIC Frederick, Frederick, MD 21702 USA. RP Yeung, ES (reprint author), Iowa State Univ Sci & Technol, Ames Lab, USDOE, Ames, IA 50011 USA. FU NCI NIH HHS [N01-CO-12400] NR 21 TC 13 Z9 14 U1 1 U2 5 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 DEC 6 PY 2002 VL 979 IS 1-2 BP 81 EP 89 AR PII S0021-9673(02)01503-0 DI 10.1016/S0021-9673(02)01503-0 PG 9 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 618EX UT WOS:000179406700009 PM 12498235 ER PT J AU Kirby, BJ Shepodd, TJ Hasselbrink, EF AF Kirby, BJ Shepodd, TJ Hasselbrink, EF TI Voltage-addressable on/off microvalves for high-pressure microchip separations SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 15th international Symposium on Microscale Separations and Analysis (HPCE 2002) CY APR, 2002 CL STOCKHOLM, SWEDEN DE chip technology; instrumentation ID SOFT LITHOGRAPHY AB We present a microchip-based, voltage-addressable on/off valve architecture that is fundamentally consistent with the pressures and solvents employed for high-pressure liquid chromatography. Laser photopatterning of polymer monoliths inside glass microchannels is used to fabricate mobile fluid control elements, which are opened and closed by electrokinetic pressures. The glass substrates and crosslinked polymer monoliths operate in water-acetonitrile mixtures and have been shown to hold off pressures as high as 350 bar (5000 p.s.i.). Open/closed flow ratios of 104 to 106 have been demonstrated over the pressure range 1.5-70 bar (20-1000 p.s.i.), and the pressure-leak relationship shows the potential for valving control of flow through packed or monolithic chromatography columns. We expect that this valve platform will enable multiplexing of multiple chromatographic separations on single microchips. Published by Elsevier Science B.V. C1 Sandia Natl Labs, Microfluid Dept, Livermore, CA 94550 USA. RP Kirby, BJ (reprint author), Sandia Natl Labs, Microfluid Dept, POB 969,MS 9951, Livermore, CA 94550 USA. NR 10 TC 38 Z9 41 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 DEC 6 PY 2002 VL 979 IS 1-2 BP 147 EP 154 AR PII S0021-9673(02)01453-X DI 10.1016/S0021-9673(02)01453-X PG 8 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 618EX UT WOS:000179406700017 PM 12498243 ER PT J AU Sam, MD Papagiannis, CV Connolly, KM Corselli, L Iwahara, J Lee, J Phillips, M Wojciak, JM Johnson, RC Clubb, RT AF Sam, MD Papagiannis, CV Connolly, KM Corselli, L Iwahara, J Lee, J Phillips, M Wojciak, JM Johnson, RC Clubb, RT TI Regulation of directionality in bacteriophage lambda site-specific recombination: Structure of the Xis protein SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE NMR; phage excision; protein-DNA interactions; site-specific DNA recombination; structure ID TRIPLE-RESONANCE NMR; INTEGRATION HOST FACTOR; HIGH-LEVEL EXPRESSION; DNA-BINDING; LARGER PROTEINS; EXCISIVE RECOMBINATION; COUPLING-CONSTANTS; ATTACHMENT SITE; GENE-PRODUCT; FIS PROTEIN AB Upon induction of a bacteriophage lambda lysogen, a site-specific recombination reaction excises the phage genome from the chromosome of its bacterial host. A critical regulator of this process is the phage-encoded excisionase (Xis) protein, which functions both as a DNA architectural factor and by cooperatively recruiting integrase to an adjacent binding site specifically required for excision. Here we present the three-dimensional structure of Xis and the results of a structure-based mutagenesis study to define the molecular basis of its function. Xis adopts an unusual 'winged"-helix motif that is modeled to interact with the major- and minor-grooves of its binding site through a single alpha-helix and loop structure ("wing"), respectively. The C-terminal tail of Xis, which is required for cooperative binding with integrase, is unstructured in the absence of DNA. We propose that asymmetric bending of DNA by Xis positions its unstructured C-terminal tail for direct contacts with the N-terminal DNA-binding domain of integrase and that an ensuing disordered to ordered transition of the tail may act to stabilize the formation of the tripartite integrase-Xis-DNA complex required for phage excision. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, UCLA DOE, Lab Struct Biol & Genet, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Sch Med, Dept Biol Chem, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Mol Biol, Los Angeles, CA 90095 USA. RP Johnson, RC (reprint author), Univ Calif Los Angeles, Dept Chem & Biochem, 405 Hilgard Ave, Los Angeles, CA 90095 USA. OI Iwahara, Junji/0000-0003-4732-2173 FU NIGMS NIH HHS [GM57487, GM38509] NR 71 TC 38 Z9 40 U1 0 U2 3 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD DEC 6 PY 2002 VL 324 IS 4 BP 791 EP 805 DI 10.1016/S0022-2836(02)01150-6 PG 15 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 625PR UT WOS:000179825300018 PM 12460578 ER PT J AU Yeh, TCJ Liu, S Glass, RJ Baker, K Brainard, JR Alumbaugh, D LaBrecque, D AF Yeh, TCJ Liu, S Glass, RJ Baker, K Brainard, JR Alumbaugh, D LaBrecque, D TI A geostatistically based inverse model for electrical resistivity surveys and its applications to vadose zone hydrology SO WATER RESOURCES RESEARCH LA English DT Article DE geostatistical inverse model; electrical resistivity tomography; vadose zone; resistivity-moisture relation; spatial variability; sequential/successive linear estimator ID HETEROGENEOUS SOILS; STOCHASTIC-ANALYSIS; UNSATURATED FLOW; DC-RESISTIVITY; HYDRAULIC-HEAD; POROUS-MEDIA; TOMOGRAPHY; TRANSMISSIVITY; REASSESSMENT; SIMULATIONS AB [1] A sequential, geostatistical inverse approach was developed for electrical resistivity tomography (ERT). Unlike most ERT inverse approaches, this new approach allows inclusion of our prior knowledge of general geological structures of an area and point electrical resistivity measurements to constrain the estimate of the electrical resistivity field. This approach also permits sequential inclusion of different data sets, mimicking the ERT data collection scheme commonly employed in the field survey. Furthermore, using the conditional variance concept, the inverse model quantifies uncertainty of the estimate caused by spatial variability and measurement errors. Using this approach, numerical experiments were conducted to demonstrate the effects of bedding orientation on ERT surveys and to show both the usefulness and uncertainty associated with the inverse approach for delineating the electrical resistivity distribution using down- hole ERT arrays. A statistical analysis was subsequently undertaken to explore the effects of spatial variability of the electrical resistivity- moisture relation on the interpretation of the change in water content in the vadose zone, using the change in electrical resistivity. Core samples were collected from a field site to investigate the spatial variability of the electrical resistivity- moisture relation. Numerical experiments were subsequently conducted to illustrate how the spatially varying relations affect the level of uncertainty in the interpretation of change of moisture content based on the estimated change in electrical resistivity. Other possible complications are also discussed. C1 Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. Sandia Natl Labs, Los Alamos, NM USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Univ Wisconsin, Dept Civil & Environm Engn, Madison, WI 53706 USA. MultiPhase Technol, Sparks, NV 89436 USA. RP Yeh, TCJ (reprint author), Univ Arizona, Dept Hydrol & Water Resources, POB 210011, Tucson, AZ 85721 USA. NR 39 TC 70 Z9 71 U1 3 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC 6 PY 2002 VL 38 IS 12 AR 1278 DI 10.1029/2001WR001204 PG 13 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 646EA UT WOS:000181020800005 ER PT J AU Hassett, DJ Cuppoletti, J Trapnell, B Lymar, SV Rowe, JJ Yoon, SS Hilliard, GM Parvatiyar, K Kamani, MC Wozniak, DJ Hwang, SH McDermott, TR Ochsner, UA AF Hassett, DJ Cuppoletti, J Trapnell, B Lymar, SV Rowe, JJ Yoon, SS Hilliard, GM Parvatiyar, K Kamani, MC Wozniak, DJ Hwang, SH McDermott, TR Ochsner, UA TI Anaerobic metabolism and quorum sensing by Pseudomonas aeruginosa biofilms in chronically infected cystic fibrosis airways: rethinking antibiotic treatment strategies and drug targets SO ADVANCED DRUG DELIVERY REVIEWS LA English DT Review DE Pseudomonas aeruginosa; anaerobic growth; cystic fibrosis AB Recent evidence indicates that Pseudomonas aeruginosa residing as biofilms in airway mucus of cystic fibrosis (CF) patients is undergoing anaerobic metabolism, a form of growth requiring gene products that are not utilized during aerobic growth. The outer membrane protein, OprF, and the rhl quorum sensing circuit are two previously unrecognized cellular factors that are required for optimal anaerobic biofilm viability. Without OprF, bacteria grow extremely poorly because they lack nitrite reductase activity while lacking rhlR or rhlI forces bacteria to undergo metabolic suicide by overproduction of nitric oxide. Furthermore, anaerobic growth favors maintenance of the mucoid, alginate-overproducing phenotype. Thus, with increasing age of CF patients, mucoid populations predominate, indicating that anaerobic bacteria reside in the inspissated airway mucus. Because many frontline antibiotics used in the treatment of CF airway disease are either ineffective or show reduced efficacy during anaerobic conditions, we propose development of new drugs to combat anaerobic metabolism by P. aeruginosa for more effective treatment of chronic CF lung infections. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Cincinnati, Coll Med, Dept Mol Genet Biochem & Microbiol, Cincinnati, OH 45267 USA. Univ Cincinnati, Coll Med, Dept Cellular & Mol Physiol, Cincinnati, OH 45267 USA. Childrens Hosp, Med Ctr, Div Pulm Biol, Cincinnati, OH 45229 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Dayton, Dept Biol, Dayton, OH 45469 USA. Wake Forest Univ, Dept Microbiol & Immunol, Winston Salem, NC 27157 USA. Montana State Univ, Ctr Biofilm Engn, Bozeman, MT 59717 USA. Montana State Univ, Dept Land Resources, Bozeman, MT 59717 USA. Univ Colorado Hlth Sci, Dept Microbiol, Denver, CO 80262 USA. RP Hassett, DJ (reprint author), Univ Cincinnati, Coll Med, Dept Mol Genet Biochem & Microbiol, 231 Albert Sabin Way, Cincinnati, OH 45267 USA. FU NIAID NIH HHS [AI-40541] NR 71 TC 168 Z9 176 U1 10 U2 38 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 DEC 5 PY 2002 VL 54 IS 11 BP 1425 EP 1443 AR PII S0169-409X(02)00152-7 DI 10.1016/S0169-409X(02)00152-7 PG 19 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 629WF UT WOS:000180074200006 PM 12458153 ER PT J AU Fawcett, PJ Stalker, JR Gutzler, DS AF Fawcett, PJ Stalker, JR Gutzler, DS TI Multistage moisture transport into the interior of northern Mexico during the North American summer monsoon SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SOUTHWESTERN UNITED-STATES; GULF-OF-CALIFORNIA; LOW-LEVEL JET; SURGES; SYSTEM AB [1] The summertime sources and transport pathways of water vapor into the interior of southwestern North America are examined in a high-resolution mesoscale model simulation. A complex multi-stage transport pathway is associated with a pronounced diurnal cycle of deep convection and low-level wind systems. Daytime thermal pumping of moisture from the Gulf of California towards the Sierra Madre Occidental (SMO) leads to widespread, deep convection. At night, land surface and atmospheric cooling generate drainage flows down both sides of the SMO. A nocturnal, low-level jet forms above the western foothills and transports moisture north into the Sonoran Desert. Moist air draining to the east mixes with onshore flow from Gulf of Mexico and flows into the northern Chihuahuan Desert. The diurnal flow of moisture up and down the SMO and the formation of nocturnal, low-level jets transport moisture into the core regions of the NA monsoon in NW Mexico. C1 Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. Los Alamos Natl Lab, Div Earth & Environm Sci, Atmospher & Climate Sci Grp, Los Alamos, NM 87545 USA. RP Fawcett, PJ (reprint author), Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. NR 15 TC 15 Z9 15 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 5 PY 2002 VL 29 IS 23 AR 2094 DI 10.1029/2002GL015693 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 646YN UT WOS:000181064600005 ER PT J AU Garten, CT Ashwood, TL AF Garten, CT Ashwood, TL TI Landscape level differences in soil carbon and nitrogen: Implications for soil carbon sequestration SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article DE land cover; topography; nitrogen mineralization; nitrification; particulate organic matter; mineral-associated organic matter ID ELEVATED ATMOSPHERIC CO2; ORGANIC-MATTER DYNAMICS; LAND-USE HISTORY; LOBLOLLY-PINE; LITTER DECOMPOSITION; POPULUS-TREMULOIDES; FOREST SUCCESSION; N AVAILABILITY; LIGHT-FRACTION; COASTAL-PLAIN AB [1] The objective of this research was to understand how land cover and topography act, independently or together, as determinants of soil carbon and nitrogen storage over a complex terrain. Such information could help to direct land management for the purpose of carbon sequestration. Soils were sampled under different land covers and at different topographic positions on the mostly forested 14,000 ha Oak Ridge Reservation in Tennessee, USA. Most of the soil carbon stock, to a 40-cm soil depth, was found to reside in the surface 20 cm of mineral soil. Surface soil carbon and nitrogen stocks were partitioned into particulate ( greater than or equal to 53 mum) and mineral-associated organic matter (< 53 μm). Generally, soils under pasture had greater nitrogen availability, greater carbon and nitrogen stocks, and lower C: N ratios than soils under transitional vegetation and forests. The effects of topography were usually secondary to those of land cover. Because of greater soil carbon stocks, and greater allocation of soil carbon to mineral-associated organic matter (a long-term pool), we conclude that soil carbon sequestration, but not necessarily total ecosystem carbon storage, is greater under pastures than under forests. The implications of landscape-level variation in soil carbon and nitrogen for carbon sequestration are discussed at several different levels: (1) nitrogen limitations to soil carbon storage; (2) controls on soil carbon turnover as a result of litter chemistry and soil carbon partitioning; (3) residual effects of past land use history; and (4) statistical limitations to the quantification of soil carbon stocks. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Garten, CT (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 83 TC 19 Z9 19 U1 3 U2 26 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD DEC 5 PY 2002 VL 16 IS 4 AR 1114 DI 10.1029/2002GB001918 PG 14 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 646XX UT WOS:000181062500004 ER PT J AU Randerson, JT Enting, IG Schuur, EAG Caldeira, K Fung, IY AF Randerson, JT Enting, IG Schuur, EAG Caldeira, K Fung, IY TI Seasonal and latitudinal variability of troposphere Delta(CO2)-C-14: Post bomb contributions from fossil fuels, oceans, the stratosphere, and the terrestrial biosphere SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article DE radiocarbon; Suess Effect; carbon cycle; Arctic and boreal ecosystems; Amazon tree rings; meridional gradient of C-14 ID GENERAL-CIRCULATION MODEL; ATMOSPHERIC CARBON-DIOXIDE; EXCESS C-14 DATA; GLOBAL CARBON; SOIL CARBON; RADIOCARBON MEASUREMENTS; DIFFUSION-MODEL; BOREAL FOREST; LAND-USE; CO2 AB [1] During the mid-1960s, large seasonal amplitudes were observed in surface measurements of Delta(14)C in the Northern Hemisphere. These seasonal oscillations were initially caused by stratosphere- troposphere exchange, with the injection of bomb C-14 into the troposphere during winter and spring mixing. Here we show how fossil, ocean, and terrestrial biosphere fluxes modified the stratospheric signal during the 1960s, and the evolution of each of these components in the post bomb era. In our analysis, we used the Goddard Institute for Space Studies (GISS) atmospheric tracer model, gross ocean CO2 fluxes from the Lawrence Livermore National Laboratory (LLNL) ocean model, and terrestrial CO2 fluxes from a biosphere-atmosphere model driven by normalized difference vegetation index and surface air temperatures. We found that C-14-depeleted respiration from the terrestrial biosphere partially canceled the C-14-enriched stratosphere flux in the Northern Hemisphere in the mid and late 1960s. In more recent decades, our analysis suggested that the terrestrial biosphere contribution to the Delta(14)C seasonal cycle reversed phase, with the terrestrial biosphere currently releasing relatively C-14-enriched CO2 that mixes with relatively depleted troposphere CO2. The timing of this reversal depended on the residence times of carbon within the footprint of the observation station. Measurements of Delta(14)C in respiration from tundra and boreal ecosystems in Alaska provide evidence that some boreal forests have undergone this transition, while some tundra ecosystems have not. We predict that over the next century, several features of the latitudinal profile of Delta(14)C will substantially change because of continued fossil fuel emissions in the Northern Hemisphere, and the partial release of bomb C-14 that has accumulated in Southern Hemisphere oceans. C1 CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. CALTECH, Div Engn & Appl Sci, Pasadena, CA 91125 USA. CSIRO Atmospher Res, Aspendale, Vic 3195, Australia. Univ Florida, Dept Bot, Gainesville, FL 32611 USA. Lawrence Livermore Natl Lab, Climate Syst Modeling Grp, Livermore, CA 94550 USA. Univ Calif Berkeley, Ctr Atmospher Sci, Berkeley, CA 94720 USA. RP Randerson, JT (reprint author), CALTECH, Div Geol & Planetary Sci, Mail Stop 100-23, Pasadena, CA 91125 USA. RI Caldeira, Ken/E-7914-2011 NR 84 TC 68 Z9 71 U1 1 U2 28 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD DEC 5 PY 2002 VL 16 IS 4 AR 1112 DI 10.1029/2002GB001876 PG 19 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 646XX UT WOS:000181062500003 ER PT J AU Khalil, HSA Abdelhakim, AA AF Khalil, HSA Abdelhakim, AA TI Adsorption studies of fatty acids on Montmorillonite-based filler clay SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE adsorption; clay; filler; colloid; coating ID NANOCOMPOSITES; CATIONS AB Surface coating of montmorillonite-based filler clay with stearic and oleic (9-octadecenoic acid) acids was presented. Sedimentation measurements showed that the sedimentation rate and the sediment volume decreased sharply with the adsorbed amount of the acid up to a certain concentration and then became constant. The chemical analysis showed that the adsorbed amount of either acid by montmorillonite clay increased with the equilibrium concentration of the acid in the solution. The adsorption isotherm indicated the formation of a monolayer on the clay surface at a lower concentration of the acids followed by formation of multilayers of the acids on the clay surfaces at higher concentrations. XRD analysis indicated no intercalation of either acid in the lamella of the clay. We concluded the possibility of surface coating of montmorillonite clay with a monolayer of fatty acids that render the clay organophilic. The adsorption of either acid improved the dispersibility of the clay particles in organic or polymeric media. (C) 2002 Wiley Periodicals, Inc. C1 Natl Res Ctr, Dept Polymers & Pigments, Cairo, Egypt. Natl Res Ctr, Dept Polymer Sci & Pigments, Cairo, Egypt. RP Khalil, HSA (reprint author), Brookhaven Natl Lab, Energy Resources Div, Upton, NY 11975 USA. NR 19 TC 4 Z9 5 U1 0 U2 4 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD DEC 5 PY 2002 VL 86 IS 10 BP 2574 EP 2580 DI 10.1002/app.11184 PG 7 WC Polymer Science SC Polymer Science GA 599EW UT WOS:000178322000024 ER PT J AU Wang, J Flagan, RC Seinfeld, JH Jonsson, HH Collins, DR Russell, PB Schmid, B Redemann, J Livingston, JM Gao, S Hegg, DA Welton, EJ Bates, D AF Wang, J Flagan, RC Seinfeld, JH Jonsson, HH Collins, DR Russell, PB Schmid, B Redemann, J Livingston, JM Gao, S Hegg, DA Welton, EJ Bates, D TI Clear-column radiative closure during ACE-Asia: Comparison of multiwavelength extinction derived from particle size and composition with results from Sun photometry SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE aerosol optical depth; ACE-Asia; Sun photometer ID EFFECTIVE-MEDIUM APPROXIMATIONS; MID-ATLANTIC COAST; IN-SITU; CHEMICAL-COMPOSITION; OPTICAL-PROPERTIES; UNITED-STATES; WATER-VAPOR; AEROSOL; SCATTERING; BEHAVIOR AB [1] From March to May 2001, aerosol size distributions and chemical compositions were measured using differential mobility analyzers (DMA), an aerodynamic particle sizer (APS), Micro-Orifice Uniform Deposit Impactors (MOUDI), and denuder samplers onboard the Twin Otter aircraft as part of the Aerosol Characterization Experiment (ACE)-Asia campaign. Of the 19 research flights, measurements on four flights that represented different aerosol characteristics are analyzed in detail. Clear-column radiative closure is studied by comparing aerosol extinctions predicted using in situ aerosol size distribution and chemical composition measurements to those derived from the 14-wavelength NASA Ames Airborne Tracking Sun photometer (AATS-14). In the boundary layer, pollution layers, and free troposphere with no significant mineral dust present, aerosol extinction closure was achieved within the estimated uncertainties over the full range of wavelengths of AATS-14. Aerosol extinctions predicted based on measured size distributions also reproduce the wavelength dependence derived from AATS-14 data. Considering all four flights, the best fit lines yield Predicted/Observed ratios in boundary and pollution layers of 0.97 +/- 0.24 and 1.07 +/- 0.08 at lambda = 525 nm and 0.96 +/- 0.21 and 1.08 +/- 0.08 at lambda = 1059 nm, respectively. In free troposphere dust layers, aerosol extinctions predicted from the measured size distributions were generally smaller than those derived from the AATS-14 data, with Predicted/Observed ratios of 0.65 +/- 0.06 and 0.66 +/- 0.05 at 525 and 1059 nm, respectively. A detailed analysis suggests that the discrepancy is likely a result of the lack of the knowledge of mineral dust shape as well as variations in aerosol extinction derived from AATS-14 data when viewing through horizontally inhomogeneous layers. C1 CALTECH, Dept Chem Engn, Pasadena, CA 91125 USA. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93933 USA. Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Bay Area Environm Res Inst, Sonoma, CA 94035 USA. SRI Int, Menlo Pk, CA 94035 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. NASA, Goddard Earth Sci & Technol Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Greenbelt, MD 20771 USA. Univ Miami, Dept Phys, Coral Gables, FL 33124 USA. RP Wang, J (reprint author), Brookhaven Natl Lab, Dept Environm Sci, 75 Rutherford Dr, Upton, NY 11973 USA. EM seinfeld@caltech.edu RI Welton, Ellsworth/A-8362-2012; Collins, Don/F-9617-2012; Wang, Jian/G-9344-2011 NR 43 TC 52 Z9 52 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 5 PY 2002 VL 107 IS D23 AR 4688 DI 10.1029/2002JD002465 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 646VL UT WOS:000181056200005 ER PT J AU Wheelock, CE Colvin, ME Uemura, I Olmstead, MM Sanborn, JR Nakagawa, Y Jones, AD Hammock, BD AF Wheelock, CE Colvin, ME Uemura, I Olmstead, MM Sanborn, JR Nakagawa, Y Jones, AD Hammock, BD TI Use of ab initio calculations to predict the biological potency of carboxylesterase inhibitors SO JOURNAL OF MEDICINAL CHEMISTRY LA English DT Article ID JUVENILE-HORMONE ESTERASE; TRIFLUOROMETHYL KETONE INHIBITORS; HUMAN LIVER CARBOXYLESTERASE; HUMAN-LEUKOCYTE ELASTASE; MAMMALIAN CARBOXYLESTERASES; AFFINITY PURIFICATION; ENZYMATIC-HYDROLYSIS; CHEMICAL PROCESSES; DRUG DESIGN; MODEL AB Carboxylesterases are important enzymes responsible for the hydrolysis and metabolism of numerous pharmaceuticals and xenobiotics. These enzymes are potently inhibited by trifluoromethyl ketone containing (TFK) inhibitors. We demonstrated that the ketone hydration state was affected by the surrounding chemical moieties and was related to inhibitor potency, with inhibitors that favored the gem-diol conformation exhibiting greater potency. Ab initio calculations were performed to determine the energy of hydration of the ketone, and the values were correlated with esterase inhibition data for a series of carboxylesterase inhibitors. This system was examined in three different mammalian models (human liver microsomes, murine liver microsomes, and commercial porcine liver esterase) and in an insect enzyme preparation juvenile hormone esterase). In all cases, the extent of ketone hydration was strongly correlated with biological potency. Our results showed a very strong correlation with the extent of hydration, accounting for 94% of activity for human liver microsome esterase inhibition (p < 0.01). The atomic charge on the carbon atom of the carbonyl group in the TFK also strongly correlated with inhibitor potency, accounting for 94% of inhibition activity in human liver microsomes (p < 0.01). In addition, we provide crystallographic evidence of intramolecular hydrogen bonding in sulfur-containing inhibitors and relate these data to gem-diol formation. This study provides insight into the mechanism of carboxylesterase inhibition and raises the possibility that inhibitors that too strongly favor the gem-diol configuration have decreased potency due to low rate of ketone formation. C1 Univ Calif Davis, Dept Entomol, Davis, CA 95616 USA. Univ Calif Davis, Canc Res Ctr, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Kyoto Univ, Grad Sch Agr, Div Appl Life Sci, Kyoto 6068502, Japan. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. Penn State Univ, Dept Chem, University Pk, PA 16802 USA. RP Hammock, BD (reprint author), Univ Calif Davis, Dept Entomol, Davis, CA 95616 USA. EM bdhammock@ucdavis.edu RI Jones, Arthur/C-2670-2013 OI Jones, Arthur/0000-0002-7408-6690 FU NIEHS NIH HHS [R37 ES02710, P30 ES 05707, P42 ES04699] NR 83 TC 28 Z9 28 U1 2 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-2623 J9 J MED CHEM JI J. Med. Chem. PD DEC 5 PY 2002 VL 45 IS 25 BP 5576 EP 5593 DI 10.1021/jm020072w PG 18 WC Chemistry, Medicinal SC Pharmacology & Pharmacy GA 622EA UT WOS:000179632500019 PM 12459025 ER PT J AU Stefan, IC Mo, YB Antonio, MR Scherson, DA AF Stefan, IC Mo, YB Antonio, MR Scherson, DA TI In situ Ru L-II, and Li-III edge X-ray absorption near edge structure of electrodeposited ruthenium dioxide films SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Letter ID IRIDIUM OXIDE-FILMS; WHITE LINES; DEPOSITION; VALENCY; METALS AB The electronic properties of electrodeposited Ru oxide films supported on Au have been examined in situ by Ru. L-III and L-II edge X-ray absorption near edge structure (XANES) in acid media. The results obtained are consistent with the main voltammetric peak centered at 0.7 V vs RHE as being attributed to a redox couple involving formally Ru3+ and Ru4+ sites in the lattice. A linear correlation was found between the extent of oxidation of the film as derived from a deconvolution of the spectral features and the charge as determined from coulomteric analysis of the voltammetric curves. This observation suggests that only two Ru-based redox states are involved in this electrochemical process. C1 Case Western Reserve Univ, Dept Chem, Cleveland, OH 44106 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Scherson, DA (reprint author), Case Western Reserve Univ, Dept Chem, Cleveland, OH 44106 USA. NR 16 TC 13 Z9 13 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 DEC 5 PY 2002 VL 106 IS 48 BP 12373 EP 12375 DI 10.1021/jp026300f PG 3 WC Chemistry, Physical SC Chemistry GA 621YH UT WOS:000179618200004 ER PT J AU Hwang, SJ Petkov, V Rangan, KK Shastri, S Kanatzidis, MG AF Hwang, SJ Petkov, V Rangan, KK Shastri, S Kanatzidis, MG TI Structure of nanocrystalline materials with intrinsic disorder from atomic pair distribution function analysis: The intercalation compound AgxMoS2 SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MOLYBDENUM-DISULFIDE; METAL SULFIDES; NEUTRON-DIFFRACTION; RESTACKED MOS2; ENCAPSULATION; WS2; NANOCOMPOSITES; TRANSITION; LAYERS; POLYMERS AB The full three-dimensional structure of Ag-intercalated molybdenum disulfide has been experimentally determined. The atomic pair distribution function (PDF) analysis technique has been employed because of the very limited structural coherence in this nanocrystalline material. We found that at the atomic scale, this compound can be well-described as an assembly of anionic MoS2 slabs encapsulating the Ag+ ions. Silver is found in an almost linear coordination of two sulfur atoms at 2.41 and 2.46 Angstrom. The molybdenum atoms engage in strong metal-metal bonding giving rise to Mo-Mo zigzag chains within the MoS2 slabs. This study demonstrates the effectiveness of PDF technique in determining the structure of poorly diffracting, heavily disordered, and nanocrystalline materials. The new structural information obtained for AgxMoS2 could not have been obtained by any other currently available technique. C1 Michigan State Univ, Dept Chem, E Lansing, MI 48824 USA. Michigan State Univ, Ctr Fundamental Mat Res, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Kanatzidis, MG (reprint author), Michigan State Univ, Dept Chem, E Lansing, MI 48824 USA. NR 42 TC 15 Z9 15 U1 2 U2 17 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 DEC 5 PY 2002 VL 106 IS 48 BP 12453 EP 12458 DI 10.1021/jp0263469 PG 6 WC Chemistry, Physical SC Chemistry GA 621YH UT WOS:000179618200013 ER PT J AU Camillone, N Adib, K Khan, KA Mocuta, D Osgood, RM AF Camillone, N Adib, K Khan, KA Mocuta, D Osgood, RM TI Dimethyl sulfide formation from adsorbed methanethiol: Surface trapping of UV-generated reaction intermediates SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ELECTRON TRANSMISSION SPECTROSCOPY; SELF-ASSEMBLED MONOLAYERS; DISSOCIATIVE ATTACHMENT; ORGANOSULFUR COMPOUNDS; 193 NM; CH3SH; GALLIUM-ARSENIDE(110); DECOMPOSITION; DEPENDENCE; RESONANCES AB We present studies of the photoinduced surface chemistry of methanethiol adsorbed on GaAs(110). UV irradiation of these molecules, which are intact at similar to90 K, induces scission of the S-H. bond, leaving the CH3S fragment trapped at the surface. The measured cross section at 193 nm for this photoinduced process is similar to3.6 x 10(-10) cm(2). Postirradiation heating of the surface-bound products of the methanethiol photoreaction results in the evolution of dimethyl sulfide with the same desorption kinetics as observed for the strictly thermal production of dimethyl sulfide from dissociatively adsorbed methyl disulfide. Thus, UV irradiation of CH3SH/GaAs(110) followed by thermal activation of the surface-trapped intermediates is shown to provide a new route to partial desulfurization of CH3SH. C1 Columbia Univ, Columbia Radiat Lab, New York, NY 10027 USA. Columbia Univ, Dept Appl Phys & Appl Math, Mat Sci Program, New York, NY 10027 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Camillone, N (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 29 TC 7 Z9 7 U1 0 U2 5 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 DEC 5 PY 2002 VL 106 IS 48 BP 12491 EP 12498 DI 10.1021/jp021333g PG 8 WC Chemistry, Physical SC Chemistry GA 621YH UT WOS:000179618200019 ER PT J AU Worden, K Sohn, H Farrar, CR AF Worden, K Sohn, H Farrar, CR TI Novelty detection in a changing environment: Regression and interpolation approaches SO JOURNAL OF SOUND AND VIBRATION LA English DT Article AB The technique of novelty detection is now established as a means of performing the lowest level of damage identification. Data are accumulated while the system or structure is operating in normal condition and used to construct a reference model. During subsequent operation of the system, data are compared to the reference and any significant deviations are taken to indicate damage. This approach has potential problems if the system or structure is embedded in a changing environment. If the reference data are only characteristic of a limited range of the environmental parameters, measurements from the system in an undamaged condition but from a different environmental state, may cause the diagnostic to register novelty and thus falsely infer damage. This paper demonstrates a potential solution to the problem via the construction of a reference set parametrized by an environmental variable. Two approaches are considered: regression and interpolation. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 Los Alamos Natl Lab, Grp ESA EA, Los Alamos, NM 87544 USA. RP Worden, K (reprint author), Los Alamos Natl Lab, Grp ESA EA, POB 1663, Los Alamos, NM 87544 USA. RI Farrar, Charles/C-6954-2012 NR 14 TC 63 Z9 65 U1 0 U2 2 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD DEC 5 PY 2002 VL 258 IS 4 BP 741 EP 761 DI 10.1006/jsvi.2002.5148 PG 21 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 626KY UT WOS:000179872500009 ER PT J AU Lee, Y Vogt, T Hriljac, JA Parise, JB Hanson, JC Kim, SJ AF Lee, Y Vogt, T Hriljac, JA Parise, JB Hanson, JC Kim, SJ TI Non-framework cation migration and irreversible pressure-induced hydration in a zeolite SO NATURE LA English DT Article ID X-RAY; MOLECULAR-SIEVE; DIFFRACTION; NATROLITE; TEMPERATURE; PORES; RHO AB Zeolites crystallize in a variety of three-dimensional structures in which oxygen atoms are shared between tetrahedra containing silicon and/or aluminium, thus yielding negatively charged tetrahedral frameworks that enclose cavities and pores of molecular dimensions occupied by charge-balancing metal cations and water molecules(1). Cation migration in the pores and changes in water content associated with concomitant relaxation of the framework have been observed in numerous variable-temperature studies(2-5), whereas the effects of hydrostatic pressure on the structure and properties of zeolites are less well explored(6-8). The zeolite sodium aluminosilicate natrolite was recently shown to undergo a volume expansion at pressures above 1.2 GPa as a result of reversible pressure-induced hydration(9); in contrast, a synthetic analogue, potassium gallosilicate natrolite, exhibited irreversible pressure-induced hydration with retention of the high-pressure phase at ambient conditions(10). Here we report the structure of the high-pressure recovered phase and contrast it with the high-pressure phase of the sodium aluminosilicate natrolite. Our findings show that the irreversible hydration behaviour is associated with a pronounced rearrangement of the non-framework metal ions, thus emphasizing that they can clearly have an important role in mediating the overall properties of zeolites. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Birmingham, Sch Chem Sci, Birmingham B15 2TT, W Midlands, England. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Korea Inst Sci & Technol, Nanomat Res Ctr, Seoul 130650, South Korea. RP Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM tvogt@bnl.gov RI Hanson, jonathan/E-3517-2010; Vogt, Thomas /A-1562-2011; Lee, Yongjae/K-6566-2016 OI Vogt, Thomas /0000-0002-4731-2787; NR 15 TC 102 Z9 102 U1 5 U2 38 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 EI 1476-4687 J9 NATURE JI Nature PD DEC 5 PY 2002 VL 420 IS 6915 BP 485 EP 489 DI 10.1038/nature01265 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 621VK UT WOS:000179611600040 PM 12466838 ER PT J AU Waterston, RH Lindblad-Toh, K Birney, E Rogers, J Abril, JF Agarwal, P Agarwala, R Ainscough, R Alexandersson, M An, P Antonarakis, SE Attwood, J Baertsch, R Bailey, J Barlow, K Beck, S Berry, E Birren, B Bloom, T Bork, P Botcherby, M Bray, N Brent, MR Brown, DG Brown, SD Bult, C Burton, J Butler, J Campbell, RD Carninci, P Cawley, S Chiaromonte, F Chinwalla, AT Church, DM Clamp, M Clee, C Collins, FS Cook, LL Copley, RR Coulson, A Couronne, O Cuff, J Curwen, V Cutts, T Daly, M David, R Davies, J Delehaunty, KD Deri, J Dermitzakis, ET Dewey, C Dickens, NJ Diekhans, M Dodge, S Dubchak, I Dunn, DM Eddy, SR Elnitski, L Emes, RD Eswara, P Eyras, E Felsenfeld, A Fewell, GA Flicek, P Foley, K Frankel, WN Fulton, LA Fulton, RS Furey, TS Gage, D Gibbs, RA Glusman, G Gnerre, S Goldman, N Goodstadt, L Grafham, D Graves, TA Green, ED Gregory, S Guigo, R Guyer, M Hardison, RC Haussler, D Hayashizaki, Y Hillier, LW Hinrichs, A Hlavina, W Holzer, T Hsu, F Hua, A Hubbard, T Hunt, A Jackson, I Jaffe, DB Johnson, LS Jones, M Jones, TA Joy, A Kamal, M Karlsson, EK Karolchik, D Kasprzyk, A Kawai, J Keibler, E Kells, C Kent, WJ Kirby, A Kolbe, DL Korf, I Kucherlapati, RS Kulbokas, EJ Kulp, D Landers, T Leger, JP Leonard, S Letunic, I Levine, R Li, J Li, M Lloyd, C Lucas, S Ma, B Maglott, DR Mardis, ER Matthews, L Mauceli, E Mayer, JH McCarthy, M McCombie, WR McLaren, S McLay, K McPherson, JD Meldrim, J Meredith, B Mesirov, JP Miller, W Miner, TL Mongin, E Montgomery, KT Morgan, M Mott, R Mullikin, JC Muzny, DM Nash, WE Nelson, JO Nhan, MN Nicol, R Ning, Z Nusbaum, C O'Connor, MJ Okazaki, Y Oliver, K Larty, EO Pachter, L Parra, G Pepin, KH Peterson, J Pevzner, P Plumb, R Pohl, CS Poliakov, A Ponce, TC Ponting, CP Potter, S Quail, M Reymond, A Roe, BA Roskin, KM Rubin, EM Rust, AG Santos, R Sapojnikov, V Schultz, B Schultz, J Schwartz, MS Schwartz, S Scott, C Seaman, S Searle, S Sharpe, T Sheridan, A Shownkeen, R Sims, S Singer, JB Slater, G Smit, A Smith, DR Spencer, B Stabenau, A Strange-Thomann, NS Sugnet, C Suyama, M Tesler, G Thompson, J Torrents, D Trevaskis, E Tromp, J Ucla, C Vidal, AU Vinson, JP von Niederhausern, AC Wade, CM Wall, M Weber, RJ Weiss, RB Wendl, MC West, AP Wetterstrand, K Wheeler, R Whelan, S Wierzbowski, J Willey, D Williams, S Wilson, RK Winter, E Worley, KC Wyman, D Yang, S Yang, SP Zdobnov, EM Zody, MC Lander, ES AF Waterston, RH Lindblad-Toh, K Birney, E Rogers, J Abril, JF Agarwal, P Agarwala, R Ainscough, R Alexandersson, M An, P Antonarakis, SE Attwood, J Baertsch, R Bailey, J Barlow, K Beck, S Berry, E Birren, B Bloom, T Bork, P Botcherby, M Bray, N Brent, MR Brown, DG Brown, SD Bult, C Burton, J Butler, J Campbell, RD Carninci, P Cawley, S Chiaromonte, F Chinwalla, AT Church, DM Clamp, M Clee, C Collins, FS Cook, LL Copley, RR Coulson, A Couronne, O Cuff, J Curwen, V Cutts, T Daly, M David, R Davies, J Delehaunty, KD Deri, J Dermitzakis, ET Dewey, C Dickens, NJ Diekhans, M Dodge, S Dubchak, I Dunn, DM Eddy, SR Elnitski, L Emes, RD Eswara, P Eyras, E Felsenfeld, A Fewell, GA Flicek, P Foley, K Frankel, WN Fulton, LA Fulton, RS Furey, TS Gage, D Gibbs, RA Glusman, G Gnerre, S Goldman, N Goodstadt, L Grafham, D Graves, TA Green, ED Gregory, S Guigo, R Guyer, M Hardison, RC Haussler, D Hayashizaki, Y Hillier, LW Hinrichs, A Hlavina, W Holzer, T Hsu, F Hua, A Hubbard, T Hunt, A Jackson, I Jaffe, DB Johnson, LS Jones, M Jones, TA Joy, A Kamal, M Karlsson, EK Karolchik, D Kasprzyk, A Kawai, J Keibler, E Kells, C Kent, WJ Kirby, A Kolbe, DL Korf, I Kucherlapati, RS Kulbokas, EJ Kulp, D Landers, T Leger, JP Leonard, S Letunic, I Levine, R Li, J Li, M Lloyd, C Lucas, S Ma, B Maglott, DR Mardis, ER Matthews, L Mauceli, E Mayer, JH McCarthy, M McCombie, WR McLaren, S McLay, K McPherson, JD Meldrim, J Meredith, B Mesirov, JP Miller, W Miner, TL Mongin, E Montgomery, KT Morgan, M Mott, R Mullikin, JC Muzny, DM Nash, WE Nelson, JO Nhan, MN Nicol, R Ning, Z Nusbaum, C O'Connor, MJ Okazaki, Y Oliver, K Larty, EO Pachter, L Parra, G Pepin, KH Peterson, J Pevzner, P Plumb, R Pohl, CS Poliakov, A Ponce, TC Ponting, CP Potter, S Quail, M Reymond, A Roe, BA Roskin, KM Rubin, EM Rust, AG Santos, R Sapojnikov, V Schultz, B Schultz, J Schwartz, MS Schwartz, S Scott, C Seaman, S Searle, S Sharpe, T Sheridan, A Shownkeen, R Sims, S Singer, JB Slater, G Smit, A Smith, DR Spencer, B Stabenau, A Strange-Thomann, NS Sugnet, C Suyama, M Tesler, G Thompson, J Torrents, D Trevaskis, E Tromp, J Ucla, C Vidal, AU Vinson, JP von Niederhausern, AC Wade, CM Wall, M Weber, RJ Weiss, RB Wendl, MC West, AP Wetterstrand, K Wheeler, R Whelan, S Wierzbowski, J Willey, D Williams, S Wilson, RK Winter, E Worley, KC Wyman, D Yang, S Yang, SP Zdobnov, EM Zody, MC Lander, ES CA Mouse Genome Sequencing Consor TI Initial sequencing and comparative analysis of the mouse genome SO NATURE LA English DT Review ID SEMINAL-VESICLE AUTOANTIGEN; SINGLE-NUCLEOTIDE POLYMORPHISMS; CONSERVED NONCODING SEQUENCES; HOMOGENEOUSLY STAINING REGION; PROLACTIN-INDUCIBLE PROTEIN; X-CHROMOSOME INACTIVATION; KILLER-CELL RECEPTORS; RADIATION HYBRID MAP; FACTOR-BINDING SITES; TRANSFER-RNA GENES AB The sequence of the mouse genome is a key informational tool for understanding the contents of the human genome and a key experimental tool for biomedical research. Here, we report the results of an international collaboration to produce a high-quality draft sequence of the mouse genome. We also present an initial comparative analysis of the mouse and human genomes, describing some of the insights that can be gleaned from the two sequences. We discuss topics including the analysis of the evolutionary forces shaping the size, structure and sequence of the genomes; the conservation of large-scale synteny across most of the genomes; the much lower extent of sequence orthology covering less than half of the genomes; the proportions of the genomes under selection; the number of protein-coding genes; the expansion of gene families related to reproduction and immunity; the evolution of proteins; and the identification of intraspecies polymorphism. C1 Washington Univ, Sch Med, Genome Sequencing Ctr, St Louis, MO 63108 USA. MIT, Ctr Genome Res, Whitehead Inst, Cambridge, MA 02141 USA. European Bioinformat Inst, Cambridge CB10 1SD, England. Wellcome Trust Sanger Inst, Cambridge CB10 1SA, England. Univ Pompeu Fabra, Inst Municipal Invest Med, Res Grp Biomed Informat, Barcelona, Catalonia, Spain. GlaxoSmithKline Inc, King Of Prussia, PA 19406 USA. NIH, Natl Ctr Biotechnol Informat, Bethesda, MD 20892 USA. Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. Univ Geneva, Sch Med, Div Med Genet, CH-1211 Geneva 10, Switzerland. Univ Calif Santa Cruz, Ctr Biomol Sci & Engn, Santa Cruz, CA 95064 USA. European Mol Biol Lab, D-69117 Heidelberg, Germany. MRC, Mammalian Genet Unit, UK MRC Mouse Sequencing Consortium, Harwell OX11 0RD, Berks, England. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Washington Univ, Dept Comp Sci, St Louis, MO 63130 USA. Univ Waterloo, Sch Comp Sci, Waterloo, ON N2L 3G1, Canada. Jackson Lab, Bar Harbor, ME 04609 USA. Yokohama Inst, RIKEN Genom Sci Ctr, Lab Genome Explorat, Kanagawa 2300045, Japan. Affymetrix Inc, Oakland, CA 94608 USA. Penn State Univ, Dept Stat, University Pk, PA 16802 USA. Penn State Univ, Dept Hlth Evaluat Sci, University Pk, PA 16802 USA. NHGRI, NIH, Bethesda, MD 20892 USA. Univ Oxford, Wellcome Trust Ctr Human Genet, Oxford OX3 7BN, England. Univ Calif Berkeley, Dept Elect Engn, Berkeley, CA 94720 USA. Univ Oxford, Dept Human Anat & Genet, MRC, Funct Genet Unit, Oxford OX1 3QX, England. Univ Utah, Dept Human Genet, Salt Lake City, UT 84112 USA. Washington Univ, Sch Med, Howard Hughes Med Inst, St Louis, MO 63110 USA. Washington Univ, Sch Med, Dept Genet, St Louis, MO 63110 USA. Penn State Univ, Dept Biochem & Mol Biol, University Pk, PA 16802 USA. Penn State Univ, Dept Comp Sci & Engn, University Pk, PA 16802 USA. Baylor Coll Med, Human Genome Sequencing Ctr, Houston, TX 77030 USA. Inst Syst Biol, Seattle, WA 98103 USA. NHGRI, NIH, Bethesda, MD 20892 USA. Univ Calif Santa Cruz, Howard Hughes Med Inst, Santa Cruz, CA 95064 USA. Univ Oklahoma, Dept Chem & Biochem, Adv Ctr Genome Technol, Norman, OK 73019 USA. Harvard Univ, Sch Med, Dept Genet, Boston, MA 02115 USA. Harvard Univ, Sch Med, Dept Med, Boston, MA 02115 USA. Harvard Univ, Sch Med, Harvard Partners Ctr Genet & Genom, Boston, MA 02115 USA. Penn State Univ, Dept Stat, University Pk, PA 16802 USA. Univ Calif Santa Barbara, Dept Comp Sci, Santa Barbara, CA 93106 USA. US DOE, Joint Genome Inst, Walnut Creek, CA 94598 USA. Univ Western Ontario, Dept Comp Sci, London, ON N6A 5B7, Canada. Cold Spring Harbor Lab, Cold Spring Harbor, NY 11724 USA. Wellcome Trust Res Labs, London NW1 2BE, England. Univ Calif San Diego, Dept Comp Sci & Engn, La Jolla, CA 92093 USA. Max Planck Inst Mol Genet, D-14195 Berlin, Germany. Genome Therapeut Corp, Waltham, MA 02453 USA. Bioinformat Solut Inc, Waterloo, ON N2L 3L2, Canada. Baylor Coll Med, Dept Mol & Human Genet, Houston, TX 77030 USA. MIT, Dept Biol, Cambridge, MA 02138 USA. RP Waterston, RH (reprint author), Washington Univ, Sch Med, Genome Sequencing Ctr, Campus Box 8501,4444 Forest Pk Ave, St Louis, MO 63108 USA. EM waterston@gs.washington.edu; kersli@genome.wi.mit.edu RI Torrents, David/G-5785-2015; Abril Ferrando, Josep/B-3877-2014; Carninci, Piero/K-1568-2014; Eyras, Eduardo/L-1053-2014; Antonarakis, Stylianos/N-8866-2014; Ning, Zemin/D-2411-2013; Guigo, Roderic/D-1303-2010; Kawai, Jun/A-6451-2016; Gasull, Martina/A-6630-2013; Wendl, Michael/A-2741-2008; Ma, Bin/C-7550-2013; Bork, Peer/F-1813-2013; Schultz, Joerg/B-9346-2008; Hubbard, Tim/C-2567-2008; Letunic, Ivica/A-6032-2009; Hardison, Ross/G-1142-2010; Whelan, Simon/A-6638-2011; Eyras, Eduardo/A-1560-2010; Emes, Richard/C-5341-2008; Couronne, Olivier Couronne/G-1244-2012; Zdobnov, Evgeny/K-1133-2012; Seaman, Steven/A-2755-2013; Dermitzakis, Emmanouil/B-7687-2013 OI Hinrichs, Angie/0000-0002-1697-1130; Letunic, Ivica/0000-0003-3560-4288; Ponting, Chris/0000-0003-0202-7816; Glusman, Gustavo/0000-0001-8060-5955; Dickens, Nicholas/0000-0003-0492-5855; Eddy, Sean/0000-0001-6676-4706; Rust, Alistair/0000-0001-7287-192X; Furey, Terry/0000-0001-5546-9672; Torrents, David/0000-0002-6086-9037; McCombie, W. Richard/0000-0003-1899-0682; Schultz, Brian/0000-0003-4964-976X; Goldman, Nick/0000-0001-8486-2211; Flicek, Paul/0000-0002-3897-7955; Wade, Claire/0000-0003-3413-4771; Birney, Ewan/0000-0001-8314-8497; Abril Ferrando, Josep/0000-0001-7793-589X; Carninci, Piero/0000-0001-7202-7243; Eyras, Eduardo/0000-0003-0793-6218; Antonarakis, Stylianos/0000-0001-8907-5823; Guigo, Roderic/0000-0002-5738-4477; Agarwal, Pankaj/0000-0002-4165-9990; Karlsson, Elinor/0000-0002-4343-3776; Hunt, Adrienne/0000-0002-1227-0310; Ning, Zemin/0000-0003-4359-776X; Bork, Peer/0000-0002-2627-833X; Hubbard, Tim/0000-0002-1767-9318; Hardison, Ross/0000-0003-4084-7516; Emes, Richard/0000-0001-6855-5481; Seaman, Steven/0000-0003-3349-3334; NR 330 TC 3898 Z9 4058 U1 41 U2 294 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD DEC 5 PY 2002 VL 420 IS 6915 BP 520 EP 562 DI 10.1038/nature01262 PG 43 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 621VK UT WOS:000179611600053 ER PT J AU Davoudiasl, H Hewett, JL Rizzo, TG AF Davoudiasl, H Hewett, JL Rizzo, TG TI Gravi-burst: super-GZK cosmic rays from localized gravity SO PHYSICS LETTERS B LA English DT Article ID ZATSEPIN-KUZMIN CUTOFF; ENERGY-SPECTRUM; PROPAGATION; HIERARCHY; LIMITS; ARRAY; FLUX; WELL AB The flux of cosmic rays beyond the GZK cutoff (similar to 10(20) eV) may be explained through their production by ultra high energy cosmic neutrinos, annihilating on the relic neutrino background, in the vicinity of our galaxy. This process; known as the Z-burst mechanism, is mediated through the production of a Z boson at resonance. We propose a similar mechanism and call it gravi-burst, where the particles produced at resonance are the Kaluza-Klein gravitons of weak scale mass and coupling from the Randall-Sundrum hierarchy model of localized gravity. Under certain assumptions about the energy spectrum of the primary neutrinos we find that cosmic ray data could be potentially as powerful as the LHC in probing this model. (C) 2002 Published by Elsevier Science B.V. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM hewett@slac.stanford.edu NR 25 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD DEC 5 PY 2002 VL 549 IS 3-4 BP 267 EP 272 AR PII S0370-2693(02)02938-6 DI 10.1016/S0370-2693(02)02938-6 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 624UY UT WOS:000179781200001 ER PT J AU Kim, F Song, JH Yang, PD AF Kim, F Song, JH Yang, PD TI Photochemical synthesis of gold nanorods SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID PARTICLES; NANOPARTICLES; TEMPLATE C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. RP Yang, PD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. OI Kim, Franklin/0000-0002-6548-6588 NR 20 TC 796 Z9 817 U1 17 U2 234 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 DEC 4 PY 2002 VL 124 IS 48 BP 14316 EP 14317 DI 10.1021/ja028110o PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 620AP UT WOS:000179510800018 PM 12452700 ER PT J AU Ahmadi, G Smith, DH AF Ahmadi, G Smith, DH TI Gas flow and particle deposition in the hot-gas filter vessel of the Pinon Pine project SO POWDER TECHNOLOGY LA English DT Article DE gas flow; hot-gas filter vessel; Pinon Pine project ID OPERATIONAL FILTRATION DATA; TURBULENT DEPOSITION; ROUGH SURFACES; PLANT; PFBC; TRANSPORT; BEHAVIOR; SMOOTH; MODEL AB Advanced pressurized fluidized bed combustors (PFBC) and integrated gasification combined cycles (IGCC) as economical clean coal technologies for the 21st century have attracted considerable attention. The success of these advanced coal energy systems hinges on effective and reliable commercial-scale filtration of gases at very high temperatures. The Pinon Pine hot-gas filtration system is the first industrial-scale application of an advanced particle filtration system in the United States. The system currently is becoming operational and will provide significant practical insights into operation of the industrial-scale hot-gas cleaning process. This study is concerned with a computer simulation of hot-gas flow and particle transport and deposition in the Pinon Pine filter vessel. The FLUENT(TM) code is used for evaluating the gas mean velocity, mean pressure, and the state of turbulence in the filter vessel. The 748 filters arranged into four tiers are modeled as four effective cylindrical filters. The particle equation of motion that includes the nonlinear drag and the gravity is used. The particle deposition patterns are evaluated, and the effect of particle size is studied. The results show that, for clean filters, the particle deposition rate of particles on different tiers depends on particle size. These differences could lead to nonuniform cake compositions and thichnesses on the candle filters in different tiers. (C) 2002 Published by Elsevier Science B.V. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. Clarkson Univ, Dept Mech & Aeronaut Engn, Potsdam, NY 13699 USA. RP Smith, DH (reprint author), US DOE, Natl Energy Technol Lab, POB 880, Morgantown, WV 26507 USA. NR 37 TC 17 Z9 18 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD DEC 4 PY 2002 VL 128 IS 1 BP 1 EP 10 AR PII S0032-5910(02)00166-3 DI 10.1016/S0032-5910(02)00166-3 PG 10 WC Engineering, Chemical SC Engineering GA 619LK UT WOS:000179477300001 ER PT J AU Yamakov, V Wolf, D Phillpot, SR Gleiter, H AF Yamakov, V Wolf, D Phillpot, SR Gleiter, H TI Deformation twinning in nanocrystalline Al by molecular dynamics simulation SO ACTA MATERIALIA LA English DT Article DE computer simulation; nanocrystal; aluminium; deformation twinning; dislocations ID STACKING-FAULT ENERGY; ATOMISTIC SIMULATIONS; GRAIN-SIZE; CRYSTAL; METALS; NANOINDENTATION; DISLOCATIONS; POTENTIALS; NUCLEATION AB We use a recently developed, massively parallel molecular-dynamics code for the simulation of polycrystal plasticity to elucidate the intricate interplay between dislocation and GB processes during room-temperature plastic deformation of model nanocrystalline-Al microstructures. Our simulations reveal that under relatively high stresses (of 2.5 GPa) and large plastic strains (of similar to12%), extensive deformation twinning takes place, in addition to deformation by the conventional dislocation-slip mechanism. Both heterogeneous and homogeneous nucleation of deformation twins is observed. The heterogeneous mechanism involves the successive emission of Shockley partials from the grain boundaries onto neighboring slip planes. By contrast, the homogeneous process takes place in the grain interiors, by a nucleation mechanism involving the dynamical overlap of the stacking faults of intrinsically and/or extrinsically dissociated dislocations. Our simulations also reveal the mechanism for the formation of a new grain, via an intricate interplay between deformation twinning and dislocation nucleation from the grain boundaries during the deformation. The propensity for deformation twinning observed in our simulations is surprising, given that the process has never been observed in coarse-grained Al and that the well-known pole mechanism cannot operated for such a small grain size. It therefore appears that the basic models for deformation twinning should be extended with particular emphasis on the role of grain-boundary sources in nanocrystalline materials. (C) 2002 Published by Elsevier Science Ltd on behalf of Acta Materialia Inc. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Forschungszentrum Karlsruhe, D-76021 Karlsruhe, Germany. RP Yamakov, V (reprint author), Argonne Natl Lab, Div Sci Mat, Bldg 212,9700 S Cass Ave, Argonne, IL 60439 USA. RI Phillpot, Simon/J-9117-2012; OI Phillpot, Simon/0000-0002-7774-6535 NR 44 TC 283 Z9 299 U1 13 U2 148 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 DEC 3 PY 2002 VL 50 IS 20 BP 5005 EP 5020 AR PII S1359-6454(02)00318-X DI 10.1016/S1359-6454(02)00318-X PG 16 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 619LW UT WOS:000179478300006 ER PT J AU Tomson, F Bailey, JA Gennis, RB Unkefer, CJ Li, ZH Silks, LA Martinez, RA Donohoe, RJ Dyer, RB Woodruff, WH AF Tomson, F Bailey, JA Gennis, RB Unkefer, CJ Li, ZH Silks, LA Martinez, RA Donohoe, RJ Dyer, RB Woodruff, WH TI Direct infrared detection of the covalently ring linked His-Tyr structure in the active site of the heme-copper oxidases SO BIOCHEMISTRY LA English DT Article ID CYTOCHROME-C-OXIDASE; FTIR DIFFERENCE SPECTROSCOPY; PARACOCCUS-DENITRIFICANS; THERMUS-THERMOPHILUS; ESCHERICHIA-COLI; BOND-CLEAVAGE; MECHANISM; RESOLUTION; ACTIVATION; ANGSTROM AB Infrared spectroscopy, isotopic labeling ([N-15(delta,epsilon)]histidine and ring-deuterated tyrosine), synthetic model studies, and normal mode calculations are employed to search for the spectroscopic signatures of the unique, covalently linked (His N-epsilon-C-epsilon Tyr) biring structure in the heme-copper oxidases. The specific enzyme examined is the cytochrome bo(3) quinol oxidase of E. coli. Infrared features of histidine and tyrosine are identified in the frequency regions of imidazole and phenol ring stretching modes (1350-1650 cm(-1)) and C-H and N-H stretching modes as well as overtones and combinations (>3000 cm(-1)). Two of these, at ca. 1480 and 1550 cm(-1), and their combination tones between 30 10 and 3040 cm(-1), are definitively identified with the biring structure involving H284 and Y288 in the E. coli enzyme, Studies of a synthetic analogue of the H-Y structure, 4-methylimidazole covalently linked to p-cresol, show that a feature near 1540 cm-1 is unique to the biring structure and is absent from the infrared spectrum of 4-methylimidazole or p-cresol alone. This feature is readily detectable by infrared difference techniques, and offers a direct spectroscopic probe for potential radical production involving the H-Y structure in the O-2 reduction cycle of the oxidases. C1 Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Biosci Div, Szilard Resource, Natl Stable Isotope Resource, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Biosci Div, Michelson Resource, CSIC, Los Alamos, NM 87545 USA. Univ Illinois, Dept Chem, Urbana, IL 61801 USA. RP Woodruff, WH (reprint author), Los Alamos Natl Lab, Div Chem, POB 1663, Los Alamos, NM 87545 USA. FU NCRR NIH HHS [RR22031, P41 RR02231]; NIDDK NIH HHS [DK36263]; NIGMS NIH HHS [P01 GM068036] NR 28 TC 44 Z9 44 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD DEC 3 PY 2002 VL 41 IS 48 BP 14383 EP 14390 DI 10.1021/bi026370c PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 620CZ UT WOS:000179517000035 PM 12450405 ER PT J AU Ricci, P Lapenta, G Brackbill, JU AF Ricci, P Lapenta, G Brackbill, JU TI GEM reconnection challenge: Implicit kinetic simulations with the physical mass ratio SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID COLLISIONLESS MAGNETIC RECONNECTION; TRANSPORT; HYBRID; PLASMAS; MODEL AB [1] We extend kinetic simulations of the Geospace Environment Modeling (GEM) magnetic reconnection challenge [Birn et al., J. Geophys. Res., 106, 3715, 2001] to a physical mass ratio, using the implicit Particle-in-Cell (PIC) code CELESTE3D which allows the use of a coarser grid and a bigger time step. We compare results for three values of the mass ratio m(i)/m(e) = 25 (GEM challenge standard mass ratio), m(i)/m(e) = 180 and the physical mass ratio m(i)/m(e) = 1836. The results of the three simulations are compared and the scaling laws based on reconnection via nongyrotropic electron pressure are verified. C1 Politecn Torino, Dipartimento Energet, I-10129 Turin, Italy. Politecn Torino, Dipartimento Fis, Ist Nazl Fis Mat, Turin, Italy. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Ricci, P (reprint author), Politecn Torino, Dipartimento Energet, Corso Duca degli Abruzzi 24, I-10129 Turin, Italy. EM lapenta@lanl.gov; jub@lanl.gov OI Lapenta, Giovanni/0000-0002-3123-4024 NR 19 TC 40 Z9 41 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 3 PY 2002 VL 29 IS 23 AR 2088 DI 10.1029/2002GL015314 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 646YJ UT WOS:000181064000001 ER PT J AU Chapman, EG Shaw, WJ Easter, RC Bian, X Ghan, SJ AF Chapman, EG Shaw, WJ Easter, RC Bian, X Ghan, SJ TI Influence of wind speed averaging on estimates of dimethylsulfide emission fluxes SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE dimethylsulfide; air-sea gas exchange; surface fluxes; marine boundary layer; climate change; Monin-Obukhov similarity theory ID GENERAL-CIRCULATION MODEL; TROPOSPHERIC SULFUR CYCLE; SEA CO2 EXCHANGE; SULFATE AEROSOL; CLIMATE-MODEL; GAS-EXCHANGE; ATMOSPHERE; WATER AB [1] The effect of various wind speed averaging periods on calculated dimethylsulfide (DMS) emission fluxes is quantitatively assessed. A global climate model and an emission flux module were run in stand-alone mode for a full year. Twenty-minute instantaneous surface wind speeds and related variables generated by the climate model were archived, and corresponding 1-hour, 6-hour, daily, and monthly averaged quantities were calculated. These various time-averaged, model-derived quantities were used as inputs in the emission flux module, and DMS emissions were calculated using two expressions for the mass transfer velocity commonly used in atmospheric models [Liss and Merlivat, 1986; Nightingale et al., 2000]. Results indicate that the time period selected for averaging wind speeds can affect the magnitude of calculated DMS emission fluxes. A number of individual marine cells within the global grid show DMS emissions fluxes that are 10-60% higher when emissions are calculated using 20-min instantaneous model time step winds rather than monthly averaged wind speeds, and at some locations the differences exceed 200%. Many of these cells are located in the Southern Hemisphere where anthropogenic sulfur emissions are low and changes in oceanic DMS emissions may significantly affect calculated aerosol concentrations and aerosol radiative forcing. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Chapman, EG (reprint author), Pacific NW Natl Lab, POB 999,MSIN K9-30, Richland, WA 99352 USA. EM elaine.chapman@pnl.gov RI Chapman, Elaine/K-8756-2012; Ghan, Steven/H-4301-2011 OI Ghan, Steven/0000-0001-8355-8699 NR 35 TC 11 Z9 11 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 3 PY 2002 VL 107 IS D23 AR 4672 DI 10.1029/2001JD001564 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 646UU UT WOS:000181054600005 ER PT J AU Chen, HL Lin, SY Huang, YY Chiu, FC Liou, W Lin, JS AF Chen, HL Lin, SY Huang, YY Chiu, FC Liou, W Lin, JS TI Crystallization in the vesicle walls templated by dry-brush block copolymer/homopolymer blend SO MACROMOLECULES LA English DT Article ID SEMICRYSTALLINE DIBLOCK COPOLYMERS; ORDERED STRUCTURE; CONFINED CRYSTALLIZATION; POLYMER CRYSTALLIZATION; SELF-ORGANIZATION; PHASE STRUCTURES; HOMOPOLYMERS; POLYSTYRENE; KINETICS; MORPHOLOGIES AB We studied the crystallization behavior in a diblock copolymer/homopolymer blend system exhibiting "dry-brush" phase behavior in the melt. A nearly symmetric polyethylene oxide)-block-polybutadiene (PEO-b-PB) was blended with a PB homopolymer (h-PB) having approximately the same molecular weight as that of the PB block, thereby yielding the dry-brush blends wherein h-PB was localized in the PB microdomain, causing expansion of PB domain thickness without introducing transformation in microdomain morphology. Even though the lamellar identity of PEO domain retained throughout the blend composition, the lamellar units became increasingly isolated as characterized by the formations of cylindrical and spherical vesicles at high w(h-PB) compositions. Over the major composition range (w(h-PB) less than or equal to 0.7), crystallization of PEO blocks in the vesicle wall was able to take place at the undercooling comparable to that of PEO homopolymer, implying that the crystallization mechanism was analogous to the homopolymer crystallization initiated predominantly through heterogeneous nucleation followed by long-range crystal growth. At the compositions (w(h-PB) greater than or equal to 0.8) where most PEO lamellae formed shells of spherical vesicles in the melt, the crystallization was effectively confined within the individual vesicle, and it only occurred at very deep undercooling (DeltaT > 70 K). The corresponding isothermal crystallization followed the first-order kinetics prescribed by a nucleation-controlled crystallization wherein the crystallization started from homogeneous nuclei followed by essentially instantaneous crystal growth to fill the vesicle wall. In general, the confinement effect exerted by dry-brush blending was far less effective than the corresponding wet-brush blending. C1 Natl Tsing Hua Univ, Dept Chem Engn, Hsinchu 30013, Taiwan. Chang Gung Univ, Dept Chem & Mat Engn, Tao Yuan 333, Taiwan. Chang Gung Univ, Dept Anat, Tao Yuan 333, Taiwan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Chen, HL (reprint author), Natl Tsing Hua Univ, Dept Chem Engn, Hsinchu 30013, Taiwan. NR 46 TC 29 Z9 30 U1 1 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 3 PY 2002 VL 35 IS 25 BP 9434 EP 9440 DI 10.1021/ma020997l PG 7 WC Polymer Science SC Polymer Science GA 622AE UT WOS:000179623200028 ER PT J AU Hill, DE Lin, Y Rao, AM Allard, LF Sun, YP AF Hill, DE Lin, Y Rao, AM Allard, LF Sun, YP TI Functionalization of carbon nanotubes with polystyrene SO MACROMOLECULES LA English DT Article ID CHROMATOGRAPHIC PURIFICATION; COMPOSITE; POLYMER; DEFORMATION AB Single-walled and multiple-walled carbon nanotubes were functionalized with a polystyrene copolymer, poly(styrene-cop-(4-(4'-vinylphenyl)-3-oxabutanol)). The functionalization reaction conditions were designed for the esterification of the nanotube-bound carboxylic acids. The polymer-attached carbon nanotubes are soluble in common organic solvents, making it possible to characterize the samples using not only solid-state but also solution-based techniques. The solubility has also allowed an intimate mixing of the functionalized carbon nanotubes with polystyrene. Results from the characterization of the functionalized carbon nanotubes, including the chemical and thermal defunctionalizations of the soluble samples, and the fabrication of polystyrene-carbon nanotube composite thin films using a wet-casting method are presented and discussed. C1 Clemson Univ, Howard L Hunter Chem Lab, Dept Chem, Clemson, SC 29634 USA. Clemson Univ, Howard L Hunter Chem Lab, Ctr Adv Engn Fibers & Films, Clemson, SC 29634 USA. Clemson Univ, Kinard Lab, Dept Phys & Astron, Clemson, SC 29634 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Hill, DE (reprint author), Clemson Univ, Howard L Hunter Chem Lab, Dept Chem, Clemson, SC 29634 USA. NR 33 TC 309 Z9 320 U1 3 U2 53 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 3 PY 2002 VL 35 IS 25 BP 9466 EP 9471 DI 10.1021/ma020855r PG 6 WC Polymer Science SC Polymer Science GA 622AE UT WOS:000179623200032 ER PT J AU Goldstein, RZ Volkow, ND Chang, L Wang, GJ Fowler, JS Depue, RA Gur, RC AF Goldstein, RZ Volkow, ND Chang, L Wang, GJ Fowler, JS Depue, RA Gur, RC TI The orbitofrontal cortex in methamphetamine addiction: involvement in fear SO NEUROREPORT LA English DT Article DE constraint superfactor; drug addiction; fear; glucose metabolism; harm avoidance scale; inhibitory control; methamphetamine dependence; normalized/relative metabolism; orbitofrontal cortex; PET FDG; resting baseline; Tellegen's Multidimensional Personality Questionnaire ID COCAINE; PET; ASSOCIATION; DOPAMINE; DISEASE; ABUSERS AB We used Tellegen's Multidimensional Personality Questionnaire (MPQ) harm avoidance (fear) scale and the constraint superfactor as personality measures of inhibitory control and examined their association with glucose metabolism in the orbitofrontal gyrus at rest in 14 recently abstinent methamphetamine-dependent subjects and 22 comparison subjects. Higher MPQ scores were associated with higher relative orbitofrontal gyrus metabolism in the methamphetamine-dependent subjects. There was a tendency towards a negative association for the comparison subjects (test of coincidence of regression lines for the two subject groups: F = 3.3, df = 2,32; p = 0.051). These results suggest that the role of the orbitofrontal cortex in inhibitory control can be manifested in stable personality predispositions and further implicate this region in the core characteristics of drug addiction. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Cornell Univ, Dept Human Dev, Lab Neurobiol Personal & Emot, Ithaca, NY 14853 USA. Univ Penn, Med Ctr, Dept Psychiat, Brain Behav Lab, Philadelphia, PA 19104 USA. RP Goldstein, RZ (reprint author), Brookhaven Natl Lab, Bldg 490,POB 5000, Upton, NY 11973 USA. FU NCRR NIH HHS [M01 RR10710, M01 RR000425, M01 RR00425, M01 RR010710]; NIDA NIH HHS [1K23 DA15517-01, 1R01 DA12734, K20-DA00280, K23 DA015517, R01 DA006891, R01 DA012734] NR 18 TC 24 Z9 26 U1 1 U2 4 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0959-4965 J9 NEUROREPORT JI Neuroreport PD DEC 3 PY 2002 VL 13 IS 17 BP 2253 EP 2257 DI 10.1097/01.wnr0000044215.09266.bf PG 5 WC Neurosciences SC Neurosciences & Neurology GA 631KV UT WOS:000180167700017 PM 12488806 ER PT J AU Kreiss, HO Petersson, NA Ystrom, J AF Kreiss, HO Petersson, NA Ystrom, J TI Difference approximations for the second order wave equation SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE wave equation; stability; accuracy; embedded boundary ID MAXWELLS EQUATIONS AB Difference approximations are derived for the second order wave equation in one and two space dimensions, without first writing it as a first order system. Both the Dirichlet and the Neumann problems are treated for the one-dimensional case. Relations between the boundary error and the interior phase error are derived for a fully second order accurate discretization as well as a scheme that is fourth order accurate in the interior and second order accurate at the boundary. General two-dimensional domains are considered for the Dirichlet problem where the domain is embedded in a Cartesian grid and the boundary conditions are approximated by interpolation. A stable conservative scheme is derived where the time step is determined only by the interior discretization formula. Discretization cells cut by the boundary are treated implicitly, but the resulting scheme becomes explicit because the implicit dependence only is pointwise. Numerical examples are provided to verify the stability and accuracy of the proposed method. C1 Univ Calif Los Angeles, Dept Math, Los Angeles, CA 90024 USA. Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. Royal Inst Technol, Dept Numer Anal & Comp Sci, S-10044 Stockholm, Sweden. RP Kreiss, HO (reprint author), Univ Calif Los Angeles, Dept Math, Los Angeles, CA 90024 USA. NR 11 TC 59 Z9 60 U1 0 U2 6 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PD DEC 3 PY 2002 VL 40 IS 5 BP 1940 EP 1967 AR PII S0036142901397435 DI 10.1137/S0036142901397435 PG 28 WC Mathematics, Applied SC Mathematics GA 631MT UT WOS:000180172100015 ER PT J AU Curtis, PS Hanson, PJ Bolstad, P Barford, C Randolph, JC Schmid, HP Wilson, KB AF Curtis, PS Hanson, PJ Bolstad, P Barford, C Randolph, JC Schmid, HP Wilson, KB TI Biometric and eddy-covariance based estimates of annual carbon storage in five eastern North American deciduous forests SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article; Proceedings Paper CT 1st FLUXNET Synthesis Workshop CY JUN 11-14, 2000 CL MARSHALL, CALIFORNIA DE annual carbon storage; net ecosystem productivity; net ecosystem exchange; deciduous forests; AmeriFlux ID NET PRIMARY PRODUCTION; UPLAND OAK FOREST; NITROGEN MINERALIZATION; LONG-TERM; WATER-VAPOR; MIDLATITUDE FOREST; SOIL RESPIRATION; TALL VEGETATION; FINE ROOTS; DIOXIDE AB Quantifying net carbon (C) storage by forests is a necessary step in the validation of carbon sequestration estimates and in assessing the possible role of these ecosystems in offsetting fossil fuel emissions. In eastern North America, five sites were established in deciduous forests to provide measurements of net ecosystem CO2 exchange (NEE) using micro-meteorological methods, and measures of major carbon pools and fluxes, using a combination of forest mensurational, eco-physiological, and other biometric methods. The five study sites, part of the AmeriFlux network, ranged across 10degrees of latitude and 18degrees of longitude, but were all of similar age, canopy height, and stand basal area. Here we present a cross-site synthesis of annual carbon storage estimates, comparing meteorological and biometric approaches, and also comparing biometric estimates based on analyses of autotrophic carbon pools and heterotrophic carbon fluxes (net ecosystem production, NEP) versus those based on measurements of change in two major carbon pools (DeltaC). Annual above-ground net primary production (ANPP) varied nearly two-fold among sites and was strongly correlated with average annual temperature and with annual soil nitrogen mineralization (N-min). Estimates of NEP ranged from 0.7 Mg C per hectare per year in northern lower Michigan to 3.5 Mg C per hectare per year in central Indiana, and were also well correlated with N-min. There was less variation among sites in estimates of DeltaC (range, 1.8-3.2 Mg C per hectare per year). In general, DeltaC more closely matched NEE than did NEP, but there was no systematic pattern among sites in over- versus under-estimation of the biometric compared to the meteorologically based measures. Root and soil carbon dynamics were significant sources of uncertainty in our biometric measures and represent a prerequisite area of study needed for accurate estimates of forest carbon storage. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Ohio State Univ, Dept Ecol Evolut & Organismal Biol, Columbus, OH 43210 USA. NOAA, Oak Ridge, TN 37831 USA. Indiana Univ, Bloomington, IN 47405 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Minnesota, Minneapolis, MN 55455 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Curtis, PS (reprint author), Ohio State Univ, Dept Ecol Evolut & Organismal Biol, 1735 Neil Ave, Columbus, OH 43210 USA. RI Hanson, Paul J./D-8069-2011; Schmid, Hans Peter/I-1224-2012 OI Hanson, Paul J./0000-0001-7293-3561; Schmid, Hans Peter/0000-0001-9076-4466 NR 70 TC 232 Z9 257 U1 5 U2 75 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD DEC 2 PY 2002 VL 113 IS 1-4 BP 3 EP 19 AR PII S0168-1923(02)00099-0 DI 10.1016/S0168-1923(02)00099-0 PG 17 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 614KQ UT WOS:000179188300002 ER PT J AU Davidson, EA Savage, K Bolstad, P Clark, DA Curtis, PS Ellsworth, DS Hanson, PJ Law, BE Luo, Y Pregitzer, KS Randolph, JC Zak, D AF Davidson, EA Savage, K Bolstad, P Clark, DA Curtis, PS Ellsworth, DS Hanson, PJ Law, BE Luo, Y Pregitzer, KS Randolph, JC Zak, D TI Belowground carbon allocation in forests estimated from litterfall and IRGA-based soil respiration measurements SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article; Proceedings Paper CT 1st FLUXNET Synthesis Workshop CY JUN 11-14, 2000 CL MARSHALL, CALIFORNIA DE carbon dioxide (CO2); carbon cycling; forest ecosystems; forest soils; infrared gas analyzers; roots; soil carbon ID WATER-VAPOR EXCHANGE; ORGANIC-MATTER; SPATIAL VARIABILITY; TEMPERATE FOREST; CO2 ENRICHMENT; GLOBAL TREND; BEECH FOREST; FINE ROOTS; DYNAMICS; DIOXIDE AB Allocation of C to belowground plant structures is one of the most important, yet least well quantified fluxes of C in terrestrial ecosystems. In a literature review of mature forests worldwide, Raich and Nadelhoffer ( 1989) suggested that total belowground carbon allocation (TBCA) could be estimated from the difference between annual rates of soil respiration and abovearound litterfall. Here we analyze new measurements of soil respiration and litterfall, including data from the Ameriflux network. Our results generally agree with Raich and Nadelhoffer's previous work. A regression analysis of data from mature forests produced the following relationship: annual soil respiration = 287 + 2.80 x annual litterfall. This regression slope indicates that, on average, soil respiration is roughly three times aboveground litterfall-C, which further implies that TBCA is roughly twice annual aboveground litterfall-C. These inferences are based on the uncertain assumption of soil C stocks being at steady state. Nevertheless, changes in soil C would have to be very large to modify the conclusion that TBCA is generally much larger than litterfall. Among only mature temperate hardwood forests, however, the correlation between litterfall and soil respiration was poor, and the correlation among years for a single site was also poor. Therefore, the regression cannot be relied upon to provide accurate estimates of soil respiration or TBCA for individual sites. Moreover, interannual variation in TBCA, short-term changes in C stocks, or different temporal scales controlling leaf litter production and soil respiration may cause important deviations from the global average. The regression slope for data from young forests is steeper, possibly indicating proportionally greater TBCA, but the steady-state assumption is more problematic for young forests. This method for estimating TBCA may be most appropriate where interannual variation is averaged over several years of observations and where a near-steady-state assumption of soil, litter, and root C stocks is least problematic. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Woods Hole Res Ctr, Woods Hole, MA 02543 USA. Univ Michigan, Sch Nat Resources & Environm, Ann Arbor, MI 48109 USA. Indiana Univ, Sch Publ & Environm Affairs, Bloomington, IN 47405 USA. Michigan Technol Univ, Sch Forestry & Wood Prod, Houghton, MI 49931 USA. Univ Oklahoma, Dept Bot & Microbiol, Norman, OK 73019 USA. Oregon State Univ, Coll Forestry, Corvallis, OR 97331 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Duke Univ, Nicholas Sch Environm, Durham, NC 27708 USA. Ohio State Univ, Dept Ecol Evolut & Organismal Biol, Columbus, OH 43210 USA. Univ Missouri, Dept Biol, Miami, FL 33102 USA. Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. RP Davidson, EA (reprint author), Woods Hole Res Ctr, POB 296, Woods Hole, MA 02543 USA. RI Hanson, Paul J./D-8069-2011; Zak, Donald/C-6004-2012; Davidson, Eric/K-4984-2013; OI Hanson, Paul J./0000-0001-7293-3561; Law, Beverly/0000-0002-1605-1203; Davidson, Eric/0000-0002-8525-8697; Ellsworth, David/0000-0002-9699-2272 NR 36 TC 170 Z9 194 U1 12 U2 88 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD DEC 2 PY 2002 VL 113 IS 1-4 BP 39 EP 51 AR PII S0168-1923(02)00101-6 DI 10.1016/S0168-1923(02)00101-6 PG 13 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 614KQ UT WOS:000179188300004 ER PT J AU Law, BE Falge, E Gu, L Baldocchi, DD Bakwin, P Berbigier, P Davis, K Dolman, AJ Falk, M Fuentes, JD Goldstein, A Granier, A Grelle, A Hollinger, D Janssens, IA Jarvis, P Jensen, NO Katul, G Mahli, Y Matteucci, G Meyers, T Monson, R Munger, W Oechel, W Olson, R Pilegaard, K Paw, KT Thorgeirsson, H Valentini, R Verma, S Vesala, T Wilson, K Wofsy, S AF Law, BE Falge, E Gu, L Baldocchi, DD Bakwin, P Berbigier, P Davis, K Dolman, AJ Falk, M Fuentes, JD Goldstein, A Granier, A Grelle, A Hollinger, D Janssens, IA Jarvis, P Jensen, NO Katul, G Mahli, Y Matteucci, G Meyers, T Monson, R Munger, W Oechel, W Olson, R Pilegaard, K Paw, KT Thorgeirsson, H Valentini, R Verma, S Vesala, T Wilson, K Wofsy, S TI Environmental controls over carbon dioxide and water vapor exchange of terrestrial vegetation SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article; Proceedings Paper CT 1st FLUXNET Synthesis Workshop CY JUN 11-14, 2000 CL MARSHALL, CALIFORNIA DE gross ecosystem production; ecosystem respiration; net ecosystem exchange; carbon balancc; eddy covariance ID NET ECOSYSTEM EXCHANGE; PONDEROSA PINE FORESTS; LONG-TERM MEASUREMENTS; BLACK SPRUCE FOREST; DECIDUOUS FOREST; LEAF-AREA; SEASONAL-VARIATION; BOREAL FOREST; PRIMARY PRODUCTIVITY; PACIFIC-NORTHWEST AB The objective of this research was to compare seasonal and annual estimates of CO2 and water vapor exchange across sites in forests, grasslands, crops, and tundra that are part of an international network called FLUXNET, and to investigating the responses of vegetation to environmental variables. FLUXNETs goals are to understand the mechanisms controlling the exchanges of CO2, water vapor and energy across a spectrum of time and space scales, and to provide information for modeling of carbon and water cycling across regions and the globe. At a subset of sites, net carbon uptake (net ecosystem exchange, the net of photosynthesis and respiration) was greater under diffuse than under direct radiation conditions, perhaps because of a more efficient distribution of non-saturating light conditions for photosynthesis, lower vapor pressure deficit limitation to photosynthesis, and lower respiration associated with reduced temperature. The slope of the relation between monthly gross ecosystem production and evapotranspiration was similar between biomes. except for tundra vegetation, showing a strong linkage between carbon gain and water loss integrated over the year (slopes = 3.4 g CO2/kg H2O for grasslands, 3.2 for deciduous broadleaf forests, 3.1 for crops, 2.4 for evergreen conifers, and 1.5 for tundra vegetation). The ratio of annual ecosystem respiration to gross photosynthesis averaged 0.83, with lower values for grasslands, presumably because of less investment in respiring plant tissue compared with forests. Ecosystem respiration was weakly correlated with mean annual temperature across biomes, in spite of within site sensitivity over shorter temporal scales. Mean annual temperature and site water balance explained much of the variation in gross photosynthesis. Water availability limits leaf area index over the long-term, and inter-annual climate variability can limit carbon uptake below the potential of the leaf area present. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Oregon State Univ, Coll Forestry, Corvallis, OR 97331 USA. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Univ Nebraska, Dept Agr Meteorol, Lincoln, NE 68583 USA. Agr Res Inst, Dept Environm Res, IS-112 Reykjavik, Iceland. Riso Natl Lab, Plant Biol & Biogeochem Dept, DK-4000 Roskilde, Denmark. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. San Diego State Univ, Dept Biol, San Diego, CA 92182 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. Univ Colorado, Dept Environm Populat & Organism Biol, Boulder, CO 80309 USA. NOAA, ARL, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37831 USA. Univ Tuscia, Dept Forest Environm & Resources, I-01100 Viterbo, Italy. Univ Edinburgh, Inst Ecol & Resource Management, Edinburgh EH9 3JU, Midlothian, Scotland. Duke Univ, Sch Environm, Durham, NC 27708 USA. Riso Natl Lab, DK-4000 Roskilde, Denmark. Univ Edinburgh, Inst Ecol & Resource Management, Edinburgh EH9 3JU, Midlothian, Scotland. Univ Antwerp, Dept Biol, Wilrijk, Belgium. US Forest Serv, USDA, Durham, NH 03824 USA. Swedish Univ Agr Sci, Dept Ecol & Environm Res, S-75007 Uppsala, Sweden. Ctr Rech Nancy, Unite Ecophysiol Forestieres, Equipe Bioclimatol, F-54280 Seichamps, France. Univ Virginia, Dept Environm Sci, Charlottesville, VA 22903 USA. Univ Calif Davis, LAWR, Atmospher Sci Grp, Davis, CA 95616 USA. Alterra, NL-6700 AA Wageningen, Netherlands. Univ Minnesota, Dept Soil Water & Climate, St Paul, MN 55108 USA. INRA, Ctr Bordeaux, Unite Bioclimatol, F-33833 Villenave Dornon, France. NOAA, OAR, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Univ Calif Berkeley, ESPM, Berkeley, CA 94704 USA. Univ Bayreuth, D-95440 Bayreuth, Germany. RP Law, BE (reprint author), Oregon State Univ, Coll Forestry, 328 Richardson Hall, Corvallis, OR 97331 USA. RI Katul, Gabriel/A-7210-2008; Oechel, Walter/F-9361-2010; Goldstein, Allen/A-6857-2011; Valentini, Riccardo/D-1226-2010; Hollinger, David/G-7185-2012; Pilegaard, Kim/I-7137-2013; Vesala, Timo/C-3795-2017; Law, Beverly/G-3882-2010; Janssens, Ivan/P-1331-2014; Baldocchi, Dennis/A-1625-2009; Matteucci, Giorgio/N-3526-2015; Meyers, Tilden/C-6633-2016; Gu, Lianhong/H-8241-2014; OI Katul, Gabriel/0000-0001-9768-3693; Oechel, Walter/0000-0002-3504-026X; Goldstein, Allen/0000-0003-4014-4896; Valentini, Riccardo/0000-0002-6756-5634; Pilegaard, Kim/0000-0002-5169-5717; Vesala, Timo/0000-0002-4852-7464; Law, Beverly/0000-0002-1605-1203; Janssens, Ivan/0000-0002-5705-1787; Baldocchi, Dennis/0000-0003-3496-4919; Matteucci, Giorgio/0000-0002-4790-9540; Gu, Lianhong/0000-0001-5756-8738; Dolman, A.J./0000-0003-0099-0457 NR 94 TC 610 Z9 686 U1 32 U2 258 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD DEC 2 PY 2002 VL 113 IS 1-4 BP 97 EP 120 AR PII S0168-1923(02)00104-1 DI 10.1016/S0168-1923(02)00104-1 PG 24 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 614KQ UT WOS:000179188300007 ER PT J AU Jasinski, J Swider, W Washburn, J Liliental-Weber, Z Chaiken, A Nauka, K Gibson, GA Yang, CC AF Jasinski, J Swider, W Washburn, J Liliental-Weber, Z Chaiken, A Nauka, K Gibson, GA Yang, CC TI Crystal structure of kappa-In2Se3 SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; IN2SE3; FILMS; GROWTH AB Structural properties of single-phase films of kappa-In2Se3 and gamma-In2Se3 were investigated. Both films were polycrystalline but their microstructures differed considerably. The a-lattice parameter of kappa-In2Se3 has been measured. A comparison between these two materials indicates that kappa-In2Se3 has a significantly larger unit cell (Deltac=2.5+/-0.2% and Deltaa=13.5+/-0.5%) and a structure more similar to the alpha-phase of In2Se3. (C) 2002 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Hewlett Packard Corp, Palo Alto, CA 94304 USA. RP Jasinski, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 9 TC 38 Z9 38 U1 2 U2 17 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 DEC 2 PY 2002 VL 81 IS 23 BP 4356 EP 4358 DI 10.1063/1.1526925 PG 3 WC Physics, Applied SC Physics GA 619NG UT WOS:000179481900015 ER PT J AU Kent, PRC Hart, GLW Zunger, A AF Kent, PRC Hart, GLW Zunger, A TI Biaxial strain-modified valence and conduction band offsets of zinc-blende GaN, GaP, GaAs, InN, InP, and InAs, and optical bowing of strained epitaxial InGaN alloys SO APPLIED PHYSICS LETTERS LA English DT Article ID CHEMICAL TRENDS; II-VI; SEMICONDUCTORS; DISCONTINUITY; CDTE; HGTE AB Using density-functional calculations, we obtain the (001) biaxial strain dependence of the valence and conduction band energies of GaN, GaP, GaAs, InN, InP, and InAs. The results are fit to a convenient-to-use polynomial and the fits provided in tabular form. Using the calculated biaxial deformation potentials in large supercell empirical pseudopotential calculations, we demonstrate that epitaxial strain reduces the InGaN alloy bowing coefficient compared to relaxed bulk alloys. (C) 2002 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kent, PRC (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Kent, Paul/A-6756-2008; Zunger, Alex/A-6733-2013; OI Kent, Paul/0000-0001-5539-4017; Hart, Gus L. W./0000-0002-6149-9234 NR 22 TC 31 Z9 31 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 DEC 2 PY 2002 VL 81 IS 23 BP 4377 EP 4379 DI 10.1063/1.1524299 PG 3 WC Physics, Applied SC Physics GA 619NG UT WOS:000179481900022 ER PT J AU Giesbrecht, GR Gordon, JC Clark, DL Scott, BL Watkin, JG Young, KJ AF Giesbrecht, GR Gordon, JC Clark, DL Scott, BL Watkin, JG Young, KJ TI Salt-free synthesis of samarium-aluminum mixed-metal alkoxides: X-ray crystal structures of {[(i-Pr-O)(i-Bu)Al(mu-O-i-Pr)(2)Sm(O-i-Pr)(HO-i-Pr)](mu-O-i-Pr)}(2), [(THF)(2)Sm(O-t-Bu)(2)(mu-O-t-Bu)(2)Al(i-Bu)(2)], Sm(OAr)(3)(THF)(3) (Ar=2,4,6-Me3C6H2), [Nd(mu-OAr)(OAr)(2)(py)(2)](2) (Ar=2,4,6-Me3C6H2), and (ArO)(3)Sm[(mu-O-t-Bu)(2)Al-2(O-t-Bu)(4)] (Ar=2,6-i-Pr2C6H3) SO INORGANIC CHEMISTRY LA English DT Article ID SOL-GEL PROCESS; R =; MOLECULAR-STRUCTURES; TERT-BUTYLALUMINUM; COMPLEXES; REACTIVITY; COORDINATION; OXIDE; PRECURSORS; LIGANDS AB Reaction of equimolar quantities of Sm[N(SiMe3)(2)](3) and Al(i-Bu)(3) with 6 equiv of iso-propyl alcohol in toluene leads to the formation of the mixed-metal alkoxide complex {[(i-Pr-O)(i-Bu)Al(mu-O-i-Pr)(2)Sm(O-i-Pr)(HO-i-Pr)](mu-O-i-Pr)}(2) (1). An analogous reaction between 1:1 Sm[N(SiMe3)(2)](3)/Al(i-Bu)(3) and 6 equiv of tert-butyl alcohol, followed by addition of THF, produces the THF adduct [(THF)(2)Sm(O-t-BU)(2)(mu-O-t-BU)(2)Al(i-BU)(2)] (2). Compound I crystallizes in the space group P (1) over bar while 2 crystallizes in space group Cmcm. Cell parameters for 1: a = 11.028(2) Angstrom, b = 12.168(2) Angstrom, c = 12.879(2) Angstrom, alpha = 82.84(1)degrees, beta = 64.88(1)degrees, gamma = 70.80(1)degrees, Z = 1. Cell parameters for 2: a = 11.304(2) Angstrom, b = 22.429(4) Angstrom, c = 15.768(2) Angstrom, z = 4. Attempts to prepare the bulkier derivatives result in the formation of lanthanide aryloxide species only; reaction between equimolar amounts of Ln[N(SiMe3)(2)](3) (Ln = Sm, Nd) and Al(i-Bu)(3) with 6 equiv of HO-2,4,6-Me3C6H2, followed by the addition of THF or pyridine, yields the Lewis base adducts Sm(OAr)(3)(THF)(3) (3) and [Nd(mu-OAr)(OAr)(2)(PY)(2)](2) (4). Compound 3 crystallizes in the space group Pbca while 4 crystallizes in space group P2(1)/c. Cell parameters for 3: a = 16.5822(g) Angstrom, b = 15.5668(g) Angstrom, c 29.902(2) Angstrom, Z 8. Cell parameters for 4: = 13.4496(8) Angstrom, b = 20.034(1) Angstrom, c = 16.206(1) Angstrom, beta = 113.782(1)degrees, Z = 2. Reaction of A(2)(O-t-BU)(6) with [Sm(OAr)(3)](2) (Ar = 2,6-i-Pr2C6H3) yields the adduct (ArO)(3)-Sm[(mu-O-t-Bu)(2)Al-2(0-t-BU)(4)] (5), which crystallizes in the space group P2(1)/n. Cell parameters for 5: a 14.0960(7) Angstrom, b = 27.3037(15) Angstrom, c = 16.7893(g) Angstrom, beta = 92.216(1)degrees, Z = 4. C1 Los Alamos Natl Lab, Div Chem C, CSIC, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, NMT Div, NMT DO, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Glenn T Seaborg Inst Transactinium Sci, Los Alamos, NM 87545 USA. RP Watkin, JG (reprint author), Los Alamos Natl Lab, Div Chem C, CSIC, Mail Stop J514, Los Alamos, NM 87545 USA. RI Clark, David/A-9729-2011; Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 65 TC 23 Z9 23 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 2 PY 2002 VL 41 IS 24 BP 6372 EP 6379 DI 10.1021/ic0203116 PG 8 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 620NV UT WOS:000179540200031 PM 12444780 ER PT J AU Bordallo, HN Wang, X Hanif, KM Strouse, GF da Fonseca, RJM Sosman, LP Tavares, AD AF Bordallo, HN Wang, X Hanif, KM Strouse, GF da Fonseca, RJM Sosman, LP Tavares, AD TI Structure determination and a vibrational study for the hexagonal elpasolite Cs2NaGaF6 : Cr3+ SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID 2-PHOTON EXCITATION SPECTROSCOPY; OPTICAL SPECTROSCOPY; CR3+ IONS; CS2NAALF6; CRYSTALS; LUMINESCENCE AB Single crystals of 0.5% Cr3+-doped Cs2NaGaF6 were studied by means of x-ray diffraction and polarized Raman scattering. The crystal exhibits a unique stacking interaction, with a hexagonal structure with R (3) over barm symmetry. Polarized Raman spectra recorded at 16 and 300 K reveal sidebands that are ascribed to the local vibrational of the [CrF6] coordination unit, which differ markedly from those of the Cs2NaGaF6 host lattice. The results are compared to findings for other elpasolite lattices, and the room temperature luminescence quantum yields are discussed in terms of a delicate balance between electron-phonon strength and lattice distortion. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Hahn Meitner Inst Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. UERJ, Inst Fis, BR-20550 Rio De Janeiro, Brazil. RP Bordallo, HN (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Sosman, L/I-1549-2013; Bordallo, Heloisa/I-6836-2012 OI Bordallo, Heloisa/0000-0003-0750-0553 NR 22 TC 17 Z9 18 U1 3 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 2 PY 2002 VL 14 IS 47 BP 12383 EP 12389 AR PII S0953-8984(02)37388-0 DI 10.1088/0953-8984/14/47/312 PG 7 WC Physics, Condensed Matter SC Physics GA 634DC UT WOS:000180323900016 ER PT J AU Halas, S Durakiewicz, T AF Halas, S Durakiewicz, T TI Temperature dependence of the surface energy of mercury from 0 to 250 degrees C SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter AB The surface energy (SE) for mercury was calculated on the basis of the free electron model in which the electron density parameter, r(s), for bulk electrons was calculated from the density of mercury while the electron density parameter for surface electrons, r(ss), was assumed to be higher by a factor that is linearly dependent on temperature. Ideal agreement of calculated SE values with experimental data was attained for the temperatures 0-250 degreesC assuming that r(ss) = r(s) x 1.0021(T/100degreesC). C1 Marie Curie Sklodowska Univ, Inst Phys, Mass Spectrometry Lab, PL-20031 Lublin, Poland. Inst Vacuum Technol, PL-00241 Warsaw, Poland. Los Alamos Natl Lab, MST Grp 4, Los Alamos, NM 87545 USA. RP Halas, S (reprint author), Marie Curie Sklodowska Univ, Inst Phys, Mass Spectrometry Lab, Pl M Curie Sklodowskiej 1, PL-20031 Lublin, Poland. NR 5 TC 6 Z9 6 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 2 PY 2002 VL 14 IS 47 BP L735 EP L737 AR PII S0953-8984(02)52535-2 DI 10.1088/0953-8984/14/47/103 PG 3 WC Physics, Condensed Matter SC Physics GA 634DC UT WOS:000180323900007 ER PT J AU Bunce, G AF Bunce, G TI The first RHIC spin run SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT European Workshop on the QCD Structure of the Nucleon (QCD-N 02) CY APR 03-06, 2002 CL FERRARA, ITALY AB The RHIC spin program will probe the spin structure of the proton with polarized quarks and gluons by colliding beams of polarized protons at Brookhaven. The first collisions, at roots = 200 GeV, were recorded this year in December 2001 and January 2002. This report describes the first run, and our plans for the next five+ years, with planned runs at roots = 200 and 500 GeV, and luminosity L = 2 x 10(32) cm(-2) s(-1). C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Bunce, G (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 2 PY 2002 VL 711 BP 62C EP 68C AR PII S0375-9474(02)01195-8 PG 7 WC Physics, Nuclear SC Physics GA 614TF UT WOS:000179206200011 ER PT J AU Perdekamp, MG Ogawa, A Hasuko, K Lange, S Siegle, V AF Perdekamp, MG Ogawa, A Hasuko, K Lange, S Siegle, V TI Future transversity measurements at RHIC SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT European Workshop on the QCD Structure of the Nucleon (QCD-N 02) CY APR 03-06, 2002 CL FERRARA, ITALY ID SEMIINCLUSIVE PION ELECTROPRODUCTION; FRAGMENTATION FUNCTION; SPIN ASYMMETRIES; DISTRIBUTIONS; COLLISIONS; HADRON AB Recent experimental results from the HERMES collaboration at DESY and the SMC collaboration at CERN suggest that it may be possible to access nucleon transversity distributions through the measurement of transverse single spin asymmetries in semi-inclusive hard scattering processes. In this paper we review the prospects of studying transversity distributions in polarized, proton proton collsions at RHIC. To unfold transversity distributions from the observable single spin asymmetries the knowledge of novel fragmentation functions is necessary. We include a discussion of the measurement of the relevant fragmentation functions in e(+)e(-) annihilation at the KEK b-factory. C1 RIKEN BNL Res Ctr, Upton, NY USA. Penn State Univ, University Pk, PA 16802 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RIKEN, Wako, Saitama 3510198, Japan. Univ Frankfurt, D-6000 Frankfurt, Germany. RP Perdekamp, MG (reprint author), RIKEN BNL Res Ctr, Upton, NY USA. NR 28 TC 2 Z9 2 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 DEC 2 PY 2002 VL 711 BP 69C EP 75C AR PII S0375-9474(02)01196-X PG 7 WC Physics, Nuclear SC Physics GA 614TF UT WOS:000179206200012 ER PT J AU Radyushkin, AV AF Radyushkin, AV TI Hadron structure: the fundamental physics to access via GPDs SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT European Workshop on the QCD Structure of the Nucleon (QCD-N 02) CY APR 03-06, 2002 CL FERRARA, ITALY ID NONFORWARD PARTON DISTRIBUTIONS; VIRTUAL COMPTON-SCATTERING; EVOLUTION-EQUATIONS; FORM-FACTORS; QCD; ELECTROPRODUCTION AB An introductory review of generalized parton distributions (GPDs) is given. C1 Jefferson Lab, Theory Grp, Newport News, VA 23606 USA. Old Dominion Univ, Dept Phys, Norfolk, VA 23529 USA. Joint Inst Nucl Res Dubna, Theoret Phys Lab, Dubna, Russia. RP Radyushkin, AV (reprint author), Jefferson Lab, Theory Grp, Newport News, VA 23606 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 2 PY 2002 VL 711 BP 99C EP 108C AR PII S0375-9474(02)01192-2 PG 10 WC Physics, Nuclear SC Physics GA 614TF UT WOS:000179206200018 ER PT J AU Elouadrhiri, L AF Elouadrhiri, L TI Deeply virtual Compton scattering at Jefferson Lab, results and prospects SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT European Workshop on the QCD Structure of the Nucleon (QCD-N 02) CY APR 03-06, 2002 CL FERRARA, ITALY ID NUCLEON; MESONS AB Recent results from the Deeply Virtual Compton Scattering (DVCS) program at Jefferson Lab will be presented. Approved dedicated DVCS experiments at 6 GeV and plans for the 12 GeV upgrade will be discussed. C1 Jefferson Lab, Div Phys, Newport News, VA USA. RP Elouadrhiri, L (reprint author), Jefferson Lab, Div Phys, Newport News, VA USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 2 PY 2002 VL 711 BP 154C EP 159C AR PII S0375-9474(02)01207-1 PG 6 WC Physics, Nuclear SC Physics GA 614TF UT WOS:000179206200025 ER PT J AU Hwang, DS AF Hwang, DS TI Light-cone wavefunction representation of generalized parton distributions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT European Workshop on the QCD Structure of the Nucleon (QCD-N 02) CY APR 03-06, 2002 CL FERRARA, ITALY ID WAVE-FUNCTION REPRESENTATION; VIRTUAL COMPTON-SCATTERING; SPIN AB The matrix elements of local operators such as electromagnetic current, energy momentum tensor, angular momentum, and generalized parton distributions have exact representations in terms of light-cone Fock state wavefunctions of bound states such as hadrons. We present formulae which express the form factors and the generalized parton distributions in terms of the light-cone wavefunctions. C1 Sejong Univ, Dept Phys, Seoul 143747, South Korea. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Hwang, DS (reprint author), Sejong Univ, Dept Phys, Seoul 143747, South Korea. NR 9 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 2 PY 2002 VL 711 BP 194C EP 198C AR PII S0375-9474(02)01215-O PG 5 WC Physics, Nuclear SC Physics GA 614TF UT WOS:000179206200033 ER PT J AU Mecking, BA AF Mecking, BA TI Physics plans for CEBAF at 12 GeV SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT European Workshop on the QCD Structure of the Nucleon (QCD-N 02) CY APR 03-06, 2002 CL FERRARA, ITALY ID VIRTUAL COMPTON-SCATTERING; DISTRIBUTIONS; POLARIZATION; MESONS; QCD AB The Continuous Electron Beam Accelerator Facility, CEBAF, makes use of electron and photon beams with an energy up to 6 GeV to investigate the electromagnetic structure of mesons, nucleons, and nuclei. The physics motivation for upgrading the facility to a maximum energy of 12 GeV will be discussed. C1 Jefferson Lab, Div Phys, Newport News, VA USA. RP Mecking, BA (reprint author), Jefferson Lab, Div Phys, Newport News, VA USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 2 PY 2002 VL 711 BP 330C EP 335C AR PII S0375-9474(02)01237-X PG 6 WC Physics, Nuclear SC Physics GA 614TF UT WOS:000179206200055 ER PT J AU Chudakov, E AF Chudakov, E TI High-rate precision experiments SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT European Workshop on the QCD Structure of the Nucleon (QCD-N 02) CY APR 03-06, 2002 CL FERRARA, ITALY ID PHOTOTUBE RICH DETECTOR; ELECTRON MULTIPLIER GEM; LHCB EXPERIMENT; MICROMEGAS; PERFORMANCE; RESOLUTION; ACCELERATOR; CALORIMETER; FERMILAB; READOUT AB A new generation of experiments for studies of the nucleon structure with electromagnetic probes is under consideration by the physics community interested in hadron physics. One of the main goals of these projects is studying the Generalized Parton Distributions (GPD), which typically requires detecting several particles in the final state, high luminosity, large acceptance and good missing mass resolution of the spectrometers. The combination of these requirements is challenging and pushes the detectors involved to the limits. In this paper a review of the proposed experiments is presented and their feasibility is evaluated taking into account the recent progress of the detector technique. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Thomas Jefferson Natl Accelerator Facil, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 48 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 2 PY 2002 VL 711 BP 352C EP 360C AR PII S0375-9474(02)01240-X PG 9 WC Physics, Nuclear SC Physics GA 614TF UT WOS:000179206200058 ER PT J AU Reeves, S Billingsley, R Embery, G Lindsey, R AF Reeves, S Billingsley, R Embery, G Lindsey, R TI Mancos shale oil potential large on Jicarilla lands in new Mexico SO OIL & GAS JOURNAL LA English DT Article C1 Adv Resources Int Inc, Houston, TX USA. Adv Resources Int Inc, Denver, CO USA. Jicarilla Apache Indian Nation, Dulce, NM USA. US DOE, Tulsa, OK USA. RP Reeves, S (reprint author), Adv Resources Int Inc, Houston, TX USA. NR 8 TC 0 Z9 0 U1 1 U2 1 PU PENNWELL PUBL CO ENERGY GROUP PI TULSA PA 1421 S SHERIDAN RD PO BOX 1260, TULSA, OK 74101 USA SN 0030-1388 J9 OIL GAS J JI Oil Gas J. PD DEC 2 PY 2002 VL 100 IS 49 BP 42 EP + PG 7 WC Energy & Fuels; Engineering, Petroleum SC Energy & Fuels; Engineering GA 623RP UT WOS:000179716900008 ER PT J AU Bastea, S Esposito, R Lebowitz, JL Marra, R AF Bastea, S Esposito, R Lebowitz, JL Marra, R TI Hydrodynamics of binary fluid phase segregation SO PHYSICAL REVIEW LETTERS LA English DT Article ID SPINODAL DECOMPOSITION; MIXTURES AB Starting with the Vlasov-Boltzmann equation for a binary fluid mixture, we derive an equation for the velocity field u when the system is segregated into two phases (at low temperatures) with a sharp interface between them. u satisfies the incompressible Navier-Stokes equations together with a jump boundary condition for the pressure across the interface which, in turn, moves with a velocity given by the normal component of u. Numerical simulations of the Vlasov-Boltzmann equations for shear flows parallel and perpendicular to the interface in a phase segregated mixture support this analysis. We expect similar behavior in real fluid mixtures. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Aquila, Dipartimento Matemat, Rome, Italy. Ctr Ric Linceo Beniamino Segre, Rome, Italy. Rutgers State Univ, Dept Phys, New Brunswick, NJ 08903 USA. Rutgers State Univ, Dept Math, New Brunswick, NJ 08903 USA. Univ Roma Tor Vergata, Dipartimento Fis, I-00173 Rome, Italy. Univ Roma Tor Vergata, Unita INFM, I-00173 Rome, Italy. RP Bastea, S (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI Marra, Rossana/K-7677-2015; OI Marra, Rossana/0000-0002-9577-0248; Esposito, Raffaele/0000-0003-1744-4161 NR 18 TC 7 Z9 7 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 DEC 2 PY 2002 VL 89 IS 23 AR 235701 DI 10.1103/PhysRevLett.89.235701 PG 4 WC Physics, Multidisciplinary SC Physics GA 617LG UT WOS:000179362700032 PM 12485020 ER PT J AU Burns, CA Giura, P Said, A Shukla, A Vanko, G Tuel-Benckendorf, M Isaacs, ED Platzman, PM AF Burns, CA Giura, P Said, A Shukla, A Vanko, G Tuel-Benckendorf, M Isaacs, ED Platzman, PM TI Electronic interactions in the expanded metal compound Li-NH3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID LITHIUM-AMMONIA; ALKALI-METALS; PLASMON DISPERSION; LIQUID AB Inelastic x-ray scattering was used to measure the plasmon as a function of electron density in liquid lithium ammonia as well as the low temperature solid phase. As the electronic density is lowered, electronic correlation effects cause the random-phase approximation (RPA) to break down, requiring more advanced theoretical treatments. The deviation from RPA becomes greatest at the lowest electronic densities. We also see evidence for decreased electronic screening as shown by an increase in the strength of the pseudopotential at lower concentrations. Plasmon behavior in the solid is similar to that of the heavier alkali metals, but surprisingly different than in the liquid. C1 Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Argonne Natl Lab, Adv Photon Source, SRI,CAT, Argonne, IL 60439 USA. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Burns, CA (reprint author), Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. RI Shukla, Abhay/G-6753-2011; Vanko, Gyorgy/B-8176-2012; giura, paola/E-3841-2017 OI Vanko, Gyorgy/0000-0002-3095-6551; NR 18 TC 19 Z9 19 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 2 PY 2002 VL 89 IS 23 AR 236404 DI 10.1103/PhysRevLett.89.236404 PG 4 WC Physics, Multidisciplinary SC Physics GA 617LG UT WOS:000179362700037 PM 12485025 ER PT J AU Cai, SH Rashkeev, SN Pantelides, ST Sohlberg, K AF Cai, SH Rashkeev, SN Pantelides, ST Sohlberg, K TI Atomic scale mechanism of the transformation of gamma-alumina to theta-alumina SO PHYSICAL REVIEW LETTERS LA English DT Article ID TRANSITION ALUMINAS AB gamma-alumina is known to transform to theta-alumina and finally to alpha-alumina upon thermal treatment with a catastrophic loss of porosity and catalytic activity. First-principles calculations were performed to investigate the atomic scale mechanism of the gamma- to theta-alumina transformation. The transformation pathways between the two different forms have been mapped out and identified as a sequence of Al cation migrations. Different possible Al migration paths may be responsible for the experimentally observed formation of domains and twins in theta-alumina. The estimated temperature dependence of the conversion rate is in excellent agreement with the experimental transformation temperature. C1 Xiamen Univ, Dept Phys, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China. Drexel Univ, Dept Chem, Philadelphia, PA 19104 USA. Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Xiamen Univ, Dept Phys, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China. EM sohlbergk@drexel.edu RI Cai, SH/G-3334-2010 NR 16 TC 32 Z9 33 U1 0 U2 10 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 DEC 2 PY 2002 VL 89 IS 23 AR 235501 DI 10.1103/PhysRevLett.89.235501 PG 4 WC Physics, Multidisciplinary SC Physics GA 617LG UT WOS:000179362700028 PM 12485016 ER PT J AU Gai, Z Wu, B Pierce, JP Farnan, GA Shu, DJ Wang, M Zhang, ZY Shen, J AF Gai, Z Wu, B Pierce, JP Farnan, GA Shu, DJ Wang, M Zhang, ZY Shen, J TI Self-assembly of nanometer-scale magnetic dots with narrow size distributions on an insulating substrate SO PHYSICAL REVIEW LETTERS LA English DT Article ID GROWTH; SURFACES; NANOSTRUCTURES; ISLANDS AB The self-assembly of iron dots on the insulating surface of NaCl(001) is investigated experimentally and theoretically. Under proper growth conditions, nanometer-scale magnetic iron dots with remarkably narrow size distributions can be achieved in the absence of a wetting layer. Furthermore, both the vertical and lateral sizes of the dots can be tuned with the iron dosage without introducing apparent size broadening, even though the clustering is clearly in the strong coarsening regime. These observations are interpreted using a phenomenological mean-field theory, in which a coverage-dependent optimal dot size is selected by strain-mediated dot-dot interactions. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Peking Univ, Dept Phys, Beijing 100871, Peoples R China. Univ Texas, Dept Phys, Austin, TX 78712 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Chinese Acad Sci, Int Ctr Quantum Struct, Beijing 100080, Peoples R China. Nanjing Univ, Dept Phys, Nanjing 210093, Peoples R China. RP Gai, Z (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Wu, Biao/B-3329-2008; Gai, Zheng/B-5327-2012 OI Wu, Biao/0000-0001-9229-5894; Gai, Zheng/0000-0002-6099-4559 NR 19 TC 55 Z9 57 U1 1 U2 12 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 DEC 2 PY 2002 VL 89 IS 23 AR 235502 DI 10.1103/PhysRevLett.89.235502 PG 4 WC Physics, Multidisciplinary SC Physics GA 617LG UT WOS:000179362700029 PM 12485017 ER PT J AU Garofalo, AM Strait, EJ Johnson, LC La Haye, RJ Lazarus, EA Navratil, GA Okabayashi, M Scoville, JT Taylor, TS Turnbull, AD AF Garofalo, AM Strait, EJ Johnson, LC La Haye, RJ Lazarus, EA Navratil, GA Okabayashi, M Scoville, JT Taylor, TS Turnbull, AD TI Sustained stabilization of the resistive-wall mode by plasma rotation in the DIII-D tokamak SO PHYSICAL REVIEW LETTERS LA English DT Article ID ERROR-FIELD AB Values of the normalized plasma pressure up to twice the free-boundary stability limit predicted by ideal magnetohydrodynamic (MHD) theory have been sustained in the DIII-D tokamak. Long-wavelength modes are stabilized by the resistive wall and rapid plasma toroidal rotation. High rotation speed is maintained by minimization of nonaxisymmetric magnetic fields, overcoming a long-standing impediment [E. J. Strait et al., Phys. Rev. Lett. 74, 2483 (1995)]. The ideal-MHD pressure limit calculated with an ideal wall is observed as the operational limit to the normalized plasma pressure. C1 Gen Atom Co, San Diego, CA 92186 USA. Columbia Univ, New York, NY USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Garofalo, AM (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 16 TC 83 Z9 83 U1 0 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 DEC 2 PY 2002 VL 89 IS 23 AR 235001 DI 10.1103/PhysRevLett.89.235001 PG 4 WC Physics, Multidisciplinary SC Physics GA 617LG UT WOS:000179362700026 PM 12485014 ER PT J AU Kogan, VG AF Kogan, VG TI Free energy and torque for superconductors with different anisotropies of Hc2 and lambda SO PHYSICAL REVIEW LETTERS LA English DT Article ID MAGNETIZATION; LATTICE; MGB2 AB The free energy is evaluated for a uniaxial superconductor with the anisotropy of the upper critical field, gamma(H)=H-c2,H-a/H-c2,H-c, different from the anisotropy of the penetration depth gamma(lambda)=lambda(c)/lambda(a). With increasing difference between gamma(H) and gamma(lambda), the equilibrium orientation of the crystal relative to the applied field may shift from theta=pi/2 (theta is the angle between the field and the c axis) to lower angles and reach theta=0 for large enough gamma(H). These effects are expected to take place in MgB2. C1 Iowa State Univ, Ames Lab DOE, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Kogan, VG (reprint author), Iowa State Univ, Ames Lab DOE, Ames, IA 50011 USA. NR 18 TC 41 Z9 41 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 DEC 2 PY 2002 VL 89 IS 23 AR 237005 DI 10.1103/PhysRevLett.89.237005 PG 4 WC Physics, Multidisciplinary SC Physics GA 617LG UT WOS:000179362700045 PM 12485033 ER PT J AU Li, YL Lewellen, J Huang, ZR Sajaev, V Milton, SV AF Li, YL Lewellen, J Huang, ZR Sajaev, V Milton, SV TI Time-resolved phase measurement of a self-amplified free-electron laser SO PHYSICAL REVIEW LETTERS LA English DT Article ID GAIN; PULSES; FEL AB We report on the first time-resolved phase measurement on self-amplified spontaneous emission (SASE) free-electron laser (FEL) pulses. We observed that the spikes in the output of such free-electron laser pulses have an intrinsic positive chirp. We also observed that the energy chirp in the electron bunch mapped directly into the FEL output. Under certain conditions, the two chirps cancel each other. The experimental result was compared with simulations and interpreted with SASE theory. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Li, YL (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 16 TC 13 Z9 13 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 2 PY 2002 VL 89 IS 23 AR 234801 DI 10.1103/PhysRevLett.89.234801 PG 4 WC Physics, Multidisciplinary SC Physics GA 617LG UT WOS:000179362700025 PM 12485013 ER PT J AU Martin, PM Olsen, LC Johnston, JW Depoy, DM AF Martin, PM Olsen, LC Johnston, JW Depoy, DM TI Investigation of sputtered HfF4 films and application to interference filters for thermophotovoltaics SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 29th International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 2002 CL SAN DIEGO, CALIFORNIA SP AVS Sci & Technol Soc, Adv Surface Engn Div DE thermophotovoltaic; X-ray diffraction; HfF4 films AB The optical properties of sputter deposited hafnium fluoride films and their use in fabricating a front surface, interference filter for thermophotovoltaic energy conversion were investigated. In particular, HfF4 films were being considered for the low index component in a multilayer interference filter that will selectively transmit photons in the wavelength range of 1.0-2.4 mum, and strongly reflect all other wavelengths. Processes were developed for sputter depositing HfF4 films with an index of refraction between 1.5 and 1.6, and an extinction coefficient below 0.001 in the 1.0-2.4 mum wavelength range. All HfF4 coatings were deposited by RF reactive magnetron sputtering with pressed powder targets. Chamber pressure during depositions ranged from 0.27 to 1.33 Pa, and RF power ranged from 50 W (0.9 1 W/cm(2)) to 150 W (2.73 W/cm(2)). Deposition rates depended primarily on target power and ranged from 0.03 to 0.1 nm/s. All depositions were performed with Ar as the sputtering gas. Resputtering effects due to plasma and adatom bombardment and neutral Ar atoms reflected off the target played an important role in sputter deposition of hafnium fluoride. Film thickness and composition varied strongly with substrate distance from the target axis. Resputtering of growing films by energetic argon atoms also resulted in strongly absorptive, fluorine-deficient films on the substrate platform near the target axis. However, films became increasingly more stoichiometric and transmissive as one moves away from the target axis. The films were found to be amorphous or weakly crystalline. Nine-layer interference filters were fabricated utilizing HfF4 and an Si:H alloy for the low- and high-index components, respectively. Physisorbed water in the HfF4 layers and Si-H bond stretching were the primary sources of absorption between 1 and 12 mum wavelengths. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Lockheed Martin, Schenectady, NY USA. RP Martin, PM (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 10 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 2 PY 2002 VL 420 BP 8 EP 12 AR PII S0040-6090(02)00652-1 DI 10.1016/S0040-6090(02)00652-1 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 627FJ UT WOS:000179922500003 ER PT J AU He, P Hseuh, HC Todd, RJ AF He, P Hseuh, HC Todd, RJ TI Metallization of ceramic vacuum chambers for SNS ring injection kicker magnets SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 29th International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 2002 CL SAN DIEGO, CALIFORNIA SP AVS Sci & Technol Soc, Adv Surface Engn Div DE injection kicker; ceramic chamber; magnetron sputtering; TiN; titanium nitride ID DEPOSITION; PRESSURE AB Ceramic chambers will be used in the pulsed kicker magnets for the injection of H- into the US Spallation Neutron Source (SNS) accumulator ring. There are two reasons for using ceramic chambers in kickers: (1) to avoid shielding of a fast-changing external magnetic field by metallic chamber walls; and (2) to reduce heating due to eddy currents. The inner surfaces of the ceramic chambers will be coated with a conductive layer, possibly titanium (Ti) or copper (Cu) with a titanium nitride (TiN) overlayer, to reduce the beam coupling impedance and provide passage for beam image current. This paper describes the development of sputtering method for the 0.83 m long 16 cm inner diameter ceramic chambers. Coatings of Ti, Cu and TiN with thicknesses up to 10 mum were produced by means of DC magnetron sputtering. The difficulty of coating insulators was overcome with the introduction of an anode screen. Films with good adhesion, uniform longitudinal thickness, and conductivity were produced. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Collider Accelerator Dept, Upton, NY 11973 USA. RP Todd, RJ (reprint author), Brookhaven Natl Lab, Collider Accelerator Dept, Upton, NY 11973 USA. NR 5 TC 1 Z9 1 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 2 PY 2002 VL 420 BP 38 EP 42 AR PII S0040-6090(02)00661-2 DI 10.1016/S0040-6090(02)00661-2 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 627FJ UT WOS:000179922500008 ER PT J AU Jankowski, AF Hayes, JP Felter, TE Evans, C Nelson, AJ AF Jankowski, AF Hayes, JP Felter, TE Evans, C Nelson, AJ TI Sputter deposition of silicon-oxide coatings SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 29th International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 2002 CL SAN DIEGO, CALIFORNIA SP AVS Sci & Technol Soc, Adv Surface Engn Div DE fused quartz; X-ray photoelectron spectroscopy; silicon-oxide coatings ID ULTRAVIOLET AB Fused silica and Si-O-x coatings are of interest for use under high flux conditions of laser light. Si-O-x coatings are sputter deposited from silicon and fused quartz targets using planar magnetrons operated in the r.f. mode with a variable working-gas mixture of Argon-Oxygen. A series of coatings are prepared on optically flat, fused quartz substrates. Analysis of surface curvature reveals the deposition process conditions that minimize residual stress. Compressive stress levels that exceed 1.5 GPa can be reduced to less than 0.4 GPa for an optimum working-gas pressure. Characterization using Rutherford backscattering and X-ray photoelectron spectroscopy indicates that both the fused quartz and silicon targets can be used to sputter deposit coatings with the chemical bonding features of the fused-quartz substrate material. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Jankowski, AF (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 8 TC 4 Z9 4 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 2 PY 2002 VL 420 BP 43 EP 46 AR PII S0040-6090(02)00741-1 DI 10.1016/S0040-6090(02)00741-1 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 627FJ UT WOS:000179922500009 ER PT J AU Windisch, CF Ferris, KF Exarhos, GJ Sharma, SK AF Windisch, CF Ferris, KF Exarhos, GJ Sharma, SK TI Conducting spinel oxide films with infrared transparency SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 29th International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 2002 CL SAN DIEGO, CALIFORNIA SP AVS Sci & Technol Soc, Adv Surface Engn Div DE electrical conductivity; spinel oxide; infrared transparency ID NICKEL-COBALT OXIDES; SURFACE-COMPOSITION; SMALL-POLARON; MIXED OXIDES; THIN-FILMS; X-RAY; TRANSITION; REDUCTION; OXYGEN; CO3O4 AB Mixed transition metal spinel oxide (AB(2)O(4)) films deposited from solution or by means of magnetron sputtering are found to exhibit resistivities as low as 3.0 mOhm cm and optical transparency to wavelengths near 15 mum. These remarkable properties are achieved when metal cations selected from group VIII in the periodic table are resident in the spinel lattice. Both cation charge state and site occupancy significantly influence properties in these relatively high refractive index and chemically robust films. Post-deposition annealing of deposited films in air always led to decreased resistivity but little change in the optical transmission was seen. In order to verify the small polaron charge transport mechanism that drives the conductivity, Raman spectra and both van der Pauw and Seebeck measurements were acquired as a function of film temperature and cation composition. Results indicate the importance of cation disorder on the conductivity and along with results from electronic structure simulations suggest processing avenues to further tailor film properties. These include partial substitution of lithium for cations resident on the tetrahedral lattice sites and gross replacement of first row transition metal cations with those deeper in the periodic table. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Hawaii Inst Geophys & Planetol, Honolulu, HI USA. RP Exarhos, GJ (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 52 TC 40 Z9 43 U1 5 U2 28 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 2 PY 2002 VL 420 BP 89 EP 99 AR PII S0040-6090(02)00740-X DI 10.1016/S0040-6090(02)00740-X PG 11 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 627FJ UT WOS:000179922500016 ER PT J AU Jankowski, AF Hayes, JP AF Jankowski, AF Hayes, JP TI Ti-Cr-Al-O thin film resistors SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 29th International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 2002 CL SAN DIEGO, CALIFORNIA SP AVS Sci & Technol Soc, Adv Surface Engn Div DE electrical resistors; Rf sputtering; resistivity AB Thin films of Ti-Cr-Al-O are produced for use as an electrical resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O-2 Vertical resistivity values that range from 10(4) to 10(10) Omega-cm are measured for Ti-Cr-Al-O films. The film resistivity can be design selected through control of the target composition and the deposition parameters. The Ti-Cr-Al-O thin film resistor is found to be thermally stable unlike other metal-oxide films. (C) 2002 Elsevier Science B.V All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Jankowski, AF (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 15 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 2 PY 2002 VL 420 BP 487 EP 491 AR PII S0040-6090(02)00850-7 DI 10.1016/S0040-6090(02)00850-7 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 627FJ UT WOS:000179922500082 ER PT J AU Mateja, A Devedjiev, Y Krowarsch, D Longenecker, K Dauter, Z Otlewski, J Derewenda, ZS AF Mateja, A Devedjiev, Y Krowarsch, D Longenecker, K Dauter, Z Otlewski, J Derewenda, ZS TI The impact of Glu -> Ala and Glu -> Asp mutations on the crystallization properties of RhoGDI: the structure of RhoGDI at 1.3 angstrom resolution SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID RGS-LIKE DOMAIN; CRYSTAL-STRUCTURE; SURFACE RESIDUES; PDZ-RHOGEF; FAMILY; PURIFICATION; EXPRESSION; REFINEMENT; PROTEINS; COMPLEX AB It is hypothesized that surface residues with high conformational entropy, specifically lysines and glutamates, impede protein crystallization. In a previous study using a model system of Rho-specific guanine nucleotide dissociation inhibitor (RhoGDI), it was shown that mutating Lys residues to Ala results in enhanced crystallizability, particularly when clusters of lysines are targeted. It was also shown that one of these mutants formed crystals that yielded diffraction to 2.0 Angstrom, a significant improvement on the wild-type protein crystals. In the current paper, an analysis of the impact of surface mutations replacing Glu residues with Ala or Asp on the stability and crystallization properties of RhoGDI is presented. The Glu --> Ala (Asp) mutants are generally more likely to produce crystals of the protein than the wild-type and in one case the resulting crystals yielded a diffraction pattern to 1.2 Angstrom resolution. This occurs in spite of the fact that mutating surface Glu residues almost invariably affects the protein's stability, as illustrated by the reduced DeltaG between folded and unfolded forms measured by isothermal equilibrium denaturation. The present study strongly supports the notion that rational surface mutagenesis can be an effective tool in overcoming problems stemming from the protein's recalcitrance to crystallization and may also yield dramatic improvements in crystal quality. C1 Univ Virginia, Dept Mol Physiol & Biol Phys, Charlottesville, VA 22908 USA. Univ Wroclaw, Inst Biochem & Mol Biol, PL-50137 Wroclaw, Poland. Brookhaven Natl Lab, NCI, Macromol Crystallog Lab, Synchrotron Radiat Res Sect, Upton, NY 11973 USA. RP Derewenda, ZS (reprint author), Univ Virginia, Dept Mol Physiol & Biol Phys, Charlottesville, VA 22908 USA. RI Otlewski, Jacek/B-6340-2008 FU NIGMS NIH HHS [GM62615] NR 22 TC 64 Z9 66 U1 0 U2 3 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 DEC PY 2002 VL 58 BP 1983 EP 1991 DI 10.1107/S090744490201394X PN 12 PG 9 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 619GV UT WOS:000179468800003 PM 12454455 ER PT J AU Terwilliger, TC AF Terwilliger, TC TI Statistical density modification with non-crystallographic symmetry SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID RESOLUTION; PROTEIN AB Statistical density modification is a technique for phase improvement through a calculation of the posterior probability of the phases, given experimental phase information and expectations about features of the electron-density map. The technique can take advantage of both estimates of electron density in the map and uncertainties or probability distributions for those estimates. For crystals with non-crystallographic symmetry (NCS), this allows the use of the expected similarity of electron density at NCS-related points without requiring an implicit assumption that these regions are identical. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Terwilliger, TC (reprint author), Los Alamos Natl Lab, Mail Stop M888, Los Alamos, NM 87545 USA. RI Terwilliger, Thomas/K-4109-2012 OI Terwilliger, Thomas/0000-0001-6384-0320 NR 18 TC 30 Z9 34 U1 0 U2 2 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 DEC PY 2002 VL 58 BP 2082 EP 2086 DI 10.1107/S0907444902016360 PN 12 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 619GV UT WOS:000179468800016 PM 12454468 ER PT J AU Korolev, S Koroleva, O Petterson, K Gu, M Collart, F Dementieva, I Joachimiak, A AF Korolev, S Koroleva, O Petterson, K Gu, M Collart, F Dementieva, I Joachimiak, A TI Autotracing of Escherichia coli acetate CoA-transferase alpha-subunit structure using 3.4 angstrom MAD and 1.9 angstrom native data SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID CRYSTAL-STRUCTURE; PROTEIN; CRYSTALLOGRAPHY; REFINEMENT AB The automation of protein structure determination is an essential component for high-throughput structural analysis in protein X-ray crystallography and is a key element in structural genomics. This highly challenging undertaking relies at present on the availability of high-quality native and derivatized protein crystals diffracting to high or moderate resolution, respectively. Obtaining such crystals often requires significant effort. The present study demonstrates that phases obtained at low resolution (>3.0 Angstrom) from crystals of SeMet-labeled protein can be successfully used for automated structure determination. The crystal structure of acetate CoA-transferase alpha-subunit was solved using 3.4 Angstrom multi-wavelength anomalous dispersion data collected from a crystal containing SeMet-substituted protein and 1.9 Angstrom data collected from a native protein crystal. C1 Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. Argonne Natl Lab, Struct Biol Ctr, Argonne, IL 60439 USA. RP Joachimiak, A (reprint author), Argonne Natl Lab, Biosci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. FU NIGMS NIH HHS [GM62414, P50 GM062414, P50 GM062414-02] NR 28 TC 9 Z9 11 U1 0 U2 2 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 DEC PY 2002 VL 58 BP 2116 EP 2121 DI 10.1107/S0907444902017055 PN 12 PG 6 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 619GV UT WOS:000179468800021 PM 12454473 ER PT J AU Terwilliger, TC AF Terwilliger, TC TI Rapid automatic NCS identification using heavy-atom substructures SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID PROTEIN AB An important component of a fully automated system for structure solution and phase improvement through density modification is a capability for identification of non-crystallographic symmetry as early in the process as possible. Algorithms exist for finding NCS in heavy-atom sites, but currently require of the order of N-5 comparisons to be made, where N is the number of sites to be examined, including crystallographically related locations. A method described here based on considering only sets of sites that have common interatomic distances reduces the computational time by several orders of magnitude. Additionally, searches for proper symmetry allow the identification of NCS in cases where only one heavy atom is present per NCS copy. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Terwilliger, TC (reprint author), Los Alamos Natl Lab, Mail Stop M888, Los Alamos, NM 87545 USA. RI Terwilliger, Thomas/K-4109-2012 OI Terwilliger, Thomas/0000-0001-6384-0320 NR 12 TC 21 Z9 22 U1 0 U2 1 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 DEC PY 2002 VL 58 BP 2213 EP 2215 DI 10.1107/S0907444902016384 PN 12 PG 3 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 619GV UT WOS:000179468800052 PM 12454504 ER PT J AU Reddy, S AF Reddy, S TI Novel phase at high density and their role in the structure and evolution of neutron stars SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 42nd Cracow School of Theoretical Physics CY MAY 31-JUN 09, 2002 CL ZAKOPANE, POLAND ID SUPERCONDUCTING QUARK MATTER; COLOR-FLAVOR-LOCKING; NUCLEAR-MATTER; KAON CONDENSATION; SUPERNOVA CORES; FINITE-DENSITY; MESON MASS; CFL PHASE; QCD; TRANSITIONS AB We present a pedagogic discussion on the role of novel phases of dense baryonic matter in "neutron" stars. Qualitative aspects of the physics that drives phase transitions and some of its astrophysical consequences are discussed. Observable aspects of neutron star structure and early evolution of the newly born neutron star are discussed in some detail. C1 MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Reddy, S (reprint author), MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. NR 85 TC 72 Z9 72 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 DEC PY 2002 VL 33 IS 12 BP 4101 EP 4140 PG 40 WC Physics, Multidisciplinary SC Physics GA 633UE UT WOS:000180300200002 ER PT J AU Koch, V AF Koch, V TI Fluctuations in heavy ion collisions SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 42nd Cracow School of Theoretical Physics CY MAY 31-JUN 09, 2002 CL ZAKOPANE, POLAND ID BY-EVENT FLUCTUATIONS; QUARK-GLUON PLASMA; CHARGED-PARTICLE RATIO; QCD CRITICAL-POINT; ART.; THERMODYNAMICS; CONSERVATION; LATTICE; SIGNAL AB dThe physics of fluctuations in heavy ion collisions is discussed and a few examples for actual measurements are presented. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Koch, V (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 35 TC 2 Z9 2 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD DEC PY 2002 VL 33 IS 12 BP 4219 EP 4233 PG 15 WC Physics, Multidisciplinary SC Physics GA 633UE UT WOS:000180300200005 ER PT J AU Tranter, TJ Herbst, RS Todd, TA AF Tranter, TJ Herbst, RS Todd, TA TI Determination of a solid phase mass transfer coefficient for modeling an adsorption bed system using ammonium molybdophosphate-polyacrylonitrile (AMP-PAN) as a sorbent for the removal of Cs-137 from acidic nuclear waste solutions SO ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY LA English DT Article DE ammonium molybdophosphate; polyacrylonitrile; cesium-137; nuclear waste; adsorption; fixed bed AB Ammonium molybdophosphate (AMP) immobilized on a polyacrylonitrile (PAN) support is an engineered form of cesium selective sorbent material developed at the Czech Technical University in Prague. This material is being investigated as a sorbent for removing Cs-137 from Idaho National Engineering and Environmental Laboratory (INEEL) acidic sodium bearing waste (SBW) solution. As part of this study, a computer program to solve the partial differential equations (PDE's) for continuity and rate of exchange in a fixed bed system has been developed using numerical finite difference algorithms. These equations are solved iteratively in order to derive a mass transfer coefficient that agrees with the results of bench scale column experiments. This mass transfer coefficient is then applied in the PDE solutions to predict breakthrough behavior in a semi-scale column experiment. The model provided excellent agreement with the semi-scale data with a mass transfer coefficient of 0.0126 min(-1). C1 BBWI Inc, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RI Todd, Terry /O-4930-2016 OI Todd, Terry /0000-0003-1324-6950 NR 11 TC 7 Z9 7 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0929-5607 J9 ADSORPTION JI Adsorpt.-J. Int. Adsorpt. Soc. PD DEC PY 2002 VL 8 IS 4 BP 291 EP 299 DI 10.1023/A:1021533429787 PG 9 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 623LV UT WOS:000179705300004 ER PT J AU Prasad, S Christenson, T Dugger, M AF Prasad, S Christenson, T Dugger, M TI Tribological coatings for LIGA MEMS SO ADVANCED MATERIALS & PROCESSES LA English DT Article AB Plasma-enhanced chemical vapor deposition has been applied to coat micro-electromechanical systems fabricated by a microlithography-based process known by its acronym as LIGA. C1 Sandia Natl Labs, Mat & Proc Sci Ctr, Albuquerque, NM 87185 USA. RP Prasad, S (reprint author), Sandia Natl Labs, Mat & Proc Sci Ctr, MS 0889, Albuquerque, NM 87185 USA. NR 0 TC 3 Z9 3 U1 0 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 0882-7958 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD DEC PY 2002 VL 160 IS 12 BP 30 EP 33 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 625BC UT WOS:000179796100004 ER PT J AU Gallis, MA Rader, DJ Torczynski, JR AF Gallis, MA Rader, DJ Torczynski, JR TI Thermophoresis in rarefied gas flows SO AEROSOL SCIENCE AND TECHNOLOGY LA English DT Article ID PRESSURE PLASMA PROCESSOR; SMALL KNUDSEN NUMBERS; NEAR-WALL REGION; PARTICLE DEPOSITION; SPHERICAL-PARTICLE; BOLTZMANN-EQUATION; FORCE; WAFER AB Numerical calculations are presented for the thermophoretic force acting on a free-molecular, motionless, spherical particle suspended in a rarefied gas flow between parallel plates of unequal temperature. The rarefied gas flow is calculated with the direct simulation Monte Carlo (DSMC) method, which provides a time-averaged approximation to the local molecular velocity distribution at discrete locations between the plates. A force Green's function is used to calculate the thermophoretic force directly from the DSMC simulations for the molecular velocity distribution, with the underlying assumption that the particle does not influence the molecular velocity distribution. Perfect accommodation of energy and momentum is assumed at all solid/gas boundaries. Earlier work for monatomic gases (helium and argon) is reviewed, and new calculations for a diatomic gas (nitrogen) are presented. Gas heat flux and particle thermophoretic forces for argon, helium, and nitrogen are given for a 0.01 m spacing between plates held at 263 and 283 K over a pressure range from 0.1 to 1000 mTorr (0.01333-133.3 Pa). A simple, approximate expression is introduced that can be used to correlate the thermophoretic force calculations accurately over a wide range of pressures, corresponding to a wide range of Knudsen numbers (ratio of the gas mean free path to the interplate separation). C1 Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. RP Rader, DJ (reprint author), Sandia Natl Labs, Engn Sci Ctr, POB 5800, Albuquerque, NM 87185 USA. NR 35 TC 17 Z9 17 U1 0 U2 6 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0278-6826 J9 AEROSOL SCI TECH JI Aerosol Sci. Technol. PD DEC PY 2002 VL 36 IS 12 BP 1099 EP 1117 DI 10.1080/02786820290092168 PG 19 WC Engineering, Chemical; Engineering, Mechanical; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 623MF UT WOS:000179706600002 ER PT J AU Hritzko, BJ Xie, Y Wooley, RJ Wang, NHL AF Hritzko, BJ Xie, Y Wooley, RJ Wang, NHL TI Standing-wave design of tandem SMB for linear multicomponent systems SO AICHE JOURNAL LA English DT Article ID SIMULATED MOVING-BED; COUNTERCURRENT ADSORPTION SEPARATION; ROBUST DESIGN; EQUILIBRIUM-THEORY; CONFIGURATIONS 4+4; MASS-TRANSFER; CHROMATOGRAPHY; ADSORBER; GLUCOSE; UNIT AB The standing-wave design was extended to achieve any desired split of mixtures containing three or more components in a single-ling and a tandem two-ring simulated moving bed (SMB). Mass-transfer effects were considered in the design for nonideal systems. The separation of a four-component mixture of glucose, Xylose, acetic acid and sulfuric acid was chosen to illustrate the design method. Rate-model simulations confirmed that the standing-wave design method could guarantee high purity and high yield. If all the components in a ternary mixture need to be recovered with high purity and high yield, the easier separation should be performed in the first ling of a tandem SMB to achieve the lowest desorbent consumption and the highest product concentration. If only the intermediate component needs to be recovered in high purity, one of the impurities should be allowed to distribute between the two product polls in the first ling to achieve a lower desorbent consumption and a higher product concentration. These strategies also apply to the separation of a mixture containing more than three components. C1 Purdue Univ, Sch Chem Engn, W Lafayette, IN 47907 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Purdue Univ, Sch Chem Engn, W Lafayette, IN 47907 USA. RP Wang, NHL (reprint author), Purdue Univ, Sch Chem Engn, W Lafayette, IN 47907 USA. NR 57 TC 58 Z9 58 U1 1 U2 10 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 3 PARK AVE, NEW YORK, NY 10016-5901 USA SN 0001-1541 J9 AICHE J JI AICHE J. PD DEC PY 2002 VL 48 IS 12 BP 2769 EP 2787 DI 10.1002/aic.690481207 PG 19 WC Engineering, Chemical SC Engineering GA 626DX UT WOS:000179858000006 ER PT J AU Benioff, P AF Benioff, P TI The representation of numbers in quantum mechanics SO ALGORITHMICA LA English DT Article DE quantum computers; rational numbers; integers; natural numbers; operations; number theory axioms; efficient implementability ID DECOHERENCE-FREE SUBSPACES; MULTIPLE-QUBIT ERRORS; COMPUTATION; COMPUTERS; UNIVERSAL; NETWORKS AB Earlier work on modular arithmetic of k-ary representations of length L of the natural numbers in quantum mechanics is extended here to k-ary representations of all natural numbers, and to integers and rational numbers. Since the length L is indeterminate, representations of states and operators using creation and annihilation operators for bosons and fermions are defined. Emphasis is on definitions and properties of operators corresponding to the basic operations whose properties are given by the axioms for each type of number. The importance of the requirement of efficient implementability for physical models of the axioms is emphasized. Based on this, successor operations for each value of j corresponding to +k(j-1) are defined. It follows from the efficient implementability of these successors, which is the case for all computers, that implementation of the addition and multiplication operators, which are defined in terms of polynomially many iterations of the successors, should be efficient. This is not the case for definitions based on just the successor for j = 1. This is the only successor defined in the usual axioms of arithmetic. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Benioff, P (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 44 TC 4 Z9 4 U1 1 U2 1 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0178-4617 J9 ALGORITHMICA JI Algorithmica PD DEC PY 2002 VL 34 IS 4 BP 529 EP 559 DI 10.1007/s00453-002-0982-5 PG 31 WC Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA 605AQ UT WOS:000178653600014 ER PT J AU Anderson, RA Martin, JE AF Anderson, RA Martin, JE TI Energy balance problems in systems of induced and permanent electric and magnetic dipoles SO AMERICAN JOURNAL OF PHYSICS LA English DT Article AB There are many problems where a detailed understanding of the interaction energy of systems of dipoles is needed, including electrorheological and magnetorheological fluids, ferrofluids, magnetic composites, and dielectrics. We have constructed soluble microscopic problems involving electric and magnetic dipoles to investigate energy balance, and have come to some understanding of the proper form of the dipolar free energy in aggregations of induced or permanent dipoles and mixtures thereof. The resulting equations clarify misconceptions sometimes found in the literature, and lead to greater intuition about the subtle aspects of the dipolar interactions. We discuss the application of these equations to dipole simulations to extract the dipole energy and material dielectric constant. (C) 2002 American Association of Physics Teachers. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Anderson, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 5 Z9 5 U1 0 U2 6 PU AMER ASSOC PHYSICS TEACHERS AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD DEC PY 2002 VL 70 IS 12 BP 1194 EP 1204 DI 10.1119/1.1507793 PG 11 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 619WW UT WOS:000179501300004 ER PT J AU Sattler, FR Schroeder, ET Dube, MP Jaque, SV Martinez, C Blanche, PJ Azen, S Krauss, RM AF Sattler, FR Schroeder, ET Dube, MP Jaque, SV Martinez, C Blanche, PJ Azen, S Krauss, RM TI Metabolic effects of nandrolone decanoate and resistance training in men with HIV SO AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM LA English DT Article DE anabolic steroids; lipoprotein(a); androgen therapy; insulin resistance; high-density lipoprotein cholesterol; low-density lipoprotein cholesterol; serum triglycerides ID DENSITY-LIPOPROTEIN PARTICLES; CORONARY-ARTERY DISEASE; HUMAN-IMMUNODEFICIENCY-VIRUS; SERUM-LIPID LEVELS; BODY-COMPOSITION; MYOCARDIAL-INFARCTION; INSULIN-RESISTANCE; TESTOSTERONE TREATMENT; CARDIOVASCULAR RISK; SUBCLASS PATTERNS AB Thirty human immunodeficiency virus (HIV)-infected men were randomized to a high dose of nandrolone decanoate weekly (group 1) or nandrolone plus resistance training (group 2) for 12 wk. For the two groups, nandrolone had no significant effects on total cholesterol, LDL cholesterol, LDL phenotype, or fasting triglycerides, although triglycerides decreased by 66 +/- 124 mg/dl for the entire population (P = 0.01). Group 2 subjects had a favorable increase of 5.2 +/- 7.7Angstrom in LDL particle size (P = 0.03), whereas there was no change in group 1. Lipoprotein( a) decreased by 7.3 +/- 6.8 mg/dl for group 1 (P = 0.002) and by 6.9 +/- 8.1 for group 2 (P = 0.013). However, HDL cholesterol decreased by 8.7 +/- 7.4 mg/dl for group 1 (P < 0.001) and by 10.6 +/- 5.9 for group 2 (P < 0.001). Percentages of HDL2b (9.7-12 nm) and HDL2a (8.8-9.7 nm) subfractions decreased similarly for the two groups, whereas HDL3a (8.2-8.8 nm) and HDL3b (7.8-8.2 nm) increased in the groups during study therapy (P less than or equal to 0.02 for all comparisons). There was no evidence of a decreased insulin sensitivity in either group, whereas fasting glucose, fasting insulin, and homeostasis model assessment improved in group 2 (P < 0.05). These metabolic effects were favorable (other than for HDL), but changes were generally transient (except for HDL in group 2), with measurements returning to baseline 2 mo after the interventions were completed. C1 Univ So Calif, Keck Sch Med, Dept Med, Los Angeles, CA 90033 USA. Univ So Calif, Keck Sch Med, Dept Biokinesiol & Phys Therapy, Los Angeles, CA 90033 USA. Univ So Calif, Keck Sch Med, Dept Biometry, Los Angeles, CA 90033 USA. Lawrence Berkeley Lab, Div Life Sci, Los Angeles, CA 90033 USA. RP Sattler, FR (reprint author), 1300 N Mission Rd, Los Angeles, CA 90033 USA. FU NCRR NIH HHS [MOI RR-43]; NHLBI NIH HHS [HL-184573]; NIDDK NIH HHS [DK-49308] NR 60 TC 21 Z9 21 U1 0 U2 0 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0193-1849 J9 AM J PHYSIOL-ENDOC M JI Am. J. Physiol.-Endocrinol. Metab. PD DEC PY 2002 VL 283 IS 6 BP E1214 EP E1222 DI 10.1152/ajpendo.00189.2002 PG 9 WC Endocrinology & Metabolism; Physiology SC Endocrinology & Metabolism; Physiology GA 612MP UT WOS:000179080300014 PM 12388173 ER PT J AU Baur, K Brennan, S Pianetta, P Opila, R AF Baur, K Brennan, S Pianetta, P Opila, R TI Looking at trace impurities on silicon wafers with synchrotron radiation SO ANALYTICAL CHEMISTRY LA English DT Article ID RAY-FLUORESCENCE SPECTROSCOPY; TOTAL-REFLECTION; METAL CONTAMINATION; X-RAYS; SCATTERING AB Because even very low levels of metal impurities can seriously degrade silicon integrated circuits, extremely sensitive methods must be developed to improve wafer cleaning. C1 Stanford Univ, Dept Elect Engn, Stanford, CA 94305 USA. Univ Delaware, Dept Mat Sci & Engn, Newark, DE 19716 USA. SSRL, Stanford, CA USA. RP Baur, K (reprint author), 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. NR 26 TC 6 Z9 6 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 1 PY 2002 VL 74 IS 23 BP 608A EP 616A DI 10.1021/ac022159v PG 9 WC Chemistry, Analytical SC Chemistry GA 621YC UT WOS:000179617700002 PM 12498179 ER PT J AU Miyabe, K Guiochon, G AF Miyabe, K Guiochon, G TI Thermodynamic interpretation of retention equilibrium in reversed-phase liquid chromatography based on enthalpy-entropy compensation SO ANALYTICAL CHEMISTRY LA English DT Article ID SURFACE-DIFFUSION; BONDED PHASES; MOBILE-PHASE; SOLID CHROMATOGRAPHY; PERFORMANCE; TEMPERATURE; BEHAVIOR; WATER; DEPENDENCE; PACKINGS AB The fundamentals of the retention equilibrium in reversed-phase liquid chromatography (RPLC) are studied on the basis of enthalpy-entropy compensation (EEC). First, retention data were acquired and the influence of the nature of the compounds, organic solvent modifier, and temperature on these data was assessed. Then, the data were analyzed according to the four different methods proposed by Krug et al., and an EEC was formally established. Linear correlations were observed between the logarithm of the adsorption equilibrium constants under the different RPLC conditions, suggesting linear free energy relationships (LFERs). Finally, the variations of the retentions with the experimental conditions are shown to be quantitatively explained by a new model based on EEC. Ibis model affords a comprehensive interpretation of the variations of retention originating from changes of either one parameter alone or several simultaneously. The slope and intercept of the LFER that relates two equilibrium systems are accounted for by the new model. The parameters of this model are the changes of enthalpy and entropy associated with the retention, the compensation temperatures, and the experimental conditions. C1 Toyama Univ, Fac Educ, Toyama 9308555, Japan. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Toyama Univ, Fac Educ, 3190 Gofuku, Toyama 9308555, Japan. NR 45 TC 18 Z9 18 U1 1 U2 6 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 DEC 1 PY 2002 VL 74 IS 23 BP 5982 EP 5992 DI 10.1021/ac0202233 PG 11 WC Chemistry, Analytical SC Chemistry GA 621YC UT WOS:000179617700016 PM 12498193 ER PT J AU Tamborini, G Phinney, D Bildstein, O Betti, M AF Tamborini, G Phinney, D Bildstein, O Betti, M TI Oxygen isotopic measurements by secondary ion mass spectrometry in uranium oxide microparticles: A nuclear forensic diagnostic SO ANALYTICAL CHEMISTRY LA English DT Article ID HIGH-PRECISION; PARTICLES; RATIOS; MICROANALYSIS; MICROPROBE; PLUTONIUM; MINERALS; SIMS AB To exploit oxygen isotopic measurement by SIMS as a diagnostic tool in nuclear forensics, the magnitude and reproducibility of O-isotope instrumental mass discrimination for O-isotope standards in the SIMS laboratory at the Institute for Transuranium Elements has been evaluated. Tests for matrix-dependent discrimination effects on three different O-isotope standards with substantially different matrix compositions have been performed. The results were checked by an interlaboratory comparison of O-isotope discrimination with those obtained in the SIMS laboratory at the Lawrence Livermore National Laboratory on two standards. The results from the two laboratories are in very good agreement, indicating statistically indistinguishable instrumental mass discrimination factors for O-18/O-16 ratios on the Cameca 6f and 3f, when the analyses are performed under the experimental conditions described. The 2sigma(mean) uncertainties of these factors are in the range of 0.3-0.9%. In accordance with the tested methodology, O-isotope compositions were measured in three particulate uranium oxide samples of nuclear forensics interest. C1 European Commiss, Joint Res Ctr, Inst Transuranium Elements, D-76125 Karlsruhe, Germany. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Tamborini, G (reprint author), European Commiss, Joint Res Ctr, Inst Transuranium Elements, POB 2340, D-76125 Karlsruhe, Germany. NR 28 TC 22 Z9 23 U1 3 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 1 PY 2002 VL 74 IS 23 BP 6098 EP 6101 DI 10.1021/ac0259515 PG 4 WC Chemistry, Analytical SC Chemistry GA 621YC UT WOS:000179617700030 PM 12498207 ER PT J AU Navar, J Mendez, E Dale, V AF Navar, J Mendez, E Dale, V TI Estimating stand biomass in the Tamaulipan thornscrub of northeastern Mexico SO ANNALS OF FOREST SCIENCE LA English DT Article DE seemingly unrelated linear regressions ID FOREST INVENTORY DATA; BELOW-GROUND BIOMASS; ROOT BIOMASS; LEVEL; TREE AB This paper presents information on below and aboveground standing biomass measurements and estimates using quadrat attributes in the Tamaulipan thornscrub of northeastern Mexico. Biomass components (i.e., leaves, branches, stem, and roots) were measured in 55 (5 m x 5 m) quadrats across northeastern Mexico. Total aboveground standing biomass was estimated on a per ha basis using six equations from two additive procedures, and contrasted against two conventional sets of equations. The results indicated that total standing weighted biomass averages 60.31 +/- 12.24 Mg ha(-1), composed of leaf (2.51 +/- 0.47 Mg ha(-1)), branch (24.44 +/- 4.88 Mg ha(-1)), stem (9.80 +/- 2.62 Mg ha(-1)), and root (23.56 +/- 4.25 Mg ha(-1)) biomass. The additive equations developed in seemingly unrelated linear regression that use quadrat attributes provided unbiased biomass estimates within the range of precision reported by conventional procedures. The additive equations are recommended for use in estimating total stand biomass for several land management issues. C1 UANL, Fac Ciencias Forestales, Monterrey 67700, NL, Mexico. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Navar, J (reprint author), UANL, Fac Ciencias Forestales, Km 145 Carretera Nacl Linares, Monterrey 67700, NL, Mexico. RI Dale, Virginia/B-6023-2009 NR 40 TC 15 Z9 18 U1 1 U2 2 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1286-4560 J9 ANN FOR SCI JI Ann. For. Sci. PD DEC PY 2002 VL 59 IS 8 BP 813 EP 821 DI 10.1051/forest:2002079 PG 9 WC Forestry SC Forestry GA 634NG UT WOS:000180346500002 ER PT J AU Coker, PR Smith, KL Hugh-Jones, ME AF Coker, PR Smith, KL Hugh-Jones, ME TI Antimicrobial susceptibilities of diverse Bacillus anthracis isolates SO ANTIMICROBIAL AGENTS AND CHEMOTHERAPY LA English DT Article AB A test of 25 genetically diverse isolates of Bacillus anthracis was conducted to determine their susceptibility to seven clinically relevant antimicrobial agents. Etest strips (AB BIODISK, Solna, Sweden) were used to measure the MICs for the isolates. Using the National Committee for Clinical Laboratory Standards MIC breakpoints for staphylococci, three isolates were found to be resistant to penicillin and five were found to be resistant to cefuroxime. The penicillin-resistant isolates were negative for beta-lactamase production. Continued surveillance of B. anthracis field isolates is recommended to monitor antimicrobial susceptibility. C1 Louisiana State Univ, Sch Vet Med, Dept Pathobiol Sci, Baton Rouge, LA 70803 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Coker, PR (reprint author), Louisiana State Univ, Sch Vet Med, Dept Pathobiol Sci, Baton Rouge, LA 70803 USA. NR 10 TC 29 Z9 32 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0066-4804 J9 ANTIMICROB AGENTS CH JI Antimicrob. Agents Chemother. PD DEC PY 2002 VL 46 IS 12 BP 3843 EP 3845 DI 10.1128/AAC.46.12.3843-3845.2002 PG 3 WC Microbiology; Pharmacology & Pharmacy SC Microbiology; Pharmacology & Pharmacy GA 617TB UT WOS:000179376000023 PM 12435686 ER PT J AU Roh, Y Liu, SV Li, GS Huang, HS Phelps, TJ Zhou, JZ AF Roh, Y Liu, SV Li, GS Huang, HS Phelps, TJ Zhou, JZ TI Isolation and characterization of metal-reducing Thermoanaerobacter strains from deep subsurface environments of the Piceance Basin, Colorado SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SHEWANELLA-PUTREFACIENS MR-1; ORGANIC-CARBON OXIDATION; BANDED IRON-FORMATIONS; SP-NOV; DISSIMILATORY REDUCTION; MICROBIAL REDUCTION; FE(III)-REDUCING BACTERIA; ELECTRON-ACCEPTORS; FE(III) REDUCTION; GEN-NOV AB Five bacterial strains were isolated from anaerobic enrichment cultures that had originated from inoculations with samples collected from the deep subsurface environments of the millions-of-years-old, geologically and hydrologically isolated Piceance Basin in Colorado. Small-subunit rRNA gene-based analyses indicated that all of these bacteria were closely related to Thermoanaerobacter ethanolicus, with similarities of 99.4 to 99.5%. Three isolates (X513, X514, and X561) from the five bacterial strains were used to examine physiological characteristics. These thermophilic bacteria were able to use acetate, glucose, hydrogen, lactate, pyruvate, succinate, and xylose as electron donors while reducing Fe(III), cobalt(III), chromium(VI), manganese(IV), and uranium(VI) at 60degreesC. One of the isolates (X514) was also able to utilize hydrogen as an electron donor for Fe(III) reduction. These bacteria exhibited diverse mineral precipitation capabilities, including the formation of magnetite (Fe3O4), siderite (FeCO3), rhodochrosite (MnCO3), and uraninite (UO2). The gas composition of the incubation headspace and the ionic composition of the incubation medium exerted profound influences on the types of minerals formed. The susceptibility of the thermophilic Fe (III)-reducing cultures to metabolic inhibitors specific for ferric reductase, hydrogenase, and electron transport indicated that iron reduction by these bacteria is an enzymatic process. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Zhou, JZ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI phelps, tommy/A-5244-2011 NR 62 TC 73 Z9 85 U1 0 U2 13 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD DEC PY 2002 VL 68 IS 12 BP 6013 EP 6020 DI 10.1128/AEM.68.12.6013-6020.2002 PG 8 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 619WP UT WOS:000179500700027 PM 12450823 ER PT J AU Kingsley, MT Straub, TA Call, DR Daly, DS Wunschel, SC Chandler, DP AF Kingsley, MT Straub, TA Call, DR Daly, DS Wunschel, SC Chandler, DP TI Fingerprinting closely related Xanthomonas pathovars with random nonamer oligonucleotide microarrays SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID FRAGMENT-LENGTH-POLYMORPHISM; POLYMERASE-CHAIN-REACTION; 16S RIBOSOMAL-RNA; ORYZAE PV ORYZAE; DNA MICROARRAYS; HYBRIDIZATION; STRAINS; ARRAYS; PCR; SEQUENCES AB Current bacterial DNA-typing methods are typically based on gel-based fingerprinting methods. As such, they access a limited complement of genetic information and many independent restriction enzymes or probes are required to achieve statistical rigor and confidence in the resulting pattern of DNA fragments. Furthermore, statistical comparison of gel-based fingerprints is complex and nonstandardized. To overcome these limitations of gel-based microbial DNA fingerprinting, we developed a prototype, 47-probe microarray consisting of randomly selected nonamer oligonucleotides. Custom image analysis algorithms and statistical tools were developed to automatically extract fingerprint profiles from microarray images. The prototype array and new image analysis algorithms were used to analyze 14 closely related Xanthomonas pathovars. Of the 47 probes on the prototype array, 10 had diagnostic value (based on a chi-squared test) and were used to construct statistically robust microarray. fingerprints. Analysis of the microarray fingerprints showed clear differences between the 14 test organisms, including the separation of X. oryzae strains 43836 and 49072, which could not be resolved by traditional gel electrophoresis of REP-PCR amplification products. The proof-of-application study described here represents an important first step to high-resolution bacterial DNA fingerprinting with microarrays. The universal nature of the nonamer fingerprinting microarray and data analysis methods developed here also forms a basis for method standardization and application to the forensic identification of other closely related bacteria. C1 Pacific NW Natl Lab, Environm Characterizat & Risk Assessment Grp, Richland, WA 99352 USA. Pacific NW Natl Lab, Analyt Microbiol Grp, Richland, WA 99352 USA. Pacific NW Natl Lab, Appl Stat Grp, Richland, WA 99352 USA. Washington State Univ, Dept Vet Microbiol & Pathol, Pullman, WA 99164 USA. RP Chandler, DP (reprint author), Argonne Natl Lab, Biochip Technol Ctr, 9700 S Cass Ave,Bldg 202,A-249, Argonne, IL 60439 USA. EM dchandler@anl.gov NR 44 TC 26 Z9 28 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD DEC PY 2002 VL 68 IS 12 BP 6361 EP 6370 DI 10.1128/AEM.68.12.6361-6370.2002 PG 10 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 619WP UT WOS:000179500700065 PM 12450861 ER PT J AU Sae-Lao, B Soufli, R AF Sae-Lao, B Soufli, R TI Measurements of the refractive index of yttrium in the 50-1300-eV energy region SO APPLIED OPTICS LA English DT Article ID PHOTOABSORPTION; MOLYBDENUM AB The first experimental results to our knowledge on the refractive index (n) over tilde = 1 - delta + ibeta of yttrium in the extreme-ultraviolet and soft x-ray energy ranges are discussed. To determine the absorptive part beta, transmittance measurements were performed on pure yttrium. films in the 50-1300-eV energy region at beamline 6.3.2 of the Advanced Light Source. The dispersive part delta was then calculated from the absorption results by means of the Kramers-Kronig transformation. Compared with prior tabulated values, the new set of data for the refractive index of yttrium is in better agreement with the sum rules and contains previously unresolved fine structure information in the regions of the M-2,(3) and M-4,(5) absorption edges, where yttrium-based multilayer mirrors operate. (C) 2002 Optical Society of America. C1 Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Sae-Lao, B (reprint author), Univ Space Res Assoc, Natl Synchrotron Light Source Beamline X24C, Brookhaven Natl Lab, Upton, NY 11973 USA. EM benjawan@bnl.gov NR 19 TC 32 Z9 32 U1 1 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD DEC 1 PY 2002 VL 41 IS 34 BP 7309 EP 7316 DI 10.1364/AO.41.007309 PG 8 WC Optics SC Optics GA 620UT UT WOS:000179551400022 PM 12477123 ER PT J AU Ivill, M Patel, M Kim, K Bae, H Pearton, SJ Norton, DP Budai, JD AF Ivill, M Patel, M Kim, K Bae, H Pearton, SJ Norton, DP Budai, JD TI Epitaxial growth of CeO2 on (100) InP using reactive r.f. magnetron sputtering SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article ID PULSED-LASER DEPOSITION; FILMS; MGO; (100)INP; OXIDE AB The epitaxial growth of CeO2 thin films has been realized on (100) InP substrates using reactive r.f. magnetron sputtering. Oxide films were nucleated in the presence of molecular hydrogen (4% H-2/Ar sputtering gas) in order to reduce the native oxide formation on the InP surface, which interferes with CeO2 epitaxy. A metal cerium target was used as the cation source, with water vapor serving as the oxidizing species. Epitaxial films were sputter-deposited at a substrate temperature of 550 degreesC 10(-3) Torr, Crystallinity of the oxide film in a H2O vapor pressure of approximately 10(-3) was examined using theta-2theta X-ray diffraction, omega-rocking curves, and in-plane phi-scans. The best results were obtained when the initial nucleation layer was deposited with P(H2O) < 10(-5) Torr, followed by deposition at P(H2O) = 10(-3) Torr. The epitaxial growth of CeO2 on InP could prove enabling in efforts to integrate functional oxides with InP-based optoelectronic and microwave technologies. 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, Gainesville, FL 32611 USA. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 11 TC 3 Z9 3 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 75 IS 6 BP 699 EP 702 DI 10.1007/s003390201411 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 594UK UT WOS:000178069200012 ER PT J AU Abernathy, DL AF Abernathy, DL TI Optimizing Fermi-chopper spectrometers for the spallation neutron source SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The construction of the next-generation Spallation Neutron Source (SNS) at Oak Ridge National Laboratory offers an opportunity to optimize instrument performance in conjunction with moderator and target building configurations. For direct-geometry inelastic scattering instruments operating in the moderate-to high-energy range, the constraints on performance are often given by geometrical considerations. The implications for the specific case of the SNS are explored using simple analytical models of the performance of Fermi-chopper spectrometers. Two instrument configurations are proposed, based on user input concerning the desired instrument capabilities as well as current practices at existing spallation sources. C1 Oak Ridge Natl Lab, Spallat Neutron Source Project, Oak Ridge, TN 37831 USA. RP Abernathy, DL (reprint author), Argonne Natl Lab, IPNS SNS, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Abernathy, Douglas/A-3038-2012 OI Abernathy, Douglas/0000-0002-3533-003X NR 4 TC 3 Z9 3 U1 1 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1595 EP S1597 DI 10.1007/s003390101257 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600219 ER PT J AU Adachi, T Oku, T Morita, S Ohmori, H Takizawa, Y Shimizu, HM Suzuki, J Loong, CK Littrell, KC Goyette, R AF Adachi, T Oku, T Morita, S Ohmori, H Takizawa, Y Shimizu, HM Suzuki, J Loong, CK Littrell, KC Goyette, R TI Development of neutron compound refractive optics: a progress report SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID LENS AB We have designed and fabricated a compound refractive prism made of MgF2 single-crystal elements. The performance of this prism in refracting neutrons of wavelengths from 2 to 15 Angstrom was determined by time-of-flight transmission measurements. The total refractive angle was established as being 2.8 mrad for 10-Angstrom neutrons, and the transmission was 80%-98% for cold neutrons according to wavelength. C1 RIKEN, Wako, Saitama 3510198, Japan. Univ Tokyo, Bunkyo Ku, Tokyo 1138654, Japan. Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. RP Adachi, T (reprint author), RIKEN, 2-1 Hirosawa, Wako, Saitama 3510198, Japan. RI Ohmori , Hitoshi /A-7562-2015; Littrell, Kenneth/D-2106-2013 OI Littrell, Kenneth/0000-0003-2308-8618 NR 9 TC 6 Z9 6 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S180 EP S182 DI 10.1007/s003390201653 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600059 ER PT J AU Agamalian, M Iolin, E Kaiser, H Rehm, C Werner, SA AF Agamalian, M Iolin, E Kaiser, H Rehm, C Werner, SA TI A new dynamical diffraction-based technique of residual stress measurements in thin films SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The recently discovered dynamical diffraction effect 'neutron camel' was used for residual stress measurements in a thick Si (111) crystal coated with a 2000 A-thick Ni film. The observed asymmetry of the back-face rocking curve corresponds to the bending radius of similar to 19 km and the tension force applied to the Ni film is similar to 90 N/m. Relative deformation of the Si crystallographic cells in the vicinity of diffractive surfaces is \partial derivativeu(z)/partial derivative(z)\ approximate to 1.6 x 10(-6). C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Missouri, Columbia, MO 65211 USA. NIST, Gaithersburg, MD 20899 USA. RP Agamalian, M (reprint author), Argonne Natl Lab, IPNS, 9700 S Cass Ave,Bldg 360, Argonne, IL 60439 USA. OI Agamalian, Michael/0000-0002-9112-2534 NR 9 TC 2 Z9 2 U1 1 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1686 EP S1688 DI 10.1007/s003390101263 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600248 ER PT J AU Ankner, JF Jansma, M Blakeman, ED Kellogg, RL AF Ankner, JF Jansma, M Blakeman, ED Kellogg, RL TI The optical design of the SNS liquids reflectometer SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB We present the optical design of the liquids reflectometer currently under construction at the Spallation Neutron Source. By utilizing a multi-channel bender and a tapered guide, we can eliminate sample-moderator line-of-sight and provide angular dispersion for reflectivity measurements of liquid surfaces. The fast-neutron background of such an instrument is comparable to that present in a direct-view instrument employing a 30-cm thick Inconel t(0) chopper. C1 Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN USA. RP Ankner, JF (reprint author), Argonne Natl Lab, 9700 S Cass Ave,IPNS Bldg 360, Argonne, IL 60439 USA. OI Ankner, John/0000-0002-6737-5718 NR 7 TC 1 Z9 1 U1 2 U2 10 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1610 EP S1612 DI 10.1007/s003390101258 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600224 ER PT J AU Bao, W Trevino, SF Lynn, JW Pagliuso, PG Sarrao, JL Thompson, JD Fisk, Z AF Bao, W Trevino, SF Lynn, JW Pagliuso, PG Sarrao, JL Thompson, JD Fisk, Z TI Effect of pressure on magnetic structure in heavy-fermion CeRhIn5 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID UNCONVENTIONAL SUPERCONDUCTIVITY; CEIRIN5; CECOIN5 AB The effect of hydrostatic pressure on the incommensurate antiferromagnetic structure of CeRhIn5 is investigated with neutron diffraction using a He pressure cell. At 3.8 kbar, the staggered magnetic moment is 0.37(4) mu(B) per Ce ion at 1.6 K, which is the same as the ambient-pressure value. The Neel temperature T-N = 3.8(l) K is also the same as the ambient-pressure one, although the curve of the order parameter has changed with pressure. The incommensurability delta of the magnetic wave vector q(M) = (1/2, 1/2, delta) has reduced from delta = 0.297 at ambient pressure to delta = 0.294(l) at 3.8 kbar. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. USA, Res Lab, Adelphi, MD 20783 USA. Florida State Univ, Tallahassee, FL 32306 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. EM wbao@lanl.gov RI Pagliuso, Pascoal/C-9169-2012; Bao, Wei/E-9988-2011 OI Bao, Wei/0000-0002-2105-461X NR 22 TC 2 Z9 2 U1 0 U2 5 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0947-8396 EI 1432-0630 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S557 EP S558 DI 10.1007/s003390101121 PN 1 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600186 ER PT J AU Benmore, CJ Tomberli, B Neuefeind, J Egelstaff, PA AF Benmore, CJ Tomberli, B Neuefeind, J Egelstaff, PA TI Isotopic quantum correction to liquid methanol at-30 degrees C SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID ENERGY PHOTON DIFFRACTION; WATER AB Hydrogen/deuterium (H/D) substitution of molecular liquids in neutron diffraction is a powerful tool for structure determination. However, recent high-energy X-ray studies have found observable differences in the structures of many H and D liquids at the same temperature. In some cases this isotopic quantum effect can be corrected for by measuring the D sample at a slightly different temperature to the H sample. The example of hydroxyl isotopic substitution in liquid methanol at -30degreesC is presented. The magnitude of the quantum effect is shown to be significant when compared to the size of the first-order isotopic neutron-difference function. C1 Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Univ Guelph, Dept Phys, Guelph, ON N1G 2W1, Canada. DESY, Hamburger Synchrontronstschlungslab HASYLAB, D-22603 Hamburg, Germany. RP Benmore, CJ (reprint author), Argonne Natl Lab, Div Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Neuefeind, Joerg/D-9990-2015; OI Neuefeind, Joerg/0000-0002-0563-1544; Benmore, Chris/0000-0001-7007-7749 NR 8 TC 1 Z9 1 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1670 EP S1672 DI 10.1007/s003390201769 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600243 ER PT J AU Boni, P Clementyev, E Stadler, C Roessli, B Shirane, G Werner, SA AF Boni, P Clementyev, E Stadler, C Roessli, B Shirane, G Werner, SA TI Fincher-Burke excitations in single-Q chromium SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID MAGNETIC EXCITATIONS; SPIN AB The low-energy excitations of incommensurate antiferromagnetic Cr have been investigated by means of high-resolution, inelastic neutron scattering with unpolarized, cold neutrons within an energy range E < 9 meV. In agreement with previous measurements we observe Fincher-Burke excitations in the transverse spin density wave phase that appear between the unresolved spin-wave peaks at the incommensurate positions Q(+/-) = (1 +/- delta, 0, 0). In contrast to the previous measurements, our high-resolution data shows that the Fincher-Burke modes do not follow a linear dispersion. Therefore, they have nothing in common with the acoustic phonon branch. The major part of the scattering is concentrated in the range 4 meV < E < 8 meV. C1 NIST, Gaithersburg, MD 20899 USA. Tech Univ Munich, Phys Dept E21, D-85747 Garching, Germany. ETHZ, Neutron Scattering Lab, CH-5232 Villigen, PSI, Switzerland. PSI, CH-5232 Villigen, PSI, Switzerland. Brookhaven Natl Lab, Dept Phys, Upton, NY 11974 USA. RP Werner, SA (reprint author), NIST, Mail Stop 8461, Gaithersburg, MD 20899 USA. NR 7 TC 3 Z9 3 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S716 EP S718 DI 10.1007/s003390201625 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600239 ER PT J AU Bordallo, HN Chapon, LC Cook, JC Copley, JRD Goremychkin, E Kern, S Lee, SH Yildirim, T Manson, JL AF Bordallo, HN Chapon, LC Cook, JC Copley, JRD Goremychkin, E Kern, S Lee, SH Yildirim, T Manson, JL TI Spin excitations in 3D molecular magnets probed by neutron scattering SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The emerging field of molecular magnetism constitutes a new branch of materials science that deals with the magnetic properties of molecules, or assemblies of molecules, that contain magnetic centers. The growing interest in understanding the origin of the magnetic ordering in these materials is to obtain novel multiproperty molecular magnetic materials with high transition temperatures. Molecules based on the dicyanamide ion [N equivalent to C-N-Cequivalent toN], abbreviated (dca), such as M(dca)(2) [M = Mn, Ni], have shown interesting bulk properties that prompted our inelastic neutron scattering (INS) studies. While the Mn2+ ion is isotropic because of its L = 0 configuration, the isostructural Ni analog has S = I and demonstrates marked single-ion anisotropy. Mn(dca)(2) is a canted antiferromagnet below 16 K, while Ni(dca)(2) is a ferromagnet below 21 K. INS has been used to investigate the magnetic excitations in Mn(dca)(2) and Ni(dca)(2). For Mn(dca)(2), a Heisenberg model gives good correspondence with the experimental results. C1 Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. NIST, Ctr Neurton Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. Colorado State Univ, Dept Phys, Ft Collins, CO 80523 USA. RP Bordallo, HN (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI yildirim, taner/A-1290-2009; Bordallo, Heloisa/I-6836-2012 OI Bordallo, Heloisa/0000-0003-0750-0553 NR 14 TC 6 Z9 6 U1 0 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S634 EP S636 DI 10.1007/s003390201350 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600212 ER PT J AU Bourke, MAM Dunand, DC Ustundag, E AF Bourke, MAM Dunand, DC Ustundag, E TI SMARTS - a spectrometer for strain measurement in engineering materials SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB A new spectrometer called SMARTS (Spectrometer for Materials Research at Temperature and Stress) has been commissioned at the Los Alamos neutron science center and entered the user program in August of 2002. Its design maximizes capability and throughput for measurements of (a) residual macrostrain in engineering components and (b) in situ loading. This paper describes some aspects of the instrument. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. CALTECH, Dept Mat Sci, Pasadena, CA 91125 USA. RP Bourke, MAM (reprint author), Los Alamos Natl Lab, MS H805, Los Alamos, NM 87545 USA. RI Dunand, David/B-7515-2009; Ustundag, Ersan/C-1258-2009; OI Ustundag, Ersan/0000-0002-0812-7028; Dunand, David/0000-0001-5476-7379 NR 3 TC 103 Z9 104 U1 0 U2 12 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1707 EP S1709 DI 10.1007/s003390201747 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600255 ER PT J AU Chatterjee, A Mikkelson, D Mikkelson, R Hammonds, J Worlton, T AF Chatterjee, A Mikkelson, D Mikkelson, R Hammonds, J Worlton, T TI Remote access and display of neutron data SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB With the proliferation of high-intensity neutron sources and involvement of scientists from diverse areas, it is important to provide methods for remote access and display of data. We have developed an integrated spectral analysis workbench (ISAW) that can read, merge or combine, operate on, and visualize large arrays of data. ISAW is written in Java to allow it to run on common user workstations and to facilitate network communications. Recently, we added the ability to remotely access live data made available through a data server running on the control computer. This data server receives UDP data packets from a data sender running as part of the data-acquisition system and sends TCP data packets requested by ISAW clients running on user desktop systems. C1 Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Univ Wisconsin, Dept Math & Comp Sci, Menomonie, WI 54751 USA. RP Chatterjee, A (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 3 TC 8 Z9 8 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S194 EP S197 DI 10.1007/s003390201654 PN 1 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600064 ER PT J AU Coldea, R Tennant, DA Habicht, K Smeibidl, P Tylczynski, Z AF Coldea, R Tennant, DA Habicht, K Smeibidl, P Tylczynski, Z TI Full ferromagnetic saturation of a two-dimensional quantum antiferromagnet SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID QUASI-1D S=1/2 ANTIFERROMAGNET; CS2CUCL4 AB Cs2CuCl4 is a 2D frustrated quantum magnet that has recently been shown to display a very unusual quantum spin liquid state. The excitations are not spin-1 magnons as observed in other un-frustrated 2D quantum magnets but instead are spinons carrying a fractional spin of 1/2, as predicted by a resonating-valence-bond picture. Here we use high magnetic fields to induce a transition from this fractional quantum spin-liquid phase to the fully-polarized phase where spins are ferromagnetically aligned along the field. In this field-induced phase all quantum fluctuations are quenched by the external field and the system is expected to behave like a classical magnet with spin-1 magnon excitations. Measurements are made in fields up to 12T and temperatures below 0.2 K. Ferromagnetic saturation is observed at the critical field B-c = 8.44(1) T parallel to a. Above B-c the measured excitations lineshapes show well-defined, almost resolution-limited peaks as expected for spin-1 magnons and are gapped throughout the zone. The gap to the lowest energy excitation decreases linearly upon decreasing field and closes at B-c, below which the system orders into a cone phase. This transition provides an opportunity to study how ordered phases arise from the condensation of excitations. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. Clarendon Lab, Oxford OX1 3PU, England. BENSC, Hahn Meitner Inst, D-14109 Berlin, Germany. Tech Univ Darmstadt, Inst Festkorperphys, D-64289 Darmstadt, Germany. Adam Mickiewicz Univ Poznan, Inst Phys, PL-61614 Poznan, Poland. RP Coldea, R (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Tennant, David/Q-2497-2015; Habicht, Klaus/K-3636-2013 OI Tennant, David/0000-0002-9575-3368; Habicht, Klaus/0000-0002-9915-7221 NR 7 TC 0 Z9 0 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S904 EP S906 DI 10.1007/s003390101163 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600302 ER PT J AU Edwards, H Lefmann, K Lake, B Nielsen, K Skaarup, P AF Edwards, H Lefmann, K Lake, B Nielsen, K Skaarup, P TI Simulation of a complete inelastic neutron scattering experiment SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID SUPERCONDUCTOR AB A simulation of an inelastic neutron scattering experiment on the high-temperature superconductor La2-xSrxCuO4 is presented. The complete experiment, including sample, is simulated using an interface between the experiment control program and the simulation software package (McStas) and is compared with the experimental data. Simulating the entire experiment is an attractive alternative to the usual method of convoluting the model cross section with the resolution function, especially if the resolution function is nontrivial. C1 Riso Natl Lab, Mat Res Dept, DK-4000 Roskilde, Denmark. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lefmann, K (reprint author), Riso Natl Lab, Mat Res Dept, DK-4000 Roskilde, Denmark. RI Lefmann, Kim/M-9228-2014; OI Lefmann, Kim/0000-0003-4282-756X; Lake, Bella/0000-0003-0034-0964 NR 7 TC 3 Z9 3 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1492 EP S1494 DI 10.1007/s003390201904 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600186 ER PT J AU Egami, T McQueeney, RJ Chung, JH Yethiraj, M Mook, HA Arai, M Inamura, Y Endoh, Y Tajima, S Frost, C Dogan, F AF Egami, T McQueeney, RJ Chung, JH Yethiraj, M Mook, HA Arai, M Inamura, Y Endoh, Y Tajima, S Frost, C Dogan, F TI Lattice and charge effects in high-temperature superconductors SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID OXIDE SUPERCONDUCTORS; YBA2CU3O7; CRYSTAL; PHONONS AB We present the results of inelastic neutron-scattering measurements of a twinned crystal of YBa2Cu3O6.95 using the MAPS spectrometer of the ISIS facility of the Rutherford-Appleton Laboratory as well as the HFIR of the Oak Ridge National Laboratory. The dispersion of the Cu-O bond-stretching modes indicates a strong dielectric anisotropy within the plane and associated electronic anisotropy, supporting the dynamic stripe model. The results suggest a possibility that phonons play a major role in the mechanism of high-temperature superconductivity. C1 Univ Penn, Res Struct Matter Lab, Philadelphia, PA 19104 USA. Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. KEK, Inst Mat Struct Sci, Tsukuba, Ibaraki 3050801, Japan. Tohoku Univ, Inst Mat Res, Sendai, Miyagi 980, Japan. Int Superconduct Technol Ctr, Superconduct Res Lab, Tokyo 1350062, Japan. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Washington, Dept Mat Sci, Seattle, WA 98195 USA. RP Univ Penn, Res Struct Matter Lab, Philadelphia, PA 19104 USA. EM egami@seas.upenn.edu RI McQueeney, Robert/A-2864-2016 OI McQueeney, Robert/0000-0003-0718-5602 NR 19 TC 0 Z9 0 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0947-8396 EI 1432-0630 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1635 EP S1637 DI 10.1007/s003390201933 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600232 ER PT J AU Fischer, HE Cuello, GJ Palleau, P Feltin, D Barnes, AC Badyal, YS Simonson, JM AF Fischer, HE Cuello, GJ Palleau, P Feltin, D Barnes, AC Badyal, YS Simonson, JM TI D4c: A very high precision diffractometer for disordered materials SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The disordered-materials diffractometer D4 at the Institut Laue-Langevin (ILL) has been thoroughly upgraded through improvements in detectors, collimation and shielding to become the D4c instrument. A larger solid angle of detection has increased the total counting rate by a factor of 5, thereby reducing random error in the diffraction measurement, and a corresponding factor of 5 improvement in detector stability has reduced the principal cause of systematic error. The overall precision of the instrument has therefore been increased by a factor of 5 as compared to its previous version, D4b. We present an overview of the D4c instrument's design as well as some results of the successful very high precision experiments performed at D4c since its commissioning in May/June 2000. C1 Ctr Univ Paris Sud, Lab LURE, F-91898 Orsay, France. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Fischer, HE (reprint author), Ctr Univ Paris Sud, Lab LURE, Bat 209D,BP 34, F-91898 Orsay, France. RI Cuello, Gabriel/C-5831-2009; Fischer, Henry/D-5299-2012 OI Cuello, Gabriel/0000-0003-3844-0602; Fischer, Henry/0000-0002-1204-0750 NR 6 TC 112 Z9 112 U1 0 U2 10 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S160 EP S162 DI 10.1007/s003390101087 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600052 ER PT J AU Frontera, C Garcia-Munoz, JL Aranda, MAG Ritter, C Llobet, A Ranno, L Respaud, M Vanacken, J Broto, JM Carrillo, AE Calleja, A Garcia, J AF Frontera, C Garcia-Munoz, JL Aranda, MAG Ritter, C Llobet, A Ranno, L Respaud, M Vanacken, J Broto, JM Carrillo, AE Calleja, A Garcia, J TI Anomalously high charge/orbital ordering temperature in Bi0.5Sr0.5MnO3 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID CHARGE; MN AB Neutron/synchrotron diffraction data and magnetic measurements provide direct evidence of charge/orbital ordering at anomalously high temperatures in Bi0.5Sr0.5MnO3, as well as in other (Bi, Sr)MnO3 manganites. We report on the electronic and magnetic transitions of these oxides. The origin of the high value of the charge/orbital ordering temperature is discussed. C1 CSIC, ICMAB, Bellaterra 08193, Spain. Univ Malaga, Dept Quim Inorgan Cristalog & Mineral, E-29071 Malaga, Spain. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. CNRS, Lab Louis Neel, F-38042 Grenoble 9, France. Inst Natl Sci Appl, SNCMP, F-31077 Toulouse, France. Inst Natl Sci Appl, LPMC, F-31077 Toulouse, France. Katholieke Univ Leuven, LVSM, B-3001 Louvain, Belgium. Univ Barcelona, Fac Quim, Dept Engn Quim & Met, E-08028 Barcelona, Spain. RP Frontera, C (reprint author), CSIC, ICMAB, Campus Bellaterra, Bellaterra 08193, Spain. RI Calleja, Alberto/B-2248-2008; Aranda, Miguel A.G./D-4614-2009; Frontera, Carlos/B-4910-2008; Llobet, Anna/B-1672-2010; D2B, Instrument/F-1072-2012; Lujan Center, LANL/G-4896-2012; Vanacken, Johan/F-3026-2013; Garcia-Munoz, Jose Luis /A-7983-2015; OI Aranda, Miguel A.G./0000-0001-7708-3578; Frontera, Carlos/0000-0002-0091-4756; Garcia-Munoz, Jose Luis /0000-0002-4174-2794; Ranno, Laurent/0000-0002-1901-2285 NR 8 TC 2 Z9 2 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1787 EP S1789 DI 10.1007/s003390201765 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600281 ER PT J AU Gilbert, EP AF Gilbert, EP TI Modulated structure formation in demixing paraffin blends SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID MICROPHASE SEPARATION; PHASE-SEPARATION; SOLID-SOLUTIONS; ALKANES AB Small angle scattering (SANS and SAXS) and differential scanning calorimetry have been measured from C-28 : C-36 normal paraffin mixtures of varying composition quenched from the melt. Satellite peaks are observed in the SAXS whose offset in Q, relative to Bragg diffraction peaks associated with the average structure, are composition dependent. The offset is close to the position of the most intense peak observed in SANS. Scattering from the quenched structures is consistent with a correlated displacement and substitutional disorder model yielding modulations that are incommensurate with the average lattice. DSC shows an additional endotherm in the mixtures that is not present in the pure components and is associated with this superstructure formation. C1 Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Gilbert, EP (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Gilbert, Elliot/A-5566-2010 OI Gilbert, Elliot/0000-0001-6413-7813 NR 13 TC 0 Z9 0 U1 0 U2 6 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S339 EP S341 DI 10.1007/s003390201348 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600112 ER PT J AU Glagolenko, IY Carney, KP Kern, S Goremychkin, EA Udovic, TJ Copley, JRD Cook, JC AF Glagolenko, IY Carney, KP Kern, S Goremychkin, EA Udovic, TJ Copley, JRD Cook, JC TI Quantitative analysis of UH3 in U metal and UO2 matrices by neutron vibrational spectroscopy SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The ignition of UH3 has resulted in uranium fires. Neutron spectroscopy is proposed to quantify UH3 in fuel at risk. Spectra of UH3 in UO2 and U metal were obtained using two instruments at Argonne National Laboratory and two instruments at the National Institute of Standards and Technology. Analytical standards were prepared with powders of UH3, UO2 and U metal. Linear relationships were found between the mass of UH3 and the integrated intensity of the inelastic scattering associated with hydrogen motions. We discuss the relative merits of the different spectrometers for this type of measurement. C1 Argonne Natl Lab W, Idaho Falls, ID 83403 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Glagolenko, IY (reprint author), Argonne Natl Lab W, POB 2528, Idaho Falls, ID 83403 USA. NR 6 TC 2 Z9 2 U1 1 U2 13 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1397 EP S1399 DI 10.1007/s003390201808 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600155 ER PT J AU Goel, P Rao, MN Choudhury, N Chaplot, SL Ghose, S Yethiraj, M AF Goel, P Rao, MN Choudhury, N Chaplot, SL Ghose, S Yethiraj, M TI Phonon-dispersion relations in andalusite and sillimanite, A1(2)SiO(5) SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID INELASTIC NEUTRON-SCATTERING; LATTICE-DYNAMICS; HEAT-CAPACITIES; PHASE-DIAGRAM; AL2SIO5; ENTROPIES; KYANITE AB This paper reports single-crystal inelastic neutron scattering measurements of the phonon-dispersion relations of the aluminium silicate minerals andalusite and sillimanite, Al2SiO5. The measurements were undertaken using the triple-axis spectrometer at the Dhruva reactor, Trombay for andalusite and at the Oak Ridge National Laboratory, USA for sillimanite. The phonon-dispersion relations (up to 50 meV) along various high-symmetry directions have been measured and have been analyzed on the basis of lattice dynamics shell model calculations. The calculated structure factors based on the model calculations were used as guides for planning these single-crystal measurements and have been used to identify regions in reciprocal space with large cross sections. The calculated phonon-dispersion relations are in good agreement with the measured data. The model has been successfully used to derive the high pressure-temperature thermodynamic properties like the specific heat and the equation of state. C1 Bhabha Atom Res Ctr, Div Solid State Phys, Bombay 400085, Maharashtra, India. Univ Washington, Dept Earth & Space Sci, Mineral Phys Grp, Seattle, WA 98195 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Rao, MN (reprint author), Bhabha Atom Res Ctr, Div Solid State Phys, Bombay 400085, Maharashtra, India. NR 13 TC 2 Z9 2 U1 1 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1149 EP S1151 DI 10.1007/s003390201683 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600072 ER PT J AU Granroth, GE Nagler, SE Coldea, R Eccleston, RS Ward, BH Talham, DR Meisel, MW AF Granroth, GE Nagler, SE Coldea, R Eccleston, RS Ward, BH Talham, DR Meisel, MW TI Neutron-scattering studies of the S = 2 antiferromagnetic chain MnCl3(C10D8N2) SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID HALDANE-GAP; HEISENBERG; DYNAMICS AB Quasi-elastic and inelastic neutron scattering studies of the quasi-one-dimensional S = 2 antiferromagnet MnCl3(C10D8N2) are reported. The quasi-elastic measurements exhibit a broad peak at Q approximate to 0.69 Angstrom(-1), which is consistent with short-range antiferromagnetic coupling between neighboring Mn3+ ions. Inelastic experiments, at 150 mK and Q = 0.70 Angstrom(-1), reveal decreased magnetic scattering at energies less than 0.2 meV when compared to similar studies at 20 K. These results provide microscopic evidence for the presence of a Haldane gap and are consistent with the bulk magnetization measurements of Granroth et al. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Rutherford Appleton Lab, ISIS Facil, Chilton OX11 0QX, England. Univ Florida, Dept Chem, Gainesville, FL 32611 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. RP Granroth, GE (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Nagler, Stephen/B-9403-2010; Nagler, Stephen/E-4908-2010; Granroth, Garrett/G-3576-2012 OI Nagler, Stephen/0000-0002-7234-2339; Granroth, Garrett/0000-0002-7583-8778 NR 13 TC 4 Z9 4 U1 0 U2 8 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S868 EP S870 DI 10.1007/s003390101160 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600290 ER PT J AU Hakem, IF Lal, J AF Hakem, IF Lal, J TI Evidence of solvent-dependent complexation in non-ionic polymer-salt systems SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB Small angle neutron scattering measurements have been performed on polyethylene oxide (PEO)-salt solutions. An attempt is made to characterize experimentally the scattering behavior of aqueous (D2O) polyethylene oxide and PEO-methanol solutions in the presence of potassium iodide (KI). In water solution, no interactions were observed with KI and PEO. However, in methanol a definite indication of complex formation was found. Addition of KI to a solution of PEO in methanol shows a large change in interchain interaction and chain conformation. C1 Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. Tlemcen Univ, Fac Sci, Dept Phys, Tilimsen 13000, Algeria. RP Lal, J (reprint author), Argonne Natl Lab, IPNS, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Hakem, Ilhem F. /C-8374-2014 NR 6 TC 2 Z9 2 U1 3 U2 10 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S531 EP S533 DI 10.1007/s003390201873 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600177 ER PT J AU Herwig, KW Keener, WS AF Herwig, KW Keener, WS TI Design and performance of the spallation neutron source backscattering spectrometer SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB When the Spallation Neutron Source is operational in 2006 at Oak Ridge National Laboratory, it will provide the most intense pulsed neutron beams in the world for research. This paper describes the expected performance of the near-backscattering, crystal-analyzer spectrometer designed to provide extremely high energy resolution at the elastic peak (deltaomega = 2.2-2.7 mueV, varying with sample dimension). The design requires a long initial guide section of 84 m from moderator to sample in order to achieve the requisite timing resolution. This spectrometer will provide an unprecedented dynamic range near the elastic peak of -258 mueV < omega < 258 mueV. For experiments that require the full dynamic range available at comparable reactor-based instruments (or greater), this spectrometer is expected to have an effective count rate similar to 60 times that of the current best spectrometers. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Herwig, KW (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Herwig, Kenneth/F-4787-2011 NR 4 TC 10 Z9 10 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1592 EP S1594 DI 10.1007/s003390101256 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600218 ER PT J AU Hosokawa, S Sinn, H Hensel, F Alatas, A Alp, EE Pilgrim, WC AF Hosokawa, S Sinn, H Hensel, F Alatas, A Alp, EE Pilgrim, WC TI Short-wavelength collective excitations in liquid mercury investigated by inelastic X-ray scattering SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID DYNAMIC STRUCTURE FACTOR; NEUTRON-SCATTERING; MONATOMIC LIQUIDS; RESOLUTION; LITHIUM; SOUND; WATER AB Short-wavelength collective excitations in liquid mercury at room temperature have been studied by inelastic X-ray scattering. Up to Q values of about 17 nm(-1), clear evidence for the existence of propagating modes was found from the shape of S(Q, omega) at constant Q. The Q-omega behaviour of these excitations is described in a simplified viscoelastic view. C1 Univ Marburg, Inst Phys Nucl & Macromol Chem, D-35032 Marburg, Germany. Argonne Natl Lab, SRI CAT, Adv Photon Source, Argonne, IL 60439 USA. RP Hosokawa, S (reprint author), Univ Marburg, Inst Phys Nucl & Macromol Chem, D-35032 Marburg, Germany. NR 24 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1648 EP S1650 DI 10.1007/s003390201800 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600236 ER PT J AU Hussey, D Fan, S Neff, B Bailey, C Snow, WM Rich, D Thompson, AK Gentile, TR Velthuis, SGET Felcher, GP AF Hussey, D Fan, S Neff, B Bailey, C Snow, WM Rich, D Thompson, AK Gentile, TR Velthuis, SGET Felcher, GP TI Simultaneous polarization analysis of Zeeman splitting in polarized neutron reflectometry using a polarized He-3 neutron-spin filter SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID REFLECTIVITY AB A polarized He-3 neutron-spin filter was used to analyze polarized neutrons reflected from a 1000-Angstrom-thick Fe film immersed in a magnetic field. The spin filter analyzed both the specularly reflected component and the off-specular component caused by the phenomenon of Zeeman splitting of surface-scattered neutrons observed by Felcher et al. and investigated in more detail in subsequent experiments. The sample of polarized He-3 was polarized by metastability-exchange optical pumping and compressed into a glass cell at the Indiana University Cyclotron Facility. The polarized gas was transported by car in a battery-powered solenoid holding field to the neutron reflectometry instrument POSY I at the Intense Pulsed Neutron Source at Argonne National Laboratory. Using the large solid angle of the polarized He-3 spin filter, we were able to simultaneously analyze both components to the scattering and verify (as expected) that the polarization of the specular component was unchanged upon reflection and that the polarization of the off-specular component was reversed. To our knowledge this work represents the second experiment to employ a polarized He-3 neutron-spin filter in polarized neutron reflectometry. C1 Indiana Univ, Cyclotron Facil, Bloomington, IN 47404 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Hussey, D (reprint author), Indiana Univ, Cyclotron Facil, 2401 Sampson Ln, Bloomington, IN 47404 USA. RI te Velthuis, Suzanne/I-6735-2013 OI te Velthuis, Suzanne/0000-0002-1023-8384 NR 12 TC 7 Z9 7 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S234 EP S236 DI 10.1007/s003390201396 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600078 ER PT J AU Kennedy, BJ Howard, CJ Prodjosantoso, AK Chakoumakos, BC AF Kennedy, BJ Howard, CJ Prodjosantoso, AK Chakoumakos, BC TI Neutron powder diffraction study of the rhombohedral to cubic phase transition in the series La1-xPrxAlO3 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID PEROVSKITE AB Neutron powder diffraction has been used to examine the structural changes of the rare-earth aluminates La1-xPrxAlO3 over a wide range of temperatures. At room temperature the aluminates adopt the rhombohedral perovskite structure in space group R (3) over barc. In all cases heating the sample results in a transition to cubic, the transition temperature increasing linearly with Pr content. The rhombohedral structure is characterised by rotation of the oxygen atom octahedra about the threefold axis. The maximum rotation angle also increases linearly with Pr content. C1 Univ Sydney, Sch Chem, Ctr Heavy Met Res, Sydney, NSW 2006, Australia. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Kennedy, BJ (reprint author), Univ Sydney, Sch Chem, Ctr Heavy Met Res, Sydney, NSW 2006, Australia. RI Howard, Christopher/B-5138-2009; Chakoumakos, Bryan/A-5601-2016; OI Chakoumakos, Bryan/0000-0002-7870-6543; Kennedy, Brendan/0000-0002-7187-4579; prodjosantso, anti/0000-0001-7603-5857 NR 12 TC 11 Z9 11 U1 1 U2 6 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1660 EP S1663 DI 10.1007/s003390201383 PN 2 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600240 ER PT J AU Kenzelmann, M Coldea, R Tennant, DA Visser, D Hofmann, M Smeibidl, P Tylczynski, Z AF Kenzelmann, M Coldea, R Tennant, DA Visser, D Hofmann, M Smeibidl, P Tylczynski, Z TI Field dependence of magnetic ordering in the frustrated XY magnet Cs2CoCl4 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID MODEL AB Low-dimensional magnets with low-spin quantum number are ideal model systems for investigating strongly interacting macroscopic quantum ground states and their nonlinear spin excitations. We present single-crystal neutrondiffraction measurements of the ordered phase of the quasione-dimensional spin-1/2 XY antiferromagnet CS2CoCl4 both in zero field and in fields up to 6.5 T. In zero field the system shows long-range order below T-N = 217 mK with a commensurate ordering wave-vector (0, 0.5, 0.5). With increasing magnetic field - applied perpendicular to the magnetic chain axis - the magnetic Bragg peak intensities increase monotonically, reaching a maximum at H = 1.4 T; evidence that the magnetic field suppresses quantum fluctuations in the ground state. At H-c = 2.1 T the ordered structure collapses in an apparent first-order phase transition, with no magnetic Bragg peaks being observed in the (0, k, l) scattering plane above this field. This result suggests that the magnetic field induces a phase transition to a spin-liquid ground state. Magnetic Bragg peak intensities at ferromagnetic positions increase quadratically up to about 2.8 T, corresponding to a linear increase of the magnetic moment. At higher magnetic fields, the intensity increases linearly up to 6.5 T. C1 Clarendon Lab, Oxford OX1 3PU, England. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. BENSC, Hahn Meitner Inst, D-14109 Berlin, Germany. Adam Mickiewicz Univ Poznan, Inst Phys, PL-61614 Poznan, Poland. RP Kenzelmann, M (reprint author), Clarendon Lab, Parks Rd, Oxford OX1 3PU, England. RI Kenzelmann, Michel/A-8438-2008; Tennant, David/Q-2497-2015 OI Kenzelmann, Michel/0000-0001-7913-4826; Tennant, David/0000-0002-9575-3368 NR 8 TC 0 Z9 0 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S901 EP S903 DI 10.1007/s0033990201369 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600301 ER PT J AU Klose, F Lee, WT AF Klose, F Lee, WT TI Optimization of the SNS magnetism reflectometer neutron-guide optics using Monte Carlo simulations SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The magnetism reflectometer at the spallation neutron source SNS will employ advanced neutron optics to achieve high data rate, improved resolution, and extended dynamic range. Optical components utilized will include a multi-channel polygonal curved bender and a tapered neutron-focusing guide section. The results of a neutron beam interacting with these devices are rather complex. Additional complexity arises due to the spectral/time-emission profile of the moderator and non-perfect neutron optical coatings. While analytic formulae for the individual components provide some design guidelines, a realistic performance assessment of the whole instrument can only be achieved by advanced simulation methods. In this contribution, we present guide optics optimizations for the magnetism reflectometer using Monte Carlo simulations. We compare different instrument configurations and calculate the resulting data rates. C1 Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37831 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Klose, F (reprint author), Oak Ridge Natl Lab, Spallat Neutron Source, POB 2008, Oak Ridge, TN 37831 USA. NR 2 TC 2 Z9 3 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1486 EP S1488 DI 10.1007/s003390201798 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600184 ER PT J AU Lazukov, VN Nefeodova, EV Sikolenko, VV Staub, U Alekseev, PA Braden, M Nemkovski, KS Pradervand, C Sadikov, IP Soderholm, L Tiden, NN AF Lazukov, VN Nefeodova, EV Sikolenko, VV Staub, U Alekseev, PA Braden, M Nemkovski, KS Pradervand, C Sadikov, IP Soderholm, L Tiden, NN TI Lattice anomalies in CeNi unstable valence compound SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB Neutron diffraction and X-ray absorption measurements have been performed to study the changes in the structure and the Ce valence between 10 K and 295 K. No evidence for a phase transition was obtained, but some nearest-neighbour distances have clear peculiarities in the temperature range of 100 K to 150 K. The valence of Ce increases continuously with decreasing temperature, which can explain neither the lattice anomalies nor the previously observed temperature dependence of the phonon frequencies. A correlation between the gap-like magnetic excitation spectrum formed at low temperatures and observed lattice anomalies is discussed. C1 Joint Inst Nucl Res, Dubna 141980, Moscow Region, Russia. Paul Scherrer Inst, SLS, CH-5232 Villigen, Switzerland. CEA Saclay, LLB, F-91191 Gif Sur Yvette, France. INFP, D-76021 Karlsruhe, Germany. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Lazukov, VN (reprint author), RRC Kurchatov Inst, Moscow 123182, Russia. RI Pradervand, Claude/I-8114-2013; Alekseev, Pavel/A-5645-2014; Sikolenko, Vadim/D-3869-2011; Staub, Urs/C-4914-2015; OI Sikolenko, Vadim/0000-0001-5252-6870; Nemkovski, Kirill/0000-0001-7752-4927 NR 7 TC 5 Z9 5 U1 0 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S559 EP S561 DI 10.1007/s003390201528 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600187 ER PT J AU Lee, WT Wang, XL Robertson, JL Klose, F Rehm, C AF Lee, WT Wang, XL Robertson, JL Klose, F Rehm, C TI IDEAS - a Monte Carlo simulation package for neutron-scattering instrumentation SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB Monte Carlo (MC) simulations are widely used in the design of neutron-scattering instruments. Several simulation packages have been developed in the past few years. We present here an analysis of the use of MC simulation techniques in neutron-scattering instrumentation. We also present IDEAS, an easy-to-use and easy-to-expand MC simulation package that has proven to be a versatile tool for the design of neutron-scattering instruments. C1 Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37831 USA. RP Lee, WT (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Wang, Xun-Li/C-9636-2010 OI Wang, Xun-Li/0000-0003-4060-8777 NR 5 TC 12 Z9 12 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1502 EP S1504 DI 10.1007/s003390201723 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600189 ER PT J AU Littrell, KC Thiyagarajan, P Carpenter, JM Seeger, PA AF Littrell, KC Thiyagarajan, P Carpenter, JM Seeger, PA TI Design of a TOF-SANS instrument for the proposed long-wavelength target station at the spallation neutron source SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID SCATTERING AB We have designed a versatile high-data-rate SANS instrument (broad-range intense multipurpose SANS (BRIMS)) for the proposed long-wavelength target station at the SNS using the Los Alamos NISP Monte Carlo simulation package. BRIMS is designed to produce data spanning a Q range from 0.0025 to 0.7 Angstrom(-1) in a single measurement by simultaneously using neutrons with wavelengths from 1 to 14.5 Angstrom in a time-of-flight mode. The effects of various collimation choices, including multiple confocal pinhole apertures, on count rate, resolution, and Q range have been characterized with simulations using spherical particle and delta-function scatterers. We compare the anticipated performance of BRIMS with that of the premier reactor-based SANS instrument, D22, at ILL. C1 Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Littrell, KC (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Littrell, Kenneth/D-2106-2013 OI Littrell, Kenneth/0000-0003-2308-8618 NR 8 TC 3 Z9 3 U1 1 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1480 EP S1482 DI 10.1007/s003390201932 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600182 ER PT J AU Littrell, KC Khalili, NR Campbell, M Sandi, G Thiyagarajan, P AF Littrell, KC Khalili, NR Campbell, M Sandi, G Thiyagarajan, P TI Structural characterization of activated carbon adsorbents prepared from paper mill sludge SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB Small-angle neutron scattering (SANS) was used to characterize the microstructure of a series of activated carbons produced from paper mill sludge using ZnCl2. The pores in these carbons are roughly rod-like; their radii and volumes increase with an increase in the amount of activating agent (ZnCl2) used for the production of the carbons. Contrast-variation SANS studies demonstrate the existence of two different phases, a zinc-rich particle phase and a bulk carbon phase with nanopores. Both phases are largely accessible to the solvent. The size and morphology of the pores and inclusions were determined from the SANS data. A conceptual model describing these carbons as consisting of amorphous carbon containing zinc-rich particles in large voids linked by narrow channels is proposed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. IIT, Dept Chem & Environm Engn, Chicago, IL 60616 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Littrell, KC (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Littrell, Kenneth/D-2106-2013 OI Littrell, Kenneth/0000-0003-2308-8618 NR 7 TC 4 Z9 4 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1403 EP S1405 DI 10.1007/s003390201429 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600157 ER PT J AU Lo Celso, F Triolo, A Bronstein, L Zwanziger, J Strunz, P Lin, JS Crapanzano, L Triolo, R AF Lo Celso, F Triolo, A Bronstein, L Zwanziger, J Strunz, P Lin, JS Crapanzano, L Triolo, R TI Investigating self-assembly and metal nanoclusters in aqueous di-block copolymers solutions SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID MICELLES AB Self-assembling properties of di-block copolymers/ surfactant hybrids in aqueous solution can be exploited to obtain metal nanoparticles stable dispersion. Results will be presented here for polystyrene-block-poly(ethylene oxide) solutions. A SANS structural investigation has been performed over different molecular weights of both hydrophilic and hydrophobic block, by varying temperature and concentration of the copolymer. A SAXS characterization of micellar systems containing Pt nanoparticles is reported. C1 Univ Palermo, Dept Phys Chem, I-90128 Palermo, Italy. HMI, BENSC, Berlin, Germany. Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lo Celso, F (reprint author), Univ Palermo, Dept Phys Chem, Viale Sci, I-90128 Palermo, Italy. RI Triolo, Alessandro/B-7760-2008; Lo Celso, Fabrizio/B-7554-2012; Triolo, Alessandro/A-4431-2012; Strunz, Pavel/D-1610-2011 OI Triolo, Alessandro/0000-0003-4074-0743; Strunz, Pavel/0000-0002-0829-4926 NR 8 TC 3 Z9 3 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S540 EP S542 DI 10.1007/s003390201527 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600180 ER PT J AU Majewski, J Smith, GS Burgess, I Zamlynny, V Szymanski, G Lipkowski, I Satija, S AF Majewski, J Smith, GS Burgess, I Zamlynny, V Szymanski, G Lipkowski, I Satija, S TI Neutron reflectivity studies of electric field driven structural transformations of surfactants SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID DODECYL-SULFATE; AU(111) ELECTRODE; WATER INTERFACE; ADSORPTION; MONOLAYER; BILAYERS AB We employed electrochemical methods together with in situ neutron reflectometry to describe the aggregation of organic surfactant molecules at a solid-liquid interface. The neutron reflectometry allowed us to determine the surface coverage, thickness, roughness and the relative positions of the aggregates. We found that the applied electric field may be used to reversibly manipulate the architecture of the organic molecules: from uniform monolayers to adsorbed hemimicelles. These studies are expected to provide a new insight into the roles played by entropic and electrostatic forces in complex fluids or biomaterials. C1 Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. Univ Guelph, Dept Chem, Guelph, ON N1G 2W1, Canada. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Majewski, J (reprint author), Los Alamos Natl Lab, LANSCE, POB 1663, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 13 TC 3 Z9 3 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S364 EP S367 DI 10.1007/s003390201640 PN 1 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600120 ER PT J AU Manson, JL Bordallo, HN Lynn, JW Huang, Q Feyerherm, R Loose, A Chapon, L Argyriou, DN AF Manson, JL Bordallo, HN Lynn, JW Huang, Q Feyerherm, R Loose, A Chapon, L Argyriou, DN TI Magnetic ordering and spin excitations in Mn(dca)(2)(pyz) [dca = N(CN)(2)(-), pyz = pyrazine] SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB We have studied the T- and H-dependent magnetism in Mn(dca)(2)(pyz) [dca = N(CN)(2)(-), pyz = pyrazine] using neutron-scattering methods. The crystal structure can be viewed as a molecular analog of ReO3, where 1D Mn-pyz-Mn chains connect 2D Mn(dca)(2) square sheets to form a 3D network. In zero field, the Mn2+ moments order antiferromagnetically below 2.53(2)K along the ac diagonal with a magnitude of 4.15(6)muB at 1.35 K. The field-dependent response of the [111] magnetic reflection is consistent with spin-flop and induced ferromagnetic phase transitions as previously observed in magnetization measurements. Diffuse-scattering studies indicated no evidence for low-dimensional spin correlations. Using quasielastic neutron scattering, a low-energy spin-wave excitation was observed at similar to 0.23 meV, which is similar to 1/6 the momentum transfer observed in Mn(dca)(2) owing to a reduced number of magnetic nearest neighbors. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Hahn Meitner Inst Berlin GmbH, D-14109 Berlin, Germany. Berlin Neutron Scattering Ctr, D-14109 Berlin, Germany. RP Manson, JL (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Bordallo, Heloisa/I-6836-2012; Feyerherm, Ralf/F-5487-2013 OI Bordallo, Heloisa/0000-0003-0750-0553; Feyerherm, Ralf/0000-0003-3034-4210 NR 7 TC 7 Z9 7 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S722 EP S724 DI 10.1007/s003390201662 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600241 ER PT J AU Mason, TE Crawford, RK Bunick, GJ Ekkebus, AE Belanger, D AF Mason, TE Crawford, RK Bunick, GJ Ekkebus, AE Belanger, D TI The spallation neutron source is taking shape SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The spallation neutron source (SNS) is rapidly taking shape at Oak Ridge National Laboratory in Oak Ridge, Tennessee. Funded by the U.S. Department of Energy (DOE), the SNS is being designed and built by six DOE laboratories: Argonne (instruments), Brookhaven (accumulator ring), Lawrence Berkeley (ion source), Los Alamos (warm linac and radio-frequency systems), Thomas Jefferson (cold linac), and Oak Ridge (target). Concrete foundations are being poured, and steel beams are piercing the sky above the ridge where the facility is being built. Instrument approval and development is progressing well, with prototypes undergoing testing and procurements beginning for approved instruments. The SNS and High Flux Isotope Reactor User Group Executive Committee are working to ensure consistent policies between the two Oak Ridge facilities. The project has sponsored and is continuing to sponsor several neutron-science-related workshops. In addition, project staff are participating in educational programs to encourage student interest in neutron science. C1 Oak Ridge Natl Lab, SNS Project, Oak Ridge, TN 37830 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. RP Mason, TE (reprint author), Oak Ridge Natl Lab, SNS Project, 701 Scarboro Rd, Oak Ridge, TN 37830 USA. RI Mason, Thomas/M-5809-2014 OI Mason, Thomas/0000-0003-1880-3971 NR 0 TC 4 Z9 5 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S11 EP S14 DI 10.1007/s003390201435 PN 1 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600005 ER PT J AU McQueeney, RJ Sarrao, JL Pagliuso, PG Stephens, PW Osborn, R AF McQueeney, RJ Sarrao, JL Pagliuso, PG Stephens, PW Osborn, R TI New oxygen lattice modes in the metallic region of La2-xSrxCuO4 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID DISPERSION; SUPERCONDUCTORS; TEMPERATURE; TRANSITION; PHONONS; OXIDES AB Inelastic neutron scattering measurements are presented that show a profound change in the spectrum of lattice vibrations when doping across the metal-insulator transition in La2-xSrxCuO4. In the metallic state, a new band of vibrations appears near 70 meV. These vibrations can be understood as the mixing of oxygen bond-stretching modes with doped holes in the CuO2 plane. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM mcqueeney@lanl.gov RI Osborn, Raymond/E-8676-2011; Pagliuso, Pascoal/C-9169-2012; McQueeney, Robert/A-2864-2016 OI Osborn, Raymond/0000-0001-9565-3140; McQueeney, Robert/0000-0003-0718-5602 NR 17 TC 1 Z9 1 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0947-8396 EI 1432-0630 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1621 EP S1623 DI 10.1007/s003390201836 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600228 ER PT J AU Mitchell, JF Ling, CD Millburn, JE Argyriou, DN Berger, A Medarde, M Miller, D Luo, ZP AF Mitchell, JF Ling, CD Millburn, JE Argyriou, DN Berger, A Medarde, M Miller, D Luo, ZP TI Heavily doped bilayer manganites: links among structure, charge, and spin SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID LA2-2XSR1+2XMN2O7; MAGNETORESISTANCE; LASR2MN2O7; TRANSITION AB Bilayer manganites La2-2xSr1+2xMn2O7 offer an exceptional opportunity to explore the connections among crystal structure, magnetic structure, and charge order. We have recently succeeded in synthesis of the phase diagram for x > 0.5, and have used both neutron and X-ray diffraction to explore this highly Mn4+-rich system. In particular, we find a progression of magnetic structures from the type-A layered antiferromagnetic (AF), through the type-C AF rod structure, and finally to the type-G 'rock salt' AF structure. We also discover an unexpected region in which no long-range magnetic order is found and discuss a possible frustration scenario based on incompatible orbital ordering. We also address the evolution of charge order in these materials. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Mitchell, JF (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM mitchell@anl.gov RI Ling, Chris D/B-2228-2009; Luo, Zhiping/C-4435-2014; Berger, Andreas/D-3706-2015 OI Ling, Chris D/0000-0003-2205-3106; Luo, Zhiping/0000-0002-8264-6424; Berger, Andreas/0000-0001-5865-6609 NR 20 TC 5 Z9 5 U1 0 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0947-8396 EI 1432-0630 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1776 EP S1778 DI 10.1007/s003390201766 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600277 ER PT J AU Moshopoulou, EG Sarrao, JL Pagliuso, PG Moreno, NO Thompson, JD Fisk, Z Ibberson, RM AF Moshopoulou, EG Sarrao, JL Pagliuso, PG Moreno, NO Thompson, JD Fisk, Z Ibberson, RM TI Comparison of the crystal structure of the heavy-fermion materials CeCoIn5, CeRhIn5 and CeIrIn5 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID SUPERCONDUCTIVITY AB The crystal structure of the recently discovered heavy-fermion (HF) superconductor CeCoIn5 (T-c = 2.3 K) has been determined by high-resolution neutron powder diffraction. It is tetragonal (space group P4/mmm), with lattice parameters a = 4.61292(9)Angstrom and c = 7.5513(2)Angstrom at ambient conditions. While CeCoIn5 is isostructural with the HF antiferromagnet CeRhIn5 and the HF superconductor CeIrIn5, its cell constants and its only variable positional parameter, zIn2, differ significantly from the corresponding ones of CeRhIn5 and CeIrIn5. As a result, the distortions of the cuboctabedron [CeIn3], which is the key structural unit in all three materials, are different in CeCoIn5 from the ones in CeRhIn5 and CeIrIn5. The compounds CeCoIn5 and CeIrIn5, which contain the most distorted (in one way or another) cuboctahedra [CeIn3] exhibit superconductivity at ambient pressure below 2.3 K and 0.4 K respectively. On the other hand, CeRhIn5, in which the [CeIn3] cuboctahedra are less distorted, and the parent compound of the materials CeTIn5, i.e. the cubic HF CeIn3, are antiferromagnets at ambient pressure with T-N congruent to 3.4 K and 10 K correspondingly. C1 Natl Ctr Sci Res Demokritos, Inst Mat Sci, Aghia Paraskevi 15310, Greece. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. RP Moshopoulou, EG (reprint author), Natl Ctr Sci Res Demokritos, Inst Mat Sci, Aghia Paraskevi 15310, Greece. RI Pagliuso, Pascoal/C-9169-2012; Moreno, Nelson/H-1708-2012; Ibberson, Richard/P-8397-2015 OI Moreno, Nelson/0000-0002-1672-4340; Ibberson, Richard/0000-0003-0007-706X NR 13 TC 20 Z9 20 U1 4 U2 20 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S895 EP S897 DI 10.1007/s003390201673 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600299 ER PT J AU Nagler, SE Lee, WT Moon, RM AF Nagler, SE Lee, WT Moon, RM TI Design and simulation of the CG1 beamline at HFIR SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID NEUTRON AB In the near future a super-critical hydrogen cold source will be installed in the HB4 beam tube of the High Flux Isotope Reactor (HFIR), Oak Ridge National Laboratory. The cold source will illuminate four neutron guides. Here we discuss the design and simulation of the guide CG1, dedicated to a new triple axis spectrometer. The conceptual design for the HFIR guides, including CG1, was aided by numerical calculations of neutron trajectories and acceptance diagrams. The CG1 guide consists of a partially trumpeting two-channel bender and a straight guide section. The design was subsequently modeled in detail from source to specimen, utilizing the McStas program. The lessons learned from the McStas simulations resulted in some minor but important changes in the design, and these were also verified using the original method of calculation. The resulting combination of guide and vertically focusing monochromator should deliver a beam with excellent spatial and angular distributions in and out of the scattering plane. The available intensity will enable the construction of a powerful spectrometer for incident energies as large as 20-25 meV. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Nagler, SE (reprint author), Oak Ridge Natl Lab, POB 2008 MS 6393, Oak Ridge, TN 37831 USA. RI Nagler, Stephen/B-9403-2010; Nagler, Stephen/E-4908-2010 OI Nagler, Stephen/0000-0002-7234-2339 NR 8 TC 0 Z9 0 U1 0 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1495 EP S1497 DI 10.1007/s003390101245 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600187 ER PT J AU Pappas, C Mezei, F Ehlers, G Campbell, IA AF Pappas, C Mezei, F Ehlers, G Campbell, IA TI Experimental evidence for dynamic scaling in spin glasses SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID ECHO; NSE AB Dynamics is the key to the understanding of glassy transitions. A detailed analysis of s(Q, t) in the spin glass system Au0.86Fe0.14 shows that at T-g the autocorrelation function decays as t(-x), with x similar to 0.12. Above T-g, s(Q, t) is then described by the form proposed by Ogielski: t(-x)exp(-(t/tau(0))(beta))). These results agree with predictions of large scale numerical simulations and are a direct confirmation of dynamic scaling in spin glasses. C1 HMI Berlin, D-14109 Berlin, Germany. Los Alamos Natl Lab, Los Alamos, NM USA. ILL, F-38042 Grenoble 9, France. Lab Verres, Montpellier, France. RP Pappas, C (reprint author), HMI Berlin, Glienickerstr 100, D-14109 Berlin, Germany. RI Ehlers, Georg/B-5412-2008 OI Ehlers, Georg/0000-0003-3513-508X NR 14 TC 3 Z9 3 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S907 EP S909 DI 10.1007/s003390201370 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600303 ER PT J AU Pappas, C Triolo, A Kischnik, R Mezei, F AF Pappas, C Triolo, A Kischnik, R Mezei, F TI Wide-angle NSE and TOF: the spectrometer SPAN at BENSC SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID SPIN-ECHO AB The cylindrical symmetry of the magnetic field configuration of SPAN allows for simultaneous neutron spin echo (NSE) measurements over the whole range of scattering angles accessible by a spectrometer. The open construction also allows for time-of-flight (TOF) measurements, which can be performed under the same conditions as NSE, in particular with polarization analysis. TOF and NSE spectra are then directly comparable with each other, without any adjustable parameters, covering a dynamic range of more than four orders of magnitude at a single wavelength. C1 HMI Berlin, D-14109 Berlin, Germany. Los Alamos Natl Lab, Los Alamos, NM USA. RP Pappas, C (reprint author), HMI Berlin, Glienickerstr 100, D-14109 Berlin, Germany. RI Triolo, Alessandro/B-7760-2008; Triolo, Alessandro/A-4431-2012 OI Triolo, Alessandro/0000-0003-4074-0743 NR 6 TC 1 Z9 1 U1 3 U2 10 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S286 EP S288 DI 10.1007/s003390201543 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600095 ER PT J AU Parizzi, AA Lee, WT Klose, F AF Parizzi, AA Lee, WT Klose, F TI Possibilities for polarized pulsed neutron instrumentation based on the time-of-flight spin-resonance energy filter SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB We present a new approach for dynamic energy filtering at spallation neutron sources, based on the original concept of the Drabkin spin-resonance flipper. The setup takes advantage of the neutron magnetic moment, and consists of a wavelength-selective magnetic resonator and a supermirror polarizer/analyzer system. We are proposing refinements (time dependence and revised magnetic field profiles) to the basic concepts of the setup, making it suitable for time-of-flight experiments at spallation neutron sources. We outline here possibilities for using this spin resonator as the core of new neutron instruments. C1 Argonne Natl Lab, IPNS SNS, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Spallat Neutron Source Project, Oak Ridge, TN 37830 USA. Fed Univ Rio De Janeiro, Dept Elect Engn, BR-90035150 Porto Alegre, RS, Brazil. RP Klose, F (reprint author), Argonne Natl Lab, IPNS SNS, 9700 S Cass Ave,Bld 360, Argonne, IL 60439 USA. NR 15 TC 2 Z9 2 U1 1 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1607 EP S1609 DI 10.1007/s003390201794 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600223 ER PT J AU Parizzi, AA Lee, WT Klose, F AF Parizzi, AA Lee, WT Klose, F TI Modeling the neutron spin-flip process in a time-of-flight spin-resonance energy filter SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB A computer program for modeling the neutron spin-flip process in a novel time-of-flight (TOF) spin-resonance energy filter has been developed. The software allows studying the applicability of the device in various areas of spallation neutron scattering instrumentation, for example as a dynamic TOF monochromator. The program uses a quantum-mechanical approach to calculate the local spin-dependent spectra and is essential for optimizing the magnetic field profiles along the resonator axis. C1 Oak Ridge Natl Lab, Spallat Neutron Source Project, Oak Ridge, TN 37831 USA. Argonne Natl Lab, Spallat Neutron Source Project, Argonne, IL 60439 USA. Univ Fed Rio Grande Sul, Dept Elect Engn, BR-90046900 Porto Alegre, RS, Brazil. RP Klose, F (reprint author), Oak Ridge Natl Lab, Spallat Neutron Source Project, Oak Ridge, TN 37831 USA. NR 10 TC 2 Z9 2 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1498 EP S1501 DI 10.1007/s003390201793 PN 2 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600188 ER PT J AU Petrenko, OA Balakrishnan, G Paul, DM Yethiraj, M Klenke, J AF Petrenko, OA Balakrishnan, G Paul, DM Yethiraj, M Klenke, J TI Field-induced transitions in the highly frustrated magnet gadolinium gallium garnet - long- or short-range order? SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID LIQUID AB In gadolinium gallium garnet (GGG) the antiferromagnetically interacting Gd ions are located on two corner-sharing triangular sublattices. The magnetic system is therefore highly frustrated and does not order in zero field. Antiferromagnetic (AF) order can only be induced by the application of an external magnetic field. We have measured the magnetic diffraction pattern of a single crystal of GGG at temperatures between 50mK and 0.9K in fields of up to 4 T. These experiments reveal that the H-T phase diagram has a much more complicated nature than previously assumed. Three groups of magnetic Bragg peaks were found: strong ferromagnetic peaks, saturating in fields above 2.5 T, strong AF peaks with a maximum intensity at the lower-field phase boundary around 0.6 T and weak AF peaks which have a maximum intensity at the upper phase boundary around 1.5 T. The widths of the strong AF peaks are limited by the instrument resolution only in the vicinity of the lower phase boundary. C1 Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Hahn Meitner Inst Berlin GmbH, Berlin Neutron Scattering Ctr, D-14109 Berlin, Germany. RP Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. EM O.Petrenko@warwick.ac.uk RI Petrenko, Oleg/E-2717-2013; Balakrishnan, Geetha/P-5977-2016 OI Petrenko, Oleg/0000-0003-1529-303X; Balakrishnan, Geetha/0000-0002-5890-1149 NR 9 TC 6 Z9 6 U1 1 U2 5 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0947-8396 EI 1432-0630 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S760 EP S762 DI 10.1007/s003390201579 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600254 ER PT J AU Popovici, M Stoica, AD AF Popovici, M Stoica, AD TI Neutron imaging with multi-wafer monochromators SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID ELASTICALLY BENT SILICON; CRYSTAL DIFFRACTOMETER; SCATTERING; SPECTROMETRY; SANS AB Multi-wafer monochromators for neutron scattering have been developed at MURR. Units made from commercial thin silicon [100] wafers and from non-standard [511] and [110] wafers were fabricated for stress-mapping machines at MURR, NIST and ORNL. The phase-space optics of multi-wafer assemblies was worked out. This revealed that, with thick packets of wafers, neutron imaging can be done at the spatial resolution of a single thin wafer. The imaging may be dispersive (as with prisms), with respect to the neutron wavelength, direction, or a combination of these, but it may also be non-dispersive (as with mirrors). Experiments have confirmed these conclusions. Dispersive and nondispersive images were obtained with multi-wafer units at spatial resolutions comparable to those of single wafers. For non-dispersive imaging the acceptance window indeed did not depend on the neutron wavelength. C1 Univ Missouri, Res Reactor, MURR, Columbia, MO 65211 USA. Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37831 USA. RP Popovici, M (reprint author), Univ Missouri, Res Reactor, MURR, Columbia, MO 65211 USA. RI Stoica, Alexandru/K-3614-2013 OI Stoica, Alexandru/0000-0001-5118-0134 NR 20 TC 4 Z9 4 U1 0 U2 6 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S273 EP S276 DI 10.1007/s003390201719 PN 1 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600091 ER PT J AU Proffen, T Billinge, SJL AF Proffen, T Billinge, SJL TI Probing the local structure of doped manganites using the atomic pair distribution function SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID NEUTRON-SCATTERING; POLARON FORMATION; X-RAY; LA1-XCAXMNO3; PHASE; DIFFRACTION; DISTORTIONS; REFINEMENT AB We have used atomic pair distribution function (PDF) analysis based on neutron powder diffraction data to investigate the local structure of the colossal magnetoresistant marganite La(0.75)Ca(0.25)MnO(3) as a function of temperature. In the doping range 0.17 < x < 0.5 these materials show a metal-to-insulator transition, transforming from a ferromagnetic metal (FM) at low temperature to a paramagnetic insulator (PI). We can probe the charge distribution of the sample using the PDF by searching for evidence of Jahn-Teller (JT) distorted octahedra, implying the presence of Mn(3+) ions. A two-phase model based on the local structures of the FM and PI phases was used to refine the experimental PDFs quantitatively. We observe the co-existence of both phases over a wide temperature range: approximately 10% of the localized JT phase (PI) is present even at the lowest temperature (T = 20 K), whereas at room temperature nearly half of the sample remains in the delocalized (FM) phase. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. RP Proffen, T (reprint author), Los Alamos Natl Lab, LANSCE-12,MS H805, Los Alamos, NM 87545 USA. EM tproffen@lanl.gov RI Lujan Center, LANL/G-4896-2012; Proffen, Thomas/B-3585-2009 OI Proffen, Thomas/0000-0002-1408-6031 NR 18 TC 4 Z9 4 U1 0 U2 6 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1770 EP S1772 DI 10.1007/s003390201846 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600275 ER PT J AU Proffen, T Egami, T Billinge, SJL Cheetham, AK Louca, D Parise, JB AF Proffen, T Egami, T Billinge, SJL Cheetham, AK Louca, D Parise, JB TI Building a high resolution total scattering powder diffractometer upgrade of NPD at MLNSC SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID PAIR DISTRIBUTION FUNCTION; X-RAY; NEUTRON-SCATTERING; REFINEMENT AB The neutron powder diffractometer NPD at the Manuel Lujan Neutron Scattering Center (MLNSC) at Los Alamos National Laboratory is the neutron powder diffractometer with the highest resolution in the United States. We are currently upgrading NPD by adding a large number of position-sensitive detectors in the backscattering position. The upgraded instrument will make it possible to collect data from a powder sample over a wide range in Q with high Q resolution at high data rates. This design will optimize the instrument for total scattering measurements, including Bragg as well as diffuse scattering, allowing us to determine the crystallographic average structure as well as the local structure, often responsible for the properties of complex materials. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11790 USA. RP Los Alamos Natl Lab, LANSCE-12,MS H805, Los Alamos, NM 87545 USA. EM tproffen@lanl.gov RI Lujan Center, LANL/G-4896-2012; Proffen, Thomas/B-3585-2009 OI Proffen, Thomas/0000-0002-1408-6031 NR 16 TC 79 Z9 79 U1 0 U2 7 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0947-8396 EI 1432-0630 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S163 EP S165 DI 10.1007/s003390201929 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600053 ER PT J AU Rehm, C Agamalian, M AF Rehm, C Agamalian, M TI Flux gain for a next-generation neutron reflectometer resulting from improved supermirror performance SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB Next-generation spallation neutron source facilities will offer instruments with unprecedented capabilities through simultaneous enhancement of source power and usage of advanced optical components. The Spallation Neutron Source (SNS), already under construction at Oak Ridge National Laboratory and scheduled to be completed by 2006, will provide greater than an order of magnitude more effective source flux than current state-of-the-art facilities, including the most advanced research reactors. An additional order of magnitude gain is expected through the use of new optical devices and instrumentation concepts. Many instrument designs require supermirror neutron guides with very high critical angles for total reflection. In this contribution, we will discuss how the performance of a modem neutron-scattering instrument depends on the efficiency of these supermirrors. We summarize cur-rent limitations of supermirror coatings and outline ideas for enhancing their performance, particularly for improving the reflectivity at the critical wave-vector transfer. A simulation program has been developed which allows different approaches for supermirror designs to be studied. Expected instrument performance gains are calculated for the example of the SNS reflectometer. C1 Oak Ridge Natl Lab, Spallat Neutron Source Project, Oak Ridge, TN 37831 USA. RP Rehm, C (reprint author), Argonne Natl Lab, IPNS, SNS, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Agamalian, Michael/0000-0002-9112-2534 NR 6 TC 0 Z9 2 U1 1 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1483 EP S1485 DI 10.1007/s003390201724 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600183 ER PT J AU Russina, O Russina, M Mezei, F Lechner, R Pieper, J Desmedt, A AF Russina, O Russina, M Mezei, F Lechner, R Pieper, J Desmedt, A TI Dynamic correlations around the glass transition in systems with different degrees of fragility SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID STRUCTURAL RELAXATION; FORMERS; TIME AB We have investigated two ionic salt systems with different degrees of fragility, Ca0.4K0.6(NO3)(1.4) (CKN) and ZnCl2, by cold-neutron spectroscopy. The spectra were studied in detail around the glass-transition temperatures. Harmonic vibrations dominate the dynamics in both systems below the glass transition. With increasing temperature a strong anharmonic additional intensity was observed in the picosecond range in both systems. The results of our study show correlations between the low-energy excitations and the degree of fragility: harmonic vibrations are better pronounced in less fragile systems, while the anharmonic picosecond dynamics are stronger in fragile glass-forming liquids. C1 Hahn Meitner Inst Berlin GmbH, HMI, D-14109 Berlin, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Russina, O (reprint author), Hahn Meitner Inst Berlin GmbH, HMI, Glienicker Str 100, D-14109 Berlin, Germany. RI Russina, Margarita/E-9886-2016; Russina, Olga/G-9780-2012 OI Russina, Margarita/0000-0003-2067-606X; NR 9 TC 1 Z9 1 U1 1 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1192 EP S1193 DI 10.1007/s003390201689 PN 2 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600086 ER PT J AU Santisteban, JR Edwards, L Priesmeyer, HG Vogel, S AF Santisteban, JR Edwards, L Priesmeyer, HG Vogel, S TI Comparison of Bragg-edge neutron-transmission spectroscopy at ISIS and LANSCE SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The Bragg edges appearing in the neutron-transmission spectra of a polycrystalline material represent its coherent-scattering response at 2theta = 180degrees. Structural information such as texture, phase content or strain may be derived from the intensity and position of these edges. Transmission diffractometers have been recently developed at both LANSCE and ISIS and used for studying the dynamics of phase transformations and strain imaging, respectively. The incident neutron spectra vary due to the different neutron moderators and flight paths used in the two instruments. This paper reports a comparative study of the two instruments and their analysis software. C1 Open Univ, Dept Mat Engn, Milton Keynes, Bucks, England. Univ Kiel, Inst Expt & Appl Phys, D-24118 Kiel, Germany. Los Alamos Natl Lab, LANSCE, Los Alamos, NM USA. RP Santisteban, JR (reprint author), Open Univ, Dept Mat Engn, Milton Keynes, Bucks, England. RI Lujan Center, LANL/G-4896-2012; Edwards, Lyndon/D-1916-2013; OI Edwards, Lyndon/0000-0001-7526-6020; Vogel, Sven C./0000-0003-2049-0361 NR 9 TC 5 Z9 5 U1 1 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1616 EP S1618 DI 10.1007/s003390201562 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600226 ER PT J AU Seeger, PA Daemen, LL AF Seeger, PA Daemen, LL TI Mosaic crystal algorithm for Monte Carlo simulations SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID TOOL AB An algorithm is presented for calculating reflectivity, absorption, and scattering of mosaic crystals in Monte Carlo simulations of neutron instruments. The algorithm uses multi-step transport through the crystal with an exact solution of the Darwin equations at each step. It relies on the kinematical model for Bragg reflection (with parameters adjusted to reproduce experimental data). For computation of thermal effects (the Debye-Waller factor and coherent inelastic scattering), an expansion of the Debye integral as a rapidly converging series of exponential terms is also presented. Any crystal geometry and plane orientation may be treated. The algorithm has been incorporated into the neutron instrument simulation package NISP. C1 Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RP Seeger, PA (reprint author), 239 Loma Escolar, Los Alamos, NM 87544 USA. RI Lujan Center, LANL/G-4896-2012 NR 11 TC 5 Z9 5 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1458 EP S1461 DI 10.1007/s003390201792 PN 2 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600175 ER PT J AU Shapiro, SM Bao, W Raymond, S Lee, SH Motoya, K AF Shapiro, SM Bao, W Raymond, S Lee, SH Motoya, K TI Observation of linear spin wave dispersion in the reentrant spin glass Fe0.7Al0.3 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB Fe0.7Al0.3 is a reentrant spin glass, which undergoes a transition from a paramagnet to a disordered ferromagnet at T-c similar to 500 K; at a lower temperature the spins progressively freeze and it exhibits a spin-glass-like behavior. In the ferromagnetic phase spin waves with a q(2) dispersion are observed at small q, which broaden rapidly and become diffusive beyond a critical wave vector q(0). On cooling the spin waves also disappear and a strong elastic central peak develops. For measurements around the (1, 1, 1) Bragg peak, a new sharp excitation is observed which has a linear dispersion behavior. It disappears above T-c, but persists throughout the spin-glass phase. It is not present in the stoichiometric Fe3Al material. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CEA Genoble, DRFMC, SPSMS, F-38054 Grenoble, France. NIST, Gaithersburg, MD 20899 USA. Sci Univ Tokyo, Noda, Chiba 278, Japan. RP Shapiro, SM (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Bao, Wei/E-9988-2011 OI Bao, Wei/0000-0002-2105-461X NR 6 TC 1 Z9 1 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S859 EP S861 DI 10.1007/s003390201670 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600287 ER PT J AU Sitepu, H Schmahl, WW Von Dreele, RB AF Sitepu, H Schmahl, WW Von Dreele, RB TI Use of the generalized spherical harmonic model for describing crystallographic texture in polycrystalline NiTi shape-memory alloy with time-of-flight neutron powder diffraction data SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID MARTENSITE AB We present a feasibility study to extract quantitative texture and precise crystal structure information of poly-crystalline monoclinic NiTi shape-memory alloys from a simultaneous refinement of 52 time-of-flight neutron-diffraction patterns taken in 13 orientations in the diffractometer. The multiple-data-set capabilities and the generalized spherical harmonic texture model of the GSAS program system were employed. C1 Ruhr Univ Bochum, Inst Geol Mineral & Geophys, D-44780 Bochum, Germany. Los Alamos Natl Lab, LANSCE 12, Los Alamos, NM 87545 USA. RP Sitepu, H (reprint author), ESRF, ILL, FAME38, BP 156, F-38042 Grenoble, France. RI Schmahl, Wolfgang/J-7571-2012 OI Schmahl, Wolfgang/0000-0002-0165-5952 NR 10 TC 11 Z9 11 U1 3 U2 9 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1676 EP S1678 DI 10.1007/s003390201934 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600245 ER PT J AU Smee, SA Orndorff, JD Scharfstein, GA Qiu, Y Brand, PC Broholm, CL Anand, DK AF Smee, SA Orndorff, JD Scharfstein, GA Qiu, Y Brand, PC Broholm, CL Anand, DK TI MACS low-background doubly focusing neutron monochromator SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB A novel doubly focusing neutron monochromator has been developed as part of the Multi-Analyzer Crystal Spectrometer (MACS) at the NIST Center for Neutron Research. The instrument utilizes a unique vertical focusing element that enables active vertical and horizontal focusing with a large, 357-crystal (1428 cm(2)), array. The design significantly reduces the amount of structural material in the beam path as compared to similar instruments. Optical measurements verify the excellent focal performance of the device. Analytical and Monte Carlo simulations predict that, when mounted at the NIST cold-neutron source, the device should produce a monochromatic beam (DeltaE = 0.2 meV) with flux phi > 108 n/cm(2) S. C1 Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37830 USA. RP Smee, SA (reprint author), Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. RI Broholm, Collin/E-8228-2011 OI Broholm, Collin/0000-0002-1569-9892 NR 5 TC 1 Z9 1 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S255 EP S257 DI 10.1007/s003390201658 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600085 ER PT J AU Stoica, AD Wang, XL AF Stoica, AD Wang, XL TI Towards 0.1-mm spatial resolution in neutron diffractometry SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID LENS AB A design goal for VULCAN, the SNS engineering neutron diffractometer, is to enable spatial mapping with 0.1-mm resolution. Because the targeted applications often involve the use of large samples or special environments, slits cannot be used for this purpose. In this paper, methods to achieve 0.1-mm spatial resolution are outlined. For the incident beam, a new compact focusing device is proposed. The device is made of a stack of bent silicon wafers, each having a reflective multilayer (supermirror) deposited on one side and a neutron-absorbing layer on the other side. The optimal design to minimize the optical spatial aberrations is discussed and Monte Carlo simulation results are presented. For the diffracted beam, imaging devices made from thick packets of diffracting bent silicon wafers (known as Bragg mirrors) could be used. The requirements to achieve sharp imaging together with a large phase-space acceptance window are discussed and preliminary testing results are presented. C1 Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37831 USA. RP Stoica, AD (reprint author), Oak Ridge Natl Lab, Spallat Neutron Source, 701 Scarboro Rd, Oak Ridge, TN 37831 USA. RI Wang, Xun-Li/C-9636-2010; Stoica, Alexandru/K-3614-2013 OI Wang, Xun-Li/0000-0003-4060-8777; Stoica, Alexandru/0000-0001-5118-0134 NR 8 TC 3 Z9 3 U1 0 U2 6 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S258 EP S260 DI 10.1007/s003390201729 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600086 ER PT J AU Thiyagarajan, P Fan, L AF Thiyagarajan, P Fan, L TI Influence of carbonate ions on the micellization behavior in triblock copolymer solution SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID DYNAMICS; MICELLES AB SANS was used to investigate the micellization behavior of triblock copolymers (1768, F88 and F108) as functions of carbonate ion concentration and temperature. SANS data were fitted to determine the sizes of the core and corona, inter-micelle distance, association number and the volume fraction of the micelles. As the polymer molecular weight increases, the core radius and the radius of gyration (R-g) of the corona and the inter-micelle distance increase. The carbonate ion concentration and polymer molecular weight have dramatic influence on the temperatures at which the micellization and spherical-to-cylindrical micelle transformation occur. The mechanism by which this phenomenon occurs in these solutions is through a gradual dehydration of polymers with increasing carbonate concentration and/or temperature. weights (F68, F88 and F108) as a function of temperature, both in neat and carbonate ion solutions. We analyzed the SANS data using the modified version [6] of the formalism developed by Pedersen and Gerstenberg [7] and obtained information on the micelle association number, core radius, corona R-g, volume fraction of micelles and inter-micelle distance. C1 Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. RP Thiyagarajan, P (reprint author), Argonne Natl Lab, IPNS, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 4 Z9 4 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S525 EP S527 DI 10.1007/s003390201526 PN 1 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600175 ER PT J AU Tulk, CA Klug, DD Svensson, EC Sears, VF Katsaras, J AF Tulk, CA Klug, DD Svensson, EC Sears, VF Katsaras, J TI The low-frequency density of states for amorphous and crystalline ices SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID VIBRATIONAL-MODES; GLASS; SCATTERING; SPECTRUM; DYNAMICS AB Incoherent inelastic neutron scattering studies have been performed on two amorphous polymorphs and two crystalline polymorphs of ice, including high-density amorphous (hda) ice. Subsequent annealing cycles allowed data to be collected from low-density amorphous ice (1da), and crystalline ices Ic and Ih. Data were collected between 5 and 80 K for hda, and between 5 and 120 K for the other phases. The low-frequency (nu < 1 THz) densities of states of the four phases are compared. The data illustrate clearly an excess number of modes in the hda density of states at 5 K centered at 0.65 THz. The magnitude of the excess g(v) is considerably reduced upon heating the sample from 5 to 20 K. Above 60 K the density of states of hda was found to exhibit predominantly a Debye behavior, g(nu) alpha Anu(2), as nu --> 0 THz. No such excess modes were observed in 1da or the two crystalline phases studied. C1 Natl Res Council Canada, Steacie Inst Mol Sci, Ottawa, ON K1A 0R6, Canada. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tulk, CA (reprint author), Natl Res Council Canada, Steacie Inst Mol Sci, 100 Sussex Dr, Ottawa, ON K1A 0R6, Canada. EM ctulk@anl.gov RI Tulk, Chris/R-6088-2016; OI Tulk, Chris/0000-0003-3400-3878; Katsaras, John/0000-0002-8937-4177 NR 14 TC 8 Z9 8 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1185 EP S1187 DI 10.1007/s003390201688 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600084 ER PT J AU Velthuis, SGET Felcher, GP Kim, S Schuller, IK AF Velthuis, SGET Felcher, GP Kim, S Schuller, IK TI Magnetic profiles and coupling in Fe/Cr(110) superlattices SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID EXCHANGE; MAGNETORESISTANCE AB In epitaxial Fe/Cr superlattices the coupling between the Fe layers oscillates between antiferromagnetic (AFM) and ferromagnetic as a function of the Cr layer thickness t(Cr). The period of the oscillation is the same for superlattices grown with (211) and (100) orientations. We measured the coupling of Fe/Cr(I 10) superlattices consisting of three identical Fe layers. The magnetization curves were characterized by two to four levels, M/M-s +/-1 or +/-1/3. Polarized neutron reflectometry identified the direction of the magnetization of each Fe layer and showed that the levels M/M-s = +/-1/3 were not always due to AFM alignment of the central layer, but rather it was found that, in spite of the structural similarity, the bottom Fe layer had a different coupling strength from the top Fe layer. The magnetic coupling must be sensitive to small structural differences at the interface. Furthermore, the measurements indicate an unexpected periodicity for Fe/Cr(110) superlattices. C1 Argonne Natl Lab, Div Sci Mat, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Velthuis, SGET (reprint author), Argonne Natl Lab, Div Sci Mat, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI te Velthuis, Suzanne/I-6735-2013 OI te Velthuis, Suzanne/0000-0002-1023-8384 NR 11 TC 1 Z9 1 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1563 EP S1565 DI 10.1007/s003390201772 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600209 ER PT J AU Wagner, W Eastman, JA AF Wagner, W Eastman, JA TI Characterization of yttria-stabilized zirconia coatings with controlled nanometer-sized porosity by SANS SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID NANOCRYSTALLINE AB Coatings of cubic yttria-stabilized zirconia (YSZ) grown on alumina (Al2O3) substrates were characterized with regard to structure, grain morphology and porosity. The present study shows that the deposition of YSZ films onto polycrystalline Al2O3 substrates by MOCVD (metal organic chemical vapor deposition) under the given deposition conditions leads to nanostructured film morphologies with mean grain sizes in the range 10-14 nm when the substrate temperature is 450-550 degreesC. Small angle neutron scattering (SANS) was applied to analyze the pore structure in the nanometer range, revealing that the films have a pronounced, very finely dispersed porosity. For substrate temperatures ranging from 425-500degreesC the average pore diameters are between 0.7 and 1 nm. For higher substrate temperatures, the pore size increases, reaching an average diameter of 5.4 nm at a substrate temperature of 600 degreesC. C1 Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Wagner, W (reprint author), Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RI Eastman, Jeffrey/E-4380-2011; OI Eastman, Jeff/0000-0002-0847-4265 NR 4 TC 2 Z9 2 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1007 EP S1009 DI 10.1007/s003390101176 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600026 ER PT J AU Wakabayashi, N Shimomura, S Dai, P Fernandez-Baca, JA Tomioka, Y Tokura, Y AF Wakabayashi, N Shimomura, S Dai, P Fernandez-Baca, JA Tomioka, Y Tokura, Y TI Polaron lifetime in La0.75Ca0.25MnO3 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID RAY DIFFUSE-SCATTERING AB As part of continuing effort to accurately characterize the nature of the polaron in perovskite manganese oxides, quasielastic neutron scattering measurements were performed on a single-crystal sample of La0.75Ca0.25MnO3. Energy scans at the wavevector for the short-range correlation peak in the paramagnetic insulator phase show that the line widths are resolution-limited at all temperatures. In contrast, the line width of the diffuse part of the scattering due to uncorrelated polarons was found to be much larger, as large as 4 meV (FWHM), and of the same order of magnitude as that of magnetic scattering. Results of the measurements are interpreted on the basis of a scattering function consisting of terms for isolated polarons and for polarons in clusters. C1 Keio Univ, Dept Phys, Kohoku Ku, Yokohama, Kanagawa 2238522, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Joint Res Ctr Atom Technol, Tsukuba, Ibaraki 3058562, Japan. Univ Tokyo, Dept Appl Phys, Tokyo 1138656, Japan. RP Wakabayashi, N (reprint author), Keio Univ, Dept Phys, Kohoku Ku, 3-14-1 Hiyoshi, Yokohama, Kanagawa 2238522, Japan. RI Dai, Pengcheng /C-9171-2012; Tokura, Yoshinori/C-7352-2009; Fernandez-Baca, Jaime/C-3984-2014 OI Dai, Pengcheng /0000-0002-6088-3170; Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 6 TC 1 Z9 1 U1 1 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1782 EP S1784 DI 10.1007/s003390201848 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600279 ER PT J AU Winn, BL Shapiro, SM Erwin, R Schagel, DL Lograsso, T AF Winn, BL Shapiro, SM Erwin, R Schagel, DL Lograsso, T TI Anomalous phonon damping in the high temperature shape memory alloy Ti50Pd42Cr8 SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID PHASE AB Neutron-scattering measurements of the high temperature shape memory alloy Ti50Pd50-xCrx were performed to probe the phonon precursors to the martensitic transformation. For x = 0, the transformation temperature, T-M, is similar to800 K [1] and, for the composition studied, x = 8%, it is reduced to similar to400 K. Above this temperature the crystal possesses a simple CsCl-type cubic structure. Transverse acoustic phonons propagating along the [ 0] direction with atomic displacements along [-xixi0] were studied at temperatures up to 873 K. The phonons are well defined near the zone center but, for xi > 0.15, they are strongly over-damped near the transition temperature, and become better defined at higher temperatures. An elastic peak develops in the cubic phase at xi = 0.22 and increases in intensity as T-M is approached. However, the phonons do not show any characteristic anomaly at this particular xi. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Winn, BL (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Winn, Barry/A-5065-2016 OI Winn, Barry/0000-0001-6383-4318 NR 7 TC 7 Z9 7 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1182 EP S1184 DI 10.1007/s003390201687 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600083 ER PT J AU Yethiraj, M AF Yethiraj, M TI Anomalous phonon behaviour in V3Si SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID NEUTRON-SCATTERING AB In earlier studies of phonons in V3Si, a gradual softening of the (hh0) branch was observed and attributed to the martensitic transition in this compound, which precedes the onset of superconductivity by a few degrees K. In this work, the temperature dependence of the transverse acoustic (TA) branch along the hh0 direction was studied in greater detail and it is shown that while the TA hh0 mode starts to soften at relatively high temperatures (> 200 K), an anomalous softening, which is rather localized in q, occurs just below T-c. The intensity of this soft-phonon peak correlates extremely well with the onset of the superconducting phase and appears to vary as the order parameter with temperature and applied field. The similarities in the phonon softening and Fermi-surface anisotropy between this compound and the rare-earth nickel borocarbides suggest the existence of a common mechanism for the superconducting transition. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Yethiraj, M (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 8 TC 0 Z9 0 U1 2 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1210 EP S1212 DI 10.1007/s003390201871 PN 2 PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 649QN UT WOS:000181219600092 ER PT J AU Zheludev, A AF Zheludev, A TI Interacting quantum spin chains SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY ID DIMENSIONAL S=1/2 ANTIFERROMAGNET; LONG-RANGE ORDER; NEUTRON-SCATTERING; HALDANE-GAP; EXCITATION SPECTRUM; COMPOUND KCUF3; GROUND-STATE; DOPED CUGEO3; DYNAMICS; FIELD AB A brief review of recent advances in neutron scattering studies of low-dimensional quantum magnets is followed by a particular example. The separation of single-particle and continuum states in the weakly coupled S = 1/2 chains system BaCu2Si2O7 is described in some detail. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Zheludev, A (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 58 TC 6 Z9 6 U1 2 U2 8 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S1 EP S5 DI 10.1007/s003390201382 PN 1 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600003 ER PT J AU Zsigmond, G Lieutenant, K Mezei, F AF Zsigmond, G Lieutenant, K Mezei, F TI Monte Carlo simulation of single-crystal spectroscopy and diffraction at spallation sources SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Neutron Scattering CY SEP 09-13, 2001 CL MUNICH, GERMANY AB The simulation package VITESS offers an advanced Monte Carlo technique for the numerical calculation of flux, count rates and resolution functions for single-crystal neutron spectrometers and diffractometers. The comparison of various moderator (decoupled-poisoned, decoupled and coupled) and target (short and long pulse) options for backscattering spectrometers and single-crystal diffractometers at the future European Spallation Source (ESS) is one of the main applications of VITESS. Single crystal instrument components highly determine both the wavelength selection and the intensities measured at the detectors. Both intensity and beam divergence are highly influenced by the focussing geometry of the monochromators or analysers. Detailed resolution calculations are presented. Crystal-sample modules were implemented to analyse the options mentioned above for single-crystal diffraction at the ESS. We made a detailed line-shape analysis of the detector signals. C1 Hahn Meitner Inst Berlin GmbH, D-14109 Berlin, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Zsigmond, G (reprint author), Hahn Meitner Inst Berlin GmbH, Glienicker Str 100, D-14109 Berlin, Germany. NR 5 TC 2 Z9 2 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2002 VL 74 SU S BP S224 EP S225 DI 10.1007/s003390201740 PN 1 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 654MA UT WOS:000181499600074 ER PT J AU Bonneau, F Combis, P Rullier, JL Vierne, J Pellin, M Savina, M Broyer, M Cottancin, E Tuaillon, J Pellarin, M Gallais, L Natoli, JV Perra, M Bercegol, H Lamaignere, L Loiseau, M Donohue, JT AF Bonneau, F Combis, P Rullier, JL Vierne, J Pellin, M Savina, M Broyer, M Cottancin, E Tuaillon, J Pellarin, M Gallais, L Natoli, JV Perra, M Bercegol, H Lamaignere, L Loiseau, M Donohue, JT TI Study of UV laser interaction with gold nanoparticles embedded in silica SO APPLIED PHYSICS B-LASERS AND OPTICS LA English DT Article ID INDUCED DAMAGE SIMULATIONS; THIN-FILMS; IONIZATION; BREAKDOWN; SOLIDS; DIELECTRICS; IRRADIATION; SURFACES; DEFECTS; CRACKS AB In order to resolve problems concerning the understanding and the control of laser-induced damage of silica optical elements, a collaboration between the CEA and different university laboratories has been undertaken. Ultra-pure silica model samples, seeded with gold nanoparticles whose diameter did not exceed 5 nm, were prepared. The aim in using these samples was to observe the mechanism of damage initiation that could be attributed to inclusions of nanometric size. This paper presents the different steps encountered during this study: preparation of the samples, the laser-induced damage tests, the Nomarski and atomic-force microscope observations of this damage and a series of experiments using a time-of-flight mass spectrometer at Argonne National Laboratory. The experimental data are then interpreted, and, in particular, compared to numerical simulations. A very encouraging result is the existence of a pre-damage phase at very low fluences that is not detectable by classical optical devices. The experimental means developed for such model samples should be transposable to the analysis of industrial glasses. C1 CEA DAM Ile de France, Dept Phys Theor & Appl, F-91680 Bruyeres Le Chatel, France. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Lyon 1, Ctr Agregat LASIM & DPM, F-69622 Villeurbanne, France. Univ Lyon 1, CNRS, F-69622 Villeurbanne, France. Inst Fresnel, F-13397 Marseille, France. CEA, CESTA, Dept Lasers Puissance, F-33114 Le Barp, France. CEN Bordeaux Gradignan, F-33175 Gradignan, France. RP Bonneau, F (reprint author), CEA DAM Ile de France, Dept Phys Theor & Appl, BP 12, F-91680 Bruyeres Le Chatel, France. RI Pellin, Michael/B-5897-2008; Cottancin, Emmanuel/M-4172-2015 OI Pellin, Michael/0000-0002-8149-9768; NR 37 TC 46 Z9 50 U1 1 U2 13 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0946-2171 J9 APPL PHYS B-LASERS O JI Appl. Phys. B-Lasers Opt. PD DEC PY 2002 VL 75 IS 8 BP 803 EP 815 DI 10.1007/s00340-002-1049-7 PG 13 WC Optics; Physics, Applied SC Optics; Physics GA 648DJ UT WOS:000181134300001 ER PT J AU Roy, S Lucht, RP Mcilroy, A AF Roy, S Lucht, RP Mcilroy, A TI Mid-infrared polarization spectroscopy of carbon dioxide SO APPLIED PHYSICS B-LASERS AND OPTICS LA English DT Article ID DEGENERATE 4-WAVE-MIXING SPECTROSCOPY; MOLECULAR GAS-MIXTURES; FLAMES; OH; TEMPERATURE; SATURATION; LASER AB The use of mid-infrared polarization spectroscopy (PS) for the detection of CO2 has been demonstrated. The P(13) and P(14) resonances of the (00(0) 0) --> (10(0) 1) transition of CO2 were probed using a single-mode optical parametric generator system to produce a high-intensity laser beam at approximately 2.7 mum. The experiments were performed in an atmospheric pressure CO2 jet and also in a sub-atmospheric pressure gas cell. The experimental results were compared with the results of the time-dependent density-matrix equations using direct numerical integration. The Zeeman-state structure of the upper and lower energy levels was included in the multi-state formulation of the density-matrix equations. Fifty-eight Zeeman states and two bath levels were included in the numerical analysis of the P(14) transition. The measured and calculated PS line shapes were in good agreement, and the absolute experimental signal level agreed with the theoretical calculation to within a factor of five. 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), Purdue Univ, Sch Mech Engn, W Lafayette, IN 47807 USA. NR 37 TC 20 Z9 20 U1 0 U2 6 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0946-2171 J9 APPL PHYS B-LASERS O JI Appl. Phys. B-Lasers Opt. PD DEC PY 2002 VL 75 IS 8 BP 875 EP 882 DI 10.1007/s00340-002-1034-1 PG 8 WC Optics; Physics, Applied SC Optics; Physics GA 648DJ UT WOS:000181134300012 ER PT J AU de Villiers, D Nortier, M Richter, W AF de Villiers, D Nortier, M Richter, W TI Experimental and theoretical excitation functions for Br-nat(p, x) reactions SO APPLIED RADIATION AND ISOTOPES LA English DT Article DE Se-75; excitation functions AB The excitation functions for protons incident on Br-nat were measured from threshold up to 100 MeV by means of the stacked-foil technique. Where applicable, the measured cross-section values are compared with previously published values. Theoretical cross-sections were also calculated by means of the computer code ALICE (IPPE) for comparison purposes. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 IThemba Lab Accelerator Based Sci, ZA-7129 Somerset W, South Africa. Los Alamos Natl Lab, C INC Isotopes & Nucl Chem Grp, Los Alamos, NM 87545 USA. Univ Stellenbosch, Dept Phys, ZA-7602 Matieland, South Africa. RP de Villiers, D (reprint author), IThemba Lab Accelerator Based Sci, POB 722, ZA-7129 Somerset W, South Africa. NR 12 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD DEC PY 2002 VL 57 IS 6 BP 907 EP 913 AR PII S0969-8043(02)00234-8 DI 10.1016/S0969-8043(02)00234-8 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 631AV UT WOS:000180145200023 PM 12406636 ER PT J AU Rice, SF Hanush, RG AF Rice, SF Hanush, RG TI Absorptivity of carbon dioxide and molecular oxygen at 193 nm at high temperatures up to 1600 degrees C SO APPLIED SPECTROSCOPY LA English DT Article DE UV absorptivity; carbon dioxide; oxygen; high temperature; ArF laser absorption ID PHOTOFRAGMENT FLUORESCENCE; ELEVATED-TEMPERATURES; NACL; O-2; CO2; O2; PHOTODISSOCIATION; COEFFICIENTS; SIMULATION; PHOTOLYSIS AB The absorptivity of CO2 and O-2 at 193 nm over the temperature range of 900-1600 degreesC is reported. The data were collected in a flow-type tube furnace using an ArF excimer laser at the light source. CO2 was mixed at 5% by volume in N-2 and O-2 was examined at 5% and 10%. The internal transmittance of a 1-meter externally heated absorption cell was measured. The results establish a value for the absorptivity, alpha, for CO2 ranging as high as 2.35 X 10(-19) cm(2)/ molecule at 1600 degreesC. For O-2, the absorptivity is 1.81 X 10(-19) cm(2)/ molecule at 1600 degreesC. The results partially agree with those reported in the literature recently by others at 1000 degreesC and 193 nm and extend those data to higher temperatures; however, the agreement is far from exact. The results are inconsistent with the higher temperature, 1500-2500 degreesC, values inferred by others from indirect measurements for these two species. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Rice, SF (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. NR 22 TC 1 Z9 1 U1 1 U2 4 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD DEC PY 2002 VL 56 IS 12 BP 1621 EP 1625 DI 10.1366/000370202321116110 PG 5 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 628TB UT WOS:000180011700018 ER PT J AU Lacy, M Gates, EL Ridgway, SE de Vries, W Canalizo, G Lloyd, JP Graham, JR AF Lacy, M Gates, EL Ridgway, SE de Vries, W Canalizo, G Lloyd, JP Graham, JR TI Observations of quasar hosts with adaptive optics at Lick Observatory SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : evolution; methods : observational; quasars : individual (SDSS J005008.48+011330.4, SDSS J172732.39+584634.4, SDSS J232351.60+004034.4 ID RADIO-QUIET QUASARS; GALAXIES; EVOLUTION; TELESCOPE; SYSTEM; IMAGES; CAMERA; LOUD AB We present near-infrared H-band observations of the hosts of three z similar to 1 quasars from the Sloan Digital Sky Survey made with the adaptive optics system at Lick Observatory. We derive a point-spread function (PSF) for each quasar and model the host plus quasar nucleus to obtain magnitudes and approximate scale sizes for the host galaxies. We find our recovered host galaxies are similar to those found for z similar to 1 quasars observed with the Hubble Space Telescope. They also have, with one interesting exception, black hole mass estimates from their bulge luminosities that are consistent with those from emission-line widths. We thus demonstrate that adaptive optics can be successfully used for the quantitative study of quasar host galaxies, with the caveat that better PSF calibration will be needed for studies of the hosts of significantly brighter or higher redshift quasars with the Lick system. C1 CALTECH, SIRTF Sci Ctr, Pasadena, CA 91125 USA. Lawrence Livermore Natl Lab, IGPP, Livermore, CA 94550 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Santa Cruz, Lick Observ, Mt Hamilton, CA 95140 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Lacy, M (reprint author), CALTECH, SIRTF Sci Ctr, Mail Stop 220-6,1200 E Calif Blvd, Pasadena, CA 91125 USA. NR 28 TC 14 Z9 14 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 2002 VL 124 IS 6 BP 3023 EP 3030 DI 10.1086/344602 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 617KW UT WOS:000179361700001 ER PT J AU Bartelmann, M Perrotta, F Baccigalupi, C AF Bartelmann, M Perrotta, F Baccigalupi, C TI Halo concentrations and weak-lensing number counts in dark energy cosmologies SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE cosmology : theory; dense matter; gravitational lensing ID LARGE-SCALE STRUCTURE; POWER SPECTRUM; MATTER; QUINTESSENCE; CLUSTERS; GALAXIES; UNIVERSE; STATISTICS; SUPERNOVAE; CONSTANT AB We study the effects of a dark energy component with equation of state p = wrho with constant w greater than or equal to -1 on the formation of Cold Dark Matter (CDM) haloes. We find two main effects: first, haloes form earlier as w increases, and second, the amplitude of the dark-matter power spectrum gets reduced in order to remain compatible with the large scale Cosmic Microwave Background (CMB) anisotropies. These effects counteract. Using recipes derived from numerical simulations, we show that haloes are expected to be up to similar to50% more concentrated in CDM models with quintessence compared to LambdaCDM models, the maximum increase being reached for w similar to -0.6. For larger w, the amplitude of the power spectrum decreases rapidly and makes expected halo concentrations decrease. Halo detections through weak gravitational lensing are highly sensitive to halo concentrations. We show that weak-lensing halo counts with the aperture-mass technique increase by a factor of similar to2 as w is increased from -1 to - 0.6, offering a new method for constraining the nature of dark energy. C1 Max Planck Inst Astrophys, D-85741 Garching, Germany. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Osserv Astron Padova, I-35122 Padua, Italy. SISSA, ISAS, I-34014 Trieste, Italy. RP Bartelmann, M (reprint author), Max Planck Inst Astrophys, POB 1317, D-85741 Garching, Germany. RI Bartelmann, Matthias/A-5336-2014 NR 56 TC 41 Z9 41 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD DEC PY 2002 VL 396 IS 1 BP 21 EP 30 DI 10.1051/0004-6361:20021417 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 617YB UT WOS:000179387600003 ER PT J AU Mesa, D Baccigalupi, C De Zotti, G Gregorini, L Mack, KH Vigotti, M Klein, U AF Mesa, D Baccigalupi, C De Zotti, G Gregorini, L Mack, KH Vigotti, M Klein, U TI Polarization properties of extragalactic radio sources and their contribution to microwave polarization fluctuations SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE radio continuum : galaxies; polarization; cosmic microwave background ID SOURCE COUNTS; STATISTICAL-METHODS; ASTRONOMICAL DATA; UPPER LIMITS; SKY SURVEY; ANISOTROPIES; CENTIMETER; GALAXIES; SPECTRUM; GHZ AB We investigate the statistical properties of the polarized emission of extragalactic radio sources and estimate their contribution to the power spectrum of polarization fluctuations in the microwave region. The basic ingredients of our analysis are the NVSS polarization data, the multifrequency study of polarization properties of the B3-VLA sample (Mack et al. 2002) which has allowed us to quantify Faraday depolarization effects, and the 15 GHz survey by Taylor et al. (2001), which has provided strong constraints on the high-frequency spectral indices of sources. The polarization degree of both steep-and flat-spectrum sources at 1.4 GHz is found to be anti-correlated with the flux density. The median polarization degree at 1.4 GHz of both steep- and flat-spectrum sources brighter than S (1.4GHz) = 80 mJy is similar or equal to2.2%. The data by Mack et al. (2002) indicate a substantial mean Faraday depolarization at 1.4 GHz for steep spectrum sources, while the depolarization is undetermined for most flat/inverted-spectrum sources. Exploiting this complex of information we have estimated the power spectrum of polarization fluctuations due to extragalactic radio sources at microwave frequencies. We confirm that extragalactic sources are expected to be the main contaminant of Cosmic Microwave Background (CMB) polarization maps on small angular scales. At frequencies <30 GHz the amplitude of their power spectrum is expected to be comparable to that of the E-mode of the CMB. At higher frequencies, however, the CMB dominates. C1 Osserv Astron Padova, INAF, I-35122 Padua, Italy. Univ Padua, Dipartimento Astron, I-35122 Padua, Italy. SISSA, Int Sch Adv Studies, I-34014 Trieste, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. CNR, IRA, I-40129 Bologna, Italy. Univ Bologna, Dipartmento Fis, I-40126 Bologna, Italy. Univ Bonn, Inst Radioastron, D-53121 Bonn, Germany. Netherlands Fdn Res Astron, ASTRON, NL-7990 AA Dwingeloo, Netherlands. RP De Zotti, G (reprint author), Osserv Astron Padova, INAF, Vicolo Osservatorio 5, I-35122 Padua, Italy. NR 45 TC 43 Z9 43 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD DEC PY 2002 VL 396 IS 2 BP 463 EP 471 DI 10.1051/0004-6361:20021392 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 621DY UT WOS:000179574300013 ER PT J AU Mason, KO McHardy, IM Page, MJ Uttley, P Cordova, FA Maraschi, L Priedhorsky, WC Puchnarewicz, EM Sasseen, T AF Mason, KO McHardy, IM Page, MJ Uttley, P Cordova, FA Maraschi, L Priedhorsky, WC Puchnarewicz, EM Sasseen, T TI XMM-Newton observations of a possible light echo in the Seyfert 1 nucleus of NGC 4051 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (NGC 4051); galaxies : Seyfert; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; X-RAY; GALAXY ARAKELIAN-564; NGC 4051; VARIABILITY; ULTRAVIOLET; EMISSION; CONTINUUM AB We discuss a 1.5 day long observation of the bright variable Seyfert 1 galaxy NGC 4051 that was obtained with the X-ray and ultraviolet telescopes on XMM-Newton and extended in the X-ray band using the Rossi X-Ray Timing Explorer. The ultraviolet (2900 Angstrom) and X-ray (2-10 keV) light curves varied with peak-to-peak amplitudes of 5% and a factor of similar to4, respectively. A simple interband cross-correlation function shows three broad features: a positive correlation with coefficient at a lag r(M) = +0.63 at a lag (T(opt) - T(X-ray)) tau similar to +0.2 days, an anticorrelation with r(M) = -0.65 at tau similar to +0.7 days, and a broad but slightly weaker feature with r(M) greater than or equal to 0.53 over tau = 1.2-1.4 days. Because of the asymmetric sampling of the optical and X-ray data, only positive lags could be probed. Monte Carlo simulations based on synthetic uncorrelated light curves derived from the power spectrum of the real data give an similar to 85% confidence in features at this level. If the X-ray and UV light curves are indeed correlated, the lag is highly significant (i.e., not consistent with zero), which is suggestive of a scenario in which X-rays are being reprocessed into UV light at a distance from the X-ray source. A simple model in which the reprocessor is an inclined optically thick ring at a radius of 0.14 lt-days from the X-ray source reproduces the UV data well. A comparison of the modulated fractions in the ultraviolet and X-ray bands suggests that 5% of the 2900 Angstrom flux is produced in this way. The reprocessing site is close enough to the X-ray emitter for X-ray heating from a source with the luminosity of NGC 4051 to produce a brightening in the UV band, and the amount of UV flux emitted suggests that the covering fraction of the reprocessor is about 6%. We briefly discuss the possible physical nature of the reprocessing ring structure. C1 UCL, Mullard Space Sci Lab, Dept Space & Climate Phys, Dorking RH5 6NT, Surrey, England. Univ Southampton, Southampton SO17 1BJ, Hants, England. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Osservatorio Brera, I-20121 Milan, Italy. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mason, KO (reprint author), UCL, Mullard Space Sci Lab, Dept Space & Climate Phys, Holmbury St Mary, Dorking RH5 6NT, Surrey, England. EM kom@mssl.ucl.ac.uk OI Priedhorsky, William/0000-0003-0295-9138 NR 18 TC 22 Z9 22 U1 0 U2 1 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 DEC 1 PY 2002 VL 580 IS 2 BP L117 EP L120 DI 10.1086/345733 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 619DL UT WOS:000179458700006 ER PT J AU Zhang, WJ Stocker, R McCall, MR Forte, TM Frei, B AF Zhang, WJ Stocker, R McCall, MR Forte, TM Frei, B TI Lack of inhibitory effect of HDL on TNF alpha-induced adhesion molecule expression in human aortic endothelial cells SO ATHEROSCLEROSIS LA English DT Article DE high density lipoprotein; reconstituted high density lipoprotein; adhesion molecules; endothelial cells; atherosclerosis ID HIGH-DENSITY-LIPOPROTEINS; APOLIPOPROTEIN-A-I; CYTOKINE-INDUCED EXPRESSION; REVERSE CHOLESTEROL TRANSPORT; CORONARY HEART-DISEASE; E-SELECTIN; ATHEROSCLEROTIC LESIONS; VCAM-1 EXPRESSION; GENE-TRANSFER; MICE AB Monocyte adhesion to and transmigration across the endothelium are initiating steps in atherogenesis. Cytokine-induced adhesion molecule expression in human umbilical vein endothelial cells (HUVEC) has been reported to be inhibited by either native HDL or reconstituted discoidal HDL (rHDL). In the present study we investigated these putative anti-atherosclerotic effects of HDL and rHDL in a more physiologically relevant cell type, i.e. human aortic endothelial cells (HAEC). HDL isolated by ultracentrifugation from eleven healthy subjects or rHDL made with apoA-I and either 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (PLPC), or 1,2-dimyristoyl-sn-glycero-3-phosphocholine was incubated for 16 h with HAEC prior to stimulation with tumor necrosis factor-alpha (TNFalpha, 100 U/ml). Expression of E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) was measured by cell ELISA and Northern blot analysis. HDL (0.25, 0.5, 1.0 and 2.0 mg protein/ml) failed to significantly inhibit TNFalpha-induced mRNA and protein expression of all three adhesion molecules. Furthermore, of the three rHDL preparations (16 mumol/l apoA-I) only that containing the polyunsaturated PLPC significantly reduced TNFa-induced VCAM-I expression (by 29.9+/-9.1%). These data contrast with previously reported results using plasma HDL and HUVEC, and show that human HDL and rHDL, except for PLPC-rHDL, are ineffective inhibitors of TNFalpha-induced adhesion molecule expression in HAEC. The ability of polyunsaturated phospholipids in HDL to affect endothelial activation remains to be further investigated. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. C1 Oregon State Univ, Linus Pauling Inst, Corvallis, OR 97331 USA. Univ New S Wales, Fac Med, Sch Med Sci, Ctr Thrombosis & Vasc Res, Sydney, NSW 2052, Australia. Lawrence Berkeley Natl Lab, Div Life Sci, Dept Mol & Nucl Med, Berkeley, CA 94720 USA. RP Frei, B (reprint author), Oregon State Univ, Linus Pauling Inst, 571 Weniger Hall, Corvallis, OR 97331 USA. FU NHLBI NIH HHS [HL-18574, HL-60886]; NIEHS NIH HHS [ES11542] NR 47 TC 11 Z9 13 U1 0 U2 3 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0021-9150 J9 ATHEROSCLEROSIS JI Atherosclerosis PD DEC PY 2002 VL 165 IS 2 BP 241 EP 249 AR PII S0021-9150(02)00247-2 DI 10.1016/S0021-9150(02)00247-2 PG 9 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 617FR UT WOS:000179351700007 PM 12417274 ER PT J AU Cheng, MD Tanner, RL AF Cheng, MD Tanner, RL TI Characterization of ultrafine and fine particles at a site near the Great Smoky Mountains National Park SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE the Great Smoky Mountains National Park; factor analysis; ultrafine and fine particles; source-receptor relationships ID AEROSOL-SIZE DISTRIBUTIONS; EVENTS AB Continuous measurements were taken during a 22-day campaign held in the summer of 2000 at a site close to the Great Smoky Mountains National Park in eastern Tennessee. The campaign was conducted to investigate the relationships between ultrafine/fine particles and gaseous species observed. A varimax-rotation factor analysis was performed to explore the relationship of the fine and ultrafine particle number concentrations, the gaseous species concentration, the mean wind speed, and the solar radiation. A 6-factor model was found to best resolve 79.7% of the variability embedded in the data. The model suggests that 31.4% of the data variability could be explained by ultrafine particles (the diameters smaller than. or equal to 100 nm). It was difficult to label this factor without chemistry information of the ultrafine particles. However, no gas species were loaded on Factor I indicating the ultrafine particles observed in this study were not associated with primary source emissions. The decoupling of the ultrafine particles from the fine particles also implies that the former ones might have been produced and transported to the site by separated mechanisms, from those of fine particles. The second factor included the PM2.5 mass concentration and the number concentrations of particles in the diameter range of 101-400 mn. The loading pattern on Factor 2 led to the conclusion that this factor was contributed by regional transport. The third factor includes CO, NO2, reactive odd nitrogen (NOy), and SO2 that were contributed by primary source emissions. The mean wind speed and ozone were loaded in Factor 4 that was labeled as ozo. ne transport. Identification of this factor led to an observation that ozone transport to the site was essentially decoupled from the regional transport factor of fine particles (i.e., Factor 2). Solar radiation was singly included in the fifth factor indicating this is a unique factor. The quality of NO data was marginal and the variable was distilled by the model into Factor 6. A multiple regression analysis further indicated that PM2.5 mass concentration was best explained by CO, 03, and number concentrations of particles in the diameter range between 0.1 and 0.4 mum. We also identified two unique events during the campaign in which the number concentrations of 31-51 nm particles dramatically increased by a factor of 10 in 30min, reaching 40,000 cm(-3) and lasting for a couple of hours. Particles in the size range just below and above those in the 31-51 nm diameter range also exhibited increases during these events, but the changes were much less dramatic. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Natl Fertilizer & Environm Res Ctr, Tennessee Valley Author, Muscle Shoals, AL 35662 USA. RP Cheng, MD (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,Bldg 1505,Mail Stop 6038, Oak Ridge, TN 37831 USA. RI Cheng, Meng-Dawn/C-1098-2012; OI Cheng, Meng-Dawn/0000-0003-1407-9576 NR 17 TC 12 Z9 12 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD DEC PY 2002 VL 36 IS 38 BP 5795 EP 5806 AR PII S1352-2310(02)00625-8 DI 10.1016/S1352-2310(02)00625-8 PG 12 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 620UH UT WOS:000179550500005 ER PT J AU Xu, YW Wesely, ML Pierce, TE AF Xu, YW Wesely, ML Pierce, TE TI Estimates of biogenic emissions using satellite observations and influence of isoprene emission on O-3 formation over the eastern United States SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE biogenic emissions; remote sensing; isoprene; ozone; modeling ID ATMOSPHERIC BOUNDARY-LAYER; NITRIC-OXIDE EMISSIONS; GASEOUS DRY DEPOSITION; REGIONAL SCALES; MODEL; HYDROCARBONS; CHEMISTRY; FOREST; FLUXES; SOILS AB A biogenic emissions model for isoprene, monoterpenes, and nitric oxide has been developed with algorithms that rely on normalized difference vegetative index values derived from satellite remote sensing data to infer leaf area index. The model obtains emission factors from the Biogenic Emission Inventory System (BEIS). This biogenic emissions model, combined with a dry deposition model, was applied with environmental variable values supplied by MM5 (the fifth-generation Mesoscale Model). The modeled temporal variations and spatial distributions of the surface emissions rates of isoprene, monoterpenes, and nitric oxide the eastern US agreed well with reported simulations, measurements, and inferences. Use of the satellite data generates considerable detail in the spatial patterns, high temporal resolution, and a smooth seasonal variation in the emission rates. The new biogenic emissions model was used with a photochemistry modeling system to infer ozone (03) concentrations in the lower troposphere above the eastern United States for a two-day case in July 1995, which had 03 episodes studied previously by the Ozone Transport Assessment Group. Compared to the results from the OTAG application of BEIS2, the satellite-data-derived isoprene emissions were slightly lower in the northeastern United States, which resulted in smaller values Of O-3 concentration and were 3-4 times higher in southeastern mixed forests; which had little impact on O-3 except near strong NOx emission sources. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NOAA, Air Resources Lab, Res Triangle Pk, NC 27711 USA. RP Wesely, ML (reprint author), Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NR 33 TC 10 Z9 11 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD DEC PY 2002 VL 36 IS 38 BP 5819 EP 5829 AR PII S1352-2310(02)00357-6 DI 10.1016/S1352-2310(02)00357-6 PG 11 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 620UH UT WOS:000179550500007 ER PT J AU Ozaki, T Ambe, S Abe, T Francis, AJ AF Ozaki, T Ambe, S Abe, T Francis, AJ TI Adsorption of radionuclides on silica and their uptake by rice plants from silica-multitracer solutions - The effects of pH SO BIOLOGICAL TRACE ELEMENT RESEARCH LA English DT Article DE pH effect; radionuclide; rice plant; silica; uptake ID SOIL; CESIUM; WHEAT; ROOTS; IONS; RB AB We investigated the effect of solution pH on the adsorption on silica of a mixture radionuclides Rb-83, Sr-85, Mn-54, Zn-65, Y-88, and Se-75 generated from irradiation of Ag in a 135-MeV/nucleon C-12 beam accelerated by the RIKEN Ring Cyclotron and (CS)-C-137 obtained commercially. Then, we related these findings to their uptake by a rice plant (Oryza sativa L. cv. Koshihikari) from a silica-multitracer solution at pH 4.3 +/- 0.2 and at 5.3 +/- 0.2. To evaluate both adsorption and uptake, precisely we used a multitracer technique that simultaneously tracked the movements of all of the radionuclides. There was an increase in the uptake of Rb, Cs, Sr, Mn, and Zn by the rice plants with the increase in pH from 4.3 to 5.3. By contrast, the uptake of Y and Se was less at the higher pH. Our findings suggest that the uptake of these elements is governed by their transport systems on the plasma membrane and by their affinity to silica, both of which are regulated by H+ concentration. C1 Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ozaki, T (reprint author), Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. NR 26 TC 3 Z9 3 U1 0 U2 5 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0163-4984 J9 BIOL TRACE ELEM RES JI Biol. Trace Elem. Res. PD WIN PY 2002 VL 90 IS 1-3 BP 273 EP 281 DI 10.1385/BTER:90:1-3:273 PG 9 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA 635RT UT WOS:000180413500022 PM 12666841 ER PT J AU Krulevitch, P Bennett, W Hamilton, J Maghribi, M Rose, K AF Krulevitch, P Bennett, W Hamilton, J Maghribi, M Rose, K TI Polymer-based packaging platform for hybrid microfluidic systems SO BIOMEDICAL MICRODEVICES LA English DT Article DE packaging; microfluidic systems; polydimethylsiloxane (PDMS); hybrid integration; polymer molding AB A polymer-based packaging platform for creating hybrid microfluidic systems is presented. Polydimethylsiloxane (PDMS) is cast into an acrylic mold frame with suspended elements that are removed after curing to form chip cavities, inlet and outlet ports, microchannels, and reservoirs. The packaging approach enables the integration of off-the-shelf components such as pumps and valves with glass microfluidic devices, electronic chips, sample reservoirs, and flow channels. A particle pre-concentration module with a glass capture chip and integrated micropump is shown as an example. A pneumatically driven microfluidic pumping module is also shown. Custom microfluidic interconnects for interfacing to micro-scale fluidic systems are presented. The connectors are capable of withstanding more than 1000 psi and allow microdevices to be rapidly connected to macroscopic devices and systems, without the use of tools. C1 Lawrence Livermore Natl Lab, Ctr Micro Technol, Livermore, CA 94551 USA. RP Krulevitch, P (reprint author), Lawrence Livermore Natl Lab, Ctr Micro Technol, POB 808, Livermore, CA 94551 USA. NR 20 TC 33 Z9 35 U1 0 U2 7 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1387-2176 J9 BIOMED MICRODEVICES JI Biomed. Microdevices PD DEC PY 2002 VL 4 IS 4 BP 301 EP 308 DI 10.1023/A:1020958323891 PG 8 WC Engineering, Biomedical; Nanoscience & Nanotechnology SC Engineering; Science & Technology - Other Topics GA 610HT UT WOS:000178955200006 ER PT J AU Muller, HG Su, CL Dueker, SR Lin, YM Clifford, A Buchholz, BA Vogel, JS AF Muller, HG Su, CL Dueker, SR Lin, YM Clifford, A Buchholz, BA Vogel, JS TI Semiparametric modeling of labeled-cell kinetics, with application to isotope labeling of erythrocytes SO BIOMETRICS LA English DT Article DE cell survival; labeled-cell fraction; smoothing ID FOLIC-ACID; DYNAMICS AB We propose a stochastic model for the kinetics of cells that have been tagged with a chemical label. The proposed model consists of two components: a parametrically specified distribution for the time to incorporation of the label into the cells and a nonparametric survival function reflecting the survival time of the label-cell combination. The target quantity of this modeling approach is the fraction of labeled cells among all cells, viewed as a function of time. Longitudinal measurements of this labeled-cell fraction are available from a recent experiment with folate-labeled red blood cells. The proposed semiparametric model is fitted to these data and some of the implications are explored. The proposed method also includes bootstrap-based inference. C1 Univ Calif Davis, Dept Stat, Davis, CA 95616 USA. Univ Calif Davis, Dept Nutr, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. RP Muller, HG (reprint author), Univ Calif Davis, Dept Stat, 1 Shields Ave, Davis, CA 95616 USA. RI Buchholz, Bruce/G-1356-2011 FU NIDDK NIH HHS [R01 DK45939] NR 21 TC 1 Z9 1 U1 0 U2 2 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0006-341X J9 BIOMETRICS JI Biometrics PD DEC PY 2002 VL 58 IS 4 BP 937 EP 945 DI 10.1111/j.0006-341X.2002.00937.x PG 9 WC Biology; Mathematical & Computational Biology; Statistics & Probability SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology; Mathematics GA 620NL UT WOS:000179539400025 PM 12495148 ER PT J AU Lavoie, H Blaudez, D Vaknin, D Desbat, B Ocko, BM Salesse, C AF Lavoie, H Blaudez, D Vaknin, D Desbat, B Ocko, BM Salesse, C TI eSpectroscopic and structural properties of valine gramicidin A in monolayers at the air-water interface SO BIOPHYSICAL JOURNAL LA English DT Article ID TRANSFORM INFRARED-SPECTROSCOPY; X-RAY-DIFFRACTION; AIR/WATER INTERFACE; SECONDARY STRUCTURE; MEMBRANE-PROTEINS; IR SPECTROSCOPY; PHOTOSYSTEM-II; ION MOVEMENTS; IN-SITU; REFLECTION AB Monomolecular films of valine gramicidin A (VGA) were investigated in situ at the air-water interface by x-ray reflectivity and x-ray grazing incidence diffraction as well as polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS). These techniques were combined to obtain information on the secondary structure and the orientation of VGA and to characterize the shoulder observed in its pi-A isotherm. The thickness of the film was obtained by x-ray reflectivity, and the secondary structure of VGA was monitored using the frequency position of the amide I band. The PM-IRRAS spectra were compared with the simulated ones to identify the conformation adopted by VGA in monolayer. At large molecular area, VGA shows a disordered secondary structure, whereas at smaller molecular areas, VGA adopts an anti-parallel double-strand intertwined beta(5.6) helical conformation with 30degrees orientation with respect to the normal with a thickness of 25 Angstrom. The interface between bulk water and the VGA monolayer was investigated by x-ray reflectivity as well as by comparing the experimental and the simulated PM-IRRAS spectra on D2O and H2O, which suggested the presence of oriented water molecules between the bulk and the monolayer. C1 Univ Quebec, Dept Chim Biol, Trois Rivieres, PQ G9A 5H7, Canada. Univ Bordeaux 1, Ctr Phys Mol Opt & Hertzienne, F-33405 Talence, France. Univ Bordeaux 1, Lab Physicochim Mol, F-33405 Talence, France. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Salesse, C (reprint author), Univ Quebec, Dept Chim Biol, Trois Rivieres, PQ G9A 5H7, Canada. RI Vaknin, David/B-3302-2009 OI Vaknin, David/0000-0002-0899-9248 NR 47 TC 23 Z9 23 U1 0 U2 1 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD DEC PY 2002 VL 83 IS 6 BP 3558 EP 3569 PG 12 WC Biophysics SC Biophysics GA 633AD UT WOS:000180256300059 PM 12496123 ER PT J AU Rahman, KSM Thahira-Rahman, J Lakshmanaperumalsamy, P Banat, IM AF Rahman, KSM Thahira-Rahman, J Lakshmanaperumalsamy, P Banat, IM TI Towards efficient crude oil degradation by a mixed bacterial consortium SO BIORESOURCE TECHNOLOGY LA English DT Article DE biodegradation; crude oil; mixed bacterial consortium; optimum conditions ID CONTAMINATED SOIL; BIODEGRADATION; BIOREMEDIATION; HYDROCARBONS; PETROLEUM; REMEDIATION AB A laboratory study was undertaken to assess the optimal conditions for biodegradation of Bombay High (BH) crude oil. Among 130 oil degrading bacterial cultures isolated from oil contaminated soil samples, Micrococcus sp. GS2-22, Corynebacterium sp. GS5-66, Flavobacterium sp. DS5-73, Bacillus sp. DS6-86 and Pseudomonas sp. DS10-129 were selected for the study based on the efficiency of crude oil utilisation. A mixed bacterial consortium prepared using the above strains was also used. Individual bacterial cultures showed less growth and degradation than did the mixed bacterial consortium. At 1% crude oil concentration, the mixed bacterial consortium degraded a maximum of 78% of BH crude oil. This was followed by 66% by Pseudomonas sp. DS10-129, 59% by Bacillus sp. DS6-86, 49% by Micrococcus sp. GS2-22, 43% by Corynebacterium sp. GS5-66 and 41% by Flavobacterium sp. DS5-73. The percentage of degradation by the mixed bacterial consortium decreased from 78% to 52% as the concentration of crude oil was increased from 1% to 10%. Temperature of 30 degreesC and pH 7.5 were found to be optima for maximum biodegradation. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 Univ Ulster, Sch Biol & Environm Studies, Biotechnol Res Grp, Coleraine BT52 1SA, Londonderry, North Ireland. Bharathiar Univ, Dept Environm Sci, Coimbatore 641046, Tamil Nadu, India. RP Rahman, KSM (reprint author), Brookhaven Natl Lab, Energy Sci & Technol Dept, Bldg 815, Upton, NY 11973 USA. RI Banat, Ibrahim/C-1910-2013; OI Banat, Ibrahim/0000-0001-8964-2840; Rahman, Pattanathu/0000-0001-7416-4372 NR 20 TC 128 Z9 152 U1 3 U2 34 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0960-8524 J9 BIORESOURCE TECHNOL JI Bioresour. Technol. PD DEC PY 2002 VL 85 IS 3 BP 257 EP 261 AR PII S0960-8524(02)00119-0 DI 10.1016/S0960-8524(02)00119-0 PG 5 WC Agricultural Engineering; Biotechnology & Applied Microbiology; Energy & Fuels SC Agriculture; Biotechnology & Applied Microbiology; Energy & Fuels GA 594QZ UT WOS:000178063400007 PM 12365493 ER PT J AU Yoon, JR Laible, PD Gu, M Scott, HN Collart, FR AF Yoon, JR Laible, PD Gu, M Scott, HN Collart, FR TI Express primer tool for high-throughput gene cloning and expression SO BIOTECHNIQUES LA English DT Article ID DESIGN; DNA; SEQUENCE; GENOME AB High-throughput approaches for gene cloning and expression require the development of new nonstandard tools for molecular biologists and biochemists. We introduce a Web-based tool to design primers. specifically for the generation of expression clones for both laboratory-scale and high-throughput projects. The application is designed not only to allow the user complete flexibility to specify primer design parameters but also to minimize the amount Of manual intervention needed to generate a large number of primers for the simultaneous amplification of multiple target genes. C1 Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP Collart, FR (reprint author), Argonne Natl Lab, Biosci Div, Bldg 202, Argonne, IL 60439 USA. OI Collart, Frank/0000-0001-6942-4483 FU NIGMS NIH HHS [GM62414-01] NR 15 TC 17 Z9 21 U1 0 U2 1 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD DEC PY 2002 VL 33 IS 6 BP 1328 EP + PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 628LL UT WOS:000179996500025 PM 12503320 ER PT J AU Zhang, JJ Lay, T Zaslow, J Walter, WR AF Zhang, JJ Lay, T Zaslow, J Walter, WR TI Source effects on regional seismic discriminant measurements SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID WESTERN UNITED-STATES; LATERAL VELOCITY VARIATIONS; LITTLE-SKULL-MOUNTAIN; WAVE-GUIDE INFLUENCES; SOUTHERN-CALIFORNIA; NTS EXPLOSIONS; STATISTICAL-ANALYSIS; NUCLEAR-EXPLOSIONS; CENTRAL-ASIA; EARTHQUAKES AB Source effects on high-frequency regional seismic discriminant measurements involving P/S-type ratios (Pn/Lg, Pg/Lg) are isolated for earthquakes in southern California and southern Nevada. The scatter in earthquake population discriminant measurements for fixed propagation paths is statistically analyzed to assess the spatial and frequency-dependent contributions from source radiation pattern and source depth variations along with variable near-source scattering. This is useful because procedures for reducing the variance caused by propagation effects must be constrained by knowledge of the intrinsic scatter resulting from independent source effects, for which corrections are not available without a priori knowledge of the source type and depth. Broadband waveforms for earthquakes near the Nevada Test Site (NTS) and in southern California recorded at stations of the Livermore NTS Network (LNN), the Caltech TERRAscope Network, and the Berkeley Digital Seismic Network (BDSN) are used to obtain Pg/Lg and Pn/Lg measurements and to assess source depth and mechanism contributions to measurement variance. Pn/Lg and Pg/Lg spectral amplitude ratios for several frequency bands between 0.5 and 10 Hz from vertical velocity waveforms are computed for a total of 18 tightly located clusters of earthquakes. For each cluster, we examine the correlations between observed Pn/Lg and Pg/Lg ratios and estimated source depths or predictions based on previously determined source mechanisms. Focal mechanism predictions do not match the observations well, likely due to strong near-source scattering and directivity effects that overwhelm the point-source radiation pattern. However, the data do show significant scatter even for sources only a few kilometers apart. Source depth produces some coherent trends, which can be emphasized by averaging results from multiple stations. These trends vary from region to region, presumably due to specific local crustal layering, but most of the variance is not deterministically predictable and appears to arise from strong variations in near-source scattering. Variance estimates for logarithmic amplitude ratios normalized by mean amplitude ratios vary from 0.01 to 0.05 for different phase pairs. Frequency-dependent variations of the mean, variance, minimum, and maximum amplitude ratio parameters show strong distance dependence out to about 300 kin and then appear to become independent of event-station distance. These variance parameters appear to be suitable for use in spatial interpolations of observed P/S-type ratios for a specific unidentified event path, as needed for nuclear test monitoring. C1 Univ Calif Santa Cruz, Dept Earth Sci, IGPP Ctr Study Imaging & Dynam Earth, Santa Cruz, CA 95064 USA. Lawrence Livermore Natl Lab, Geophys & Global Secur Div, Livermore, CA 94550 USA. RP Zhang, JJ (reprint author), Univ Calif Santa Cruz, Dept Earth Sci, IGPP Ctr Study Imaging & Dynam Earth, Santa Cruz, CA 95064 USA. RI Walter, William/C-2351-2013 OI Walter, William/0000-0002-0331-0616 NR 35 TC 6 Z9 7 U1 1 U2 1 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD DEC PY 2002 VL 92 IS 8 BP 2926 EP 2945 DI 10.1785/0120010242 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 647AX UT WOS:000181070000004 ER PT J AU Yang, XN AF Yang, XN TI A numerical investigation of L-g geometrical spreading SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID UNITED-STATES EARTHQUAKES; SPECTRAL CHARACTERISTICS; NTS EXPLOSIONS; NEW-YORK; ATTENUATION; PROPAGATION; WAVES; DISCRIMINATION; TRANSPORTABILITY; EXCITATION C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Yang, XN (reprint author), Los Alamos Natl Lab, EES-11,MS D443, Los Alamos, NM 87545 USA. NR 34 TC 29 Z9 29 U1 0 U2 1 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD DEC PY 2002 VL 92 IS 8 BP 3067 EP 3079 DI 10.1785/0120020046 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 647AX UT WOS:000181070000012 ER PT J AU Sprenke, KF White, BG Rohay, AC Whyatt, JK Stickney, MC AF Sprenke, KF White, BG Rohay, AC Whyatt, JK Stickney, MC TI Comparison of body-wave displacement with damage observations of a Rockburst, Coeur d'Alene Mining District, Idaho SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID LUCKY-FRIDAY-MINE; INDUCED SEISMICITY; NORTHERN IDAHO; EVENTS AB Fault-plane solutions for seismic events in the deep underground mines of the Coeur d'Alene Mining District in northern Idaho have been difficult to reconcile with actual observations of mine damage. Examination of rockburst damage in stopes as well as measurements of slip movements on bedding planes suggests that rockbursts in the Lucky Friday Mine are closely associated with gradual bedding-plane slip. This progressive slip reduces the physical dimensions of stopes and increases compressive stress resulting in sudden implosive failure of the stope margins. Thus, much of the difficulty in evaluating seismological data arises from the implosional nature of these. rockbursts, making the first motion of the events difficult to interpret. In the summer of 1998, we acquired several months of high-quality seismic data from five stations in the vicinity of the Lucky Friday Mine. This is the first time that a network of high dynamic-range, three-component instruments has been deployed in this mining district. On 29 August, 1988 at 6:09 UTC, a M-L 2.9 event occurred at the Lucky Friday Mine. This event resulted from bedding-plane slip and caused extensive damage in the mine that was carefully documented. Using a leastsquares procedure, we were able to find a well-constrained moment tensor solution that matches the P and S displacement amplitudes measured at the five temporary stations. We derived a model of the mechanism to compare with the underground observations of bedding-plane slip and damage. We conclude that high-quality seismological instrumentation is required if meaningful results are to be obtained for understanding the source mechanisms of shear-implosional rockbursts. C1 Univ Idaho, Moscow, ID 83844 USA. Spokane Res Lab, Spokane, WA 99207 USA. Battelle Mem Inst, Pacific NW Div, Richland, WA 99352 USA. Montana Bur Mines & Geol, Earthquake Studies Off, Butte, MT 59701 USA. RP Sprenke, KF (reprint author), Univ Idaho, Moscow, ID 83844 USA. NR 20 TC 2 Z9 2 U1 2 U2 11 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD DEC PY 2002 VL 92 IS 8 BP 3321 EP 3328 DI 10.1785/0120010105 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 647AX UT WOS:000181070000030 ER PT J AU Wilson, D Leon, J Aster, R Ni, J Schlue, J Grand, S Semken, S Baldridge, S Gao, W AF Wilson, D Leon, J Aster, R Ni, J Schlue, J Grand, S Semken, S Baldridge, S Gao, W TI Broadband seismic background noise at temporary seismic stations observed on a regional scale in the southwestern United States SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID SITE CHARACTERISTICS AB Background noise power spectral density (PSD) estimates for 54 PASSCAL Colorado Plateau/Rio Grande Rift/Great Plains Seismic Transect (LA RISTRA) stations were computed using data from 1999 to 2000. At long periods (0.01-0.1 Hz), typical vertical noise levels are approximately 12 dB higher than the nearby Global Seismic Network (GSN) borehole station ANMO, but horizontal power spectral density (PSD)noise levels are approximately 30 dB higher. Long-period noise levels exhibit essentially no spatial correlation along the LA RISTRA transect, indicating that local thermal or atmosphere-driven local slab tilt is the dominant source of noise in this band. Between 0.1 and 0.3 Hz, typical noise levels are dominated by naturally occurring microseismic noise and are essentially identical to those observed at ANMO. At short periods, 0.3-8 Hz, typical noise levels along the network exceed ANMO levels by approximately 15 dB, with the highest levels corresponding to proximity to cultural noise sources. No significant day/night variations were observed in the microseismic band; however, both low- and high-frequency noise levels show an increase of up to 8 dB in median midday versus midnight noise levels. We find that the major shortcomings of these shallow PASSCAL-style temporary vaults relative to a GSN-style borehole installation are increased susceptibility to long-period horizontal ( greater than or equal to20 sec) noise and to surface noise sources above approximately 2 Hz. Although the high-frequency near-surface noise field is unavoidable in shallow vaults, we suggest that increased understanding and mitigation of local tilt effects in shallow vaults offers the possibility of significantly improving the long-period noise environment. C1 New Mexico Inst Min & Technol, Socorro, NM 87801 USA. New Mexico State Univ, Dept Phys, MSC3D, Las Cruces, NM 88003 USA. Univ Texas, Dept Geol Sci, Austin, TX 78712 USA. Dine Coll, Div Nat Sci, Shiprock, NM 87420 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Wilson, D (reprint author), New Mexico Inst Min & Technol, Socorro, NM 87801 USA. RI Grand, Stephen/B-4238-2011; Aster, Richard/E-5067-2013 OI Aster, Richard/0000-0002-0821-4906 NR 17 TC 42 Z9 42 U1 0 U2 2 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD DEC PY 2002 VL 92 IS 8 BP 3335 EP 3341 DI 10.1785/0120010234 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 647AX UT WOS:000181070000032 ER PT J AU Trabert, E AF Trabert, E TI Precise atomic lifetime measurements with stored ion beams and ion traps SO CANADIAN JOURNAL OF PHYSICS LA English DT Review ID MAGNETIC DIPOLE TRANSITIONS; BORON ISOELECTRONIC SEQUENCE; METASTABLE LEVEL LIFETIMES; HIGHLY-CHARGED IONS; 3P P-2(3/2) LEVEL; 1S2S S-3(1) LEVEL; ART. NO. 062508; BE-LIKE IONS; STORAGE-RING; M1 TRANSITION AB For many years, atomic lifetime measurements on multiply-charged ions have been done almost exclusively by beam-foil spectroscopy. For low ion charges, however, spin-changing "intercombination" transitions have a rate that renders them too slow for traditional fast-beam techniques. Here ion traps and fast-ion beams have been combined in the concept of heavy-ion storage rings. These devices have permitted not only an extension of intercombination lifetime measurements down to singly charged ions, but they also facilitated similar measurements on electric-dipole forbidden transitions. The electron-beam ion trap (EBIT) complements the storage-ring work for work on highly charged ions. Achievements, technical issues, and prospects are outlined. C1 Ruhr Univ Bochum, D-44780 Bochum, Germany. Lawrence Livermore Natl Lab, Div Phys & Adv Technol, Livermore, CA 94550 USA. RP Trabert, E (reprint author), Ruhr Univ Bochum, D-44780 Bochum, Germany. EM traebert@ep3.ruhr-uni-bochum.de NR 113 TC 32 Z9 32 U1 0 U2 1 PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS PI OTTAWA PA 65 AURIGA DR, SUITE 203, OTTAWA, ON K2E 7W6, CANADA SN 0008-4204 EI 1208-6045 J9 CAN J PHYS JI Can. J. Phys. PD DEC PY 2002 VL 80 IS 12 BP 1481 EP 1501 DI 10.1139/P02-123 PG 21 WC Physics, Multidisciplinary SC Physics GA 663NK UT WOS:000182011500004 ER PT J AU Utter, SB Beiersdorfer, P Trabert, E AF Utter, SB Beiersdorfer, P Trabert, E TI Electron-beam ion-trap spectra of tungsten in the EUV SO CANADIAN JOURNAL OF PHYSICS LA English DT Article ID X-RAY-SPECTRA; ENERGY-LEVELS; RANGE; LINE; WAVELENGTHS; EMISSION; ANGSTROM; PLASMAS; REGION AB At the Livermore electron-beam ion-trap facility, extreme-ultraviolet spectra of tungsten have been recorded in the wavelength range 40-85 Angstrom. The electron-beam energy was varied systematically to identify the individual spectra of Rb-like W37+ to Cu-like W45+. About 60 spectral features have been identified. C1 Lawrence Livermore Natl Lab, Div Phys & Adv Technol, Livermore, CA 94550 USA. RP Trabert, E (reprint author), Lawrence Livermore Natl Lab, Div Phys & Adv Technol, Livermore, CA 94550 USA. NR 21 TC 76 Z9 76 U1 1 U2 3 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4204 J9 CAN J PHYS JI Can. J. Phys. PD DEC PY 2002 VL 80 IS 12 BP 1503 EP 1515 DI 10.1139/P02-132 PG 13 WC Physics, Multidisciplinary SC Physics GA 663NK UT WOS:000182011500005 ER PT J AU Lopez-Urrutia, JR Beiersdorfer, P Widmann, K Decaux, V AF Lopez-Urrutia, JR Beiersdorfer, P Widmann, K Decaux, V TI Visible spectrum of highly charged ions: The forbidden optical lines of Kr, Xe, and Ba ions in the Ar I to Kr I isoelectronic sequence SO CANADIAN JOURNAL OF PHYSICS LA English DT Article ID M1 TRANSITION; GROUND-STATE; TRAP; LIFETIME; TOKAMAK; TEMPERATURE; PLASMAS; LEVEL AB We present experimental data on visible transitions in highly charged ions observed in the Lawrence Livermore National Laboratory (LLNL) electron beam ion traps, including results from lines within the ground-state configuration and the first excited configuration. Measurements of lines produced by Kr (q = 11+ to 22+), Xe (q = 18+ to 35+), and Ba (q = 28+ to 36+) ions, corresponding mainly to 3s(l) 3p(m) 3d(n) configurations, were carried out. The ionization stages were determined experimentally by sweeping the electron beam energy over the ionization threshold of each species. We propose possible identifications for the lines with the help of simple atomic structure calculations. However, most observed lines remained unidentified, demonstrating that the understanding of visible spectra from highly charged ions, even if obtained under nearly "ideal" experimental conditions, is still in its infancy. These spectral data may be useful for the diagnostics of magnetically confined plasmas and may set the stage for future measurements of radiative lifetimes. In our experiments, we used the emission from visible lines to image the intersection of the electron beam with a beam of neutral atoms injected into the trap at a right angle as well as the ion cloud in the trap. Under some conditions, the diameter of the ion cloud may be an order of magnitude larger than that of the electron beam. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Beiersdorfer, P (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. RI Crespo Lopez-Urrutia, Jose R./F-7069-2011 OI Crespo Lopez-Urrutia, Jose R./0000-0002-2937-8037 NR 36 TC 26 Z9 26 U1 0 U2 5 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4204 J9 CAN J PHYS JI Can. J. Phys. PD DEC PY 2002 VL 80 IS 12 BP 1687 EP 1700 DI 10.1139/P02-080 PG 14 WC Physics, Multidisciplinary SC Physics GA 663NK UT WOS:000182011500020 ER PT J AU Fayek, M Kyser, TK Riciputi, LR AF Fayek, M Kyser, TK Riciputi, LR TI U and Pb isotope analysis of uranium minerals by ion microprobe and the geochronology of the McArthur River and Sue Zone uranium deposits, Saskatchewan, Canada SO CANADIAN MINERALOGIST LA English DT Article DE uraninite; U-Pb; SIMS analyses; ages; geochronology; fluid-circulation events; Athabasca Basin; Saskatchewan ID PROTEROZOIC ATHABASCA BASIN; CIGAR LAKE DEPOSIT; NORTHERN SASKATCHEWAN; FLUID-FLOW; URANINITE; EVENTS; AGES; MINERALIZATION; IONIZATION; EVOLUTION AB A method for in situ U-Pb isotopic analyses by secondary ion mass spectrometry (SIMS) has been developed for uranium minerals with a range of chemical compositions. This method combines the advantages of conventional U-Pb dating (i.e., use of concordia) and in situ analysis, and therefore is ideally suited for the study of chemically complex and fine-grained uranium oxides associated with uranium deposits. An ion-yield normalizing coefficient (alphaSIMS) that accounts for variation in relative ion-yields with chemical composition of the mineral of interest was calculated using uraninite standards that cover a range of U and Ph compositions, and an appropriate empirical mass-bias model was developed. The coefficient aSIMS varies as a function of wt% PbO, requiring two working curves to define the relationship between the Pb-206(+)/U-218(+), and Pb-207(+)/U-231(+), values measured by SIMS versus the "true" (206)pb/U-238 and Pb-207/U-235 values: Pb-207(+)/U-235 = 0.762 +/- 0.015 (Pb-207(+)/U-235(+))(0.69 +/- 0.02) Pb-206/U-238 = 0.333 +/- 0.007 (Pb-206(+)/U-238(+))(0.64 +/- 0.02) The application of this technique to unconformity-type uranium deposits in the Athabasca Basin, Saskatchewan, demonstrates that at the microscale, these deposits preserve the initial age of mineralization (1486 to 1519 Ma) and a temporal record of accretion and breakup of supercontinents. Prior to in situ analyses, this detailed chronological record was obscured by the wide variability in U-Pb and Pb-Pb data obtained by micro-drilling and conventional isotopic analyses due to mixing of different generations of minerals. C1 Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Queens Univ, Dept Geol Sci, Kingston, ON K7L 3N6, Canada. RP Fayek, M (reprint author), Univ Tennessee, Dept Geol Sci, 306 Geol Bldg, Knoxville, TN 37996 USA. NR 49 TC 39 Z9 40 U1 1 U2 8 PU MINERALOGICAL ASSOC CANADA PI OTTAWA PA PO BOX 78087, MERILINE POSTAL OUTLET, 1460 MERIVALE RD, OTTAWA, ONTARIO K2E 1B1, CANADA SN 0008-4476 J9 CAN MINERAL JI Can. Mineral. PD DEC PY 2002 VL 40 BP 1553 EP 1569 DI 10.2113/gscanmin.40.6.1553 PN 6 PG 17 WC Mineralogy SC Mineralogy GA 640XT UT WOS:000180714600001 ER PT J AU Muschler, J Levy, D Boudreau, R Henry, M Campbell, K Bissell, MJ AF Muschler, J Levy, D Boudreau, R Henry, M Campbell, K Bissell, MJ TI A role for dystroglycan in epithelial polarization: Loss of function in breast tumor cells SO CANCER RESEARCH LA English DT Article ID DYSTROPHIN-GLYCOPROTEIN COMPLEX; MAMMARY-GLAND DEVELOPMENT; BASEMENT-MEMBRANE; EXTRACELLULAR-MATRIX; GENE-EXPRESSION; ALPHA-6-BETA-4 INTEGRIN; CONDITIONAL ABLATION; SUBMANDIBULAR-GLAND; ALPHA-DYSTROGLYCAN; BETA-1 INTEGRINS AB Receptors mediating cell-basement membrane interactions are potent regulators of epithelial architecture and function, and alterations in signals from the basement membrane are implicated in the aberrant behavior of carcinoma cells. In this study, we have investigated the role of the basement membrane receptor dystroglycan (DG) in mammary epithelial cell function, and the significance of loss of DG function in breast tumor cell lines. Nonmalignant mammary epithelial cells express a functional DG. Analysis of multiple breast carcinoma cell lines revealed that DG is expressed in all of the cell lines examined, as evidenced by beta-DG expression, but that alpha-DG is functionally diminished in the majority. High levels of alpha-DG correlated strongly with the ability of cells to polarize in the presence of the basement membrane. Overexpression of the DG cDNA in HMT-3522-T4-2 cells elevated alpha-DG levels and altered responsiveness to the basement membrane; DG overexpression restored the ability of the cells to undergo cytoskeletal changes, to polarize, and to restrict growth in response to basement membrane proteins. Moreover, restoration of DG function to these cells greatly reduced their tumorigenic potential in nude mice. These data point to DG as an important mediator of normal cell responses to the basement membrane, and as a significant variable in carcinoma cells, in which its frequent loss can contribute to aberrant cell behavior. C1 Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Iowa, Coll Med, Howard Hughes Med Inst, Dept Physiol & Biophys, Iowa City, IA 52242 USA. RP Muschler, J (reprint author), Calif Pacific Med Ctr, Inst Res, 2330 Clay St, San Francisco, CA 94115 USA. FU NCI NIH HHS [CA57621, CA64786, R01 CA057621-07, R01 CA064786-05] NR 58 TC 104 Z9 109 U1 0 U2 5 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 DEC 1 PY 2002 VL 62 IS 23 BP 7102 EP 7109 PG 8 WC Oncology SC Oncology GA 622HJ UT WOS:000179641000047 PM 12460932 ER PT J AU Krumpelt, M Krause, TR Carter, JD Kopasz, JP Ahmed, S AF Krumpelt, M Krause, TR Carter, JD Kopasz, JP Ahmed, S TI Fuel processing for fuel cell systems in transportation and portable power applications SO CATALYSIS TODAY LA English DT Article; Proceedings Paper CT 222nd ACS National Meeting CY AUG 26-30, 2001 CL CHICAGO, ILLINOIS SP ACS DE fuel cell systems; portable power applications; transportation; fuel processing; auto thermal reforming ID SYNTHESIS GAS-FORMATION; DIRECT OXIDATION; METHANE; SYNGAS; MONOLITHS; CATALYSTS; HYDROGEN AB Small fuel cell systems in the 1-100kW power range have become the focus of intense R&D activities. Applications envisioned for such systems include primary propulsion power for passenger cars and light-duty vehicles, auxiliary power for trucks and heavy-duty vehicles (for operator quality-of-life and housekeeping needs) and portable power generation for residential and recreational use. The operating mode of these small fuel cell systems differs dramatically from that of larger fuel cell systems (100-1000 kW) designed for utility power generation. These small systems will operate over a wide load range, with only brief periods at full power, considerable time at 30-50% of the rated power, and relatively frequent shutoffs and restarts. The lack of an infrastructure for producing and distributing H-2 has led to a research effort to develop on-board fuel processing technology for reforming hydrocarbon fuels to generate H-2. Existing reforming technology used in large-scale manufacturing operations, such as ammonia synthesis, is cost prohibitive when scaled down to the size of these small systems. Furthermore, these large reforming systems are designed to operate at a constant production rate and with infrequent shutoffs and restarts. In this paper, we provide an overview of the reforming options for generating H2 from hydrocarbon fuels, the development of new reforming catalysts, and the design of fuel processors for these small fuel cell systems. (C) 2002 Published by Elsevier Science B.V. C1 Argonne Natl Lab, Electrochem Technol Program, Div Chem Technol, Argonne, IL 60439 USA. RP Krumpelt, M (reprint author), Argonne Natl Lab, Electrochem Technol Program, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 38 TC 180 Z9 186 U1 1 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD DEC 1 PY 2002 VL 77 IS 1-2 BP 3 EP 16 AR PII S0920-5861(02)00230-4 DI 10.1016/S0920-5861(02)00230-4 PG 14 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 623MY UT WOS:000179708400002 ER PT J AU Chin, YH Dagle, R Hu, JL Dohnalkova, AC Wang, Y AF Chin, YH Dagle, R Hu, JL Dohnalkova, AC Wang, Y TI Steam reforming of methanol over highly active Pd/ZnO catalyst SO CATALYSIS TODAY LA English DT Article; Proceedings Paper CT 222nd ACS National Meeting CY AUG 26-30, 2001 CL CHICAGO, ILLINOIS SP ACS DE bimetallic catalyst; hydrogen production; palladium; zinc oxide catalyst; PdZn alloy ID PARTIAL OXIDATION; FUEL-CELLS; DECOMPOSITION; HYDROGEN; GAS; CO AB Pd/ZnO catalysts were investigated for steam reforming of methanol. Unlike precious metal-based catalysts, Pd/ZnO catalysts not only exhibited high activity, but more importantly very low selectivity to CO for methanol steam reforming. Under the conditions examined, the decomposition activity is minimal. The novel function is attributed to the formation of highly structured Pd--Zn alloy at moderate temperatures under mild reducing environments. The current catalytic system was characterized by TPR, transmission electron microscopy (TEM), H-2 chemisorption, and X-ray diffraction (XRD). (C) 2002 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Chin, YH (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd MSIN K8-93,POB 999, Richland, WA 99352 USA. RI Wang, Yong/C-2344-2013 NR 14 TC 164 Z9 173 U1 3 U2 63 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD DEC 1 PY 2002 VL 77 IS 1-2 BP 79 EP 88 AR PII S0920-5861(02)00234-1 DI 10.1016/S0920-5861(02)00234-1 PG 10 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 623MY UT WOS:000179708400006 ER PT J AU Carreras, BA Lynch, VE Dobson, I Newman, DE AF Carreras, BA Lynch, VE Dobson, I Newman, DE TI Critical points and transitions in an electric power transmission model for cascading failure blackouts SO CHAOS LA English DT Article ID SECURITY AB Cascading failures in large-scale electric power transmission systems are an important cause of blackouts. Analysis of North American blackout data has revealed power law (algebraic) tails in the blackout size probability distribution which suggests a dynamical origin. With this observation as motivation, we examine cascading failure in a simplified transmission system model as load power demand is increased. The model represents generators, loads, the transmission line network, and the operating limits on these components. Two types of critical points are identified and are characterized by transmission line flow limits and generator capability limits, respectively. Results are obtained for tree networks of a regular form and a more realistic 118-node network. It is found that operation near critical points can produce power law tails in the blackout size probability distribution similar to those observed. The complex nature of the solution space due to the interaction of the two critical points is examined. (C) 2002 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Wisconsin, ECE Dept, Madison, WI 53706 USA. Univ Alaska, Dept Phys, Fairbanks, AK 99775 USA. RP Carreras, BA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Dobson, Ian/C-3989-2008; Lynch, Vickie/J-4647-2012 OI Dobson, Ian/0000-0001-7018-5475; Lynch, Vickie/0000-0002-5836-7636 NR 20 TC 210 Z9 231 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 1054-1500 J9 CHAOS JI Chaos PD DEC PY 2002 VL 12 IS 4 BP 985 EP 994 DI 10.1063/1.1505810 PG 10 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 617ZX UT WOS:000179393000001 ER PT J AU Wang, LH Hingerty, BE AF Wang, LH Hingerty, BE TI Conformational analysis of model estrogen-DNA adducts, N-2-(2-hydroxyestron-6(alpha,beta)-yl)-2 '-deoxyguanosine and N-6-(2-hydroxyestron-6(alpha,beta)-yl)-2 ' deoxyadenosine in duplex B-DNA. SO CHEMICAL RESEARCH IN TOXICOLOGY LA English DT Meeting Abstract CT Meeting of the American-Chemical-Society Division of Chemical Toxicology of the 224th ACS National Meeting CY AUG 18-22, 2002 CL BOSTON, MASSACHUSETTS SP Amer Chem Soc, Div Chem Toxicol C1 NYU, Dept Biol, New York, NY 10003 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0893-228X J9 CHEM RES TOXICOL JI Chem. Res. Toxicol. PD DEC PY 2002 VL 15 IS 12 MA 67 BP 1667 EP 1668 PG 2 WC Chemistry, Medicinal; Chemistry, Multidisciplinary; Toxicology SC Pharmacology & Pharmacy; Chemistry; Toxicology GA 627VU UT WOS:000179957500087 ER PT J AU Paik, Y Grey, CP Johnson, CS Kim, JS Thackeray, MM AF Paik, Y Grey, CP Johnson, CS Kim, JS Thackeray, MM TI Lithium and deuterium NMR studies of acid-leached layered lithium manganese oxides SO CHEMISTRY OF MATERIALS LA English DT Article ID STRUCTURAL CHARACTERIZATION; POSITIVE ELECTRODE; CATHODE MATERIALS; MAS; LI2MNO3; BATTERIES; DIOXIDE; LIMN2O4; FORM; LI-6 AB Li-6 and H-2 MAS NMR in conjunction with X-ray diffraction is used to study the acid leaching of the layered Mn(IV) compound Li2MnO3 (i.e., Li[Li0.33Mn0.67]O-2). Lithium NMR shows that the lithium ions are progressively removed from the lithium layers during leaching, the reduction in lithium content in the layers correlating directly with the concentration of a new local environment for lithium that contains both manganese ions and protons in the first cation coordination sphere. The composition of these samples may be written as H1-xLix[Li0.33Mn0.67]O-2, indicating that H+/Li+ ion exchange has occurred. H-2 MAS NMR shows unequivocally that deuterons are present in these structures, following leaching in D2SO4/D2O. X-ray diffraction confirms that leaching is associated with the shearing of the oxygen layers to form a structure with an AABBCC stacking sequence of the oxygen layers. This stacking sequence is also found in isostructural compound HCrO2. The hydrogen bonding between the oxygen layers is proposed to provide the driving force for oxygen shearing so as to minimize the O-O distances between the "AA", "BB", and "CC" layers to generate stronger hydrogen bonding. Li+/H+ ion exchange is also accompanied by the loss of Li2O from the structure, which is more pronounced for Li2MnO3 samples calcined for shorter times. These samples can be cycled as positive electrodes (versus Li), providing capacities of more than 150 mA h g(-1). C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Grey, CP (reprint author), SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. NR 26 TC 82 Z9 84 U1 7 U2 68 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD DEC PY 2002 VL 14 IS 12 BP 5109 EP 5115 DI 10.1021/cm0206385 PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 628VE UT WOS:000180016600032 ER PT J AU Yu, KL Lee, CH Huang, JCA Su, HC Felcher, GP AF Yu, KL Lee, CH Huang, JCA Su, HC Felcher, GP TI Determination of depth profiles of Ni80Fe20 epifilms on Mo buffered Al2O3 substrates with and without a Co interlayer by polarized neutron and X-ray reflectivity SO CHINESE JOURNAL OF PHYSICS LA English DT Article ID EUROPEAN SPALLATION SOURCE; GIANT MAGNETORESISTANCE; INTERFACE ROUGHNESS; THIN-FILMS; REFLECTOMETER; SURFACES AB Polarized neutron and X-ray reflectivity are complementary tools used to measure the depth profile of magnetic thin films. In this work, permalloy thin films were epitaxially deposited on Mo buffered Al2O3 (1-100) substrates with a Co interlayer and without a Co interlayer. The interface structure between the permalloy and the Co layers, determined by X-ray reflectivity alone, was insensitive, due to the low contrast of the electron density between these two adjacent layers. It can however, be determined by polarized neutron reflectivity, due to the large difference of the nuclear scattering lengths and magnetic moments between these two layers. C1 Natl Tsing Hua Univ, Dept Engn & Syst Sci, Hsinchu 300, Taiwan. Natl Tsing Hua Univ, Nucl Reactor Div, Nucl Sci & Technol Dev Ctr, Hsinchu 300, Taiwan. Natl Cheng Kung Univ, Dept Phys, Tainan 701, Taiwan. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Yu, KL (reprint author), Natl Tsing Hua Univ, Dept Engn & Syst Sci, Hsinchu 300, Taiwan. OI Lee, Chih-Hao/0000-0002-3898-6421 NR 21 TC 7 Z9 7 U1 0 U2 2 PU PHYSICAL SOC REPUBLIC CHINA PI TAIPEI PA CHINESE JOURNAL PHYSICS PO BOX 23-30, TAIPEI 10764, TAIWAN SN 0577-9073 J9 CHINESE J PHYS JI Chin. J. Phys. PD DEC PY 2002 VL 40 IS 6 BP 616 EP 623 PG 8 WC Physics, Multidisciplinary SC Physics GA 627UY UT WOS:000179955600006 ER PT J AU Kapila, AK Schwendeman, DW Quirk, JJ Hawa, T AF Kapila, AK Schwendeman, DW Quirk, JJ Hawa, T TI Mechanisms of detonation formation due to a temperature gradient SO COMBUSTION THEORY AND MODELLING LA English DT Article ID INITIAL CONDITIONS; PLANE DETONATION; DEFLAGRATION; TRANSITION; EVOLUTION; FLAMES AB Emergence of a detonation in a homogeneous, exothermically reacting medium can be deemed to occur in two phases. The first phase processes the medium so as to create conditions ripe for the onset of-detonation. The actual events leading up to preconditioning may vary from one experiment to the next, but typically, at the end of this stage the medium is hot and in a state of nonuniformity. The second phase consists of the actual formation of the detonation wave via chemico-gasdynamic interactions. This paper considers an idealized medium with simple, rate-sensitive kinetics for which the preconditioned state is modelled as one with an initially prescribed linear gradient of temperature. Accurate and well-resolved numerical computations are carrried out to determine the mode of detonation formation as a function of the size of the initial gradient. For shallow gradients, the result is a decelerating supersonic reaction wave, a weak detonation, whose trajectory is dictated by the initial temperature profile, with only weak intervention from hydrodynamics. If the domain is long enough, or the gradient less shallow, the wave slows down to the Chapman-Jouguet speed and undergoes a swift transition to the ZND structure. For sharp gradients, gasdynamic nonlinearity plays a much stronger role. Now the path to detonation is through an accelerating pulse that runs ahead-of the reaction wave and rearranges the induction-time distribution there to one that bears little resemblance to that corresponding to the initial temperature gradient. The pulse amplifies and steepens, transforming itself into a complex consisting of a lead shock, an induction one, and a' following fast deflagration. As the pulse advances, its three constituent entities attain progressively higher levels of mutual coherence, to emerge as a ZND detonation. For initial gradients that are intermediate in size, aspects of both the extreme scenarios appear in the path to detonation. The novel aspect-of this study resides in the fact that it is guided by, and its results are compared with, existing asymptotic analyses of detonation evolution. C1 Rensselaer Polytech Inst, Troy, NY 12181 USA. Los Alamos Natl Lab, Los Alamos, NM USA. Univ Minnesota, Minneapolis, MN USA. RP Kapila, AK (reprint author), Rensselaer Polytech Inst, Troy, NY 12181 USA. EM kapila@rpi.edu NR 28 TC 45 Z9 48 U1 1 U2 11 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1364-7830 J9 COMBUST THEOR MODEL JI Combust. Theory Model. PD DEC PY 2002 VL 6 IS 4 BP 553 EP 594 AR PII S1364-7830(02)29057-9 DI 10.1088/1364-7830/6/4/302 PG 42 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Mathematics, Interdisciplinary Applications SC Thermodynamics; Energy & Fuels; Engineering; Mathematics GA 639KC UT WOS:000180626600002 ER PT J AU Fu, PD Rich, PM AF Fu, PD Rich, PM TI A geometric solar radiation model with applications in agriculture and forestry SO COMPUTERS AND ELECTRONICS IN AGRICULTURE LA English DT Article; Proceedings Paper CT 2nd International Conference on Geospatial Information in Agriculture and Forestry CY JAN 10-12, 2000 CL FLORIDA DE environmental modeling; geographical information systems; GIS; insolation; solar radiation maps; temperature maps ID MOUNTAINOUS TERRAIN; GIS AB Incoming solar radiation (insolation) is fundamental to most physical and biophysical processes because of its role in energy and water balance. We calculated insolation maps from digital elevation models, using an insolation model that accounts for atmospheric conditions, elevation, surface orientation, and influences of surrounding topography. Herein, we focus on the application of this insolation model for spatial interpolation of soil temperature measurements over complex topography at landscape scales. Existing interpolation techniques generally apply only at continental or broad regional scales and do not capture the high variation of finer scales. In our field study in the vicinity of the Rocky Mountain Biological Laboratory, average soil temperature was correlated with insolation and elevation. Whereas daily minimum temperature was negatively correlated with elevation (r = -0.730, P < 0.05), daily temperature change (maximum minus minimum) was positively correlated with daily insolation (r = 0.504, P < 0.01). We generated daily minimum and maximum soil temperature maps based on regression analyses. Residual variation was explained by factors such as vegetation cover. This application demonstrates the importance of characterizing spatial and temporal variation of insolation for studies of energy and water balance. (C) 2002 Published by Elsevier Science B.V. C1 Univ Kansas, Dept Geog, Lawrence, KS 66045 USA. Univ Kansas, Kansas Appl Remote Sensing Program, Lawrence, KS 66045 USA. Los Alamos Natl Lab, Environm Proc & Spatial Anal Grp, Los Alamos, NM 87545 USA. RP Fu, PD (reprint author), Environm Syst Res Inst, Redlands, CA USA. NR 28 TC 154 Z9 169 U1 1 U2 47 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0168-1699 J9 COMPUT ELECTRON AGR JI Comput. Electron. Agric. PD DEC PY 2002 VL 37 IS 1-3 SI SI BP 25 EP 35 AR PII S0168-1699(02)00115-1 DI 10.1016/S0168-1699(02)00115-1 PG 11 WC Agriculture, Multidisciplinary; Computer Science, Interdisciplinary Applications SC Agriculture; Computer Science GA 628UB UT WOS:000180014000004 ER PT J AU Labotka, TC Anovitz, LM Blencoe, JG AF Labotka, TC Anovitz, LM Blencoe, JG TI Pore pressure during metamorphism of carbonate rock: effect of volumetric properties of H2O-CO2 mixtures SO CONTRIBUTIONS TO MINERALOGY AND PETROLOGY LA English DT Article ID CO2-H2O SYSTEM; FLUID-FLOW; EQUATION; MPA; 400-DEGREES-C; EVOLUTION; AUREOLE; COMPLEX; STATE AB The molar volume of mixtures Of CO2 and H2O is a strong function of the fluid composition. Both CO2 and H2O participate in the metamorphism of carbonate rocks, resulting in a change in the fluid composition during reaction. One of the effects of the change in composition is the increase in pore-fluid pressure with only small increases in extent of reaction xi. Pressure calculated from the volumetric properties Of CO2-H2O mixtures at 400 degreesC increases greatly with small increases of but drops at greater values because of the increase in pore volume as a result of DeltaV(solid). The pore pressure increase at small values of xi, though, readily exceeds the reported tensile strength of carbonate rocks, and the rock cannot sustain significant reaction without fracturing. The result of a small amount of reaction is a fractured rock with increased permeability, which promotes fluid transport. C1 Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Labotka, TC (reprint author), Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. RI Anovitz, Lawrence/P-3144-2016 OI Anovitz, Lawrence/0000-0002-2609-8750 NR 26 TC 7 Z9 8 U1 1 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0010-7999 J9 CONTRIB MINERAL PETR JI Contrib. Mineral. Petrol. PD DEC PY 2002 VL 144 IS 3 BP 305 EP 313 DI 10.1007/s00410-002-0398-x PG 9 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 628XC UT WOS:000180021000004 ER PT J AU Klein, SL Strausberg, RL Wagner, L Pontius, J Clifton, SW Richardson, P AF Klein, SL Strausberg, RL Wagner, L Pontius, J Clifton, SW Richardson, P CA Washington Univ Est Sequencing Grp Natl Inst Hlth Xenopus Working Grp TI Genetic and genomic tools for Xenopus research: The NIH Xenopus initiative SO DEVELOPMENTAL DYNAMICS LA English DT Article DE Xenopus laevis; Xenopus tropicalis; resources; ESTs; cDNA libraries; genomic libraries AB The NIH Xenopus Initiative is establishing many of the genetic and genomic resources that have been recommended by the Xenopus research community. These resources include cDNA libraries, expressed sequence tags, full-length cDNA sequences, genomic libraries, pilot projects to mutagenize and phenotype X. tropicalis, and sequencing the X. tropicalis genome. This review describes the status of these projects and explains how to access their data and resources. Current information about these activities is available on the NIH Xenopus Web site (http://www.nih.gov/science/models/xenopus/). Published 2002 Wiley-Liss, Inc.(dagger) C1 NICHHD, Genet & Teratol Branch, Rockville, MD 20852 USA. NCI, Canc Genom Off, Bethesda, MD 20892 USA. Natl Lib Med, Natl Ctr Biotechnol Informat, Bethesda, MD 20894 USA. Washington Univ, Sch Med, Genome Sequencing Ctr, St Louis, MO 63130 USA. US DOE, Joint Genome Inst, Walnut Creek, CA USA. RP Klein, SL (reprint author), NICHHD, Genet & Teratol Branch, Room 4B01,6100 Execut Blvd, Rockville, MD 20852 USA. NR 0 TC 201 Z9 221 U1 1 U2 6 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1058-8388 J9 DEV DYNAM JI Dev. Dyn. PD DEC PY 2002 VL 225 IS 4 BP 384 EP 391 DI 10.1002/dvdy.10174 PG 8 WC Anatomy & Morphology; Developmental Biology SC Anatomy & Morphology; Developmental Biology GA 622FJ UT WOS:000179635700004 PM 12454917 ER PT J AU Bissell, MJ Radisky, DC Rizki, A Weaver, VM Petersen, OW AF Bissell, MJ Radisky, DC Rizki, A Weaver, VM Petersen, OW TI The organizing principle: microenvironmental influences in the normal and malignant breast SO DIFFERENTIATION LA English DT Review DE breast tissue; luminal epithelial cells; myoepithelial cells; breast cancer; 3D cultures ID MAMMARY EPITHELIAL-CELLS; FLOATING COLLAGEN MEMBRANES; BASEMENT-MEMBRANE; GENE-EXPRESSION; NUCLEAR-ORGANIZATION; TISSUE STRUCTURE; IN-VIVO; CULTURE; DIFFERENTIATION; CANCER AB The current paradigm for cancer initiation and progression rests on the groundbreaking discoveries of oncogenes and tumor suppressor genes. This framework has revealed much about the role of genetic alterations in the underlying signaling pathways central to normal cellular function and to tumor progression. However, it is clear that single gene theories or even sequential acquisition of mutations underestimate the nature of the genetic and epigenetic changes in tumors, and do not account for the observation that many cancer susceptibility genes (e. g. BRCA1, APC) show a high degree of tissue specificity in their association with neoplastic transformation. Therefore, the cellular and tissue context itself must confer additional and crucial information necessary for mutated genes to exert their influence. A considerable body of evidence now shows that cell-cell and cell-extracellular matrix (ECM) interactions are essential organizing principles that help define the nature of the tissue context, and play a crucial role in regulating homeostasis and tissue specificity. How this context determines functional integrity, and how its loss can lead to malignancy, appears to have much to do with tissue structure and polarity. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Penn, Dept Pathol, Philadelphia, PA 19104 USA. Univ Penn, Inst Med & Engn, Philadelphia, PA 19104 USA. Univ Copenhagen, Panum Inst, Inst Med Anat, Struct Cell Biol Unit, DK-2200 Copenhagen, Denmark. RP Bissell, MJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd,MS 83-101, Berkeley, CA 94720 USA. FU NCI NIH HHS [CA57621, CA64786-02, R01 CA057621, R01 CA057621-07, R01 CA064786, R01 CA064786-04A1, R37 CA064786] NR 37 TC 318 Z9 332 U1 0 U2 25 PU BLACKWELL VERLAG GMBH PI BERLIN PA KURFURSTENDAMM 57, D-10707 BERLIN, GERMANY SN 0301-4681 J9 DIFFERENTIATION JI Differentiation PD DEC PY 2002 VL 70 IS 9-10 BP 537 EP 546 DI 10.1046/j.1432-0436.2002.700907.x PG 10 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA 627QX UT WOS:000179946700007 PM 12492495 ER PT J AU Um, W Papelis, C AF Um, W Papelis, C TI Geochemical effects on colloid-facilitated metal transport through zeolitized tuffs from the Nevada Test Site SO ENVIRONMENTAL GEOLOGY LA English DT Article DE colloids; Pb(II); sorption; colloid-facilitated transport; zeolitized tuffs; Nevada Test Site (NTS), Nevada, USA ID POROUS-MEDIA; WATER INTERFACE; PARTICLES; CONTAMINANTS; GROUNDWATER; KAOLINITE; SORPTION; KINETICS; PB(II) AB Natural colloids were generated from zeolitized tuffs from the Nevada Test Site (NTS) and the effects of colloids on the transport of a strongly sorbing metal, lead [Pb(II)], were investigated in column experiments under different geochemical conditions. Because of the high sorption affinity of Pb(II) for zeolitized tuffs, the migration of Pb(II) without colloids was strongly retarded. The presence of mobile colloids, however, enhanced the mobility of Pb(II). Approximately 75-90% of the eluted Pb(II) was transported as a colloid-associated phase. The migration of colloids was closely related to the geochemical conditions in the background solution. Immobilization of colloids increased as the ionic strength of the background electrolyte solution increased, because of double layer compaction. Remobilization of initially deposited colloids occurred when the ionic strength of the background electrolyte solution was reduced. The mobility of colloids increased with increasing pH and increasing flow rates. These results have significant implications for the migration of strongly sorbing radionuclides and other metals at nuclear testing facilities and metal-contaminated sites and are consistent with the hypothesis that inorganic contaminant migration in the subsurface is a function of geochemical conditions. C1 Desert Res Inst, Div Hydrol Sci, Las Vegas, NV 89119 USA. RP Um, W (reprint author), Pacific NW Natl Lab, POB 999,K6-81, Richland, WA 99352 USA. NR 36 TC 25 Z9 29 U1 6 U2 22 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0943-0105 J9 ENVIRON GEOL JI Environ. Geol. PD DEC PY 2002 VL 43 IS 1-2 BP 209 EP 218 DI 10.1007/s00254-002-0646-4 PG 10 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 629DP UT WOS:000180035400022 ER PT J AU Pepper, IL Gentry, TJ Newby, DT Roane, TM Josephson, KL AF Pepper, IL Gentry, TJ Newby, DT Roane, TM Josephson, KL TI The role of cell bioaugmentation and gene bioaugmentation in the remediation of co-contaminated soils SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article; Proceedings Paper CT Conference on Application of Technology to Chemical Mixture Research CY JAN, 2001 CL COLORADO STATE UNIV, FT COLLINS, COLORADO SP Natl Inst Environm Hlth Sci, Superfund Basic Res Program HO COLORADO STATE UNIV DE 2,4-dichlorophenoxyacetic acid; bioaugmentation; bioremediation; co-contaminated soil; gene transfer; heavy metals ID BACTERIAL COMMUNITIES; HEAVY-METALS; PLASMID PJP4; 3-CHLOROBENZOATE; POPULATIONS AB Soils co-contaminated with metals and organics present special problems for remediation. Metal contamination can delay or inhibit microbial degradation of organic pollutants such that for effective in situ biodegradation, bioaugmentation is necessary. We monitored the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) or 3-chlorobenzoate (3-CB) in two different soils with and without cadmium (Cd) contamination. Additionally, we evaluated the ability of bioaugmentation to enhance organic degradation in these co-contaminated soils. Finally, we determined whether enhanced degradation was due to survival of the introduced organism (cell bioaugmentation) or plasmid transfer to indigenous microbial populations (gene bioaugmentation). In Brazito soil, dual inoculation with a Cd-resistant bacterium plus a known 2,4-D-degrading bacterium, Ralstonia eutropha JMP 134, enhanced 2,4-D degradation. Escherichia coli D 11, which lacks chromosomal genes necessary for complete 2,4-D mineralization, was used for gene bioaugmentation in Madera soil. Significant gene transfer of the plasmid to the indigenous populations was observed, and the rate of 2,4-D degradation was enhanced relative to that of controls. Cell bioaugmentation was further demonstrated when Comamonas testosteroni was used to enhance biodegradation of 3-CB in Madera soil. In this case no transfer of plasmid pBRC60 to indigenous soil recipients was observed. For the Madera soil, nonbioaugmented samples ultimately showed complete 2,4-D degradation. In contrast, nonbioaugmented Brazito soils showed incomplete 2,4-D degradation. These studies are unique in showing that both cell bioaugmentation and gene bioaugmentation can be effective in enhancing organic degradation in co-contaminated soils. Ultimately, the bioaugmentation strategy may depend on the degree of contamination and the time frame available for remediation. http://ehpnet1.niehs.nih.gov/docs/2002/suppl-6/943 -946pepper/abstract.html. C1 Univ Arizona, Tucson, AZ USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. Univ Colorado, Denver, CO 80202 USA. RP Pepper, IL (reprint author), 2601 E Airport Dr, Tucson, AZ 85706 USA. FU NIEHS NIH HHS [5P42 ES04940-07] NR 18 TC 38 Z9 41 U1 1 U2 13 PU US DEPT HEALTH HUMAN SCIENCES PUBLIC HEALTH SCIENCE PI RES TRIANGLE PK PA NATL INST HEALTH, NATL INST ENVIRONMENTAL HEALTH SCIENCES, PO BOX 12233, RES TRIANGLE PK, NC 27709-2233 USA SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD DEC PY 2002 VL 110 SU 6 BP 943 EP 946 PG 4 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 644RA UT WOS:000180932100009 PM 12634123 ER PT J AU Vogel, JS Keating, GA Buchholz, BA AF Vogel, JS Keating, GA Buchholz, BA TI Protein binding of isofluorophate in vivo after coexposure to multiple chemicals SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article; Proceedings Paper CT Conference on Application of Technology to Chemical Mixture Research CY JAN, 2001 CL COLORADO STATE UNIV, FT COLLINS, COLORADO SP Natl Inst Environm Hlth Sci, Superfund Basic Res Program HO COLORADO STATE UNIV DE accelerator mass spectrometry; chemical mixture; diisopropylfluorophosphate; esterase; organophosphate; parathion; permethrin; pyrethroid; radioisotope ID RAT-BRAIN; IN-VITRO; EXPOSURE; ACETYLCHOLINESTERASE; PYRIDOSTIGMINE; TOXICITY; PHOSPHOROFLUORIDATE; ANTICHOLINESTERASES; CHOLINESTERASE; INSECTICIDES AB Full toxicologic profiles of chemical mixtures, including dose-response extrapolations to realistic exposures, is a prohibitive analytical problem, even for a restricted class of chemicals. We present an approach to probing in vivo interactions of pesticide mixtures at relevant low doses using a monitor compound to report the response of biochemical pathways shared by mixture components. We use accelerator mass spectrometry (AMS) to quantify [C-14]-diisopropylfluorophosphate as a tracer at attomole levels with 1-5% precision after coexposures to parathion (PTN), permethrin (PER), and pyridostigmine bromide separately and in conjunction. Pyridostigmine shows an overall protective effect against tracer binding in plasma, red blood cells, muscle, and brain that is not explained as competitive protein binding. PTN and PER induce a significant 25-30% increase in the amount of tracer reaching the brain with or without pyridostigmine. The sensitivity of AMS for isotope-labeled tracer compounds can be used to probe the physiologic responses of specific biochemical pathways to multiple compound exposures. C1 Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. RP Vogel, JS (reprint author), Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, 7000 East Ave,L-397, Livermore, CA 94551 USA. RI Buchholz, Bruce/G-1356-2011 FU NCRR NIH HHS [P41 RR013461, RR13461]; NIEHS NIH HHS [ES 09690] NR 34 TC 11 Z9 12 U1 0 U2 3 PU US DEPT HEALTH HUMAN SCIENCES PUBLIC HEALTH SCIENCE PI RES TRIANGLE PK PA NATL INST HEALTH, NATL INST ENVIRONMENTAL HEALTH SCIENCES, PO BOX 12233, RES TRIANGLE PK, NC 27709-2233 USA SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD DEC PY 2002 VL 110 SU 6 BP 1031 EP 1036 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 644RA UT WOS:000180932100021 PM 12634135 ER PT J AU Rowe, CL Hopkins, WA Congdon, JD AF Rowe, CL Hopkins, WA Congdon, JD TI Ecotoxicological implications of aquatic disposal of coal combustion residues in the United States: A review SO ENVIRONMENTAL MONITORING AND ASSESSMENT LA English DT Review DE accumulation; aquatic animals; coal ash; electric power; energy; heavy metals; sublethal effects; trace elements ID TRACE-ELEMENT CONCENTRATIONS; BULLFROGS RANA-CATESBEIANA; STANDARD METABOLIC-RATE; WATER-QUALITY CRITERIA; FLY-ASH; BUFO-TERRESTRIS; LARGEMOUTH BASS; SOUTHERN TOADS; INORGANIC CONSTITUENTS; SELENIUM ACCUMULATION AB We provide an overview of research related to environmental effects of disposal of coal combustion residues (CCR) in sites in the United States. Our focus is on aspects of CCR that have the potential to negatively influence aquatic organisms and the health of aquatic ecosystems. We identify major issues of concern, as well as areas in need of further investigation. Intentional or accidental release of CCR into aquatic systems has generally been associated with deleterious environmental effects. A large number of metals and trace elements are present in CCR, some of which are rapidly accumulated to high concentrations by aquatic organisms. Moreover, a variety of biological responses have been observed in organisms following exposure to and accumulation of CCR-related contaminants. In some vertebrates and invertebrates, CCR exposure has led to numerous histopathological, behavioral, and physiological (reproductive, energetic, and endocrinological) effects. Fish kills and extirpation of some fish species have been associated with CCR release, as have indirect effects on survival and growth of aquatic animals mediated by changes in resource abundance or quality. Recovery of CCR-impacted sites can be extremely slow due to continued cycling of contaminants within the system, even in sites that only received CCR effluents for short periods of time. The literature synthesis reveals important considerations for future investigations of CCR-impacted sites. Many studies have examined biological responses to CCR with respect to Se concentrations and accumulation because of teratogenic and reproductively toxic effects known to be associated with this element. However, the complex mixture of metals and trace elements characteristic of CCR suggests that biological assessments of many CCR-contaminated habitats should examine a variety of inorganic compounds in sediments, water, and tissues before causation can be linked to individual CCR components. Most evaluations of effects of CCR in aquatic environments have focused on lentic systems and the populations of animals occupying them. Much less is known about CCR effects in lotic systems, in which the contaminants may be transported downstream, diluted or concentrated in downstream areas, and accumulated by more transient species. Although some research has examined accumulation and effects of contaminants on terrestrial and avian species that visit CCR-impacted aquatic sites, more extensive research is also needed in this area. Effects in terrestrial or semiaquatic species range from accumulation and maternal transfer of elements to complete recruitment failure, suggesting that CCR effects need to be examined both within and outside of the aquatic habitats into which CCR is released. Requiring special attention are waterfowl and amphibians that use CCR-contaminated sites during specific seasons or life stages and are highly dependent on aquatic habitat quality during those periods. Whether accidentally discharged into natural aquatic systems or present in impoundments that attract wildlife, CCR appears to present significant risks to aquatic and semiaquatic organisms. Effects may be as subtle as changes in physiology or as drastic as extirpation of entire populations. When examined as a whole, research on responses of aquatic organisms to CCR suggests that reducing the use of disposal methods that include an aquatic slurry phase may alleviate some environmental risks associated with the waste products. C1 Univ Maryland, Chesapeake Biol Lab, Ctr Environm Sci, Solomons, MD 20688 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC USA. RP Rowe, CL (reprint author), Univ Maryland, Chesapeake Biol Lab, Ctr Environm Sci, Solomons, MD 20688 USA. RI Rowe, Christopher/D-5271-2012 NR 115 TC 98 Z9 100 U1 9 U2 72 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-6369 J9 ENVIRON MONIT ASSESS JI Environ. Monit. Assess. PD DEC PY 2002 VL 80 IS 3 BP 207 EP 276 DI 10.1023/A:1021127120575 PG 70 WC Environmental Sciences SC Environmental Sciences & Ecology GA 616UT UT WOS:000179322300001 PM 12503897 ER PT J AU Klara, SM Srivastava, RD AF Klara, SM Srivastava, RD TI US DOE integrated collaborative technology development program for CO2 separation and capture SO ENVIRONMENTAL PROGRESS LA English DT Article AB Electric power generation represents one of the largest carbon dioxide CO2 emitters in the United States. Roughly one-third of all the United States' carbon emissions come from power plants. Since electricity generation is expected to grow, and fossil fuels will continue to be the dominant fuel source, power generation can be expected to provide even greater CO2 contributes in the future. Consequently, an important component of the United States Department of Energy's (DOE's) research and development program is dedicated to reducing CO2 emissions from power plants by developing technologies to capture CO2 for utilization and/or sequestration. A primary goal of this research is to develop technology options that dramatically lower the cost of eliminating CO2 from flue gas and other streams by use of either pre- or post-combustion processes. This research is in its early stages, and is exploring a wide range of approaches, including membranes, improved CO2 sorbents, advanced scrubbing, oxyfuel combustors, formation of CO2 hydrates, and economic assessments. This paper presents an overview of the DOE research program in the area of CO2 separation and capture, while specifically addressing the status of research efforts related to promising pathways and potential technological breakthroughs. C1 US DOE, Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. Sci Applicat Int Corp, Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. RP Klara, SM (reprint author), US DOE, Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. NR 4 TC 63 Z9 64 U1 1 U2 19 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 3 PARK AVE, NEW YORK, NY 10016-5901 USA SN 0278-4491 J9 ENVIRON PROG JI Environ. Prog. PD DEC PY 2002 VL 21 IS 4 BP 247 EP 253 DI 10.1002/ep.670210414 PG 7 WC Engineering, Environmental; Engineering, Chemical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 719VM UT WOS:000185225800009 ER PT J AU Fruchter, J AF Fruchter, J TI In situ treatment of chromium-contaminated groundwater SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID HEXAVALENT CHROMIUM; REMEDIATION; REDUCTION; CHROMATE; SUBSURFACE; BARRIER C1 Pacific NW Natl Lab, Environm Technol Directorate, Richland, WA 99352 USA. RP Fruchter, J (reprint author), Pacific NW Natl Lab, Environm Technol Directorate, Richland, WA 99352 USA. NR 35 TC 37 Z9 37 U1 4 U2 40 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 DEC 1 PY 2002 VL 36 IS 23 BP 464A EP 472A DI 10.1021/es022466i PG 9 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 623CE UT WOS:000179685000004 PM 12523403 ER PT J AU Laskin, A Iedema, MJ Cowin, JP AF Laskin, A Iedema, MJ Cowin, JP TI Quantitative time-resolved monitoring of nitrate formation in sea salt particles using a CCSEM/EDX single particle analysis SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID MARINE BOUNDARY-LAYER; AIR MASSES; AEROSOL; CHEMISTRY; MICROANALYSIS; COMPONENTS; ATMOSPHERE; CHLORIDE; PACIFIC; SULFUR AB Progress of the nitrate formation in individual sea salt particles was detected as a function of time using aerosol samples collected during the TexAQS 2000 experiment. We demonstrate that the time-resolved collection approach coupled with the automated EDX single particle analysis made it possible to follow in detail the time evolution of sea salt particles within a diverse aerosol mixture. Using a custom built Time-Resolved Aerosol Collector (TRAC), particulate samples were taken sequentially on grid-supported 50 nm carbon films with a time resolution of 10 min between two consecutive samples. The samples were analyzed in the laboratory using Computer Controlled Scanning Electron Microscopy with Energy-Dispersed analysis of X-rays (CCSEM/EDX). Between midnight of 08/16/00 and the early morning of 08/17/00, a steady, particularly sea salt rich aerosol was observed at the measurement site, which later showed the effects of atmospheric processing. During the night of 08/17/00 the sea salt particles were almost unprocessed, having elemental composition close to that of seawater. By 12 noon,the evolving atmosphere was able to completely convert them, predominantly to sodium nitrate particles. During the next night, this process had nearly stopped and fairly virgin sea salt particles appeared again. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Laskin, A (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,MSIN K8-88, Richland, WA 99352 USA. RI Laskin, Alexander/I-2574-2012 OI Laskin, Alexander/0000-0002-7836-8417 NR 41 TC 51 Z9 51 U1 2 U2 19 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 DEC 1 PY 2002 VL 36 IS 23 BP 4948 EP 4955 DI 10.1021/es020551k PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 623CE UT WOS:000179685000006 PM 12523405 ER PT J AU Hintelmann, H Harris, R Heyes, A Hurley, JP Kelly, CA Krabbenhoft, DP Lindberg, S Rudd, JWM Scott, KJ St Louis, VL AF Hintelmann, H Harris, R Heyes, A Hurley, JP Kelly, CA Krabbenhoft, DP Lindberg, S Rudd, JWM Scott, KJ St Louis, VL TI Reactivity and mobility of new and old mercury deposition in a Boreal forest ecosystem during the first year of the METAALICUS study SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID AIR/SURFACE EXCHANGE; METHYL MERCURY; METHYLMERCURY; ENVIRONMENT; TRANSPORT; DYNAMICS; ISOTOPES; RUNOFF; CYCLE; LAKE AB The METAALICUS (Mercury Experiment To Assess Atmospheric Loading In Canada and the US) project is a whole ecosystem experiment designed to study the activity, mobility, and availability of atmospherically deposited mercury. To investigate the dynamics of mercury newly deposited onto a terrestrial ecosystem, an enriched stable isotope of mercury (Hg-202) was sprayed onto a Boreal forest subcatchment in an experiment that allowed us, for the first time, to monitor the fate of "new" mercury in deposition and to distinguish it from native mercury historically stored in the ecosystem. Newly deposited mercury was more reactive than the native mercury with respect to volatilization and methylation pathways. Mobility through runoff was very low and strongly decreased with time because of a rapid equilibration with the large native pool of "bound" mercury. Over one season, only similar to8% of the added Hg-202 volatilized to the atmosphere and less than 1% appeared in runoff. Within a few months, approximately 66% of the applied Hg-202 remained associated with above ground vegetation, with the rest being incorporated into soils. The fraction of 202Hg bound to vegetation was much higher than seen for native Hg (<5% vegetation), suggesting that atmospherically derived mercury enters the soil pool with a time delay, after plants senesce and decompose. The initial mobility of mercury received through small rain events or dry deposition decreased markedly in a relatively short time period, suggesting that mercury levels in terrestrial runoff may respond slowly to changes in mercury deposition rates. C1 Tetra Tech Inc, Oakville, ON L6J 4E6, Canada. Univ Maryland, Chesapeake Biol Lab, Solomons, MD 20688 USA. Univ Wisconsin, Water Resources Inst, Madison, WI 53706 USA. Fisheries & Oceans Canada, Inst Freshwater, Winnipeg, MB R3T 2N6, Canada. US Geol Survey WRD, Middleton, WI 53562 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Manitoba, Dept Microbiol, Winnipeg, MB R3T 2N2, Canada. Univ Alberta, Dept Sci Biol, Edmonton, AB T6G 2E9, Canada. Trent Univ, Dept Chem, Peterborough, ON K9J 7B8, Canada. RP Hintelmann, H (reprint author), Trent Univ, Dept Chem, 1600 West Bank Dr, Peterborough, ON K9J 7B8, Canada. EM hhintelmann@trentu.ca RI Hurley, James/A-9216-2010; St. Louis, Vincent/G-6842-2011; Heyes, Andrew/E-5269-2012; St. Louis, Vincent/A-3757-2014; Mason, Robert/A-6829-2011; Guzman Bernardo, Francisco Javier/E-4183-2010; OI Guzman Bernardo, Francisco Javier/0000-0002-2210-8309; Hintelmann, Holger/0000-0002-5287-483X NR 33 TC 154 Z9 162 U1 11 U2 63 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X EI 1520-5851 J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 1 PY 2002 VL 36 IS 23 BP 5034 EP 5040 DI 10.1021/es025572t PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 623CE UT WOS:000179685000018 PM 12523417 ER PT J AU Smith, DH Wilder, JW Seshadri, K AF Smith, DH Wilder, JW Seshadri, K TI Thermodynamics of carbon dioxide hydrate formation in media with broad pore-size distributions SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID POROUS-MEDIA; DISSOCIATION; CO2; SEDIMENTS; METHANE AB Equilibrium pressures for the dissociation of carbon dioxide hydrates confined in silica gel pores of nominal radii 7.5, 5.0, and 3.0 nm were measured over a wide temperature range and were observed to be higher than those for bulk carbon dioxide hydrate. Models that have been previously reported in the literature are used to determine the pore radius involved in each equilibrium associated with these data, exactly reproducing the experiment a[ equilibrium pressure. Based on these models, pore volume distributions are reconstructed and compared to those obtained from nitrogen desorption isotherms. This comparison indicates that in the nominal 7.5 nm pores the hydrate formed nearly uniformly in the available pores, while in the nominal 5.0 and 3.0 nm pores-it did not. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA. Parsons Infrastructure & Technol Grp, Morgantown, WV 26505 USA. W Virginia Univ, Dept Math, Morgantown, WV 26506 USA. RP Wilder, JW (reprint author), US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. EM wilder@math.wvu.edu NR 20 TC 25 Z9 29 U1 1 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X EI 1520-5851 J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 1 PY 2002 VL 36 IS 23 BP 5192 EP 5198 DI 10.1021/es015862u PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 623CE UT WOS:000179685000038 PM 12523437 ER PT J AU Pang, YB Gundel, LA Larson, T Finn, D Liu, LJS Claiborn, CS AF Pang, YB Gundel, LA Larson, T Finn, D Liu, LJS Claiborn, CS TI Development and evaluation of a personal particulate organic and mass sampler SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; LOS-ANGELES BASIN; CHEMICAL-COMPOSITION; SIZE DISTRIBUTION; AEROSOL SAMPLERS; QUARTZ FILTERS; SYSTEM; PM2.5; ATMOSPHERE; ADSORPTION AB Accurate measurement of personal exposure to particulate matter and its constituents requires samplers that are accurate, compact, lightweight, inexpensive, and convenient to use. The personal particulate organic and mass sampler (PPOMS) has been developed to meet these criteria. The PPOMS uses activated carbon-impregnated foam as a combined 2.5-mum size-selective inlet and denuder for assessment of fine particle mass and organic carbon. Proof of the PPOMS concept has been established by comparing mass and organic carbon in particles collected with collocated samplers in Seattle, at a central outdoor site, and in residences. Daily particulate mass concentrations averaged 10.0 +/- 5.2, 12.0 +/- 5.3, and 11.2 +/- 5.1 mug m(-3) for the Federal Reference Method, the Harvard Personal Exposure Monitor, and the PPOMS, respectively, for 10 24-h sampling periods. During a series Of PM2.5 indoor organic carbon (OC) measurements from single quartz filters, the apparent indoor OC averaged 7.7 +/- 0.8 mug of C m(-3) which was close to the indoor PM2.5 mass from collocated Teflon filters (7.3 +/- 2.3 mug of C m(-3)), indicating the presence of a large positive OC artifact. In collocated measurements, the PPOMS eliminated this artifact just as well as the integrated gas and particle sampler that incorporated a macroreticular polystyrene-divinylbenzene (XAD-4) resin-coated denuder, yielding OC concentrations of 2.5 +/- 0.4 and 2.4 +/- 1.0 mug of C m(-3), respectively. Thermal analysis for OC indicated that the indoor positive artifact was due to adsorption of gas-phase semivolatile organic compounds (SVOC). This study shows that the PPOMS design provides a 2.5-mum size-selective inlet that also prevents the adsorption of gas-phase SVOC onto quartz filters, thus eliminating the filter positive artifact. The PPOMS meets a significant current challenge for indoor and personal sampling of particulate organic carbon. The PPOMS design can also simplify accurate ambient sampling for PM2.5. C1 Washington State Univ, Dept Civil & Environm Engn, Pullman, WA 99164 USA. Univ Calif Berkeley, Ernest Orlando Lawrence Berkley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Washington, Dept Environm Hlth, Seattle, WA 98195 USA. Univ Washington, Dept Civil & Environm Engn, Seattle, WA 98195 USA. RP Claiborn, CS (reprint author), Washington State Univ, Dept Civil & Environm Engn, Pullman, WA 99164 USA. NR 36 TC 15 Z9 15 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 1 PY 2002 VL 36 IS 23 BP 5205 EP 5210 DI 10.1021/es020639y PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 623CE UT WOS:000179685000040 PM 12523439 ER PT J AU Ruiz-Aguilar, GML Fernandez-Sanchez, JM Kane, SR Kim, D Alvarez, PJJ AF Ruiz-Aguilar, GML Fernandez-Sanchez, JM Kane, SR Kim, D Alvarez, PJJ TI Effect of ethanol and methyl-tert-butyl ether on monoaromatic hydrocarbon biodegradation: Response variability for different aquifer materials under various electron-accepting conditions SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE monoaromatic hydrocarbons; oxygenates; substrate interactions; degradation kinetics; natural attenuation ID ANAEROBIC DEGRADATION; O-XYLENE; MTBE; MICROORGANISMS; TOLUENE; BTEX; CULTURE; ALCOHOL; NITRATE AB Aquifer microcosms were used to determine how ethanol and methyl-tert-butyl ether (MtBE) affect monoaromatic hydrocarbon degradation under different electron-accepting conditions commonly found in contaminated sites experiencing natural attenuation. Response variability was investigated by using aquifer material from four sites with different exposure history. The lag phase prior to benzene, toluene, ethylbenzene, and xylenes (BTEX) and ethanol degradation was typically shorter in microcosms with previously contaminated aquifer material, although previous exposure did not always result in high degradation activity. Toluene was degraded in all aquifer materials and generally under a broader range of electron-accepting conditions compared to benzene, which was degraded only under aerobic conditions. The MtBE was not degraded within 100 d under any condition, and it did not affect BTEX or ethanol degradation patterns. Ethanol was often degraded before BTEX compounds and had a variable effect on BTEX degradation as a function of electron-accepting conditions and aquifer material source. An occasional enhancement of toluene degradation by ethanol occurred in denitrifying microcosms with unlimited nitrate; this may be attributable to the fortuitous growth of toluene-degrading bacteria during ethanol degradation. Nevertheless, experiments with flow-through aquifer columns showed that this beneficial effect could be eclipsed by an ethanol-driven depletion of electron acceptors, which significantly inhibited BTEX degradation and is probably the most important mechanism by which ethanol could hinder BTEX natural attenuation. A decrease in natural attenuation could increase the likelihood that BTEX compounds reach a receptor as well as the potential duration of exposure. C1 Univ Iowa, Dept Civil & Environm Engn, Iowa City, IA 52245 USA. Lawrence Livermore Natl Lab, Environm Restorat Div, Livermore, CA 94550 USA. Inje Univ, Dept Chem Engn, Kimhae 621749, Kyongnam, South Korea. RP Alvarez, PJJ (reprint author), Univ Iowa, Dept Civil & Environm Engn, 4119 Seamans Ctr, Iowa City, IA 52245 USA. EM pedro-alvarez@uiowa.edu NR 25 TC 49 Z9 51 U1 1 U2 8 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD DEC PY 2002 VL 21 IS 12 BP 2631 EP 2639 DI 10.1897/1551-5028(2002)021<2631:EOEAMT>2.0.CO;2 PG 9 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 616XE UT WOS:000179328100015 PM 12463558 ER PT J AU Singh, SM Steinberg-Neifach, O Mian, IS Lue, NF AF Singh, SM Steinberg-Neifach, O Mian, IS Lue, NF TI Analysis of telomerase in Candida albicans: Potential role in telomere end protection SO EUKARYOTIC CELL LA English DT Article ID REVERSE-TRANSCRIPTASE; YEAST TELOMERASE; TETRAHYMENA TELOMERASE; SACCHAROMYCES-CEREVISIAE; CATALYTIC SUBUNIT; HUMAN-CELLS; IN-VITRO; MAMMALIAN TELOMERASE; SECONDARY STRUCTURE; NEGATIVE REGULATION AB Telomerase is a ribonucleoprotein reverse transcriptase responsible for the maintenance of one strand of telomere terminal repeats. Analysis of the telomerase complex in the budding yeast Saccharomyces cerevisiae has revealed the presence of one catalytic protein subunit (Est2p/TERT) and at least two noncatalytic components (Est1p and Est3p). The genome of the pathogenic yeast Candida albicans contains putative orthologues of all three, telomerase components. Disruption of each homologue resulted in significant but distinct telomere dysfunction in Candida. Similar to S. cerevisiae, the Candida EST3 disruption strain exhibits progressive telomere loss over many generations, at a rate that is consistent with incomplete replication. In contrast, telomeres in both the Candida TERT and EST1 disruption strains can contract rapidly, followed by partial or nearly complete recovery, suggesting a defect in telomere "capping." We propose that these two telomerase subunits may participate in the protection of chromosomal ends in Candida. Analysis of telomerase-mediated primer extension in vitro indicates that only the TERT protein is absolutely essential for enzyme activity. Our results support the conservation of telomerase protein components beyond the catalytic subunit but reveal species-specific phenotypic alterations in response to loss of individual telomerase component. We also identify potential homologues of Est1p in phylogenetically diverse organisms. The Est1p sequence family possesses a conserved N-terminal domain predicted to be structurally related to tetratricopeptide repeat-containing proteins. C1 Cornell Univ, Weill Med Coll, WR Hearst Microbiol Res Ctr, Dept Microbiol & Immunol, New York, NY 10021 USA. Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Lue, NF (reprint author), Cornell Univ, Weill Med Coll, WR Hearst Microbiol Res Ctr, Dept Microbiol & Immunol, 1300 York Ave, New York, NY 10021 USA. NR 61 TC 32 Z9 37 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 1535-9778 J9 EUKARYOT CELL JI Eukaryot. Cell PD DEC PY 2002 VL 1 IS 6 BP 967 EP 977 DI 10.1128/EC.1.6.967-977.2002 PG 11 WC Microbiology; Mycology SC Microbiology; Mycology GA 623UX UT WOS:000179722200013 PM 12477797 ER PT J AU Volkow, ND Fowler, JS Wang, GJ Ding, YS Gatley, SJ AF Volkow, ND Fowler, JS Wang, GJ Ding, YS Gatley, SJ TI Role of dopamine in the therapeutic and reinforcing effects of methylphenidate in humans: results from imaging studies SO EUROPEAN NEUROPSYCHOPHARMACOLOGY LA English DT Article; Proceedings Paper CT 3rd ECNP Workshop on Brain Imaging and Neuropsychopharmacology CY MAR 15-17, 2002 CL NICE, FRANCE SP ECNP DE ritalin; PET; stimulants; cocaine; routes of administration; pharmacokinetics; abuse ID DEFICIT HYPERACTIVITY DISORDER; NUCLEUS-ACCUMBENS; HUMAN BRAIN; INTRAVENOUS METHYLPHENIDATE; EXTRACELLULAR DOPAMINE; COCAINE REINFORCEMENT; THREO-METHYLPHENIDATE; ORAL METHYLPHENIDATE; D-2 RECEPTORS; TRANSPORTER AB Methylphenidate is the most commonly prescribed drug for the treatment of ADHD. We have used positron emission tomography to assess the role that methylphenidate's effects in brain dopamine have on its therapeutic and reinforcing effects. We have documented that in the human brain therapeutic doses of methylphenidate block more than 50% of the dopamine transporters and significantly enhance extracellular DA, an effect that appears to be modulated by the rate of DA release. Thus, we postulate that methylphenidate's therapeutic effects are in part due to amplification of DA signals, that variability in responses is in part due to differences in DA tone and that methylphenidate's effects are context dependent. Methylphenidate-induced increases in DA are also associated with its reinforcing effects but only when this occurs rapidly, as with intravenous administration. Moreover, abuse of methylphenidate is constrained by its long half-life, which we postulate limits the frequency at which it can be administered. (C) 2002 Elsevier Science B.V./ECNP All rights reserved. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. FU NIDA NIH HHS [DA 06891, DA 09490, DA 06278] NR 74 TC 123 Z9 125 U1 2 U2 16 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-977X J9 EUR NEUROPSYCHOPHARM JI Eur. Neuropsychopharmacol. PD DEC PY 2002 VL 12 IS 6 BP 557 EP 566 AR PII S0924-977X(02)00104-9 DI 10.1016/S0924-977X(02)00104-9 PG 10 WC Clinical Neurology; Neurosciences; Pharmacology & Pharmacy; Psychiatry SC Neurosciences & Neurology; Pharmacology & Pharmacy; Psychiatry GA 627EC UT WOS:000179919200007 PM 12468018 ER PT J AU Schowasser, G Hubel, H Hagemann, GB Amro, H Clark, RM Cromaz, M Diamond, RM Fallon, P Herskind, B Lane, G Ma, WC Macchiavelli, AO Odegard, SW Sletten, G Ward, D Wilson, JN AF Schowasser, G Hubel, H Hagemann, GB Amro, H Clark, RM Cromaz, M Diamond, RM Fallon, P Herskind, B Lane, G Ma, WC Macchiavelli, AO Odegard, SW Sletten, G Ward, D Wilson, JN TI Comparative quadrupole moments of triaxial superdeformed states in Lu-163,Lu-164,Lu-165 SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID LU-163; BANDS AB Average transition quadrupole moments in the yrast triaxial superdeformed bands of Lu-163, Lu-164 and Lu-165 were determined in a Doppler-shift attenuation-method experiment. Fractional Doppler shifts were determined in gamma-ray coincidence spectra measured with the Gammasphere array. The transition quadrupole moments derived from these data show a decrease from Lu-163 to Lu-165 which is not predicted by total-energy surface calculations. C1 Univ Bonn, Helmholtz Inst Strahlen & Kernphys, D-53115 Bonn, Germany. Niels Bohr Inst, DK-2100 Copenhagen O, Denmark. Mississippi State Univ, Mississippi State, MS 39762 USA. Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Oslo, Dept Phys, N-0316 Oslo, Norway. RP Univ Bonn, Helmholtz Inst Strahlen & Kernphys, Nussallee 14-16, D-53115 Bonn, Germany. EM schoenwa@iskp.uni-bonn.de RI Lane, Gregory/A-7570-2011 OI Lane, Gregory/0000-0003-2244-182X NR 20 TC 25 Z9 26 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6001 EI 1434-601X J9 EUR PHYS J A JI Eur. Phys. J. A PD DEC PY 2002 VL 15 IS 4 BP 435 EP 437 DI 10.1140/epja/i2002-10097-5 PG 3 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 643FA UT WOS:000180850200004 ER PT J AU Chung, SU Klempt, E Korner, JG AF Chung, SU Klempt, E Korner, JG TI SU(3) classification of p-wave eta pi and eta 'pi systems SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID EXOTIC MESON PRODUCTION; 18 GEV/C; ANNIHILATION; RESONANCE; REST AB An exotic meson, the pi(1)(1400) with J(PC) = 1(-+), has been seen to decay into a p-wave etapi system. If this decay conserves flavor SU(3), then it can be shown that this exotic meson must be a four-quark state (q (q) over bar + q (q) over bar) belonging to a flavor 10 circle plus (10) over bar representation of SU(3). In contrast, the pi(1)(1600) with a substantial decay mode into eta'pi is likely to be a member of a flavor octet. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Bonn, Helmholtz Inst Strahlen & Kernphys, D-53115 Bonn, Germany. Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RP Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM klempt@iskp.uni-bonn.de NR 21 TC 23 Z9 23 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6001 EI 1434-601X J9 EUR PHYS J A JI Eur. Phys. J. A PD DEC PY 2002 VL 15 IS 4 BP 539 EP 542 DI 10.1140/epja/i2002-10058-0 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 643FA UT WOS:000180850200018 ER PT J AU Chekanov, SV AF Chekanov, SV TI Uncertainties on the measurements of the top mass at a future e(+)e(-) collider SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID BOSE-EINSTEIN CORRELATIONS; QUARK MASS; COLOR RECONNECTION; E+E ANNIHILATION; W-MASS; SIMULATION; EVENTS AB The uncertainties due to limited knowledge of the multi-hadron final state on the measurements of the top mass at future linear colliders are discussed. This study is performed for e(+)e(-) --> t (t) over bar annihilation events at the center-of-mass energy of s(1/2) = 500 GeV using Monte Carlo models tuned to LEP experiments. The uncertainties are determined for the all-hadronic top-decay mode as well as for the lepton-plus-jets channel. C1 Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA. RP Argonne Natl Lab, HEP Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 37 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6044 EI 1434-6052 J9 EUR PHYS J C JI Eur. Phys. J. C PD DEC PY 2002 VL 26 IS 2 BP 173 EP 181 DI 10.1140/epjc/s2002-01048-7 PG 9 WC Physics, Particles & Fields SC Physics GA 638WV UT WOS:000180596200002 ER PT J AU Karkuszewski, ZP Sacha, K Smerzi, A AF Karkuszewski, ZP Sacha, K Smerzi, A TI Mean field loops versus quantum anti-crossing nets in trapped Bose-Einstein condensates SO EUROPEAN PHYSICAL JOURNAL D LA English DT Article ID COHERENT OSCILLATIONS; DOUBLE-WELL; GAS; INTERFERENCE; ARRAYS AB We study a Bose-Einstein condensate trapped in an asymmetric double well potential. Solutions of the time-independent Gross-Pitaevskii equation reveal intrinsic loops in the energy (or chemical potential) level behavior when the shape of the potential is varied. We investigate the corresponding behavior of the quantum (many-body) energy levels. Applying the two-mode approximation to the bosonic field operators, we show that the quantum energy levels create an anti-crossing net inside the region bounded by the loop of the mean field solution. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Jagiellonian Univ, Inst Fizyki, PL-30059 Krakow, Poland. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Karkuszewski, ZP (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Sacha, Krzysztof/L-3086-2013 OI Sacha, Krzysztof/0000-0001-6463-0659 NR 19 TC 21 Z9 21 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6060 J9 EUR PHYS J D JI Eur. Phys. J. D PD DEC PY 2002 VL 21 IS 3 BP 251 EP 254 DI 10.1140/epjd/e2002-00229-5 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 627NQ UT WOS:000179939500002 ER PT J AU Andiel, U Eidmann, K Hakel, P Mancini, RC Junkel-Vives, GC Abdallah, J Witte, K AF Andiel, U Eidmann, K Hakel, P Mancini, RC Junkel-Vives, GC Abdallah, J Witte, K TI Demonstration of aluminum K-shell line shifts in isochorically heated targets driven by ultrashort laser pulses SO EUROPHYSICS LETTERS LA English DT Article ID MULTIELECTRON IONS; DENSE-PLASMAS; PROFILES; HOT AB Targets consisting of 25 nm Al layers buried in solid carbon at depths of up to 400 nm have been irradiated with frequency doubled Ti:sapphire laser pulses of 150 fs duration at an intensity of a few 10(17) W/cm(2). The analysis of the emitted Al K-shell spectra yields densities close to that of solid Al and temperatures around 500 eV. By using the cold Si K-alpha line for wavelength calibration, the presence of a red dense-plasma line shift for several K-shell resonance and associated satellite lines is clearly demonstrated. C1 Max Planck Inst Quantum Opt, D-85748 Garching, Germany. Univ Nevada, Dept Phys, Reno, NV 89557 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Andiel, U (reprint author), Max Planck Inst Quantum Opt, D-85748 Garching, Germany. NR 27 TC 24 Z9 24 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD DEC PY 2002 VL 60 IS 6 BP 861 EP 867 DI 10.1209/epl/i2002-00297-5 PG 7 WC Physics, Multidisciplinary SC Physics GA 622DA UT WOS:000179630200008 ER PT J AU Gardner, SN Agrawal, AA AF Gardner, SN Agrawal, AA TI Induced plant defence and the evolution of counter-defences in herbivores SO EVOLUTIONARY ECOLOGY RESEARCH LA English DT Article DE evolution of resistance; induced versus constitutive defence; major gene resistance; phenotypic plasticity; plant-insect interactions; quantitative characters ID PHYTOPHAGOUS INSECT POPULATIONS; TETRANYCHUS-URTICAE KOCH; HOST-RANGE EVOLUTION; INDUCED RESISTANCE; NATURAL-SELECTION; ADAPTATION; GENETICS; COEVOLUTION; FITNESS; ECOLOGY AB We examine how induced plant defences affect the evolution of resistance in herbivores (i.e. the ability to overcome plant defences) compared with constitutive defence strategies. Since resistance of herbivores may evolve as a result of major monogenic and/or quantitative (polygenic or gene amplification) genetic sources, and the selective pressure imposed by plant defences affects the rate of evolution of each genetic source of resistance, we incorporate both into a model of herbivore evolution. We combine Mendelian single-locus and quantitative genetic models with a logistic population growth model based on an empirical plant-herbivore system. Induced defences may delay the evolution of both quantitative and major gene resistance and thus depress herbivore population size for more than 50 herbivore generations longer than constitutive defences. This increased longevity in the effectiveness of plant defence is associated with the production of substantially less plant defence over the long term, hence maximizing the benefit to cost ratio from the plant's perspective. C1 Univ Toronto, Dept Bot, Toronto, ON M5S 3B2, Canada. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Agrawal, AA (reprint author), Univ Toronto, Dept Bot, 25 Willcocks St, Toronto, ON M5S 3B2, Canada. NR 46 TC 19 Z9 20 U1 8 U2 30 PU EVOLUTIONARY ECOLOGY LTD PI TUCSON PA UNIV ARIZONA, 321 BIOSCIENCES WEST, TUCSON, AZ 85721 USA SN 1522-0613 J9 EVOL ECOL RES JI Evol. Ecol. Res. PD DEC PY 2002 VL 4 IS 8 BP 1131 EP 1151 PG 21 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 624KH UT WOS:000179758500003 ER PT J AU Eberling, JL Pivirotto, P Bringas, J Steiner, JP Kordower, JH Chu, YP Emborg, ME Bankiewicz, KS AF Eberling, JL Pivirotto, P Bringas, J Steiner, JP Kordower, JH Chu, YP Emborg, ME Bankiewicz, KS TI The immunophilin ligand GPI-1046 does not have neuroregenerative effects in MPTP-treated monkeys SO EXPERIMENTAL NEUROLOGY LA English DT Article DE GPI-1046; immunophilin; regeneration; MPTP; Parkinson's disease; SPECT; dopamine transporter ID DOPAMINE TRANSPORTER LOSS; BETA-CIT BINDING; PARKINSONS-DISEASE; SUBSTANTIA-NIGRA; CLINICAL CHANGES; IN-VIVO; CELLS; SPECT; FRACTIONATOR; DISECTOR AB Nonimmunosuppressant immunophilin ligands have been shown to have neurotrophic properties in rodent models of Parkinson's disease (PD), although little is known about the effects of these ligands in primates. The immunophilin ligand, GPI-1046, promotes the regeneration of dopamine (DA) cells in association with functional recovery in rodent models. We explored. the regenerative effects of GPI-1046 in an MPTP primate model of PD. We used single photon emission computed tomography,(SPECT) and the DA, transporter tracer (DAT), [I-123]beta-CIT, to evaluate DAT density and clinical recovery before and after treatment with GPI-1046 or vehicle. Subsequent histological studies were also performed. No effects of GPI-1046 were found on any of these measures. These findings show that GPI-1046 does not have regenerative effects in MPTP-treated primates and suggest that there may be species differences with respect to the trophic effects of GPI-1046 on nigrostriatal DA neurons. (C) 2002 Elsevier Science (USA). C1 Univ Calif Davis, Dept Neurol, Davis, CA 95616 USA. Univ Calif Davis, Ctr Neurosci, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Univ Calif San Francisco, Dept Neurosurg, San Francisco, CA 94103 USA. Guilford Pharmaceut Inc, Baltimore, MD 21224 USA. Rush Presbyterian St Lukes Med Ctr, Dept Neurol Sci, Chicago, IL 60612 USA. Rush Presbyterian St Lukes Med Ctr, Res Ctr Brain Repair, Chicago, IL 60612 USA. RP Eberling, JL (reprint author), Univ Calif Davis, Dept Neurol, Davis, CA 95616 USA. NR 26 TC 11 Z9 13 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0014-4886 J9 EXP NEUROL JI Exp. Neurol. PD DEC PY 2002 VL 178 IS 2 BP 236 EP 242 DI 10.1006/exnr.2002.8023 PG 7 WC Neurosciences SC Neurosciences & Neurology GA 628HX UT WOS:000179988500008 PM 12504882 ER PT J AU Greene, GA Finfrock, CC AF Greene, GA Finfrock, CC TI Measurements of the specific heat of high-purity copper at temperatures below 8 K by a modified pulse-heating technique SO EXPERIMENTAL THERMAL AND FLUID SCIENCE LA English DT Article DE copper; cryogenic; specific heat; electric pulse; liquid helium AB A precision calorimeter was used to measure the energy deposited in a liquid-helium-cooled copper target as a result of scattered nuclear radiation from an accelerator target in order to simulate the thermal response of a superconducting magnet under such conditions. The methodology selected for the accelerator application was to measure precisely the temperature rise of a copper target in a vacuum, and to convert the results into energy deposition using the specific heat. Therefore, precise measurements of the specific heat of the copper target were necessary to achieve the required precision and accuracy in the energy deposition measurements for the accelerator application. A pulse-heating technique to measure the specific heat was developed in which electrical square waves were delivered to a surface-mounted heater on the copper target, and the temperature rise of the copper target was measured. The specific heat of the copper was measured from 6 to 8 K and compared to data in the literature. The data were also used to infer the electronic- and lattice-specific-heat coefficients and the Debye temperature for the copper that was used. Comparisons of the data to the specific heat and specific-heat coefficients in the literature are presented. The present technique is shown to be useful for the measurement of the specific heat of good thermal conductors, especially metals at cryogenic temperatures, when very high precision is required. (C) 2002 Elsevier Science Inc. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Greene, GA (reprint author), Brookhaven Natl Lab, Bldg 703, Upton, NY 11973 USA. NR 10 TC 1 Z9 1 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0894-1777 J9 EXP THERM FLUID SCI JI Exp. Therm. Fluid Sci. PD DEC PY 2002 VL 27 IS 1 BP 111 EP 119 AR PII S0894-1777(02)00218-2 DI 10.1016/S0894-1777(02)00218-2 PG 9 WC Thermodynamics; Engineering, Mechanical; Physics, Fluids & Plasmas SC Thermodynamics; Engineering; Physics GA 623UN UT WOS:000179721400009 ER PT J AU Novaro, V Pustovrh, C Colman-Lerner, A Radisky, D Lo Nostro, F Paz, D Jawerbaum, A Gonzalez, E AF Novaro, V Pustovrh, C Colman-Lerner, A Radisky, D Lo Nostro, F Paz, D Jawerbaum, A Gonzalez, E TI Nitric oxide induces gelatinase A (matrix metalloproteinase 2) during rat embryo implantation SO FERTILITY AND STERILITY LA English DT Article DE decidualization; maternal-embryo interaction; pregnancy; rat uterus ID ENDOMETRIAL STROMAL CELLS; NECROSIS-FACTOR-ALPHA; MOUSE UTERUS; PERIIMPLANTATION PERIOD; TISSUE INHIBITORS; IN-VITRO; EXPRESSION; SYNTHASE; DECIDUALIZATION; PREECLAMPSIA AB Objective: To evaluate a reciprocal signaling interaction initiated by embryo-derived nitric oxide (NO) to facilitate implantation by increased production of gelatinase A (matrix metalloproteinase 2, MMP2) in uterine stroma. Design: Experimental animal studies. Setting: Reproductive-physiology research laboratory. Animal(s): Female syngeneic Wistar rats aged 14 weeks. Intervention(s): Vaginal smears to confirm pregnancy. Oviductal ligature to avoid the descent of blastocysts to the uterine lumen. Plasma exudation assays to locate uterine blastocyst implantation sites. Organ cultures treated with NO donors and nitric oxide synthase (NOS) inhibitors. Main Outcome Measure(s): Expression of MMP2 and NO was assessed by Western blot and zymography of tissue extracts and by immunofluorescence of tissue sections. Result(s): An increase in MMP2 activity was found in uterine extracts in early pregnant rats and was concentrated at implantation sites. Immunolocalization experiments showed that inducible NOS was expressed on the surface of the implanting blastocyst adjacent to the uterine epithelium at the sites of increased MMP2 expression. In organ culture experiments, NO donors were found to increase, whereas NOS inhibitors were found to decrease MMP2 activity in uterine tissue sections. Conclusion(s): Blastocyst-derived NO contributes to the production of uterine-derived MMP2, an essential component of implantation and initiation of placentation. C1 Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. Ctr Estudios Farmacol & Bot, Buenos Aires, DF, Argentina. Inst Mol Sci, Berkeley, CA USA. Ciudad Univ, Buenos Aires, DF, Argentina. RP Novaro, V (reprint author), Lawrence Berkeley Natl Lab, Div Life Sci, 1 Cyclotron Rd,83-101, Berkeley, CA 94720 USA. OI Colman-Lerner, Alejandro A/0000-0002-2557-8883 NR 43 TC 28 Z9 31 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0015-0282 J9 FERTIL STERIL JI Fertil. Steril. PD DEC PY 2002 VL 78 IS 6 BP 1278 EP 1287 AR PII S0015-0282(02)04240-1 DI 10.1016/S0015-0282(02)04240-1 PG 10 WC Obstetrics & Gynecology; Reproductive Biology SC Obstetrics & Gynecology; Reproductive Biology GA 625VX UT WOS:000179837200024 PM 12477525 ER PT J AU Gardner, TH Berry, DA Lyons, KD Beer, SK Freed, AD AF Gardner, TH Berry, DA Lyons, KD Beer, SK Freed, AD TI Fuel processor integrated H2S catalytic partial oxidation technology for sulfur removal in fuel cell power plants SO FUEL LA English DT Article; Proceedings Paper CT 22nd ACS National Meeting CY AUG 26-30, 2001 CL CHICAGO, ILLINOIS SP ACS DE desulfurization; hydrogen sulfide catalytic oxidation; fuel cells ID HYDROGEN-SULFIDE; NATURAL-GAS; ACTIVATED CARBON; MECHANISM; KINETICS AB H2S catalytic partial oxidation technology with an activated carbon catalyst was found to be a promising method for the removal of hydrogen sulfide from fuel cell hydrocarbon feedstocks. Three different fuel cell feedstocks were considered for analysis: sour natural gas, sour effluent from a liquid middle distillate fuel processor and a Texaco O-2-blown coal-derived synthesis gas. The H2S catalytic partial oxidation reaction, its integratability into fuel cell power plants with different hydrocarbon feedstocks and its salient features are discussed. Experimental results indicate that H2S concentration can be removed down to the part-per-million level in these plants. Additionally, a power law rate expression was developed and reaction kinetics compared to prior literature. The activation energy for this reaction was determined to be 34.4 kJ/g mol with the reaction being first order in H2S and 0.3 order in O-2. (C) 2002 Elsevier Science Ltd. All rights reserved. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26505 USA. REM Engn Serv, Morgantown, WV 26505 USA. RP Gardner, TH (reprint author), US DOE, Natl Energy Technol Lab, POB 880,3610 Collins Ferry Rd, Morgantown, WV 26505 USA. NR 18 TC 29 Z9 31 U1 0 U2 12 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0016-2361 J9 FUEL JI Fuel PD DEC PY 2002 VL 81 IS 17 BP 2157 EP 2166 AR PII S0016-2361(02)00161-8 DI 10.1016/S0016-2361(02)00161-8 PG 10 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 600WF UT WOS:000178414200003 ER PT J AU Allison, VJ AF Allison, VJ TI Nutrients, arbuscular mycorrhizas and competition interact to influence seed production and germination success in Achillea millefolium SO FUNCTIONAL ECOLOGY LA English DT Article DE biomass; fitness; maternal environment; path analysis; tissue nutrient concentrations ID PATH-ANALYSIS; PLANTS; REPRODUCTION; GROWTH; FIELD; VARIABILITY; ASTERACEAE; MATURATION; INFECTION; SYMBIOSIS AB 1. Environmental variables that positively affect one aspect of plant fitness, may have no effect, or even negatively affect some other component of fitness. 2. Using individuals of Achillea millefolium grown under field conditions in Michigan, USA, the hypothesis was tested that seed number was determined largely by plant biomass, while seed germination success depends on tissue nutrient concentrations. The impact was assessed of four biotic and abiotic factors on seed number and germination success: root competition, shoot competition, fertilizer, and removal of fungi by fungicide application. 3. Using a path analysis, it was found that total plant biomass positively affected both seed number and germination success, while inclusion of other variables did not greatly affect the amount of variation the model was able to explain. Fertilizer and fungicide increased, while root and shoot competition decreased both seed number and germination. 4. Fungicide applied to the maternal plant increased biomass but decreased tissue phosphorus concentrations. In species where germination responds to nutrient concentrations, the potential exists for opposing impacts of environmental treatments on different components of fitness. 5. This study suggests that environmental impacts on seed number will outweigh impacts on germination success under field conditions, and that biomass is an adequate surrogate for fitness in herbaceous plants. C1 Univ Michigan, Dept Ecol & Evolutionary Biol, Ann Arbor, MI 48109 USA. RP Allison, VJ (reprint author), Argonne Natl Lab, Div Environm Res, Bldg 203,E-133,9700 S Cass Ave, Argonne, IL 60647 USA. NR 34 TC 16 Z9 17 U1 1 U2 26 PU BLACKWELL PUBLISHING LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0269-8463 J9 FUNCT ECOL JI Funct. Ecol. PD DEC PY 2002 VL 16 IS 6 BP 742 EP 749 DI 10.1046/j.1365-2435.2002.00675.x PG 8 WC Ecology SC Environmental Sciences & Ecology GA 625EF UT WOS:000179803400005 ER PT J AU Thome, RJ Heitzenroeder, PJ AF Thome, RJ Heitzenroeder, PJ CA FIRE Design Team TI Engineering overview of the fusion ignition research experiment (FIRE) SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE FIRE; TF coils; bucked and wedged design AB The FIRE tokamak is an option for the next step in the U.S. magnetic fusion energy program. The design goals have evolved to a major radius of 2.14 m, minor radius of 0.525 m, toroidal field (TF) of 10 T and plasma current of 7.7 mA for a flat-top time of similar to20 s. The requirement for 3000 full-power, full-field pulses and 30,000 pulses at 2/3 of full field has been retained since 1999. All magnets are inertially cooled with liquid nitrogen. Design options have been considered over a range of parameter space for either a wedged TF coil structure or a bucked and wedged TF/Central Solenoid structure. The wedged configuration has been selected as the baseline. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Gen Atom, San Diego, CA 92121 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Thome, RJ (reprint author), Gen Atom, 3550 Gen Atom Ct, San Diego, CA 92121 USA. EM thomer@gat.com NR 3 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 53 EP 57 AR PII S0920-3796(02)00207-7 DI 10.1016/S0920-3796(02)00207-7 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300007 ER PT J AU Sharpe, JP Petti, DA Bartels, HW AF Sharpe, JP Petti, DA Bartels, HW TI A review of dust in fusion devices: Implications for safety and operational performance SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE tokamak dust; safety analysis; fusion aerosols; plasma-surface interaction ID TORE-SUPRA; TOKAMAK; PLASMA; PARTICULATE; PARTICLES AB Dust is produced in fusion devices by energetic plasma-surface interactions. As the amount of dust increases, potential safety and operational concerns arise. The dust may contain tritium, may be radioactive from activation products, and may be chemically reactive and/or toxic. Possible accidents in large fusion reactors could mobilize the dust and threaten public safety. Dust also poses potential problems to device operation. For example, plasma startup could be impeded, particulate injected from flaking deposits may disrupt the fusion plasma, and tritium retention in dust will affect fuel recovery systems. The current understanding of dust's role in fusion devices is reviewed in this paper by discussing mechanisms of dust production, considering ways dust impacts device safety and operation, and comparing characteristics of dust collected from existing fusion plasma research devices. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID 83415 USA. IPP Garching, ITER Int Team, Garching, Germany. RP Sharpe, JP (reprint author), Idaho Natl Engn & Environm Lab, Fus Safety Program, POB 1625,MS 3860, Idaho Falls, ID 83415 USA. EM sharjp@inel.gov NR 23 TC 113 Z9 116 U1 0 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 153 EP 163 AR PII S0920-3796(02)00191-6 DI 10.1016/S0920-3796(02)00191-6 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300021 ER PT J AU Marshall, T AF Marshall, T TI Safety implications of an integrated boiling curve model for water-cooled divertor channels SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE boiling curve; CHF; finite element modeling; post-CHF; thermal ID FLOW AB The international fusion community is actively researching advanced heat transfer methods for removal of high thermal loads from next-generation divertor assemblies. Such advanced techniques may indeed optimize the operational and economical performance of future divertor designs. However, with its extensive operational database, water-cooling remains as one of the optimum choices for near-term divertor designs. Critical heat flux (CHF) is the maximum heat flux that water, at a given set of inlet conditions, can remove via fully developed nucleate boiling. Accordingly, an accurate CHF calculation is of the utmost importance for maintaining adequate safety margins in divertor operation. This paper uses the integrated boiling curve model developed at Sandia National Laboratories to examine the safety implications of calculating the CHF. In particular, this paper focuses on the influence of the finite element peaking factor (FEPF) that converts the heat flux predicted by CHF correlations into a plasma heat flux that can be measured. The analyses illustrate that the FEPF is proportional to the plasma heat flux and thus accurate calculation of the CHF requires the use of the appropriate FEPF for the given water conditions and plasma heat flux. It is shown that using a geometric peaking factor is inadequate since the true peak factor is dependent upon. the plasma heat flux. The conclusion is that a finite element analysis incorporating an integrated boiling curve is required for accurate calculation of the CHF. (C) 2002 Elsevier Science B.V. All rights reserved. C1 INEEL Fus Safety Program, Idaho Falls, ID 83415 USA. RP Marshall, T (reprint author), INEEL Fus Safety Program, POB 1625, Idaho Falls, ID 83415 USA. NR 14 TC 1 Z9 1 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 235 EP 242 AR PII S0920-3796(02)00246-6 DI 10.1016/S0920-3796(02)00246-6 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300033 ER PT J AU Marshall, T Porfiri, MT Topilski, L Merrill, B AF Marshall, T Porfiri, MT Topilski, L Merrill, B TI Fusion safety codes: international modeling with MELCOR and ATHENA-INTRA SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE safety codes; MELCOR; ATHENA; ICE; coolant ingress; condensation ID COOLANT EVENT; INGRESS AB For a number of years, the world fusion safety community has been involved in benchmarking their safety analyses codes against experiment data to support regulatory approval of a next step fusion device. This paper discusses the benchmarking of two prominent fusion safety thermal-hydraulic computer codes. The MELCOR code was developed in the US for fission severe accident safety analyses and has been modified for fusion safety analyses. The ATHENA code is a multifluid version of the US-developed RELAP5 code that is also widely used for fusion safety analyses. The ENEA Fusion Division uses ATHENA in conjunction with the INTRA code for its safety analyses. The INTRA code was developed in Germany and predicts containment building pressures, temperatures and fluid flow. ENEA employs the French-developed ISAS system to couple ATHENA and INTRA. This paper provides a brief introduction of the MELCOR and ATHENA-INTRA codes and presents their modeling results for the following breaches of a water cooling line into the tokamak vacuum vessel, (1) water injection in vacuum with condensation of the flashed steam and (2) water injection in vacuum. The modeling predictions are compared with experimental results from the ingress-of-coolant event (ICE) facility in Japan. It is observed that the codes' predictions exhibit good agreement with the experiment data, which suggests that the codes include the proper physical mechanisms associated with the chosen accident scenarios. It is thereby concluded that either of the codes can be used to model the defined transient. (C) 2002 Elsevier Science B.V. All rights reserved. C1 INEEL Fus Safety Program, Idaho Falls, ID 83415 USA. EURATOM, ENEA, Fus Div, Ctr Ric Frascati, I-00044 Frascati, Italy. ITER, Garching Joint Work Site, D-85748 Garching, Germany. RP Marshall, T (reprint author), INEEL Fus Safety Program, POB 1625, Idaho Falls, ID 83415 USA. EM marstd@incl.gov NR 12 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 243 EP 249 AR PII S0920-3796(02)00249-1 DI 10.1016/S0920-3796(02)00249-1 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300034 ER PT J AU Reyes, S Sanz, J Latkowski, JF AF Reyes, S Sanz, J Latkowski, JF TI Use of clearance indexes to assess waste disposal issues for the HYLIFE-II inertial fusion energy power plant design SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE inertial fusion energy; safety; environment AB Traditionally, waste management studies for fusion energy have used the waste disposal rating (WDR) to evaluate if radioactive material from irradiated structures could qualify for shallow land burial. However, given the space limitations and the negative public perception of large volumes of waste, there is a growing international motivation to develop a fusion waste management system that maximizes the amount of material that can be cleared or recycled. In this work, we present an updated assessment of the waste management options for the HYLIFE-II inertial fusion energy (IFE) power plant, using the concept of clearance index (0) for radioactive waste disposal. With that purpose, we have performed a detailed neutronics analysis of the HYLIFE-II design, using the TART and ACAB computer codes for neutron transport and activation, respectively. Whereas the traditional version Of ACAB only provided the user with the gamma contact dose rate for recycling assessments and WDR as an index for waste disposal considerations, here we have modified the code to calculate CIs using the current international atomic energy agency (IAEA) clearance limits for radiological waste disposal. The results from the analysis are used to perform an assessment of the waste management options for the HYLIFE-II IFE design. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Nacl Educ Distancia, ETSII, Dept Ingn Energet, E-28040 Madrid, Spain. Inst Fus Nucl, Madrid, Spain. RP Reyes, S (reprint author), Lawrence Livermore Natl Lab, POB 808,L-641, Livermore, CA 94550 USA. EM reyessuarez1@llnl.gov NR 14 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 257 EP 261 AR PII S0920-3796(02)00187-4 DI 10.1016/S0920-3796(02)00187-4 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300036 ER PT J AU Merrill, BJ Sze, DK Khater, HY Mogahed, EA AF Merrill, BJ Sze, DK Khater, HY Mogahed, EA TI Safety implications of CLiFF liquid metal first walls SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE fusion safety; LOVA; CliFF; site dose; liquid metal first walls; lithium fire ID FUSION AB In this article we explore some of the safety issues associated with the Advanced Power Extraction (APEX) liquid metal first wall (FW) concept called the Convective Liquid Flow First Wall (CLiFF) design. In particular, we examine the chemical reactivity of and site boundary dose from three liquid metals being proposed for the CUFF FW during a worst case confinement-boundary-bypass accident. The liquid metals considered are: lithium, tin, and gallium. The accident analyzed is a loss-of-vacuum accident (LOVA), during which air enters the CUFF vacuum vessel (VV) from an adjoining room through a connecting diagnostic port or plasma-heating duct. The resulting lithium fire was analyzed and the energy released from this fire was found to be manageable for the CUFF blanket design presently under consideration. The estimated dose at the site boundary is less than the no-evacuation limit of 10 mSv for ground level releases if plant isolation occurs within several hours. (C) 2002 Published by Elsevier Science B.V. C1 INEEL Fus Safety Program, Idaho Falls, ID 83415 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Merrill, BJ (reprint author), INEEL Fus Safety Program, POB 1625, Idaho Falls, ID 83415 USA. EM bdm@inel.gov NR 20 TC 5 Z9 5 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 285 EP 293 AR PII S0920-3796(02)00254-5 DI 10.1016/S0920-3796(02)00254-5 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300040 ER PT J AU Cadwallader, LC AF Cadwallader, LC TI Electrical power distribution system operating experience review for fusion applications SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE failure rate data; electrical equipment; initiating event frequencies AB This paper describes safety research on electrical distribution systems applicable to fusion facilities. Electrical power has many uses in both magnetic and inertial fusion experiments; it is the most important support system for any fusion experiment. Electricity powers a wide variety of plant equipment, including vacuum pumps, magnets, coolant pumps, air handlers, compressors, and either plasma heating or target implosion drivers. Electricity also powers instrumentation and controls, control and data acquisition computers, accident mitigation systems and site security systems. Most facilities use electrical power to ensure adequate confinement of radioactive materials via air pressure zone control, valve isolation, and operation of cleanup systems. As a result, operating experiences of electrical switchgear, cabling, motor control centers, and electrical panels have been examined for reliability, maintenance times, accident case histories, accident initiating event frequencies, and personnel safety issues, Electrical component failure rates and repair times, and initiating event frequencies are presented in this paper. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID 83415 USA. RP Cadwallader, LC (reprint author), Idaho Natl Engn & Environm Lab, Fus Safety Program, POB 1625, Idaho Falls, ID 83415 USA. EM lcc@inel.gov RI Cadwallader, Lee/F-6933-2014 NR 9 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 327 EP 331 AR PII S0920-3796(02)00123-0 DI 10.1016/S0920-3796(02)00123-0 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300045 ER PT J AU Xu, ZY Reed, CB Pan, CJ AF Xu, ZY Reed, CB Pan, CJ TI Surface and bulk MHD instabilities due to insulator coating imperfections SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE insulator coating imperfections; MHD; electric potential ID FLOW AB Experiments were performed using copper electrodes inserted into the wall of a perfectly insulated duct to simulate insulator coating flaking or cracking. The results show that surface electric potential U and MHD pressure drop AP exhibit a non-monotonic behavior with increasing V(0), while the magnetic field B(0) is held constant. Additional experiments were also performed keeping all external experimental conditions fixed while measuring the change of U, V(0), B(0), and DeltaP with increasing time. It was found that while all external experimental conditions were kept constant, the system changed by itself and U, V(0) and DeltaP exhibited a non-monotonic behavior with increasing time. The results seem contrary to the law of DeltaP proportional to V(0)B(0)(n), but are consistent with conservation of energy, which implies that the change is due to some inherent feature of the system, or possibly instabilities, which may occur due to insulator coating imperfections. (C) 2002 Elsevier Science B.V. All rights reserved. C1 SW Inst Phys, Chengdu 610041, Sichuan, Peoples R China. Argonne Natl Lab, Argonne, IL 60439 USA. RP Xu, ZY (reprint author), SW Inst Phys, POB 432, Chengdu 610041, Sichuan, Peoples R China. EM xuzy@swip.ac.cn; cbreed@anl.gov NR 10 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 375 EP 381 AR PII S0920-3796(02)00267-3 DI 10.1016/S0920-3796(02)00267-3 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300051 ER PT J AU Moore, RL Merrill, BJ AF Moore, RL Merrill, BJ TI Comparison of ATHENA/RELAP results against ice experimental data SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE computer codes; condensation heat transfer; experimental results; ICE; MELCOR; validation AB In order to demonstrate the adequacy of the International Thermonuclear Experimental Reactor design from a safety stand point as well as investigating the behavior of two-phase flow phenomena during an ingress of coolant event, an integrated ICE test facility was constructed in Japan. The data generated from the ICE facility offers a valuable means to validate computer codes such as ATHENA/RELAP5, which is one of the codes used at the Idaho National Engineering And Environmental Laboratory (INEEL) to evaluate the safety of various fusion reactor concepts. In this paper we compared numerical results generated by the ATHENA code with corresponding test data from the ICE facility. Overall we found good agreement between the test data and the predicted results. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID USA. RP Moore, RL (reprint author), Idaho Natl Engn & Environm Lab, Fus Safety Program, Idaho Falls, ID USA. EM rmm@inel.gov NR 8 TC 2 Z9 2 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 411 EP 419 AR PII S0920-3796(02)00284-3 DI 10.1016/S0920-3796(02)00284-3 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300056 ER PT J AU Chang, GS Ambrosek, RG Ingram, FW AF Chang, GS Ambrosek, RG Ingram, FW TI ATR Al-B neutron filter design for fusion material experiment SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE Al-B neutron filter design; Advanced Test Reactor; fusion material experiment AB Ferritic steels, vanadium alloys, and ceramics are being developed for potential use in fusion reactors. Properties of these materials after irradiation are required for evaluation of their acceptability. The Irradiation Test Vehicle (ITV) was installed in the Advanced Test Reactor (ATR) center flux trap position for irradiation of materials. The ratio of fast to thermal neutron flux is low when compared to a fusion reactor. In this study, one of the chosen materials for potential testing is a vanadium alloy. The test assembly design goals are vanadium (V-Li bond) specimen displacement per atom (dpa) greater than 10 dpa per year, and (51)V transmutation at 30 dpa less than 0.5 atom%. The dpa is proportional to and dominated by the fast neutron fluence (E > 0.1 Mev). The (51)V transmutation rate is proportional to and dominated by the thermal neutron fluence (E < 0.414 eV). To prevent excessive transmutation of the vanadium, the thermal neutron fluence needs to be limited while attaining the required dpa. A neutron filter to harden the neutron spectrum is required such that the design goals can be met. The computer codes MCNP and ORIGEN-2 were coupled by MCWO, and were utilized to design and evaluate a thermal neutron filter in the ATR ITV that provides an acceptable environment for vanadium alloy testing. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Chang, GS (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. EM gsc@inel.gov NR 4 TC 1 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 481 EP 485 AR PII S0920-3796(02)00133-3 DI 10.1016/S0920-3796(02)00133-3 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300066 ER PT J AU Swain, DW Carter, MD AF Swain, DW Carter, MD TI Plasma heating and current drive systems for the fusion ignition research experiment (FIRE) SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE FIRE; ion cyclotron; lower hybrid AB FIRE is a high-field, burning-plasma tokamak that is being studied as a possible option for future fusion research. Preliminary parameters for this machine are R(0) = 2.14 in, a = 0.595 in, B(0) = 10 T, and I(p) = 7.7 MA. Magnetic field coils are to be made of copper and pre-cooled with LN(2) before each shot. The flat-top pulse length desired is greater than or equal to 20 s. Ion cyclotron (IC) and lower hybrid rf systems will be used for heating and current drive. Present specifications call for 20 MW of IC heating power, with an additional 10 MW of IC power or 20 MW of lower hybrid power as upgrade options. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Swain, DW (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. EM swaindw@ornl.gov NR 6 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 541 EP 545 AR PII S0920-3796(02)00200-4 DI 10.1016/S0920-3796(02)00200-4 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300073 ER PT J AU Sawan, ME Khater, HY Zinkle, SJ AF Sawan, ME Khater, HY Zinkle, SJ TI Nuclear features of the fusion ignition research experiment (FIRE) SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE fusion ignition research experiment; nuclear heating; radiation damage; insulator dose ID COPPER-ALLOYS AB Critical issues were addressed and R&D needs were identified. Modest values of nuclear heating occur in the FIRE components. The total nuclear heating in the 16 TF coils during DT shots is 19 MW. The cumulative damage in the copper alloys used is very low ( < 0.05 dpa). However, issues of low temperature embrittlement and thermal creep at high temperatures need to be resolved by an R&D program. The radiation induced resistivity increase in the conductors of the TF coils is primarily due to displacement damage and is < 20% of the unirradiated resistivity. The magnet insulator development R&D program should involve irradiation to dose levels up to 1.5 x 10(10) Rad with the proper mix between neutrons and gamma photons (50% gamma dose) relevant to FIRE conditions. Low levels of activity and decay heat are obtained. Hands-on ex-vessel maintenance is feasible. All components qualify as Class C low-level waste. Activation of nitrogen gas inside the cryostat produces a very small amount of (13)N and (14)C. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Wisconsin, Fus Technol Inst, Madison, WI 53706 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sawan, ME (reprint author), Univ Wisconsin, Fus Technol Inst, 1500 Engn Dr, Madison, WI 53706 USA. EM sawan@engr.wisc.edu OI Zinkle, Steven/0000-0003-2890-6915 NR 19 TC 9 Z9 9 U1 1 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 547 EP 557 AR PII S0920-3796(02)00281-8 DI 10.1016/S0920-3796(02)00281-8 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300074 ER PT J AU Kessel, CE Meade, D Jardin, SC AF Kessel, CE Meade, D Jardin, SC TI Physics basis and simulation of burning plasma physics for the fusion ignition research experiment (FIRE) SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE plasma physics; fusion ignition research experiment (FIRE); ELMy H-mode ID H-MODE PEDESTAL; NEOCLASSICAL TEARING MODES; HYBRID CURRENT DRIVE; DIII-D TOKAMAK; HIGH-DENSITY; STABILIZATION; CONFINEMENT; DATABASE AB The FIRE design for a burning plasma experiment is described in terms of its physics basis and engineering features. Systems analysis indicates that the device has a wide operating space to accomplish its mission, both for the ELMy H-mode reference and the high bootstrap current/high-beta advanced tokamak regimes. Simulations with 1.5D transport codes reported here both confirm and constrain the systems projections. Experimental and theoretical results are used to establish the basis for successful burning plasma experiments in FIRE. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kessel, CE (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. EM ckessel@pppl.gov RI Jardin, Stephen/E-9392-2010 NR 30 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 559 EP 567 AR PII S0920-3796(02)00199-0 DI 10.1016/S0920-3796(02)00199-0 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300075 ER PT J AU Meier, WR Logan, BG Waldron, WL Sabbi, GL Callahan, DA Peterson, PF Goodin, DT AF Meier, WR Logan, BG Waldron, WL Sabbi, GL Callahan, DA Peterson, PF Goodin, DT TI Progress toward heavy-ion IFE SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE inertial fusion energy (IFE); heavy-ion fusion; IFE targets; IFE chambers ID POWER-PLANT DESIGN; DISTRIBUTED RADIATOR; TARGET FABRICATION; FUSION TARGET; HYLIFE-II; CHAMBERS; FACILITY; DRIVEN; BEAMS AB Successful development of heavy-ion fusion (HIF) will require scientific and technology advances in areas of targets, drivers and chambers. Design work on heavy-ion targets indicates that high gain (60-130) may be possible with a similar to 3-6 MJ driver depending on the ability to focus the beams to small spot sizes. Significant improvements have been made on key components of heavy-ion drivers, including sources, injectors, insulators and ferromagnetic materials for long-pulse induction accelerator cells, solid-state pulsers, and superconducting quadrupole magnets. The leading chamber concept for HIF is the thick-liquid-wall HYLIFE-II design, which uses an array of flibe jets to protect chamber structures from X-ray, debris, and neutron damage. Significant progress has been made in demonstrating the ability to create and control the types of flow needed to form the protective liquid blanket. Progress has also been made on neutron shielding for the final focus magnet arrays with predicted lifetimes now exceeding the life of the power plant. Safety analyses have been completed for the HYLIFE-II design using state-of-the-art codes. Work also continues on target fabrication and injection for HIF. A target injector experiment capable of > 5 Hz operation has been designed and construction will start in 2002. Methods for mass-production of hohlraum targets are being evaluated with small-scale experiments and analyses. Progress in these areas will be reviewed. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Meier, WR (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. EM meier5@llnl.gov NR 29 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 577 EP 585 AR PII S0920-3796(02)00273-9 DI 10.1016/S0920-3796(02)00273-9 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300077 ER PT J AU Raffray, AR Federici, G Hassanein, A Haynes, D AF Raffray, AR Federici, G Hassanein, A Haynes, D TI Dynamic chamber armor behavior in IFE and MFE SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE magnetic fusion energy; inertial fusion energy; armor materials ID PLASMA-FACING COMPONENTS; THERMAL RESPONSE; TRANSIENTS; SIMULATION; RACLETTE; MODEL; JET AB The chamber wall armor is subject to demanding conditions in both inertial fusion energy (IFE) and magnetic fusion energy (MFE) chambers. This paper assesses the requirements on armor imposed by the operating conditions in IFE and MFE, including energy deposition density, time of deposition and frequencies, and discusses their impact on the performance of the candidate armor materials. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Diego, La Jolla, CA 92093 USA. ITER Garching Joint Work Site, D-85748 Garching, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Wisconsin, Fus Technol Inst, Madison, WI 53706 USA. RP Raffray, AR (reprint author), Univ Calif San Diego, 458 EBU 2, La Jolla, CA 92093 USA. EM raffray@fusion.ucsd.edu NR 23 TC 12 Z9 12 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 597 EP 608 AR PII S0920-3796(02)00138-2 DI 10.1016/S0920-3796(02)00138-2 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300079 ER PT J AU Hassanein, A Morozov, V AF Hassanein, A Morozov, V TI Chamber wall response to target implosion in inertial fusion reactors: new and critical assessments SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE chamber walls; inertial fusion reactors; IFE systems ID PLASMA; DISRUPTIONS; STABILITY; BORON AB The chamber walls in inertial fusion energy (IFE) reactors are exposed to harsh conditions following each target implosion. Key issues of the cyclic IFE operation include intense photon and ion deposition, wall thermal and hydrodynamic evolution, wall erosion and fatigue lifetime, and chamber clearing and evacuation to ensure desirable conditions prior to next target implosion. Several methods for wall protection have been proposed in the past, each having its own advantages and disadvantages. These methods include use of solid bare walls, gas-filled cavities, and liquid walls/jets. Detailed models have been developed for reflected laser light, emitted photons, and target debris deposition and interaction with chamber components and have been implemented in the comprehensive HEIGHTS software package. The focus of this study is to critically assess the reliability and the dynamic response of chamber walls in IFE systems. Of particular concern is the effect on wall erosion lifetime due to various erosion mechanisms, such as vaporization, chemical and physical sputtering, melt/liquid splashing and explosive erosion, and fragmentation of liquid walls. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Hassanein, A (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM hassanein@anl.gov NR 21 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 609 EP 618 AR PII S0920-3796(02)00280-6 DI 10.1016/S0920-3796(02)00280-6 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300080 ER PT J AU Reyes, S Schmitt, RC Latkowski, JF Sanz, J AF Reyes, S Schmitt, RC Latkowski, JF Sanz, J TI Liquid wall options for tritium-lean fast ignition inertial fusion energy power plants SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 6th International Symposium on Fusion Nuclear Technology CY APR 07-12, 2002 CL SAN DIEGO, CA DE fast ignition; liquid wall chambers ID HYLIFE-II; DESIGN; FUELS AB In an inertial fusion energy (IFE) thick-liquid chamber design such as HYLIFE-II, a molten-salt is used to attenuate neutrons and protect the chamber structures from radiation damage. In the case of a fast ignition inertial fusion system, advanced targets have been proposed that may be self-sufficient in terms of tritium breeding (i.e. the amount of tritium bred in target exceeds the amount burned). This aspect allows for greater freedom when selecting a liquid for the protective blanket, given that lithium-bearing compounds are no longer required. Materials selection may now be based upon other characteristics, such as safety and environmental (S&E), pumping power, corrosion, and vapor pressure, along with others. The present work assesses the characteristics of many single, binary, and ternary molten-salts and liquid metals using the NIST Properties of Molten Salts Database. As an initial screening, liquids were evaluated for their S&E characteristics, which included an assessment of waste disposal rating (WDR), contact dose, and radioactive afterheat. Liquids that passed the S&E criteria were then evaluated for required pumping power. The pumping power was calculated using three components: velocity head losses, frictional losses, and lifting power. The results of the assessment are used to identify those materials that are suitable for potential liquid-chamber fast-ignition IFE concepts, from both the S&E and pumping power perspective. Recommendations for further analysis are also made. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Michigan, Dept Nucl Engn, Ann Arbor, MI 48109 USA. Univ Nacl Educ Distancia, Dpto Ingn Energet, ETSII, E-28040 Madrid, Spain. Inst Fus Nucl, Madrid, Spain. RP Reyes, S (reprint author), Lawrence Livermore Natl Lab, POB 808,Mailstop L-641, Livermore, CA 94550 USA. EM reyessuarez1@llnl.gov NR 13 TC 3 Z9 3 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD DEC PY 2002 VL 63-64 BP 635 EP 640 AR PII S0920-3796(02)00198-9 DI 10.1016/S0920-3796(02)00198-9 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 628LB UT WOS:000179995300083 ER PT J AU Liang, Q Nguyen, K Satyamurthy, N Barrio, JR Phelps, ME Gambhir, SS Herschman, HR AF Liang, Q Nguyen, K Satyamurthy, N Barrio, JR Phelps, ME Gambhir, SS Herschman, HR TI Monitoring adenoviral DNA delivery, using a mutant herpes simplex virus type 1 thymidine kinase gene as a PET reporter gene SO GENE THERAPY LA English DT Article DE reporter gene; herpes virus thymidine kinase; positron emission tomography ID POSITRON-EMISSION-TOMOGRAPHY; POTENTIAL IMAGING AGENT; LIVING ANIMALS; IN-VIVO; TRANSGENE EXPRESSION; VIRAL-INFECTION; F-18 FHPG; THERAPY; RECEPTOR; PROBE AB Current gene therapy protocols often suffer from an inability to monitor the site, level and persistence of gene expression following somatic DNA delivery. Herpes simplex virus 1 thymidine kinase (HSV1-tk) is currently under intensive investigation as a reporter gene for in vivo imaging of reporter gene expression. The presence of the HSV1-tk reporter gene is repetitively and non-invasively monitored by systemic injection of positron-emitting, radionuclide-labeled thymidine analogues or acycloguanosine HSV1-TK substrates and subsequent detection, by positron emission tomography, of trapped, phosphorylated product. To improve the efficacy of the HSV1-tk PET reporter gene system, both alternative substrates and mutations in the HSV1-tk gene have been described. We used a replication defective adenovirus to deliver the HSV1-sr39tk mutant enzyme and the wild-type HSV1-tk enzyme to mice. HSV1-sr39TK demonstrates greater sensitivity than wild-type HSV1-TK enzyme in vivo, using 9-[(4-[F-18]fluoro-3-hydroxymethylbutyl)guanine as probe, following adenovirus-mediated hepatic expression in mice. Using this adenoviral delivery system, the location, magnitude and duration of HSV1-sr39tk PET reporter gene expression could be non-invasively, quantitatively and repetitively monitored for over 3 months by microPET. C1 Univ Calif Los Angeles, Sch Med, Crump Inst Mol Imaging, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Sch Med, Lab Struct Biol & Mol Med, US DOE, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Sch Med, Dept Mol & Med Pharmacol, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Sch Med, Inst Mol Biol, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Sch Med, Dept Biomath, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Sch Med, Jonsson Comprehens Canc Ctr, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Sch Med, Dept Biol Chem, Los Angeles, CA 90095 USA. RP Herschman, HR (reprint author), Univ Calif Los Angeles, Sch Med, Crump Inst Mol Imaging, 341 Boyer Hall,611 Charles E Young Dr E,341 MBI, Los Angeles, CA 90095 USA. FU NCI NIH HHS [R01 CA82214-01, P50 CA86306, R01 CA84572] NR 35 TC 35 Z9 35 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0969-7128 J9 GENE THER JI Gene Ther. PD DEC PY 2002 VL 9 IS 24 BP 1659 EP 1666 DI 10.1038/sj.gt.3301899 PG 8 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity; Medicine, Research & Experimental SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity; Research & Experimental Medicine GA 626XJ UT WOS:000179898900003 PM 12457279 ER PT J AU Formosa, T Ruone, S Adams, MD Olsen, AE Eriksson, P Yu, YX Rhoades, AR Kaufman, PD Stillman, DJ AF Formosa, T Ruone, S Adams, MD Olsen, AE Eriksson, P Yu, YX Rhoades, AR Kaufman, PD Stillman, DJ TI Defects in SPT16 or POB3 (yFACT) in Saccharomyces cerevisiae cause dependence on the Hir/Hpc pathway: Polymerase passage may degrade chromatin structure SO GENETICS LA English DT Article ID TRANSCRIPTION ELONGATION-FACTOR; CELL-CYCLE PROGRESSION; ASSEMBLY FACTOR-I; ALTER TRANSCRIPTION; SYNTHETIC LETHAL; DNA-REPLICATION; HISTONE GENES; HIR PROTEINS; YEAST; BINDING AB Spt16/Cdc68, Pob3 and Nhp6 collaborate in vitro and in vivo as the yeast factor SPN,which is homologous to human FACT. SPN/FACT complexes mediate passage of polymerases through nucleosomes and are important for both transcription and replication. An spt16 mutation was found to be intolerable when combined with a mutation in any member of the set of functionally related genes HIR1, HIR2/SPT1 HIR3/HPC1, or HPC2. Mutations in POB3, but not in NHP6A/B, also display strong synthetic defects with hir/hpc mutations. A screen for other mutations that cause dependence on HIR/HPC genes revealed genes encoding members of the Paf1 complex, which also promotes transcriptional elongation. The Hir/Hpc proteins affect the expression of histone genes and also promote normal deposition of nucleosomes; either role could explain an interaction with elongation factors. We show that both spt16 and pob3 mutants respond to changes in histone gene numbers, but in opposite ways, suggesting that Spt16 and Pob3 each interact with histones but perhaps with different subsets of these proteins. Supporting this, spt16 and pob3 mutants also display different sensitivities to mutations in the N-terminal tails of histones H3 and H4 and to mutations in enzymes that modulate acetylation of these tails. Our results support a model in which SPN/FACT has two functions: it disrupts nucleosomes to allow polymerases to access DNA, and it reassembles the nucleosomes afterward. Mutations that impair the reassembly activity cause chromatin to accumulate in an abnormally disrupted state, imposing a requirement for a nucleosome reassembly function that we propose is provided by Hir/Hpc proteins. C1 Univ Utah, Sch Med, Dept Biochem, Salt Lake City, UT 84132 USA. Univ Utah, Sch Med, Dept Pathol, Salt Lake City, UT 84132 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. RP Formosa, T (reprint author), Univ Utah, Sch Med, Dept Biochem, 20 N 1900 E,Rm 211, Salt Lake City, UT 84132 USA. OI Stillman, David/0000-0002-5268-2416 FU NIGMS NIH HHS [GM39067, GM64649] NR 58 TC 147 Z9 153 U1 0 U2 3 PU GENETICS PI BALTIMORE PA 428 EAST PRESTON ST, BALTIMORE, MD 21202 USA SN 0016-6731 J9 GENETICS JI Genetics PD DEC PY 2002 VL 162 IS 4 BP 1557 EP 1571 PG 15 WC Genetics & Heredity SC Genetics & Heredity GA 637GB UT WOS:000180502300007 PM 12524332 ER PT J AU Detter, JC Jett, JM Lucas, SM Dalin, E Arellano, AR Wang, M Nelson, JR Chapman, J Lou, YI Rokhsar, D Hawkins, TL Richardson, PM AF Detter, JC Jett, JM Lucas, SM Dalin, E Arellano, AR Wang, M Nelson, JR Chapman, J Lou, YI Rokhsar, D Hawkins, TL Richardson, PM TI Isothermal strand-displacement amplification applications for high-throughput genomics SO GENOMICS LA English DT Article DE rolling circle amplification; RCA; Xylella; whole genome amplification; DNA amplification; DNA isolation ID ROLLING-CIRCLE AMPLIFICATION; PLASMID AB Amplification of source DNA is a nearly universal requirement for molecular biology applications. The primary methods currently available to researchers are limited to in vivo amplification in Escherichia coli hosts and the polymerase chain reaction. Rolling-circle DNA replication is a well-known method for synthesis of phage genomes and recently has been applied as rolling circle amplification (RCA) of specific target sequences as well as circular vectors used in cloning. Here, we demonstrate that RCA using random hexamer primers with Phi29 DNA polymerase can be used for strand-displacement amplification of different vector constructs containing a variety of insert sizes to produce consistently uniform template for end-sequencing reactions. We show this procedure to be especially effective in a high-throughput plasmid production sequencing process. In addition, we demonstrate that whole bacterial genomes can be effectively amplified from cells or small amounts of purified genomic DNA without apparent bias for use in downstream applications, including whole genome shotgun sequencing. C1 US DOE, Joint Genome Inst, Walnut Creek, CA 94598 USA. Amershem Biosci, Piscataway, NJ 08855 USA. RP Richardson, PM (reprint author), US DOE, Joint Genome Inst, 2800 Mitchell Dr, Walnut Creek, CA 94598 USA. NR 14 TC 61 Z9 66 U1 5 U2 19 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD DEC PY 2002 VL 80 IS 6 BP 691 EP 698 DI 10.1006/geno.2002.7020 PG 8 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 628FH UT WOS:000179981600015 PM 12523365 ER PT J AU Rosso, KM Morgan, JJ AF Rosso, KM Morgan, JJ TI Outer-sphere electron transfer kinetics of metal ion oxidation by molecular oxygen SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID EXCHANGE RATE-CONSTANT; AB-INITIO CALCULATION; SELF-EXCHANGE; TRANSFER REACTIVITY; NATURAL-WATERS; MINE DRAINAGE; FREE-ENERGY; FE(II); COMPLEXES; ABINITIO AB Density functional theory molecular orbital calculations and Marcus theory have been combined to assess the rates and physicochemical factors controlling the outer-sphere oxidation of divalent V, Cr, Mn, Fe, and Co aquo and hydroxo ions by O-2 in homogeneous aqueous solution. Key quantities in the elementary oxidation step include the inner-sphere component of the reorganization energy, the thermodynamic driving force, and electrostatic work terms describing the interactions occurring, in this case, between the net charges on the product species. Collectively, these factors and their interplay have a large influence on the rate of the oxidation cross-reaction. An-inner-sphere pathway for the self-exchange reactions and oxidation by O-2 of Mn2+ and Cr2+ ions has been supported indirectly in this study by comparing predicted outer-sphere rates with the results of previous experiments. Likewise, an outer-sphere pathway is suggested for the similar sets of reactions involving the V, Fe, and Co ions. An assessment of the self-exchange reaction for the oxygen/superoxide couple has led to predicted rates in excellent agreement with direct measurements. Predicted rates of oxidation for the hexaquo Fe ion are also in agreement with experiment, while the predicted rates for the outer-sphere oxidation of its hydrolysis products are similar to2 to 3 (monohydroxo) and similar to4 (dihydroxo) orders of magnitude slower than the observed rates. This suggests an inner-sphere pathway is appropriate to explain the relatively fast rates observed for the hydrolyzed Fe species. Copyright (C) 2002 Elsevier Science Ltd. C1 Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. CALTECH, Dept Environm Sci & Engn, Pasadena, CA 91125 USA. RP Rosso, KM (reprint author), Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, POB 999,K8-96, Richland, WA 99352 USA. NR 79 TC 39 Z9 39 U1 3 U2 25 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD DEC PY 2002 VL 66 IS 24 BP 4223 EP 4233 AR PII S0016-7037(02)01040-2 DI 10.1016/S0016-7037(02)01040-2 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 625WA UT WOS:000179837500002 ER PT J AU Perg, LA Anderson, RS Finkel, RC AF Perg, LA Anderson, RS Finkel, RC TI Use of a new Be-10 and Al-26 inventory method to date marine terraces, Santa Cruz, California, USA: Reply SO GEOLOGY LA English DT Article C1 Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Ctr Study Imaging & Dynam Earth, Santa Cruz, CA 95064 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. RP Perg, LA (reprint author), Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD DEC PY 2002 VL 30 IS 12 BP 1148 EP 1148 DI 10.1130/0091-7613(2002)030<1148:>2.0.CO;2 PG 1 WC Geology SC Geology GA 624AZ UT WOS:000179738400025 ER PT J AU Berndt, ML Philippacopoulos, AJ AF Berndt, ML Philippacopoulos, AJ TI Incorporation of fibres in geothermal well cements SO GEOTHERMICS LA English DT Article DE drilling; wells; cement; fibres ID REINFORCED CEMENT AB Fibre-reinforced cements are of potential value in geothermal well cementing jobs due to their ability to withstand higher tensile stresses than conventional cements. Screening tests were performed to evaluate different fibre types with the objective of identifying systems offering the greatest improvement in cement tensile strength. The fibres investigated included steel, stainless steel, carbon, basalt and glass. The baseline cement matrix was standard Class G cement/40% silica flour and variations on this were latex-modification and lightweight formulations incorporating either perlite or microspheres. The fibres that showed the best performance at low volume fraction were 13 mm brass-coated round steel fibres. Steel and carbon microfibres also improved the tensile strength provided the volume fraction was high enough. Thermal and hydraulic properties of cements reinforced with steel fibres were measured and compared with unreinforced mixes. Based on the results, selected fibre types will be used in further property characterization studies and engineering analysis of geothermal wells completed with fibre-reinforced materials. (C) 2002 CNR. Published by Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Energy Sci & Technol, Upton, NY 11973 USA. RP Berndt, ML (reprint author), Brookhaven Natl Lab, Dept Energy Sci & Technol, Upton, NY 11973 USA. EM allan@bnl.gov RI Berndt, Marita/D-1901-2014 OI Berndt, Marita/0000-0002-6622-0597 NR 18 TC 8 Z9 8 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0375-6505 J9 GEOTHERMICS JI Geothermics PD DEC PY 2002 VL 31 IS 6 BP 643 EP 656 AR PII S0375-6505(02)00028-7 DI 10.1016/S0375-6505(02)00028-7 PG 14 WC Energy & Fuels; Geosciences, Multidisciplinary SC Energy & Fuels; Geology GA 618RX UT WOS:000179432000001 ER PT J AU Philippacopoulos, AJ Berndt, ML AF Philippacopoulos, AJ Berndt, ML TI Structural analysis of geothermal well cements SO GEOTHERMICS LA English DT Article DE geothermal wells; cement/sealant; P/T loads; structural models; strength requirements AB Current design procedures are deficient when it comes to the cement/sealant used in geothermal well cementing jobs. The structural performance of the cement is based on the requirement that the cement must have a certain compressive strength. By calculating the response of the cement due to pressure/temperature (P/T) loads, the relevant stress fields are found to be sensitive to a variety of parameters in such a way that they cannot be enveloped solely by the compressive strength of the material. A similar concern also exists in the oil and gas industry. This paper presents a variety of modeling approaches that can be used to perform the necessary structural analysis from which the stress field in the cement can be evaluated. It is recommended that the design of the cement be based on the results from such structural analysis rather than on the basis of the limited requirement for compressive strength. The paper also presents parametric variations of the radial and tangential stresses in the cement that were obtained through coupled analyses of casing-cement-formation models. It is shown that the state of stress in the cement is very sensitive to (a) far-field stress and (b) the relative stiffness between the cement and the formation. (C) 2002 CNR. Published by Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Energy Sci & Technol, Upton, NY 11973 USA. RP Philippacopoulos, AJ (reprint author), Brookhaven Natl Lab, Dept Energy Sci & Technol, Upton, NY 11973 USA. RI Berndt, Marita/D-1901-2014 OI Berndt, Marita/0000-0002-6622-0597 NR 15 TC 5 Z9 5 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0375-6505 J9 GEOTHERMICS JI Geothermics PD DEC PY 2002 VL 31 IS 6 BP 657 EP 676 AR PII S0375-6505(02)00029-9 DI 10.1016/S0375-6505(02)00029-9 PG 20 WC Energy & Fuels; Geosciences, Multidisciplinary SC Energy & Fuels; Geology GA 618RX UT WOS:000179432000002 ER EF