FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Wang, GJ Volkow, ND Fowler, JS Levy, AV Pappas, NR Wong, CT Netusil, N AF Wang, GJ Volkow, ND Fowler, JS Levy, AV Pappas, NR Wong, CT Netusil, N TI Differential regional brain metabolism during fasting in obese and normal body weight subjects. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 410 BP 110P EP 110P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900411 ER PT J AU Ding, YS Studenov, AR Zhang, Z Gerasimov, M Schiffer, W Dewey, SL Telang, F AF Ding, YS Studenov, AR Zhang, Z Gerasimov, M Schiffer, W Dewey, SL Telang, F TI Synthesis and PET studies of [C-11]GVG (Vigabatrin) to better understand its role in drug addiction. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 424 BP 114P EP 114P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900425 ER PT J AU Metzler, SD Bowsher, JE Smith, MF Jaszczak, RJ AF Metzler, SD Bowsher, JE Smith, MF Jaszczak, RJ TI Analytic determination of pinhole collimator sensitivity with penetration. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA USA. Duke Univ, Med Ctr, Durham, NC USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 526 BP 140P EP 140P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900527 ER PT J AU Maltz, JS Budinger, TF AF Maltz, JS Budinger, TF TI Rapid dynamic myocardial SPECT reconstruction from inconsistent projections via iterative least squares method. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 859 BP 200P EP 200P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900758 ER PT J AU Vaska, P Radeka, V Rehak, P Schlyer, DJ Woody, CL AF Vaska, P Radeka, V Rehak, P Schlyer, DJ Woody, CL TI A practical and competitive alternative to mega-crystal PET: A miniature anger detector with LSO and APDS. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 872 BP 203P EP 204P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900771 ER PT J AU Gatley, SJ Gifford, AN Rice, OV Dejesus, OT Shea, CE Shen, J Fowler, JS Volkow, ND AF Gatley, SJ Gifford, AN Rice, OV Dejesus, OT Shea, CE Shen, J Fowler, JS Volkow, ND TI Enantiomerically pure A69024 as a radioligand for dopamine D1 receptors. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Wisconsin, Madison, WI USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 897 BP 210P EP 210P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900796 ER PT J AU Gerasimov, MR Ferrieri, R Schiffer, W Ashby, C Alexoff, D Dewey, S AF Gerasimov, MR Ferrieri, R Schiffer, W Ashby, C Alexoff, D Dewey, S TI Acute toluene exposure antagonizes the effect of cocaine on increases in prefrontal cortex (PFC), but not nucleus accumbens (NACC) dopamine (DA). SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. St Johns Univ, Jamaica, NY 11439 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 901 BP 211P EP 211P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900800 ER PT J AU Gifford, AN Deng, H Gatley, SJ Bruneus, M Dimaio, AA Volkow, ND Makriyannis, A AF Gifford, AN Deng, H Gatley, SJ Bruneus, M Dimaio, AA Volkow, ND Makriyannis, A TI In vivo binding of a novel, potent cannabinoid receptor agonist, AM 2233. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Connecticut, Storrs, CT USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 904 BP 212P EP 212P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900803 ER PT J AU Logan, J Fowler, JS Ding, YS Franceschi, D Wang, GJ Volkow, ND Pappas, N Schlyer, D Kaznatcheev, E Ferrieri, R Shea, C Macgregor, R Garza, V AF Logan, J Fowler, JS Ding, YS Franceschi, D Wang, GJ Volkow, ND Pappas, N Schlyer, D Kaznatcheev, E Ferrieri, R Shea, C Macgregor, R Garza, V TI PET studies of peripheral monoamine oxidase a (MAO A). SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 906 BP 212P EP 212P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900805 ER PT J AU Fowler, JS Logan, J Ding, YS Franceschi, D Wang, GJ Volkow, ND Pappas, N Schlyer, D Gatley, SJ Ferrieri, R Shea, C Garza, V Macgregor, R AF Fowler, JS Logan, J Ding, YS Franceschi, D Wang, GJ Volkow, ND Pappas, N Schlyer, D Gatley, SJ Ferrieri, R Shea, C Garza, V Macgregor, R TI The reduction in the binding of deuterium (D) vs hydrogen (H)-substituted (11)Cclorgyline is not uniform across brain regions. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 908 BP 213P EP 213P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900807 ER PT J AU Schiffer, WK Carter, P Alexoff, DL Fowler, JS Logan, J Shea, C Gerasimov, M Brodie, J Dewey, S AF Schiffer, WK Carter, P Alexoff, DL Fowler, JS Logan, J Shea, C Gerasimov, M Brodie, J Dewey, S TI Manipulations in mechanical ventilation influence the transport constant (K-1) of the reversible radiotracer C-11-cocaine. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NYU, Sch Med, New York, NY USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 909 BP 213P EP 213P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900808 ER PT J AU Franceschi, D Volkow, ND Wang, GJ Fowler, JS Maynard, L Wong, CT Pappas, NR AF Franceschi, D Volkow, ND Wang, GJ Fowler, JS Maynard, L Wong, CT Pappas, NR TI Effect of low dose of alcohol to cerebral glucose metabolism measured with PET. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. SUNY Stony Brook, Upton, NY USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1009 BP 238P EP 238P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900908 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Maynard, L Jayne, M Gatley, SJ Wong, C Pappas, N Franceshi, D Gifford, A Logan, J AF Volkow, ND Wang, GJ Fowler, JS Maynard, L Jayne, M Gatley, SJ Wong, C Pappas, N Franceshi, D Gifford, A Logan, J TI Effects of cocaine detoxification on benzodiazepine-induced changes in regional brain metabolism. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1011 BP 239P EP 239P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900910 ER PT J AU Wang, GJ Volkow, ND Chang, L Fowler, JS Hitzemann, RJ Sedler, M Wong, CT Franceschi, D Pappas, NR AF Wang, GJ Volkow, ND Chang, L Fowler, JS Hitzemann, RJ Sedler, M Wong, CT Franceschi, D Pappas, NR TI Thalamic but not striatal metabolism recovers in methamphetamine abusers with detoxification. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1012 BP 239P EP 239P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900911 ER PT J AU Stabin, MG Siegel, JA Hunt, J Sparks, R Lipsztein, J Eckerman, KF AF Stabin, MG Siegel, JA Hunt, J Sparks, R Lipsztein, J Eckerman, KF TI Radar: The radiation dose assessment resource. An online source of dose information for nuclear medicine and occupational radiation safety. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Vanderbilt Univ, Nashville, TN USA. Nucl Phys Enterprises, Cherry Hill, NJ USA. Comis Nacl Energia Atom, Rio De Janeiro, Brazil. Creat Dev Enterprises, Knoxville, TN USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 0 TC 8 Z9 9 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1027 BP 243P EP 243P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900926 ER PT J AU Stabin, MG Eckerman, KF Bolch, WE Bouchet, LG AF Stabin, MG Eckerman, KF Bolch, WE Bouchet, LG TI Consensus bone and marrow model for internal dose assessment. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Vanderbilt Univ, Knoxville, TN USA. Oak Ridge Natl Lab, Knoxville, TN USA. Univ Florida, Gainesville, FL USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1029 BP 244P EP 244P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900928 ER PT J AU Gerasimov, MR Ferrieri, R Schiffer, W Ashby, C Garza, V Shea, C Studenov, A Macgregor, R AF Gerasimov, MR Ferrieri, R Schiffer, W Ashby, C Garza, V Shea, C Studenov, A Macgregor, R TI (11)CToluene, a new radiotracer for imaging brain pharmacokinetics and biodistribution of a commonly abused solvent. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. St Johns Univ, Jamaica, NY 11439 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1062 BP 252P EP 252P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900961 ER PT J AU Freimuth, P Meinken, G Springer, K Srivastava, S AF Freimuth, P Meinken, G Springer, K Srivastava, S TI Imaging potential of the recombinant knob domain of adenovirus fiber protein. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1066 BP 253P EP 254P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900965 ER PT J AU Kolsky, KL Mausner, LF Awasthi, V Srivastava, SC Zhuikov, BL Lapshina, EV Kokhanyuk, V Kravchuk, VL Vincent, J Zyuzin, A Phillips, D Jamriska, D AF Kolsky, KL Mausner, LF Awasthi, V Srivastava, SC Zhuikov, BL Lapshina, EV Kokhanyuk, V Kravchuk, VL Vincent, J Zyuzin, A Phillips, D Jamriska, D TI Production of (PD)-P-103 from silver targets with high energy protons at blip. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Nucl Res Inst, Moscow, Russia. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1086 BP 258P EP 258P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900983 ER PT J AU Meinken, GE Li, Z James, JL Srivastava, S AF Meinken, GE Li, Z James, JL Srivastava, S TI Improved formulation of Sn-117m DTPA suitable for high-dose therapeutic administration. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Diatide Res Labs, Londonderry, NH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1085 BP 258P EP 258P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821900982 ER PT J AU Alexoff, D Shea, C Ferrieri, R Gerasimov, M Garza, V Macgregor, R King, P AF Alexoff, D Shea, C Ferrieri, R Gerasimov, M Garza, V Macgregor, R King, P TI Characterization of plasma radioactivity by robotic SPE and HPLC following intravenous administration of C-11-toluene in baboon. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 2001 VL 42 IS 5 SU S MA 1120 BP 267P EP 267P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 434NG UT WOS:000168821901017 ER PT J AU Johnson, VM Rogers, LL AF Johnson, VM Rogers, LL TI Applying soft computing methods to improve the computational tractability of a subsurface simulation-optimization problem SO JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING LA English DT Article DE neural networks; genetic algorithms; optimization; simulation; petroleum engineering ID GROUNDWATER REMEDIATION; GENETIC ALGORITHMS; NEURAL NETWORKS; MANAGEMENT; FIELD; PERFORMANCE; DESIGN; SOLVE AB Formal optimization strategies normally evaluate hundreds or even thousands of scenarios in the course of searching for the optimal solution to a given management question. This process is extremely time-consuming when numeric simulators of the subsurface are used to predict the efficacy of a scenario. One solution is to train artificial neural networks (ANNs) to stand in for the simulator during the course of searches directed by some optimization technique such as the genetic algorithm (GA) or simulated annealing (SA). The networks are trained from a representative sample of simulations, which forms a re-useable knowledge base of information for addressing many different management questions. These concepts were applied to a water flood project at BP's Pompano Field. The management problem was to locate the combination of 1-4 injection locations that would maximize Pompano's simple net profit over the next 7 years. Using a standard industry reservoir simulator, a knowledge base of 550 simulations sampling different combinations of 25 potential injection locations was created. The knowledge base was first queried to answer questions concerning optimal scenarios for maximizing simple net profit over 3 and 7 years. The answers indicated that a considerable increase in profits might be achieved by expanding from an approach to injection depending solely on converting existing producers to one involving the drilling of three to four new injectors, despite the increased capital expenses. Improved answers were obtained when the knowledge base was used as a source of examples for training and testing ANNs. ANNs were trained to predict peak injection volumes and volumes of produced oil and gas at 3 and 7 years after the commencement of injection. The rapid estimates of these quantities provided by the ANNs were fed into net profit calculations, which in turn were used by a GA to evaluate the effectiveness of different well-field scenarios. The expanded space of solutions explored by the OA contained new scenarios that exceeded the net profits of the best scenarios found by simply querying the knowledge base. To evaluate the impact of prediction errors on the quality of solutions. the best scenarios obtained in searches where ANNs predicted oil and pas production were compared with the best scenarios found when the reservoir simulator itself generated those predictions during the course of search. Despite the several thousand CPU hours required to complete the simulator-based searches, the resulting best scenarios failed to match the best scenarios uncovered by the ANN-based searches. Lastly, results obtained from ANN-based searches directed by the GA were compared with ANN-based searches employing an SA algorithm. The best scenarios generated by both search techniques were virtually identical. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Johnson, VM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 34 TC 22 Z9 22 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-4105 J9 J PETROL SCI ENG JI J. Pet. Sci. Eng. PD MAY PY 2001 VL 29 IS 3-4 BP 153 EP 175 DI 10.1016/S0920-4105(01)00087-0 PG 23 WC Energy & Fuels; Engineering, Petroleum SC Energy & Fuels; Engineering GA 442LJ UT WOS:000169287000002 ER PT J AU Chen, MJ Klingler, RJ Rathke, JW AF Chen, MJ Klingler, RJ Rathke, JW TI Rh(III) complexes of singly and doubly reduced phthalocyanine ligands generated by chemical and electrochemical reduction SO JOURNAL OF PORPHYRINS AND PHTHALOCYANINES LA English DT Article DE rhodium; phthalocyanine; ring reduction; ring contraction; protonation of meso nitrogens; paramagnetic; antiaromatic ID RHODIUM AB The paramagnetic complexes (FPc)(Me)Rh- (4) and (FPc)(PMe3)(Me)Rh- (10) have been prepared by reducing (FPc)(Me)Rh (1) and (FPc)(PMe3)(Me)Rh (2) with NaBH4 in methanol-d(4) [FPc2- = dianion of 1,4,8,11,15,18,22,25-octakis(trifluoromethyl)phthalocyanine]. Compounds 4 and 10 are further reduced by NaBH4 to complexes, which are assigned to (DFPc)(Me)Rh- (5) and (DFPc)(PMe3)(Me)Rh- (11), respectively. Based on the H-1 NMR spectra or these complexes, 4 and 10 are assigned to the Rh(III) complexes of the singly reduced radical anion FPc.3-, while 5 and 11 are assigned to the Rh(III) complexes of the doubly reduced, antiaromatic anion DFPc3-, which has the deuteron bonded to one of its meso nitrogens. As expected, the antiaromatic complexes 5 and 11 are not stable. At 40 degreesC, 5 was transformed successively into three aromatic compounds, the first of which was assigned to the ring-contracted alpha,beta,gamma -triazatetrabenzocorrole complex (TBC)(Me)Rh- [TBC3- = trianion of 3,6,10,13,17,20,24,27-octakis(trifluoromethyl)-alpha,beta,gamma -triazatetrabenzocorrole]. Cyclic voltammetry of 1 and 2 was also carried out. Two reversible one-electron reduction waves were observed for both 1 and 2. Published in 2001 by John Wiley & Sons, Ltd. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Chen, MJ (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 3 Z9 3 U1 1 U2 2 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1088-4246 J9 J PORPHYR PHTHALOCYA JI J. Porphyr. Phthalocyanines PD MAY PY 2001 VL 5 IS 5 BP 442 EP 448 DI 10.1002/jpp.335 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 428BY UT WOS:000168442300003 ER PT J AU Howe, SD Travis, B Zerkle, DK AF Howe, SD Travis, B Zerkle, DK TI Safe testing of nuclear rockets SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB In the early 1960s, Werner Von Braun and others recognized the need for a nuclear rocket for sending humans to Mars. The great distances, the intense radiation levels, and the physiological response to zero gravity all support the concept of using a nuclear rocket to decrease mission time. These same needs have been recognized in later studies and, especially, in the Space Exploration Initiative in 1989. One of the key questions that has arisen in later studies, however, is the ability to test a nuclear rocket engine in the current societal environment. Unlike the Rover/Nuclear Engine for Rocket Vehicle Applications programs in the 1960s, the rocket exhaust can no longer be vented to the open atmosphere. As a consequence, previous studies have examined the feasibility of building a large-scale version of the Nuclear Furnace Scrubber that was demonstrated in 1971. We have investigated an alternative that would deposit the rocket exhaust along with any entrained fission products directly into the ground. The subsurface active filtering of exhaust concept would allow variable-sized engines to be tested for long times at a modest expense. A system overview, results of preliminary calculations, and current status of a proof-of-concept demonstration are presented. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Howe, SD (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS-B259, Los Alamos, NM 87545 USA. NR 8 TC 3 Z9 3 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2001 VL 17 IS 3 BP 534 EP 539 DI 10.2514/2.5808 PG 6 WC Engineering, Aerospace SC Engineering GA 434FN UT WOS:000168804600007 ER PT J AU Lowrie, RB Mihalas, D Morel, JE AF Lowrie, RB Mihalas, D Morel, JE TI Comoving-frame radiation transport for nonrelativistic fluid velocities SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE radiation hydrodynamics; radiation transport ID SPECIAL RELATIVISTIC EQUATION; HYDRODYNAMICS; FLOWS AB We investigate the comoving-frame treatment of radiation transport for use in problems of nonrelativistic radiation hydrodynamics. The transport equation is re-derived, to O(v/c), retaining a term that is traditionally omitted. This reduced equation is not just formally, but also physically, correct to O(v/c), inasmuch as it keeps the wave speed bounded by light speed and can transformed to the correct Eulerian-frame transport equation in any physical regime. We strongly recommend that this equation, and its moments, be used in all situations where the fluid-flow speeds are nonrelativistic. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Appl Phys, Hydrodynam Methods Grp X 3, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Appl Phys, Transport Methods Grp X 6, Los Alamos, NM 87545 USA. RP Lowrie, RB (reprint author), Univ Calif Los Alamos Natl Lab, Div Appl Phys, Hydrodynam Methods Grp X 3, Mail Stop D413, Los Alamos, NM 87545 USA. NR 12 TC 16 Z9 16 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD MAY 1 PY 2001 VL 69 IS 3 BP 291 EP 304 DI 10.1016/S0022-4073(00)00085-6 PG 14 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 414ZU UT WOS:000167696700003 ER PT J AU Lepel, EA Hensley, WK Brodzinski, RL Smart, JE AF Lepel, EA Hensley, WK Brodzinski, RL Smart, JE TI Calibration of an automated high resolution gamma-ray spectroscopy system for in-situ real-time monitoring of a processed waste effluent stream SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB A pilot plant is being designed at the U. S. Department of Energy's Savannah River Site (SRS) to demonstrate the removal of Sr-90, Cs-137, and transuranics from a high-level liquid waste stream prior to encapsulation in a Saltstone Facility. In-line monitors are required to determine the concentration of all radionuclides on this processed waste stream. Calibration standards containing Co-60, Cs-137, and Sr-90 were prepared and counted. Efficiency curves were generated. Strontium-90 is readily observable above the system background in the calibration standard count, and is observable at less than 3 nCi/ml in a mixed solution having the maximum allowable concentration of all other activities present in the proposed SRS effluent stream. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Lepel, EA (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd, Richland, WA 99352 USA. NR 2 TC 0 Z9 0 U1 1 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 273 EP 277 DI 10.1023/A:1010690900538 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000004 ER PT J AU Brodzinski, RL Craig, RA Hensley, WK Lepel, EA Seymour, R Smart, JE AF Brodzinski, RL Craig, RA Hensley, WK Lepel, EA Seymour, R Smart, JE TI A neutron monitor for in-situ real-time determination of transuranics in a processed waste effluent stream SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB A pilot plant operation at the Savannah River Site will remove Sr-90, Cs-137, and transuranics from a high-level liquid waste stream prior to encapsulation in a Saltstone Facility. Monitors are required to determine the concentrations of all radionuclides, including transuranics, in real-time on this processed waste stream. A neutron counter used to measure the concentration of each actinide isotope present in the stream is described. The neutron counter assembly consists of nested annular layers of shielding, reflectors, detectors, and moderators. On-line, live-time system control and calibration is provided by a time-tagged neutron source embedded in the moderator assembly. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. NucSafe LLC, Clinton, TN 37716 USA. RP Brodzinski, RL (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 279 EP 281 DI 10.1023/A:1010643017376 PG 3 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000005 ER PT J AU Prettyman, TH Ianakiev, KD Moss, CE Soldner, SA Sweet, MR Browne, MC AF Prettyman, TH Ianakiev, KD Moss, CE Soldner, SA Sweet, MR Browne, MC TI Development of high efficiency, multi-element CdZnTe detectors for portable measurement applications SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top ID PERFORMANCE; READOUT; ARRAYS; RAY AB We describe the development of detector arrays and electronics for large-volume, hand-held CdZnTe detectors with the same counting efficiency as portable NaI(Tl) detectors presently used for nuclear material measurement applications. The pulse-height resolution of the multi-element detectors is at least three times better than NaI(Tl) over a wide energy range from 100 keV to several MeV), enabling more accurate measurements of gamma-rays emitted by special nuclear material. Arrays of up to eight coplanar grid detectors can be combined to make detectors ranging in size from 4 to 14 cm(3). Because the number of spectroscopy channels is small, low-power, hand-held detectors can be manufactured with conventional printed circuit board technology, thus keeping the cost of multi-element detectors to a minimum. The design and performance of an 8-element detector is presented. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EV Prod, Saxonburg, PA 16065 USA. RP Prettyman, TH (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. OI Prettyman, Thomas/0000-0003-0072-2831 NR 13 TC 12 Z9 15 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 295 EP 300 DI 10.1023/A:1010699102355 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000008 ER PT J AU Beals, DM Hofstetter, KJ Johnson, VG Patton, GW Seely, DC AF Beals, DM Hofstetter, KJ Johnson, VG Patton, GW Seely, DC TI Development of field portable sampling and analysis systems SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB A portable, field rugged, sampling and analysis system has been developed for the rapid screening of aqueous samples during scoping and remediation studies. Using field portable equipment, water is pumped through ion selective solid phase extraction (SPE) disks, at a now rate of 150-250 ml/min, and counted for the radionuclide of interest in the field using portable detectors. SPE disks are currently available to selectively concentrate Tc-99, Sr-90, radiocesium (Cs-134 and (CS)-C-137) and radium isotopes. In the field the radiocesium concentration is determined by gammaspectrometry, Sr-90 and Tc-99 are determined by beta-counting. A one-liter sample can be processed and ready for counting within ten minutes. Using a 5-minute counting time, a detection limit of < 50 pCi/l for Tc-99 or Sr-90 and similar to 50 pCi/l for Cs-137 has been achieved. Up to 10 liters of water have been processed for the analysis of Tc-99 and Cs-137 when lower limits of detection were required. The sampling and analysis system has been field tested at the Savannah River Site (SRS), Aiken SC, and the Hanford Site, Richland WA. The SRS H-area tank farm storm water runoff system was analyzed for Sr-90 and Cs-137. Groundwater from the SX tank farm at the Hanford Site was analyzed for Cs-137 and Tc-99. Groundwater from seeps below the 100-H area at Hanford was analyzed for Sr-90 and Tc-99. C1 Savannah River Technol Ctr, WSRC, Aiken, SC 29808 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. 3M Co, Filtrat Prod, St Paul, MN 55144 USA. RP Beals, DM (reprint author), Savannah River Technol Ctr, WSRC, Aiken, SC 29808 USA. NR 9 TC 6 Z9 6 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 315 EP 319 DI 10.1023/A:1010655420102 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000011 ER PT J AU Revay, Z Molnar, GL Belgya, T Kasztovszky, Z Firestone, RB AF Revay, Z Molnar, GL Belgya, T Kasztovszky, Z Firestone, RB TI A new gamma-ray spectrum catalog and library for PGAA SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB New measurements have been performed at the PGAA facility at the Budapest Research Reactor (BRR) in order to create a prompt gamma -ray catalog for qualitative and quantitative analysis. The measured spectra were accurately analyzed by HYPERMET-PC. Prompt gamma -ray energies and associated gamma -ray production cross-sections have been determined by internal standardization. The resulting catalog contains prompt gamma -ray data from neutron capture and other reactions such as (n,alpha), and decay gamma -ray data from short-lived reaction products. Data have been measured for nearly all stable elements, from hydrogen to uranium. Generally, data for several isotopes are given, to enable isotopic analysis as well. The whole library, including elemental spectra, will be available as a book. C1 Inst Isotope & Surface Chem, Chem Res Ctr, H-1525 Budapest, Hungary. Univ Calif Berkeley, Lawrence Berkeley Lab, Isotopes Project, Berkeley, CA 94720 USA. RP Revay, Z (reprint author), Inst Isotope & Surface Chem, Chem Res Ctr, POB 77, H-1525 Budapest, Hungary. OI Firestone, Richard/0000-0003-3833-5546 NR 7 TC 17 Z9 19 U1 1 U2 10 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 395 EP 399 DI 10.1023/A:1010684210532 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000023 ER PT J AU Zeissler, CJ Lindstrom, RM McKinley, JP AF Zeissler, CJ Lindstrom, RM McKinley, JP TI Radioactive particle analysis by digital autoradiography SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top ID IMAGING PLATE; PHOSPHORS AB We have been exploring ways to evaluate the activity of radioactive particles that have been detected by phosphor plate digital autoradiography based on photostimulated luminescence (PSL). A PSL system with 25 mum pixel digitization has been applied to particle analysis problems, both qualitatively and quantitatively. Two data evaluation methods are currently employed: (1) bulk area signal measurement, and (2) discrete event counting which may include spectral evaluation. The first method is conventional, whereas the second method requires high spatial resolution and is presented here for the first time. The counting methods can discriminate between alpha and background counts. The unshielded background signal accumulation rate was determined by the bulk area method. Using the spectral method of evaluation for a-particle events, the mean signal intensity per recorded a-particle was measured, and the detective quantum efficiency (DQE) was found to be nominally 100%. We present a comparison to gamma-spectrometry for sub-Bq Cs-137 activities, and demonstrate an application for the qualitative assay of International Atomic Energy Agency swipe samples collected from uranium enrichment facilities. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Zeissler, CJ (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 19 TC 20 Z9 20 U1 0 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 407 EP 412 DI 10.1023/A:1010640411441 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000025 ER PT J AU Ghanbari, F Mohagheghi, AH AF Ghanbari, F Mohagheghi, AH TI Use of gamma-ray spectroscopy for direct detection of thermal neutrons SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB A neutron detector based on detection of the prompt gamma-radiation emitted as a result of neutron interaction with a suitable neutron absorber is described. Boron-10 loaded polyethylene is used as the neutron converter. Neutrons are thermalized in the polyethylene and are subsequently absorbed by B-10. The result of the neutron absorption is production of Li-7, in the excited state (Li-7*) and an alpha-particle. This occurs for 94% of the absorbed neutrons. The Li-7* (T-1/2 = 10(-13) S) emits a 477.6 keV gamma-ray ("prompt" gamma-ray) after it is formed and may be detected in a gamma-ray spectroscopy system. Since the "prompt" gamma-ray peak is Doppler broadened - the recoiled Li-7* emits the gamma-ray on "fly" - it is easily distinguishable from other non-capture gamma-ray peaks. The neutron converter, B-10 loaded into a polyethylene end cap placed on the standard gamma-ray spectroscopy detector, adds the neutron detection capability without impeding the system's gamma-ray spectroscopy characteristics. Results for detection of neutrons from a moderated Cf-252 source are presented. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ghanbari, F (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 3 Z9 3 U1 1 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 413 EP 416 DI 10.1023/A:1010692428279 PG 4 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000026 ER PT J AU Gehrke, RJ Davidson, JR Taylor, PJ Helmer, RG Mandler, JW AF Gehrke, RJ Davidson, JR Taylor, PJ Helmer, RG Mandler, JW TI Radioactinide additions to the electronic gamma-ray spectrum catalogue SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB With the completion of a CD ROM version of the original R. L. HEATH's Gamma-ray Spectrum Catalogue, it became obvious that a number of radionuclides are missing which are important to various fields of nuclear science and technology. With a large amount of transuranic waste awaiting permanent disposal across the Department of Energy (DOE) complex and the need for its assay in order to dispose of it, it was decided that the addition of the radioactinides encountered in transuranic waste should be the first priority. In response to this need, the spectra of U-233, U-235, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241 and Am-243 have been acquired with modem Ge detectors, and prepared for graphics presentation along with the parent and progeny decay chains and decay schemes. The associated tables of gamma -ray energies and emission probabilities have been downloaded from the Evaluated Nuclear Structure Data file ENSDF) database. This information is being incorporated into the Gamma-Ray Spectrometry Center Web Site at http.//id.inel.gov/gamma. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Gehrke, RJ (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 417 EP 422 DI 10.1023/A:1010644529188 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000027 ER PT J AU Wagner, SE Boone, S Chamberlin, JW Duffy, CJ Efurd, DW Israel, KM Koski, NL Kottmann, DL Lewis, D Lindahl, PC Roensch, FR Steiner, RE AF Wagner, SE Boone, S Chamberlin, JW Duffy, CJ Efurd, DW Israel, KM Koski, NL Kottmann, DL Lewis, D Lindahl, PC Roensch, FR Steiner, RE TI Practical application of thermal ionization mass spectrometry for the determination of plutonium for the LANL Bioassay Program (LA-UR-00-1697) SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB Utilization of thermal ionization mass spectrometry as a routine analytical service provided to the Los Alamos National Laboratory Bioassay Program has evolved significantly since its implementation just over three years ago. Converting this unique research tool designed to support nuclear weapons testing to a quasi-production mode for the routine analysis of similar to 300 urine samples/year for ultra-low levels of plutonium has required resolution of numerous practical issues. These issues include clean-room sample preparation, adequate tracer recovery, customer specified turn-around times, throughput, water and urine blank values, statistical data reduction, and quality control and performance evaluation sample requirements. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Wagner, SE (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS J514, Los Alamos, NM 87545 USA. NR 4 TC 8 Z9 8 U1 2 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 423 EP 429 DI 10.1023/A:1010648613258 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000028 ER PT J AU Moody, EW Barr, ME Jarvinen, GD AF Moody, EW Barr, ME Jarvinen, GD TI QSAR of distribution coefficients for Pu(NO3)(6)(2-) complexes using molecular mechanics SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB Computer-aided modeling has been very successful in the design of chelating ligands for the formation of selective metal complexes. We report herein preliminary efforts to extend the principles developed for ion-specific chelating ligands to the weaker, more diffuse electrostatic interactions between complex anions and dicationic sites of anion-exchange resins. We present formal- and partial-charge methodologies for determining calculated electrostatic affinity between plutonium(IV) hexanitrato dianions and free analogues of dicationic anion-exchange sites. Both approaches correlate well with empirically-determined distribution coefficients for our bifunctional pyridinium-based resins (0.65 < r(2) < 0.98). This quantitative structure activity relationship (QSAR) will be useful in the determination of which structural modifications within a select series of bifunctional resins are most likely to be advantageous. Ultimately, we hope to refine this methodology to allow the a priori determination of ion-exchange behavior for a broad class of materials. C1 Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Moody, EW (reprint author), Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, POB 1663, Los Alamos, NM 87545 USA. NR 11 TC 1 Z9 1 U1 2 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 431 EP 437 DI 10.1023/A:1010600730097 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000029 ER PT J AU Barr, ME Schulte, LD Jarvinen, GD Espinoza, J Ricketts, TE Valdez, Y Abney, KD Bartsch, RA AF Barr, ME Schulte, LD Jarvinen, GD Espinoza, J Ricketts, TE Valdez, Y Abney, KD Bartsch, RA TI Americium separations from nitric acid process effluent streams SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top ID NUCLEAR WASTE TREATMENT; ANION-EXCHANGE RESINS AB Plutonium recovery operations offer several points at which americium removal may be attempted, and we are evaluating two classes of materials targeted at different steps in the process. Extraction chromatography resin materials loaded with three different alkylcarbamoyl phosphinates and phosphine oxides are assessed for Am removal efficiency and Am/Fe selectivity from 1-7M nitric acid solutions. Commercial and experimental anion exchange resins are evaluated for total alpha-activity removal from post-evaporator solutions whose composition, relative to the original nitric acid effluent, is reduced in acid and greatly increased in total salt content. With both classes of materials, americium and/or total-alpha reduction is sufficient to meet regulatory requirements even under sub-optimal conditions. Batch distribution coefficients and column performance data are presented. C1 Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Texas Tech Univ, Dept Chem & Biochem, Lubbock, TX 79409 USA. RP Barr, ME (reprint author), Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, POB 1663, Los Alamos, NM 87545 USA. NR 14 TC 11 Z9 11 U1 1 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 457 EP 465 DI 10.1023/A:1010613100054 PG 9 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000034 ER PT J AU Borkowski, M Moore, RC Bronikowski, MG Chen, JF Pokrovsky, OS Xia, YX Choppin, GR AF Borkowski, M Moore, RC Bronikowski, MG Chen, JF Pokrovsky, OS Xia, YX Choppin, GR TI Thermodynamic modeling of actinide complexation with oxalate at high ionic strength SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top ID MEDIA; NP(V) AB A geochemical model describing the solubility of actinides in underground water at the Waste Isolation Pilot Plant (WIPP) Project is under development. The database for this model consists of standard chemical potentials and Fitter model parameters for hundreds of species that may be present in the WIPP disposal room. Organic ligands used in separation and decontamination processes may be present in the nuclear wastes placed in the WIPP site and could have a significant impact on mobile actinide concentrations. In this work the beta (1) and beta (2) stability constants of NpO2+, UO22+ Am-3(+) and Th-4(+) with the oxalate anion have been measured in 0.3-5.0M NaCl media at 25 degreesC by a solvent extraction technique. For the 1:1 complexation, the values of the stability constants increased in the order: NpO2+< Am3+< UO22+< Th4+, in accordance with the actinide charge density and reflecting the strongly ionic bonding of the complexes. The Fitter ionic interaction model was used to model the data Because the data were collected mainly in the high ionic strength region, values of beta ((1)) were estimated from these plus literature values. The Fitter model gives a good representation of the data using three interaction parameters beta ((0)), beta ((1)), and c(phi). C1 Florida State Univ, Dept Chem, Tallahassee, FL 32306 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Borkowski, M (reprint author), Florida State Univ, Dept Chem, Tallahassee, FL 32306 USA. OI Pokrovsky, Oleg/0000-0002-3155-7069 NR 24 TC 22 Z9 22 U1 1 U2 12 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2001 VL 248 IS 2 BP 467 EP 471 DI 10.1023/A:1010665116893 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 446MA UT WOS:000169516000035 ER PT J AU Fayek, M Harrison, TM Grove, M McKeegan, KD Coath, CD Boles, JR AF Fayek, M Harrison, TM Grove, M McKeegan, KD Coath, CD Boles, JR TI In situ stable isotopic evidence for protracted and complex carbonate cementation in a petroleum reservoir, North Coles Levee, San Joaquin Basin, California, USA SO JOURNAL OF SEDIMENTARY RESEARCH LA English DT Article ID COMPACTION PROCESSES; RELATIVE IMPORTANCE; FORMATION WATERS; ACID ANIONS; ELK HILLS; OXYGEN; SANDSTONE; DOLOMITIZATION; POROSITY; HISTORY AB Knowledge of the evolution of carbonate cementation in hydrocarbon reservoirs is key to understanding the history of fluid flow during petroleum accumulation. The Stevens sands is a sequence of marine shales and deep-sea fan sands that was deposited within the Miocene Monterey Formation in the south-central part of the San Joaquin basin, California, during the upper Miocene (10-6 hla). Rapid, high-precision in situ oxygen and carbon isotopic analyses of carbonate phases using the ion microprobe operated in multi-collection mode, in conjunction dth electron microprobe analyses, indicate that carbonate cement zones within the Stevens sands at North Coles Levee (NCL) have had a complex and protracted fluid history. Three main generations of carbonate cement were identified. The relative timing of carbonate cement precipitation within the Stevens sands at NCL was estimated using the thermal and burial history of the San Joaquin basin, in situ oxygen isotope data, and cementation temperatures derived from equilibrium oxygen isotope fractionation factors for calcite-water and dolomite-water. Precipitation of these cement zones began soon after sediment deposition (similar to 7 Ma) and is ongoing. Early dolomite was precipitated at a temperature of similar to 10 degreesC, near the sediment-water interface, and soon after sediment deposition: Calcite cements, which are the most abundant variety, precipitated semicontinuously between 4 Ma and 5 Ma, at temperatures between 50 degreesC and 65 degreesC, and depths of 800 m to 1300 m. Fe-dolomite, which is paragenetically late, appears to have precipitated at temperatures near 100 degreesC in response to pore-pressure reduction, which accompanied exploitation of the gas cap within the last 35 years. Carbon in these cements was likely derived from several sources including marine, maturing hydrocarbons, and a zone of methanogenesis. C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. Univ Calif Santa Barbara, Dept Geol Sci, Santa Barbara, CA 93106 USA. RP Univ Tennessee, Oak Ridge Natl Lab, Dept Geol Sci, Knoxville, TN 37996 USA. EM mfayed@utk.edu RI McKeegan, Kevin/A-4107-2008; Harrison, Timothy/E-7443-2012; UCLA, SIMS/A-1459-2011; OI McKeegan, Kevin/0000-0002-1827-729X; Coath, Christopher/0000-0002-6520-2223 NR 65 TC 18 Z9 23 U1 1 U2 6 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 6128 EAST 38TH ST, STE 308, TULSA, OK 74135-5814 USA SN 1527-1404 EI 1938-3681 J9 J SEDIMENT RES JI J. Sediment. Res. PD MAY PY 2001 VL 71 IS 3 BP 444 EP 458 DI 10.1306/2DC40954-0E47-11D7-8643000102C1865D PN A PG 15 WC Geology SC Geology GA 428JN UT WOS:000168458700013 ER PT J AU Das, B Pitzer, KS AF Das, B Pitzer, KS TI Thermodynamic properties of aqueous potassium fluoride under superambient conditions SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Article DE pressure dependence of thermodynamic properties; activity coefficients; osmotic coefficients; apparent molar volume; ion association; electrolytes; potassium fluoride ID ALKALI-METAL SULFATES; 30 MPA; NA2SO4(AQ) AB Using the ion-interaction or virial coefficient approach developed by Fitter, the pressure dependences of the osmotic and activity coefficients for KF (aq.) up to 473.15 K and 2.5.0 mol-kg(-1) have been calculated from literature data for the apparent molar volumes of KF (aq.). These pressure dependencies were combined with the osmotic and activity coefficient at 0.1 MPa or p(sat), obtained from the model of Saluja et al. to yield a comprehensive set of thermodynamic properties for KF (aq.) at temperatures from 298.15 through 473.15 K, pressures 10, 20, and 30 MPa, and molalities to 2.5 mol-kg(-1). C1 Univ N Bengal, Dept Chem, Raja Rammohanpur 734430, W Bengal, India. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Das, B (reprint author), Univ N Bengal, Dept Chem, Raja Rammohanpur 734430, W Bengal, India. NR 14 TC 3 Z9 3 U1 0 U2 4 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD MAY PY 2001 VL 30 IS 5 BP 489 EP 496 DI 10.1023/A:1010356716735 PG 8 WC Chemistry, Physical SC Chemistry GA 449WU UT WOS:000169710800008 ER PT J AU Yu, QW Takeda, T Yuasa, T Hasegawa, Y Wu, J Thet-Thet-Lwin Hyodo, K Dilmanian, FA Itai, Y Akatsuka, T AF Yu, QW Takeda, T Yuasa, T Hasegawa, Y Wu, J Thet-Thet-Lwin Hyodo, K Dilmanian, FA Itai, Y Akatsuka, T TI Preliminary experiment of fluorescent X-ray computed tomography to detect dual agents for biological study SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE fluorescent X-rays; computed tomography; iodine; xenon; multi-agents simultaneous detection ID SYNCHROTRON-RADIATION; RECONSTRUCTION; SYSTEM; CT AB The simultaneous observation of various information, such as blood flow, tissue metabolism and distribution of receptors, is quite important in order to understand the functional state of biomedical objects. The simultaneous detectability of contrast agents by fluorescent X-ray computed tomography (FXCT) with synchrotron radiation is examined in this study. The system consisted of a silicon (111) double-crystal monochromator, an X-ray slit system, a scanning table, a PIN diode, a highly purified germanium detector and an X-ray charge-coupled device (CCD) camera. The monochromatic X-ray beam energy was adjusted to 37.0 keV and collimated into a pencil beam of 1 x 1 mm. The fluorescent spectra of the K alpha lines for iodine and xenon were detected simultaneously. FXCT could image the distribution of both iodine and xenon agents in a phantom clearly and the contrast ratio was significantly better than that of transmission X-ray computed tomography images. C1 Univ Tsukuba, Inst Clin Med, Tsukuba, Ibaraki 3058575, Japan. Yamagata Univ, Fac Engn, Yamagata 9928510, Japan. High Energy Accelerator Res Org, Mat Struct Sci, Tsukuba, Ibaraki 305, Japan. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Takeda, T (reprint author), Univ Tsukuba, Inst Clin Med, Tsukuba, Ibaraki 3058575, Japan. RI Yuasa, Tetsuya/F-5006-2013 NR 23 TC 18 Z9 18 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY PY 2001 VL 8 BP 1030 EP 1034 DI 10.1107/S0909049500020483 PN 3 PG 5 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 425HC UT WOS:000168284300004 PM 11486409 ER PT J AU Bellacchio, E McFarlane, KL Rompel, A Robblee, JH Cinco, RM Yachandra, VK AF Bellacchio, E McFarlane, KL Rompel, A Robblee, JH Cinco, RM Yachandra, VK TI Counting the number of disulfides and thiol groups in proteins and a novel approach for determining the local pK(a) for cysteine groups in proteins in vivo SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE sulfur K-edge; XANES; thiol; disulfide ID RAY-ABSORPTION SPECTROSCOPY; REDOX STATE; SULFUR AB X-ray Absorption Spectroscopy (XAS) is a powerful tool to investigate sulfur in biological molecules. The spectral features are sensitive to the local electronic and geometric environment of the atom; thus, they constitute a fingerprint of the different chemical forms in which the sulfur is present. This allows straightforward detection of the ratio between free thiols and disulfides. Intra- or inter-molecular disulfide bond formation between residues plays an important role in structural and conformational changes in proteins, and such changes can be investigated using sulfur XAS. Also, a thiolate-disulfide equilibrium is involved in the regulation of the redox potential in the cells by means of modulating the concentrations of the reduced (thiolate) and oxidized (disulfide) form of the tripeptide glutathione. Thus, we can monitor the redox state of a cell by means of sulfur XAS. Thiols also exhibit an acid-base equilibrium, and sulfur XAS can be used to determine the local pK(a) of the -SH group. Here we report examples of how sulfur XAS has been used for these applications. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys Biosci, Melvin Calvin Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Yachandra, VK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys Biosci, Melvin Calvin Lab, Berkeley, CA 94720 USA. NR 5 TC 9 Z9 9 U1 0 U2 5 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY PY 2001 VL 8 BP 1056 EP 1058 DI 10.1107/S0909049500017210 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 425HC UT WOS:000168284300010 PM 11486415 ER PT J AU Wang, SQ Setlow, R Berwick, M Polsky, D Marghoob, AA Kopf, AW Bart, RS AF Wang, SQ Setlow, R Berwick, M Polsky, D Marghoob, AA Kopf, AW Bart, RS TI Ultraviolet A and melanoma: A review SO JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY LA English DT Review ID CUTANEOUS MALIGNANT-MELANOMA; PYRIMIDINE DIMER FORMATION; ALKALINE COMET ASSAY; LOW-DOSE UVA; SUNSCREEN USE; SUN EXPOSURE; CONTACT HYPERSENSITIVITY; WAVELENGTH DEPENDENCE; FLUORESCENT LIGHTS; ACTION SPECTRUM AB The incidence and mortality rates of melanoma have risen for many decades in the United States. Increased exposure to ultraviolet (UV) radiation is generally considered to be responsible. Sunburns, a measure of excess sun exposure, have been identified as a risk factor for the development of melanoma. Because sunburns are primarily due to UVB (280-320 nm) radiation, UVB has been implicated as a potential contributing factor to the pathogenesis of melanoma. The adverse role of UVA (320-400 nm) in this regard is less well studied, and currently there is a great deal of controversy regarding the relationship between UVA exposure and the development of melanoma. This article reviews evidence in the English-language literature that surrounds the controversy concerning a possible role for UVA in the origin of melanoma. Our search found that UVA causes DNA damage via photosensitized reactions that result in the production of oxygen radical species. WA can induce mutations in various cultured cell lines. Furthermore, in two animal models, the hybrid Xiphophorus fish and the opossum (Mondelphis domestica), melanomas and melanoma precursors can be induced with UVA. UVA radiation has been reported to produce immunosuppression in laboratory animals and in humans. Some epidemiologic studies have reported an increase in melanomas in users of sunbeds and sunscreens and in patients exposed to psoralen and UVA (PUVA) therapy. There is basic scientific evidence of the harmful effects of UVA on DNA, cells and animals. Collectively, these data suggest a potential role for UVA in the pathogenesis of melanoma. To date evidence from epidemiologic studies and clinical observations are inconclusive but seem to be consistent with this hypothesis. Additional research on the possible role of UVA in the pathogenesis of melanoma is required. C1 NYU, Sch Med, Ronald O Perelman Dept Dermatol, New York, NY 10016 USA. Mem Sloan Kettering Hosp, New York, NY USA. Brookhaven Natl Lab, New York, NY USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. RP Kopf, AW (reprint author), NYU, Sch Med, Ronald O Perelman Dept Dermatol, 550 1st Ave,H164, New York, NY 10016 USA. RI Berwick, Marianne/E-9608-2010; OI Berwick, Marianne/0000-0001-5062-2180 FU NCI NIH HHS [5P30-CA-16087] NR 106 TC 239 Z9 257 U1 4 U2 42 PU MOSBY, INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0190-9622 J9 J AM ACAD DERMATOL JI J. Am. Acad. Dermatol. PD MAY PY 2001 VL 44 IS 5 BP 837 EP 846 DI 10.1067/mjd.2001.114594 PG 10 WC Dermatology SC Dermatology GA 427VL UT WOS:000168426100017 PM 11312434 ER PT J AU Narushima, T Glaeser, AM AF Narushima, T Glaeser, AM TI High-temperature morphological evolution of lithographically introduced cavities in silicon carbide SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; ION-IMPLANTED SAPPHIRE; CRACK-LIKE FLAWS; MICRODESIGNED INTERFACES; SHAPE EVOLUTION; WULFF SHAPE; SURFACE; ALUMINA; OPPORTUNITIES; KINETICS AB Internal cavities of controlled geometry and crystallography mere introduced in 6H silicon carbide single crystals by combining lithographic methods, ion-beam etching, and solid-state diffusion bonding. The morphologic evolution of these internal cavities (negative crystals) in response to anneals of up to 128 h duration at 1900 degreesC was examined using optical microscopy. Surface energy anisotropy and faceting had a strong influence on the geometric and kinetic characteristics of evolution. Decomposition of {1210} cavity edges into {101x} facets was observed after 16 h anneals, indicating that (1210) faces are not components of the Wulff shape. The shape evolution kinetics of penny-shaped cavities were also investigated. Experimentally observed evolution rates decreased much more rapidly with those predicted by a model in which surface diffusion was assumed to be rate limiting. This suggested that the development of facets and the associated loss of ledges and terraces during the initial stages of evolution resulted in an evolution process limited by the nucleation rate of attachment/detachment sites (ledges) on the facets. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Narushima, T (reprint author), Tohoku Univ, Dept Met, Sendai, Miyagi 9808579, Japan. NR 39 TC 10 Z9 10 U1 0 U2 4 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2001 VL 84 IS 5 BP 921 EP 928 PG 8 WC Materials Science, Ceramics SC Materials Science GA 431XM UT WOS:000168657100003 ER PT J AU Ji, ZQ Haynes, JA Voelkl, E Rigsbee, JM AF Ji, ZQ Haynes, JA Voelkl, E Rigsbee, JM TI Phase formation and stability in reactively sputter deposited yttria-stabilized zirconia coatings SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID BEAM-ASSISTED DEPOSITION; THERMAL BARRIER COATINGS; ZRO2 FILMS; THIN-FILMS; ION-BOMBARDMENT; MICROSTRUCTURE; PARAMETERS; OVERCOATS; SILICON; GROWTH AB Yttria-stabilized zirconia (YSZ) coatings were produced by reactively cosputtering metallic zirconium and yttrium targets in an argon and oxygen plasma using a system with multiple magnetron sputtering sources. Coating crystal structure and phase stability, as functions of Y2O3 content, substrate bias, and annealing temperature, were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM), Results demonstrated that highly (111)-oriented tetragonal and cubic zirconia structures were formed in 2 and 4.5 mol% Y2O3 coatings, respectively, when the coatings were grown with an applied substrate bias, Conversely, coatings deposited with no substrate bias had random tetragonal and cubic structures. XRD analysis of annealed coatings showed that the cubic zirconia in 4.5 mol% Y2O3 coatings exhibited structural stability at temperatures up to 1200 degreesC, Transformation of the tetragonal to monoclinic phase occurred in 2 mol% Y2O3 coating during high-temperature annealing, with the fraction of transformation dependent on bias potential and annealing temperature. C1 Univ Alabama Birmingham, Dept Mat & Mech Engn, Birmingham, AL 35294 USA. Oak Ridge Natl Lab, Ceramic Surface Syst Grp, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. N Carolina State Univ, Raleigh, NC 27695 USA. RP Univ Alabama Birmingham, Dept Mat & Mech Engn, Birmingham, AL 35294 USA. NR 33 TC 11 Z9 12 U1 0 U2 5 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0002-7820 EI 1551-2916 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2001 VL 84 IS 5 BP 929 EP 936 PG 8 WC Materials Science, Ceramics SC Materials Science GA 431XM UT WOS:000168657100004 ER PT J AU Gust, MC Momoda, LA Evans, ND Mecartney, ML AF Gust, MC Momoda, LA Evans, ND Mecartney, ML TI Crystallization of sol-gel-derived barium strontium titanate thin films SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID DIELECTRIC-PROPERTIES; DECOMPOSITION; CAPACITORS; DEPOSITION; CERAMICS AB Microstructural development of thin-film barium strontium titanate (BaxSr1-xTiO3) as a function of strontium concentration and thermal treatment were studied, using transmission electron microscopy (TEM) and X-ray diffractometry (XRD), Thin films, similar to 250 nm thick, were spin-coated onto Pt/Ti/ SiO2/Si substrates, using methoxypropoxide alkoxide precursors, and crystallized by heat-treating at 700 degreesC. All films had the cubic perovskite structure, and their lattice parameters varied linearly with strontium content. Films with higher strontium concentrations had a larger average grain size, In situ TEM heating experiments, combined with differential thermal analysis/thermogravimetric analysis results, suggest that the gel films crystallize as an intermediate carbonate phase, BaxSr1-xTiO2CO3 (with a solid solution range from x 1 to x = 0). Before decomposition at 600 degreesC, this carbonate phase inhibits the formation of the desired perovskite phase. C1 Univ Calif Irvine, Dept Chem & Biochem Engn & Mat Sci, Irvine, CA 92697 USA. Hughes Res Labs, Malibu, CA 90265 USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. RP Gust, MC (reprint author), Univ Calif Irvine, Dept Chem & Biochem Engn & Mat Sci, Irvine, CA 92697 USA. RI Evans, Neal/F-5955-2011 NR 26 TC 45 Z9 49 U1 1 U2 9 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2001 VL 84 IS 5 BP 1087 EP 1092 PG 6 WC Materials Science, Ceramics SC Materials Science GA 431XM UT WOS:000168657100028 ER PT J AU Lake, JA AF Lake, JA TI The fourth generation of nuclear power SO JOURNAL OF THE ATOMIC ENERGY SOCIETY OF JAPAN LA Japanese DT Article C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83401 USA. RP Lake, JA (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83401 USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU ATOMIC ENERGY SOC JAPAN PI TOKYO PA 1-1-13 SHIMBASHI MINATO-KU, TOKYO, 105, JAPAN SN 0004-7120 J9 J ATOM ENERG SOC JPN JI J. At. Energy Soc. Jpn. PD MAY PY 2001 VL 43 IS 5 BP 422 EP 426 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 448XQ UT WOS:000169655600001 ER PT J AU Zhang, X Ross, PN Kostecki, R Kong, F Sloop, S Kerr, JB Striebel, K Cairns, EJ McLarnon, F AF Zhang, X Ross, PN Kostecki, R Kong, F Sloop, S Kerr, JB Striebel, K Cairns, EJ McLarnon, F TI Diagnostic characterization of high power lithium-ion batteries for use in hybrid electric vehicles SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID CARBONATE SOLUTIONS; CURRENT COLLECTORS; SURFACE-CHEMISTRY; CORROSION AB A baseline cell chemistry was identified as a carbon anode, LiNi0.8Co0.2O2 cathode, and diethyl carbonate-ethylene carbonate LiPF6 electrolyte, and designed for high power applications. Nine 18650-size advanced technology development cells were tested under a variety of conditions. Selected diagnostic techniques such as synchrotron infrared microscopy, Raman spectroscopy, scanning electronic microscopy, atomic force microscopy, gas chromatography, etc., were used to characterize the anode, cathode, current collectors and electrolyte taken from these cells. The diagnostic results suggest that the four factors that contribute to the cell power loss are solid electrolyte interphase deterioration and nonuniformity on the anode; morphology changes, increase of impedance, and phase separation on the cathode; pitting corrosion on the cathode current collector; and decomposition of the LiPF6 salt in the electrolyte at elevated temperature. (C) 2001 The Electrochemical Society. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Zhang, X (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 9 TC 133 Z9 135 U1 5 U2 76 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 2001 VL 148 IS 5 BP A463 EP A470 DI 10.1149/1.1362541 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 427TH UT WOS:000168421200011 ER PT J AU Thompson, C Stephenson, GB Eastman, JA Munkholm, A Auciello, O Murty, MVR Fini, P DenBaars, SP Speck, JS AF Thompson, C Stephenson, GB Eastman, JA Munkholm, A Auciello, O Murty, MVR Fini, P DenBaars, SP Speck, JS TI Investigations of chemical vapor deposition of GaN using synchrotron radiation SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID X-RAY-SCATTERING; MOLECULAR-BEAM EPITAXY; BY-LAYER GROWTH; HOMOEPITAXIAL GROWTH; SURFACE-STRUCTURE; ENVIRONMENT; DEPENDENCE; GAN(0001); IMPURITY; SILICON AB We apply synchrotron X-ray analysis techniques to probe the surface structure of GaN films during synthesis by metallorganic chemical vapor deposition (MOCVD). Our approach is to observe the evolution of surface structure and morphology in real-time using grazing incidence X-ray scattering (GIXS). This technique combines the ability of X-rays to penetrate the chemical vapor deposition environment for in situ measurements, with the sensitivity of GIXS to atomic scale structure. Examples are presented from some of our studies of growth modes and surface evolution as a function of process conditions that illustrate the capabilities of synchrotron X-ray analysis during MOCVD growth. We focus on studies of the homoepitaxial growth mode, island coarsening dynamics, and effects of impurities. (C) 2001 The Electrochemical Society. [DOI: 10.1149/1.1366623] All rights reserved. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. RP Thompson, C (reprint author), No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. RI Eastman, Jeffrey/E-4380-2011; Speck, James/H-5646-2011; OI Eastman, Jeff/0000-0002-0847-4265; Thompson, Carol/0000-0003-3832-4855 NR 21 TC 2 Z9 2 U1 0 U2 7 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 2001 VL 148 IS 5 BP C390 EP C394 DI 10.1149/1.1366623 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 427TH UT WOS:000168421200035 ER PT J AU Zhang, XR Pugh, JK Ross, PN AF Zhang, XR Pugh, JK Ross, PN TI Computation of thermodynamic oxidation potentials of organic solvents using density functional theory SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID MOLECULAR-ORBITAL METHODS; PROPYLENE CARBONATE; ELECTROCHEMICAL PROPERTIES; BASIS-SETS; ELECTROLYTE; SALTS; CAPACITORS; BATTERIES; STABILITY; BEHAVIOR AB Ethers and organic carbonates are commonly used as solvents in lithium battery electrolyte. It is important to determine the oxidation potentials of these organic solvents due to the high cathode potential (similar to5 V) in many of these batteries. There are significant variations in the reported oxidation potentials for electrolytes containing these solvents. The factors contributing to the variation include the type of salt used in the electrolyte, composition of the electrode, and a somewhat arbitrary determination of the oxidation potential from the anodic cutoff current. We report here the application of density functional theory (DFT) to calculate solvent oxidation potentials assuming oxidation occurs via one-electron transfer to form the radical cation. No specific ion-ion, ion-solvent, or ion-electrode interactions are included. These values are then compared to the experimental observations. Eleven solvent molecules are studied: 1,2-dimethoxyethane, tetrahydrofuran, 1,3-dioxolane, diethylcarbonate, dimethylcarbonate, ethylmethylcarbonate, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, and catechol carbonate. Optimized geometries of the radical cations correlate well with the fragmentation patterns observed in mass spectrometry. The oxidation potentials of saturated carbonates are calculated to be approximately 1 V higher than the organic ethers, which is consistent with reported literature values. Quantitative comparison with experiment will require more careful measurements to eliminate other oxidation reactions and a standardized procedure for determining the oxidation potential. (C) 2001 The Electrochemical Society. [DOI: 10.1149/1.1362546] All rights reserved. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Zhang, XR (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 37 TC 54 Z9 57 U1 4 U2 53 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 2001 VL 148 IS 5 BP E183 EP E188 DI 10.1149/1.1362546 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 427TH UT WOS:000168421200042 ER PT J AU DeBoo, B Kimball, DF Li, CH Budker, D AF DeBoo, B Kimball, DF Li, CH Budker, D TI Multichannel conical emission and parametric and nonparametric nonlinear optical processes in ytterbium vapor SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID AMPLIFIED SPONTANEOUS EMISSION; 330-NM LASER-PULSES; ATOMIC YTTERBIUM; SODIUM VAPOR; MIXING PROCESS; SUPPRESSION; COMPETITION; EXCITATION; WAVE AB Collimated and conical emissions that appear when Yb vapor is illuminated by light pulses at 262 nm (near the one-photon Yb 6s(2 1)S(0) --> 6s7p P-3(1) transition) are experimentally investigated. Conical emission is observed at multiple wavelengths. Parametric and nonparametric nonlinear optical processes are studied by investigation of the spatial distribution of generated light and the efficiency of light generation as a function of the incident light frequency. (C) 2001 Optical Society of America. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP DeBoo, B (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Budker, Dmitry/F-7580-2016 OI Budker, Dmitry/0000-0002-7356-4814 NR 34 TC 7 Z9 7 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 2001 VL 18 IS 5 BP 639 EP 645 DI 10.1364/JOSAB.18.000639 PG 7 WC Optics SC Optics GA 429ZP UT WOS:000168548800008 ER PT J AU Vigil, SR Kuzyk, MG AF Vigil, SR Kuzyk, MG TI Absolute molecular optical Kerr effect spectroscopy of dilute organic solutions and neat organic liquids SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID PARAMETRIC AMPLIFICATION; QUADRATIC ELECTROABSORPTION; LITHIUM TRIBORATE; SQUARAINE DYES; BARIUM BORATE; SUSCEPTIBILITIES; HYPERPOLARIZABILITY; MECHANISMS; DYNAMICS; POLYMERS AB We report the results of pump-probe optical Kerr effect (OKE) experiments performed on neat solutions of carbon tetrachloride, nitrobenzene, methyl methacrylate monomer, binary solutions of the squaraine dye indole squarylium, and the phthalocyanine dye silicon phthalocyanine-monomethacrylate, respectively, in carbon tetrachloride, and solid solutions of indole squarylium and phthalocyanine-monomethacrylate in poly(methyl methacrylate). Dispersion measurements of the dye solutions were performed in the visible onephoton resonant region of the dyes defined by their linear-absorption spectra. The dyes' third-order molecular susceptibility response gamma (xxxx)(-omega (2); omega (1), -omega (1), omega (2)) in this spectral region is markedly different, with R-{gamma ISQ} > 0 and R{(gamma SiPc)} < 0. Analysis of the dyes' OKE response requires the inclusion of high-lying two-photon states and suggests that a purely electronic mechanism dominates their OKE response. The results are used to calculate the dyes' off-resonant third-order molecular susceptibilities, which are well within the limits predicted by the Thomas-Reiche-Kuhn sum rule [M. G. Kuzyk, Opt Lett. 25, 1183-1185 (2000)]. (C) 2001 Optical Society of America. C1 Washington State Univ, Dept Phys, Pullman, WA 99164 USA. Washington State Univ, Mat Sci Program, Pullman, WA 99164 USA. RP Vigil, SR (reprint author), Sandia Natl Labs, POB 5800,Mail Stop 0328, Albuquerque, NM 87185 USA. OI Kuzyk, Mark/0000-0003-3609-9754 NR 40 TC 11 Z9 11 U1 1 U2 7 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 2001 VL 18 IS 5 BP 679 EP 691 DI 10.1364/JOSAB.18.000679 PG 13 WC Optics SC Optics GA 429ZP UT WOS:000168548800013 ER PT J AU Smith, AV Bowers, MS AF Smith, AV Bowers, MS TI Image-rotating cavity designs for improved beam quality in nanosecond optical parametric oscillators SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID FREQUENCY-CONVERSION; PERFORMANCE; BANDWIDTH AB We show by computer simulation that high beam quality can be achieved in high-energy, nanosecond optical parametric oscillators by use of image-rotating resonators. Lateral walk-off between the signal and the idler beams in a nonlinear crystal creates correlations across the beams in the walk off direction, or equivalently, creates a restricted acceptance angle. These correlations can improve the beam quality in the walk-off plane. We show that image rotation or reflection can be used to improve beam quality in both planes. The lateral walk-off can be due to birefringent walk-off in type II mixing or to noncollinear mixing in type I or type II mixing. (C) 2001 Optical Society of America. C1 Sandia Natl Labs, Dept Lasers Opt & Remote Sensing 1118, Albuquerque, NM 87185 USA. Aculight Corp, Bothell, WA 98011 USA. RP Smith, AV (reprint author), Sandia Natl Labs, Dept Lasers Opt & Remote Sensing 1118, POB 5800, Albuquerque, NM 87185 USA. NR 15 TC 34 Z9 35 U1 1 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 2001 VL 18 IS 5 BP 706 EP 713 DI 10.1364/JOSAB.18.000706 PG 8 WC Optics SC Optics GA 429ZP UT WOS:000168548800016 ER PT J AU Hakovirta, M Lee, DH He, XM Nastasi, M AF Hakovirta, M Lee, DH He, XM Nastasi, M TI Synthesis of fluorinated diamond-like carbon films by the plasma immersion ion processing technique SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID AMORPHOUS-CARBON; COATINGS; IMPLANTATION; DEPOSITION; SURFACES AB The synthesis of fluorinated diamond-like carbon (F-DLC) films was investigated for the first time using the plasma immersion ion processing technique. A pulsed glow discharge plasma was generated at a pressure of 1 Pa from acetylene and hexafluoroethane gas mixtures and the films were deposited on silicon (100) substrates by applying a pulsed bias to the substrate holder. The film hardness, wear resistance and nonwetting properties were found to be strongly dependent on the fluorine content incorporated into the coatings. With an optimum gas ratio, the deposited F-DLC films were found to have nonwetting properties similar to Teflon((R)), but were 10 times harder (8 GPa). (C) 2001 American Vacuum Society. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hakovirta, M (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 17 TC 15 Z9 15 U1 3 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 2001 VL 19 IS 3 BP 782 EP 784 DI 10.1116/1.1368197 PG 3 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 436DY UT WOS:000168922300010 ER PT J AU Hanson, DE Stephens, BC Saravanan, C Kress, JD AF Hanson, DE Stephens, BC Saravanan, C Kress, JD TI Molecular dynamics simulations of ion self-sputtering of Ni and Al surfaces SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID EMBEDDED-ATOM METHOD; FILM GROWTH; CU; DEPOSITION; CU(111); SI; CL AB We present results of molecular dynamics simulations of Ni+ impacting Ni(111) and Al+ impacting Al(111) and amorphous Al surfaces. Sputter yields and sticking probabilities were calculated as a function of ion fluence, impact angle (0-90 degrees) and energy (25-150 eV). We find that the simulated sputter yields are in reasonable agreement with experiments and a commonly used empirical formula. For Al+ impacting at normal incidence, sputter yields were approximately the same for both Al(111) and amorphous Al. The initial penetration depth exhibited a linear dependence with velocity, and was approximately the same for both Al+/Al(111) and Ni+/Ni(111) if the distances were scaled by the lattice constants. The average calculated time between ion impact and atom ejection was less than 25 fs for 100 eV Ni+/Si(111) sputter events. (C) 2001 American Vacuum Society. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Hanson, DE (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 25 TC 19 Z9 20 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 2001 VL 19 IS 3 BP 820 EP 825 DI 10.1116/1.1365134 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 436DY UT WOS:000168922300016 ER PT J AU Chambers, SA Liang, Y Yu, Z Droopad, R Ramdani, J AF Chambers, SA Liang, Y Yu, Z Droopad, R Ramdani, J TI Band offset and structure of SrTiO3/Si(001) heterojunctions SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID RAY PHOTOELECTRON-SPECTROSCOPY; PRECISE DETERMINATION; OXIDES; SRTIO3(100); SILICON; WATER AB We have measured the band offsets and materials properties of epitaxial SrTiO3/Si(001) heterojunctions for both n and p substrates, with and without an interfacial SiO2 layer. The through-air transfer from the growth chamber to the photoemission system results in significant surface hydroxylation and roughening, although the SrTiO3-Si interface is undisturbed. Surface hydroxylation notwithstanding, the structural quality of 20 Angstrom thick epitaxial SrTiO3 on Si(001) is comparable to that of bulk SrTiO3(001). We find valence and conduction band offsets of similar to2.1 and similar to0.0 eV, respectively, independent of doping type and the presence of SiO2. These results are consistent with theoretical band offset predictions based on the electron affinity rule, modified by the presence of an interface dipole. (C) 2001 American Vacuum Society. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Motorola Labs, Phys Sci Res Labs, Tempe, AZ USA. RP Chambers, SA (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. NR 21 TC 82 Z9 84 U1 1 U2 18 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 2001 VL 19 IS 3 BP 934 EP 939 DI 10.1116/1.1365132 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 436DY UT WOS:000168922300034 ER PT J AU Madan, A Barnett, SA Misra, A Kung, H Nastasi, M AF Madan, A Barnett, SA Misra, A Kung, H Nastasi, M TI Structure, stability, and mechanical properties of epitaxial W/NbN superlattices SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID X-RAY-DIFFRACTION; MO/NBN SUPERLATTICES; HARDNESS; MULTILAYERS; INTERFACE; FILMS AB Epitaxial W/NbN superlattices with modulation wavelengths Delta ranging from 1.3 to 25 nm were grown on MgO(001) substrates by de reactive magnetron sputtering in Ar/N-2 mixtures. The epitaxial relationship between the layers is given by W(001)//NbN(001) and W[110]//NbN[100]. X-ray diffraction and Rutherford backscattering results fitted using simulations showed that the superlattices had well-defined planar layers with interface widths of approximate to0.2 nm. Nanoindentation measurements showed superlattice hardnesses as high as 33 GPa compared to 8 for W and 30 fur NbN. The superlattices showed little change in x-ray superlattice reflections or nanoindentation hardness after vacuum annealing up to the highest temperature tested, 1000 degreesC fur G h. Thus, the layers remained intact during annealing, allowing the superlattice hardness enhancement to be retained. (C) 2001 American Vacuum Society. C1 Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Northwestern Univ, Adv Coating Technol Grp, Evanston, IL 60208 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RP Madan, A (reprint author), Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RI Barnett, Scott/B-7502-2009; Misra, Amit/H-1087-2012 NR 25 TC 33 Z9 34 U1 2 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 2001 VL 19 IS 3 BP 952 EP 957 DI 10.1116/1.1365133 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 436DY UT WOS:000168922300036 ER PT J AU Chan, LH Altman, EI Liang, Y AF Chan, LH Altman, EI Liang, Y TI Development of procedures for obtaining clean, low-defect-density Ge(100) surfaces SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID TUNNELING-MICROSCOPY; GE(001); TEMPERATURE; GROWTH AB A repeatable, in situ process was developed for preparing clean, low-defect-density Ge(100) surfaces based on scanning tunneling microscopy (STM), Auger electron spectroscopy (AES), and x-ray photoelectron spectroscopy (XPS) measurements. Surfaces prepared by ion sputtering followed by annealing, wet chemical etching followed by oxidation and thermal desorption of the oxide layer, growth of a Ge buffer layer, and in situ plasma cleaning were compared. The first two methods produced surfaces with no impurities detectable by AES, however, STM images of the surfaces revealed numerous protrusions, vacancies, and other defects. Auger electron spectra and STM images recorded before and after annealing C contaminated surfaces suggested that the protrusions were three-dimensional C clusters formed at elevated temperatures. The low surface to volume ratio of the clusters makes them difficult to detect by either XPS or AES. Although XPS indicated that oxygen plasma treatment effectively removes C from Ge surfaces, images of the plasma treated surfaces still showed the protrusions attributed to C. In contrast, surfaces prepared by Ge buffer layer growth followed by annealing exhibited no protrusions, low-defect densities on the terraces (less than 2% of a monolayer), and evenly spaced terraces that reflect the misorientation of the crystal. Thus, the surfaces prepared by Ge buffer layer growth were determined to be the most suitable for atomic level nucleation and growth studies. (C) American Vacuum Society. C1 Yale Univ, Dept Chem Engn, New Haven, CT 06520 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Chan, LH (reprint author), Yale Univ, Dept Chem Engn, New Haven, CT 06520 USA. NR 21 TC 39 Z9 39 U1 1 U2 14 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 2001 VL 19 IS 3 BP 976 EP 981 DI 10.1116/1.1367264 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 436DY UT WOS:000168922300040 ER PT J AU Mirkarimi, PB Baker, SL Stearns, DG AF Mirkarimi, PB Baker, SL Stearns, DG TI Technique employing gold nanospheres to study defect evolution in thin films SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article AB A technique is described in which commercially available colloidal gold solution is used to deposit monodisperse gold nanospheres with diameters ranging from 20 to 60 nm directly onto silicon wafers. The technique for depositing the gold nanospheres is straightforward and requires Little in terms of infastructure or resources, The wafers containing gold nanospheres are first characterized by techniques such as atomic force,microscopy and transmission electron microscopy, after which they are coated with a thin film and recharacterized. This enables one to quantitatively study the evolution of thin-film defects nucleated by small substrate particles. An example is provided where the technique is used to study the,evolution of defects in Mo/Si multilayer films, which is of significant importance in the development of reticles for extreme ultraviolet lithography. (C) 2001 American Vacuum Society. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Mirkarimi, PB (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 5508, Livermore, CA 94550 USA. NR 7 TC 9 Z9 9 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2001 VL 19 IS 3 BP 628 EP 633 DI 10.1116/1.1364702 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 443WY UT WOS:000169366600005 ER PT J AU Inoue, T Ogletree, DF Salmeron, M AF Inoue, T Ogletree, DF Salmeron, M TI Scanning field-emission force microscopy and spectroscopy of chemical-vapor-deposited carbon field-emission cathodes SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID CVD DIAMOND FILMS; ELECTRON-EMISSION; COLD-CATHODE; THIN-FILMS; EMITTERS AB A scanning-force microscope with an electrically conducting tip was used in both contact and noncontact scanning-polarization force microscopy modes to study the field-emission properties of diamond-like carbon chemical-vapor-deposited films in vacuum. Using the tip as an anode, the emission current and work function were measured with 100 nm lateral resolution. Emission was detected from individual micron-size grains. Large current fluctuations on a ms time scale were observed, correlated with large changes in surface potential, possibly due to charge trapping. There were no significant differences in work function between emitting and nonemitting regions, but the emitting regions showed low conductivity and large band gaps, while the nonemitting regions were either insulating or highly conductive. No asperities were observed at the film-vacuum interface. The current dependence on tip-sample separation suggests that emission occurs below, and not at, the film-vacuum interface. (C) 2001 American Vacuum Society. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Inoue, T (reprint author), Electrotech Lab, 1-1-4 Umezono, Tsukuba, Ibaraki 305, Japan. RI Ogletree, D Frank/D-9833-2016 OI Ogletree, D Frank/0000-0002-8159-0182 NR 24 TC 1 Z9 1 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2001 VL 19 IS 3 BP 675 EP 682 DI 10.1116/1.1370172 PG 8 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 443WY UT WOS:000169366600012 ER PT J AU Auciello, O Tucek, JC Krauss, AR Gruen, DM Moldovan, N Mancini, DC AF Auciello, O Tucek, JC Krauss, AR Gruen, DM Moldovan, N Mancini, DC TI Review of synthesis of low-work function Cu-Li alloy coatings and characterization of the field emission properties for application to field emission devices SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 13th International Vacuum Microlectronics Conference CY AUG 13-17, 2000 CL GUANGZHOU, PEOPLES R CHINA SP Natl Nat Sci Fdn China, Sci & Technol Dept Guangdong Provincial Govt, Guangdong Provincial Assoc Sci & Technol, Educ Dept Guangdong Provincial Govt, Sci & Technol Dept Guangzhou City Govt, KC Wong Educ Fdn, Hong Kong, Amer Vacuum Soc ID ELECTRON-EMISSION; MICROCATHODE ARRAYS; FABRICATION; DEPOSITION; SURFACES; EMITTERS; DIAMOND AB Alkali metals have extremely low-work functions and are therefore expected to result in significant enhancement of the electron emission if they are used as coatings on Mo or Si microtip field emission arrays (FEAs). However, the alkali metals are physically and chemically unstable in layers exceeding a few nanometers in thickness. Maximum enhancement of electron emission occurs for alkali metal layers 0.5-1 monolayer thick, but it is extremely difficult to fabricate and maintain such a thin alkali metal coating. We review here our work of the last three years focused on developing Cu-Li alloy coatings for application to field emitter Spindt-type tip arrays and fabrication of edge emitters with low-voltage high electron emission characteristics for field emission devices. The Cu-Li alloy coatings provide a chemically and thermally stable, self-replenishing, segregated lithium monolayer on the surface of the host Cu layer, resulting in a substantial reduction of the work function of the alloy, compared to that of a thick Li layer or a pure Cu surface. We present results that show a 13-fold reduction in the threshold voltage for electron emission, compared with uncoated Si FEAs. The Cu-Li alloy coatings yielded tip and edge emitters with threshold voltages of 2-10 V/mum, depending of the coating thickness and Li concentration in the alloy. New results are presented that show that we can now coat gated Si tip arrays with Cu-Li alloy films, which results in very low emission voltage. (C) 2001 American Vacuum Society. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Expt Facil Div, Adv Photon Source, Argonne, IL 60439 USA. RP Auciello, O (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 19 TC 8 Z9 8 U1 0 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2001 VL 19 IS 3 BP 877 EP 883 DI 10.1116/1.1375825 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 443WY UT WOS:000169366600048 ER PT J AU Reckless, J Rubin, EM Verstuyft, JB Metcalfe, JC Grainger, DJ AF Reckless, J Rubin, EM Verstuyft, JB Metcalfe, JC Grainger, DJ TI A common phenotype associated with atherogenesis in diverse mouse models of vascular lipid lesions SO JOURNAL OF VASCULAR RESEARCH LA English DT Article DE arteries; atherosclerosis; macrophages; quantitative immunofluorescence; cytokines ID GROWTH-FACTOR-BETA; PLASMINOGEN-ACTIVATOR INHIBITOR; SMOOTH-MUSCLE CELLS; APOLIPOPROTEIN-A-I; TRANSGENIC MICE; TGF-BETA; ENDOTHELIAL-CELLS; ATHEROSCLEROTIC PLAQUES; ADJUVANT TAMOXIFEN; EXPRESSION AB The introduction of a range of different genetic modifications in mice results in altered lipoprotein metabolism and the development of vascular lipid lesions. At present, however, it is unclear to what extent the molecular events underlying lipid lesion formation are similar in these different mouse models of atherosclerosis. The aim of this study was to compare the protein expression pattern of lipid lesions from seven different mouse lines with varying susceptibility to vascular lipid lesion development, to determine to what extent lesions induced by different genetic interventions have a similar composition. The proteins we have measured, using quantitative immunofluorescence, are proteins whose expression is known to be modulated during atherogenesis in humans, including plasminogen activator inhibitor (PAI)-1, transforming growth factor (TGF)-beta1, osteopontin and the macrophage marker CD11b. In all the mice lines we have investigated, PAI-1 was elevated wherever lesions developed. Active TGF-beta was depressed in the vessel wall of mice which developed lipid lesions, particularly in the intima. In contrast, TGF-beta1 antigen (active plus latent TGF-beta1) was increased at lesion sites. Accumulation of osteopontin and, with the marked exception of apolipoprotein(a) transgenic mice, tissue macrophages occurred at sites of lipid deposition in the vessel wall. Each lesion, irrespective of its size and the mouse strain in which it developed, had similar amounts of PAI-1, active TGF-P and osteopontin per unit area of lesion. These data are consistent with a common phenotype accompanying atherogenesis, irrespective of the genetic basis of susceptibility. Copyright (C) 2001 S. Karger AG. Basel. C1 Univ Cambridge, Addenbrookes Hosp, Dept Med, Cambridge CB2 2QQ, England. Univ Cambridge, Dept Biochem, Cambridge CB2 1QW, England. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Reckless, J (reprint author), Univ Cambridge, Addenbrookes Hosp, Dept Med, Box 157,Hills Rd, Cambridge CB2 2QQ, England. NR 53 TC 14 Z9 14 U1 0 U2 2 PU KARGER PI BASEL PA ALLSCHWILERSTRASSE 10, CH-4009 BASEL, SWITZERLAND SN 1018-1172 J9 J VASC RES JI J. Vasc. Res. PD MAY-JUN PY 2001 VL 38 IS 3 BP 256 EP 265 DI 10.1159/000051054 PG 10 WC Physiology; Peripheral Vascular Disease SC Physiology; Cardiovascular System & Cardiology GA 440WM UT WOS:000169199300007 PM 11399898 ER PT J AU Doebling, SW Farrar, CR AF Doebling, SW Farrar, CR TI Estimation of statistical distributions for modal parameters identified from averaged frequency response function data SO JOURNAL OF VIBRATION AND CONTROL LA English DT Article DE modal parameter estimation; frequency response function; statistics AB An algorithm is presented to estimate the statistical distributions of identified modal parameters based on the random errors associated with averaged frequency response function (FRF) estimates. In this study, the modal parameters are assumed to be random variables and the objective is to estimate their distribution statistics (e.g., mean and variance). The algorithm first uses a classical approach to estimate the error on the averaged FRF using the coherence function averaged over an ensemble of measured samples. A Monte Carlo simulation approach is then used to propagate the estimated spectral function errors through the modal parameter identification process. A bootstrap estimate of the modal parameter distribution over the full ensemble of individual measurement samples is used to verify the accuracy of the Monte Carlo algorithm. The statistics of the resulting modal parameter distribution are suitable for use as weights or filtering criteria in model correlation and damage identification schemes. Convergence criteria for determining how many Monte Carlo simulations are required are also presented and discussed. The technique is demonstrated via application to a simulated FRF with known parameter distributions and to experimental data from tests of an in situ bridge. C1 Univ Calif Los Alamos Natl Lab, Engn Anal Grp, ESA, EA, Los Alamos, NM 87545 USA. RP Doebling, SW (reprint author), Univ Calif Los Alamos Natl Lab, Engn Anal Grp, ESA, EA, POB 1663, Los Alamos, NM 87545 USA. NR 11 TC 14 Z9 14 U1 1 U2 4 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 1077-5463 J9 J VIB CONTROL JI J. Vib. Control PD MAY PY 2001 VL 7 IS 4 BP 603 EP 624 DI 10.1177/107754630100700407 PG 22 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 427UG UT WOS:000168423400007 ER PT J AU Nakamura, T Mureithi, NW Chen, SS AF Nakamura, T Mureithi, NW Chen, SS TI Correlation based fluidelastic analysis of tube arrays in two-phase flow SO JSME INTERNATIONAL JOURNAL SERIES B-FLUIDS AND THERMAL ENGINEERING LA English DT Article DE fluidelastic instability; correlation; tube arrays; two-phase flow ID CROSS-FLOW; CYLINDER ARRAYS; INSTABILITY AB In single phase flow, the fluid forces may be considered to be fully correlated along the tube span. This is not the case for two-phase flow. For tube lengths much longer than the typical linear dimension of the two phase flow unit structure (slug, bubble etc.), forces along the tube span are only partially correlated. III this paper, an unsteady Bow model taking into account partial spanwise correlation of the fluid forces is presented. The model is applied to fluidelastic instability analysis of a long span heat exchanger tube model. It is shown that the effect of partial correlation is to reduce the effective net fluid forces which thus raises the effective instability threshold. Another important result is the introduction of additional coupling between modes that would otherwise be uncoupled in the fully correlated case. This has important implications for heat exchanger tubes which have closely spaced modes. Lastly, partial correlation is found to eliminate multiple instability boundaries at low values of the mass-damping parameter; this is a practically significant result. C1 Mitsubishi Heavy Ind Ltd, Takasago R&D Ctr, Takasago, Hyogo, Japan. Kobe Univ, Fac Engn, Nada Ku, Kobe, Hyogo 6578501, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. RP Nakamura, T (reprint author), Mitsubishi Heavy Ind Ltd, Takasago R&D Ctr, 2-1-1 Shinhama,Arai, Takasago, Hyogo, Japan. NR 9 TC 1 Z9 1 U1 0 U2 0 PU JAPAN SOC MECHANICAL ENGINEERS PI TOKYO PA SHINANOMACHI-RENGAKAN BLDG, SHINANOMACHI 35, SHINJUKU-KU, TOKYO, 160-0016, JAPAN SN 1340-8054 J9 JSME INT J B-FLUID T JI JSME Int. J. Ser. B-Fluids Therm. Eng. PD MAY PY 2001 VL 44 IS 2 BP 213 EP 220 DI 10.1299/jsmeb.44.213 PG 8 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 447HQ UT WOS:000169566200005 ER PT J AU Lister, TE Pinhero, PJ AF Lister, TE Pinhero, PJ TI In vivo atomic force microscopy of surface proteins on Deinococcus radiodurans SO LANGMUIR LA English DT Article ID LAYER AB We present in vivo images of the outer cell wall of the bacteria Deinococcus radiodurans using noncontact atomic force microscopy (AFM). High-resolution imaging shows a hexagonal-packed lattice. This lattice is consistent with previous observations of a hexagonally packed intermediate layer from Extracted cell wall material. The ordered hexagonal structures were primarily observed at the interfaces between adjoining bacteria, while rougher, "orange-peel-like" structures were observed in other regions. It is possible that the bacteria were in a dormant state during imaging as the desiccation tolerance of D. radiodurans is well documented. The only previous observations of the HPI layer of D. radiodurans have been performed on chemically extracted S-layers applied to flat substrates. Our report is the first in vivo observation of these structures in D. radiodurans without invasive sample preparation. Additionally, this is the first known report of in vivo observation of bacterial S-layers by AFM. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Pinhero, PJ (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 14 TC 14 Z9 16 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY 1 PY 2001 VL 17 IS 9 BP 2624 EP 2628 DI 10.1021/la001448g PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 426XD UT WOS:000168373000016 ER PT J AU Lerner, S Sasian, J AF Lerner, S Sasian, J TI Parametrically defined surfaces reduce error SO LASER FOCUS WORLD LA English DT Article AB Aspheric optical surfaces defined parametrically can have vastly lower residual errors than traditional polynomial representations, and can take less time to design. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. RP Lerner, S (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave L-495, Livermore, CA 94550 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU PENNWELL PUBL CO PI NASHUA PA 98 SPIT BROOK RD, NASHUA, NH 03062-2801 USA SN 0740-2511 J9 LASER FOCUS WORLD JI Laser Focus World PD MAY PY 2001 VL 37 IS 5 BP 165 EP + PG 3 WC Optics SC Optics GA 432RM UT WOS:000168709500039 ER PT J AU Kotseroglou, T Krejcik, P Emma, P AF Kotseroglou, T Krejcik, P Emma, P TI X-ray FELs may shed light on the molecular world SO LASER FOCUS WORLD LA English DT Article AB A gigawatt-level coherent ultrafast hard x-ray emitter would breathe new life into research in live-cell imaging, phonon excitation, warm dense matter, and even genomics. C1 Illumina Inc, San Diego, CA 92121 USA. Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. RP Kotseroglou, T (reprint author), Illumina Inc, 9390 Town Ctr Dr, San Diego, CA 92121 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU PENNWELL PUBL CO PI NASHUA PA 98 SPIT BROOK RD, NASHUA, NH 03062-2801 USA SN 0740-2511 J9 LASER FOCUS WORLD JI Laser Focus World PD MAY PY 2001 VL 37 IS 5 BP 243 EP + PG 4 WC Optics SC Optics GA 432RM UT WOS:000168709500050 ER PT J AU Logan, CM von Wittenau, AES AF Logan, CM von Wittenau, AES TI Effects of back shield albedo on imagery with a photodiode array using a 9 MV bremsstrahlung spectrum SO MATERIALS EVALUATION LA English DT Article DE portal imaging; flat panel detector; albedo; photodiode array; digital radiography; industrial radiography; nondestructive testing ID CONCRETE; LEAD AB We use a photodiode array with a mammography screen to measure the relative albedo from concrete and lead radiation shielding placed behind the imaging detector. When illuminated by radiation from a 9 MV electron linac, the measured level of radiation backscattered from the concrete shield is 3.33 +/- 0.24 that from the lead shield. This result is consistent with Monte Carlo simulations. The measured backscatter intensity shows the expected inverse distance squared behavior. When the shields are 3 m (10 ft) from the detector, the measured backscatter intensity is at the background level in the detector (eight percent for the given experimental arrangement and for the given energy range). C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Logan, CM (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-333, Livermore, CA 94550 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC NON-DESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 USA SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD MAY PY 2001 VL 59 IS 5 BP 617 EP 620 PG 4 WC Materials Science, Characterization & Testing SC Materials Science GA 430JL UT WOS:000168570700006 ER PT J AU Shin, NS Chang, CH Koo, YM Padmore, H AF Shin, NS Chang, CH Koo, YM Padmore, H TI Synchrotron radiation excited total reflection X-ray fluorescence quantitative analysis of Si wafer by absolute fluorescence intensity calculation SO MATERIALS LETTERS LA English DT Article DE synchrotron radiation; TXRF; ultra trace element quantitative analysis; Si wafer ID SURFACES AB One of the principal industry standard means of measuring surface and near surface wafer contamination is the total reflection X-ray fluorescence (TXRF). Quantification by theoretical calculation of the absolute fluorescence intensity is introduced instead of the use of standards in the TXRF experiment using synchrotron radiation. The surface densities of contaminants in and on Si wafers are determined by comparing calculated results with measured intensities. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pohang Accelerator Lab, Pohang 790784, South Korea. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Shin, NS (reprint author), Pohang Accelerator Lab, Pohang 790784, South Korea. NR 9 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-577X J9 MATER LETT JI Mater. Lett. PD MAY PY 2001 VL 49 IS 1 BP 38 EP 42 DI 10.1016/S0167-577X(00)00338-4 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 436GE UT WOS:000168927500008 ER PT J AU Senkov, ON Chakoumakos, B Jonas, JJ Froes, FH AF Senkov, ON Chakoumakos, B Jonas, JJ Froes, FH TI Effect of temperature and hydrogen concentration on the lattice parameter of beta titanium SO MATERIALS RESEARCH BULLETIN LA English DT Article DE hydrides; metals; neutron scattering; crystal structure; thermal expansion ID ALLOYS AB The lattice parameter of body centered cubic (bcc) beta titanium was determined as a function of temperature and hydrogen concentration using neutron diffraction, In pure titanium, the lattice parameter a = 0.331 nm at 900 degreesC and the thermal expansion coefficient kappa (T) = 13.8 X 10(-6) degreesC(-1) over the temperature range 900 degreesC to 1000 degreesC, The solution of hydrogen in beta titanium is seen to expand the lattice but it has little effect on the thermal expansion coefficient. The dependence of the lattice parameter on atomic percent hydrogen was found to be linear over the hydrogen concentration range 0 to 30 at.%, as expressed by the hydrogen-induced expansion coefficient K-H = 2.1 X 10(-4) nm/at.%H. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Universal Energy Syst Inc, Dayton, OH 45432 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. McGill Univ, Montreal, PQ H3A 2B2, Canada. Univ Idaho, Moscow, ID 83844 USA. RP Senkov, ON (reprint author), Universal Energy Syst Inc, 4401 Dayton Xenia Rd, Dayton, OH 45432 USA. RI Jonas, John/A-2773-2008; Senkov, Oleg/C-7197-2012; Chakoumakos, Bryan/A-5601-2016 OI Jonas, John/0000-0001-7291-6673; Senkov, Oleg/0000-0001-5587-415X; Chakoumakos, Bryan/0000-0002-7870-6543 NR 12 TC 37 Z9 38 U1 5 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-5408 J9 MATER RES BULL JI Mater. Res. Bull. PD MAY-JUN PY 2001 VL 36 IS 7-8 BP 1431 EP 1440 DI 10.1016/S0025-5408(01)00604-3 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 437QD UT WOS:000169004300029 ER PT J AU Wright, SJ AF Wright, SJ TI On reduced convex QP formulations of monotone LCPs SO MATHEMATICAL PROGRAMMING LA English DT Article DE monotone linens complementarity problems; convex quadratic programming; Karush-Kuhn-Tucker conditions AB Techniques for transforming convex quadratic programs (QPs) into monotone linear complementarity problems (LCPa) and vice versa, are well known, We describre a class of LCPs for which a reduced QP formulation - one that has fewer constraints than the "standard" QP formulation - is available. We mention several instances of this class, including the known case in which the coefficient matrix in the LCP is symmetric. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Wright, SJ (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 4 Z9 6 U1 0 U2 1 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0025-5610 J9 MATH PROGRAM JI Math. Program. PD MAY PY 2001 VL 90 IS 3 BP 459 EP 473 DI 10.1007/PL00011431 PG 15 WC Computer Science, Software Engineering; Operations Research & Management Science; Mathematics, Applied SC Computer Science; Operations Research & Management Science; Mathematics GA 434TK UT WOS:000168831800003 ER PT J AU Silverman, E Woloshin, S Schwartz, LM Byram, SJ Welch, HG Fischhoff, B AF Silverman, E Woloshin, S Schwartz, LM Byram, SJ Welch, HG Fischhoff, B TI Women's views on breast cancer risk and screening mammography: A qualitative interview study SO MEDICAL DECISION MAKING LA English DT Article DE breast cancer; decision making; communication ID CARCINOMA IN-SITU AB Background. To promote informed decision making about mammography, clinicians are urged to present women with complete, relevant information about breast cancer and screening. Understanding women's current beliefs may help guide such efforts by uncovering misunderstandings, conceptual gaps, and areas of concern. Objective. The authors sought to learn how women view breast cancer, their personal risk of breast cancer, and how screening mammography affects that risk. Methods. Forty-one open-ended semistructured telephone interviews with women selected from a national database by quota sampling to ensure a wide range In demographics of the participants. Results. Almost all respondents viewed breast cancer as a uniformly progressive disease that begins in a silent curable form (typically found by mammograms) and, unless treated early, invariably grows, spreads, and kills. Some women felt that any abnormality found must be treated, even if it was not malignant. None had heard of potentially nonprogressive cancers, and when informed, most felt that the uncertain prognosis of such lesions reinforced the need to find and treat disease as soon as possible. Women expressed a wide range of views about their personal risk of breast cancer. Although some saw breast cancer as a central threat to their health, many others cited heart disease, other cancers, violence, and trauma as greater concerns. Most recognized the importance of "uncontrollable" factors for breast cancer such as age, sex, family history, and genetics. However, other "controllable" factors with little or no demonstrated link to breast cancer (e.g., smoking, diet, toxic exposures, "bad attitudes") were given equal or greater prominence, suggesting that many women feel considerable personal responsibility for their level of breast cancer risk. Similarly, although women recognized that mammography was not perfect, almost all believed that failure to have mammograms put one at risk for premature and preventable death. When asked how mammography worked, almost all repeated the message that "early detection saves lives," suggesting that advanced cancer (and perhaps most cancer deaths) reflected a failure of early detection. The belief in the benefit of early detection was so strong that some women advocated scaring other women into getting mammograms because it is "better to be safe than sorry." Conclusions. Women view breast cancer as a uniformly progressive disease rarely curable unless caught early. The exaggerated importance many attribute to a variety of controllable factors in modifying personal risk and the "danger" seen in failing to have mammograms may lead women diagnosed with breast cancer to blame themselves. C1 Dept Vet Affairs Med Ctr, VA Outcomes Grp 111B, White River Jct, VT 05009 USA. Dartmouth Coll Sch Med, Ctr Evaluat Clin Sci, Hanover, NH USA. Norris Cotton Canc Ctr, Lebanon, NH USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Batelle Pacific NW Natl Lab, Richland, WA USA. RP Schwartz, LM (reprint author), Dept Vet Affairs Med Ctr, VA Outcomes Grp 111B, White River Jct, VT 05009 USA. NR 17 TC 62 Z9 62 U1 1 U2 7 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0272-989X J9 MED DECIS MAKING JI Med. Decis. Mak. PD MAY-JUN PY 2001 VL 21 IS 3 BP 231 EP 240 DI 10.1177/02729890122062523 PG 10 WC Health Care Sciences & Services; Medical Informatics SC Health Care Sciences & Services; Medical Informatics GA 469EN UT WOS:000170801800008 PM 11386630 ER PT J AU Williams, PT AF Williams, PT TI Physical fitness and activity as separate heart disease risk factors: a meta-analysis SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Article DE cardiorespiratory fitness; physical activity; coronary heart disease risk; cardiovascular disease; public health recommendations; dose-response; exercise; epidemiology; relative risk ID MIDDLE-AGED MEN; UNITED-STATES RAILROAD; ALL-CAUSE MORTALITY; 20-YEAR FOLLOW-UP; LEISURE-TIME; CARDIOVASCULAR-DISEASE; MYOCARDIAL-INFARCTION; VIGOROUS EXERCISE; CORONARY DEATH; ELDERLY MEN AB Objective: Public health policies for physical activity presume that the greatest health benefits are achieved by increasing physical activity among the least active. This presumption is based largely on studies of cardiorespiratory fitness. Tn assess whether studies of cardiorespiratory fitness are germane to physical activity :guidelines, we compared the dose-response relationships between cardiovascular disease endpoints with leisure-time physical activity and fitness from published studies. Data Sources: Twenty-three ses-specific cohorts of physical activity or fitness (representing 1,325,004 person-years of follow-lip. cited in Tables 4-1 and 4-2 of the Surgeon General's Report. Data Synthesis: Relative risks were plotted as a function of the cumulative percentages of the samples when ranked from least fit or active, to most fit or active. To combine study results, a weighted average of the relative risks over the 16 physical activity or seven fitness cohorts was computed at every 5th percentile between 5 and 100%. The analyses show that the risks of coronary heart disease or cardiovascular disease decrease linearly in association with increasing percentiles of physical activity. In contrast, there is a precipitous drop in risk occurring before the 25th percentile of the fitness distribution. As a consequence of this drop, then is a significant difference in the risk reduction associated with being more physically active or physically fit (P less than or equal to 0.04). Conclusions: Being unfit warrants consideration as a risk factor, distinctly from inactivity. and worthy of screening and intervention. Formulating physical activity recommendations oil the basis of fitness studies may inappropriately demote the status of physical fitness as a risk factor while exaggerating the public health benefits of moderate amounts of physical activity. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Williams, PT (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [HL-45652, HL-55640, HL-58621]; NIA NIH HHS [R03 AG032004-01A1, R03 AG032004] NR 59 TC 286 Z9 298 U1 0 U2 19 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2001 VL 33 IS 5 BP 754 EP 761 PG 8 WC Sport Sciences SC Sport Sciences GA 425TF UT WOS:000168307200012 PM 11323544 ER PT J AU Elmer, JW Wong, J Ressler, T AF Elmer, JW Wong, J Ressler, T TI Spatially resolved X-ray diffraction mapping of phase transformations in the heat-affected zone of carbon-manganese steel arc welds SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID TRANSPORT PHENOMENA; FUSION WELDS; MICROSTRUCTURE; EVOLUTION; DIAGRAMS; LASER; FUNDAMENTALS; MACRO AB Phase transformations that occur in the heat-affected zone (HAZ) of gas tungsten are welds in AISI 1005 carbon-manganese steel were investigated using spatially resolved X-ray diffraction (SRXRD) at the Stanford Synchrotron Radiation Laboratory. In situ SRXRD experiments were performed to probe the phases present in the HAZ during welding of cylindrical steel bars. These real-time observations of the phases present in the HAZ were used to construct a phase transformation map that identifies five principal phase regions between the liquid weld pool and the unaffected base metal: (1) alpha -ferrite that is undergoing annealing, recrystallization, and/or grain growth at subcritical temperatures, (2) partially transformed alpha -ferrite co-existing with gamma -austenite at intercritical temperatures, (3) single-phase gamma -austenite at austenitizing temperatures, (4) delta -ferrite at temperatures near the liquidus temperature, and (5) back transformed alpha -ferrite co-existing with residual austenite at subcritical temperatures behind the weld. The SRXRD experimental results were combined with a heat flow model of the weld to investigate transformation kinetics under both positive and negative temperature gradients in the HAZ. Results show that the transformation from ferrite to austenite on heating requires 3 seconds and 158 degreesC of superheat to attain completion under a heating rate of 102 degreesC/s. The reverse transformation from austenite to ferrite on cooling was shown to require 3.3 seconds at a cooling rate of 45 degreesC/s to transform the majority of the austenite back to ferrite; however, some residual austenite was observed in the microstructure as far as 17 mm behind the weld. C1 Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94551 USA. Fritz Haber Inst, Dept Inorgan Chem, D-14195 Berlin, Germany. RP Elmer, JW (reprint author), Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94551 USA. NR 31 TC 52 Z9 52 U1 0 U2 5 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD MAY PY 2001 VL 32 IS 5 BP 1175 EP 1187 DI 10.1007/s11661-001-0127-5 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 429LX UT WOS:000168519600015 ER PT J AU Masarik, J Nishiizumi, K Reedy, RC AF Masarik, J Nishiizumi, K Reedy, RC TI Production rates of cosmogenic helium-3, neon-21, and neon-22 in ordinary chondrites and the lunar surface SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID COSMIC-RAY EXPOSURE; NUCLIDE PRODUCTION; STONY METEOROIDS; NOBLE-GASES; METEORITES; DEPTH; AGES; MODEL; PARTICLES; PROTONS AB The production of He-3, Ne-21, and Ne-22 in meteoroids of various sizes and in the lunar surface was investigated. The LAHET code system, a purely physical model for calculating cosmic-ray particle fluxes, was used to simulate cosmic-ray particle interactions with extraterrestrial matter. We discuss the depth and size dependence of the shielding parameter Ne-22/Ne-21, which is used for reconstruction of pre-atmospheric sizes, depth, and exposure histories. The Ne-22/Ne-21 ratio decreases with increasing depth or pre-atmospheric size but then increases with depth in very large objects. This increase with depth in the Ne-22/Ne-21 ratio means that this ratio is a poor indicator of shielding in some large objects. The dependence of He-3/Ne-21 as function of Ne-22/Ne-21 was also calculated, and differences between the calculations and the Bern line are discussed. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Los Alamos, NM 87545 USA. RP Nishiizumi, K (reprint author), Komensky Univ, Dept Nucl Phys, Mlynska Dolina F-1, SK-84215 Bratislava, Slovakia. OI Reedy, Robert/0000-0002-2189-1303 NR 40 TC 30 Z9 31 U1 0 U2 6 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD MAY PY 2001 VL 36 IS 5 BP 643 EP 650 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 438YF UT WOS:000169081300007 ER PT J AU von Nickisch-Rosenegk, M Brown, WM Boore, JL AF von Nickisch-Rosenegk, M Brown, WM Boore, JL TI Complete sequence of the mitochondrial genome of the tapeworm Hymenolepis diminuta: Gene arrangements indicate that platyhelminths are eutrochozoans SO MOLECULAR BIOLOGY AND EVOLUTION LA English DT Article DE Hymenolepis; tapeworm; phylogeny; mitochondria; evolution; genome ID RIBOSOMAL-RNA; DNA-SEQUENCE; HOX GENES; ORGANIZATION; NEMATODES; PHYLOGENY; FLATWORMS; SUBUNIT; ORIGINS; CODE AB Using "long-PCR," we amplified in overlapping fragments the complete mitochondrial genome of the tapeworm Hymenolepis diminuta (Platyhelminthes: Cestoda) and determined its 13,900-nt sequence. The gene content is the same as that typically found for animal mitochondrial DNA (mtDNA) except that atp8 appears to be lacking, a condition found previously for several other animals. Despite the small size of this mtDNA, there are two large noncoding regions, one of which contains 13 repeats of a 31-nt sequence and a potential stem-loop structure of 25 hp with an 11-member loop. Large potential secondary structures were identified also for the noncoding regions of two other cestode mtDNAs. Comparison of the mitochondrial gene arrangement of H. diminuta with those previously published supports a phylogenetic position of flatworms as members of the Eutrochozoa, rather than placing them basal to either a clade of protostomes or a clade of coelomates. C1 Humboldt Univ, D-10115 Berlin, Germany. Univ Michigan, Dept Biol, Ann Arbor, MI 48109 USA. US DOE, Joint Genome Inst, Walnut Creek, CA USA. Univ Calif Lawrence Livermore Natl Lab, Walnut Creek, CA USA. RP von Nickisch-Rosenegk, M (reprint author), Humboldt Univ, Philippstr 13, D-10115 Berlin, Germany. NR 43 TC 66 Z9 66 U1 0 U2 3 PU SOC MOLECULAR BIOLOGY EVOLUTION PI LAWRENCE PA PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0737-4038 J9 MOL BIOL EVOL JI Mol. Biol. Evol. PD MAY PY 2001 VL 18 IS 5 BP 721 EP 730 PG 10 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 427WA UT WOS:000168427400004 PM 11319256 ER PT J AU Benmore, CJ Tomberli, B Egelstaff, PA Neuefeind, J AF Benmore, CJ Tomberli, B Egelstaff, PA Neuefeind, J TI Quantum effects in the structure of liquid benzene at room temperature SO MOLECULAR PHYSICS LA English DT Article ID X-RAY-DIFFRACTION; MOLECULAR CORRELATION-FUNCTIONS; NEUTRON-DIFFRACTION; WATER AB Structural differences between liquid light (protonated) benzene and heavy (deuterated) benzene at room temperature have been measured using high energy electromagnetic radiation scattering techniques. Intra- and intermolecular effects have been examined, and the main quantum contribution is shown to be intramolecular. This is in contrast to the quantum-effects measured in liquid water at room temperature, which are primarily intermolecular. C1 Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. Univ Guelph, Dept Phys, Guelph, ON N1G 2W1, Canada. DESY, HASYLAB, D-22603 Hamburg, Germany. RP Benmore, CJ (reprint author), Argonne Natl Lab, IPNS, 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 23 TC 6 Z9 6 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD MAY PY 2001 VL 99 IS 10 BP 787 EP 794 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 429BX UT WOS:000168497100006 ER PT J AU Wold, M Lacy, M Lilje, PB Serjeant, S AF Wold, M Lacy, M Lilje, PB Serjeant, S TI Radio-quiet quasar environments at 0.5 <= z <= 0.8 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Review DE galaxies : active; galaxies : clusters : general; quasars : general ID ACTIVE GALACTIC NUCLEI; OPTICAL LUMINOSITY FUNCTION; INTERMEDIATE-REDSHIFT QSOS; SUPERMASSIVE BLACK-HOLES; HOST GALAXIES; LOUD QUASARS; RICH ENVIRONMENTS; CLUSTER ENVIRONMENTS; ELLIPTICAL GALAXIES; CHEMICAL ENRICHMENT AB We quantify the galaxy environments around a sample of 0.5 less than or equal to z less than or equal to 0.8 radio-quiet quasars using the amplitude of the spatial galaxy-quasar correlation function, B-gq. The quasars exist in a wide variety of environments; some sources are located in clusters as rich as Abell class 1-2 clusters, whereas others exist in environments comparable to the field. We find that, on average, the quasars prefer poorer clusters of approximate to Abell class 0, which suggests that quasars are biased tracers of mass compared with galaxies. The mean B-gq for the sample is found to be indistinguishable from the mean amplitude for a sample of radio-loud quasars matched in redshift and optical luminosity. These observations are consistent with recent studies of the hosts of radio-quiet quasars at low to intermediate redshifts, and suggest that the mechanism for the production of powerful radio jets in radio-loud quasars is controlled by processes deep within the active galactic nucleus itself, and is unrelated to the nature of the hosts or their environments. C1 Stockholm Observ, SE-13336 Saltsjobaden, Sweden. Univ Calif Lawrence Livermore Natl Lab, IGPP, Livermore, CA 94550 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Oslo, Inst Theoret Astrophys, N-0315 Oslo, Norway. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Astrophys Grp, London SW7 2BZ, England. RP Wold, M (reprint author), Stockholm Observ, SE-13336 Saltsjobaden, Sweden. RI Lilje, Per/A-2699-2012; OI Lilje, Per/0000-0003-4324-7794 NR 108 TC 44 Z9 44 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 1 PY 2001 VL 323 IS 1 BP 231 EP 247 DI 10.1046/j.1365-8711.2001.04229.x PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 434JE UT WOS:000168810700023 ER PT J AU Schmid, TE Lowe, X Marchetti, F Bishop, J Haseman, J Wyrobek, AJ AF Schmid, TE Lowe, X Marchetti, F Bishop, J Haseman, J Wyrobek, AJ TI Evaluation of inter-scorer and inter-laboratory reliability of the mouse epididymal sperm aneuploidy (m-ESA) assay SO MUTAGENESIS LA English DT Article ID IN-SITU HYBRIDIZATION; BONE-MARROW CELLS; CHROMOSOME-ABNORMALITIES; MULTICOLOR FISH; FLUORESCENCE; MICE; MEN; INDUCTION; OOCYTES; ORIGIN AB The mouse epididymal sperm aneuploidy (mESA) assay using 3-chromosome fluorescence in situ hybridization (FISH) was recently developed for assessing the aneugenic potential of chemicals on male germ cells. This study was designed to identify the major technical factors that affect inter-scorer and inter-laboratory variability of the mESA assay. Two laboratories participated in this study (GSF and Lawrence Livermore National Laboratory, LLNL), Mice (102/E1xC3H/E1) F-1 were exposed in one laboratory (GSF) to vinblastine (VBL; single intraperitoneal injection of 0, 0,5, 1.0 or 2.0 mg/kg), one of the 10 priority compounds of the Commission of the European Communities (CEC) Aneuploidy Program. Twenty-two days later the mESA assay was applied to analyze sperm aneuploidy, In the initial evaluation, small but statistically significant differences were found between the two laboratories in baseline frequencies and there was also disagreement in the determination of a VBL aneuploid effect. Therefore, experiments were conducted to identify the sources of the inter-laboratory differences and technical factors that affected assay reliability and the VBL study was repeated. A harmonization experiment was conducted by bringing the microscope scorers from both laboratories to the same site (LLNL) for a cross-training exercise. Following this exercise, a second group of VBL-treated and control mice were evaluated, and we concluded that VBL is not a sperm aneugen, Our research has identified scoring criteria as the major source of inter-laboratory variation and emphasizes the importance of strict technical controls for the mESA assay, including controlling slide preparations for treatment-induced reductions in sperm count, coding of slides and selection of statistical tests. These considerations are particularly important for the interpretation of small effects (less than or equal to2-fold) on sperm aneuploidy, Our findings suggest that 2-fold differences in frequencies can result from differences among scorers, samples and treatment groups, and are readily within the normal variation for the mESA assay. Such small differences should be viewed with caution until independently confirmed. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. GSF Forschungszentrum Umwelt & Gesundheit GMBH, Inst Saugetiergenet, D-85764 Neuherberg, Germany. NIEHS, Toxicol Lab, Res Triangle Pk, NC 27709 USA. NIEHS, Biostat Branch, Res Triangle Pk, NC 27709 USA. RP Wyrobek, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808,7000 East Ave, Livermore, CA 94550 USA. OI Marchetti, Francesco/0000-0002-9435-4867 FU NIEHS NIH HHS [Y01-ES-10203] NR 42 TC 13 Z9 13 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0267-8357 J9 MUTAGENESIS JI Mutagenesis PD MAY PY 2001 VL 16 IS 3 BP 189 EP 195 DI 10.1093/mutage/16.3.189 PG 7 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA 432EA UT WOS:000168678200002 PM 11320142 ER PT J AU Volkin, E AF Volkin, E TI The discovery of mRNA SO MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH LA English DT Editorial Material DE mRNA; Oak Ridge; history of science; RNA; nucleic acids C1 Oak Ridge Natl Lab, Toxicol & Risk Anal Sect, Div Life Sci, Oak Ridge, TN 37830 USA. RP Volkin, E (reprint author), Oak Ridge Natl Lab, Toxicol & Risk Anal Sect, Div Life Sci, Oak Ridge, TN 37830 USA. NR 17 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1383-5742 J9 MUTAT RES-REV MUTAT JI Mutat. Res.-Rev. Mutat. Res. PD MAY PY 2001 VL 488 IS 2 BP 87 EP 91 DI 10.1016/S1383-5742(00)00061-2 PG 5 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 427LK UT WOS:000168405500001 PM 11344038 ER PT J AU Grant, WF Owens, ET AF Grant, WF Owens, ET TI Chromosome aberration assays in Pisum for the study of environmental mutagens SO MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH LA English DT Review DE Pisum sativum; Pisum fulvum; vicieae; fabaceae; plant bioassay; chromosome aberrations; c-mitosis; antimitotic effects; nuclear DNA amounts; somatic mutations ID GENOME SIZE VARIATION; NUCLEAR-DNA VARIABILITY; GENE-TOX PROGRAM; POLYTENE CHROMOSOMES; SATIVUM LEGUMINOSAE; VICIA-FABA; PEA-SEEDS; BIOASSAYS; INDUCTION; PLANTS AB From a literature survey, 117 chemicals are tabulated that have been assayed in 179 assays for their clastogenic effects in Pisum. Of the 117 chemicals that have been assayed, 65 are reported at giving a positive reaction (i.e. causing chromosome aberrations), 30 positive with a dose response, five borderline positive. Seventeen chemicals gave a negative response. Eighty-one percent of the chemicals gave a definite positive response. A c-mitotic effect was detected from treatment with 17 chemicals. In addition to the above tabulation of chemicals, 39 chemicals have been reported with an antimitotic effect. Thirteen assays have been recorded for five types of radiation, which with the exception of ultrasound reacted positively. The results of assays with 38 chemicals and/or radiations in combined treatments. as well as 15 chemicals and three types of radiations that induce somatic mutations are tabulated, The Pisum sativum (2n = 14) bioassay has been shown to be a very good plant bioassay for assessing chromosome damage both in mitosis and meiosis for somatic mutations induced by chemicals, radiations, and environmental pollutants. For some chemicals, the Pisum assay is not as sensitive in assessing clastogenicity as the Allium assay, although this should be considered in relative terms. Pisum fulvum (2n = 14) has been used in clastogenic studies also, but to a much lesser extent. (C) 2001 Elsevier Science B.V. All rights reserved. C1 McGill Univ, Dept Plant Sci, St Anne De Bellevue, PQ H9X 3V9, Canada. Oak Ridge Natl Lab, Human Genome & Toxicol Grp, Toxicol & Risk Anal Sect, Div Life Sci, Oak Ridge, TN 37830 USA. RP Grant, WF (reprint author), McGill Univ, Dept Plant Sci, Macdonald Campus,POB 4000, St Anne De Bellevue, PQ H9X 3V9, Canada. NR 213 TC 20 Z9 23 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1383-5742 J9 MUTAT RES-REV MUTAT JI Mutat. Res.-Rev. Mutat. Res. PD MAY PY 2001 VL 488 IS 2 BP 93 EP 118 DI 10.1016/S1383-5742(00)00064-8 PG 26 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 427LK UT WOS:000168405500002 PM 11344039 ER PT J AU Macol, CP Tsuruta, H Stec, B Kantrowitz, ER AF Macol, CP Tsuruta, H Stec, B Kantrowitz, ER TI Direct structural evidence for a concerted allosteric transition in Escherichia coli aspartate transcarbamoylase SO NATURE STRUCTURAL BIOLOGY LA English DT Article ID PHOSPHONACETYL-L-ASPARTATE; BISUBSTRATE ANALOG; HEMOGLOBIN; SCATTERING; CATALYSIS; PROTEINS; BINDING; PATHWAY; STATE AB Regulation of protein function, often achieved by allosteric mechanisms, is central to normal physiology and cellular processes. Although numerous models have been proposed to account for the cooperative binding of ligands to allosteric proteins and enzymes, direct structural support has been lacking. Here, we used a combination of X-ray crystallography and small angle X-ray scattering in solution to provide direct structural evidence that the binding of ligand to just one of the six active sites of Escherichia coli aspartate transcarbamoylase induces a concerted structural transition from the T to the R state. C1 Boston Coll, Merkert Chem Ctr, Dept Chem, Chestnut Hill, MA 02467 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Rice Univ, WM Keck Ctr Computat Biol, Dept Biochem & Cell Biol, Houston, TX 77005 USA. RP Kantrowitz, ER (reprint author), Boston Coll, Merkert Chem Ctr, Dept Chem, Chestnut Hill, MA 02467 USA. NR 35 TC 31 Z9 31 U1 0 U2 0 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1072-8368 J9 NAT STRUCT BIOL JI Nat. Struct. Biol. PD MAY PY 2001 VL 8 IS 5 BP 423 EP 426 DI 10.1038/87582 PG 4 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 425WU UT WOS:000168315300014 PM 11323717 ER PT J AU Wlodawer, A Li, M Dauter, Z Gustchina, A Uchida, K Oyama, H Dunn, BM Oda, K AF Wlodawer, A Li, M Dauter, Z Gustchina, A Uchida, K Oyama, H Dunn, BM Oda, K TI Carboxyl proteinase from Pseudomonas defines a novel family of subtilisin-like enzymes SO NATURE STRUCTURAL BIOLOGY LA English DT Article ID NEURONAL CEROID-LIPOFUSCINOSIS; SUBSTRATE-SPECIFICITY; SERINE-PROTEASE; STRUCTURE REFINEMENT; CRYSTAL-STRUCTURE; PEPTIDASE-I; RESOLUTION; IDENTIFICATION; PURIFICATION; INHIBITOR AB The crystal structure of a pepstatin-insensitive carboxyl proteinase from Pseudomonas sp. 101 (PSCP) has been solved by single-wavelength anomalous diffraction using the absorption peak of bromide anions. Structures of the uninhibited enzyme and of complexes with an inhibitor that was either covalently or noncovalently bound were refined at 1.0-1.4 Angstrom resolution. The structure of PSCP comprises a single compact domain with a diameter of similar to 55 Angstrom, consisting of a seven-stranded parallel beta -sheet flanked on both sides by a number of helices. The fold of PSCP is a superset of the subtilisin fold, and the covalently bound inhibitor is linked to the enzyme through a serine residue. Thus, the structure of PSCP defines a novel family of serine-carboxyl proteinases (defined as MEROPS S53) with a unique catalytic triad consisting of Glu 80, Asp 84 and Ser 287. C1 NCI, Prot Struct Sect, Macromol Crystallog Lab, Frederick, MD 21702 USA. NCI, Intramural Res Support Program, SAIC Frederick, Frederick, MD 21702 USA. Brookhaven Natl Lab, Natl Canc Inst, Macromol Crystallog Lab, Synchrotron Radiat Res Sect, Upton, NY 11973 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. Teikyo Univ, Sch Sci & Engn, Dept Biosci, Utsunomiya, Tochigi 3208551, Japan. Kyoto Inst Technol, Fac Text Sci, Dept Appl Biol, Sakyo Ku, Kyoto 6068585, Japan. Univ Florida, Dept Biochem & Mol Biol, Gainesville, FL 32610 USA. RP Wlodawer, A (reprint author), NCI, Prot Struct Sect, Macromol Crystallog Lab, Frederick, MD 21702 USA. EM wlodawer@ncifcrf.gov NR 35 TC 78 Z9 79 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK ST, 9TH FLR, NEW YORK, NY 10013-1917 USA SN 1072-8368 J9 NAT STRUCT BIOL JI Nat. Struct. Biol. PD MAY PY 2001 VL 8 IS 5 BP 442 EP 446 DI 10.1038/87610 PG 5 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 425WU UT WOS:000168315300018 PM 11323721 ER PT J AU Simbulan-Rosenthal, CM Rosenthal, DS Luo, RB Samara, R Jung, M Dritschilo, A Spoonde, A Smulson, ME AF Simbulan-Rosenthal, CM Rosenthal, DS Luo, RB Samara, R Jung, M Dritschilo, A Spoonde, A Smulson, ME TI Poly(ADP-ribosyl)ation of p53 in vitro and in vivo modulates binding to its DNA consensus sequence SO NEOPLASIA LA English DT Article DE poly(ADP-ribose) polymerase; p53; DNA consensus sequence; poly(ADP ribose); DNA binding ID BASE EXCISION-REPAIR; WILD-TYPE P53; ADP-RIBOSYLATION; CELL-DEATH; DEPENDENT TRANSCRIPTION; POLYMERASE-ALPHA; INTERPHASE DEATH; MAMMALIAN-CELLS; TOPOISOMERASE-I; CALF THYMUS AB The tumor-suppressor p53 undergoes extensive poly(ADP-ribosyl)ation early during apoptosis in human osteosarcoma cells, and degradation of poly(ADP-ribose) (PAR) attached to p53 coincides with poly(ADP-ribose)polymerase-1, (PARP-1) cleavage, and expression of p53 target genes. The mechanism by which poly(ADP-ribosyl)ation may regulate p53 function has now been investigated. Purified wild-type PARP-1 catalyzed the poly(ADP-ribosyl) of full-length p53 in vitro. In gel supershift assays, poly(ADP-ribosyl)ation suppressed p53 binding to its DNA consensus sequence; however, when p53 remained unmodified in the presence of inactive mutant PARP-1, it retained sequence-specific DNA binding activity. Poly(ADP-ribosyl)ation of p53 by PARP-1 during early apoptosis in osteosarcoma cells also inhibited p53 interaction with its DNA consensus sequence; thus, poly(ADP-ribosyl)ation may represent a novel means for regulating transcriptional activation by p53 in vivo. C1 Georgetown Univ, Sch Med, Dept Biochem & Mol Biol, Washington, DC 20007 USA. Georgetown Univ, Sch Med, Dept Radiat Med, Washington, DC 20007 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Smulson, ME (reprint author), Georgetown Univ, Sch Med, Dept Biochem & Mol Biol, Basic Sci Bldg,Room 351,3900 Reservoir Rd NW, Washington, DC 20007 USA. FU NCI NIH HHS [P01 CA074175, 1P01 CA74175, CA25344] NR 71 TC 33 Z9 33 U1 0 U2 2 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1522-8002 J9 NEOPLASIA JI Neoplasia PD MAY-JUN PY 2001 VL 3 IS 3 BP 179 EP 188 DI 10.1038/sj.neo.7900155 PG 10 WC Oncology SC Oncology GA 460ZR UT WOS:000170340900002 PM 11494111 ER PT J AU Norby, RJ Kobayashi, K Kimball, BK AF Norby, RJ Kobayashi, K Kimball, BK TI Rising CO2 - future ecosystems - Commentary SO NEW PHYTOLOGIST LA English DT Editorial Material DE free-air CO2 enrichment (FACE); ecosystems; atmospheric CO2; modeling; scale ID AIR CO-2 ENRICHMENT; ELEVATED CO2; FIELD EXPERIMENTS; RESPONSES; FOREST; YIELD AB 'Every beginning biology student knows that photo-synthesis will increase if you give a plant a 'squirt' of CO2 - given enough light, nutrients, and water and a suitable temperature. Logic tells us that if this is so, then more CO2 in the atmosphere should mean more photosynthesis. This, in turn, should mean more yield or accumulated carbon in plants. This logic is fine for beginning biology; unfortunately, nature is not that simple' (Lemon, 1983). C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Natl Inst Agroenvironm Sci, Tsukuba, Ibaraki 3058604, Japan. ARS, US Water Conservat Lab, USDA, Phoenix, AZ 85040 USA. RP Norby, RJ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Norby, Richard/C-1773-2012 OI Norby, Richard/0000-0002-0238-9828 NR 46 TC 26 Z9 33 U1 1 U2 5 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-4930 USA SN 0028-646X J9 NEW PHYTOL JI New Phytol. PD MAY PY 2001 VL 150 IS 2 BP 215 EP 221 DI 10.1046/j.1469-8137.2001.00118.x PG 7 WC Plant Sciences SC Plant Sciences GA 426RE UT WOS:000168361500001 ER PT J AU Lee, TD Tjoelker, MG Ellsworth, DS Reich, PB AF Lee, TD Tjoelker, MG Ellsworth, DS Reich, PB TI Leaf gas exchange responses of 13 prairie grassland species to elevated CO2 and increased nitrogen supply SO NEW PHYTOLOGIST LA English DT Article DE elevated CO2; nitrogen availability; photosynthetic acclimation; functional groups; prairie grassland; stomatal conductance ID CARBON-DIOXIDE ENRICHMENT; RISING ATMOSPHERIC CO2; PHOTOSYNTHETIC ACCLIMATION; CARBOHYDRATE STATUS; FOREST ECOSYSTEMS; PLANT; TEMPERATURE; METAANALYSIS; RESPIRATION; NUTRITION AB Leaf gas exchange responses to elevated CO2 and N are presented for 13 perennial species, representing four functional groups: C-3 grasses, C-4 grasses, legumes, and nonleguminous forbs. Understanding how CO2 and N effects interact is important to predict plant community response to global change. Plants were field-grown in monoculture under current ambient and elevated (560 mu mol mol(-1)) CO2 concentrations (free-air CO2 enrichment), in combination with soil N treatments, for two growing seasons. All species, regardless of functional group, showed pronounced photosynthetic acclimation to elevated CO2, resulting in minimal stimulation of photosynthesis (A) averaging +15% in C-3 grasses, +8% in forbs, +7% in legumes and -2% in C-4 grasses. The effects of CO, and soil N supply did not interact for any leaf traits measured. Elevated CO2 consistently decreased stomatal conductance (g(s)) leading to 40% increase in A/g(s). This substantial acclimation of photosynthesis was greater in magnitude than in most field studies, and was associated with the combined effects of decreased g(s) and decreased leaf N concentrations in response to growth under elevated CO2. C1 Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. Texas A&M Univ, Dept Forest Sci, College Stn, TX 77843 USA. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. RP Lee, TD (reprint author), Univ Minnesota, Dept Forest Resources, 1530 Cleveland Ave N, St Paul, MN 55108 USA. RI Tjoelker, Mark/M-2413-2016; OI Tjoelker, Mark/0000-0003-4607-5238; Ellsworth, David/0000-0002-9699-2272 NR 56 TC 70 Z9 74 U1 3 U2 33 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-4930 USA SN 0028-646X J9 NEW PHYTOL JI New Phytol. PD MAY PY 2001 VL 150 IS 2 BP 405 EP 418 DI 10.1046/j.1469-8137.2001.00095.x PG 14 WC Plant Sciences SC Plant Sciences GA 426RE UT WOS:000168361500018 ER PT J AU Reich, PB Tilman, D Craine, J Ellsworth, D Tjoelker, MG Knops, J Wedin, D Naeem, S Bahauddin, D Goth, J Bengtson, W Lee, TD AF Reich, PB Tilman, D Craine, J Ellsworth, D Tjoelker, MG Knops, J Wedin, D Naeem, S Bahauddin, D Goth, J Bengtson, W Lee, TD TI Do species and functional groups differ in acquisition and use of C, N and water under varying atmospheric CO2 and N availability regimes? A field test with 16 grassland species SO NEW PHYTOLOGIST LA English DT Article DE functional groups; elevated carbon dioxide; nitrogen; N availability; grasses; forbs; legumes; biomass ID SYMBIOTIC N-2 FIXATION; TRIFOLIUM-REPENS L; ELEVATED CO2; GROWTH-RESPONSE; BIOMASS PRODUCTION; NITROGEN GRADIENT; LONG-TERM; ENRICHMENT; PLANTS; PHOTOSYNTHESIS AB To evaluate whether functional groups have a similar response to global change, the responses to CO2 concentration and N availability of grassland species from several functional groups are reported here. Sixteen perennial grassland species from four trait-based functional groups (C-3 grasses, C-4 grasses, non-leguminous forbs, legumes) were grown in field monocultures under ambient or elevated (560 mu mol mol(-1)) CO2 using free-air CO2 enrichment (FACE), in low N (unamended field soil) or high N (field soil +4 g N m(-2) years(-1)) treatments. There were no CO2 x N interactions. Functional groups responded differently to CO2 and N in terms of biomass, tissue N concentration and soil solution N. Under elevated CO2, forbs, legumes and C-3 grasses increased total biomass by 31%, 18%, and 9%, respectively, whereas biomass was reduced in C-4-grass monocultures. Two of the four legume species increased biomass and total plant N pools under elevated CO2, probably due to stimulated N-fixation. Only one species markedly shifted the proportional distribution of below-vs aboveground biomass in response to CO2 or N. Although functional groups varied in responses to CO2 and N, there was also substantial variation in responses among species within groups. These results suggest that current trait-based functional classifications might be useful, but not sufficient, for understanding plant and ecosystem responses to elevated CO2 and N availability. C1 Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. Univ Minnesota, Dept Ecol Evolut & Behav, St Paul, MN 55108 USA. Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. Univ Nebraska, Sch Biol Sci, Lincoln, NE 68583 USA. Univ Nebraska, Sch Nat Resource Sci, Lincoln, NE 68583 USA. Univ Washington, Dept Zool, Seattle, WA 98195 USA. RP Reich, PB (reprint author), Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. RI Craine, Joseph/D-4569-2009; Wedin, David/K-4093-2012; Tjoelker, Mark/M-2413-2016; OI Craine, Joseph/0000-0001-6561-3244; Tjoelker, Mark/0000-0003-4607-5238; Ellsworth, David/0000-0002-9699-2272 NR 43 TC 168 Z9 178 U1 10 U2 98 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-4930 USA SN 0028-646X J9 NEW PHYTOL JI New Phytol. PD MAY PY 2001 VL 150 IS 2 BP 435 EP 448 DI 10.1046/j.1469-8137.2001.00114.x PG 14 WC Plant Sciences SC Plant Sciences GA 426RE UT WOS:000168361500021 ER PT J AU Norby, RJ Todd, DE Fults, J Johnson, DW AF Norby, RJ Todd, DE Fults, J Johnson, DW TI Allometric determination of tree growth in a CO2-enriched sweetgum stand SO NEW PHYTOLOGIST LA English DT Article DE allometry; basal area increment; elevated CO2; forest productivity; free-air CO2 enrichment (FACE); global change; Liquidambar styraciflua (sweetgum); tree growth ID ELEVATED ATMOSPHERIC CO2; BIOMASS PRODUCTION; FUTURE FOREST; ENRICHMENT; RESPONSES; ECOSYSTEM; INCREASES; SEEDLINGS; FIELD AB In a free-air CO2 enrichment (FACE) study, above-ground growth of Liquidambar styraciflua (sweetgum) trees was measured in a closed-canopy stand to test hypotheses about long-term effects of rising [CO2] in a deciduous forest. Allometric relationships were established between above-ground dry mass and basal area, height, taper and wood density for all trees in the 314-m(2) plots. Leaf area index was calculated from leaf litter mass. In the first year of exposure, elevated [CO2] stimulated stand-level aboveground dry matter increment by 33%, but in the second year the growth stimulation was reduced to 15% and was no longer statistically significant. Leaf area index was not affected by CO2 enrichment in either year. These results indicate that large trees that are no longer in an exponential growth phase retain the capacity to respond to elevated [CO2]. The combined 2-yr response of a 24% increase in growth per unit leaf area is consistent with predictions from earlier studies. A longer-term data set is needed to resolve the reason for different responses in the 2 years. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Berea Coll, Berea, KY 40404 USA. Univ Nevada, Reno, NV 89512 USA. RP Norby, RJ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Norby, Richard/C-1773-2012 OI Norby, Richard/0000-0002-0238-9828 NR 36 TC 106 Z9 108 U1 1 U2 20 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-4930 USA SN 0028-646X J9 NEW PHYTOL JI New Phytol. PD MAY PY 2001 VL 150 IS 2 BP 477 EP 487 DI 10.1046/j.1469-8137.2001.00099.x PG 11 WC Plant Sciences SC Plant Sciences GA 426RE UT WOS:000168361500025 ER PT J AU Wullschleger, SD Norby, RJ AF Wullschleger, SD Norby, RJ TI Sap velocity and canopy transpiration in a sweetgum stand exposed to free-air CO2 enrichment (FACE) SO NEW PHYTOLOGIST LA English DT Article DE canopy transpiration; evapotranspiration; FACE; global change; heat pulse probes; Liquidambar styraciflua (sweetgum); sap velocity; water use ID VAPOR-PRESSURE DEFICIT; CARBON-DIOXIDE ENRICHMENT; ELEVATED ATMOSPHERIC CO2; WATER-USE; STOMATAL RESPONSE; PINE FOREST; FLOW; EVAPOTRANSPIRATION; TREES; COTTON AB Canopy transpiration rates, as a major component of forest hydrologic budgets, are reported for 12-yr-old sweetgum (Liquidambar styraciflua) trees growing in a free-air CO2 enrichment (FACE) study in eastern Tennessee, USA. The compensated heat-pulse technique was used to measure rates of sap velocity, and stand transpiration was estimated as a function of measured sap velocity, total stand sapwood area and the fraction of sapwood functional in water transport. Sap velocity averaged 13% less for trees in elevated compared with ambient CO2 concentration. Stand transpiration reached 5.6 and 4.4 mm d(-1) for the ambient and elevated CO2 treatments, respectively. Stratification of the data showed that significant differences in stand transpiration were observed between ambient and elevated CO2 only at mean daily radiation levers > 400 J m(-2) s(-1) and at vapor pressure deficits > 1.0 kPa. These data illustrate that while elevated CO2 may reduce canopy transpiration, the apparent dependency of such an effect on prevailing weather makes detecting a CO2-induced impact on forest water use difficult. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Wullschleger, SD (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Wullschleger, Stan/B-8297-2012; Norby, Richard/C-1773-2012 OI Wullschleger, Stan/0000-0002-9869-0446; Norby, Richard/0000-0002-0238-9828 NR 38 TC 78 Z9 87 U1 2 U2 9 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-4930 USA SN 0028-646X J9 NEW PHYTOL JI New Phytol. PD MAY PY 2001 VL 150 IS 2 BP 489 EP 498 DI 10.1046/j.1469-8137.2001.00094.x PG 10 WC Plant Sciences SC Plant Sciences GA 426RE UT WOS:000168361500026 ER PT J AU Kapitula, T Kevrekidis, P AF Kapitula, T Kevrekidis, P TI Stability of waves in discrete systems SO NONLINEARITY LA English DT Article ID NONLINEAR SCHRODINGER-EQUATION; SOLITARY WAVES; GUIDE ARRAYS; LOCALIZED MODES; INTERNAL-MODES; DARK SOLITONS; DYNAMICS; LATTICES; INSTABILITY; BREATHERS AB The Evans function is a complex analytic function whose zeros correspond to eigenvalues of an associated linear operator. Over the last decade, it has been shown to be a very powerful tool for examining eigenvalue problems of linearized partial differential equations. In this work the Evans function is constructed for differential-difference, i.e. lattice, equations. It is then used to study the stability of waves in Hamiltonian lattice models. In particular, the stability of nonlinear waves for the discrete nonlinear Schrodinger equation, as well as for the discrete sine-Gordon equation, is established. The linear spectrum for each problem is identified, and terms which are exponentially small in the discreteness parameter are quantified. The analytic results are supplemented with detailed numerical simulations. C1 Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. Princeton Univ, Program Appl & Computat Math, Princeton, NJ 08544 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Kapitula, T (reprint author), Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. NR 47 TC 29 Z9 29 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0951-7715 J9 NONLINEARITY JI Nonlinearity PD MAY PY 2001 VL 14 IS 3 BP 533 EP 566 DI 10.1088/0951-7715/14/3/306 PG 34 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 436ET UT WOS:000168924100006 ER PT J AU Bernabei, S Budny, RV Fredrickson, ED Gorelenkov, NN Hosea, JC Phillips, CK White, RB Wilson, JR Petty, CC Pinsker, RI Harvey, RW Smirnov, AP AF Bernabei, S Budny, RV Fredrickson, ED Gorelenkov, NN Hosea, JC Phillips, CK White, RB Wilson, JR Petty, CC Pinsker, RI Harvey, RW Smirnov, AP TI The combined effect of EPMs and TAEs on energetic ion confinement and sawtooth stabilization SO NUCLEAR FUSION LA English DT Article ID INDUCED ALFVEN EIGENMODES; INSTABILITIES; TOKAMAKS AB It is shown for the first time that the chirping Alfven instabilities observed mostly during ICRF heating hale been positively identified as energetic particle modes (EPMs). This has been possible because of a detailed measurement of the q profile with the MSE diagnostic in DIII-D. The EPMs are shown to be the leading cause of the monster sawtooth crash. It is also shown that toroidal Alfen eigenmodes are excited either directly or indirectly by the EPMs and that they cause fast ion Losses. A scenario for the stabilization and the crash of the monster sawteeth and for the degradation of the ICRF heating efficiency at high power is presented. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Gen Atom Co, San Diego, CA USA. CompX, Del Mar, CA USA. Moscow State Univ, Moscow, Russia. RP Bernabei, S (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Smirnov, Alexander /A-4886-2014; White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 14 TC 20 Z9 20 U1 1 U2 6 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 2001 VL 41 IS 5 BP 513 EP 518 DI 10.1088/0029-5515/41/5/304 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 449KB UT WOS:000169682800004 ER PT J AU Hogan, WJ Moses, EI Warner, BE Sorem, MS Soures, JM AF Hogan, WJ Moses, EI Warner, BE Sorem, MS Soures, JM TI The National Ignition Facility SO NUCLEAR FUSION LA English DT Article AB The National Ignition Facility (NIF) is the largest construction project ever undertaken at Lawrence Livermore National Laboratory (LLNL). The NIF consists of 192 40 cm square laser beams and a 10 m diameter target chamber. The NIF is being designed and built by an LLNL led team from Los Alamos National Laboratory, Sandia National Laboratories, the University of Rochester and LLNL. Physical construction began in 1997. The Laser and Target Area Building and the Optics Assembly Building were the first major construction activities, and despite several unforeseen obstacles: the buildings are now 92% complete and have been built on time and within cost. Prototype component development and testing has proceeded in parallel. Optics vendors have installed full scale production lines and have performed prototype production runs. The assembly and integration of the beampath infrastructure have been reconsidered and a new approach has been developed. The article discusses the status of the NIF project and the plans for completion. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Univ Rochester, Rochester, NY USA. RP Hogan, WJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 7 TC 56 Z9 58 U1 1 U2 6 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 2001 VL 41 IS 5 BP 567 EP 573 DI 10.1088/0029-5515/41/5/309 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 449KB UT WOS:000169682800009 ER PT J AU Grisham, LR Kuriyama, M Kawai, M Itoh, T Umeda, N AF Grisham, LR Kuriyama, M Kawai, M Itoh, T Umeda, N CA JT-60U Team TI Improvement of JT-60U negative ion source performance SO NUCLEAR FUSION LA English DT Article AB The several hundred keV neutral beamline which is now operating on JT-60U marks the first usage of negative ion sources to produce high power neutral beams. Because this was such a large advance in the state of the art with respect to all system parameters, many new physical processes appeared during the earlier phases of the beam injection experiments. The physical mechanisms responsible fur these processes have been explored, and solutions have been implemented for some of them, in particular excessive beam stripping, the secular dependence of the are and beam parameters. and the non-uniformity of the plasma illuminating the beam extraction grid. This has reduced the percentage of beam heat loading on the downstream grids by roughly a third and has permitted longer beam pulses at higher powers. Progress is being made in improving the negative ion current density and in coping with the sensitivity of the caesium in the ion sources to oxidation by tiny air or water leaks, and the cathode operation is being altered. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 31101, Japan. RP Grisham, LR (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 11 Z9 11 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 2001 VL 41 IS 5 BP 597 EP 601 DI 10.1088/0029-5515/41/5/312 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 449KB UT WOS:000169682800012 ER PT J AU Shinohara, K Kusama, Y Takechi, M Morioka, A Ishikawa, M Oyama, N Tobita, K Ozeki, T Takeji, S Moriyama, S Fujita, T Oikawa, T Suzuki, T Nishitani, T Kondoh, T Lee, S Kuriyama, M Kramer, GJ Gorelenkov, NN Nazikian, R Cheng, CZ Fu, GY Fukuyama, A AF Shinohara, K Kusama, Y Takechi, M Morioka, A Ishikawa, M Oyama, N Tobita, K Ozeki, T Takeji, S Moriyama, S Fujita, T Oikawa, T Suzuki, T Nishitani, T Kondoh, T Lee, S Kuriyama, M Kramer, GJ Gorelenkov, NN Nazikian, R Cheng, CZ Fu, GY Fukuyama, A CA JT-60 Team TI Alfven eigenmodes driven by Alfvenic beam ions in JT-60U SO NUCLEAR FUSION LA English DT Article ID DIII-D; INSTABILITIES; EXCITATION; TOKAMAKS; STABILITY; PARTICLES; MODES; TFTR AB Instabilities with frequency chirping in the frequency range of Alfven eigenmodes have been found in the domain 0.1% < [(h)] < 1% and v(b)/v(A) similar to 1 with high energy neutral beam injection in JT-60U. One instability with a frequency inside the Alfven continuum spectrum appears and its frequency increases slowly to the toroidicity induced Alfven eigenmode (TAE) gap on the timescale of all equilibrium change (approximate to 200 ms). Other instabilities appear with a frequency inside the TAE gap and their frequencies change very quickly by 10-20 kHz in 1-5 ms. During the period when these fast frequency sweeping (fast FS) modes occur, abrupt large amplitude events (ALEs) often appear with a drop of neutron emission rate and an increase in fast neutral particle fluxes. The loss of energetic lolls increases with a peak fluctuation amplitude of (B) over tilde (theta)/B-theta. An energy dependence of the loss ions is observed and suggests a resonant interaction between energetic ions and the mode. C1 Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 31101, Japan. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Kyoto Univ, Dept Nucl Engn, Kyoto 606, Japan. RP Shinohara, K (reprint author), Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 31101, Japan. RI Cheng, Chio/K-1005-2014; Kikuchi, Mitsuru/O-1036-2015 OI Kikuchi, Mitsuru/0000-0002-5485-8737 NR 23 TC 62 Z9 62 U1 0 U2 4 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 2001 VL 41 IS 5 BP 603 EP 612 DI 10.1088/0029-5515/41/5/313 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 449KB UT WOS:000169682800013 ER PT J AU Tsuji, H Okuno, K Thome, R Salpietro, E Egorov, S Martovetsky, N Ricci, M Zanino, R Zahn, G Martinez, A Vecsey, G Arai, K Ishigooka, T Kato, T Ando, T Takahashi, Y Nakajima, H Hiyama, T Sugimoto, M Hosogane, N Matsukawa, M Miura, Y Terakado, T Okano, J Shimada, K Yamashita, M Isono, T Koizumi, N Kawano, K Oshikiri, M Nunoya, Y Matsui, K Tsuchiya, Y Nishijima, G Kubo, H Shimba, T Hara, E Imahashi, K Uno, Y Ohuchi, T Ohtsu, K Okayama, J Kawasaki, T Kawabe, M Seki, S Takano, K Takaya, Y Tajiri, F Tsutsumi, F Nakamura, T Hanawa, H Wakabayashi, H Shimizu, T Kuramochi, K Omine, T Tamiya, T Harada, J Nishii, K Huguet, M Mitchell, N Bessette, D Minervini, J Vieira, R Michael, P Takayasu, M Bevilacqua, G Maix, RK Manahan, R Jayakumar, RJ Savoldi, L Herz, W Ninomiya, A AF Tsuji, H Okuno, K Thome, R Salpietro, E Egorov, S Martovetsky, N Ricci, M Zanino, R Zahn, G Martinez, A Vecsey, G Arai, K Ishigooka, T Kato, T Ando, T Takahashi, Y Nakajima, H Hiyama, T Sugimoto, M Hosogane, N Matsukawa, M Miura, Y Terakado, T Okano, J Shimada, K Yamashita, M Isono, T Koizumi, N Kawano, K Oshikiri, M Nunoya, Y Matsui, K Tsuchiya, Y Nishijima, G Kubo, H Shimba, T Hara, E Imahashi, K Uno, Y Ohuchi, T Ohtsu, K Okayama, J Kawasaki, T Kawabe, M Seki, S Takano, K Takaya, Y Tajiri, F Tsutsumi, F Nakamura, T Hanawa, H Wakabayashi, H Shimizu, T Kuramochi, K Omine, T Tamiya, T Harada, J Nishii, K Huguet, M Mitchell, N Bessette, D Minervini, J Vieira, R Michael, P Takayasu, M Bevilacqua, G Maix, RK Manahan, R Jayakumar, RJ Savoldi, L Herz, W Ninomiya, A TI Progress of the ITER central solenoid model coil programme SO NUCLEAR FUSION LA English DT Article ID FABRICATION; COMPLETION AB The world's largest pulsed superconducting coil was successfully tested by charging up to 13 T and 46 kA with a stored energy of 640 MJ. The ITER central solenoid (CS) model coil and CS insert coil were developed and fabricated through an international collaboration, and their cooldown and charging tests were successfully carried out by. international test and operation teams. In pulsed charging tests. where the original goal was 0.4 T/s up to 13 T. the CS model coil and the CS insert coil achieved ramp rates to 13 T of 0.6 T/s and 1.2 T/s, respectively. In addition, the CS insert coil was charged and discharged 10 003 times in the 13 T background field of the CS model coil and Ilo degradation of the operational temperature margin directly coming from this cyclic operation was observed. These test results fulfilled ail the goals of CS model coil development by confirming the validity of the engineering design and demonstrating that the ITER coils can now be constructed with confidence. C1 Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. ITER Joint Cent Team, Naka, Ibaraki, Japan. MIT, Cambridge, MA 02139 USA. European Fus Dev Agreement, Garching, Germany. DV Efremov Sci Res Inst Electrophys Apparatus, St Petersburg, Russia. Lawrence Livermore Natl Lab, Livermore, CA USA. ENEA, Ctr Ric Frascati, Frascati, Italy. Politecn Torino, Turin, Italy. Forschungszentrum Karlsruhe, Eggenstein Leopoldshafen, Germany. CEA Cadarache, St Paul Les Durance, France. Ecole Polytech Fed Lausanne, Villigen, Switzerland. Electrotech Lab, Tsukuba, Ibaraki 305, Japan. Seikei Univ, Musashino, Tokyo, Japan. RP Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. EM tsuji@naka.jaeri.go.jp RI Nishijima, Gen/B-8804-2009; OI Nishijima, Gen/0000-0001-7493-0559; Michael, Philip/0000-0003-4906-6169 NR 3 TC 44 Z9 44 U1 2 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0029-5515 EI 1741-4326 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 2001 VL 41 IS 5 BP 645 EP 651 DI 10.1088/0029-5515/41/5/319 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 449KB UT WOS:000169682800019 ER PT J AU Ecklund, S Field, C Mazaheri, G AF Ecklund, S Field, C Mazaheri, G TI A fast luminosity monitor system for PEP II SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE luminosity; radiative bhabha ID LEP AB The PEP II fast luminosity system provides a measurement of luminosity to the control system with a time constant of 0.3 s and fluctuations less than 0.1% for this interval, adequate for use in feedback systems. Continuous visual updates of luminosity are provided. The alignment of the positron beam at the collision point can also be monitored, and there is a visual display of the luminosity associated with each bunch pair in the machine, sampled approximately every 2 s. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. RP Field, C (reprint author), Stanford Linear Accelerator Ctr, Mail Stop 62,2575 Sandhill Rd, Menlo Park, CA 94025 USA. NR 9 TC 7 Z9 10 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 MAY 1 PY 2001 VL 463 IS 1-2 BP 68 EP 76 DI 10.1016/S0168-9002(01)00451-X PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435HK UT WOS:000168871200007 ER PT J AU Ben-Zvi, I Kewisch, J Murphy, J Peggs, S AF Ben-Zvi, I Kewisch, J Murphy, J Peggs, S TI Accelerator physics issues in eRHIC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB The accelerator physics issues associated with adding electron-gold and polarized electron-proton collisions to the RHIC repertoire are discussed. Two scenarios are considered: ring-ring and linac-ring collisions. In the first scenario a third electron ring, possibly made from permanent magnets, is added to the RHIC tunnel. In the second scenario the considerable beam power is recuperated by recycling the beam through the fun energy linac injector. Straw man ring optics are presented, including an integrated spin rotator which provides longitudinally polarized electrons at the interaction points. Electron and ion intensity limitations are investigated, for operations with as many as 2520 bunches. Synchrotron radiation, beam-beam, electron cloud, and cryogenic heat load limits are examined. The implications for new and upgraded ion ring systems are discussed, including electron cooling, RF systems, the ion abort dumps, and injection and extraction kickers. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Peggs, S (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 47 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2001 VL 463 IS 1-2 BP 94 EP 117 DI 10.1016/S0168-9002(01)00471-5 PG 24 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435HK UT WOS:000168871200010 ER PT J AU Wells, DP Jones, JL Yoon, WY Harmon, F AF Wells, DP Jones, JL Yoon, WY Harmon, F TI "Cabinet-safe" study of 1-8 MeV electron accelerators SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE X-ray beams; charged particle beams; beam profile; beam intensity AB The development of "cabinet-safe" accelerator technology for approximate to 1-8 MeV electron LINACs would remove the only major barrier to large-scale "field" applications of these accelerators. These applications range from non-destructive evaluation and assay to radiolytic degradation of hazardous waste. All field applications require large forward dose and very little lateral dose. We investigated the origin, energy, and angular distribution of unwanted lateral radiation dose from two different electron LINACS at three energies. We report on the contributions of various beam parameters to unwanted radiation dose and propose methods to control key beam parameters that significantly contribute to these doses. (C) 2001 Elsevier Science B.V. AII rights reserved. C1 Idaho State Univ, Idaho Accelerator Ctr, Pocatello, ID 83209 USA. Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Idaho State Univ, Idaho Accelerator Ctr, Campus Box 8263, Pocatello, ID 83209 USA. EM wells@physics.isu.edu NR 11 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2001 VL 463 IS 1-2 BP 118 EP 128 DI 10.1016/S0168-9002(01)00519-8 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435HK UT WOS:000168871200011 ER PT J AU Vargas, MA Sheaff, M Vergara, S AF Vargas, MA Sheaff, M Vergara, S TI The development of software to characterize the Fermilab pixel readout chip, FPIX1, for the BTeV experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE solid-state detectors; DAQ; pixel AB Fermilab has designed and assembled a pixel-readout-chip sub-assembly containing five FPIX1 chips with flexible cable interconnections with which to address the technical issues involved in system integration for the proposed BTeV pixel detector. The module contains a total of 14 400 pixel cells that need to be characterized in order to test the entire module. Software has been developed within the LabVIEW framework to control a set of instruments to perform threshold and noise tests on all five readout chips. These tests take only a few hours to run. (C) 2001 Published by Elsevier Science B.V. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. BUAP, Fac Math & Phys Sci, Puebla 72570, Mexico. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. RP Vargas, MA (reprint author), Fermi Natl Accelerator Lab, POB 500,MS 368, Batavia, IL 60510 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2001 VL 463 IS 1-2 BP 331 EP 340 DI 10.1016/S0168-9002(01)00207-8 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435HK UT WOS:000168871200033 ER PT J AU Carr, GL Kramer, SL Murphy, JB Lobo, RPSM Tanner, DB AF Carr, GL Kramer, SL Murphy, JB Lobo, RPSM Tanner, DB TI Observation of coherent synchrotron radiation from the NSLS VUV ring SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE coherent emission; synchrotron radiation; far-infrared source ID LIGHT-SOURCE; EMISSION AB We report the observation of multiparticle coherent emission in the very far infrared from bunched electrons in an electron storage ring. The emission occurs in quasi-periodic bursts, and only when the electron beam current exceeds a threshold value, suggesting an instability-driven modulation of the electron bunch density. For the operating conditions reported, the spectral content of the coherent emission is peaked near a wavelength of 7 mm. This wavelength is much shorter than the nominal electron bunch length, indicating the presence of a density modulation within the bunch. (C) 2001 Published by Elsevier Science B.V. C1 Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. RP Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. EM carr@bnl.gov OI Lobo, Ricardo/0000-0003-2355-6856 NR 19 TC 50 Z9 51 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2001 VL 463 IS 1-2 BP 387 EP 392 DI 10.1016/S0168-9002(01)00521-6 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435HK UT WOS:000168871200039 ER PT J AU Meldrum, A Boatner, LA White, CW AF Meldrum, A Boatner, LA White, CW TI Nanocomposites formed by ion implantation: Recent developments and future opportunities SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT E-MRS Spring Meeting on Materials Science with Ion Beams CY MAY 30-JUN 02, 2000 CL STRASBOURG, FRANCE SP E-MRS DE ion implantation; nanocrystals; optical properties; magnetic properties ID NONLINEAR-OPTICAL PROPERTIES; ATOMIC-FORCE MICROSCOPY; SI NANOCRYSTALS; FUSED-SILICA; ZNS NANOCRYSTALS; AG NANOCRYSTALS; SINGLE-CRYSTALS; METAL COLLOIDS; BEAM SYNTHESIS; GLASS AB Ion implantation is a versatile and powerful technique for forming many types of nanocrystalline precipitates em bedded in the near-surface region of a wide variety of crystalline and amorphous host materials. The unique optical, electronic and magnetic properties of these nanocomposites has stimulated considerable recent research interest. In this review, we discuss recent developments in the field as well as some of the problems that currently hinder the potential applications of nanocomposites formed by ion implantation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Meldrum, A (reprint author), Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. EM ameldrum@ualberta.ca RI Boatner, Lynn/I-6428-2013 OI Boatner, Lynn/0000-0002-0235-7594 NR 65 TC 149 Z9 155 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 2001 VL 178 BP 7 EP 16 DI 10.1016/S0168-583X(00)00501-2 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 444MR UT WOS:000169403700003 ER PT J AU Chason, E Erlebacher, J Aziz, MJ Floro, JA Sinclair, MB AF Chason, E Erlebacher, J Aziz, MJ Floro, JA Sinclair, MB TI Dynamics of pattern formation during low-energy ion bombardment of Si(001) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT E-MRS Spring Meeting on Materials Science with Ion Beams CY MAY 30-JUN 02, 2000 CL STRASBOURG, FRANCE SP E-MRS ID ROUGHENING INSTABILITY; SURFACE-MORPHOLOGY; GE(001) SURFACE; TOPOGRAPHY; SCATTERING; DIFFUSION; ROTATION; SI AB Sputtering of surfaces by collimated, low-energy ion beams results in spontaneous pattern formation in many systems. In order to explore the mechanisms that control the pattern formation, we have used in situ light scattering to measure the evolution of sputtered Si(0 0 1) surfaces. The results are interpreted within a linear instability model originally proposed by R.M. Bradley and J.M.E. Harper [J. Vac. Sci. Technol. A 6 (1988) 2390] that includes the dependence of the sputter yield on the local surface morphology. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brown Univ, Div Engn, Providence, RI 02912 USA. Harvard Univ, Cambridge, MA 02138 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chason, E (reprint author), Brown Univ, Div Engn, Providence, RI 02912 USA. RI Erlebacher, Jonah/A-3231-2010 NR 30 TC 26 Z9 26 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 2001 VL 178 BP 55 EP 61 DI 10.1016/S0168-583X(01)00505-5 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 444MR UT WOS:000169403700008 ER PT J AU Jiang, W Weber, WJ Thevuthasan, S AF Jiang, W Weber, WJ Thevuthasan, S TI Ion implantation and thermal annealing in silicon carbide and gallium nitride SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT E-MRS Spring Meeting on Materials Science with Ion Beams CY MAY 30-JUN 02, 2000 CL STRASBOURG, FRANCE SP E-MRS DE ion implantation; thermal recovery; 6H-SiC; GaN; ion channeling ID IRRADIATION-INDUCED AMORPHIZATION; RADIATION-DAMAGE; GAN; BOMBARDMENT; BEHAVIOR; CERAMICS; DISORDER AB Ion-beam-induced disordering in single crystals of 6H-SiC and single-crystal films of gallium nitride (GaN) has been investigated using ion-channeling methods. Amorphization in GaN requires a dose that is about 30 and 100 times higher than in silicon carbide (SiC) at 180 and 300 K. respectively. Dynamic defect-recovery processes in both materials increase with increasing irradiation temperature. Amorphization in SiC is consistent with a combined direct-impact and defect-stimulated process. Three recovery stages are observed on both the Si and C sublattices under isochronal annealing in Au2+-irradiated 6H-SiC. In GaN, an intermediate saturation state is observed for disordering at the damage peak, which suggests enhanced defect annihilation processes. Implanted Au diffuses towards the surface during implantation at 300 K and undergoes further diffusion into the amorphous surface layer during post-implantation annealing at 870 K. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Weber, WJ (reprint author), Pacific NW Natl Lab, MSIN K8-93,POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 26 TC 4 Z9 4 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 2001 VL 178 BP 204 EP 208 DI 10.1016/S0168-583X(00)00451-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 444MR UT WOS:000169403700039 ER PT J AU Lisic, EC Phillips, M Ensor, D Nash, KL Beets, A Knapp, FF AF Lisic, EC Phillips, M Ensor, D Nash, KL Beets, A Knapp, FF TI Synthesis of a new bisphosphonic acid ligand (SEDP) and preparation of a Re-188-(Sn)SEDP bone seeking radiotracer SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE rhenium-188; bisphosphonate; diphosphonate; HEDP ID NUCLEAR-MEDICINE; HYDROXYETHYLIDENE DIPHOSPHONATE; COMPLEXES; RE-188; METASTASES; GENERATOR; RHENIUM; HEDP AB The new bisphosphonate ligand SEDP (2-sulfonato-1,1-ethylidene bisphosphonic acid) has been synthesized and characterized, including the determination of the protonation constants, and used to form Re-188-(Sn)SEDP from (NaReO4)-Re-188. The title compound Re-188-(Sn)SEDP shows slightly greater bone uptake and less kidney uptake than Re-188-(Sn)HEDP in rat biodistribution studies. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Tennessee Technol Univ, Dept Chem, Cookeville, TN 38501 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Nucl Med Grp, Oak Ridge, TN 37831 USA. RP Lisic, EC (reprint author), Tennessee Technol Univ, Dept Chem, Box 5055, Cookeville, TN 38501 USA. NR 27 TC 14 Z9 15 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD MAY PY 2001 VL 28 IS 4 BP 419 EP 424 DI 10.1016/S0969-8051(00)00205-5 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 440ZH UT WOS:000169206200009 PM 11395315 ER PT J AU Spentzouris, P AF Spentzouris, P TI Short baseline projects SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Europhysics Neutrino Oscillation Workshop CY SEP 09-16, 2000 CL OTRANTO, ITALY ID NEUTRINO OSCILLATIONS; SEARCH AB In a search for nu (mu) --> nu (e) oscillations, the LSND experiment has observed an excess of events which are consistent with an oscillation signal. The KARMEN experiment, which is the only ongoing experiment which can test the LSND hypothesis, does not observe an excess, but also does not cover the full LSND allowed region. In this report, the results of these two experiments are discussed, together with the expectations of the MiniBooNE experiment which has been approved to run at FNAL in 2001. MiniBooNE's goal is to definitely verify or disprove the LSND oscillation hypothesis. Finally, the implications of the experimental techniques developed for current short baseline experiments for a future short baseline program, assuming the verification of the LSND signal, is also discussed. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Spentzouris, P (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 13 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2001 VL 100 BP 163 EP 168 DI 10.1016/S0920-5632(01)01434-7 PG 6 WC Physics, Particles & Fields SC Physics GA 434DW UT WOS:000168800700036 ER PT J AU Spentzouris, P AF Spentzouris, P TI Experiments at Fermilab after minos SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT Europhysics Neutrino Oscillation Workshop CY SEP 09-16, 2000 CL OTRANTO, ITALY ID PHYSICS AB The recent Superkamiokande [1] results for the nu (mu) deficit in the atmospheric neutrino flux have opened an exciting era in neutrino physics. Fermilab has started to investigate the physics potential of a new generation of neutrino experiments based either on muon storage ring neutrino factories or on conventional neutrino beams which use a "super" intense proton source (superbeams). A summary of the status and results from these studies are presented in this note. C1 Fermilab, Batavia, IL 60510 USA. RP Spentzouris, P (reprint author), Fermilab, POB 500, Batavia, IL 60510 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2001 VL 100 BP 204 EP 206 DI 10.1016/S0920-5632(01)01443-8 PG 3 WC Physics, Particles & Fields SC Physics GA 434DW UT WOS:000168800700045 ER PT J AU Bryman, DA Littenberg, L AF Bryman, DA Littenberg, L TI Prospects for measuring K+ -> pi(+)nu(nu)over-bar and K-L(0) -> pi(0)nu(nu)over-bar at BNL SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT International Conference on CP Violation Physics CY SEP 18-22, 2000 CL FERRARA, ITALY SP TPS Grp, Elba srl, Micron Semiconductor, Prontogros Emilia SpA, Cinel, CB Ferrari, ITEM, CAEN Grp ID RARE KAON DECAYS; CP VIOLATION; QUARK MASS; 500 MHZ; MODEL; K+->PI(+)NU(NU)OVER-BAR; K->PI-NU(NU)OVER-BAR; SEARCH; K-L->PI(0)NU(NU)OVER-BAR; SUPERSYMMETRY AB We report on current and future progress on measuring K+ --> pi (+)nu<()over bar> and K-L(0) --> pi (0)nu<()over bar> at the Brookhaven AGS. C1 Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Bryman, DA (reprint author), Univ British Columbia, Dept Phys & Astron, 6224 Agr Rd, Vancouver, BC V6T 1Z1, Canada. NR 34 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2001 VL 99B BP 61 EP 69 DI 10.1016/S0920-5632(01)01363-9 PG 9 WC Physics, Particles & Fields SC Physics GA 429CG UT WOS:000168498000008 ER PT J AU Cooper, PS AF Cooper, PS CA CKM Collaboration TI CKM - Charged Kaons at the Main Injector SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT International Conference on CP Violation Physics CY SEP 18-22, 2000 CL FERRARA, ITALY SP TPS Grp, Elba srl, Micron Semiconductor, Prontogros Emilia SpA, Cinel, CB Ferrari, ITEM, CAEN Grp AB The CKM experiment is a proposal to measure the branching ratio of the rare decay K+ --> pi (+)nu<()over bar> at the Main Injector at Fermilab using a decay in flight technique. The goal is to observe similar or equal to 100 events, for a Standard Model branching ratio of 1 x 10(-10) with a background of less than 10 events. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Cooper, PS (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 5 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2001 VL 99B BP 121 EP 126 DI 10.1016/S0920-5632(01)01370-6 PG 6 WC Physics, Particles & Fields SC Physics GA 429CG UT WOS:000168498000015 ER PT J AU Sciolla, G AF Sciolla, G CA BABAR Collaboration TI The first physics results from BABAR SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT International Conference on CP Violation Physics CY SEP 18-22, 2000 CL FERRARA, ITALY SP TPS Grp, Elba srl, Micron Semiconductor, Prontogros Emilia SpA, Cinel, CB Ferrari, ITEM, CAEN Grp ID CP VIOLATION; B-DECAYS; SEARCH AB The BABAR experiment and the PEP-II accelerator at SLAC started to take data on May 26, 1999. By the time of this conference, the recorded integrated luminosity was 20 fb(-1), of which 8 fb(-1) were analyzed to provide a first set of physics results. This talk reviews the first measurement of sin 2 beta and the study of B meson decays to charmonium modes and 2-body charmless decays. Complementary results were presented by the BABAR Collaboration at this conference and are reviewed in [1]. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Sciolla, G (reprint author), MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. NR 17 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2001 VL 99B BP 135 EP 147 DI 10.1016/S0920-5632(01)01372-X PG 13 WC Physics, Particles & Fields SC Physics GA 429CG UT WOS:000168498000017 ER PT J AU Quinn, HR AF Quinn, HR TI CP violation in B physics - What have we learned, and what comes next? SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT International Conference on CP Violation Physics CY SEP 18-22, 2000 CL FERRARA, ITALY SP TPS Grp, Elba srl, Micron Semiconductor, Prontogros Emilia SpA, Cinel, CB Ferrari, ITEM, CAEN Grp AB This talk is a personal reaction to the Osaka results from the B factories. I review the ranges of Standard Model parameters currently allowed, with the theoretical uncertainties discussed from a skeptical point of view. I comment on the improvements expected both from new measurements and from further theoretical work. MS conclusion is that it is unlikely that the measurement of sin(2 beta) alone will present a clear challenge to the Standard Model, and that, more likely, continued work on both the experimental and theoretical fronts will be needed before ne can assess whether there is new physics required to explain the CP-violating sector of B physics. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Quinn, HR (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2001 VL 99B BP 159 EP 165 DI 10.1016/S0920-5632(01)01374-3 PG 7 WC Physics, Particles & Fields SC Physics GA 429CG UT WOS:000168498000019 ER PT J AU Jaffe, DE AF Jaffe, DE TI Search for CP violation at CLEO SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT International Conference on CP Violation Physics CY SEP 18-22, 2000 CL FERRARA, ITALY SP TPS Grp, Elba srl, Micron Semiconductor, Prontogros Emilia SpA, Cinel, CB Ferrari, ITEM, CAEN Grp ID B-MESON DECAYS; NEUTRAL KAON; B->S-GAMMA; DETECTOR; ASYMMETRIES; MODEL AB Recent results from CLEO on the search for CP violation in beauty and charm meson decays are reviewed. C1 Univ Calif San Diego, La Jolla, CA 92093 USA. RP Jaffe, DE (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 36 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2001 VL 99B BP 174 EP 180 DI 10.1016/S0920-5632(01)01376-7 PG 7 WC Physics, Particles & Fields SC Physics GA 429CG UT WOS:000168498000021 ER PT J AU Leros, N Burnstein, RA Chakravorty, A Chan, A Chen, YC Choong, WS Clarke, K Dukes, C Durandet, C Felix, J Gidal, G Gustafson, HR Ho, C Holmstrom, T Huang, M James, C Jenkins, M Jones, T Kaplan, DM Lederman, LM Longo, MJ Lopez, F Lu, LC Luebke, W Luk, KB Moreno, G Nelson, KS Park, HK Perroud, JP Rajaram, D Rubin, HA Sosa, M Teng, PK Turko, B Volk, J White, C White, SL Zyla, P AF Leros, N Burnstein, RA Chakravorty, A Chan, A Chen, YC Choong, WS Clarke, K Dukes, C Durandet, C Felix, J Gidal, G Gustafson, HR Ho, C Holmstrom, T Huang, M James, C Jenkins, M Jones, T Kaplan, DM Lederman, LM Longo, MJ Lopez, F Lu, LC Luebke, W Luk, KB Moreno, G Nelson, KS Park, HK Perroud, JP Rajaram, D Rubin, HA Sosa, M Teng, PK Turko, B Volk, J White, C White, SL Zyla, P TI HyperCP (E871) Experiment at Fermilab: search for direct CP violation in hyperon decays SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT International Conference on CP Violation Physics CY SEP 18-22, 2000 CL FERRARA, ITALY SP TPS Grp, Elba srl, Micron Semiconductor, Prontogros Emilia SpA, Cinel, CB Ferrari, ITEM, CAEN Grp ID NEUTRAL KAON; INVARIANCE AB The Fermilab HyperCP experiment has accumulated the world's largest sample of Xi (-) and <()over bar>(+) hyperon decays within two running periods in 1997 and 1999. The primary goal of the experiment is to search for direct CP <()over bar>(+) --> <()over bar> pi (+) --> (p) over bar pi (+) pi (+). manifest itself as a difference between the angular distribution of the proton and the antiproton in the Lambda and <()over bar> helicity frame. The amount of data is enough to reach a statistical sensitivity of 1.4 x 10(-4) in the CP violating asymmetry A(Xi Lambda) = (alpha (Xi) alpha (Lambda) - alpha (Xi) alpha (Lambda))/(alpha (Xi) alpha (Lambda) + alpha (<()over bar>) alpha (<()over bar>)). We present an analysis method used to take into A,+ account the slight differences in the production of the Xi (-) and samples. A preliminary result on A(Xi Lambda) at the level of a few 10(-3) and based on a few percent of the 1997 data will be presented. C1 Univ Lausanne, IPHE, CH-1015 Lausanne, Switzerland. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Guanajuato, Leon 37000, Mexico. Univ Virginia, Charlottesville, VA 22901 USA. Univ S Alabama, Mobile, AL 36688 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Acad Sinica, Taipei 11529, Taiwan. IIT, Chicago, IL 60616 USA. RP Leros, N (reprint author), Univ Lausanne, IPHE, CH-1015 Lausanne, Switzerland. NR 12 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2001 VL 99B BP 211 EP 219 DI 10.1016/S0920-5632(01)01380-9 PG 9 WC Physics, Particles & Fields SC Physics GA 429CG UT WOS:000168498000025 ER PT J AU Booth, TE AF Booth, TE TI An approximate Monte Carlo adaptive importance sampling method SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID EXPONENTIAL CONVERGENCE AB It is well known that zero-variance Monte Carlo solutions are possible if an exact importance function is available to bias the random walks. Geometric convergence with iteration has been demonstrated when the importance function estimated on the n'th iteration is used to bias the random walks on the n + 1st iteration, i.e., adaptive importance sampling. Note that geometric convergence with iteration may be less efficient than a nonadaptive Monte Carlo calculation if the time per iteration grows too fast. This paper shows a general method for sampling the zero-variance kernels enabling a Monte Carlo solution that converges inversely with the computer time. C1 Univ Calif Los Alamos Natl Lab, Diagnost Applicat Grp, Los Alamos, NM 87545 USA. RP Booth, TE (reprint author), Univ Calif Los Alamos Natl Lab, Diagnost Applicat Grp, X-5,Mail Stop F663, Los Alamos, NM 87545 USA. NR 6 TC 5 Z9 6 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAY PY 2001 VL 138 IS 1 BP 96 EP 103 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 416ZR UT WOS:000167811000006 ER PT J AU Brown, K Guenther, EA Dingley, KH Cosman, M Harvey, CA Shields, SJ Turteltaub, KW AF Brown, K Guenther, EA Dingley, KH Cosman, M Harvey, CA Shields, SJ Turteltaub, KW TI Synthesis and spectroscopic characterization of site-specific 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine oligodeoxyribonucleotide adducts SO NUCLEIC ACIDS RESEARCH LA English DT Article ID DNA-ADDUCTS; HETEROCYCLIC AMINES; IN-VITRO; COOKED FOODS; CANCER RISK; RAT COLON; CARCINOGEN; PHIP; IDENTIFICATION; NMR AB The aim of the present study is to determine the chemical structure and conformation of DNA adducts formed by incubation of the bioactive form of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhlP), N-acetoxy-PhlP, with a single-stranded 11mer oligodeoxyribonucleotide. Using conditions optimized to give the C8-dG-PhlP adduct as the major product, sufficient material was synthesized for NMR solution structure determination. The NMR data indicate that in duplex DNA this adduct exists in equilibrium between two different conformational states. In the main conformer, the covalently bound PhlP molecule intercalates in the helix, whilst in the minor conformation the PhlP ligand is probably solvent exposed. In addition to the C8-dG-PhlP adduct, at least eight polar adducts are found after reaction of N-acetoxy-PhlP with the oligonucleotide. Three of these were purified for further characterization and shown to exhibit lowest energy UV absorption bands in the range 342-347 nm, confirming the presence of PhlP or PhlP derivative. Accurate mass determination of two of the polar adducts by negative ion MALDI-TOF MS revealed ions consistent with a spirobisguanidino-PhlP derivative and a ring-opened adduct. The third adduct, which has the same mass as the C8-dG-PhlP oligonucleotide adduct, may contain PhlP bound to the N-2 position of guanine. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Turteltaub, KW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. FU NCI NIH HHS [P01 CA055861, CA55861]; NCRR NIH HHS [RR13461, P41 RR013461] NR 36 TC 15 Z9 15 U1 0 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD MAY 1 PY 2001 VL 29 IS 9 BP 1951 EP 1959 DI 10.1093/nar/29.9.1951 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 430ZF UT WOS:000168605800015 PM 11328879 ER PT J AU Meriaudeau, F Wig, A Passian, A Lauret, JP Ferrell, TL AF Meriaudeau, F Wig, A Passian, A Lauret, JP Ferrell, TL TI Multiple gold island layers on a fiber core: a promising sensing device SO OPTICAL ENGINEERING LA English DT Article DE optical fibers; fiber optic sensors; optical index; thin film plasmon ID SURFACE-PLASMON RESONANCE; OPTICAL ABSORBANCE; SENSOR; PARTICLES; FILMS AB Optical fibers are being used more and more as chemical sensors or biosensors. Some of these devices are based on thin film plasmon excitation in which a metal coating is evaporated onto the core or end of an etched optical fiber. A new sensor configuration is presented for detecting liquid adsorbates with different indices of refraction. Instead of exciting surface plasmon waves on a thin film, localized surface plasma waves are excited on metal islands. The fiber is coated with three very thin layers of gold. Each layer is annealed before the next layer is evaporated onto it. This is done to avoid any light leakage, a problem discovered in a prior version with only one gold coating. Different sets of fibers were tested and sensitive and reproducible results for liquids with refraction indices varying from 1.563 to 1.683 were obtained. (C) 2001 Society of Photo-Optical Instrumentation Engineers. C1 Oak Ridge Natl Lab, Photometr Grp, Div Life Sci, Oak Ridge, TN 37830 USA. IUT Le2i, F-71200 Le Creusot, France. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP Meriaudeau, F (reprint author), Oak Ridge Natl Lab, Photometr Grp, Div Life Sci, Bethel Valley Rd, Oak Ridge, TN 37830 USA. NR 17 TC 2 Z9 3 U1 0 U2 1 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD MAY PY 2001 VL 40 IS 5 BP 658 EP 660 DI 10.1117/1.1356404 PG 3 WC Optics SC Optics GA 436QF UT WOS:000168946000003 ER PT J AU Stoner, DL Poloski, AP Johnson, JA Tolle, CR AF Stoner, DL Poloski, AP Johnson, JA Tolle, CR TI Optimization and control of dynamic bioprocesses SO ORGANIC PROCESS RESEARCH & DEVELOPMENT LA English DT Article ID THIOBACILLUS-FERROOXIDANS; FERROUS IRON; SULFUR OXIDATION; ACID PRODUCTION; GROWTH; INHIBITION; CULTURE; BACTERIA; SYSTEM; ORE AB For many applications, such as commodity chemical production, ore leaching, waste treatment, and environmental remediation, bioprocesses can be less expensive, more energy-efficient, and more environmentally friendly than conventional processes. The key to effective implementation of bioprocesses is rational design, optimization, and process control. We are applying the tools of intelligent systems to develop supervisory systems for the optimization and control of continuous, dynamic, and uncharacterized bioprocesses. We have designed, built, and evaluated hierarchical hardware and software systems for the control of microbial oxidation of soluble iron in a continuous stirred tank reactor. The supervisory control module uses stochastic learning to determine what system parameters (i.e., pH, dilution rate, and temperature) should be, based on the state of the system. An expert-based flow-rate controller optimizes reactor performance for each set of system parameters. Theoretically, high reactor conversion can be obtained much faster by varying these multiple parameters simultaneously as opposed to the traditional method of varying a single parameter at any given instance. C1 Idaho Natl Engn & Environm Lab, Dept Biotechnol, MS 2203, Idaho Falls, ID 83415 USA. RP Stoner, DL (reprint author), Idaho Natl Engn & Environm Lab, Dept Biotechnol, MS 2203, POB 1625,2525 Fremont Ave, Idaho Falls, ID 83415 USA. NR 34 TC 1 Z9 1 U1 2 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1083-6160 J9 ORG PROCESS RES DEV JI Org. Process Res. Dev. PD MAY-JUN PY 2001 VL 5 IS 3 BP 299 EP 307 DI 10.1021/op0100091 PG 9 WC Chemistry, Applied; Chemistry, Organic SC Chemistry GA 435DY UT WOS:000168863200018 ER PT J AU Sun, XH He, DM Cameron, KW Luo, Y AF Sun, XH He, DM Cameron, KW Luo, Y TI Adaptive multivariate regression for advanced memory system evaluation: application and experience SO PERFORMANCE EVALUATION LA English DT Article DE performance evaluation; advanced memory system; computer architecture; statistical method; scalability; benchmarking ID SCALABILITY; MACHINE; MODEL AB Recent advances in latency hiding techniques have made performance evaluation of memory hierarchies a more difficult task. Applications compiled for a particular architecture may be executed on vastly different memory hierarchy implementations. There is a need for performance analysis techniques that provide methods for understanding the interaction between applications and a given memory hierarchy. In this paper, we present a statistical approach to performance analysis of advanced memory hierarchy implementations. The method involves the utilization of previously available statistical analysis techniques coupled with scalability analysis. The result is a novel step-wise approach to understanding the hierarchical memory performance of scientific applications. We apply the method to several scientific applications of interest to the accelerated strategic computing initiative (ASCI) over the SGI machines PowerChallenge and Origin 2000. Results indicate some codes are statistically identical in memory performance, while others vary greatly. Furthermore, some codes do not take advantage of the performance enhancements to the memory system found in the Origin 2000. (C) 2001 Elsevier Science B.V. All rights reserved. C1 IIT, Dept Comp Sci, Chicago, IL 60616 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sun, XH (reprint author), IIT, Dept Comp Sci, Chicago, IL 60616 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-5316 J9 PERFORM EVALUATION JI Perform. Eval. PD MAY PY 2001 VL 45 IS 1 BP 1 EP 18 DI 10.1016/S0166-5316(00)00051-1 PG 18 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA 433TJ UT WOS:000168775600001 ER PT J AU Datta-Gupta, A Kulkarni, KN Yoon, S Vasco, DW AF Datta-Gupta, A Kulkarni, KN Yoon, S Vasco, DW TI Streamlines, ray tracing and production tomography: generalization to compressible flow SO PETROLEUM GEOSCIENCE LA English DT Article DE inverse problem; travel time; ray tracing; streamlines ID PARAMETER-IDENTIFICATION; SOLUTE TRANSPORT; INVERSE PROBLEM; WAVE-EQUATION; POROUS-MEDIA; SIMULATION AB We exploit an analogy between streamlines and seismic ray tracing to develop an efficient formalism for integrating dynamic data into high-resolution reservoir models. Utilizing concepts from asymptotic ray theory in seismic and diffusive electromagnetic imaging, we generalize the streamline approach to compressible flow. A 'diffusive' streamline time-of-flight is introduced for transient pressure calculations. Production data integration is carried out in a manner analogous to seismic tomography and waveform imaging. The power and versatility of our approach is illustrated using synthetic examples that utilize transient pressure, tracer and multiphase production history. A field example from a heterogeneous carbonate reservoir demonstrates the practical feasibility of our approach. C1 Texas A&M Univ, Dept Petr Engn, College Stn, TX 77843 USA. Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Datta-Gupta, A (reprint author), Texas A&M Univ, Dept Petr Engn, College Stn, TX 77843 USA. RI Vasco, Donald/I-3167-2016 OI Vasco, Donald/0000-0003-1210-8628 NR 37 TC 17 Z9 17 U1 0 U2 0 PU GEOLOGICAL SOC PUBL HOUSE PI BATH PA UNIT 7, BRASSMILL ENTERPRISE CENTRE, BRASSMILL LANE, BATH BA1 3JN, AVON, ENGLAND SN 1354-0793 J9 PETROL GEOSCI JI Petrol. Geosci. PD MAY PY 2001 VL 7 SI SI BP S75 EP S86 PG 12 WC Geosciences, Multidisciplinary SC Geology GA 441RQ UT WOS:000169243600009 ER PT J AU Jiao, S Hirsch, PB Perovic, DD AF Jiao, S Hirsch, PB Perovic, DD TI Climb/glide dislocation sources at low-misfit GexSi1-x-Si(001) interfaces SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID HETEROGENEOUS NUCLEATION; EPITAXY; STRAIN AB Detailed analysis of Burgers vectors and line directions has been carried out on three types of dislocation defect (called X, Y and single loops) formed in low-misfit GexSi(1x)/Si(001) heterostructures, grown under conditions of planar interface growth. The X and Y defects originate from small prismatic vacancy half-loops nucleated at visible precipitates at the strained-layer-Si substrate interface. The single-loop defects also originate from small vacancy character half-loops usually nucleated at the interface but also sometimes within the strained layer. After growth, none of the dislocations lies in glide planes, and all three dislocation structures have to be transformed into glissile configurations before they can generate strain-relieving dislocations. The mechanism controlling this sessile/glissile transformation is climb by vacancy absorption. This corresponds to the nucleation stage for the generation of misfit dislocations observed by Houghton and is consistent with the experimental results of Stirpe et al. who found a reduction in the nucleation rates during rapid thermal anneals after Si irradiation at room temperature of the as-grown samples. The paper discusses the driving forces controlling the formation of the observed structures, and their sessile-glissile transformation. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Oxford, Dept Mat, Oxford OX1 3PH, England. Univ Toronto, Dept Met & Mat Sci, Toronto, ON M5S 3E4, Canada. RP Jiao, S (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 2 Z9 2 U1 0 U2 3 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2001 VL 81 IS 5 BP 1041 EP 1064 PG 24 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 433KC UT WOS:000168757700003 ER PT J AU Mitchell, TE Baskes, MI Chen, SP Hirth, JP Hoagland, RG AF Mitchell, TE Baskes, MI Chen, SP Hirth, JP Hoagland, RG TI Stacking-fault energy and yield stress asymmetry in molybdenum disilicide SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID MOSI2 SINGLE-CRYSTALS; MECHANICAL-PROPERTIES; PLASTIC-DEFORMATION; TEMPERATURE; DISLOCATIONS; ALLOYS; METALS; SLIP AB Stacking-fault energies in MoSi2 due to shear along [331] have been calculated by ab-initio and modified embedded-atom method (MEAM) calculations. The results are used to investigate the configurations of 1/2 [331] dislocations and their mobility. Shear of 1/6 [331] in the {103} plane of MoSi2 produces an antiphase boundary (APB) whose geometry, called APB(1), is different from that produced by 1/6 [331] in the opposite direction, APB(2). MEAM calculations show that APB(1) is stable while both types of calculation show that APB(2) is unstable. Both ab-initio and MEAM calculations show that there is a stable fault close to APB(2) with a displacement of about 1/8 [331] in the same direction. The calculations also show that there is a stable fault in the {110} plane with a displacement of 1/4 [111]. The identical fault is produced by a shear of 1/4 [331]. There is good agreement between the fault energies calculated by the two methods and also with the experimental value (200-370 mJ m(2)). The agreement between the calculated fault energies in the {013} plane is not so good. One factor is that the relaxation procedures are different; the MEAM method has more flexibility as well as a larger number of atoms, possibly explaining why it gives lower stable fault energies. The {103} planes have an unusual five-layer ABCDE stacking sequence with successive planes offset by 1/5 [301]. Shear of 1/10 [351] in the correct direction gives a low-energy fault with Mo atoms surrounded by the correct number (ten) of Si nearest neighbours. This vector is close to the 1/8 [331] shear that produces a stable fault and may explain its low calculated energy. Various dissociated configurations of 1/2 [331] dislocations are considered on the basis of 1/6 [331], 1/8 [331], 1/4 [331] and 1/10 [351] partials. All can have asymmetrical arrangements which will respond differently to the direction of the applied stress, explaining why {103} [331] slip is much easier for crystals compressed along [100] than along [001]. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Mitchell, TE (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Hoagland, Richard/G-9821-2012 NR 28 TC 10 Z9 10 U1 0 U2 5 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2001 VL 81 IS 5 BP 1079 EP 1097 PG 19 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 433KC UT WOS:000168757700005 ER PT J AU Bulatov, VV Justo, JF Cai, W Yip, S Argon, AS Lenosky, T de Koning, M de la Rubia, TD AF Bulatov, VV Justo, JF Cai, W Yip, S Argon, AS Lenosky, T de Koning, M de la Rubia, TD TI Parameter-free modelling of dislocation motion: the case of silicon SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID 90-DEGREES PARTIAL DISLOCATION; ELECTRON-MICROSCOPY; MOBILITY; GLIDE; CORE; SHUFFLE; KINKS; OPTIMIZATION; ENERGIES; PHASES AB In silicon and other materials with a high Peierls potential, dislocation motion takes place by nucleation and propagation of kink pairs. The rates of these unit processes are complex unknown functions of interatomic interactions in the dislocation core, stress and temperature. This work is an attempt to develop a quantitative physical description of dislocation motion in silicon based on understanding of the core structure and the energetics of core mechanisms of mobility. Atomistic simulations reveal multiple and complex kink mechanisms of dislocation translation; however, this complexity can be rationalized through the analysis of a straight kink-free dislocation, based on symmetry-breaking arguments. Further reduction is achieved by observing that the energetics of kink mechanisms is scaled by a single parameter, the energy required to break a bond in the core. To obtain accurate values of this energy we perform density functional calculations that lead us to conclude that the low mobility of the 30 degrees dislocation results from its high bond-breaking energy. Armed with the knowledge of kink mechanisms, we develop a kinetic Monte Carlo model that makes direct use of the atomistic data as the material-defining input and predicts the dislocation velocity on the length and time scales accessible to experiments. This provides the connection between the atomistic aspects of the dislocation core and the mobility behaviour of single dislocations. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. MIT, Cambridge, MA 02139 USA. Univ Sao Paulo, Inst Phys, BR-05508 Sao Paulo, Brazil. RP Bulatov, VV (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI de Koning, Maurice/E-1115-2012 OI de Koning, Maurice/0000-0002-0035-4170 NR 43 TC 56 Z9 59 U1 1 U2 11 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2001 VL 81 IS 5 BP 1257 EP 1281 PG 25 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 433KC UT WOS:000168757700015 ER PT J AU Yang, LH Soderlind, P Moriarty, JA AF Yang, LH Soderlind, P Moriarty, JA TI Accurate atomistic simulation of (a/2) < 111 > screw dislocations and other defects in bcc tantalum SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID CENTERED-CUBIC METALS; GENERALIZED PSEUDOPOTENTIAL THEORY; QUANTUM-MECHANICAL CALCULATION; TRANSITION-METALS; INTERATOMIC POTENTIALS; BOUNDARY-CONDITIONS; SINGLE-CRYSTALS; GREENS-FUNCTION; AB-INITIO; MO AB The fundamental atomic-level properties of (a/2) [111] screw dislocations and other defects in bcc Ta have been simulated by means of new quantum-based multi-ion interatomic potentials derived from the model generalized pseudopotential theory (MGPT). The potentials have been validated in detail using a combination of experimental data and ab-initio electronic structure calculations on ideal shear strength, vacancy and self-interstitial formation and migration energies, grain-boundary atomic structure and generalized stacking-fault energy (gamma) surfaces. Robust and accurate two- and three-dimensional Green's function (GF) techniques have been used to relax dynamically the boundary forces during the dislocation simulations. The GF techniques have been implemented in combination with a spatial domain decomposition strategy, resulting in a parallel MGPT atomistic simulation code that increases computational performance by two orders of magnitude. Our dislocation simulations predict a degenerate core structure with threefold symmetry for Ta, but one that is nearly isotropic and only weakly polarized at ambient pressure. The degenerate nature of the core structure leads to possible antiphase defects (APDs) on the dislocation line as well as multiple possible dislocation kinks and kink pairs. The APD and kink energetics are elaborated in detail in the low-stress limit. In this limit, the calculated stress-dependent activation enthalpy for the lowest-energy kink pair agrees well with that currently used in mesoscale dislocation dynamics simulations to model the temperature-dependent single-crystal yield stress. In the high-stress limit, the calculated Peierls stress displays a strong orientation dependence under pure shear and uniaxial loading conditions, with an antitwinning-twinning ratio of 2.29 for pure shear {211}- [111] loading. C1 Lawrence Livermore Natl Lab, Phys & Adv Technol Directorate, Livermore, CA 94551 USA. RP Lawrence Livermore Natl Lab, Phys & Adv Technol Directorate, Livermore, CA 94551 USA. EM lyang@llnl.gov NR 47 TC 93 Z9 94 U1 4 U2 30 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2001 VL 81 IS 5 BP 1355 EP 1385 PG 31 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 433KC UT WOS:000168757700021 ER PT J AU Chapline, G AF Chapline, G TI Quantum mechanics as self-organized information fusion SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article AB Attention is drawn to the similarity between quantum mechanics and finding the simplest explanation for the data from an array of sensors. In particular, comparison of the Durbin-Willshaw approach to solving the travelling salesman problem with the Feynman path integral for motion of a charged particle in a magnetic field suggests that quantum mechanics might be of practical use both for integrating multiple measurements and for solving nonpolynomial (NP)-complete problems. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chapline, G (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 2 Z9 2 U1 1 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD MAY PY 2001 VL 81 IS 5 BP 541 EP 549 DI 10.1080/13642810110048416 PG 9 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 437EH UT WOS:000168977300008 ER PT J AU Pizarro, SA Sauer, K AF Pizarro, SA Sauer, K TI Spectroscopic study of the light-harvesting protein C-phycocyanin associated with colorless linker peptides SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID CIRCULAR-DICHROISM SPECTRA; EXCITATION-ENERGY TRANSFER; RESOLVED RATE CONSTANTS; UV-VISIBLE ABSORPTION; MASTIGOCLADUS-LAMINOSUS; CYANOBACTERIAL PHYCOBILISOMES; CHROMOPHORE-PROTEIN; ROD SUBSTRUCTURES; POLYPEPTIDES; RESOLUTION AB C-Phycocyanin (PC) trimers associated with linker polypeptides were isolated from the phycobilisome (PBS) rods of Synechococcus sp, PCC 7002. L-X(Y) refers to a linker polypeptide (L) having an apparent mass of Y kDa, located at position X in the phycobilisome where X can be R (rod), C (core) or RC (rod-core junction). Measurements of the absorption, fluorescence and excitation anisotropy of PC trimer, pC(.)L(R)(32.3) and (PCLRC28.5)-L-. complexes document the spectroscopic modulation of each linker polypeptide on the PC chromophores, The difference spectra between the PC trimer and the PC-linker complexes show that although the effect induced by the linker polypeptides is qualitatively similar in behavior, the extent of the modulation is greater in (PCLRC28.5)-L-.. Measurements taken at 77 K show that a red-wavelength component of the PC trimer absorption-fluorescence spectra is the target of the linker's influence and that this component is altered to a greater extent by L-RC(28.5). In addition the 77 K absorbance of the PC trimer resolves band features that are consistent with an excitonic coupling interaction between neighboring alpha 84 and beta 84 chromophores, These band features are also evident in the absorbance of (PCLR32.3)-L-. but are absent in (PCLRC28.5)-L-. indicating that L-RC(28.5) may be perturbing the coupling interaction established in the PC trimer alpha 84-beta 84 chromophore pairs. Structurally, the linker polypeptide should disrupt the C-3 symmetry in the central cavity of the associated phycobiliprotein and this asymmetric interaction should serve to guide the transfer of excitation energy along PBS rods toward the core elements. C1 LBNL, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Sauer, K (reprint author), LBNL, Phys Biosci Div, 1 Cyclotron Rd,Bldg 3, Berkeley, CA 94720 USA. NR 37 TC 17 Z9 18 U1 0 U2 7 PU AMER SOC PHOTOBIOLOGY PI AUGUSTA PA BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 USA SN 0031-8655 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD MAY PY 2001 VL 73 IS 5 BP 556 EP 563 DI 10.1562/0031-8655(2001)073<0556:SSOTLH>2.0.CO;2 PG 8 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 430MV UT WOS:000168578400017 PM 11367580 ER PT J AU Cunningham, CE Petrovic, C Lapertot, G Bud'ko, SL Laabs, F Straszheim, W Finnemore, DK Canfield, PC AF Cunningham, CE Petrovic, C Lapertot, G Bud'ko, SL Laabs, F Straszheim, W Finnemore, DK Canfield, PC TI Synthesis and processing of MgB2 powders and wires SO PHYSICA C LA English DT Article DE MgB2 powder; MgB2 wire; synthesis AB Sintered powders and wires of superconducting MgB2 have been fabricated under a variety of conditions in order to determine details of the diffusion of the Mg into B and to study the types of defects that arise during growth. For samples prepared by exposure of boron to Mg vapor at 950 degreesC, the conversion of particles of less than 100 mum size to MgB2 is complete in about 2 h. The lattice parameters of the MgB2 phase determined from X-ray are independent of the starting stoichiometry and the time of reaction. Wire segments of MgB2 with very little porosity have been produced by reacting 141 mum diameter boron fibers in an atmosphere of excess Mg vapor at 950 degreesC. Defects in the reacted fibers are predominantly voids left as the boron is converted to MgB2. Published by Elsevier Science B.V. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Finnemore, DK (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. RI LAPERTOT, Gerard/B-3354-2008; Petrovic, Cedomir/A-8789-2009; Canfield, Paul/H-2698-2014 OI Petrovic, Cedomir/0000-0001-6063-1881; NR 11 TC 33 Z9 34 U1 3 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 2001 VL 353 IS 1-2 BP 5 EP 10 DI 10.1016/S0921-4534(01)00397-5 PG 6 WC Physics, Applied SC Physics GA 433TF UT WOS:000168775300002 ER PT J AU Solovyov, VF Wiesmann, HJ Suenaga, M AF Solovyov, VF Wiesmann, HJ Suenaga, M TI Growth rate limiting mechanisms of YBa2Cu3O7 films manufactured by ex situ processing SO PHYSICA C LA English DT Article DE YBCO; coated conductors; barium fluoride process ID THIN-FILMS; DEPOSITION; SRTIO3 AB YBa2Cu3O7 films were fabricated on SrTiO3 substrates using the BaF2 ex situ process. Precursor films 1, 3 and 5 mum thick were processed in an atmospheric pressure reactor using a gas mixture of oxygen, nitrogen and water vapor. The films were processed at different water vapor pressures and it was observed that the him growth rate was independent of film thickness and proportional to the square root of the water vapor pressure. The dependence of the film growth rate on film area was also investigated for film areas varying from 10 to 160 mm(2). Surprisingly, it was observed that the growth rate was inversely proportional to square root of the area of the him. A theoretical model is developed and applied to the experimental results presented in this paper. The model correctly predicts the inverse square root dependence of the film growth rate on sample area. In addition, it predicts that it will be difficult to process long samples, such as tapes, in simple reactor geometries. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Div Mat & Chem Sci, Upton, NY 11973 USA. RP Solovyov, VF (reprint author), Brookhaven Natl Lab, Div Mat & Chem Sci, Bldg 480, Upton, NY 11973 USA. RI Solovyov, Vyacheslav/A-7724-2009; OI Solovyov, Vyacheslav/0000-0003-1879-9802 NR 15 TC 60 Z9 60 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 2001 VL 353 IS 1-2 BP 14 EP 22 DI 10.1016/S0921-4534(00)01652-X PG 9 WC Physics, Applied SC Physics GA 433TF UT WOS:000168775300004 ER PT J AU Semenov, YG Yokoi, H Kakudate, Y Takeyama, S Tozer, SW Kim, Y Wojtowicz, T Karczewski, G Kossut, J AF Semenov, YG Yokoi, H Kakudate, Y Takeyama, S Tozer, SW Kim, Y Wojtowicz, T Karczewski, G Kossut, J TI Interface local spin states in a CdTe/(Cd, Mn)Te quantum well SO PHYSICA E LA English DT Article; Proceedings Paper CT 1st International Conference on the Physics and Applications of Spin-Related Phenomena in Semiconductors (PASPS 2000) CY SEP 13-15, 2000 CL SENDAI, JAPAN SP Tohoku Univ, Res Inst Elect Commun, Commemorat Assoc Japan World Exposit (1970), Sendai Tourism & Convent Bur, Murata Sci Fdn DE diluted magnetic semiconductors; interface; quantum wells AB Magneto-photoluminescence spectra obtained experimentally for a 1.9 nm thick CdTe quantum well with semi-magnetic barriers of Cd1-xMnxTe (x = 0.24) in the range of a magnetic field B = 0-50 T and applied pressure up to 1.5 GPa have been analyzed through the interface delta -potential model. In the model, the interface potential is expressed as A sigma delta (z +/- L-w/2), where a is the spin projection +/-1/2 and L-w is the quantum well width. Our results show that the amplitude of the interface potential A is saturated at 15 T and is not changed up to 50 T. This behavior is described well by the modified Brillouin function, which suggests that the magnetic ions in the interface region are isolated rather than clustered, in contrast to those: in the barrier layers. The potential amplitude A is found to be enhanced by the pressure. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Inst Mat & Chem Res, Tsukuba, Ibaraki 3058565, Japan. Polish Acad Sci, Inst Phys, PL-02668 Warsaw, Poland. Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Chiba Univ, Dept Phys, Inage Ku, Chiba 2638522, Japan. Natl Acad Sci Ukraine, Inst Semicond Phys, UA-252650 Kiev, Ukraine. RP Yokoi, H (reprint author), Natl Inst Mat & Chem Res, 1-1 Higashi, Tsukuba, Ibaraki 3058565, Japan. RI Kossut, Jacek/K-9481-2016; Wojtowicz, Tomasz/A-2887-2017 OI Kossut, Jacek/0000-0001-6165-3169; NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD MAY PY 2001 VL 10 IS 1-3 BP 340 EP 343 DI 10.1016/S1386-9477(01)00112-6 PG 4 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 435VL UT WOS:000168902800072 ER PT J AU Itoh, KM Haller, EE AF Itoh, KM Haller, EE TI Isotopically engineered semiconductors - new media for the investigation of nuclear spin related effects in solids SO PHYSICA E LA English DT Article; Proceedings Paper CT 1st International Conference on the Physics and Applications of Spin-Related Phenomena in Semiconductors (PASPS 2000) CY SEP 13-15, 2000 CL SENDAI, JAPAN SP Tohoku Univ, Res Inst Elect Commun, Commemorat Assoc Japan World Exposit (1970), Sendai Tourism & Convent Bur, Murata Sci Fdn DE nuclear spin; silicon; germanium; superlattice ID MAGNETIC-RESONANCE; SUPERLATTICES; GROWTH AB We report on the growth and characterization of isotopically controlled silicon bulk single crystals and germanium superlattice structures in which position and concentration of nuclear spins can be controlled intentionally. The isotopically controlled semiconductor structures enable a wide variety of nuclear-spin related studies involving nuclear-magnetic-resonance and electron-spin-resonance spectroscopy. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Keio Univ, Dept Appl Phys & PhysicoInformat, Yokohama, Kanagawa 2238522, Japan. Keio Univ, JST, PRESTO, Yokohama, Kanagawa 2238522, Japan. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Itoh, KM (reprint author), Keio Univ, Dept Appl Phys & PhysicoInformat, 3-14-1 Hiyoshi, Yokohama, Kanagawa 2238522, Japan. RI Itoh, Kohei/C-5738-2014 NR 8 TC 12 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1386-9477 J9 PHYSICA E JI Physica E PD MAY PY 2001 VL 10 IS 1-3 BP 463 EP 466 DI 10.1016/S1386-9477(01)00138-2 PG 4 WC Nanoscience & Nanotechnology; Physics, Condensed Matter SC Science & Technology - Other Topics; Physics GA 435VL UT WOS:000168902800098 ER PT J AU Abdallah, MA Cocke, CL AF Abdallah, MA Cocke, CL TI Comment on "Importance of electron time-of-flight measurements in momentum imaging of saddle-point electron emission" SO PHYSICAL REVIEW A LA English DT Letter ID CONTINUUM ELECTRONS; HE AB A recent paper by Irby [Phys. Rev. A 60, 1135 (1999)] analyzes the effect of using calculated, rather than measured, values of the electron time-of-fight in soft electron imaging. This paper creates the impression that the analysis used by Abdallah et al. [Phys. Rev. A 56, 2000 (1997)] might be suspect and that the saddle-point shifts observed in that paper might be in en or. In fact, the analysis used by Abdallah et nl. is almost exact, as is shown in this comment, and the conclusions reached in that paper were correct. C1 Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA. RP Abdallah, MA (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2001 VL 63 IS 5 BP art. no. EP 056701 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 430RJ UT WOS:000168589100133 ER PT J AU Tanabe, S Watanabe, S Sato, N Matsuzawa, M Yoshida, S Reinhold, C Burgdorfer, J AF Tanabe, S Watanabe, S Sato, N Matsuzawa, M Yoshida, S Reinhold, C Burgdorfer, J TI Siegert-pseudostate representation of quantal time evolution: A harmonic oscillator kicked by periodic pulses SO PHYSICAL REVIEW A LA English DT Article ID DYNAMICAL STABILIZATION; ATOM; APPROXIMATION; PROPAGATION AB Finiteness of the computational resources is a hindrance to representing the lime evolution of an infinitely extended system. Several numerical techniques are available for mimicking the nonboundedness of the system despite the restricted Hilbert space of the employed expansion basis set. We present a formulation based on the outgoing-wave Siegert pseudostates. A harmonic oscillator exposed to a periodic train of impulsive pulses ("kicks") demonstrate the efficiency of the Siegert method. C1 Univ Electrocommun, Dept Appl Phys & Chem, Chofu, Tokyo 1828585, Japan. Vienna Univ Technol, Inst Theoret Phys, A-1040 Vienna, Austria. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP Tanabe, S (reprint author), Univ Electrocommun, Dept Appl Phys & Chem, 1-5-1 Chofu Ga Oka, Chofu, Tokyo 1828585, Japan. OI Reinhold, Carlos/0000-0003-0100-4962 NR 17 TC 15 Z9 16 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2001 VL 63 IS 5 BP art. no. EP 052721 DI 10.1103/PhysRevA.63.052721 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 430RJ UT WOS:000168589100078 ER PT J AU Young, L Dunford, RW Kanter, EP Krassig, B Southworth, SH Bonham, RA Lykos, P Morong, C Timm, A Carney, JPJ Pratt, RH AF Young, L Dunford, RW Kanter, EP Krassig, B Southworth, SH Bonham, RA Lykos, P Morong, C Timm, A Carney, JPJ Pratt, RH TI Corrections to the usual x-ray scattering factors in rare gases: Experiment and theory SO PHYSICAL REVIEW A LA English DT Article ID CORRELATED WAVE-FUNCTIONS; CROSS-SECTIONS; LITHIUM AB The ratio of the total x-ray scattering from Ne to that from He has been determined for photon energies in the range 4-15 keV at scattering angles of 45 and 90 degrees (corresponding to momentum transfers ranging from 0.90 to 5.69 a.u.). An arrangement of two gas cells in series was employed, allowing simultaneous measurements on both gases at the same scattering angle, which eliminates possible errors due to fluctuating beam intensity. Pairs of measurements corresponding to the same momentum transfer (at momentum transfers of 1.67 and 3.08 a.u.) but to different energies, provide a direct test of the corrections to the (momentum-transfer-dependent) form-factor incoherent-scattering-factor theory. These corrections include the anomalous p.A contributions, which are found to be important. We also consider corrections to the usual approximations made within the inelastic A(2) theory (the incoherent-scattering factor, using closure approximation, and the impulse approximation, assuming free-particle kinematics with a given momentum distribution). In these cases an incoherent-scattering-factor treatment is generally adequate, while anomalous scattering factor corrections to form factors are needed for elastic scattering. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. IIT, Dept Biol Chem & Phys Sci, Chicago, IL 60616 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. RP Young, L (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 16 TC 13 Z9 13 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2001 VL 63 IS 5 BP art. no. EP 052718 DI 10.1103/PhysRevA.63.052718 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 430RJ UT WOS:000168589100075 ER PT J AU Zhang, HL Sampson, DH Inal, MK AF Zhang, HL Sampson, DH Inal, MK TI Ionization to specific magnetic sublevels bg an electron beam: Application to the effect of inner-shell ionization on the polarization of Se24+ lines SO PHYSICAL REVIEW A LA English DT Article ID HIGHLY-CHARGED IONS; X-RAY-LINES; CIRCULAR-POLARIZATION; COLLISION STRENGTHS; IMPACT EXCITATION; CROSS-SECTIONS; HELIUM-LIKE; BREIT; NEON AB A procedure for treating excitation of ions to specific magnetic sublevels by an electron beam is modified to apply for ionization. This is then used in the study of the linear polarization of the three x-ray lines (2p(5)3s)(1.)2 --> (2p(6))(0) emitted by Se24+. We do this by including population of the upper levels by innershell ionization of Na-like Se in addition to excitation from the (2p(6))(0) ground level of Ne-Iike Se both directly and via cascades from higher n = 3 levels. The required cross sections for both excitation and ionization to individual magnetic sublevels were computed in a fully relativistic distorted-wave method at impact energies ranging from 190 to 800 Ry. The radiative branching ratios were calculated using the fully relativistic GRASP atomic structure code. It is found that the innershell ionization process is almost unselective in populating the different \M \ sublevels of each upper level. Small values of the polarization degrees are obtained due to the combined effects of radiative cascades and inner-shell ionization. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ A Belkaid, Dept Phys, Tlemcen 13000, Algeria. RP Zhang, HL (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, POB 1663, Los Alamos, NM 87545 USA. NR 18 TC 2 Z9 2 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2001 VL 63 IS 5 BP art. no. EP 052713 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 430RJ UT WOS:000168589100070 ER PT J AU Baertschy, M Rescigno, TT McCurdy, CW Colgan, J Pindzola, MS AF Baertschy, M Rescigno, TT McCurdy, CW Colgan, J Pindzola, MS TI Ejected-energy differential cross sections for the near-threshold electron-impact ionization of hydrogen SO PHYSICAL REVIEW A LA English DT Article ID ATOMIC-HYDROGEN; SCATTERING; HELIUM; MODEL; BREAKUP; BEAM AB We have calculated, independently, the S-1 singly differential cross section for the electron-impact ionization of hydrogen at an incident energy of 4.0 eV above threshold using two different methods: time-dependent close coupling and exterior complex scaling, The absolute value of the S-1 cross section for equal energy sharing is critical in assessing recent theoretical and experimental results for coplanar triply differential cross sections at low energies. Convergence of the cross section is studied as a function of the number of coupled channels. We find that at this energy the singly differential cross section is relatively flat over the entire ejected-energy range as predicted by semiclassical calculations. C1 Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Phys Directorate, Livermore, CA 94551 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94551 USA. Auburn Univ, Dept Phys, Auburn, AL 36849 USA. RP Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. NR 27 TC 12 Z9 12 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2001 VL 63 IS 5 AR 050701 DI 10.1103/PhysRevA.63.050701 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 430RJ UT WOS:000168589100003 ER PT J AU Krstic, PS Reinhold, CO Burgdorfer, J AF Krstic, PS Reinhold, CO Burgdorfer, J TI Inelastic transitions in slow heavy-particle atomic collisions SO PHYSICAL REVIEW A LA English DT Article ID IONIZATION; EXCITATION; PROTONS; MODEL; STATE; IONS AB It is a generally held belief that inelastic transition probabilities and cross sections in slow, nearly adiabatic atomic collisions decrease exponentially with the inverse of the collision velocity v [i.e., sigma (alpha)exp(-const/v)]. This notion is supported by the Landau-Zener approximation and the hidden crossings approximation. We revisit the adiabatic limit of inn-atom collisions and show that for eely slow collisions radial transitions are dominated by the topology of the branch points of the radial velocity rather than the branch points of the energy eigensurface. This can lead to a dominant power-law dependence of inelastic cross sections, sigma alphav(n). We illustrate the interplay between different contributions to the transition probabilities in a one-dimensional collision system for which the exact probabilities can be obtained from a direct numerical solution of the time-dependent Schodinger equation. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Vienna Univ Technol, Inst Theoret Phys, A-1040 Vienna, Austria. RP Krstic, PS (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. OI Reinhold, Carlos/0000-0003-0100-4962 NR 37 TC 8 Z9 8 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2001 VL 63 IS 5 AR 052702 DI 10.1103/PhysRevA.63.052702 PG 16 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 430RJ UT WOS:000168589100059 ER PT J AU Abanov, A Chubukov, AV Schmalian, J AF Abanov, A Chubukov, AV Schmalian, J TI Singularities in the optical response of cuprates SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-SCATTERING; SPIN-FLUCTUATION; NORMAL-STATE; SUPERCONDUCTORS; BI2SR2CACU2O8+DELTA; CONDUCTIVITY; SPECTROSCOPY; TEMPERATURE; YBA2CU3O7; LEAD AB We argue that the detailed analysis of the optical response in cuprate superconductors allows one to verify the magnetic scenario of superconductivity in cuprates. As for strong coupling charge carriers to antiferromagnetic spin fluctuations, the second derivative of optical conductivity should contain detectable singularities at 2 Delta + Delta (spin), 4 Delta, and 2 Delta + 2 Delta (spin), where Delta is the amplitude of the superconducting gap, and Delta (s) is the resonance energy of spin fluctuations measured in neutron scattering. We argue that there is a good chance that these singularities have already been detected in the experiments on optimally doped Y-Ba-Cu-O. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Abanov, A (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. RI Schmalian, Joerg/H-2313-2011 NR 36 TC 34 Z9 34 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 18 AR 180510 DI 10.1103/PhysRevB.63.180510 PG 4 WC Physics, Condensed Matter SC Physics GA 432ZE UT WOS:000168730200021 ER PT J AU Aranson, IS Kopnin, NB Vinokur, VM AF Aranson, IS Kopnin, NB Vinokur, VM TI Dynamics of vortex nucleation by rapid thermal quench SO PHYSICAL REVIEW B LA English DT Article ID II SUPERCONDUCTORS; SYMMETRY-BREAKING; DEFECT FORMATION; SUPERFLUID; TRANSITION; VORTICES; HE-4 AB By numerical and analytical studies of the time-dependent Ginzburg-Landau model we show that vortex nucleation in superfluid He-3 by rapid thermal quench in the presence of superflow is dominated by a transverse instability of the moving normal-superfluid interface. The instability threshold is found analytically as a function of supercurrent density and the front velocity. The dynamics of vortex evolution at long times after the quench is investigated. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Helsinki Univ Technol, Low Temp Lab, FIN-02015 Helsinki, Finland. LD Landau Theoret Phys Inst, Moscow 117334, Russia. RP Aranson, IS (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Aranson, Igor/I-4060-2013 NR 30 TC 9 Z9 9 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 18 AR 184501 DI 10.1103/PhysRevB.63.184501 PG 12 WC Physics, Condensed Matter SC Physics GA 432ZE UT WOS:000168730200088 ER PT J AU Batista, CD Bonca, J Gubernatis, JE AF Batista, CD Bonca, J Gubernatis, JE TI Ferromagnetism in the two-dimensional periodic Anderson model SO PHYSICAL REVIEW B LA English DT Article ID KONDO-LATTICE MODEL; QUANTUM MONTE-CARLO; FERMION GROUND-STATES; HUBBARD-MODEL; PHASE-DIAGRAM; PAIRING CORRELATIONS; MEAN-FIELD; TRANSITION; ORDER AB Using the constrained-path Monte Carlo method, we studied the magnetic properties of the two-dimensional periodic Anderson model for electron fillings between 1/4 and 1/2. We also derived two effective low-energy theories to assist in interpreting the numerical results. For 1/4 filling, we found that the system can be a Mott or a charge-transfer insulator, depending on the relative values of the Coulomb interaction and the charge-transfer gap between the two noninteracting bands. The insulator may be a paramagnet or antiferromagnet. We concentrated on the effect of electron doping on these insulating phases. Upon doping we obtained a partially saturated ferromagnetic phase for low concentrations of conduction electrons, if the system were a charge-transfer insulator, we would find that the ferromagnetism is induced by the well-known Ruderman-Kittel-Kasuya-Yosida interaction. However, we found a novel correlated hopping mechanism inducing the ferromagnetism in the region where the nondoped system is a Mott insulator. Our regions of ferromagnetism spanned a much smaller doping range than suggested by recent slave boson and dynamical mean-field theory calculations, but they were consistent with that obtained by density-matrix renormalization group calculations of the one-dimensional periodic Anderson model. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Ljubljana, FMF, Dept Phys, Ljubljana, Slovenia. Jozef Stefan Inst, Ljubljana, Slovenia. RP Batista, CD (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RI Batista, Cristian/J-8008-2016 NR 40 TC 6 Z9 6 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 18 AR 184428 DI 10.1103/PhysRevB.63.184428 PG 13 WC Physics, Condensed Matter SC Physics GA 432ZE UT WOS:000168730200077 ER PT J AU Chmaissem, O Eckstein, Y Kuper, CG AF Chmaissem, O Eckstein, Y Kuper, CG TI Structure and a bond-valence-sum study of the 1-2-3 superconductors (CaxLa1-x)(Ba1.75La0.25+x)Cu3Oy and YBa2Cu3Oy SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTING TRANSITION-TEMPERATURE; RAY-ABSORPTION-SPECTROSCOPY; CRYSTAL-STRUCTURE; CUPRATE SUPERCONDUCTORS; OXYGEN; BA2YCU3OX; SYSTEM; PHASE; TC AB We present a study of the crystal structure of the 1-2-3 superconductor (CaxLa1-x) (Ba1.75-xLa0.25+x)Cu3Oy (CLBLCO). Because of the presence of bath La and Ba ions in the "Ba" layer, the local symmetry of YBa2Cu3Oy (YBCO) is lost. For example, one can no longer assume that an "apical" oxygen atom always lies strictly on the line joining Cu I and Cu II ions, and a Pauling bond-valence calculation is very useful as an adjunct to the Rietveld refinement of the positions of the La and Ba ions. When a Rietveld analysis is performed allowing for the possibility that the apical oxygen atoms may be slightly displaced along the a or b direction, the bond-valence sums for both La and Ba are close to the natural oxidation states of these ions. We have also used the bend-valence-sum method to study the mean oxidation states of the Cu I and Cu II ions in both CLBLCO and YBCO. Our results for YBCO differ from some previously published results. Our main conclusion is that, while the method may be useful in finding the charge concentration on the Cu II plane, it definitely does not yield the concentration of mobile holes, nor the concentration of superconducting charge carriers. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. Technion Israel Inst Technol, Crown Ctr Superconduct, IL-32000 Haifa, Israel. RP Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 28 TC 24 Z9 24 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 174510 DI 10.1103/PhysRevB.63.174510 PG 10 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300101 ER PT J AU Chubukov, AV Janko, B Tchernyshyov, O AF Chubukov, AV Janko, B Tchernyshyov, O TI Dispersion of the neutron resonance in cuprate superconductors SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; T-C; MAGNETIC EXCITATIONS; SCATTERING; SPIN; YBA2CU3O7; STATE; BI2SR2CACU2O8+DELTA; ANTIFERROMAGNETS; DYNAMICS AB We argue that recently measured downward dispersion of the neutron resonance peak in cuprate superconductors is naturally explained if the resonance is viewed as a spin-1 collective mode in a d-wave superconductor. The reduction of the resonant frequency away from the antiferromagnetic wave vector is a direct consequence of the momentum dependence of the d-wave superconducting gap. When the magnetic correlation length becomes large, the dispersion should become magnonlike. i.e.. curve upwards from (pi,pi). C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Inst Adv Study, Sch Nat Sci, Princeton, NJ 08540 USA. RP Chubukov, AV (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 37 TC 36 Z9 36 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 18 AR 180507 DI 10.1103/PhysRevB.63.180507 PG 4 WC Physics, Condensed Matter SC Physics GA 432ZE UT WOS:000168730200018 ER PT J AU Collins, LA Bickham, SR Kress, JD Mazevet, S Lenosky, TJ Troullier, NJ Windl, W AF Collins, LA Bickham, SR Kress, JD Mazevet, S Lenosky, TJ Troullier, NJ Windl, W TI Dynamical and optical properties of warm dense hydrogen SO PHYSICAL REVIEW B LA English DT Article ID EQUATION-OF-STATE; COMPRESSED LIQUID DEUTERIUM; INITIO MOLECULAR-DYNAMICS; INSULATOR-METAL TRANSITION; TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; ELECTRICAL-CONDUCTIVITY; FLUID HYDROGEN; SIMULATIONS; DISSOCIATION AB We report dynamical and optical properties of hydrogen (deuterium) around the region of the principal Hugoniot that starts from the cryogenically cooled molecular liquid. These properties were determined by finite-temperature density functional (FTDF) molecular dynamics (MD) simulations within the local density and generalized gradient approximations. The principal Hugoniot, calculated from the FTDF-MD equation of stare, agrees with gas-gun and recent laser-shock experiments for pressures up to 50 GPa. However, the maximum compression of the FTDF-MD Hugoniot (4.6 at 52 GPa) significantly differs from that of the laser shock experiment (6 at about 150 GPa). On the other hand, the optical reflectivities show reasonable agreement with the laser measurements for pressures up to 70 GPa. The system smoothly dissociates along the Hugoniot with the electrical conductivity reaching a value of 4000 Ohm (-1) cm(-1) at maximum compression. We also obtain good agreement with previous tight-binding and ab initio molecular dynamics studies. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Minnesota, Minneapolis, MN 55455 USA. Motorola Inc, Computat Mat, Austin, TX 78721 USA. RP Collins, LA (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Windl, Wolfgang/C-7255-2012 OI Windl, Wolfgang/0000-0001-5892-0684 NR 68 TC 108 Z9 111 U1 0 U2 12 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 18 AR 184110 DI 10.1103/PhysRevB.63.184110 PG 11 WC Physics, Condensed Matter SC Physics GA 432ZE UT WOS:000168730200032 ER PT J AU Deac, IG Mitchell, JF Schiffer, P AF Deac, IG Mitchell, JF Schiffer, P TI Phase separation and low-field bulk magnetic properties of Pr0.7Ca0.3MnO3 SO PHYSICAL REVIEW B LA English DT Article ID METAL TRANSITION; SPIN-GLASS; PR1-XCAXMNO3; MANGANITES; BEHAVIOR; MAGNETORESISTANCE; TEMPERATURE; PEROVSKITES; STATE AB We present a detailed magnetic study of the perovskite manganite Pr0.7Ca0.3MnO3 at low temperatures including magnetization and ac susceptibility measurements. The data appear to exclude a conventional spin glass phase at low fields, suggesting instead the presence of correlated ferromagnetic clusters embedded in a charge-ordered matrix. We examine the growth of the ferromagnetic clusters with increasing magnetic field as they expand to occupy almost the entire sample at H similar to0.5 T. Since this is well below the field required to induce a metallic state, our results point to the existence of a field-induced ferromagnetic insulating state in this material. C1 Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Univ Babes Bolyai, Dept Phys, R-3400 Cluj Napoca, Romania. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Penn State Univ, Mat Res Inst, University Pk, PA 16802 USA. RP Deac, IG (reprint author), Penn State Univ, Dept Phys, University Pk, PA 16802 USA. EM schiffer@phys.psu.edu RI Schiffer, Peter/F-3227-2011 NR 39 TC 123 Z9 124 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 172408 DI 10.1103/PhysRevB.63.172408 PG 5 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300017 ER PT J AU Espinosa, FJ Villella, P Lashley, JC Conradson, SD Cox, LE Martinez, R Martinez, B Morales, L Terry, J Pereyra, RA AF Espinosa, FJ Villella, P Lashley, JC Conradson, SD Cox, LE Martinez, R Martinez, B Morales, L Terry, J Pereyra, RA TI Local atomic structure of alpha-Pu SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION FINE-STRUCTURE; LIGHT ACTINIDES; CRYSTAL-STRUCTURE; PLUTONIUM AB The local atomic structure of alpha -Pu was investigated using x-ray absorption tine structure (XAFS) spectroscopy. XAFS spectra were obtained for a zone-refined alpha -Pu and the results were compared to 32-year-old and Ce-doped (0.34 at. %) samples. X-ray diffraction (XRD) patterns were also measured for the zone-refined and 32-year-old materials. The extent of the Bragg peaks showed that amorphization of the 32-year-old sample had nor occurred despite the prolonged exposure to self-radiation. Analogous to metastable delta -Pu alloys, the local atomic structure around Pu for the zone-refined material shows the possible presence of noncrystallographic Pu-Pu distances. Conversely, the Ce and the 32-year-old sample show no evidence for such noncrystallographic distances. Disorder in the Pu local environment was found to be impurity dependent. The Ce-doped sample presented a larger Pu-Pu nearest neighbor disorder than the aged sample, although the total amount of Am. U. and He impurities was actually higher in the aged sample. The local environment around U and Ce impurities is consistent with these elements being in substitutional lattice sites. In addition. U and Ce do not introduce significant lattice distortion to their nearest neighbors. This is consistent with disorder being more related to the perturbation of the coupling between the electronic and crystal structure, or the Peierls-Jahn-Teller distortion that generates the monoclinic alpha -Pu structure, and less to strain fields produced in the vicinity of the impurities. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 20 TC 16 Z9 16 U1 2 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 174111 DI 10.1103/PhysRevB.63.174111 PG 8 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300047 ER PT J AU Holicki, M Fehske, H Werner, R AF Holicki, M Fehske, H Werner, R TI Magnetoelastic excitations in spin-Peierls systems SO PHYSICAL REVIEW B LA English DT Article ID MATRIX-RENORMALIZATION-GROUP; MICROSCOPIC COUPLINGS; LATTICE FLUCTUATIONS; CUGEO3; TRANSITION; CHAINS; PHASE; DIMERIZATION; TEMPERATURE; DYNAMICS AB From the random-phase approximation to the spin-Peierls transition, two parameter regimes of phonon softening and hardening are present. Magnetoelastic excitations are discussed in detail for phonons coupled to the exactly solvable model of XY spin chains for both regimes, leading to a modified interpretation of the 30-cm(-1) mode in CuGeO3. Frustrated Heisenbeg chains coupled to phonons satisfactorily describe the pretransitional quasielastic scattering in CuGeO3. A real-space interpretation of the quasielastic scattering is given justifying effective Ising-model approaches. C1 Univ Bayreuth, Dept Phys, D-95440 Bayreuth, Germany. Berg Univ Gesamthsch Wuppertal, Dept Phys, D-42097 Wuppertal, Germany. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Holicki, M (reprint author), Univ Leipzig, Math Inst, D-04109 Leipzig, Germany. NR 52 TC 9 Z9 9 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 174417 DI 10.1103/PhysRevB.63.174417 PG 12 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300067 ER PT J AU Koyama, T Matsumoto, M Wada, S Sarrao, JL AF Koyama, T Matsumoto, M Wada, S Sarrao, JL TI Yb-171 and Cu-63 magnetic resonance studies on the fluctuating valent compound YbInCu4 SO PHYSICAL REVIEW B LA English DT Article ID PHASE-TRANSITION; YBXIN1-XCU2; PRESSURE; FIELD; YBIN1-XAGXCU4; BEHAVIOR; NQR; NMR AB We report a nuclear magnetic resonance (NMR) investigation on the fluctuating valent compound YbInCu4, which exhibits the first-order isostructural valence transition at T-V = 45-50 K. Yb-171 NMR was observed in the range between 1.9-4.2 K in the low-temperature (LT) phase with the Knight shift of 101.3%. The hyperfine coupling constant of 0.88 x 10(6) Oe/mu (B) is about 24% smaller than the value expected for the J = 7/2 state of free Yb3+ ions. The strongly enhanced paramagnetic behavior with large Korringa-like relaxation rate, (T1T)(-1) similar or equal to 1.1 X 10(4) (s K)(-1), is consistent with the formation of s-f resonance bands. Cu-63 Knight shift K(Cu-63) shows a Curie-Weiss-type behavior in high-temperature (HT) phase, and a temperature-independent behavior in the LT phase. It is found that K(Cu-63) vs nu(Cu-63) (electric-quadrupole frequency) plots in the HT phase are on a straight line for the most part. and deviate slightly from the line as the temperature approaches T-V. In the LT phase, on the other hand, the plots exhibit a small deviation from the line in the opposite direction. As the increase in nu(Cu-63) for YbInCu4 is caused by the decrease in the cell volume, it is concluded that the Kondo volume collapse (expansion) model may describe the physics of YbInCu4 associated with the valence fluctuations. The deviation from the line is thought to be due to the variation of the coupling J(af) between the conduction electron density and Yb's 4f electrons. C1 Kobe Univ, Grad Sch Sci & Technol, Dept Mat Sci, Nada Ku, Kobe, Hyogo 6578501, Japan. Kobe Univ, Fac Sci, Dept Phys, Nada Ku, Kobe, Hyogo 6578501, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Koyama, T (reprint author), Kobe Univ, Grad Sch Sci & Technol, Dept Mat Sci, Nada Ku, Kobe, Hyogo 6578501, Japan. NR 31 TC 7 Z9 7 U1 1 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 172410 DI 10.1103/PhysRevB.63.172410 PG 4 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300019 ER PT J AU Levin, EM Pecharsky, VK Gschneidner, KA AF Levin, EM Pecharsky, VK Gschneidner, KA TI Spontaneous generation of voltage in Gd-5(SixGe4-x) during a first-order phase transition induced by temperature or magnetic SO PHYSICAL REVIEW B LA English DT Article ID ELECTRICAL-RESISTANCE; GD-5(SI2GE2); ALLOYS; FIELD; MAGNETORESISTANCE; THERMOELECTRICITY; GD-5(SI1.8GE2.2); TRANSFORMATION AB The spontaneous generation of voltage has been observed during the first-order magnetic-Martensitic phase transition process in Gd-5(SixGe4-x) alloys regardless of whether the transformation is triggered by temperature or magnetic field. Based on various experimental data we show that thermoelectric power is a major contributor to the observed voltage. The characteristics of the simultaneously recorded spontaneous voltage and the signal from a differential thermocouple attached to the sample are quite complex, indicating that thermal effects arising in this class of materials during the first-order phase transition ore nontrivial. The unusual dynamics of both the heat release and absorption during the phase transformations in Gd-5(SixGe4-x) result in the appearance of temperature gradients and, therefore, thermoelectricity. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 23 TC 47 Z9 48 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 174110 DI 10.1103/PhysRevB.63.174110 PG 7 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300046 ER PT J AU Lilly, MP Hallock, RB AF Lilly, MP Hallock, RB TI Probing the internal structure of nuclepore with hysteretic capillary condensation SO PHYSICAL REVIEW B LA English DT Article ID LIQUID-HELIUM FILMS; THIRD SOUND; HE-4; ADSORPTION; MODELS; PORES; THERMODYNAMICS; PERCOLATION; DESORPTION; AVALANCHES AB We report filling (adsorption) and draining (desorption) measurements of superfluid He-4 in the porous material nuclepore. These low-temperature measurements explore the classical hysteretic properties of the capillary condensation of the liquid, while utilizing the propagation of third sound in the superfluid helium as an in situ probe of the chemical potential. We present measurements of global hysteresis loops, subloops, and reversal curves. With this data, we determine that the interconnected pore structure of the material is critical to the draining process. In addition, we present measurements of the connectivity and pore size distributions for nuclepore, and compare these results to calculations and earlier measurements. This work establishes the utility of the novel working fluid superfluid He-4 and the applicability of the techniques used here for such studies of porous materials. C1 Univ Massachusetts, Dept Phys, Low Temp Phys Lab, Amherst, MA 01003 USA. RP Lilly, MP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM hallock@physics.umass.edu NR 37 TC 9 Z9 9 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 174503 DI 10.1103/PhysRevB.63.174503 PG 17 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300094 ER PT J AU Moreno, NO Pagliuso, PG Rettori, C Gardner, JS Sarrao, JL Thompson, JD Huber, D Mitchell, JF Martinez, JJ Oseroff, SB AF Moreno, NO Pagliuso, PG Rettori, C Gardner, JS Sarrao, JL Thompson, JD Huber, D Mitchell, JF Martinez, JJ Oseroff, SB TI Electron spin resonance above T-C in layered manganites SO PHYSICAL REVIEW B LA English DT Article ID SHORT-RANGE ORDER; GIANT MAGNETORESISTANCE; PARAMAGNETIC-RESONANCE; MAGNETIC-RESONANCE; LASR2MN2O7; DYNAMICS; EPR; LA1.2SR1.8MN2O7; PEROVSKITES; ESR AB We have performed electron spin resonance (ESR) and de magnetization measurements on single crystals of La2(1-x)Sr1+2xMn2O7 up to 800 K with special emphasis on the x=0.4 composition. The ESR linewidth shows behavior similar to that observed in the three-dimensional perovskites and above similar to 500 K can be described by a universal expression DeltaH(pp)(T)=[C/T chi (T)]DeltaH(pp)(infinity). The linewidth and the resonance field become anisotropic below similar to 500 K. The anisotropy in the resonance field is proportional to the magnetization M, and we concluded that it is intrinsic to the system. We show that demagnetization effects can explain only part of the anisotropy. The remainder arises from short-range uniaxial terms in the Hamiltonian that are associated with the crystal field and Dzialozhinsky-Moriya interactions. The anisotropy in the linewidth is attributed to the easy-plane ferromagnetic ordering, which also arises from the short-range anisotropy. C1 UNICAMP, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Wisconsin, Madison, WI 53706 USA. Argonne Natl Lab, Argonne, IL 60439 USA. San Diego State Univ, San Diego, CA 92182 USA. RP Moreno, NO (reprint author), UNICAMP, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. RI Rettori, Carlos/C-3966-2012; Pagliuso, Pascoal/C-9169-2012; Moreno, Nelson/H-1708-2012; Gardner, Jason/A-1532-2013; Inst. of Physics, Gleb Wataghin/A-9780-2017 OI Rettori, Carlos/0000-0001-6692-7915; Moreno, Nelson/0000-0002-1672-4340; NR 33 TC 25 Z9 25 U1 1 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 174413 DI 10.1103/PhysRevB.63.174413 PG 6 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300063 ER PT J AU Radaelli, PG Ibberson, RM Argyriou, DN Casalta, H Andersen, KH Cheong, SW Mitchell, JF AF Radaelli, PG Ibberson, RM Argyriou, DN Casalta, H Andersen, KH Cheong, SW Mitchell, JF TI Mesoscopic and microscopic phase segregation in manganese perovskites SO PHYSICAL REVIEW B LA English DT Article ID COLOSSAL MAGNETORESISTANCE; PR1-XCAXMNO3; TRANSITION; SEPARATION; MANGANITES; CHARGE; PR0.7CA0.3MNO3; LA1-XCAXMNO3; PHYSICS; X=0.25 AB Mesoscopic (500-2000 Angstrom) and microscopic (5-20 Angstrom) phase segregation with temperature and magnetic field was studied in the model manganite Pr0.7Ca0.3MnO3 by high-resolution neutron diffraction and inelastic neutron scattering. Intragranular strain-driven mesoscopic segregation between two insulating phases, one of which is charge ordered (CO), sets in below the CO temperature in zero field. The CO phase orders antiferromagnetically, while the other insulating phase shows spin-glass behavior. After field-induced metallization, the CO phase coexists with a ferromagnetic metallic phase. C1 Rutherford Appleton Lab, CCLRC, ISIS Facil, Didcot OX11 0QX, Oxon, England. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08855 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. RI Radaelli, Paolo/C-2952-2011; Ibberson, Richard/P-8397-2015 OI Radaelli, Paolo/0000-0002-6717-035X; Ibberson, Richard/0000-0003-0007-706X NR 25 TC 122 Z9 123 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 172419 DI 10.1103/PhysRevB.63.172419 PG 4 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300028 ER PT J AU Samara, GA Venturini, EL Schmidt, VH AF Samara, GA Venturini, EL Schmidt, VH TI Dielectric properties and phase transitions of [Pb(Zn1/3Nb2/3)O-3](0.905)(PbTiO3)(0.095): Influence of pressure SO PHYSICAL REVIEW B LA English DT Article ID SOFT MODE FERROELECTRICS; CURIE-WEISS BEHAVIOR; SHORT-RANGE ORDER; RELAXOR FERROELECTRICS; SINGLE-CRYSTALS; INDUCED CROSSOVER; GLASSY PROPERTIES; SPIN-GLASS; PROBE AB Studies of the influences of temperature, hydrostatic pressure, de biasing field, and frequency on the dielectric constant (epsilon') and loss (tan delta) of single crystal [Pb(Zn1/3Nb2/3)O-3](0.905)(PbTiO3)(0.095), or PZN-9.5 PT for short, have provided a detailed view of the ferroelectric (FE) response and phase transitions of this technologically important material. While at 1 bar, the crystal exhibits on cooling a cubic-to-tetragonal FE transition followed by a second transition to a rhombohedral phase, pressure induces a FE-to-relaxor crossover, the relaxer phase becoming the ground state at pressures greater than or equal to5 kbar. Analogy with earlier results suggests that this crossover is a common feature of compositionally disordered soft mode ferroelectrics and can be understood in terms of a decrease in the correlation length among polar domains with increasing pressure. Application of a de biasing electric field at 1 bar strengthens FE correlations, and can at high pressure restabilize the FE response. The temperature-pressure and temperature-electric field phase diagrams were established. In the absence of dc bias the tetragonal phase vanishes at high pressure, the crystal exhibiting classic relaxor behavior. The dynamics of dipolar motion and the strong deviation from Curie-Weiss behavior of the susceptibility in the high-temperature cubic phase are discussed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. RP Samara, GA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 24 TC 47 Z9 50 U1 2 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 18 AR 184104 DI 10.1103/PhysRevB.63.184104 PG 11 WC Physics, Condensed Matter SC Physics GA 432ZE UT WOS:000168730200026 ER PT J AU Trepakov, VA Savinov, ME Giulotto, E Galinetto, P Camagni, P Samoggia, G Boatner, LA Kapphan, SE AF Trepakov, VA Savinov, ME Giulotto, E Galinetto, P Camagni, P Samoggia, G Boatner, LA Kapphan, SE TI Dipole ordering effects and reentrant dipolar glass state in KTaO3 : Li,Nb SO PHYSICAL REVIEW B LA English DT Article ID FERROELECTRIC PHASE-TRANSITION; SITE ELECTRIC-DIPOLE; RAMAN-SCATTERING; DISORDERED FERROELECTRICS; KTAO3; IMPURITY; LI AB Dielectric permittivity and Raman-scattering studies reveal unconventional dipole ordering and structural effects that arise in the incipient ferroelectric KTaO3 due to the simultaneous presence of off-center Li+ and Nb5+ ions. A soft-mode-driven transition into a ferroelectric phase accompanied by the formation of a dipole glass in the Li+ subsystem was identified at 39 K in a sample of composition K0.9986Li0.0014Ta0.988Nb0.012O3. A second soft-mode transition was found at 30 K. whereas a transition into a phase identified as a "reentrant dipolar glasslike state" was observed at 15 K. Such a sequence of phases, diordered-long range ordered-reentrant glass, already known for disordered ferromagnets. is here reported for a highly polarizable matrix with soft modes. C1 Acad Sci Czech Republ, Inst Phys, Prague 18221 8, Czech Republic. Univ Pavia, Dipartimento Fis A Volta, I-27100 Pavia, Italy. INFM, I-27100 Pavia, Italy. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Osnabruck, Fachbereich Phys, D-49069 Osnabruck, Germany. AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. RP Trepakov, VA (reprint author), Acad Sci Czech Republ, Inst Phys, Na Slovance 2, Prague 18221 8, Czech Republic. EM vlad@trevl.ioffe.rssi.ru RI Trepakov, Vladimir/H-1352-2014; Savinov, Maxim/H-2417-2014 NR 29 TC 11 Z9 11 U1 3 U2 14 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 172203 DI 10.1103/PhysRevB.63.172203 PG 4 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300006 ER PT J AU Wakimoto, S Birgeneau, RJ Lee, YS Shirane, G AF Wakimoto, S Birgeneau, RJ Lee, YS Shirane, G TI Hole concentration dependence of the magnetic moment in superconducting and insulating La2-xSrxCuO4 SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-SCATTERING; DOPED LA2-XSR(X)CUO4; SPIN CORRELATIONS; PHASE-DIAGRAM; ORDER; STATE; ANTIFERROMAGNETISM; LA1.88SR0.12CUO4; LA2-XBAXCUO4; FLUCTUATIONS AB Recent neutron-scattering measurements on the La2-xSrxCuO4 system have revealed a drastic change of the incommensurate static-spin correlations from diagonal in the insulating region to parallel in the superconducting region. We report the eloping dependence of the ordered magnetic moment for the hole concentration region 0.03 less than or equal to x less than or equal to 0.12, focusing on the relationship between the static magnetism and the superconductivity. The elastic magnetic cross-section decreases monotonically with increasing x for 0.03 less than or equal to x less than or equal to 0.07. We find that the ordered magnetic moment mu varies from similar to 0.18 mu (B)/Cu(x = 0.03) to similar to 0.06 mu (B)/Cu(x = 0.07). No significant anomaly is observed at the: insulator-superconductor boundary (x similar to 0.055). The elastic magnetic cross-section is enhanced in the vicinity of x = 0.12 where resolution-limited width peaks are observed in neutron-scattering measurements and where the apparent magnetic and superconducting transitions coincide. C1 MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. NCNR, Natl Inst Stand & Technol, Bethesda, MD 20889 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Univ Toronto, Dept Phys, 60 St George St, Toronto, ON M5S 1A7, Canada. NR 29 TC 44 Z9 44 U1 1 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 MAY 1 PY 2001 VL 63 IS 17 AR 172501 DI 10.1103/PhysRevB.63.172501 PG 4 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300030 ER PT J AU Weinstein, M AF Weinstein, M TI Contractor renormalization group and the Haldane conjecture SO PHYSICAL REVIEW B LA English DT Article ID FIELD-THEORIES; SPIN CHAINS; LATTICE; ANTIFERROMAGNETS; MODEL; STATE AB The contractor renormalization group formalism (CORE) is a real-space renormalization group method which is the Hamiltonian analogue of the Wilson exact renormalization group equations. In an earlier paper [Phys. Rev. D 61, 034505 (2000)] I showed that the CORE method could be used to map a theory of free quarks and quarks interacting with gluons into a generalized frustrated Heisenberg antiferromagnet (HAF) and proposed using CORE methods to study these theories. Since generalizations of HAF's exhibit all sorts of subtle behavior which, from a continuum point of view, are related to topological properties of the theory, it is important to know that CORE can be used to extract this physics. In this paper I show that despite the folklore which asserts that all real-space renormalization group schemes are necessarily inaccurate, simple CORE computations can give highly accurate results even if one only keeps a small number of states per block and a few terms in the cluster expansion. In addition I argue that even very simple CORE computations give a much better qualitative understanding of the physics than naive renormalization group methods. In particular I show that the simplest CORE computation yields a first-principles understanding of how the famous Haldane conjecture works for the case of the spin-1/2 and spin-1 HAF. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Weinstein, M (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 22 TC 19 Z9 19 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 174421 DI 10.1103/PhysRevB.63.174421 PG 16 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300071 ER PT J AU Werner, R AF Werner, R TI Dynamical dimer-dimer correlation functions from exact diagonalization SO PHYSICAL REVIEW B LA English DT Article ID SPIN-PEIERLS TRANSITION; MATRIX-RENORMALIZATION-GROUP; MAGNETIC-FIELD; CUGEO3; CHAIN; FLUCTUATIONS; TEMPERATURE; COUPLINGS; NEIGHBOR; SYSTEMS AB A regularization method is presented to deduce dynamic correlation functions from exact diagonalization calculations. It is applied to dimer-dimer correlation functions in quantum spin chains relevant for the description of spin-Peierls systems. Exact results for the XY model are presented. The analysis draws into doubt that the dimer-dimer correlation functions show the same scale invariance as spin-spin correlation functions. The results are applied to describe the quasielastic scattering in CuGeO3 and the hardening of the Peierls-active phonons. C1 Berg Univ Wuppertal, Dept Phys, D-42097 Wuppertal, Germany. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Berg Univ Wuppertal, Dept Phys, Fachbereich 9, D-42097 Wuppertal, Germany. NR 31 TC 2 Z9 2 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2001 VL 63 IS 17 AR 174416 DI 10.1103/PhysRevB.63.174416 PG 9 WC Physics, Condensed Matter SC Physics GA 428XQ UT WOS:000168487300066 ER PT J AU Armstrong, TA Barish, KN Batsouli, S Bennett, SJ Bertaina, M Chikanian, A Coe, SD Cormier, TM Davies, RR DeCataldo, G Dee, P Diebold, GE Dover, CB Fachini, P Fadem, B Finch, LE George, NK Giglietto, N Greene, SV Haridas, P Hill, JC Hirsch, AS Hoversten, RA Huang, HZ Jaradat, H Kim, B Kumar, BS Lainis, T Lajoie, JG Lewis, RA Li, Q Libby, B Majka, RD Miller, TE Munhoz, MG Nagle, JL Pless, IA Pope, JK Porile, NT Pruneau, CA Rabin, MSZ Reid, JD Rimai, A Rose, A Rotondo, FS Sandweiss, J Scharenberg, RP Slaughter, AJ Smith, GA Spinelli, P Tincknell, ML Toothacker, WS Van Buren, G Wilson, WK Wohn, FK Wolin, EJ Xu, Z Zhao, K AF Armstrong, TA Barish, KN Batsouli, S Bennett, SJ Bertaina, M Chikanian, A Coe, SD Cormier, TM Davies, RR DeCataldo, G Dee, P Diebold, GE Dover, CB Fachini, P Fadem, B Finch, LE George, NK Giglietto, N Greene, SV Haridas, P Hill, JC Hirsch, AS Hoversten, RA Huang, HZ Jaradat, H Kim, B Kumar, BS Lainis, T Lajoie, JG Lewis, RA Li, Q Libby, B Majka, RD Miller, TE Munhoz, MG Nagle, JL Pless, IA Pope, JK Porile, NT Pruneau, CA Rabin, MSZ Reid, JD Rimai, A Rose, A Rotondo, FS Sandweiss, J Scharenberg, RP Slaughter, AJ Smith, GA Spinelli, P Tincknell, ML Toothacker, WS Van Buren, G Wilson, WK Wohn, FK Wolin, EJ Xu, Z Zhao, K CA E864 Collaboration TI Search for strange quark matter produced in relativistic heavy ion collisions SO PHYSICAL REVIEW C LA English DT Article ID SCINTILLATING-FIBER CALORIMETER; NUCLEUS-NUCLEUS COLLISIONS; BOUND-STATES; HADRONIC MATTER; NEGATIVE PIONS; H-DIBARYON; GLUON PLASMA; WEAK DECAY; GEV/C SI; NEUTRONS AB We present the final results from Experiment 864 of a search for charged and neutral strange quark matter produced in interactions of 11.5 GeV/c per nucleon Au beams with Pt or Pb targets. Searches were made for strange quark matter with A greater than or equal to 5. Approximately 3 X 10(10) 10% most central collisions were sampled and no strangelet states with A less than or equal to 100 were observed. We find 90% confidence level upper limits of approximately 10(-8) per central collision for both charged and neutral strangelets. These limits are for strangelets with proper lifetimes greater than 50 ns. Also limits for H-0-d and pineut production are given. The above limits are compared with the predictions of various models. The yields of light nuclei from coalescence are measured and a penalty factor for the addition of one nucleon to the coalescing nucleus is determined. This is useful in gauging the significance of our upper limits and also in planning future searches for strange quark matter. C1 Penn State Univ, University Pk, PA 16802 USA. Univ Bari, Ist Nazl Fis Nucl, Bari, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Columbia Univ, New York, NY 10027 USA. Iowa State Univ, Ames, IA 50011 USA. Univ Massachusetts, Amherst, MA 01003 USA. MIT, Cambridge, MA 02139 USA. Purdue Univ, W Lafayette, IN 47907 USA. US Mil Acad, West Point, NY 10996 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Wayne State Univ, Detroit, MI 48201 USA. Yale Univ, New Haven, CT 06520 USA. RP Penn State Univ, University Pk, PA 16802 USA. RI giglietto, nicola/I-8951-2012; OI giglietto, nicola/0000-0002-9021-2888; Bertaina, Mario Edoardo/0000-0003-1069-1397 NR 73 TC 24 Z9 26 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2001 VL 63 IS 5 AR 054903 DI 10.1103/PhysRevC.63.054903 PG 18 WC Physics, Nuclear SC Physics GA 431PZ UT WOS:000168640900038 ER PT J AU Brome, CR Butterworth, JS Dzhosyuk, SN Mattoni, CEH McKinsey, DN Doyle, JM Huffman, PR Dewey, MS Wietfeldt, FE Golub, R Habicht, K Greene, GL Lamoreaux, SK Coakley, KJ AF Brome, CR Butterworth, JS Dzhosyuk, SN Mattoni, CEH McKinsey, DN Doyle, JM Huffman, PR Dewey, MS Wietfeldt, FE Golub, R Habicht, K Greene, GL Lamoreaux, SK Coakley, KJ TI Magnetic trapping of ultracold neutrons SO PHYSICAL REVIEW C LA English DT Article ID COLD NEUTRONS; LIQUID-HELIUM; SUPERFLUID-HELIUM; STORAGE RING; LIFETIME; HE-4; SCATTERING; LIGHT; DECAY; UCN AB Three-dimensional magnetic confinement of neutrons is reported. Neutrons are loaded into an Ioffe-type superconducting magnetic trap through inelastic scattering of cold neutrons with He-4. Scattered neutrons with sufficiently low energy and in the appropriate spin state are confined by the magnetic field until they decay. The electron resulting from neutron decay produces scintillations in the liquid helium bath that results in a pulse of extreme ultraviolet light. This light is frequency downconverted to the visible and detected. Results are presented in which 500+/-155 neutrons are magnetically trapped in each loading cycle, consistent with theoretical predictions. The lifetime of the observed signal, 660(-170)(+290) s, is consistent with the neutron beta-decay lifetime. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Harvard Univ, Cambridge, MA 02138 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Brome, CR (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,MS 8461, Gaithersburg, MD 20899 USA. RI Habicht, Klaus/K-3636-2013; OI Habicht, Klaus/0000-0002-9915-7221; Huffman, Paul/0000-0002-2562-1378 NR 47 TC 20 Z9 20 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2001 VL 63 IS 5 AR 055502 DI 10.1103/PhysRevC.63.055502 PG 15 WC Physics, Nuclear SC Physics GA 431PZ UT WOS:000168640900047 ER PT J AU Gueye, P Bernheim, M Danel, JF Ducret, JE Lakehal-Ayat, L Le Goff, JM Magnon, A Marchand, C Morgenstern, J Marroncle, J Vernin, P Zghiche-Lakehal-Ayat, A Breton, V Frullani, S Garibaldi, F Ghio, F Jodice, M Meziani, ZE Offermann, E Traini, M AF Gueye, P Bernheim, M Danel, JF Ducret, JE Lakehal-Ayat, L Le Goff, JM Magnon, A Marchand, C Morgenstern, J Marroncle, J Vernin, P Zghiche-Lakehal-Ayat, A Breton, V Frullani, S Garibaldi, F Ghio, F Jodice, M Meziani, ZE Offermann, E Traini, M TI Corrections to the one-photon approximation in the 0(+)-> 2(+) transition of C-12 SO PHYSICAL REVIEW C LA English DT Article ID ELASTIC ELECTRON-SCATTERING; POSITRON SCATTERING; ENERGY-DEPENDENCE AB Contribution of higher order effects to the one-photon exchange approximation were studied in the first excited state of C-12 by comparing inclusive inelastic scattering cross sections of electrons and positrons obtained at the Saclay Linear Accelerator. The data were compared lo a distorted wave Born approximation (DWBA) calculation. The results indicate an effect less than 2% within 2 sigma, compatible with what was observed in recent elastic scattering measurements. C1 CEA Saclay, Serv Phys Nucl, DAPNIA, F-91191 Gif Sur Yvette, France. Univ Blaise Pascal, Inst Phys Nucl & Phys Particules, Phys Corpusculaire Lab, F-63177 Clermont Ferrand, France. Ist Super Sanita, Fis Lab, I-00161 Rome, Italy. Ist Fis Nucl, Sez Sanit, I-00161 Rome, Italy. Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Univ Trent, Dipartimento Fis, I-38050 Trent, Italy. Ist Nazl Fis Nucl, I-38050 Trent, Italy. RP Gueye, P (reprint author), CEA Saclay, Serv Phys Nucl, DAPNIA, F-91191 Gif Sur Yvette, France. RI Le Goff, Jean-Marc/E-7629-2013; GHIO, FRANCESCO/F-2092-2015 NR 19 TC 0 Z9 0 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2001 VL 63 IS 5 AR 051303 PG 3 WC Physics, Nuclear SC Physics GA 431PZ UT WOS:000168640900004 ER PT J AU Nollett, KM AF Nollett, KM TI Radiative alpha-capture cross sections from realistic nucleon-nucleon interactions and variational Monte Carlo wave functions SO PHYSICAL REVIEW C LA English DT Article ID ASTROPHYSICAL-S-FACTOR; CLUSTER MODEL; LOW ENERGIES; RESONATING-GROUP; H-3(ALPHA,GAMMA)LI-7 REACTION; GAMMA)LI-7 REACTIONS; ZERO ENERGY; A=7 NUCLEI; HE-3(ALPHA,GAMMA)BE-7; LI-7 AB We report the first calculations of cross sections for the radiative capture reactions H-3(alpha,gamma)Li-7 and He-3(alpha, gamma)Be-7 below 2 MeV that use wave functions derived from realistic nucleon-nucleon interactions by the variational Monte Carte technique. After examining several small corrections to the dominant E1 operator, we find energy dependences for the low-energy S factors that agree reasonably with experimental measurements. There is no contradiction with the previous theoretical understanding of these processes, but the zero-energy derivative of the H-3(alpha, gamma)Li-7 S factor is smaller than that in most models. While this method can, in principle, predict cross section normalizations, the normalizations of our results are mostly too low. C1 Univ Chicago, Enrico Fermi Inst, Dept Phys, Chicago, IL 60637 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP CALTECH, MC 130-33, Pasadena, CA 91125 USA. OI Nollett, Kenneth/0000-0002-0671-320X NR 58 TC 57 Z9 57 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2001 VL 63 IS 5 AR 054002 DI 10.1103/PhysRevC.63.054002 PG 13 WC Physics, Nuclear SC Physics GA 431PZ UT WOS:000168640900007 ER PT J AU Sato, T Lee, TSH AF Sato, T Lee, TSH TI Dynamical study of the Delta excitation in N(e,e 'pi) reactions SO PHYSICAL REVIEW C LA English DT Article ID RELATIVIZED QUARK-MODEL; MESON-EXCHANGE MODEL; PION-PHOTOPRODUCTION; GAUGE-INVARIANT; FORM-FACTORS; DELTA(1232) RESONANCE; BARYON RESONANCES; ELECTROPRODUCTION; NUCLEON; AMPLITUDES AB The dynamical model developed by us [Phys. Rev. C 54, 2660 (1996)] has been applied to investigate the pion electroproduction reactions on the nucleon. It is found that the model can describe to a very large extent the recent data of p(e,e' pi (0)). reaction from Jefferson Laboratory and MIT-Bates. The extracted magnetic dipole (MI), electric dipole (E2), and Coulomb (C2) strengths of the gammaN-->Delta transition are presented. It is found that the C2/M1 ratio drops significantly with Q(2) and reaches about - 14% at Q(2) = 4 (GeV/c)(2), while the E2/M1 ratio remains close to the value similar to -3% at the Q(2) = 0 photon point. The determined M1 transition form factor drops faster than the usual dipole form factor of the proton. We also find that the nonresonant interactions can dress the gammaN --> Delta vertex to enhance strongly its strength at low Q(2), but much less at high Q(2) Predictions are presented for future experimental tests. Possible developments of the model are discussed. C1 Osaka Univ, Dept Phys, Osaka 5600043, Japan. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Sato, T (reprint author), Osaka Univ, Dept Phys, Osaka 5600043, Japan. NR 63 TC 187 Z9 187 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2001 VL 63 IS 5 AR 055201 DI 10.1103/PhysRevC.63.055201 PG 13 WC Physics, Nuclear SC Physics GA 431PZ UT WOS:000168640900043 ER PT J AU Stevenson, P Strayer, MR Stone, JR AF Stevenson, P Strayer, MR Stone, JR TI Many-body perturbation calculation of spherical nuclei with a separable monopole interaction SO PHYSICAL REVIEW C LA English DT Article ID MONTE-CARLO CALCULATIONS; GROUND-STATE; EFFECTIVE FORCES; SHELL-MODEL; DRIP LINE; SYSTEMS; MATTER AB We present calculations of ground state properties of spherical, doubly closed-shell nuclei from O-16 to Pb-208 employing the techniques of many-body perturbation theory using a separable density-dependent monopole interaction. The model gives results in Hartree-Fock order that are of similar quality to other effective density-dependent interactions. In addition, second and third order perturbation corrections to the binding energy are calculated and are found to contribute small, but non-negligible corrections beyond the mean-field result, The perturbation series converges quickly, suggesting that this method may be used to calculate fully correlated wave functions with only second or third order perturbation theory. We discuss the quality of the results and suggest possible methods of improvement. C1 Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England. Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. RP Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. RI Stevenson, Paul/B-9016-2012 OI Stevenson, Paul/0000-0003-2645-2569 NR 53 TC 15 Z9 15 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2001 VL 63 IS 5 AR 054309 DI 10.1103/PhysRevC.63.054309 PG 11 WC Physics, Nuclear SC Physics GA 431PZ UT WOS:000168640900017 ER PT J AU Wang, XN AF Wang, XN TI Jet quenching and azimuthal anisotropy of large p(T) spectra in noncentral high-energy heavy-ion collisions SO PHYSICAL REVIEW C LA English DT Article ID RELATIVISTIC NUCLEAR COLLISIONS; ELLIPTIC FLOW; CENTRALITY DEPENDENCE; PB+PB COLLISIONS; PHASE-TRANSITION; GLUON RADIATION; HADRON SPECTRA; AA COLLISIONS; 158A GEV; QCD AB Parton energy loss inside a dense medium leads to the suppression of large p(T) hadrons and can also cause azimuthal anisotropy of hadron spectra at large transverse momentum in noncentral high-energy heavy-ion collisions. Such azimuthal anisotropy is studied qualitatively in a parton model for heavy-ion collisions at RHIC energies. The coefficient upsilon (2)(p(T)) of the elliptic anisotropy at large p(T) is found to be very sensitive to parton energy loss. It decreases slowly with p(T) contrary to its low p(T) behavior where upsilon (2) increases. very rapidly with p(T). The turning point signals the onset of contributions of hard processes and the magnitude of parton energy loss. The centrality dependence of upsilon (2)(p(T)) is shown to be sensitive to both size and density dependence of the parton energy loss and the latter can also be studied via variation of the colliding energy. The anisotropy coefficient upsilon (2)/epsilon normalized by the spatial ellipticity epsilon is found to decrease significantly toward semiperipheral collisions, differing from the hydrodynamic results for low p(T) hadrons. Constrained by the existing WA98 experimental data at the SPS energy on parton energy loss, both hadron spectra suppression and azimuthal anisotropy at high p(T) are predicted to vanish for b > 7 - 8 fm in Au + Au collisions at roots = 130-200 GeV when the hadron rapidity density per unit area of the initial overlapped region is less than what is achieved in the central Pb + Pb collisions at the SPS energy. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Wang, XN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Mailstop 70-319, Berkeley, CA 94720 USA. NR 37 TC 124 Z9 124 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2001 VL 63 IS 5 AR 054902 DI 10.1103/PhysRevC.63.054902 PG 9 WC Physics, Nuclear SC Physics GA 431PZ UT WOS:000168640900037 ER PT J AU Wilson, AN Wadsworth, R Smith, JF Freeman, SJ Leddy, MJ Chiara, CJ Fossan, DB LaFosse, DR Starosta, K Devlin, M Sarantites, DG Wilson, JN Carpenter, MP Davids, CN Janssens, RVF Seweryniak, D Wyss, R AF Wilson, AN Wadsworth, R Smith, JF Freeman, SJ Leddy, MJ Chiara, CJ Fossan, DB LaFosse, DR Starosta, K Devlin, M Sarantites, DG Wilson, JN Carpenter, MP Davids, CN Janssens, RVF Seweryniak, D Wyss, R TI High-spin structures and alignment properties in Ce-126 SO PHYSICAL REVIEW C LA English DT Article ID BACKGROUND SUBTRACTION; OCTUPOLE DEFORMATION; COINCIDENCE DATA; NUCLEI; SHAPE; BANDS; MASS; SPECTROSCOPY; BA-126 AB Excited states in Ce-126 have been observed with the GAMMASPHERE gamma -ray detector array, used in conjunction with the MICROBALL charged-particle detector. The reaction Zn-64(Zn-64, xpn alpha) (beam energy 260 MeV) was used to populate a wide range of nuclei in the neutron-deficient region with A approximate to 120. Ce-126 was populated via the 2p evaporation channel. The three previously observed bands have been extended to higher spins and some other structures have been identified. The yrast band shows evidence of a delayed neutron alignment occurring at a rotational frequency omega approximate to0.5 MeV/(h) over bar as observed in the neighboring odd-A nucleus Pr-127. One of the two excited bands shows evidence for a similar crossing at a slightly lower frequency and also exhibits a sudden gain in alignment at omega =0.57 MeV/(h) over bar. The third band may involve the coupling of a gamma -vibrational state. All three rotational bands are discussed in terms of standard and extended cranked shell model calculations. C1 Univ York, Dept Phys, Heslington YO10 5DD, England. Univ Manchester, Schuster Lab, Manchester MP13 9PL, Lancs, England. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Royal Inst Technol, KTH, S-10405 Stockholm, Sweden. RP Wilson, AN (reprint author), Australian Natl Univ, Res Sch Phys Sci & Engn, Dept Nucl Phys, Canberra, ACT 0200, Australia. RI Freeman, Sean/B-1280-2010; Devlin, Matthew/B-5089-2013; Carpenter, Michael/E-4287-2015; OI Freeman, Sean/0000-0001-9773-4921; Devlin, Matthew/0000-0002-6948-2154; Carpenter, Michael/0000-0002-3237-5734; Wilson, Anna/0000-0001-6928-1689 NR 29 TC 11 Z9 11 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2001 VL 63 IS 5 AR 054307 DI 10.1103/PhysRevC.63.054307 PG 11 WC Physics, Nuclear SC Physics GA 431PZ UT WOS:000168640900015 ER PT J AU Abbott, B Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Balm, PW Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Bassler, U Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F 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 Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Dahl, OI Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Grreenlee, H Grinstein, S Grudberg, P Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hou, S Huang, Y Ito, AS Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, VE Landsberg, G Leflat, A Lehner, F Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Maciel, AKA Madaras, KJ Manankov, V Mani, S Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mostafa, M da Motta, L Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, D Perkins, J Peters, M Peters, O Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Rapidis, P Reay, NW Reucroft, S Rha, J Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sculli, J Sen, N Shabalina, E Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, I Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Z Zanabria, Y Zheng, H Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstein, A AF Abbott, B Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Balm, PW Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Bassler, U Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F 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 Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Dahl, OI Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Grreenlee, H Grinstein, S Grudberg, P Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hou, S Huang, Y Ito, AS Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, VE Landsberg, G Leflat, A Lehner, F Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Maciel, AKA Madaras, KJ Manankov, V Mani, S Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mostafa, M da Motta, L Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, D Perkins, J Peters, M Peters, O Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Rapidis, P Reay, NW Reucroft, S Rha, J Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sculli, J Sen, N Shabalina, E Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, I Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Z Zanabria, Y Zheng, H Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstein, A CA DO Collaboration TI Search for dilepton signatures from minimal low-energy supergravity in p(p)over-bar collisions at root s=1.8 Tev SO PHYSICAL REVIEW D LA English DT Article ID SUPERSYMMETRY; COLLABORATION; NEUTRALINOS; CHARGINOS; PHYSICS; MASS; LEP AB We report on a search for supersymmetry using the D empty set detector. The 1994-1996 data sample of roots = 1.8 TeV p (p) over bar collisions was analyzed for events containing two leptons (e or mu), two or more jets, and missing transverse energy. Assuming the minimal supergravity model, with A(0) = 0 and mu < 0, various thresholds were employed to optimize the search. No events were found beyond expectation from the background. We set a lower limit at the 95% C.L. of 255 GeV/c(2) for equal mass squarks acid gluinos for tan = 2, and present exclusion contours in the (m(0),m(1/2)) plane for tan beta = 2-6. C1 NYU, New York, NY 10003 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 Washington, Seattle, WA 98195 USA. 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, Prague, Czech Republic. Acad Sci Czech Republ, Inst Phys, CR-11142 Prague, Czech Republic. Univ San Francisco Quito, Quito, Ecuador. Univ Grenoble 1, CNRS, IN2P3, Inst Sci Nucl, Grenoble, France. Univ Mediterranee, CNRS, IN2P3, CPPM, Marseille, France. Univ Paris 06, LPNHE, Paris, France. Univ Paris 07, IN2P3, CNRS, Paris, France. CEA, DAPNIA, Serv Phys Particules, Saclay, France. Panjab Univ, Chandigarh, 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, FOM Inst, Amsterdam, Netherlands. Univ Amsterdam, NIKHEF, Amsterdam, Netherlands. Univ Nijmegen, NIKHEF, Nijmegen, Netherlands. Inst Phys Nucl, Krakow, Poland. Inst Theoret & Expt Phys, Moscow 117259, Russia. Moscow State Univ, Moscow, Russia. Inst High Energy Phys, Protvino, Russia. Univ Lancaster, Lancaster, England. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. 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. Univ Hawaii, Honolulu, HI 96822 USA. Fermi 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. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; Santoro, Alberto/E-7932-2014; Peters, Michael/B-4973-2009; Shivpuri, R K/A-5848-2010; 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; Kuleshov, Sergey/D-9940-2013; Canelli, Florencia/O-9693-2016; Belyaev, Alexander/F-6637-2015; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016 OI De, Kaushik/0000-0002-5647-4489; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; Canelli, Florencia/0000-0001-6361-2117; Belyaev, Alexander/0000-0002-1733-4408; Kim, Sun Kee/0000-0002-0013-0775; Sznajder, Andre/0000-0001-6998-1108 NR 22 TC 19 Z9 19 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 2001 VL 63 IS 9 AR 091102 DI 10.1103/PhysRevD.63.091102 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800002 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, A Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Cassada, J 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, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Feretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K 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, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, J Lancaster, M Lander, R Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, V Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Safonov, A St Denis, R Sakumoto, K Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T 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 Taylor, W Tecchio, M Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vataga-Pagliarone, E Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, MJ Watanabe, T Waters, D Watts, T Webb, R 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 Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, A Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Cassada, J 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, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Feretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K 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, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, J Lancaster, M Lander, R Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, V Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Safonov, A St Denis, R Sakumoto, K Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T 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 Taylor, W Tecchio, M Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vataga-Pagliarone, E Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, MJ Watanabe, T Waters, D Watts, T Webb, R 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 Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Search for the supersymmetric partner of the top quark in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW D LA English DT Article ID SCALAR BOTTOM QUARKS; FERMILAB-TEVATRON; STANDARD MODEL; (P)OVER-BAR-P COLLISIONS; HADRONIC COLLISIONS; PAIR PRODUCTION; CROSS-SECTION; SQUARK; LEP; COLLIDER AB We report on a search for the supersymmetric partner of the top quark (top squark) produced in t (t) over bar events using 110 ph(-1) of p (p) over bar collisions at roots = 1.8 TeV recorded with the Collider Detector at Fermilab. In the case of a light top squark, the decay of-the top quark into a top squark plus the lightest supersymmetric particle (LSP) could have a significant branching ratio. The observed events are consistent with standard model t (t) over bar production and decay. Hence, we set limits on the branching ratio of the top quark decaying into a top squark plus LSP, excluding branching ratios above 45% for a LSP mass up to 30 GeV/c(2). C1 Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. Sungkyunkwan Univ, Dept Chem, Suwon 440746, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Kyungpook Natl Univ, Ctr High Energy Phys, Taegu 702701, South Korea. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Illinois, Urbana, IL 61801 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Harvard Univ, Cambridge, MA 02138 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Univ Geneva, CH-1211 Geneva 4, Switzerland. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Florida, Gainesville, FL 32611 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Duke Univ, Durham, NC 27708 USA. Joint Nucl Res Inst, RU-141980 Dubna, Russia. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Cantabria, Inst Fis Cantabria, E-39005 Santander, Spain. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif Davis, Davis, CA 95616 USA. Brandeis Univ, Waltham, MA 02254 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Argonne Natl Lab, Argonne, IL 60439 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. MIT, Cambridge, MA 02139 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 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, Ist Nazl Fis Nucl, 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 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 Affolder, T (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Gorelov, Igor/J-9010-2015; Prokoshin, Fedor/E-2795-2012; Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; vilar, rocio/P-8480-2014; Introzzi, Gianluca/K-2497-2015 OI Gorelov, Igor/0000-0001-5570-0133; Prokoshin, Fedor/0000-0001-6389-5399; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Introzzi, Gianluca/0000-0002-1314-2580 NR 34 TC 9 Z9 9 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 MAY 1 PY 2001 VL 63 IS 9 AR 091101 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800001 ER PT J AU Armstrong, CS Ent, R Keppel, CE Liuti, S Niculescu, G Niculescu, I AF Armstrong, CS Ent, R Keppel, CE Liuti, S Niculescu, G Niculescu, I TI Moments of the proton F-2 structure function at low Q(2) SO PHYSICAL REVIEW D LA English DT Article ID DEUTERON STRUCTURE FUNCTIONS; QUARK-HADRON DUALITY; FORM-FACTORS; PARTON DISTRIBUTIONS; ELECTRON-SCATTERING; ASYMPTOTIC FREEDOM; LOCAL DUALITY; HIGHER TWISTS; LOW-X; RESONANCES AB We investigate the Q(2) dependence of inclusive electron-proton scattering F-2 structure function data in both the nucleon resonance region and the deep inelastic region, at momentum transfers below 5 (GeV/c)(2). From these data we construct moments of F-2, down to momentum transfers of Q(2)approximate to0.1 (GeV/c)(2). The second moment is only slowly varying with Q(2) down to Q(2)approximate to1 (GeV/c)(2), which is a reflection of duality. Below Q(2) of 1 (GeV/c)(2), the Q(2) dependence of the moments is predominantly governed by the elastic contribution, whereas the inelastic channels still seem governed by local duality. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Hampton Univ, Hampton, VA 23668 USA. Univ Virginia, Charlottesville, VA 22901 USA. Ist Nazl Fis Nucl, Sez Roma Tre, Rome, Italy. Ohio Univ, Athens, OH 45071 USA. George Washington Univ, Washington, DC 20052 USA. RP Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. NR 54 TC 47 Z9 47 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 MAY 1 PY 2001 VL 63 IS 9 AR 094008 DI 10.1103/PhysRevD.63.094008 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800017 ER PT J AU Brodsky, SJ Gardi, E Grunberg, G Rathsman, J AF Brodsky, SJ Gardi, E Grunberg, G Rathsman, J TI Disentangling running coupling and conformal effects in QCD SO PHYSICAL REVIEW D LA English DT Article ID ABELIAN GAUGE-THEORIES; BJORKEN SUM-RULE; DRESSED SKELETON EXPANSION; INFRARED FIXED-POINT; TO-LEADING ORDER; QUANTUM CHROMODYNAMICS; PINCH TECHNIQUE; 2 LOOPS; RENORMALIZATION-SCHEME; PERTURBATIVE QCD AB We investigate the relation between a postulated skeleton expansion and the conformal limit of QCD. We begin by developing some consequences of an Abelian-like skeleton expansion, which allows one to disentangle running-coupling effects from the remaining skeleton coefficients. The latter are by construction renormalon free, and hence hopefully better behaved. We consider a simple ansatz fur the expansion, where an observable is written as a sum of integrals over the running coupling. We show that in this framework one can set a unique Brodsky-Lepage-Mackenzie (BLM) scale-setting procedure as an approximation to the running-coupling integrals, where the BLM coefficients coincide with the skeleton ones. Alternatively, the running-coupling integrals can be approximated using the effective charge method. We discuss the limitations in disentangling running coupling effects in the absence of a diagrammatic construction of the skeleton expansion. Independently of the assumed skeleton structure we show that BLM coefficients coincide with conformal coefficients defined in the small beta (0) (Banks-Zaks) limit where a perturbative infrared fixed point is present. This interpretation of the BLM coefficients should explain their previously observed simplicity and smallness. Numerical examples are critically discussed. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Ecole Polytech, Ctr Phys Theor, F-91128 Palaiseau, France. Univ Paris 11, Phys Theor Lab, F-91405 Orsay, France. Univ Paris 11, Phys Theor Lab, F-91405 Orsay, France. CERN, Div TH, CH-1211 Geneva 23, Switzerland. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 69 TC 57 Z9 57 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 MAY 1 PY 2001 VL 63 IS 9 AR 094017 DI 10.1103/PhysRevD.63.094017 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800026 ER PT J AU Burkert, VD AF Burkert, VD TI Generalized Gerasimov-Drell-Hearn sum rule for the proton-neutron difference in chiral perturbation theory SO PHYSICAL REVIEW D LA English DT Article ID SPIN STRUCTURE; Q(2)-DEPENDENCE; EVOLUTION AB Applications of the chiral expansion to generalize the Gerasimov-Drell-Hearn sum rule fur finite Q(2) are discussed. The observation of several authors that the corrections to the leading order contributions are large and limit the applicability to a very small range in Q(2) are only valid when considering the generalization of the sum rule for protons and neutrons separately. When using the proton-neutron difference, the chiral expansion may be valid to considerably higher Q(2) where hadronic degrees of freedom at large distances may connect up with quark and gluon degrees of freedom. This could mark the first time that nucleon structure is described by fundamental theory from large to small distances. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. EM burkert@jlab.org NR 21 TC 32 Z9 32 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 MAY 1 PY 2001 VL 63 IS 9 AR 097904 DI 10.1103/PhysRevD.63.097904 PG 3 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800064 ER PT J AU Chang, D He, XG McKellar, BHJ AF Chang, D He, XG McKellar, BHJ TI Ruling out the Weinberg model of spontaneous CP violation SO PHYSICAL REVIEW D LA English DT Article ID ELECTRIC-DIPOLE MOMENT; HIGGS-BOSON-EXCHANGE; PSEUDOSCALAR MESONS; STANDARD MODEL; GAUGE-THEORY; NEUTRON; NONCONSERVATION; EPSILON'/EPSILON; DECAYS; SECTOR AB There have been many declarations of the death of the Weinberg model of spontaneous CP violation. However, these studies relied on the assumption of unrealistically small errors in the theoretical uncertainties in the calculations of the relevant observables, and a realistic estimate of the errors shows that the Weinberg model cannot be ruled out on the basis used in the past-the experimental values on epsilon in K-0-(K) over bar (0) mixing, the neutron electric dipole moment (EDM), the branching ratio of b-->s gamma, and the earlier upper limit on epsilon'/epsilon. In this paper we use these realistic estimates of the theoretical uncertainty, together with the recent experimental results to study the consistency of the Weinberg model of CP violation with the data. The latest results from Belle and BaBar on sin 2 beta allow the small values of this parameter which occur naturally in the Weinberg model. However, in this model, the recently measured value of Re(epsilon'/epsilon) = (1.92+/-0.25)x10(-3) cannot be made compatible with the branching ratio B(b-->s gamma) = (3.15+/-0.54)x10(-4). As a result we conclude that the Weinberg model is now confidently and conservatively ruled out. C1 Natl Tsing Hua Univ, Dept Phys, Hsinchu 300, Taiwan. SLAC, Stanford, CA 94309 USA. Natl Taiwan Univ, Dept Phys, Taipei 10617, Taiwan. Univ Melbourne, Sch Phys, Parkville, Vic 3052, Australia. RP Natl Tsing Hua Univ, Dept Phys, Hsinchu 300, Taiwan. RI He, Xiao-Gang/C-8894-2013; He, Xiao-Gang/P-2242-2015 NR 53 TC 7 Z9 7 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 MAY 1 PY 2001 VL 63 IS 9 AR 096005 DI 10.1103/PhysRevD.63.096005 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800052 ER PT J AU Chang, D Chang, WF Chou, CH Keung, WY AF Chang, D Chang, WF Chou, CH Keung, WY TI Large two-loop contributions to g-2 from a generic pseudoscalar boson SO PHYSICAL REVIEW D LA English DT Article ID ANOMALOUS MAGNETIC-MOMENT; ELECTRIC-DIPOLE MOMENT; SUPERSYMMETRIC STANDARD MODEL; MUON G-2; HIGGS BOSONS; SUPERGRAVITY; CONSTRAINTS; NEUTRON; VIOLATION; (G-2)(MU) AB We calculate the dominant contributions to the muon g-2 at the two-loop level due to a generic pseudoscalar boson that may exist in any exotic Higgs sector in most extensions of the standard model. The leading effect comes from diagrams of the Barr-Zee type. A sufficiently light pseudoscalar Higgs boson can give rise to contributions as large as the electroweak contribution which is measurable in the next round of g-2 experiments. Through the contribution we calculate here, the anticipated improved data in the recent future on the muon g-2 can put the best limit on the possible existence of a light pseudoscalar boson in physics beyond the standard model. C1 Natl Tsing Hua Univ, NCTS, Hsinchu 30043, Taiwan. Natl Tsing Hua Univ, Dept Phys, Hsinchu 30043, Taiwan. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RP Natl Tsing Hua Univ, NCTS, Hsinchu 30043, Taiwan. NR 55 TC 58 Z9 58 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 MAY 1 PY 2001 VL 63 IS 9 AR 091301 DI 10.1103/PhysRevD.63.091301 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800003 ER PT J AU Chodos, A Cooper, F Mao, WJ Singh, A AF Chodos, A Cooper, F Mao, WJ Singh, A TI Equilibrium and nonequilibrium properties associated with the chiral phase transition at finite density in the Gross-Neveu model SO PHYSICAL REVIEW D LA English DT Article ID CENTRAL RAPIDITY REGION; STRONG ELECTRIC-FIELD; COLOR SUPERCONDUCTIVITY; PARTICLE-PRODUCTION; SYMMETRY-BREAKING; QUARK MATTER; RENORMALIZATION-GROUP; PAIR PRODUCTION; BARYON DENSITY; TEMPERATURE AB We study the dynamics of the chiral phase transition at finite density in the Gross-Neveu (GN) model in the leading order in the large-hi approximation. The phase structure of the GN model in this approximation has the property that there is a tricritical point at a fixed temperature and chemical potential separating regions where the chiral transition is first order from that where it is second order. We consider evolutions starting in local thermal and chemical equilibrium in the massless unbroken phase for conditions pertaining to traversing a first or second order phase transition. We assume boost invariant kinematics and determine the evolution of the order parameter sigma, the energy density and pressure as well as the effective temperature, chemical potential and interpolating number densities as a function of the proper time tau. We find that before the phase transition, the system behaves as if it were an ideal fluid in local thermal equilibrium with equation of state p = epsilon. After the phase transition, the system quickly reaches its true broken symmetry vacuum value for the fermion mass and for the energy density. The single particle distribution functions for fermions and antifermions go far out of equilibrium as soon as the plasma traverses the chiral phase transition. We have also determined the spatial dependence of the "pion" Green's function [<()over bar>(x) gamma (5)psi (x)<()over bar>(0) gamma (5)psi (0)] as a function of the proper time. C1 Amer Phys Soc, College Pk, MD 20740 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Boston Coll, Dept Phys, Chestnut Hill, MA 02167 USA. RP Chodos, A (reprint author), Amer Phys Soc, 1 Phys Ellipse, College Pk, MD 20740 USA. EM chodos@aps.org; cooper@schwinger.lanl.gov; maow@physics.rutgers.edu; singh@lanl.gov NR 58 TC 13 Z9 13 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 MAY 1 PY 2001 VL 63 IS 9 AR 096010 DI 10.1103/PhysRevD.63.096010 PG 24 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800057 ER PT J AU Edwards, RG Heller, UM AF Edwards, RG Heller, UM TI Domain wall fermions with exact chiral symmetry SO PHYSICAL REVIEW D LA English DT Article ID OVERLAP DIRAC OPERATOR; LATTICE QCD; GAUGE-THEORIES; QUENCHED QCD; QUARKS AB We show how the standard domain wall action can be simply modified to allow arbitrarily exact chiral symmetry at a finite fifth dimensional extent. We note that the method can be used for both quenched and dynamical calculations. We test the method using smooth and thermalized gauge field configurations. We also make comparisons of the performance (cost) of the domain wall operator for spectroscopy compared to other methods such as the overlap-Dirac operator and find both methods are comparable in cost. C1 Jefferson Lab, Newport News, VA 23606 USA. Florida State Univ, Computat Sci & Informat Technol, Tallahassee, FL 32306 USA. RP Edwards, RG (reprint author), Jefferson Lab, 12000 Jefferson Ave,MS 12H2, Newport News, VA 23606 USA. OI Heller, Urs M./0000-0002-2780-5584 NR 35 TC 25 Z9 25 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 2001 VL 63 IS 9 AR 094505 DI 10.1103/PhysRevD.63.094505 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800036 ER PT J AU Gluck, M Reya, E Stratmann, M Vogelsang, W AF Gluck, M Reya, E Stratmann, M Vogelsang, W TI Models for the polarized parton distributions of the nucleon SO PHYSICAL REVIEW D LA English DT Article ID DEEP-INELASTIC-SCATTERING; TO-LEADING-ORDER; NEUTRON SPIN STRUCTURE; LIGHT-QUARK SEA; STRUCTURE-FUNCTION G(1)(N); OPPOSITE-SIGN DIMUONS; N-C LIMIT; QCD ANALYSIS; FLAVOR-ASYMMETRY; ANTIQUARK DISTRIBUTIONS AB Polarized deep inelastic scattering (DIS) data are analyzed in leading and next-to-leading order of QCD within the common "standard" scenario of polarized parton distributions with a flavor-symmetric light sea (antiqualk) distribution delta(q) over bar, and a completely SU(3)(f) broken "valence" scenario with totally flavor-asymmetric light sea densities (delta(u) over bar not equal delta(d) over bar not equal delta(s) over bar). The latter flavor-broken light sea distributions are modeled with the help of a Pauli-blocking ansatz at the low radiative or dynamical input scales of mu (2)(LO(NLO)) = 0.26 (0.40) GeV2 which complies with predictions of the chiral quarh;-soliton model and expectations based on the statistical parton model as well as with the corresponding, well established, flavor-broken unpolarized sea ((d) over bar><()over bar>). Present semi-inclusive DIS data cannot yet uniquely discriminate between those two flavor-symmetric and flavor-broken polarized light sea scenarios. C1 Univ Dortmund, Inst Phys, D-44221 Dortmund, Germany. Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Gluck, M (reprint author), Univ Dortmund, Inst Phys, D-44221 Dortmund, Germany. NR 89 TC 444 Z9 445 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 2001 VL 63 IS 9 AR 094005 DI 10.1103/PhysRevD.63.094005 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800014 ER PT J AU Jalilian-Marian, J Wang, XN AF Jalilian-Marian, J Wang, XN TI Shadowing of gluons in perturbative QCD: A comparison of different models SO PHYSICAL REVIEW D LA English DT Article ID WILSON RENORMALIZATION-GROUP; LOW X PHYSICS; HIGH-DENSITY; LARGE NUCLEI; SMALL VALUES; SCATTERING; EVOLUTION; DISTRIBUTIONS; SATURATION; REGIME AB We investigate the different perturbative QCD-based models for nuclear shadowing of gluons. We show that, in the kinematic region appropriate to the BNL relativistic heavy ion collider experiment, all models give similar estimates for the magnitude of gluon shadowing. At scales relevant to CERN large hadron collider (LHC), there is a sizable difference between the predictions of the different models. However, the uncertainties in gluon shadowing coming from a different parametrization of the gluon distribution in nucleons, are larger than those due to different perturbative QCD models of gluon shadowing. We also investigate the effect of initial nonperturbative shadowing on the magnitude of perturbative shadowing and show that the magnitudes of perturbative and nonperturbative shadowing are comparable at RHIC but perturbative shadowing dominates over nonperturbative shadowing at smaller values of x reached at LHC. C1 Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Jalilian-Marian, J (reprint author), Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. NR 35 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 2001 VL 63 IS 9 AR 096001 DI 10.1103/PhysRevD.63.096001 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800048 ER PT J AU Mihaila, B Dawson, JF Cooper, F AF Mihaila, B Dawson, JF Cooper, F TI Resumming the large-N approximation for time evolving quantum systems SO PHYSICAL REVIEW D LA English DT Article ID SCALAR FIELD; EVOLUTION; DYNAMICS; EXPANSION; THERMALIZATION; RELAXATION AB In this paper we discuss two methods of resumming the leading and next to leading order in 1/N diagrams fur the quartic O(N) model. These two approaches have the property that they preserve both boundedness and positivity for expectation values of operators in our numerical simulations. These approximations can be understood either in terms of a truncation to the infinitely coupled Schwinger-Dyson hierarchy of equations, or by choosing a particular two-particle irreducible vacuum energy graph in the effective action of the Cornwall-Jackiw-Tomboulis formalism. We confine our discussion to the case of quantum mechanics where the Lagrangian is L(x,(x) over dot) = (1/2)Sigma (N)(i) = 1(x) over dot (2)(i)-(g/8N)[Sigma (N)(i) = (1)x(i)(2)- r(0)(2)](2). The key to these approximations is to treat both the x propagator and the x(2) propagator on similar footing which leads to a theory whose graphs have the same topology as QED with the x(2) propagator playing the role of the photon. The bare vertex approximation is obtained by replacing the exact vertex function by the bare one in the exact Schwinger-Dyson equations for the one and two point functions. The second approximation, which we call the dynamic Debye screening approximation, makes the further approximation of replacing the exact x(2) propagator by its value at leading order in the 1/N expansion. These two approximations are compared with tract numerical simulations for the quantum roll problem. The bare vertex approximation captures the physics at large and modest N better than the dynamic Debye screening approximation. C1 Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Mihaila, B (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. EM bogdan.mihaila@unh.edu; john.dawson@unh.edu; cooper@schwinger.lanl.gov RI Mihaila, Bogdan/D-8795-2013 OI Mihaila, Bogdan/0000-0002-1489-8814 NR 54 TC 51 Z9 51 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 MAY 1 PY 2001 VL 63 IS 9 AR 096003 DI 10.1103/PhysRevD.63.096003 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800050 ER PT J AU Wingate, M Ohta, S AF Wingate, M Ohta, S TI Deconfinement transition and string tensions in SU(4) Yang-Mills theory SO PHYSICAL REVIEW D LA English DT Article ID LATTICE GAUGE-THEORY; QCD PHASE-TRANSITION; FINITE-TEMPERATURE; LATENT-HEAT; MONTE-CARLO; QUARK; THERMODYNAMICS; CONFINEMENT; FIELDS AB We present results from numerical lattice calculations of SU(4) Yang-Mills theory. This work has two goals: to determine the order of the finite temperature deconfinement transition on an N-t=6 lattice and to study the string tensions between static charges in the irreducible representations of SU(4). Motivated by the argument of Pisarski and Tytgat that a second-order SU(infinity) deconfinement transition would explain some features of the SU(3) and QCD transitions, we confirm older results on a coarser, N-t=4, lattice. We see a clear two-phase coexistence signal in the order parameter, characteristic of a first-order transition, at 8/g(2)=10.79 on a 6 x 20(3) lattice, on which we also compute a latent heat of Delta epsilon approximate to0.6 epsilon (SB). Computing Polyakov loop correlation functions, we calculate the string tension at finite temperature in the confined phase between fundamental charges sigma (1), between diquark charges sigma (2), and between adjoint charges sigma (4). We find that 1<(2)/sigma (1)<2. and our result for the adjoint string tension (4) is consistent with string breaking. C1 Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. KEK, Inst Nucl & Particle Phys, Ibaraki, Osaka 3050801, Japan. RP Wingate, M (reprint author), Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. OI Wingate, Matthew/0000-0001-6568-988X NR 46 TC 23 Z9 23 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 2001 VL 63 IS 9 AR 094502 DI 10.1103/PhysRevD.63.094502 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 428FJ UT WOS:000168450800033 ER PT J AU Forsman, AC Kyrala, GA AF Forsman, AC Kyrala, GA TI Non-Doppler shift related experimental shock wave measurements using velocity interferometer systems for any reflector SO PHYSICAL REVIEW E LA English DT Article ID LASER AB Velocity interferometer system for any reflectors (VISARs), are becoming increasingly popular in the measurement of shack waves in solids and liquids. VISAR techniques are used in measurements of transit time, speed of shock waves in flight in transparent media [L. C. Chhabildas and J. L. Wise, in Proceedings of the 4th APS Topical Conference on Shock Waves in Condensed Matter; Spokane, Washington, 1985, edited by Y, M. Gupta (Plenum, New York, 1986); P. M. Celliers ei al.: Appl. Phys. Lett. 73, 1320 (1998)], and in measurements of particle velocity. However, in cases where shock compression or release may change the index of refraction n + ik of the material being studied, the VISAR technique must be applied with care. Changes in a and k introduce phase shifts into the VISAR results that are not associated with changes in velocity. This paper presents a derivation of the theoretical output of a line VISAR that includes the effects of changing n and k and an experimental observation of a non-Doppler shift related effect. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Forsman, AC (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 11 TC 9 Z9 9 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2001 VL 63 IS 5 AR 056402 DI 10.1103/PhysRevE.63.056402 PN 2 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 432ZL UT WOS:000168730800069 PM 11415014 ER PT J AU Howell, DW Aronson, IS Crabtree, GW AF Howell, DW Aronson, IS Crabtree, GW TI Dynamics of electrostatically driven granular media: Effects of humidity SO PHYSICAL REVIEW E LA English DT Article ID TRANSITIONS; GASES; FLOWS AB We performed experimental studies of the effect of humidity on the dynamics of electrostatically driven granular materials. Both conducting and dielectric particles undergo a phase transition from an immobile state (granular solid) to a fluidized state (granular gas) with increasing applied field. Spontaneous precipitation of solid clusters from the gas phase occurs as the external driving is decreased. The clustering dynamics in conducting particles is primarily controlled by screening of the electric field but is aided by cohesion due to humidity. it is shown that humidity effects dominate the clustering process with dielectric particles. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Howell, DW (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 25 TC 15 Z9 15 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2001 VL 63 IS 5 AR 050301 DI 10.1103/PhysRevE.63.050301 PN 1 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 432ZK UT WOS:000168730700002 PM 11414879 ER PT J AU Kane, JO Robey, HF Remington, BA Drake, RP Knauer, J Ryutov, DD Louis, H Teyssier, R Hurricane, O Arnett, D Rosner, R Calder, A AF Kane, JO Robey, HF Remington, BA Drake, RP Knauer, J Ryutov, DD Louis, H Teyssier, R Hurricane, O Arnett, D Rosner, R Calder, A TI Interface imprinting by a rippled shock using an intense laser SO PHYSICAL REVIEW E LA English DT Article ID INSTABILITY GROWTH; HYDRODYNAMICS; SUPERNOVA; SYSTEM; OMEGA; SIMULATION; COLLAPSE; CORE AB Perturbation imprinting at a flat interface by a rippled shock has been observed in a laser hydrodynamics experiment. A strong shock was driven through a three-layer target, with the first interface rippled, and the second flat. The chosen thickness of the second layer gave instability growth with opposite phases at the two interfaces, consistent with two-dimensional simulations and rippled shock theory. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Michigan, Ann Arbor, MI 48105 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. CEA, Saclay, France. Univ Arizona, Tucson, AZ USA. Univ Chicago, Chicago, IL 60637 USA. RP Kane, JO (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Calder, Alan/E-5348-2011; Drake, R Paul/I-9218-2012 OI Drake, R Paul/0000-0002-5450-9844 NR 24 TC 38 Z9 40 U1 1 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2001 VL 63 IS 5 AR 055401 DI 10.1103/PhysRevE.63.055401 PN 2 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 432ZL UT WOS:000168730800008 PM 11414953 ER PT J AU Wang, CX Kim, KJ AF Wang, CX Kim, KJ TI Recursive solution for beam dynamics of periodic focusing channels SO PHYSICAL REVIEW E LA English DT Article AB We present recursive analysis for beam dynamics of pel-iodic focusing channels based on the Fourier coefficients of the focusing function. Formulas for orbit stability and the envelope function are derived. The results should be useful for numerical calculation and for developing analytical understanding of channels employing extended focusing elements. Applications to muon ionization cooling channels are discussed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Chicago, Chicago, IL 60637 USA. RP Wang, CX (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 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 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2001 VL 63 IS 5 AR 056502 PN 2 PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 432ZL UT WOS:000168730800078 ER PT J AU Zilberman, S Persson, BNJ Nitzan, A Mugele, F Salmeron, M AF Zilberman, S Persson, BNJ Nitzan, A Mugele, F Salmeron, M TI Boundary lubrication: Dynamics of squeeze-out SO PHYSICAL REVIEW E LA English DT Article ID CURVED SOLID-SURFACES; LONG-RANGE ELASTICITY; LAYERING TRANSITION; THIN-FILMS; SIMPLE LIQUIDS; GROWTH; FRICTION; SHEAR AB The dynamics of the expulsion of the last liquid monolayer of molecules confined between two surfaces (measured recently for the first time) has been analyzed by solving the two-dimensional Navier-Stokes equation combined with kinetic Monte Carlo simulations. Instabilities in the boundary line of the expelled film were observed. We show that the instabilities produce a rough boundary for all length scales above a critical value and a smooth boundary for shorter lengths. The squeezing out of all but a few trapped islands of liquid is shown to be the result of the pressure gradient in the contact area. C1 Tel Aviv Univ, Sch Chem, IL-69978 Tel Aviv, Israel. Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Tel Aviv Univ, Sch Chem, IL-69978 Tel Aviv, Israel. RI Abraham, Nitzan/A-9963-2008; Persson, Bo Nils Johan/I-1548-2013; Mugele, Frieder/A-5225-2017 OI Persson, Bo Nils Johan/0000-0003-1535-738X; Mugele, Frieder/0000-0003-3824-3617 NR 24 TC 20 Z9 20 U1 1 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2001 VL 63 IS 5 AR 055103 DI 10.1103/PhysRevE.63.055103 PN 2 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 432ZL UT WOS:000168730800003 PM 11414948 ER PT J AU Arp, U Fraser, GT Walker, ARH Lucatorto, TB Lehmann, KK Harkay, K Sereno, N Kim, KJ AF Arp, U Fraser, GT Walker, ARH Lucatorto, TB Lehmann, KK Harkay, K Sereno, N Kim, KJ TI Spontaneous coherent microwave emission and the sawtooth instability in a compact storage ring SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID SYNCHROTRON RADIATION; MILLIMETER WAVELENGTHS; BUNCH; SUBMILLIMETER AB Strong evidence for self-excited emission of coherent synchrotron radiation in the microwave spectral region was observed at the Synchrotron Ultraviolet Radiation Facility (SURF III) electron storage ring at the NIST. The microwave emission between 25 and 35 mm was dominated by intense bursts of radiation. The intensity enhancement during these bursts was on the order of 10 000 to 50 000 over the incoherent value. The shape, width, and period of the bursts depend strongly on the operational parameters of the storage ring. Coherent microwave emission was observed only when the beam was unstable, namely, during bunch-length relaxation oscillations. We report on the measurements of the microwave bursts, and correlate the data with signals from a beam monitor electrode and photodiode detector. The coherent enhancement of the radiation intensity is ascribed to spontaneous self-induced microbunching of the electrons within the bunch. C1 Natl Inst Stand & Technol, Phys Lab, Gaithersburg, MD 20899 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Arp, U (reprint author), Natl Inst Stand & Technol, Phys Lab, Gaithersburg, MD 20899 USA. RI Arp, Uwe/C-2854-2009; Hight Walker, Angela/C-3373-2009 OI Hight Walker, Angela/0000-0003-1385-0672 NR 37 TC 29 Z9 29 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD MAY PY 2001 VL 4 IS 5 AR 054401 DI 10.1103/PhysRevSTAB.4.054401 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 461MM UT WOS:000170368100004 ER PT J AU Elmer, JW Klingmann, J Van Bibber, K AF Elmer, JW Klingmann, J Van Bibber, K TI Diffusion bonding and brazing of high purity copper for linear collider accelerator structures SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID KINETICS AB Diffusion bonding and brazing of high purity copper were investigated to develop procedures for joining precision machined copper components for the Next Linear Collider (NLC). Diffusion bonds were made over a range of temperatures from 400 degreesC to 1000 degreesC, under two different loading conditions [3.45 kPa (0.5 psi) and 3.45 MPa (500 psi)], and on two different diamond machined surface finishes. Brazes were made using pure silver, pure gold, and gold-nickel alloys, and different heating rates produced by both radiation and induction heating. Braze materials were applied by both physical vapor deposition (PVD) and conventional braze alloy shims. Results of the diffusion bonding experiments showed that bond strengths very near that of the copper base metal could be made at bonding temperatures of 700 degreesC or higher at 3.45 MPa bonding pressure. At lower temperatures, only partial strength diffusion bonds could be made. At low bonding pressures (3.45 kPa), full strength bonds were made at temperatures of 800 degreesC and higher, while no bonding (zero strength) was observed at temperatures of 700 degreesC and lower. Observations of the fracture surfaces of the diffusion bonded samples showed the effects of surface finish on the bonding mechanism. These observations clearly indicate that bonding began by point asperity contact, and flatter surfaces resulted in a higher percentage of bonded area under similar bonding conditions. Results of the brazing experiments indicated that pure silver worked very well for brazing under both conventional and high heating rate scenarios. Similarly, pure silver brazed well for both the PVD layers and the braze alloy shims. The gold and gold-containing brazes had problems, mainly due to the high diffusivity of gold in copper. These problems led to the necessity of overdriving the temperature to ensure melting, the presence of porosity in the joint, and very wide braze joints. Based on the overall findings of this study, a two-step joining method is proposed for fabricating the NLC structures. The structure would be assembled with pure silver braze inserts using a self-aligning step joint design, then the assembly would be vacuum diffusion bonded at 700 degreesC and 3.45 MPa pressure to seal the critical inner portion of the assembly. Finally, during the same furnace cycle, the temperature would be increased to 800 degreesC in order to react the silver with the copper to form a liquid braze alloy that would join and seal the outer portion of the cells together. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Elmer, JW (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 17 TC 0 Z9 0 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD MAY PY 2001 VL 4 IS 5 AR 053502 DI 10.1103/PhysRevSTAB.4.053502 PG 16 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 461MM UT WOS:000170368100003 ER PT J AU Lin, XE AF Lin, XE TI Photonic band gap fiber accelerator SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID OPTICAL FIBERS; GUIDANCE; LIGHT; AIR AB There are three requirements in making a traveling wave accelerator: longitudinal electric field, synchronization, and confinement. We present and analyze a conceptually new kind of charged particle accelerator, making use of a photonic band gap lattice for field confinement near the beam axis, and employing dielectric material to produce a speed of light synchronous longitudinal electric field. An example structure design is presented. We also discuss nonlinear effect and other configurations without higher order dipole modes. Parallel scheme and fabrication are presented. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Lin, XE (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 24 TC 94 Z9 94 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD MAY PY 2001 VL 4 IS 5 AR 051301 DI 10.1103/PhysRevSTAB.4.051301 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 461MM UT WOS:000170368100001 ER PT J AU Son, DT Stephanov, MA AF Son, DT Stephanov, MA TI QCD at a finite isospin density: Front the pion to quark-antiquark condensation SO PHYSICS OF ATOMIC NUCLEI LA English DT Article ID STRONG COUPLING LIMIT; COLOR-FLAVOR-LOCKING; LATTICE SU(N) QCD; BARYON DENSITY; QUANTUM CHROMODYNAMICS; MASS INEQUALITIES; MATTER; SUPERCONDUCTIVITY; TEMPERATURE; PHASE AB QCD at a finite isospin chemical potential mu (I) is studied. This theory has no fermion-sign problem and can be simulated on a lattice by using present-day techniques. We solve this theory analytically in two limits: low mu (I) where chiral perturbation theory is applicable, and asymptotically high mu (I), where perturbative QCD is at work. At a low isospin density, the ground state is a superfluid pion condensate. At a very high density, it is a Fermi liquid with Cooper pairing. The pairs carry the same quantum numbers as the pions. Motivated by this observation, we put forward a conjecture that the transition from hadron to quark matter is smooth. The conjecture passes several nontrivial tests. Our results imply a nontrivial phase diagram in the space of the temperature and chemical potentials of isospin and baryon number. At asymptotically large values of mu (I) and small values of the baryon chemical potential, the ground state is in a phase similar to the Fulde-Ferrell-Larkin-Ovchinniltov phase, It is characterized by a spatially modulated superfluid order parameter <(u) over bar gamma (5)d > and may be the asymptotic limit of the inhomogeneous pion-condensation phase advocated by Migdal and others. (C) 2001 MAIK "Nauka/Interperiodica". C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RIKEN, BNL, Res Ctr, Brookhaven Natl Lab, Upton, NY 11973 USA. RP Son, DT (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. NR 46 TC 104 Z9 104 U1 0 U2 0 PU MAIK NAUKA/INTERPERIODICA/SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013-1578 USA SN 1063-7788 EI 1562-692X J9 PHYS ATOM NUCL+ JI Phys. Atom. Nuclei PD MAY PY 2001 VL 64 IS 5 BP 834 EP 842 DI 10.1134/1.1378872 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 449ZC UT WOS:000169716200004 ER PT J AU Fast, P Kondic, L Shelley, MJ Palffy-Muhoray, P AF Fast, P Kondic, L Shelley, MJ Palffy-Muhoray, P TI Pattern formation in non-Newtonian Hele-Shaw flow SO PHYSICS OF FLUIDS LA English DT Article ID SAFFMAN-TAYLOR INSTABILITY; VISCOUS FINGERING PATTERNS; SHEAR-THINNING FLUID; SURFACE-TENSION; 2-PHASE DISPLACEMENT; VISCOELASTIC FLUID; POLYMER-SOLUTIONS; LIQUID-CRYSTALS; CELL; BEHAVIOR AB We study theoretically the Saffman-Taylor instability of an air bubble expanding into a non-Newtonian fluid in a Hele-Shaw cell, with the motivation of understanding suppression of tip-splitting and the formation of dendritic structures observed in the flow of complex fluids, such as polymeric liquids or liquid crystals. A standard visco-elastic flow model is simplified in the case of flow in a thin gap, and it is found that there is a distinguished limit where shear thinning and normal stress differences are apparent, but elastic response is negligible. This observation allows formulation of a generalized Darcy's law, where the pressure satisfies a nonlinear elliptic boundary value problem. Numerical simulation shows that shear-thinning alone modifies considerably the pattern formation and can produce fingers whose tip-splitting is suppressed, in agreement with experimental results. These fingers grow in an oscillating fashion, shedding "side-branches" from their tips, closely resembling solidification patterns. A careful analysis of the parametric dependencies of the system provides an understanding of the conditions required to suppress tip-splitting, and an interpretation of experimental observations, such as emerging length-scales. (C) 2001 American Institute of Physics. C1 NYU, Courant Inst Math Sci, New York, NY 10012 USA. New Jersey Inst Technol, Dept Math Sci, Newark, NJ 07102 USA. New Jersey Inst Technol, Ctr Appl Math & Stat, Newark, NJ 07102 USA. Kent State Univ, Inst Liquid Crystal, Kent, OH 44242 USA. RP Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 808,L-661, Livermore, CA 94551 USA. NR 67 TC 44 Z9 44 U1 1 U2 16 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-6631 EI 1089-7666 J9 PHYS FLUIDS JI Phys. Fluids PD MAY PY 2001 VL 13 IS 5 BP 1191 EP 1212 DI 10.1063/1.1359417 PG 22 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 420ZU UT WOS:000168037200012 ER PT J AU Nadiga, BT Shkoller, S AF Nadiga, BT Shkoller, S TI Enhancement of the inverse-cascade of energy in the two-dimensional Lagrangian-averaged Navier-Stokes equations SO PHYSICS OF FLUIDS LA English DT Article ID HYDRODYNAMICS; MOTION; MODEL; FLUID AB The recently derived Lagrangian-averaged Navier-Stokes equations model the large-scale flow of the Navier-Stokes fluid at spatial scales larger than some a priori fixed alpha >0, while coarse-graining the behavior of the small scales. In this communication, we numerically study the behavior of the two-dimensional (2D) isotropic version of this model, also known as the alpha model. The inviscid dynamics of this model exactly coincide with the vortex blob algorithm for a certain choice of smoothing kernel, as well as the equations of an inviscid second-grade non-Newtonian fluid. While previous studies of this system in 3D have noted the suppression of nonlinear interaction between modes smaller than alpha, we show that the modification of the nonlinear advection term also acts to enhance the inverse-cascade of energy in 2D turbulence and thereby affects scales of motion larger than alpha as well. This, we note, (a) may preclude a straightforward use of the model as a subgrid model in coarsely resolved 2D computations, (b) is reminiscent of the drag-reduction that occurs in a turbulent flow when a dilute polymer is added, and (c) can be qualitatively understood in terms of known dimensional arguments. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Davis, Dept Math, Davis, CA 95616 USA. RP Nadiga, BT (reprint author), Univ Calif Los Alamos Natl Lab, MS-B296, Los Alamos, NM 87545 USA. NR 15 TC 19 Z9 19 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD MAY PY 2001 VL 13 IS 5 BP 1528 EP 1531 DI 10.1063/1.1359764 PG 4 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 420ZU UT WOS:000168037200040 ER PT J AU Akushevich, I Kuraev, E Shaikhatdenov, B AF Akushevich, I Kuraev, E Shaikhatdenov, B TI QED effects of higher orders in DIS SO PHYSICS OF PARTICLES AND NUCLEI LA English DT Article ID DEEP-INELASTIC-SCATTERING; ANGLE BHABHA SCATTERING; STRUCTURE-FUNCTION G(1)(N); LEPTON-NUCLEON-SCATTERING; 2 HARD PHOTONS; RADIATIVE-CORRECTIONS; SPIN STRUCTURE; HIGH-ENERGIES; ELECTROMAGNETIC CORRECTIONS; POLARIZED PARTICLES AB The present status of the theoretical description of the deep inelastic scattering of leptons off protons with account for radiative corrections (RCs) in the leading and next-to-leading approximations are reviewed. For the process ep --> ep gamma along with RC coming from the emission of virtual, soft, and additional hard photons, it has been considered an e(+)e(-) pair production in the leading approximation. The Compton tensor with a heavy photon in the case of a longitudinally polarized electron is presented. A cross section for a special experimental setup with the tagging of an additional hard photon is given to the nonleading order. A similar consideration is carried out fur a cross channel, namely, electron-positron annihilation into hadrons with the emission of a hard photon by initial leptons. The details of calculations are given in the appendices. C1 N Carolina Cent Univ, Durham, NC 27707 USA. TJNAF, Newport News, VA 23606 USA. Joint Inst Nucl Res, Dubna 141980, Moscow Oblast, Russia. RP Akushevich, I (reprint author), N Carolina Cent Univ, Durham, NC 27707 USA. NR 81 TC 2 Z9 2 U1 0 U2 1 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 1063-7796 J9 PHYS PART NUCLEI JI Phys. Part. Nuclei PD MAY-JUN PY 2001 VL 32 IS 3 BP 257 EP 285 PG 29 WC Physics, Particles & Fields SC Physics GA 442FE UT WOS:000169273900001 ER PT J AU Lin, ZH Chen, L AF Lin, ZH Chen, L TI A fluid-kinetic hybrid electron model for electromagnetic simulations SO PHYSICS OF PLASMAS LA English DT Article ID ENERGETIC PARTICLES; TOKAMAKS; INSTABILITIES; TURBULENCE; PLASMAS; WAVES; FLOWS AB A fluid-kinetic hybrid electron model for electromagnetic simulations of finite-beta plasmas is developed based on an expansion of the electron response using the electron-ion mass ratio as a small parameter. (Here beta is the ratio of plasma pressure to magnetic pressure.) The model accurately recovers low frequency plasma dielectric responses and faithfully preserves nonlinear kinetic effects (e.g., phase space trapping). Maximum numerical efficiency is achieved by overcoming the electron Courant condition and suppressing high frequency modes. This method is most useful for nonlinear kinetic (particle-in-cell or Vlasov) simulations of electromagnetic microturbulence and Alfvenic instabilities in magnetized plasmas. (C) 2001 American Institute of Physics. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. RP Lin, ZH (reprint author), Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RI chen, liu/I-2297-2013 NR 19 TC 71 Z9 71 U1 0 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1447 EP 1450 DI 10.1063/1.1356438 PN 1 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800001 ER PT J AU Cohen, RH Ryutov, DD AF Cohen, RH Ryutov, DD TI Discrete symmetries in axisymmetric toroidal plasma confinement SO PHYSICS OF PLASMAS LA English DT Article AB Several discrete symmetry parameters characterizing axisymmetric toroidal plasmas have been introduced. For a device without up-down symmetry such parameters are S-1, related to the handedness of the toroidal current, S-2, related to the direction of the toroidal velocity, and S-3, characterizing the handedness of the toroidal magnetic field. All these parameters can acquire values +/-1, thereby making eight different combinations. For a device with up-down symmetry only the mutual orientation of the toroidal current, toroidal velocity, and toroidal magnetic field remain important. Based on the general expression for the Lagrangian for charged particles in an external magnetic field, we identify the invariance properties of this Lagrangian (and, accordingly, of plasma behavior) with respect to these transformations. Reduced plasma models, based on the Maxwell-Boltzmann equations, and on the magnetohydrodynamic equations, are also considered. An analysis of the plasma behavior in the context of the symmetry properties may be helpful in identifying the most probable theoretical models of plasma transport. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Cohen, RH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 8 TC 8 Z9 8 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1451 EP 1454 DI 10.1063/1.1357217 PN 1 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800002 ER PT J AU Nebel, RA Finn, JM AF Nebel, RA Finn, JM TI Fluid and kinetic stability of virtual cathodes for the periodically oscillating plasma sphere SO PHYSICS OF PLASMAS LA English DT Article ID ELECTRON PENNING TRAP; DENSITY; FOCUS AB Recent theoretical work [R. A. Nebel and D. C. Barnes, Fusion Technol. 38, 28 (1998); D. C. Barnes and R. A. Nebel, Phys. Plasmas 5, 2498 (1998)] has suggested that a tiny oscillating ion cloud (referred to as the periodically oscillating plasma sphere or POPS) may undergo a self-similar collapse that can result in the periodic and simultaneous attainment of ultrahigh densities and temperatures. However, a major uncertainty in this plasma system is the behavior of the electron cloud that forms a virtual cathode. Here it is demonstrated that the required electron cloud (which forms a harmonic oscillator potential) is susceptible to an instability related to buoyancy-driven modes present in compressible fluids. Although it is demonstrated that no absolutely stable profiles with uniform electron density exist, stable profiles that are close to the required harmonic oscillator potential are found. A simple two-stream analysis indicates that kinetic effects lead to a critical limit in lambda (D)/a above which the virtual cathodes are stable. This result is consistent with previous experimental observations. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Nebel, RA (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS K717, Los Alamos, NM 87545 USA. NR 13 TC 8 Z9 8 U1 2 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1505 EP 1513 DI 10.1063/1.1363664 PN 1 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800010 ER PT J AU Baker, DR Greenfield, CM DeBoo, JC Wade, MR Stallard, BW AF Baker, DR Greenfield, CM DeBoo, JC Wade, MR Stallard, BW TI Particle transport in DIII-D discharges with internal regions of enhanced confinement and counter injected neutral beams SO PHYSICS OF PLASMAS LA English DT Article ID REVERSED MAGNETIC SHEAR; ANOMALOUS TRANSPORT; D TOKAMAK; PERFORMANCE; PROFILES; PLASMAS; DRIVEN AB An analysis of experimentally measured particle transport in tokamak plasmas with negative central magnetic shear is presented. The analysis is presented in terms of a simple model for turbulent transport which allows the separation of diagonal and off diagonal terms and allows the direct comparison of particle and energy transport. Comparing the measured fluxes to the fluxes predicted by a simple quasi analytical model which specifies a relation between the diagonal and off diagonal terms allows an understanding of the reason for the difference between energy and particle fluxes. In the center of discharges with a region of enhanced confinement (or internal transport barrier), the ion thermal diffusivity becomes small and comparable to neoclassical values and the particle diffusivity also becomes small and approaches the neoclassical values. (C) 2001 American Institute of Physics. C1 Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37382 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Baker, DR (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 24 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1565 EP 1572 DI 10.1063/1.1358311 PN 1 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800019 ER PT J AU Jaeger, EF Berry, LA D'Azevedo, E Batchelor, DB Carter, MD AF Jaeger, EF Berry, LA D'Azevedo, E Batchelor, DB Carter, MD TI All-orders spectral calculation of radio-frequency heating in two-dimensional toroidal plasmas SO PHYSICS OF PLASMAS LA English DT Article ID DENSE LINEAR-SYSTEMS; ION BERNSTEIN WAVES; HOT TOKAMAK PLASMAS; ALCATOR C-MOD; CURRENT DRIVE; POLOIDAL FLOW; GLOBAL WAVES; ABSORPTION; ICRF; PROPAGATION AB Spectral calculations of radio-frequency (rf) heating in tokamak plasmas are extended to two dimensions (2-D) by taking advantage of new computational tools for distributed memory, parallel computers. The integral form of the wave equation is solved in 2-D without any assumption regarding the smallness of the ion Larmor radius (rho) relative to the perpendicular wavelength (lambda (perpendicular to)). Results are therefore applicable to all orders in k(perpendicular to)rho, where k(perpendicular to)=2 pi/lambda (perpendicular to). Previous calculations of rf wave propagation and heating in 2-D magnetized plasmas have relied on finite Larmor radius expansions (k(perpendicular to)rho <1) and are thus limited to relatively long wavelengths. In this paper, no such assumption is made, and we consider short wavelength processes such as the excitation and absorption of ion Bernstein waves in 2-D with k(perpendicular to)rho >1. Results show that this phenomenon is far more complex than simple one-dimensional plasma models would suggest. Other applications include fully self-consistent 2-D solutions for high-harmonic fast-wave heating in spherical tokamaks. These calculations require the storage and inversion of a very large, dense matrix, but numerical convergence can be improved by writing the plasma current in the laboratory frame of reference. To accurately represent the wave spectrum in this frame, the local plasma conductivity is corrected to first order in rho /L, where L is the equilibrium scale length. This correction is necessary to ensure accuracy in calculating the wave spectrum and hence the fraction of power absorbed by ions and electrons. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Jaeger, EF (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. NR 48 TC 64 Z9 64 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1573 EP 1583 DI 10.1063/1.1359516 PN 1 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800020 ER PT J AU Tikhonchuk, VT Fuchs, J Labaune, C Depierreux, S Huller, S Myatt, J Baldis, HA AF Tikhonchuk, VT Fuchs, J Labaune, C Depierreux, S Huller, S Myatt, J Baldis, HA TI Stimulated Brillouin and Raman scattering from a randomized laser beam in large inhomogeneous collisional plasmas. II. Model description and comparison with experiments SO PHYSICS OF PLASMAS LA English DT Article ID LANGMUIR DECAY INSTABILITY; RANDOM-PHASE PLATES; HOT-SPOTS; SATURATION; REFLECTIVITY; BEHAVIOR; FILAMENTS; SPECKLES AB A model for stimulated Brillouin (SBS) and Raman (SRS) backscattering of a spatially smoothed laser beam interacting with a collisional, inhomogeneous, expanding plasma is presented. It is based on the independent hot spots description [H. A. Rose and D. F. DuBois, Phys. Rev. Lett. 72, 2883 (1994)], in which the overall plasma reflectivity is assumed to be a sum of the individual speckle reflectivities. Self-focusing is taken into account in the computation of the speckle intensity profile and reflectivities. Two additions have been made to previous similar theories: (i) the thermal effects are retained along with the ponderomotive force for what concerns speckle self-focusing, and (ii) SRS (convective and absolute) is accounted for in calculations of the speckle reflectivity. The model is benchmarked against recent laser-plasma experiments at Laboratoire pour l'Utilisation des Lasers Intenses, at Ecole Polytechnique, France, with well-characterized interaction conditions. A good agreement is found between the experimental SBS levels and the model calculations using the measured plasma parameters. This agreement applies for two types of beam smoothing techniques, random phase plates, and polarization smoothing, various plasma densities, and laser energies. Self-focusing itself, and thermal effects in it, play both a fundamental role in defining the level of plasma backscattering. The absolute Raman instability in speckles dominates the SRS response. The model predictions for the SRS reflectivity are less satisfactory, although they demonstrate the same trends as the experimental data. It follows from model calculations and experimental data that the polarization smoothing technique provides an efficient method of control of parametric instabilities allowing a reduction of several times in the level of SBS and SRS reflectivities. (C) 2001 American Institute of Physics. C1 Univ Paris 06, CEA, Ecole Polytech, Lab Utilisat Lasers Intenses,CNRS,UMR 7605, F-91128 Palaiseau, France. Ecole Polytech, Ctr Phys Theor, CNRS, UMR 7644, F-91128 Palaiseau, France. Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. RP Tikhonchuk, VT (reprint author), Univ Paris 06, CEA, Ecole Polytech, Lab Utilisat Lasers Intenses,CNRS,UMR 7605, F-91128 Palaiseau, France. RI Fuchs, Julien/D-3450-2016 OI Fuchs, Julien/0000-0001-9765-0787 NR 42 TC 26 Z9 26 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1636 EP 1649 DI 10.1063/1.1357218 PN 1 PG 14 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800027 ER PT J AU Ethier, S Matte, JP AF Ethier, S Matte, JP TI Electron kinetic simulations of solid density Al plasmas produced by intense subpicosecond laser pulses. I. Ionization dynamics in 30 femtosecond pulses SO PHYSICS OF PLASMAS LA English DT Article ID FOKKER-PLANCK SIMULATIONS; INVERSE-BREMSSTRAHLUNG ABSORPTION; STEEP TEMPERATURE-GRADIENTS; X-RAY-DIFFRACTION; HEAT-TRANSPORT; DISTRIBUTIONS; MODEL; HOT; SPECTROSCOPY; EXCITATION AB The interaction of a 10(18) W/cm(2), 30 fs laser pulse with solid Al was simulated with the electron kinetic code "FPI" [J. P. Matte , Phys. Rev. Lett. 72, 1208 (1994)] in which an improved average ion module was fully coupled to the electron kinetics. It includes electron impact ionization and excitation and their inverse processes: collisional recombination and de-excitation; as well as radiative decay and pressure ionization. We compare to runs without the inverse processes, and also without atomic physics (with set to 11). Atomic physics strongly affects the energy balance and the shape of the distribution function. Line radiation is mostly due to three body recombination into excited states after the peak of the pulse, as the plasma cools down. Despite the atomic processes and the high density, strongly non-Maxwellian distribution functions were obtained due to very steep temperature gradients and strong collisional heating, at the peak of the pulse. However, after the pulse, there is a very rapid thermalization of the electron distribution to which inverse processes strongly contribute. (C) 2001 American Institute of Physics. C1 INRS Energie & Mat, Varennes, PQ J3X 1S2, Canada. RP Ethier, S (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 58 TC 14 Z9 14 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1650 EP 1658 DI 10.1063/1.1357221 PN 1 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800028 ER PT J AU Slutz, SA Douglas, MR Lash, JS Vesey, RA Chandler, GA Nash, TJ Derzon, MS AF Slutz, SA Douglas, MR Lash, JS Vesey, RA Chandler, GA Nash, TJ Derzon, MS TI Scaling and optimization of the radiation temperature in dynamic hohlraums SO PHYSICS OF PLASMAS LA English DT Article ID INERTIAL CONFINEMENT FUSION; PINCH AB A quasianalytic model of the dynamic hohlraum is presented. Results of the model are compared to both experiments and full numerical simulations with good agreement. The computational simplicity of the model allows one to find the behavior of the hohlraum radiation temperature as a function of the various parameters of the system and thus find optimum parameters as a function of the driving current. The model is used to investigate the benefits of ablative standoff and quasispherical Z pinches. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Slutz, SA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 33 Z9 33 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1673 EP 1691 DI 10.1063/1.1360213 PN 1 PG 19 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800031 ER PT J AU Glenzer, SH Berger, RL Divol, LM Kirkwood, RK MacGowan, BJ Moody, JD Langdon, AB Suter, LJ Williams, EA AF Glenzer, SH Berger, RL Divol, LM Kirkwood, RK MacGowan, BJ Moody, JD Langdon, AB Suter, LJ Williams, EA TI Reduction of stimulated scattering losses from hohlraum plasmas with laser beam smoothing SO PHYSICS OF PLASMAS LA English DT Article ID INERTIAL CONFINEMENT FUSION; BRILLOUIN-SCATTERING; PARAMETRIC-INSTABILITIES; IRRADIATED PLASMAS; RAMAN; ENERGETICS; WAVES; LIGHT AB Laser beam smoothing by spectral dispersion and by polarization smoothing has been observed to significantly reduce the scattering losses by stimulated Brillouin and stimulated Raman scattering from inertial confinement fusion hohlraums. For these measurements, the laser beam smoothing and the high-Z hohlraum wall plasma parameters approach the conditions of future inertial confinement fusion experiments. The simultaneous application of the smoothing techniques has reduced the scattering losses by almost one order of magnitude down to the 1% level. The experimental scaling of the stimulated Brillouin reflectivity compares well to modeling assuming nonlinear damping on the ion acoustic waves in three-dimensional nonlinear wave simulations and calculated hohlraum plasma conditions from radiation-hydrodynamic modeling. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. CEA, DIF, DCSA, SET, F-91680 Bruyeres Le Chatel, France. RP Glenzer, SH (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 34 TC 12 Z9 14 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1692 EP 1696 DI 10.1063/1.1363613 PN 1 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800032 ER PT J AU Mueller, D Grisham, L Kaganovich, I Watson, RL Horvat, V Zaharakis, KE Armel, MS AF Mueller, D Grisham, L Kaganovich, I Watson, RL Horvat, V Zaharakis, KE Armel, MS TI Multiple electron stripping of 3.4 MeV/amu Kr7+ and Xe11+ in nitrogen SO PHYSICS OF PLASMAS LA English DT Article ID CROSS-SECTIONS; IONIZATION; ATOMS; IONS AB Use of heavy ions beams with similar to 10 MeV/amu mass similar to 200, and average charge state of 1+ has been proposed as a driver for heavy ion fusion. Stripping of the ion beam by background gas can lead to an increase in the space charge density of the beam, which may make focusing the intense ion beam onto small targets more complex. Knowledge of the electron loss cross sections is essential to understand and address the problem. Currently, there are no 10 MeV/amu mass=200, charge state=1 beams available, and the theories that calculate electron loss cross sections can be experimentally tested only by using available beams of somewhat lower energy and higher initial charge state. The charge state distribution of ions produced in single collisions of 3.4 MeV/amu Kr7+ and 3.4 MeV/amu Xe11+ in N-2 have been measured at the Texas A&M Cyclotron Institute using a windowless gas cell. The charge states of the outgoing ions are determined by magnetic analysis using a position-sensitive microchannel-plate detector. The cross sections for single and multiple electron loss are determined, and the results indicate that substantial multiple-electron loss occurs. The relative cross section for loss of i+1 electrons is 0.3-0.7 times that for i electron loss. The average number of electrons removed per one collision (sum of the electron-weighted cross sections normalized to the total cross section) is 1.86 for Kr and 1.97 for Xe. (C) 2001 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Texas A&M Univ, Inst Cyclotron, College Stn, TX 77843 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Mueller, D (reprint author), Princeton Univ, Plasma Phys Lab, POB 453, Princeton, NJ 08543 USA. NR 17 TC 39 Z9 39 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1753 EP 1756 DI 10.1063/1.1365408 PN 1 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 423QG UT WOS:000168187800041 ER PT J AU Ryutov, DD Remington, BA Robey, HF Drake, RP AF Ryutov, DD Remington, BA Robey, HF Drake, RP TI Magnetohydrodynamic scaling: From astrophysics to the laboratory SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID SUPERNOVA HYDRODYNAMICS; INTENSE LASERS; JET EXPERIMENTS; PLASMA; CONFINEMENT; INSTABILITY; SIMULATIONS; EVOLUTION; CRITERIA; PHYSICS AB During the last few years, considerable progress has been made in simulating astrophysical phenomena in laboratory experiments with high-power lasers. Astrophysical phenomena that have drawn particular interest include supernovae explosions; young supernova remnants; galactic jets; the formation of fine structures in late supernovae remnants by instabilities; and the ablation-driven evolution of molecular clouds. A question may arise as to what extent the laser experiments, which deal with targets of a spatial scale of similar to 100 mum and occur at a time scale of a few nanoseconds, can reproduce phenomena occurring at spatial scales of a million or more kilometers and time scales from hours to many years. Quite remarkably, in a number of cases there exists a broad hydrodynamic similarity (sometimes called the "Euler similarity") that allows a direct scaling of laboratory results to astrophysical phenomena. A discussion is presented of the details of the Euler similarity related to the presence of shocks and to a special case of a strong drive. Constraints stemming from the possible development of small-scale turbulence are analyzed. The case of a gas with a spatially varying polytropic index is discussed. A possibility of scaled simulations of ablation front dynamics is one more topic covered in this paper. It is shown that, with some additional constraints, a simple similarity exists. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Michigan, Ann Arbor, MI 48105 USA. RP Ryutov, DD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI Drake, R Paul/I-9218-2012 OI Drake, R Paul/0000-0002-5450-9844 NR 58 TC 104 Z9 106 U1 4 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1804 EP 1816 DI 10.1063/1.1344562 PN 2 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500006 ER PT J AU Nazikian, R Kramer, GJ Valeo, E AF Nazikian, R Kramer, GJ Valeo, E TI A tutorial on the basic principles of microwave reflectometry applied to fluctuation measurements in fusion plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID DENSITY PROFILE MEASUREMENTS; PULSED RADAR REFLECTOMETRY; TURBULENT FLUCTUATIONS; DIII-D; TOKAMAK PLASMAS; SHEAR; MODE; CORE; CONFIGURATIONS; SENSITIVITY AB Microwave reflectometry is now routinely used for probing the structure of magnetohydrodynamic and turbulent fluctuations in fusion plasmas. Conditions specific to the core of tokamak plasmas, such as small amplitude of density irregularities and the uniformity of the background plasma, have enabled progress in the quantitative interpretation of reflectometer signals. In particular the extent of applicability of the one-dimensional (1-D) geometric optics description of the reflected field is investigated by direct comparison to 1-D full wave analysis. Significant advances in laboratory experiments are discussed which are paving the way toward a thorough understanding of this important measurement technique. Data are presented from the Tokamak Fusion Test Reactor [R. Hawryluk, Plasma Phys. Controlled Fusion 33, 1509 (1991)] identifying the validity of the geometric optics description of the scattered field and demonstrating the feasibility of imaging turbulent fluctuations in fusion scale devices. (C) 2001 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Nazikian, R (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 61 TC 79 Z9 80 U1 2 U2 13 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1840 EP 1855 DI 10.1063/1.1362534 PN 2 PG 16 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500009 ER PT J AU Hsu, SC Carter, TA Fiksel, G Ji, H Kulsrud, RM Yamada, M AF Hsu, SC Carter, TA Fiksel, G Ji, H Kulsrud, RM Yamada, M TI Experimental study of ion heating and acceleration during magnetic reconnection SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID HYBRID-DRIFT INSTABILITY; LABORATORY PLASMA; PROBE AB Ion heating and acceleration has been studied in the well-characterized reconnection layer of the Magnetic Reconnection Experiment [M. Yamada , Phys. Plasmas 4, 1936 (1997)]. Ion temperature in the layer rises substantially during null-helicity reconnection in which reconnecting field lines are anti-parallel. The plasma outflow is sub-Alfvenic due to a downstream back pressure. An ion energy balance calculation based on the data and including classical viscous heating indicates that ions are heated largely via nonclassical mechanisms. The T-i rise is much smaller during co-helicity reconnection in which field lines reconnect obliquely. This is consistent with a slower reconnection rate and a smaller resistivity enhancement over the Spitzer value. These observations show that nonclassical dissipation mechanisms can play an important role both in heating the ions and in facilitating the reconnection process. (C) 2001 American Institute of Physics. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Hsu, SC (reprint author), CALTECH, Dept Appl Phys, Pasadena, CA 91125 USA. RI Carter, Troy/E-7090-2010; Yamada, Masaaki/D-7824-2015; OI Carter, Troy/0000-0002-5741-0495; Yamada, Masaaki/0000-0003-4996-1649; Hsu, Scott/0000-0002-6737-4934 NR 33 TC 35 Z9 36 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1916 EP 1928 DI 10.1063/1.1356737 PN 2 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500018 ER PT J AU Sweet, D Ott, E Antonsen, TM Lathrop, DP Finn, JM AF Sweet, D Ott, E Antonsen, TM Lathrop, DP Finn, JM TI Blowout bifurcations and the onset of magnetic dynamo action SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID ON-OFF INTERMITTENCY; POWER SPECTRUM; RIDDLED BASINS; CHAOTIC FLOWS; TIME-SERIES; FIELD; TRANSITION; ATTRACTORS; STABILITY; SYSTEMS AB This paper numerically investigates the magnetohydrodynamic equations in three dimensions with periodic boundary conditions in a parameter range where a forced fluid flow is chaotic. It is found that the transition to dynamo action, whereby the magnetic field is sustained by interaction with the forced flow, is a blowout bifurcation. The blowout bifurcation is typified by bursting behavior, or "on-off intermittency." In particular, near the transition there are short, intermittently occurring bursts of strong magnetic field activity where the total magnetic energy is comparable to the total flow kinetic energy. Between these bursts the magnetic energy is very small. As one approaches the transition from the dynamo-active side, the time between bursts becomes longer and longer, approaching infinity at the transition. Numerical verification is given for the presence of signature scaling laws in numerical computations utilizing a pseudospectral model with triply periodic boundary conditions. This work implies specific testable predictions for experimental dynamos. (C) 2001 American Institute of Physics. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Univ Maryland, Dept Elect Engn, College Pk, MD 20742 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Sweet, D (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. RI O, E/F-1630-2015; Antonsen, Thomas/D-8791-2017 OI Antonsen, Thomas/0000-0002-2362-2430 NR 40 TC 16 Z9 16 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1944 EP 1952 DI 10.1063/1.1342228 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500021 ER PT J AU Kaye, SM Bell, MG Bell, RE Bialek, J Bigelow, T Bitter, M Bonoli, P Darrow, D Efthimion, P Ferron, J Fredrickson, E Gates, D Grisham, L Hosea, J Johnson, D Kaita, R Kubota, S Kugel, H LeBlanc, B Maingi, R Manickam, J Mau, TK Maqueda, RJ Mazzucato, E Menard, J Mueller, D Nelson, B Nishino, N Ono, M Paoletti, F Paul, S Peng, YKM Phillips, CK Raman, R Ryan, P Sabbagh, SA Schaffer, M Skinner, CH Stutman, D Swain, D Synakowski, E Takase, Y Wilgen, J Wilson, JR Zhu, W Zweben, S Bers, A Carter, M Deng, B Domier, C Doyle, E Finkenthal, M Hill, K Jarboe, T Jardin, S Ji, H Lao, L Lee, KC Luhmann, N Majeski, R Medley, S Park, H Peebles, T Pinsker, RI Porter, G Ram, A Rensink, M Rognlien, T Stotler, D Stratton, B Taylor, G Wampler, W Wurden, GA Xu, XQ Zeng, L AF Kaye, SM Bell, MG Bell, RE Bialek, J Bigelow, T Bitter, M Bonoli, P Darrow, D Efthimion, P Ferron, J Fredrickson, E Gates, D Grisham, L Hosea, J Johnson, D Kaita, R Kubota, S Kugel, H LeBlanc, B Maingi, R Manickam, J Mau, TK Maqueda, RJ Mazzucato, E Menard, J Mueller, D Nelson, B Nishino, N Ono, M Paoletti, F Paul, S Peng, YKM Phillips, CK Raman, R Ryan, P Sabbagh, SA Schaffer, M Skinner, CH Stutman, D Swain, D Synakowski, E Takase, Y Wilgen, J Wilson, JR Zhu, W Zweben, S Bers, A Carter, M Deng, B Domier, C Doyle, E Finkenthal, M Hill, K Jarboe, T Jardin, S Ji, H Lao, L Lee, KC Luhmann, N Majeski, R Medley, S Park, H Peebles, T Pinsker, RI Porter, G Ram, A Rensink, M Rognlien, T Stotler, D Stratton, B Taylor, G Wampler, W Wurden, GA Xu, XQ Zeng, L CA NSTX Team TI Initial physics results from the National Spherical Torus Experiment SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID TOKAMAK; PLASMAS; LIMITS; START AB The mission of the National Spherical Torus Experiment (NSTX) is to extend the understanding of toroidal physics to low aspect ratio (R/a similar or equal to1.25) in low collisionality regimes. NSTX is designed to operate with up to 6 MW of high harmonic fast wave (HHFW) heating and current drive, 5 MW of neutral beam injection (NBI) and co-axial helicity injection (CHI) for noninductive startup. Initial experiments focused on establishing conditions that will allow NSTX to achieve its aims of simultaneous high beta (t) and high-bootstrap current fraction, and to develop methods for noninductive operation, which will be necessary for Spherical Torus power plants. Ohmic discharges with plasma currents up to 1 MA and with a range of shapes and configurations were produced. Density limits in deuterium and helium reached 80% and 120% of the Greenwald limit, respectively. Significant electron heating was observed with up to 2.3 MW of HHFW. Up to 270 kA of toroidal current for up to 200 ms was produced noninductively using CHI. Initial NBI experiments were carried out with up to two beam sources (3.2 MW). Plasmas with stored energies of up to 140 kJ and beta (t)=21% were produced. (C) 2001 American Institute of Physics. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Columbia Univ, Dept Appl Phys, New York, NY 10027 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. MIT, Cambridge, MA 02139 USA. Gen Atom Co, San Diego, CA 92186 USA. Univ Calif Los Angeles, Los Angeles, CA USA. Univ Calif San Diego, San Diego, CA 92103 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Washington, Seattle, WA 98105 USA. Hiroshima Univ, Hiroshima, Japan. Johns Hopkins Univ, Baltimore, MD USA. Univ Tokyo, Tokyo, Japan. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Sandia Natl Lab, Santa Fe, NM USA. RP Kaye, SM (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Jardin, Stephen/E-9392-2010; Sabbagh, Steven/C-7142-2011; Nishino, Nobuhiro/D-6390-2011; Stotler, Daren/J-9494-2015; Stutman, Dan/P-4048-2015; Wurden, Glen/A-1921-2017; OI Stotler, Daren/0000-0001-5521-8718; Wurden, Glen/0000-0003-2991-1484; Menard, Jonathan/0000-0003-1292-3286 NR 33 TC 44 Z9 44 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 1977 EP 1987 DI 10.1063/1.1343089 PN 2 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500025 ER PT J AU Osborne, TH Leonard, AW Mahdavi, MA Chu, M Fenstermacher, ME La Haye, R McKee, G Petrie, TW Doyle, E Staebler, G Wade, MR AF Osborne, TH Leonard, AW Mahdavi, MA Chu, M Fenstermacher, ME La Haye, R McKee, G Petrie, TW Doyle, E Staebler, G Wade, MR CA DIII-D Team TI Gas puff fueled H-mode discharges with good energy confinement above the Greenwald density limit on DIII-D SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID FLUCTUATION MEASUREMENTS; TRANSPORT; TOKAMAKS; STABILITY; PEDESTAL; REGIMES AB ELMing (edge-localized) H-mode discharges with densities as high as 40% above the Greenwald density and good energy confinement, HITER-89P=2, were obtained with D-2 gas puffing on DIII-D [Chan , Proceedings of the 16th IAEA Conference, Montreal (International Atomic Energy Agency, Vienna, 1996), Vol. 1, p. 95]. These discharges have performance comparable to the best pellet fueled DIII-D discharges. Spontaneous peaking of the density profile was an important factor in obtaining high energy confinement. Without density profile peaking, the energy confinement at high density degraded with reduction in the H-mode pedestal pressure under the stiff temperature profile conditions observed at high density on DIII-D. Reduction in the pedestal pressure was associated with loss of access to the second stable regime for ideal ballooning modes at the edge, and change in the edge-localized mode (ELM) instability from a low to high toroidal mode number. Gyrokinetic stability calculations indicate that the core of the high-density discharges is dominated by ion temperature gradient mode turbulence. A turbulent transport simulation with the GLF23 [Waltz , Phys. Plasmas 4, 2482 (1997)] code produced stiff temperature profiles in agreement with the experiment and did not indicate the formation of an internal transport barrier. Helium transport studies showed an anomalous inward particle pinch at high density. The highest density discharges were terminated by onset of a magnetohydromagnetic instability, which is consistent with destabilization of neoclassical tearing modes through peaking of the pressure profile. (C) 2001 American Institute of Physics. C1 Gen Atom Co, San Diego, CA 92138 USA. Univ Calif Lawrence Livermore Natl Lab, Div Energy, Magnet Fus Energy Program, Livermore, CA 94550 USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Calif Los Angeles, EE Dept, Los Angeles, CA 90024 USA. Lockheed Martin Energy Res Corp, Oak Ridge Natl Lab, Fus Energy Div, Oak Ridge, TN 37831 USA. RP Osborne, TH (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92138 USA. NR 33 TC 22 Z9 22 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2017 EP 2022 DI 10.1063/1.1345504 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500030 ER PT J AU Fiore, CL Rice, JE Bonoli, PT Boivin, RL Goetz, JA Hubbard, AE Hutchinson, IH Granetz, RS Greenwald, MJ Marmar, ES Mossessian, D Porkolab, M Taylor, G Snipes, J Wolfe, SM Wukitch, SJ AF Fiore, CL Rice, JE Bonoli, PT Boivin, RL Goetz, JA Hubbard, AE Hutchinson, IH Granetz, RS Greenwald, MJ Marmar, ES Mossessian, D Porkolab, M Taylor, G Snipes, J Wolfe, SM Wukitch, SJ TI Internal transport barriers on alcator C-Mod SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID REVERSED MAGNETIC SHEAR; H-MODE; CONFINEMENT; DISCHARGES; TOKAMAK; PLASMAS; ROTATION; PROFILE AB The formation of internal transport barriers (ITBs) has been observed in the core region of Alcator C-Mod [I. H. Hutchinson , Phys. Plasmas 1, 1511 (1994)] under a variety of conditions. The improvement in core confinement following pellet injection (pellet enhanced performance or PEP mode) has been well documented on Alcator C-Mod in the past. Recently three new ITB phenomena have been observed which require no externally applied particle or momentum input. Short lived ITBs form spontaneously following the high confinement to low confinement mode transition and are characterized by a large increase in the global neutron production (enhanced neutron or EN modes). Experiments with ion cyclotron range of frequencies power injection to the plasma off-axis on the high field side results in the central density rising abruptly and becoming peaked. The ITB formed at this time lasts for ten energy confinement times. The central toroidal rotation velocity decreases and changes sign as the density rises. Similar spontaneous ITBs have been observed in ohmically heated H-mode plasmas. All of these ITB events have strongly peaked density profiles with a minimum in the density scale length occurring near r/a=0.5 and have improved confinement parameters in the core region of the plasma. (C) 2001 American Institute of Physics. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Fiore, CL (reprint author), MIT, Plasma Sci & Fus Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Hutchinson, Ian/D-1136-2009; OI Hutchinson, Ian/0000-0003-4276-6576; Greenwald, Martin/0000-0002-4438-729X NR 28 TC 34 Z9 34 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2023 EP 2028 DI 10.1063/1.1345883 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500031 ER PT J AU Hubbard, AE Boivin, RL Granetz, RS Greenwald, M Hughes, JW Hutchinson, IH Irby, J LaBombard, B Lin, Y Marmar, ES Mazurenko, A Mossessian, D Nelson-Melby, E Porkolab, M Snipes, JA Terry, J Wolfe, S Wukitch, S Carreras, BA Klein, V Pedersen, TS AF Hubbard, AE Boivin, RL Granetz, RS Greenwald, M Hughes, JW Hutchinson, IH Irby, J LaBombard, B Lin, Y Marmar, ES Mazurenko, A Mossessian, D Nelson-Melby, E Porkolab, M Snipes, JA Terry, J Wolfe, S Wukitch, S Carreras, BA Klein, V Pedersen, TS TI Pedestal profiles and fluctuations in C-Mod enhanced D-alpha H-modes SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID CONFINEMENT MODES; EDGE PEDESTAL; DIII-D; ALCATOR; TOKAMAK; PLASMAS; PARAMETERS; TRANSPORT; UPGRADE; REGION AB High resolution measurements on the Alcator C-Mod tokamak [I. H. Hutchinson , Phys. Plasmas 1, 1551 (1994)] of the transport barrier in the "Enhanced D-alpha" (EDA) regime, which has increased particle transport without large edge localized modes, show steep density and temperature gradients over a region of 2-5 mm, with peak pressure gradients up to 12 MPa/m. Evolution of the pedestal at the L-H transition is consistent with a large, rapid drop in thermal conductivity across the barrier. A quasi-coherent fluctuation in density, potential, and B-pol, with f(0)similar to 50-150 kHz and k(theta)similar to4 cm(-1), always appears in the barrier during EDA, and drives a large particle flux. Conditions to access the steady-state EDA regime in deuterium include delta >0.35, q(95)>3.5, and L-mode target density (n) over bar (e)>1.2x10(20) m(-3). A reduced q(95) limit is found for hydrogen discharges. (C) 2001 American Institute of Physics. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ New Mexico, Albuquerque, NM 87106 USA. Columbia Univ, New York, NY 10027 USA. RP Hubbard, AE (reprint author), MIT, Plasma Sci & Fus Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Lin, Yijun/B-5711-2009; Hutchinson, Ian/D-1136-2009; OI Hutchinson, Ian/0000-0003-4276-6576; Greenwald, Martin/0000-0002-4438-729X NR 40 TC 64 Z9 64 U1 2 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2033 EP 2040 DI 10.1063/1.1348329 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500033 ER PT J AU Okabayashi, M Bialek, J Chance, MS Chu, MS Fredrickson, ED Garofalo, AM Gryaznevich, M Hatcher, RE Jensen, TH Johnson, LC La Haye, RJ Lazarus, EA Makowski, MA Manickam, J Navratil, GA Scoville, JT Strait, EJ Turnbull, AD Walker, ML AF Okabayashi, M Bialek, J Chance, MS Chu, MS Fredrickson, ED Garofalo, AM Gryaznevich, M Hatcher, RE Jensen, TH Johnson, LC La Haye, RJ Lazarus, EA Makowski, MA Manickam, J Navratil, GA Scoville, JT Strait, EJ Turnbull, AD Walker, ML CA DIII-D Team TI Active feedback stabilization of the resistive wall mode on the DIII-D device SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID HIGH-BETA; PLASMA ROTATION; MAGNETOHYDRODYNAMIC INSTABILITIES; ADVANCED TOKAMAK; EXTERNAL-MODES; SHELL; STABILITY; SHEAR; KINK AB A proof of principle magnetic feedback stabilization experiment has been carried out to suppress the resistive wall mode (RWM), a branch of the ideal magnetohydrodynamic (MHD) kink mode under the influence of a stabilizing resistive wall, on the DIII-D tokamak device [Plasma Phys. Controlled Fusion Research (International Atomic Energy Agency, Vienna, 1986), p. 159; Phys. Plasmas 1, 1415 (1994)]. The RWM was successfully suppressed and the high beta duration above the no-wall limit was extended to more than 50 times the resistive wall flux diffusion time. It was observed that the mode structure was well preserved during the time of the feedback application. Several lumped parameter formulations were used to study the feedback process. The observed feedback characteristics are in good qualitative agreement with the analysis. These results provide encouragement to future efforts towards optimizing the RWM feedback methodology in parallel to what has been successfully developed for the n=0 vertical positional control. Newly developed MHD codes have been extremely useful in guiding the experiments and in providing possible paths for the next step. (C) 2001 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Okabayashi, M (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. OI Walker, Michael/0000-0002-4341-994X NR 36 TC 99 Z9 100 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2071 EP 2082 DI 10.1063/1.1351823 PN 2 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500038 ER PT J AU Reiman, A Ku, L Monticello, D Hirshman, S Hudson, S Kessel, C Lazarus, E Mikkelsen, D Zarnstorff, M Berry, LA Boozer, A Brooks, A Cooper, WA Drevlak, M Fredrickson, E Fu, G Goldston, R Hatcher, R Isaev, M Jun, C Knowlton, S Lewandowski, J Lin, Z Lyon, JF Merkel, P Mikhailov, M Miner, W Mynick, H Neilson, G Nelson, BE Nuhrenberg, C Pomphrey, N Redi, M Reiersen, W Rutherford, P Sanchez, R Schmidt, J Spong, D Strickler, D Subbotin, A Valanju, P White, R AF Reiman, A Ku, L Monticello, D Hirshman, S Hudson, S Kessel, C Lazarus, E Mikkelsen, D Zarnstorff, M Berry, LA Boozer, A Brooks, A Cooper, WA Drevlak, M Fredrickson, E Fu, G Goldston, R Hatcher, R Isaev, M Jun, C Knowlton, S Lewandowski, J Lin, Z Lyon, JF Merkel, P Mikhailov, M Miner, W Mynick, H Neilson, G Nelson, BE Nuhrenberg, C Pomphrey, N Redi, M Reiersen, W Rutherford, P Sanchez, R Schmidt, J Spong, D Strickler, D Subbotin, A Valanju, P White, R TI Recent advances in the design of quasiaxisymmetric stellarator plasma configurations SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID ENERGETIC PARTICLE-TRANSPORT; NEOCLASSICAL TRANSPORT; STABILITY; TOKAMAK; MAGNETOHYDRODYNAMICS; SYMMETRY; ISLANDS AB Strategies for the improvement of quasiaxisymmetric stellarator configurations are explored. Calculations of equilibrium flux surfaces for candidate configurations are also presented. One optimization strategy is found to generate configurations with improved neoclassical confinement, simpler coils with lower current density, and improved flux surface quality relative to previous designs. The flux surface calculations find significant differences in the extent of islands and stochastic regions between candidate configurations. (These calculations do not incorporate the predicted beneficial effects of perturbed bootstrap currents.) A method is demonstrated for removing low order islands from candidate configurations by relatively small modifications of the configuration. One configuration is identified as having particularly desirable properties for a proposed experiment. (C) 2001 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. CRPP PPB, CH-1015 Lausanne, Switzerland. EURATOM, IPP, D-17491 Greifswald, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Columbia Univ, Dept Appl Phys, New York, NY 10027 USA. Univ Texas, Austin, TX 78712 USA. Kurchatov Inst, Moscow, Russia. Univ Carlos III Madrid, Madrid, Spain. Auburn Univ, Dept Phys, Auburn, AL 36849 USA. RP Reiman, A (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. EM reiman@pppl.gov RI Sanchez, Raul/C-2328-2008; pomphrey, neil/G-4405-2010; Spong, Donald/C-6887-2012; Hudson, Stuart/H-7186-2013; White, Roscoe/D-1773-2013; Isaev, Maxim/A-7910-2012 OI Spong, Donald/0000-0003-2370-1873; Hudson, Stuart/0000-0003-1530-2733; White, Roscoe/0000-0002-4239-2685; Isaev, Maxim/0000-0002-8492-0650 NR 36 TC 39 Z9 39 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2083 EP 2094 DI 10.1063/1.1351826 PN 2 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500039 ER PT J AU LaBombard, B Boivin, RL Greenwald, M Hughes, J Lipschultz, B Mossessian, D Pitcher, CS Terry, JL Zweben, SJ AF LaBombard, B Boivin, RL Greenwald, M Hughes, J Lipschultz, B Mossessian, D Pitcher, CS Terry, JL Zweben, SJ CA Alacator Grp TI Particle transport in the scrape-off layer and its relationship to discharge density limit in Alcator C-Mod SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID EDGE PLASMAS; DIVERTOR; JET AB Cross-field particle transport in the scrape-off layer (SOL) of Alcator C-Mod [Phys. Plasmas 1, 1511 (1994)] can be characterized by an effective particle diffusivity (D-eff) that increases markedly with distance from the separatrix. As a consequence, recycling onto the main-chamber walls is large compared to plasma flows into the divertor volume. The SOL exhibits a two-layer structure: Steep gradients and moderate fluctuation levels are typically found in a similar to5 mm region near the separatrix (near SOL) where parallel electron conduction typically dominates energy losses. Small gradients and larger fluctuation levels with longer correlation times are found outside this region (far SOL). D-eff in the near SOL increases strongly with local plasma collisionality normalized to the magnetic connection length. As the discharge density limit is approached, D-eff and associated fluctuation levels become large across the entire SOL and cross-field heat convection everywhere exceeds parallel conduction losses, impacting the power balance of the discharge. (C) 2001 American Institute of Physics. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP LaBombard, B (reprint author), MIT, Plasma Sci & Fus Ctr, 175 Albany St, Cambridge, MA 02139 USA. RI Lipschultz, Bruce/J-7726-2012; OI Lipschultz, Bruce/0000-0001-5968-3684; Greenwald, Martin/0000-0002-4438-729X NR 32 TC 126 Z9 127 U1 2 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2107 EP 2117 DI 10.1063/1.1352596 PN 2 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500042 ER PT J AU Schaffer, MJ Bray, BD Boedo, JA Carlstrom, TN Colchin, RJ Hsieh, CL Moyer, RA Porter, GD Rognlien, TD Watkins, JG AF Schaffer, MJ Bray, BD Boedo, JA Carlstrom, TN Colchin, RJ Hsieh, CL Moyer, RA Porter, GD Rognlien, TD Watkins, JG CA DIII-D Team TI ExB circulation at the tokamak divertor X point SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID DIII-D TOKAMAK; ELECTRIC-FIELD; SEPARATRIX; PLASMA; OPERATION; PROBE AB Detailed measurements in two dimensions by probes and Thomson scattering reveal unexpected local electric potential and electron pressure (p(e)) maxima near the divertor X point in L-mode plasmas in the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)]. The potential drives ExB circulation about the X point, thereby exchanging plasma between closed and open magnetic surfaces at rates that can be comparable to the total cross-separatrix transport. The potential is consistent with the classical parallel Ohm's law. A simple model is proposed to explain the pressure and potential hills in low power, nearly detached plasmas. Recent two-dimensional edge transport modeling with plasma drifts also shows X-point pressure and potential hills but by a different mechanism. These experimental and theoretical results demonstrate that low power tokamak plasmas can be far from poloidal uniformity in a boundary layer just inside the separatrix. Additional data, although preliminary and incomplete, suggest that ExB circulation across the separatrix might be a common feature of low confinement behavior. (C) 2001 American Institute of Physics. C1 Univ Calif San Diego, San Diego, CA 92103 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Sandia Natl Labs, Albuquerque, NM USA. RP Schaffer, MJ (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 24 TC 18 Z9 18 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2118 EP 2124 DI 10.1063/1.1352597 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500043 ER PT J AU Burrell, KH Austin, ME Brennan, DP DeBoo, JC Doyle, EJ Fenzi, C Fuchs, C Gohil, P Greenfield, CM Groebner, RJ Lao, LL Luce, TC Makowski, MA McKee, GR Moyer, RA Petty, CC Porkolab, M Rettig, CL Rhodes, TL Rost, JC Stallard, BW Strait, EJ Synakowski, EJ Wade, MR Watkins, JG West, WP AF Burrell, KH Austin, ME Brennan, DP DeBoo, JC Doyle, EJ Fenzi, C Fuchs, C Gohil, P Greenfield, CM Groebner, RJ Lao, LL Luce, TC Makowski, MA McKee, GR Moyer, RA Petty, CC Porkolab, M Rettig, CL Rhodes, TL Rost, JC Stallard, BW Strait, EJ Synakowski, EJ Wade, MR Watkins, JG West, WP TI Quiescent double barrier high-confinement mode plasmas in the DIII-D tokamak SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID TURBULENCE; TRANSPORT; SYSTEM; PROBE AB High-confinement (H-mode) operation is the choice for next-step tokamak devices based either on conventional or advanced tokamak physics. This choice, however, comes at a significant cost for both the conventional and advanced tokamaks because of the effects of edge localized modes (ELMs). ELMs can produce significant erosion in the divertor and can affect the beta limit and reduced core transport regions needed for advanced tokamak operation. Experimental results from DIII-D [J. L. Luxon , Plasma Physics and Controlled Nuclear Fusion Research 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] this year have demonstrated a new operating regime, the quiescent H-mode regime, which solves these problems. We have achieved quiescent H-mode operation that is ELM-free and yet has good density and impurity control. In addition, we have demonstrated that an internal transport barrier can be produced and maintained inside the H-mode edge barrier for long periods of time (>3.5 s or > 25 energy confinement times tau (E)), yielding a quiescent double barrier regime. By slowly ramping the input power, we have achieved beta H-N(89)=7 for up to 5 times the tau (E) of 150 ms. The beta H-N(89) values of 7 substantially exceed the value of 4 routinely achieved in the standard ELMing H mode. The key factors in creating the quiescent H-mode operation are neutral beam injection in the direction opposite to the plasma current (counter injection) plus cryopumping to reduce the density. Density and impurity control in the quiescent H mode is possible because of the presence of an edge magnetohydrodynamic (MHD) oscillation, the edge harmonic oscillation, which enhances the edge particle transport while leaving the energy transport unaffected. (C) 2001 American Institute of Physics. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Texas, Austin, TX 78712 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Wisconsin, Madison, WI 53706 USA. Max Planck Inst Plasmaphys, Garching, Germany. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Calif San Diego, San Diego, CA 92103 USA. MIT, Cambridge, MA 02139 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Burrell, KH (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 26 TC 122 Z9 122 U1 3 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2153 EP 2162 DI 10.1063/1.1355981 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500048 ER PT J AU Perkins, FW White, RB Bonoli, PT Chan, VS AF Perkins, FW White, RB Bonoli, PT Chan, VS TI Generation of plasma rotation in a tokamak by ion-cyclotron absorption of fast Alfven waves SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID ALCATOR C-MOD; IMPURITY TOROIDAL ROTATION; OHMIC H-MODE; TRANSPORT; ICRF; TURBULENCE; SHEAR; STABILIZATION; CONFINEMENT; MOMENTUM AB A mechanism is proposed and evaluated for driving rotation in tokamak plasmas by minority ion-cyclotron heating, even though this heating introduces negligible angular momentum. The mechanism has two elements: First, angular momentum transport is governed by a diffusion equation with a boundary condition at the separatrix. Second, Monte Carlo calculations show that ion-cyclotron energized particles will provide a torque density source which has a zero volume integral but separated positive and negative regions. With such a source, a solution of the diffusion equation predicts that ion-cyclotron heating will cause a rotational shear layer to develop. The corresponding jump in plasma rotation Delta Omega is found to be negative outwards when the ion-cyclotron surface lies on the low-field side of the magnetic axis and positive outwards with the resonance on the high-field side. The magnitude of the jump Delta Omega=(4q(max)WJ(2)*) (eBR(3)a(2)n(e)(2 pi)(2))(-1)(tau (M)/tau (E)) where \J(2)*\approximate to2-4 is a nondimensional rotation frequency calculated by the Monte Carlo ORBIT code [R. B. White and M. S. Chance, Phys. Fluids 27, 2455 (1984)]. For a no-slip boundary condition when the resonance lies on the low-field side of the magnetic axis, the sense of predicted axial rotation is co-current and overall agreement with experiment is good. When the resonance lies on the high-field side, the predicted rotation becomes countercurrent for a no-slip boundary while the observed rotation remains co-current. The rotational shear layer position is controllable and of sufficient magnitude to affect microinstabilities. (C) 2001 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Gen Atom Co, San Diego, CA 92186 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. RP Perkins, FW (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 26 TC 41 Z9 42 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2181 EP 2187 DI 10.1063/1.1362535 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500051 ER PT J AU Ongena, J Budny, R Dumortier, P Jackson, GL Kubo, H Messiaen, AM Murakami, M Strachan, JD Sydora, R Tokar, M Unterberg, B Samm, U Vandenplas, PE Weynants, R Asakura, N Brix, M Charlet, M Coffey I Cordey, G Erents, SK Fuchs, G von Hellermann, M Hillis, DL Hogan, J Horton, LD Ingesson, LC Itami, K Jachmich, S Kallenbach, A Koslowski, HR Kraemer-Flecken, A Lawson, KD Loarte, A Maddison, GP Mank, G McKee, GR Meigs, A Milani, F Monier-Garbet, P Nave, MFF Puiatti, ME Parail V Rapp, J Sakurai, S Sharapov, S Sartori, F Stamp, M Tamai, H Telesca, G Valisa, M Van Wassenhove, G Weyssow, B Zastrow, KD AF Ongena, J Budny, R Dumortier, P Jackson, GL Kubo, H Messiaen, AM Murakami, M Strachan, JD Sydora, R Tokar, M Unterberg, B Samm, U Vandenplas, PE Weynants, R Asakura, N Brix, M Charlet, M Coffey, I Cordey, G Erents, SK Fuchs, G von Hellermann, M Hillis, DL Hogan, J Horton, LD Ingesson, LC Itami, K Jachmich, S Kallenbach, A Koslowski, HR Kraemer-Flecken, A Lawson, KD Loarte, A Maddison, GP Mank, G McKee, GR Meigs, A Milani, F Monier-Garbet, P Nave, MFF Puiatti, ME Parail, V Rapp, J Sakurai, S Sharapov, S Sartori, F Stamp, M Tamai, H Telesca, G Valisa, M Van Wassenhove, G Weyssow, B Zastrow, KD CA EFDA-JET Workprogramme Contributors TI Recent progress toward high performance above the Greenwald density limit in impurity seeded discharges in limiter and divertor tokamaks SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID HIGH CONFINEMENT; IMPROVED MODE; TRANSPORT; TEXTOR-94; RADIATION; PLASMAS; TRANSITION; TURBULENCE; INJECTION AB An overview is given of recent advances toward the realization of high density, high confinement plasmas with radiating mantles in limiter and divertor tokamaks worldwide. Radiatively improved mode discharges on the Torus Experiment for Technology Oriented Research 94 (TEXTOR-94) [Proceedings of the 16th IEEE Symposium on Fusion Engineering, 1995 (Institute for Electrical and Electronics Engineers, Piscataway, NJ, 1995), p. 470] have recently been obtained at trans-Greenwald densities (up to (n) over bar /n(GW)=1.4) with high confinement mode free of edge localized modes (ELM-free H-mode) confinement quality. Experiments in DIII-D [J. Luxon, Proceedings of the 11th IAEA Conference on Plasma Physics and Controlled Nuclear Fusion Research (International Atomic Energy Association, Vienna, 1987), Vol. 1, p. 159] divertor plasmas with a low confinement mode edge have confirmed the dramatic changes in confinement observed with impurity seeding on TEXTOR-94. Recent experiment with impurity seeding on the Joint European Torus [Rebut , Fusion Eng. Des. 22, 7 (1993)], and the Japanese Atomic Energy Research Institute Tokamak 60 Upgrade [Horiike , Fusion Eng. Des. 16, 285 (1991); Hosogane , Proceedings of the 16th IAEA Conference on Plasma Physics and Controlled Nuclear Fusion Research Montreal, 1987 (International Atomic Energy Association, Vienna, 1987), Vol. 3, p. 555] have extended high confinement in ELMy H-mode plasmas to higher densities. Finally, recent progress in the physical understanding of radiating mantle plasmas is summarized. (C) 2001 American Institute of Physics. C1 Assoc EURATOM Belgian State, LPP, ERM KMS, B-1000 Brussels, Belgium. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. DIII D Natl Fus Facil, San Diego, CA 92186 USA. Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 3110913, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Alberta, Edmonton, AB, Canada. Forschungszentrum Julich, IPP, EURATOM Assoc, D-52425 Julich, Germany. UKAEA Euratom Fus Assoc, Culham, England. EURATOM, FOM IVP, NL-3430 BE Nieuwegein, Netherlands. Max Planck Inst Plasma Phys, EURATOM Assoc, D-85748 Garching, Germany. EFDA CSU, D-85748 Garching, Germany. Univ Wisconsin, Madison, WI USA. CEA Cadarache, F-13108 St Paul Les Durance, France. EURATOM IST Assoc, CFN, P-1096 Lisbon, Portugal. Consorzio RFX, I-35127 Padua, Italy. Free Univ Brussels, Assoc EURATOM Belgian State, B-1050 Brussels, Belgium. RP Ongena, J (reprint author), Assoc EURATOM Belgian State, LPP, ERM KMS, B-1000 Brussels, Belgium. RI Nave, Maria/A-5581-2013; OI Nave, Maria/0000-0003-2078-6584; sartori, Filippo/0000-0002-3451-3467; Rapp, Juergen/0000-0003-2785-9280; Tokar, Mikhail/0000-0002-9536-9841; Koslowski, Hans Rudolf/0000-0002-1571-6269; Kramer-Flecken, Andreas/0000-0003-4146-5085; Unterberg, Bernhard/0000-0003-0866-957X NR 41 TC 45 Z9 47 U1 0 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2188 EP 2198 DI 10.1063/1.1364513 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500052 ER PT J AU Wade, MR Luce, TC Politzer, PA Ferron, JR Allen, SL Austin, ME Baker, DR Bray, B Brennen, DP Burrell, KH Casper, TA Chu, MS DeBoo, JC Doyle, EJ Garofalo, AM Gohil, P Gorelov, IA Greenfield, CM Groebner, RJ Heidbrink, WW Hsieh, CL Hyatt, AW Jayakumar, R Kinsey, JE La Haye, RJ Lao, LL Lasnier, CJ Lazarus, EA Leonard, AW Lin-Liu, YR Lohr, J Mahdavi, MA Makowski, MA Murakami, M Petty, CC Pinsker, RI Prater, R Rettig, CL Rhodes, TL Rice, BW Strait, EJ Taylor, TS Thomas, DM Turnbull, AD Watkins, JG West, WP Wong, KL AF Wade, MR Luce, TC Politzer, PA Ferron, JR Allen, SL Austin, ME Baker, DR Bray, B Brennen, DP Burrell, KH Casper, TA Chu, MS DeBoo, JC Doyle, EJ Garofalo, AM Gohil, P Gorelov, IA Greenfield, CM Groebner, RJ Heidbrink, WW Hsieh, CL Hyatt, AW Jayakumar, R Kinsey, JE La Haye, RJ Lao, LL Lasnier, CJ Lazarus, EA Leonard, AW Lin-Liu, YR Lohr, J Mahdavi, MA Makowski, MA Murakami, M Petty, CC Pinsker, RI Prater, R Rettig, CL Rhodes, TL Rice, BW Strait, EJ Taylor, TS Thomas, DM Turnbull, AD Watkins, JG West, WP Wong, KL TI Progress toward long-pulse high-performance Advanced Tokamak discharges on the DIII-D tokamak SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID MAGNETIC SHEAR; ENHANCED CONFINEMENT; HIGH-BETA; PLASMAS; MODE; STABILIZATION; TRANSPORT; STABILITY; OPTIMIZATION; TURBULENCE AB Significant progress has been made in obtaining high-performance discharges for many energy confinement times in the DIII-D tokamak [J. L. Luxon , Plasma Physics and Controlled Fusion Research (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159]. Normalized performance (measured by the product of beta H-N(89) and indicative of the proximity to both conventional beta limits and energy confinement quality, respectively) similar to 10 has been sustained for >5 tau (E) with q(min)>1.5. These edge localized modes (ELMing) H-mode discharges have beta similar to5%, which is limited by the onset of resistive wall modes slightly above the ideal no-wall n=1 limit, with approximately 75% of the current driven noninductively. The remaining Ohmic current is localized near the half-radius. The DIII-D electron cyclotron heating system is being upgraded to replace this inductively driven current with localized electron cyclotron current drive (ECCD). Density control, which is required for effective ECCD, has been successfully demonstrated in long-pulse high-performance ELMing H-mode discharges with beta (N)H(89)similar to7 for up to 6.3 s. In plasma shapes compatible with good density control in the present divertor configuration, the achieved beta (N) is somewhat less than that in the high beta H-N(89)=10 discharges. (C) 2001 American Institute of Physics. C1 Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Texas, Austin, TX 78712 USA. ORISE, Oak Ridge, TN 37831 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Columbia Univ, New York, NY 10027 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif Irvine, Irvine, CA USA. Lehigh Univ, Bethlehem, PA 18015 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wade, MR (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 34 TC 45 Z9 45 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2208 EP 2216 DI 10.1063/1.1355980 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500054 ER PT J AU Munro, DH Celliers, PM Collins, GW Gold, DM Da Silva, LB Haan, SW Cauble, RC Hammel, BA Hsing, WW AF Munro, DH Celliers, PM Collins, GW Gold, DM Da Silva, LB Haan, SW Cauble, RC Hammel, BA Hsing, WW TI Shock timing technique for the National Ignition Facility SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID INTERFEROMETER AB Among the final shots at the Nova laser [Campbell , Rev. Sci. Instrum. 57, 2101 (1986)] was a series testing the VISAR (velocity interferometry system for any reflector) technique that will be the primary diagnostic for timing the shocks in a NIF (National Ignition Facility) ignition capsule. At Nova, the VISAR technique worked over the range of shock strengths and with the precision required for the NIF shock timing job-shock velocities in liquid D-2 from 12 to 65 mum/ns with better than 2% accuracy. VISAR images showed stronger shocks overtaking weaker ones, which is the basis of the plan for setting the pulse shape for the NIF ignition campaign. The technique is so precise that VISAR measurements may also play a role in certifying beam-to-beam and shot-to-shot repeatability of NIF laser pulses. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Munro, DH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 9 TC 68 Z9 74 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2245 EP 2250 DI 10.1063/1.1347037 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500059 ER PT J AU Meyerhofer, DD Delettrez, JA Epstein, R Glebov, VY Goncharov, VN Keck, RL McCrory, RL McKenty, PW Marshall, FJ Radha, PB Regan, SP Roberts, S Seka, W Skupsky, S Smalyuk, VA Sorce, C Stoeckl, C Soures, JM Town, RPJ Yaakobi, B Zuegel, JD Frenje, J Li, CK Petrasso, RD Seguin, FH Fletcher, K Padalino, S Freeman, C Izumi, N Lerche, R Phillips, TW Sangster, TC AF Meyerhofer, DD Delettrez, JA Epstein, R Glebov, VY Goncharov, VN Keck, RL McCrory, RL McKenty, PW Marshall, FJ Radha, PB Regan, SP Roberts, S Seka, W Skupsky, S Smalyuk, VA Sorce, C Stoeckl, C Soures, JM Town, RPJ Yaakobi, B Zuegel, JD Frenje, J Li, CK Petrasso, RD Seguin, FH Fletcher, K Padalino, S Freeman, C Izumi, N Lerche, R Phillips, TW Sangster, TC TI Core performance and mix in direct-drive spherical implosions with high uniformity SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID INERTIAL CONFINEMENT FUSION; OMEGA-LASER SYSTEM; TARGETS; COMPRESSION AB The performance of gas-filled, plastic-shell implosions has significantly improved with advances in on-target uniformity on the 60-beam OMEGA laser system [T. R. Boehly, D. L. Brown, R. S. Craxton , Opt. Commun. 133, 495 (1997)]. Polarization smoothing (PS) with birefringent wedges and 1-THz-bandwidth smoothing by spectral dispersion (SSD) have been installed on OMEGA. The beam-to-beam power imbalance is less than or equal to5% rms. Implosions of 20-mum-thick CH shells (15 atm fill) using full beam smoothing (1-THz SSD and PS) have primary neutron yields and fuel areal densities that are similar to 70% larger than those driven with 0.35-THz SSD without PS. They also produce similar to 35% of the predicted one-dimensional neutron yield. The results described here suggest that individual-beam nonuniformity is no longer the primary cause of nonideal target performance. A highly constrained model of the core conditions and fuel-shell mix has been developed. It suggests that there is a "clean" fuel region, surrounded by a mixed region, that accounts for half of the fuel areal density. (C) 2001 American Institute of Physics. C1 Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. MIT, Ctr Plasma Fus, Cambridge, MA 02139 USA. SUNY Geneseo, Geneseo, NY 14454 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Meyerhofer, DD (reprint author), Univ Rochester, Laser Energet Lab, 250 E River Rd, Rochester, NY 14623 USA. RI Goncharov, Valeri/H-4471-2011; IZUMI, Nobuhiko/J-8487-2016 OI IZUMI, Nobuhiko/0000-0003-1114-597X NR 31 TC 70 Z9 71 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2251 EP 2256 DI 10.1063/1.1350964 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500060 ER PT J AU Cuneo, ME Vesey, RA Porter, JL Chandler, GA Fehl, DL Gilliland, TL Hanson, DL McGurn, JS Reynolds, PG Ruggles, LE Seamen, H Spielman, RB Struve, KW Stygar, WA Simpson, WW Torres, JA Wenger, DF Hammer, JH Rambo, PW Peterson, DL Idzorek, GC AF Cuneo, ME Vesey, RA Porter, JL Chandler, GA Fehl, DL Gilliland, TL Hanson, DL McGurn, JS Reynolds, PG Ruggles, LE Seamen, H Spielman, RB Struve, KW Stygar, WA Simpson, WW Torres, JA Wenger, DF Hammer, JH Rambo, PW Peterson, DL Idzorek, GC TI Development and characterization of a Z-pinch-driven hohlraum high-yield inertial confinement fusion target concept SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID ARRAY Z-PINCHES; WIRE-ARRAY; 2-DIMENSIONAL SIMULATIONS; POWER AB Initial experiments to study the Z-pinch-driven hohlraum high-yield inertial confinement fusion (ICF) concept of Hammer, Tabak, and Porter [Hammer , Phys. Plasmas 6, 2129 (1999)] are described. The relationship between measured pinch power, hohlraum temperature, and secondary hohlraum coupling ("hohlraum energetics") is well understood from zero-dimensional semianalytic, and two-dimensional view factor and radiation magnetohydrodynamics models. These experiments have shown the highest x-ray powers coupled to any Z-pinch-driven secondary hohlraum (26 +/-5 TW), indicating the concept could scale to fusion yields of > 200 MJ. A novel, single-sided power feed, double-pinch driven secondary that meets the pinch simultaneity requirements for polar radiation symmetry has also been developed. This source will permit investigation of the pinch power balance and hohlraum geometry requirements for ICF relevant secondary radiation symmetry, leading to a capsule implosion capability on the Z accelerator [Spielman , Phys. Plasmas 5, 2105 (1998)]. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cuneo, ME (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 26 TC 85 Z9 85 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2257 EP 2267 DI 10.1063/1.1348328 PN 2 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500061 ER PT J AU Marinak, MM Kerbel, GD Gentile, NA Jones, O Munro, D Pollaine, S Dittrich, TR Haan, SW AF Marinak, MM Kerbel, GD Gentile, NA Jones, O Munro, D Pollaine, S Dittrich, TR Haan, SW TI Three-dimensional HYDRA simulations of National Ignition Facility targets SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; INERTIAL CONFINEMENT FUSION; 3-DIMENSIONAL SIMULATIONS; CAPSULE DESIGN; DENSE-PLASMAS; NOVA; IMPLOSION; GROWTH; BEAMS; MODEL AB The performance of a targets designed for the National Ignition Facility (NIF) are simulated in three dimensions using the HYDRA multiphysics radiation hydrodynamics code. [M. Marinak , Phys. Plasmas 5, 1125 (1998)] In simulations of a cylindrical NIF hohlraum that include an imploding capsule, all relevant hohlraum features and the detailed laser illumination pattern, the motion of the wall material inside the hohlraum shows a high degree of axisymmetry. Laser light is able to propagate through the entrance hole for the required duration of the pulse. Gross hohlraum energetics mirror the results from an axisymmetric simulation. A NIF capsule simulation resolved the full spectrum of the most dangerous modes that grow from surface roughness. Hydrodynamic instabilities evolve into the weakly nonlinear regime. There is no evidence of anomalous low mode growth driven by nonlinear mode coupling. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Marinak, MM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 37 TC 287 Z9 288 U1 3 U2 21 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2275 EP 2280 DI 10.1063/1.1356740 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500063 ER PT J AU Herrmann, MC Tabak, M Lindl, JD AF Herrmann, MC Tabak, M Lindl, JD TI Ignition scaling laws and their application to capsule design SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID CONFINEMENT FUSION-TARGETS; HEAVY-ION; FACILITY; DRIVEN; GAIN AB This paper investigates the amount of energy required to ensure the ignition of an inertial confinement fusion capsule. First, a series of one-dimensional LASNEX [G. B. Zimmerman and W. L. Kruer, Plasma Phys. Controlled Fusion 2, 51 (1975)] simulations are performed to create a database of barely ignited capsules that span the parameter regime of interest. This database is used to develop scaling laws for the ignition energy in terms of both the stagnated capsule parameters and the in-flight capsule parameters, and to explore the connection between these two parameter sets. We then examine how much extra energy is required to overcome the effect of the inevitable surface imperfections that are amplified during the implosion process. These perturbations can lead to break up of the capsule in flight or to mix of cold fuel into the hot spot, both of which can cause the capsule to fail. As an example, a family of capsules with fixed adiabat, drive pressure, and absorbed energy is studied; the capsule from this family that is maximally robust to these failure modes is found. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Herrmann, MC (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 22 TC 41 Z9 43 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2296 EP 2304 DI 10.1063/1.1364516 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500066 ER PT J AU Mason, RJ Hollowell, DE Schappert, GT Batha, SH AF Mason, RJ Hollowell, DE Schappert, GT Batha, SH TI Long term instability growth of radiatively driven thin planar shells SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID LASER; SYSTEM; NOVA AB The Rayleigh-Taylor instability of radiatively driven thin copper foils is studied under pure ablation, as well as with beryllium buffers to provide additional pressure drive, in support of the target design for Inertial Confinement Fusion. Modeling was done with the RAGE adaptive mesh refinement code [R. M. Baltrusaitis, M. L. Gittings, R. P. Weaver, R. F. Benjamin, and J. M. Budzinski, Phys. Fluids 8, 2471 (1996)] of experiments done on the OMEGA [T. R. Boehly, D. L. Brown, R. S. Craxton , Opt. Commun. 133, 495 (1997)] laser. The copper foils were typically 11.5 mum thick with 0.45 mum amplitude and 45 mum wavelength cosine surface perturbations. The beryllium layer was 5 mum thick. The drive was a "PS26"-like [J. D. Lindl, Phys. Plasmas 2, 3933 (1995)] laser pulse delivering peak 160-185 eV radiation temperatures. Good agreement between experiment and simulation has been obtained out to 4.5 ns. Mechanisms for late time agreement are discussed. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mason, RJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 20 TC 8 Z9 8 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2338 EP 2343 DI 10.1063/1.1354150 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500071 ER PT J AU Budil, KS Lasinski, B Edwards, MJ Wan, AS Remington, BA Weber, SV Glendinning, SG Suter, L Stry, PE AF Budil, KS Lasinski, B Edwards, MJ Wan, AS Remington, BA Weber, SV Glendinning, SG Suter, L Stry, PE TI The ablation-front Rayleigh-Taylor dispersion curve in indirect drive SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID INERTIAL CONFINEMENT FUSION; CONSISTENT STABILITY ANALYSIS; GROWTH-RATES; INSTABILITY EXPERIMENTS; PERTURBATION GROWTH; LASER-FUSION; SINGLE-MODE; TARGETS; NOVA; RADIATION AB The Rayleigh-Taylor (RT) instability, which occurs when a lower-density fluid accelerates a higher-density layer, is common in nature. At an ablation front a sharp reduction in the growth rate of the instability at short wavelengths can occur, in marked contrast to the classical case where growth rates are highest at the shortest wavelengths. Theoretical and numerical investigations of the ablative RT instability are numerous and differ considerably on the level of stabilization expected. Presented here are the results of a series of laser experiments designed to measure the RT dispersion curve for a radiatively driven sample. Aluminum foils with imposed sinusoidal perturbations ranging in wavelength from 10 to 70 mum were ablatively accelerated with a radiation drive generated in a gold cylindrical hohlraum. A strong shock wave compresses the package followed by an similar to2 ns period of roughly constant acceleration and the experiment is diagnosed via face-on radiography. Perturbations with wavelengths greater than or equal to 20 mum experienced substantial growth during the acceleration phase while shorter wavelengths showed a sharp drop off in overall growth. These experimental results compared favorably to calculations with a two-dimensional radiation-hydrodynamics code, however, the growth is significantly affected by the rippled shock launched by the drive. Due to the influence of the rippled shock transit phase of the experiment and ambiguities associated with directly extracting the physical amplitude of the perturbations at the ablation front from the simulations, direct comparison to the ablation front RT theory of Betti [Phys. Plasmas 5, 1446 (1998)], was difficult. Instead, a numerical "experiment" was constructed that minimized the influence of the shock and this was compared to the Betti model showing quite good agreement. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Budil, KS (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-21, Livermore, CA 94550 USA. NR 36 TC 23 Z9 23 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2344 EP 2348 DI 10.1063/1.1356738 PN 2 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500072 ER PT J AU Pollaine, SM Bradley, DK Landen, OL Wallace, RJ Jones, OS Amendt, PA Suter, LJ Turner, RE AF Pollaine, SM Bradley, DK Landen, OL Wallace, RJ Jones, OS Amendt, PA Suter, LJ Turner, RE TI National Ignition Facility scale hohlraum asymmetry studies by thin shell radiography SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; X-RAY DRIVE; NOVA; TARGETS; MIXTURE; FUSION AB A necessary condition for igniting indirectly driven inertial confinement fusion (ICF) capsules on the National Ignition Facility (NIF) is controlling drive asymmetry to the 1% level [S. W. Haan, S. M. Pollaine, J. D. Lindl , Phys. Plasmas 2, 2480 (1995)]. Even flux-asymmetry modes (e.g., Legendre modes P-2, P-4, P-6, and P-8) must be reduced by hohlraum design and laser beam pointing. Odd flux-asymmetry modes (e.g., Legendre modes P-1, P-3, P-5, etc.) are theoretically removed by reflection symmetry across the hohlraum midplane [S. M. Pollaine and D. Eimerl, Nucl. Fusion 38, 1523 (1998)], but will be produced by power imbalance, laser beam pointing errors, and target fabrication errors. An experimental campaign is now being conducted on the University of Rochester's Omega laser to measure higher order (P-4 and higher) flux asymmetry modes inside hohlraums that approximate the conditions of a NIF hohlraum during the 90 eV early drive phase [S. W. Haan, S. M. Pollaine, J. D. Lindl , Phys. Plasmas 2, 2480 (1995)]. These experiments use a new point-projection backlighting technique [O. L. Landen, D. R. Farley, S. G. Glendinning , Rev. Sci. Instrum. 72, 627 (2001)] to cast high quality 4.7 keV radiographs of thin 2 mm diameter Ge-doped CH shells designed to enhance sensitivity to drive asymmetries. Distortions in the position of the limb of the shells resulting primarily from drive asymmetries are measured to an accuracy of 2 mum. The linearity and sensitivity of thin imploding shells to flux asymmetry makes it possible to achieve this degree of accuracy, which is sufficient for NIF ignition symmetry tuning. The promising results to date permit the comparison of measured and predicted distortions and, by inference, drive asymmetries for the first eight asymmetry modes. (C) 2001 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Pollaine, SM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 23 TC 29 Z9 30 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2357 EP 2364 DI 10.1063/1.1364514 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500074 ER PT J AU Colgate, SA Li, H Pariev, V AF Colgate, SA Li, H Pariev, V TI The origin of the magnetic fields of the universe: The plasma astrophysics of the free energy of the universe SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID ROSSBY-WAVE INSTABILITY; ACCRETION DISKS AB The interpretation of Faraday rotation measure maps of active galactic nuclei (AGNs) within galaxy clusters has revealed ordered or coherent regions, L(mag)similar to 50-100 kpc (similar to 3x10(23) cm), that are populated with large, similar to 30 muG magnetic fields. The magnetic energy of these coherent regions is L-mag(3)(B-2/8 pi)similar to 10(59-60) ergs, and the total magnetic energy over the whole cluster (similar to1 Mpc across) is expected to be even larger. Understanding the origin and role of these magnetic fields is a major challenge to plasma astrophysics. A sequence of physical processes that are responsible for the production, redistribution, and dissipation of these magnetic fields is proposed. These fields are associated with single AGNs within the cluster and therefore with all galaxies during their AGN (active galactic nucleus or quasar) phase, simply because only the central supermassive black holes (similar to 10(8)M) formed during the AGN phase have an accessible energy of formation, similar to 10(61) ergs, that can account for the magnetic field energy budget. An alpha-Omega dynamo process has been proposed that operates in an accretion disk around a black hole. The disk rotation naturally provides a large winding number, similar to 10(11) turns, sufficient to make both large gain and large flux. The helicity of the dynamo can be generated by the differential plume rotation derived from star-disk collisions. This helicity generation process has been demonstrated in the laboratory and the dynamo gain was simulated numerically. A liquid sodium analog of the dynamo is being built. Speculations are that the back reaction of the saturated dynamo will lead to the formation of a force-free magnetic helix, which will carry the energy and flux of the dynamo away from the accretion disk and redistribute the field within the clusters and galaxy walls. The magnetic reconnection of a small fraction of this energy logically is the source of the AGN (active galactic nucleus or quasar) luminosity, and the remainder of the field energy should then dominate the free energy of the present-day universe. The reconnection of this intergalactic field during a Hubble time is the only sufficient source of energy necessary to produce an extragalactic cosmic ray energy spectrum as observed in this galaxy, and at the same time allow this spectrum to escape to the galaxy voids faster than the GZK (blackbody radiation) loss. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. PN Lebedev Phys Inst, Moscow 11792, Russia. RP Colgate, SA (reprint author), Univ Calif Los Alamos Natl Lab, T6, Los Alamos, NM 87545 USA. NR 19 TC 35 Z9 36 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2425 EP 2431 DI 10.1063/1.1351827 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500083 ER PT J AU Robey, HF Kane, JO Remington, BA Drake, RP Hurricane, OA Louis, H Wallace, RJ Knauer, J Keiter, P Arnett, D Ryutov, DD AF Robey, HF Kane, JO Remington, BA Drake, RP Hurricane, OA Louis, H Wallace, RJ Knauer, J Keiter, P Arnett, D Ryutov, DD TI An experimental testbed for the study of hydrodynamic issues in supernovae SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID OMEGA-LASER-SYSTEM; RICHTMYER-MESHKOV INSTABILITY; RAYLEIGH-TAYLOR; INTENSE LASERS; BLAST WAVES; SHOCK-WAVES; GROWTH; SN-1987A; PERTURBATIONS; ASTROPHYSICS AB More than a decade after the explosion of supernova 1987A, unresolved discrepancies still remain in attempts to numerically simulate the mixing processes initiated by the passage of a very strong shock through the layered structure of the progenitor star. Numerically computed velocities of the radioactive Ni-56 and Co-56, produced by shock-induced explosive burning within the silicon layer, for example, are still more than 50% too low as compared with the measured velocities. To resolve such discrepancies between observation and simulation, an experimental testbed has been designed on the Omega Laser for the study of hydrodynamic issues of importance to supernovae (SNe). In this paper, results are presented from a series of scaled laboratory experiments designed to isolate and explore several issues in the hydrodynamics of supernova explosions. The results of the experiments are compared with numerical simulations and are generally found to be in reasonable agreement. (C) 2001 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Michigan, Ann Arbor, MI 48105 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. Univ Arizona, Tucson, AZ USA. RP Robey, HF (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Drake, R Paul/I-9218-2012; Keiter, Paul/J-3037-2013 OI Drake, R Paul/0000-0002-5450-9844; NR 61 TC 65 Z9 66 U1 1 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2446 EP 2453 DI 10.1063/1.1352594 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500086 ER PT J AU Leemans, WP Rodgers, D Catravas, PE Geddes, CGR Fubiani, G Esarey, E Shadwick, BA Donahue, R Smith, A AF Leemans, WP Rodgers, D Catravas, PE Geddes, CGR Fubiani, G Esarey, E Shadwick, BA Donahue, R Smith, A TI Gamma-neutron activation experiments using laser wakefield accelerators SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID ELECTRON ACCELERATION; PLASMAS; PULSES; RAMAN AB Gamma-neutron activation experiments have been performed with relativistic electron beams produced by a laser wakefield accelerator. The electron beams were produced by tightly focusing (spot diameter approximate to6 mum) a high power (up to 10 TW), ultra-short (greater than or equal to 50 fs) laser beam from a high repetition rate (10 Hz) Ti:sapphire (0.8 mum) laser system, onto a high density (> 10(19) cm(-3)) pulsed gasjet of length approximate to1.5 mm. Nuclear activation measurements in lead and copper targets indicate the production of electrons with energy in excess of 25 MeV. This result was confirmed by electron distribution measurements using a bending magnet spectrometer. Measured gamma -ray and neutron yields are also found to be in reasonable agreement with simulations using a Monte Carlo transport code. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Leemans, WP (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 19 TC 101 Z9 104 U1 3 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2510 EP 2516 DI 10.1063/1.1352617 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500095 ER PT J AU Kaganovich, I AF Kaganovich, I TI Negative ion density fronts SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID CHARGED-SPECIES PROFILES; POSITIVE-COLUMN; ELECTRONEGATIVE GASES; PLASMA DISCHARGES; CHLORINE PLASMAS; RF DISCHARGES; DEPOSITION; AFTERGLOW AB Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature T-e much larger than ion temperature T-i, T-e>>T-i). The boundary separating a plasma containing negative ions, and a plasma without negative ions, is usually thin so that the negative ion density falls rapidly to zero-forming a negative ion density front. Theoretical, experimental, and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow) are reviewed. During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in the analysis of plasma density profile evolution in strongly nonisothermal plasmas. (C) 2001 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kaganovich, I (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 51 TC 19 Z9 20 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2540 EP 2548 DI 10.1063/1.1343088 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500099 ER PT J AU Raitses, Y Fisch, NJ AF Raitses, Y Fisch, NJ TI Parametric investigations of a nonconventional Hall thruster SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 42nd Annual Meeting of the Division of Plasma Physics Of the American-Physical-Society/10th International Congress on Plasma Physics CY OCT 23-27, 2000 CL QUEBEC CITY, CANADA SP Amer Phys Soc, Div Plasma Phys ID STATIONARY PLASMA THRUSTER; OSCILLATIONS AB Hall thrusters might better scale to low power with nonconventional geometry. A 9 cm cylindrical, ceramic-channel, Hall thruster with a cusp-type magnetic field distribution has been investigated. It exhibits discharge characteristics similar to conventional coaxial Hall thrusters, but does not expose as much channel surface. Significantly, its operation is not accompanied by large amplitude discharge low frequency oscillations. (C) 2001 American Institute of Physics. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Raitses, Y (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 25 TC 67 Z9 69 U1 2 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2001 VL 8 IS 5 BP 2579 EP 2586 DI 10.1063/1.1355318 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 423QP UT WOS:000168188500104 ER PT J AU Foy, BR AF Foy, BR TI Los Alamos fire posed little radiation hazard SO PHYSICS TODAY LA English DT Letter C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Foy, BR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 1 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 0031-9228 J9 PHYS TODAY JI Phys. Today PD MAY PY 2001 VL 54 IS 5 BP 90 EP 90 DI 10.1063/1.1381130 PG 1 WC Physics, Multidisciplinary SC Physics GA 427HJ UT WOS:000168398500034 ER PT J AU Ruhl, H Bulanov, SV Cowan, TE Liseikina, TV Nickles, P Pegoraro, F Roth, M Sandner, W AF Ruhl, H Bulanov, SV Cowan, TE Liseikina, TV Nickles, P Pegoraro, F Roth, M Sandner, W TI Computer simulation of the three-dimensional regime of proton acceleration in the interaction of laser radiation with a thin spherical target SO PLASMA PHYSICS REPORTS LA English DT Article ID HIGH-INTENSITY LASER; FAST IGNITER; UNDERDENSE PLASMAS; RELATIVISTIC IONS; COLLIMATED BEAMS; PULSES; DENSITY; GENERATION; ABSORPTION; FUSION AB Results from particle-in-cell simulations of the three-dimensional regime of proton acceleration in the interaction of laser radiation with a thin spherical target are presented. It is shown that the density of accelerated protons can be several times higher than that in conventional accelerators. The focusing of fast protons created in the interaction of laser radiation with a spherical target is demonstrated. The focal spot of fast protons is localized near the center of the sphere. The conversion efficiency of laser energy into fast ion energy attains 5%. The acceleration mechanism is analyzed and the electron and proton energy spectra are obtained. (C) 2001 MAIK "Nauka/Interperiodica". C1 Max Born Inst, D-12489 Berlin, Germany. Gesell Schwerionenforsch GmbH, D-64291 Darmstadt, Germany. Ist Nazl Fis Mat, Pisa, Italy. Russian Acad Sci, Siberian Div, Inst Computat Technol, Novosibirsk 630090, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Russian Acad Sci, Inst Gen Phys, Moscow 117942, Russia. RP Ruhl, H (reprint author), Max Born Inst, Max Born Str 2A, D-12489 Berlin, Germany. RI Bulanov, Sergei/A-1721-2013; Liseykina, Tatyana/B-1229-2009; Cowan, Thomas/A-8713-2011; OI Liseykina, Tatyana/0000-0002-5070-3543; Cowan, Thomas/0000-0002-5845-000X; Pegoraro, Francesco/0000-0002-7216-5491 NR 28 TC 71 Z9 71 U1 1 U2 3 PU MAIK NAUKA/INTERPERIODICA PUBL PI MELVILLE PA C/O AMERICAN INST PHYSICS, 2 HUNTINGTON QUANDRANGLE, STE 1NO1, MELVILLE, NY 11747-4502 USA SN 1063-780X J9 PLASMA PHYS REP+ JI Plasma Phys. Rep. PD MAY PY 2001 VL 27 IS 5 BP 363 EP 371 DI 10.1134/1.1371596 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 442LP UT WOS:000169287500001 ER PT J AU Thornton, E AF Thornton, E TI Safety concerns? - Response SO POLLUTION ENGINEERING LA English DT Letter C1 Pacific NW Natl Lab, Environm Technol Div, Field Hydrol & Chem Grp, Richland, WA 99352 USA. RP Thornton, E (reprint author), Pacific NW Natl Lab, Environm Technol Div, Field Hydrol & Chem Grp, Richland, WA 99352 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU CAHNERS-DENVER PUBLISHING CO PI OAK BROOK PA 2000 CLEARWATER DR, OAK BROOK, IL 60523-8809 USA SN 0032-3640 J9 POLLUT ENG JI Pollut. Eng. PD MAY PY 2001 VL 33 IS 4 BP 6 EP 6 PG 1 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 431WK UT WOS:000168654600004 ER PT J AU Striolo, A Prausnitz, JM AF Striolo, A Prausnitz, JM TI Osmotic second virial coefficient for linear and star poly(ethylene oxide) SO POLYMER LA English DT Article DE osmotic second virial coefficient; poly(ethylene oxide); star polymer ID POLYMERS AB Experimental osmotic second virial coefficients are reported for linear and star poly(ethylene oxide) in water and 1-propanol in the temperature region 25-55 degreesC. All measured osmotic second virial coefficients are positive. Ar. fixed temperature, the osmotic second virial coefficient for star poly(ethylene oxide) is lower than that for the linear polymer of comparable molecular weight. The osmotic second Virial coefficient for star poly(ethylene oxide) decreases with rising temperature in both water and 1-propanol. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Prausnitz, JM (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RI Striolo, Alberto/G-2926-2011 NR 11 TC 7 Z9 7 U1 0 U2 10 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAY PY 2001 VL 42 IS 10 BP 4773 EP 4775 DI 10.1016/S0032-3861(00)00649-2 PG 3 WC Polymer Science SC Polymer Science GA 403NZ UT WOS:000167050500036 ER PT J AU Friedman, DJ Olson, JM AF Friedman, DJ Olson, JM TI Analysis of Ge junctions for GaInP/GaAs/Ge three-junction solar cells SO PROGRESS IN PHOTOVOLTAICS LA English DT Article ID TANDEM AB We study Ge solar cells with epitaxial GaInP windows for application as the third junction of GaInP/GaAs/Ge three-junction solar cells. We demonstrate Ge junctions with open-circuit voltages above 230 mV, fill factors above 65%, and internal quantum efficiencies of similar to 90%. By varying separately the base and emitter contributions to the junction dark current, we deduce the factors limiting the performance of this device, and we project the improvement to the device performance that may be obtainable if key limiting factors such as the emitter surface-recombination velocity can be mittgated. Published in 2001 by John Wiley & Sons, Ltd. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Friedman, DJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 13 TC 37 Z9 40 U1 3 U2 21 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD MAY-JUN PY 2001 VL 9 IS 3 BP 179 EP 189 DI 10.1002/pip.365 PG 11 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 435LT UT WOS:000168883500002 ER PT J AU Plummer, EW Ismail Matzdorf, R Melechko, AV Zhang, JD AF Plummer, EW Ismail Matzdorf, R Melechko, AV Zhang, JD TI The next 25 years of surface physics SO PROGRESS IN SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 20th International Seminar on Surface Physics CY JUN 19-24, 2000 CL KUDOWA ZDROJ, POLAND SP Univ Wroclaw, Inst Exptl Phys, Polish State Comm Sci Res, German Phys Soc, Phys Electr GmbH, Shimadzu Polska - Analityka ID CHARGE-DENSITY-WAVE; SCANNING-TUNNELING-MICROSCOPY; PHASE-SEPARATION; EXTRINSIC DEFECTS; MANGANESE OXIDES; TRANSITION; SUPERCONDUCTIVITY; FERROMAGNETISM; RUSR2GDCU2O8; MANGANITES AB The 20th International Seminar on Surface Physics commemorates the last quarter of a century in surface physics and serves as the commencement of the next millennium. This article attempts to identify the guiding directions for the next 25 years of surface physics relevant to the field of condensed matter physics. The message is that Surface Science and specifically surface physics must undergo a Cultural Revolution from a technique-driven to science-driven discipline. There are tremendously exciting opportunities for surface physics but to take advantage of them will require a change in our culture and most importantly in the education of the next generation of surface scientist. Some of the opportunities that exist in complex highly correlated systems in reduced dimensionality will be presented to illustrate the pivotal role that surface physicists can play in contemporary Condensed Matter Physics. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Tennessee, Dept Phys & Astron, South Coll 200, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Wurzburg, D-97074 Wurzburg, Germany. Florida Int Univ, Dept Phys, Miami, FL 33199 USA. RP Plummer, EW (reprint author), Univ Tennessee, Dept Phys & Astron, South Coll 200, Knoxville, TN 37996 USA. RI Melechko, Anatoli/B-8820-2008 NR 48 TC 19 Z9 19 U1 0 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6816 J9 PROG SURF SCI JI Prog. Surf. Sci. PD MAY-AUG PY 2001 VL 67 IS 1-8 BP 17 EP 44 DI 10.1016/S0079-6816(01)00014-4 PG 28 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 460QC UT WOS:000170319200006 ER PT J AU Inokuti, M AF Inokuti, M TI Ugo Fano (1912-2001) - In memoriam SO RADIATION RESEARCH LA English DT Biographical-Item C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Inokuti, M (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 1 TC 0 Z9 0 U1 0 U2 2 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 2001 VL 155 IS 5 BP 753 EP 754 DI 10.1667/0033-7587(2001)155[0753:UF]2.0.CO;2 PG 2 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 429RL UT WOS:000168530700015 PM 11302775 ER PT J AU Finn, MG AF Finn, MG TI Market heats up for S/E doctorates SO RESEARCH-TECHNOLOGY MANAGEMENT LA English DT Article AB Anecdotal reports indicate that the job prospects for Ph.D. scientists and engineers in the United States have been improving. Available data support this view degree awards continue their decline while research spending grew at a near record pace during the second half of the 1990s. Foreign students helped increase supply from U.S. universities during the early 1990s, but their increase has leveled off There is little information, however, on the migration of people with doctorates earned abroad. Should research spending remain strong the market for doctorates in science and engineering is likely to improve further because graduate enrollment responds with a lag. Needs in some ar eas are surely going to be met in part by increased numbers of migrants with doctorates from foreign institutions. C1 Oak Ridge Associated Univ, Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. RP Finn, MG (reprint author), Oak Ridge Associated Univ, Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU INDUSTRIAL RESEARCH INST INC PI WASHINGTON PA 1550 M ST., NW, WASHINGTON, DC 20005 USA SN 0895-6308 J9 RES TECHNOL MANAGE JI Res.-Technol. Manage. PD MAY-JUN PY 2001 VL 44 IS 3 BP 39 EP 43 PG 5 WC Business; Engineering, Industrial; Management SC Business & Economics; Engineering GA 428EG UT WOS:000168448000010 ER PT J AU Knyazev, BA Greenly, JB Hammer, DA Krastelev, EG Cuneo, ME AF Knyazev, BA Greenly, JB Hammer, DA Krastelev, EG Cuneo, ME TI Telescopic refractive index gradient diagnostic of an ion diode anode plasma SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID PHOTOTHERMAL DEFLECTION SPECTROSCOPY; LASER; MEDIA AB We present a general analysis of possible variants of refractive index gradient (RING) diagnostics with a laser beam probe. Using a differential bicell photodiode as a detector, the sensitivity, dynamic range, and geometric restrictions of RING deflectometry have been found for lensless, one lens, and "three-telescope" optical schemes. The three-telescope method is found to be the most flexible and easily aligned. If the refracted/deflected laser beam cross section in the back focal plane of the output lens is also recorded using a fast framing camera, measurements of the beam deflection and its spatial frequency spectrum after passing through the refractive medium can be obtained simultaneously. A general relation is presented between the Fourier transform of a Gaussian beam by the output lens and the spatial frequency spectrum of the inhomogeneities. From these considerations, we present the specific design of a RING diagnostic for study of anode plasma evolution in a magnetically insulated ion diode on the Cornell Beam Research Accelerator (COBRA) (800 kV, 80 ns pulse). The maximum density gradient was found to be located about 0.4 mm from the anode surface at the peak of the diode voltage pulse. The electron density at this position was about 2x10(15) cm(-3). The transverse spatial frequency distribution of the probe laser beam after passing through the anode plasma was recorded using the optical Fourier transform technique. This experiment demonstrates that the combined integrated deflection. (RING) and Fourier transform optical techniques can give a great deal of information about this thin (similar to1 mm) anode plasma layer. (C) 2001 American Institute of Physics. C1 Cornell Univ, Plasma Studies Lab, Ithaca, NY 14853 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Novosibirsk State Univ, Novosibirsk 630090, Russia. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. RP Knyazev, BA (reprint author), Cornell Univ, Plasma Studies Lab, 369 Upson Hall, Ithaca, NY 14853 USA. NR 24 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 2001 VL 72 IS 5 BP 2310 EP 2321 DI 10.1063/1.1362457 PG 12 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 424VH UT WOS:000168254300014 ER PT J AU Qiao, ZJ AF Qiao, ZJ TI Generalized r-matrix structure and algebro-geometric solution for integrable system SO REVIEWS IN MATHEMATICAL PHYSICS LA English DT Review DE Lax matrix; r-matrix structure; integrable system; algebro-geometric solution ID NONLINEAR EVOLUTION-EQUATIONS; HEISENBERG SPIN CHAIN; HAMILTONIAN-STRUCTURE; LAX EQUATIONS; LIE-ALGEBRAS; COUPLED KDV; HIERARCHY; FLOWS; TODA; NEUMANN AB The purpose of this paper is to construct a generalized r-matrix structure of finite dimensional systems and an approach to obtain the algebro-geometric solutions of integrable nonlinear evolution equations (NLEEs). Our starting point is a generalized Lax matrix instead of the usual Lax pair. The generalized r-matrix structure and Hamiltonian functions are presented on the basis of fundamental Poisson bracket. It can be clearly seen that various nonlinear constrained (c-) and restricted (r-) systems, such as the c-AKNS, c-MKdV, c-Toda, r-Toda, c-Levi, etc, are derived from the reductions of this structure. All these nonlinear systems have r-matrices, and are completely integrable in Liouville's sense. Furthermore, our generalized structure is developed to become an approach to obtain the algebro-geometric solutions of integrable NLEEs. Finally, the two typical examples are considered to illustrate this approach: the infinite or periodic Toda lattice equation and the AKNS equation with the condition of decay at infinity or periodic boundary. C1 Fudan Univ, Inst Math, Shanghai 200433, Peoples R China. Univ Gesamthsch Kassel, Fachbereich 17, D-34109 Kassel, Germany. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Qiao, ZJ (reprint author), Fudan Univ, Inst Math, Shanghai 200433, Peoples R China. NR 58 TC 52 Z9 53 U1 0 U2 3 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0129-055X J9 REV MATH PHYS JI Rev. Math. Phys. PD MAY PY 2001 VL 13 IS 5 BP 545 EP 586 DI 10.1142/S0129055X01000752 PG 42 WC Physics, Mathematical SC Physics GA 440NN UT WOS:000169181400001 ER PT J AU Zhukov, AE Zhao, R Specht, P Ustinov, VM Anders, A Weber, ER AF Zhukov, AE Zhao, R Specht, P Ustinov, VM Anders, A Weber, ER TI MBE growth of (In)GaAsN on GaAs using a constricted DC plasma source SO SEMICONDUCTOR SCIENCE AND TECHNOLOGY LA English DT Article ID MOLECULAR-BEAM EPITAXY; LASERS; DEPENDENCE; GAINNAS; ENERGY; GANAS AB (In)GaAsN epilayers were grown on GaAs substrates by molecular beam epitaxy (MBE) with a DC constricted-plasma source. Nitrogen incorporation efficiency. crystalline quality, surface morphology and luminescent properties: of the epilayers were studied and correlated with various operation regimes of the source. The nitrogen incorporation efficiency grows with increasing plasma discharge current. The maximum nitrogen concentration in the epilayer is as high as 3.7 %. GaAsN as thick as 0.35 mum can be pseudomorphically grown on GaAs, and photoluminescence is observed at room temperature. The crystalline quality and surface morphology of an epilayer can also be improved by reducing the ion damage at low plasma discharge current. The DC constricted-plasma source is a promising alternative nitrogen plasma source for investigating InGaAsN materials. C1 Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Zhukov, AE (reprint author), Russian Acad Sci, AF Ioffe Physicotech Inst, 26 Politekhnicheskaya, St Petersburg 194021, Russia. RI Zhukov, Alexey/A-5523-2014; Ustinov, Viktor/J-3545-2013; Anders, Andre/B-8580-2009 OI Zhukov, Alexey/0000-0002-4579-0718; Anders, Andre/0000-0002-5313-6505 NR 14 TC 4 Z9 4 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0268-1242 J9 SEMICOND SCI TECH JI Semicond. Sci. Technol. PD MAY PY 2001 VL 16 IS 5 BP 413 EP 419 DI 10.1088/0268-1242/16/5/323 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA 433WJ UT WOS:000168783400027 ER PT J AU Ross, DS Hales, HC Shea-McCarthy, GC Lanzirotti, A AF Ross, DS Hales, HC Shea-McCarthy, GC Lanzirotti, A TI Sensitivity of soil manganese oxides: Drying and storage cause reduction SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID HUMIC SUBSTANCES; OXIDATION; BIRNESSITE; CHEMISTRY; TRANSFORMATION; SPECTROSCOPY; CHROMIUM; BUSERITE; MN(IV) AB Effects of sample treatment must be well understood to avoid artifacts during analysis. The effect of drying and storage was examined on nine medium- to high-Mn aerobic soils using extractable Mn(II), the Cr Oxidation Test, estimated soluble C, and XANES spectroscopy, Long-term storage (430 d) at 3 degreesC had little effect on the Cr test. Air drying at room temperature (25 degreesC +/- 3 degreesC) caused a drop in the Cr test within 24 h, with a further decline to as low as 45% of the original after 72 h, and less than 2% after 264 d. Extractability of Mn with pH 4.8 NH4OAc increased nearly linearly over the same time period from 0.2 mmol kg(-1) to as high as 2.3 mmol kg(-1). Increases in the absorbance of the extract at 360 um, an estimate or soluble C, were well correlated within each soil with the increase in Mn(II), Pretreatments to remove soluble organics did not cause any increases in the Cr test of dried samples, Therefore, the loss of Cr oxidizing ability appears to be due to reduction of the oxides, not because of increased reduction of the Cr(VI) formed, No changes in XANES spectra were found after short-term air drying at room temperature, but in the three samples examined after 428 d of drying, the main-edge position had a downward shift of about 1.5 eV, indicating reduction, These results confirm previous findings that studies on the reactivity of soil Mn oxides need to avoid sample drying. C1 Univ Vermont, Dept Plant & Soil Sci, Burlington, VT 05405 USA. Univ Chicago, CARS, Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ross, DS (reprint author), Univ Vermont, Dept Plant & Soil Sci, Hills Bldg, Burlington, VT 05405 USA. RI Ross, Donald/A-4477-2008 OI Ross, Donald/0000-0002-5390-6602 NR 35 TC 19 Z9 22 U1 0 U2 18 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD MAY-JUN PY 2001 VL 65 IS 3 BP 736 EP 743 PG 8 WC Soil Science SC Agriculture GA 445NT UT WOS:000169464500015 ER PT J AU Ross, DS Hales, HC Shea-McCarthy, GC Lanzirotti, A AF Ross, DS Hales, HC Shea-McCarthy, GC Lanzirotti, A TI Sensitivity of soil manganese oxides: XANES spectroscopy may cause reduction SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID RAY-ABSORPTION-SPECTROSCOPY; MICROBIAL OXIDATION; EXAFS SPECTROSCOPY; COMPLEX; BIRNESSITE; STATE AB The examination of soils by x-ray absorption near-edge structure (XANES) spectroscopy can provide valuable clues for determining the structure and composition of Mn oxides. XANES experiments can be conducted at ambient temperatures using field-moist samples. This feature is attractive in the study of soil Mn because of the well-documented effects of sample drying on reactivity, The present study was undertaken to determine whether the analysis of field-moist soils by XANES spectroscopy has an effect on the oxidation state of the Mn, Repeated scans were taken on the same spot using seven medium- to high-Mn soils, In all 10 experiments with untreated soils, the main absorption edge dropped in relative energy in successive scans, indicating reduction of Mn. The change in eV was as high as 1.7 eV after 150 min of exposure time. After a series of scans showing reduction, small movement of the sample in the x-ray beam and reexamination showed no reduction, indicating that the effect was limited to the x-ray spot, Modeling the change with Mn(II) was successful and showed increases in reduced Mn between 6 and 20% after three to five repeated scans, The slopes of eV change vs. exposure time were remarkably similar in most experiments, even with large differences in the density of photons between runs, Comparisons of initial moist scans with those of recently air-dried samples found little difference, suggesting minimal reduction in a single XANES scan under our experimental conditions. C1 Univ Vermont, Dept Plant & Soil Sci, Burlington, VT 05405 USA. Univ Chicago, CARS, Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ross, DS (reprint author), Univ Vermont, Dept Plant & Soil Sci, Hills Bldg, Burlington, VT 05405 USA. RI Ross, Donald/A-4477-2008 OI Ross, Donald/0000-0002-5390-6602 NR 20 TC 18 Z9 19 U1 0 U2 15 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD MAY-JUN PY 2001 VL 65 IS 3 BP 744 EP 752 PG 9 WC Soil Science SC Agriculture GA 445NT UT WOS:000169464500016 ER PT J AU Ryutova, M Habbal, S Woo, R Tarbell, T AF Ryutova, M Habbal, S Woo, R Tarbell, T TI Photospheric network as the energy source for the quiet-Sun corona SO SOLAR PHYSICS LA English DT Article ID SOLAR-WIND; TRANSITION REGION; SCALE STRUCTURES; ATMOSPHERE; FLOW AB We propose a mechanism for the formation of a magnetic energy avalanche based on highly dynamic phenomena within the ubiquitous small-scale network magnetic elements in the quiet photosphere. We suggest that this mechanism may provide constant mass and energy supply for the corona and fast wind. Constantly emerging from sub-surface layers, flux tubes collide and reconnect generating magneto-hydrodynamic shocks that experience strong gradient acceleration in the sharply stratified photosphere/chromosphere region. Acoustic and fast magnetosonic branches of these waves lead to heating and/or jet formation due to cumulative effects (Tarbell et al., 1999). The Alfven waves generated by post-reconnection processes have quite a restricted range of parameters for shock formation, but their frequency, determined by the reconnection rate, may be high enough (omega similar or equal to 0.1-2.5 s(-1)) to carry the energy into the corona. We also suggest that the primary energy source for the fast wind lies far below the coronal heights, and that the chromosphere and transition region flows and also radiative transient form the base of the fast wind. The continuous supply of emerging magnetic flux tubes provides a permanent energy production process capable of explaining the steady character of the fast wind and its energetics. C1 Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Lockheed Martin Solar & Astrophys Lab, Palo Alto, CA 94304 USA. RP Ryutova, M (reprint author), Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. EM ryutova@beowulf.ucllnl.org; habbal@cfassp31.harvard.edu; rwoo@mail1.jpl.nasa.gov; tarbell@lmsal.com NR 28 TC 27 Z9 27 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD MAY PY 2001 VL 200 IS 1-2 BP 213 EP 234 DI 10.1023/A:1010374005082 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 456DK UT WOS:000170067700016 ER PT J AU Guzik, JA Neuforge-Verheecke, C Young, AC Epstein, RI Poulin, FM Schissel, JR AF Guzik, JA Neuforge-Verheecke, C Young, AC Epstein, RI Poulin, FM Schissel, JR TI Standard and non-standard solar models SO SOLAR PHYSICS LA English DT Article ID EQUATION-OF-STATE; STELLAR TURBULENT CONVECTION; THERMONUCLEAR REACTION-RATES; ELEMENT DIFFUSION; MASS-LOSS; HELIOSEISMIC CONSTRAINTS; NEUTRINO OSCILLATIONS; ENERGY-TRANSPORT; CROSS-SECTIONS; HEAVY-ELEMENT AB We summarize the physical input and assumptions commonly adopted in modern standard solar models that also produce good agreement with solar oscillation frequencies. We discuss two motivations for considering non-standard models: the solar neutrino problem and surface lithium abundance problem. We begin to explore the potential for mixed core models to solve the neutrino problem, and compare the structure, neutrino flux, and oscillation frequency predictions for several models in which the inner 25% of the radius is homogenized, taking into account the effects of non-local equilibrium abundances of (3)He. The results for the neutrino flux and helioseismic predictions are far from satisfactory, but such models have the potential to reduce the predicted (7)Be/(8)B neutrino flux ratio, and further studies are warranted. Finally, we discuss how much the neutrino problem can be alleviated in the framework of the standard solar model by using reaction rates, abundances and neutrino capture cross-sections at the limits of their uncertainties, while still satisfying the constraints of helioseismology. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Guzik, JA (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 84 TC 7 Z9 7 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD MAY PY 2001 VL 200 IS 1-2 BP 305 EP 321 DI 10.1023/A:1010398627973 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 456DK UT WOS:000170067700022 ER PT J AU Baca, AG Chang, PC Klem, JF Ashby, CIH Martin, DC AF Baca, AG Chang, PC Klem, JF Ashby, CIH Martin, DC TI Vertical AlGaAs/GaAs heterojunction bipolar transistors with 106 V breakdown SO SOLID-STATE ELECTRONICS LA English DT Article DE GaAs heterojunction bipolar transistor; high breakdown; vertical HBT AB A high voltage GaAs heterojunction bipolar transistor (HBT) with an open-base collector breakdown voltage of 106 V and an open-emitter breakdown voltage of 134 V has been demonstrated. A vertical structure with a doped GaAs substrate, a 9.0 mum thick collector doped to 2.0 x 10(15) cm(-3), and a backside collector contact were used to achieve this breakdown. The same breakdown voltage results were measured for HBTs with very different emitter areas and geometries, and are consistent with bulk breakdown in GaAs. Devices with 4 x 40 mum(2) emitters show DC current gain of 38 at 6000 A/cm(2). The device rf performance was limited due to extrinsic pad capacitance to the substrate, with f(t) and f(max) values of 1.16 and 3.0 GHz, respectively. However, intrinsic f(t) of approximately 16 GHz can be achieved through the use of thicker dielectric insulation. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Baca, AG (reprint author), Sandia Natl Labs, POB 5800,MS 0603, Albuquerque, NM 87185 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD MAY PY 2001 VL 45 IS 5 BP 721 EP 725 DI 10.1016/S0038-1101(01)00087-9 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 444JV UT WOS:000169397100015 ER PT J AU Somorjai, GA Chen, P AF Somorjai, GA Chen, P TI Surface materials: the frontier of solid state chemistry SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT XIVth International Symposium on the Reactivity of Solids (XIVth ISRS) CY AUG 27-31, 2000 CL BUDAPEST, HUNGARY SP Mol Rt Downstream Business Grp, Inst Environm Protect, Fdn Technol Progress Ind, Minist Educ, Deputy State Secretary Higher Educ & Sci, OMFB, Natl Comm Technol Dev, OTKA, NAtl Fdn Sci & Res, Off Int Cooperat Hungarian Acad Sci, Off Press, Szeged DE surface materials; molecular surface science; tools ID SUM-FREQUENCY GENERATION; SCANNING-TUNNELING-MICROSCOPY; 2ND HARMONIC-GENERATION; HIGH-PRESSURE; VIBRATIONAL SPECTROSCOPY; ELECTRON-MICROSCOPY; IN-SITU; PT(111); CO; HYDROGENATION AB Atomic scale studies of surfaces over the past 30 years greatly increased our knowledge of the chemical, mechanical, electrical, magnetic, and optical properties of surfaces. As a result, new technologies developed using these properties of surfaces, creating wealth, new scientific knowledge, and the need for new surface instrumentation with ever increasing time resolution. spatial and energy resolution. Over 60 techniques have been developed, most recently, those that can scrutinize, on the molecular level, the buried interfaces, solid-high pressure gas, solid-liquid, and solid-solid. The surface may be treated as a separate phase with different structure, composition and electronic properties. The new concepts of molecular surface science that were discovered include clean surface reconstruction, adsorbate induced restructuring, the high mobility of surface atoms at high pressures, and the unique importance of surface defects in controlling surface phenomena ranging From adsorption to heterogeneous catalysis. Future directions include studies of electrode surface under external potential conditions. polymer surfaces. studies of biomaterials. and studies of nanoclusters produced by chemical means or by electron beam lithography. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Natl Lawrence Berkeley Lab, Dept Chem, Div Mat Sci, Berkeley, CA 94720 USA. RP Somorjai, GA (reprint author), Univ Calif Berkeley, Natl Lawrence Berkeley Lab, Dept Chem, Div Mat Sci, D58 Hildebrand Hall,1460, Berkeley, CA 94720 USA. RI Chen, Peilin/E-2728-2010 OI Chen, Peilin/0000-0003-4154-0487 NR 54 TC 11 Z9 11 U1 2 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD MAY PY 2001 VL 141 SI SI BP 3 EP 19 DI 10.1016/S0167-2738(01)00715-9 PG 17 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 444VY UT WOS:000169421800002 ER PT J AU Jee, YA Ma, B Maroni, VA Li, M Fisher, BL Balachandran, U AF Jee, YA Ma, B Maroni, VA Li, M Fisher, BL Balachandran, U TI Texture development and superconducting properties of YBa2Cu3Ox thin films prepared by a solution process in low oxygen partial pressure SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID CRITICAL-CURRENT DENSITY; COATED CONDUCTORS; BUFFER LAYERS; YBCO FILMS; DEPOSITION; RAMAN; SPECTROSCOPY; FABRICATION; BA2YCU3O7-X; GROWTH AB YBa2Cu3Ox (YBCO) thin films on single crystal LaAlO3 substrates were prepared from a trifluoroacetate (TFA) precursor heat treated in a low oxygen partial pressure argon atmosphere. The purpose of the study was to explore the possibility of forming high-purity, epitaxial YBCO films at heat treatment temperatures and oxygen partial pressures low enough to allow the TFA process to be adapted to metallic substrates. The formation of a superconducting YBCO phase was confirmed by measuring the critical temperature (T-c) inductively. In-plane texture and c-axis alignment of the films were determined from x-ray phi scans and omega scans, respectively. Raman microspectroscopy was used to interrogate grain connectivity, oxygen stoichiometry, c-axis verticality with respect to the substrate, and second phase formation. The optimum heat treatment temperature was found to be near 750 degreesC in an argon atmosphere, the equivalent oxygen partial pressure, which was about 10(-5) atm. The full-width half-maxima (FWHMs) of the YBCO (113) phi and (005) omega scans for a sample prepared at 750 degreesC were about 0.6 and 0.5 degrees, respectively, which indicates that the film was epitaxial. This film showed a sharp superconducting transition at 91 K and an inductive critical current density of 1.3 MA cm(-2) at 77 K. The ability to form high-quality YBCO films under the conditions used is consistent with the thermodynamic predictions that the optimal heat treatment temperature decreases as oxygen partial pressure decreases. The results of this study define YBCO formation conditions for TFA-based precursors that may be suitable for application on metallic substrates. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Jee, YA (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Ma, Beihai/I-1674-2013 OI Ma, Beihai/0000-0003-3557-2773 NR 26 TC 33 Z9 35 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD MAY PY 2001 VL 14 IS 5 BP 285 EP 291 DI 10.1088/0953-2048/14/5/308 PG 7 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 437KE UT WOS:000168990200011 ER PT J AU Thompson, JR Paranthaman, M Christen, DK Sorge, KD Kim, HJ Ossandon, JG AF Thompson, JR Paranthaman, M Christen, DK Sorge, KD Kim, HJ Ossandon, JG TI High temporal stability of supercurrents in MgB2 materials SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID SUPERCONDUCTORS; CREEP AB Fine grained polycrystalline samples of MgB2 superconductor were synthesized from the elements to contain < 5 % of impurity phases, according to x-ray powder diffractometry. The superconductive transition was sharp with a midpoint T-c = 38.5 K. The magnetization in the vortex state was studied as a function of applied field H, temperature T and time t. From the equilibrium magnetization, the London penetration depth was obtained. The supercurrent density J(T, H, t) in the vortex state (derived from the irreversible magnetization) decreases approximately linearly with T, in contrast to the quasi-exponential fall-off in high-T-c superconductors. The current is highly stable in time, with normalized decay rates S = - d ln(J)/d ln(t) well below those in high-T-c materials. These results are compared with those of other superconductors. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37837 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Univ Talca, Curico, Chile. RP Thompson, JR (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37837 USA. RI Paranthaman, Mariappan/N-3866-2015 OI Paranthaman, Mariappan/0000-0003-3009-8531 NR 12 TC 11 Z9 13 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD MAY PY 2001 VL 14 IS 5 BP L17 EP L20 DI 10.1088/0953-2048/14/5/102 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 437KE UT WOS:000168990200002 ER PT J AU Durakiewicz, T Arko, AJ Joyce, JJ Moore, DP Halas, S AF Durakiewicz, T Arko, AJ Joyce, JJ Moore, DP Halas, S TI Thermal work function shifts for polycrystalline metal surfaces SO SURFACE SCIENCE LA English DT Article DE work function measurements; surface electronic phenomena (work function, surface potential, surface states, etc.); thermionic emission; field emission; electron emission ID TEMPERATURE-DEPENDENCE; ENERGY AB A new approach is presented fnr the calculation of the thermal shifts of the work functions of polycrystalline metal surfaces by including the thermal expansion of the metal into the election density parameter as il ell as Fermi energy. Calculations of d phi /dT as a function of temperature are performed for 74 elements, encompassing a total of 103 cases of various temperature ranges, phases and (in a few cases) orientations. II is shown that for a majority of metals d phi /dT is not a constant over a broad temperature range. Comparison of theoretical and experimental values indicates that the thermal lattice vibrations do not influence d phi :dT significantly. Our results would suggest that the use of a Kelvin probe to measure the thermal variation of phi may be problematic. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. Marie Curie Sklodowska Univ, Inst Phys, PL-20031 Lublin, Poland. RP Durakiewicz, T (reprint author), Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Mailstop K764, Los Alamos, NM 87545 USA. OI Durakiewicz, Tomasz/0000-0002-1980-1874 NR 32 TC 29 Z9 29 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 1 PY 2001 VL 478 IS 1-2 BP 72 EP 82 DI 10.1016/S0039-6028(01)00898-6 PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 425WL UT WOS:000168314600016 ER PT J AU Feibelman, PJ AF Feibelman, PJ TI Accelerated mound decay at adjacent kinks on Cu(111) SO SURFACE SCIENCE LA English DT Letter DE surface diffusion; growth; density functional calculations; copper; vicinal single crystal surfaces ID ABINITIO MOLECULAR-DYNAMICS; ULTRASOFT PSEUDOPOTENTIALS; FORMATION ENERGIES; STEP-FORMATION; METALS; TRANSITION; SIMULATION; DIFFUSION; PT(111) AB Ab initio barriers to concerted downward transport of Cu atoms range from 0.66 to 0.85 eV, when kinks on adjacent Cu(111) terraces are close. The lowest of these permits mound decay to proceed much faster, at 300-340 K, than when terraces are farther apart, and decay is limited by formation of Cu adatoms and their passage over an island-edge "Schwoebel barrier." (C) 2001 Published by Elsevier Science B.V. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM pjfeibe@sandia.gov NR 25 TC 8 Z9 9 U1 0 U2 2 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 MAY 1 PY 2001 VL 478 IS 1-2 BP L349 EP L354 DI 10.1016/S0039-6028(01)00963-3 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 425WL UT WOS:000168314600008 ER PT J AU Tonn, BE Peretz, JH AF Tonn, BE Peretz, JH TI Method for gauging limits to foresight in environmental decision making SO TECHNOLOGICAL FORECASTING AND SOCIAL CHANGE LA English DT Article AB article presents a mathematically-based method for gauging the limits to foresight in environmental decision making. The method will be useful to environmental decision makers for structuring environmental problems that are characterized by potentially crippling amount of uncertainty. The method produces as output a measure of determinateness (i.e., the amount of information) for each key decision variable based on inputs of lower and upper cumulative distribution functions for each variable for periods into the future. A visualization of the outputs is presented that effectively communicates the limits to foresight for key variables in the analysis. How this information can be used to guide decision strategy is illustrated through an example: strategic planning for municipal solid waste reading. (C) 2001 Elsevier Science Inc. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Sch Planning, Knoxville, TN USA. Univ Tennessee, Energy Environm & Resources Ctr, Knoxville, TN USA. RP Tonn, BE (reprint author), Oak Ridge Natl Lab, POB 2008,Bldg 4500N,MS-6207, Oak Ridge, TN 37831 USA. NR 27 TC 3 Z9 3 U1 1 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0040-1625 J9 TECHNOL FORECAST SOC JI Technol. Forecast. Soc. Chang. PD MAY PY 2001 VL 67 IS 1 BP 35 EP 53 DI 10.1016/S0040-1625(99)00082-7 PG 19 WC Business; Planning & Development SC Business & Economics; Public Administration GA 429GM UT WOS:000168507800003 ER PT J AU Graves, TL Mockus, A AF Graves, TL Mockus, A TI Identifying productivity drivers by modeling work units using partial data SO TECHNOMETRICS LA English DT Article DE EM; missing data; software engineering ID SOFTWARE AB We describe a new algorithm for estimating a model for an independent variable that is not directly observed but that represents one set of marginal totals of a sparse nonnegative tao-way table whose other margin and zero pattern are known. The application that inspired the development of this algorithm arises in software engineering. We seek to identify those factors that affect the effort required for a developer to make a change to the software-for instance, to identify difficult areas of the code, measure changes in the code difficulty through time, and evaluate the effectiveness of development tools. Unfortunately, measurements of effort for changes are not available in historical data. We model change effort using a developer's total monthly effort and information about which changes he/she investigated in each month. We illustrate a few specific applications of our tool, demonstrate that the algorithm is an instance of the EM algorithm, and present a simulation study that speaks well of the reliability of the results our algorithm produces. In short, this algorithm allows analysts to quantify the impact of a promising software engineering tool or practice on coding effort. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Bell Labs, Naperville, IL 60566 USA. RP Graves, TL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 24 TC 7 Z9 7 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 2001 VL 43 IS 2 BP 168 EP 179 DI 10.1198/004017001750386288 PG 12 WC Statistics & Probability SC Mathematics GA 423YT UT WOS:000168205900006 ER PT J AU Chen, Z Deng, M Chen, EP AF Chen, Z Deng, M Chen, EP TI Rate-dependent transition from tensile damage to discrete fracture in dynamic brittle failure SO THEORETICAL AND APPLIED FRACTURE MECHANICS LA English DT Article DE rate-dependent bifurcation; damage; localization; fracture AB Based on the work for a combined damage/plasticity model of geologic materials and the bifurcation analysis of material failure, an analytical framework is established to study the rate-dependent transition from continuum damage to discrete fracture in dynamic brittle failure. Because of the simple formulation, a vectorized constitutive model solver can be designed for large-scale computer simulation. A continuum tangent stiffness tenser is invoked for the tensile damage evolution such that the bifurcation analysis can be performed to identify the initiation and orientation of tensile failure. It is shown that the orientation of tensile failure is rate-independent although the limit state is rate-dependent for the rate-dependent tensile damage model. Sample problems are considered to demonstrate the features of the proposed approach. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Missouri, Dept Civil & Environm Engn, Columbia, MO 65211 USA. Sandia Natl Labs, Sci Based Mat Modeling Dept, Livermore, CA 94551 USA. RP Chen, Z (reprint author), Univ Missouri, Dept Civil & Environm Engn, E2509 Engn Bldg E, Columbia, MO 65211 USA. NR 12 TC 6 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8442 J9 THEOR APPL FRACT MEC JI Theor. Appl. Fract. Mech. PD MAY-JUN PY 2001 VL 35 IS 3 BP 229 EP 235 DI 10.1016/S0167-8442(01)00046-5 PG 7 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 444BL UT WOS:000169378000004 ER PT J AU Meigs, LC Beauheim, RL AF Meigs, LC Beauheim, RL TI Tracer tests in a fractured dolomite 1. Experimental design and observed tracer recoveries SO WATER RESOURCES RESEARCH LA English DT Article ID MATRIX DIFFUSION; NONREACTIVE TRACERS; SOLUTE TRANSPORT; ROCK MATRIX; GROUNDWATER; MIGRATION; POROSITY; AQUIFER; WATER; CHALK AB A series of tracer tests has been conducted in a 7-m-thick fractured dolomite at two sites in southeastern New Mexico. The tests were designed to evaluate transport processes, especially matrix diffusion, in fractured, permeable media. Both Single-well injection-withdrawal (SWIW) and multiwell convergent flow (MWCF) tests were conducted. Seventeen different organic tracers (the fluorobenzoic and chlorobenzoic acids) and iodide were used as conservative tracers for the tests. The MWCF tests included repeated tracer injections while pumping the central well at different rates, injection of tracers with different aqueous diffusion coefficients, and injection of tracers' into both the full and partial formation thickness. This paper describes the tracer test sites and aquifer characteristics, the experimental methods, and the trader data produced. The tracer test results provide a high-quality data set for a critical evaluation of the conceptual model for transport. Both the SWIW and MWCF tracer test data showed gradual mass recovery ana breakthrough (or recovery) curve tailing consistent with matrix diffusion. However, the SWIW recovery curves did not display the -1.5 log-log slope expected from a conventional double-porosity medium with a single rate of diffusion. The breakthrough curves from MWCF tests conducted at two different pumping rates showed similar peak heights, which is also not what was expected with a conventional double-porosity model. However, the peak heights were different for two tracers with different aqueous diffusion coefficients that were injected simultaneously in one test, consistent with the effects of matrix diffusion. The complexity of the tracer test results suggests that a simple double-porosity conceptual model for transport iri the Culebra with a single rate of diffusion is overly simplistic. C1 Sandia Natl Labs, Resp Performance & Certificat Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Geohydrol Dept, Albuquerque, NM 87185 USA. RP Beauheim, RL (reprint author), Sandia Natl Labs, Resp Performance & Certificat Dept, POB 5800,MS 1395, Albuquerque, NM 87185 USA. NR 63 TC 48 Z9 50 U1 1 U2 15 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 MAY PY 2001 VL 37 IS 5 BP 1113 EP 1128 DI 10.1029/2000WR900335 PG 16 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 425AP UT WOS:000168266400001 ER PT J AU Haggerty, R Fleming, SW Meigs, LC McKenna, SA AF Haggerty, R Fleming, SW Meigs, LC McKenna, SA TI Tracer tests in a fractured dolomite 2. Analysis of mass transfer in single-well injection-withdrawal tests SO WATER RESOURCES RESEARCH LA English DT Article ID AGGREGATED POROUS-MEDIA; HETEROGENEOUS SORPTION PROCESSES; TRANSFER RATE COEFFICIENTS; PORE-SCALE HETEROGENEITY; SOLUTE TRANSPORT; HYDRAULIC CONDUCTIVITY; SUBSURFACE SYSTEMS; ORGANIC-CHEMICALS; VOLATILE ORGANICS; SURFACE-REACTIONS AB We investigated multiple-rate diffusion as a possible explanation for observed behavior in a suite of single-well injection-withdrawal (SWIW) tests conducted in a fractured dolomite. We first investigated the ability of a conventional double-porosity model and a multirate diffusion model to explain the data. This revealed that the multirate diffusion hypothesis/model is consistent with available data and is capable of matching all of the recovery curves. Second, we studied the sensitivity of the SWIW curves to the distribution of diffusion rate coefficients and other parameters. We concluded that the SWIW test is very sensitive to the distribution of rate coefficients but is relatively insensitive to other flow and transport parameters such as advective porosity and dispersivity. Third, we examined the significance of the constant double-log late time slopes (-2.1 to -2.8), which are present in several data sets. The observed late time slopes are significantly different than would be predicted by either conventional double-porosity or single-porosity models and are believed to be a distinctive feature of multirate diffusion. Fourth, we found that the estimated distributions of diffusion rate coefficients are very broad, with the distributions spanning a range of up to 3.6 orders of magnitude. Fifth, when both heterogeneity and solute drift are present, late time behavior similar to multirate mass transfer can occur. Although it is clear that multirate diffusion occurs in the Culebra, the number of orders of magnitude of variability may be overestimated because of the combined effects of drift and heterogeneity. C1 Oregon State Univ, Dept Geosci, Corvallis, OR 97331 USA. Sandia Natl Labs, Geohydrol Dept, Albuquerque, NM USA. RP Haggerty, R (reprint author), Oregon State Univ, Dept Geosci, Corvallis, OR 97331 USA. RI Haggerty, Roy/A-5863-2009 NR 54 TC 93 Z9 93 U1 2 U2 25 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 MAY PY 2001 VL 37 IS 5 BP 1129 EP 1142 DI 10.1029/2000WR900334 PG 14 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 425AP UT WOS:000168266400002 ER PT J AU McKenna, SA Meigs, LC Haggerty, R AF McKenna, SA Meigs, LC Haggerty, R TI Tracer tests in a fractured dolomite 3. Double-porosity, multiple-rate mass transfer processes in convergent flow tracer tests SO WATER RESOURCES RESEARCH LA English DT Article ID PORE-SCALE HETEROGENEITY; EL BERROCAL SITE; RADIAL DISPERSION; SURFACE-REACTIONS; STREAM TRACER; FIELD; AQUIFER; TRANSPORT; MIGRATION; DIFFUSION AB Convergent flow tracer tests conducted in the Culebra dolomite (Rustler Formation, New Mexico) are analyzed with both single- and multiple-rate, double-porosity models. Parameter estimation is used to determine the mean and standard deviation of a lognormal distribution of diffusion rate coefficients as well as the advective porosity and longitudinal dispersivity. At two different test sites both multirate and single-rate models are capable of accurately modeling the observed data. The single-well injection-withdrawal test provides more precise estimates of the mass transfer parameters than the convergent flow trace; tests. Estimation of the multirate distribution parameters is consistent across locations for the two types of tests. Limits of resolution are calculated for the multirate distribution, and these limits explain the precision with which the standard deviation of the multirate distribution can be estimated. These limits also explain the necessary increase in the advective porosity for the single-rate model at one location and not the other. Implications of the multirate mass transfer model at lime and length scales greater than those of the tracer tests include the instantaneous equilibrium of a significant fraction of the matrix and the possibility of a fraction of the diffusive porosity not reaching an equilibrium solute concentration at long times. C1 Sandia Natl Labs, Geohydrol Dept, Albuquerque, NM 87185 USA. Oregon State Univ, Dept Geosci, Corvallis, OR 97331 USA. RP McKenna, SA (reprint author), Sandia Natl Labs, Geohydrol Dept, POB 5800,MS 0735, Albuquerque, NM 87185 USA. RI Haggerty, Roy/A-5863-2009 NR 25 TC 61 Z9 61 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 MAY PY 2001 VL 37 IS 5 BP 1143 EP 1154 DI 10.1029/2000WR900333 PG 12 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 425AP UT WOS:000168266400003 ER PT J AU Wan, JM Veerapaneni, S Gadelle, F Tokunaga, TK AF Wan, JM Veerapaneni, S Gadelle, F Tokunaga, TK TI Generation of stable microbubbles and their transport through porous media SO WATER RESOURCES RESEARCH LA English DT Article ID STABILIZED MICROBUBBLES; CONTRAST AGENT; MICROORGANISMS; GROUNDWATER; FILTRATION; ULTRASOUND; WATER AB Laboratory experiments were conducted to generate stable microbubbles and to measure their transport properties in porous media in order to evaluate their possible use in subsurface remediation. A mathematic model was developed as a special case of filtration theory for predicting microbubble transport in porous media. Several physical-chemical parameters were tested, including surfactant type, surfactant concentration, generation method, and pressure. A combination of an anionic surfactant and a hydrophobic nonionic surfactant was found to yield the highest concentrations of stable microbubbles (3 X 10(9) bubbles mL(-1)) in the size range or 0.7 to 20 mum. he specific surface areas of the microbubble suspensions were in the range of 50 cm(2) mL(-1), and specific air volumes were >0.07 mL mL(-1). For 1 pore volume of injected bubble suspension, effluent recoveries of 100, 80, and 30% were achieved from columns of coarse (415-500 mum), medium (150-212 mum), and fine (53-106 mum) sands, respectively. Effluent recovery in the fine sand column increased to 63% following a 3 pore volume injection. Microbubble generation and injection under pressure were shown to minimize microbubble loss due to gas dissolution. Results from the modeling suggest that retention of microbubbles could be adequately described by filtration theory. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Wan, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, MS 90-1116, Berkeley, CA 94720 USA. RI Tokunaga, Tetsu/H-2790-2014; Wan, Jiamin/H-6656-2014 OI Tokunaga, Tetsu/0000-0003-0861-6128; NR 22 TC 14 Z9 15 U1 0 U2 18 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 MAY PY 2001 VL 37 IS 5 BP 1173 EP 1182 DI 10.1029/2000WR900331 PG 10 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 425AP UT WOS:000168266400006 ER PT J AU Glass, RJ Conrad, SH Yarrington, L AF Glass, RJ Conrad, SH Yarrington, L TI Gravity-destabilized nonwetting phase invasion in macroheterogeneous porous media: Near-pore-scale macro modified invasion percolation simulation of experiments SO WATER RESOURCES RESEARCH LA English DT Article ID CAPILLARY-PRESSURE; MODEL; NETWORK AB We reconceptualize "macro" modified invasion percolation (MMIP) at the near pore (NP) scale and apply it to simulate the nonwetting phase invasion experiments of Glass et al. [2000] conducted in macroheterogeneous porous media. For experiments where viscous forces were nonnegligible, we redefine the total pore filling pressure to include viscous losses within the invading phase as well as the viscous influence to decrease randomness imposed by capillary forces at the front. NP MMIP exhibits the complex invasion order seen experimentally with characteristic alternations between periods of gravity-stabilized and destabilized invasion growth controlled by capillary barriers. The breaching of these barriers and subsequent pore-scale fingering of the nonwetting phase is represented extremely well, as is the saturation field evolution and total volume invaded. C1 Sandia Natl Labs, Flow Visualisat & Proc Lab, Albuquerque, NM 87185 USA. RP Glass, RJ (reprint author), Sandia Natl Labs, Flow Visualisat & Proc Lab, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 27 Z9 27 U1 0 U2 4 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 MAY PY 2001 VL 37 IS 5 BP 1197 EP 1207 DI 10.1029/2000WR900294 PG 11 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 425AP UT WOS:000168266400008 ER PT J AU Assouline, S Tartakovsky, DM AF Assouline, S Tartakovsky, DM TI Unsaturated hydraulic conductivity function based on a soil fragmentation process SO WATER RESOURCES RESEARCH LA English DT Article ID PORE-SIZE DISTRIBUTIONS; WATER-RETENTION CURVE; PARTICLE; EQUATION; MODEL AB We present a new two-parameter expression for relative hydraulic conductivity (RHC) of partially saturated soils. It is based on the premise of Assouline et al. [1998] that soil structures evolve from a uniform random fragmentation process. This assumption allows us to derive hydraulic properties of soils (water retention curves and unsaturated hydraulic conductivity) from primary properties, such as pore geometry and soil structure. We tested our RHC expression against different soil types and found that it fits data better than the widely used models of Brooks and Corey [1964] and van Genuchten [1980]. C1 Agr Res Org, Volcani Ctr, Inst Soil Water & Environm Sci, Dept Environm Phys, IL-50250 Bet Dagan, Israel. Univ Calif Los Alamos Natl Lab, Math Modeling & Anal Grp, Los Alamos, NM 87545 USA. RP Assouline, S (reprint author), Agr Res Org, Volcani Ctr, Inst Soil Water & Environm Sci, Dept Environm Phys, IL-50250 Bet Dagan, Israel. RI Tartakovsky, Daniel/E-7694-2013 NR 15 TC 16 Z9 16 U1 1 U2 5 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 MAY PY 2001 VL 37 IS 5 BP 1309 EP 1312 DI 10.1029/2000WR900332 PG 4 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 425AP UT WOS:000168266400017 ER PT J AU Prasad, R Tarboton, DG Liston, GE Luce, CH Seyfried, MS AF Prasad, R Tarboton, DG Liston, GE Luce, CH Seyfried, MS TI Testing a blowing snow model against distributed snow measurements at Upper Sheep Creek, Idaho, United States of America SO WATER RESOURCES RESEARCH LA English DT Article ID COMPLEX TERRAIN; SYSTEM AB In this paper a physically based snow transport model (SnowTran-3D) was used to simulate snow drifting over a 30 m grid and was compared to detailed snow water equivalence (SWE) surveys on three dates within a small 0.25 km(2) subwatershed, Upper Sheep Creek. Two precipitation scenarios and two vegetation scenarios were used to carry out four snow transport model runs in order to (1) evaluate the blowing snow model, (2) evaluate the sensitivity of the snow transport model to precipitation and vegetation inputs, and (3) evaluate the linearity of snow accumulation patterns and the utility of the drift factor concept in distributed snow modeling. Spatial comparison methods consisted of (1) pointwise comparisons of measured and modeled SWE, (2) visual comparisons of the spatial maps, (3) comparisons of the basin-wide average SWE, (4) comparisons of zonal average SWE in accumulation and scour zones, and (5) comparisons of distribution functions. We found that the basin average modeled SWE was in reasonable agreement with observations and that visually the spatial pattern of snow accumulation was well represented except for a pattern shift. Pointwise comparisons between the modeled and observed SWE maps displayed significant errors. The distribution functions of SnowTran-3D-modeled drift factors from two precipitation scenarios on three dates were compared with the distribution function of observation-based drift factors obtained previously by calibration to evaluate the assumption of linearity. We found only a 14% reduction in explained variance in the distribution function of drift factors for a 69% increase in precipitation, suggesting that the simplification provided by the use of drift factor distributions will result in errors that are tolerable in many cases. C1 Utah State Univ, Dept Civil & Environm Engn, Logan, UT 84322 USA. USDA ARS, NW Watershed Res Ctr, Boise, ID 83712 USA. Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. US Forest Serv, USDA, Boise, ID USA. USDA ARS, NW Watershed Res Ctr, Boise, ID 83712 USA. RP Prasad, R (reprint author), Pacific NW Natl Lab, POB 999,MSIN K9-33, Richland, WA 99352 USA. RI Luce, Charles/A-9267-2008; Tarboton, David/G-8972-2011 OI Luce, Charles/0000-0002-6938-9662; Tarboton, David/0000-0002-1998-3479 NR 38 TC 39 Z9 39 U1 0 U2 7 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 MAY PY 2001 VL 37 IS 5 BP 1341 EP 1356 DI 10.1029/2000WR900317 PG 16 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 425AP UT WOS:000168266400020 ER PT J AU Smith, RD Benson, DK Maroef, I Olson, DL Wildeman, TR AF Smith, RD Benson, DK Maroef, I Olson, DL Wildeman, TR TI The determination of hydrogen distribution in high-strength steel weldments Part 2: Opto-electronic diffusible hydrogen sensor SO WELDING JOURNAL LA English DT Article AB In Part 1, methods for measurement of hydrogen. distributions in high-strength welded-steel using laser ablation were described. Part 2 will elaborate on an advanced design for a diffusible hydrogen sensor that utilizes the optoelectronic properties of a hydrogen-sensitive material such as tungsten (VI) oxide, WO3. The sensor generates the necessary analytical signal in less than one hour and has been calibrated to yield results in mL/100 g weld metal. The sensor is extremely sensitive to hydrogen and relatively inexpensive. An array of sensors could conceivably be used to measure diffusible hydrogen distributions across the weld face with a resolution of approximately one millimeter. The sensor shows excellent promise as an advanced hydrogen measurement technique, and research is continuing to establish procedures for transfer to industry. C1 DCH Technol, Valencia, CA USA. Natl Renewable Energy Lab, Golden, CO USA. Colorado Sch Mines, Ctr Welding Joining & Coatings Res, Golden, CO 80401 USA. RP Smith, RD (reprint author), DCH Technol, Valencia, CA USA. NR 10 TC 1 Z9 1 U1 2 U2 2 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 MAY PY 2001 VL 80 IS 5 BP 122S EP 125S PG 4 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 746KU UT WOS:000186746200017 ER PT J AU Kim, SK Kortright, JB Shin, SC AF Kim, SK Kortright, JB Shin, SC TI Vector magnetization imaging in ferromagnetic thin films using soft x-rays SO APPLIED PHYSICS LETTERS LA English DT Article ID ELECTRON-MICROSCOPY; CIRCULAR-DICHROISM; CO FILMS; EXCHANGE; MICROSTRUCTURE; PERMALLOY; DOMAINS; WALLS AB A magnetization vector M imaging using a transmission x-ray microscope with magnetic circular dichroism (MCD) contrast is demonstrated. MCD images through a semitransparent, 33-nm-thick Fe film are measured at the Fe L(3) edge along three different x-ray propagation directions to determine all three components of the M. The transmission images clearly display the vector nature of complex microstructures, associated with the M reversal between oppositely oriented 180 degrees domains, including not only 90 degrees domains, a Neel wall-like structure, and an extended ripple structure, but also a striking feature of localized magnetization spirals with perpendicular components at their cores. These studies have important implications for applications of this technique to better understand the expected features as well as details of domain-wall structures. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Korea Adv Inst Sci & Technol, Dept Phys, Taejon 305701, South Korea. Korea Adv Inst Sci & Technol, Ctr Nanospin Spintron Mat, Taejon 305701, South Korea. RP Kim, SK (reprint author), Korea Adv Inst Sci & Technol, Dept Phys, Taejon 305701, South Korea. EM sangkoog@kaist.ac.kr; JBKortright@lbl.gov RI Shin, Sung-Chul/C-1992-2011; Kim, Sang-Koog/J-4638-2014 NR 25 TC 25 Z9 25 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 30 PY 2001 VL 78 IS 18 BP 2742 EP 2744 DI 10.1063/1.1370120 PG 3 WC Physics, Applied SC Physics GA 425RD UT WOS:000168304700043 ER PT J AU Han, WQ Cumings, J Zettl, A AF Han, WQ Cumings, J Zettl, A TI Pyrolytically grown arrays of highly aligned BxCyNz nanotubes SO APPLIED PHYSICS LETTERS LA English DT Article ID B-C-N; BORON-NITRIDE NANOTUBES; CARBON NANOTUBES; GRAPHITIC CARBON; PYROLYSIS; NANOSTRUCTURES; NANOFIBERS AB A pyrolysis route has been used to synthesize arrays of highly aligned BxCyNz nanotubes in bulk. The structure and composition of the product were characterized by scanning electron microscopy, high-resolution transmission electron microscopy, and electron energy-loss spectroscopy. The length and diameter of the nanotubes are quite uniform in a large area of the reaction zone. The sizes of the aligned BxCyNz nanotubes from the whole reaction zone are 10-30 mum in length and 20-140 nm in diameter. The x/z ratio of BxCyNz nanotubes for most nanotubes is about 1:1. The x/y ratio of BxCyNz nanotubes is up to 0.6. Within one nanotube, the x/y ratio is usually heterogeneous. The growth mechanism is also discussed. (C) 2001 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 Cumings, John/A-3595-2012; Han, WQ/E-2818-2013; Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 21 TC 29 Z9 29 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 30 PY 2001 VL 78 IS 18 BP 2769 EP 2771 DI 10.1063/1.1369620 PG 3 WC Physics, Applied SC Physics GA 425RD UT WOS:000168304700052 ER PT J AU Demczyk, BG Cumings, J Zettl, A Ritchie, RO AF Demczyk, BG Cumings, J Zettl, A Ritchie, RO TI Structure of boron nitride nanotubules SO APPLIED PHYSICS LETTERS LA English DT Article ID CARBON NANOTUBES; LASER-ABLATION AB We have used high-resolution transmission electron microscopy to resolve the [0001] projected basal plane structure and chirality relationships in boron nitride nanotubes. Evidence for tube growth along both < 10 (1) over bar0 > and < 11 (2) over bar0 > is found. Our results suggest that the < 11 (2) over bar0 > (armchair) tubes form first. Subsequent growth can take the form of a < 10 (1) over bar0 > (zig-zag) tube or additional armchair tubes. In both cases, the additional walls can be accommodated without the need for defect formation for circumferential tube closure. These results suggest that real boron nitride tubes may, in practice, realize their inherently high modulus and display less variation of mechanical properties than tubes comprised of carbon. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Demczyk, BG (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Cumings, John/A-3595-2012; Ritchie, Robert/A-8066-2008; Zettl, Alex/O-4925-2016 OI Ritchie, Robert/0000-0002-0501-6998; Zettl, Alex/0000-0001-6330-136X NR 21 TC 58 Z9 59 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 30 PY 2001 VL 78 IS 18 BP 2772 EP 2774 DI 10.1063/1.1367906 PG 3 WC Physics, Applied SC Physics GA 425RD UT WOS:000168304700053 ER PT J AU Kercher, JR Chambers, JQ AF Kercher, JR Chambers, JQ TI Parameter estimation for a global model of terrestrial biogeochemical cycling by an iterative method SO ECOLOGICAL MODELLING LA English DT Review DE net primary production; carbon cycle; nitrogen cycle; water balance; evapotranspiration; model calibration ID FOREST ECOSYSTEM PROCESSES; NET PRIMARY PRODUCTIVITY; ATMOSPHERIC CO2; ORGANIC-MATTER; CARBON-CYCLE; BIOSPHERE MODEL; SOIL-WATER; REGIONAL APPLICATIONS; SHORTGRASS PRAIRIE; LICHEN WOODLAND AB We have implemented a geographically distributed ecosystem model TERRA for the carbon, nitrogen, and water dynamics of the global terrestrial biosphere. The ecosystem model in each grid cell has state variables of soil water; vegetation carbon, soil carbon, vegetation nitrogen, soil organic nitrogen, soil inorganic nitrogen, and a variable for allocation. Eight parameters associated with eight carbon or nitrogen fluxes are determined during model calibration at specific sites for each of 17 vegetation types that cover the globe. Calibration is performed by an iterative method that brings calculated fluxes into agreement with observed fluxes over successive iterations. For the 17 vegetation types, calibration required a geometric mean number of 123 iterations for convergence with a geometric S.D. of 2.25. The minimum and maximum iterations required was 52 and 1060 for xeromorphic woodland and tropical evergreen forest, respectively. The parameter controlling gross primary productivity C-max was found to be correlated with maximum projected leaf area index (plus cover of nonvascular plants) with a correlation coefficient of 0.90 (r(2) = 0.81). Correlation of parameters with the input fluxes and average standing crops corresponding to the iteration equation was high in those cases in which temperature and precipitation were not explicit factors in the iteration equation. The parameters K-fall, L-nc, and N-loss had correlation coefficients of 1.0 each with the appropriate ratio of the matching observed transfer flux and standing crop. In iteration equations with explicit dependence on temperature, soil moisture, and other factors, the correlation coefficients were less than 1.0 with these ratios; the parameters C-max, K-r, K-d, N-max, and N-up had correlation coefficients of 0.83, 0.66, 0.60, 0.61, and 0.87, respectively. These correlation coefficients indicate the importance of environmental factors such as temperature and soil moisture in the calibration process and the robustness of the iteration method in determining parameters in systems with time-varying coefficients. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, Livermore, CA 94551 USA. Lawrence Livermore Natl Lab, Div Atmospher Sci, Livermore, CA 94550 USA. Univ Calif Santa Barbara, Dept Biol Sci, Santa Barbara, CA 93106 USA. RP Kercher, JR (reprint author), Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, POB 808,L-286, Livermore, CA 94551 USA. EM jkercher@llnl.gov RI Chambers, Jeffrey/J-9021-2014 OI Chambers, Jeffrey/0000-0003-3983-7847 NR 148 TC 12 Z9 14 U1 3 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3800 J9 ECOL MODEL JI Ecol. Model. PD APR 30 PY 2001 VL 139 IS 2-3 BP 137 EP 175 DI 10.1016/S0304-3800(01)00234-4 PG 39 WC Ecology SC Environmental Sciences & Ecology GA 438XV UT WOS:000169080300003 ER PT J AU Tautges, TJ AF Tautges, TJ TI The generation of hexahedral meshes for assembly geometry: survey and progress SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE mesh generation; hexahedral; quadrilateral; geometry decomposition ID MEDIAL SURFACE SUBDIVISION; FINITE-ELEMENT; ALGORITHM; SOLIDS; MORPH; EDGES; VOLUMES AB The finite element method is being used today to model component assemblies in a wide variety of application areas, including structural mechanics, fluid simulations, and others. Generating hexahedral meshes for these assemblies usually requires the use of geometry decomposition, with different meshing algorithms applied to different regions. While the primary motivation for this approach remains the lack of an automatic, reliable all-hexahedral meshing algorithm, requirements in mesh quality and mesh configuration for typical analyses are also factors. For these reasons, this approach is also sometimes required when producing other types of unstructured meshes. This paper will review progress to date in automating many parts of the hex meshing process, which has halved the time to produce all-hex meshes for large assemblies. Particular issues which have been exposed due to this progress will also be discussed, along with their applicability to the general unstructured meshing problem. Published in 2001 by John Wiley & Sons, Ltd. C1 Univ Wisconsin, Sandia Corp, Sandia Natl Labs, Madison, WI 53706 USA. RP Tautges, TJ (reprint author), Univ Wisconsin, Sandia Corp, Sandia Natl Labs, 1500 Engn Dr, Madison, WI 53706 USA. NR 70 TC 37 Z9 41 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD APR 30 PY 2001 VL 50 IS 12 BP 2617 EP 2642 DI 10.1002/nme.139 PG 26 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 419VZ UT WOS:000167970600002 ER PT J AU Faulon, JL AF Faulon, JL TI Stochastic generator of chemical structure. 4. Building polymeric systems with specified properties SO JOURNAL OF COMPUTATIONAL CHEMISTRY LA English DT Article DE polymer; crosslink; network; structure builder ID MOLECULAR-DYNAMICS SIMULATION; MACROMOLECULAR SYSTEMS; COMPUTER-SIMULATION; MELTS; NETWORKS; MODEL; ENTANGLEMENTS; POLYSTYRENE; LATTICE; CHAINS AB A novel computational technique to generate close-to-equilibrium crosslinked polymeric systems is proposed. Compared to the current state-of-the-art equilibration methods, the new technique appears to be faster by several orders of magnitude. The main advantage of the technique is that one can circumvent the bottlenecks in configuration space that inhibit relaxation in molecular dynamics or Monte Carlo simulations. The problem of polymer equilibration described by continuous equations in molecular dynamics is reduced to a discrete representation where solutions are approximated by simple algorithms. In the current study, a series of coarse-grained, united-atom, and fully atomistic crosslinked networks has been generated. Network statistics and topology, X-ray scattering intensities, and elastic properties are tested vs. experimental results and similar models generated using molecular dynamics and Monte Carlo simulations. The results demonstrate the efficiency of this new method for generating large realistic polymeric systems up to 1.4 M atoms. (C) 2001 John Wiley & Sons, Inc. C1 Sandia Natl Labs, Computat Biol & Mat Technol Dept, Livermore, CA 94551 USA. RP Faulon, JL (reprint author), Sandia Natl Labs, Computat Biol & Mat Technol Dept, Livermore, CA 94551 USA. NR 27 TC 9 Z9 9 U1 3 U2 6 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0192-8651 J9 J COMPUT CHEM JI J. Comput. Chem. PD APR 30 PY 2001 VL 22 IS 6 BP 580 EP 590 DI 10.1002/jcc.1030 PG 11 WC Chemistry, Multidisciplinary SC Chemistry GA 418FC UT WOS:000167879400002 ER PT J AU Smith, DY Inokutil, M Karstens, W AF Smith, DY Inokutil, M Karstens, W TI A generalized Cauchy dispersion formula and the refractivity of elemental semiconductors SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID INDEX; SILICON AB A generalized Cauchy dispersion formula applicable to both normal and anomalous dispersion in the refractive index of transparent materials is derived from the Kramers-Kronig relations. Several commonly used dispersion formulae are closely related to this result. The expansion coefficients, heretofore considered empirical, are simply the odd moments of the absorption spectrum. These ideas are illustrated for natural diamond, and high-purity silicon and germanium. Analysis of published data for these materials discloses extrinsic dispersive effects in the far infrared, even for 'high-purity' samples. We attribute this dispersion to free-carrier or defect-induced absorptions at energies below the range of measurements. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Vermont, Dept Phys, Burlington, VT 05405 USA. St Michaels Coll, Dept Phys, Colchester, VT 05439 USA. RP Smith, DY (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 36 TC 34 Z9 35 U1 3 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 APR 30 PY 2001 VL 13 IS 17 BP 3883 EP 3893 DI 10.1088/0953-8984/13/17/309 PG 11 WC Physics, Condensed Matter SC Physics GA 431JY UT WOS:000168629100012 ER PT J AU Petrovic, C Pagliuso, PG Hundley, MF Movshovich, R Sarrao, JL Thompson, JD Fisk, Z Monthoux, P AF Petrovic, C Pagliuso, PG Hundley, MF Movshovich, R Sarrao, JL Thompson, JD Fisk, Z Monthoux, P TI Heavy-fermion superconductivity in CeCoIn5 at 2.3 K SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter ID WAVE SUPERCONDUCTIVITY; SPIN FLUCTUATIONS; P-WAVE; CECU2SI2; CERHIN5; METALS AB We report the observation of heavy-fermion superconductivity in CeCoIn5 at T-c = 2.3 K. When compared to the pressure-induced T-c of its cubic relative CeIn3 (T-c similar to 200 mK), the T-c of CeCoIn5 is remarkably high. We suggest that this difference may arise from magnetically mediated superconductivity in the layered crystal structure of CeCoIn5. C1 Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Cambridge, Cavendish Lab, Cambridge CB3 OHE, England. RP Petrovic, C (reprint author), Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RI Petrovic, Cedomir/A-8789-2009; Pagliuso, Pascoal/C-9169-2012 OI Petrovic, Cedomir/0000-0001-6063-1881; NR 23 TC 605 Z9 606 U1 14 U2 144 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 APR 30 PY 2001 VL 13 IS 17 BP L337 EP L342 DI 10.1088/0953-8984/13/17/103 PG 6 WC Physics, Condensed Matter SC Physics GA 431JY UT WOS:000168629100003 ER PT J AU Duncan, AP Mullins, SM Arnold, J Bergman, RG AF Duncan, AP Mullins, SM Arnold, J Bergman, RG TI Synthesis, structural investigation, and reactivity of neutral and cationic bis(guanidinato)zirconium(IV) complexes SO ORGANOMETALLICS LA English DT Article ID M = ZR; OLEFIN POLYMERIZATION CATALYSTS; DIANIONIC GUANIDINATE LIGANDS; ZIRCONIUM BENZYL COMPLEXES; ETHYLENE POLYMERIZATION; CRYSTAL-STRUCTURES; ALKYLZIRCONIUM COMPLEXES; MOLECULAR-STRUCTURE; ANCILLARY LIGANDS; ALKYL COMPLEXES AB The mono(guanidinato) complex Cp(guan)ZrCl2 (1; guan = eta (2)-((PrN)-Pr-i)(2)C(NMe2)) was prepared by treatment of CpZrCl3 (Cp = eta (5)-C5H5) with the in situ generated lithium guanidinate salt 2. The dimethylamino group of 1 resists quaternization by alkylating and silylating reagents. Complex 1 undergoes ligand redistribution when treated with 2 equiv of MeLi, but reaction with 2 equiv of MeMgCl affords the dimethyl derivative Cp(guan)ZrMe2 (3). Insertion of 3 equiv of diisopropylcarbodiimide into the Zr-N bonds of (Me2N)(2)ZrCl2(THF)(2) produces the bis(guanidinato)zirconium dichloride complex (guan)(2)ZrCl2 (ii). Alkylation of 4 with 2 equiv of MeLi or PhCH2MgCl affords the dialkyl derivatives (guan)(2)ZrMe2 (5) and (guan)(2)Zr(CH2-Ph)(2) (6), respectively. Variable-temperature NMR experiments on 6 reveal a limiting C-2-symmetric solution structure at 253 K. Complex 5 undergoes reaction with electrophiles (Me3SiOTf (OTf = OSO2CF3), B(C6F5)(3), [Ph3C][B(C6F5)(4)]) to yield stable products of methide abstraction: neutral complexes (guan)(2)Zr(OTf)(2) (7) and (guan)(2)Zr(Me)OTf (8), base-free cationic alkyl salts [(guan)(2)ZrMe][MeB(C6F5)(3)] (9) and [(guan)(2)ZrMe][B(C6F5)(4)] (10), and the dinuclear methyl-bridged cation [((guan)(2)ZrMe)(2)-mu -Me][B(C6F5)(4)] (11). Complexes 1, 4-7, and 11 have been characterized by X-ray diffraction. Dinuclear cation 11 exhibits bridge-terminal methyl exchange on the NMR time scale at room temperature, with decoalescence observed at 224 Ii. Dibenzyl complex 6 undergoes reaction with [Ph3C][B(C6F5)(4)] in CH2Cl2, yielding the cationic benzyl complex [(guan)(2)Zr(CH2Ph)][B(C6F5)(4)] (15). Spectroscopic data imply that the benzyl ligand of 15 adopts an undistorted monodentate coordination mode. Complexes 4, 5, and 10 were found to have low to moderate activities for the polymerization of alpha -olefins. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, CNDOS, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Arnold, John/F-3963-2012 OI Arnold, John/0000-0001-9671-227X NR 88 TC 100 Z9 101 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 APR 30 PY 2001 VL 20 IS 9 BP 1808 EP 1819 DI 10.1021/om000995u PG 12 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 428DK UT WOS:000168445800013 ER PT J AU Berning, DE Miedaner, A Curtis, CJ Noll, BC DuBois, MCR Dubois, DL AF Berning, DE Miedaner, A Curtis, CJ Noll, BC DuBois, MCR Dubois, DL TI Free-energy relationships between the proton and hydride donor abilities of [HNi(diphosphine)(2)](+) complexes and the half-wave potentials of their conjugate bases SO ORGANOMETALLICS LA English DT Article ID TRANSITION-METAL COMPLEXES; BOND-DISSOCIATION ENERGIES; THERMODYNAMIC ACIDITY; DIHYDROGEN COMPLEXES; ELECTRODE-POTENTIALS; LIGAND; STABILIZATION; DECOMPOSITION; NICKEL(II); PARAMETERS AB A linear free-energy relationship exists between the half-wave potentials of the (II/I) couples of Ni(diphosphine)(2) complexes and the hydride donor ability (DeltaG(H)(o)(-)) of the corresponding [HNi(diphosphine)(2)](+) complexes. A similar correlation is observed between the half-wave potentials of the (I/O) couples of Ni(diphosphine)(2) complexes and the pK(a) values (or DeltaG(H)(o)(+)) of the corresponding [HNi(diphosphine)(2)](+) complexes. As a result, it is possible to use the potentials of these two couples to predict the free energies of all three Ni-H bond cleavage reactions, DeltaG(H)(o)(+), DeltaG(H)(o)(.), and DeltaG(H)(o)(-), for this class of nickel complexes. The molecular structures of Ni(Et2PCH2CH2PPh2)(2) and Ni(Ph2PCHCHPPh2)(2) were determined by single-crystal Ii-ray diffraction studies. C1 Natl Renewable Energy Lab, Golden, CO USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Dubois, DL (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO USA. NR 41 TC 75 Z9 75 U1 2 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD APR 30 PY 2001 VL 20 IS 9 BP 1832 EP 1839 DI 10.1021/om0100582 PG 8 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 428DK UT WOS:000168445800016 ER PT J AU Kuzmich, A Dogariu, A Wang, LJ Milonni, PW Chiao, RY AF Kuzmich, A Dogariu, A Wang, LJ Milonni, PW Chiao, RY TI Signal velocity, causality, and quantum noise in superluminal light pulse propagation SO PHYSICAL REVIEW LETTERS LA English DT Article ID AMPLIFIERS; ALWAYS; CANNOT AB We consider pulse propagation in a linear anomalously dispersive medium where the group velocity exceeds the speed of light in vacuum (c) or even becomes negative. A signal velocity is defined operationally based on the optical signal-to-noise ratio, and is computed for cases appropriate to the recent experiment where such a negative group velocity was observed. It is found that quantum fluctuations limit the signal velocity to values less than c. C1 NEC Res Inst, Princeton, NJ 08540 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP NEC Res Inst, 4 Independence Way, Princeton, NJ 08540 USA. RI Wang, Bo/K-7928-2012 NR 18 TC 148 Z9 155 U1 1 U2 20 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 APR 30 PY 2001 VL 86 IS 18 BP 3925 EP 3929 DI 10.1103/PhysRevLett.86.3925 PG 5 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900001 PM 11328062 ER PT J AU Son, DT Stephanov, MA Zhitnitsky, AR AF Son, DT Stephanov, MA Zhitnitsky, AR TI Domain walls of high-density QCD SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLOR-FLAVOR-LOCKING; INSTANTONS; SUPERCONDUCTIVITY; MASSES; MATTER; PHASE AB We show that in very dense quark matter there must exist metastable domain walls where the axial U(1) phase of the color-superconducting condensate changes by 2 pi. The decay rate of the domain walls is exponentially suppressed and we compute it semiclassically. We give an estimate of the critical chemical potential above which our analysis is under theoretical control. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. RP Son, DT (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. NR 25 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 APR 30 PY 2001 VL 86 IS 18 BP 3955 EP 3958 DI 10.1103/PhysRevLett.86.3955 PG 4 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900008 PM 11328069 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, S Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Cassada, J 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, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gordon, A Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K 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, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, J Lancaster, M Lander, R Latino, C LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Okmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Safonov, A Denis, RS Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T 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 Taylor, W Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, MJ Watanabe, T Waters, D Watts, T Webb, R 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 Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, S Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Cassada, J 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, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gordon, A Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K 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, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, J Lancaster, M Lander, R Latino, C LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Okmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Safonov, A Denis, RS Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T 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 Taylor, W Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, MJ Watanabe, T Waters, D Watts, T Webb, R 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 Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Production of chi(c1) and chi(c2) in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID OCTET QUARKONIA PRODUCTION; HADRONIC PRODUCTION; FERMILAB-TEVATRON; HEAVY QUARKONIA; CHARMONIUM; J/PSI; STATES; HADROPRODUCTION; POLARIZATION; DETECTOR AB We have measured the ratio of prompt production rates of the charmonium states chi (c1) and chi (c2) in 110 pb(-1) of p (p) over bar collisions at roots = 1.8 TeV. The photon from their decay into J/Psi gamma is reconstructed through conversion into ece pairs. The energy resolution this technique provides makes the resolution of the two states possible. We find the ratio of production cross sections sigma chi (c1)/sigma chi (c1) = 0.96 +/- 0.27(stat) +/- 0.11(syst) for events with p(T)(J/Psi) > 4.0 GeV/c, /eta (J/Psi)/ < 0.6, and p(T)(gamma) > 1.0 GeV/c. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 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. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Harvard Univ, Cambridge, MA 02138 USA. 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. High Energy Accelerator Res Org, KEK, Tsukuba, Ibaraki 305, Japan. MIT, Cambridge, MA 02139 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 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 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 Affolder, T (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Prokoshin, Fedor/E-2795-2012; Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; Gorelov, Igor/J-9010-2015 OI Prokoshin, Fedor/0000-0001-6389-5399; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Gorelov, Igor/0000-0001-5570-0133 NR 25 TC 25 Z9 25 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 30 PY 2001 VL 86 IS 18 BP 3963 EP 3968 DI 10.1103/PhysRevLett.86.3963 PG 6 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900010 PM 11328071 ER PT J AU Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GF Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, C James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B Magnin, J MayTal-Beck, S Meadows, B Neto, JRTD Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C AF Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GF Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, C James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B Magnin, J MayTal-Beck, S Meadows, B Neto, JRTD Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C CA Fermilab E791 Collaboration TI Search for rare and forbidden charm meson decays D-0 -> Vl(+)l(-) and hhll SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHYSICS; SYSTEM; LIMITS AB We report results of a search for flavor-changing neutral current (FCNC), lepton flavor, and lepton number violating decays of the D-0 (and its antiparticle) into three and four bodies. Using data from Fermilab charm hadroproduction experiment E791, we examine modes with two leptons (muons or electrons) and a rho (0), (K) over bar (*0) or phi vector meson or a nonresonant pi pi, K pi, or KK pair of pseudoscalar mesons. No evidence for any of these decays is found. Therefore, we present branching-fraction upper limits at 90% confidence level for the 27 decay modes examined(18 new). C1 Univ Mississippi Oxford, University, MS 38677 USA. Ctr Brasileiro Pesquisas Fis, BR-22290 Rio De Janeiro, Brazil. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. CINVESTAV, Mexico City 07000, DF, Mexico. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. IIT, Chicago, IL 60616 USA. Kansas State Univ, Manhattan, KS 66506 USA. Univ Massachusetts, Amherst, MA 01003 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Autonoma Puebla, Puebla 72570, Mexico. Univ S Carolina, Columbia, SC 29208 USA. Stanford Univ, Stanford, CA 94305 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Tufts Univ, Medford, MA 02155 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. RP Aitala, EM (reprint author), Univ Mississippi Oxford, University, MS 38677 USA. RI Anjos, Joao/C-8335-2013; Santoro, Alberto/E-7932-2014; Gobel Burlamaqui de Mello, Carla /H-4721-2016; Fernandez Tellez, Arturo/E-9700-2017 OI Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X; Fernandez Tellez, Arturo/0000-0003-0152-4220 NR 27 TC 17 Z9 17 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 30 PY 2001 VL 86 IS 18 BP 3969 EP 3972 DI 10.1103/PhysRevLett.86.3969 PG 4 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900011 PM 11328072 ER PT J AU Schafer, T Shuryak, EV AF Schafer, T Shuryak, EV TI Implications of the ALEPH tau-lepton decay data for perturbative and nonperturbative QCD SO PHYSICAL REVIEW LETTERS LA English DT Article ID HADRONIC WIDTH; VACUUM; INSTANTONS AB We use ALEPH data on hadronic tau decays in order to calculate Euclidean coordinate space correlation functions in the vector and axial-vector channels. The linear combination V - A receives no perturbative contribution and is quantitatively reproduced by the instanton liquid model. In the case of V + A the instanton calculation is in good agreement with the data once perturbative corrections are included. These corrections clearly show the evolution of alpha (s). We also analyze the range of validity of the operator product expansion (OPE). We conclude that the range of validity of the OPE is limited to x less than or equal to 0.3 fm, whereas the instanton model describes the data over the entire range. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. RP Schafer, T (reprint author), SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. OI Schaefer, Thomas/0000-0002-2297-782X NR 19 TC 24 Z9 24 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 APR 30 PY 2001 VL 86 IS 18 BP 3973 EP 3976 DI 10.1103/PhysRevLett.86.3973 PG 4 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900012 PM 11328073 ER PT J AU Ivanov, EI Stienike, DL Ryabchikov, DI Adams, GS Adams, T Bar-Yam, Z Bishop, JM Bodyagin, VA Brown, DS Cason, NM Chung, SU Cummings, JP Danyo, K Denisov, SP Dorofeev, VA Dowd, JP Eugenio, P Fan, XL Hackenburg, RW Hayek, M Joffe, D Kachaev, IA Kern, W King, E Kodolova, OL Korotkikh, VL Kostin, MA Kuhn, J Lipaev, VV LoSecco, JM Manak, JJ Napolitano, J Nozar, M Olchanski, C Ostrovidov, AI Pedlar, TK Popov, AV Sarycheva, LI Seth, KK Shen, X Shenhav, N Shephard, WD Sinev, NB Smith, JA Taegar, SA Tomaradze, A Vardanyan, IN Weygand, DP White, DB Willutzki, HJ Witkowski, M Yershov, AA AF Ivanov, EI Stienike, DL Ryabchikov, DI Adams, GS Adams, T Bar-Yam, Z Bishop, JM Bodyagin, VA Brown, DS Cason, NM Chung, SU Cummings, JP Danyo, K Denisov, SP Dorofeev, VA Dowd, JP Eugenio, P Fan, XL Hackenburg, RW Hayek, M Joffe, D Kachaev, IA Kern, W King, E Kodolova, OL Korotkikh, VL Kostin, MA Kuhn, J Lipaev, VV LoSecco, JM Manak, JJ Napolitano, J Nozar, M Olchanski, C Ostrovidov, AI Pedlar, TK Popov, AV Sarycheva, LI Seth, KK Shen, X Shenhav, N Shephard, WD Sinev, NB Smith, JA Taegar, SA Tomaradze, A Vardanyan, IN Weygand, DP White, DB Willutzki, HJ Witkowski, M Yershov, AA CA E852 Collaboration TI Observation of exotic meson production in the reaction pi(-)p -> eta 'pi(-)p at 18 GeV/c SO PHYSICAL REVIEW LETTERS LA English DT Article ID FLUX-TUBE MODEL; HYBRID MESONS; STATE; QCD AB An amplitude analysis of an exclusive sample of 5765 events from the reaction pi (-) p --> eta ' pi (-) p at 18 GeV/c is described. The eta ' pi (-) production is dominated by natural parity exchange and by three partial waves: those with J(PC) = 1(-+), 2(++), and 4(++). A mass-dependent analysis of the partial-wave amplitudes indicates the production of the a(2)(1320) meson as well as the a(4)(2040) meson, observed for the first time decaying to eta ' pi (-). The dominant, exotic (non-q (q) over bar) 1(-+) partial wave is shown to be resonant with a mass of 1.597 +/- 0.010(-0.010)(+0.045) GeV/c(2) and a width of 0.340 +/- 0.040 +/- 0.050 GeV/c(2). This exotic state, the pi (1)(1600). is produced with a t dependence which is different from that of the a(2)(1320) meson, indicating differences between the production mechanisms for the two states. C1 Univ Notre Dame, Notre Dame, IN 46556 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Inst High Energy Phys, Protvino, Russia. Univ Massachusetts Dartmouth, N Dartmouth, MA 02747 USA. Moscow MV Lomonosov State Univ, Moscow, Russia. Northwestern Univ, Evanston, IL 60208 USA. Rensselaer Polytech Inst, Troy, NY 12180 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Univ Notre Dame, Notre Dame, IN 46556 USA. RI Vardanyan, Irina/K-7981-2012 NR 22 TC 115 Z9 116 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 APR 30 PY 2001 VL 86 IS 18 BP 3977 EP 3980 DI 10.1103/PhysRevLett.86.3977 PG 4 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900013 PM 11328074 ER PT J AU Soff, S Bass, SA Dumitru, A AF Soff, S Bass, SA Dumitru, A TI Pion interferometry at RHIC: Probing a thermalized quark-gluon plasma? SO PHYSICAL REVIEW LETTERS LA English DT Article ID HEAVY-ION COLLISIONS; HADRONIC FREEZE-OUT; NUCLEAR COLLISIONS; DYNAMICS; EXPANSION; MATTER; MODELS AB We calculate the Gaussian radius parameters of the pion-emitting source in high-energy heavy-ion collisions, assuming a first-order phase transition from a thermalized quark-gluon plasma (QGP) to a gas of hadrons. Such a model leads to a very long-lived dissipative hadronic rescattering phase which dominates the properties of the two-pion correlation functions. The radii are found to depend only weakly on the thermalization time tau (1) the critical temperature T-c. (and thus the latent heat), and the specific entropy of the QGP. The model calculations suggest a rapid increase of R-out/R-side as a function of K-T if a thermalized QGP were formed. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Duke Univ, Dept Phys, Durham, NC 27708 USA. Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. RP Soff, S (reprint author), Brookhaven Natl Lab, Dept Phys, POB 5000, Upton, NY 11973 USA. OI Bass, Steffen/0000-0002-9451-0954 NR 44 TC 101 Z9 101 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 APR 30 PY 2001 VL 86 IS 18 BP 3981 EP 3984 DI 10.1103/PhysRevLett.86.3981 PG 4 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900014 PM 11328075 ER PT J AU Kimura, WD van Steenbergen, A Babzien, M Ben-Zvi, I Campbell, LP Cline, DB Dilley, CE Gallardo, JC Cottschalk, SC He, P Kusche, KP Liu, Y Pantell, RH Pogorelsky, IV Quimby, DC Skaritka, J Steinhauer, LC Yakimenko, V AF Kimura, WD van Steenbergen, A Babzien, M Ben-Zvi, I Campbell, LP Cline, DB Dilley, CE Gallardo, JC Cottschalk, SC He, P Kusche, KP Liu, Y Pantell, RH Pogorelsky, IV Quimby, DC Skaritka, J Steinhauer, LC Yakimenko, V TI First staging of two laser accelerators SO PHYSICAL REVIEW LETTERS LA English DT Article AB Staging of two laser-driven, relativistic electron accelerators has been demonstrated for the first time in a proof-of-principle experiment, whereby two distinct and serial laser accelerators acted on an electron beam in a coherently cumulative manner. Output from a CO2 laser was split into two beams to drive two inverse free electron lasers (IFEL) separated by 2.3 m. The first IFEL served to bunch the electrons into similar to3 fs microbunches, which were rephased with the laser wave in the second IFEL. This represents a crucial step towards the development of practical laser-driven electron accelerators. C1 STI Optron Inc, Bellevue, WA 98004 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Stanford Univ, Stanford, CA 94305 USA. Univ Washington, Redmond Plasma Phys Lab, Redmond, WA 98052 USA. RP Kimura, WD (reprint author), STI Optron Inc, Bellevue, WA 98004 USA. OI Gallardo, Juan C/0000-0002-5191-3067 NR 12 TC 74 Z9 75 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 APR 30 PY 2001 VL 86 IS 18 BP 4041 EP 4043 DI 10.1103/PhysRevLett.86.4041 PG 3 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900029 PM 11328090 ER PT J AU Kim, M Duscher, G Browning, ND Sohlberg, K Pantelides, ST Pennycook, SJ AF Kim, M Duscher, G Browning, ND Sohlberg, K Pantelides, ST Pennycook, SJ TI Nonstoichiometry and the electrical activity of grain boundaries in SrTiO3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID ENERGY-LOSS SPECTROSCOPY; FIRST-PRINCIPLES; SPACE-CHARGE; ELECTRONIC-STRUCTURE; DEFECT CHEMISTRY; ATOMIC-STRUCTURE; METAL-OXIDES; SEGREGATION; STATE; TILT AB A combination of experiments and first-principles calculations is used to show that grain boundaries in SrTiO3 are intrinsically nonstoichiometric. Total-energy calculations reveal that the introduction of nonstoichiometry into the grain boundaries is energetically favorable and results in structures that are consistent with atomic-resolution Z-contrast micrographs. Electron energy-loss spectra provide direct evidence of nonstoichiometry. These results and calculations for nonstoichiometric grain boundaries provide an explanation of the microscopic origin of the "double Schottky barriers" that dominate the electrical behavior of polycrystalline oxides. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Illinois, Dept Phys, Chicago, IL 60612 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Duscher, Gerd/G-1730-2014; Kim, Miyoung/C-8316-2012; OI Duscher, Gerd/0000-0002-2039-548X; Browning, Nigel/0000-0003-0491-251X NR 32 TC 122 Z9 123 U1 6 U2 54 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 APR 30 PY 2001 VL 86 IS 18 BP 4056 EP 4059 DI 10.1103/PhysRevLett.86.4056 PG 4 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900033 PM 11328094 ER PT J AU Kolton, AB Dominguez, D Gronbech-Jensen, N AF Kolton, AB Dominguez, D Gronbech-Jensen, N TI Mode locking in ac-driven vortex lattices with random pinning SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHARGE-DENSITY WAVES; PERIODIC MEDIA; LOGARITHMIC INTERACTIONS; SUPERCONDUCTING FILM; SHAPIRO STEPS; PHASE; INTERFERENCE; MOTION; FLOW; TRANSITION AB We find mode-locking steps in simulated current-voltage characteristics of ac-driven vortex lattices with random pinning. For low frequencies there is mode locking above a finite ac force amplitude, while for large frequencies there is mode locking for any small ac force. This is correlated with the nature of temporal order in the different regimes in the absence of ac drive. The mode-locked state is a frozen solid pinned in the moving reference of frame, and the depinning from the step shows plastic flow and hysteresis. C1 Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RP Kolton, AB (reprint author), Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. RI Dominguez, Daniel/E-9304-2016; OI Dominguez, Daniel/0000-0002-6204-0150; Kolton, Alejandro B./0000-0002-9050-5859 NR 37 TC 63 Z9 63 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 APR 30 PY 2001 VL 86 IS 18 BP 4112 EP 4115 DI 10.1103/PhysRevLett.86.4112 PG 4 WC Physics, Multidisciplinary SC Physics GA 429PJ UT WOS:000168525900047 PM 11328108 ER PT J AU Gamwo, IK Soong, Y Lyczkowski, RW AF Gamwo, IK Soong, Y Lyczkowski, RW TI Numerical simulation and experimental validation of solids flows in a bubbling fluidized bed (vol 103, pg 117, 1999) SO POWDER TECHNOLOGY LA English DT Correction C1 US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. RP Gamwo, IK (reprint author), Univ Akron, Dept Mech Engn, Akron, OH 44325 USA. NR 1 TC 0 Z9 0 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD APR 30 PY 2001 VL 115 IS 3 BP 312 EP 312 DI 10.1016/S0032-5910(00)00342-9 PG 1 WC Engineering, Chemical SC Engineering GA 425MT UT WOS:000168295200012 ER PT J AU Hasan, T Praphairaksit, N Houk, RS AF Hasan, T Praphairaksit, N Houk, RS TI Low flow, externally air cooled torch for inductively coupled plasma atomic emission spectrometry with axial viewing SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article DE inductively coupled plasma (ICP); ICP atomic emission spectrometry (ICP-AES); ICP, torch design; ICP, axial viewing; ICP, low flow ID VACUUM ULTRAVIOLET-RADIATION; OPTICAL-SAMPLING ORIFICE; MASS-SPECTROMETRY; ANALYTE EMISSION; ICP AB The torch wall is cooled largely by air passing through a cooling jacket added to the outside of a Fassel torch. The plasma is viewed axially through a cooled cone interface centered on the axial channel. The outer argon gas flow can be reduced to 7 l min(-1) with no compromise in performance or torch lifetime. The plasma exhibits the same 'robustness index' and interference effects from Na as the conventional, high-flow ICP supplied with the particular spectrometer used. Detection limits (DL) for lines at similar to 200 nm are poorer by approximately a factor of two, while those for lines at similar to 400 nm are actually better than values typically seen for the same lines by axial viewing of a conventional, high-flow ICP. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Dept Chem, Ames Lab, US Dept Energy, Ames, IA 50011 USA. RP Houk, RS (reprint author), Iowa State Univ Sci & Technol, Dept Chem, Ames Lab, US Dept Energy, Ames, IA 50011 USA. NR 17 TC 7 Z9 7 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0584-8547 J9 SPECTROCHIM ACTA B JI Spectroc. Acta Pt. B-Atom. Spectr. PD APR 30 PY 2001 VL 56 IS 4 BP 409 EP 418 DI 10.1016/S0584-8547(01)00168-9 PG 10 WC Spectroscopy SC Spectroscopy GA 440PK UT WOS:000169183400006 ER PT J AU Xu, QH Ma, YZ Fleming, GR AF Xu, QH Ma, YZ Fleming, GR TI Heterodyne detected transient grating spectroscopy in resonant and non-resonant systems using a simplified diffractive optics method SO CHEMICAL PHYSICS LETTERS LA English DT Article ID STIMULATED RAMAN-SCATTERING; DETERMINISTIC PROTEIN MOTIONS; DYNAMICS; LIQUIDS; SOLVATION AB We report a simplified optical heterodyne detected transient grating setup consisting of a single diffractive optical element based on modifications of the arrangement used by Miller and co-workers [J. Phys. Chem. A, 103 (1999) 10619]. Our arrangement features ease of alignment, suppression of scattering and is free of pump-probe contamination in the detected transient grating signals. The capability of our arrangement is demonstrated by measurements on a nonresonant system, CS2, and a resonant system, malachite green in ethanol. (C) 2001 Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Phys Biosci, Berkeley, CA 94720 USA. RP Fleming, GR (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Xu, Qing-Hua/B-1478-2013; Ma, Yingzhong/L-6261-2016 OI Xu, Qing-Hua/0000-0002-4153-0767; Ma, Yingzhong/0000-0002-8154-1006 NR 28 TC 54 Z9 54 U1 0 U2 10 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 APR 27 PY 2001 VL 338 IS 4-6 BP 254 EP 262 DI 10.1016/S0009-2614(01)00281-0 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 430TN UT WOS:000168591800007 ER PT J AU Li, H Colgate, SA Wendroff, B Liska, R AF Li, H Colgate, SA Wendroff, B Liska, R TI Rossby wave instability of thin accretion disks. III. Nonlinear simulations SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; hydrodynamics; instabilities; waves ID DIFFERENTIALLY ROTATING-DISKS; TRANSPORT; PROPAGATION; DRIVEN AB We study the nonlinear evolution of the Rossby wave instability in thin disks using global two-dimensional hydrodynamic simulations. The detailed linear theory of this nonaxisymmetric instability was developed earlier by Lovelace et al. and Li et al., who found that the instability can be excited when there is an extremum in the radial profile of an entropy-modified version of potential vorticity. The key questions we are addressing in this paper are the following : (1) What happens when the instability becomes nonlinear ? Specifically, does it lead to vortex formation? (2) What is the detailed behavior of a vortex ? (3) Can the instability sustain itself and can the vortex last a long time? Among various initial equilibria that we have examined, we generally find that there are three stages of the disk evolution : (1) The exponential growth of the initial small amplitude perturbations. This is in excellent agreement with the linear theory; (2) The production of large-scale vortices and their interactions with the background flow, including shocks. Significant accretion is observed owing to these vortices. (3) The coupling of Rossby waves/vortices with global spiral waves, which facilitates further accretion throughout the whole disk. Even after more than 20 revolutions at the radius of vortices, we find that the disk maintains a state that is populated with vortices, shocks, spiral waves/shocks, all of which transport angular momentum outward. We elucidate the physics at each stage and show that there is an efficient outward angular momentum transport in stages (2) and (3) over most parts of the disk, with an equivalent Shakura-Sunyaev angular momentum transport parameter alpha in the range from 10(-4) to 10(-2). By carefully analyzing the flow structure around a vortex, we show why such vortices prove to be almost ideal "units" in transporting angular momentum outward, namely by positively correlating the radial and azimuthal velocity components. In converting the gravitational energy to the internal energy, we find some special cases in which entropy can remain the same while angular momentum is transported. This is different from the classical a-disk model, which results in the maximum dissipation (or entropy production). The dependence of the transport efficiency on various physical parameters are examined and effects of radiative cooling are briefly discussed as well. We conclude that Rossby wave/vortex instability is an efficient, purely hydrodynamic mechanism for angular momentum transport in thin disks, and may find important applications in many astrophysical systems. C1 Univ Calif Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. Czech Tech Univ, Fac Nucl Sci & Phys Engn, CR-11519 Prague, Czech Republic. RP Li, H (reprint author), Univ Calif Los Alamos Natl Lab, Div Appl Phys, T-6,MS B288, Los Alamos, NM 87545 USA. RI Liska, Richard/C-3142-2009 OI Liska, Richard/0000-0002-6149-0440 NR 26 TC 122 Z9 123 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 APR 26 PY 2001 VL 551 IS 2 BP 874 EP 896 DI 10.1086/320241 PN 1 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 427AX UT WOS:000168383600023 ER PT J AU Mozharivskyj, Y Franzen, HF AF Mozharivskyj, Y Franzen, HF TI High-temperature modification of Y5Sb3 and its ternary analogue Y5NixSb3-x SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE high-temperature modification of yttrium antimonide; partial substitution of antimony by nickel; crystal structure; bonding; Pauli paramagnets ID CRYSTAL-STRUCTURE; ELECTRONIC-STRUCTURE; SUBSTITUTION; NICKEL; STABILIZATION; HF5CO1+XP3-X; PHOSPHORUS; PHASE; BI AB The high-temperature modification of Y5Sb3 has been discovered: the Yb5Sb3 structure type, Pnma space group, a=11.867(1), h=9.2247(9) and c=8.0977(8) Angstrom. It has been estimated that the first-order structural transition from the low-temperature form (Mn,Si, type) to the high-temperature form is above 1265 degreesC but below 1400 degreesC. Antimony atoms on one of the two sites can be partially substituted by Ni atoms, which results in a Y5NixSb3-x formula with 0 less than or equal tox<1. The high-temperature structure was refined for a Y5Ni0.38Sb2.62 crystal, obtained by annealing a sample in an induction furnace for 2 h at 1265C. All high-temperature nickel-containing phases Y5NixSb3-x with the ordered Yb5Sb3 structure undergo a decomposition to low-temperature Y5Sb3 (Mn5Si3 type) and a nickel-containing phase, when annealed at 800 degreesC. Extended Huckel tight-binding calculations show that substitution of Sb by Ni is unfavorable with respect to the Y-Sb bonding. The structure of Y5NixSb3-x is stabilized by the configurational entropy, resulting from a statistical mixture of Sb and Ni atoms on one site. Choice of an Sb site to be occupied by Ni is dictated by bonding maximization in the substituted structure. The high-temperature Y5Sb3 and Y5Ni0.38Sb2.62 phases are weak Pauli paramagnets. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RP Franzen, HF (reprint author), Iowa State Univ, Dept Chem, 342 Spedding Hall, Ames, IA 50011 USA. NR 29 TC 23 Z9 23 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD APR 26 PY 2001 VL 319 IS 1-2 BP 100 EP 107 DI 10.1016/S0925-8388(00)01463-8 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 423YG UT WOS:000168204900018 ER PT J AU Smith, DM Neu, MP Garcia, E Dole, VR AF Smith, DM Neu, MP Garcia, E Dole, VR TI Reaction chemistry of plutonium with vanadium pentoxide in molten salts SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE nuclear reactor materials; oxide materials; liquid-solid reactions; X-ray diffraction ID MAGNESIUM ORTHOVANADATE AB Vanadium pentoxide, V2O5, has been proposed as an oxidant for the stabilization of reduced forms of plutonium within pyrochemical salt residues from plutonium pyrochemical processes at the Rocky Flats Environmental Technology Site because of its large reduction potential and its ability to react via normal solid-state reactions. However, when V2O5 was used to oxidize actual process residues results were highly variable. This paper discusses the reaction chemistry of PuCl3, Pu degrees and PuOCl with V2O5 under a variety of conditions, including in the presence and absence of a NaCl/KCl salt matrix. This work is the first systematic study of the solid-state oxidation of plutonium species by vanadium pentoxide. For PuCl3 a greater than or equal to 1:1 V2O5:PuCl3 ratio is needed for complete oxidation. Increasing the amount of V2O5 from 1 to 2 equivalents increases the contribution of side reactions, including reactions of V2O5 with the process equipment and/or salt matrix, and produces undesirable non-volatile ternary and quaternary vanadium compounds. The oxidation of PuOCl is similar to that of PuCl3. Greater than a 1:1 V2O5:PuOCl ratio is required to achieve adequate conversion of PuOCI to PuO2. Oxidation of Pu degrees by V2O5 is more complex than the PuCl3, or PuOCl oxidations. Complete oxidation of Pu degrees to Pu(IV) in the presence of the salt matrix does not occur with up to 6 equivalents of V2O5. However, conversion of Pu degrees to Pu(IV) occurs rapidly in the absence of the salt matrix. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Neu, MP (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Mail Stop G739, Los Alamos, NM 87545 USA. NR 21 TC 14 Z9 14 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD APR 26 PY 2001 VL 319 IS 1-2 BP 258 EP 265 DI 10.1016/S0925-8388(01)00874-X PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 423YG UT WOS:000168204900042 ER PT J AU Groenewold, GS Hodges, BDM Scott, JR Gianotto, AK Appelhans, AD Kessinger, GF Wright, JB AF Groenewold, GS Hodges, BDM Scott, JR Gianotto, AK Appelhans, AD Kessinger, GF Wright, JB TI Oxygen-for-sulfur exchange in the gas phase: Reactions of Al and Si oxyanions with H2S SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ION MASS-SPECTROMETRY; SOIL PARTICLES; TRAP; ADSORPTION; AEROSOL; SUBSURFACE; CATALYSTS; MINERALS; SMECTITE; SULFIDE AB Gas-phase Si and Al oxyanions were formed by particle bombardment, isolated by mass, and then reacted with H2S in an ion trap secondary ion mass spectrometer (IT-SIMS). The reactions proceeded by different reaction pathways depending on whether the oxyanions were even- or odd-electron species. The radical anion SiO2bullet- reacted with H2S by abstracting a(bullet)SH radical to form the even-electron Sio(2)SH(-). Once formed, the even electron Sio(2)SH(-) reacted with a second H2S molecule by O-for-S exchange to form SiOS2H-. The radical anion SiO3bullet- abstracted an H-bullet radical from H2S to form even-electron SiO3H-, which then underwent two consecutive O-for-S exchange reactions with H2S to form SiO2SH- and SiOS2H-. For the reactions of the even-electron anion AlO2-, the products of two consecutive O-for-S exchange reactions with H2S were AlOS- and AlS2-. The radical abstraction reactions and the O-for-S exchange reactions of SiO3H-, AlO2 and AlOS- were efficient in the 30-50% range. The efficiency of the O-for-S exchange reaction of SiO2SH- (producing SiOS2H-) was substantially less efficient at 8%. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Natick Soldier Ctr, Natick, MA 01760 USA. RP Groenewold, GS (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RI Scott, Jill/G-7275-2012 NR 42 TC 17 Z9 17 U1 2 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD APR 26 PY 2001 VL 105 IS 16 BP 4059 EP 4064 DI 10.1021/jp004495q PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 428BR UT WOS:000168441700016 ER PT J AU Wilson, AN Timar, J Ahmad, I Astier, A Azaiez, F Bergstrom, MH Blumenthal, DJ Crowell, B Carpenter, MP Ducroux, L Gall, BJP Hannachi, F Hubel, H Khoo, TL Janssens, RVF Korichi, A Lauritsen, T Lopez-Martens, A Meyer, M Nisius, D Paul, ES Porqueth, MG Redon, N Sharpey-Scafer, JF Wadsworth, R Wilson, JN Ragnarsson, I AF Wilson, AN Timar, J Ahmad, I Astier, A Azaiez, F Bergstrom, MH Blumenthal, DJ Crowell, B Carpenter, MP Ducroux, L Gall, BJP Hannachi, F Hubel, H Khoo, TL Janssens, RVF Korichi, A Lauritsen, T Lopez-Martens, A Meyer, M Nisius, D Paul, ES Porqueth, MG Redon, N Sharpey-Scafer, JF Wadsworth, R Wilson, JN Ragnarsson, I TI Magnetic dipole bands in Hg-190: first evidence of excitations across the Z=82 sub-shell in Hg nuclei SO PHYSICS LETTERS B LA English DT Article ID ROTATIONAL BANDS; OBLATE BAND; ISOTOPES AB An experiment aimed at studying high-spin states in Hg-190 was performed with the Eurogam II array. The data have revealed the presence of cascades of magnetic dipole transitions with some unexpected properties. Unlike the M1 bands previously observed in the heavier tig isotopes, these structures have extremely large B(M1)/B(E2) ratios. The observation of a third dipole band with much lower B(M1)/B(E2) values in the same spin/excitation energy regime suggests that the bands may represent configurations occurring in different minima in the potential energy surface. Configuration-dependent Cranked Nilsson-Strutinsky calculations predict the presence of a minimum in the nuclear potential energy surface at a deformation of epsilon approximate to 0.2, gamma approximate to -90 degrees. occurring when a proton is excited across the Z = 82 shell-gap into an h(9/2) orbital. It is suggested that the bands exhibiting anomalously large B(MI)/B(E2) ratios may be associated with this minimum. (C) 2001 Published by Elsevier Science B.V. C1 Univ York, Dept Phys, York YO10 5DD, N Yorkshire, England. Inst Nucl Res, H-4001 Debrecen, Hungary. Argonne Natl Lab, Argonne, IL 60439 USA. Inst Phys Nucl, F-69622 Villeurbanne, France. Inst Phys Nucl, F-91406 Orsay, France. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. IReS, F-67037 Strasbourg, France. CSNSM, F-91405 Orsay, France. Univ Bonn, ISKP, D-5300 Bonn, Germany. Lund Inst Technol, Dept Math Phys, S-22100 Lund, Sweden. RP Wilson, AN (reprint author), Australian Natl Univ, Res Sch Phys Sci & Engn, Dept Nucl Phys, Canberra, ACT 0200, Australia. RI Carpenter, Michael/E-4287-2015; OI Carpenter, Michael/0000-0002-3237-5734; Wilson, Anna/0000-0001-6928-1689 NR 22 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 26 PY 2001 VL 505 IS 1-4 BP 6 EP 14 DI 10.1016/S0370-2693(01)00332-X PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 429PG UT WOS:000168525700002 ER PT J AU Chen, L Blank, B Brown, BA Chartier, M Galonsky, A Hansen, PG Thoennessen, M AF Chen, L Blank, B Brown, BA Chartier, M Galonsky, A Hansen, PG Thoennessen, M TI Evidence for an l=0 ground state in He-9 SO PHYSICS LETTERS B LA English DT Article DE stripping reactions with radioactive nuclear beams; He-9 ground state ID NUCLEUS; LI-10; BE-11 AB The unbound nuclear systems Li-10 and He-9 were produced in direct reactions of 28 MeV/u Be-11 incident on a Be-9 target, The distributions of the observed velocity differences between the neutron and the charged fragment show a strong influence of final-state interactions. Since the neutron originates in a dominant I = 0 initial state, a selection-rule argument allows a firm 1 = 0 assignment for the lowest odd-neutron state in Li-10. We report the results suggesting a very similar unbound state in He-9. characterized by an s-wave scattering length more negative than -10 fm corresponding to an energy of the virtual state of less than 0.2 MeV. Shell-model calculations cast light on the reasons for the disappearance of the magic shell gap near the drip line. (C) 2001 Published by Elsevier Science B.V. C1 Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. CEN Bordeaux Gradignan, F-33175 Gradignan, France. RP Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. EM thoennessen@nscl.msu.edu NR 25 TC 69 Z9 70 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 APR 26 PY 2001 VL 505 IS 1-4 BP 21 EP 26 DI 10.1016/S0370-2693(01)00313-6 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 429PG UT WOS:000168525700004 ER PT J AU Zaghib, K Song, X Kinoshita, K AF Zaghib, K Song, X Kinoshita, K TI Thermal analysis of the oxidation of natural graphite: isothermal kinetic studies SO THERMOCHIMICA ACTA LA English DT Article DE thermal analysis; natural graphite; oxidation ID IRREVERSIBLE CAPACITY; PARTICLE-SIZE; CARBON; SURFACE; OXYGEN AB The oxidation kinetics of natural graphite particles (2-40 mum average particle size) with a flake-like morphology were investigated at 933, 982 and 1033 K. The reaction rate in air increased with increase in temperature and with a decrease in particle size of natural graphite. The activation energy, derived from the classical Arrhenius relationship, was 188 +/- 2.2 kJ/mol, in good agreement with published results. The activation energies of the natural graphite did not show any systematic trend with particle size. The rate constant, normalized for the area of active sites, is independent of the particle size and Brunauer-Emmet-Teller (BET) surface area, which strongly suggests that the edge sites play a significant role in the oxidation kinetics. This observation is consistent with conclusions reported in the literature that the oxidation kinetics of carbonaceous materials decreases with a decrease in active surface area. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Inst Rech Hydro Quebec, Varennes, PQ J3X 1S1, Canada. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Zaghib, K (reprint author), Inst Rech Hydro Quebec, 1800 Boul Lionel Boulet, Varennes, PQ J3X 1S1, Canada. EM karimz@ireq.ca NR 20 TC 27 Z9 27 U1 2 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD APR 26 PY 2001 VL 371 IS 1-2 BP 57 EP 64 DI 10.1016/S0040-6031(01)00428-2 PG 8 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 423YL UT WOS:000168205300010 ER PT J AU Reitz, TL Lee, PL Czaplewski, KF Lang, JC Popp, KE Kung, HH AF Reitz, TL Lee, PL Czaplewski, KF Lang, JC Popp, KE Kung, HH TI Time-resolved XANES investigation of CuO/ZnO in the oxidative methanol reforming reaction SO JOURNAL OF CATALYSIS LA English DT Article DE autothermal; methanol; CuO/ZnO/Al2O3; oxidative reforming; XANES ID TEMPERATURE-PROGRAMMED REDUCTION; CUO-ZNO CATALYSTS; COPPER; CU/ZNO/AL2O3 AB CuO/ZnO catalysts were examined by time-resolved X-ray absorption spectroscopy during oxidative reforming of methanol, tinder low oxygen conversion conditions, Cu2+ was the dominant copper species and combustion of methanol to carbon dioxide and water was the primary reaction. After complete oxygen conversion, Cu2+ was reduced to Cu-0 while the principal activity of the catalyst shifted to steam reforming, where the dominant product was hydrogen. Cu+ was observed as a transient species in the reduction of Cu2+ to Cu-0 and no activity was attributed to it. Increasing the oxygen partial pressure increased the rate of reduction of Cu2+ This observation was attributed to a heating effect associated with an enhancement of the combustion rate. Additional experiments showed that the catalyst could recover its original activity after a reduction/oxidation cycle. (C) 2001 Academic Press. C1 Northwestern Univ, Dept Chem Engn, Evanston, IL 60208 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Kung, HH (reprint author), Northwestern Univ, Dept Chem Engn, Evanston, IL 60208 USA. RI Kung, Harold/B-7647-2009 NR 25 TC 97 Z9 99 U1 7 U2 22 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9517 J9 J CATAL JI J. Catal. PD APR 25 PY 2001 VL 199 IS 2 BP 193 EP 201 DI 10.1006/jcat.2000.3141 PG 9 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 427ZZ UT WOS:000168437800005 ER PT J AU Monteiro, RS Zemlyanov, D Storey, JM Ribeiro, FH AF Monteiro, RS Zemlyanov, D Storey, JM Ribeiro, FH TI Turnover rate and reaction orders for the complete oxidation of methane on a palladium foil in excess dioxygen SO JOURNAL OF CATALYSIS LA English DT Article DE palladium foil; palladium oxide; turnover rate for methane combustion; reaction orders for methane combustion; model catalysts ID X-RAY PHOTOELECTRON; PD-PARTICLE-SIZE; CATALYTIC COMBUSTION; ALUMINA CATALYSTS; PD/GAMMA-ALUMINA; LATTICE OXYGEN; METAL-OXIDES; SURFACE; XPS; BEHAVIOR AB The turnover rate and reaction orders for the combustion of methane in excess oxygen over Pd foils were in agreement with literature results reported for supported catalysts. The rate equation was r = k[CH4](0.7)[O-2](0.2)[H2O] (-0.9). The turnover rate on the Pd foil was 59 x 10(-2) s(-1) at 550 K, 160 Torr O-2, 16 Ton CH4, 1 Torr H2O, and N-2 balance to 800 Ton; with the number of active sites defined as the number of surface Pd atoms calculated from the initial geometric area of the foil. This rate is 3 times higher than the highest value reported in the literature for supported catalysts. The surface area of the foil, measured by isotopic exchange of surface oxygen with O-18(2), increased by a factor of approximately 2 after reaction, The main species observed on the surface after reaction by XPS was PdO, Sample activation during the reaction was not observed. The reaction was carried out in a batch reactor at 598 K and atmospheric pressure with characterization before and after reaction by X-ray and Auger spectroscopies and temperature-programmed desorption, (C) 2001 Academic Press. C1 Worcester Polytech Inst, Dept Chem Engn, Worcester, MA 01609 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ribeiro, FH (reprint author), Worcester Polytech Inst, Dept Chem Engn, Worcester, MA 01609 USA. OI Monteiro, Robson/0000-0003-0818-7431; Ribeiro, Fabio/0000-0001-7752-461X NR 58 TC 63 Z9 63 U1 1 U2 17 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9517 J9 J CATAL JI J. Catal. PD APR 25 PY 2001 VL 199 IS 2 BP 291 EP 301 DI 10.1006/jcat.2001.3176 PG 11 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 427ZZ UT WOS:000168437800015 ER PT J AU Sessler, JL Sathiosatham, M Brown, CT Rhodes, TA Wiederrecht, G AF Sessler, JL Sathiosatham, M Brown, CT Rhodes, TA Wiederrecht, G TI Hydrogen-bond-mediated photoinduced electron-transfer: Novel dimethylaniline-anthracene ensembles formed via Watson-Crick base-pairing SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID MODEL SYSTEM; INTERFACE; BINDING; SPECTROSCOPY; FLUORESCENCE; PROTEIN; DIIMIDE; EPR AB The synthesis of a new, noncovalent anthracene-dimethylaniline dyad (ensemble I) held together via guanosine-cytidine Watson-Crick base-pairing interactions is reported. Upon excitation at 420 nm, photoinduced electron-transfer from the dimethylaniline donor to the singlet excited state of the anthracene acceptor occurs, as inferred from a combination of time-resolved fluorescence quenching and transient absorption measurements. In toluene at room temperature, the rate constants for photoinduced intraensemble electron-transfer and subsequent back-electron-transfer (charge recombination) are k(CS) = (3.5 +/- 0.03) x 10(10) s(-1) and k(CR) = (1.42 +/- 0.03) x 10(9) s(-1), respectively. C1 Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA. Univ Rochester, Ctr Photoinduced Electron Transfer, Rochester, NY 14618 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Sessler, JL (reprint author), Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA. FU NIGMS NIH HHS [GM 41657] NR 29 TC 81 Z9 81 U1 1 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD APR 25 PY 2001 VL 123 IS 16 BP 3655 EP 3660 DI 10.1021/ja005547s PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA 428CA UT WOS:000168442500005 PM 11457097 ER PT J AU Gee, RH Fried, LE Cook, RC AF Gee, RH Fried, LE Cook, RC TI Structure of chlorotrifluoroethylene/vinylidene fluoride random copolymers and homopolymers by molecular dynamics simulations SO MACROMOLECULES LA English DT Article ID SMALL-PENETRANT DIFFUSION; POLY(VINYLIDENE FLUORIDE); GLASS-TRANSITION; FORCE-FIELD; CONFORMATIONAL DYNAMICS; FREE-VOLUME; POLYMERS; POLY(CHLOROTRIFLUOROETHYLENE); POLY(TETRAFLUOROETHYLENE); POLYETHYLENE AB We perform molecular dynamics simulations of chlorotrifluoroethylene (CTFE)/vinylidene fluoride (VDF) copolymers over a wide range of compositions and temperatures including the volumetric glass transition. Structural features of the polymers and copolymers were characterized using pair correlation functions and wide-angle X-ray scattering (WAXS) spectra. Calculated WAXS spectra for the CTFE/VDF copolymer known as Kel-F 800 are compared with experimental results and are found to compare well; The X-ray peak associated with interchain spacing is found to shift to larger scattering angles (smaller d spacings) as the concentration of the CTFE comonomer decreases, suggesting a transition between CTFE and VDF homopolymer interchain packing structures, consistent with earlier experiments. The strong compositional dependence is traced to packing involving the CF2 moiety. The calculated WAXS were further deconvoluted into atom-atom contributions in an attempt to explain the origin of the peak positions found in the WAXS. The location of the first peak in the spectra did not correspond to interchain packing distances for any of the polymer compositions except the VDF homopolymer. The effect of Coulombic interactions on polymer structure is examined. We find that the importance of Coulombic interactions is greatest for pVDF. The torsional angle distribution and the characteristic ratio show greater sensitivities to Coulombic interactions than the density and the total radial distribution function. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94551 USA. RP Gee, RH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, POB 808,L-268, Livermore, CA 94551 USA. RI Fried, Laurence/L-8714-2014 OI Fried, Laurence/0000-0002-9437-7700 NR 48 TC 21 Z9 22 U1 1 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD APR 24 PY 2001 VL 34 IS 9 BP 3050 EP 3059 DI 10.1021/ma001077a PG 10 WC Polymer Science SC Polymer Science GA 424MT UT WOS:000168236600045 ER PT J AU Lozykowski, HJ Jadwisienczak, WM Brown, I AF Lozykowski, HJ Jadwisienczak, WM Brown, I TI Cathodoluminescence study of GaN doped with Tb SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article; Proceedings Paper CT Spring Meeting of the European-Materials-Research-Society CY MAY 29-JUN 02, 2000 CL STRASBOURG, FRANCE SP European Mat Res Soc DE CL; GaN : Tb; CL rare earth kinetics; CL depth resolved spectra ID RED-LIGHT EMISSION; VISIBLE CATHODOLUMINESCENCE; PHOTOLUMINESCENCE; ELECTROLUMINESCENCE; ER AB We report the observation of the visible cathodoluminescence (CL of GaN doped with Tb3+ ions incorporated by implantation. The sharp characteristic emission lines corresponding to Tb3+ transitions are resolved in the spectral range from 350 to 750 nm. and observed over the temperature range of 7-330 K. The luminescence shows transitions which originate in the D-5(3) and D-5(4) levels and terminate in the F-7 manifolds. The depth resolved CL spectra analysis give the luminescence surface dead laver thickness of similar to 20 nm. The yellow band starts to grow at 5 keV (corresponding to electron penetration depth similar to 219 nm). The time resolved spectra, and rise and decay kinetics are discussed. The decay times for D-5(3) --> F-7(5) (423.4 nm) and D-5(4) --> F-7(5) (551.6 nm) transitions at 7 K are similar to 0.7 and similar to 1.8 ms, with little change with temperature. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Ohio Univ, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. Ohio Univ, Condensed Matter & Surface Sci Program, Stocker Ctr, Athens, OH 45701 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lozykowski, HJ (reprint author), Ohio Univ, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. NR 14 TC 8 Z9 8 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5107 J9 MAT SCI ENG B-SOLID JI Mater. Sci. Eng. B-Solid State Mater. Adv. Technol. PD APR 24 PY 2001 VL 81 IS 1-3 BP 140 EP 143 DI 10.1016/S0921-5107(00)00697-8 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 427EX UT WOS:000168392800035 ER PT J AU Isaenko, L Yelisseyev, A Tkachuk, A Ivanova, S Vatnik, S Merkulov, A Payne, S Page, R Nostrand, M AF Isaenko, L Yelisseyev, A Tkachuk, A Ivanova, S Vatnik, S Merkulov, A Payne, S Page, R Nostrand, M TI New laser crystals based on KPb2Cl5 for IR region SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article; Proceedings Paper CT Spring Meeting of the European-Materials-Research-Society CY MAY 29-JUN 02, 2000 CL STRASBOURG, FRANCE SP European Mat Res Soc DE double chlorides; growth; absorption; luminescence; laser ID AMPLIFIERS AB The KPb2Cl5 single crystals, doped by different Rare Earth ions were grown. The RE segregation coefficient was found to decrease from 1.0 to 0.15 in the set from Nd to Yb. Spectroscopic properties and luminescence decay were studied, stimulated emission was demonstrated at 1.06 mum (Nd3+) and at 2.43 mum (Dy3+). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, Design & Technol Inst Monocrystals, SB, Novosibirsk 630058, Russia. SI Vavilov State Opt Inst, St Petersburg 199034, Russia. Inst Laser Phys, Novosibirsk 630090, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Isaenko, L (reprint author), Russian Acad Sci, Design & Technol Inst Monocrystals, SB, 43 Russkaya Str, Novosibirsk 630058, Russia. RI Isaenko, Ludmila/H-7620-2013; Yelisseyev, Alexander/A-3846-2014; Isaenko, Ludmila/A-5272-2014 NR 6 TC 52 Z9 55 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5107 J9 MAT SCI ENG B-SOLID JI Mater. Sci. Eng. B-Solid State Mater. Adv. Technol. PD APR 24 PY 2001 VL 81 IS 1-3 BP 188 EP 190 DI 10.1016/S0921-5107(00)00735-2 PG 3 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 427EX UT WOS:000168392800050 ER PT J AU DeWoody, JA Fletcher, DE Wilkins, SD Avise, JC AF DeWoody, JA Fletcher, DE Wilkins, SD Avise, JC TI Genetic documentation of filial cannibalism in nature SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID TESSELLATED DARTER; RECOGNITION; KIN; DNA; POLYMORPHISM; STICKLEBACK; PERCIDAE; STRATEGY; CARE AB Cannibalism is widespread in natural populations of fishes, where the stomachs of adults frequently contain conspecific juveniles. Furthermore, field observations suggest that guardian males routinely eat offspring from their own nests. However, recent genetic paternity analyses have shown that fish nests often contain embryos not sired by the nest-tending male (because of cuckoldry events, egg thievery, or nest piracy). Such findings, coupled with the fact that several fish species have known capabilities for distinguishing kin from nonkin. raise the possibility that cannibalism by guardian males is directed primarily or exclusively toward unrelated embryos in their nests. Here, we test this hypothesis by collecting freshly cannibalized embryos from the stomachs of several nest-tending darter and sunfish males in nature and determining their genetic parentage by using polymorphic microsatellite markers. Our molecular results clearly indicate that guardian males do indeed consume their own genetic offspring, even when unrelated (foster) embryos are present within the nest. These data provide genetic documentation of filial cannibalism in nature. Furthermore, they suggest that the phenomenon may result, at least in part, from an inability of guardians to differentiate between kin and nonkin within their own nests. C1 Univ Georgia, Dept Genet, Athens, GA 30602 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. S Carolina Aquarium, Charleston, SC 29413 USA. RP DeWoody, JA (reprint author), Purdue Univ, Dept Forestry & Nat Resources, W Lafayette, IN 47907 USA. EM dewoody@fnr.purdue.edu RI DeWoody, James/C-4909-2008 OI DeWoody, James/0000-0002-7315-5631 NR 32 TC 29 Z9 30 U1 0 U2 7 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 APR 24 PY 2001 VL 98 IS 9 BP 5090 EP 5092 DI 10.1073/pnas.091102598 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 425VC UT WOS:000168311500053 PM 11309508 ER PT J AU Snyder, JP Nettles, JH Cornett, B Downing, KH Nogales, E AF Snyder, JP Nettles, JH Cornett, B Downing, KH Nogales, E TI The binding conformation of Taxol in beta-tubulin: A model based on electron crystallographic density SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID SIDE-CHAIN; COMMON PHARMACOPHORE; PACLITAXEL TAXOL(R); BIOLOGICAL-ACTIVITY; CRYSTAL-STRUCTURE; ALPHA-TUBULIN; CANCER-CELLS; AMINO-ACIDS; ANALOGS; MICROTUBULE AB The chemotherapeutic drug Taxol is known to interact within a specific site on beta -tubulin. Although the general location of the site has been defined by photoaffinity labeling and electron crystallography. the original data were insufficient to make an absolute determination of the bound conformation. We have now correlated the crystallographic density with analysis of Taxol conformations and have found the unique solution to be a T-shaped Taxol structure. This T-shaped or butterfly structure is optimized within the beta -tubulin site and exhibits functional similarity to a portion of the B9-B10 loop in the alpha -tubulin subunit. The model provides structural rationalization for a sizeable body of Taxol structure-activity relationship data, including binding affinity, photoaffinity labeling, and acquired mutation in human cancer cells. C1 Emory Univ, Dept Chem, Atlanta, GA 30322 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Snyder, JP (reprint author), Emory Univ, Dept Chem, 1515 Pierce Dr, Atlanta, GA 30322 USA. NR 48 TC 273 Z9 282 U1 2 U2 21 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 APR 24 PY 2001 VL 98 IS 9 BP 5312 EP 5316 DI 10.1073/pnas.051309398 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 425VC UT WOS:000168311500091 PM 11309480 ER PT J AU Heimberg, JA Wahl, KJ Singer, IL Erdemir, A AF Heimberg, JA Wahl, KJ Singer, IL Erdemir, A TI Superlow friction behavior of diamond-like carbon coatings: Time and speed effects SO APPLIED PHYSICS LETTERS LA English DT Article ID WEAR; FILMS AB The friction behavior of a diamond-like carbon coating was studied in reciprocating sliding contact at speeds from 0.01 to 5 mm/s, in dry nitrogen. "Superlow" friction coefficients of 0.003-0.008 were obtained in continuous sliding at the higher speeds (>1 mm/s). However, friction coefficients rose to values typical of diamond-like carbon in dry and ambient air (0.01-0.1) at lower speeds (<0.5 mm/s) as well as in time-delayed, higher speed tests. The rise of the friction coefficients in both speed and time-delay tests was in good quantitative agreement with gas adsorption kinetics predicted by the Elovich equation for adsorption onto carbon. More generally, superlow friction could be sustained, suppressed, and recovered as a function of exposure time, demonstrating that duty cycle cannot be ignored when predicting performance of superlow friction coatings in devices. (C) 2001 American Institute of Physics. C1 USN, Res Lab, Tribol Sect, Washington, DC 20375 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Heimberg, JA (reprint author), USN, Res Lab, Tribol Sect, Code 716, Washington, DC 20375 USA. OI Wahl, Kathryn/0000-0001-8163-6964 NR 19 TC 138 Z9 142 U1 4 U2 38 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 23 PY 2001 VL 78 IS 17 BP 2449 EP 2451 DI 10.1063/1.1366649 PG 3 WC Physics, Applied SC Physics GA 425RC UT WOS:000168304600012 ER PT J AU Colton, JS Yu, PY AF Colton, JS Yu, PY TI What determines the emission peak energy of the blue luminescence in highly Mg-doped p-GaN? SO APPLIED PHYSICS LETTERS LA English DT Article ID PHOTOLUMINESCENCE BANDS; EXCITATION; COMPENSATION; YELLOW AB We report a study of the 2.8 eV blue luminescence (BL) in heavily Mg-doped p-GaN via resonant excitation with a tunable blue dye laser. The dependence of the BL on the excitation photon energy (E-ex) is unlike that of the yellow luminescence found in n-type GaN. An Urbach-type band tail, with Urbach parameter of 33 meV is observed in the vicinity of the BL energy. We propose that the peak energy of the BL marks the transition from localized states to delocalized states within this band tail. (C) 2001 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 Colton, JS (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 19 TC 10 Z9 10 U1 1 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 23 PY 2001 VL 78 IS 17 BP 2500 EP 2502 DI 10.1063/1.1367904 PG 3 WC Physics, Applied SC Physics GA 425RC UT WOS:000168304600029 ER PT J AU Zehmann, CA Boyle, TJ Pedrotty, DM Alam, TM Lang, DP Scott, BL AF Zehmann, CA Boyle, TJ Pedrotty, DM Alam, TM Lang, DP Scott, BL TI Tl-203,Tl-205 NMR studies of crystallographically characterized thallium alkoxides. X-ray structures of [Tl(OCH2CMe3)](4) and [Tl(OAr)](infinity), where OAr=OC6H3(Me)(2)-2,6 and OC6H3(CHMe2)(2)-2,6 SO INORGANIC CHEMISTRY LA English DT Article ID MOLECULAR-STRUCTURES; LEAD COMPOUNDS; CHEMISTRY; CRYSTAL; DERIVATIVES; COMPLEXES; ACIDITIES; ALCOHOLS AB [Tl(OCH2Me)]4 (1) was reacted with excess HOR to prepare a series of [Tl(OR)](n), where OR = OCHMe2 (2, n = 4), OCMe3 (3, n = 4), OCH2CMe3 (4, n = 4), OC6H3(Me)(2)-2,6 (5, n = infinity), and OC6H3(CHMe2)(2)-2,6 (6, n = infinity). Single-crystal X-ray diffraction experiments revealed that in the solid state the alkoxide-ligated compound 4 adopts a cubane structure, whereas the aryloxide derivatives, 5 and 6, formed polymeric chains. Compounds 1-6 were also characterized by Tl-203,Tl-205 solution and Tl-205 solid-state NMR spectroscopy. In solution it was determined that 1-4 retained the [Tl-O]4 cube structure, whereas the polymeric species 5 and 6 appeared to be fluxional. Variations in the solution and solid-state structures for the [Tl(OR)](4) cubes and polymeric (Tl(OAr)](infinity) are influenced by the steric hindrance of the ligand. The acidity of the parent alcohol influences the degree of covalency at the Ti metal center, which is reflected in the Tl-203,Tl-205 chemical shifts for 1-6. C1 Sandia Natl Labs, Adv Mat Lab, Albuquerque, NM 87106 USA. Sandia Natl Labs, Dept Organ Mat, Albuquerque, NM 87185 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Xray Diffract Lab, Los Alamos, NM 87545 USA. RP Boyle, TJ (reprint author), Sandia Natl Labs, Adv Mat Lab, 101 Univ Blvd SE, Albuquerque, NM 87106 USA. RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 48 TC 0 Z9 0 U1 0 U2 4 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 APR 23 PY 2001 VL 40 IS 9 BP 2177 EP 2184 PG 8 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 423DB UT WOS:000168159200029 ER PT J AU Kang, JS Kim, YJ Lee, BW Olson, CG Min, BI AF Kang, JS Kim, YJ Lee, BW Olson, CG Min, BI TI The valence state of Ce in electron-doped manganites: La0.7Ce0.3MnO3 SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID RESONANT PHOTOEMISSION; TRANSPORT; SURFACE; MAGNETORESISTANCE; LA1-XSRXMNO3; SPECTROSCOPY; TRANSITION; OXIDE; FILMS; LA AB The electronic structure of La0.7Ce0.3MnO3 (LCeMO) has been investigated by using photoemission spectroscopy. A very weak 4f resonance is observed and the Ce 3d spectrum of LCeMO is very similar to that of CeO2, indicating that Ce ions are far from being trivalent. The Mn 2p con-level spectrum of LCeMO is essentially the same as that of hole-doped La0.7Sr0.3MnO3, but different from that of MnO, The local spin-density approximation (LSDA) electronic structure calculations for LCeMO show that the Mn 3d states contribute a large peak around -2 eV and a weak structure between -2 eV and E-F and that the O 2p states are spread between -3 eV and -9 eV, with negligible contribution near E-F. The LSDA calculations for LCeMO and hole-doped La0.7Ba0.3MnO3 reveal that the calculated Mn 3d density of states at E-F in LCeMO is larger, reflecting the effect of electron doping with Ce ions. C1 Catholic Univ Korea, Dept Phys, Puchon 422743, South Korea. Hankuk Univ Foreign Studies, Dept Phys, Kyungki 449791, South Korea. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Pohang Univ Sci & Technol, Dept Phys, Pohang 790784, South Korea. RP Kang, JS (reprint author), Catholic Univ Korea, Dept Phys, Puchon 422743, South Korea. NR 32 TC 41 Z9 41 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD APR 23 PY 2001 VL 13 IS 16 BP 3779 EP 3789 DI 10.1088/0953-8984/13/16/308 PG 11 WC Physics, Condensed Matter SC Physics GA 430RH UT WOS:000168589000010 ER PT J AU Nakamura, T Aumann, T Bazin, D Blumenfeld, Y Brown, BA Caggiano, J Clement, R Glasmacher, T Lofy, PA Navin, A Pritychenko, BV Sherrill, BM Yurkon, J AF Nakamura, T Aumann, T Bazin, D Blumenfeld, Y Brown, BA Caggiano, J Clement, R Glasmacher, T Lofy, PA Navin, A Pritychenko, BV Sherrill, BM Yurkon, J TI Structure of the halo nucleus He-6 studied via the Li-6(t,He-3)He-6 reaction SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 7th International Topical Conference on Giant Resonances (GR 2000) CY JUN 12-15, 2000 CL OSAKA UNIV, OSAKA, JAPAN HO OSAKA UNIV ID CHARGE-EXCHANGE REACTIONS; COULOMB DISSOCIATION; LI-11; EXCITATION C1 Tokyo Inst Technol, Dept Phys, Meguro Ku, Tokyo 1528551, Japan. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Michigan State Univ, Dept Chem, E Lansing, MI 48824 USA. Inst Phys Nucl, IN2P3, CNRS, F-91406 Orsay, France. Bhabha Atom Res Ctr, Bombay 400085, Maharashtra, India. RP Nakamura, T (reprint author), Tokyo Inst Technol, Dept Phys, Meguro Ku, 2-12-1 Ookayama, Tokyo 1528551, Japan. RI Glasmacher, Thomas/C-4462-2008; Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011; Aumann, Thomas/B-1455-2012; Glasmacher, Thomas/H-9673-2014; Nakamura, Takashi/N-5390-2015 OI Glasmacher, Thomas/0000-0001-9436-2448; Nakamura, Takashi/0000-0002-1838-9363 NR 19 TC 1 Z9 1 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 APR 23 PY 2001 VL 687 IS 1-2 BP 97C EP 102C PG 6 WC Physics, Nuclear SC Physics GA 416WX UT WOS:000167804300016 ER PT J AU Varner, RL Beene, JR Chartier, M Liang, JF Shapira, D Bazin, D Blank, B Sherrill, B Thoennessen, M DeYoung, PA Peaslee, GF AF Varner, RL Beene, JR Chartier, M Liang, JF Shapira, D Bazin, D Blank, B Sherrill, B Thoennessen, M DeYoung, PA Peaslee, GF TI Excitation of the isovector giant quadrupole resonance in Pb-208 by Coulomb inelastic scattering SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 7th International Topical Conference on Giant Resonances (GR 2000) CY JUN 12-15, 2000 CL OSAKA UNIV, OSAKA, JAPAN HO OSAKA UNIV C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Hope Coll, Holland, MI 49422 USA. RP Varner, RL (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RI Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011 NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD APR 23 PY 2001 VL 687 IS 1-2 BP 140C EP 145C PG 6 WC Physics, Nuclear SC Physics GA 416WX UT WOS:000167804300022 ER PT J AU Kusnezov, D Alhassid, Y Snover, KA Ormand, WE AF Kusnezov, D Alhassid, Y Snover, KA Ormand, WE TI Giant dipole resonances in hot, rotating nuclei: Nuclear shapes and shell corrections SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 7th International Topical Conference on Giant Resonances (GR 2000) CY JUN 12-15, 2000 CL OSAKA UNIV, OSAKA, JAPAN HO OSAKA UNIV ID EXCITED NUCLEI; SN-120; PB-208; WIDTH C1 Yale Univ, Sloane Phys Lab, Ctr Theoret Phys, New Haven, CT 06520 USA. Univ Washington, Nucl Phys Lab, Seattle, WA 98195 USA. Univ Calif Lawrence Livermore Natl Lab, Phys Directorate, Livermore, CA 94551 USA. RP Kusnezov, D (reprint author), Yale Univ, Sloane Phys Lab, Ctr Theoret Phys, New Haven, CT 06520 USA. NR 6 TC 3 Z9 3 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 APR 23 PY 2001 VL 687 IS 1-2 BP 212C EP 219C PG 8 WC Physics, Nuclear SC Physics GA 416WX UT WOS:000167804300032 ER PT J AU Heckman, P Bazin, D Beene, JR Blumenfeld, Y Chromik, MJ Halbert, ML Liang, JF Mohrmann, E Nakamura, T Navin, A Sherrill, BM Snover, KA Thoennessen, M Tryggestad, E Varner, RL AF Heckman, P Bazin, D Beene, JR Blumenfeld, Y Chromik, MJ Halbert, ML Liang, JF Mohrmann, E Nakamura, T Navin, A Sherrill, BM Snover, KA Thoennessen, M Tryggestad, E Varner, RL TI Temperature dependence of the GDR width in Sn-120 SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 7th International Topical Conference on Giant Resonances (GR 2000) CY JUN 12-15, 2000 CL OSAKA UNIV, OSAKA, JAPAN HO OSAKA UNIV ID GIANT-DIPOLE RESONANCE; INELASTIC ALPHA-SCATTERING; ENERGY DEPOSITION; NUCLEI; PB-208 C1 Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. Univ Washington, Nucl Phys Lab, Seattle, WA 98195 USA. CNRS, IN2P3, F-91406 Orsay, France. Tokyo Inst Technol, Dept Phys, Tokyo 1528551, Japan. Bhabha Atom Res Ctr, Div Nucl Phys, Mumbai 400085, India. RP Heckman, P (reprint author), Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. RI Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011; Nakamura, Takashi/N-5390-2015 OI Nakamura, Takashi/0000-0002-1838-9363 NR 12 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 APR 23 PY 2001 VL 687 IS 1-2 BP 225C EP 230C PG 6 WC Physics, Nuclear SC Physics GA 416WX UT WOS:000167804300034 ER PT J AU Tryggestad, E Aumann, T Bazin, D Beene, JR Blumenfeld, Y Chartier, M Halbert, ML Heckman, P Liang, JF Radford, DC Shapira, D Sherrill, BM Thoennessen, M Varner, RL AF Tryggestad, E Aumann, T Bazin, D Beene, JR Blumenfeld, Y Chartier, M Halbert, ML Heckman, P Liang, JF Radford, DC Shapira, D Sherrill, BM Thoennessen, M Varner, RL TI Dipole strength function in O-20 SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 7th International Topical Conference on Giant Resonances (GR 2000) CY JUN 12-15, 2000 CL OSAKA UNIV, OSAKA, JAPAN HO OSAKA UNIV ID OXYGEN ISOTOPES; GIANT-RESONANCES; DRIP-LINE; NUCLEI; PARTICLE; PHOTONS C1 Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. GSI Darmstadt, D-64291 Darmstadt, Germany. IN2P3, F-91406 Orsay, France. CEN Bordeaux Gradignan, F-33175 Gradignan, France. RP Tryggestad, E (reprint author), Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. RI Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011; Aumann, Thomas/B-1455-2012; radford, David/A-3928-2015 NR 17 TC 12 Z9 12 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 APR 23 PY 2001 VL 687 IS 1-2 BP 231C EP 236C DI 10.1016/S0375-9474(01)00626-1 PG 6 WC Physics, Nuclear SC Physics GA 416WX UT WOS:000167804300035 ER PT J AU Abbott, B Abdesselam, A Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Bacon, TC Baden, A Baldin, B Balm, PW Banerjee, S Barberis, E Baringer, P Bartlett, JF Bassler, U Bauer, D Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Beuselinck, R Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Duflot, L Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Filthaut, F Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gao, M Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Grinstein, S Groer, L Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hou, S Huang, Y Illingworth, R Ito, AS Jaffre, M Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, VE Landsberg, G Leflat, A Leggett, C Lehner, F 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 Manankov, V Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Nunnemann, T Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Papageorgiou, K Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Peters, O Petroff, P Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Rha, J Ridel, M Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sen, N Shabalina, E Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zheng, H Zhou, Z Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A AF Abbott, B Abdesselam, A Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Bacon, TC Baden, A Baldin, B Balm, PW Banerjee, S Barberis, E Baringer, P Bartlett, JF Bassler, U Bauer, D Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Beuselinck, R Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Duflot, L Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Filthaut, F Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gao, M Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Grinstein, S Groer, L Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hou, S Huang, Y Illingworth, R Ito, AS Jaffre, M Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, VE Landsberg, G Leflat, A Leggett, C Lehner, F 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 Manankov, V Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Nunnemann, T Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Papageorgiou, K Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Peters, O Petroff, P Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Rha, J Ridel, M Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sen, N Shabalina, E Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zheng, H Zhou, Z Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A CA D0 Collaboration TI Quasi-model-independent search for new high p(T) physics at D0 SO PHYSICAL REVIEW LETTERS LA English DT Article ID 2ND-GENERATION LEPTOQUARK PAIRS; PRODUCTION CROSS-SECTION; ROOT-S=1.8 TEV; P(P)OVER-BAR COLLISIONS; (P)OVER-BAR-P COLLISIONS; QUARK COMPOSITENESS; TRANSVERSE-MOMENTUM; Z-BOSONS; LIMITS; JETS AB We apply a quasi-model-independent strategy ("Sleuth") to search for new high p(T) physics in approximate to 100 pb(-1) of p (p) over bar collisions at roots = 1.8 TeV collected by the D0 experiment during 1992-1990 at the Familab Tevatron. We systematically analyze many exclusive final states and demonstrate sensitivity to a variety of models predicting new phenomena at the electroweak scale. No evidence of new high P-T physics is observed. C1 Univ Oklahoma, Norman, OK 73019 USA. 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, Prague, Czech Republic. Acad Sci Czech Republ, Inst Phys, Prague, Czech Republic. Univ San Francisco Quito, Quito, Ecuador. Univ Grenoble 1, Inst Sci Nucl, IN2P3, CNRS, Grenoble, France. Univ Mediterranee, CPPM, IN2P3, CNRS, Marseille, France. CNRS, Lab Accelerateur Lineaire, IN2P3, F-91405 Orsay, France. Univ Paris 06, LPNHE, IN2P3, CNRS, Paris, France. Univ Paris 07, LPNHE, IN2P3, CNRS, Paris, France. CEA Saclay, DAPNIA, Serv Phys Particules, Saclay, France. Panjab Univ, Chandigarh 160014, India. Univ Delhi, Delhi 110007, India. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Seoul Natl Univ, Seoul, South Korea. CINVESTAV, Mexico City 14000, DF, Mexico. FOM, Inst NIKHEF, NL-1098 SJ Amsterdam, Netherlands. Univ Amsterdam, NIKHEF H, Amsterdam, Netherlands. Univ Nijmegen, NIKHEF H, Nijmegen, Netherlands. Inst Nucl Phys, Krakow, Poland. Moscow 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. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. Calif State Univ Fresno, Fresno, CA 93740 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Hawaii, Honolulu, HI 96822 USA. Fermi 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 Sci & Technol, 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. 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. 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 Abbott, B (reprint author), Univ Oklahoma, Norman, OK 73019 USA. RI Belyaev, Alexander/F-6637-2015; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016; Canelli, Florencia/O-9693-2016; Santoro, Alberto/E-7932-2014; Peters, Michael/B-4973-2009; Shivpuri, R K/A-5848-2010; 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; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013 OI Belyaev, Alexander/0000-0002-1733-4408; Kim, Sun Kee/0000-0002-0013-0775; Sznajder, Andre/0000-0001-6998-1108; Canelli, Florencia/0000-0001-6361-2117; Baarmand, Marc/0000-0002-9792-8619; Bean, Alice/0000-0001-5967-8674; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; NR 19 TC 18 Z9 18 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 23 PY 2001 VL 86 IS 17 BP 3712 EP 3717 DI 10.1103/PhysRevLett.86.3712 PG 6 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300005 PM 11329306 ER PT J AU Cronin-Hennessy, D Lyon, AL Thorndike, EH Savinov, V Coan, TE Fadeyev, V Gao, YS Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, C Bukin, K Dambasuren, E Karamov, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Wang, JC Wolf, A Wu, J Kopp, S Kostin, M Mahmood, AH Csorna, SE Danko, I McLean, KW Xu, Z Godang, R Bonvicini, G Cinabro, D Dubrovin, M McGee, S Zhou, GJ Lipeles, E Pappas, SP Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Chen, GP Gritsan, A Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Drell, PS Duboscq, JE Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Hsu, L Jones, CD Kandaswamy, J Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Palmer, M Patterson, JR Peterson, D Riley, D Romano, A Thayer, JG Urner, D Valant-Spaight, B Viehhauser, G Warburton, A Avery, P Prescott, C Rubiera, AI Stoeck, H Yelton, J Brandenburg, G Ershov, A Kim, DYJ Wilson, R Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Stepaniak, CJ Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Saleem, M Timm, S Wappler, F Anastassov, A Eckhart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Schwarthoff, H Thayer, JB von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Chen, S Fast, J Hinson, JW Lee, J Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V AF Cronin-Hennessy, D Lyon, AL Thorndike, EH Savinov, V Coan, TE Fadeyev, V Gao, YS Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, C Bukin, K Dambasuren, E Karamov, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Wang, JC Wolf, A Wu, J Kopp, S Kostin, M Mahmood, AH Csorna, SE Danko, I McLean, KW Xu, Z Godang, R Bonvicini, G Cinabro, D Dubrovin, M McGee, S Zhou, GJ Lipeles, E Pappas, SP Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Chen, GP Gritsan, A Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Drell, PS Duboscq, JE Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Hsu, L Jones, CD Kandaswamy, J Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Palmer, M Patterson, JR Peterson, D Riley, D Romano, A Thayer, JG Urner, D Valant-Spaight, B Viehhauser, G Warburton, A Avery, P Prescott, C Rubiera, AI Stoeck, H Yelton, J Brandenburg, G Ershov, A Kim, DYJ Wilson, R Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Stepaniak, CJ Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Saleem, M Timm, S Wappler, F Anastassov, A Eckhart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Schwarthoff, H Thayer, JB von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Chen, S Fast, J Hinson, JW Lee, J Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V CA CLEO Collaboration TI Observation af the Omega(0)(c) charmed baryon at CLEO SO PHYSICAL REVIEW LETTERS LA English DT Article ID DETECTOR; MASSES AB The CLEO experiment at the CESR, collider has used 13.7 fb(-1) of data to search for the production of the Omega (0)(c) (css ground state) in e(+)e(-) collisions at roots similar or equal to 10.6 GeV. The modes used to study the Omega (0)(c) are Omega (-)pi (+), Omega (-)pi (+)pi (0), Xi (-)K(-)pi (+)pi (+), Xi (0)K(-)pi (+), and Omega (-)pi (+)pi (+)pi (-). We observe a signal of 40.4 +/- 9.0(stat) events at a mass of 2694.6 +/- 2.6(stat) 1.9(stat) MeV/c(2), for all modes combined. C1 Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Univ Texas, Austin, TX 78712 USA. Univ Texas Pan Amer, Edinburg, TX 78539 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Colorado, Boulder, CO 80309 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. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. RP Cronin-Hennessy, D (reprint author), Univ Rochester, 601 Elmwood Ave, Rochester, NY 14627 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014 OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039 NR 20 TC 10 Z9 10 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 23 PY 2001 VL 86 IS 17 BP 3730 EP 3734 DI 10.1103/PhysRevLett.86.3730 PG 5 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300009 PM 11329310 ER PT J AU Puttner, R Gremaud, B Delande, D Domke, M Martins, M Schlachter, AS Kaindl, G AF Puttner, R Gremaud, B Delande, D Domke, M Martins, M Schlachter, AS Kaindl, G TI Statistical properties of inter-series mixing in helium: From integrability to chaos SO PHYSICAL REVIEW LETTERS LA English DT Article ID DOUBLE-EXCITATION STATES; ERICSON REGIME; EXCITED-STATES; ENERGY-LEVELS; ATOM AB The photoionization spectrum of helium shows considerable complexity close to the double-ionization threshold. By analyzing the results from both our recent experiments and ab initio three- and one dimensional calculations, we show that the statistical properties of the spacings between neighboring energy levels clearly display a transition towards quantum chaos. C1 Free Univ Berlin, Inst Expt Phys, D-14195 Berlin, Germany. Univ Paris 06, Lab Kastler Brossel T12 E1, F-75005 Paris, France. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Puttner, R (reprint author), Free Univ Berlin, Inst Expt Phys, Arnimallee 14, D-14195 Berlin, Germany. OI Martins, Michael/0000-0002-1228-5029 NR 18 TC 48 Z9 48 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 23 PY 2001 VL 86 IS 17 BP 3747 EP 3750 DI 10.1103/PhysRevLett.86.3747 PG 4 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300013 PM 11329314 ER PT J AU Porcelli, TA Adamczak, A Bailey, JM Beer, GA Douglas, JL Faifman, MP Fujiwara, MC Huber, TM Kammel, P Kim, SK Knowles, PE Kunselman, AR Maier, M Markushin, VE Marshall, GM Mason, GR Mulhauser, F Olin, A Petitjean, C Zmeskal, J AF Porcelli, TA Adamczak, A Bailey, JM Beer, GA Douglas, JL Faifman, MP Fujiwara, MC Huber, TM Kammel, P Kim, SK Knowles, PE Kunselman, AR Maier, M Markushin, VE Marshall, GM Mason, GR Mulhauser, F Olin, A Petitjean, C Zmeskal, J CA TRIUMF Muonic Hydrogen Collaborati TI Measurement of the resonant d mu t molecular formation rate in solid HD SO PHYSICAL REVIEW LETTERS LA English DT Article ID TIME-OF-FLIGHT; CATALYZED FUSION; HYDROGEN; MIXTURE AB Measurements of muon-catalyzed dt fusion (d mut --> He-4 + n + mu (-)) in solid HD have been per formed. The theory describing the energy dependent resonant molecular formation rate for the reaction mut + HD --> [(d mut)pee]* is compared to experimental results in a pure solid HD target. Constraints on the rales are inferred through the use of a Monte Carlo model developed specifically for the experiment. From the time-of-flight analysis of fusion events, in 16 and 37 mug.cm(-2) targets, an average formation rate consistent with 0.897 +/- (0.046)(stat) +/- (0.166)(syst) times the theoretical prediction was obtained. C1 Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 3P6, Canada. Inst Nucl Phys, PL-31342 Krakow, Poland. Chester Technol, Chester, Cheshire, England. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. IV Kurchatov Atom Energy Inst, Russian Res Ctr, Moscow 123182, Russia. Gustavus Adolphus Coll, Dept Phys, St Peter, MN 56082 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Jeonbuk Natl Univ, Dept Phys, Jeonju 560756, South Korea. Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. Univ Wyoming, Dept Phys, Laramie, WY 82071 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. TRIUMF, Vancouver, BC V6T 2A3, Canada. Austrian Acad Sci, Inst Medium Energy Phys, A-1090 Vienna, Austria. RP Univ No British Columbia, Dept Phys, Prince George, BC V2N 4Z9, Canada. EM Porcelli@triumf.ca NR 19 TC 12 Z9 12 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 23 PY 2001 VL 86 IS 17 BP 3763 EP 3766 DI 10.1103/PhysRevLett.86.3763 PG 4 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300017 PM 11329318 ER PT J AU Raimondi, P Seryi, A AF Raimondi, P Seryi, A TI Novel final focus design for future linear colliders SO PHYSICAL REVIEW LETTERS LA English DT Article AB The length, complexity, and cost of the present final focus designs for linear colliders grow ver!; quickly with the beam energy. In this Letter, a novel final focus system is presented and compared with the one proposed for the Next Linear Collider (NLC Zeroth-Order Design Report, edited by T.O. Raubenheimer; SLAG Report No. 474, 1996). This new design has fewer optical elements and is much shorter, nonetheless achieving better chromatic properties. Moreover, the new system is more suitable for operation over a larger energy range. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Raimondi, P (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 8 TC 44 Z9 44 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 23 PY 2001 VL 86 IS 17 BP 3779 EP 3782 DI 10.1103/PhysRevLett.86.3779 PG 4 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300021 PM 11329322 ER PT J AU Baker, KL Estabrook, KG Drake, RP Afeyan, BB AF Baker, KL Estabrook, KG Drake, RP Afeyan, BB TI Alternative mechanism for omega(0)/2 emission in laser-produced plasmas SO PHYSICAL REVIEW LETTERS LA English DT Article ID 2-PLASMON DECAY INSTABILITY; GENERATION; FREQUENCY; LANGMUIR; SYSTEM; LIGHT; WAVES AB Several models have been proposed to explain the broad spectral features characteristic of omega (0)/2 emission observed in laser-produced plasmas. In this article, the electromagnetic decay instability is examined as an alternative explanation for this emission. It is shown that the electromagnetic decay instability is able to explain some of the spectral features observed from laser-produced plasmas. In addition, the electromagnetic decay instability is consistent with two other features observed in experiments: the efficient generation of electromagnetic energy :md the discrepancy in the levels of emission between the omega (0)/2 emission and the 3 omega (0)/2 emission. C1 Univ Calif Davis, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Baker, KL (reprint author), Univ Calif Davis, Livermore, CA 94551 USA. RI Drake, R Paul/I-9218-2012 OI Drake, R Paul/0000-0002-5450-9844 NR 23 TC 0 Z9 0 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 23 PY 2001 VL 86 IS 17 BP 3787 EP 3790 DI 10.1103/PhysRevLett.86.3787 PG 4 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300023 PM 11329324 ER PT J AU Lim, SH Shindo, D AF Lim, SH Shindo, D TI New source of stacking faults in heteroepitaxial systems SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRONIC-STRUCTURE; EPITAXIAL-GROWTH; THIN-FILMS; GAN AB A new stacking fault formation mechanism has been observed for the first time in ZnO/LiTaO3 heteroepitaxial films. Nigh resolution electron microscopy studies combined with electron diffraction and numerical image computation suggest that the observed type II intrinsic stacking faults in an epitaxial film can be dominantly formed as a result of tilting of the lattices between films and substrate required to maintain a particular orientation relationship. C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Tohoku Univ, Inst Multidisciplinary Res Adv Mat, Sendai, Miyagi 9808577, Japan. RP Lim, SH (reprint author), Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. RI Shindo, Daisuke/I-3865-2012 NR 24 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 APR 23 PY 2001 VL 86 IS 17 BP 3795 EP 3798 DI 10.1103/PhysRevLett.86.3795 PG 4 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300025 PM 11329326 ER PT J AU de la Figuera, J Pohl, K de la Fuente, OR Schmid, AK Bartelt, NC Carter, CB Hwang, RQ AF de la Figuera, J Pohl, K de la Fuente, OR Schmid, AK Bartelt, NC Carter, CB Hwang, RQ TI Direct observation of misfit dislocation glide on surfaces SO PHYSICAL REVIEW LETTERS LA English DT Article ID SCANNING-TUNNELING-MICROSCOPY; METAL; RECONSTRUCTION; MANIPULATION; INTERFACES; DIFFUSION; AU(111); PT(111); STRESS; FILMS AB Using scanning tunneling microscopy we have observed thermally induced dislocation glide in monolayer Cu films on Ru(0001) at room temperature. The motion is governed by a Peierls barrier that depends on the detailed structure of the dislocations, in particular upon whether the threading dislocations that terminate them are dissociated or not. Calculations based on the Frenkel-Kontorova model reproduce the threading dislocation structure and provide estimates of the Peierls barrier and dislocation stiffness which are consistent with experiment. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Univ Complutense Madrid, Dept Fis Mat, E-28040 Madrid, Spain. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. RP Pohl, K (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. RI de la Figuera, Juan/E-7046-2010; Rodriguez, Oscar/B-7118-2011 OI de la Figuera, Juan/0000-0002-7014-4777; Rodriguez, Oscar/0000-0002-6888-459X NR 20 TC 29 Z9 29 U1 2 U2 9 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 APR 23 PY 2001 VL 86 IS 17 BP 3819 EP 3822 DI 10.1103/PhysRevLett.86.3819 PG 4 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300031 PM 11329332 ER PT J AU Zhang, JD Dai, PC Fernandez-Baca, JA Plummer, EW Tomioka, Y Tokura, Y AF Zhang, JD Dai, PC Fernandez-Baca, JA Plummer, EW Tomioka, Y Tokura, Y TI Jahn-Teller phonon anomaly and dynamic phase fluctuations in La0.7Ca0.3MnO3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLOSSAL-MAGNETORESISTANCE MANGANITES; MANGANESE PEROVSKITES; LA1-XSRXMNO3; LA1-XCAXMNO3 AB Inelastic neutron scattering was used to study the temperature (T) dependence of the lattice excitations in La0.7Ca0.3MnO3. An optical Jahn-Teller phonon exhibits continuous but anomalous damping with increasing temperature in the ferromagnetic-metallic phase and collapses above the Curie temperature Te (240 K). We attribute this anomaly to the growing dynamic phase segregation as T --> T-C, thus providing evidence of local fluctuations associated with the short-range polaron or charge/orbital ordering in the ferromagnetic-metallic state. C1 Florida Int Univ, Dept Phys, Miami, FL 33199 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Joint Res Ctr Atom Technol, Tsukuba, Ibaraki 3050046, Japan. Univ Tokyo, Dept Appl Phys, Tokyo 1130033, Japan. RP Zhang, JD (reprint author), Florida Int Univ, Dept Phys, Miami, FL 33199 USA. 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 29 TC 36 Z9 36 U1 0 U2 10 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 APR 23 PY 2001 VL 86 IS 17 BP 3823 EP 3826 DI 10.1103/PhysRevLett.86.3823 PG 4 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300032 PM 11329333 ER PT J AU Noheda, B Cox, DE Shirane, G Park, SE Cross, LE Zhong, Z AF Noheda, B Cox, DE Shirane, G Park, SE Cross, LE Zhong, Z TI Polarization rotation via a monoclinic phase in the piezoelectric 92% PbZn1/3Nb2/3O3-8% PbTiO3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID X-RAY-DIFFRACTION; SINGLE-CRYSTALS; RELAXOR FERROELECTRICS; FIRST PRINCIPLES; TRANSITION; PB(ZN1/3NB2/3)O-3/9-PERCENT-PBTIO3; BEHAVIOR AB The origin of ultrahigh piezoelectricity in the relaxer ferroelectric PhZn1/3Nb2/3O3-PbTiO3 was studied with an electric field applied along the [001] direction. The zero-field rhombohedral R phase starts to follow the direct polarization path to tetragonal symmetry via an intermediate monoclinic M phase, but then jumps irreversibly to an alternate path involving a different type of monoclinic distortion. Details of the structure and domain configuration of this novel phase are described. This result suggests that there is a nearby R-M phase boundary as found in the Pb(Ti,Zr)O-3 system. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM noheda@bnl.gov NR 19 TC 502 Z9 509 U1 10 U2 108 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 APR 23 PY 2001 VL 86 IS 17 BP 3891 EP 3894 DI 10.1103/PhysRevLett.86.3891 PG 4 WC Physics, Multidisciplinary SC Physics GA 426FC UT WOS:000168338300049 PM 11329350 ER PT J AU Mulhollan, GA Subashiev, AV Clendenin, JE Garwin, EL Kirby, RE Maruyama, T Prepost, R AF Mulhollan, GA Subashiev, AV Clendenin, JE Garwin, EL Kirby, RE Maruyama, T Prepost, R TI Photovoltage effects in photoemission from thin GaAs layers SO PHYSICS LETTERS A LA English DT Article ID POLARIZED ELECTRON SOURCE; CHARGE LIMIT; PHOTOCATHODES; SURFACE; EMISSION AB A set of thin GaAs p-type negative electron affinity (NEA) photocathodes have been used to measure the yield of photoemitted electrons at high intensity excitation. The active layer thickness is 100 nm and the p-type doping ranges from 5 x 10(18) to 5 x 10(19) cm(-3) for a set of four samples. The results show that the surface escape probability is a linear function of the NEA energy. The surface photovoltage effect on photoemission is found to diminish to zero at a doping level of 5 x 1019 cm-3 The experimental results an shown to be in good agreement with calculations using a charge limit model based on surface photovoltage kinetics that assume a constant electron energy relaxation rate in the band bending region. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. St Petersburg State Tech Univ, St Petersburg 195251, Russia. RP Prepost, R (reprint author), Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. NR 24 TC 28 Z9 28 U1 1 U2 5 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 APR 23 PY 2001 VL 282 IS 4-5 BP 309 EP 318 DI 10.1016/S0375-9601(01)00202-X PG 10 WC Physics, Multidisciplinary SC Physics GA 430NB UT WOS:000168579100014 ER PT J AU Sygula, A Xu, GP Marcinow, Z Rabideau, PW AF Sygula, A Xu, GP Marcinow, Z Rabideau, PW TI 'Buckybowls'-introducing curvature by solution phase synthesis SO TETRAHEDRON LA English DT Article DE bowl-shaped aromatic hydrocarbons; buckybowls; strained rings ID CROSS-COUPLING REACTIONS; CORANNULENE; SEMIBUCKMINSTERFULLERENE; HALIDES; RING AB New, non-pyrolytic methods are presented for the synthesis of curved-surface, polynuclear aromatic hydrocarbons related to the fullerenes. Tetrabromocorannulene is conveniently prepared on a large scale and then converted to corannulene, and also used as a synthon for further elaboration. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Sygula, A (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. NR 49 TC 68 Z9 68 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4020 J9 TETRAHEDRON JI Tetrahedron PD APR 23 PY 2001 VL 57 IS 17 BP 3637 EP 3644 DI 10.1016/S0040-4020(01)00251-4 PG 8 WC Chemistry, Organic SC Chemistry GA 425NN UT WOS:000168297500013 ER PT J AU Andricioaei, I Straub, JE Voter, AF AF Andricioaei, I Straub, JE Voter, AF TI Smart darting Monte Carlo SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATION; TRANSITION-STATE THEORY; ATOMIC CLUSTERS; SYSTEMS; PHASE; CONSTANTS; WALKING; LIQUIDS AB The "Smart Walking" Monte Carlo algorithm is examined. In general, due to a bias imposed by the interbasin trial move, the algorithm does not satisfy detailed balance. While it has been shown that it can provide good estimates of equilibrium averages for certain potentials, for other potentials the estimates are poor. A modified version of the algorithm, Smart Darting Monte Carlo, which obeys the detailed balance condition, is proposed. Calculations on a one-dimensional model potential, on a Lennard-Jones cluster and on the alanine dipeptide demonstrate the accuracy and promise of the method for deeply quenched systems. (C) 2001 American Institute of Physics. C1 Boston Univ, Dept Chem, Boston, MA 02215 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Straub, JE (reprint author), Boston Univ, Dept Chem, 590 Commonwealth Ave, Boston, MA 02215 USA. NR 21 TC 34 Z9 35 U1 1 U2 13 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 22 PY 2001 VL 114 IS 16 BP 6994 EP 7000 DI 10.1063/1.1358861 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 420ZQ UT WOS:000168036900004 ER PT J AU Martin, MG Thompson, AP Nenoff, TM AF Martin, MG Thompson, AP Nenoff, TM TI Effect of pressure, membrane thickness, and placement of control volumes on the flux of methane through thin silicalite membranes: A dual control volume grand canonical molecular dynamics study SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CHEMICAL-POTENTIAL GRADIENT; MONTE-CARLO SIMULATIONS; LENNARD-JONES FLUIDS; PHASE-EQUILIBRIA; GAS PERMEATION; PARALLEL ALGORITHMS; COMPUTER-SIMULATION; DRIVEN DIFFUSION; CARBON NANOPORES; SIEVE MEMBRANES AB The flux of methane through the straight channels of thin silicalite membranes is studied via dual control volume grand canonical molecular dynamics. The adsorption layers on the surfaces of the thin membranes are found to provide a significant resistance to the flux of methane. This strong surface effect for thin membranes requires that the control volumes (where insertions and deletions are performed) must be placed far enough away from the membrane surface that they do not overlap with the surface adsorption layer. The permeance (flux/pressure drop) of methane through the surface layer is shown to be insensitive to both the average pressure and the pressure drop. In contrast, the permeance through the interior of the membrane increases with decreasing average pressure. These results are explained using a model which treats the transport through the surface barrier as driven by the pressure gradient and transport through the zeolite as driven by the chemical potential gradient. A new force field named DACNIS is presented which accurately describes the adsorption isotherms of methane and ethane in silicalite. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Martin, MG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 49 TC 53 Z9 53 U1 4 U2 13 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 22 PY 2001 VL 114 IS 16 BP 7174 EP 7181 DI 10.1063/1.1360256 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 420ZQ UT WOS:000168036900025 ER PT J AU Cui, ST Cummings, PT Cochran, HD AF Cui, ST Cummings, PT Cochran, HD TI Molecular simulation of the transition from liquidlike to solidlike behavior in complex fluids confined to nanoscale gaps SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MONTE-CARLO SIMULATION; THIN-FILMS; SOLVATION FORCES; BRANCHED ALKANES; EXTREME CONFINEMENT; PHASE-TRANSITIONS; SHEAR BEHAVIOR; RHEOLOGICAL PROPERTIES; DYNAMICS SIMULATIONS; N-DECANE AB We report molecular dynamics simulations at ambient temperature and pressure of dodecane films of thickness between three and eight molecular layers confined between mica surfaces. We use an accurate united-atom model for dodecane and an effective interaction between the dodecane and the confining mica surfaces that is consistent with the surface energy of a mica surface. At ambient normal pressure, the strong surface-fluid interaction leads to increased dodecane density as the wall spacing is narrowed, crossing into a density region corresponding to bulk solid when the confined film becomes narrower than six molecular layers. Correspondingly, we observed a dramatic transition from a liquidlike to an ordered, solidlike structure when the confined dodecane film is reduced from seven to six molecular layers, consistent with experimental observation of many orders of magnitude increase in viscosity at the same film thickness. The solidlike structure is characterized by the layering as well as the in-plane orientational order of the dodecane molecules. At an extreme confinement of three molecular layers, the solidlike confined film is able to sustain a nonzero shear stress. These results with realistic models provide an improved understanding of the solidlike behavior observed in surface force apparatus experiments. (C) 2001 American Institute of Physics. C1 Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. RP Cui, ST (reprint author), Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 48 TC 95 Z9 95 U1 2 U2 24 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 22 PY 2001 VL 114 IS 16 BP 7189 EP 7195 DI 10.1063/1.1359736 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 420ZQ UT WOS:000168036900027 ER PT J AU Gunther, U Zhuk, A AF Gunther, U Zhuk, A TI Remarks on dynamical stabilization of internal spaces in multidimensional cosmology SO CLASSICAL AND QUANTUM GRAVITY LA English DT Review ID MULTICOMPONENT PERFECT FLUID; FINE-STRUCTURE CONSTANT; ART. NO. 086001; EXTRA DIMENSIONS; TIME-VARIATION; SUPERSYMMETRY BREAKING; INFLATION; UNIVERSE; QUINTESSENCE; MILLIMETER AB The possibility of dynamical stabilization of an internal space is investigated for a multidimensional cosmological model with minimal coupled scalar field as the inflaton. It is shown that a successful dynamical compactification crucially depends on the type of interaction between the geometrical modulus field and the inflaton and its decay products. In the considered model a stable compactification can be ensured via trapping of the modulus field by a minimum of the effective potential. C1 Univ Potsdam, Inst Math, Gravitat Projekt, D-14415 Potsdam, Germany. Fermi Natl Accelerator Lab, NASA Fermilab Astrophys Ctr, Batavia, IL 60510 USA. CSIC, Inst Matemat & Fis Fundamental, Ctr Fis Miguel Catalan, E-28006 Madrid, Spain. Odessa State Univ, Dept Phys, UA-65100 Odessa, Ukraine. RP Gunther, U (reprint author), Univ Potsdam, Inst Math, Gravitat Projekt, Neuen Palais 10,PF 601553, D-14415 Potsdam, Germany. NR 108 TC 20 Z9 20 U1 0 U2 1 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 APR 21 PY 2001 VL 18 IS 8 BP 1441 EP 1460 DI 10.1088/0264-9381/18/8/303 PG 20 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 429FR UT WOS:000168505800003 ER PT J AU Hauger, M Honegger, A Jourdan, J Kubon, G Petitjean, T Rohe, D Sick, I Warren, G Wohrle, H Zhao, J Ent, R Mitchell, J Crabb, D Tobias, A Zeier, M Zihlmann, B AF Hauger, M Honegger, A Jourdan, J Kubon, G Petitjean, T Rohe, D Sick, I Warren, G Wohrle, H Zhao, J Ent, R Mitchell, J Crabb, D Tobias, A Zeier, M Zihlmann, B TI A high-precision polarimeter SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE Moller polarimeter; electron scattering; high precision (0.5%) ID MOLLER POLARIMETER; POLARIZATION; TARGET AB We have built a polarimeter in order to measure the electron beam polarization in hall C at JLAB. Using a superconducting solenoid to drive the pure-iron target foil into saturation, and a symmetrical setup to detect the Mailer electrons in coincidence, we achieve an accuracy of <1%. This sets a new standard for Moller polarimeters. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Basel, Dept Phys & Astron, CH-4056 Basel, Switzerland. Jefferson Lab, Newport News, VA 23606 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP Sick, I (reprint author), Univ Basel, Dept Phys & Astron, Klingelbergstr 82, CH-4056 Basel, Switzerland. NR 19 TC 58 Z9 58 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 2001 VL 462 IS 3 BP 382 EP 392 DI 10.1016/S0168-9002(01)00197-8 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435MU UT WOS:000168885900005 ER PT J AU Stanislaus, TDS Koetke, DD Allgower, C Bekrenev, V Benslama, K Berger, E Briscoe, WJ Clajus, M Comfort, JR Craig, K Gibson, A Grosnick, D Huber, GM Isenhower, D Kasprzyk, T Knecht, N Koulbardis, A Kozlenko, N Kruglov, S Kycia, T Lolos, GJ Lopatin, I Manley, DM Manweiler, R Marusic, A McDonald, S Nefkens, BMK Olmsted, J Papandreou, Z Peaslee, D Peterson, RJ Phaisangittisakul, N Pulver, M Ramirez, AF Shafi, A Slaus, I Spinka, H Starostin, A Staudenmaier, HM Supek, I Thoms, J Tippens, WB AF Stanislaus, TDS Koetke, DD Allgower, C Bekrenev, V Benslama, K Berger, E Briscoe, WJ Clajus, M Comfort, JR Craig, K Gibson, A Grosnick, D Huber, GM Isenhower, D Kasprzyk, T Knecht, N Koulbardis, A Kozlenko, N Kruglov, S Kycia, T Lolos, GJ Lopatin, I Manley, DM Manweiler, R Marusic, A McDonald, S Nefkens, BMK Olmsted, J Papandreou, Z Peaslee, D Peterson, RJ Phaisangittisakul, N Pulver, M Ramirez, AF Shafi, A Slaus, I Spinka, H Starostin, A Staudenmaier, HM Supek, I Thoms, J Tippens, WB TI Measurement of neutron detection efficiencies in NaI using the Crystal Ball detector SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE neutron efficiency in NaI; neutrons in GEANT ID DECAYS; ETA AB We report on a measurement of the neutron detection efficiency in NaI crystals in the Crystal Ball (CB) detector obtained from a study of pi (-)p --> pi degreesn reactions at the Brookhaven National Laboratory AGS. A companion GEANT-based Monte Carlo study has been done to simulate these reactions in the CB, and a comparison with the data is provided. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Valparaiso Univ, Dept Phys & Astron, Neils Sci Ctr, Valparaiso, IN 46383 USA. Abilene Christian Univ, Abilene, TX 79699 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Arizona State Univ, Tempe, AZ 85287 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Colorado, Boulder, CO 80309 USA. George Washington Univ, Washington, DC 20052 USA. Univ Karlsruhe, D-76128 Karlsruhe, Germany. Kent State Univ, Kent, OH 44242 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Maryland, College Pk, MD 20742 USA. Petersburg Nucl Phys Inst, St Petersburg 188350, Russia. Univ Regina, Regina, SK S4S 0A2, Canada. Rudjer Boskovic Inst, Zagreb 100000, Croatia. RP Koetke, DD (reprint author), Valparaiso Univ, Dept Phys & Astron, Neils Sci Ctr, Valparaiso, IN 46383 USA. EM donald.koetke@valpo.edu NR 12 TC 20 Z9 20 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 2001 VL 462 IS 3 BP 463 EP 473 DI 10.1016/S0168-9002(01)00180-2 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435MU UT WOS:000168885900015 ER PT J AU Borer, K Janos, S Li, Z Dezillie, B Da Via, C Granata, V Casagrande, L de Boer, RWI Lourenco, C Niinikoski, TO Palmieri, VG Chapuy, S Dimcovski, Z Grigoriev, E Bell, W Devine, SRH Ruggiero, G O'Shea, V Smith, K Berglund, P de Boer, W Hauler, F Heising, S Jungermann, L Abreu, M Rato, P Sousa, P Cindro, V Mikuz, M Zavrtanik, M Esposito, A Paul, S Buontempo, S D'Ambrosio, N Pagano, S Eremin, V Verbitskaya, E AF Borer, K Janos, S Li, Z Dezillie, B Da Via, C Granata, V Casagrande, L de Boer, RWI Lourenco, C Niinikoski, TO Palmieri, VG Chapuy, S Dimcovski, Z Grigoriev, E Bell, W Devine, SRH Ruggiero, G O'Shea, V Smith, K Berglund, P de Boer, W Hauler, F Heising, S Jungermann, L Abreu, M Rato, P Sousa, P Cindro, V Mikuz, M Zavrtanik, M Esposito, A Paul, S Buontempo, S D'Ambrosio, N Pagano, S Eremin, V Verbitskaya, E TI Charge collection efficiency of an irradiated cryogenic double-p silicon detector SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE cryogenic silicon detectors; Lazarus effect ID TEMPERATURES; GAAS AB We present results on the measurement of the charge collection efficiency of a p(+) /n/p(+) silicon detector irradiated to 1 x 10(15) n/cm(2), Operated in the temperature range between 80 and 200 K. For comparison, measurements obtained with a standard silicon diode (p(+) /n/n(+)), irradiated to the same fluence, are also presented. Both detectors show a dramatic increase of the CCE when operated at temperatures around 130 K. The double-p detector shows a higher CCE regardless of the applied bias and temperature, besides being symmetric with respect to the polarity of the bias voltage. C1 CERN, Div EP, CH-1211 Geneva 23, Switzerland. Univ Bern, Lab Hochenergiephys, CH-3012 Bern, Switzerland. Brookhaven Natl Lab, Upton, NY 11973 USA. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Univ Geneva, Dept Radiol, CH-1211 Geneva, Switzerland. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Helsinki Univ Technol, Low Temp Lab, FI-02150 Espoo, Finland. Univ Karlsruhe, IEKP, D-76128 Karlsruhe, Germany. LIP, P-1000 Lisbon, Portugal. Jozef Stefan Inst, Exp Particle Phys Dept, Ljubljana 1001, Slovenia. Tech Univ Munich, Dept Phys E18, D-85748 Garching, Germany. Univ Frederico II Napoli, Dipartimento Fis, Naples, Italy. Ist Nazl Fis Nucl, I-80125 Naples, Italy. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. RP Casagrande, L (reprint author), CERN, Div EP, CH-1211 Geneva 23, Switzerland. RI Zavrtanik, Marko/A-1524-2008; Rato Mendes, Pedro/F-8827-2010; Grigoriev, Eugene/K-6650-2013; O'Shea, Val/G-1279-2010; Verbitskaya, Elena/D-1521-2014; Pagano, Sergio/C-5332-2008; Paul, Stephan/F-7596-2015; Paul, Stephan/K-9237-2016; OI Zavrtanik, Marko/0000-0001-5606-6912; Rato Mendes, Pedro/0000-0001-9929-0869; D'Ambrosio, Nicola/0000-0001-9849-8756; Grigoriev, Eugene/0000-0001-7235-9715; O'Shea, Val/0000-0001-7183-1205; Pagano, Sergio/0000-0001-6894-791X; Paul, Stephan/0000-0002-8813-0437; Paul, Stephan/0000-0002-8813-0437; Abreu, Maria Conceicao/0000-0003-0093-7496 NR 13 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 2001 VL 462 IS 3 BP 474 EP 483 DI 10.1016/S0168-9002(01)00198-X PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435MU UT WOS:000168885900016 ER PT J AU Taylor, S Ahmad, S Distelbrink, J Mutchler, GS Smith, E Smith, T AF Taylor, S Ahmad, S Distelbrink, J Mutchler, GS Smith, E Smith, T TI The CLAS start counter SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE CLAS; plastic scintillator; time-of-eight; trigger ID BEAM AB The design, construction, and performance of a hexagonal-nose-cone-shaped plastic scintillation counter system is described. This "Start Counter" is used as part of the trigger and to measure event start times for photon beam running with CLAS in Hall B at the Thomas Jefferson National Accelerator Facility. The Start Counter is constructed of three 3-mm thick coupled-paddle scintillators and achieves a software-corrected time resolution of 260 ps. Each coupled-paddle scintillator operated without appreciable sagging up to similar to 1.2 MHz rate. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Rice Univ, TW Bonner Nucl Lab, Houston, TX 77251 USA. Baylor Coll Med, Dept Radiol, Houston, TX 77030 USA. Univ New Hampshire, Durham, NH 03824 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Mutchler, GS (reprint author), Rice Univ, TW Bonner Nucl Lab, Houston, TX 77251 USA. NR 7 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 2001 VL 462 IS 3 BP 484 EP 493 DI 10.1016/S0168-9002(00)01125-6 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435MU UT WOS:000168885900017 ER PT J AU Cromaz, M Symons, TJM Lane, GJ Lee, IY MacLeod, RW AF Cromaz, M Symons, TJM Lane, GJ Lee, IY MacLeod, RW TI Blue: a database for high-fold gamma-ray coincidence data SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE Gammasphere; Greta; high-multiplicity gamma-ray events ID BINARY SEARCH TREES AB Optimal sensitivity in large HPGe gamma -ray spectrometers such as Gammasphere and Euroball is achieved with 4-fold gamma -ray coincidences or higher. Analysis of coincidence data at these folds is difficult as storage constraints make histogram-based techniques impractical. To address the problem of efficient storage of and access to high-fold coincidence data we have developed Blue, a specialized database program. Each coincidence event in this database is stored in its native fold eliminating statistical artifacts which can be introduced by unfolding a high-fold event to several lower-fold events. Partition of the dataset is based on the density distribution of coincidence events which makes data access efficient. A simple yet flexible query system is implemented by using a tree-like index for these partitions. This program is capable of executing a variety of queries, such as taking gates on a multi-fold database, at timescales which are interactive (s) or near-interactive (min). Simple compression techniques are employed so that databases with sizes of 10(9) coincidences can easily be stored in a space of 10 Gb or less. (C) Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Cromaz, M (reprint author), Lawrence Berkeley Natl Lab, MS 88-103,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Lane, Gregory/A-7570-2011 OI Lane, Gregory/0000-0003-2244-182X NR 9 TC 61 Z9 61 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 APR 21 PY 2001 VL 462 IS 3 BP 519 EP 529 DI 10.1016/S0168-9002(00)01126-8 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435MU UT WOS:000168885900020 ER PT J AU Goodman, CD Bhattacharya, M Aufderheide, MB Bloom, SD Zupranski, P AF Goodman, CD Bhattacharya, M Aufderheide, MB Bloom, SD Zupranski, P TI Data analysis techniques for extracting Gamow-Teller strengths from 0 degrees (p,n) data SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE charge-exchange reactions; neutron time-of-flight; B(GT) ID ENERGY-LEVELS; LIGHT-NUCLEI; SCATTERING; EXCHANGE AB Techniques are described to obtain absolute normalizations for Gamow-Teller strength functions from (p,n) spectra. A method using data taken at two different proton energies and a method using polarization transfer data are discussed. Both methods require determining the number of counts due to the Fermi transition which is usually not completely resolved. We discuss methods for normalizing to unresolved Fermi peaks and handling peak shapes encountered in real time-of-flight spectra. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Indiana Univ, Cyclotron Facil, Bloomington, IN 47408 USA. Univ Washington, Nucl Phys Lab, Seattle, WA 98195 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Andrzej Soltan Inst Nucl Studies, PL-00689 Warsaw, Poland. RP Goodman, CD (reprint author), Indiana Univ, Cyclotron Facil, 2401 Milo B Sampson Lane, Bloomington, IN 47408 USA. NR 13 TC 4 Z9 4 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 APR 21 PY 2001 VL 462 IS 3 BP 545 EP 554 DI 10.1016/S0168-9002(00)01317-6 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 435MU UT WOS:000168885900023 ER PT J AU Wu, ZL Stolz, CJ Weakley, SC Hughes, JD Zhao, Q AF Wu, ZL Stolz, CJ Weakley, SC Hughes, JD Zhao, Q TI Damage threshold prediction of hafnia-silica multilayer coatings by nondestructive evaluation of fluence-limiting defects SO APPLIED OPTICS LA English DT Article ID LASER-INDUCED DAMAGE; THIN-FILM COATINGS; PHOTOTHERMAL DEFLECTION; OPTICAL COATINGS; THERMAL-CONDUCTIVITY; PROBE; SPECTROSCOPY; EVAPORATION; MICROSCOPY; MORPHOLOGY AB A variety of microscopic techniques were employed to characterize fluence-limiting defects in hafnia-silica multilayer coatings manufactured for the National Ignition Facility, a fusion laser with a wavelength of 1.053 mum and a pulse width of 3 ns. Photothermal microscopy, with the surface thermal lens effect, was used to map the absorption and thermal characteristics of 3 mm x 3 mm areas of the coatings. High-resolution subaperture scans, with a 1-mum step size and a 3-mum pump-beam diameter, were conducted on the defects to characterize their photothermal properties. Optical and atomic force microscopy were used to identify defects and characterize their topography. The defects were then irradiated by a damage testing laser (1.06 mum and 3 ns) in single-shot mode until damage occurred. The results were analyzed to determine the role of nodular and nonnodular defects in limiting the damage thresholds of the multilayer coatings. It was found that, although different types of defect were present in these coatings, the fluence-limiting ones had the highest photothermal signals (up to 126x over the host coating). The implication of this study is that coating process improvements for hafnia-silica multilayer coatings should have a broader focus than just elimination of source ejection, since high photothermal signals frequently occur at nodule-free regions. The study also demonstrates that, for optics subject to absorption-induced thermal damage, photothermal microscopy is an appropriate tool for nondestructive identification of fluence-limiting defects. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Eastern Michigan Univ, Expt Laser Phys Lab, Ypsilanti, MI 48197 USA. RP Wu, ZL (reprint author), Oplink Commun Inc, 3469 N 1st St, San Jose, CA 95134 USA. EM joew@oplink.com; stolzl@linl.gov; hughes7@llnl.gov NR 45 TC 21 Z9 25 U1 0 U2 8 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 APR 20 PY 2001 VL 40 IS 12 BP 1897 EP 1906 DI 10.1364/AO.40.001897 PG 10 WC Optics SC Optics GA 421RD UT WOS:000168076600004 PM 18357189 ER PT J AU Cha, PD de Pillis, LG AF Cha, PD de Pillis, LG TI Model updating by adding known masses SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE model updating; added masses; least squares ID MATRIX CORRECTION AB New approaches are developed that use measured data to adjust the analytical mass and stiffness matrices of a system so that the agreement between the analytical modes of vibration and the modal survey is improved. By adding known masses to the structure of interest, measuring the modes of vibration of this mass-modified system, and finally using this set of new data in conjunction with the initial modal survey, the analytical mass matrix of the structure can be corrected, after which the analytical stiffness matrix can be readily updated. By manipulating the correction matrices into vector forms, the connectivity information can be enforced, thereby preserving the physical configuration of the system and reducing the sizes of the least-squares problems that need to be solved. Solution techniques for updating the system matrices are introduced, and the numerical issues associated with solving overdetermined and underdetermined least squares problems are investigated. The effects of round-off errors are also studied, and heuristic criteria are given for determining the minimum number of modes that need to be measured in order to ensure sufficiently accurate updated mass and stiffness matrices. Numerical experiments are presented to validate the proposed model-updating techniques, to illustrate the effects of the number of measured modes on the quality of the updated model, to show how the magnitudes and locations of the added masses influence the updated matrices, and to highlight the numerical issues discussed in this paper. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Harvey Mudd Coll, Dept Engn, Claremont, CA 91711 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Harvey Mudd Coll, Dept Math, Claremont, CA 91711 USA. RP Cha, PD (reprint author), Harvey Mudd Coll, Dept Engn, Claremont, CA 91711 USA. NR 15 TC 14 Z9 22 U1 1 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD APR 20 PY 2001 VL 50 IS 11 BP 2547 EP 2571 DI 10.1002/nme.136 PG 25 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 416HD UT WOS:000167773500005 ER PT J AU Hashimoto, M Donald, CD Yannone, SM Chen, DJ Roy, R Kow, YW AF Hashimoto, M Donald, CD Yannone, SM Chen, DJ Roy, R Kow, YW TI A possible role of Ku in mediating sequential repair of closely opposed lesions SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID COLI ENDONUCLEASE-III; DEPENDENT PROTEIN-KINASE; MULTIPLY DAMAGED SITES; DOUBLE-STRAND BREAKS; ESCHERICHIA-COLI; IONIZING-RADIATION; DNA-DAMAGE; COMPLEX; ENDS; IDENTIFICATION AB One of the hallmarks of ionizing radiation exposure is the formation of clustered damage that includes closely opposed lesions. We show that the Ku70/80 complex (Ku) has a role in the repair of closely opposed lesions in DNA. DNA containing a dihydrouracil (DHU) close to an opposing single strand break was used as a model substrate. It was found that gu has no effect on the enzymatic activity of human endonuclease III when the substrate DNA contains only DHU, However, with DNA containing a DHU that is closely opposed to a single strand break, Ku inhibited the nicking activity of human endonuclease III as well as the amount of free double strand breaks induced by the enzyme, The inhibition on the formation of a free double strand break by Ku was found to be much greater than the inhibition of human endonuclease III-nicking activity by Ku, Furthermore, there was a concomitant increase in the formation of Ku-DNA complexes when endonuclease III was present. Similar results were also observed with Escherichia coli endonuclease III. These results suggest that Ku reduces the formation of endonuclease III-induced free double strand breaks by sequestering the double strand breaks formed as a Ku-DNA complex. In doing so, Ku helps to avoid the formation of the intermediary free double strand breaks, possibly helping to reduce the mutagenic event that might result from the misjoining of frank double strand breaks. C1 Emory Univ, Sch Med, Dept Radiat Oncol, Atlanta, GA 30335 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Texas, Med Branch, Sealy Ctr Mol Sci, Galveston, TX 77555 USA. RP Kow, YW (reprint author), Emory Univ, Sch Med, Dept Radiat Biol, Div Canc Biol, 145 Edgewood Ave, Atlanta, GA 30335 USA. RI Yannone, Steven/G-1927-2011 FU NCI NIH HHS [CA50519, CA80917]; NIGMS NIH HHS [GM 54163, GM37216] NR 30 TC 26 Z9 26 U1 0 U2 0 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD APR 20 PY 2001 VL 276 IS 16 BP 12827 EP 12831 DI 10.1074/jbc.M010906200 PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 423VN UT WOS:000168198600052 PM 11278783 ER PT J AU Knize, MG Kulp, KS Malfatti, MA Salmon, CP Felton, JS AF Knize, MG Kulp, KS Malfatti, MA Salmon, CP Felton, JS TI Liquid chromatography-tandem mass spectrometry method of urine analysis for determining human variation in carcinogen metabolism SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 24th International Symposium on High Performance Liquid Phase Separations and Related Techniques (HPLC 2000) CY JUN 24-30, 2000 CL SEATTLE, WASHINGTON DE amines, heterocyclic aromatic; aminomethylphenylimidazo[4,5-b]pyridine; pyridines; glucuronides ID HETEROCYCLIC AMINE CONTENT; 2-AMINO-1-METHYL-6-PHENYLIMIDAZO<4,5-B>PYRIDINE PHIP; MEAT-PRODUCTS; COOKED FOODS; CHICKEN; IDENTIFICATION; EXCRETION; PROSTATE; CANCER; RATS AB We developed a solid-phase extraction LC-MS-MS method for the analysis of the four major metabolites of PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pridine) in human urine after a meal of well-done chicken. Ten volunteers each ate either 150 or 200 g of well-done chicken breast containing 9-21 mug of PhIP. Among the individual volunteers there is 8-fold variation in the total amount of metabolites and 20-fold variation in the relative amounts of individual metabolites, showing individual differences in carcinogen metabolism. PhIP metabolites were also detected in urine from a subject consuming chicken in a restaurant meal, demonstrating the method's sensitivity after real-life exposures. Published by Elsevier Science B.V. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Knize, MG (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 5508, Livermore, CA 94550 USA. FU NCI NIH HHS [CA55861] NR 20 TC 25 Z9 26 U1 1 U2 4 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 APR 20 PY 2001 VL 914 IS 1-2 BP 95 EP 103 DI 10.1016/S0021-9673(01)00522-2 PG 9 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 423XD UT WOS:000168202300014 PM 11358237 ER PT J AU Xue, G Pang, HM Yeung, ES AF Xue, G Pang, HM Yeung, ES TI On-line nanoliter cycle sequencing reaction with capillary zone electrophoresis purification for DNA sequencing SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 24th International Symposium on High Performance Liquid Phase Separations and Related Techniques (HPLC 2000) CY JUN 24-30, 2000 CL SEATTLE, WASHINGTON DE sequencing methods; DNA ID FLUORESCENCE DETECTION; SAMPLE PREPARATION; SYSTEM AB An integrated system for DNA sequencing based on a nanoreactor for cycle-sequencing reaction coupled with on-line capillary zone electrophoresis (CZE) for purification and capillary gel electrophoresis (CGE) for separation is presented. Less than 100 nl of premixed reagent solution, which includes dye-labeled terminator pre-mix, bovine serum albumin and template, was hydrodynamically injected into a fused-silica capillary (75 mum I.D.) inside a laboratory-made microthermocycler for cycle sequencing reaction. in the same capillary, the reaction products were purified by CZE followed by on-line injection of the DNA fragments into another capillary for CGE. Over 540 base pairs (bp) of DNA can be separated and the bases called for single-standed DNA with 0.9% error rate. The total time was about 3.5 h, or a cycle time of 2 h with staggered operation. For double-stranded DNA, a longer reaction time was required and base calling up to 490 bp with 1.2% error rate was achieved. The whole system is readily adaptable to automated multiplex operation for DNA sequencing or polymerase chain reaction analysis. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA USA. RP Yeung, ES (reprint author), Iowa State Univ, Ames Lab, US DOE, 332 Wilhelm Hall, Ames, IA 50011 USA. NR 26 TC 14 Z9 15 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD APR 20 PY 2001 VL 914 IS 1-2 BP 245 EP 256 DI 10.1016/S0021-9673(00)01167-5 PG 12 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 423XD UT WOS:000168202300029 PM 11358219 ER PT J AU Shen, YF Berger, SJ Smith, RD AF Shen, YF Berger, SJ Smith, RD TI High-efficiency capillary isoelectric focusing of protein complexes from Escherichia coli cytosolic extracts SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 24th International Symposium on High Performance Liquid Phase Separations and Related Techniques (HPLC 2000) CY JUN 24-30, 2000 CL SEATTLE, WASHINGTON DE isoelectric focusing; Escherichia coli; proteins ID IONIZATION MASS-SPECTROMETRY; FIELD-FLOW FRACTIONATION; ELECTROSPRAY-IONIZATION; DISSOCIATION; DIMERIZATION; SEPARATION AB High-efficiency capillary isoelectric focusing (cIEF) separations of protein complexes obtained from soluble protein fractions are demonstrated. Size-exclusion chromatography was used as a first dimension separation to fractionate putative protein complexes with apparent molecular masses of up to 1 500 000 from an Escherichia coli cytosolic fraction. Non-denaturing cIEF separations using highly hydrophilic polymer-coated capillaries constituted the second dimension. The conditions developed produced reproducible and high-efficiency separations, corresponding to similar to2.10(6) theoretical plates and peak capacities of similar to 10(3) for pH 3-10 cIEF separations in 65 cm long capillaries. Combination of the two non-denaturing separation dimensions permitted isolation and analysis of individual protein complexes from complicated biological samples. Studies indicated that many E. coli complexes were stable on the time scale of the cIEF separations, but were degraded upon more extended periods of storage on ice, necessitating rapid sample processing and fast analysis techniques. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Box 999,Mail Stop K8-98, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 24 TC 21 Z9 21 U1 2 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 APR 20 PY 2001 VL 914 IS 1-2 BP 257 EP 264 DI 10.1016/S0021-9673(01)00579-9 PG 8 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 423XD UT WOS:000168202300030 PM 11358220 ER PT J AU Brankovic, SR McBreen, J Adzic, RR AF Brankovic, SR McBreen, J Adzic, RR TI Spontaneous deposition of Pt on the Ru(0001) surface SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article DE spontaneous deposition; metal monolayers; platinum; ruthenium; Ru(0001) ID PLATINUM-ELECTRODES; METHANOL OXIDATION; RUTHENIUM; ADSORPTION; PT(111) AB Spontaneous deposition of Pt on a Ru(0001) single crystal surface has been demonstrated by in situ scanning tunneling microscopy and linear sweep voltammetry techniques. The immersion of a ultra-high vacuum (UHV) prepared Ru single crystal in a platinum-ion-containing solution results in the formation of monolayer-to-multilayer Pt deposits without application of an external potential. The coverage and morphology of the Pt deposit depend on the concentration of platinum ions and the time of immersion. This simple method can be applied to Pt deposition on Ru nanoparticles, which can considerably reduce Pt loading in Pt/Ru electrocatalysts. The electrochemical behavior of such Pt/Ru(0001) bimetallic surfaces depends on the coverage of the Ru electrode and amount and morphology of the Pt deposit, which indicates a pronounced electronic modification of the Pt adlayer due to a strong Pt/Ru interaction. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Energy Sci & Technol Dept, Upton, NY 11973 USA. RP Adzic, RR (reprint author), Brookhaven Natl Lab, Energy Sci & Technol Dept, Upton, NY 11973 USA. NR 21 TC 119 Z9 121 U1 1 U2 26 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD APR 20 PY 2001 VL 503 IS 1-2 BP 99 EP 104 DI 10.1016/S0022-0728(01)00349-7 PG 6 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 432BE UT WOS:000168665900010 ER PT J AU Eichman, BF Mooers, BHM Alberti, M Hearst, JE Ho, PS AF Eichman, BF Mooers, BHM Alberti, M Hearst, JE Ho, PS TI The crystal structures of psoralen cross-linked DNAs: Drug-dependent formation of Holliday junctions SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE DNA-binding drug; DNA structure; Holliday junction; psoralen; recombination ID NUCLEOTIDE EXCISION-REPAIR; T7 RNA-POLYMERASE; GENETIC-RECOMBINATION; SACCHAROMYCES-CEREVISIAE; ELONGATION COMPLEXES; ESCHERICHIA-COLI; MAMMALIAN-CELLS; 4-WAY JUNCTION; DOUBLE HELIX; STRAND AB The single-crystal structures are presented for two DNA sequences with the thymine bases covalently cross-linked across the complementary strands by 4 ' -hydroxymethyl-4,5 ' ,8-trimethylpsoralen (HMT). The HMT-adduct of d(CCGCTAGCGG) forms a psoralen-induced Holliday junction, showing for the first time the effect of this important class of chemotheraputics on the structure of the recombination intermediate. In contrast, HMT-d(CCGGTACCGG) forms a sequence-dependent junction. Ln both structures, the DNA duplex is highly distorted at the thymine base linked to the six-member pyrone ring of the drug. The psoralen cross-link defines the intramolecular interactions of the drug-induced junction, while the sequence-dependent structure is nearly identical to the native Holliday junction of d(CCGGTACCGG) alone. The two structures contrast the effects of drug- and sequence-dependent interactions on the structure of a Holliday junction, suggesting a role for psoralen in the mechanism to initiate repair of psoralen-lesions in mammalian DNA. (C) 2001 Academic Press. C1 Oregon State Univ, Dept Biochem & Biophys, Corvallis, OR 97331 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Ho, PS (reprint author), Oregon State Univ, Dept Biochem & Biophys, ALS 2011, Corvallis, OR 97331 USA. RI Ho, Pui/F-6186-2014; OI Ho, Pui/0000-0002-8082-4311; Eichman, Brandt/0000-0002-0965-2297; Mooers, Blaine/0000-0001-8181-8987 FU NIEHS NIH HHS [ES00210] NR 58 TC 35 Z9 36 U1 1 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD APR 20 PY 2001 VL 308 IS 1 BP 15 EP 26 DI 10.1006/jmbi.2001.4567 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 426LT UT WOS:000168351200003 PM 11302703 ER PT J AU Lee, CM Yang, SH Mun, BJ Ross, PN AF Lee, CM Yang, SH Mun, BJ Ross, PN TI Surface structure of lithiated graphite by X-ray photoelectron diffraction SO SURFACE SCIENCE LA English DT Article DE alkali metals; graphite; photoelectron diffraction measurement; surface structure, morphology, roughness, and topography ID SCANNING-TUNNELING-MICROSCOPY; ORIENTED PYROLYTIC-GRAPHITE; INTERCALATION COMPOUNDS; LITHIUM AB The surface composition and structure of a stage-one lithium intercalation compound (U-GIC) R:ns studied by X-ray photoelectron diffraction (XPD) from Li 1s and C 1s core levels. The Li-CIC was prepared in situ by vapor phase intercalation of lithium into highly oriented pyrolitic graphite (HOPG) in an ultra-high vacuum system, Stage-one Li-GIC, LiC6, having a characteristic golden color, was obtained using hi evaporation onto a HOPG substrate at 400 K, while a metallic lithium overlayer was observed at depositions below; room temperature. XPD patterns of Li 1s and C 1s intensities as a function of the polar emission angle were obtained at a fixed photon energy of 1253.6 eV. The experimental XPD patterns oil the HOPG and the stage-one Li-GIC were both in quite good agreement with calculated XPD patterns based on Rehr-Albers separable representation for scattering of the emitted photoelectrons. The structural model for the surface of the Li-GIC producing the best fit to the experimental data has the bulk LiC6 lattice with surface termination in the graphene plane. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Ross, PN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 16 TC 12 Z9 12 U1 2 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 20 PY 2001 VL 477 IS 2-3 BP 126 EP 132 DI 10.1016/S0039-6028(00)01106-7 PG 7 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 425WK UT WOS:000168314500008 ER PT J AU Rodriguez, JA Perez, M Jirsak, T Gonzalez, L Maiti, A AF Rodriguez, JA Perez, M Jirsak, T Gonzalez, L Maiti, A TI Coadsorption of sodium and SO2 on MgO(100): alkali promoted S-O bond cleavage SO SURFACE SCIENCE LA English DT Letter DE alkali metals; density functional calculations; near edge extended X-ray absorption fine structure (NEXAFS); photoelectron spectroscopy; magnesium oxides; sulphur; sulphur dioxide; surface chemical reaction ID TOTAL-ENERGY CALCULATIONS; AB-INITIO; MOLECULAR-DYNAMICS; TIO2(110) SURFACE; OXIDE SURFACES; ADSORPTION; PHOTOEMISSION; H2S; SULFUR; MGO AB The coadsorption of Na and SO2 on MgO(100) was studied using synchrotron based high-resolution photoemission, X-ray absorption near-edge spectroscopy and first-principles density functional calculations. The adsorption of SO2 on a MgO(100) single crystal and MgO(100) films, grown epitaxially on a Mo(100) substrate, produces SO3 and SO4 species at 300 It. In general, the epitaxial films are a good model for studying the chemistry of SO2 on MgO(100). Defects and imperfections in the MgO(100) films facilitate SO4 formation, but no dissociation of SO2 is observed on the films ol MgO(100) single crystal, Dissociation of S-O bonds is seen after coadsorbing SO2 with Na on the MgO(100) surfaces. The Na adatoms provide occupied electronic states above the MgO valence band which are very efficient for bonding interactions with SO2. In the {Na + SO2)/MgO(100) system, Na transfers electrons into the lowest-unoccupied molecular orbital of SO2 inducing a weakening of the S-O bonds that facilitates dissociation of the molecule, (C) 2000 Published by Elsevier Science B.V. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Cent Univ Venezuela, Fac Ciencias, Caracas 1020A, Venezuela. Mol Simulat Inc, San Diego, CA 92121 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Bldg 555A,POB 5000, Upton, NY 11973 USA. NR 57 TC 19 Z9 19 U1 0 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 20 PY 2001 VL 477 IS 2-3 BP L279 EP L288 DI 10.1016/S0039-6028(01)00896-2 PG 10 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 425WK UT WOS:000168314500001 ER PT J AU Susan, DF Marder, AR AF Susan, DF Marder, AR TI Ni-Al composite coatings: Diffusion analysis and coating lifetime estimation SO ACTA MATERIALIA LA English DT Article DE coating; electron microprobe analysis; Ni-Al system; diffusion (bulk); kinetics ID NICKEL-ALUMINUM ALLOYS; ELECTRON-MICROSCOPY; HIGH-TEMPERATURES; COUPLE INTERFACE; DEGREES C; OXIDATION; DEGRADATION; FAILURE; GROWTH; OXIDES AB The interdiffusion of Ni matrix/Al particle composite coatings and nickel substrates was studied using electron probe microanalysis (EPMA) and a one-dimensional diffusion model. The initial coating microstructure was a two-phase mixture of gamma (Ni) and gamma (Ni3Al). The coating/substrate assemblies were aged at 800 to 1100 degreesC for times up to 2000 h. It was found that aluminum losses to the substrate are significant at 1000 degreesC and above. The experimental results fur the diffusion of Al into the substrate were compared with model predictions based on a diffusion equation for a finite layer on an infinite substrate. Using combined experimental and model results, the effects of temperature and coating thickness were determined and a rationale was developed for coating lifetime prediction. Published by Elsevier Science Ltd on behalf of Acta Materialia Inc. C1 Sandia Natl Labs, Mat Characterizat Dept, Albuquerque, NM 87185 USA. Lehigh Univ, Bethlehem, PA 18015 USA. RP Susan, DF (reprint author), Sandia Natl Labs, Mat Characterizat Dept, MS 0886,POB 5800, Albuquerque, NM 87185 USA. NR 26 TC 34 Z9 39 U1 1 U2 14 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD APR 19 PY 2001 VL 49 IS 7 BP 1153 EP 1163 DI 10.1016/S1359-6454(01)00022-2 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 422UC UT WOS:000168136800004 ER PT J AU Engler, O AF Engler, O TI Recrystallisation textures in copper-manganese alloys SO ACTA MATERIALIA LA English DT Article DE recrystallization & recovery; nucleation; growth; texture; microstructure; copper alloys ID RECRYSTALLIZATION TEXTURES; CUBE TEXTURE; ORIENTED NUCLEATION; 70-30 BRASS; ORIENTATION; ORIGIN; GROWTH; ALUMINUM; ENERGY AB Manganese is the only alloying clement that does not lower the (normalised) stacking fault energy (SFE) of copper-alloys. Therefore, analysis of the recrystallisation behaviour of Cu-Mn alloys may yield information on the impact of solute atoms on the recrystallisation, independent of the influence of the SFE. For this purpose the progress of recrystallisation is tracked in various Cu-Mn alloys by hardness measurements and X-ray texture investigations. To support the results obtained by macrotexture analysis, and in particular to trace the origin of the recrystallisation texture orientations, local orientation measurements are performed by means of electron back scattering diffraction (EBSD). The recrystallisation textures as well as data on the recrystallisation kinetics of the present Cu-Mn alloys are compared to results obtained in other binary Cu-alloys. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Mat Sci & Technol Div MST8, Los Alamos, NM 87545 USA. RP Engler, O (reprint author), VAW Aluminium AG, Res & Dev, POB 2468, D-53014 Bonn, Germany. NR 43 TC 46 Z9 47 U1 5 U2 16 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 APR 19 PY 2001 VL 49 IS 7 BP 1237 EP 1247 DI 10.1016/S1359-6454(01)00017-9 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 422UC UT WOS:000168136800011 ER PT J AU Zygmunt, SA Curtiss, LA Iton, LE AF Zygmunt, SA Curtiss, LA Iton, LE TI Protonation of an H2O dimer by a zeolitic Bronsted acid site SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID HYDROGEN-BONDED COMPLEXES; DENSITY-FUNCTIONAL THEORY; AB-INITIO CALCULATIONS; MOLECULAR ADSORPTION; WATER-ADSORPTION; CLUSTER-MODELS; H-ZSM-5; GAUSSIAN-2; IR; METHANOL AB The potential energy surface for the interaction of a water dimer with the Bronsted acid site in a zeolite represented by a Si4AlO4H13 cluster is examined using the B3LYP density functional method. Local energy minima corresponding to both neutral and ion-pair adsorption structures were located, as well as the transition state for proton transfer to the dimer. The neutral complex is more stable than the ion-pair structure by 2.9 kcal/mol.at the highest level of calculation. In all structures both ends of the adsorbed species form hydrogen bonds (H . . .O) to the zeolitic cluster. The zero point energy corrections cause the energy of the ion-pair structure to rise above that of the transition state, indicating that the ion-pair structure is not a true local energy minimum on the potential energy surface. These results reveal that, like the protonated water monomer complex, the protonated water dimer complex is a transition state for proton exchange between adjacent framework oxygen atoms in our cluster model of the zeolite. However, since the energy differences between the three structures investigated here are so small, the protonated water dimer might possibly be a true equilibrium structure for a particular zeolite framework. The calculated vibrational frequencies for the adsorbed complexes are compared with experimental infrared spectra. This comparison suggests that experimental spectra for zeolite-water systems with loadings of two or more water molecules per acid site are a superposition of features from both neutral and ion-pair-water complexes. This interpretation is consistent with the calculated energies of the two complexes. C1 Valparaiso Univ, Dept Phys & Astron, Valparaiso, IN 46383 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RP Zygmunt, SA (reprint author), Valparaiso Univ, Dept Phys & Astron, Valparaiso, IN 46383 USA. NR 29 TC 22 Z9 23 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 19 PY 2001 VL 105 IS 15 BP 3034 EP 3038 DI 10.1021/jp003469p PG 5 WC Chemistry, Physical SC Chemistry GA 424WV UT WOS:000168257700026 ER PT J AU Lu, YF Yang, Y Sellinger, A Lu, MC Huang, JM Fan, HY Haddad, R Lopez, G Burns, AR Sasaki, DY Shelnutt, J Brinker, CJ AF Lu, YF Yang, Y Sellinger, A Lu, MC Huang, JM Fan, HY Haddad, R Lopez, G Burns, AR Sasaki, DY Shelnutt, J Brinker, CJ TI Self-assembly of mesoscopically ordered chromatic polydiacetylene/silica nanocomposites SO NATURE LA English DT Article ID MESOPOROUS SILICA; FILMS; ACID; TRANSITION; NANOSTRUCTURES; COMPOSITES; LIPOSOMES; LAYER AB Nature abounds with intricate composite architectures composed of hard and soft materials synergistically intertwined to provide both useful functionality and mechanical integrity. Recent synthetic efforts to mimic such natural designs have focused on nanocomposites(1-5), prepared mainly by slow procedures like monomer or polymer infiltration of inorganic nanostructures(6,7) or sequential deposition(8,9). Here we report the self-assembly of conjugated polymer/silica nanocomposite films with hexagonal, cubic or lamellar mesoscopic order using polymerizable amphiphilic diacetylene molecules as both structure-directing agents and monomers. The self-assembly procedure is rapid and incorporates the organic monomers uniformly within a highly ordered, inorganic environment. Polymerization results in polydiacetylene/silica nanocomposites that are optically transparent and mechanically robust. Compared to ordered diacetylene-containing films prepared as Langmuir monolayers(10) or by Langmuir-Blodgett deposition(10), the nanostructured inorganic host alters the diacetylene polymerization behaviour, and the resulting nanocomposite exhibits unusual chromatic changes in response to thermal, mechanical and chemical stimuli. The inorganic framework serves to protect, stabilize, and orient the polymer, and to mediate its function. The nanocomposite architecture also provides sufficient mechanical integrity to enable integration into devices and microsystems. C1 Univ New Mexico, Ctr Microengineered Ceram, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. Sandia Natl Labs, Adv Mat Lab, Albuquerque, NM 87106 USA. RP Brinker, CJ (reprint author), Univ New Mexico, Ctr Microengineered Ceram, Albuquerque, NM 87131 USA. RI Shelnutt, John/A-9987-2009; Sellinger, Alan/C-6250-2015 OI Shelnutt, John/0000-0001-7368-582X; Sellinger, Alan/0000-0001-6705-1548 NR 32 TC 438 Z9 446 U1 17 U2 156 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 19 PY 2001 VL 410 IS 6831 BP 913 EP 917 DI 10.1038/35073544 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 423AG UT WOS:000168152300041 PM 11309612 ER PT J AU Dumitru, A Pisarski, RD AF Dumitru, A Pisarski, RD TI Event-by-event fluctuations from decay of a Polyakov loop condensate SO PHYSICS LETTERS B LA English DT Article ID HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; FINITE-TEMPERATURE; HIGH-ENERGY; PHASE-TRANSITIONS; GAUGE-THEORY; QCD; FIELD; MOMENTUM; DYNAMICS AB A model for particle production at the deconfining phase transition in QCD is developed, as the semiclassical decay of a condensate for the Polyakov loop. In such a model, generically particle production, as measured on an event-by-event basis, exhibits significant deviations from statistical behavior. (C) 2001 Published by Elsevier Science B.V. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Dumitru, A (reprint author), Columbia Univ, Dept Phys, New York, NY 10027 USA. NR 40 TC 138 Z9 139 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 19 PY 2001 VL 504 IS 4 BP 282 EP 290 DI 10.1016/S0370-2693(01)00286-6 PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 423EZ UT WOS:000168163600002 ER PT J AU Trevese, D Kron, RG Bunone, A AF Trevese, D Kron, RG Bunone, A TI Continuum variability of active galactic nuclei in the optical-ultraviolet range SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : fundamental parameters; galaxies : Seyfert; quasars general; techniques : photometric ID MULTICOLOR PHOTOMETRY; COMPLETE SAMPLE; LUMINOSITY FUNCTION; FAINT QSOS; QUASARS; OBJECTS; SELECTED-AREA-57; EMISSION; GALAXIES AB The variability of the continuum spectral energy distribution has been analyzed for a complete magnitude-limited sample of quasars in Selected Area 57, observed at two epochs in the photographic U, B-J, F, and N bands with the Mayall 4 m telescope at Kitt Peak National Observatory. Changes delta alpha of the spectral slope alpha appear correlated with brightness variations delta log f(v), indicating an average hardening of the spectrum in the bright phases. This confirms that the correlation of variability with redshift, found in a single observing band, is due to intrinsic spectral changes. The average observed delta alpha-delta log f(v) relation is consistent with the spectral change due to temperature variation of a blackbody of about 2.5 x 10(4) K. C1 Univ Rome La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Trevese, D (reprint author), Univ Rome La Sapienza, Dipartimento Fis, Piazzale Aldo Moro 2, I-00185 Rome, Italy. NR 48 TC 37 Z9 37 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 APR 18 PY 2001 VL 551 IS 1 BP 103 EP 110 DI 10.1086/320055 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 423AF UT WOS:000168152200010 ER PT J AU Pinto, PA Eastman, RG Rogers, T AF Pinto, PA Eastman, RG Rogers, T TI A test for the nature of the type Ia supernova explosion mechanism SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : theory; radiation mechanisms : thermal; supernovae : general; X-rays : stars ID CHANDRASEKHAR-MASS MODELS; LIGHT CURVES; WHITE-DWARFS; X-RAY; GAMMA-RAYS; PHYSICS; IONIZATION; ELECTRONS; EMISSION; STARS AB Currently, popular models for Type Ia supernovae (SNe Ia) fall into two general classes. The first comprises explosions of nearly pure carbon/oxygen (C/O) white dwarfs (WDs) at the Chandrasekhar limit which ignite near their centers. The second consists of lower mass C/O cores which are ignited by the detonation of an accreted surface helium layer. Explosions of the latter type produce copious Fe, Co, and Ni K alpha emission from Ni-56 and Co-56 decay in the detonated surface layers, emission which is much weaker from Chandrasekhar-mass models. The presence of this emission provides a simple and unambiguous discriminant between these two models for SNe Ia. Both mechanisms may produce 0.1-0.6 M . of Ni-56, making them bright gamma -ray line emitters. The time to maximum brightness of Ni-56 decay lines is distinctly shorter in the M < M-ch class of model (15 days) than in the M-ch model (similar to 30 days), making gamma -ray line evolution another direct test of the explosion mechanism. It should just be possible to detect K-shell emission from a sub-M-ch explosion from SNe Ia as far away as the Virgo cluster with the XMM observatory. A 1-2 m(2) X-ray telescope such as the proposed Constellation-X observatory could observe K alpha emission from M < M-ch SNe Ia in the Virgo cluster, providing not just a detection but high- accuracy flux and kinematic information. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. RP Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM ppinto@as.arizona.edu; reastman@llnl.gov; tami@ucolick.org NR 56 TC 11 Z9 11 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 APR 18 PY 2001 VL 551 IS 1 BP 231 EP 243 DI 10.1086/320059 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 423AF UT WOS:000168152200021 ER PT J AU Ulmer, MP Matz, SM Grove, JE Strickman, MS Kurfess, JD Ruderman, M Zhu, T Ho, C AF Ulmer, MP Matz, SM Grove, JE Strickman, MS Kurfess, JD Ruderman, M Zhu, T Ho, C TI Search for redshifted annihilation radiation from the crab pulsar SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : theory; pulsars : individual (Crab Pulsar) ID GAMMA-RAY; LINE AB We present new stringent upper limits to a redshifted e(+/-) annihilation radiation line from the Crab pulsar. These upper limits are based on OSSE observations that were optimized for the 400-500 keV range. We have searched for the emission over several different phase intervals of the pulsar light curve. We find no evidence for the redshifted emission at 440 keV reported by the FIGARO team. The typical 3 sigma upper limit to phase-averaged flux (i.e., the net flux from the pulsar averaged over the entire light curve) is about 2x10(-5) photons cm(-2) s(-1). This value is about a factor of 4 lower than the 3 sigma flux reported by the FIGARO team. This result places significant new constraints on some models in which positrons are flowing down toward the surface of the Crab pulsar. C1 Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. Los Alamos Sci Lab, Los Alamos, NM USA. RP Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. NR 15 TC 3 Z9 3 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 APR 18 PY 2001 VL 551 IS 1 BP 244 EP 248 DI 10.1086/320050 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 423AF UT WOS:000168152200022 ER PT J AU Lacy, M Laurent-Muehleisen, SA Ridgway, SE Becker, RH White, RL AF Lacy, M Laurent-Muehleisen, SA Ridgway, SE Becker, RH White, RL TI The radio luminosity-black hole mass correlation for quasars from the first bright quasar survey and a "unification scheme" for radio-loud and radio-quiet quasars SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; quasars : general; radio continuum : galaxies ID ACTIVE GALACTIC NUCLEI; EARLY-TYPE GALAXIES; EMISSION-LINE; ELECTROMAGNETIC EXTRACTION; OPTICAL-PROPERTIES; ENERGY; MECHANISM; OBJECTS; IMAGES; DISKS AB Several independent lines of evidence now point to a correlation between black hole mass M-bh and radio luminosity. In this Letter, we discuss the correlation for quasars from the FIRST Bright Quasar Survey (FBQS) using black hole mass estimates from H beta line widths. The FBQS objects fill in the gap between the radio-loud and radio-quiet quasars in the radio luminosity-optical luminosity plane, and we find that they fill the corresponding gap in the M-bh-radio luminosity correlation. There is thus a continuous variation of radio luminosity with M-bh, and no evidence for a "switch" at some set of critical parameter values that turns on powerful radio jets. By combining the FBQS data with that for quasars from the Palomar-Green survey, we find evidence for a dependence of radio luminosity on accretion rate relative to the Eddington limit, L/L-Edd, as well as on M-bh, consistent with the well-known radio-optical correlation for radio-loud quasars. We therefore suggest a new scheme to "unify" radio-loud and radio-quiet objects in which the radio luminosity scales proportional to M-bh(1.9+/-0.2) (L/L-Edd)(1.0) for L/L-Edd similar to0.1, with an apparently weaker accretion rate dependence at low L/L-Edd. The scatter about this relation is +/-1.1 dex and may well hide significant contributions from other physical effects, such as the black hole spin and radio source environment. C1 Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Lacy, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, POB 808,L-413, Livermore, CA 94550 USA. NR 38 TC 86 Z9 88 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 APR 18 PY 2001 VL 551 IS 1 BP L17 EP L21 DI 10.1086/319836 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 423AR UT WOS:000168153300005 ER PT J AU Stewart, FF Harrup, MK Luther, TA Orme, CJ Lash, RP AF Stewart, FF Harrup, MK Luther, TA Orme, CJ Lash, RP TI Formation of pervaporation membranes from polyphosphazenes having hydrophilic and hydrophobic pendant groups: Synthesis and characterization SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE polyphosphazenes; membranes; NMR analysis; pervaporation; hydrophilic AB A series of new polyphosphazene polymers were synthesized using three different pendant groups with the goal of probing structure-function relationships between pendant group substitution and polymer swelling/water flux through thin dense films. Formation of polymers with relative degrees of hydrophilicty was probed by varying the stoichiometry of the pendant groups attached to the phosphazene backbone: p-methoxyphenol, 2-(2-methoxyethoxy)ethanol, and o-allylphenol. The polymers in this study were characterized using NMR, thermal methods, and dilute solution light-scattering techniques. These techniques revealed that the polymers were amorphous high polymers (M-w = 10(5)-10(7)) with varying ratios of pendant groups as determined by integration of the H-1- and P-31-NMR spectra. Thin dense film membranes were solution-cast with azo-bis(cydohexane)carbonitrile included in the matrix and crosslinked using thermal initiation. (C) 2001 John Wiley & Sons, Inc. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Stewart, FF (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 25 TC 13 Z9 15 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD APR 18 PY 2001 VL 80 IS 3 BP 422 EP 431 DI 10.1002/1097-4628(20010418)80:3<422::AID-APP1115>3.0.CO;2-H PG 10 WC Polymer Science SC Polymer Science GA 406RD UT WOS:000167228200014 ER PT J AU Kolda, TG AF Kolda, TG TI Orthogonal tensor decompositions SO SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS LA English DT Article DE tensor decomposition; singular value decomposition; principal components analysis; multidimensional arrays ID PRINCIPAL COMPONENT ANALYSIS AB We explore the orthogonal decomposition of tensors ( also known as multidimensional arrays or n-way arrays) using two different definitions of orthogonality. We present numerous examples to illustrate the difficulties in understanding such decompositions. We conclude with a counterexample to a tensor extension of the Eckart-Young SVD approximation theorem by Leibovici and Sabatier [Linear Algebra Appl., 269 (1998), pp. 307-329]. C1 Sandia Natl Labs, Computat Sci & Math Res Dept, Livermore, CA 94551 USA. RP Kolda, TG (reprint author), Sandia Natl Labs, Computat Sci & Math Res Dept, Livermore, CA 94551 USA. RI Kolda, Tamara/B-1628-2009 OI Kolda, Tamara/0000-0003-4176-2493 NR 15 TC 159 Z9 161 U1 3 U2 10 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 APR 18 PY 2001 VL 23 IS 1 BP 243 EP 255 DI 10.1137/S0895479800368354 PG 13 WC Mathematics, Applied SC Mathematics GA 465WN UT WOS:000170613100013 ER PT J AU Peyton, BW AF Peyton, BW TI Minimal orderings revisited SO SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS LA English DT Article DE minimal orderings; minimal fill; LEX M algorithm; supernodes; minimum degree; nested dissection; multisection; sparse matrix computations ID ALGORITHM; ELIMINATION; FACTORIZATION AB When minimum orderings proved too difficult to deal with, Rose, Tarjan, and Lueker instead studied minimal orderings and how to compute them [SIAM J. Comput., 5 (1976), pp. 266- 283]. This paper introduces an algorithm that is capable of computing much better minimal orderings much more efficiently than the algorithm of Rose, Tarjan, and Lueker. The new insight is a way to use certain structures and concepts from modern sparse Cholesky solvers to reexpress one of the basic results of Rose, Tarjan, and Lueker. The new algorithm begins with any initial ordering and then refines it until a minimal ordering is obtained. It is simple to obtain high-quality low-cost minimal orderings by using fill-reducing heuristic orderings as initial orderings for the algorithm. We examine several such initial orderings in some detail. Our results here and previous work by others indicate that the improvements obtained over the initial heuristic orderings are relatively small because the initial orderings are minimal or nearly minimal. Nested dissection orderings provide some significant exceptions to this rule. C1 Oak Ridge Natl Lab, Computat Sci Sect, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Peyton, BW (reprint author), Oak Ridge Natl Lab, Computat Sci Sect, Div Math & Comp Sci, POB 2008,Bldg 6012, Oak Ridge, TN 37831 USA. NR 22 TC 18 Z9 18 U1 0 U2 2 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 APR 18 PY 2001 VL 23 IS 1 BP 271 EP 294 DI 10.1137/S089547989936443X PG 24 WC Mathematics, Applied SC Mathematics GA 465WN UT WOS:000170613100015 ER PT J AU Stamenkovic, V Markovic, NM AF Stamenkovic, V Markovic, NM TI Oxygen reduction and hydrogen oxidation reactions on Pt(111) and Pt(100) in solutions containing copper ions SO LANGMUIR LA English DT Article ID SINGLE-CRYSTAL SURFACES; UNDERPOTENTIAL DEPOSITION UPD; SULFURIC-ACID-SOLUTION; X-RAY-SCATTERING; ELECTROCHEMICAL DEPOSITION; PLATINUM; CU; ADSORPTION; EVOLUTION; ANIONS AB The effects of underpotentially deposited copper (Cu-upd) On the kinetics of the oxygen reduction reaction (ORR) and the hydrogen oxidation reaction (HOR) have been studied at Pt(lll) and Pt(100) surfaces in 0.05 M H2SO4 containing either Cu2+ Or mixtures of Cu2+ and Cl- ions. The results show that Cu-upd has a strong inhibiting effect on both the ORR and the HOR. The deactivation is linked to an enhanced anion adsorption on platinum atoms adjacent to Cu-upd atoms. This mechanism explains the anomalously large inhibition by a very small amount of Cu-upd. The ORR on Cu-upd-modified electrodes proceeds mostly as a 4e(-) reaction pathway with negligible solution phase peroxide formation, ca. 3%. The physical model that appears to realize this result is one in which the active sites for the adsorption of molecular O-2 are a small number of platinum islands which are created when desorption of anions takes place from Cu-upd-unmodified platinum sites. The same sites are also active centers for the HOR. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Markovic, NM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 40 TC 21 Z9 21 U1 7 U2 32 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD APR 17 PY 2001 VL 17 IS 8 BP 2388 EP 2394 DI 10.1021/la0014095 PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 422CQ UT WOS:000168100700020 ER PT J AU Haynes, JA AF Haynes, JA TI Potential influences of bond coat impurities and void growth on premature failure of EB-PVD TBCs SO SCRIPTA MATERIALIA LA English DT Article DE oxidation; intermetallic; coating; chemical vapor deposition (CVD); thermal barrier coating ID SCALE ADHESION; OXIDATION BEHAVIOR; SUPERALLOY; BENEATH; NI C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Haynes, JA (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 19 TC 30 Z9 31 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD APR 17 PY 2001 VL 44 IS 7 BP 1147 EP 1152 DI 10.1016/S1359-6462(00)00703-X PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 433DE UT WOS:000168739400023 ER PT J AU Bischof, O Kim, SH Irving, J Beresten, S Ellis, NA Campisi, J AF Bischof, O Kim, SH Irving, J Beresten, S Ellis, NA Campisi, J TI Regulation and localization of the Bloom syndrome protein in response to DNA damage SO JOURNAL OF CELL BIOLOGY LA English DT Article DE RECQ helicases; p53; ATM; nuclear matrix; homologous recombination ID ROTHMUND-THOMSON-SYNDROME; ACUTE PROMYELOCYTIC LEUKEMIA; RAD51 RECOMBINATION PROTEIN; IRRADIATED HELA-CELLS; SYNDROME GENE-PRODUCT; ESCHERICHIA-COLI; WERNERS-SYNDROME; NUCLEAR MATRIX; HOMOLOGOUS RECOMBINATION; REPLICATIVE SENESCENCE AB Bloom syndrome (BS) is an autosomal recessive disorder characterized by a high incidence of cancer and genomic instability. BLM, the protein defective in BS, is a RecQ-like helicase, presumed to function in DNA replication, recombination, or repair. BLM localizes to promyelocytic leukemia protein (PML) nuclear bodies and is expressed during late S and G2. We show, in normal human cells, that the recombination/repair proteins hRAD51 and replication protein (RP)-A assembled with BLM into a fraction of PML bodies during late S/G2. Biochemical experiments suggested that BLM resides in a nuclear matrix-bound complex in which association with hRAD51 may be direct. DNA-damaging agents that cause double strand breaks and a G2 delay induced BLM by a p53- and ataxia-telangiectasia mutated independent mechanism. This induction depended on the G2 delay, because it failed to occur when G2 was prevented or bypassed. It coincided with the appearance of foci containing BLM, PML, hRAD51 and RP-A, which resembled ionizing radiation-induced foci. After radiation, foci containing BLM and PML formed at sites of single-stranded DNA and presumptive repair in normal cells, but not in cells with defective PML. Our findings suggest that BLM is part of a dynamic nuclear matrix-based complex that requires PML and functions during G2 in undamaged cells and recombinational repair after DNA damage. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Berlex Labs Inc, Richmond, CA 94804 USA. Mem Sloan Kettering Canc Ctr, Dept Human Genet, New York, NY 10021 USA. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Mailstop 84-171, Berkeley, CA 94720 USA. FU NCI NIH HHS [R01 CA085867-01A2, R01 CA085867]; NIA NIH HHS [AG11658, R01 AG011658] NR 77 TC 199 Z9 202 U1 1 U2 4 PU ROCKEFELLER UNIV PRESS PI NEW YORK PA 1114 FIRST AVE, 4TH FL, NEW YORK, NY 10021 USA SN 0021-9525 J9 J CELL BIOL JI J. Cell Biol. PD APR 16 PY 2001 VL 153 IS 2 BP 367 EP 380 DI 10.1083/jcb.153.2.367 PG 14 WC Cell Biology SC Cell Biology GA 426FV UT WOS:000168339900013 PM 11309417 ER PT J AU Taylor, KE AF Taylor, KE TI Summarizing multiple aspects of model performance in a single diagram. SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SKILL SCORES AB A diagram has been devised that can provide a concise statistical summary of how well patterns match each other in terms of their correlation, their root-mean-square difference, and the ratio of their variances. Although the form of this diagram is general, it is especially useful in evaluating complex models, such as those used to study geophysical phenomena. Examples are given showing that the diagram can be used to summarize the relative merits of a collection of different models or to track changes in performance of a model as it is modified. Methods are suggested for indicating on these diagrams the statistical significance of apparent differences and the degree to which observational uncertainty and unforced internal variability limit the expected agreement between model-simulated and observed behaviors. The geometric relationship between the statistics plotted on the diagram also provides some guidance for devising skill scores that appropriately weight among the various measures of pattern correspondence. C1 Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94550 USA. RP Taylor, KE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, POB 808,MS L-264, Livermore, CA 94550 USA. RI Taylor, Karl/F-7290-2011; Vuichard, Nicolas/A-6629-2011 OI Taylor, Karl/0000-0002-6491-2135; NR 17 TC 1572 Z9 1643 U1 21 U2 184 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 16 PY 2001 VL 106 IS D7 BP 7183 EP 7192 DI 10.1029/2000JD900719 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 423QZ UT WOS:000168189400001 ER PT J AU Jaffe, D Anderson, T Covert, D Trost, B Danielson, J Simpson, W Blake, D Harris, J Streets, D AF Jaffe, D Anderson, T Covert, D Trost, B Danielson, J Simpson, W Blake, D Harris, J Streets, D TI Observations of ozone and related species in the northeast Pacific during the PHOBEA campaigns 1. Ground-based observations at Cheeka Peak SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID LONG-RANGE TRANSPORT; MAUNA-LOA; ASIAN EMISSIONS; CARBON-MONOXIDE; ATLANTIC REGION; UNITED-STATES; SURFACE OZONE; NOX; CO; NITRATE AB As part of the Photochemical Ozone Budget of the Eastern North Pacific Atmosphere (PHOBEA) project, we made observations of CO, O3, NOx, peroxyacetyl nitrate (PAN), nonmethane hydrocarbons (NMHC), Rn, aerosol scattering, aerosol absorption, and aerosol number density during the springs of 1997 and 1998 at the Cheeka Peak Observatory (CPO) on the western tip of Washington State. The data have been segregated to quantify the mixing ratio of these species in the Pacific marine atmosphere. However, even in these marine air masses, there are occasionally substantial enhancements of NOx and aerosols, but not CO, which we attribute to diesel exhaust from ship traffic to and from major ports in the region. The marine air masses were further classified into four categories based on 10-day back isentropic trajectories; high, mid, and low latitude and those which had crossed over the Asian industrial region. Mean marine mixing ratios in 1998 were significantly higher then the 1997 values for CO (1997 mean equal to 151, 1998 mean equal to 170 ppbv), ethane (1771, 1968 parts per trillion by volume (pptv)), and ethyne (306, 452 pptv). Also, segregation of the 1998 data by air mass origin produced smaller differences in the mixing ratios for most species when comparing different source regions. We attribute both of these results to elevated emissions associated with unusually large areas of biomass burning which took place in Indonesia and Siberia during late 1997 and 1998. The relative enhancements of CO, ethane, ethyne, and propane we observed at CPO are consistent with enhanced biomass burning and industrial sources in the spring of 1998, relative to the spring of 1997. C1 Univ Washington, Bothell, WA 98021 USA. Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Univ Alaska, Dept Chem, Fairbanks, AK 99775 USA. Univ Alaska, Inst Geophys, Fairbanks, AK 99775 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92717 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Jaffe, D (reprint author), Univ Washington, Bothell, WA 98021 USA. RI Simpson, William/I-2859-2014; OI Simpson, William/0000-0002-8596-7290; Streets, David/0000-0002-0223-1350 NR 56 TC 65 Z9 64 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 16 PY 2001 VL 106 IS D7 BP 7449 EP 7461 DI 10.1029/2000JD900636 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 423QZ UT WOS:000168189400019 ER PT J AU Ramesh, R Aggarwal, S Auciello, O AF Ramesh, R Aggarwal, S Auciello, O TI Science and technology of ferroelectric films and heterostructures for non-volatile ferroelectric memories SO MATERIALS SCIENCE & ENGINEERING R-REPORTS LA English DT Review DE ferroelectric films; heterostructures; sputter-deposition; laser ablation-deposition; metalorganic chemical vapor-deposition; microstructure; properties; non-volatile ferroelectric memories ID CHEMICAL-VAPOR-DEPOSITION; SRBI2TA2O9 THIN-FILMS; LOW-TEMPERATURE GROWTH; ELECTRICAL-PROPERTIES; SUPERCONDUCTING ELECTRONICS; NONVOLATILE MEMORIES; INDUCED DEGRADATION; DIFFUSION-BARRIERS; SPUTTER-DEPOSITION; TI)O-3 CAPACITORS AB We present in this article a review of the status of thin film ferroelectric materials for nonvolatile memories. Key materials issues relevant to the integration of these materials on Si wafers are discussed. The effect of film microstructure and electrode defect chemistry on the ferroelectric properties relevant to a high density nonvolatile memory technology are discussed. The second part of this review focuses on approaches to integrate these capacitor structures on a filled poly-Si plug which is a critical requirement for a high density memory technology. Finally, the use of novel surface probes to study and understand broadband polarization dynamics in ferroelectric thin films is also presented. (C) 2001 Published by Elsevier Science B.V. C1 Univ Maryland, Mat Res Sci & Engn Ctr, College Pk, MD 20742 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Ramesh, R (reprint author), Univ Maryland, Mat Res Sci & Engn Ctr, College Pk, MD 20742 USA. NR 117 TC 206 Z9 223 U1 4 U2 58 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0927-796X J9 MAT SCI ENG R JI Mater. Sci. Eng. R-Rep. PD APR 16 PY 2001 VL 32 IS 6 BP 191 EP 236 DI 10.1016/S0927-796X(00)00032-2 PG 46 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 436ZQ UT WOS:000168966100001 ER PT J AU Jaffe, AH Ade, PAR Balbi, A Bock, JJ Bond, JR Borrill, J Boscaleri, A Coble, K Crill, BP de Bernardis, P Farese, P Ferreira, PG Ganga, K Giacometti, M Hanany, S Hivon, E Hristov, VV Iacoangeli, A Lange, AE Lee, AT Martinis, L Masi, S Mauskopf, PD Melchiorri, A Montroy, T Netterfield, CB Oh, S Pascale, E Piacentini, F Pogosyan, D Prunet, S Rabii, B Rao, S Richards, PL Romeo, G Ruhl, JE Scaramuzzi, F Sforna, D Smoot, GF Stompor, R Winant, CD Wu, JHP AF Jaffe, AH Ade, PAR Balbi, A Bock, JJ Bond, JR Borrill, J Boscaleri, A Coble, K Crill, BP de Bernardis, P Farese, P Ferreira, PG Ganga, K Giacometti, M Hanany, S Hivon, E Hristov, VV Iacoangeli, A Lange, AE Lee, AT Martinis, L Masi, S Mauskopf, PD Melchiorri, A Montroy, T Netterfield, CB Oh, S Pascale, E Piacentini, F Pogosyan, D Prunet, S Rabii, B Rao, S Richards, PL Romeo, G Ruhl, JE Scaramuzzi, F Sforna, D Smoot, GF Stompor, R Winant, CD Wu, JHP TI Cosmology from MAXIMA-1, BOOMERANG, and COBE DMR cosmic microwave background observations SO PHYSICAL REVIEW LETTERS LA English DT Article ID HUBBLE CONSTANT; POWER SPECTRUM; NUCLEOSYNTHESIS; UNIVERSE; CONSTRAINTS; PARAMETERS; SUPERNOVAE; RADIATION; SCALE AB Recent results from BOOMERANG-98 and MAXIMA-1, taken together with COBE DMR, provide consistent and high signal-to-noise measurements of the cosmic microwave background power spectrum at spherical harmonic multipole bands over 2 < l 800. Analysis of the combined data yields 68% (95%) confidence limits on the total density, Omega (tot) similar or equal to 1.11 +/- 0.07 ((+0.13)(-0.12)), the baryon density, Omega (b)h(2) similar or equal to 0.032(-0.004+)(0.005) ((+0.009)(-0.008)), and the scalar spectral tilt, n(s) similar or equal to 1.01(-0.07)(+0.09) ((+0.17)(-0.14)). These data are consistent with inflationary initial conditions for structure formation. Taken together with other cosmological observations, they imply the existence of both nonbaryonic dark matter and dark energy in the Universe. C1 Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Queen Mary Univ London, London E1 4NS, England. Univ Roma Tor Vergata, Dipartimento Fis, I-00173 Rome, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. IROE, CNR, Florence, Italy. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. CALTECH, Pasadena, CA 91125 USA. Univ Roma La Sapienza, Dipartimento Fis, Rome, Italy. Univ Oxford, Astrophys, NAPL, Oxford OX2 6HT, England. Inst Super Tecn, CENTRA, Lisbon, Portugal. Coll France, F-75231 Paris 05, France. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. ENEA Ctr Ric Frascati, I-00044 Frascati, Italy. Univ Wales Coll Cardiff, Cardiff CF24 3YB, S Glam, Wales. Univ Toronto, Dept Phys & Astron, Toronto, ON M5S 3H8, Canada. Ist Nazl Geofis, Rome, Italy. Copernicus Astron Ctr, Warsaw, Poland. RP Jaffe, AH (reprint author), Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. RI Jaffe, Andrew/D-3526-2009; Piacentini, Francesco/E-7234-2010; OI WU, JIUN-HUEI/0000-0001-9608-7662; ROMEO, Giovanni/0000-0002-5535-7803; Hivon, Eric/0000-0003-1880-2733; Piacentini, Francesco/0000-0002-5444-9327; Masi, Silvia/0000-0001-5105-1439; de Bernardis, Paolo/0000-0001-6547-6446 NR 32 TC 416 Z9 416 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 APR 16 PY 2001 VL 86 IS 16 BP 3475 EP 3479 DI 10.1103/PhysRevLett.86.3475 PG 5 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800005 PM 11328002 ER PT J AU Chankowski, PH Ioannisian, AN Pokorski, S Valle, JWF AF Chankowski, PH Ioannisian, AN Pokorski, S Valle, JWF TI Neutrino unification SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUASI-DIRAC NEUTRINOS; DOUBLE-BETA-DECAY; MAJORANA NEUTRINOS; ELECTRON-NEUTRINO; GAUGE-THEORIES; MASSES; DEGENERATE; RATIO; RENORMALIZATION; OSCILLATIONS AB Present neutrino data are consistent with neutrino masses arising from a common seed at some "neutrino unification" scale M-X. Such a simple theoretical ansatz naturally lends to quasidegenerate neutrinos that could lie in the electron-volt range with neutrino mass splittings induced by renormalization effects associated with supersymmetric thresholds. In such a scheme the leptonic analog of the Cabibbo angle theta (circle dot) describing solar neutrino oscillations is nearly maximal. Its exact value is correlated with the smallness of theta (reactor). The two leading mass-eigenstate neutrinos present in nu (e) form a pseudo-Dirac neutrino, avoiding conflict with neutrinoless double beta decay. C1 Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. Univ Valencia, Inst Fis Corpuscular, CSIC, Edifico Inst Paterna, Valencia 46071, Spain. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Chankowski, PH (reprint author), Univ Warsaw, Inst Theoret Phys, Ul Hoza 69, PL-00681 Warsaw, Poland. RI Valle, Jose W.F./F-7573-2013 OI Valle, Jose W.F./0000-0002-1881-5094 NR 47 TC 55 Z9 55 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 16 PY 2001 VL 86 IS 16 BP 3488 EP 3491 DI 10.1103/PhysRevLett.86.3488 PG 4 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800008 PM 11328005 ER PT J AU Wang, XN Gyulassy, M AF Wang, XN Gyulassy, M TI Energy and centrality dependence of rapidity densities at RHIC energies SO PHYSICAL REVIEW LETTERS LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; CHARGED-PARTICLE MULTIPLICITY; HEAVY-ION COLLISIONS; HADRONIC REACTIONS; DISTRIBUTIONS; QUARK AB The energy and centrality dependence of the charged multiplicity per participant nucleon is shown to he able to differentiate between final state saturation and fixed scale perturbative QCD models of initial entropy production in high-energy heavy-ion collisions. The energy dependence is shown to test the nuclear enhancement of the minijet component of the initial conditions, while the centrality dependence provides a key test of whether gluon saturation is reached at RHIC energies. The HIJING model predicts that the rapidity density per participant increases with centrality while the saturation model prediction is essentially independent of centrality. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. RP Wang, XN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Mailstop 70-319, Berkeley, CA 94720 USA. OI Wang, Xin-Nian/0000-0002-9734-9967 NR 27 TC 109 Z9 111 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 APR 16 PY 2001 VL 86 IS 16 BP 3496 EP 3499 DI 10.1103/PhysRevLett.86.3496 PG 4 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800010 PM 11328007 ER PT J AU Adcox, K Adler, SS Ajitanand, NN Akiba, Y Alexander, J Aphecetche, L Arai, Y Aronson, SH Averbeck, R Awes, TC Barish, KN Barnes, PD Barrette, J Bassalleck, B Bathe, S Baublis, V Bazilevsky, A Belikov, S Bellaiche, FG Belyaev, ST Bennett, MJ Berdnikov, Y Botelho, S Brooks, ML Brown, DS Bruner, N Bucher, D Buesching, H Bumazhnov, V Bunce, G Burward-Hoy, J Butsyk, S Carey, TA Chand, P Chang, J Chang, WC Chavez, LL Chernichenko, S Chi, CY Chiba, J Chiu, M Choudhury, RK Christ, T Chujo, T Chung, MS Chung, P Cianciolo, V Cole, BA D'Enterria, DG David, G Delagrange, H Denisov, A Deshpande, A Desmond, EJ Dietzsch, O Dinesh, BV Drees, A Durum, A Dutta, D Ebisu, K Efremenko, YV El Chenawi, K En'yo, H Esumi, S Ewell, L Ferdousi, T Fields, DE Fokin, SL Fraenkel, Z Franz, A Frawley, AD Fung, SY Garpman, S Ghosh, TK Glenn, A Godoi, AL Goto, Y Greene, SV Perdekamp, MG Gupta, SK Guryn, W Gustafsson, HA Haggerty, JS Hamagaki, H Hansen, AG Hara, H Hartouni, EP Hayano, R Hayashi, N He, X Hemmick, TK Heuser, J Hibino, M Hill, JC Ho, DS Homma, K Hong, B Hoover, A Ichihara, T Imai, K Ippolitov, MS Ishihara, M Jacak, BV Jang, WY Jia, J Johnson, BM Johnson, SC Joo, KS Kametani, S Kang, JH Kam, M Kapoor, SS Kelly, S Khachaturov, B Khanzadeev, A Kikuchi, J Kim, DJ Kim, HJ Kim, SY Kim, YG Kinnison, WW Kistenev, E Kiyomichi, A Klein-Boesing, C Klinksiek, S Kochenda, L Kochetkov, D Kochetkov, V Koehler, D Kohama, T Kozlov, A Kroon, PJ Kurita, K Kweon, MJ Kwon, Y Kyle, GS Lacey, R Lajoie, JG Lauret, J Lebedev, A Lee, DM Leitch, MJ Li, XH Li, Z Lim, DJ Liu, MX Liu, X Liu, Z Maguire, CF Mahon, J Makdisi, YI Manko, VI Mao, Y Mark, SK Markacs, S Martinez, G Marx, MD Masaike, A Matathias, F Matsumoto, T McGaughey, PL Melnikov, E Merschmeyer, M Messer, F Messer, M Miake, Y Miller, TE Milov, A Mioduszewski, S Mischke, RE Mishra, GC Mitchell, JT Mohanty, AK Morrison, DP Moss, JM Muhlbacher, F Muniruzzaman, M Murata, J Nagamiya, S Nagasaka, Y Nagle, JL Nakada, Y Nandi, BK Newby, J Nikkinen, L Nilsson, P Nishimura, S Nyanin, AS Nystrand, J O'Brien, E Ogilvie, CA Ohnishi, H Ojha, ID Ono, M Onuchin, V Oskarsson, A Osterman, L Otterlund, I Oyama, K Paffrath, L Palounek, APT Pantuev, VS Papavassiliou, V Pate, SF Peitzmann, T Petridis, AN Pinkenburg, C Pisani, RP Pitukhin, P Plasil, F Pollack, M Pope, K Purschke, ML Ravinovich, I Read, KF Reygers, K Riabov, V Riabov, Y Rosati, M Rose, AA Ryu, SS Saito, N Sakaguchi, A Sakaguchi, T Sako, H Sakuma, T Samsonov, V Sangster, TC Santo, R Sato, HD Sato, S Sawada, S Schlei, BR Schutz, Y Semenov, V Seto, R Shea, TK Shein, I Shibata, TA Shigaki, K Shiina, T Shin, YH Sibiriak, IG Silvermyr, D Sim, KS Simon-Gillo, J Singh, CP Singh, V Sivertz, M Soldatov, A Soltz, RA Sorensen, S Stankus, PW Starinsky, N Steinberg, P Stenlund, E Ster, A Stoll, SP Sugioka, M Sugitate, T Sullivan, JP Sumi, Y Sun, Z Suzuki, M Takagui, EM Taketani, A Tamai, M Tanaka, KH Tanaka, Y Taniguchi, E Tannenbaum, MJ Thomas, J Thomas, JH Thomas, TL Tian, W Tojo, J Torii, H Towell, RS Tserruya, I Tsuruoka, H Tsvetkov, AA Tuli, SK Tydesjo, H Tyurin, N Ushiroda, T van Hecke, HW Velissaris, C Velkovska, J Velkovsky, M Vinogradov, AA Volkov, MA Vorobyov, A Vznuzdnev, E Wang, H Watanabe, Y White, SN Witzig, C Wohn, FK Woody, CL Xie, W Yagi, K Yokkaichi, S Young, GR Yushmanov, IE Zajc, WA Zhang, Z Zhou, S AF Adcox, K Adler, SS Ajitanand, NN Akiba, Y Alexander, J Aphecetche, L Arai, Y Aronson, SH Averbeck, R Awes, TC Barish, KN Barnes, PD Barrette, J Bassalleck, B Bathe, S Baublis, V Bazilevsky, A Belikov, S Bellaiche, FG Belyaev, ST Bennett, MJ Berdnikov, Y Botelho, S Brooks, ML Brown, DS Bruner, N Bucher, D Buesching, H Bumazhnov, V Bunce, G Burward-Hoy, J Butsyk, S Carey, TA Chand, P Chang, J Chang, WC Chavez, LL Chernichenko, S Chi, CY Chiba, J Chiu, M Choudhury, RK Christ, T Chujo, T Chung, MS Chung, P Cianciolo, V Cole, BA D'Enterria, DG David, G Delagrange, H Denisov, A Deshpande, A Desmond, EJ Dietzsch, O Dinesh, BV Drees, A Durum, A Dutta, D Ebisu, K Efremenko, YV El Chenawi, K En'yo, H Esumi, S Ewell, L Ferdousi, T Fields, DE Fokin, SL Fraenkel, Z Franz, A Frawley, AD Fung, SY Garpman, S Ghosh, TK Glenn, A Godoi, AL Goto, Y Greene, SV Perdekamp, MG Gupta, SK Guryn, W Gustafsson, HA Haggerty, JS Hamagaki, H Hansen, AG Hara, H Hartouni, EP Hayano, R Hayashi, N He, X Hemmick, TK Heuser, J Hibino, M Hill, JC Ho, DS Homma, K Hong, B Hoover, A Ichihara, T Imai, K Ippolitov, MS Ishihara, M Jacak, BV Jang, WY Jia, J Johnson, BM Johnson, SC Joo, KS Kametani, S Kang, JH Kam, M Kapoor, SS Kelly, S Khachaturov, B Khanzadeev, A Kikuchi, J Kim, DJ Kim, HJ Kim, SY Kim, YG Kinnison, WW Kistenev, E Kiyomichi, A Klein-Boesing, C Klinksiek, S Kochenda, L Kochetkov, D Kochetkov, V Koehler, D Kohama, T Kozlov, A Kroon, PJ Kurita, K Kweon, MJ Kwon, Y Kyle, GS Lacey, R Lajoie, JG Lauret, J Lebedev, A Lee, DM Leitch, MJ Li, XH Li, Z Lim, DJ Liu, MX Liu, X Liu, Z Maguire, CF Mahon, J Makdisi, YI Manko, VI Mao, Y Mark, SK Markacs, S Martinez, G Marx, MD Masaike, A Matathias, F Matsumoto, T McGaughey, PL Melnikov, E Merschmeyer, M Messer, F Messer, M Miake, Y Miller, TE Milov, A Mioduszewski, S Mischke, RE Mishra, GC Mitchell, JT Mohanty, AK Morrison, DP Moss, JM Muhlbacher, F Muniruzzaman, M Murata, J Nagamiya, S Nagasaka, Y Nagle, JL Nakada, Y Nandi, BK Newby, J Nikkinen, L Nilsson, P Nishimura, S Nyanin, AS Nystrand, J O'Brien, E Ogilvie, CA Ohnishi, H Ojha, ID Ono, M Onuchin, V Oskarsson, A Osterman, L Otterlund, I Oyama, K Paffrath, L Palounek, APT Pantuev, VS Papavassiliou, V Pate, SF Peitzmann, T Petridis, AN Pinkenburg, C Pisani, RP Pitukhin, P Plasil, F Pollack, M Pope, K Purschke, ML Ravinovich, I Read, KF Reygers, K Riabov, V Riabov, Y Rosati, M Rose, AA Ryu, SS Saito, N Sakaguchi, A Sakaguchi, T Sako, H Sakuma, T Samsonov, V Sangster, TC Santo, R Sato, HD Sato, S Sawada, S Schlei, BR Schutz, Y Semenov, V Seto, R Shea, TK Shein, I Shibata, TA Shigaki, K Shiina, T Shin, YH Sibiriak, IG Silvermyr, D Sim, KS Simon-Gillo, J Singh, CP Singh, V Sivertz, M Soldatov, A Soltz, RA Sorensen, S Stankus, PW Starinsky, N Steinberg, P Stenlund, E Ster, A Stoll, SP Sugioka, M Sugitate, T Sullivan, JP Sumi, Y Sun, Z Suzuki, M Takagui, EM Taketani, A Tamai, M Tanaka, KH Tanaka, Y Taniguchi, E Tannenbaum, MJ Thomas, J Thomas, JH Thomas, TL Tian, W Tojo, J Torii, H Towell, RS Tserruya, I Tsuruoka, H Tsvetkov, AA Tuli, SK Tydesjo, H Tyurin, N Ushiroda, T van Hecke, HW Velissaris, C Velkovska, J Velkovsky, M Vinogradov, AA Volkov, MA Vorobyov, A Vznuzdnev, E Wang, H Watanabe, Y White, SN Witzig, C Wohn, FK Woody, CL Xie, W Yagi, K Yokkaichi, S Young, GR Yushmanov, IE Zajc, WA Zhang, Z Zhou, S CA PHENIX Collaboration TI Centrality dependence of charged particle multiplicity in Au-Au collisions at root(S)NN=130 GeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHENIX; ENERGIES; DETECTOR; SYSTEM AB We present results for the charged-particle multiplicity distribution at midrapidity in Au-Au collisions at roots(NN) = 130 GeV measured with the PHENIX detector at RHIC. For the 5% most central collisions we find dN(ch)/d eta (|eta =0) = 622 +/- 1(stat) +/- 41(syst). The results, analyzed as a function of centrality show a steady rise of the particle density per participating nucleon with centrality. C1 Vanderbilt Univ, Nashville, TN 37235 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Bhabha Atom Res Ctr, Bombay 400085, Maharashtra, India. Brookhaven Natl Lab, Upton, NY 11973 USA. Banaras Hindu Univ, Dept Phys, Varanasi 221005, Uttar Pradesh, India. Univ Calif Riverside, Riverside, CA 92521 USA. Chian Inst Atom Energy, Beijing, Peoples R China. Univ Tokyo, Grad Sch Sci, Ctr Nucl Study, Tokyo 1130033, Japan. Columbia Univ, New York, NY 10027 USA. Nevis Lab, New York, NY USA. Florida State Univ, Tallahassee, FL 32306 USA. Georgia State Univ, Atlanta, GA 30303 USA. Hiroshima Univ, Higashihiroshima 7398526, Japan. Inst High Energy Phys, Protvino, Russia. Iowa State Univ, Ames, IA 50011 USA. KEK, High Energy Accelerator Res Org, Ibaraki, Osaka, Japan. Korea Univ, Seoul 136701, South Korea. Kurashov Inst, Russell Res Ctr, Moscow, Russia. Kyoto Univ, Kyoto 606, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Lund, Dept Phys, SE-21100 Lund, Sweden. McGill Univ, Quebec City, PQ H3A 28T, Canada. Univ Munster, Inst Kernphys, D-48149 Munster, Germany. Myongji Univ, Kyonggido, South Korea. Nagasaki Inst Appl Sci, Nagasaki 8510193, Japan. Univ New Mexico, Albuquerque, NM USA. New Mexico State Univ, Las Cruces, NM 88003 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Petersburg Nucl Phys Inst, PNPI, Gatchina, Russia. RIKEN, Inst Phys & Chem Res, Wako, Saitama 35101, Japan. Brookhaven Natl Lab, RIKEN BNL, Cent Res, Upton, NY 11973 USA. Univ Fed Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, Brazil. Univ Nantes, Ecole Mines Nantes, SUBATECH, F-20722 Nantes 3, France. St Petersburg State Tech Univ, St Petersburg, Russia. Univ Tennessee, Knoxville, TN 37996 USA. Tokyo Inst Technol, Dept Phys, Tokyo 1528551, Japan. Univ Tokyo, Tokyo 106, Japan. Univ Tsukuba, Inst Phys, Tsukuba, Ibaraki 305, Japan. Waseda Univ, Adv Res Inst Sci & Engn, Shinjuku Ku, Tokyo 162, Japan. Weizmann Inst Sci, IL-76100 Rehovot, Israel. Yonsei Univ, Seoul 120749, South Korea. KFKI Res Inst Praticle & Nucl Phys, Budapest, Hungary. RP Adcox, K (reprint author), Vanderbilt Univ, 221 Kirkland Hall, Nashville, TN 37235 USA. RI Taketani, Atsushi/E-1803-2017; seto, richard/G-8467-2011; Semenov, Vitaliy/E-9584-2017; Peitzmann, Thomas/K-2206-2012; En'yo, Hideto/B-2440-2015; Hayano, Ryugo/F-7889-2012; HAMAGAKI, HIDEKI/G-4899-2014; Durum, Artur/C-3027-2014; Yokkaichi, Satoshi/C-6215-2017 OI Taketani, Atsushi/0000-0002-4776-2315; Peitzmann, Thomas/0000-0002-7116-899X; Hayano, Ryugo/0000-0002-1214-7806; NR 18 TC 250 Z9 249 U1 6 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 16 PY 2001 VL 86 IS 16 BP 3500 EP 3505 DI 10.1103/PhysRevLett.86.3500 PG 6 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800011 PM 11328008 ER PT J AU Weitzel, KM Jarvis, GK Malow, M Baer, T Song, Y Ng, CY AF Weitzel, KM Jarvis, GK Malow, M Baer, T Song, Y Ng, CY TI Observation of accurate ion dissociation thresholds in pulsed field ionization-photoelectron studies SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHOTOION COINCIDENCE SPECTROSCOPY; FLIGHT SELECTION SCHEME; HIGH-RESOLUTION; SYNCHROTRON-RADIATION; DYNAMICS; O-2 AB We report the first observation, together with a mechanism far such an observation, of a steplike feature in the pulsed field ionization photoelectron measurement of CH4(C2H2), marking the 0 K dissociation threshold for the formation of CH3+ + H(C2H+ + H) from CH4(C2H2) The nonexistence of a step in the spectrum for C2H4 at its dissociation threshold for C2H2+ formation provides strong support for the proposed mechanism. This experiment shows that, for a range of molecules, where the ion dissociation lifetimes near the dissociation thresholds are <10(-7) s, pulsed field ionization photoelectron measurements will yield not only highly accurate ionization energies, but also 0 K dissociation thresholds. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Freie Univ Berlin, Inst Chem & Physikal & Theoret Chem, D-14195 Berlin, Germany. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Ng, CY (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. NR 19 TC 28 Z9 28 U1 1 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 APR 16 PY 2001 VL 86 IS 16 BP 3526 EP 3529 DI 10.1103/PhysRevLett.86.3526 PG 4 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800017 PM 11328014 ER PT J AU Zudov, MA Ponomarev, IV Efros, AL Du, RR Simmons, JA Reno, JL AF Zudov, MA Ponomarev, IV Efros, AL Du, RR Simmons, JA Reno, JL TI New class of magnetoresistance oscillations: Interaction of a two-dimensional electron gas with leaky interface phonons SO PHYSICAL REVIEW LETTERS LA English DT Article ID GAAS AB We report on a new class of magnetoresistance oscillations observed in a high-mobility two-dimensional electron gas (2DEG) in GaAs-AlxGa1-xAs heterostructures. Appearing in a weak magnetic field (B < 0.3 T) and only in a narrow temperature range (2 K < T < 9 K), these oscillations are periodic in 1/B with a frequency proportional to the electron Fermi wave vector, k(F). We interpret the effect as a magnetophonon resonance of the 2DEG with leaky interface-acoustic phonon modes carrying a wave vector q = 2k(F). Calculations show a few branches of such modes existing on the GaAs-AlxGa1-xAs interface, and their velocities are in quantitative agreement with the observation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. RP Zudov, MA (reprint author), Stanford Univ, Free Electron Laser Ctr, Stanford, CA 94305 USA. RI Zudov, Michael/A-3013-2008; Ponomarev, Ilya/F-5183-2010 OI Ponomarev, Ilya/0000-0002-8584-6034 NR 14 TC 75 Z9 76 U1 2 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 APR 16 PY 2001 VL 86 IS 16 BP 3614 EP 3617 DI 10.1103/PhysRevLett.86.3614 PG 4 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800039 PM 11328036 ER PT J AU Wang, YM Fuhrer, MS Zettl, A Ooi, S Tamegai, T AF Wang, YM Fuhrer, MS Zettl, A Ooi, S Tamegai, T TI New vortex-matter size effect observed in Bi2Sr2CaCu2O8+delta SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; MAGNETIC-RELAXATION; II SUPERCONDUCTORS; FLUX-PENETRATION; PHASE-DIAGRAM; CRYSTALS; BARRIERS; PEAK; LATTICES; LINE AB The vortex-matter 3D to 2D phase transition is studied in micron-sized Bi2Sr2CaCu2O8+delta single crystals using local Hall magnetization measurements. At a given temperature, the second magnetization peak, the signature of a possible 3D-2D vortex phase transition, disappears for samples smaller than a critical length. We suggest that this critical length should be equated with the 2D vortex lattice ah-plane correlation length R-c(2D). The magnitude and temperature dependence of R-c(2D) agree well with Larkin-Ovchinnikov collective pinning theory. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 1138656, Japan. RP Zettl, A (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Fuhrer, Michael/E-7634-2010; Tamegai, Tsuyoshi /C-6656-2011; Zettl, Alex/O-4925-2016 OI Fuhrer, Michael/0000-0001-6183-2773; Zettl, Alex/0000-0001-6330-136X NR 26 TC 14 Z9 14 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 16 PY 2001 VL 86 IS 16 BP 3626 EP 3629 DI 10.1103/PhysRevLett.86.3626 PG 4 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800042 PM 11328039 ER PT J AU Montgomery, DS AF Montgomery, DS TI Comment on "First observation of ion acoustic waves produced by the Langmuir decay instability" SO PHYSICAL REVIEW LETTERS LA English DT Editorial Material ID LASER HOT-SPOTS; SATURATION C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Montgomery, DS (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. OI Montgomery, David/0000-0002-2355-6242 NR 3 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 16 PY 2001 VL 86 IS 16 BP 3686 EP 3686 DI 10.1103/PhysRevLett.86.3686 PG 1 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800057 PM 11328054 ER PT J AU Pesme, D Huller, S Laval, G Depierreux, S Fuchs, J Labaune, C Michard, A Baldis, H AF Pesme, D Huller, S Laval, G Depierreux, S Fuchs, J Labaune, C Michard, A Baldis, H TI Comment on "First observation of ion acoustic waves produced by the Langmuir decay instability" - Reply SO PHYSICAL REVIEW LETTERS LA English DT Editorial Material C1 Ecole Polytech, Ctr Phys Theor, F-91128 Palaiseau, France. Ecole Polytech, Lab Utilisat Lasers Intenses, F-91128 Palaiseau, France. Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA USA. RP Pesme, D (reprint author), Ecole Polytech, Ctr Phys Theor, F-91128 Palaiseau, France. NR 3 TC 3 Z9 3 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 16 PY 2001 VL 86 IS 16 BP 3687 EP 3687 DI 10.1103/PhysRevLett.86.3687 PG 1 WC Physics, Multidisciplinary SC Physics GA 422GH UT WOS:000168109800058 ER PT J AU Jolly, MS Rosa, R Temam, R AF Jolly, MS Rosa, R Temam, R TI Accurate computations on inertial manifolds SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE computation of inertial manifolds; approximate inertial manifolds; Kuramoto-Sivashinsky equation ID KURAMOTO-SIVASHINSKY EQUATION; INVARIANT-MANIFOLDS; DYNAMICAL PROPERTIES; NONLINEAR STABILITY; GALERKIN METHOD; INTERFACES; DIMENSION; FAMILIES; SYSTEMS AB An algorithm is implemented for the computation of inertial manifolds to arbitrary accuracy. It is applied to the Kuramoto-Sivashinsky equation to recover the high wave number components of elements on the global attractor. The computational results demonstrate that this algorithm is significantly more accurate than previous methods, when compared after just a few iterations. An essential feature of the algorithm is that it does not require that the entire manifold be constructed. Hence the algorithm is particularly suited for computing trajectories on the manifold, and its computational complexity is independent of the dimension. C1 Indiana Univ, Dept Math, Bloomington, IN 47405 USA. Univ Fed Rio de Janeiro, Inst Matemat, BR-21945970 Rio De Janeiro, Brazil. Univ Paris 11, Anal Numer Lab, F-91405 Orsay, France. Indiana Univ, Inst Appl Math & Sci Comp, Bloomington, IN 47405 USA. Univ Minnesota, Inst Math & Its Applicat, Minneapolis, MN 55455 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Jolly, MS (reprint author), Indiana Univ, Dept Math, Rawles Hall, Bloomington, IN 47405 USA. NR 53 TC 7 Z9 7 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PD APR 16 PY 2001 VL 22 IS 6 BP 2216 EP 2238 DI 10.1137/S1064827599351738 PG 23 WC Mathematics, Applied SC Mathematics GA 430RB UT WOS:000168588400018 ER PT J AU Huber, VJ Dietz, ML AF Huber, VJ Dietz, ML TI Improved conditions for the addition of alkoxides to di(ethylene glycol) di-p-tosylate: application to the stereospecific synthesis of the trans-isomers of dicyclohexano-18-crown-6 SO TETRAHEDRON LETTERS LA English DT Article DE crown ether; stereospecific synthesis ID MACROCYCLE INTERACTION; KINETIC DATA; RECOGNITION BEHAVIOR; CROWN-ETHERS; EXTRACTION; CATIONS; ANIONS AB Conditions are defined for the efficient preparation of polyethers by direct condensation of ditosylates and alkoxides, and this approach is shown to provide a facile method for the synthesis of the trans-syn-trans (C) and trans-anti-trans (D) isomers of dicyclohexano-18-crown-6 (DCH18C6), one which both provides significantly improved yields and avoids the difficult separations required by certain previously described synthetic methods. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Huber, VJ (reprint author), Molecumet Ltd, 2023 120th Ave NE, Bellevue, WA 98005 USA. NR 21 TC 6 Z9 6 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4039 J9 TETRAHEDRON LETT JI Tetrahedron Lett. PD APR 16 PY 2001 VL 42 IS 16 BP 2945 EP 2948 DI 10.1016/S0040-4039(01)00331-8 PG 4 WC Chemistry, Organic SC Chemistry GA 421EJ UT WOS:000168048900005 ER PT J AU Tang, KQ Lin, YH Matson, DW Kim, T Smith, RD AF Tang, KQ Lin, YH Matson, DW Kim, T Smith, RD TI Generation of multiple electrosprays using microfabricated emitter arrays for improved mass spectrometric sensitivity SO ANALYTICAL CHEMISTRY LA English DT Article ID TAYLOR CONES; FABRICATION; MICRODEVICE; IONIZATION; PRINCIPLES; INTERFACE; DEVICES AB Arrays of microelectrospray emitters were fabricated on polycarbonate, substrates using a laser etching technique. Stable multielectrosprays were successfully generated in the liquid flow rate range relevant to mass spectrometric applications, Comparison of electrosprays generated from the microfabricated emitter array and conventional fused-silica capillaries showed similar spray characteristics and reliability. Higher total electrospray ion currents were observed as the number of electrosprays increased at a given total liquid flow rate. Consistent with the theoretical prediction, the total spray current at a constant total liquid flow rate was shown experimentally to be approximately proportional to the square root of the number of electrosprays. It is further projected that when total flow rate is optimized the maximum achievable total current will be proportional to the number of emitters. Evaluation of the multielectrospray device using a triple quadrupole mass spectrometer showed a factor of 2-3 sensitivity enhancement for the spray numbers ranging from two to nine compared to a conventional single electrospray ionization source under the same operating conditions. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Lin, Yuehe/D-9762-2011; Smith, Richard/J-3664-2012 OI Lin, Yuehe/0000-0003-3791-7587; Smith, Richard/0000-0002-2381-2349 FU NCRR NIH HHS [RR12365] NR 22 TC 110 Z9 110 U1 1 U2 25 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 APR 15 PY 2001 VL 73 IS 8 BP 1658 EP 1663 DI 10.1021/ac001191r PG 6 WC Chemistry, Analytical SC Chemistry GA 423BY UT WOS:000168156600002 PM 11338576 ER PT J AU Lazar, IM Ramsey, RS Ramsey, JM AF Lazar, IM Ramsey, RS Ramsey, JM TI On-chip proteolytic digestion and analysis using "wrong-way-round" electrospray time-of-flight mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID RAPID PROTEIN IDENTIFICATION; MICROFABRICATED DEVICE; LIQUID-CHROMATOGRAPHY; POLYACRYLAMIDE GELS; TRYPTIC DIGESTS; POSITIVE-ION; DEAD VOLUME; IONIZATION; MICROCHIP; HEMOGLOBIN AB Rapid protein digestion and analysis using a hybrid microchip nanoelectrospray device and time-of-flight mass spectrometry detection are reported. The device consists of a planar glass chip with microfabricated channels coupled to a disposable nanospray emitter. Reactions between substrate and enzyme (trypsin), mixed off-chip and then immediately loaded into a sample reservoir on the device, are monitored in real time following the onset of electrospray, Protein cleavage products are determined at the optimum pH for generating tryptic fragments, directly from the digestion buffer using "wrong-way-round" electrospray, i.e., monitoring (MH)(+) ions from basic solutions. Intense tryptic peptide ions are observed within a few minutes following sample loading on the microchip. Proteins were identified from low femtomole or even attomole quantities of analyte/spectrum using peptide mass fingerprinting, loading 0.1-2 pmol/muL of sample on the chip. The sequence coverage for analyzed proteins ranged from 70 to 95%. The rapid analysis of human hemoglobin is demonstrated using the technique. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Ramsey, JM (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. OI Lazar, Iulia/0000-0001-7746-7889 FU NCI NIH HHS [IR33CA83238] NR 52 TC 89 Z9 93 U1 3 U2 14 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 APR 15 PY 2001 VL 73 IS 8 BP 1733 EP 1739 DI 10.1021/ac001420+ PG 7 WC Chemistry, Analytical SC Chemistry GA 423BY UT WOS:000168156600012 PM 11338586 ER PT J AU Shen, YF Zhao, R Belov, ME Conrads, TP Anderson, GA Tang, KQ Pasa-Tolic, L Veenstra, TD Lipton, MS Udseth, HR Smith, RD AF Shen, YF Zhao, R Belov, ME Conrads, TP Anderson, GA Tang, KQ Pasa-Tolic, L Veenstra, TD Lipton, MS Udseth, HR Smith, RD TI Packed capillary reversed-phase liquid chromatography with high-performance electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry for proteomics SO ANALYTICAL CHEMISTRY LA English DT Article ID 2-DIMENSIONAL GEL-ELECTROPHORESIS; PROTEIN IDENTIFICATION; MIXTURES; COLUMNS; ISOTACHOPHORESIS; TECHNOLOGIES; PEPTIDES; UTILITY; TAGS AB In this study, high-efficiency packed capillary reversed-phase liquid chromatography (RPLC) coupled on-line with high-performance Fourier transform ion cyclotron resonance (FTICR) mass spectrometry has been investigated for the characterization of complex cellular proteolytic digests. Long capillary columns (80-cm) packed with small (3-mum) C18 bonded particles provided a total peak capacity of similar to 1000 for cellular proteolytic polypeptides when interfaced with an ESI-FTICR mass spectrometer under composition gradient conditions at a pressure of 10 000 psi, Large quantities of cellular proteolytic digests (e.g,, 500 mug) could be loaded onto packed capillaries of 150-mum inner diameter without a significant loss of separation efficiency. Precolumns with suitable inner diameters were found useful for improving the elution reproducibility without a significant loss of separation quality. Porous particle packed capillaries were found to provide better results than those containing nonporous particles because of their higher sample capacity. Two-dimensional analyses from the combination of packed capillary RPLC with high-resolution FTICR yield a combined capacity for separations of >1 million polypeptide components and simultaneously provided information for the identification of the separated components based upon the accurate mass tag concept previously described. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 FU NCI NIH HHS [CA81654] NR 44 TC 207 Z9 211 U1 2 U2 43 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 APR 15 PY 2001 VL 73 IS 8 BP 1766 EP 1775 DI 10.1021/ac0011336 PG 10 WC Chemistry, Analytical SC Chemistry GA 423BY UT WOS:000168156600016 PM 11338590 ER PT J AU Wei, W Yeung, ES AF Wei, W Yeung, ES TI DNA capillary electrophoresis in entangled dynamic polymers of surfactant molecules SO ANALYTICAL CHEMISTRY LA English DT Article ID REPLACEABLE LINEAR POLYACRYLAMIDE; NONIONIC SURFACTANTS; POLY(VINYLPYRROLIDONE) SOLUTION; POLY(ETHYLENE OXIDE); ELEVATED-TEMPERATURE; GEL-ELECTROPHORESIS; MICELLAR SOLUTIONS; WORMLIKE MICELLES; AQUEOUS-SOLUTIONS; SEPARATION AB Aqueous solutions of monomeric nonionic surfactants, n-alkyl polyoxyethylene ethers (C16E6, C16E8, C14E6), can be used as sieving matrixes for the separation of DNA fragments by capillary electrophoresis, Unlike ordinary polymer solutions, these surfactant solutions behave as dynamic polymers. By combining the "reversible gel" theory of DNA electrophoresis and the static and dynamic properties of wormlike surfactant micelles, a model is developed for describing the migration behavior of DNA molecules in these solutions. According to the model, the separation limit can be extended at low surfactant concentrations. Surfactant solutions as a separation medium provide many advantages over ordinary polymers, such as ease of preparation, solution homogeneity, stable structure, low viscosity, and self-coating property for reducing electroosmotic now. More importantly, the properties of wormlike micelles (micelle size, entanglement concentration) can be adjusted by simply changing the monomer concentration, denaturant, and temperature to allow the separation of different size ranges of DNA fragments. Fast separation is achieved for DNA fragments ranging from 10 bp to 5 kb by using bare fused-silica columns. DNA sequencing fragments of BigDye G-labeled M13 up to 600 bases were separated within 60 min. C1 Iowa State Univ Sci & Technol, Ames Lab, US DOE, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Iowa State Univ Sci & Technol, Ames Lab, US DOE, Ames, IA 50011 USA. NR 48 TC 43 Z9 44 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 EI 1520-6882 J9 ANAL CHEM JI Anal. Chem. PD APR 15 PY 2001 VL 73 IS 8 BP 1776 EP 1783 DI 10.1021/ac0012997 PG 8 WC Chemistry, Analytical SC Chemistry GA 423BY UT WOS:000168156600017 PM 11338591 ER PT J AU Jasinski, J Swider, W Liliental-Weber, Z Visconti, P Jones, KM Reshchikov, MA Yun, F Morkoc, H Park, SS Lee, KY AF Jasinski, J Swider, W Liliental-Weber, Z Visconti, P Jones, KM Reshchikov, MA Yun, F Morkoc, H Park, SS Lee, KY TI Characterization of free-standing hydride vapor phase epitaxy GaN SO APPLIED PHYSICS LETTERS LA English DT Article ID GALLIUM; NITRIDE AB A free-standing GaN template grown by hydride vapor phase epitaxy has: been characterized by transmission electron microscopy (TEM). The TEM investigation was augmented by x-ray diffraction, defect delineation etching process followed by imaging with atomic force microscopy and variable temperature photoluminescence. The density of dislocations near the N face was determined to be, in order, 3 +/- 1 X 10(7), 4 +/- 1 x 10(7), and about 1 X 10(7) cm(-2) by cross-sectional TEM, plan-view TEM, and a defect revealing etch, respectively. The same methods on the Ga face revealed the defect concentration to be, in order, less than 1 X 10(7) cm(-2) by plan-view TEM, less than 5 x 10(6) cm(-2) by cross-sectional TEM, and 5 X 10(5) cm(-2) by defect revealing hot H3PO4 acid, respectively. The full width at half maximum of the symmetric (0002) x-ray diffraction peak was 69 and 160 are sec for the Ga and N faces, respectively. That for the asymmetric (10(1) over bar4) peak was 103 and 140 are sec for Ga and N faces, respectively. The donor bound exciton linewidth was about 1 meV each at 10 K, and a green band centered at about 2.44 eV was observed. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. Virginia Commonwealth Univ, Dept Phys, Richmond, VA 23284 USA. Samsung Adv Inst Technol, Suwon 440600, South Korea. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. CNR, Ist Studio Nuovi Mat Elettron, I-73100 Lecce, Italy. RP Jasinski, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012; VISCONTI, PAOLO/L-7214-2015 OI VISCONTI, PAOLO/0000-0002-4058-4042 NR 14 TC 51 Z9 51 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 15 PY 2001 VL 78 IS 16 BP 2297 EP 2299 DI 10.1063/1.1359779 PG 3 WC Physics, Applied SC Physics GA 425EK UT WOS:000168275200011 ER PT J AU Anuntalabhochai, S Chandej, R Phanchaisri, B Yu, LD Vilaithong, T Brown, IG AF Anuntalabhochai, S Chandej, R Phanchaisri, B Yu, LD Vilaithong, T Brown, IG TI Ion-beam-induced deoxyribose nucleic acid transfer SO APPLIED PHYSICS LETTERS LA English DT Article ID PHYSICAL-MECHANISMS; IMPLANTATION AB We report our observations of the interaction of energetic ions with bacterial cells, inducing direct deoxyribose nucleic acid (DNA) transfer into Escherichia coli (E. coli). Argon- and nitrogen-ion beams were used to bombard the bacteria E. coli in a vacuum with energy of 26 keV and fluence in the range 0.5-4x10(15) ions/cm(2). Three DNA plasmids, pGEM2. pGEM-T easy, and pGFP, carrying different marker genes, were subsequently transferred (separately) into the appropriately ion-bombarded bacteria and successfully expressed. The results of this study indicate that ion beams with an energy such that the ion range is approximately equal to the cell envelope thickness, at a certain range of fluence, are able to generate pathways for macromolecule transfer through the envelope without irreversible damage. (C) 2001 American Institute of Physics. C1 Chiang Mai Univ, Fac Sci, Dept Biol, Chiang Mai 50200, Thailand. Inst Sci & Technol Res & Dev, Chiang Mai 50202, Thailand. Chiang Mai Univ, Fac Sci, Fast Neutron Res Facil, Dept Phys, Chiang Mai 50200, Thailand. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Anuntalabhochai, S (reprint author), Chiang Mai Univ, Fac Sci, Dept Biol, Chiang Mai 50200, Thailand. NR 18 TC 44 Z9 48 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 15 PY 2001 VL 78 IS 16 BP 2393 EP 2395 DI 10.1063/1.1362338 PG 3 WC Physics, Applied SC Physics GA 425EK UT WOS:000168275200043 ER PT J AU Voegelin, A Vulava, VM Kretzschmar, R AF Voegelin, A Vulava, VM Kretzschmar, R TI Reaction-based model describing competitive sorption and transport of Cd, Zn, and Ni in an acidic soil SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID METAL-ION BINDING; ORGANIC-MATTER; CONTAMINATED SOILS; CADMIUM SORPTION; SANDY SOIL; PH; CALCIUM; COEFFICIENTS; EXCHANGE; KINETICS AB Predicting the mobility of heavy metals in soils requires models that accurately describe metal adsorption in the presence of competing cations. They should also be easily adjustable to specific soil materials and applicable in reactive transport codes. In this study, Cd adsorption to an acidic soil material was investigated over a wide concentration range (10(-8) to 10(-2) M CdCl2) in the presence of different background electrolytes (10(-4) to 10(-2) M CaCl2 or MgCl2 or 0.05 to 0.5 M NaCl). The adsorption experiments were conducted at pH values between 4.6 and 6.5. A reaction-based sorption model was developed using a combination of nonspecific cation exchange reactions and competitive sorption reactions to sites with high affinity for heavy metals. This combined cation exchange/specific sorption (CESS) model accurately described the entire Cd sorption data set. Coupled to a solute transport code, the model accurately predicted Cd breakthrough curves obtained in column transport experiments. The model was further extended to describe competitive sorption and transport of Cd, Zn, and Ni. At pH 4.6, both Zn and Ni exhibited similar sorption and transport behavior as observed for Cd. In all transport experiments conducted under acidic conditions, heavy metal adsorption was shown to be reversible and kinetic effects were negligible within time periods ranging from hours up to four weeks. C1 Swiss Fed Inst Technol, Inst Terr Ecol, CH-8952 Schlieren, Switzerland. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Kretzschmar, R (reprint author), Swiss Fed Inst Technol, Inst Terr Ecol, Grabenstr 3, CH-8952 Schlieren, Switzerland. RI Voegelin, Andreas/B-4018-2009; Kretzschmar, Ruben/B-4579-2016 OI Voegelin, Andreas/0000-0003-2873-8966; Kretzschmar, Ruben/0000-0003-2587-2430 NR 45 TC 59 Z9 61 U1 3 U2 30 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 APR 15 PY 2001 VL 35 IS 8 BP 1651 EP 1657 DI 10.1021/es0001106 PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 422BX UT WOS:000168099000015 PM 11329716 ER PT J AU Acierno, JS Kennedy, JC Falardeau, JL Leyne, M Bromley, MC Colman, MW Sun, M Bove, C Ashworth, LK Chadwick, LH Schiripo, T Ma, S Goldin, E Schiffmann, R Slaugenhaupt, SA AF Acierno, JS Kennedy, JC Falardeau, JL Leyne, M Bromley, MC Colman, MW Sun, M Bove, C Ashworth, LK Chadwick, LH Schiripo, T Ma, S Goldin, E Schiffmann, R Slaugenhaupt, SA TI A physical and transcript map of the MCOLN1 gene region on human chromosome 19p13.3-p13.2 SO GENOMICS LA English DT Article ID MUCOLIPIDOSIS TYPE-IV; MUTATIONS; 19P; IDENTIFICATION; FAMILIES; LOCUS; DISEASE AB Mutations in IMCOLN1 have been found to cause mucolipidosis type IV (MLIV; MIM 252650), a rare autosomal recessive lysosomal storage disorder found primarily in the Ashkenazi Jewish population. As a part of the successful cloning of MCOLN1, we constructed a 1.4-Mb physical map containing 14 BACs and 4 cosmids that encompasses the region surrounding MCOLN1 on human chromosome 19p13.3-p13.2-a region to which linkage or association has been reported for multiple diseases. Here we detail the precise physical mapping of 28 expressed sequence tags that represent unique UniGene clusters, of which 15 are known genes. We present a detailed transcript map of the MCOLN1 gene region that includes the genes KIAA0521, neuropathy target esterase (NTE), a novel zinc finger gene, and two novel transcripts in addition to MCOLN1. We also report the identification of eight new polymorphic markers between D19S406 and D19S912, which allowed us to pinpoint the location of MCOLN1 by haplotype analysis and which will facilitate future fine-mapping in this region, Additionally, we briefly describe the correlation between the observed haplotypes and the mutations found in MCOLN1. The complete 14-marker haplotypes of non-Jewish disease chromosomes, which are crucial for the genetic diagnosis of MLIV in the non-Jewish population, are presented here for the first time. (C) 2001 Academic Press. C1 Harvard Univ, Inst Human Genet, Sch Med, Boston, MA 02115 USA. Massachusetts Gen Hosp, Mol Neurogenet Unit, Charlestown, MA 02129 USA. NINDS, Dev & Metab Neurol Branch, NIH, Bethesda, MD 20892 USA. Univ Calif Lawrence Livermore Natl Lab, Human Genome Ctr, Livermore, CA 94550 USA. RP Slaugenhaupt, SA (reprint author), Harvard Univ, Inst Human Genet, Sch Med, HIM Bldg,Room 422,77 Ave Louis Pasteur, Boston, MA 02115 USA. FU NINDS NIH HHS [R01-NS39945] NR 23 TC 6 Z9 7 U1 0 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD APR 15 PY 2001 VL 73 IS 2 BP 203 EP 210 DI 10.1006/geno.2001.6526 PG 8 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 428DU UT WOS:000168446700008 PM 11318610 ER PT J AU Nelson, PW Mittler, JE Perelson, AS AF Nelson, PW Mittler, JE Perelson, AS TI Effect of drug efficacy and the eclipse phase of the viral life cycle on estimates of HIV viral dynamic parameters SO JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES LA English DT Article DE HIV-HIV pathogenesis; mathematical modeling; viral dynamics ID HUMAN-IMMUNODEFICIENCY-VIRUS; ACTIVE ANTIRETROVIRAL THERAPY; FOLLICULAR DENDRITIC CELLS; MATHEMATICAL-ANALYSIS; INTRACELLULAR DELAY; IN-VIVO; TYPE-1 INFECTION; CLEARANCE RATE; DECAY-RATES; TRANSCRIPTION AB Fits of mathematic models to the decline in HIV-1 RNA after antiretroviral therapies have yielded estimates for the life span of productively infected cells of 1 to 2 days. In a previous report, we described the mathematic properties of an extended model that accounts for imperfect viral suppression and the eclipse phase of the viral life cycle (the intracellular delay between initial infection and release of progeny virions). In this article, we fit this extended model to detailed data on the decline of plasma HIV-1 RNA after treatment with the protease inhibitor ritonavir. Because the therapy in this study was most likely not completely suppressive, we allowed the drug efficacy parameter to vary from 70% to 100%. Estimates for the clearance rate of free virus, c, increased with the addition of the intracellular delay (as reported previously) but were not appreciably affected by changes in the drug efficacy parameter. By contrast, the estimated death rate of virus-producing cells, delta, increased from an average of 0.49 day(-1) to 0.90 day(-1) (an increase of 84%) because the drug efficacy parameter was reduced from 100% to 70%. Neglecting the intracellular delay, the comparable increase in delta was only about 55%. The inferred increases in delta doubled when the model was extended to account for possible increases in target cell densities after treatment initiation. This work suggests that estimates for delta may be greater than previously reported and that the half-life of a cell in vivo that is producing virus, on average, may be 1 day. C1 Univ Calif Los Alamos Natl Lab, Theoret Biol & Biophys Grp, Los Alamos, NM 87545 USA. Univ Michigan, Dept Math, Ann Arbor, MI 48109 USA. RP Perelson, AS (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Biol & Biophys Grp, MS-K710,T-10, Los Alamos, NM 87545 USA. FU NCRR NIH HHS [RR-00166, RR06555] NR 37 TC 51 Z9 53 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1525-4135 J9 J ACQ IMMUN DEF SYND JI J. Acquir. Immune Defic. Syndr. PD APR 15 PY 2001 VL 26 IS 5 BP 405 EP 412 PG 8 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 433QP UT WOS:000168771500002 PM 11391159 ER PT J AU Petersen, GA Myers, SM AF Petersen, GA Myers, SM TI Copper gettering by aluminum precipitates in aluminum-implanted silicon SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID AL; SI AB Copper in Si is shown to be strongly gettered by Al-rich precipitates formed by implanting Al to supersaturation and then annealing. At temperatures ranging from 600 to 800 degreesC a layer containing Al precipitates is found to getter Cu from Cu silicide located on the opposite side of a 0.25 mm Si wafer, indicating a substantially lower chemical potential for the Cu in the molten-Al phase. Cu gettering proceeds rapidly until an atomic ratio of approximately 2 Cu atoms to 1 Al atom is reached in the precipitated Al region, after which the gettering process slows down. Redistribution of Cu from one Al-rich layer to another at low Cu concentrations demonstrates that a segregation-type gettering mechanism is operating. Cu gettering occurs primarily in the region containing the precipitated Al rather than in the region where the Al is entirely substitutional. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Petersen, GA (reprint author), Intel Corp, RR5-230,4100 Sara Rd, Rio Rancho, NM 87124 USA. NR 21 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2001 VL 89 IS 8 BP 4269 EP 4274 DI 10.1063/1.1353557 PG 6 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500009 ER PT J AU Gao, F Weber, WJ AF Gao, F Weber, WJ TI Computer simulation of disordering and amorphization by Si and Au recoils in 3C-SiC SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID IRRADIATION-INDUCED AMORPHIZATION; SILICON-CARBIDE; AMORPHOUS TRANSITION; INDUCED CRYSTALLINE; MOLECULAR-DYNAMICS; SINGLE-CRYSTALS; ACCUMULATION; DAMAGE; RECOVERY; CERAMICS AB Molecular dynamics has been employed to study the disordering and amorphization processes in SiC irradiated with Si and Au ions. The large disordered domains, consisting of interstitials and antisite defects, are created in the cascades produced by Au primary knock-on atoms (PKAs); whereas Si PKAs generate only small interstitial clusters, with most defects being single interstitials and vacancies distributed over a large region. No evidence of amorphization is found at the end of the cascades created by Si recoils. However, the structure analysis indicates that the large disordered domains generated by Au recoils can be defined as an amorphous cluster lacking long-range order. The driving force for amorphization in this material is due to the local accumulation of Frenkel pairs and antisite defects. These results are in good agreement with experimental evidence, i.e., the observed higher disordering rate and the residual disorder after annealing for irradiation with Au2+ are associated with a higher probability for the in-cascade amorphization or formation of a large disordered cluster. (C) 2001 American Institute of Physics. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gao, F (reprint author), Pacific NW Natl Lab, MS K8-93,POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; Gao, Fei/H-3045-2012 OI Weber, William/0000-0002-9017-7365; NR 32 TC 59 Z9 60 U1 1 U2 17 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2001 VL 89 IS 8 BP 4275 EP 4281 DI 10.1063/1.1355717 PG 7 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500010 ER PT J AU McHugo, SA Thompson, AC Mohammed, A Lamble, G Perichaud, I Martinuzzi, S Werner, M Rinio, M Koch, W Hoefs, HU Haessler, C AF McHugo, SA Thompson, AC Mohammed, A Lamble, G Perichaud, I Martinuzzi, S Werner, M Rinio, M Koch, W Hoefs, HU Haessler, C TI Nanometer-scale metal precipitates in multicrystalline silicon solar cells SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID NEAR-EDGE STRUCTURE; POLYCRYSTALLINE SILICON; DIFFUSION LENGTH; RECOMBINATION ACTIVITY; MISFIT DISLOCATIONS; GROWN SILICON; IMPURITIES; PHOSPHORUS; FE; DEFECTS AB In this study, we have utilized characterization methods to identify the nature of metal impurity precipitates in low performance regions of multicrystalline silicon solar cells. Specifically, we have utilized synchrotron-based x-ray fluorescence and x-ray absorption spectromicroscopy to study the elemental and chemical nature of these impurity precipitates, respectively. We have detected nanometer-scale precipitates of Fe, Cr, Ni, Cu, and Au in multicrystalline silicon materials from a variety of solar cell manufacturers. Additionally, we have obtained a direct correlation between the impurity precipitates and regions of low light-induced current, providing direct proof that metal impurities play a significant role in the performance of multicrystalline silicon solar cells. Furthermore, we have identified the chemical state of iron precipitates in the low-performance regions. These results indicate that the iron precipitates are in the form of oxide or silicate compound. These compounds are highly stable and cannot be removed with standard silicon processing, indicating remediation efforts via impurity removal need to be improved. Future improvements to multicrystalline silicon solar cell performance can be best obtained by inhibiting oxygen and metal impurity introduction as well as modifying thermal treatments during crystal growth to avoid oxide or silicate formation (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Marseille, Lab Photoelect Semicond, F-13397 Marseille 20, France. Max Planck Inst Microstruct Phys, D-06120 Halle, Germany. TU Bergakad Freiberg, Inst Expt Phys, D-09596 Freiberg, Germany. Bayer AG, Cent Res, Phys, D-47812 Krefeld, Germany. RP McHugo, SA (reprint author), Agilent Technol, 350 W Trimble Rd,MS 90 UB, San Jose, CA 95131 USA. RI Perichaud, Isabelle/A-3763-2015 NR 37 TC 49 Z9 49 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2001 VL 89 IS 8 BP 4282 EP 4288 DI 10.1063/1.1330552 PG 7 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500011 ER PT J AU Spanakis, E Stratakis, E Tzanetakis, P Wang, Q AF Spanakis, E Stratakis, E Tzanetakis, P Wang, Q TI Elastic properties, intrinsic and photoinduced stress in hydrogenated amorphous-silicon thin films with different hydrogen content SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID A-SI-H; STRUCTURAL-CHANGES; MOLECULAR-HYDROGEN; METASTABILITY; DEPOSITION; NETWORK; STAEBLER; QUALITY AB All device-quality hydrogenated amorphous-silicon (a-Si:H) thin films on a substrate exhibit intrinsic compressive stress, induced primarily during growth. Furthermore, it has been established by several previous studies that exposure to intense light at room temperature leads to increase of the compressive stress in addition to the creation of dangling-bond defects, well known as the Staebler-Wronski effect [D. L. Staebler and C. R. Wronski, Appl. Phys. Lett. 31, 292 (1977)]. We present here the results of our investigation of the intrinsic and photoinduced stress as well as the Young's modulus of a series of samples with different hydrogen content prepared by hot-wire (HW) chemical-vapor deposition. These film properties have been measured with high sensitivity through the bending and flexural oscillation of crystalline silicon microcantilevers upon which we deposited the a-Si:H films. The intrinsic stress decreases with H content in the series. This result complements other investigations linking the saturated defect density to H content in HW samples and validates the generally observed correlation between stress and device performance. The photoinduced stress shows almost an identical initial increase with illumination time in all samples but tends to saturate to a lower value for the lower H concentration. We discuss our results on the variation of the Young's modulus with H content together with those of a previous study by a different measurement technique and sample growth method and compare both to theoretical calculations. A unified picture emerges clearly suggesting that the microstructure of device quality material is not homogeneous. (C) 2001 American Institute of Physics. C1 FORTH, Inst Elect Struct & Laser, GR-71110 Iraklion, Crete, Greece. Univ Crete, Dept Phys, GR-71003 Iraklion, Crete, Greece. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP FORTH, Inst Elect Struct & Laser, POB 1527, GR-71110 Iraklion, Crete, Greece. EM tzaneta@physics.uoc.gr RI Tzanetakis, Panagiotis/G-8493-2011; Spanakis, Emmanuel/F-8988-2014; Stratakis, Emmanuel/B-5365-2011 OI Stratakis, Emmanuel/0000-0002-1908-8618 NR 44 TC 25 Z9 25 U1 2 U2 10 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 APR 15 PY 2001 VL 89 IS 8 BP 4294 EP 4300 DI 10.1063/1.1353807 PG 7 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500013 ER PT J AU Jadwisienczak, WM Lozykowski, HJ Berishev, I Bensaoula, A Brown, IG AF Jadwisienczak, WM Lozykowski, HJ Berishev, I Bensaoula, A Brown, IG TI Visible emission from AlN doped with Eu and Tb ions SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MONTE-CARLO CODE; THIN-FILMS; C-LANGUAGE; GAN; LUMINESCENCE; CATHODOLUMINESCENCE; PHOTOLUMINESCENCE; CASINO AB We report the observation of visible cathodoluminescence (CL) from AlN thin films grown on sapphire (0001) substrate by molecular beam epitaxy and doped by implantation with Eu3+ and Tb3+ ions. The strongest rare earth (RE) CL was observed from samples annealed at 1100 degreesC for 0.5 h in N-2 ambient. The sharp characteristic emission lines corresponding to Eu3+ and Tb3+ intra-4f(n) shell transitions are resolved in the spectral range from 350 to 900 nm. The CL spectra were recorded over 1-16 keV electron energy in the temperature range of 8-330 K. The depth resolved CL spectral analysis gives the luminescence surface a dead layer thickness of similar to 16 nm for implanted AlN samples. We observed several different recombination centers luminescing in the 286-480 nm spectral region due to the presence of structural defects and oxygen impurities. The time resolved spectra and the CL kinetics were studied. The decay times for D-5(0)--> F-7(2) (Eu3+), D-5(3)--> F-7(5) (Tb3+), and D-5(4)--> F-7(6) (Tb3+) transitions at 300 K are similar to0.4, similar to0.9, and similar to0.4 ms, respectively. We also discuss possible excitation mechanisms of RE ions in AlN. (C) 2001 American Institute of Physics. C1 Ohio Univ, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. Univ Houston, Nitride Mat & Devices Lab, Houston, TX 77204 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Jadwisienczak, WM (reprint author), Ohio Univ, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. NR 23 TC 72 Z9 75 U1 10 U2 22 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2001 VL 89 IS 8 BP 4384 EP 4390 DI 10.1063/1.1357467 PG 7 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500026 ER PT J AU Spruytte, SG Coldren, CW Harris, JS Wampler, W Krispin, P Ploog, K Larson, MC AF Spruytte, SG Coldren, CW Harris, JS Wampler, W Krispin, P Ploog, K Larson, MC TI Incorporation of nitrogen in nitride-arsenides: Origin of improved luminescence efficiency after anneal SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GAINNAS; LASERS; GROWTH; GAAS AB A key to the utilization of nitride-arsenides for long wavelength optoelectronic devices is obtaining low defect materials with long nonradiative lifetimes. Currently, these materials must be annealed to obtain device quality material. The likely defect responsible for the low luminescence efficiency is associated with excess nitrogen. Photoluminescence and capacitance-voltage measurements indicate the presence of a trap associated with excess nitrogen which decreases in concentration upon anneal. Our films are grown by elemental source molecular beam epitaxy and the background impurity concentration is low, thus we have investigated the role of crystalline defects. High resolution x-ray diffraction showed improved crystal quality after anneal. We observed that the lattice parameter does not decrease linearly with nitrogen concentration for levels of nitrogen above 2.9 mol % GaN. The fact that Vegard's law is not observed, despite theoretical calculations that it should, indicates that nitrogen incorporates in locations other than the group V lattice sites. X-ray photoelectron spectroscopy revealed that nitrogen exists in two bonding configurations in not-annealed material: a Ga-N bond and another nitrogen complex in which N is less strongly bonded to gallium atoms. Annealing removes this second nitrogen complex. A combined nuclear reaction analysis and channeling technique showed that not annealed GaNAs contains a significant concentration of interstitial nitrogen that disappears upon anneal. We believe that this interstitial nitrogen is responsible for the deviation from Vegard's law and the low luminescence efficiency of not annealed GaNAs and GaInNAs quantum wells. (C) 2001 American Institute of Physics. C1 Stanford Univ, Solid State & Photon Lab, Stanford, CA 94305 USA. Sandia Natl Labs, Radiat Solid Interact & Proc Dept 1111, Albuquerque, NM 87185 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Spruytte, SG (reprint author), Stanford Univ, Solid State & Photon Lab, Stanford, CA 94305 USA. NR 21 TC 216 Z9 218 U1 2 U2 24 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2001 VL 89 IS 8 BP 4401 EP 4406 DI 10.1063/1.1352675 PG 6 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500028 ER PT J AU Wu, X Asher, S Levi, DH King, DE Yan, Y Gessert, TA Sheldon, P AF Wu, X Asher, S Levi, DH King, DE Yan, Y Gessert, TA Sheldon, P TI Interdiffusion of CdS and Zn2SnO4 layers and its application in CdS/CdTe polycrystalline thin-film solar cells SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TRANSPARENT CONDUCTING OXIDES; DEVICES AB In this work, we found that the interdiffusion of the CdS and Zn2SnO4 (ZTO) layers can occur either at high temperature (550-650 degreesC) in Ar or at lower temperature (400-420 degreesC) in a CdCl2 atmosphere. By integrating a Zn2SnO4 film into a CdS/CdTe solar cell as a buffer layer, this interdiffusion feature can solve several critical issues and improve device performance and reproducibility of both SnO2-based and Cd2SnO4-based CdTe cells. Interdiffusion consumes the CdS film from both the ZTO and CdTe sides during the device fabrication process and improves quantum efficiency at short wavelengths. The ZTO film acts as a Zn source to alloy with the CdS film, which results in increases in the band gap of the window layer and in short-circuit current density J(sc). Interdiffusion can also significantly improve device adhesion after CdCl2 treatment, thus providing much greater process latitude when optimizing the CdCl2 process step. The optimum CdCl2-treated CdTe device has high quantum efficiency at long wavelength, because of its good junction properties and well-passivated CdTe film. We have fabricated a Cd2SnO4/Zn2SnO4/CdS/CdTe cell demonstrating an NREL-confirmed total-area efficiency of 15.8% (V-oc=844.3 mV, J(sc)=25.00 mA/cm(2), and fill factor=74.82%). This high-performance cell is one of the best thin-film CdTe solar cells in the world. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wu, X (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 14 TC 80 Z9 85 U1 4 U2 38 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2001 VL 89 IS 8 BP 4564 EP 4569 DI 10.1063/1.1351539 PG 6 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500053 ER PT J AU Muralidharan, G Mehta, A Cherian, S Thundat, T AF Muralidharan, G Mehta, A Cherian, S Thundat, T TI Analysis of amplification of thermal vibrations of a microcantilever SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ATOMIC-FORCE MICROSCOPE; CANTILEVERS; NOISE AB We examine the conditions under which the small amplitude of thermal vibrations of cantilevers typically used for atomic force microscopy and sensor applications can be enhanced through a feedback mechanism. Using a simple mathematical model with two independent measurable physical parameters, a time delay tau and a gain factor G, we show that for certain values of these two parameters, such amplification is feasible. Experimental measurements of the two parameters when amplification succeeded show that these fall in the range predicted by the calculations. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Thundat, T (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Muralidharan, Govindarajan/J-6155-2015 NR 14 TC 18 Z9 19 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2001 VL 89 IS 8 BP 4587 EP 4591 DI 10.1063/1.1357779 PG 5 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500056 ER PT J AU Chialvo, AA Simonson, JM Cummings, PT Kusalik, PG AF Chialvo, AA Simonson, JM Cummings, PT Kusalik, PG TI On the determination of orientational configurational temperature from computer simulation SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SCATTERING; LIQUID AB A straightforward derivation for the configurational temperature associated with the orientational Omega (N) portion of the configurational phase space of the molecules in an open system is presented. Explicit relationships are given for determining the configurational temperatures in classical simulations of molecular liquids, such as water, and their forms and their evaluation discussed. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. Univ Tennessee, Div Chem Technol, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Dalhousie Univ, Dept Chem, Halifax, NS B3H 4J3, Canada. RP Chialvo, AA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Cummings, Peter/B-8762-2013; OI Cummings, Peter/0000-0002-9766-2216; Chialvo, Ariel/0000-0002-6091-4563 NR 19 TC 12 Z9 12 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 15 PY 2001 VL 114 IS 15 BP 6514 EP 6517 DI 10.1063/1.1357792 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 418VG UT WOS:000167914400004 ER PT J AU Wright, DL McGraw, R Rosner, DE AF Wright, DL McGraw, R Rosner, DE TI Bivariate extension of the quadrature method of moments for modeling simultaneous coagulation and sintering of particle populations SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE moment methods; coagulation; sintering; aerosol dynamics; combustion aerosols ID SIZE DISTRIBUTION; OPTICAL-PROPERTIES; ATMOSPHERIC AEROSOLS; EQUATION; DYNAMICS; EVOLUTION AB We extendthe application of moment methods to multivariate suspended particle population problems-those for which size alone is insufficient to specify the state of a particle in the population. Specifically, a bivariate extension of the quadrature method of moments (QMOM) (R. McGraw, Aerosol Sci. Technol. 27, 255 (1997)) is presented for efficiently modeling the dynamics of a population of inorganic nanoparticles undergoing simultaneous coagulation and particle sintering. Continuum regime calculations are presented for the Koch-Friedlander-Tandon-Rosner model, which includes coagulation by Brownian diffusion (evaluated for particle fractal dimensions, D-f, in the range 1.8-3) and simultaneous sintering of the resulting aggregates (P. Tandon and D. E. Rosner, J. Colloid Interface Sci. 213, 273 (1999)). For evaluation purposes, and to demonstrate the computational efficiency of the bivariate QMOM, benchmark calculations are carried out using a high-resolution discrete method to evolve the particle distribution function rt(nu, a) for short to intermediate times (where nu and a are particle volume and surface area, respectively). Time evolution of a selected set of 36 low-order mixed moments is obtained by integration of the full bivariate distribution and compared with the corresponding moments obtained directly using two different extensions of the QMOM. With the more extensive treatment, errors of less than 1% are obtained over substantial aerosol evolution, while requiring only a few minutes (rather than days) of CPU time. Longer time QMOM simulations lend support to the earlier finding of a self-preserving limit for the dimensionless joint (nu, a) particle distribution function under simultaneous coagulation and sintering (Tandon and Rosner, 1999; D. E. Rosner and S, Yu, AIChE J., 47 (2001)). We demonstrate that, even in the bivariate case, it is possible to use the QMOM to rapidly model the approach to asymptotic behavior, allowing an immediate assessment of when previously established asymptotic results can be applied to dynamical situations of current/future interest. (C) 2001 Academic Press. C1 Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. Yale Univ, Dept Chem Engn, New Haven, CT 06520 USA. RP McGraw, R (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. NR 33 TC 115 Z9 119 U1 0 U2 10 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD APR 15 PY 2001 VL 236 IS 2 BP 242 EP 251 DI 10.1006/jcis.2000.7409 PG 10 WC Chemistry, Physical SC Chemistry GA 424XB UT WOS:000168258300006 ER PT J AU Patzek, TW Silin, DB AF Patzek, TW Silin, DB TI Shape factor and hydraulic conductance in noncircular capillaries I. One-phase creeping flow SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE noncircular capillary; shape factor; pore network; hydraulic conductance; one-phase flow; conformal mapping ID PORE AB We use the Mason-Morrow shape factor, i.e., a dimensionless hydraulic radius, and corner half-angles to capture the geometry of noncircular capillaries pertinent to a physically adequate pore network description of porous media. We give analytic expressions for random corner half-angles that satisfy a given shape factor calculated from the microscopic images of pore space. We demonstrate that use of the shape factor leads to particularly simple expressions for the hydraulic conductance in single-phase flow through noncircular capillaries. In particular, we obtain the hydraulic conductances of arbitrary triangular ducts semianalytically, using conformal mapping. The conductances of equilateral triangular, rectangular, and elliptic ducts are calculated analytically. (C) 2001 Academic Press. C1 Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lib, Berkeley, CA 94720 USA. RP Patzek, TW (reprint author), Univ Calif Berkeley, Dept Civil & Environm Engn, 591 Evans Hall, Berkeley, CA 94720 USA. NR 20 TC 71 Z9 76 U1 0 U2 12 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD APR 15 PY 2001 VL 236 IS 2 BP 295 EP 304 DI 10.1006/jcis.2000.7413 PG 10 WC Chemistry, Physical SC Chemistry GA 424XB UT WOS:000168258300013 ER PT J AU Dominguez-Rodriguez, A Gutierrez-Mora, F Jimenez-Melendo, M Routbort, JL Chaim, R AF Dominguez-Rodriguez, A Gutierrez-Mora, F Jimenez-Melendo, M Routbort, JL Chaim, R TI Current understanding of superplastic deformation of Y-TZP and its application to joining SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 9th Israel Materials Engineering Conference (IMEC-9) CY DEC 06-07, 1999 CL TECHNION, ISRAEL INST TECHNOL, HAIFA, ISRAEL HO TECHNION, ISRAEL INST TECHNOL DE Y-TZP; grain boundary sliding; superplastic deformation ID YTTRIA-STABILIZED ZIRCONIA; TEMPERATURE MECHANICAL-PROPERTIES; GRAIN-SIZE; TETRAGONAL ZIRCONIA; CERAMIC COMPOSITES; THRESHOLD STRESS; FLOW; POLYCRYSTALS; CREEP; AL AB A review of the high-temperature, steady-state creep of yttria tetragonal zirconia polycrystals (Y-TZP) as a function of grain size, strain rate, stress, and temperature will be presented in this paper. Data have been analyzed using the standard creep equation incorporating a threshold stress. Microstructural observations of deformed samples indicated that deformation was achieved primarily by grain boundary sliding (GBS). This microscopic characteristic was used to join pieces of these materials. When two pieces of ceramics are compressed in the superplastic regime, GBS will produce a junction between the pieces. Several types of strong junctions have been produced, i.e. between pieces of the same material having different grain sizes, and between pieces of different materials. Scanning electron microscopy of the interfaces showed that each interface was cavity- and crack-free. Vickers indentations and high-temperature mechanical tests indicated that the interfaces were as strong as the matrix. This joining technique allows the construction of a complex shape or a functional gradient material. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Sevilla, Dept Fis Mat Condensada, Seville 41080, Spain. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Technion Israel Inst Technol, Dept Mat Engn, IL-32000 Haifa, Israel. RP Dominguez-Rodriguez, A (reprint author), Univ Sevilla, Dept Fis Mat Condensada, Apartado 1065, Seville 41080, Spain. RI Gutierrez-Mora, Felipe/H-4625-2015; OI Gutierrez-Mora, Felipe/0000-0003-3632-7163; Jimenez Melendo, Manuel/0000-0002-8423-5928; Dominguez-Rodriguez, Arturo/0000-0003-1598-5669 NR 34 TC 17 Z9 18 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD APR 15 PY 2001 VL 302 IS 1 BP 154 EP 161 DI 10.1016/S0921-5093(00)01368-X PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 404CP UT WOS:000167080100025 ER PT J AU Dance, GSC Beemiller, P Yang, Y Van Mater, D Mian, IS Smith, HC AF Dance, GSC Beemiller, P Yang, Y Van Mater, D Mian, IS Smith, HC TI Identification of the yeast cytidine deaminase CDD1 as an orphan C -> U RNA editase SO NUCLEIC ACIDS RESEARCH LA English DT Article ID B MESSENGER-RNA; SACCHAROMYCES-CEREVISIAE; CATALYTIC SUBUNIT; ESCHERICHIA-COLI; EDITING ACTIVITY; ADENOSINE-DEAMINASE; MOLECULAR-CLONING; BINDING PROTEIN; APOBEC-1; EXPRESSION AB Yeast co-expressing rat APOBEC-1 and a fragment of human apolipoprotein B (apoB) mRNA assembled functional editosomes and deaminated C6666 to U in a mooring sequence-dependent fashion. The occurrence of APOBEC-1-complementing proteins suggested a naturally occurring mRNA editing mechanism in yeast. Previously, a hidden Markov model identified seven yeast genes encoding proteins possessing putative zinc-dependent deaminase motifs, Here, only CDD1, a cytidine deaminase, is shown to have the capacity to carry out C -->U editing on a reporter mRNA, This is only the second report of a cytidine deaminase that can use mRNA as a substrate. CDD1-dependent editing was growth phase regulated and demonstrated mooring sequence-dependent editing activity. Candidate yeast mRNA substrates were identified based on their homology with the mooring sequence-containing tripartite motif at the editing site of apoB mRNA and their ability to be edited by ectopically expressed APOBEC-1, Naturally occurring yeast mRNAs edited to a significant extent by CDD1 were. however, not detected. We propose that CDD1 be designated an orphan C -->U editase until its native RNA substrate, if any, can be identified and that it be added to the CDAR (cytidine deaminase acting on RNA) family of editing enzymes. C1 Univ Rochester, Environm Hlth Sci Ctr, Dept Biochem & Biophys, Rochester, NY 14642 USA. Univ Rochester, Environm Hlth Sci Ctr, Dept Pathol, Rochester, NY 14642 USA. Univ Rochester, Ctr Canc, Dept Pathol, Rochester, NY 14642 USA. Univ Rochester, Ctr Canc, Dept Biochem & Biophys, Rochester, NY 14642 USA. Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Univ Rochester, Med Ctr, Dept Biochem & Biophys, 601 Elmwood Ave, Rochester, NY 14642 USA. EM harold_smith@urmc.rochester.edu FU NIDDK NIH HHS [DK43738] NR 63 TC 24 Z9 25 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 EI 1362-4962 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD APR 15 PY 2001 VL 29 IS 8 BP 1772 EP 1780 DI 10.1093/nar/29.8.1772 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 424JL UT WOS:000168229100014 PM 11292850 ER PT J AU Arena, DA Bartynski, RA Nayak, RA Weiss, AH Hulbert, SL AF Arena, DA Bartynski, RA Nayak, RA Weiss, AH Hulbert, SL TI Line shape of the Ag M4,5VV Auger spectra measured by Auger-photoelectron coincidence spectroscopy SO PHYSICAL REVIEW B LA English DT Article ID NARROW-BAND METALS; ELECTRON SPECTRA; SILVER; CU AB We present high resolution Ag M5VV and M4VV Auger spectra obtained in coincidence with 3d(5/2) and 3d(3/2) core photoelectrons, respectively. Auger photoelectron coincidence spectroscopy (APECS) was used to separate these overlapping Auger lines and determine the intrinsic line shape of each spectrum. As the on-site Coulomb correlation energy U of Ag is comparable to twice the 4d bandwidth, 2W, (i.e., U/2W similar to1), the coincidence Auger spectra exhibit both atomiclike and bandlike character. We find that whether considered separately or in combination, neither bandlike nor atomiclike line shapes give a satisfactory account of these Auger spectra. Instead, the intrinsic Ag M5VV and M4VV line shapes are well described by the Cini-Sawatzky theory when it is applied separately to each component of the multiplet structure of the 4d(8)5s(2) Auger final state. A fit to the APECS data indicates that the correlation energy the (1)G(4) multiplet is 4.8+/-0.1 eV. Furthermore, our analysis indicates that the missing intensity in the vicinity of the F-3(4) multiplet in the Ag M5VV Auger line, which has been noted in previous studies, results from a shift in the spectral weight of this multiplet component to higher kinetic energy, into the bandlike region of the spectrum. C1 Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08855 USA. Rutgers State Univ, Surface Modificat Lab, Piscataway, NJ 08855 USA. Univ Texas, Dept Phys, Arlington, TX 76019 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Arena, DA (reprint author), Rutgers State Univ, Dept Phys & Astron, POB 849, Piscataway, NJ 08855 USA. RI Weiss, Alex/G-4941-2011 NR 22 TC 18 Z9 18 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 15 AR 155102 DI 10.1103/PhysRevB.63.155102 PG 7 WC Physics, Condensed Matter SC Physics GA 424CW UT WOS:000168215400034 ER PT J AU de la Figuera, J Schmid, AK Bartelt, NC Pohl, K Hwang, RQ AF de la Figuera, J Schmid, AK Bartelt, NC Pohl, K Hwang, RQ TI Determination of buried dislocation structures by scanning tunneling microscopy SO PHYSICAL REVIEW B LA English DT Article ID METAL-METAL INTERFACES; CU FILMS; THIN CU; GROWTH; RELAXATION; RU(0001); RECONSTRUCTION AB Using scanning tunneling microscopy on Cu/Ru(0001) thin films we have located the depth at which the cores of misfit dislocations lie below the film surface. The procedure is based on matching areas with unknown structure to areas with a known stacking sequence in the same film. Our results show that dislocations occur not only at the Cu/Ru interface, but also at various levels within the Cu films. Our analysis method should be applicable to the characterization of dislocation structures in other ultrathin film systems. C1 Sandia Natl Labs, Livermore, CA 94551 USA. Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. RP Pohl, K (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. RI de la Figuera, Juan/E-7046-2010 OI de la Figuera, Juan/0000-0002-7014-4777 NR 18 TC 22 Z9 22 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 16 AR 165431 DI 10.1103/PhysRevB.63.165431 PG 6 WC Physics, Condensed Matter SC Physics GA 426HH UT WOS:000168343400111 ER PT J AU Feng, Y Rhee, JY Wiener, TA Lynch, DW Hubbard, BE Sievers, AJ Schlagel, DL Lograsso, TA Miller, LL AF Feng, Y Rhee, JY Wiener, TA Lynch, DW Hubbard, BE Sievers, AJ Schlagel, DL Lograsso, TA Miller, LL TI Physical properties of Heusler-like Fe2VAl SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; ELECTRICAL-RESISTIVITY; (FE1-XVX)(3)AL ALLOYS; TRANSPORT; CONDUCTION; COMPOUND; BEHAVIOR; FESI AB A comprehensive characterization of the compound Fe2VAl was carried out. Samples grown by are melting or the Bridgman method have Al and Fe deficiencies of up to 5 at. %. Czochralski-grown samples were Fe rich and Al deficient. X-ray diffraction implies appreciable antisite disorder in all of our samples. Fourier-transform infrared (FTIR) spectroscopy measurements showed that the carrier density and scattering time had little sample-to-sample variation or temperature dependence for near-stoichiometric samples. FTIR and de resistivity suggest that the transport properties of Fe2VAl are influenced by both localized and delocalized carriers, with the former primarily responsible for the negative temperature coefficient of resistivity. Magnetization measurements reveal that near-stoichiometric samples have superparamagnetic clusters with at least two sizes of moments. We conclude that in Fe2VAl, antisite disorder causes significant modification to the semimetallic band structure proposed theoretically. With antisite disorder considered, we are now able to explain most of the physical properties of Fe2VAl. None of our data suggest heavy-fermion behavior in our samples. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Cornell Univ, Atom & Solid State Phys Lab, Ithaca, NY 14853 USA. RP Feng, Y (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RI Rhee, Joo/D-2987-2011 NR 31 TC 55 Z9 55 U1 1 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 16 AR 165109 DI 10.1103/PhysRevB.63.165109 PG 12 WC Physics, Condensed Matter SC Physics GA 426HH UT WOS:000168343400028 ER PT J AU Franceschetti, A Zunger, A AF Franceschetti, A Zunger, A TI Exciton dissociation and interdot transport in CdSe quantum-dot molecules SO PHYSICAL REVIEW B LA English DT Article ID SMALL SEMICONDUCTOR CRYSTALLITES; PSEUDOPOTENTIAL CALCULATIONS; ELECTRON; PHOTOCONDUCTIVITY; INAS; INP AB One of the most important parameters that determine the transport properties of a quantum dot array is the exciton dissociation energy, i.e., the energy DeltaE required to dissociate an exciton into an electron and a hole localized in different dots. We show that a pseudopotential calculation for a dot molecule, coupled with a basic configuration interaction calculation of the exciton energy levels, provides directly the exciton dissociation energy, including the effects of wave function overlap, screened Coulomb attraction between the electron and the hole in different dots, and polarization effects. We find that DeltaE decreases as the interdot distance decreases and as the dielectric constant of the medium increases. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Franceschetti, A (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. EM azunger@nrel.gov RI Zunger, Alex/A-6733-2013 NR 9 TC 10 Z9 10 U1 1 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 15 AR 153304 DI 10.1103/PhysRevB.63.153304 PG 4 WC Physics, Condensed Matter SC Physics GA 424CW UT WOS:000168215400010 ER PT J AU Funsten, HO Ritzau, SM Harper, RW AF Funsten, HO Ritzau, SM Harper, RW TI Negative helium ions exiting a carbon foil at keV energies SO PHYSICAL REVIEW B LA English DT Article ID CHARGE-EXCHANGE; HE; SURFACES; NEUTRALIZATION; ATOM; LIFETIME; STATES; RESONANCES; SHIFTS AB He- is observed in the exit charge state distributions of He transmitted through a thin carbon foil over an energy range of 8-80 keV. The observed exit fraction of He- must be formed in the bulk foil or within several Angstroms of the exit surface and reaches a maximum of 2.6 x 10(-4) at 0.7 upsilon (0) where upsilon (0) is the Bohr velocity. The probability of forming the observed He- from its source population of He+ by two sequential electron-capture events decreases exponentially with increasing velocity. This behavior is similar to that of He transiting a Cs vapor, for which this dependence is the result of individual cross sections that collectively drive the charge-state distribution toward higher positive-charge states with increasing projectile velocity. No isotope effect in the exit charge state distributions of He-3 and He-4 is observed within experimental error. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Funsten, HO (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM hfunsten@lanl.gov RI Funsten, Herbert/A-5702-2015 OI Funsten, Herbert/0000-0002-6817-1039 NR 44 TC 3 Z9 3 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 15 AR 155416 DI 10.1103/PhysRevB.63.155416 PG 6 WC Physics, Condensed Matter SC Physics GA 424CW UT WOS:000168215400086 ER PT J AU Ishii, S Ohno, K Kawazoe, Y Louie, SG AF Ishii, S Ohno, K Kawazoe, Y Louie, SG TI Ab initio GW quasiparticle energies of small sodium clusters by an all-electron mixed-basis approach SO PHYSICAL REVIEW B LA English DT Article ID SELF-CONSISTENT CALCULATIONS; QUASI-PARTICLE STATES; SMALL METAL-CLUSTERS; MOLECULAR-DYNAMICS; RESPONSE FUNCTIONS; BAND-GAPS; SEMICONDUCTORS; POTENTIALS; SPECTRA; SOLIDS AB A state-of-the-art GW calculation is carried out for small sodium clusters, Na-2, Na-4, Na-6, and Na-8. The quasiparticle energies are evaluated by employing an nb initio GW code based on an all-electron mixed-basis approach, which uses both plane waves and atomic orbitals as basis functions. The calculated ionization potential and the electron affinity are in excellent agreement with available experimental data. The exchange and correlation parts to the electron self-energy within the GW approximation are presented from the view point of their size dependence. In addition, the effect of the off-diagonal elements of the self-energy corrections to the local-density-approximation exchange-correlation potential is discussed. Na-2 and Na-8 have a larger energy gap than Na-4 and Na-6, consistent with the fact that they are magic number clusters. C1 Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Yokohama Natl Univ, Fac Engn, Dept Phys, Yokohama, Kanagawa 2408501, Japan. RP Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan. RI Kawazoe, Yoshiyuki/C-2998-2011 NR 41 TC 37 Z9 37 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 15 AR 155104 DI 10.1103/PhysRevB.63.155104 PG 6 WC Physics, Condensed Matter SC Physics GA 424CW UT WOS:000168215400036 ER PT J AU Li, JH Kulik, J Holy, V Zhong, Z Moss, SC Zhang, Y Ahrenkiel, SP Mascarenhas, A Bai, JM AF Li, JH Kulik, J Holy, V Zhong, Z Moss, SC Zhang, Y Ahrenkiel, SP Mascarenhas, A Bai, JM TI X-ray diffraction from CuPt-ordered III-V ternary semiconductor alloy films SO PHYSICAL REVIEW B LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; DOMAIN-STRUCTURES; LENGTH MISMATCH; PHASE EPITAXY; LAYERS; GAINP; GROWTH; PHOTOLUMINESCENCE; MECHANISM AB A model has been developed to describe x-ray scattering from CuPt-type ordered III-V ternary semiconductor alloys. The model takes into account the size distribution of the two different laminae-shaped variants, the random distribution of antiphase domain boundaries in each variant, and the atomic displacements due to the bond-length difference between the two constitutive binary materials. A synchrotron x-ray source was employed to measure the weak-ordering reflections from CuPt-ordered Ga0.5In0.5P and Al0.5In0.5As samples. By comparing the experimental results and the model calculations, structure information, including the average number of atomic layers in the laminae of each variant, the average antiphase domain size, and the average order parameter in each variant, were obtained. Results from single-variant films and poorly ordered films are also discussed. C1 Univ Houston, Dept Phys, Houston, TX 77204 USA. Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Masaryk Univ, Fac Sci, Dept Solid State Phys, CS-61137 Brno, Czech Republic. Natl Renewable Energy Lab, Golden, CO 80401 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Li, JH (reprint author), Univ Houston, Dept Phys, Houston, TX 77204 USA. RI Bai, Jianming/O-5005-2015; Holy, Vaclav/E-1508-2017 OI Holy, Vaclav/0000-0002-0370-6928 NR 33 TC 9 Z9 9 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 15 AR 155310 DI 10.1103/PhysRevB.63.155310 PG 11 WC Physics, Condensed Matter SC Physics GA 424CW UT WOS:000168215400062 ER PT J AU Mahan, GD AF Mahan, GD TI Energy bands of the Bethe lattice SO PHYSICAL REVIEW B LA English DT Article ID HUBBARD-MODEL; TRANSITION; DENSITY AB Energy bands are derived for the tight-binding model of particle motion on the Bethe lattice. The energy bands are used to calculate the density of states, which gives the standard answer. The bands are also used to calculate the ground state energy as a function of band filling. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Mahan, GD (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. NR 17 TC 2 Z9 2 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 15 AR 155110 PG 5 WC Physics, Condensed Matter SC Physics GA 424CW UT WOS:000168215400042 ER PT J AU Nakajima, M Harima, H Morita, K Itoh, KM Mizoguchi, K Haller, EE AF Nakajima, M Harima, H Morita, K Itoh, KM Mizoguchi, K Haller, EE TI Coherent confined LO phonons in Ge-70/Ge-74 isotope superlattices generated by ultrafast laser pulses SO PHYSICAL REVIEW B LA English DT Article ID ACOUSTIC PHONONS; CONDENSED MEDIA; OPTICAL PHONONS; GE; GERMANIUM AB Generation of high-order coherent confined LO phonon modes by 20-fs ultrashort laser pulse irradiation was observed in a new class of nonpolar semiconductors; Ge-70/Ge-74 isotope superlattices. The phonon oscillations were Fourier transformed and compared with a theoretical calculation based on a planar force-constant model and a bond polarizability approach. The comparison between the calculated and Fourier transformed spectra shows clearly that the amplitudes of coherent phonons are determined solely by the degree of the atomic displacement and that only the Raman active odd-number-order modes are observable. The spectra taken with variety of polarization of pump beam show clearly that the generation mechanism of coherent phonons in nonpolar semiconductor like Ge is stimulated Raman scattering. C1 Osaka Univ, Dept Appl Phys, Suita, Osaka 5650871, Japan. Keio Univ, Dept Appl Phys & Physicoinformat, Kohoku Ku, Kanagawa 2238522, Japan. JST, PRESTO, Kohoku Ku, Kanagawa 2238522, Japan. Osaka City Univ, Dept Appl Phys, Sumiyoshi Ku, Osaka 5588585, Japan. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Nakajima, M (reprint author), Osaka Univ, Dept Appl Phys, 2-1 Yamadaoka, Suita, Osaka 5650871, Japan. RI Nakajima, Makoto/A-1333-2016; Itoh, Kohei/C-5738-2014 OI Nakajima, Makoto/0000-0002-0351-2197; NR 20 TC 13 Z9 13 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 16 AR 161304 DI 10.1103/PhysRevB.63.161304 PG 4 WC Physics, Condensed Matter SC Physics GA 426HH UT WOS:000168343400009 ER PT J AU Pizzagalli, L Galli, G Klepeis, JE Gygi, F AF Pizzagalli, L Galli, G Klepeis, JE Gygi, F TI Structure and stability of germanium nanoparticles SO PHYSICAL REVIEW B LA English DT Article ID SEMICONDUCTOR NANOCRYSTALS; SI NANOCRYSTALS; ELECTRONIC-PROPERTIES; CDSE NANOCRYSTALS; GE NANOCRYSTALS; NANOCLUSTERS; DEPENDENCE; CHEMISTRY; PHASES AB In order to tailor the properties of nanodots, it is essential to separate the effects of quantum confinement from those due to the surface, and to determine the mechanisms by which preparation conditions can influence the properties of the dot. We address these issues for the case of small Ge clusters (1-2.5 nm), using a combination of empirical and first-principles molecular-dynamics techniques. Our results show that over a wide temperature range, the diamond structure is more stable than tetragonal-like structures for clusters containing more than 40 atoms; however, the magnitude of the energy difference is strongly dependent on the structure and termination of the surface. On the basis of our calculations, we propose a possible mechanism for the formation of metastable tetragonal clusters observed in vapor deposition experiments, by cold quenching of amorphous nanoparticles exhibiting unsaturated, reconstructed surfaces. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Pizzagalli, L (reprint author), Univ Poitiers, Met Phys Lab, F-6960 Futuroscope, France. RI Pizzagalli, Laurent/A-1445-2013 NR 33 TC 52 Z9 53 U1 1 U2 17 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 16 AR 165324 DI 10.1103/PhysRevB.63.165324 PG 5 WC Physics, Condensed Matter SC Physics GA 426HH UT WOS:000168343400074 ER PT J AU Shen, XJ Kwak, H Mocuta, D Radojevic, AM Smadici, S Osgood, RM AF Shen, XJ Kwak, H Mocuta, D Radojevic, AM Smadici, S Osgood, RM TI Observation of a one-dimensional state on stepped Cu(775) SO PHYSICAL REVIEW B LA English DT Article ID 2-PHOTON PHOTOEMISSION; METAL-SURFACE; ELECTRONIC-STRUCTURE; ATOMIC OXYGEN; CU(111); CU(100); RECONSTRUCTIONS; LOCALIZATION; ADSORPTION; STM AB We report on using high-resolution angle-resolved two-photon photoemission to observe a one-dimensional surface state 0.27 eV below the Fermi level on a stepped Cu(111) surface. The state is dispersive along the step direction but localized perpendicular to the step orientation. The origin of the state may be explained by confinement due to the step-edge potential. C1 Columbia Univ, Columbia Radiat Lab, New York, NY 10027 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Osgood, RM (reprint author), Columbia Univ, Columbia Radiat Lab, New York, NY 10027 USA. NR 41 TC 22 Z9 22 U1 2 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 16 AR 165403 DI 10.1103/PhysRevB.63.165403 PG 8 WC Physics, Condensed Matter SC Physics GA 426HH UT WOS:000168343400083 ER PT J AU Shumway, J Franceschetti, A Zunger, A AF Shumway, J Franceschetti, A Zunger, A TI Correlation versus mean-field contributions to excitons, multiexcitons, and charging energies in semiconductor quantum dots SO PHYSICAL REVIEW B LA English DT Article ID MONTE-CARLO; ELECTRONIC-STRUCTURE; OPTICAL-PROPERTIES; MAGNETIC-FIELD; COULOMB ISLAND; HALL REGIME; STATES; BIEXCITONS; SPECTROSCOPY; PHOTOLUMINESCENCE AB Single-dot spectroscopy is now able to resolve the energies of excitons, multiexcitons, and charging of semiconductor quantum dots with less than or similar to 1 meV resolution. We discuss the physical content of these energies and show how they can be calculated via quantum Monte Carlo (QMC) and configuration interaction (CT) methods. The spectroscopic energies have three pieces: (i) a "perturbative part" reflecting carrier-carrier direct and exchange Coulomb energies obtained from fixed single-particle orbitals, (ii) a "self-consistency correction" when the single particle orbitals are allowed to adjust to the presence of carrier-carrier interaction, and (iii) a "correlation correction." We first apply the QMC and CI methods to a model single-particle Hamiltonian: a spherical dot with a finite barrier and single-band effective mass. This allows us to test the convergence of the CI and to establish the relative importance of the three terms (i)-(iii) above. Next, we apply the CI method to a realistic single-particle Hamiltonian for a CdSe dot, including via a pseudopotential description the atomistic features, multiband coupling, spin-orbit effects, and surface passivation. We include all bound states (up to 40 000 Slater determinants) in the CI expansion. Our study shows that (1) typical exciton transition energies, which are similar to 1 eV, can be calculated to better than 95% by perturbation theory, with only a similar to 2 meV correlation correction; (2) typical electron addition energies are similar to 40 meV, of which correlation contributes very little (similar to 1 meV); (3) typical biexciton binding energies are positive and similar to 10 meV and almost entirely due to correlation energy, and exciton addition energies are similar to 30 meV with nearly all contribution due to correlation; (4) while QMC is currently limited to a single-band effective-mass Hamiltonian, CI may be used with much more realistic models, which capture the correct symmetries and electronic structure of the dots, leading to qualitatively different predictions from effective-mass models; and (5) CI gives excited state energies necessary to identify some of the peaks that appear in single-dot photoluminescence spectra. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Shumway, J (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Zunger, Alex/A-6733-2013 NR 64 TC 63 Z9 63 U1 0 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 15 AR 155316 DI 10.1103/PhysRevB.63.155316 PG 13 WC Physics, Condensed Matter SC Physics GA 424CW UT WOS:000168215400068 ER PT J AU Suchorski, Y Beben, J Imbihl, R James, EW Liu, DJ Evans, JW AF Suchorski, Y Beben, J Imbihl, R James, EW Liu, DJ Evans, JW TI Fluctuations and critical phenomena in catalytic CO oxidation on nanoscale Pt facets SO PHYSICAL REVIEW B LA English DT Article ID SURFACE-REACTION MODEL; NOISE-INDUCED BISTABILITY; PHASE-TRANSITIONS; FIELD EMITTER; HETEROGENEOUS CATALYSIS; CRYSTAL PLANES; DIFFUSION; PROPAGATION; COOXIDATION; ADSORPTION AB Local fluctuations and fluctuation-induced transitions in catalytic CO oxidation are studied with field electron microscopy on the (112) facets of a [100]-oriented Pt field emitter tip. The reaction is investigated in the bistable range close to the cusp point (critical point) that terminates the bistability range in p(CO), T-parameter space. The amplitude and the spatial coherence of the fluctuations increase on approaching the critical point. The fluctuations are spatially well correlated on each flat (112) facet, but their correlation decays rapidly across stepped regions that terminate the flat facets. On smaller (112) facets, an onset of fluctuation-induced transitions is observed earlier (i.e., further away from the critical point) than for larger (112) facets. The behavior of the reaction system near the cusp point appears to be similar to that of an equilibrium system near the critical point. The observed fluctuations are mimicked in a simple reaction model for CO oxidation on surfaces that incorporates both rapid diffusion of adsorbed CO, and superlattice ordering of adsorbed immobile oxygen. The steady states of the model exhibit a cusp bifurcation, from a regime of bistability to one of monostability. The fluctuations increase near this cusp point, as in experiment. This behavior is analyzed via kinetic Monte Carlo simulations and analytic procedures, focusing on the consequences for fluctuation-induced transitions. C1 Univ Hannover, Inst Phys Chem & Elektrochem, D-30167 Hannover, Germany. Univ Wroclaw, Inst Phys Expt, PL-50204 Wroclaw, Poland. Iowa State Univ, Ames Lab, Ames, IA 50010 USA. Iowa State Univ, Dept Math, Ames, IA 50017 USA. RP Suchorski, Y (reprint author), Univ Hannover, Inst Phys Chem & Elektrochem, Callinstr 3-3A, D-30167 Hannover, Germany. NR 50 TC 59 Z9 59 U1 1 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 16 AR 165417 DI 10.1103/PhysRevB.63.165417 PG 12 WC Physics, Condensed Matter SC Physics GA 426HH UT WOS:000168343400097 ER PT J AU Zhang, Y Mascarenhas, A Xin, HP Tu, CW AF Zhang, Y Mascarenhas, A Xin, HP Tu, CW TI Scaling of band-gap reduction in heavily nitrogen doped GaAs SO PHYSICAL REVIEW B LA English DT Article ID MODULATION SPECTROSCOPY; GAAS1-XNX ALLOYS; IMPURITY BAND; ELECTROREFLECTANCE; PHOTOLUMINESCENCE; SEMICONDUCTORS; DEPENDENCE; GANXAS1-X AB The band-gap reduction caused by heavy impurity doping in a semiconductor can be written as deltaE(g)(x) proportional tox(alpha), where x is the mole fraction of the impurities, and alpha is the scaling exponent. It is well known that a = 1/3 for n- or p-type (i.e., charged) doping, where the isolated impurity center forms bound states. In contrast, the incorporation of isoelectronic impurities into a semiconductor commonly results in alloy formation. In this case, the impurities do not form any bound states (with small cluster sizes), and one finds that alpha = 1. However, for the case of nitrogen doping in GaAs, although isolated nitrogen impurities do not form bound states, nitrogen impurity pairs do, and we find alpha = 2/3. The scaling rule revealed here demonstrates that the dominant mechanism fur the large band-gap reduction observed in GaAs1-xNx is the formation of an impurity band associated with nitrogen pair bound states. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. RP Zhang, Y (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM yzhang@nrel.gov NR 31 TC 63 Z9 65 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 15 PY 2001 VL 63 IS 16 AR 161303 DI 10.1103/PhysRevB.63.161303 PG 4 WC Physics, Condensed Matter SC Physics GA 426HH UT WOS:000168343400008 ER PT J AU Dalvit, DAR Mazzitelli, FD Molina-Paris, C AF Dalvit, DAR Mazzitelli, FD Molina-Paris, C TI One-loop graviton corrections to Maxwell's equations SO PHYSICAL REVIEW D LA English DT Article ID QUANTUM-GRAVITY; GRAVITATIONAL-FIELD; LIGHT PHOTONS; QED VACUA; FLUCTUATIONS; PROPAGATION; SPACETIMES; FASTER; GEODESICS; VELOCITY AB We compute the graviton induced corrections to Maxwell's equations in the one-loop and weak field approximations. The corrected equations are analogous to the classical equations in anisotropic and inhomogeneous media. We analyze in particular the corrections to the dispersion relations. When the wavelength of the electromagnetic held is much smaller than a typical length scale of the graviton two-point function, the speed of light depends on the direction of propagation and on the polarization of the radiation. In the opposite case, the speed of light may also depend on the energy of the electromagnetic radiation. We study in detail wave propagation in two special backgrounds: flat Robertson-Walker and static, spherically symmetric space-times. In the case of a flat Robertson-Walker gravitational background we find that the corrected electromagnetic held equations correspond to an isotropic medium with a time-dependent effective refractive index. For a static, spherically symmetric background the graviton fluctuations induce a vacuum structure which causes birefringence in the propagation of light. C1 Univ Calif Los Alamos Natl Lab, Theoret Div T 6, Los Alamos, NM 87545 USA. Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Fis JJ Giambiagi, RA-1428 Buenos Aires, DF, Argentina. INTA, CSIC, Ctr Astrobiol, Madrid 28850, Spain. RP Dalvit, DAR (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div T 6, MS B288, Los Alamos, NM 87545 USA. EM dalvit@lanl.gov; fmazzi@df.uba.ar; molina@laeff.esa.es NR 37 TC 20 Z9 20 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 APR 15 PY 2001 VL 63 IS 8 AR 084023 DI 10.1103/PhysRevD.63.084023 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 423XQ UT WOS:000168203400052 ER PT J AU Vo-Dinh, T Cullum, BM Stokes, DL AF Vo-Dinh, T Cullum, BM Stokes, DL TI Nanosensors and biochips: frontiers in biomolecular diagnostics SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article; Proceedings Paper CT 5th European Conference on Optical Chemical Sensors and Biosensors, Europt(r)ode V-Opt(r)ode 2000 CY APR 16-19, 2000 CL LYON, FRANCE DE index; nanosensor; biosensor; nanotechnology; biochip; microchip; benzopyrene tetrol; HIV; cancer ID FT-IR SPECTROMETRY; CAPILLARY ELECTROPHORESIS; GAS-CHROMATOGRAPHY; MASS-SPECTROMETRY; CHEMICAL SENSORS; BIOSENSORS; DNA; SEPARATION AB In the past two decades, the biotechnology and medical fields have seen great advances in the development of novel technologies that open new horizons for identifying and quantifying biomolecules, and diagnosing diseases. This manuscript provides an overview of two of those important technologies, nanosensors and biochips. We describe various types of nanosensors and biochips that have been developed for biological and medical applications, along with significant advances achieved over the last several years in these technologies. Some applications of nanosensors, developed in our laboratory for single-cell analysis, and applications of biochips for biological sensing of pathogenic agents and medical diagnostics are described to illustrate the usefulness and potential of these technologies. (C) 2001 Elsevier Science B.V. Ah rights reserved. C1 Oak Ridge Natl Lab, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. RP Vo-Dinh, T (reprint author), Oak Ridge Natl Lab, Adv Monitoring Dev Grp, Bethel Valley Rd,MS-6101,POB 2008, Oak Ridge, TN 37831 USA. NR 47 TC 142 Z9 147 U1 7 U2 42 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD APR 15 PY 2001 VL 74 IS 1-3 BP 2 EP 11 DI 10.1016/S0925-4005(00)00705-X PG 10 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 424DW UT WOS:000168217700002 ER PT J AU Mallis, MM Neri, DF Oyung, R Colletti, L Nguyen, T Dinges, DF AF Mallis, MM Neri, DF Oyung, R Colletti, L Nguyen, T Dinges, DF TI Factors associated with behavioral alertness in pilots flying simulated night flights SO SLEEP LA English DT Meeting Abstract C1 NASA, Ames Res Ctr, Ames, IA 50011 USA. San Jose State Univ, San Jose, CA 95192 USA. Univ Penn, Philadelphia, PA 19104 USA. NR 1 TC 2 Z9 2 U1 0 U2 0 PU AMER ACAD SLEEP MEDICINE PI ROCHESTER PA 6301 BANDEL RD, STE 101, ROCHESTER, MN 55901 USA SN 0161-8105 J9 SLEEP JI Sleep PD APR 15 PY 2001 VL 24 SU S MA 202 BP A123 EP A124 PG 2 WC Clinical Neurology; Neurosciences SC Neurosciences & Neurology GA 424KF UT WOS:000168230900204 ER PT J AU Campbell, L Brunger, MJ Nolan, AM Kelly, LJ Wedding, AB Harrison, J Teubner, PJO Cartwright, DC McLaughlin, B AF Campbell, L Brunger, MJ Nolan, AM Kelly, LJ Wedding, AB Harrison, J Teubner, PJO Cartwright, DC McLaughlin, B TI Integral cross sections for electron impact excitation of electronic states of N-2 SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID NITROGEN MOLECULE; TRANSPORT; N2; E3-SIGMA-G+; THRESHOLD; SWARMS; GASES AB We report integral cross sections (ICSs) for electron impact excitation of the A (3)Sigma (+)(u), B (3)Pi (g),: W (3)Delta (u), B' (3)Sigma (-)(u), a' (1)Sigma (-)(u), a (1)Pi (g), omega (1)Delta (u), C (3)Pi (u), E (3)Sigma (+)(g) and a" (1)Sigma (+)(g) electronic states of Np. The present data, for each state, were derived at five incident electron energies in the range 15-50 eV, from the earlier crossed-beam differential cross section (DCS) measurements of our group. This was facilitated by using a molecular phase shift analysis technique to extrapolate the measured DCSs to 0 degrees and 180 degrees, before pet-forming the integration. A comprehensive comparison of the present ICSs with the results of earlier experimental studies, both crossed beam and electron swarm, and theoretical calculations is provided. This comparison clearly indicates that some of the previous estimates for these excited electronic-state cross sections need to be reassessed. In addition, we have used the present ICSs in a Monte Carlo simulation for modelling the behaviour of an electron swarm in the bulk of a low current N-2 discharge. The macroscopic transport parameters determined from this simulation are compared against those measured from independent swarm-based experiments and the self-consistency of our ICSs evaluated. C1 Flinders Univ S Australia, Sch Chem Phys & Earth Sci, Adelaide, SA 5001, Australia. Def Sci & Technol Org, Maritime Operat Div, Salisbury, SA 5108, Australia. Univ S Australia, Sch Elect & Informat Engn, Mawson Lakes, SA 5095, Australia. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland. RP Campbell, L (reprint author), Flinders Univ S Australia, Sch Chem Phys & Earth Sci, GPO Box 2100, Adelaide, SA 5001, Australia. RI Wedding, Bruce/F-4166-2013 OI Wedding, Bruce/0000-0002-5185-5100 NR 37 TC 73 Z9 73 U1 0 U2 10 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 APR 14 PY 2001 VL 34 IS 7 BP 1185 EP 1199 DI 10.1088/0953-4075/34/7/303 PG 15 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 428JE UT WOS:000168457900008 ER PT J AU Padyana, AK Bhat, VB Madyastha, KM Rajashankar, KR Ramakumar, S AF Padyana, AK Bhat, VB Madyastha, KM Rajashankar, KR Ramakumar, S TI Crystal structure of a light-harvesting protein C-phycocyanin from Spirulina platensis SO BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS LA English DT Article DE crystal structure; C-phycocyanin; light-harvesting; phycobiliprotein; bilin; chromophore; Spirulina platensis ID CYANOBACTERIUM MASTIGOCLADUS-LAMINOSUS; ANGSTROM RESOLUTION; ENERGY-TRANSFER; 2.2 ANGSTROM; REFINEMENT; CRYSTALLIZATION; ALLOPHYCOCYANIN; PHYCOBILISOME; CRYSTALLOGRAPHY; PHYCOERYTHRIN AB The crystal structure of C-phycocyanin, a light-harvesting phycobiliprotein from cyanobacteria (blue-green algae) Spirulina platensis has been solved by molecular replacement technique. The crystals belong to space group P2(1) with cell parameters a 107.20, b = 115.40, c = 183.04 Angstrom; beta = 90.2 degrees. The structure has been refined to a crystallographic R factor of 19.2% (R-free = 23.9%) using the X-ray diffraction data extending up to 2.2 Angstrom resolution. The asymmetric unit of the crystal cell consists of two (alpha beta)(6)-hexamers, each hexamer being the functional unit in the native antenna rod of cyanobacteria. The molecular structure resembles that of other reported C-phycocyanins. However, the unique form of aggregation of two (alpha beta)(6)-hexamers in the crystal asymmetric unit, suggests additional pathways of energy transfer in lateral direction between the adjacent hexamers involving beta 155 phycocyanobilin chromophores. (C) 2001 Academic Press. C1 Indian Inst Sci, Dept Phys, Bangalore 560012, Karnataka, India. Indian Inst Sci, Dept Organ Chem, Bangalore 560012, Karnataka, India. Indian Inst Sci, Bioinformat Ctr, Bangalore 560012, Karnataka, India. JNCASR, Chem Biol Unit, Bangalore 560064, Karnataka, India. Rockefeller Univ, Upton, NY 11973 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ramakumar, S (reprint author), Indian Inst Sci, Dept Phys, Bangalore 560012, Karnataka, India. NR 37 TC 41 Z9 49 U1 3 U2 21 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0006-291X J9 BIOCHEM BIOPH RES CO JI Biochem. Biophys. Res. Commun. PD APR 13 PY 2001 VL 282 IS 4 BP 893 EP 898 DI 10.1006/bbrc.4663 PG 6 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 424XC UT WOS:000168258400007 PM 11352634 ER PT J AU Romberg, L Simon, M Erickson, HP AF Romberg, L Simon, M Erickson, HP TI Polymerization of FtsZ, a bacterial homolog of tubulin - Is assembly cooperative? SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID DIVISION PROTEIN FTSZ; CELL-DIVISION; ESCHERICHIA-COLI; GTP HYDROLYSIS; DYNAMIC INSTABILITY; INDIVIDUAL MICROTUBULES; SELF-ASSOCIATION; BINDING-PROTEIN; ACTIN FILAMENT; RATE CONSTANTS AB FtsZ is a bacterial homolog of tubulin that is essential for prokaryotic cytokinesis. In vitro, GTP induces FtsZ to assemble into straight, 6-nm-wide polymers. Here we show that the polymerization of these FtsZ filaments most closely resembles noncooperative (or "isodesmic") assembly; the polymers are single-stranded and assemble with no evidence of a nucleation phase and without a critical concentration. We have developed a model for the isodesmic polymerization that includes GTP hydrolysis in the scheme. The model can account for the lengths of the FtsZ polymers and their maximum steady state nucleotide hydrolysis rates. It predicts that unlike microtubules, FtsZ protofilaments consist of GTP bound FtsZ subunits that hydrolyze their nucleotide only slowly and are connected by high affinity longitudinal bonds with a nanomolar K-D. C1 Duke Univ, Med Ctr, Dept Cell Biol, Durham, NC 27710 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Romberg, L (reprint author), Harvard Univ, Sch Med, Inst Chem & Cellular Biol, SGM 604, Boston, MA 02115 USA. FU NIGMS NIH HHS [GM28553] NR 67 TC 139 Z9 140 U1 1 U2 9 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD APR 13 PY 2001 VL 276 IS 15 BP 11743 EP 11753 DI 10.1074/jbc.M009033200 PG 11 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 421UK UT WOS:000168081800044 PM 11152458 ER PT J AU Bischof, O Galande, S Farzaneh, F Kohwi-Shigematsu, T Campisi, J AF Bischof, O Galande, S Farzaneh, F Kohwi-Shigematsu, T Campisi, J TI Selective cleavage of BLM, the Bloom syndrome protein, during apoptotic cell death SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID SYNDROME GENE-PRODUCT; DNA HELICASE ACTIVITY; ESCHERICHIA-COLI; POLY(ADP-RIBOSE) POLYMERASE; PROTEOLYTIC CLEAVAGE; NUCLEAR MATRIX; CASPASES; COMPLEX; RECQ; CLONING AB Bloom syndrome (BS) is an autosomal recessive disorder characterized by a high incidence of cancer and genomic instability. BLM, the protein defective in BS, is a RECQ-like helicase that is presumed to function in mammalian DNA replication, recombination, or repair. We show here that BLM, but not the related RECQ-like helicase WRN, is rapidly cleaved in cells undergoing apoptosis. BLM was cleaved to 47- and 110-kDa major fragments, with kinetics similar to the apoptotic cleavage of poly(A)DP-ribose polymerase. BLM cleavage was prevented by a caspase 3 inhibitor and did not occur in caspase 3-deficient cells. Moreover, recombinant BLM was cleaved to 47- and 110-kDa fragments by caspase 3, but not caspase 6, in vitro. The caspase 3 recognition sequence (TEVD415)-T-412 was verified by mutating aspartate 415 to glycine and showing that this mutation rendered BLM resistant to caspase 3 cleavage. Cleavage did not abolish the BM helicase activity but abolished BLM nuclear foci and the association of BLM with condensed DNA and the insoluble matrix. The results suggest that BLM, but not WRN, is an early selected target during the execution of apoptosis. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Kings Coll London, Guys Kings & St Thomas Sch Med, Rayne Inst, Dept Mol Med, London SE5 9NU, England. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Bldg 84,Rm 144,1 Cyclotron Rd, Berkeley, CA 94720 USA. EM jcampisi@lbl.gov RI Farzaneh, Farzin/B-4902-2009 OI Farzaneh, Farzin/0000-0002-9275-2415 FU NIA NIH HHS [AG11658]; NIGMS NIH HHS [GM59901] NR 69 TC 22 Z9 22 U1 0 U2 1 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD APR 13 PY 2001 VL 276 IS 15 BP 12068 EP 12075 DI 10.1074/jbc.M006462200 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 421UK UT WOS:000168081800086 PM 11154689 ER PT J AU Felinger, A Kele, M Guiochon, G AF Felinger, A Kele, M Guiochon, G TI Identification of the factors that influence the reproducibility of chromatographic retention data SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 24th International Symposium on High Performance Liquid Phase Separations and Related Techniques (HPLC 2000) CY JUN 24-30, 2000 CL SEATTLE, WASHINGTON DE reproducibility; retention data; principal component analysis; stationary phases; LC ID PRINCIPAL COMPONENTS-ANALYSIS; BAND PROFILES; CHEMOMETRIC METHODS; STATIONARY PHASES; C-18 COLUMNS; REPEATABILITY; CLASSIFICATION AB Principal component analysis was used to identify the parameters that influence the column-to-column and batch-to-batch reproducibility of retention times and retention factors measured on Symmetry C-18, Kromasil C-18, Luna C-18 (2) and Vydac RPC18, all reversed-phase silica columns. We devised a procedure that allows the determination of the differences in column volume and packing density between two columns, provided that these columns are packed with identical stationary phases (i.e., phases that originate from the same batch). Principal component analysis of the retention times confirmed that the column-to-column variations of the column volume and the total porosity of the bed are the factors that influence the reproducibility of the retention times, the column volume being the major factor. For the fluctuations of the retention factors, the column phase ratios (nr the bed porosities) and some specific, secondary retention mechanisms are responsible. All the C-18 columns investigated proved to behave in a very similar fashion. Two principal components were always sufficient to characterize the variations of either the: retention times or the retention factors. (C) 2001 Elsevier Science B.V.,All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Veszprem, Dept Analyt Chem, H-8200 Veszprem, Hungary. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, 552 Buehler Hall, Knoxville, TN 37996 USA. RI Felinger, Attila/A-1595-2008 OI Felinger, Attila/0000-0001-7130-1968 NR 18 TC 28 Z9 29 U1 0 U2 4 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 APR 13 PY 2001 VL 913 IS 1-2 BP 23 EP 48 DI 10.1016/S0021-9673(00)01044-X PG 26 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 423BT UT WOS:000168156100004 PM 11355817 ER PT J AU Kele, M Guiochon, G AF Kele, M Guiochon, G TI Repeatability and reproducibility of retention data and band profiles on reversed-phase liquid chromatography columns V. Results obtained with Vydac 218TP C-18 columns SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 24th International Symposium on High Performance Liquid Phase Separations and Related Techniques (HPLC 2000) CY JUN 24-30, 2000 CL SEATTLE, WASHINGTON DE retention data; band profiles; stationary phases; LC; Vydac 218TP C-18 columns ID STATIONARY PHASES; BIOPOLYMER SEPARATIONS; PACKING MATERIALS; SILICA-GEL; MONOLAYERS AB The general goal of this work is to investigate the precision of chromatographic data and to determine which properties of chromatographic columns influence this factor. Chromatographic data were acquired under five different sets of experimental conditions for 30 neutral, acidic and basic test compounds on columns packed with Vydac 218TP C-18, a polymeric, wide-pore silica-based stationary phase. Five columns packed with samples from the same batch of this packing material were used to measure the column-to-column reproducibility and six columns packed with material from six different batches to measure the batch-to-batch reproducibility. The parameters studied were the retention time, the retention and separation factors, the hydrophobic and the steric selectivities, the column efficiency, and the tailing factor. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, 552 Buehler Hall, Knoxville, TN 37996 USA. NR 31 TC 30 Z9 30 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD APR 13 PY 2001 VL 913 IS 1-2 BP 89 EP 112 DI 10.1016/S0021-9673(00)01042-6 PG 24 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 423BT UT WOS:000168156100008 PM 11355847 ER PT J AU Felinger, A Guiochon, G AF Felinger, A Guiochon, G TI Validation of a chromatography data analysis software SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 24th International Symposium on High Performance Liquid Phase Separations and Related Techniques (HPLC 2000) CY JUN 24-30, 2000 CL SEATTLE, WASHINGTON DE validation; data analysis software ID LIQUID-CHROMATOGRAPHY; RETENTION DATA; BAND PROFILES; C-18 COLUMNS; REPRODUCIBILITY; REPEATABILITY; PRECISION; NOISE AB The performance of chromatography data analysis software packages is of cardinal importance when the precision and the accuracy of a chromatographic system are evaluated. Users cannot rely on a procedure generating chromatographic data of known accuracy. Holistic approaches cannot always be entirely trusted. We propose a new method consisting in validating a data analysis package against computer generated chromatograms of exactly known characteristics by feeding these chromatograms into the vendor supplied software and comparing the results supplied by the software and the exact answers. We simulated symmetrical and tailing chromatograms and processed these signals with the Agilent Technologies (formerly Hewlett-Packard) ChemStation software. The noise profile (i.e. the power spectrum of the baseline) was determined for a HPLC UV detector Frier to the calculations, and chromatograms of different signal-to-noise ratios were used for the analysis. For every chromatogram, we simulated 25 replicates with identical signal-to-noise ratios but different noise sequences. In this manner, both the random and the systematic errors of the retention data and peak shape characteristics can be evaluated. When analyzing tailing peaks, we simulated the effects of extra-column band broadening and those of column overload. Our calculations show that the general performance of the data analysis system studied is excellent. The contribution of the random error originating from the data analysis procedure is in most cases negligible compared to the repeatability of the chromatographic measurement itself. (C) 2001 Elsevier Science BN. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Veszprem, Dept Analyt Chem, H-8200 Veszprem, Hungary. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Felinger, Attila/A-1595-2008; Kipke, Daryl/A-2167-2009 OI Felinger, Attila/0000-0001-7130-1968; NR 18 TC 15 Z9 17 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 APR 13 PY 2001 VL 913 IS 1-2 BP 221 EP 231 DI 10.1016/S0021-9673(00)00979-1 PG 11 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 423BT UT WOS:000168156100021 PM 11355816 ER PT J AU Landgraf, R Xenarios, I Eisenberg, D AF Landgraf, R Xenarios, I Eisenberg, D TI Three-dimensional cluster analysis identifies interfaces and functional residue clusters in proteins SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE bioinformatics; evolutionary tracing; protein families; residue patches; phylogeny ID GLYCOLYTIC ENZYME BINDING; HUMAN MUSCLE ALDOLASE; MAP KINASES; CRYSTAL-STRUCTURE; SKELETAL-MUSCLE; SIGNAL-TRANSDUCTION; FRUCTOSE-1,6-BISPHOSPHATE; PHOSPHORYLATION; SPECIFICITY; ACTIVATION AB Three-dimensional cluster analysis offers a method for the prediction of functional residue clusters in proteins. This method requires a representative structure and a multiple sequence alignment as input data. Individual residues are represented in terms of regional alignments that reflect both their structural environment and their evolutionary variation, as defined by the alignment of homologous sequences. From the overall (global) and the residue-specific (regional) alignments, we calculate the global and regional similarity matrices, containing scores for all pairwise sequence comparisons in the respective alignments. Comparing the matrices yields two scores for each residue. The regional conservation score (C-R(x)) defines the conservation of each residue x and its neighbors in 3D space relative to the protein as a whole. The similarity deviation score (S(x)) detects residue clusters with sequence similarities that deviate from the similarities suggested by the full-length sequences. We evaluated 3D cluster analysis on a set of 35 families of proteins with available cocrystal structures, showing small ligand interfaces, nucleic acid interfaces and two types of protein-protein interfaces (transient and stable). We present two examples in detail: fructose-1,6-bisphosphate aldolase and the mitogen-activated protein kinase ERK2. We found that the regional conservation score (C-R(x)) identifies functional residue clusters better than a scoring scheme that does not take 3D information into account. C-R(x) is particularly useful for the prediction of poorly conserved, transient protein-protein interfaces. Many of the proteins studied contained residue clusters with elevated similarity deviation scores. These residue clusters correlate with specificity-conferring regions: 3D cluster analysis therefore represents an easily applied method for the prediction of functionally relevant spatial clusters of residues in proteins. (C) 2001 Academic Press. C1 Univ Calif Los Angeles, US DOE, Lab Struct Biol & Mol Med, Los Angeles, CA 90095 USA. RP Eisenberg, D (reprint author), Univ Calif Los Angeles, US DOE, Lab Struct Biol & Mol Med, 405 Hilgard Ave,Box 951570, Los Angeles, CA 90095 USA. OI Xenarios, Ioannis/0000-0002-3413-6841 FU NIGMS NIH HHS [GM31299] NR 49 TC 177 Z9 182 U1 0 U2 7 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD APR 13 PY 2001 VL 307 IS 5 BP 1487 EP 1502 DI 10.1006/jmbi.2001.4540 PG 16 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 427BY UT WOS:000168386000024 PM 11292355 ER PT J AU Chen, LX Jager, WJH Jennings, G Gosztola, DJ Munkholm, A Hessler, JP AF Chen, LX Jager, WJH Jennings, G Gosztola, DJ Munkholm, A Hessler, JP TI Capturing a photoexcited molecular structure through time-domain X-ray absorption fine structure SO SCIENCE LA English DT Article ID NICKEL(II) TETRAPHENYLPORPHYRIN; SYNCHROTRON-RADIATION; EXCITED-STATE; ELECTRON-TRANSFER; LASER PHOTOLYSIS; CONDENSED-PHASE; SPECTROSCOPY; COMPLEXES; DIFFRACTION; PUMP AB The determination of the structure of transient molecules, such as photoexcited states, in disordered media (such as in solution) usually requires methods with high temporal resolution. The transient molecular structure of a reaction intermediate produced by photoexcitation of NiTPP-L-2 (NiTPP, nickeltetraphenylporphyrin; L, piperidine) in solution was determined by x-ray absorption fine structure (XAFS) data obtained on a 14-nanosecond time scale from a third-generation synchrotron source. The XAFS measurements confirm that photoexcitation Leads to the rapid removal of both axial Ligands to produce a transient square-planar intermediate, NiTPP, with a lifetime of 28 nanoseconds. The transient structure of the photodissociated intermediate is nearly identical to that of the ground state NiTPP, suggesting that the intermediate adopts the same structure as the ground state in a noncoordinating solvent before it recombines with two Ligands to form the more stable octahedrally coordinated NiTPP-L-2. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RP Chen, LX (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Gosztola, David/D-9320-2011 OI Gosztola, David/0000-0003-2674-1379 NR 32 TC 197 Z9 198 U1 2 U2 33 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 APR 13 PY 2001 VL 292 IS 5515 BP 262 EP 264 DI 10.1126/science.1057063 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 421QA UT WOS:000168074000039 PM 11303096 ER PT J AU Barlow, SE Taylor, AE Swanson, K AF Barlow, SE Taylor, AE Swanson, K TI Determination of analytic potentials from finite element computations SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electrostatics; ion optics; ion trap ID HYPERBOLIC ELECTRODES; PENNING TRAPS; ION CLOUD; PAUL TRAP; SIMULATION; RESONANCES AB We present here a general approach for determining analytic electrical potentials from the results of finite difference calculations. Such an approach allows us to explore effects of realistic electrode structures that are not directly amenable to analytic treatment. We then use this technique to find the effects of various modifications of hyperbolic electrode structures of some practical interest by way of example. (C) 2001 Elsevier Science B.V. C1 Pacific NW Natl Lab, WR Wiley Environm Mol Sci, Richland, WA 99352 USA. RP Barlow, SE (reprint author), Pacific NW Natl Lab, WR Wiley Environm Mol Sci, POB 999,K8-88, Richland, WA 99352 USA. NR 32 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD APR 12 PY 2001 VL 207 IS 1-2 BP 19 EP 29 DI 10.1016/S1387-3806(00)00452-8 PG 11 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 431EQ UT WOS:000168619200003 ER PT J AU Canfield, PC Fisher, IR AF Canfield, PC Fisher, IR TI R9Mg34Zn57 icosahedral quasicrystals: The tuning of a model spin glass SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT 13th InTernational Conference on Solid Compounds of Transition Elements CY APR 04-07, 2000 CL STRESA, ITALY DE spin glass; quasicrystal; freezing temperature; magnetization; single crystal ID R = Y; QUASI-CRYSTALS; TERNARY MELT; MAGNETIC-PROPERTIES; LA-ND; GROWTH; TRANSPORT; SM; ER; HO AB The growth of large single grains of face-centered icosahedral R9Mg34Zn57 (R=Y Gd-Er) quasicrystals (referred to as RMgZn from here on) has allowed the detailed study of the intrinsic properties of single phase samples that contain a quasiperiodic rare earth sublattice. By comparison of GdMgZn (Heisenberg moment) to TbMgZn or DyMgZn (non-Heisenberg moments) a clearly reduced freezing temperature (T-f) for GdMgZn can be observed. In order to explore this further pseudo-ternary series such as (Y1-xGdx)MgZn, (Tb1-xGdx)MgZn, (Dy1-xGdx)MgZn, and (Dy1-xTbx)MgZn were grown. Whereas T-f changes monotonically with x for the Gd/Y and Tb/Dy series, there is a rapid rise in T-f for the addition of small amounts of the non-Heisenberg moments Tb or Dy into GdMgZn. For approximately 30% non-Heisenberg substitution on the Gd site T-f passes through a local maximum and is reduced in a roughly linear manner for further increases in the concentration of non-Heisenberg moments. Analysis of these data lead to the conclusion that there is a threshold concentration of non-Heisenberg moments needed to force the whole system to act in a non-Heisenberg manner. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Canfield, PC (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 11 TC 4 Z9 4 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD APR 12 PY 2001 VL 317 BP 443 EP 447 DI 10.1016/S0925-8388(00)01366-9 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 423CE UT WOS:000168157200085 ER PT J AU Mezyk, SP Cooper, WJ Bartels, DM O'Shea, KE Wu, TX AF Mezyk, SP Cooper, WJ Bartels, DM O'Shea, KE Wu, TX TI Radiation chemistry of alternative fuel oxygenates: Substituted ethers SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID GAS-PHASE REACTIONS; TERT-BUTYL ETHER; HYDROXYL RADICALS; AQUEOUS-SOLUTION; RATE CONSTANTS; ELECTRON RADIOLYSIS; HYDRATED ELECTRONS; WATER RADIOLYSIS; ATOMIC-HYDROGEN; REEVALUATION AB Absolute rate constants for the reaction of ethyl tert-butyl, diisopropyl, and methyl tert-amyl ethers with the hydroxyl radical, hydrated electron, and hydrogen atom in water have been determined using electron pulse radiolysis (e(aq)(-) and . OH), absorption spectroscopy (e(aq)(-) and . OH), and EPR free induction decay attenuation (H) measurements. At room temperature the hydroxyl radical reaction was found to be the primary loss pathway, with fate constants of (1.81 +/- 0.09) x 10(9), (2.49 +/- 0.12) x 10(9), and (2.37 +/- 0.12) x 10(9) dm(3) mol(-1) s(-1) determined for these ethers, respectively. The reaction of the hydrated electron with these compounds was not significant, with upper limit values of less than or equal to 10(7), less than or equal to6.7 x 10(6), and less than or equal to4.0 x 10(6) dm(3) mol(-1) s(-1) determined. The corresponding rate constants for hydrogen atom reaction with these ethers were (7.04 +/- 0.11) x 10(6), (6.70 +/- 0.09) x 10(7), and (3.09 +/- 0.09) x 10(6) dm(3) mol(-1) s(-1). On the basis of these rate constant values, the kinetic computer modeling of the free-radical removal of these ethers from NaO-saturated aqueous solution was found to be in very good agreement with experimental steady-state, Co-60, irradiation measurements. C1 Univ N Carolina, Dept Chem, Wilmington, NC 28403 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Florida Int Univ, Dept Chem, Miami, FL 33199 USA. RP Mezyk, SP (reprint author), Univ N Carolina, Dept Chem, 601 S Coll Rd, Wilmington, NC 28403 USA. NR 40 TC 11 Z9 12 U1 1 U2 4 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 APR 12 PY 2001 VL 105 IS 14 BP 3521 EP 3526 DI 10.1021/jp003892y PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 423LN UT WOS:000168177900013 ER PT J AU Cook, AR Dimitrijevic, N Dreyfus, BW Meisel, D Curtiss, LA Camaioni, DM AF Cook, AR Dimitrijevic, N Dreyfus, BW Meisel, D Curtiss, LA Camaioni, DM TI Reducing radicals in nitrate solutions. The NO32- system revisited SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID AQUEOUS-SOLUTION; PULSE-RADIOLYSIS; NITROGEN-DIOXIDE; ELECTRON; NITRITE; GAUSSIAN-2; ENERGIES; ACID AB The one-electron reduction product of nitrate, the NO32- radical, was reinvestigated because of the contemporary interest in its reactivity in high-level liquid radioactive systems, Indirect observations suggest that the same dianion is produced by the precursor to the solvated electron. The redox potential of the couple NO3-/NO32- was calculated, using several ab initio approaches combined with semiempirical solvation models, to be E-o approximate to --1.1 V vs NHE. Using the theoretical prediction to guide the experiment, we find a value of E-o = -0.89 V at zero ionic strength. Kinetic and free-energy-relationship arguments are used to question the acid-base equilibria and reaction mode that converts the NO32- to the oxidizing NO2 radical. It is proposed that the reaction of the dianion with various general acids is an O2- (i.e., water or OH-) transfer to the acid and not proton transfer to NO32-, Implications of the highly negative redox potential of the dianion and the existence of the protonated forms to practical systems are discussed. C1 Univ Notre Dame, Radiat Lab, Notre Dame, IN 46556 USA. Univ Notre Dame, Dept Chem & Biochem, Notre Dame, IN 46556 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Meisel, D (reprint author), Univ Notre Dame, Radiat Lab, Notre Dame, IN 46556 USA. OI Cook, Andrew/0000-0001-6633-3447 NR 40 TC 33 Z9 33 U1 2 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 APR 12 PY 2001 VL 105 IS 14 BP 3658 EP 3666 DI 10.1021/jp0038052 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 423LN UT WOS:000168177900031 ER PT J AU Wang, JX Marinkovic, NS Zajonz, H Ocko, BM Adzic, RR AF Wang, JX Marinkovic, NS Zajonz, H Ocko, BM Adzic, RR TI In situ X-ray reflectivity and voltammetry study of Ru(0001) surface oxidation in electrolyte solutions SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID OXYGEN REDUCTION; CARBON-MONOXIDE; SULFURIC-ACID; RUTHENIUM; SPECTROSCOPY; ADSORPTION; PHASE; ELECTROOXIDATION; STABILITY; INTERFACE AB The electrochemical surface oxidation of Ru(0001) in acid solutions is limited to a one-electron process resulting in one monolayer oxygen uptake at potentials below the onset of bulk oxidation at 1.35 V. In 1 M H2SO4, about (1)/(3) monolayer of bisulfate anions are coadsorbed with hydronium cations at low potentials. The spacing between the top two Ru layers is 2.13 Angstrom at 0.1 V and 2.20 Angstrom at 1.0 V, similar to those found in the gas phase for bare Ru (2.10 Angstrom) and for one monolayer of oxygen on Ru (2.22 Angstrom), respectively. In contrast to Pt(lll) and Au(lll) surfaces, no place exchange is involved in the Ru(0001) surface oxidation. On the oxidized surface, the oxygen species stays on top of a smooth ruthenium surface causing a partial desorption of the bisulfate ions. The lack of subsurface oxygen on a Ru(0001) electrode is postulated to be the origin of its inactivity for CO oxidation found in a separate study. C1 Brookhaven Natl Lab, Energy Sci & Technol Dept, Div Mat & Chem Sci, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Adzic, RR (reprint author), Brookhaven Natl Lab, Energy Sci & Technol Dept, Div Mat & Chem Sci, Bldg 555, Upton, NY 11973 USA. RI Wang, Jia/B-6346-2011; Marinkovic, Nebojsa/A-1137-2016 OI Marinkovic, Nebojsa/0000-0003-3579-3453 NR 40 TC 61 Z9 61 U1 3 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 12 PY 2001 VL 105 IS 14 BP 2809 EP 2814 DI 10.1021/jp0041757 PG 6 WC Chemistry, Physical SC Chemistry GA 423LQ UT WOS:000168178100021 ER PT J AU Albers, RC AF Albers, RC TI An expanding view of plutonium SO NATURE LA English DT Editorial Material C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Condensed Matter Theory Grp, Los Alamos, NM 87545 USA. RP Albers, RC (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Condensed Matter Theory Grp, Los Alamos, NM 87545 USA. NR 3 TC 63 Z9 63 U1 3 U2 6 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 12 PY 2001 VL 410 IS 6830 BP 759 EP 761 DI 10.1038/35071205 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 420TT UT WOS:000168021900034 PM 11298425 ER PT J AU Reich, PB Knops, J Tilman, D Craine, J Ellsworth, D Tjoelker, M Lee, T Wedin, D Naeem, S Bahauddin, D Hendrey, G Jose, S Wrage, K Goth, J Bengston, W AF Reich, PB Knops, J Tilman, D Craine, J Ellsworth, D Tjoelker, M Lee, T Wedin, D Naeem, S Bahauddin, D Hendrey, G Jose, S Wrage, K Goth, J Bengston, W TI Plant diversity enhances ecosystem responses to elevated CO2 and nitrogen deposition SO NATURE LA English DT Article ID CARBON-DIOXIDE ENRICHMENT; ATMOSPHERIC CO2; LONG-TERM; CALCAREOUS GRASSLAND; SPECIES COMPOSITION; BIOMASS; MONOCULTURES; PRODUCTIVITY; BIODIVERSITY; COMPETITION AB Human actions are causing declines in plant biodiversity, increases in atmospheric CO2 concentrations and increases in nitrogen deposition; however, the interactive effects of these factors on ecosystem processes are unknown(1,2). Reduced biodiversity has raised numerous concerns, including the possibility that ecosystem functioning may be affected negatively(1-4), which might be particularly important in the face of other global changes(5,6). Here we present results of a grassland field experiment in Minnesota, USA, that tests the hypothesis that plant diversity and composition influence the enhancement of biomass and carbon acquisition in ecosystems subjected to elevated atmospheric CO2 concentrations and nitrogen deposition. The study experimentally controlled plant diversity (1, 4, 9 or 16 species), soil nitrogen (unamended versus deposition of 4 g of nitrogen per m(2) per yr) and atmospheric CO2 concentrations using free-air CO2 enrichment (ambient, 368 mu mol mol(-1), versus elevated, 560 mu mol mol(-1)). We found that the enhanced biomass accumulation in response to elevated levels of CO2 or nitrogen, or their combination, is less in species-poor than in species-rich assemblages. C1 Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. Univ Minnesota, Dept Ecol Evolut & Behav, St Paul, MN 55108 USA. Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA. Brookhaven Natl Lab, Div Environm Biol, Upton, NY 11973 USA. Univ Nebraska, Sch Nat Resource Sci, Lincoln, NE 68583 USA. RP Reich, PB (reprint author), Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. RI Craine, Joseph/D-4569-2009; Wedin, David/K-4093-2012; Tjoelker, Mark/M-2413-2016; OI Craine, Joseph/0000-0001-6561-3244; Tjoelker, Mark/0000-0003-4607-5238; Ellsworth, David/0000-0002-9699-2272 NR 29 TC 322 Z9 352 U1 15 U2 160 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 12 PY 2001 VL 410 IS 6830 BP 809 EP 812 DI 10.1038/35071062 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 420TT UT WOS:000168021900053 PM 11298447 ER PT J AU Ruteshouser, EC Ashworth, LK Huff, V AF Ruteshouser, EC Ashworth, LK Huff, V TI Absence of PPP2R1A mutations in Wilms tumor SO ONCOGENE LA English DT Article DE PPP2R1A; protein phosphatase 2A; Wilms tumor; FWT2; tumor suppressor ID PROTEIN PHOSPHATASE 2A; BETA-CATENIN; SUPPRESSOR LOCUS; OKADAIC ACID; PPP1R3 GENE; SUBUNIT; EXPRESSION; ANTIGEN; CANCER; AXIN AB Evidence from genetic linkage analysis indicates that a gene located at 19q13.4, FWT2, is responsible for predisposition to Wilms tumor in many Wilms tumor families. This region has also been implicated in the etiology of sporadic Wilms tumor through loss of heterozygosity analyses, The PPP2R1A gene, encoding the alpha isoform of the heterotrimeric serine/threonine protein phosphatase 2A (PP2A), is located within the FWT2 candidate region and is altered in breast and lung carcinomas. PPP2R1B, encoding the beta isoform, is mutated in Lung, colon, and breast cancers. These findings suggested that both PPP2R1A and PPP2R1B may be tumor suppressor genes. Additionally, PP2A is important in fetal kidney growth and differentiation and has an expression pattern similar to that of the Wilms tumor suppressor gene WT1, Since PPP2R1A was therefore a compelling candidate for the FWT2 gene, we analysed the coding region of PPP2R1A in DNA and RNA samples from affected members of four Wilms tumor families and 30 sporadic tumors and identified no mutations in PPP2R1A in any of these 34 samples. We conclude that PPP2R1A is not the 19q familial Wilms tumor gene and that mutation of PPP2R1A is not a common event in the etiology of sporadic Wilms tumor. C1 Univ Texas, MD Anderson Canc Ctr, Dept Expt Pediat, Houston, TX 77030 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Huff, V (reprint author), Univ Texas, MD Anderson Canc Ctr, Dept Expt Pediat, 1515 Holcombe Blvd, Houston, TX 77030 USA. FU NCI NIH HHS [CA78257, CA16672, CA34936] NR 42 TC 8 Z9 8 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0950-9232 J9 ONCOGENE JI Oncogene PD APR 12 PY 2001 VL 20 IS 16 BP 2050 EP 2054 DI 10.1038/sj.onc.1204301 PG 5 WC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity GA 421CD UT WOS:000168043800013 PM 11360189 ER PT J AU Kodama, K Ushida, N Andreopoulos, C Saoulidou, N Tzanakos, G Yager, P Baller, B Boehnlein, D Freeman, W Lundberg, B Morfin, J Rameika, R Yun, JC Song, JS Yoon, CS Chung, SH Berghaus, P Kubantsev, M Reay, NW Sidwell, R Stanton, N Yoshida, S Aoki, S Hara, T Rhee, JT Ciampa, D Erickson, C Graham, M Heller, K Rusack, R Schwienhorst, R Sielaff, J Trammell, J Wilcox, J Hoshino, K Jiko, H Miyanishi, M Komatsu, M Nakamura, M Nakano, T Niwa, K Nonaka, N Okada, K Sato, O Akdogan, T Paolone V Rosenfeld, C Kulik, A Kafka, T Oliver, W Patzak, T Schneps, J AF Kodama, K Ushida, N Andreopoulos, C Saoulidou, N Tzanakos, G Yager, P Baller, B Boehnlein, D Freeman, W Lundberg, B Morfin, J Rameika, R Yun, JC Song, JS Yoon, CS Chung, SH Berghaus, P Kubantsev, M Reay, NW Sidwell, R Stanton, N Yoshida, S Aoki, S Hara, T Rhee, JT Ciampa, D Erickson, C Graham, M Heller, K Rusack, R Schwienhorst, R Sielaff, J Trammell, J Wilcox, J Hoshino, K Jiko, H Miyanishi, M Komatsu, M Nakamura, M Nakano, T Niwa, K Nonaka, N Okada, K Sato, O Akdogan, T Paolone, V Rosenfeld, C Kulik, A Kafka, T Oliver, W Patzak, T Schneps, J CA DONUT Collaboration TI Observation of tau neutrino interactions SO PHYSICS LETTERS B LA English DT Article ID OSCILLATION; SEARCH AB The DONUT experiment has analyzed 203 neutrino interactions recorded in nuclear emulsion targets. A decay search has found evidence of four tau neutrino interactions with an estimated background of 0.34 events. This number is consistent with the Standard Model expectation. (C) 2001 Published by Elsevier Science B.V. C1 Aichi Univ Educ, Kariya, Japan. Tufts Univ, Medford, MA 02155 USA. Univ S Carolina, Columbia, SC 29208 USA. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Nagoya Univ, Nagoya, Aichi 4648602, Japan. Univ Minnesota, Minneapolis, MN 55455 USA. Konkuk Univ, Seoul, South Korea. Kobe Univ, Kobe, Hyogo, Japan. Kansas State Univ, Manhattan, KS 66506 USA. Gyeongsang Univ, Chinju, South Korea. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Athens, Athens, Greece. RP Kodama, K (reprint author), Aichi Univ Educ, Kariya, Japan. EM lundberg@fnal.gov RI Aoki, Shigeki/L-6044-2015 NR 12 TC 167 Z9 167 U1 2 U2 7 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 APR 12 PY 2001 VL 504 IS 3 BP 218 EP 224 DI 10.1016/S0370-2693(01)00307-0 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 420BN UT WOS:000167984200003 ER PT J AU Daum, KA Atkinson, DA Ewing, RG Knighton, WB Grimsrud, EP AF Daum, KA Atkinson, DA Ewing, RG Knighton, WB Grimsrud, EP TI Resolving interferences in negative mode ion mobility spectrometry using selective reactant ion chemistry SO TALANTA LA English DT Article DE resolving interferences; negative mode ion mobility spectrometry selective reactant ion chemistry ID ATMOSPHERIC-PRESSURE; PLASMA CHROMATOGRAPHY; RATE CONSTANTS; CHLORIDE-ION; REAGENT IONS AB During the investigation of the degradation products of 2,4,6-trinitrotoluene (TNT) using ion mobility spectrometry (IMS), 2,4-dichlorophenoxyacetic acid (2.4-D) and 2,4-dichlorophenol (DCP) were found to have IMS responses which overlapped those of the TNT degradation products. It was observed that the Cl- reactant ion chemistry, often used for explosives analysis, was not always successful in resolving peak overlap of analytes and interferents. It is shown here that resolution of the analytes and interferences can sometimes be achieved using only air for the formation of reactant ions, at other times through the use of Br- as an alternative to Cl- for producing reactant: ions, and also through the promotion of adduct stability by lowering the IMS temperature. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Dept Chem & Biol Sci, Idaho Falls, ID 83415 USA. Montana State Univ, Dept Chem, Bozeman, MT 59717 USA. RP Daum, KA (reprint author), Idaho Natl Engn & Environm Lab, Dept Chem & Biol Sci, Idaho Falls, ID 83415 USA. NR 20 TC 22 Z9 22 U1 1 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-9140 J9 TALANTA JI Talanta PD APR 12 PY 2001 VL 54 IS 2 BP 299 EP 306 DI 10.1016/S0039-9140(00)00656-1 PG 8 WC Chemistry, Analytical SC Chemistry GA 426EG UT WOS:000168336400010 PM 18968252 ER PT J AU Stewart, FF Luther, TA Harrup, MK Lash, RP AF Stewart, FF Luther, TA Harrup, MK Lash, RP TI Reactions and polymerization of hexa-[3-tert-butyl-4-hydroxyphenoxy]cyclotriphosphazene: A new method for the preparation of soluble cyclomatrix phosphazene polymers SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE phosphazenes; cyclomatrix; polyester; cyclotriphosphazenes; hexa-[3-tert-butyl-4-hydroxyphenoxy]cyclotriphosphazene ID POLYPHOSPHAZENE; POLY(CYCLOPHOSPHAZENE-BENZOQUINONE); POLY(ORGANOPHOSPHAZENE)S; FUNCTIONALIZATION; ELECTROLYTES AB Novel cyclomatrix phosphazene-containing polyester polymers were synthesized through the reaction of a polyhydroxylated cyclotriphosphazene and a bifunctional acid chloride. To demonstrate the chemistry of the free hydroxyl of hexa-[3-tertbutyl-4-hydroxyphenoxy] cyclotriphosphazene, nucleophilic displacement reactions were performed with both acetic anhydride and alkyl chlorides. This work compares favorably to literature data for the chemistry of hexa- [4-hydroxyphenoxy] cyclotriphosphazene, whose hydroxyl is not hindered by an adjacent substituent. The hindered site of hexa- [3-tert-butyl-4-hydroxyphenoxy] cyclotriphosphazene was found to react with bidentate acid chlorides to yield new high polymers. The phosphazene-containing polyesters were observed to have good solubility in polar organic solvents. Characterization of these new materials was performed using dilute solution laser Light scattering techniques, thermal analysis, and NMR spectroscopy. (C) 2001 John Wiley & Sons, Inc. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Stewart, FF (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 23 TC 2 Z9 3 U1 1 U2 3 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD APR 11 PY 2001 VL 80 IS 2 BP 242 EP 251 PG 10 WC Polymer Science SC Polymer Science GA 404CU UT WOS:000167080500013 ER PT J AU Song, J Cheng, Q Kopta, S Stevens, RC AF Song, J Cheng, Q Kopta, S Stevens, RC TI Modulating artificial membrane morphology: pH-induced chromatic transition and nanostructural transformation of a bolaamphiphilic conjugated polymer from blue helical ribbons to red nanofibers SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ATOMIC-FORCE MICROSCOPY; LIPID TUBULES; SUPRAMOLECULAR ASSEMBLIES; DIACETYLENIC ALDONAMIDES; MOLECULAR ARCHITECTURE; LIPOSOMES; ACID; VESICLES; PHASE; ORDER AB Design and characterization of helical ribbon assemblies of a bolaamphiphilic conjugated polymer and their color-coded transformation into nanofibers are described. An L-glutamic acid modified bolaamphiphilic diacetylene lipid was synthesized and self-assembled into right-handed helical ribbons with micron scale length and nano scale thickness under mild conditions. The ribbon structures were further stabilized by polymerizing well-aligned diacetylene units to form bisfunctional polydiacetylenes (PDAs). Transitions from flat sheets to helical ribbons and tubes were observed by transmission electron microscopy. The helical ribbons appear to originate from the rupture of flat sheets along domain edges and the peeling off between stacked lipid layers. These results point to the applicability of chiral packing theory in bolaamphiphilic supramolecular assemblies. Contact mode atomic force microscopy observations revealed that high order existed in the surface packing arrangement. Hexagonal and pseudorectangular packings were observed in flat and twisted regions of the ribbons, respectively, suggesting a correlation between microscopic morphologies and nanoscopic packing arrangements. The tricarboxylate functionalities of the bolaamphiphilic lipid provide a handle for the manipulation of the bisfunctional PDAs' morphology. Increasing solution pH caused the fraying of helical ribbons into nanofibers accompanied by a sharp blue-to-red chromatic transition. A dramatic change in circular dichroism spectra was observed during this process, suggesting the loss of chirality in packing. A model is proposed to account for the pH-induced morphological change and chromatic transition. The color-coded transition between two distinct microstructures would be useful in the design of sensors and other "smart" nanomaterials requiring defined molecular templates. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. EM Quan_Cheng@lbl.gov; stevens@scripps.edu RI Cheng, Jason/C-6345-2011; Stevens, Raymond/K-7272-2015 OI Stevens, Raymond/0000-0002-4522-8725 NR 59 TC 138 Z9 139 U1 4 U2 65 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 APR 11 PY 2001 VL 123 IS 14 BP 3205 EP 3213 DI 10.1021/ja0035046 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 421RZ UT WOS:000168078500003 PM 11457054 ER PT J AU Stocking, EM Martinez, RA Silks, LA Sanz-Cervera, JF Williams, RM AF Stocking, EM Martinez, RA Silks, LA Sanz-Cervera, JF Williams, RM TI Studies on the biosynthesis of paraherquamide: Concerning the mechanism of the oxidative cyclization of l-isoleucine to beta-methylproline SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID PENICILLIUM-CHARLESII; ANTIPARASITIC AGENTS C1 Colorado State Univ, Dept Chem, Ft Collins, CO 80523 USA. Univ Calif Los Alamos Natl Lab, NIH Stable Isotope Resource, Los Alamos, NM 87545 USA. Univ Valencia, Fac Quim, Dept Quim Organ, E-46100 Burjassot, Spain. RP Williams, RM (reprint author), Colorado State Univ, Dept Chem, Ft Collins, CO 80523 USA. RI Sanz-Cervera, Juan/K-1095-2014 FU NCI NIH HHS [CA70375]; NCRR NIH HHS [RR 02231]; NIGMS NIH HHS [GM49631] NR 11 TC 23 Z9 23 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD APR 11 PY 2001 VL 123 IS 14 BP 3391 EP 3392 DI 10.1021/ja005655e PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 421RZ UT WOS:000168078500034 PM 11457085 ER PT J AU Zhang, HL Sampson, DH AF Zhang, HL Sampson, DH TI Effective collision strengths with inclusion of resonance for hyperfine-structure transitions in H- and Li-like ions SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE atomic processes; line : formation AB Calculations are made of the resonance contribution to electron-impact excitation of H-like C-13 and Li-like Na-23, Mg-25, Al-27 and Si-29 to the upper hyperfine levels that produce millimetre (mm) lines of likely astrophysical interest. The resonance contribution is found to be very important for these Li-like ions, considerably more important than for Li-like Fe-57 considered previously, However, resonances are found to be rather unimportant for H-like C-13. The effect of radiative decay on the resonance contribution is found to be insignificant in all of the present calculations. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. RP Zhang, HL (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, POB 1663, Los Alamos, NM 87545 USA. NR 5 TC 3 Z9 3 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 11 PY 2001 VL 322 IS 3 BP 433 EP 437 DI 10.1046/j.1365-8711.2001.04054.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 422NZ UT WOS:000168126300001 ER PT J AU Rawlings, S Eales, S Lacy, M AF Rawlings, S Eales, S Lacy, M TI A sample of 6C radio sources with virtually complete redshifts - II. Optical spectroscopy SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; quasars : general; radio continuum : galaxies ID SOURCE COUNTS; ZONE 30-DEGREES-LESS-THAN-DELTA-LESS-THAN-51-DEGREES; LUMINOSITY FUNCTION; EMPTY FIELDS; GALAXIES; IDENTIFICATIONS; EVOLUTION; PEAK; 1-JY; CANDIDATES AB This is the second of two papers presenting basic observational data on the 6CE sample of extragalactic radio sources. It presents the results of optical spectroscopy which has yielded virtually complete redshift information for the 6CE sample: 56 of the 59 sample members have spectroscopic redshifts that, with the exception of eight cases, are secure. The redshift distribution N(z) is fairly flat over the redshift range 0 less than or equal to z < 2, with a median redshift of 1.1 and a high-redshift tail reaching to z = 3.4. The highest redshift (z > 1.75) members of the 6CE sample have similar optical spectra and a tight (less than one dex) spread in narrow-Ly alpha emission-line luminosity. C1 Univ Oxford, Dept Phys, Oxford OX1 3RH, England. Cardiff Univ, Dept Phys & Astron, Cardiff CF2 3YB, S Glam, Wales. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Univ Oxford, Dept Phys, Keble Rd, Oxford OX1 3RH, England. EM s.rawlings1@physics.ox.ac.uk NR 48 TC 51 Z9 51 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 11 PY 2001 VL 322 IS 3 BP 523 EP 535 DI 10.1046/j.1365-8711.2001.04151.x PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 422NZ UT WOS:000168126300008 ER PT J AU Willott, CJ Rawlings, S Blundell, KM Lacy, M Eales, SA AF Willott, CJ Rawlings, S Blundell, KM Lacy, M Eales, SA TI The radio luminosity function from the low-frequency 3CRR, 6CE and 7CRS complete samples SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; galaxies : evolution; quasars : general; radio continuum : galaxies ID VIRTUALLY COMPLETE REDSHIFTS; NORTH ECLIPTIC CAP; COSMOLOGICAL EVOLUTION; SOURCE COUNTS; OPTICAL SPECTROSCOPY; 151 MHZ; 1.4 GHZ; GALAXIES; QUASARS; CUTOFF AB We measure the radio luminosity function (RLF) of steep-spectrum radio sources using three redshift surveys of flux-limited samples selected at low (151 and 178 MHz) radio frequency, low-frequency source counts and the local RLF. The redshift surveys used are the new 7C Redshift Survey (7CRS) and the blighter 3CRR and 6CE surveys totalling 356 sources with virtually complete redshift z information, This yields unprecedented coverage of the radio luminosity versus z plane for steep-spectrum sources, and hence the most accurate measurements of the steep-spectrum RLF yet made, We find that a simple dual-population model for the RLF fits the data well, requiring differential density evolution (with z) for the two populations. The low-luminosity population can be associated with radio galaxies with weak emission lines, and includes sources with both FRI and FRII radio structures; its comoving space density rho rises by about one dex between z - 0 and 1 but cannot yet be meaningfully constrained at higher redshifts. The high-luminosity population can be associated with radio galaxies and quasars with strong emission lines, and consists almost exclusively of sources with FRII radio structure; its rho rises by nearly three dex between z similar to 0 and 2, These results mirror the situation seen in X-ray and optically selected samples of AGN where: (i) low-luminosity objects exhibit a gradual rise in rho with z that crudely matches the rises seen in the rates of global star formation and galaxy mergers; and (ii) the density of high-luminosity objects rises much more dramatically. The integrated radio luminosity density of the combination of the two populations is controlled by the value of rho at the low-luminosity end of the RLF of the high-luminosity population a quantity which has been directly measured at z - 1 by the 7CRS, We argue that robust determination of this quantity at higher redshifts requires a new redshift survey based on a large (similar to 1000 source) sample about five times fainter than the 7CRS. C1 Univ Oxford, Dept Phys, Oxford OX1 3RH, England. Inst Astrofis Canarias, Tenerife 38200, Spain. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Wales Coll Cardiff, Dept Phys & Astron, Cardiff CF2 3YB, S Glam, Wales. RP Willott, CJ (reprint author), Univ Oxford, Dept Phys, Keble Rd, Oxford OX1 3RH, England. EM cjw@astro.ox.ac.uk NR 64 TC 195 Z9 195 U1 1 U2 2 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 11 PY 2001 VL 322 IS 3 BP 536 EP 552 DI 10.1046/j.1365-8711.2001.04101.x PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 422NZ UT WOS:000168126300009 ER PT J AU Jaros, JA AF Jaros, JA TI The search for B-s(0) oscillations at SLD SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on B-Physics at Hadron Machines CY SEP 13-18, 2000 CL MAAGAN, ISRAEL ID Z(0) DECAYS; ASYMMETRY AB The SLD experiment at the SLAG Linear Collider has updated three searches for the time dependence of B-5(0) oscillations. One search uses events with a reconstructed D, meson; a second search uses events with a lepton and a topologically identified charmed meson; and the third uses events in which both a secondary and tertiary vertex are distinguished. The combined analyses are sensitive to values of Deltam(s), the oscillation frequency up to 13.0 ps(-1). A preliminary maximum likelihood analysis excludes Deltam(s) < 7.6 ps(-1) and 11.8 < Deltam(s) < 14.8 ps(-1) at 95% CL. Including this data, the combined world data now imply Deltam(s) > 15.0 ps(-1) at 95% CL. and are not incompatible with a signal near the expected value. Deltam(s) similar to 15 ps(-1). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Jaros, JA (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd,Menlo Pk, Stanford, CA 94309 USA. NR 14 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 11 PY 2001 VL 462 IS 1-2 BP 102 EP 107 DI 10.1016/S0168-9002(01)00081-X PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 434DN UT WOS:000168800000015 ER PT J AU Zisman, MS AF Zisman, MS TI PEP-II operations report SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on B-Physics at Hadron Machines CY SEP 13-18, 2000 CL MAAGAN, ISRAEL AB PEP-II is a two-ring asymmetric B factory operating at the Gamma (4S) resonance. It was constructed by a SLAC-LBNL-LLNL collaboration. The collider comprises two rings, a High-Energy Ring (HER) storing 9 GeV electrons, and a Low-Energy Ring (LE R) storing 3.1 GeV positrons. Commissioning of the HER began in mid-1997 and commissioning of the LER began in mid-1998. First evidence for collisions was obtained on July 23, 1998. The BABAR detector was installed in early 1999, and commissioning with the detector commenced in May 1999. In the present run, which began in October 1999. the peak luminosity has reached 3.1 x 10(33)cm(-2)s(-1) and the integrated luminosity delivered is 25 m. In this paper we describe the startup experience and summarize the operational experience during fiscal year 2000 (from October 1999 through September 2000). Plans for luminosity upgrades are briefly described. Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Zisman, MS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 11 PY 2001 VL 462 IS 1-2 BP 132 EP 138 DI 10.1016/S0168-9002(01)00086-9 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 434DN UT WOS:000168800000020 ER PT J AU Lange, DJ AF Lange, DJ TI The EvtGen particle decay simulation package SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on B-Physics at Hadron Machines CY SEP 13-18, 2000 CL MAAGAN, ISRAEL DE Monte Carlo; event generator ID PHYSICS AB With several new B-physics experiments now taking data, the physics of B-meson decays will be studied in greater detail than previously possible. It is important to have a simulation of the underlying physics processes that is able to accurately describe this data. The EvtGen package provides a framework for the implementation of physics processes relevant to decays of B mesons and other resonances. Models of time dependent CP asymmetries in neutral B meson decays. semileptonic form-factor models, and a full decay table for B decays are a few of the implemented features. (C) 2001 Published by Elsevier Science B.V. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Lange, DJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 7 TC 991 Z9 993 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 11 PY 2001 VL 462 IS 1-2 BP 152 EP 155 DI 10.1016/S0168-9002(01)00089-4 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 434DN UT WOS:000168800000023 ER PT J AU Gutierrez, G AF Gutierrez, G TI DO prospects for run II physics SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on B-Physics at Hadron Machines CY SEP 13-18, 2000 CL MAAGAN, ISRAEL DE Tevatron; DO experiment; b quark; CP violation; FCNC; rare decays AB Run II at the Tevatron will begin in the spring of 2001. With p (p) over bar collisions at roots = 2.0 TeV and an expected instantaneous luminosity of 2 x 10(32) cm(-2) s(-1), DO is expecting to collect an integrated luminosity of 2 fb(-1) in the first 2 years of running. The ongoing upgrade of the detector will allow the experiment not only to take full advantage of the high luminosity but will also allow for a rich B physics program at DO. In this paper the prospects for some important B physics measurements will be reviewed. These measurements include CP violation. B-s mixing, rare B decays, and lifetimes and mass measurements of bottom particles such as the A(b) and B-c. (C) 2001 Published by Elsevier Science B.V. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Gutierrez, G (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 11 PY 2001 VL 462 IS 1-2 BP 174 EP 178 DI 10.1016/S0168-9002(01)00094-8 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 434DN UT WOS:000168800000028 ER PT J AU Lehnert, NM Allen, DL Allen, BL Catasti, P Shiflett, PR Chen, M Lehnert, BE Gupta, G AF Lehnert, NM Allen, DL Allen, BL Catasti, P Shiflett, PR Chen, M Lehnert, BE Gupta, G TI Structure-based design of a bispecific receptor mimic that inhibits T cell responses to a superantigen SO BIOCHEMISTRY LA English DT Article ID STAPHYLOCOCCAL ENTEROTOXIN-B; BETA CHAIN; CLASS-II; BINDING AB Key surface proteins of pathogens and their toxins bind to the host. cell receptors in a manner that is quite different from the way the natural ligands bind to the same receptors and direct normal. cellular responses. Here we describe a novel strategy for "non-antibody-based" pathogen countermeasure by targeting the very same "alternative mode of host receptor binding" that the pathogen proteins exploit to cause infection and disease. We have chosen the Staphylococcus enterotoxin B (SEB) superantigen as a model pathogen protein to illustrate the principle and application of our strategy. SEB bypasses the normal route of antigen processing by binding as an intact protein to the complex formed by the MHC class II receptor on the antigen-presenting cell and the T cell receptor. This alternative mode of binding causes massive IL-2 release and T cell proliferation. A normally processed antigen requires all the domains of the receptor complex for its binding, whereas SEB requires only the alpha1 subunit (DR alpha) of the MHC class II receptor and the variable beta subunit (TCRV beta) of the T cell receptor. This prompted us to design a bispecific chimera, DR alpha -linker-TCRV beta, that acts as a receptor mimic and prevents the interaction of SEB with its host cell receptors. We have adopted (GSTAPPA)(2) as the linker sequence because it supports synergistic binding of DRa and TCRV beta to SEB and thereby makes DR alpha-(GSTAPPA)(2)-TCRV beta as effective an SEB binder as the native MHC class II-T cell receptor complex. Finally, we show that DR alpha-(GSTAPPA)(2)-TCRV beta inhibits SEB-induced IL-2 release and T cell proliferation at nanomolar concentrations. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. TExas BioGene Inc, Richardson, TX 75081 USA. RP Gupta, G (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, Mail Stop M888, Los Alamos, NM 87545 USA. NR 17 TC 18 Z9 19 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD APR 10 PY 2001 VL 40 IS 14 BP 4222 EP 4228 DI 10.1021/bi002172e PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 423VL UT WOS:000168198400004 PM 11284677 ER PT J AU Doyle, SA Beernink, PT Koshland, DE AF Doyle, SA Beernink, PT Koshland, DE TI Structural basis for a change in substrate specificity: Crystal structure of S113E isocitrate dehydrogenase in a complex with isopropylmalate, Mg2+, and NADP SO BIOCHEMISTRY LA English DT Article ID ESCHERICHIA-COLI; 3-ISOPROPYLMALATE DEHYDROGENASE; KINETIC MECHANISM; PHOSPHORYLATION; RESOLUTION; ERRORS; EVOLUTION; BINDING; ENZYME; MAPS AB Isocitrate dehydrogenase (IDH) catalyzes the oxidative decarboxylation of isocitrate and has negligible activity toward other (R)-malate-type substrates. The S113E mutant of IDH significantly improves its ability to utilize isopropylmalate as a substrate and switches the substrate specificity (k(cat)/K-M) from isocitrate to isopropylmalate. To understand the structural basis for this switch in substrate specificity, we have determined the crystal. structure of IDH S113E in a complex with isopropylmalate, NADP, and Mg2+ to 2.0 Angstrom resolution. On the basis of a comparison with previously determined structures, we identify distinct changes caused by the amino acid substitution and by the binding of substrates. The S113E complex exhibits alterations in global and active site conformations compared with other IDH structures that include loop and helix conformational changes near the active site. In addition, the angle of the hinge that relates the two domains was altered in this structure, which suggests that the S113E substitution and the binding of substrates act together to promote catalysis of isopropylmalate. Ligand binding results in reorientation of the active site helix that contains residues 113 through 116. E113 exhibits new interactions, including van der Waals contacts with the isopropyl group of isopropylmalate and a hydrogen bond with N115, which in turn forms a hydrogen bond with NADP. In addition, the loop and helix regions that bind NADP are altered, as is the loop that connects the NADP binding region to the active site helix, changing the relationship between substrates and enzyme. In combination, these interactions appear to provide the basis for the switch in substrate specificity. C1 Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Livermore, CA 94550 USA. RP Koshland, DE (reprint author), Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [GM 19582] NR 31 TC 17 Z9 18 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD APR 10 PY 2001 VL 40 IS 14 BP 4234 EP 4241 DI 10.1021/bi002533q PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 423VL UT WOS:000168198400006 PM 11284679 ER PT J AU Hindmarsh, AC Rotter, MD AF Hindmarsh, AC Rotter, MD TI Using an ODE solver for a class of integro-differential systems SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE integro-differential equations; Method of lines AB By a simple extension of the Method of Lines, the ordinary differential equation solver VODPK may be used to solve a certain class of integro-differential equation systems (IDE systems). The problems are characterized by a pair of advected frequency-dependent quantities, coupled to a population variable whose rate includes a spectral integral in one space dimension. We have found that with an appropriate choice of preconditioner to aid in the convergence of the linear iterations, an extremely efficient method is obtained for the solution of these types of IDE system problems. We discuss the semidiscretization process and the formation of the preconditioner in some detail. Finally, we present an application of the technique. (C) 2001 Academic Press. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Hindmarsh, AC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD APR 10 PY 2001 VL 168 IS 2 BP 267 EP 285 DI 10.1006/jcph.2000.6680 PG 19 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 425TL UT WOS:000168307700001 ER PT J AU Brown, DL Cortez, R Minion, ML AF Brown, DL Cortez, R Minion, ML TI Accurate projection methods for the incompressible Navier-Stokes equations SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE incompressible flow; projection method; boundary conditions ID FRACTIONAL-STEP METHOD; SCHEMES; APPROXIMATION; FLOWS AB This paper considers the accuracy of projection method approximations to the initial-boundary-value problem for the incompressible Navier-Stokes equations. The issue of how to correctly specify numerical boundary conditions for these methods has been outstanding since the birth of the second-order methodology a decade and a half ago. It has been observed that while the velocity can be reliably computed to second-order accuracy in time and space, the pressure is typically only first-order accurate in the L-infinity-norm. This paper identifies the source of this problem in the interplay of the global pressure-update formula with the numerical boundary conditions and presents an improved projection algorithm which is fully second-order accurate, as demonstrated by a normal mode analysis and numerical experiments. In addition, a numerical method based on a gauge variable formulation of the incompressible Navier-Stokes equations, which provides another option for obtaining fully second-order convergence in both velocity and pressure, is discussed. The connection between the boundary conditions for projection methods and the gauge method is explained in detail. (C) 2001 Academic Press. C1 Lawrence Livermore Natl Lab, Ctr Appl Sci COmp, Livermore, CA 94551 USA. Tulane Univ, Dept Math, New Orleans, LA 70118 USA. Univ N Carolina, Dept Math, Chapel Hill, NC 27599 USA. RP Lawrence Livermore Natl Lab, Ctr Appl Sci COmp, Livermore, CA 94551 USA. EM dlb@llnl.gov; cortez@math.tulane.edu; minion@amath.unc.edu RI Minion, Michael/B-2235-2008 NR 39 TC 368 Z9 385 U1 3 U2 45 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD APR 10 PY 2001 VL 168 IS 2 BP 464 EP 499 DI 10.1006/jcph.2001.6715 PG 36 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 425TL UT WOS:000168307700010 ER PT J AU Stauffer, P Bekins, BA AF Stauffer, P Bekins, BA TI Modeling consolidation and dewatering near the toe of the northern Barbados accretionary complex SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID FAULT-ZONE DILATION; DECOLLEMENT ZONE; RIDGE DECOLLEMENT; THRUST BELTS; FLUID-FLOW; HEAT-FLOW; PERMEABILITY; SEDIMENTS; WEDGES; PRISM AB At the toe of the northern Barbados accretionary complex, temperature and pore water chemistry data indicate that fluid flow is channeled along the decollement and other shallow thrust faults. We examine mechanisms that may prevent consolidation and maintain high permeability over large sections of the decollement. High-resolution bulk density data from five boreholes show that the decollement is well consolidated at some sites while other sites remain underconsolidated. Underconsolidated decollement behavior is associated with kilometer-scale negative-polarity seismic reflections from the decollement plane that have been interpreted to be fluid conduits. We use a coupled fluid flow/consolidation model to simulate the loading response of a 10-km-long by 680-m-thick slice of sediment as it enters the accretionary complex. The simulations capture 185 ka (5 km) of subduction, with a load function representing the estimated effective stress of the overriding accretionary prism (3.8 degrees taper angle). Simulation results of bulk density in the decollement 3.2 km arcward of the deformation front are compared with observations. The results show that persistent high pore pressures at the arcward edge of the simulation domain can explain underconsolidated behavior. The scenario is consistent with previous modeling results showing that high pore pressures can propagate intermittently along the decollement from deeper in the complex. Simulated seaward fluxes in the decollement (1-14 cm yr(-1)) lie between previous estimates from modeling studies of steady state (<1 cm yr(-1)) and transient (>1 m yr(-1)) flow. Maximum simulated instantaneous fluid sources (2.5 x 10 s(-1)) are comparable to previous estimates. The simulations show minor swelling of incoming sediments (fluid sources similar to -3 x 10(15) s(-1)) up to 3 km before subduction that may help to explain small-scale shearing and normal faulting proximal to the protodecollement. C1 US Geol Survey, Menlo Park, CA 94025 USA. Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. RP Stauffer, P (reprint author), Univ Calif Los Alamos Natl Lab, TA-3 SM31 MS-C306, Los Alamos, NM 87545 USA. EM stauffer@vega.lanl.gov; babekins@usgs.gov OI Stauffer, Philip/0000-0002-6976-221X NR 49 TC 17 Z9 17 U1 0 U2 0 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 APR 10 PY 2001 VL 106 IS B4 BP 6369 EP 6383 DI 10.1029/2000JB900368 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 418XU UT WOS:000167920500003 ER PT J AU Stevens, MJ AF Stevens, MJ TI Interfacial fracture between highly cross-linked polymer networks and a solid surface: Effect of interfacial bond density SO MACROMOLECULES LA English DT Article ID EPOXIES AB For highly cross-linked polymer networks bonded to a solid surface, the effect of interfacial bond density and system size on interfacial fracture is studied using molecular dynamics simulations. Results for tensile and shear mode simulations are given. The correspondence between the stress-strain curve and the sequence of molecular deformations is obtained. The failure strain for a fully bonded surface is equal to the strain necessary to make taut the average of the minimal paths through the network from a bonded site on the bottom solid surface to a bonded site on the top surface. At fractional interfacial bond densities, cavities form above the nonbonded surface, yielding an inhomogeneous strain profile and a smaller failure strain. The failure strain and stress are linearly proportional to the number of bonds at the interface except in the tensile mode when number of bonds is so few that van der Waals interactions dominate. The failure mode is successfully constructed to be interfacial by limiting the interfacial bond density to be less than the bulk bond density. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, MS 1111,POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 73 Z9 73 U1 2 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD APR 10 PY 2001 VL 34 IS 8 BP 2710 EP 2718 DI 10.1021/ma000553u PG 9 WC Polymer Science SC Polymer Science GA 419TK UT WOS:000167964600045 ER PT J AU Fang, XW Golden, BL Littrell, K Shelton, V Thiyagarajan, P Pan, T Sosnick, TR AF Fang, XW Golden, BL Littrell, K Shelton, V Thiyagarajan, P Pan, T Sosnick, TR TI The thermodynamic origin of the stability of a thermophilic ribozyme SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID SUBTILIS RNASE-P; SMALL-ANGLE SCATTERING; CRYSTAL-STRUCTURE; RIBONUCLEASE-P; ANGSTROM RESOLUTION; SUBSTRATE-BINDING; DOMAIN; TEMPERATURE; SECONDARY; PERSPECTIVE AB Understanding the mechanism of thermodynamic stability of an RNA structure has significant implications for the function and design of RNA. We investigated the equilibrium folding of a thermophilic ribozyme and its mesophilic homologue by using hydroxyl radical protection, small-angle x-ray scattering, and circular dichroism. Both RNAs require Mg2+ to fold to their native structures that are very similar. The stability is measured as a function of Mg2+ and urea concentrations at different temperatures. The enhanced stability of the thermophilic ribozyme primarily is derived from a tremendous increase in the amount of structure formed in the ultimate folding transition. This increase in structure formation and cooperativity arises because the penultimate and the ultimate folding transitions in the mesophilic ribozyme become linked into a single transition in the folding of the thermophilic ribozyme. Therefore, the starting point, or reference state, for the transition to the native, functional thermophilic ribozyme is significantly less structured. The shift in the reference state, and the resulting increase in folding cooperativity, is likely due to the stabilization of selected native interactions that only form in the ultimate transition. This mechanism of using a less structured intermediate and increased cooperativity to achieve higher functional stability for tertiary RNAs is fundamentally different from that commonly proposed to explain the increased stability of thermophilic proteins. C1 Univ Chicago, Dept Biochem & Mol Biol, Chicago, IL 60637 USA. Purdue Univ, Dept Biochem, W Lafayette, IN 47907 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Chicago, Dept Chem, Chicago, IL 60637 USA. Univ Chicago, Inst Biophys Dynam, Chicago, IL 60637 USA. RP Sosnick, TR (reprint author), Univ Chicago, Dept Biochem & Mol Biol, 920 E 58Th St, Chicago, IL 60637 USA. RI ID, BioCAT/D-2459-2012; Littrell, Kenneth/D-2106-2013; OI Littrell, Kenneth/0000-0003-2308-8618; Golden, Barbara/0000-0002-9741-882X FU NIGMS NIH HHS [R01 GM057880, R01GM57880] NR 35 TC 51 Z9 56 U1 1 U2 5 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 APR 10 PY 2001 VL 98 IS 8 BP 4355 EP 4360 DI 10.1073/pnas.071050698 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 421HV UT WOS:000168059700020 PM 11296284 ER PT J AU Miyashita, M Presley, JM Buchholz, BA Lam, KS Lee, YM Vogel, JS Hammock, BD AF Miyashita, M Presley, JM Buchholz, BA Lam, KS Lee, YM Vogel, JS Hammock, BD TI Attomole level protein sequencing by Edman degradation coupled with accelerator mass spectrometry SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID LIQUID-CHROMATOGRAPHY; ATRAZINE METABOLITES; HUMAN URINE; PEPTIDE; GELS; MS; PERFORMANCE; SENSITIVITY; EXPOSURE; BINDING AB Edman degradation remains the primary method for determining the sequence of proteins. In this study, accelerator mass spectrometry was used to determine the N-terminal sequence of glutathione S-transferase at the attomole level with zeptomole precision using a tracer of C-14. The transgenic transferase was labeled by growing transformed Escherichia coli on [C-14]glucose and purified by microaffinity chromatography. An internal standard of peptides on a solid phase synthesized to release approximately equal amounts of all known amino acids with each cycle were found to increase yield of gas phase sequencing reactions and subsequent semimicrobore HPLC as did a lactoglobulin carrier, This method is applicable to the sequencing of proteins from cell culture and illustrates a path to more general methods for determining N-terminal sequences with high sensitivity. C1 Univ Calif Davis, Dept Entomol, Livermore, CA 95616 USA. Univ Calif Davis, Mol Struct Facil, Livermore, CA 95616 USA. Univ Calif Davis, Ctr Canc, Livermore, CA 95616 USA. Univ Calif Davis, Dept Internal Med, Livermore, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. RP Hammock, BD (reprint author), Univ Calif Davis, Dept Entomol, 1 Shields Ave, Livermore, CA 95616 USA. RI Buchholz, Bruce/G-1356-2011 FU NIEHS NIH HHS [P42 ES004699, P30 ES05707, P30 ES005707, P42 ES04699, R01 ES02710, R01 ES002710] NR 28 TC 27 Z9 27 U1 0 U2 5 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 APR 10 PY 2001 VL 98 IS 8 BP 4403 EP 4408 DI 10.1073/pnas.071047998 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 421HV UT WOS:000168059700028 PM 11287636 ER PT J AU Stampfer, MR Garbe, J Levine, G Lichtsteiner, S Vasserot, AP Yaswen, P AF Stampfer, MR Garbe, J Levine, G Lichtsteiner, S Vasserot, AP Yaswen, P TI Expression of the telomerase catalytic subunit, hTERT, induces resistance to transforming growth factor beta growth inhibition in p16(INK4A)(-) human mammary epithelial cells SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID HUMAN FIBROBLASTS; P16 INACTIVATION; TUMOR-CELLS; LIFE-SPAN; IMMORTALIZATION; SENESCENCE; CONVERSION; CANCER; INDUCTION; CAPACITY AB Failures to arrest growth in response to senescence or transforming growth factor beta (TGF-beta) are key derangements associated with carcinoma progression. We report that activation of telomerase activity may overcome both inhibitory pathways. Ectopic expression of the human telomerase catalytic subunit, hTERT, in cultured human mammary epithelial cells (HMEC) lacking both telomerase activity and p16(INK4A) resulted in gaining the ability to maintain indefinite growth in the absence and presence of TGF-beta. The ability to maintain growth in TGF-beta was independent of telomere length and required catalytically active telomerase capable of telomere maintenance in vivo. The capacity of ectopic hTERT to induce TGF-beta resistance may explain our previously described gain of TGF-beta resistance after reactivation of endogenous telomerase activity in rare carcinogen-treated HMEC. In those HMEC that overcame senescence, both telomerase activity and TGF-beta resistance were acquired gradually during a process we have termed conversion. This effect of hTERT may model a key change occurring during in vivo human breast carcinogenesis. C1 Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. Geron Corp, Menlo Park, CA 92045 USA. RP Stampfer, MR (reprint author), Lawrence Berkeley Natl Lab, Div Life Sci, Bldg 70A-1118,1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NCI NIH HHS [CA-24844] NR 28 TC 103 Z9 104 U1 0 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 APR 10 PY 2001 VL 98 IS 8 BP 4498 EP 4503 DI 10.1073/pnas.071483998 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 421HV UT WOS:000168059700044 PM 11287649 ER PT J AU Puntes, VF Krishnan, KM Alivisatos, P AF Puntes, VF Krishnan, KM Alivisatos, P TI Synthesis, self-assembly, and magnetic behavior of a two-dimensional superlattice of single-crystal epsilon-Co nanoparticles SO APPLIED PHYSICS LETTERS LA English DT Article ID NANOCRYSTAL SUPERLATTICES; METAL-CLUSTERS; THIN-FILMS; ORGANIZATION; PARTICLES AB A method of producing high-quality magnetic colloidal dispersions by the rapid pyrolysis of cobalt carbonyl in an inert atmosphere was employed to produce monodispersed, stabilized, defect-free epsilon -cobalt nanocrystals, with spherical shapes and sizes ranging from 3 to 17 nm. The size distribution and the shape of the nanocrystals were controlled by varying the surfactant (oleic acid, phosphonic oxides and acids, etc.), its concentration, and the reaction temperature. These particles have been observed to produce two-dimensional self-assemblies when evaporated at low rates in a controlled atmosphere. A collective behavior due to dipolar interactions has been observed in the low susceptibility measurements corresponding to a highly ordered fine particles system. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Puntes, VF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Puntes, Victor/F-8407-2013; Alivisatos , Paul /N-8863-2015 OI Puntes, Victor/0000-0001-8996-9499; Alivisatos , Paul /0000-0001-6895-9048 NR 24 TC 241 Z9 245 U1 7 U2 84 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 9 PY 2001 VL 78 IS 15 BP 2187 EP 2189 DI 10.1063/1.1362333 PG 3 WC Physics, Applied SC Physics GA 418GA UT WOS:000167881500032 ER PT J AU Wang, PX Ho, YK Yuan, XQ Kong, Q Cao, N Sessler, AM Esarey, E Nishida, Y AF Wang, PX Ho, YK Yuan, XQ Kong, Q Cao, N Sessler, AM Esarey, E Nishida, Y TI Vacuum electron acceleration by an intense laser SO APPLIED PHYSICS LETTERS LA English DT Article ID RELATIVISTIC ENERGIES; VIOLENT ACCELERATION; PULSES; PLASMAS; FIELD; BEAM; SCATTERING; ULTRASHORT AB Using three dimensional test particle simulations, the characteristics and essential conditions under which an electron, in a vacuum laser beam, can undergo a capture and acceleration scenario (CAS) have been examined. When a(0)greater than or similar to 100 the electron can be captured and violently accelerated to energies greater than or similar to1 GeV, with an acceleration gradient greater than or similar to 10 GeV/cm, where a(0)=eE(0)/m(e)omegac is the normalized laser field amplitude. The physical mechanism behind the CAS is that diffraction of the focused laser beam leads to a slowing down of the effective wave phase velocity along the captured electron trajectory, such that the electron can be trapped in the acceleration phase of the wave for a longer time and thus gain significant energy from the field. (C) 2001 American Institute of Physics. C1 Fudan Univ, Inst Modern Phys, Shanghai 200433, Peoples R China. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Utsunomiya Univ, Grad Sch Engn, Dept Energy & Environm Sci, Utsunomiya, Tochigi 321, Japan. RP Ho, YK (reprint author), Fudan Univ, Inst Modern Phys, Shanghai 200433, Peoples R China. NR 28 TC 104 Z9 107 U1 2 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 9 PY 2001 VL 78 IS 15 BP 2253 EP 2255 DI 10.1063/1.1359486 PG 3 WC Physics, Applied SC Physics GA 418GA UT WOS:000167881500054 ER PT J AU Hopkins, TA Berg, JM Costa, DA Smith, WH Dewey, HJ AF Hopkins, TA Berg, JM Costa, DA Smith, WH Dewey, HJ TI Spectroscopy of UO2Cl42- in basic aluminum chloride 1-ethyl-3-methylimidazolium chloride SO INORGANIC CHEMISTRY LA English DT Article ID ELECTRONIC-STRUCTURE; SINGLE-CRYSTALS; IONIC LIQUIDS; ELECTROCHEMISTRY; CS2UO2CL4; SPECTRUM; UO22+ AB The optical absorption, emission, FT Raman, one-photon excitation, two-photon excitation, and luminescence lifetime measurements are reported for UO2Cl42- in 40:60 AlCl3-EMIC (where EMIC equivalent to 1-ethyl-3-methylimidazolium chloride), a room-temperature ionic liquid. Comparison of the spectra with previous results from single crystals containing UO2Cl42- allowed the characterization of four ground-state vibrational frequencies, two excited-state vibrational frequencies, and the location of eight electronic excited-state energy levels. The vibrational frequencies and electronic energy levels are found to be consistent with the UO2Cl42- ion. Comparison of the one-photon and two-photon excitation spectra, and the relative intensities of the transitions in the emission spectrum indicate that the center of symmetry is perturbed by an interaction with the solvent. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dewey, HJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 33 Z9 34 U1 1 U2 10 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 APR 9 PY 2001 VL 40 IS 8 BP 1820 EP 1825 DI 10.1021/ic001027m PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 420DK UT WOS:000167988500017 PM 11312737 ER PT J AU Luo, QH Howell, RC Dankova, M Bartis, J Williams, CW Horrocks, WD Young, VG Rheingold, AL Francesconi, LC Antonio, MR AF Luo, QH Howell, RC Dankova, M Bartis, J Williams, CW Horrocks, WD Young, VG Rheingold, AL Francesconi, LC Antonio, MR TI Coordination of rare-earth elements in complexes with monovacant Wells-Dawson polyoxoanions SO INORGANIC CHEMISTRY LA English DT Article ID ABSORPTION FINE-STRUCTURE; POLYOXOMETALATE OXIDATION CATALYSTS; AQUEOUS CHLORIDE SOLUTIONS; MOLECULAR-WEIGHT AMINES; P-31 NMR-SPECTROSCOPY; X-RAY-DIFFRACTION; LANTHANIDE COMPLEXES; ACID-SOLUTIONS; FORMATION-CONSTANTS; CRYSTAL-STRUCTURES AB The alpha -1 and alpha -2 isomers of the monovacant Wells-Dawson heteropolyoxoanion [P2W17O61](10-) are complexants of trivalent rare-earth (RE) ions and serve to stabilize otherwise reactive tetravalent lanthanide (Ln) and actinide (An) ions in aqueous solution. Aspects of the bonding of Ln ions with alpha -1-[P2W17O61](10-) and alpha -2-[P2W17O61](10-) were investigated to address issues of complex formation and stability. We present structural insights about the Ln(III) coordination environment and hydration in two types of stoichiometric complexes, [Ln(alpha -1-P2W17O61)](7-) and [Ln(alpha -2-X2W17O61)(2)](17-) (for Ln drop Sm, Eu, Lu; X drop P, As). The crystal and molecular structures of C(H2O)(4)-Lu(alpha -1-P2W17O61)(2)](17-) (1) and [Lu(alpha -2-P2W17O61)(2)](17-) (2) were solved and refined through use of single-crystal X-ray diffraction. The crystallographic results are supported with corresponding insights from XAFS (X-ray absorption fine structure) for a series of nine solid-state complexes as well as from optical luminescence spectroscopy of the Eu(III) analogues in aqueous solution. All the Ln ions are eight-coordinate with oxygen atoms in a square antiprism arrangement. For the 1:1 stoichiometric Ln/alpha -1-[P2W17O61](10-) complexes, the Ln ions are bound to four O atoms of the lacunary polyoxometalate framework in addition to four O atoms from solvent (water) molecules as I(H2O)(4)Ln(alpha -1-P2W17O61)](7-) This structure (1) is the first of its kind for any metal complex of alpha -1-[P2W17O61](10-), and the data indicate that the general stoichiometry [(H2O)(4)Ln(alpha -1-P2W17O61)](7-) is maintained throughout the lanthanide series. For the 1:2 stoichiometric Ln/alpha -2-[X2W17O61](10-) complexes, no water molecules are in the Ln-Os coordination sphere. The Ln ions are bound to eight O atoms-four from each of two heteropolyanions-as [Ln(alpha -2-X2W17O61)21 (17-). The average Ln-O interatomic distances decrease across the lanthanide series, consistent with the decreasing Ln ionic radius. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. CUNY, Hunter Coll, Dept Chem, New York, NY 10021 USA. CUNY, Grad Sch, New York, NY 10021 USA. Univ Delaware, Dept Chem, Newark, DE 19716 USA. Univ Minnesota, Dept Chem, Xray Crystallog Lab, Minneapolis, MN 55455 USA. Penn State Univ, Dept Chem, University Pk, PA 16802 USA. RP Francesconi, LC (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. FU NCRR NIH HHS [RR03037-08] NR 74 TC 100 Z9 102 U1 3 U2 38 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 APR 9 PY 2001 VL 40 IS 8 BP 1894 EP 1901 DI 10.1021/ic001427+ PG 8 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 420DK UT WOS:000167988500027 PM 11312747 ER PT J AU Perez, GE Sohler, D Algora, A Dombradi, Z Nyako, BM Timar, J Zolnai, L Wyss, R Cederkall, J Johnson, A Kerek, A Klamra, W Norlin, LO Lipoglavsek, M Fahlander, C Likar, A Palacz, M Atac, A Nyberg, J Persson, J Gizon, A Gizon, J Boston, AJ Paul, ES Grawe, H Schubart, R Joss, DT Juutinen, S Makela, E Kownacki, J de Poli, M Bednarczyk, P de Angelis, G Seweryniak, D Foltescu, D Roth, HA Skeppstedt, O Jerrestam, D Shizuma, T Sletten, G Tormanen, S AF Perez, GE Sohler, D Algora, A Dombradi, Z Nyako, BM Timar, J Zolnai, L Wyss, R Cederkall, J Johnson, A Kerek, A Klamra, W Norlin, LO Lipoglavsek, M Fahlander, C Likar, A Palacz, M Atac, A Nyberg, J Persson, J Gizon, A Gizon, J Boston, AJ Paul, ES Grawe, H Schubart, R Joss, DT Juutinen, S Makela, E Kownacki, J de Poli, M Bednarczyk, P de Angelis, G Seweryniak, D Foltescu, D Roth, HA Skeppstedt, O Jerrestam, D Shizuma, T Sletten, G Tormanen, S TI Structure of high-spin states in Pd-100 SO NUCLEAR PHYSICS A LA English DT Article DE Cr-50(Ni-58,4p alpha) and Zn-70(S-36,6n) reactions; NORDBALL and EUROGAM II gamma-ray spectrometers; measured E-gamma, I-gamma, particle-gamma gamma and gamma gamma coincidences, gamma-ray angular correlation and linear polarisation; deduced Pd-100 levels, I, pi, gamma-ray multipolarities; terminating bands; total routhian surface plus cranked shell model ID GAMMA-RAY SPECTROSCOPY; TERMINATING BANDS; EXCITED-STATES; NEUTRON; NUCLEI; RU-98,RU-99,RU-100; INFORMATION; NORDBALL; DETECTOR; ARRAY AB High-spin states of the neutron deficient (100)pd nucleus have been investigated via the Cr-50(Ni-58, 4p alpha) and Zn-70(S-36,6n) heavy-ion induced reactions. For the detection of evaporated particles and gamma rays the NORDBALL array equipped with ancillary detectors and the EUROGAM II detector system were utilized. By the use of in-beam spectroscopic methods 89 transitions belonging to (100)pd have been observed, 49 of which were identified for the first time. The level scheme has been extended up to E-X approximate to 16 MeV excitation energy and I approximate to 25h. The experimental results were compared with the predictions of cranked shell model calculations. Maximal spin alignments were found in the (pig(9/2))(12+)(-4) (vd(5/2),g(7/2)(3)h(11/2))(13-) and (pig(9/2)(-3)p(1/2))(11-)(vd(5/2)g(7/2)(3)h(11/2))(13-) configurations. Possible existence of octupole correlations is discussed on the basis of 6 (E 1)lB(E2) values deduced for the decays of high-spin levels in the yrast negative-parity band. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Inst Nucl Res, H-4001 Debrecen, Hungary. Royal Inst Technol, Dept Phys, S-10044 Stockholm, Sweden. Univ Lund, Dept Cosm & Subatom Phys, Lund, Sweden. Jozef Stefan Inst, Ljubljana, Slovenia. Soltan Inst Nucl Phys, Swierk, Poland. Uppsala Univ, Dept Neutron Res, Uppsala, Sweden. Inst Sci Nucl, Grenoble, France. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 3BX, Merseyside, England. Gesell Schwerionenforsch, Darmstadt, Germany. Staffordshire Univ, Sch Sci, Stoke On Trent ST4 2DE, Staffs, England. Univ Jyvaskyla, Dept Phys, Jyvaskyla, Finland. Univ Warsaw, Heavy Ion Lab, Warsaw, Poland. Lab Nazl Legnaro, Padua, Italy. Argonne Natl Lab, Argonne, IL 60439 USA. Chalmers Univ Technol, S-41296 Gothenburg, Sweden. Uppsala Univ, Dept Neutron Res, Nykoping, Sweden. Univ Copenhagen, Niels Bohr Inst, Copenhagen, Denmark. RP Nyako, BM (reprint author), Inst Nucl Res, Pf-51, H-4001 Debrecen, Hungary. RI Dombradi, Zsolt/B-3743-2012; Algora, Alejandro/E-2960-2015; Palacz, Marcin/H-3713-2012 OI Algora, Alejandro/0000-0002-5199-1794; NR 39 TC 14 Z9 16 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 APR 9 PY 2001 VL 686 BP 41 EP 63 DI 10.1016/S0375-9474(00)00513-3 PG 23 WC Physics, Nuclear SC Physics GA 413TW UT WOS:000167628800003 ER PT J AU Kaplan, M Copi, CJ DeYoung, PA Gilfoyle, GJ Karol, PJ Moses, DJ Parker, WE Rehm, KE Sarafa, J Vardaci, E AF Kaplan, M Copi, CJ DeYoung, PA Gilfoyle, GJ Karol, PJ Moses, DJ Parker, WE Rehm, KE Sarafa, J Vardaci, E TI Studies of light charged particle emission from fission and ER reactions in the system 344 MeV Si-28+Sb-121 -> Tb-149 (E*=240 MeV) SO NUCLEAR PHYSICS A LA English DT Article ID 280 MEV AR-40+AL-27; 670 MEV MN-55+C-12; FE-56+AU-197 REACTIONS; NUCLEI; KR-86+CU-63; DEFORMATIONS; DEEXCITATION; SB-121+AL-27; EVAPORATION; MECHANISMS AB Light charged particles (LCP) have been measured for the reaction 344 MeV Si-28 + Sb-121 in singles and in coincidence with evaporation residues (ER), fusion-fission fragments (FF), and other LCP. A major feature of this experiment was the use of a gas-filled magnetic spectrometer in the forward direction to separate ER From the much more abundant yield of elastically scattered projectiles and projectile-like fragments. The dominant sources of evaporative H-1 and He-4 emission are the ER (approximately 75%), with the remainder being largely associated with fission reactions. For these latter reactions, most of the H-1 and He-4 can be well accounted for by evaporation from the composite system prior to fission and by evaporation from the postfission fragments. LCP emission cross sections were determined fur each identified source, and a comparison has been made to previous studies, From this comparison, indications were found for significant entrance channel effects, with the more asymmetric channels exhibiting much larger LCF cross sections. Statistical model predictions for ER emissions are in good agreement with observed LCP energy spectra, angular distributions, and integrated inclusive and exclusive cross sections, with all calculations using the same unique set of model parameters. This result contrasts strongly with recent reports for light mass systems, where model calculations were unable to simultaneously reproduce all observables. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Carnegie Mellon Univ, Dept Chem, Pittsburgh, PA 15213 USA. Hope Coll, Dept Phys, Holland, MI 49423 USA. Univ Richmond, Dept Phys, Richmond, VA 23204 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kaplan, M (reprint author), Carnegie Mellon Univ, Dept Chem, 4400 5th Ave, Pittsburgh, PA 15213 USA. NR 31 TC 4 Z9 4 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 APR 9 PY 2001 VL 686 BP 109 EP 128 DI 10.1016/S0375-9474(00)00573-X PG 20 WC Physics, Nuclear SC Physics GA 413TW UT WOS:000167628800006 ER PT J AU Savage, MJ Springer, RP AF Savage, MJ Springer, RP TI The anapole form factor of the deuteron SO NUCLEAR PHYSICS A LA English DT Article ID EFFECTIVE-FIELD-THEORY; NUCLEON-NUCLEON-SCATTERING; SHORT-RANGE INTERACTIONS; NONRELATIVISTIC QUANTUM-MECHANICS; EFFECTIVE CHIRAL LAGRANGIANS; LOW-ENERGY THEOREMS; PARITY NONCONSERVATION; NN SCATTERING; PRECISION-MEASUREMENT; ATOMIC CESIUM AB We find the leading-order result for the anapole form factor of the deuteron using effective field theory. The momentum dependence of the anapole form factor is different from that of the matrix element of the strange currents in the deuteron, which may provide a way for disentangling these two competing effects when analyzing parity-violating electron-deuteron scattering experiments. We give closed form expressions for both the form factor and integrals often encountered in the NN effective field theory. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Jefferson Lab, Newport News, VA 23606 USA. Univ Washington, Inst Nucl Theory, Seattle, WA 98195 USA. RP Savage, MJ (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. NR 82 TC 17 Z9 17 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 APR 9 PY 2001 VL 686 BP 413 EP 428 DI 10.1016/S0375-9474(00)00568-6 PG 16 WC Physics, Nuclear SC Physics GA 413TW UT WOS:000167628800022 ER PT J AU Milosevich, Z Vardaci, E DeYoung, PA Brown, CM Kaplan, M Whitfield, JP Peterson, D Dykstra, C Barton, M Karol, PJ McMahan, MA AF Milosevich, Z Vardaci, E DeYoung, PA Brown, CM Kaplan, M Whitfield, JP Peterson, D Dykstra, C Barton, M Karol, PJ McMahan, MA TI Small angle particle-particle correlation measurements in the reactions 280 MeV Ar-40+Al-27 and 670 MeV Mn-55+C-12 SO NUCLEAR PHYSICS A LA English DT Article ID COMPOSITE NUCLEI; EMISSION TIMES; COLLISIONS; FRAGMENTS; LIFETIME AB Small-angle particle-particle correlations were measured in the two matching reactions 280 MeV Ar-40 + Al-27 and 670 MeV Mn-55 + C-12. These two reactions were used to produce the composite nucleus, Ga-67*, at the same initial excitation energy of 127 MeV, but with different entrance channel angular momentum distributions. A simple trajectory model was used to compute the average emission times between various particle pairs, and comparisons with the data show that there is a significant difference in the deexcitation of the composite nucleus formed from the two reactions. Statistical model calculations were compared to the experimental observations with the added constraint that the model input parameters were consistent with those derived from observed charged-particle energy spectra and angular distributions, It was found that the calculated correlation functions were insensitive to the input spin distributions, but agreed fairly well with the data from the lower-spin system. The higher-spin reaction data were poorly reproduced by the calculations. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Carnegie Mellon Univ, Dept Chem, Pittsburgh, PA 15213 USA. Hope Coll, Dept Phys, Holland, MI 49423 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Kaplan, M (reprint author), Carnegie Mellon Univ, Dept Chem, 4400 5th Ave, Pittsburgh, PA 15213 USA. NR 17 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 APR 9 PY 2001 VL 686 BP 525 EP 536 DI 10.1016/S0375-9474(00)00569-8 PG 12 WC Physics, Nuclear SC Physics GA 413TW UT WOS:000167628800027 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Cassada, J 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, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gordon, A Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K 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, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, J Lancaster, M Lander, R Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Litvintsev, DO Lobban, O Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mikshina, M Mitselmakher, G 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 Nakaya, T Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T 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 Tamubrello, P Tartarelli, GF Tanaka, M Tannenbaum, B Taylor, W Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vicinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, MJ Watanabe, T Waters, D Watts, T Webb, R 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 Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Cassada, J 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, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gordon, A Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K 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, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, J Lancaster, M Lander, R Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Litvintsev, DO Lobban, O Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mikshina, M Mitselmakher, G 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 Nakaya, T Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T 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 Tamubrello, P Tartarelli, GF Tanaka, M Tannenbaum, B Taylor, W Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vicinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, MJ Watanabe, T Waters, D Watts, T Webb, R 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 Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI First measurement of the ratio B(t -> Wb)/B(t -> Wq) and associated limit on the Cabibbo-Kobayashi-Maskawa element vertical bar V-tb vertical bar SO PHYSICAL REVIEW LETTERS LA English DT Article ID PRODUCTION CROSS-SECTION; SILICON VERTEX DETECTOR; TOP-QUARK PRODUCTION; COLLIDER DETECTOR; (P)OVER-BAR-P COLLISIONS; P(P)OVER-BAR COLLISIONS; ROOT-S=1.8 TEV; FERMILAB; PHYSICS; SEARCH AB We present the first measurement of the ratio of branching fractions R equivalent to B(t --> Wb)/B(t --> Wq) from pa collisions at roots = 1.8 TeV. The data set corresponds to 109 pb(-1) of data recorded by the Collider Detector at Fermilab during the 1992-95 Tevatron run. We measure R = 0.94(-0.24)(+0.31)(stat + syst) or R > 0.61 (0.56) at 90% (95)% C.L., in agreement with the standard model predictions. This measurement yields a limit on the Cabibbo-Kobayashi-Maskawa quark mixing matrix element \V-tb\ under the assumption of three generations and unitarity. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 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. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Nazl Frascati Lab, 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. 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, Dept Chem, Suwon 440746, South Korea. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. MIT, Cambridge, MA 02139 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 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, Sezione 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 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 Affolder, T (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Lancaster, Mark/C-1693-2008; Nomerotski, Andrei/A-5169-2010; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; Gorelov, Igor/J-9010-2015; Prokoshin, Fedor/E-2795-2012 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Gorelov, Igor/0000-0001-5570-0133; Prokoshin, Fedor/0000-0001-6389-5399 NR 16 TC 34 Z9 34 U1 1 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 APR 9 PY 2001 VL 86 IS 15 BP 3233 EP 3238 DI 10.1103/PhysRevLett.86.3233 PG 6 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700005 PM 11327939 ER PT J AU Alavi-Harati, A Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barker, AR Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hamm, J Hanagaki, K Hidaka, S Hsiung, YB Jejer, V Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL Mikelsons, P Monnier, E Nakaya, T Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Shields, J Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Turner, SE Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED AF Alavi-Harati, A Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barker, AR Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hamm, J Hanagaki, K Hidaka, S Hsiung, YB Jejer, V Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL Mikelsons, P Monnier, E Nakaya, T Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Shields, J Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Turner, SE Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED CA KTeV Collaboration TI Measurement of the branching ratio and asymmetry of the decay Xi degrees -> Sigma degrees gamma SO PHYSICAL REVIEW LETTERS LA English DT Article ID RADIATIVE HYPERON DECAYS; PARAMETER AB We have studied the rare weak radiative hyperon decay Xi degrees --> Sigma degrees gamma in the KTeV experiment at Fermilab. We have identified 4045 signal events over a background of 804 events. The dominant Xi degrees --> Lambda pi degrees decay, which was used for normalization, is the only important background source. An analysis of the acceptance of both modes yields a branching ratio of B(Xi degrees --> Sigma degrees gamma) / B(Xi degrees --> Lambda pi degrees) = (3.34 +/- 0.05 +/- 0.09) X 10(-3). By analyzing the final state decay distributions, we have also determined that the Sigma degrees emission asymmetry parameter for this decay is alpha (Xi Sigma) = -0.63 +/- 0.09. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Colorado, Boulder, CO 80309 USA. Elmhurst Coll, Elmhurst, IL 60126 USA. Osaka Univ, Toyonaka, Osaka 5600043, Japan. Rice Univ, Houston, TX 77005 USA. Rutgers State Univ, Piscataway, NJ 08854 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. Univ Virginia, Inst Nucl & Particle Phys, Charlottesville, VA 22901 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Ramberg, EJ (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 12 TC 11 Z9 12 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 APR 9 PY 2001 VL 86 IS 15 BP 3239 EP 3243 DI 10.1103/PhysRevLett.86.3239 PG 5 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700006 PM 11327940 ER PT J AU Deb, PK Amos, K Karataglidis, S Chadwick, MB Madland, DG AF Deb, PK Amos, K Karataglidis, S Chadwick, MB Madland, DG TI Predicting total reaction cross sections for nucleon-nucleus scattering SO PHYSICAL REVIEW LETTERS LA English DT Article ID ENERGIES; PROTONS; TARGETS; PB-208; MODEL AB Nucleon total reaction and neutron total cross sections to 300 MeV for C-12 and Pb-208, and for 65 MeV scattering spanning the mass range, are predicted using coordinate space optical potentials formed by full folding of effective nucleon-nucleon interactions with realistic nuclear ground state densities. Good to excellent agreement is found with existing data. C1 Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia. NR 17 TC 33 Z9 33 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 APR 9 PY 2001 VL 86 IS 15 BP 3248 EP 3251 DI 10.1103/PhysRevLett.86.3248 PG 4 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700008 PM 11327942 ER PT J AU Shvets, G Fisch, NJ AF Shvets, G Fisch, NJ TI Parametric excitations of fast plasma waves by counterpropagating laser beams SO PHYSICAL REVIEW LETTERS LA English DT Article ID CURRENT DRIVE; AMPLIFICATION; ACCELERATION; PULSES AB Short- and long-wavelength plasma waves can become strongly coupled in the presence of two counterpropagating laser pump pulses detuned by twice the cold-plasma frequency omega (p). What makes this four-wave interaction important is that the growth rate of the plasma waves occurs much faster than in the more obvious copropagating geometry. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 14 TC 22 Z9 22 U1 1 U2 2 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 APR 9 PY 2001 VL 86 IS 15 BP 3328 EP 3331 DI 10.1103/PhysRevLett.86.3328 PG 4 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700028 PM 11327962 ER PT J AU Jhi, SH Louie, SG Cohen, ML Ihm, J AF Jhi, SH Louie, SG Cohen, ML Ihm, J TI Vacancy hardening and softening in transition metal carbides and nitrides SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELASTIC-CONSTANTS; ELECTRONIC-STRUCTURE; BAND-STRUCTURE; HARDNESS; TITANIUM; TINX AB The effects of vacancies on mechanical properties of the transition metal carbides and nitrides are studied using the ab initio pseudopotential approach. Calculated shear elastic stiffness and electronic structures show that the vacancy produces entirely different effects on the mechanical strength of groups IVb nitrides and Vb carbides. It is found that the occupation of shear-unstable metallic dd bonding states changes essentially in an opposite way for the carbides and nitrides in the presence of vacancies, resulting in different responses to sheer stress. Our study provides an atomistic understanding of the anomaly in hardness for these substoichiometric materials. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Seoul Natl Univ, Ctr Theoret Phys, Seoul 151742, South Korea. RP Jhi, SH (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 25 TC 145 Z9 147 U1 3 U2 23 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 APR 9 PY 2001 VL 86 IS 15 BP 3348 EP 3351 DI 10.1103/PhysRevLett.86.3348 PG 4 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700033 PM 11327967 ER PT J AU Chu, YS Lister, TE Cullen, WG You, H Nagy, Z AF Chu, YS Lister, TE Cullen, WG You, H Nagy, Z TI Commensurate water monolayer at the RuO2(110)/water interface SO PHYSICAL REVIEW LETTERS LA English DT Article ID X-RAY-REFLECTIVITY; ELECTROLYTE INTERFACE; RUTHENIUM DIOXIDE; IN-SITU; SURFACE; ADSORPTION; DIFFRACTION; BEHAVIOR; ICE AB We demonstrate the presence of two types of commensurate, registered water monolayers with different densities at the RuO2(110)/bulk-water (0.1 M NaOH solution) interface with off-specular, oxygen crystal truncation rods. At anodic potentials (close to oxygen evolution), the extraneous water layer and the surface hydroxide layer form a bilayer with O-H-O bond distances similar to that of ice X. At cathodic potentials, the water molecules converted from the bridging OH molecules form a low-density water layer. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Expt Facil Div, Argonne, IL 60439 USA. RP Chu, YS (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI You, Hoydoo/A-6201-2011 OI You, Hoydoo/0000-0003-2996-9483 NR 21 TC 77 Z9 77 U1 4 U2 30 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 9 PY 2001 VL 86 IS 15 BP 3364 EP 3367 DI 10.1103/PhysRevLett.86.3364 PG 4 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700037 PM 11327971 ER PT J AU Hill, S Harrison, N Mola, M Wosnitza, J AF Hill, S Harrison, N Mola, M Wosnitza, J TI Anisotropy of the superconducting order parameter in kappa-(BEDT-TTF)(2)Cu(NCS)(2) SO PHYSICAL REVIEW LETTERS LA English DT Article ID JOSEPHSON PLASMA RESONANCE; ELECTRODYNAMICS; STATE C1 Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Univ Karlsruhe, Inst Phys, D-76128 Karlsruhe, Germany. RP Hill, S (reprint author), Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. RI Hill, Stephen/J-5383-2014 OI Hill, Stephen/0000-0001-6742-3620 NR 11 TC 18 Z9 18 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 9 PY 2001 VL 86 IS 15 BP 3451 EP 3451 DI 10.1103/PhysRevLett.86.3451 PG 1 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700059 PM 11327993 ER PT J AU Shibauchi, T Matsuda, Y Gaifullin, MB Tamegai, T AF Shibauchi, T Matsuda, Y Gaifullin, MB Tamegai, T TI Comment on "Millimeter-wave magneto-optical determination of the anisotropy of the superconducting order parameter in the molecular superconductor kappa-(BEDT-TTF)(2)Cu(NCS)(2)" SO PHYSICAL REVIEW LETTERS LA English DT Article ID JOSEPHSON PLASMA RESONANCE; INTERLAYER PHASE COHERENCE; VORTEX STATE; MIXED-STATE; BI2SR2CACU2O8+DELTA; LAYERS C1 IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. Univ Calif Los Alamos Natl Lab, STC, MST, Los Alamos, NM 87545 USA. Univ Tokyo, Inst Solid State Phys, Kashiwa, Chiba 2778581, Japan. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 1138656, Japan. RP Shibauchi, T (reprint author), IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. RI Shibauchi, Takasada/B-9349-2008; Tamegai, Tsuyoshi /C-6656-2011; Gaifullin, Marat/G-4803-2015 OI Shibauchi, Takasada/0000-0001-5831-4924; NR 8 TC 15 Z9 15 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 APR 9 PY 2001 VL 86 IS 15 BP 3452 EP 3452 DI 10.1103/PhysRevLett.86.3452 PG 1 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700060 PM 11327994 ER PT J AU Schrama, JM Singleton, J AF Schrama, JM Singleton, J TI Comment on "Millimeter-wave magneto-optical determination of the anisotropy of the superconducting order parameter in the molecular superconductor kappa-(BEDT-TTF)(2)Cu(NCS)(2)" - Reply SO PHYSICAL REVIEW LETTERS LA English DT Article ID STATE C1 Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. RP Schrama, JM (reprint author), Univ Oxford, Clarendon Lab, Parks Rd, Oxford OX1 3PU, England. NR 18 TC 9 Z9 9 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 APR 9 PY 2001 VL 86 IS 15 BP 3453 EP 3454 DI 10.1103/PhysRevLett.86.3453 PG 2 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700061 ER PT J AU Schmalian, J Wolynes, PG AF Schmalian, J Wolynes, PG TI Comment on "Stripe glasses: self-generated randomness in a uniformly frustrated system" - Schmalian and Wolynes Reply SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92093 USA. RP Schmalian, J (reprint author), Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RI Schmalian, Joerg/H-2313-2011 NR 5 TC 7 Z9 7 U1 1 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 APR 9 PY 2001 VL 86 IS 15 BP 3456 EP 3456 DI 10.1103/PhysRevLett.86.3456 PG 1 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700063 ER PT J AU Guo, CL Rodriguez, G Hoffbauer, MA Taylor, AJ AF Guo, CL Rodriguez, G Hoffbauer, MA Taylor, AJ TI Ultrafast dynamics of electron thermalization in gold (vol 86, pg 1638, 2001) SO PHYSICAL REVIEW LETTERS LA English DT Correction C1 Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Adv Chem Diagnost & Instrumentat Grp, Los Alamos, NM 87545 USA. RP Guo, CL (reprint author), Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, POB 1663, Los Alamos, NM 87545 USA. RI Rodriguez, George/G-7571-2012 OI Rodriguez, George/0000-0002-6044-9462 NR 1 TC 2 Z9 2 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 9 PY 2001 VL 86 IS 15 BP 3457 EP 3457 DI 10.1103/PhysRevLett.86.3457 PG 1 WC Physics, Multidisciplinary SC Physics GA 421CZ UT WOS:000168045700064 ER PT J AU Hendrix, DA Jarzynski, C AF Hendrix, DA Jarzynski, C TI A "fast growth" method of computing free energy differences SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; NONEQUILIBRIUM MEASUREMENTS; TEMPERATURE; HYSTERESIS; EQUATION; ENTROPY; ERRORS; BOUNDS; SPACE AB Let DeltaF be the free energy difference between two equilibrium states of a system. An established method of numerically computing DeltaF involves a single, long "switching simulation," during which the system is driven reversibly from one state to the other (slow growth, or adiabatic switching). Here we study a method of obtaining the same result from numerous independent, irreversible simulations of a much shorter duration (fast growth). We illustrate the fast growth method, computing the excess chemical potential of a Lennard-Jones fluid as a test case, and we examine the performance of fast growth as a practical computational tool. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Hendrix, DA (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM dhendrix@socrates.berkeley.edu; chrisy@lanl.gov RI Jarzynski, Christopher/B-4490-2009 OI Jarzynski, Christopher/0000-0002-3464-2920 NR 38 TC 110 Z9 110 U1 1 U2 19 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 8 PY 2001 VL 114 IS 14 BP 5974 EP 5981 DI 10.1063/1.1353552 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 415WA UT WOS:000167745500002 ER PT J AU Saravanan, C Markovic, NM Head-Gordon, M Ross, PN AF Saravanan, C Markovic, NM Head-Gordon, M Ross, PN TI Stripping and bulk CO electro-oxidation at the Pt-electrode interface: Dynamic Monte Carlo simulations SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID INFRARED-SPECTROSCOPY; CARBON-MONOXIDE; ACID-SOLUTIONS; PT(111); ELECTROOXIDATION; PLATINUM; SURFACE; MODEL; DEPENDENCE; ADSORPTION AB We perform dynamic Monte Carlo simulations to understand the kinetics of CO oxidation on Pt surface. Our simulations are performed on a model for CO electro-oxidation, where oxygen-containing species (adsorbed OH) formed on the Pt surface reacts with adsorbed CO by a Langmuir-Hinshelwood mechanism to form CO2. A systematic study of the model parameters shows that we obtain better electrocatalytic activity by increasing the surface diffusion coefficient of CO (k(D)) or the rate of reaction between adsorbed CO and adsorbed OH. We also show that if the initial state of adsorbed CO is a closely packed structure, increasing the surface coverage can result in negative voltammetry peak shifts because of the formation of weakly adsorbed states of CO. We have also modeled bulk CO voltammetry by introducing a CO adsorption rate, k(4). We show that near-zero currents are obtained for the potentials (E) where the rate of OH adsorption, k(1)(E), is much smaller than k(4). We also note that k(D) plays no significant role in CO oxidation when k(D)<>k(4), whereas they vary significantly when k(4)congruent tok(1)(E). (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Saravanan, C (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 26 TC 25 Z9 26 U1 2 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 8 PY 2001 VL 114 IS 14 BP 6404 EP 6412 DI 10.1063/1.1355237 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 415WA UT WOS:000167745500049 ER PT J AU Cui, ST Cummings, PT Cochran, HD AF Cui, ST Cummings, PT Cochran, HD TI Effect of branches on the structure of narrowly confined alkane fluids: n-hexadecane and 2,6,11,15-tetramethylhexadecane SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; THIN-FILMS; PHASE-TRANSITIONS; SOLVATION FORCES; SIMPLE LIQUIDS; SHEAR; TIME; DECANE; LAYERS; MICA AB Using realistic molecular models and accurately calculating the state condition of the fluids of linear and branched alkanes confined between two strongly adsorbing solid surfaces, we obtained strikingly different structure for the two confined fluids. The structure of the n-hexadecane is solid-like with the molecules clearly forming a layered structure. Within each molecular layer, the molecules are packed predominantly parallel to each other. The structures of adjacent layers are correlated such that the main chain axes of the molecules pack into a local hexagonal array. In contrast, the structure of the branched alkane (2,6,11,15-tetramethylhexadecane) fluid remains liquid-like. Although exhibiting density oscillations normal to the confining surfaces, the structure of the confined fluid of the branched alkane is disordered and the molecules are not confined to a particular layer. The amplitude of the density oscillations is much smaller than for the n-hexadecane. The in-plane positional correlation shows isotropic structure characteristic of liquid, and the orientation of the molecules shows very little correlation. (C) 2001 American Institute of Physics. C1 Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. RP Cui, ST (reprint author), Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 30 TC 23 Z9 23 U1 0 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 8 PY 2001 VL 114 IS 14 BP 6464 EP 6471 DI 10.1063/1.1357200 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 415WA UT WOS:000167745500056 ER PT J AU van den Oetelaar, RJA Xu, L Ogletree, DF Salmeron, M Tang, H Gui, J AF van den Oetelaar, RJA Xu, L Ogletree, DF Salmeron, M Tang, H Gui, J TI Tribocharging phenomena in hard disk amorphous carbon coatings with and without perfluoropolyether lubricants SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID POLARIZATION FORCE MICROSCOPY; PERFLUOROPOLYALKYLETHER FILMS; THIN-FILMS; WATER; SURFACES; MICA; CONDENSATION; INTERFACE AB Scanning polarization force microscopy was used to study changes in surface potential (tribocharging) caused by the contact between a tungsten carbide tip and the amorphous carbon coating of a hard disk, both when bare and when covered with Zdol-TX lubricant. The surface potential change produced by tip contact decays with time at a rate that is strongly dependent on lubricant coverage and on the presence of oxygen and water vapor in the environment. Two different charging mechanisms are proposed. One involves chemical modification of the surface by removal of oxygen bound to the surface. This gives rise to a potential change that decays with time. Another mechanism involves trapping of charge in states within the energy gap of the insulating carbon film. The potential change due to this trapped charge does not decay over periods much greater than 1 h. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Seagate Technol, Adv Tribol Res Grp, Fremont, CA 94538 USA. RP Salmeron, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Ogletree, D Frank/D-9833-2016 OI Ogletree, D Frank/0000-0002-8159-0182 NR 19 TC 7 Z9 7 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 7 PY 2001 VL 89 IS 7 BP 3993 EP 3998 DI 10.1063/1.1351001 PG 6 WC Physics, Applied SC Physics GA 413KE UT WOS:000167610900073 ER PT J AU Mao, SS Mao, XL Greif, R Russo, RE AF Mao, SS Mao, XL Greif, R Russo, RE TI Influence of preformed shock wave on the development of picosecond laser ablation plasma SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Using picosecond time-resolved shadowgrams, we measured the development of an expanding air plasma during double picosecond pulse laser ablation of solids. Prior to the formation of the air plasma, a shock wave was established by the first laser pulse interaction with the solid target. The second picosecond laser pulse interacted with the shock wave and induced the air plasma at the interface between the shock wave front and the ambient air. After the end of the second picosecond ablation laser pulse, the temporal expansion of the air plasma was found to follow the relation r similar tot(2/5). Results from this air plasma suggest that the shock wave induced by the first laser pulse only absorbs approximately 5% of the energy of the second picosecond laser pulse. Nevertheless, the expansion of the air plasma towards the target results in an enlarged heat-affected zone at the target surface. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Russo, RE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 10 TC 17 Z9 17 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 7 PY 2001 VL 89 IS 7 BP 4096 EP 4098 DI 10.1063/1.1351870 PG 3 WC Physics, Applied SC Physics GA 413KE UT WOS:000167610900088 ER PT J AU Yang, P Rodriguez, MA Kotula, P Miera, BK Dimos, D AF Yang, P Rodriguez, MA Kotula, P Miera, BK Dimos, D TI Processing, microstructure, and electric properties of buried resistors in low-temperature co-fired ceramics SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID FILM CERMET RESISTORS; RESISTIVITY AB The electrical properties of ruthenium oxide based devitrifiable resistors embedded within low-temperature co-fired ceramics were investigated from -100 degreesC to 100 degreesC. Special attention was given to the processing conditions and their effects on resistance and temperature coefficient of resistance (TCR). Results indicate that within this temperature range the conductance for these buried resistors is limited by tunneling of charge carriers through the thin glass layer between ruthenium oxide particles. A modified version of the tunneling barrier model is proposed to account for the microstructure ripening observed during thermal processing. The model parameters determined from curve fitting show that charging energy (i.e., the energy required for a charge carrier to tunnel through the glass barrier) is strongly dependent on particle size and particle-particle separation between ruthenium oxide grains. Initial coarsening of ruthenium oxide grains was found to reduce the charging energy and lower the resistance. However, when extended ripening occurs, the increase in particle-particle separation increases the charging energy, reduces the tunneling probability and gives rise to a higher resistance. The tradeoff between these two effects results in an optimum microstructure with a minimum resistance and TCR. Furthermore, the TCR of these buried resistors has been shown to be governed by the magnitude of the charging energy. Model parameters determined by our analysis appear to provide quantitative physical interpretations to the microstructural changes in the resistor, which in turn, are controlled by the processing conditions. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Yang, P (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Kotula, Paul/A-7657-2011 OI Kotula, Paul/0000-0002-7521-2759 NR 16 TC 13 Z9 13 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 7 PY 2001 VL 89 IS 7 BP 4175 EP 4182 DI 10.1063/1.1353563 PG 8 WC Physics, Applied SC Physics GA 413KE UT WOS:000167610900100 ER PT J AU Checa, AG Rodriguez-Navarro, A AF Checa, AG Rodriguez-Navarro, A TI Geometrical and crystallographic constraints determine the self-organization of shell microstructures in Unionidae (Bivalvia : Mollusca) SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE biomineralization; bivalve shell; microstructure; nacre; composite prisms; self-organization ID CRYSTAL; BIOMINERALIZATION; NUCLEATION; GROWTH; MODEL AB Unionid shells are characterized by an outer aragonitic prismatic layer and an inner nacreous layer. The prisms of the outer shell layer are composed of single-crystal fibres radiating from spheruliths. During prism development, fibres progressively recline to the growth front. There is competition between prisms, leading to the selection of bigger, evenly sized prisms. A new model explains this competition process between prisms, using fibres as elementary units of competition. Scanning electron microscopy and X-ray texture analysis show that, during prism growth, fibres become progressively orientated with their three crystallographic axes aligned, which results from geometric constraints and space limitations. Interestingly transition to the nacreous layer does not occur until a high degree of orientation of fibres is attained. There is no selection of crystal orientation in the nacreous layer and, as a result, the preferential orientation of crystals deteriorates. Deterioration of crystal orientation is most probably due to accumulation of errors as the epitaxial growth is suppressed by thick or continuous organic coals on some nacre crystals. In conclusion, the microstructural arrangement of the unionid shell is, to a large extent, self-organized with the main constraints being crystallographic and geometrical laws. C1 Univ Granada, Dept Paleontol & Estrat, Granada, Spain. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Checa, AG (reprint author), Univ Granada, Dept Paleontol & Estrat, Granada, Spain. EM acheca@ugr.es NR 24 TC 34 Z9 36 U1 3 U2 17 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD APR 7 PY 2001 VL 268 IS 1468 BP 771 EP 778 PG 8 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 422DU UT WOS:000168103900014 PM 11321067 ER PT J AU Linderoth, NA Simon, MN Hainfeld, JF Sastry, S AF Linderoth, NA Simon, MN Hainfeld, JF Sastry, S TI Binding of antigenic peptide to the endoplasmic reticulum-resident protein gp96/GRP94 heat shock chaperone occurs in higher order complexes - Essential role of some aromatic amino acid residues in the peptide-binding site SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID CRYSTAL-STRUCTURES; SH2 DOMAIN; GP96 GRP94; HSP90; RECEPTOR; FAMILY; FORMS; DNA AB Vaccination with heat shock protein gp96-antigenic peptide complexes produces a powerful specific immune response against cancers and infectious diseases in some experimental animal models, and gp96-peptide complexes are now being tested in human clinical trials. gp96 appears to serve as a natural adjuvant for chaperoning antigenic peptides into the immune surveillance pathways. A fundamental issue that needs to be addressed is the mechanism of binding of antigenic peptide to gp96, Here, we show using scanning transmission electron microscopy that recombinant gp96 binds peptide in stable multimeric complexes, which may have biological significance. To open the possibility for genetically engineering gp96 for improved immunogenicity and to understand if molecular recognition plays a role in the binding of antigenic peptide, we mutagenized some specific aromatic amino acids in the presumed peptide-binding pocket. Replacement of Tyr-667 or Tyr-678 to Ala reduced affinity for peptide whereas conversion of Trp-654 to Tyr increased peptide binding. Similarly, changing Trp-621 to Phe or Leu or Ala or lie negatively affected peptide binding whereas changing Trp-621 to Tyr or Val positively affected peptide binding, Probing the peptide microenvironment in gp86-peptide complexes, suggested that hydrophobic interactions land perhaps hydrogen bonding/stacking interactions) may play a role in peptide loading by gp96. C1 Rockefeller Univ, Mol Genet Lab, New York, NY 10021 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Rockefeller Univ, Mol Genet Lab, 1230 York Ave, New York, NY 10021 USA. EM sastrys@rockvax.rockefeller.edu FU NCRR NIH HHS [P41-RR01777] NR 33 TC 18 Z9 19 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 EI 1083-351X J9 J BIOL CHEM JI J. Biol. Chem. PD APR 6 PY 2001 VL 276 IS 14 BP 11049 EP 11054 DI 10.1074/jbc.M010059200 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 420AC UT WOS:000167980900065 PM 11148208 ER PT J AU Eikerling, M Kornyshev, AA AF Eikerling, M Kornyshev, AA TI Proton transfer in a single pore of a polymer electrolyte membrane SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article DE polymer electrolyte membrane; proton transfer; activation energy ID CHARGE-TRANSFER; WATER; MODEL; LIQUID AB We discuss the principles determining the activation of proton hops in pores of polymer-electrolyte membranes and calculate the electrostatic contributions to the activation Gibbs energy. For this purpose, we explore a model of a flat water filled pore with charged sulfonic groups on the surfaces. We find that when the proton transport takes place along the array of sulfonic groups, the contribution of the work terms due to the proton charge interaction with sulfonic groups is large. In the central region of the pore, where the proton transport proceeds in a bulk-like fashion the work terms vanish. Moreover, the activation energy of the hopping along the surface increases considerably with the average distance between the sulfonic groups. Squeezing the pore leaves no room for bulk like proton transfer and, though the effect on the solvent reorganization energy may be small, the overall effective activation energy increases strongly. This is in line with the observed effect of decreasing water content on membrane conductivity. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Julich GmbH, Inst Mat & Proc Energy Syst, Res Ctr, D-52425 Julich, Germany. RP Eikerling, M (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Kornyshev, Alexei/C-3404-2008 NR 29 TC 93 Z9 100 U1 1 U2 15 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD APR 6 PY 2001 VL 502 IS 1-2 BP 1 EP 14 DI 10.1016/S0022-0728(00)00368-5 PG 14 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 435KD UT WOS:000168879900001 ER PT J AU Beernink, PT Segelke, BW Hadi, MZ Erzberger, JP Wilson, DM Rupp, B AF Beernink, PT Segelke, BW Hadi, MZ Erzberger, JP Wilson, DM Rupp, B TI Two divalent metal ions in the active site of a new crystal form of human apurinic/apyrimidinic endonuclease, Ape1: Implications for the catalytic mechanism SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE Ape1 endonuclease; base excision repair; enzyme mechanism; metalloenzyme; abasic DNA ID DNA-REPAIR ENZYME; DIRECTED MUTAGENESIS; MACROMOLECULAR STRUCTURES; ABASIC SITES; BINDING; REF-1; HAP1; RESIDUES; IDENTIFICATION; RESOLUTION AB The major human abasic endonuclease, Ape1, is an essential DNA repair enzyme that initiates the removal of apurinic/apyrimidinic sites from DNA, excises 3' replication-blocking moieties, and modulates the DNA binding activity of several transcriptional regulators. We have determined the X-ray structure of the full-length human Ape1 enzyme in two new crystal forms, one at neutral and one at acidic pH. The new structures are generally similar to the previously determined structure of a truncated Ape1 protein, but differ in the conformation of several loop regions and in spans of residues with weak electron density. While only one active-site metal ion is present in the structure determined at low pH, the structure determined from a crystal grown at the pH optimum of Ape1 nuclease activity, pH 7.5, has two metal ions bound 5 Angstrom apart in the active site. Enzyme kinetic data indicate that at least two metal-binding sites are functionally important, since Ca2+ exhibits complex stimulatory and inhibitory effects on the Mg2+-dependent catalysis of Ape1, even though Ca2+ itself does not serve as a cofactor. In conjunction, the structural and kinetic data suggest that Ape1 catalyzes hydrolysis of the DNA backbone through a two metal ion-mediated mechanism. (C) 2001 Academic Press. C1 Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Wilson, DM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. FU NCI NIH HHS [CA79056] NR 54 TC 115 Z9 124 U1 0 U2 4 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD APR 6 PY 2001 VL 307 IS 4 BP 1023 EP 1034 DI 10.1006/jmbi.2001.4529 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 419YN UT WOS:000167977300006 PM 11286553 ER PT J AU Schmidt, HJ Luban, M AF Schmidt, HJ Luban, M TI Continuous families of isospectral Heisenberg spin systems and the limits of inference from measurements SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article AB We investigate classes of quantum Heisenberg spin systems which have different coupling constants but the same energy spectrum and hence the same thermodynamical properties. To this end we define various types of isospectrality and establish conditions for their occurrence. The triangle and the tetrahedron whose vertices are occupied by spin 1/2 are investigated in some detail. The problem is also of practical interest since isospectrality presents an obstacle to the experimental determination of the coupling constants of small interacting spin systems such as magnetic molecules. C1 Univ Osnabruck, Fachbereich Phys, D-49069 Osnabruck, Germany. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Schmidt, HJ (reprint author), Univ Osnabruck, Fachbereich Phys, Barbarastr 7, D-49069 Osnabruck, Germany. NR 14 TC 13 Z9 13 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD APR 6 PY 2001 VL 34 IS 13 BP 2839 EP 2858 DI 10.1088/0305-4470/34/13/313 PG 20 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 422HK UT WOS:000168112300020 ER PT J AU Peterson, BJ Wollheim, WM Mulholland, PJ Webster, JR Meyer, JL Tank, JL Marti, E Bowden, WB Valett, HM Hershey, AE McDowell, WH Dodds, WK Hamilton, SK Gregory, S Morrall, DD AF Peterson, BJ Wollheim, WM Mulholland, PJ Webster, JR Meyer, JL Tank, JL Marti, E Bowden, WB Valett, HM Hershey, AE McDowell, WH Dodds, WK Hamilton, SK Gregory, S Morrall, DD TI Control of nitrogen export from watersheds by headwater streams SO SCIENCE LA English DT Article ID INORGANIC NITROGEN; FOREST STREAM; AMMONIUM; SIZE; ECOSYSTEMS; PHOSPHORUS; SATURATION; RETENTION; STORAGE; CHANNEL AB A comparative N-15-tracer study of nitrogen dynamics in headwater streams from biomes throughout North America demonstrates that streams exert control over nutrient exports to rivers, Lakes, and estuaries. The most rapid uptake and transformation of inorganic nitrogen occurred in the smallest streams. Ammonium entering these streams was removed from the water within a few tens to hundreds of meters. Nitrate was also removed from stream water but traveled a distance 5 to 10 times as long, on average, as ammonium. Despite low ammonium concentration in stream water, nitrification rates were high, indicating that small streams are potentially important sources of atmospheric nitrous oxide. During seasons of high biological activity, the reaches of headwater streams typically export downstream Less than half of the input of dissolved inorganic nitrogen from their watersheds. C1 Marine Biol Lab, Ctr Ecosyst, Woods Hole, MA 02543 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Virginia Polytech Inst & State Univ, Dept Biol, Blacksburg, VA 24061 USA. Univ Georgia, Inst Ecol, Athens, GA 30602 USA. Univ Illinois, Dept Nat Resources & Environm Sci, Urbana, IL 61801 USA. Ctr Estudis Avancats Blanes, Blanes 17300, Girona, Spain. Landcare Res, Lincoln 8152, New Zealand. Univ N Carolina, Dept Biol, Greensboro, NC 27402 USA. Univ New Hampshire, Dept Nat Resources, Durham, NH 03824 USA. Kansas State Univ, Div Biol, Manhattan, KS 66506 USA. Michigan State Univ, Kellogg Biol Stn, Hickory Corners, MI 49060 USA. Oregon State Univ, Dept Fisheries & Wildlife, Corvallis, OR 97331 USA. Procter & Gamble Co, Expt Stream Facil, Milford, OH 45150 USA. RP Peterson, BJ (reprint author), Marine Biol Lab, Ctr Ecosyst, Woods Hole, MA 02543 USA. RI McDowell, William/E-9767-2010; Mulholland, Patrick/C-3142-2012; Marti, Eugenia/J-9146-2012; Bowden, William/J-9219-2014 OI McDowell, William/0000-0002-8739-9047; Marti, Eugenia/0000-0002-6910-4874; NR 28 TC 742 Z9 800 U1 28 U2 305 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 APR 6 PY 2001 VL 292 IS 5514 BP 86 EP 90 DI 10.1126/science.1056874 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 420FU UT WOS:000167995200042 PM 11292868 ER PT J AU Miller, WH AF Miller, WH TI The semiclassical initial value representation: A potentially practical way for adding quantum effects to classical molecular dynamics simulations SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Review ID TIME-CORRELATION FUNCTIONS; THERMAL RATE CONSTANTS; ELECTRONICALLY NONADIABATIC DYNAMICS; CUMULATIVE REACTION PROBABILITIES; INTRAMOLECULAR PROTON-TRANSFER; TRANSITION-STATE THEORY; HERMAN-KLUK PROPAGATOR; LOG-DERIVATIVE METHOD; MONTE-CARLO METHODS; S-MATRIX AB The semiclassical (SC) initial value representation (IVR) provides a potentially practical way for adding quantum mechanical effects to classical molecular dynamics (MD) simulations of the dynamics of complex molecular systems (i.e., those with many degrees of freedom). It does this by replacing the nonlinear boundary value problem of semiclassical theory by an average over the initial conditions of classical trajectories. This paper reviews the background and rebirth of interest in such approaches and surveys a variety of their recent applications. Special focus is on the ability to treat the dynamics of complex systems, and in this regard, the forward-backward (FB) version of the approach is especially promising. Several examples of the FB-IVR applied to model problems of many degrees of freedom show it to be capable of describing quantum effects quite well and also how these effects are quenched when some of the degrees of freedom are averaged over ("decoherence"). C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Kenneth S Pitzer Ctr Theoret Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Miller, WH (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 121 TC 456 Z9 458 U1 10 U2 74 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 APR 5 PY 2001 VL 105 IS 13 BP 2942 EP 2955 DI 10.1021/jp003712k PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 419AV UT WOS:000167927900005 ER PT J AU DeSain, JD Clifford, EP Taatjes, CA AF DeSain, JD Clifford, EP Taatjes, CA TI Infrared frequency-modulation probing of product formation in alkyl plus O-2 reactions: II. The reaction of C3H7 with O-2 between 296 and 683 K SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID PRESSURE-DEPENDENCE; PEROXY-RADICALS; VIBRATIONAL-RELAXATION; C2H5+O-2 REACTION; REACTION-KINETICS; MOLECULAR-OXYGEN; ETHYL RADICALS; RATE CONSTANTS; SELF-REACTION; C2H4 YIELD AB The production of HO2 from the reaction of C3H7 and O-2 has been investigated as a function of temperature (296-683 K) using laser photolysis/CW infrared frequency-modulation spectroscopy. The HO2 yield is derived by comparison with the Cl-2/CH3OH/O-2 system and is corrected to account for HO2 Signal loss due to competing reactions involving HO2 radical and the adduct C3H7O2 The time behavior of the HO2 signal following propyl radical formation was observed to have two separate components. The first component is a prompt production of HO2, which increases with temperature and is the only HO2 production observed between 296 and 550 K. This prompt yield increases from less than 1% at 296 K to similar to 16% at 683 K. At temperatures above 550 K, a second, slower rise in the HO2 signal is also observed. The production of HO2 on a slower time scale is attributable to propylperoxy radical decomposition. The total HO2 yield, including the contribution from the slower rise, increases rapidly with temperature from 5% at 500 K to 100% at 683 K. The second slower rise accounts for nearly all of the product formation at these higher temperatures. The biexponential time behavior of the HO2 production from C3H7 + O-2 is similar to that previously observed in studies of the C2H5 + O-2 reaction. The temperature dependence of the prompt yield for the two reactions is very similar, with the C3H7 + O-2 reaction having a slightly lower yield at each temperature. The temperature dependence of the total HO2 yield is also very similar for the two reactions, with the sharp increase in the total HO2 yield at high temperatures occurring in very similar temperature ranges. The phenomenological rate constant for delayed HO2 production from C3H7 + O-2 is Slightly larger than that for C2H5 + O-2 at each temperature. Apparent activation energies, obtained from an Arrhenius plot of the inverse of the time Constants for delayed HO2 production are similar for the two systems, being 24.6 and 26.0 kcal mol(-1) for C2H5 + O-2 and C3H7 + O-2 respectively. These results suggest similar coupled mechanisms for HO2 production in the C2H5 + O-2 and C3H7 + O-2 reactions, with similar concerted HO2 elimination pathways from the RO2 species. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Taatjes, CA (reprint author), Sandia Natl Labs, Combust Res Facil, Mail Stop 9055, Livermore, CA 94551 USA. NR 43 TC 42 Z9 42 U1 0 U2 8 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 APR 5 PY 2001 VL 105 IS 13 BP 3205 EP 3213 DI 10.1021/jp0036543 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 419AV UT WOS:000167927900037 ER PT J AU Wu, K Iedema, MJ Schenter, GK Cowin, JP AF Wu, K Iedema, MJ Schenter, GK Cowin, JP TI Sculpting the oil-water interface to probe ion solvation SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SOFT-LANDED IONS; LIQUID-LIQUID INTERFACES; MOLECULAR-DYNAMICS; SUPERCRITICAL CO2; GLASS-TRANSITION; VAPOR; SIMULATION; TRANSPORT; PT(111); FILMS AB Solvation of ions at oil-water interfaces is so important in cell wall and enzyme function, colloidal chemistry, fuel cells, and other areas that substantial effort has been made to understand the process via molecular-scale simulations of well-specified model systems. Here we report a series of experiments probing ion transport and solvation in composite films that have a geometrical specificity that rivals what theory is routinely able to employ. Proton/hydronium transport across the water-organic interface has been studied using a novel "soft-landed" ion technique that allows precision tailoring of the interfaces (including initial ion position) and sensitive monitoring of the ion motion via the electric potential generated by the ions. There are two main findings. First, the ion solvation by water at the organic-aqueous interface is probed continuously for various monolayers of water present in simple and complex sandwiched structures. The potential trap created by the solvation can be systematically overwhelmed by the collective electric field of the ions, giving us some unique information about both the trap depth and shape. A simple Born model for the trap reproduces some, but not all, of the details experimentally observed. Second, ion transport in several organic glasses is well-predictable by continuum viscosity models at electric fields up to approximately 10(8) V/m. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Cowin, JP (reprint author), Pacific NW Natl Lab, Box 999,MS K8-88, Richland, WA 99352 USA. RI Schenter, Gregory/I-7655-2014; Wu, Kai/A-4903-2011 OI Schenter, Gregory/0000-0001-5444-5484; Wu, Kai/0000-0002-5016-0251 NR 66 TC 8 Z9 8 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 5 PY 2001 VL 105 IS 13 BP 2483 EP 2498 DI 10.1021/jp003053b PG 16 WC Chemistry, Physical SC Chemistry GA 419AW UT WOS:000167928000003 ER PT J AU Ciraolo, MF Hanson, JC Norby, P Grey, CP AF Ciraolo, MF Hanson, JC Norby, P Grey, CP TI An in-situ X-ray powder diffraction study of the adsorption of hydrofluorocarbons in zeolites SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID NMR; NAY AB A time resolved in-situ synchrotron X-ray powder diffraction study of hydrofluorocarbon (HFC)-134 (CF2HCF2H) and -134a (CF3CFH2) adsorption on NaY has been performed, as a function of the temperature of the zeolite molecular sieve. Use of an image plate, allowed kinetic processes to be followed with a resolution of the order of a few seconds. The 111 reflection of the zeolite framework is very intense and particularly sensitive to adsorption of gases, whereas the weaker 220 reflection is fairly insensitive to gas sorption. The adsorption process could, therefore, be readily monitored by using a ratio of the integrated intensities of these two reflections. This ratio was found to be an accurate measure of gas loading level and loading levels could be estimated from this ratio by using a calibration curve established with samples loaded es-situ. Furthermore, good agreement was found between the experimentally measured value of this ratio, and that obtained by calculating the 111 and 220 structure factors from our earlier structural model for the HFC-134 bound to NaY (Grey, C. P.; Poshni, F. I.; Gualtieri, A. F.; Norby, P.; Hanson, J. C.; Corbin, D. R. J. Am. Chern. Sec. 1997, 119, 1981). A contraction of the unit cell parameter was observed that correlated with the HFC loading level. This contraction occurred abruptly at room temperature but was both smoother and slower at higher temperatures (100 degreesC). The kinetics of sorption depended strongly on temperature, lower temperatures reaching equilibrium more rapidly. This result was explained by an increase in the interparticle diffusion rate at higher temperatures, so that equilibrium is not reached until all the zeolite particles in the whole capillary tube are uniformly loaded with HFC molecules. At low temperatures, the HFC molecules are strongly bound to the crystallite particles so that the adsorption front fills the particles sequentially, moving steadily and rapidly through the sample. C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Univ Oslo, Dept Chem, N-0315 Oslo, Norway. RP Grey, CP (reprint author), SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RI Hanson, jonathan/E-3517-2010; Norby, Poul/B-9047-2014 OI Norby, Poul/0000-0002-2590-7050 NR 21 TC 10 Z9 10 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 5 PY 2001 VL 105 IS 13 BP 2604 EP 2611 DI 10.1021/jp004232w PG 8 WC Chemistry, Physical SC Chemistry GA 419AW UT WOS:000167928000019 ER PT J AU Seshadri, K Wilder, JW Smith, DH AF Seshadri, K Wilder, JW Smith, DH TI Measurements of equilibrium pressures and temperatures for propane hydrate in silica gels with different pore-size distributions SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID THERMODYNAMIC PROPERTIES; HEAT-CAPACITIES; DISSOCIATION; METHANE; ENTHALPIES; 270-K AB Equilibrium pressures for the dissociation of propane hydrate confined in silica gel pores of nominal radii 7.5, 5.0, 3.0, and, 2.0 nm were measured across a wide temperature range, and were higher than those for bulk propane hydrate. The upward shift from the bulk pressures, which depended on the pore size, was 200-300% for the smallest pore size. In each of the pressure-temperature profiles, the temperature at which the four phases (hydrate, ice, liquid water, and gas) apparently coexisted was identified, and this temperature was a linear function of the reciprocal pore size. The enthalpy of dissociation for the equilibrium involving hydrate, liquid water, and gas was estimated from the data. The change with pore size in this apparent enthalpy appeared to be analogous to the variation in the heat of melting of pore ice as sometimes reported. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. Parsons Infrastruct & Technol Grp, Morgantown, WV 26505 USA. W Virginia Univ, Dept Math, Morgantown, WV 26506 USA. RP Smith, DH (reprint author), US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. NR 20 TC 60 Z9 64 U1 2 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 APR 5 PY 2001 VL 105 IS 13 BP 2627 EP 2631 DI 10.1021/jp0040244 PG 5 WC Chemistry, Physical SC Chemistry GA 419AW UT WOS:000167928000022 ER PT J AU Van Keuls, FW Chevalier, CT Miranda, FA Carlson, CM Rivkin, TV Parilla, PA Perkins, JD Ginley, DS AF Van Keuls, FW Chevalier, CT Miranda, FA Carlson, CM Rivkin, TV Parilla, PA Perkins, JD Ginley, DS TI Comparison of the experimental performance of ferroelectric CPW circuits with method-of-moment simulations and conformal mapping analysis SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE thin-film ferroelectric; coplanar waveguide; phase shifter ID THIN-FILMS; PHASE SHIFTERS; MICROWAVE PERMITTIVITY; BAND; CAPACITORS; FREQUENCY; GHZ AB Experimental measurements of coplanar waveguide circuits atop thin films of ferroelectric BaxSr1-xTiO3 (BST) were made as a function of dc bias from 0 to 200 V and frequency from 0.045 to 20 GHz. The resulting phase shifts are compared with method-of-moments electromagnetic simulations and a conformal mapping analysis to determine the dielectric constant of the BST films. The accuracy of the resulting dielectric constants is analyzed and compared to low-frequency measurements of interdigitated capacitor circuits on the same films. (C) 2001 John Wiley & Sons, Inc. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Micron Technol Inc, Boise, ID 83707 USA. NREL, Golden, CO 80401 USA. RP Van Keuls, FW (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 13 TC 5 Z9 5 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0895-2477 J9 MICROW OPT TECHN LET JI Microw. Opt. Technol. Lett. PD APR 5 PY 2001 VL 29 IS 1 BP 34 EP 37 DI 10.1002/mop.1074 PG 4 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA 409YA UT WOS:000167412200010 ER PT J AU Dosa, PI Schleifenbaum, A Vollhardt, KPC AF Dosa, PI Schleifenbaum, A Vollhardt, KPC TI Isomerization of linear to angular [3]phenylene and PAHs under flash vacuum pyrolysis conditions SO ORGANIC LETTERS LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; HIGH-TEMPERATURE BEHAVIOR; ALKYNES; DERIVATIVES; THERMOLYSIS; GENERATION; ARYL AB Flash vacuum pyrolysis (FVP) of linear [S]phenylene affords its angular counterpart and the same mixture of polycyclic aromatic hydrocarbon isomers as that observed on RIP of angular [3]phenylene, A mechanism, supported by a C-13 labeling study, is proposed to explain these results. C1 Univ Calif Berkeley, Dept Chem, Ctr New direct Organ Synth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Vollhardt, KPC (reprint author), Univ Calif Berkeley, Dept Chem, Ctr New direct Organ Synth, Berkeley, CA 94720 USA. NR 24 TC 21 Z9 21 U1 3 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1523-7060 J9 ORG LETT JI Org. Lett. PD APR 5 PY 2001 VL 3 IS 7 BP 1017 EP 1020 DI 10.1021/ol015519u PG 4 WC Chemistry, Organic SC Chemistry GA 419BG UT WOS:000167929000015 PM 11277784 ER PT J AU Goity, JL Lehmann, D Prezeau, G Saez, J AF Goity, JL Lehmann, D Prezeau, G Saez, J TI Regularization for effective field theory with two heavy particles SO PHYSICS LETTERS B LA English DT Article DE regularization; effective field theory; Baryon chiral perturbation theory; NN effective field theory; low-energy power counting ID CHIRAL PERTURBATION-THEORY; LAGRANGIANS; NUCLEONS; QUARKS AB A regularization for effective field theory with two propagating heavy particles is constructed. This regularization preserves the low-energy analytic structure, implements a low-energy power counting for the one-loop diagrams, and preserves symmetries respected by dimensional regularization. (C) 2001 Published by Elsevier Science B.V. C1 Hampton Univ, Dept Phys, Hampton, VA 23668 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Goity, JL (reprint author), Hampton Univ, Dept Phys, Hampton, VA 23668 USA. NR 15 TC 19 Z9 19 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 5 PY 2001 VL 504 IS 1-2 BP 21 EP 27 DI 10.1016/S0370-2693(01)00289-1 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 418GD UT WOS:000167881800004 ER PT J AU Zhang, ZT Dai, S Hunt, RD Wei, Y Qiu, SL AF Zhang, ZT Dai, S Hunt, RD Wei, Y Qiu, SL TI Ion-imprinted zeolite: A surface functionalization methodology based on the "ship-in-bottle" technique SO ADVANCED MATERIALS LA English DT Article ID MOLECULAR-SIEVES OFMSS; MESOPOROUS CHANNELS; POLYMERS; COMPLEXES; EXCHANGE; HYDROGENATION; ADSORPTION; CATALYSIS; TEMPLATES; SORBENTS AB A new methodology to effectively modify the selectivity of zeolites toward a target metal ion via surface molecular imprinting has been developed. A stepwise methodology in which the template complex is assembled inside the zeolite pore in a piece-by-piece fashion is shown (see Figure). Tailored zeolites with surface functionalization show great promise for the realization of shape-selective catalysis. [GRAPHICS] C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Drexel Univ, Dept Chem, Philadelphia, PA 19104 USA. Jilin Univ, Dept Chem, Jilin, Peoples R China. RP Dai, S (reprint author), Oak Ridge Natl Lab, Div Chem Technol, POB 2008, Oak Ridge, TN 37831 USA. RI Wei, Yen/H-5329-2012; Dai, Sheng/K-8411-2015 OI Dai, Sheng/0000-0002-8046-3931 NR 29 TC 28 Z9 28 U1 0 U2 25 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0935-9648 J9 ADV MATER JI Adv. Mater. PD APR 4 PY 2001 VL 13 IS 7 BP 493 EP + DI 10.1002/1521-4095(200104)13:7<493::AID-ADMA493>3.0.CO;2-X PG 5 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 421ZL UT WOS:000168093400007 ER PT J AU Wu, YY Yang, PD AF Wu, YY Yang, PD TI Direct observation of vapor-liquid-solid nanowire growth SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID SEMICONDUCTOR NANOWIRES; SILICON NANOWIRES; CARBON NANOTUBES; LASER-ABLATION C1 Univ Calif Berkeley, Dept Chem, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Yang, PD (reprint author), Univ Calif Berkeley, Dept Chem, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Wu, Yiying/A-3949-2011; OI Wu, Yiying/0000-0001-9359-1863 NR 24 TC 734 Z9 750 U1 27 U2 239 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 APR 4 PY 2001 VL 123 IS 13 BP 3165 EP 3166 DI 10.1021/ja0059084 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 416XT UT WOS:000167806300038 ER PT J AU Sagi, J Guliaev, AB Singer, B AF Sagi, J Guliaev, AB Singer, B TI 15-mer DNA duplexes containing an abasic site are thermodynamically more stable with adjacent purines than with pyrimidines SO BIOCHEMISTRY LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; REFINED SOLUTION STRUCTURE; DEOXYADENOSINE STACKS; SOLUTION CONFORMATION; MOLECULAR MECHANICS; APYRIMIDINIC SITES; THERMAL-STABILITY; HELIX OPPOSITE; SEQUENCE; FLEXIBILITY AB Abasic site (AP)-containing duplexes, with flanking adenine (A) or cytosine (C) bases, were shown to be more stable with flanking A than with C bases [Sagi, J., Hang, B., and Singer, B. (1999) Chem. Res. Toxicol. 12, 917-923]. We investigated whether the lower-magnitude destabilization by an AP site, with A neighbors, is a general effect of the purine versus the pyrimidine neighbors. Duplex stability, as compared to that of the corresponding control duplexes, was markedly decreased by the incorporation of the AP site (x) opposite any of the four bases. However, for the duplexes containing T, A, or C opposite the AP site, replacement of the symmetric doublet flanking pyrimidine bases with purines resulted in a smaller destabilization effect. The average stabilizing effect of the symmetric doublet purine neighbors of an AP site opposite T, A, or C bases was 3.2 degreesC (DeltaT(m)) and 1.3 kcal/mol (Delta DeltaG degrees (37)) compared to those of pyrimidine neighbors. In contrast, a G.AP pair reduced or eliminated the differential effect of the neighbors. Using unrestrained molecular dynamics, it was shown that for the duplexes containing T opposite the AP site, with doublet pyrimidine neighbors, there was a larger magnitude of curvature around the lesion site than for the duplexes with the purines flanking the AP site. Purines flanking the AP site tend to shift toward each other, creating overlap, in contrast to the flanking pyrimidines. This indicates the possibility of stacking between purine bases at the AP site and can be the reason for the observed smaller thermodynamic destabilization of the duplexes with the AAxAA and GGxGG central sequences, as compared to those with TTxTT and CCxCC sequences. This work showed that for an AP site the GC content is not the only determinant of duplex stability, but rather is influenced more by whether purines or pyrimidines flank the AP site. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Donner Lab, Berkeley, CA 94720 USA. RP Singer, B (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Donner Lab, Berkeley, CA 94720 USA. FU NCI NIH HHS [CA 72079, CA 47723] NR 40 TC 20 Z9 20 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD APR 3 PY 2001 VL 40 IS 13 BP 3859 EP 3868 DI 10.1021/bi0024409 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 416UM UT WOS:000167798600011 PM 11300765 ER PT J AU Sharp, JA Fouts, ET Krawitz, DC Kaufman, PD AF Sharp, JA Fouts, ET Krawitz, DC Kaufman, PD TI Yeast histone deposition protein Asf1p requires Hir proteins and PCNA for heterochromatic silencing SO CURRENT BIOLOGY LA English DT Article ID ASSEMBLY FACTOR-I; DNA-REPLICATION INVITRO; SACCHAROMYCES-CEREVISIAE; ALTER TRANSCRIPTION; MATING LOCI; CHROMATIN; MUTATIONS; GENE; REPRESSION; INHERITANCE AB Background: Position-dependent gene silencing in yeast involves many factors, including the four HIR genes and nucleosome assembly proteins Asf1p and chromatin assembly factor I (CAF-I, encoded by the CAC1-3 genes), Both cac Delta asf1 Delta and cac Delta hir Delta double mutants display synergistic reductions in heterochromatic gene silencing, However, the relationship between the contributions of HIR genes and ASF1 to silencing has not previously been explored. Results: Our biochemical and genetic studies of yeast Asf1p revealed links to Hir protein function, In vitro, an active histone deposition complex was formed from recombinant yeast Asf1p and histones H3 and H4 that lack a newly synthesized acetylation pattern. This Asf1p/H3/H4 complex generated micrococcal nuclease-resistant DNA in the absence of DNA replication and stimulated nucleosome assembly activity by recombinant yeast CAF-I during DNA synthesis. Also, Asf1p bound to the Hir1p and Hir2p proteins in vitro and in cell extracts, In vivo, the HIR1 and ASF1 genes contributed to silencing the heterochromatic HML locus via the same genetic pathway. Deletion of either HIR1 or ASF1 eliminated telomeric gene silencing in combination with pol30-8, encoding an altered form of the DNA polymerase processivity factor PCNA that prevents OAF-I from contributing to silencing, Conversely, other pol30 alleles prevented Asf1/Hir proteins from contributing to silencing. Conclusions: Yeast CAP-I and Asf1p cooperate to form nucleosomes in vitro. In vivo, Asf1p and Hir proteins physically interact and together promote heterochromatic gene silencing in a manner requiring PCNA. This Asf1/Hir silencing pathway functionally overlaps with CAP-I activity. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. RP Kaufman, PD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [1 RO1 GM55712] NR 56 TC 193 Z9 199 U1 0 U2 3 PU CELL PRESS PI CAMBRIDGE PA 1100 MASSACHUSETTES AVE,, CAMBRIDGE, MA 02138 USA SN 0960-9822 J9 CURR BIOL JI Curr. Biol. PD APR 3 PY 2001 VL 11 IS 7 BP 463 EP 473 DI 10.1016/S0960-9822(01)00140-3 PG 11 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 438WF UT WOS:000169076700015 PM 11412995 ER PT J AU Kuznetsova, A Yates, JT Zhou, G Yang, JC Chen, XD AF Kuznetsova, A Yates, JT Zhou, G Yang, JC Chen, XD TI Making a superior oxide corrosion passivation layer on aluminum using ozone SO LANGMUIR LA English DT Article ID ELECTRON-IMPACT; OXIDATION; AL(111) AB Aluminum oxidation by ozone produces an aluminum oxide layer which is superior in its corrosion properties compared to natural oxide, as measured by electrochemical methods. The electrochemically measured impedance of the O-3-grown films is similar to 10 times greater than that of O-2-grown films of equivalent thickness. An enhanced pitting potential is observed for the O-3-grown oxide film. Transmission electron microscopy results show that the pore size of O-3-grown oxide films is considerably smaller than that of O-2-grown films. Transmission electron microscopy electron diffraction studies show that the amorphous O-3-grown films are similar to 4% more dense than the O-2-grown film. The initial sticking coefficient for ozone on atomically clean polycrystalline aluminum is 3.8 times larger than for oxygen at 300 K C1 Univ Pittsburgh, Dept Chem, Ctr Surface Sci, Pittsburgh, PA 15260 USA. Univ Pittsburgh, Dept Mat Sci & Engn, Pittsburgh, PA 15261 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Yates, JT (reprint author), Univ Pittsburgh, Dept Chem, Ctr Surface Sci, Pittsburgh, PA 15260 USA. NR 14 TC 25 Z9 25 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 APR 3 PY 2001 VL 17 IS 7 BP 2146 EP 2152 DI 10.1021/la001300x PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 416CP UT WOS:000167762700016 ER PT J AU Cabrillo, C Bermejo, FJ Gibson, JM Johnson, JA Faccio, D Pruneri, V Kazansky, PG AF Cabrillo, C Bermejo, FJ Gibson, JM Johnson, JA Faccio, D Pruneri, V Kazansky, PG TI Thermally poled silica samples are structurally heterogeneous: Electron diffraction evidence of partial crystallization SO APPLIED PHYSICS LETTERS LA English DT Article ID 2ND-HARMONIC GENERATION; OPTICAL NONLINEARITY; MOLECULAR-DYNAMICS; GEO2-SIO2 GLASS; CRISTOBALITE; FIELD; SIO2 AB Large structural modifications in v-SiO2 are found to be induced by "thermal poling," a treatment which makes the glass act as a frequency doubler of an impinging infrared light. The electron diffraction patterns of poled silica plates reveal the presence of a large amount (of order 10%) of crystallites showing patterns consistent with partial crystallization of the glassy matrix into the cristobalite polymorph of silica. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Argonne, IL 60439 USA. CSIC, E-28006 Madrid, Spain. Univ Southampton, Optoelect Res Ctr, Southampton SO17 1BJ, Hants, England. RP Johnson, JA (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Gibson, Murray/E-5855-2013; Johnson, Jacqueline/P-4844-2014 OI Gibson, Murray/0000-0002-0807-6224; Johnson, Jacqueline/0000-0003-0830-9275 NR 14 TC 19 Z9 19 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 2 PY 2001 VL 78 IS 14 BP 1991 EP 1993 DI 10.1063/1.1359776 PG 3 WC Physics, Applied SC Physics GA 415VT UT WOS:000167744800011 ER PT J AU Verebelyi, DT Cantoni, C Budai, JD Christen, DK Kim, HJ Thompson, JR AF Verebelyi, DT Cantoni, C Budai, JD Christen, DK Kim, HJ Thompson, JR TI Critical current density of YBa2Cu3O7-delta low-angle grain boundaries in self-field SO APPLIED PHYSICS LETTERS LA English DT Article ID SUPERCONDUCTING TAPES; THICK-FILMS AB A study has been perfomed on the superconducting critical current density J(c) flowing across low-angle grain boundaries in epitaxial thin films of YBa2Cu3O7-delta. The materials studied were dual grain boundary rings deposited on SrTiO3 and containing 2 degrees, 3 degrees, 5 degrees, and 7 degrees tilt boundaries. The current density in self-field was determined by magnetometric methods at temperatures from 5 K to T-c. We conclude that at the higher temperatures of coated conductor applications, there is limited potential for improving J(c) by reducing the grain boundary angle below similar to3 degrees. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Verebelyi, DT (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Budai, John/R-9276-2016; Cantoni, Claudia/G-3031-2013 OI Budai, John/0000-0002-7444-1306; Cantoni, Claudia/0000-0002-9731-2021 NR 11 TC 32 Z9 32 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 2 PY 2001 VL 78 IS 14 BP 2031 EP 2033 DI 10.1063/1.1360230 PG 3 WC Physics, Applied SC Physics GA 415VT UT WOS:000167744800025 ER PT J AU Lin, A Hong, X Wood, V Verevkin, AA Ahn, CH McKee, RA Walker, FJ Specht, ED AF Lin, A Hong, X Wood, V Verevkin, AA Ahn, CH McKee, RA Walker, FJ Specht, ED TI Epitaxial growth of Pb(Zr0.2Ti0.8)O-3 on Si and its nanoscale piezoelectric properties SO APPLIED PHYSICS LETTERS LA English DT Article ID FORCE MICROSCOPY; THIN-FILMS; HETEROSTRUCTURES; SENSORS; SILICON; DOMAINS AB We have demonstrated a route to epitaxial Pb(Zr0.2Ti0.8)O-3 on (001) Si that exhibits a uniform piezoelectric response down to nanoscale levels through the utilization of an insulating, single-crystalline SrTiO3 transition layer. These structures, which were grown by a combination of molecular-beam epitaxy and off-axis magnetron sputtering, have a surface roughness of <5 Angstrom, with piezoelectric microscopy measurements revealing a piezoelectric coefficient of similar to 50 pm/V that is switchable down to sub-100-nm dimensions. (C) 2001 American Institute of Physics. C1 Yale Univ, Dept Appl Phys, New Haven, CT 06520 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lin, A (reprint author), Yale Univ, Dept Appl Phys, New Haven, CT 06520 USA. RI Hong, Xia/B-6710-2014; Wood, Vanessa/C-3621-2014; Specht, Eliot/A-5654-2009; OI Hong, Xia/0000-0002-7873-5774; Wood, Vanessa/0000-0001-6435-0227; Specht, Eliot/0000-0002-3191-2163; Walker, Frederick/0000-0002-8094-249X NR 20 TC 59 Z9 61 U1 0 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 2 PY 2001 VL 78 IS 14 BP 2034 EP 2036 DI 10.1063/1.1358848 PG 3 WC Physics, Applied SC Physics GA 415VT UT WOS:000167744800026 ER PT J AU Bedson, TR Palmer, RE Wilcoxon, JP AF Bedson, TR Palmer, RE Wilcoxon, JP TI Mechanism of electron-beam writing in passivated gold nanoclusters SO APPLIED PHYSICS LETTERS LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; CLUSTERS; GRAPHITE; NANOSTRUCTURES; DEPOSITION AB We have investigated the mechanism of direct electron-beam writing in thin films of passivated gold nanoclusters. The exposure of films of approximately monolayer thickness (6 nm) was investigated as a function of electron dose on various substrates. Films were obtained on various substrates: graphite, silicon, thermally grown silicon dioxide and sputtered silicon dioxide. The experimental results are compared with Monte Carlo simulations of the electron scattering. We conclude that, in the case of such monolayer films, exposure of the clusters is dominated by electrons scattered in the substrate, so that the properties of the resist depend strongly on the nanocluster/substrate combination. (C) 2001 American Institute of Physics. C1 Univ Birmingham, Sch Phys & Astron, Nanoscale Phys Res Lab, Birmingham B15 2TT, W Midlands, England. Sandia Natl Labs, Nanostruct & Adv Mat Dept, Albuquerque, NM 87185 USA. RP Bedson, TR (reprint author), Univ Birmingham, Sch Phys & Astron, Nanoscale Phys Res Lab, Birmingham B15 2TT, W Midlands, England. RI Palmer, Richard/A-5366-2008 OI Palmer, Richard/0000-0001-8728-8083 NR 17 TC 7 Z9 7 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 2 PY 2001 VL 78 IS 14 BP 2061 EP 2063 DI 10.1063/1.1357210 PG 3 WC Physics, Applied SC Physics GA 415VT UT WOS:000167744800035 ER PT J AU Cheong, HM Lee, SH Nelson, B Mascarenhas, A Deb, SK AF Cheong, HM Lee, SH Nelson, B Mascarenhas, A Deb, SK TI Evidence for light-induced long-range hydrogen motion in a-Si : H using Raman scattering of a-WO3 SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 4th International Meeting on Electrochromism (IME-4) CY AUG 21-23, 2000 CL UPPSALA, SWEDEN SP Angstrom Solar Ctr, Swedish Fdn Strateg Environm Res, Natl Swedish Energy Author DE hydrogen diffusion; hydrogenated amorphous silicon; Raman spectrum; Staebler-Wronski effect of a-WO3 ID AMORPHOUS-SILICON; METASTABILITY; DIFFUSION AB We demonstrate that one can detect minuscule amounts of hydrogen diffusion out of a-Si:H under illumination at room temperature by monitoring the changes in the Raman spectrum of a-WO3 as a function of illumination. The Staebler-Wronski effect, the light-induced creation of metastable defects in hydrogenated amorphous silicon (a-Si:H), has been one of the major problems that has limited the performance of solar cells based on this material. The recently suggested 'hydrogen collision model' can explain many aspects of the Staebler-Wronski effect, but assumes that the photogenerated mobile hydrogen atoms can move a long distance at room temperature. However, light-induced hydrogen motion in a-Si:H has not been experimentally observed at room temperature. We utilized the high sensitivity of the Raman spectrum of electrochromic a-WO3 to hydrogen insertion to probe the long-range motion of hydrogen at room temperature. We deposited a thin (200 nm) layer of a-WO3 on top of a-Si:H, and under illumination a change in the Raman spectrum was detected. By comparing the Raman signal changes with those for control experiments where hydrogen is electrochemically inserted into a-WO3, we can estimate semi-quantitatively the amount of hydrogen that diffuses out of the a-Si:H layer. Published by Elsevier Science Ltd. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Sogang Univ, Dept Phys, Seoul 121742, South Korea. RP Deb, SK (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd Golden, Golden, CO 80401 USA. RI Lee, Sehee/A-5989-2011; Cheong, Hyeonsik/D-7424-2012 OI Cheong, Hyeonsik/0000-0002-2347-4044 NR 9 TC 1 Z9 1 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD APR 2 PY 2001 VL 46 IS 13-14 BP 1963 EP 1966 DI 10.1016/S0013-4686(01)00387-5 PG 4 WC Electrochemistry SC Electrochemistry GA 422TM UT WOS:000168135400008 ER PT J AU Lee, SH Cheong, HM Liu, P Smith, D Tracy, CE Mascarenhas, A Pitts, JR Deb, SK AF Lee, SH Cheong, HM Liu, P Smith, D Tracy, CE Mascarenhas, A Pitts, JR Deb, SK TI Raman spectroscopic studies of gasochromic a-WO3 thin films SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 4th International Meeting on Electrochromism (IME-4) CY AUG 21-23, 2000 CL UPPSALA, SWEDEN SP Angstrom Solar Ctr, Swedish Fdn Strateg Environm Res, Natl Swedish Energy Author DE gasochromic; tungsten oxide; Raman; heavy oxygen ID MECHANISM AB The gasochromic mechanism in amorphous tungsten oxide films has been investigated using Raman scattering measurements and optical cycling tests. The Raman spectra of as-deposited films show two strong peaks at 770 and 950 cm(-1) due to vibrations of the O-W6+-O and W6+=O bonds, respectively. When the Pd/a-WO3 films are gasochromically colored by exposure to diluted hydrogen gas, extra Raman peaks due to O-W5+-O and W5+=O bonds appear at 330 and 450 cm(-1), respectively. Optical cycling tests confirm that the Pd/a-WO3, films can not be bleached without oxygen. The Raman spectra of a-WO3 films bleached with isotopic heavy oxygen (O-18) show that the gasochromic coloration in a-WO3 films is directly related to the double injection of hydrogen ions and electrons. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Sogang Univ, Dept Phys, Seoul 121742, South Korea. DCH Technol Inc, Valencia 91355, Spain. RP Lee, SH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Lee, Sehee/A-5989-2011; Cheong, Hyeonsik/D-7424-2012; Liu, Ping/I-5615-2012 OI Cheong, Hyeonsik/0000-0002-2347-4044; NR 12 TC 67 Z9 74 U1 2 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD APR 2 PY 2001 VL 46 IS 13-14 BP 1995 EP 1999 DI 10.1016/S0013-4686(01)00379-6 PG 5 WC Electrochemistry SC Electrochemistry GA 422TM UT WOS:000168135400014 ER PT J AU Richardson, TJ Rubin, MD AF Richardson, TJ Rubin, MD TI Liquid phase deposition of electrochromic thin films SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 4th International Meeting on Electrochromism (IME-4) CY AUG 21-23, 2000 CL UPPSALA, SWEDEN SP Angstrom Solar Ctr, Swedish Fdn Strateg Environm Res, Natl Swedish Energy Author DE liquid phase deposition; electrochromic films; thin film electrodes ID AQUEOUS-SOLUTION; OXIDE AB Thin films of titanium, zirconium and nickel oxides were deposited on conductive SnO2:F glass substrates by immersion in aqueous solutions. The films are transparent, conformal, of uniform thickness and appearance, and adhere strongly to the substrates. On electrochemical cycling, TiO2, mixed TiO2-ZrO2, and NiOx films exhibited stable electrochromism with high coloration efficiencies. These nickel oxide films were particularly stable compared with films prepared by other non-vacuum techniques. The method is simple, inexpensive, energy efficient, and readily scalable to larger substrates. Published by Elsevier Science Ltd. C1 Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Richardson, TJ (reprint author), Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 18 TC 30 Z9 32 U1 1 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD APR 2 PY 2001 VL 46 IS 13-14 BP 2119 EP 2123 DI 10.1016/S0013-4686(01)00389-9 PG 5 WC Electrochemistry SC Electrochemistry GA 422TM UT WOS:000168135400033 ER PT J AU Deb, SK Lee, SH Tracy, CE Pitts, JR Gregg, BA Branz, HM AF Deb, SK Lee, SH Tracy, CE Pitts, JR Gregg, BA Branz, HM TI Stand-alone photovoltaic-powered electrochromic smart window SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 4th International Meeting on Electrochromism (IME-4) CY AUG 21-23, 2000 CL UPPSALA, SWEDEN SP Angstrom Solar Ctr, Swedish Fdn Strateg Environm Res, Natl Swedish Energy Author DE smart windows; photovoltaics; electrochromics; silicon-carbon alloys; dye-sensitized TiO2 AB Three different, innovative approaches have been taken to develop photovoltaic (PV) integrated electrochromic (EC) devices for smart-window applications. These are: (i) a stand-alone, side-by-side PV-powered EC window; (ii) a monolithically integrated PV-EC device; and (iii) a never photoelectrochromic device based on a dye-sensitized TiO2 solar cell. The compatibility of PV-EC devices has been analyzed: and the potential for large energy savings for building applications has been suggested. The first monolithic, amorphous-silicon based, PV-powered electrochromic window is described in detail. The device employs a wide bandgap a-Si1-xCx/H n-i-p PV cell as a semitransparent power source, and a LiyWO3/LiAlF4/V2O5 EC device as an optical-transmittance modulator. The EC device is deposited directly on top of a PV cell that coats a glass substrate. The a-Si1-xCx/H PV cell has a gap of 2.5 eV and a transmittance of 60-80% over a large portion of the visible light spectrum. Our prototype 16-cm(2) PV-EC device modulates the transmittance by more than 60% over a large portion of the Visible spectrum. The coloring and bleaching times of the EC device are approximately 1 min under normal operating conditions (+/- 1 V). A brief description of photoelectrochromic windows based on a combination of dye-sensitized TiO2 and WO3 EC-layer is also given. Published by Elsevier Science Ltd. C1 Natl Renewable Energy Lab, Ctr Basic Sci 5900, Golden, CO 80401 USA. RP Deb, SK (reprint author), Natl Renewable Energy Lab, Ctr Basic Sci 5900, 1617 Cole Blvd, Golden, CO 80401 USA. RI Lee, Sehee/A-5989-2011 NR 14 TC 56 Z9 59 U1 4 U2 42 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD APR 2 PY 2001 VL 46 IS 13-14 BP 2125 EP 2130 DI 10.1016/S0013-4686(01)00390-5 PG 6 WC Electrochemistry SC Electrochemistry GA 422TM UT WOS:000168135400034 ER PT J AU Lee, SH Tracy, CE Jorgensen, G Pitts, JR Deb, SK AF Lee, SH Tracy, CE Jorgensen, G Pitts, JR Deb, SK TI Cyclic environmental testing of electrochromic window devices SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 4th International Meeting on Electrochromism (IME-4) CY AUG 21-23, 2000 CL UPPSALA, SWEDEN SP Angstrom Solar Ctr, Swedish Fdn Strateg Environm Res, Natl Swedish Energy Author DE electrochromic windows; accelerated environmental testing; activation analysis studies; interfacial analysis studies ID THIN-FILMS; DIFFUSION AB We report on a systematic study of the factors affecting the degradation of prototype electrochromic (EC) windows. Our research activities include accelerated lifetime testing, activation analysis studies (AAS), and interfacial analysis studies. EC windows made by several different US companies were subjected to alternate coloring and bleaching voltage cycles while exposed to simulated 1.2-sun UV irradiance in a temperature-controlled environmental chamber. The samples inside the chamber were tested under a matrix of four different environmental test conditions at nominal sample temperatures of 85 degreesC: cycling under irradiance, cycling with no irradiance, irradiance with no cycling, and simple thermal exposure with no cycling. In another accelerated environmental test, we evaluated device performance as a function of activation spectra. We used a series of cut-on filters for performing AAS of photolytically induced degradation of EC window devices. Finally, to identify the interface at which degradation occurs during cycling, we employed electrochemical impedance spectroscopy (ECIS). The ECIS and electro-optical measurements were systematically and periodically repeated to discover any changes in electrochemical behavior as a function of cycling. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Natl Renewable Energy Lab, Ctr Basic Sci, Golden, CO 80401 USA. RP Lee, SH (reprint author), Natl Renewable Energy Lab, Ctr Basic Sci, 1617 Cole Blvd, Golden, CO 80401 USA. RI Lee, Sehee/A-5989-2011 NR 17 TC 6 Z9 7 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD APR 2 PY 2001 VL 46 IS 13-14 BP 2237 EP 2242 DI 10.1016/S0013-4686(01)00366-8 PG 6 WC Electrochemistry SC Electrochemistry GA 422TM UT WOS:000168135400051 ER PT J AU Richardson, TJ Slack, JL Rubin, MD AF Richardson, TJ Slack, JL Rubin, MD TI Electrochromism is copper oxide thin films SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 4th International Meeting on Electrochromism (IME-4) CY AUG 21-23, 2000 CL UPPSALA, SWEDEN SP Angstrom Solar Ctr, Swedish Fdn Strateg Environm Res, Natl Swedish Energy Author DE electrochromism; copper; copper oxide; thin films; electrochemical switching ID INSITU RAMAN-SPECTROSCOPY; ANODIC-OXIDATION; DEPOSITION; ELECTRODES; MEDIA AB Transparent thin films of copper(I) oxide prepared on conductive SnO2/F glass substrates by anodic oxidation of sputtered copper films or by direct electrodeposition of Cu2O transformed reversibly to opaque metallic copper films when reduced in alkaline electrolyte. In addition, the same Cu2O films transform reversibly to black copper(II) oxide when cycled at more anodic potentials. Copper oxide-to-copper switching covered a large dynamic range, from 85 to 10% photopic transmittance, with a coloration efficiency of about 32 cm(2)/C. Gradual deterioration of the switching range occurred over 20-100 cycles. This is tentatively ascribed to coarsening of the film and contact degradation caused by the 65% volume change on conversion of Cu to Cu2O. Switching between the two copper oxides (which have similar volumes) was more stable and more efficient (CE = 60 cm(2)/C), but covered a smaller transmittance range (60-44% T). Due to their large electrochemical storage capacity and tolerance for alkaline electrolytes, these cathodically coloring films may be useful as counter electrodes for anodically coloring electrode films such as nickel oxide or metal hydrides. Published by Elsevier Science Ltd. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Richardson, TJ (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 19 TC 66 Z9 67 U1 1 U2 21 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD APR 2 PY 2001 VL 46 IS 13-14 BP 2281 EP 2284 DI 10.1016/S0013-4686(01)00397-8 PG 4 WC Electrochemistry SC Electrochemistry GA 422TM UT WOS:000168135400058 ER PT J AU Whalley, SA Murray, JM Brown, D Webster, GJM Emery, VC Dusheiko, GM Perelson, AS AF Whalley, SA Murray, JM Brown, D Webster, GJM Emery, VC Dusheiko, GM Perelson, AS TI Kinetics of acute hepatitis B virus infection in humans SO JOURNAL OF EXPERIMENTAL MEDICINE LA English DT Article DE acute hepatitis B; kinetics; cytotoxic T lymphocytes; mutation; hepatocyte ID ACUTE VIRAL-HEPATITIS; SURFACE-PROTEINS; IN-VIVO; DNA; HEPATOCYTES; REPLICATION; DYNAMICS; GENOME; CELLS; CLEARANCE AB Using patient data from a unique single source outbreak of hepatitis B virus (HBV) infection, we have characterized the kinetics of acute HBV infection by monitoring viral turnover in the serum during the late incubation and clinical phases of the disease in humans. HBV replicates rapidly with minimally estimated doubling times ranging between 2.2 and 5.8 d (mean 3.7 +/- 1.5 d), After a peak viral load in serum of nearly 10(10) HBV DNA copies/ml is attained, clearance of HBV DNA follows a two or three phase decay pattern with an initial rapid decline characterized by mean half-life (t(1/2)) of 3.7 +/- 1.2 d, similar to the t(1/2) observed in the noncytolytic clearance of covalently closed circular DNA for other hepadnaviruses. The final phase of virion clearance occurs at a variable rate (t(1/2) of 4.8 to 284 d) and may relate to the rate of loss of infected hepatocytes. Free virus has a mean t(1/2) of at most 1.2 +/- 0.6 d. We estimate a peak HBV production rate of at least 10(13) virions/day and a maximum production rate of an infected hepatocyte of 200-1,000 virions/day, on average. At this peak rate of virion production we estimate that every possible single and most double mutations would be created each day. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. UCL Royal Free & Univ Coll Med Sch, Dept Virol, London NW3 2QG, England. UCL Royal Free & Univ Coll Med Sch, Dept Med, Ctr Hepatol, London NW3 2QG, England. Univ New S Wales, Sch Math, Sydney, NSW 2052, Australia. RP Perelson, AS (reprint author), Los Alamos Natl Lab, Div Theoret, MS-K710, Los Alamos, NM 87545 USA. EM asp@lanl.gov RI Murray, John/B-5481-2009 OI Murray, John/0000-0001-9314-2283 FU NCRR NIH HHS [R01 RR006555, RR06555] NR 32 TC 95 Z9 99 U1 0 U2 2 PU ROCKEFELLER UNIV PRESS PI NEW YORK PA 1114 FIRST AVE, 4TH FL, NEW YORK, NY 10021 USA SN 0022-1007 J9 J EXP MED JI J. Exp. Med. PD APR 2 PY 2001 VL 193 IS 7 BP 847 EP 853 DI 10.1084/jem.193.7.847 PG 7 WC Immunology; Medicine, Research & Experimental SC Immunology; Research & Experimental Medicine GA 420WN UT WOS:000168028400008 PM 11283157 ER PT J AU Moghadam, NY Stocks, GM Zhang, XG Nicholson, DMC Shelton, WA Wang, Y Faulkner, JS AF Moghadam, NY Stocks, GM Zhang, XG Nicholson, DMC Shelton, WA Wang, Y Faulkner, JS TI Angular momentum convergence of Korringa-Kohn-Rostoker Green's function methods SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID APPROXIMATION; ENERGY AB The convergence of multiple-scattering-theory-based electronic structure methods (e.g. the Korringa-Kohn-Rostoker (KKR) band theory method), is determined by l(max), the maximum value of the angular momentum quantum number l. It has been generally assumed that l(max) = 3 or 4 is sufficient to ensure a converged ground state and other properties. Using the locally self-consistent multiple-scattering method, which facilitates the use of very high values of l(max), it is shown that the convergence of KKR Green's function methods is much slower than previously supposed, even when spherical approximations to the crystal potential are used. Calculations for Cu using 3 less than or equal to l(max) less than or equal to 16 indicate that the total energy is converged to within similar to0.04 mRyd l(max) = 12. For both face-centred cubic and body-centred cubic structures, the largest error in the total energy occurs at l(max) = 4; l(max) = 8 gives total energies, bulk moduli, and lattice constants that are converged to accuracies of 0.1 mRyd, 0.1 Mbar, and 0.002 Bohr respectively. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Pittsburgh Supercomp Ctr, Pittsburgh, PA 15213 USA. Florida Atlantic Univ, Boca Raton, FL 33431 USA. RP Moghadam, NY (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Stocks, George Malcollm/Q-1251-2016 OI Stocks, George Malcollm/0000-0002-9013-260X NR 17 TC 8 Z9 8 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 APR 2 PY 2001 VL 13 IS 13 BP 3073 EP 3081 DI 10.1088/0953-8984/13/13/318 PG 9 WC Physics, Condensed Matter SC Physics GA 461RB UT WOS:000170376300021 ER PT J AU Fishman, RS AF Fishman, RS TI Spin-density waves in Fe/Cr trilayers and multilayers SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Review ID LAYERED MAGNETIC-STRUCTURES; BRILLOUIN LIGHT-SCATTERING; QUANTUM-WELL STATES; CALCULATED OSCILLATION PERIODS; ULTRATHIN CR FILMS; INTERLAYER EXCHANGE; TEMPERATURE-DEPENDENCE; ELECTRONIC-STRUCTURE; CHROMIUM-ALLOYS; PHASE-DIAGRAM AB This paper reviews the behaviour of spin-density waves (SDWs) in Fe/Cr trilayers and multilayers. After providing an overview of SDWs in bulk Cr, we discuss the predicted effects of SDWs on the exchange coupling of an Fe/Cr trilayer with perfect interfaces, which is nearly realized experimentally by a Cr wedge grown atop an Fe whisker and covered with a thin Fe film. While the observed phase slips in the exchange coupling are produced by transitions between collinear SDW phases with different numbers of nodes, the growth in the distance between phase slips with increasing temperature is attributed to a transition between incommensurate and commensurate SDWs. The theoretical consequences of Fe-Cr interdiffusion and interfacial steps at imperfect interfaces are then described. Whereas Fe-Cr interdiffusion causes the observed sign change in the exchange coupling, the effects of interfacial steps depend on which of the interfacial, magnetostatic, or bulk energies are dominant. For rough interfaces, the non-collinear coupling between the Fe moments can be explained by two competing models, one of which requires the formation of a non-collinear, helical SDW that is unstable in bulk Cr. Although both collinear and non-collinear SDWs have been directly observed in Fe/Cr multilayers with neutron scattering, the role of SDWs in the exchange coupling remains uncertain. This review focuses on the following open questions. Can a SDW be detected from the exchange coupling alone? What are the requirements for a non-collinear SDW in an Fe/Cr trilayer or multilayer? Can the proximity to a SDW instability be observed? Finally, what is the origin of the discrepancy between the observed exchange coupling and the much larger coupling predicted by phenomenological, tight-binding, and first-principles calculations?. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Fishman, Randy/C-8639-2013 NR 158 TC 67 Z9 67 U1 0 U2 10 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 EI 1361-648X J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD APR 2 PY 2001 VL 13 IS 13 BP R235 EP R269 DI 10.1088/0953-8984/13/13/201 PG 35 WC Physics, Condensed Matter SC Physics GA 461RB UT WOS:000170376300003 ER PT J AU Schlesinger, TE Toney, JE Yoon, H Lee, EY Brunett, BA Franks, L James, RB AF Schlesinger, TE Toney, JE Yoon, H Lee, EY Brunett, BA Franks, L James, RB TI Cadmium zinc telluride and its use as a nuclear radiation detector material SO MATERIALS SCIENCE & ENGINEERING R-REPORTS LA English DT Review DE cadmium zinc telluride; nuclear detector; spectroscopy ID PHYSICAL VAPOR TRANSPORT; HIGH-PRESSURE BRIDGMAN; ELECTRON-PARAMAGNETIC-RESONANCE; LEVEL TRANSIENT SPECTROSCOPY; GAMMA-RAY SPECTROMETERS; TRAVELING HEATER METHOD; MOLECULAR-BEAM EPITAXY; II-VI SEMICONDUCTORS; HIGH-RESOLUTION CDTE; INDIUM-DOPED CDTE AB We present a comprehensive review of the material properties of cadmium zinc telluride (CZT, Cd1-xZnxTe) with zinc content x = 0.1-0.2. Particular emphasis is placed on those aspects of this material related to room temperature nuclear detectors. A review of the structural properties, charge transport, and contacting issues and how these are related to detector and spectrometer performance is presented. A comprehensive literature survey and bibliography are also included. (C) 2001 Elsevier Science B.V, AII rights reserved. C1 Carnegie Mellon Univ, Dept Elect & Comp Engn, Pittsburgh, PA 15213 USA. Spire Corp, Bedford, MA 01730 USA. Spectrolab Inc, Sylmar, CA USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Schlesinger, TE (reprint author), Carnegie Mellon Univ, Dept Elect & Comp Engn, Pittsburgh, PA 15213 USA. NR 261 TC 523 Z9 557 U1 8 U2 99 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0927-796X J9 MAT SCI ENG R JI Mater. Sci. Eng. R-Rep. PD APR 2 PY 2001 VL 32 IS 4-5 BP 103 EP 189 DI 10.1016/S0927-796X(01)00027-4 PG 87 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 422BL UT WOS:000168098000001 ER PT J AU Carena, M Moreno, JM Quiros, M Seco, M Wagner, CEM AF Carena, M Moreno, JM Quiros, M Seco, M Wagner, CEM TI Supersymmetric CP-violating currents and electroweak baryogenesis SO NUCLEAR PHYSICS B LA English DT Review ID ELECTRIC-DIPOLE MOMENTS; LARGE-TAN-BETA; WEINBERG-SALAM THEORY; BUBBLE WALL PROFILES; MSSM HIGGS-BOSON; STANDARD MODEL; PHASE-TRANSITION; FINITE-TEMPERATURE; BARYON ASYMMETRY; DIMENSIONAL REDUCTION AB In this work we compute the CP-violating currents of the right-handed stops and higgsinos, induced by the presence of non-trivial vacuum expectation values of the Higgs fields within the context of the minimal supersymmetric extension of the Standard Model (MSSM) with explicit CP-violating phases. Using the Keldysh formalism, we perform the computation of the currents at finite temperature, in an expansion of derivatives of the Higgs fields, Contrary to previous works, we implement a resummation of the Higgs mass insertion effects to all orders in perturbation theory. White the components of the right-handed stop current j((t) over tildeR)(mu) become proportional to the difference H-2 a(mu) H-1 - H-1 a(mu) H-2 (suppressed by Delta beta), the higgsino currents, j((H) over tildel)(mu), proportional to both H(2)a(mu)H(1) +/- H-1 a(mu)H(2). For large values of the charged Higgs mass and moderate values of tan B the contribution to the source proportional to H(2)a(mu)H(1) + H(1)a(mu)H(2) in the diffusion equations become sizeable, although it is suppressed by the higgsino number violating interaction rate Gamma (-1/2)(mu). For small values of the wall velocity, 0.04 less than or equal to v(omega) less than or equal to 0.1, the total contribution leads to acceptable values of the baryon asymmetry for values of the CP-violating phases phi (CP) in the range 0.04 less than or equal to | sin phi (CP)| less than or equal to 1. Finally, we comment on the relevance of the latest results of Higgs searches at LEP2 for the mechanism of electroweak baryogenesis within the MSSM, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. CSIC, Inst Estructura Mat, E-28006 Madrid, Spain. Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM mariano@makoki.iem.csic.es RI Seco, Marcos/A-3886-2015 OI Seco, Marcos/0000-0003-0354-8699 NR 107 TC 132 Z9 132 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD APR 2 PY 2001 VL 599 IS 1-2 BP 158 EP 184 DI 10.1016/S0550-3213(01)00032-3 PG 27 WC Physics, Particles & Fields SC Physics GA 420CY UT WOS:000167987400007 ER EF